JPS62270294A - Electrode for plasma cutting torch - Google Patents

Abstract

PURPOSE:To prevent the falling off of a cathode material from an electrode base material by inserting the cathode material to the hole having the diameter slightly smaller than the outer diameter of the cathode material of the end part of the electrode base material consisting of a copper material and pressurizing the outer periphery of the end part of the electrode base material. CONSTITUTION:The hole with a hole diameter phid1 at the end part center is pierced on the base material 21 consisting of a copper or copper alloy. The cathode material 22 having its outer diameter phid2 slightly larger than the hole diameter phid1 is then inserted into the hole of the base material 21. The outer periphery of the end part of the base material 21 is then mechanically pressed to a force (f) in the center direction and the electrode of a torch is completed by making the end part finishing hole diameter phid3 of the base material 21 smaller than the outer diameter phid2 of the cathode material 22. With this composition the falling off of the cathode material 22 is prevented and the burning of the electrode and breakdown of the power source for cutting can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION 3. DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a plasma cutting torch using a working gas.

Prior Art Plasma arc cutting equipment using conventional working gas is the fourth
9 is a compressor that compresses the working gas and sends it to the tip of the torch, 1o is a regulator that adjusts the secondary pressure of the working gas to a constant value, 11 is a plasma cutting power source for supplying power, 12 is the base material 18 and power supply 1
1 is a power cable connecting 1, and 13 is a plasma cutting torch. The torch 13 has a built-in electric lamp and a cooling cable 14 that sends working gas to the tip of the torch. Torch switch cable 16. Consists of a pyro cable 16 that carries a high frequency to improve arc start,
The structure of the tip 17 of the cutting torch 13 is shown in FIG. 3 is an electrode with a cathode material such as zirconium or hafnium embedded in the tip, 4 is electrode 3 and tip 5
5 is an orifice having a small diameter hole for electrically insulating the plasma arc, dividing the working gas supplied from the cable, and generating a swirling flow that constricts the plasma arc; 5 supplies the plasma arc to the base material; Chip, 6 is chip 5. Orifice 4. A guide nozzle is screwed into and fixed to the threaded part of the electrode 3, a nozzle 7 prevents the conductive part from being exposed to the outside, and a working gas 8 is used for cooling and constricting the plasma arc.

The structure of the electrode 3 at the tip of the torch is shown in FIG.

That is, in the conventional electrode 3, a hole diameter φd1 is formed at the end of an electrode base material 1 made of copper or a copper alloy, and this hole diameter is equal to the outer diameter φ of a cathode material such as zirconium or hafnium.
Base material 1 is made smaller by 0.051 to 0.100 than d2.
Cathode material 2 was inserted into the

For this reason, the bottom diameter φd4 of the cathode material becomes smaller and it is inserted in a tapered state, and when a plasma arc is generated, the expansion coefficient of the cathode material 2 is larger than that of the base material 1. There was a phenomenon in which the selection fell. When the cathode material 2 falls off like this, the electrode 3. blood.

This resulted in burnout of the plug 5 and damage to the power supply 11, making it impossible to disconnect.

Means for Solving the Problems In order to solve the above problems, in the electrode of the plasma cutting torch of the present invention, the diameter of the hole drilled in the center of the end of the base material is slightly smaller than the outer diameter of the cathode material. Then, insert a 1 m cathode material into the hole of the base material, mechanically pressurize the outer circumference of the end of the base material toward the center, and make the finished diameter of the end of the base material smaller than the outer diameter of the cathode material. It also becomes smaller.

action With the above configuration, the cathode material does not fall off the base material.

Example An embodiment of the present invention will be described below.

FIG. 1 shows the electrodes of a plasma cutting torch, with reference numeral 21 a base material made of copper or a copper alloy, and 22 a cathode material made of a metal such as zirconium or nitrogen, forming an electron emitting surface.

In the base material 21, a hole with a diameter φd1 is first drilled in the center of the end, and then the outer diameter φd2 of the cathode material is 0.01 smaller than the hole diameter φd1.
A cathode material 22 that is 0 to 0,050 mm larger is inserted into the hole in the base material 21. Next, the outer periphery of the end portion of the base material 21 is pressurized in the central direction f, and the finished diameter φd5 of the end portion of the base material 22 is made smaller than the outer diameter φd2 of the cathode material 22 by 1-.

The above configuration prevents the cathode material 22 from being removed and falling, thereby preventing burnout of the electrode and damage to the cutting power source.

Note that the outer diameter φd2 of the cathode material 22 is the hole diameter φd1 of the base material 21.
From 0. oo1-0, OO9MM Major Key 3 In this case, the contact force between the base material 21 and the cathode material 22 will be weak, and the cathode material 22 will easily fall off, which is not preferable.

Also, the outer diameter φd2 of the cathode material 22 is the hole diameter φd1 of the base material 21.
If it is 0.051 to 0.100 mm larger than that, a tapered state of the cathode material 22 will occur due to the insertion of the cathode material 22, and when a plasma arc is generated, the cathode material 22 will not come out easily due to the difference in expansion coefficient. Immediately, I don't like it.

Effects of the Invention As described above, according to the present invention, it is possible to prevent the cathode material from falling out, thereby preventing burnout of the electrode and chip and damage to the cutting power source.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an electrode of a plasma cutting torch showing an embodiment of the present invention, Fig. 2 is a sectional view of an electrode of a conventional plasma cutting torch, and Fig. 3 is a sectional view of main parts of a general plasma cutting torch. FIG. 4 is a schematic perspective view of a general plasma cutting machine. 21... Base material, 22... Cathode material. Name of agent: Patent attorney Toshio Nakao and 1 other person 3-electrode +--one software 4-pronged 7--north 8-11i gamma first sword 9---gonbu Lno 1-1Q -、1 hour

Claims (1)

[Claims] In the electrode of a plasma cutting torch, in which a metal such as zirconium or hafnium is embedded as a cathode material in the end of a base material made of copper or copper alloy to form an electron emitting surface, a hole is drilled in the center of the end of the base material. The diameter of the cathode material is made slightly smaller than the outer diameter of the cathode material, the cathode material is inserted into the hole of the base material, and the outer periphery of the end of the base material is mechanically pressurized toward the center. An electrode for a plasma cutting torch, characterized in that the finished end diameter is smaller than the outer diameter of the cathode material.