JPH0945227A - Power supply structure of discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the commercial value of a discharge lamp from dropping because needless gas occurs from the inside of a base, and the shape of the welding zone of the base pin part widens irregularly to deteriorate the external appearance and making it hard to insert the base pin into the socket port, etc., when arc-welding the base pin of a discharge lamp. SOLUTION: For the structure, a lead bar 3, which is joined by adhesive 6 with the sealing part 2 of a discharge lamp 1 is projected from the sealing part 2, and a lead wire 4, which is connected electrically with the lead bar 3, are inserted into itself, and also the tip of the lead wire is arc-welded by a base pin. So needless gas, which occurs when arc-welding the base pin 7 of a discharge lamp, runs into the cavity 10 within the base part, and the nonconformity of the form of the welded zone 8 of the base pin part 7 vanishes, by putting this discharge clamp in power supply structure for a discharge lamp where a specified cavity 10 that the adhesive 6 does not get in is made between one end face on the base pin side of the adhesive and the opening face of the base pin part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a xenon lamp and mercury used as a light source for an ultraviolet exposure process in the manufacture of electronic devices, a light source for projection of video equipment, general lighting, a light source for printing, a light source for liquid crystal backlights, and the like. The present invention relates to a power supply structure for a discharge lamp such as a lamp.

[0002]

2. Description of the Related Art A conventional power feeding structure will be described with reference to FIG. When attaching the base to the discharge lamp, the adhesive 6 is applied to the sealing portion 2 of the discharge lamp 1 and the sealing portion 2 is inserted into the brass base 5 or the sealing portion 2 is attached. The adhesive 6 was injected after being inserted into the base 5, and the adhesive 6 was solidified and fixed.

The tip portion of the lead wire 4 joined to the lead rod 3 protruding from the sealing portion 2 of the lamp 1 and the pin portion 7 of the base 5 are mechanically and electrically connected. However, as a method of joining the base 5 and the lead wire 4, a method of melting and fixing the required amount of the silver brazing wire material by using various burners such as an oxyhydrogen burner, or placing a required amount of the brazing material at the welding location. Silver brazing such as a method of brazing by heating with the burner or an electric furnace has been used. However, this silver brazing has drawbacks in that material costs such as a brazing material and burner gas are required, and it takes time to heat the pin portion 7 of the die 5 and melt the brazing material.

Therefore, recently, as an alternative method to silver brazing, a voltage is applied between a welding electrode (not shown) and a base metal which are opposed to each other with a predetermined distance from the tip of the pin portion 7 of the base 5 to perform welding. A method has begun to be adopted in which an arc is blown in an atmosphere of a protective gas such as argon to prevent the electrode and the base from being oxidized and the heat generated at that time welds the base pin and the lead wire.

[0005]

If the base pin portion is joined by arc discharge, there are the following drawbacks. (A) By heating the base pin portion to a high temperature instantaneously, unnecessary gas is generated from the inside of the base including the lead wire,
When the unnecessary gas diffuses around the base pin portion, the molten base material and lead wire material are blown away to irregularly expand the shape of the welded portion.

(B) If the shape of the welded portion is widened, it is difficult to insert the base pin into the hole of the socket when the base pin is inserted into the socket, and the appearance is poor and the product value is lowered. . The present invention has been made to solve these disadvantages.

[0007]

In order to achieve the above object, a lead rod which is fixed to a sealing portion of a discharge lamp with an adhesive and protrudes from the sealing portion to the outside of a lamp envelope, In a power supply structure for a discharge lamp in which a lead wire electrically connected to the lead rod through a joining portion is inserted and the tip end portion of the lead wire is arc-welded at a base pin portion, the base pin of the adhesive is used. Provided is a power supply structure for a discharge lamp, which is characterized in that a predetermined gap in which the adhesive does not enter is formed between one end surface on the side and the opening surface of the base pin portion.

[0008]

As described above, by providing a predetermined gap inside the die so that the adhesive does not enter, unnecessary gas generated in the die melting portion 8 during arc welding of the die pin portion protects argon or the like during welding. It is pushed by the pressure of gas and escapes into the void inside the base. Therefore, the melted portion 8 does not scatter to the outside due to arc discharge, and the shape defect of the base pin portion does not occur.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. <Embodiment 1> FIG. 2 shows a sectional view of a power feeding structure according to a first embodiment of the present invention. A washer 10 for forming a void is passed through a lead wire 4 connected to a lead rod 3 protruding from the sealing portion 2. After applying a thermosetting inorganic adhesive 6 to the sealing portion 2, a washer is formed. The lead wire 4 is passed through the base 5 together with 10. The inner bottom surface of the base 5 is inclined, and the washer 10
Stops in the middle of this inclined surface, and a void 11 not filled with the adhesive 6 is formed inside the die 5. Alternatively, in the case of the method of injecting the adhesive 6 after passing the base 5 through the lead wire 4, the washer 10 plays a role of preventing the invasion of the adhesive, and the void 11 is formed inside the base 5. Then, the lead wire 4 is arc-welded 8 with the pin portion 7 of the base 5. <Embodiment 2> FIG. 3 shows the case where the bottom surface of the mouthpiece 5 is flat, and a washer 10 having a barb 12 on one surface is used, and the barb portion 12 is fitted with the barb pin side to insert a gap. 11 is formed, and the lead wire 4 is arc-welded to the pin portion 7 of the base 5 as in the first embodiment. <Embodiment 3> FIG. 4 uses a washer 10 having a spring 13 in place of the barb 12 on one side of Embodiment 2. <Embodiment 4> In FIGS. 5 and 6, instead of the washer 10, rings 14 and 14 'having a polygonal cross section are used. <Embodiment 5> In FIG. 7, a mouthpiece closing portion 15 and a mouthpiece body portion 16 are divided into two parts to provide a space. Further, in the above-described embodiment, the washer 10 and the rings 14 and 14 'having a polygonal cross section are not limited to metal as long as they have heat resistance, and may be various materials such as plastic, rubber, and cardboard.

[0010]

EFFECTS OF THE INVENTION The discharge lamp power supply structure of the present invention enables stable arc discharge of the base pin portion when the base is joined to the sealing portion, and the end shape of the base pin portion can be changed. A well-made finished lamp can be produced with good reproducibility.

Further, the number of manufacturing steps is greatly reduced as compared with the case where the base pin portion is conventionally processed by silver brazing.

[Brief description of drawings]

FIG. 1 shows a cross-sectional view of a conventional power supply structure for a discharge lamp.

FIG. 2 shows a cross-sectional view of a power supply structure for a discharge lamp of Example 1.

FIG. 3 shows a cross-sectional view of a power supply structure for a discharge lamp of Example 2.

FIG. 4 shows a sectional view of a power supply structure for a discharge lamp according to a third embodiment.

FIG. 5 shows a sectional view of a power supply structure for a discharge lamp of Example 4.

FIG. 6 shows a cross-sectional view of a power supply structure for a discharge lamp of Example 4.

FIG. 7 shows a cross-sectional view of a power supply structure for a discharge lamp of Example 5.

[Explanation of symbols]

 1 Discharge Lamp 2 Sealing Part 3 Lead Rod 4 Lead Wire 5 Base Part 6 Adhesive 10 Washer 11 Void

Claims (1)

[Claims] 1. A lead rod, which is fixed to a sealing portion of a discharge lamp by an adhesive, and which projects from the sealing portion to the outside of a lamp sealing body, and a lead wire electrically connected to the lead rod. Then, in a discharge lamp power supply structure in which the tip portion of the lead wire is arc-welded at the base pin portion, the adhesive between the one end surface of the adhesive on the base pin side and the opening surface of the base pin portion A power supply structure for a discharge lamp, which is characterized in that a predetermined gap that does not enter is formed.