CN1695224A - Fluorescent lamp and its manufacturing method, and illuminating apparatus - Google Patents

Abstract

A fluorescent lamp (1) comprises a bulb (2) and bases (6). The bulb (2) is composed of bent portions (2c) and straight portions (2b) adjoining the bent portions (2c). The portions (2c, 2b) are formed by heating and bending bent-portion-forming portions of a straight bulb (2a) having a bulb outside diameter of 12 to 20 mm and a bulb length of 800 to 2500 mm. The straight portions (2b) lie in the same plane, with the bent portions (2c) interposed between the straight portions (2d). The bulb (2) has a pair of ends (2d) near each other where electrodes (5, 5) are so sealingly provided that a discharge path is formed from the straight and bent portions (2b, 2c). A phosphor layer (4) is formed on the inner surface of the bulb (2), and a discharge medium containing mercury is sealed in the bulb (2). The bases (6) are provided at both ends (2d, 2d) of the bulb (2). The thermal degradation of the fluorescent layer (4) formed in the straight portions (2b) is reduced, and the initial luminous flux deterioration is reduced, enabling operation of the florescent lamp with high efficiency. With such a constitution, a small fluorescent lamp that can be operated with high efficiency and has an improved light output characteristics and an illuminating apparatus using such a fluorescent lamp can be provided.

Description

Fluorescent lamp, its manufacturing method and lighting equipment

technical field

The present invention relates to a fluorescent lamp, its manufacturing method and lighting equipment using the fluorescent lamp.

Background technique

Fluorescent lamps of straight tube shape, ring shape, and single-ended shape are known as general fluorescent lamps, and in particular, small-diameter ring fluorescent lamps for high-frequency lighting equipment have been developed and manufactured as products in view of demands for energy conservation and resource conservation in recent years . Such a small-diameter annular fluorescent lamp is represented by the product name "FHC" (see Patent Document 1). This small-diameter annular fluorescent lamp has an outer diameter of approximately the same annular size as a conventional annular fluorescent lamp, but the outer diameter of the tube can be made smaller while ensuring brightness equal to or greater than that of a conventional annular fluorescent lamp, thereby satisfying energy conservation and resources The need for preservation, in particular, allows the realization of a comfortable visual environment in domestic spaces.

On the other hand, square fluorescent lamps are conventionally known (see Patent Documents 2 and 3). The fluorescent lamp described in Patent Document 2 is a 30W type square fluorescent lamp, which uses a square bulb with a tube outer diameter of 25-32 mm, and the inner side of the curved part has a curvature radius of 20-40 mm, and the outer part between the opposite straight parts The diameter is 190-220mm. The fluorescent lamp described in Patent Document 3 is a square fluorescent lamp using a square bulb having an outer diameter of a tube of 12.75 to 13.25 mm, and the outer diameter between relatively straight parts is 135 mm, and the discharge path length is 450 mm to 470 mm (tube length is 500 to 520mm).

[Patent Document 1] Japanese Patent No. 3055769

[Patent Document 2] Japanese Patent Laid-Open Publication No. SHO58-152365

[Patent Document 3] Japanese Patent Laid-Open Publication No. HEI3-59548

By forming a protective layer and a fluorescent layer in a straight bulb, sealing the electrodes to both ends, heating to soften the entire straight bulb, and bending the straight bulb into a ring shape, the initial luminous flux tends to be lowered, thereby forming the small-diameter annular fluorescent lamp according to Patent Document 1. In addition, the alkali component in the bulb is precipitated due to heat treatment and reacts with the fluorescent layer, thereby causing problems of easy degradation and low lumen maintenance factor with the lapse of time.

Also, the small-diameter annular fluorescent lamp is formed into a ring shape by a straight tube bulb while being stretched in the longitudinal direction, which easily causes the protective layer and fluorescent layer formed in the straight tube to be broken when forming, thereby resulting in that the protective layer and fluorescent layer cannot be formed thickly. The problem. In general, the thicker the fluorescent layer is formed, the higher the initial luminous flux, and the thicker the protective layer allows the luminous flux maintenance factor to be increased. However, with the small-diameter annular fluorescent lamp, the protective layer and the phosphor layer cannot be formed thickly for the above reasons, and thus there is a limit to the degree of improvement of the initial luminous flux and the degree of improvement of the luminous flux maintenance factor.

The square fluorescent lamp according to Patent Document 2 simply shapes a commonly used large-diameter 30W fluorescent lamp into a square shape, and does not take bulb forming process or improvement of lamp performance into consideration.

Since the square fluorescent lamp according to Patent Document 3 has a short tube length of 500-520 mm, light output is low, and high output lighting as in conventional small ring fluorescent lamps cannot be expected. In particular, the outer diameter between the relatively straight parts of 135mm is very short, so that a pair of electrodes must be arranged to bend toward the inside of the bulb, causing inconvenience, thereby making the manufacture complicated, and it is impossible to use the same type of bulb with the same Bulbs of different shapes but different sizes combined in the setup.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fluorescent lamp which is small in size, highly efficient and has improved light output performance, and a lighting device using the fluorescent lamp.

Contents of the invention

Fluorescent lamps of the present invention include:

Bulb formed by heating a bent portion of a straight tube-shaped bulb member with an outer tube diameter of 12-20mm and a tube length of 800-2500mm-forming a predetermined portion so as to provide a plurality of bent portions and the same with the bent portion by bending processing Adjacent straight pipe portions such that the straight pipe portions are generally arranged in the same plane through the curved portion; electrodes sealed therein are formed adjacent to a pair of end portions so as to form a discharge path through the straight pipe portion and the curved portion ; forming a phosphor layer on the inner surface of the bulb; and sealing the discharge medium including mercury; and

A lamp cap provided at the end of the bulb.

The bulb is formed of a plurality of straight pipe parts and bent parts connecting the straight pipe parts so that the parts communicate with each other. The curved portion is formed by heating the curved portion-forming predetermined portions and bending these portions on a single straight tube-shaped bulb. This can be formed by bending several straight bulbs and connecting the ends to each other.

The curved portion may be a simple curved straight tube shaped bulb, or may be shaped by winding in a drum or by molding so that the cross section of the curved portion is approximately the same shape as that of the straight tube portion.

The tube length of a straight bulb is about the same as the discharge path length, and accordingly, considering producing a light output equal to that of a conventional small-diameter circular fluorescent lamp, the tube length must be in the range of 800-3000 mm, preferably in the range of 800-2500 mm.

The inner diameter of the straight tube portion is in the range of 12-20 mm, and the preferred range of the inner diameter of the straight tube portion is 14-18 mm in consideration of lamp performance such as lamp efficiency and manufacturing conditions. It should also be noted that, for the purposes of the present invention, the greater portion of the straight pipe portion is within the above range, although the straight pipe portion near the bend may have an outer diameter that has changed due to the shaping of the bend and is not within the above range Inside is enough.

It is known that generally, the smaller the tube diameter of the fluorescent lamp, the more the lamp efficiency is improved, and in the present invention, the outer tube diameter of the straight tube part is 20 mm or less. A light efficiency equal to that of a conventional small-diameter annular fluorescent lamp can be realized for an outer pipe diameter of 20 mm or less for the straight pipe portion. On the other hand, it is unacceptable that the outer tube diameter of the straight tube part is less than 12mm, because it is difficult to ensure the mechanical strength of the glass bulb with the curved part, and this setting is not feasible, because the conventional tube equal to the same size cannot be obtained. Lamp efficiency of ring fluorescent lamps.

In order to increase the lamp efficiency of a conventional circular fluorescent lamp having an outer tube diameter of 29mm (type designation "FCL") by 10% or more, the outer tube diameter must be reduced to 65% or less. That is, for straight pipe sections it will be necessary to provide an outer pipe diameter of 18 mm or less. Also, for the outer tube diameter, it is sufficient to reduce the thickness of the fluorescent lamp. In consideration of properties such as light output and lamp efficiency, it is preferable that the outer tube diameter at the straight tube portion is 14 mm or more.

The bulb has three or more straight pipe parts, and the number of bent parts for connecting the straight pipe parts is formed one less than the number of straight pipe parts. The bent portion is formed such that the straight pipe portion lies substantially in the same plane. Electrodes are sealed in ends of straight pipe portions at both ends on which no bent portions are provided so that both ends of the electrodes are closely disposed.

The bulb forms a single discharge path surrounding the center in positional relationship of substantially a plurality of straight pipe sections. That is, in the bulb, the insides of the straight tube parts are connected by the bent part, and a single discharge path is formed by a pair of electrodes sealed at both end parts. Furthermore, the straight pipe portions do not have to have the same length, and only one straight pipe portion having different lengths may be provided. Where four straight tube sections having the same tube length are joined by three curved sections, the bulb will provide a generally square shape due to the straight tube sections.

It is sufficient that the shape of the bulb has a polygon, but not limited thereto, the bulb may have a pentagon or a hexagon. In addition, an arrangement in which two bulbs with different lengths on each side are concentrically arranged on the same plane can be further provided, with one bulb on the inside and the other bulb on the outside, and the ends of the bulbs can be connected in an airtight manner, thereby forming Double tube.

A phosphor layer will be coated and formed on the inner surface of the straight tube-shaped bulb before forming the bent portion.

The lamp base has an electrical connection to a power supply component such as a socket. This connecting portion may be provided at a position spaced from both ends of the bulb. In addition, the base may have a structure serving as a fixing portion by being mechanically connected to the power supply part.

According to the present invention, only the curved portion-forming predetermined portion of the straight tube-shaped bulb having an outer tube diameter of 12-20mm is heated to be softened, and the curved portion is formed so as to alleviate thermal degradation of the fluorescent layer formed on the straight tube portion , and suppress the reduction of the initial luminous flux, thereby lighting the lamp with higher efficiency.

In addition, the straight tube portion of the bulb does not bend under heat softening, so that cracking or peeling of the fluorescent layer and the protective layer does not easily occur even when the fluorescent layer and the protective layer are formed thickly, and the damage due to such cracking or peeling can be improved. The resulting poor appearance and lumen maintenance factor drop.

According to the fluorescent lamp of the above structure and performance, the curved portion-forming predetermined portion is preferably curved so that the radius of curvature on the inner side surface of the curved portion is 1-3 times the outer diameter of the tube, and the amount of the fluorescent layer bonded to the curved portion (mg/cm ² ) is 1/2 or more of the straight pipe part.

According to the setting that the radius of curvature on the inner side surface of the bent portion is small, the glass stretches greatly on the outer side of the bent portion, and the fluorescent layer is easily peeled off. However, with the arrangement of the invention, a straight bulb having an outer diameter of 12-20 mm is bent so that the glass stretch on the outside can be made smaller than that of a conventional straight bulb having an outer diameter of 25 mm or more. However, in the case where the radius of curvature on the inside surface is smaller than the diameter of the outer tube, since peeling of the phosphor layer remarkably occurs, the radius of curvature must be equal to or larger than the diameter of the outer tube. In addition, the percentage of the curved portion in the bulb obtained by bending a straight bulb having a tube length of 800-2500 mm becomes large by using a curved portion having a radius of curvature on the inside surface greater than three times the outer tube diameter of the straight tube portion, by This does not lead to an increase in lamp efficiency as expected. In addition, the shape of the bulb has a gradually curved curved portion, so that the length of the discharge path becomes smaller, and the apparent size of the polygonal bulb is reduced. Thus, the radius of curvature must be three times or less the outer diameter of the straight pipe portion.

In addition, the amount of the phosphor layer bonded to the bent portion becomes smaller per area increment (mg/cm ² ) because the outer glass portion is stretched, but when the bent portion is bent—forming a predetermined portion, by adjusting the The stretching of the glass portion can make the peeling of the phosphor layer less noticeable, so that the amount of bonding becomes 1/2 or more of that on the straight tube portion, and the desired light output can also be obtained from the curved portion.

The curved portion is defined herein as the area between the points where the curved inner and outer surfaces meet the outer peripheral surface of the adjacent straight pipe portion. Accordingly, it is not necessary to form a predetermined portion according to the bent portion of the straight tube-shaped bulb, and it is of course desirable to perform the bending process with a small difference therebetween.

According to the above-mentioned fluorescent lamp, the application amount of the phosphor particles on the straight tube portion is preferably 4.0-7.5 mg/cm ² . At application levels less than 4.0 mg, the benefit of improved light output relative to conventional small diameter circular fluorescent lamps diminishes. On the other hand, in the case where the applied amount of phosphor particles on the straight tube portion exceeds 6.0 mg/cm ² , the phosphor layer may start to peel off at the curved portion, and when it exceeds 7.5 mg/cm ² , due to the increased The advantage of increasing the light output due to thickness is not significant.

Correspondingly, by applying 4.0-7.5 mg/cm ² of phosphor particles constituting the fluorescent layer in the straight pipe portion, the light output can be increased, and by setting this range to 4.0-6.0 mg/cm ² , the light output in the straight pipe portion can be suppressed. The cracking and peeling of the fluorescent layer.

Furthermore, according to the above fluorescent lamp, the bent portion-forming predetermined portion has a range of 5-50%, preferably 15-50%, of the total length of the straight tube-shaped bulb.

The greater the percentage of the straight tube, which has little thermal degradation of the phosphor layer, the less degradation in initial luminous flux and the more the light output is improved for the entire bulb. Thus, the length of the bent portion-forming predetermined portion is 50% or less of the total length of the straight tube-shaped bulb. In the case where the length of the bent portion-formation predetermined portion exceeds 50%, the amount of the phosphor layer degraded due to heat generation at the time of bending increases, and improvement in light output becomes poor. On the other hand, in the case where the length of the bent portion-forming predetermined portion is less than 5%, it is difficult to bend the portion to be bent, and it is also difficult to obtain the desired mechanical strength of the bent portion.

With the above arrangement, since the length of the bent portion-formation predetermined portion is in the range of 5-50% of the total length of the straight tube type bulb, the length of the straight tube portion having little degradation of the fluorescent layer becomes appropriately large. Thus, a fluorescent lamp that is easy to manufacture, can secure mechanical strength, and can realize light output with high improvement.

According to the fluorescent lamp of the above features, the protective layer can be formed on the inner surface of the bulb with a thickness of 0.5 [mu]m or more.

In the case where the protective layer has a thickness of 0.5 μm or more, cracking of the fluorescent layer or the protective layer on the bent portion can be suppressed, and also the reaction between the alkali component in the bulb and mercury and the injection of mercury into the bulb can be suppressed. phenomenon, thereby reducing mercury consumption during lamp ignition. Moreover, since the straight tube portion does not stretch substantially, there is no need to worry about the occurrence of protection on the straight tube portion during the bending process even when the thickness of the protective layer formed in the straight tube type bulb is increased to 0.5 μm or thicker. Layer cracking, etc., so that the function of the protective layer can be fully displayed.

Furthermore, according to the present invention, in the case where the protective layer of a fluorescent lamp has a thickness of 0.5 μm or more, in addition to the function of the protective layer, mercury consumption is greatly reduced along with the fact that the straight pipe portion is not directly heated to the softening point. Thus, even if 0.15mg/W or less of mercury is sealed in each lamp watt, it is assured that the mercury will not be depleted during the rated life expectancy of the lamp and that the lamp can maintain light output.

In the above fluorescent lamp, the bulb is formed into a substantially rectangular shape with five straight tube portions, and bent portions are formed at each diagonal position of the rectangle, and caps are provided on both end portions of the bulb at the center of one side of the substantially rectangular shape.

According to this structure, it is possible to provide a light source in which the light emitting portion forms a side of a rectangle, and the base is arranged substantially at the center of one side of the rectangle so that both ends of the bulb are arranged on substantially the same straight line, thereby simplifying the The structure used to fix the lamp head.

Preferably, the fluorescent lamp with the above structure further includes a rotation limiting member for limiting the rotation angle of the lamp base relative to both ends of the bulb within a predetermined angle range.

According to this structure, the rotation of the lamp cap at a predetermined angle can be restricted by the rotation restricting member, so as to prevent the external lead wire from being pulled out and broken, or to prevent the end of the bulb from breaking, or to prevent the ignition circuit from being caused by a pair of external lead wires being short-circuited to each other. Damage, or protruding of a portion fused to a cap pin, etc., in which the external lead is connected to a pair of electrodes, and then extends through both ends of the bulb in an airtight manner with the outside and is connected to a terminal such as a pin of the cap.

The rotation limiting angle is preferably within 45 degrees for the forward and reverse rotation directions. This is based on the following reasons: By properly adjusting the position of the lamp head pins while rotating the lamp head in the forward and reverse directions within 45 degrees, the range that can be connected to the power socket on the lighting device can be expanded, and at the same time, it is possible to prevent the external lead from being broken and damaged. Cracking of the ends of the glass bulb and damage to the ignition circuit caused by a pair of external lead wires shorting to each other.

Furthermore, according to the above-mentioned fluorescent lamp, the rotation restricting member may be constituted by the cap and both end portions of the bulb fitted with the cap so as to provide its axial cross-sectional shape as an elliptical shape.

According to this structure, the cap and the end portion of the bulb to which the cap is fitted have an elliptical axial cross-sectional shape, thereby preventing the cap from rotating. Thus, cracking or loosening of the external lead wires, damage to the ignition circuit and cracking of the bulb end due to the short circuit of the pair of the external lead wires, and cracking of the bulb end can be prevented.

In the above-mentioned fluorescent lamp, the rotation restricting member is formed on at least one of the two connecting portions of the cap and the bulb end to which the cap is fitted, and the rotation restricting member may be constituted as a holding member for restricting the rotation of the cap by holding the cap beyond scheduled angle.

According to this structure, the rotation restriction angle can be set in an accurate manner by the holding member.

The present invention also provides a fluorescent lamp, comprising:

A bulb formed by: connecting a plurality of straight pipe parts with an outer pipe diameter of 12-20mm in the same plane through a curved part; forming a pair of close ends in which electrodes are sealed so as to pass through the straight pipe parts and the curved parts partially forming a discharge path; forming a fluorescent layer on the inner surface of the bulb; and sealing the discharge medium including mercury; and

a lamp cap arranged on the end of the bulb;

Wherein at least one of the bent portions is formed on at least one of the curved portions the coldest portion will maximize cooling when lit.

With the fluorescent lamp according to the present invention, the coldest part is formed on the curved part of the bulb having a straight tube part with an outer tube diameter of 12-20 mm, so that by extending the distance from the electrode to the end of the bulb beyond a desired distance, it is possible to reduce The coldest part is ensured with a reduced discharge path, thereby further increasing the lamp efficiency.

According to the above fluorescent lamp, the maximum length of the inner tube diameter at the bent portion is preferably 1.2 times or more than the inner tube diameter of the straight tube portion.

The inner tube diameter on the curved part mentioned here refers to the inner diameter in the direction perpendicular to the central axis of the discharge path, and when the cross-sectional shape of the curved part in this direction is not a true circle, it means that the transverse The maximum width dimension within the section.

In order to form the coldest part, it is necessary to enlarge the so-called non-discharge region in which no discharge is formed. However, in the case of a straight pipe portion having an outer pipe diameter of 12-20 mm, it has been experimentally confirmed that by making the inner pipe diameter on the curved portion 1.2 times or more that of the straight pipe portion, it is possible to substantially guarantee The desired coldest part temperature, although this depends on the magnitude of the input electrical power. In addition, in order to further secure the coldest portion, the inner pipe diameter on the curved portion is preferably 1.5 times or more that of the straight pipe portion. Also, in consideration of the mechanical strength of the bent portion, the inner pipe diameter at the bent portion is preferably 2.5 times or less, more preferably 1.8 times or less, that of the straight pipe portion.

According to this structure, the coldest part is formed on the curved part of the bulb having the straight pipe part having an outer tube diameter of 12-20 mm, thereby ensuring the desired coldest part without reducing the length of the discharge path, and further Increased lamp efficiency.

The above-mentioned fluorescent lamp preferably emits light at a tube wall load of 0.05 W/cm ² or higher.

Here, the wall load refers to the lamp input electric power per inner surface area of the bulb, and the greater the wall load, the greater the heat emitted, so the bulb temperature tends to be higher. In addition, it should be noted that the term "inner surface area of the bulb" used herein does not mean the inner surface area of the entire bulb, but the inner surface area of the bulb in the region where the discharge path is formed.

At high bulb temperatures, the mercury vapor pressure inside the bulb rises above the optimum temperature and must form the coldest part in the bulb. In particular, in the case of a tube wall load of 0.05 W/cm ² or higher, experiments have shown that forming the coldest part according to the present invention makes the mercury vapor pressure suitable and further improves the lamp efficiency. This advantage becomes more pronounced at pipe wall loads of 0.1 W/cm ² or higher.

With this structure, the fluorescent lamp emits light under the tube wall load of 0.05W/ ^cm2 , and makes the mercury vapor pressure suitable and further improves the lamp efficiency.

According to the above fluorescent lamp, in the bent portion, the tip of an adjacent straight pipe portion may be formed to extend in the axial direction of the straight pipe portion and protrude onto the connecting portion.

By forming the bent portion so that the tip of the straight bulb protrudes to the connection position of the adjacent straight bulbs, this protruding area constitutes a non-discharge area of the protruding area, thereby forming the coldest portion. Thus, the desired coldest portion can be simply formed by protruding the tip of the straight bulb without forming the bent portion into a special shape.

According to this structure, by protruding the tip of the straight bulb, the coldest portion can be simply formed on the bent portion, thereby facilitating the formation of the bent portion.

The present invention also provides a fluorescent lamp, comprising:

Discharge vessel having a glass bulb formed by partially bending a glass tube having an outer tube diameter of 12-20 mm and a tube length of 800-3000 mm so as to form a plurality of straight tube parts arranged alternately adjacently in the same plane and The curved portion so that both ends provide straight pipe portions adjacent to each other so as to provide a polygonal shape as a whole, the glass bulb is provided with a pair of sealed thin tubes protruding from both ends of the glass bulb for exhaust, forming a fluorescent layer on the inner surface side of the glass bulb, a pair of electrodes sealed on the inner sides of both ends of the glass bulb, and a discharge medium sealed inside the glass bulb, and

Lamp caps arranged at both ends of the bulb.

According to the present invention, since the discharge medium is sealed after exhausting from a pair of thin tubes, exhausting can be performed well even if the polygonal shape is provided in a long and thin discharge vessel with an outer tube diameter of 12-20 mm and a tube length of 800-3000 mm . Therefore, residual impure gas in the discharge vessel can be reduced. Thus, the luminous flux maintenance factor of the fluorescent lamp can be improved.

With the fluorescent lamp described above, a part of at least one of the paired thin tubes is bent so that the paired thin tubes extend approximately parallel to each other.

With this structure, the manufacturing process of the present invention is easier. That is, according to the arrangement of the tip portions of the paired thin tubes in parallel, the paired thin tubes can be easily connected to the vacuum pump head, and the manufacturing equipment can be structurally simplified. In addition, the pair of thin tubes can be used for gas cleaning before venting. Furthermore, handling is facilitated when sealed in the discharge medium after degassing or evacuation.

The present invention also provides a method for manufacturing a fluorescent lamp with the above structure, comprising the following steps:

Form a discharge vessel with a straight tube shaped glass bulb, wherein the fluorescent layer is provided on the inner surface of a glass tube with an outer tube diameter of 12-20 mm and a tube length of 800-3000 mm, sealed at the end of the glass tube for supporting electrodes and having A pair of capillary electrode holders;

A shaped discharge vessel in which a straight tube shaped glass bulb is partially heated to soften and then bent so that a plurality of tube sections adjacent to each other and bent sections are alternately formed in the same plane so that the two ends constitute a straight tube section and adjacent to each other so as to provide the polygon as a whole;

After the step of forming the discharge vessel, venting the interior of the discharge vessel from a pair of thin tubes protruding from the ends of the glass bulb, followed by sealing the discharge medium and sealing the narrow tubes; and

Lamp caps are provided at both ends of the discharge vessel.

In the above method, the venting/sealing step is for venting the inside of the discharge vessel from a pair of thin tubes protruding from the end of the glass bulb after the forming step of the discharge vessel, and sealing the discharge medium and then sealing the thin tubes. tube steps. In this process, the degassing step is a step for simultaneously degassing from both ends of the discharge vessel through a pair of narrow tubes, that is, a step of vacuuming. An inert gas purge may be performed prior to the venting step. In this case, this washing step can be performed through a pair of narrow tubes.

Sealing of the discharge medium is performed by using one or both of the narrow tubes of the pair. Mercury vapor is sealed into the discharge vessel through a thin tube in either pure mercury or amalgam form.

After the inside of the discharge vessel is exhausted, a discharge medium is sealed therein. Next, the pair of narrow tubes is sealed by closing the valve of the tube connected to the device for sealing the discharge medium and heating the middle of the narrow tubes by means of a gas burner. In this way, the heated glass part is melted and cut off, and the molten tip part invades into the thin tube, which is then hardened due to the low pressure in the discharge vessel, becoming hard. Thus, it is possible to provide a structure in which the tips of the pair of thin tubes have inwardly protruding inner surfaces, which is a main feature of the present invention.

As described above, according to the present invention, since the discharge (evacuation) of the discharge vessel is simultaneously performed through a pair of thin tubes protruding from both ends of the glass bulb, it is possible even when the discharge vessel has a polygonal shape. Fully ensure exhaust. Thus, the luminous flux maintenance factor of the obtained fluorescent lamp can be improved.

In the above fluorescent lamp, the pair of narrow tubes preferably extend in a horizontal direction opposite to both sides of the bulb end, and then bend at a curved portion with a radius of curvature of 15-30 mm, whereby the tip portion passes straight upward.

The radius of curvature of the curved portion of the pair of narrow tubes is 15-30 mm, so that a mercury sealing medium such as mercury or amalgam inserted from the narrow tubes moves smoothly through the narrow tubes by its own weight.

Therefore, mercury can be quickly and safely sealed into the airtight container, and the efficiency of the sealing process is improved.

Furthermore, when the radius of curvature of the curved outer ends of the pair of narrow tubes is less than 15 mm, the degree of curvature of this bent portion is very close to a right angle, causing a further problem of difficulty in inserting mercury into the outer ends of the narrow tubes.

On the other hand, when the radius of curvature of the curved portion exceeds 30 mm, the vertical angle of the curved portion is a reverse obtuse angle. Accordingly, since the amount of expansion of the upright portion of the thin tube expanding toward the side of the sealed end of the airtight container is increased, this may lead to an increase in the gap between the paired sealed ends that do not emit light, causing a decrease in lamp efficiency. question.

However, according to the present invention, since the curved portion of the thin tube has a radius of curvature of 15-30 mm, this problem can be avoided in advance.

Furthermore, according to the fluorescent lamp of the present invention, it is desirable that the central axes of the horizontal portions of the pair of thin tubes extending in the horizontal direction toward the side of the bulb ends opposite to each other are arranged offset from each other.

According to this structure, the horizontal portions of the outer end portions of the pair of thin tubes (exhaust pipes) are constructed such that their central axes are offset from each other so as to extend near the sealed end portion and the horizontal portions of the outer end portions of the pair of thin tubes Not leaning on each other.

Accordingly, it is possible to prevent the gap between the pair of sealed end portions, which is a dark portion, from increasing while extending the length of the horizontal portion of the pair of thin tubes, thereby allowing the radius of curvature of the bent portion to become larger easily without increasing the dark portion .

In addition, the present invention also provides a lighting device, which includes: a lighting device main unit; a fluorescent lamp provided in the lighting device main unit and having the aforementioned structure; and lighting the fluorescent lamp by applying a high-frequency voltage of 10 KHz or higher thereto high frequency ignition circuit.

In the present invention, the term "lighting equipment" is a broad concept including all devices that use light emitted from the fluorescent lamps described in claims 1-3, including examples such as lighting fixtures, marker lights, display lights, advertising lights, and the like. In addition, the term "lighting device main unit" refers to the rest of the lighting device except the fluorescent lamp and the high-frequency ignition circuit. Allows lighting equipment to have a structure in which fluorescent lamps emit light in a space enclosed by parts such as light-transmitting balls or shades. However, a structure may be employed in which the fluorescent lamp emits light in a state of being exposed to the outside. Also, the high-frequency ignition circuit is a circuit device for lighting a fluorescent lamp with high frequency, and a switching device for high-frequency output may be provided as required. The switching device may have a structure capable of switching between a low-power mode for high-efficiency light emission of the fluorescent lamp and a high-power mode for high-output light emission of the fluorescent lamp, or a structure to continuously switch the modes between these modes. Switching of such a switching device for the ignition circuit regulates the lighting power of the fluorescent lamp.

The fluorescent lamps are fixed according to the shape of the lighting fixture main unit or the optical performance of the lighting fixture, and a plurality of fluorescent lamps of the same or different shapes are attached to the holder main unit in the same plane or at different heights.

Thus, according to the present invention, the above-mentioned high-frequency ignition of the fluorescent lamp can achieve lighting equipment that utilizes high-frequency lighting.

Description of drawings

Fig. 1 is a front view of a fluorescent lamp according to a first embodiment of the present invention.

2(a), (b), (c) and (d) are schematic diagrams for explaining a manufacturing process of the fluorescent lamp shown in FIG. 1 .

Fig. 3 is a front view of a fluorescent lamp according to a third embodiment of the present invention.

Fig. 4 is a front view of a fluorescent lamp according to a fourth embodiment of the present invention.

Fig. 5 is a front view of a fluorescent lamp according to a fifth embodiment of the present invention.

Fig. 6 is a front view showing a partial section of main parts of a fifth embodiment.

Fig. 7 is a graph showing the mercury vapor pressure characteristics of the main amalgam in the fifth embodiment and the comparative example.

Fig. 8 is a graph showing the mercury vapor characteristics of the main amalgam of the sixth embodiment of the present invention and a comparative example.

9 is a front view showing a positional relationship between a glass bulb and electrodes of a fluorescent lamp according to a seventh embodiment of the present invention together with a conventional circular fluorescent lamp.

Fig. 10 is a schematic diagram showing a main part of a fluorescent lamp in an enlarged size according to an eighth embodiment of the present invention.

FIG. 11 is an end view on a cutaway portion taken along line XI-XI in FIG. 10 .

Fig. 12 is also an end view showing a modification of the eighth embodiment.

Fig. 13 is a front view of a fluorescent lamp according to a ninth embodiment of the present invention.

FIG. 14 is an enlarged view of the bent portion shown in FIG. 13 .

Fig. 15(a) is a front view of a lighting device according to a tenth embodiment of the present invention, and Fig. 15(b) is a side view thereof.

Fig. 16 is a front view of a fluorescent lamp according to an eleventh embodiment of the present invention.

17( a ) and ( b ) are sectional views taken along line XVII-XVII in FIG. 16 .

Fig. 18 is an enlarged view of a main part showing the relationship between the bent portion of the straight tube shaped glass bulb - the burning width of the planned forming portion and the bent width thereof.

Fig. 19 is a front view of a fluorescent lamp according to a twelfth embodiment of the present invention.

Fig. 20 is a front view of a fluorescent lamp according to a first modification of the embodiment shown in Fig. 19 .

Fig. 21 is a front view of a fluorescent lamp according to a third modification of the embodiment shown in Fig. 19 .

22(a) is a front view of a fluorescent lamp according to a thirteenth embodiment of the present invention, and FIG. 22(b) is a partially enlarged view of an electrode sealing end of the fluorescent lamp of FIG. 22(a).

23(a)-(e) are front views of first to fifth modified fluorescent lamps according to the thirteenth embodiment of the present invention, respectively.

Fig. 24 is a schematic plan view showing a lighting fixture according to a fourteenth embodiment of the present invention.

25 is a front view of a lamp with wires in a state in which a base is removed, showing a partially enlarged sectional view of a fluorescent lamp according to a fifteenth embodiment of the present invention.

Fig. 26 is an enlarged sectional view of a tube end of the fluorescent lamp shown in Fig. 25 .

27(a), (b), (c), (d) and (e) are schematic diagrams showing steps for forming the discharge vessel of the fluorescent lamp shown in FIG. 25. FIG.

Fig. 28(a) is a partially cutaway schematic diagram of a discharge vessel before exhaust according to a sixteenth embodiment of the present invention, and Fig. 28(b) is a side view thereof.

Fig. 29(a) is a front view of a lamp with wires according to a seventeenth embodiment of the present invention, and Fig. 29(b) is a front view of a lamp with wires according to an eighteenth embodiment of the present invention.

Fig. 30 is an enlarged-sized side view of a pair of thin tubes and their peripheral portions according to a nineteenth embodiment of the present invention.

FIG. 31 is a plan view of FIG. 30 .

Fig. 32 is a schematic view showing the inclination angles of a pair of narrow tubes shown in Figs. 30 and 31 .

[reference mark]

2, 102, 112, 202... glass bulb; 2a, 102a... straight tube bulb; 2b, 102b, 202b... straight tube part; 2c, 101c, 201c... curved part; 2d, 102d, 202d...end; 1e, 201g, 201h...thin tube; 1f...lead wire; 3...protective layer; 4...fluorescent layer; 5, 105, 205...electrode; DV. ..discharge vessel; FL... fluorescent lamp; H... horn-shaped stem; M... electrode support.

Detailed ways

An embodiment of a ring-shaped fluorescent lamp and a lighting device according to the embodiment will be described below with reference to the accompanying drawings.

1 and 2 show a first embodiment of the present invention, FIG. 1 is a front view of a fluorescent lamp, and FIG. 2 includes schematic views for explaining a manufacturing process of the fluorescent lamp shown in FIG.

In the drawings, reference numeral 1 denotes a fluorescent lamp having a discharge vessel DV and a base 6 . The discharge vessel DV is constituted by a rectangular glass bulb 2 provided with a straight portion forming a substantially rectangular shape and having the following structure. That is, a discharge medium including an inert gas is sealed in a glass bulb. The inert gas is argon (Ar) gas, and is sealed at a pressure of about 320Pa. In addition to or instead of argon, other known discharge agents such as neon, krypton, xenon, etc. can also be used as the inert gas.

A protective layer 3 formed of fine particles of metal oxide is formed on the inner surface of the glass bulb 2 , and a phosphor layer 4 composed of three-wavelength emitting phosphor particles is formed on the inner surface of the protective layer 3 . The phosphor layer 4 is preferably coated with a 3-wavelength emitting phosphor. The fluorescent layer 4 has a correlated color temperature of 5000K, is used in an amount ranging from 4.0 to 7.5 mg/cm ² , preferably in a range of 4.0 to 6.0 mg/cm ² , and is formed into a film with a thickness of 20 μm by a drying/baking process. In addition, the coating amount of the protective layer is 0.6 to 0.8 mg/cm ² .

Although known phosphors such as 3-wavelength emitting phosphors, halo-phosphate phosphors, etc. may be used to constitute the phosphors forming the fluorescent layer 4, it is preferable to use 3-wavelength emitting phosphors from the viewpoint of emission efficiency.

Examples of such 3-wavelength emitting phosphors include (but are not limited to): BaMg 2 Al 16 O 27 :Eu 2+ as a blue phosphor with an emission peak wavelength around 450 nm, and BaMg ₂ Al ₁₆ O ₂₇ :Eu ²⁺ as a green phosphor with an emission peak wavelength at (La, Ce, Tb)PO ₄ having an emission peak wavelength of about 540nM, Y ₂ O ₃ :Eu ³⁺ having an emission peak wavelength of about 610nm as a red phosphor, and the like.

In addition, it should be noted that a known substance such as alumina (Al ₂ O ₃ ) or silica (SiO ₂ ) having a thickness of 0.5 μm or more is preferably used.

In addition, the protective layer may be formed to have a thickness of about 10-20 μm by using strontium phosphate (Sr ₂ P ₂ O ₇ ) fine particles having an average particle diameter of about 2.5 μm.

The glass bulb 2 has four straight tube parts 2b and three curved parts 2c, and the four straight tube parts 2b are connected in substantially the same plane so as to form sides of a rectangle. Furthermore, it is desirable that the glass bulb 2 has a length L. As shown in FIG. One side thereof is preferably 200mm or longer, and in this example, the length L is about 300mm. Both end portions 2d of the glass bulb 2 are arranged close together, and filament electrodes 5 and 5 formed of triplet coils coated with an emitting substance are sealed at the end portions 2d. The electrodes 5 and 5 are supported by a pair of lead wires that are preliminarily sealed to a flared stem (not shown) so as to provide electrode holders, and the filament electrodes 5 and 5 pass through the ends 2d sealed in the glass bulb 2. The electrode holder is sealed inside the bulb. An exhaust thin tube 2f is fixed to the flared stem, and amalgam 2g for controlling mercury vapor pressure is stored in this thin tube 2f.

The outer diameter of the straight pipe portion 2b is 12-20mm, the wall thickness of the pipe is 0.8-1.5mm, preferably 0.8-1.2mm, and in the case of the present embodiment, the inner diameter is about 16mm and the wall thickness of the pipe About 1.2mm. The insides of the respective straight pipe portions 2b are communicated via the bent portion 2c to form a discharge path so as to surround the center of the rectangle formed by the straight pipe portions 2b between the pair of electrodes 5 and 5 .

The base 6 is mounted on both end portions 2b of the glass bulb 2 so as to straddle both end portions 2d. The base 6 is provided with a power supply unit 6a constituted by four pins and electrically connected to a pair of electrodes 5 and 5. As shown in FIG. The fluorescent lamp 1 has three curved portions 2c formed at three diagonal positions of a rectangle formed by the straight tube portion 2b of the glass bulb 2, and the base 6 is disposed at the remaining one diagonal position.

The curved portion 2c has approximately the same cross-sectional shape as the straight pipe portion 2b. The cross-sectional shape of the bent portion 2c may be approximately triangular or square. In the case where the bent portion 2c has a shape protruding outward, a discharge path is formed inside. This case indicates that the non-discharge area is large, and the coldest part with a high cooling effect can be realized, and temperature characteristics can be improved even without an amalgam for controlling mercury vapor pressure.

2(a)-(d) are schematic diagrams for explaining the manufacturing method of the glass bulb 2 of the fluorescent lamp 1 constructed as above. In the manufacturing method of this glass bulb 2, as shown in FIG. A column (not shown) mounts the electrodes 5 and 5 inside the bulb 2, and utilizes the exhaust pipe 2f at one of the end portions 2d and 2d for introducing a pair of lead wires.

The pair of electrodes 5 and 5 is formed by a hot cathode with a filament coated with an emitting substance, but other electrodes can also be used instead. Furthermore, triplet coils are preferred for hot cathodes where high output lighting performance is required for the lamp. In addition, the lead wires supporting the electrodes 5 and 5 can be sealed and supported by components such as twist stems, bead stems, press seals and the like. In addition, a stem or the like may be fixed to a thin tube for exhausting or for storing amalgam.

The straight tube shaped bulb 2a has an overall length of 1200 mm and includes three bent portions-forming predetermined portions 2e (ie, portions 2e will be formed as bent portions later). The lengths l ₁ , l ₂ and l ₃ of the predetermined portion 2e are each approximately 90mm, and the total length of the three predetermined portions 2e is 270mm, which is approximately 23% of the total length of the straight bulb 2a.

As shown in Figure 2 (a), at first, use the gas burner B to heat and soften the curved part-form the predetermined part 2e, and as shown in Figure 2 (b), carry out the bending process so that the gap between the adjacent straight pipe parts 2b The angle is approximately 90 degrees, and then, the first bent portion 2c is formed into a predetermined shape by a molding process or the like. Next, the bent portion adjacent (continuously) to the first bent portion 2c is heated and softened with the gas burner B-forming the predetermined portion 2e, and subjected to bending and molding processing, thereby forming the second bent portion 2c, As shown in Figure 2(c). Finally, the bent portion adjacent to the second bent portion 2c is heated and softened with a gas burner B to form a predetermined portion 2e, and it is subjected to bending and molding processing, thereby forming a third bent portion 2c, as shown in FIG. 2( d) as shown. Then, the bulb is exhausted from the exhaust pipe 2f, and mercury is sealed therein, whereby the glass bulb 2 is completed.

Although the bent portion 2c is formed by bending work, it is not necessary to additionally heat the portion of the straight tube shaped bulb 2a other than the bent portion-forming predetermined portion 2e, so that even in the case where the fluorescent layer 4 is applied before the bent portion 2c is formed, Thermal degradation of the phosphor does not easily occur, and there is an advantage of significantly improving the luminous flux maintenance factor. These advantages become more apparent when the total length of the curved portion-forming predetermined portion 2e is 50% or less, preferably 30% or less and most preferably 20% or less of the total length of the straight tube shaped bulb 2a.

The fluorescent lamp 1 can take the following dimensions. For a fluorescent lamp 1 equivalent to a conventional 30W type annular fluorescent lamp, the glass bulb 2 is formed with a total length L of 225mm, a maximum width on the inner side of 192mm, an outer tube diameter of 16mm, and a wall thickness of the glass bulb 2 of 1.0mm. The rated lamp power of the fluorescent lamp was 20W, and when the lamp was lit, the high output performance lamp power was 27W. For a fluorescent lamp 1 equivalent to a conventional 32W type annular fluorescent lamp, the glass bulb 2 is formed with a total length L of 299 mm, a maximum width on the inside of 267 mm, an outer tube diameter of 16 mm, and a wall thickness of the glass bulb 2 of 1.0 mm. The rated lamp power of the fluorescent lamp was 27W, and when the lamp was lit, the high output performance lamp power was 38W. For a fluorescent lamp 1 equivalent to a conventional 40W type annular fluorescent lamp, the total length L of the glass bulb 2 is formed to be 373 mm, the maximum width on the inner side is 341 mm, the outer tube diameter is 16 mm, and the wall thickness of the glass bulb 2 is 1.0 mm. The rated lamp power of the fluorescent lamp is 34W, and when the lamp is lit, the high output performance lamp power is 48W.

The fluorescent lamp of this embodiment will work as follows. The high-frequency electric power input is delivered to the fluorescent lamp 1 through the power supply part 6a of the lamp cap 6, and the fluorescent lamp is ignited by the low-pressure mercury vapor discharge in the bulb 2. The fluorescent lamp 1 is lit with a lamp input power of 20 W or higher, a lamp current of 200 mA or higher, a tube wall load of 0.05 W/cm 2 or higher, and a lamp efficiency of 50 lm/W or higher. Further, as the lamp current per cross-sectional area of the straight tube portion 2b, the lamp current density was 75 mA/cm ² or higher. In the case of this embodiment, the lamp input power was 50W, the lamp current was 380mA, and the lamp efficiency was 90lm/W.

The amalgam can be sealed in the bulb 2. For example, in order to seal a predetermined amount of mercury, an amalgam such as zinc-mercury may be sealed. By enclosing an amalgam for controlling mercury vapor in the bulb, the ambient temperature becomes relatively high, and the fluorescent lamp is lit optimally.

The amalgam can take any shape such as pellets, cylinders, plates, etc. The amalgam is stored in a thin tube placed on a stem sealed to the end of the bulb and inside the bulb 2 . The amalgam is fixed or stored in one of the aforementioned locations by melting, mechanical fixing, or the like. Furthermore, the amalgam can be stored in the bulb to be removable therein.

When the fluorescent lamp 1 is turned on, the temperature of the bulb 2 rises to about 80°C. However, in the present embodiment, a bismuth (Bi)-tin (Sn)-lead (Pb) amalgam is stored in the thin tube 2f, so that the vapor pressure in the bulb is controlled on the basis of the pressure characteristic of the mercury vapor of the amalgam. To an appropriate value, correspondingly, the lamp can be lit with high efficiency.

In addition, although in the present embodiment, the glass bulb 2 is formed by partially bending a straight tube-shaped bulb 2a, in an alternative manner, the ends of two bulbs may be connected in an L shape so as to form a bent portion and Form the glass bulb 2.

The glass bulb 2 is formed of soft glass such as soda lime glass, lead glass, etc., but hard glass such as borosilicate glass or quartz glass may also be used. In addition, glass that substantially does not contain a lead component, includes 1.0% by mass or less of sodium oxide, and has a softening temperature of 720° C. or less may be used. The disclosure of "substantially no lead component" means that inclusion of a trace amount of lead as an impurity, preferably 0.1% by mass or less, may be tolerated. Most preferably, of course, the glass does not contain lead components. The case where sodium oxide is included in an amount of 0.1% by mass or less includes the case where no sodium oxide is included. Also, the reason for including 0.1% by mass or less of sodium oxide is that, if its content exceeds the above value, deposition of sodium oxide components on the inner surface of the glass bulb 2 affects the light output of the fluorescent lamp 1 . In substantially lead-free glass, wherein the glass has a sodium oxide content of 1.0% by mass and a softening temperature of 720°C or less, the amounts of _K2O and _Li2O and CaO, MgO, BaO, and SrO may be present in the content Make adjustments. Here, the softening temperature is where the glass viscosity η = 10 ^7.65 dPa·s.

When the amount of sodium oxide in the glass bulb 2 exceeds 0.1% by mass, then a large amount of sodium is deposited on the inner surface of the glass bulb 2 as an alkali component during lighting of the lamp. In the case where sodium is deposited on the inner surface of the glass bulb 2, the following problems may occur: the sodium may react with the mercury vapor sealed in the glass bulb 2, the glass bulb 2 may be colored, and the transmittance of visible light may decrease, or the sodium may It reacts with the phosphor in the phosphor layer 4 to degrade the phosphor and reduce the output power of visible light. In particular, since conventional soda-lime glass contains 15-17% by mass of sodium oxide, a decrease in visible light output will be significantly observed.

Accordingly, by applying phosphor to the straight bulb 2a formed of glass containing 0.1% by mass or less of sodium oxide and having a softening temperature of 720° C. The amount of sodium on the inner surface of the bulb, in addition, can suppress the drop in visible light output due to the sodium reaction. In addition, since the softening temperature is 720°C or less, the heating temperature when forming the bent portion can be kept low, thus reducing degradation of the surrounding phosphor while increasing light output performance.

The composition of the glass bulb according to this embodiment is as follows, and the softening temperature is 692°C.

SiO ₂ : 65.0 mass%, Al ₂ O ₃ : 4.0 mass%, Na ₂ O: 0.05 mass%, K ₂ O: 11.0 mass%, Li ₂ O ₃ : 2.8 mass%, CaO: 2.0 mass%, MgO: 1.4 % by mass, SrO: 5.0% by mass, BaO: 8.5% by mass, SO ₃ : 0.15% by mass, B ₂ O ₃ : 0% by mass, Sb ₂ O ₃ : 0% by mass, Fe ₂ O ₃ : 0.03% by mass, remainder Amount: 0.17% by mass.

Next, a second embodiment of the present invention will be described. In this second embodiment, the metal oxide constituting the protective layer 3 has an average particle diameter of about 5.0-50 nm, a surface area of 80 m ² /g or more, and the amount of fine particles applied per surface area in the bulb is 0.01 -0.1 mg/cm ² .

In the case of the second embodiment, even if the amount of the applied protective layer 3 is reduced and its film thickness is also reduced, the straight pipe portion 2b does not substantially stretch, and the fluorescence of the straight pipe portion 2b in the bent portion forming step Thermal degradation of layer 4 is minimal. Furthermore, since the thickness of the protective layer 3 is small, the function of the protective layer 3 can be sufficiently exhibited while suppressing the occurrence of cracks on the bent portion 2b. In addition, the fine particles have a specific surface area of 80 m ² /g or more, so the protective layer 3 is an extremely compact structure, and thus the alkali components and mercury, etc. deposited from the bulb 2 are blocked by the protective layer 3, whereby fluorescence can be effectively suppressed Degradation of layer 4 and coloration of bulb 2 over time.

Fig. 3 is a front view showing a fluorescent lamp 1A according to a third embodiment of the present invention. This embodiment is the same as the first embodiment, except that the rectangular glass bulb 2 is composed of five straight pipe portions 2b and four curved portions 2c formed in the diagonal direction thereof and is provided on an approximately central portion on one side of the bulb 2. The lamp cap 6 is formed outside.

Fig. 4 is a front view showing a fluorescent lamp 1B according to a fourth embodiment of the present invention. The present embodiment has a base 6B which is arranged to bridge the two ends 2d and 2d of the glass bulb 2 on opposite sides. A base pin 6a serving as a power supply portion is provided at the center of the rectangular shape of the bulb 2. As shown in FIG. In addition, a lamp fixing mechanism is provided near the power supply unit, which is to be mounted on the lamp holder side of the lighting device and is not shown in the figure, so that the electrical connection is established while the lamp is mounted on the lighting device. By forming the base 6B in this way so as to bridge the two opposite sides of the square, the bulb 2 can be supported more stably and the fixing strength can be improved, while the strength of the bulb 2 itself can be improved. Furthermore, by arranging the power supply unit at the approximate center of the square, lamp balance can be improved when the bulb 2 is mounted, thereby facilitating its replacement operation.

5-7 show a fluorescent lamp 1C according to a fifth embodiment of the present invention, wherein FIG. 5 shows a front view, FIG. 6 shows a front view of a partial cross section of an arrangement of main parts, and FIG. 7 shows the mercury of the main amalgam together with its comparative example. Curves of vapor characteristics.

This embodiment differs from the above embodiments in that the inner diameter of the curved portion 2c of the glass bulb 2 is set to a predetermined size, an amalgam 2g having predetermined characteristics of mercury vapor is used, and the length of the exhaust capillary is set within a predetermined range.

That is, when heat softens and bends a predetermined portion of the curved portion 2c for the glass bulb 2, the curved portion is shaped by using molding, and the inner diameter of the curved portion 2c of the glass bulb 2 is set at 0.6 of the inner diameter of the straight pipe portion 2b. In the range of -1.0, that is, 0.86 times in the figure. In addition, the exhaust thin tube 2f protruding from the outside of the stem 2h at one end of the glass bulb 2 has a protruding length of 10mm or more, and the coldest part is formed at its tip. Furthermore, the protective layer existing between the glass bulb 2 and the fluorescent layer 4 is not shown in the figure.

The inner diameter of the bent portion 2c is measured on the cross section of the bent portion 2c. If the cross-sectional shape of the bent portion 2c is non-circular, the inner diameter is determined on the portion having the largest pipe diameter. In the case where the inner diameter of the bent portion 2c is smaller than 0.6 of the inner diameter of the straight pipe portion, the temperature of the bent portion 2c rises. However, this is undesirable because the arc is squeezed at the bent portion 2c, causing the lamp voltage to rise, so that the lamp power is input too much, and the mercury injected into the phosphor layer 4 increases, eventually causing the phosphor layer to be more easily degraded. In addition , if the inner diameter of the bent portion 2c exceeds 1.0 of the inner diameter of the straight pipe portion, it is not favorable and desirable because the temperature of the bent portion 2c drops and the coldest portion is easily formed there. On the other hand, by setting the inner diameter of the curved portion 2c of the bulb within a range of 0.6-1.0 times the inner diameter of the straight pipe portion 2b, the temperature of the curved portion 2c becomes substantially the same as that of the straight pipe portion 2b.

As shown in FIG. 6, the amalgam is formed of main amalgam 2g and auxiliary amalgam 2i. According to the mass ratio, the main amalgam 2g contains the following components: 40-50% Bi, 15-35% Pb, 15-40% Sn, and 6% or more of Hg, mercury vapor is introduced into the inside of the glass bulb 2 to seal it and held in the exhaust thin tube 2f. In addition, the main amalgam 2g contained 9% by mass of mercury within the above composition range and had mercury vapor pressure characteristics as shown in FIG. 7 .

The auxiliary amalgam 2i is composed of In or Au deposited on a stainless steel substrate and is provided by welding the substrate at a position near the electrode 5 of the inner lead 2j on the power supply side at the time of lighting.

8 is a graph showing mercury vapor characteristics of a main amalgam of a fluorescent lamp according to a sixth embodiment of the present invention together with a comparative example.

In this embodiment, the composition of the main amalgam 2g is different from that of the fifth embodiment, that is, according to the mass ratio, the main amalgam 2g contains the following composition: 50-60% Bi, 45-50% Pb, 0-3% In, 3-5% Hg. In addition, the main amalgam 2g exhibits changes in mercury vapor pressure characteristics depending on the content of In, as shown in the figure.

By heating the end of the bulb and/or forming a neck in the path of the thin tube so as not to let the main amalgam 2g fall in the thin tube, the main amalgam 2g can be melted and fixed in the annular molded part so as to be formed into end face of the bulb.

In addition, when the temperature of the bulb 2 portion near or on the outer surface of the thin tube is 50°C, it is desirable that the main amalgam 2g has a mercury vapor pressure in the range of about 0.13 to 1.1 Pa.

9 is a front view showing the main part of the fluorescent lamp of the present embodiment and, for comparison, the positional relationship between the glass bulb and the electrodes of the fluorescent lamp of the seventh embodiment together with the conventional circular fluorescent lamp (left side view in FIG. 9 ). .

In this embodiment, instead of the mercury vapor pressure controlling amalgam, the height H _M of the electrode 5 arranged on the side of the pipe end on the exhaust side is set within the range of 30-50 mm, for example, 40 mm, so that The coldest part is formed on the edge part. In addition, in the present invention, the electrode 5 is provided on the portion facing the straight pipe portion 2b of the glass bulb 2, so that the distance between the glass bulb and the inner surface and the electrode 5 becomes larger than that of the ring fluorescent lamp, so as shown in FIG. 9, it can be seen that the electrode 5 is not easy to contact with the fluorescent layer of the tube wall. In addition, in FIG. 9, reference numeral 2g denotes a zinc amalgam for sealing of a predetermined mercury amount, and the fluorescent layer is omitted from the figure for convenience of explanation.

Also, since the coldest part of the glass bulb 2 has a large height, the coldest part of the glass bulb 2 is formed in the annular molded part 2k (near the amalgam 2g) near the sealing part on the pipe end side on the exhaust side. on, or on the front end portion of the thin exhaust pipe 2f.

10 is an enlarged front view of the base 6 of a fluorescent lamp 1D according to an eighth embodiment of the present invention together with its surroundings, and FIG. 11 is an end portion taken along line X1-X1 in FIG. 10 .

The present embodiment differs from the preceding embodiments in that a rotation restricting member is provided for preventing rotation of the base 6D about the tube axis relative to the ends 2d and 2d of the glass bulb 2, the base 6D being formed of, for example, a plastic material so as to be externally fitted to On both axial ends 2d and 2d of the glass bulb 2, a pair of electrodes 5 and 5 are sealed in the glass bulb 2.

That is, in the fluorescent lamp 1D shown in FIG. 10, a pair of electrodes 5 and 5 are sealed in both axial end portions 2d and 2d of the glass bulb 2, and a pair of inner lead wires 2j and 2j connected to both end portions of the electrode 5 Protrude from both end portions 2d and 2d of the glass bulb 2 in an airtight manner, and the front portions of the outer leads 2ja and 2ja as the outer ends thereof are fixed to the inner front portions of the cap pins 6a of the cap 6D.

The glass bulb 2 has both end portions 2d and 2d that are flatly pressed into the pinch portion 2p, and a pair of outer leads 2ja and 2ja protrude outside the both end portions 2d and 2d in an airtight manner, thereby being hermetically sealed in an airtight manner. The inner lead 2j, and the pinch portion 2p are formed into a flat shape by molding.

As shown in FIG. 11, the lamp cap 6D has engaging protrusions 6x and 6y of a plastic lamp cap main unit 6b in the form of a cylindrical member which can be divided into two parts, namely a top and a bottom, so as to be fitted to the pinch part 2p from the outside. on both sides.

According to this arrangement, it is possible to prevent the base 6D from rotating around the tube axis with respect to the glass bulb 2, thereby preventing the outer lead wire 2ja from breaking, preventing the pair of outer lead wires 2ja and 2ja from contacting each other, and preventing the ignition circuit (not shown) from being damaged due to a short circuit and the glass bulb. Both ends 2d and 2d of the bulb are damaged.

That is, in the case where the base main unit is rotated about the tube axis, as in the base of a conventional annular fluorescent lamp, since both ends of the outer lead 2ja are fixed to each pinch portion 2p and the inner front end of the pin 6a of the base 6D , the outer lead wire 2ja may be pulled out or twisted by the rotation of the lamp cap 6, causing it to break and damage the pinch portion 2p. On the contrary, adjacent outer leads 2ja may contact each other and cause a short circuit, thereby damaging the ignition circuit.

However, according to the fluorescent lamp 1D of the present embodiment, since the cap main unit 6b hardly moves relative to the glass bulb 2 due to the provision of the rotation restricting member, the problem concerning the cap encountered in the prior art described above can be effectively solved.

Fig. 12 is a sectional view of another modified example of the rotation restricting member of the base 6D. The rotation restricting member allows the base 6D to rotate 45 degrees in forward and reverse directions around the tube axis, in which a plurality of outwardly facing holding protrusions 2m protrude by means of glass frit or the like on the outer peripheral surfaces of both end portions 2d, which have a substantially circular axial direction. cross-sectional shape, and its central angle is approximately a right angle. In this modification, it is not necessary to form the pinch portion 2p, as shown in FIG. 10, and can be used for a bulb end portion 2d using a flared stem, as shown on the right side in FIG.

On the other hand, on the inner peripheral surface of the fitting hole 6cb of the cap, a pair of inwardly facing retaining protrusions 6e and 6e are integrally provided in an upright manner at opposite positions in the diametrical direction, and these protrusions face toward both edges of the glass bulb. The central side of the fitting hole of the middle portion of the circumference between a pair of protrusions 2m adjacent in the circumferential direction of the portion 2m protrudes.

Accordingly, the base 6D is rotated by 45 degrees in the clockwise direction (forward direction) with respect to the glass bulb 2 , and on the other hand, is also rotated by 45 degrees in the counterclockwise direction (reverse direction). However, in this case, it is necessary to provide the outer leads 2ja and 2ja with a sufficient length so that the outer leads 2ja and 2ja will not be pulled out and broken or not to damage the pinch portion 2p when rotation occurs, and must also Parts and the like for preventing electrical connection between the external leads 2ja and 2ja are provided.

According to this lamp base 6D, the lamp base 6D can be rotated by 45 degrees in each of the forward direction and the reverse direction with respect to the glass bulb 2 around the tube axis, so that after fixing the glass bulb 2 to the lamp holder of the lighting equipment main body, by Rotating the lamp head 6D can widen the range in which the lamp head can be mounted to the power socket fixed to the lighting equipment. In addition, it should be noted that it is not necessary to limit the rotation angle of the lamp head 6D in the forward direction and the reverse direction to 45 degrees, and the positions of the outward-facing holding protrusion 2m and the inward-facing holding protrusion 6e are appropriately changed according to the situation. Make a selection.

Fig. 13 is a front view of a fluorescent lamp 1E according to a ninth embodiment of the present invention, and Fig. 14 is an enlarged view of a bent portion thereof.

In the present embodiment, in the case where the radius of curvature of the curved portion of the glass bulb 2 is too small, the outer side of the curved portion 2c is stretched too much and becomes too thin, thereby easily breaking. Thus, the present embodiment is characterized in that the radius of curvature of the curved portion 2c and the wall thickness are secured to predetermined values, thereby enhancing the intensity of the fluorescent lamp 1E.

As shown in FIG. 14, the curved portion 2c is formed such that the center O of the curvature radius r1 of the inner side surface 2c1 and the center O of the curvature radius r2 of the outer side surface 2c2 are located substantially at the same position. The inner side surface 2c1 of the curved portion 2c represents the surface facing the center portion of the virtual annular surface formed by the glass bulb 2, and the outer side surface 2c2 of the curved portion 2c represents a surface position different from the inner side surface 2c1 on the curved portion 2c by 180 degrees, where the tube The axis is located at the center therebetween (ie, the surface facing the direction extending parallel to the radial direction from the center portion of the annular plane formed by the glass bulb 2 ).

The radii of curvature r1 and r2 are defined by the curves formed at the positions where the inner and outer surfaces 2c1 and 2c2 intersect the virtual annular plane formed by the glass bulb 2 when the glass bulb is viewed from a direction perpendicular to the virtual annular plane formed by the glass bulb 2 , can be defined by the radius of curvature of the inner and outer contour lines formed in the curved portion 2c. The preferred range of the curvature radius r1 is 10-30 mm, and the preferred range of the curvature radius r2 is 25-55 mm. On the other hand, in this embodiment, the curvature radius r1 is 15 mm, and the curvature radius r2 is 31.5 mm. Further, in order to increase the strength of the bent portion 2c, the wall thickness t2 on the outer side surface 2c2 and the wall thickness t1 on the inner side surface 2c1 of the bent portion 2c are made 0.5mm or thicker by bending work. Furthermore, with the bulb 2 having the full length L, the stress applied to the curved portion 2c increases and the glass expansion ratio on the outside of the glass will also increase, so that the thickness on the curved portion must also be increased in order to secure mechanical strength. Experiments conducted on the basis of the above facts show that the strength of the bent portion 2c can be ensured by adjusting the wall thickness t0 of the straight pipe portion so as to satisfy the equation:

0.36(L/r1)≤t0≤0.2(L/r1).

Further, the tube diameter Dc of the curved portion 2c is formed approximately the same as the tube diameter Db of the adjacent straight tube portion 2b. By thus forming the curved portion 2c, the external view of the curved portion 2c of the annular bulb 2 is constituted, and a curve continuous with the straight pipe portion 2b is provided, so that the visual appearance of the arc tube 2 can be improved. In addition, since the low temperature portion is not partially formed at the time of light emission, the coldest portion is not easily formed, and black spots or strain due to aggregation are not easily formed on the bent portion 2c.

Furthermore, in the lamp of the present embodiment, both the diameter Dc of the curved portion 2c and the tube diameter Db of the straight tube portion 2b are 16.5 mm. The length l of the straight pipe portion 2b is 237 mm.

According to the present embodiment, the wall thicknesses of the curved portion 2b and the straight pipe portion 2b are thus prescribed to predetermined values so that the level of withstand vibration intensity assumed to be encountered in normal use of the fluorescent lamp 1 can be secured.

Fig. 15 shows a lighting device according to a tenth embodiment of the present invention, wherein Fig. 15(a) is a front view and Fig. 15(b) is a side view thereof.

The present embodiment relates to a lighting apparatus using one of the fluorescent lamps 1 and 1A-1E (for example, the fluorescent lamp 1 ) according to the first to ninth embodiments described above. The fluorescent lamp 1 is connected to a socket 11 of an apparatus (main) body 10 and mounted to a lamp holder 12 formed of a spring having a shape following one side of the bulb. A pyramid-shaped white reflective member 13 having a quadrangular pyramid shape is provided on the central portion of the fluorescent lamp 1 and fixed to the apparatus main body 10 . The reflective member 13 is formed to have a hollow structure and stores a light emitting device and the like therein. The reflective member 13 can be fixed directly to one side of the lamp 1 .

Since the lighting device according to the present invention has the quadrangular pyramid-shaped reflective member 13 disposed on the center of the square fluorescent lamp 1, high reflective efficiency in the downward direction from the device holder can be achieved and luminous efficiency can also be improved.

Figures 16 and 17 represent an eleventh embodiment of the present invention, wherein Figure 16 represents a front view of a fluorescent lamp, and Figures 17(a) and 17(b) represent an enlargement in a section taken along line XVII-XVII in Figure 16 A cutaway view of the scale's main parts.

In the drawing, reference numeral 101A denotes a fluorescent lamp having a rectangular glass bulb 2, which is basically formed into a square shape by a straight portion. A discharge medium consisting of an inert gas and mercury is sealed in the glass bulb 102 . The inert gas is argon (Ar) sealed at a pressure of about 320 Pa.

A protective layer 103 of about 1.0 μm thick is formed on the inner surface of the glass bulb 102, and is composed of aluminum oxide (Al ₂ O ₃ ) fine particles serving as metal oxide fine particles, and is formed on the inner surface of this protective layer 103 Phosphor layer 104 composed of fine particles of 3-wavelength emitting phosphors. The phosphor layer 104 is formed of 3-wavelength radiation phosphor fine particles with a correlated color temperature of 5000K, and applied in an amount ranging from 4.0 to 6.0 mg/cm ² , and then formed by drying and sintering processes so as to have a thickness of 20 μm.

The glass bulb 102 has a circular cross-sectional shape with four straight tube parts 102b and three curved parts 102c so that the four straight tube parts 102b are continuously arranged in the same plane to form a square side. Generally, it is preferable that the length of one side of the glass bulb 102 is 200 mm or more, and in this embodiment, the length 1 is about 300 mm. Both end portions 102d of the glass bulb 102 are disposed close to each other, and filament electrodes 105, 105 formed of triplex coils coated with emissive substances are respectively disposed on the both end portions 102d.

Generally, the inner diameter of the straight pipe portion 102b is preferably 12-20mm, and the thickness of the pipe wall is 0.8-1.5mm. In this embodiment, the inner diameter is about 16mm, and the thickness of the pipe wall is about 1.2mm. The insides of the respective straight pipe portions 102b communicate with each other through bent portions 102c in such a manner as to form a discharge path so as to surround the center of a generally square shape formed by the straight pipe portions 102b between a pair of electrodes 105 and 105 .

The base 106 is mounted on both end portions 102d and 102d of the glass bulb 102 so as to straddle the end portions 102d and 102d. The lamp base 106 has a power supply part 106a formed of four pins electrically connected to a pair of electrodes 105 and 105 . The fluorescent lamp 101 has three bent portions 102c formed on a portion on a diagonal of a square shape, and the base 106 is provided on the remaining other portion on the diagonal.

Fig. 17 is a cross-sectional view showing a curved portion 102c, wherein the cross-sectional view of Fig. 17(a) has a substantially isosceles triangular shape whose apex 102c1 protrudes outward from a plane formed by four straight pipe portions 102b, and Fig. 17 ( The cross-sectional view of b) has a substantially isosceles triangular shape with its vertices 102c1' protruding outward. The inner pipe diameter (maximum diameter) of the curved portion 102c corresponds to the height of the isosceles triangle having the apex 102c1 of the curved portion 102c. The inner pipe diameter D1 is formed to be 1.2 to 2.0 times the inner pipe diameter of the straight pipe portion 102b. In this embodiment, the inner diameter of the straight pipe portion 2b is about 13.6mm, and the inner pipe diameter D1 on the curved portion 102c is about 27.2mm, which is substantially twice the inner diameter of the straight pipe portion 102c. In addition, it should be noted that the minimum width 6 of the inner pipe diameter is substantially the same as the length in the direction of the base of the isosceles triangle, that is, the cross-sectional shape of the curved portion 102c, which is 13.6 mm, is the same as that of the inner pipe of the straight pipe portion 102b. same diameter.

The wall thickness of the curved portion 102c is preferably the same as or greater than that of the straight pipe portion 102b in order to maintain the mechanical strength of the curved portion 102c. Particularly, in the case of Fig. 17 (a), the wall thickness of the apex 102c1 tends to become thinner because the cross-sectional shape of the curved portion 102c is approximately an isosceles triangle shape, and thus, the thickness is preferably 1/3 of the thickness of the straight pipe portion 102b. 0.8-1.2 times.

Utilizing the bent portion 102c in which the bottom edge 102c1' protrudes outward, as shown in FIG. 17(b), since the discharge channel is formed inside, the non-discharge area can be formed to be large, thereby providing a high cooling effect and optimum the coldest part.

The operation of this embodiment will be described below. The fluorescent lamp 101A (1) to which high-frequency power is input through the lamp cap 106 is lit by the discharge of low-pressure mercury vapor in the bulb 102, and the fluorescent lamp 101A is lit with the following parameters: the lamp input power is 20 W or higher, and the lamp current is 200 mA or higher. Higher, the tube wall load is 0.05W/cm ² or above, and the lamp efficiency is 50lm/W or above. In addition, the lamp current density as the lamp current per cross-sectional area of the straight tube portion 102b is 75 mA/cm ² or more. In the case of this embodiment, the lamp input power is 50W, the lamp current is 380mA, and the lamp efficiency is 90lm/W.

When lighting the fluorescent lamp 101A, the coldest portion is formed onto at least one bent portion 102c. In the present embodiment, although the outer surface temperature of the straight pipe portion 102b is 80°C when the glass bulb 102 is lighted in a state where it is exposed to an ambient temperature of 25°C, the temperature of the apex 102c1 of the bent portion 102b is 50°C. It is believed that the coldest part is formed on this vertex 102c1. The outer surface temperature of the apex 102c1 in the range of 40-65°C is suitable for the coldest part, and if the mercury vapor pressure inside the fluorescent lamp 101A is optimal, the lamp can be burned with high lamp efficiency as long as the coldest part is within the above temperature range. light up.

Furthermore, although the glass bulb 102 is formed by partially bending one straight tube shaped bulb 102a in the present embodiment, a plurality of straight tube shaped bulbs may be connected at the ends, thereby forming the bent portion of the glass bulb 102. For example, a plurality of straight tube-shaped bulbs may be connected to provide connection portions by locally heating and melting their ends, followed by air blowing, which are then connected and molded into the bent portion 102c of a desired shape.

Fig. 18 shows the case of locally heating and melting a long straight tube shaped bulb 102a and forming a plurality of bent portions 102c to obtain a square shape, as shown in Fig. 16, in this case, the straight tube shaped glass bulb 102a is shown The mutual dimensional relationship between the heating width, that is, the burning width x, and the bending (curve) width c of the bending portion 102c.

As shown in FIG. 18, the bending width c is the length required for forming the coldest portion on the outer curved pipe wall 102C0 of the curved portion 102c, and represents the length from the coldest portion C0 formed on the curved outer pipe wall 102C0 to the radially opposite The length of the center of the outer surface of the curved inner pipe wall 102Ci. The length of the burning width x of the straight tube shaped bulb 102a is affected by the length of the bent width c, and the width dimension W on the inner side of the bent portion (in the direction perpendicular to the length of the bent width c and parallel to the longitudinal direction of the straight tube portion The length above) decreases proportionally to the burn width x.

That is, in the case of locally heating and softening a long straight tube-shaped bulb 102a provided with the protective layer 103 and the fluorescent layer 104, wherein these film layers are formed in advance, and then bending the bulb 102a at a predetermined angle to obtain a square shape, The glass bulb 102b expands and contracts at the bent portion 102c, and this expansion and contraction together peel off and crack the protective layer 103 and the fluorescent layer 104, causing factors that degrade the luminous flux on these portions, so it is desirable to make the width dimension W and the burning width x is as small as possible.

Furthermore, in the case of the same lamp current, the temperature of the coldest point C0 of the bent portion 102c depends on the bent width c.

Accordingly, in order to obtain the optimum coldest point temperature at this coldest point C0, the bending width c is set to be longer than the outer diameter d of the straight-tube-shaped bulb 102a, and the curved inner tube wall 102Ci is formed at the point where the straight-line is used. The shortest distance is on the approximately straight (planar) wall 102cis connecting the two edges on the inner side of the curved portion, thereby forming a burn width x with a minimum burn width xa. Although the straight walls 102ci are preferably straight planes, this is not limiting and the walls 102ci may be any curved surface. In addition, the width dimension W is desirably defined as the width dimension of the plane 102ci continuously changing from the straight pipe portion 102b.

Accordingly, the bending width c and the width dimension W of the inner side of the bending portion can be obtained from the following equation [Numerical Expression 1].

[numeric expression 1]

d<c

0.5d<W<3d.

On the other hand, in the case of forming the arcuate wall 102cia for bending the inner pipe wall 102ci, the burning width w is a width wa longer than the above-mentioned minimum burning width w _min (w _min < wa), which is not desirable.

Fig. 19 is a front view of a fluorescent lamp 101B according to a twelfth embodiment of the present invention. The present embodiment has a characteristic feature such that the tip 102e of one of the adjacent straight pipe portions 102b protrudes so as to extend in the axial direction of the straight pipe portion 102b on the connecting portion, thereby forming a protrusion 102e on the curved portion 102c of the glass bulb 2 . The protruding length da of the protrusion 102e is in the range of 5.0-20 mm, and is preferably 0.2-1.2 times the length of the outer diameter of the straight pipe portion. In the case of the present embodiment, the protruding length da is approximately 10 mm.

In addition, four bent portions 102c are formed by connecting five straight tube-shaped bulbs 2b. That is, one side of the square shape of the bulb is formed by straight tube parts 102b' and 102b' having a length half (1/2) the length of the other side, and electrodes (not shown) are sealed to the straight tube parts 102b' and 102b' on the end 102d. The base 6 is provided so as to straddle the end portions 102d of the straight pipe portions 102b' and 102b'.

In the present embodiment, since the curved portion 102c can be formed as the tip 102e and no special processing such as molding is necessary, after connecting the straight bulb portions, even in the case of connecting a plurality of straight tube portions 102b to form the bulb 102, it is easy. The bulb 102 is easily formed.

Furthermore, in the fluorescent lamp 101c shown in FIG. 20, the protrusion 102e is not formed, but then five straight pipe portions 102b are connected and molded into a square shape. The fluorescent lamp according to this embodiment is a fluorescent lamp having a small diameter, and the bulb outer tube diameter thereof is 12-20 mm, as in the twelfth embodiment. In this way, the connection of the bulb tips to each other or the connection of the bulb tips to the side surfaces can be performed with higher mechanical strength than the connection of the channel tube side to the small-diameter connection tube.

Fig. 21 is a front view of a fluorescent lamp 101F according to a first modification of the eleventh embodiment shown in Fig. 16 . This fluorescent lamp 101F has characteristic features such that one side of the outer end portion (the right side in FIG. 21 ) extends to a horizontal extension on the outer surface (lower surface) in the drawing of the electrode end portion by a length La, wherein in the One electrode 105 of a square glass bulb 101F is sealed on the outer end and the other electrode 105 is sealed on the electrode end. This modified example has substantially the same structure as the fluorescent lamp of the eleventh embodiment except for the above structure.

Accordingly, with this fluorescent lamp 101F, the length of the discharge path can be extended by the amount of the extension La on the end of the glass bulb 102, so that the dark portion between the ends of the electrode seal can be removed or reduced. Therefore, the visual appearance and overall luminous flux of the fluorescent lamp 101F can be improved.

Fig. 22(a) is a front view showing a fluorescent lamp 101G according to a fourteenth embodiment of the present invention. This embodiment has a seamless square glass bulb 12 formed in a generally box shape. The glass bulb 112 has a protective layer and a phosphor film formed on its inner surface. Inert gas and mercury are sealed therein, and a pair of electrodes 115, 115 is sealed on both end portions in the axial direction by a wire sealing or clip sealing process, thereby forming a pair of electrode sealing end portions 115a, 115a. The pair of electrode sealing ends 115a, 115a are bent in parallel or perpendicularly to the single curved face of the glass bulb 112 from its base as shown in FIG. The following manners are arranged horizontally together, as shown in FIG. 22, so that the portions other than the pair of motor sealing portions 115a and 115a form a substantially closed box shape. A base 116 having a cylindrical shape similar to a box is provided on the outer surfaces of the pair of motor sealing parts 115a, 115a so as to straddle the electrode sealing end parts 115a, 115a. The lamp base 116 has a power supply part 116b constituted by, for example, four pins 116a electrically connected to the paired electrodes 115 and 115 .

According to the fluorescent lamp 101G, the glass bulb 112 has a ring structure substantially closed in a box shape on the light emitting portion except for the pair of motor sealing end portions 115a and 115a forming the dark portion, so that a basic box can be realized without showing the dark portion Shape or ring light emission, thereby enhancing the visual appearance.

In addition, since the base 116 protrudes inside the square glass bulb 112 and does not protrude outward, damage to the electrode sealing end portions 115a and 115a can be prevented or reduced during packaging and transportation of the fluorescent lamp 101G, and in addition, the glass bulb 112 can be effectively utilized. external space.

Furthermore, as shown in FIG. 22(b), in this embodiment, although the electrode 115 is attached to the flared stem 115b in the fluorescent lamp 101G, the flared stem 115b may be replaced with a button stem. According to this modification, the button stem is set lower in height than the flared stem, so that the length 1b of the electrode sealing end portion 115a can be reduced by a length corresponding to this length in order to reduce dark portions.

23(a)-(e) are front views of fluorescent lamps 101H, 101I, 101J, 101K, and 101L, respectively, according to first to fifth modifications of the fourteenth embodiment of the present invention. A fluorescent lamp 101H according to the first modification shown in FIG. 23(a) is characterized in that a curved portion 112c1 is formed in an arc whose radius of curvature is larger than that of the curved portion 112c of the fluorescent lamp 101G shown in FIG. 22(a), and The structure other than this feature is the same as that of the fluorescent lamp 101G of the fourteenth embodiment described above. In the following second to fifth modification examples, the same structure or composition as that of the fourth embodiment will be employed except for the parts described with reference to FIGS. 23(b)-(e).

The fluorescent lamp 101I according to the second modification shown in FIG. 23(b) is characterized in that the curved portion 112c2 is formed to a larger width than the curved width wc of the curved portion 112c of the fluorescent lamp 101G shown in FIG. 22(a). According to this feature, since the bent portion 112c2 has the large bent width wc as described above, the coldest portion can be formed on the bent portion 112c2.

A fluorescent lamp 101J according to a third modification example shown in FIG. According to this feature, since the pair of electrode sealing end portions 115a and 115a do not protrude inside the square glass bulb 112, the square inner space can be effectively utilized.

A fluorescent lamp 101K according to a fourth modified example shown in FIGS. 23( d) and ( e ) is characterized in that the pair of electrode sealing end portions 115 a and 115 a are bent so as to face the backside surface of FIGS. 23 and ( d ) and its front side. The surface protrudes. According to the present fluorescent lamp 101L, the electrode sealing end portion does not protrude inside or outside the square glass bulb 112, and the square inner space and the outer space of the square glass bulb 112 can be effectively used.

Fig. 24 is a schematic plan view showing a lighting fixture or device according to a fifteenth embodiment of the present invention. The lighting fixture has a flat plate-shaped holder (device) main body 110 and is arranged such that fluorescent lamps 101x, 101y, and 101z are combined into this holder main body 110 in a concentric manner. As such fluorescent lamps 101x-101z, any one of the fluorescent lamps 101A-101L according to the eleventh to fourteenth embodiments or a combination thereof can be used without problems.

The holder main body 110 is provided with an inverter (not shown) as a lighting device to deliver high-frequency lamp power, 10 KHz or above, to the fluorescent lamps 101x-101y and 101z, thereby realizing high-frequency lighting.

Fluorescent lamp 101x is equivalent to a conventional 30W annular fluorescent lamp. The overall length 1 of the glass bulb 102 is 225mm, the maximum inner width is 192mm, the outer diameter is 16mm, and the wall thickness of the glass bulb 102 is 1.0mm. The fluorescent lamp 101x has a rated lamp power of 20W, and the lamp is lit with a high output characteristic lamp power of 27W.

The fluorescent lamp 101y is equivalent to a conventional 32W circular fluorescent lamp. The overall length 1 of the glass bulb 102 is 299mm, the maximum inner width is 267mm, the outer diameter is 16mm, and the wall thickness of the glass bulb 102 is 1.0mm. The fluorescent lamp 101y has a rated lamp power of 27W, and the lamp is lit with a high output characteristic lamp power of 38W.

Fluorescent lamp 101z is equivalent to a conventional 40W annular fluorescent lamp. The overall length l of the glass bulb 102 is 373mm, the maximum inner width is 341mm, the outer diameter is 16mm, and the wall thickness of the glass bulb 102 is 1.0mm. The fluorescent lamp 101y has a rated lamp power of 34W, and the lamp is lit with a high output characteristic lamp power of 48W.

25-27 show a sixteenth embodiment of a fluorescent lamp according to the present invention, wherein FIG. 25 is a front view of a lamp with wires in a state where the lamp cap is removed, FIG. 26 is an enlarged sectional view of a tube end, and FIG. Schematic diagram explaining the steps for forming a discharge vessel.

In these figures, a fluorescent lamp FL is provided with a discharge vessel DV and a base B. As shown in FIG. The discharge vessel DV is approximately rectangular in its overall structure and has a curved discharge path therein. In addition, the discharge vessel DV includes a glass bulb 202 , a protective layer 203 , a fluorescent layer 204 and a pair of electrodes 205 and 205 . The discharge vessel also includes a discharge medium containing amalgam 202g and 202g sealed therein.

The glass bulb 202 is formed by locally heating and melting and bending a straight cylindrical glass tube so as to provide a generally rectangular shape as a whole. Three straight pipe portions 202b and two short straight pipe portions 202b forming four sides of a square shape, and four curved portions 202c forming corner portions and a pair of end portions 202d are connected and arranged on the same plane. The pair of tube ends 202d and 202d includes a pair of thin tubes 202f and 202f.

Three straight pipe portions 202b constitute three adjacent sides of the rectangular shape, and two short straight pipe portions 202b extend in directions opposite to each other so as to constitute the remaining sides. The curved portion 202c connects adjacent pairs of straight pipe portions 202b at right angles. The pair of end portions 202d and 202d are formed by the free ends of a pair of straight tube portions 202b and 202b and are sealed by sealing the flared stem S of each electrode holder M to the end of the glass bulb before bending the glass tube.

The electrode holder M is an assembly consisting of the initially assembled horn stem H, thin tube 202f, electrode 205, and lead wire 202j, and a pair of such assemblies are sealed in a glass tube by melting the flared portion of the horn stem H onto the end 202d of the glass tube. Then, the glass bulb 202 is sealed, and as described later, the thin tube 202f is connected to the glass bulb 202, the electrode 202 is sealed, and the lead wire 202j is protruded from the electrode 205. As shown in FIG. 26, both end portions 202d of the glass bulb 202 are molded when sealing the flared stem H, thereby forming the narrow portion 202k.

A pair of thin tubes 202f extend outward from a pair of end portions 202d of the glass bulb 202 . The inner end of the thin tube 202f communicates with the exhaust hole in the glass bulb 202 . On the other hand, the outer end of the thin tube 202f is sealed, and the inner surface thereof protrudes inward, as shown in FIG. 26 . In addition, the pair of thin tubes 202f are bent at their front ends so as to provide substantially right angles parallel to each other and extend in a direction substantially perpendicular to the tube axis. In addition, the paired thin tubes 202f extend in an elongated shape before the tips 202f2 are sealed.

Next, a method of manufacturing the fluorescent lamp F1 according to the present embodiment will be described with reference to FIG. 27 .

This manufacturing method is substantially the same as the manufacturing method described with reference to FIG. 2, therefore, only a few aspects different from the method shown in FIG. 2 will be described in detail below.

First, as shown in FIG. 27(a), heat and soften the first bent portion-form a predetermined portion with a gas burner B, and as shown in FIG. The angle between them is 90 degrees, and then the first curved portion 202c is formed into a predetermined shape by steps such as molding. Next, the gas burner B is also used to heat and soften the bent portion adjacent to the first bent portion 202c-forming a predetermined portion, and performing bending and molding steps, thereby forming the second bent portion 202c, as shown in FIG. 27(c) shown. Likewise, the gas burner B is used to sequentially heat and soften the bent portion-forming a predetermined portion and performing bending and molding steps, as shown in Figure 27(d) and (e), thereby forming a rectangular discharge vessel DV, as shown in Figure 27(d) and (e). 25, it forms four curved portions 202c. In addition, the middle portions of the paired thin tubes 202f and 202f are bent downward approximately at right angles in the drawing so that their tips extend in parallel in an elongated shape. The thin tube 202f is shortened during sealing after sealing the discharge medium.

In the venting/sealing process, the discharge medium is sealed after the interior of the discharge vessel DV is vented. The pair of thin tubes 202f and 202f protruding from a pair of end portions 202d of the discharge vessel DV are connected to an exhaust device (not shown), and the discharge vessel DV is drawn out from both end sides 202d at the same time. Thus, venting can be reliably performed even in a case where the discharge vessel has a polygonal shape. After this venting step, inert gas and amalgam 202g are sealed into the discharge vessel DV by means of one of the thin tubes 202f. Next, the middle portion of the pair of thin tubes 202f is heated and melted so as to close the tip of the portion held on the side of the discharge vessel DV, thereby performing a sealing step. The inner surface of the tip portion 202f2 of the narrow tube 202f sealed in this way protrudes inward.

Other embodiments of the fluorescent lamp LF according to the present invention will be further described below with reference to FIGS. 28-32. Note that in the drawings, the same or similar reference numerals denote corresponding parts or components shown in Figs. 25-27, and descriptions thereof are omitted.

Fig. 28 shows a seventeenth embodiment of the present invention, wherein Fig. 28(a) is a schematic diagram of a partially cutaway discharge vessel before the exhaust step, and Fig. 28(b) is a side view thereof. This embodiment is different in that the middle portion of the thin tube 208 f of this embodiment is bent at a right angle to the plane including the polygonal portion of the glass bulb 202 . This configuration is advantageous for venting/sealing.

Fig. 29(a) shows an eighteenth embodiment of the present invention and is a front view of the lamp with wires in a state where the cap is removed.

That is, the glass bulb 202 is formed of three bent portions 202c and a pair of narrow tubes 202f. The free end sides of the straight pipe portion 202b are disposed close to each other at substantially right angles on both ends thereof.

As shown in FIG. 29(a), a thin tube 202f protruding from an end portion 202d of a straight tube portion 202b extending perpendicularly to a glass bulb 202 is straight with respect to the tube axis. On the other hand, the thin tube 202f protruding from the end portion 202d of the straight tube portion 202b extending parallel in the drawing of the glass bulb 202 is bent at a substantially right angle at its middle portion so as to be substantially parallel to the thin tube 202f.

Fig. 29(b) is a front view of a lamp with wires according to a nineteenth embodiment of the present invention. In this embodiment, by contrast, the structure of the pair of narrow tubes 202f is different from that of the lamp according to the glass bulb 202 of the embodiment shown in FIG. 29(s).

That is, the pair of thin tubes 202f are both gently bent at the middle portion so that their front ends generally extend in parallel toward the outside along the diagonals of the square shape.

30-32 show a twentieth embodiment of the present invention, which is characterized in that a pair of narrow tubes 201g and 201h have shapes modified from the narrow tubes 202f and 202f shown in FIG. 28(b). Except for this shape or structure, the other structures are the same as the pair of thin tubes 202f and 202f.

That is, the inner ends of the paired narrow tubes 201g and 201h communicate with the inside of the glass bulb 202, and these tubes extend in the axial direction thereof, like the thin tubes 202f and 202f shown in FIG. A pair of end portions 202d and 202d of the glass tube 202 extend outward.

As shown in FIGS. 30 and 31, wherein FIG. 31 is a plan view of FIG. 30, the middle portions of the outer end portions 201g2 and 201g2 of a pair of narrow tubes 201g and 201b are bent in an arc so as to extend vertically, and the bent portions 201g2a and 201h2a thereof are in the The directions penetrating the drawing sheet in FIG. 30 (in the diameter direction of the exhaust pipes 201g and 201h) intersect with a predetermined gap therebetween.

That is, as shown in FIGS. 30 and 31, the outer end portions 201g2 and 201h2 of a pair of narrow tubes 201g and 201h are formed to have the same shape and the same size, and are directed toward the other side in a parallel direction along the central axis O of the end portion 202d. Horizontal portions 201g2 and 201h2 extending from the end portion 1d of the side (opposite side), standing portions 201g2c and 201h2c standing vertically from the bent portions 201g2a and 201h2a are integrally formed continuously from one of the pair of end portions 202d and 202d of the glass bulb 202 .

That is, as shown in FIG. 31, the horizontal portions 201g2b and 201h2b of the thin tube outer ends 201g2 and 201h2 extend along the central axis thereof toward the mutually opposite ends 202d and 202d of the glass bulb 202, and in order to avoid collision of these two portions , the tip portion of which is formed to continue arcuately in the straight direction (vertical direction) into the straight tube-shaped upright portions 201g2c and 201h2c, and has the inside of the rectangular structure facing the glass bulb 202 at a point just before the center point C and A predetermined inclination angle (exhaust pipe protrusion angle) of the front-rear direction of the outer side at which the front ends contact each other.

At this time, the gap l between the pair of end portions 202d and 202d of the glass bulb 202 is formed to be, for example, 30mm, the curvature radius R of the bent portions 201g2a and 201h2a is 20mm, and the exhaust pipe protrusion angles will be formed at 45 degrees in mutually opposing directions. , as shown in Figure 32. In addition, the radius of curvature R may preferably be within 15 mm to 30 mm.

In addition, reference numerals 201g3 and 201h3 in FIGS. 30 and 31 denote external fitting and fixing to the upright portions 201g2c and 201h2c of the paired thin tubes 201g and 201b. In the exhaust step, the open front end of the vacuum pump head of an exhaust device (not shown) is externally fitted in an airtight manner to the outer surfaces of the ring rubbers 201g3 and 201h3, thereby exhausting the inside of the glass bulb 201, and After this degassing step, the glass bulb 201 is supplied with a discharge medium and sealed therein. After the degassing and sealing steps, the degassing outer end portions 201g2 and 201h2 are pinched off by a predetermined length so as to be stored in the base B and covered. For example, four power receiving pins 207 are arranged upright on the outer circumference of the lamp base B, and the power receiving pins 7 are electrically connected on their inner ends to the four lead wires 201g, respectively.

According to this fluorescent lamp FL, although the glass bulb 202 is exhausted almost simultaneously from both ends thereof through the pair of narrow tubes 201g and 201h, it is possible to seal discharge from both ends of the glass bulb 202 through the pair of narrow tubes 201g and 201h almost simultaneously. medium. Thus, even in the case where the glass bulb 202 is long and polygonal, exhaust can be well performed, thereby significantly reducing residual impurity gases in the discharge vessel. Therefore, the luminous flux maintenance factor of the fluorescent lamp can be significantly improved.

In addition, since the curvature radius of the curved portions 201g2a and 201h2a of the pair of narrow tubes 201g and 201h is 15 to 30mm, mercury inserted from the narrow tubes 201g and 201h passes through the upright portions 201g2c and 201h2c of the narrow tubes 201g and 201h by its own weight. And the horizontal parts 201g2b and 201h2b move smoothly, thus being inserted into the glass bulb 202.

In this way, mercury can be quickly and reliably inserted into the glass bulb 202, and sealing efficiency can be improved.

In addition, when the radius of curvature of the curved portions 201g2a and 201h2a of the pair of thin tube outer ends 201g2 and 201h2 is less than 15mm, the vertical angle of the bent portions 201g2a and 201h2a becomes an acute angle close to a right angle, making it difficult to insert mercury into the thin tube in the outer end.

On the other hand, when the radius of curvature of the curved portions 201g2a and 201h2a of the pair of thin tube outer end portions 201g2 and 201h2 exceeds 30mm, the vertical angles of the curved portions 201g2a and 201h2a become obtuse angles. Thus, the amount of expansion by which the upstanding portions 201g2c and 201h2c of the thin tubes 201g and 201h expand toward the sealed end side 201d of the glass bulb 201 increases, resulting in a large gap between the pair of sealed end portions 202d and 202d, causing a decrease in lamp efficiency. question.

According to the present embodiment, since the curved portions 201g2a and 201h2a of the thin tubes 201g and 201h have a radius of curvature of 15-30 mm, the above-mentioned problem can be eliminated in advance.

In addition, since the horizontal portions 201g2b and 201h2b of the pair of outer end portions 201g2 and 201h2 of the thin tubes 201g and 201h are inclined so that their central axes deviate from each other, the horizontal portions 201g2b and 201g2b of the pair of outer end portions 201h2 of the thin tubes 201g and 201h 201h2b may extend near the sealing end portions 201d and 201h without causing the horizontal portions 201g2b and 201h2b to contact (collide) with each other.

Accordingly, the horizontal portions 201g2b and 201h2b of the pair of thin tubes 201g and 201h can be longer without increasing the gap between the pair of sealed end portions 202d and 202d of the glass bulb 202, thereby making it easier to make the bent portions 201g2a and 201h2a The radius of curvature is larger without increasing the dark part.

In addition, since the glass bulb 202 is formed in a rectangular annular shape, and a pair of sealing end portions 202d and 202d as annular axial end portions are disposed facing each other with a predetermined gap 1 therebetween, even when the glass bulb 202 has a long axial In the case of the length, the pair of thin tubes 201g and 201h on the pair of sealed end portions 202d and 202d are arranged at positions close to each other, so that the exhaust gas treatment can be performed more easily through the thin tubes 201g and 201h. Moreover, the exhaust of the glass bulb 202 can be performed simultaneously through the pair of thin tubes 201g and 201h located on the two sealed end portions 202d and 202d of the glass bulb 202, thereby reliably even in the case of a polygonal glass bulb 202 such as a rectangle. Exhaust. Thus, the luminous flux maintenance factor of the obtained fluorescent lamp FL can be improved.

It should also be noted that the above embodiments have been presented above with reference to the case where the glass bulb is formed in a rectangular shape, but the invention is not limited to this shape, but can also be applied to any other shape, such as a rectangular, round or double ring bulb wait. The outer diameter and axial length of the glass bulb are also not limited to those dimensions described with reference to the above embodiments.

Industrial Applicability

As described above, according to the above-mentioned fluorescent lamp of the present invention, thermal degradation of the fluorescent layer formed in the straight tube portion can be reduced and decrease in initial luminous flux can be suppressed, and light can be emitted with high efficiency.

Furthermore, there is provided a fluorescent lamp which is thin due to a small tube diameter, emits light with high efficiency and has improved light output characteristics, and has an excellent luminous flux maintenance factor.

Claims (18)

1. A fluorescent lamp, comprising: Bulb formed by heating a bent portion of a straight tube-shaped bulb member with an outer tube diameter of 12-20mm and a tube length of 800-2500mm-forming a predetermined portion so as to provide a plurality of bent portions and the same with the bent portion by bending processing Adjacent straight pipe portions, such that the straight pipe portions pass through the curved portion are disposed substantially in the same plane; electrodes sealed therein are formed adjacent to the pair of end portions so as to form a discharge path through the straight pipe portion and the curved portion; forming a phosphor layer on the inner surface of the bulb; and sealing the discharge medium including mercury; and A lamp cap provided at the end of the bulb. 2. The fluorescent lamp according to claim 1, wherein the bent portion-forming predetermined portion is bent so that the radius of curvature on the inner surface of the bent portion is in the range of 1 to 3 times the inner diameter of the tube, and the fluorescent lamp bonded to the bent portion The amount (mg/cm ² ) of the layer is 1/2 or more of the amount of the fluorescent layer in the straight pipe portion. 3. The fluorescent lamp according to claim 1, wherein the applied amount of the phosphor particles constituting the phosphor layer of the straight tube portion is 4.0-7.5 mg/cm ² . 4. The fluorescent lamp according to claim 1, wherein a protective layer having a thickness of 0.5 [mu]m or more is formed on the inner surface of the bulb, and the fluorescent layer is formed on the protective layer. 5. The fluorescent lamp according to claim 1, wherein a length of the bent portion-forming predetermined portion is in the range of 5-50% of the total length of the straight tube shaped bulb. 6. The fluorescent lamp according to claim 1, wherein the bulb is formed into a substantially rectangular shape by five straight tube portions, and bent portions are formed at diagonal positions of the rectangle, and the bulb is provided at a substantially central portion of one side of the rectangle. on both ends. 7. The fluorescent lamp according to claim 1, wherein the base is provided with a rotation limiting member for limiting a rotation angle of the base relative to the end of the bulb to an angle smaller than a predetermined angle. 8. The fluorescent lamp according to claim 1, wherein the rotation restricting member is formed by forming a base and an end of the bulb, wherein the base is fitted on the end of the bulb so as to provide an axial cross-sectional shape of an oval shape. 9. The fluorescent lamp according to claim 1, wherein the rotation restricting member is an engaging member formed on at least one of two connecting portions of the cap and the end of the bulb to which the cap is fitted, and adapted to restrict the rotation of the cap beyond a predetermined angle by engaging the cap . 10. A fluorescent lamp, comprising: A bulb formed by: connecting a plurality of straight pipe parts with an outer pipe diameter of 12-20mm in the same plane through a curved part; forming a pair of close ends in which electrodes are sealed so as to pass through the straight pipe parts and the curved parts partially forming a discharge path; forming a fluorescent layer on the inner surface of the bulb; and sealing the discharge medium including mercury; and a lamp cap arranged on the end of the bulb; Wherein the coldest portion maximizing cooling is formed on at least one of the curved portions when lit. 11. The fluorescent lamp according to claim 10, wherein the maximum length of the inner pipe diameter on the bent portion is 1.2 times or more than the inner pipe diameter of the straight pipe portion. 12. The fluorescent lamp according to claim 10, wherein at the bent portion, one tip of the adjacent straight pipe portion extends in the axial direction of the straight pipe portion so as to protrude beyond the connecting portion. 13. A fluorescent lamp, comprising: Discharge vessel having a glass bulb formed by partially bending a glass tube having an outer tube diameter of 12-20 mm and a tube length of 800-3000 mm so as to form a plurality of straight tube parts arranged alternately adjacently in the same plane and The curved portion so that both ends provide straight pipe portions adjacent to each other so as to provide a polygonal shape as a whole, the glass bulb is provided with a pair of sealed thin tubes protruding from both ends of the glass bulb for exhaust, forming a fluorescent layer on the inner surface side of the glass bulb, a pair of electrodes sealed on the inside of both ends of the glass bulb, and a discharge medium sealed inside the glass bulb; and Lamp caps arranged at both ends of the bulb. 14. A fluorescent lamp according to claim 13, wherein a part of at least one of the pair of narrow tubes is bent so that the pair of narrow tubes extend substantially parallel to each other. 15. The fluorescent lamp according to claim 13, wherein the central axes of the horizontal portions of the pair of thin tubes extending in the horizontal direction on sides of the ends of the bulb facing each other are arranged to deviate from each other. 16. A lighting device, comprising: lighting equipment main unit; A fluorescent lamp according to claim 1, 10 or 13 arranged in a lighting device main unit; and A high-frequency ignition circuit that ignites a fluorescent lamp by applying a high-frequency voltage of 10KHz or higher to it. 17. A method of manufacturing a fluorescent lamp, comprising the steps of: Form a discharge vessel with a straight tube shaped glass bulb, wherein the fluorescent layer is provided on the inner surface of a glass tube with an outer tube diameter of 12-20 mm and a tube length of 800-3000 mm, sealed at the end of the glass tube for supporting electrodes and having A pair of capillary electrode holders; A shaped discharge vessel in which a straight tube shaped glass bulb is partially heated to soften and then bent so that a plurality of tube sections adjacent to each other and bent sections are alternately formed in the same plane so that the two ends constitute a straight tube section and adjacent to each other so as to provide an overall polygonal shape; After the step of forming the discharge vessel, venting the interior of the discharge vessel from a pair of thin tubes protruding from the ends of the glass bulb, followed by sealing the discharge medium and sealing the narrow tubes; and Lamp caps are provided at both ends of the discharge vessel. 18. The manufacturing method according to claim 17, wherein the pair of narrow tubes extend in the horizontal direction on sides of the ends of the bulb opposite to each other and have curved portions having a radius of curvature of 15-30 mm.

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