JPH03122960A - Electrode for discharge lamp and its manufacture - Google Patents

Abstract

PURPOSE:To enhance the performance of an electrode for discharge lamp and its producibility by providing the electrode with a discharge side end part, which was turned in sufficient crystalline condition by a high temp. heat treatment, and a connection side end part whereat the non-crystalline condition is preserved by a low temp. heat treatment. CONSTITUTION:When current is fed through external terminals 14, 14, intense temp. running and incandescence take place in electrodes 1, 1 particularly in their parts at discharge side ends 1a, 1a as protrudingly contacting parts having contact resistance. The discharge side end part 1a of each electrode 1 is therefore turned in a crystalline condition suitable to arc discharge because of its being heated to sufficient temp. The connection side end part 1b mounted to a holder 12 is, on the contrary, maintained in the condition when the members were manufactured because this part does not attain the temp. to cause change in the crystalline condition due to the heat radiating effect of the holder 12, and there is not risk of losing the mechanical strength. This should enhance the performance and producibility.

Description

[Detailed description of the invention] [Field of application on Ill]

The present invention includes, for example, a mercury discharge lamp, an IJum discharge lamp,
It relates to electrodes used in various discharge lamps such as metal halide discharge lamps.

[Conventional technology]

First, to explain this type of discharge lamp 31, as shown in FIG. Discharge lamp electrodes 34, 34 are opposed to each other, and by applying a voltage between the electrodes 34, 34, an arc is generated in the gap and light is emitted by mercury vapor. Here, the other end side facing the discharge lamp electrodes 34, 34 is connected to a molybdenum foil 36, 35, etc., and serves as a lead-in wire. Next, to describe the method for manufacturing the discharge lamp electrode 34, as shown in FIG.
Alternatively, as shown in FIG. 6, the discharge lamp electrode 34 is housed in a small container 42 made of glass or the like, and heated in a hydrogen (H2) atmosphere. A method has been used in which a high-frequency heater 43 is used to heat the heater from the outside by evacuating it.

[Problem U that the invention seeks to solve]

A detailed study of the discharge lamp electrode 34 reveals that, as explained above, one end is required to have characteristics for stabilizing the generated arc, and the other end is required to have characteristics for stabilizing the generated arc. Mechanical strength is required for connection with the molybdenum foil 35. Here, in order to stabilize the arc described above, it is preferable to crystallize the discharge lamp electrode 34, but for connection, the crystallized discharge lamp electrode 34 becomes extremely brittle and has poor mechanical strength. It becomes undesirable. However, in all of the conventional treatment methods described above, heat treatment is performed uniformly over the entire surface, rather than separately treating the discharge side or the connection side. Intermediate heat treatment (specifically, 1000 to 1600°C) was performed to the extent that the temperature did not deteriorate. When considered from the other side, this does not provide satisfactory performance on both the discharge side and the connection side, and causes the problem that the overall performance of the discharge lamp 31 adopting this discharge lamp electrode 34 is unsatisfactory. This has become a problem, and solving this problem has become an issue.

[Means to solve the problem]

As a specific means for solving the above-mentioned conventional problems, the present invention provides an electrode for a discharge lamp in which a predetermined metal member is heat-treated to correct the crystal state. An electric discharge device characterized in that a discharge side end portion is formed in a sufficiently crystalline state by heat treatment at a relatively high temperature, and a connection side end portion is formed in an amorphous state by heat treatment at a relatively low temperature. Provided is an electrode for electric lamps, and in addition, as a means for realizing the same, in a method for manufacturing electrodes for discharge lamps, the electrodes for discharge lamps are manufactured by subjecting a predetermined metal member to heat treatment to correct the crystalline state. The two ends are brought into contact with each other in a vacuum atmosphere to face each other, the other end is held by a holder that also serves as a power supply part, and a current is passed through the butt part to reach a specified temperature for heat treatment. By providing a method of manufacturing an electrode for a discharge lamp, the above-mentioned conventional problems are solved.

【Example】

Next, the present invention will be explained in detail based on an embodiment shown in the drawings. First, FIG. 1 shows the heat treatment process in the manufacturing process of electrode 1 for a discharge lamp (hereinafter abbreviated as electrode 1). They are brought into contact with each other, and the other end is attached to the holder
At this time, the bell shear 11 is connected to the exhaust device 13, and the holder 12
．． 12 is connected to an external terminal 14.14. FIG. 2 shows the state of the electrode 1 explained above in more detail. By arranging it in this way, the sides brought into contact with each other become the discharge side end 1a, and are fixed to the holder 12. The other side becomes the connection side end 1b. After the electrode 1.1 is arranged as described above, the verge 1-1
The inside of 1 is evacuated to a vacuum by an exhaust device 13,
After this, current will be supplied via the external terminals 14.14. By supplying this current, the electrode 1.1 generates strong heat and becomes scorching, especially at the discharging side end 1a11a, which is a jutting portion having contact resistance. Measure the temperature from the outside of the Vershear 11 with a thermometer 15 that can measure the temperature without contact, adjust the current so that the temperature at the discharge side end 1azla is about 3000 ° C., and maintain this state for a certain period of time. After this holding, the current is cut off, and when the electrode 1.1 has appropriately cooled, air is introduced into the Vershear 11 and the electrode 1.1 is taken out. In the above embodiment, the temperature of the contact portion was measured using the thermometer 15, but if, for example, electrodes 1 of the same size are to be processed continuously, the conditions will be almost the same. Therefore, it is not necessary to measure the temperature every time, and it is naturally possible to use a management method such as keeping the applied current constant based on accumulated data. The third one shows the electrode 1 obtained by the above manufacturing process.
In the figure, the discharge side end 1a has been heated to a sufficient temperature and is in a crystalline state suitable for arc discharge, while the connection side end 1b attached to the holder 12
Due to the heat dissipation effect of the holder 12, the temperature does not reach a level that would cause a change in the crystal state, and the state at the time of manufacture of the member is maintained;
No loss of mechanical strength. That is, according to the present invention, one end of the electrode 1 is brought into contact with the other end and the other end is attached to a holder, and the heat treatment is performed by self-heating, thereby making it possible to heat the electrode 1 with a temperature gradient, thereby making it possible to heat the electrode 1 with a temperature gradient. At the same time, sufficient heating is performed to cause recrystallization, and at the same time, unnecessary heating is not applied to the connection side end 1b, so that each end is in an optimal state for each purpose. .

【Effect of the invention】

As explained above, according to the present invention, a method of manufacturing an electrode for a discharge lamp is provided in which a pair of electrodes are brought into contact with each other in a vacuum atmosphere and faced each other, and a current is passed through the abutting portion to maintain a specified temperature. , one end of the electrode, which is the contact part, is given enough temperature to create a crystalline state in the electrode to stabilize the arc, while the other end is given a temperature that does not cause denaturation. The electrode can be heated to create a temperature gradient at one end, creating the discharge side, i.e., the ideal condition for arc stability, and at the other end, the connection side. The end portion, that is, the lead-in line, can ideally produce a wide variety of conditions, and has an outstanding effect on improving the performance and productivity of discharge lamps using this type of electrode.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the heat treatment step of the method for manufacturing an electrode for a discharge lamp according to the present invention, FIG. 2 is an explanatory diagram showing the main part of the same process in an enlarged manner, and FIG. 3 is an explanatory diagram showing the electrode of the present invention. Perspective view, 4th
The figure is a cross-sectional view showing a discharge lamp in which this type of electrode is used, and FIGS. 5 and 6 are explanatory diagrams showing conventional heat treatment steps, respectively. 1B Heavy Figure 1・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・, ...., etc.・Belshear 13--Exhaust device 15--Thermometer 12--Holder 14--External terminal @2 diagram

Claims (2)

[Claims] (1) In a discharge lamp electrode in which a predetermined metal member is heat-treated to correct the crystalline state, the discharge lamp electrode has a discharge side end that has been rendered sufficiently crystalline by heat treatment at a relatively high temperature. What is claimed is: 1. An electrode for a discharge lamp, characterized in that an electrode for a discharge lamp is formed, and a connecting end portion whose amorphous state is preserved by heat treatment at a relatively low temperature. (2) In a method for manufacturing a discharge lamp electrode in which a predetermined metal member is subjected to heat treatment to correct the crystalline state, a pair of the discharge lamp electrodes are faced in a vacuum atmosphere with one end abutting against each other. A method of manufacturing an electrode for a discharge lamp, characterized in that the other end is held by a holder that also serves as a power supply part, and a current is passed through the abutting part to a specified temperature to perform heat treatment.