JP2001283628A - Discharge lamp device - Google Patents

Abstract

(57) Abstract: In a discharge lamp device in which a gap between a holder cap and a discharge lamp is filled with an adhesive, the discharge lamp does not fall out of the holder cap, and the discharge lamp and the holder cap are combined. To provide a highly reliable discharge lamp device. SOLUTION: The discharge lamp device includes a straight tubular discharge lamp and a holder cap for receiving an end of the discharge lamp, and a gap is filled between the holder cap and the discharge lamp with an adhesive. The cap has a tubular portion having an opening formed in the front and an inner periphery formed along the tube axis of the discharge lamp, and an adhesive around the inner surface of the tubular portion of the holder cap, An engaging portion to be engaged is formed so as to be convex or concave, and the positional relationship with the adhesive is defined by the engaging portion, and the engaging portion is mounted on the discharge lamp.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp device and, more particularly, to a light source device for illuminating a document which is applied to office automation equipment such as a facsimile, an image scanner and a copying machine.

[0002]

2. Description of the Related Art Generally, a discharge lamp device as shown in FIG. 7 is used as a light source for illuminating a document. In FIG. 1, for example, a rare gas fluorescent lamp is used as the discharge lamp 1. According to this, a rising characteristic after lighting is good and a large light output can be obtained in the aperture section, which is particularly preferable. In such a discharge lamp 1, a discharge vessel 11 is formed of a long glass tube, and a pair of electrodes 12 is disposed on the outer surface thereof in a longitudinal direction so as to face each other, and a slit-shaped aperture portion is formed on an inner surface of the discharge vessel 11. Is formed, and a mixed gas of a rare gas containing xenon as a main component is sealed. A power supply terminal 14 is joined to each of the electrodes 12 at one end of the discharge vessel 11, and is drawn out from an outlet (not shown) of a holder cap attached to an end of the discharge lamp 1. An adhesive 3 is injected into the inside of the holder cap 2 so as to fill a gap with the discharge lamp 1. Reference numeral 21 in the drawing denotes a mounting ear portion formed integrally with the holder cap 2, and is used, for example, when this discharge lamp device is attached to a document illumination device.

[0003] The above-described discharge lamp device has a document illuminating device (not shown) such that the light emitted from the aperture section 16 has a predetermined incident angle with respect to the document surface (that is, the surface to be irradiated) as shown in FIG. ). At present, theoretical considerations have been made regarding the aperture opening angle of the fluorescent lamp and the illuminance of the document surface when used as a reading light source. (Reference 1: Kanzaki, Komiya, Journal of the Institute of Image Electronics Engineers of Japan
Vol. 2, No. 1976)

The holder cap 2 of the discharge lamp device is
For example, as shown in FIG.
As the material, resin or ceramics having excellent insulation and heat resistance is used. In the figure, the cylindrical portion 22 of the holder cap 2 is formed by a side surface portion 221 having a U-shaped cross section and a bottom surface portion 222 having a flat surface, for example. It is formed to extend on the same plane as the bottom part 222. A rear portion 23 is formed behind the cylindrical portion 22, and an injection hole 24 for an adhesive is formed in a central portion thereof.

In the discharge lamp device shown in FIG. 7, the end portion of the discharge lamp 1 is provided with a gap in the holder cap 2 so as not to come into contact with the back surface of the holder cap 2 as shown in a sectional view. The gap is filled with an adhesive containing polyamide resin or silicon. After the adhesive is cured, the positional relationship between the holder cap 2 and the discharge lamp 1 is determined, so that the aperture 16 is defined with respect to the holder cap 2.

Accordingly, when the discharge lamp device is attached to the document irradiating device by utilizing a part of the holder cap, the discharge lamp positioned with the holder cap is positioned in the document irradiating device, and therefore, the aperture portion and the document are illuminated. The positional relationship with the plane is also determined.

[0007]

However, in the above-described discharge lamp device, if the temperature around the discharge lamp device is too low, the adhesive filled in the holder cap undergoes heat shrinkage, resulting in a minute gap between the inner surface of the holder cap and the adhesive. When such a gap is formed, the adhesion between the holder cap and the adhesive may be impaired and the discharge lamp may come off from the holder cap.

In view of the above, it is an object of the present invention to provide a discharge lamp device in which a gap between a holder cap and a discharge lamp is filled with an adhesive so that the discharge lamp does not fall out of the holder cap. Another object of the present invention is to provide a highly reliable discharge lamp device at a joint between a discharge lamp and a holder cap.

[0009]

SUMMARY OF THE INVENTION The present invention comprises a straight tube discharge lamp and a holder cap for receiving an end of the discharge lamp, and a gap is filled between the holder cap and the discharge lamp with an adhesive. In the discharge lamp device, the holder cap has a tubular portion having an opening formed in the front and an inner periphery formed along the tube axis of the discharge lamp, and an inner surface of the tubular portion. A locking portion that engages with the surrounding adhesive is formed so as to be protruded or recessed, and the positional relationship with the adhesive is defined by the locking portion. Characterized by being worn

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A discharge lamp device according to the present invention is shown in FIGS.
This will be described with reference to FIG. The same parts as those of the conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted. FIG.
FIG. 2 is an example of a discharge lamp device according to the present invention, which is an enlarged cross-sectional view illustrating a portion where a holder cap is attached to an end of the discharge lamp, and FIG. 2 is a cross-sectional view taken along a broken line AA ′.
1 and 2, a rare gas fluorescent lamp having an aperture formed therein is preferably used as the discharge lamp 1 as in the conventional discharge lamp device. Here, the detailed description is omitted.

The holder cap 2 is preferably made of a resin having excellent insulation and heat resistance. For example, polycarbonate (P)
C) and polybutylene terephthalate (PBT) are preferred. Ceramics other than resin can also be used.

Further, the configuration of the holder cap 2 will be described with reference to FIG. FIG. 2 is a perspective view of the holder cap 2 in this embodiment. The holder cap 2 has an opening at the front, a cylindrical portion 22 formed substantially along the side surface of the discharge lamp, and a rear portion 23 formed with an adhesive injection hole 24 at the rear thereof. Have been. Also, mounting ears 2
Reference numeral 1 denotes a screw whose bottom surface is on the same plane as the bottom surface of the bottom surface portion 222 and is formed to extend from the bottom surface portion 222, and is used when attached to a device to be incorporated such as a document illumination device. A hole 211 is provided. The cylindrical part 22
Is a side part 2 whose inside is molded to such an extent that it can be accommodated with a gap between the discharge lamp and a U-shaped cross section.
21 and a bottom surface portion 222 formed of a flat surface.
The cylindrical portion 22 has a bottom portion 2 at a middle portion in the longitudinal direction.
An engagement portion 25 is provided on the inner surface of the projection 22.

With reference to FIGS. 1 and 2 described above, a state in which the discharge lamp 1 is inserted into the holder cap 2 and filled with an adhesive will be described. In FIGS.
And the surrounding adhesive 3 are engaged with each other.
Is locked to the holder cap 2, and
It cannot move in any of the directions of rotation.
Even if the adhesive 3 thermally shrinks and the adhesiveness with the holder cap 2 is reduced, and a gap is formed between the two, the gap is on the order of microns and very small.
The state of engagement between the locking portion 25 and the adhesive 3 is maintained without being damaged, and the positional relationship between the discharge lamp 1 and the holder cap 2 is not lost.

As described above, the adhesive 3
Are locked and positioned with respect to the holder cap 2, so that the positional relationship between the discharge lamp 1 and the holder cap 2 does not collapse.

Therefore, even if the discharge lamp device having the above-mentioned configuration is fixed to various irradiation devices such as a document irradiation device using a holder cap, the positional relationship between the discharge lamp 1 and the holder cap 2 determined at the beginning is maintained. Therefore, for example, problems such as the discharge lamp 1 rotating and the aperture portion being displaced with respect to the document surface, and the discharge lamp 1 falling out of the holder cap 2 do not occur.

Next, an embodiment of the second invention of the present application will be described. FIG. 4 is a perspective view of the holder cap 2 according to the second invention, as viewed from behind. In the figure, a locking portion 26 is provided on a holder cap 2 with a rear portion 23.
It is formed by cutting off at opposing portions in an edge portion extending from the cylindrical portion 22 to the cylindrical portion 22. In addition, a hole 24 for injecting an adhesive is formed in the center of the rear portion 23.

An embodiment of the present invention will be described with reference to FIG. FIG. 3 is a cross-sectional view of the discharge lamp device cut along a plane parallel to the bottom surface 222 of the holder cap 2 at the position of the engagement portion 26. The same parts as those in the drawings described in the preceding paragraph are denoted by the same reference numerals, and detailed description thereof will be omitted. At the same time that the end of the discharge lamp 1 is inserted into the holder cap 2 and the adhesive 3 is injected into the holder cap 2,
The adhesive 3 flows into the locking portion 26. Therefore, after the adhesive is cured, as shown in FIG.
Is in a state in which the adhesive 3 inside the engaging portion 26 is engaged.

Since the adhesive 3 flowing into the locking portion 26 and the locking portion 26 are engaged on the wall surface as shown in FIG.
If the adhesive 3 thermally shrinks, the adhesive 3 and the holder cap 2
The initial positional relationship between the discharge lamp 1 and the holder cap does not collapse even if the adhesion between the discharge lamp 1 and the holder cap is lost.

In the second aspect of the present invention, since the discharge lamp 1 and the holder cap 2 are positioned with the adhesive 3 at the locking portion 26 of the holder cap 2, the discharge lamp 1 is positioned with respect to the holder cap 2. It cannot be moved in any of the axial direction and the rotational direction, and the positional relationship between the discharge lamp 1 and the holder cap 2 that is originally defined is maintained, so that the reliability of the joint portion is significantly improved. Also, even when the discharge lamp device according to the present invention is fixed to various lighting devices by using a part of the holder cap 2, the positional relationship between the discharge lamp 1 and the holder cap 2 that is originally specified is maintained. The discharge lamp 1 does not shift with respect to the surface to be illuminated.
Does not come off from the holder cap 2.

Incidentally, the form of the holder cap according to the present invention is not limited to the above configuration. For example, FIG. 6 is a perspective view of the holder cap according to the present invention. As shown in FIG. 6, it is also possible to provide the locking portion 27 on the inner surface of the holder cap 2 in the circumferential direction. Many may be provided. As described above, when a large number of the locking portions 27 are formed,
Since the contact area between the holder cap 2 and the adhesive increases, the reliability of the joint between the holder cap 2 and the adhesive increases, which is more preferable.

[0021]

As described above, according to the present invention, a locking portion is provided on the inner peripheral surface of the cylindrical portion of the holder cap and is positioned by engaging with the adhesive. Even if the adhesion of the holder cap is impaired or a minute gap is formed, the initial positional relationship between the adhesive and the holder cap is maintained without impairing the discharge lamp and the holder cap. Is positioned, and the reliability at the joint between the discharge lamp and the holder cap is significantly improved.

[Brief description of the drawings]

FIG. 1 is an enlarged cross-sectional view of an example of a discharge lamp device according to the present invention, in which a portion where a holder is attached to an end of a discharge lamp is enlarged.

FIG. 2 is a sectional view taken along a broken line A-A '.

FIG. 3 is a schematic view illustrating a configuration of a holder cap.

FIG. 4 is a perspective view of a holder cap according to a second invention.

FIG. 5 is a cross-sectional view of the discharge lamp device cut at a portion where an engagement groove of a holder cap is formed.

FIG. 6 is a perspective view showing another embodiment of the holder cap.

FIG. 7 is an explanatory view of a conventional discharge lamp device.

FIG. 8 is an explanatory diagram showing a positional relationship between an aperture section and a document surface.

FIG. 9 is a view showing a configuration of a holder cap according to a conventional discharge lamp device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Discharge lamp 11 Discharge container 12 Electrode 13 Phosphor layer 14 Power supply terminal 2 Holder cap 21 Mounting ear part 211 Screw hole 22 Cylindrical part 221 Side part 222 Bottom part 23 Back part 24 Injection hole 25, 26, 27 Locking part

Continued on the front page (72) Inventor Yoshihisa Yokokawa 1194 Sado, Bessho-cho, Himeji-shi, Hyogo USHIO Electric Co., Ltd.F-term (reference) AA01 BA13 CA02 CA09 XA01

Claims (1)

[Claims] 1. A discharge lamp device, comprising: a straight tubular discharge lamp; and a holder cap for receiving an end of the discharge lamp, wherein a gap is filled with an adhesive between the holder cap and the discharge lamp. The holder cap has a tubular portion having an opening formed in the front and an inner periphery formed along the tube axis of the discharge lamp, and the inner surface of the tubular portion is connected to an adhesive around the tubular portion. A discharge lamp, wherein the engagement portion is formed so as to be convex or concave, and is mounted on the discharge lamp in a state in which a positional relationship with the adhesive is defined by the engagement portion. apparatus.