JP2008041605A - LIGHTING DEVICE AND REFRIGERATOR HAVING THE SAME - Google Patents

Abstract

When a white LED based on an inexpensive GaN-based blue LED is used as interior lighting of a refrigerator or the like, white light is bluish, and the appearance of food is deteriorated and the performance is impaired. There is a problem.
By covering the entire light emitting part of a white LED 2 with a lamp cover 7 containing a yellow fluorescent material, bluish white light passes through the lamp cover 7 and dimming supplements a yellow wavelength near 560 nm. Then, natural white light without bluish light is emitted from the lamp cover 7 to enhance the effect of irradiation in the cabinet without impairing the visual impression of food.
[Selection] Figure 2

Description

  The present invention relates to an illuminating device that irradiates a stored item stored in a storage room, and a refrigerator in which the illuminating device is installed in a warehouse.

  In recent years, as a lighting device in a refrigerator, a device using a white LED has been proposed for reasons such as low heat generation, no infrared wavelength, and low voltage driving, instead of conventional incandescent lamps and light bulbs.

  As a refrigerator using a conventional white LED as an illumination device, there is a refrigerator in which a plurality of white LEDs are mounted on a single substrate and installed on the top surface of the interior to irradiate the interior (for example, Patent Document 1). reference).

  FIG. 6 shows a perspective view of a conventional refrigerator lighting device described in Patent Document 1. In FIG.

  As shown in FIG. 6, the lighting device includes a mounting substrate 1, a white LED 2, and a heat insulating plate 4, and is installed in a refrigerator.

  The mounting substrate 1 has a flat plate shape, a circuit pattern (not shown) is formed on one surface or both surfaces, and uses an epoxy resin-based substrate or an insulating metal substrate having good thermal conductivity. The white LED 2 is formed in a bullet shape, and has a structure in which white light is obtained by exciting a fluorescent material using blue light from a GaN-based blue LED, and two energization terminals 3 for energizing current are derived.

  The heat insulating plate 4 is formed in a flat plate shape using a resin such as urethane, and a plurality of insertion holes are provided in parallel to be provided between the mounting substrate 1 and the white LED 2. Here, in the white LED 2, the current-carrying terminals 3 are inserted through the insertion holes of the heat insulating plate 4, soldered to the circuit pattern of the mounting substrate 1, and a plurality of white LEDs 2 are arranged on the mounting substrate 1. When the amount of heat generated by the white LED 2 is small, the heat insulating plate 4 may be eliminated.

  The operation | movement is demonstrated below about the refrigerator using white LED comprised as mentioned above as an illuminating device.

  First, when the refrigerator door is closed, the white LED 2 is not energized and the interior is not illuminated.

When the door is opened, the electronic switch such as a mechanical switch or Hall IC determines that the door is open, a DC voltage is applied to the mounting board 1, and a forward current flows to the white LED 2 through the energizing terminal 3. White light is emitted and the interior is irradiated.
Japanese Patent Laid-Open No. 11-159953

  However, in the said conventional structure, the white light light-emitted by white LED2 irradiates the inside of a store | warehouse | chamber directly, and illuminates preservation | save things, such as a foodstuff.

  In general, the white LED 2 is an inexpensive GaN-based LED, and a blue LED having a wavelength near 470 nm is used as a base, and a method of dimming a yellow wavelength near 560 nm with a fluorescent material is adopted. However, the current situation is that the distance between the LED element and the fluorescent material is too close to perform sufficient light control, and white light is inevitably bluish. When this bluish white light is applied to food, there is a problem that impairs the rendering performance, such as making the food feel visually cold or making the appearance of the food look worse.

  Recently, there is a full-color type white LED that emits three primary colors of light to obtain white light, but it is too expensive to be put into practical use for refrigerator interior irradiation.

  The present invention solves the above-described conventional problems, and provides a refrigerator in which an inexpensive GaN-based LED is used as a white LED, and a preserved product such as food is irradiated with a bluish white light. With the goal.

  In order to solve the above-described conventional problems, the illumination device of the present invention is configured to cover the entire white LED light emitting unit with a lamp cover containing a yellow fluorescent material.

  As a result, bluish white light passes through the lamp cover, so that the yellow wavelength near 560 nm, which was not sufficiently dimmable in the white LED, is replenished. Light is emitted from the lamp cover.

  In the illumination device of the present invention, a plurality of white LEDs are electrically connected in parallel, and a voltage is applied from a DC power source so that a forward current flows through the white LEDs.

  As a result, even when one white LED is turned off due to its life or the like, the forward current supply to the other white LEDs is not stopped, and the light emission is continued.

  Furthermore, the refrigerator of this invention can soften visually the illumination effect to the store | warehouse | chamber interior store at the time of door opening by providing the said illuminating device, and can improve the impression of appearance.

  The illuminating device of the present invention can obtain white light close to nature at low cost, and can obtain a color effect close to natural even when the illumination light acts. In addition, since the illumination device can obtain an illumination effect until all of the plurality of white LEDs are completely turned off, the lifetime can be extended and high reliability can be ensured.

  In addition, the refrigerator of the present invention can irradiate a preserved product such as food in a warehouse with natural white light that does not have a bluish color, so that the appearance impression of the interior is not impaired without impairing the appearance of the food. Can be increased.

  The invention according to claim 1 includes a white LED that obtains white light by exciting a fluorescent material using blue light from a blue LED, a mounting substrate in which a plurality of the white LEDs are arranged in parallel, and a yellow fluorescent material And a lamp cover that covers the entire light emitting portion from the white LED.

  By adopting such a configuration, it is possible to realize near-natural white light that does not have a bluish color with a white LED of an inexpensive GaN-based LED, and it is possible to enhance production performance as illumination economically and advantageously. .

  According to a second aspect of the present invention, the lamp cover is made of a material containing a light diffusing material.

  By adopting such a configuration, light emitted from a directional white LED can be diffused by a lamp cover and radiated over a wide range. As a result, by applying a uniform amount of light to the irradiated article, Can be eliminated.

  According to a third aspect of the present invention, there is provided a white LED that obtains white light by exciting a fluorescent material using blue light from a blue LED, a mounting board in which a plurality of the white LEDs are arranged, and a white LED. A lamp cover that covers the entire light emitting portion, and a transparent yellow film that is uniformly attached to the LED-side back surface of the lamp cover are provided.

  By adopting such a configuration, it becomes dimming closer to the light source, it is possible to easily obtain white light that is not bluish, and the configuration of the lamp cover is less restricted to obtain white light, The degree of freedom of the lamp cover configuration can be increased.

  According to a fourth aspect of the present invention, the lamp cover is formed using a transparent material such as epoxy, acrylic, polycarbonate, polyethylene, polystyrene, or polypropylene, or a composite material including any of these as a base material. is there.

  With this configuration, the lamp cover can be molded into any shape, making it possible to mold complex shapes and designing for easy installation, and the lighting device is installed at the optimal position on the installation body. can do.

  According to a fifth aspect of the present invention, a plurality of series circuits of the white LED and a current limiting resistor are provided, and these series circuits are connected in parallel to form a parallel circuit that is blocked, and both ends of the parallel circuit are connected to a direct current. Connected to a power source.

  By adopting such a configuration, forward current supply to the series circuit of each white LED and current limiting resistor can be performed independently, and even if one white LED is turned off due to life or failure, the other white LEDs are in a light emitting state. Therefore, a long-life and highly reliable lighting device can be obtained.

  According to a sixth aspect of the present invention, a parallel circuit is formed by connecting the anode side and the cathode side of the plurality of white LEDs in parallel with each other, and a current limiting resistor is connected in series with the parallel circuit. Thus, a series circuit is configured, and both ends of the series circuit are connected to a DC power source.

  By adopting such a configuration, the forward current to the plurality of white LEDs is controlled by a single current limiting resistor, so that the circuit pattern of the mounting board is simplified, space saving is achieved, and economical. In addition, an inexpensive lighting device can be obtained.

  The invention according to claim 7 is the one in which the current limiting resistor is mounted on the mounting substrate, and this makes the connection harness from the DC power source simple, thereby reducing the number of installation work steps and reducing the cost. be able to.

  The invention according to claim 8 is a refrigerator in which the lighting device is provided on a wall surface in a storage room.

  Such a refrigerator incorporates the features of the above lighting device, so that it is possible to irradiate the storage room with white light close to natural color, and as a result, the appearance of food is not impaired, and the appearance of food is not impaired. The effect can be enhanced. In addition, the interior lighting device can be simplified in configuration, can be configured at low cost, and the lighting effect is not impaired over a long period of time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Here, the same components as those in the conventional example are denoted by the same reference numerals, and detailed description thereof is omitted. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a side cross-sectional view showing an outline of the configuration of a refrigerator provided with a lighting device according to Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view of a lighting device section taken along line AA in FIG.

  The schematic structure of the refrigerator will be described with reference to FIG.

  The refrigerator includes a refrigerator main body 21 configured of a heat insulating casing, storage chambers 22, 23, and 24 formed in the refrigerator main body 21, and doors 25, 26, and 27 provided in the storage chambers 22, 23, and 24, respectively. It has. The door 25 of the storage chamber 22 is a pivot type pivotally supported by a hinge mechanism, and the doors 26 and 27 of the remaining storage chambers 23 and 24 have a drawer type door configuration.

  A vertically long illuminating device 28 is embedded in the upper portion of the inner side wall of the storage chamber 22. In addition, the storage chamber 22 is provided with a switch 29 that is turned on and off as the door 25 is opened and closed.

  When the door 25 is opened, the lighting device 28 is turned on by the ON operation of the switch 29 to illuminate the storage chamber 22.

  Here, the cooling device and the like are not directly related to the gist of the present invention and may have a well-known configuration, and thus illustration and description thereof are omitted.

  Next, the illumination device 28 will be described with reference to FIG.

  In FIG. 1, the illuminating device 28 has a configuration mainly composed of the mounting substrate 1, the white LED 2, the energizing terminal 3, and the heat insulating plate 4 as in the conventional case.

  In addition, the mounting substrate 1 is held by the spacer 6 in the inner recess 30 of the side wall 5 of the storage chamber 22, and the lamp cover 7 is disposed at a certain distance from the light emitting part of the white LED 2 and the entire light emitting part of the white LED 2. Is attached to the inner recess 30 of the side wall 5.

  The lamp cover 30 is formed of a transparent resin such as epoxy, acrylic, polycarbonate, polyethylene, polystyrene, polypropylene, or a composite material containing one of them as a base material and containing a yellow fluorescent material. It is attached so as to be detachable from the side wall 5 by appropriate means such as a locking claw 71 having some flexibility.

  In the first embodiment, the lighting device 28 is embedded in the side wall 5 of the storage room 22 of the refrigerator. However, if a stored item such as food can be irradiated through the lamp cover 7, the lighting device 28 can be located anywhere in the storage such as the top wall. It may be buried.

  About the refrigerator comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, when the door 22 of the refrigerator is closed, the white LED 2 is not energized by the OFF operation of the switch 29, and the interior of the storage room 22 is not irradiated. When the door 22 is opened, a forward current flows through the white LED 2 and white light is emitted. Up to this point, the operation is the same as in the prior art.

  Next, the bluish white light emitted from the white LED 2 proceeds to the lamp cover 7 containing a yellow fluorescent material, and the yellow wavelength near 560 nm is sufficiently dimmed. As a result, the light transmitted through the lamp cover 7 is irradiated from the lamp cover 7 to the interior as natural white light that does not have a bluish tint.

  As described above, in the first embodiment, the yellow wavelength is dimmed by the lamp cover 7 when the bluish white light from the white LED 2 passes through the lamp cover 7 containing the yellow fluorescent material. Therefore, since the interior of the storage room 22 is irradiated with natural white light without bluishness, it is possible to produce a high-quality lighting effect without deteriorating the visual impression of stored products such as food.

  Further, the surface shape of the lamp cover 7 can be diffused by light, or the lamp cover 7 contains a light diffusing material so that light emitted from the directional white LED 2 is diffused by the lamp cover 7 and stored. The inside can be irradiated. As a result, uniform white light hits a preserved product such as food, so that visual irradiation spots can be suppressed, and lighting performance can be further improved.

  Further, the lamp cover 7 is formed into a free shape by forming the lamp cover 7 as a base material using a transparent resin such as epoxy, acrylic, polycarbonate, polyethylene, polystyrene, polypropylene, or a composite material containing one of them. The lighting device 28 can be installed at an arbitrary position in the storage chamber 22.

(Embodiment 2)
FIG. 3 is a cross-sectional view showing a state in which the lighting device is installed on the side wall of the refrigerator according to Embodiment 2 of the present invention, and is a view corresponding to FIG. Here, the same components as those in the first embodiment will be described with the same reference numerals.

  In the second embodiment, the difference from the first embodiment is that in the first embodiment, the lamp cover 7 includes a yellow fluorescent material. However, in the second embodiment, the lamp cover is used. 7a is different in that it does not contain a yellow fluorescent material.

  In FIG. 3, the illumination device 28 has a configuration mainly including the mounting substrate 1, the white LED 2, the energizing terminal 3, and the heat insulating plate 4 as in the conventional case.

  In addition, the mounting substrate 1 is held by the spacer 6 in the inner recess 30 of the side wall 5 of the storage chamber 22, and the lamp cover 7 a is placed at a certain distance from the light emitting part of the white LED 2 and the entire light emitting part of the white LED 2. Is attached to the inner recess 30 of the side wall 5. The specific mounting structure, material, and the like of the lamp cover 7a may be the same as those in the first embodiment, and thus the description thereof is omitted. Also, the mounting position of the lighting device 28 can be provided at an appropriate location where a predetermined lighting effect can be obtained, as in the first embodiment.

  Further, a light transmissive yellow film 8 is attached to the back surface of the lamp cover 7a on the white LED 2 side.

  About the refrigerator comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, when the refrigerator door 22 is closed, the white LED 2 is not energized, and the interior of the storage room 22 is not illuminated. When the door 22 is opened, a forward current flows through the white LED 2 to emit white light. Up to this point, the operation is the same as in the prior art.

  Next, the bluish white light emitted from the white LED 2 first proceeds to the light-transmitting yellow film 8 to be dimmed at a yellow wavelength near 560 nm. And it advances to the lamp cover 7a and irradiates the inside of the storage chamber 22 from the lamp cover 7a as natural white light.

  Here, if necessary, the lamp cover 7a may be made of a material containing a yellow fluorescent material as in the first embodiment. With such a configuration, in addition to dimming with the light-transmitting yellow film 8, dimming of light by the lamp cover 7a can be performed, and the certainty of whitening can be increased. In addition, the content of the yellow fluorescent material can be adjusted to optimize whitening.

  As described above, in the first embodiment, the bluish white light from the white LED 2 is easily passed through the transparent yellow film 8 and the lamp cover 7a to adjust the yellow wavelength. The light can be dimmed and white light without bluish color can be realized, and illumination with higher quality can be achieved by irradiation inside the cabinet.

  Further, it is possible to use the lamp cover 7 containing the yellow fluorescent material described in the first embodiment instead of the lamp cover 7a. With such a configuration, the lamp cover 7 alone has a bluish white light. Can be easily dimmed and white light without a bluish color can be realized, and a higher quality lighting effect can be achieved by in-chamber irradiation.

(Embodiment 3)
FIG. 4 is an electric circuit diagram when the lighting device according to Embodiment 3 of the present invention is used in a refrigerator. Here, the same components as those of the second embodiment will be described with the same reference numerals.

  In FIG. 4, one end of a first current limiting resistor 9 is connected to the anode terminal side of the white LED 2 to form a first unit 10 having a series circuit configuration. The lighting device 28 includes a plurality of first units 10. The first units 10 are connected to the cathode terminals of the white LEDs 2, and the other ends of the first current limiting resistors 9 are connected to each other. The parallel connection circuit connected to is configured.

  Further, in the parallel connection circuit, the cathode terminal side of the LED 2 is on the − (minus) side of the DC power source 11, and the other end side of the first current limiting resistor 9 is on the + (plus) side of the DC power source 11 via the switch 29. Each is connected. As the illumination device 28, an electric circuit portion excluding the DC power supply 11 and the switch 29 is mounted on the mounting substrate 1.

  About the illuminating device 28 of the refrigerator comprised as mentioned above, the electric circuit operation | movement is demonstrated below.

  When the door 25 of the storage chamber 22 is opened, the switch 29 is turned on, the DC power supply 11 is activated, and a constant voltage is supplied to each first unit 10.

  As a result, the voltage of the DC power source 11 is applied to each first unit 10, and a current flows as a forward current to each white LED 2 by the resistive load of the first current limiting resistor 9, and white light is emitted.

  Further, the luminous intensity of the white LED 2 can be changed according to the value of the forward current. Based on the characteristic of the forward voltage Vf of the white LED to be used, the voltage value of the DC power supply 11 and the resistance of the first current limiting resistor 9 The forward current may be determined by adjusting the value.

  In the third embodiment, the DC power supply 11 has been described as the constant voltage system. However, if the forward current accuracy is required, the DC power supply 11 may be the constant current system.

  As described above, in the third embodiment, the forward current supply to each white LED 2 becomes independent by connecting in parallel the first unit 10 to which the white LED 2 and the first current limiting resistor 9 are connected. Even when one white LED 2 is disconnected due to its life or failure, current supply to the other white LEDs 2 is continued. As a result, although the overall illuminance falls a little, the worst state of full extinction can be avoided, and a long-life and highly reliable lighting device can be secured.

  In addition, since the first current limiting resistor 9 is mounted on the mounting substrate 1, since it is a simple two-wire connection from the DC power source to the lighting device, wiring is also simple, and assembly is performed with simple mounting. Workability can be improved.

(Embodiment 4)
FIG. 5 is an electric circuit diagram when the illumination device according to Embodiment 4 of the present invention is used in a refrigerator. Here, the same constituent elements as those of the third embodiment will be described with the same reference numerals.

  The fourth embodiment is different from the third embodiment in that a parallel connection circuit in which cathode terminals of a plurality of white LEDs 2 are connected to each other and anode terminals are connected to each other as shown in FIG. The second unit 12 is configured by connecting one end of the second current limiting resistor 13 to the anode terminal side of the white LED 2 in the parallel connection circuit.

  In the second unit 12, the cathode terminal side of the white LED 2 is on the − (minus) side of the DC power source 11, and the other end of the second current limiting resistor 13 is on the + (plus) side of the DC power source 11 via the switch 29. Are connected to each. As the lighting device 28, an electric circuit portion excluding the DC power supply 11 is mounted on the mounting substrate 1.

  About the illuminating device of the refrigerator comprised as mentioned above, the electric circuit operation | movement is demonstrated below.

  When the door 25 of the storage chamber 22 is opened, the switch 29 is turned on, the DC power supply 11 is in an operating state, and a constant voltage is supplied to the second unit 12.

  As a result, the voltage of the DC power supply 11 is applied to the second unit 12, and the current flows as a forward current almost evenly to each white LED 2 by the resistance load of the second current limiting resistor 13, and white light is emitted. .

  Further, the luminous intensity of the white LED 2 can be changed according to the value of the forward current. Based on the characteristic of the forward voltage Vf of the white LED to be used, the voltage value of the DC power supply 11 and the resistance of the second current limiting resistor 13 are used. The forward current may be determined by adjusting the value.

  In the fourth embodiment, the DC power supply 11 is described as a constant voltage system. However, the DC power supply 11 may be a constant current system if the accuracy of the forward current is required.

  As described above, in the fourth embodiment, a plurality of white LEDs 2 are connected in parallel, and the second unit 12 having one end connected to the second current limiting resistor 13 constitutes one second. The plurality of white LEDs 2 can emit light by the current limiting resistor 13, the circuit pattern of the mounting substrate 1 is simplified, and a space-saving and inexpensive lighting device can be obtained.

  In addition, since the second current limiting resistor 13 is mounted on the mounting substrate 1, a simple two-wire connection is made from the DC power source 11 to the lighting device 28, wiring is also simple, and assembly workability is improved. .

  In the first, second, third, and fourth embodiments, the storage chamber 22 having the hinged door 25 has been described as an example. However, the storage chamber 23 having the drawer type doors 26 and 27 as necessary. , 24 can be similarly implemented.

  As described above, the lighting device according to the present invention can be applied not only to the case where white LED lighting is applied to a household or commercial refrigerator, but also to an article storage device with a door, etc. It can be applied to a wide range of equipment and equipment.

Side surface sectional drawing of the refrigerator which comprises the illuminating device in Embodiment 1 of this invention. Sectional drawing of the illuminating device part by the AA line of FIG. FIG. 2 equivalent diagram in the second embodiment of the present invention Electric circuit diagram when lighting device in Embodiment 3 of the present invention is used in a refrigerator Electric circuit diagram when lighting device in Embodiment 4 of the present invention is used in a refrigerator The perspective view of the illuminating device of the refrigerator which shows a prior art example

Explanation of symbols

1 Mounting board 2 White LED
DESCRIPTION OF SYMBOLS 3 Current supply terminal 4 Heat insulation board 5 Refrigerator side wall 6 Spacer 7 Lamp cover 7a Lamp cover 8 Transparent yellow film 9 1st current limiting resistance 10 1st unit 11 DC power supply 12 2nd unit 13 2nd current limiting resistance 21 Refrigerator body 22 Storage room 25 Door 28 Lighting device 29 Switch

Claims (8)

  A white LED that obtains white light by exciting a fluorescent material using blue light from a blue LED, a mounting substrate in which a plurality of the white LEDs are arranged in parallel, and a material containing a yellow fluorescent material, the white LED The illuminating device provided with the lamp cover which covers the whole light emission part from.   The lighting device according to claim 1, wherein the lamp cover is made of a material containing a light diffusing material.   A white LED that obtains white light by exciting a fluorescent material using blue light from the blue LED, a mounting substrate in which a plurality of the white LEDs are arranged in parallel, a lamp cover that covers the entire light emitting unit from the white LED, The illuminating device which comprises the transparent yellow film affixed uniformly on the LED side back surface of the said lamp cover.   4. The lamp cover according to claim 1, wherein the lamp cover is formed using a transparent material such as epoxy, acrylic, polycarbonate, polyethylene, polystyrene, or polypropylene, or a composite material including any of these as a base material. The lighting device according to item.   A plurality of series circuits of the white LED and a current limiting resistor are provided, and these series circuits are connected in parallel to form a parallel circuit that is formed into a block, and both ends of the parallel circuit are connected to a DC power supply. Item 5. The lighting device according to any one of Items 4 to 6.   A parallel circuit is formed by connecting the anode side and the cathode side of the plurality of white LEDs in parallel to each other, and further, a current limiting resistor is connected in series with the parallel circuit to form a series circuit, The lighting device according to claim 1, wherein both ends of the series circuit are connected to a DC power source.   The lighting device according to claim 5, wherein the current limiting resistor is mounted on the mounting substrate.   The refrigerator which equips the wall surface in a storage chamber with the illuminating device as described in any one of Claims 1-7.

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