JPS61288361A - Electron beam welding device - Google Patents

Abstract

PURPOSE:To prevent an invasion of positive ions in a metallic vapor or gas produced at the processing position into an anode, and prevent an abnormal discharge from occurring, by furnishing a trap to apply a minus potential, between a focusing coil and the anode. CONSTITUTION:This electron beam welding device is composed of a filament 22 to generate electron beams, a cathode 50 and anode 28 through which electron beams are passed and accelerated, and a focusing coil 30 to focus electron beams. In this case, a trap 13 is added in the electron beam passage between the anode 28 and the focusing coil 30, and applied with a minus potential from a power source 36. Ions charged in minus value in a metallic vapor or gas 21 produced from a material 10 to process are trapped by the trap 13. Therefore, 50 is prevented, an abnormal discharge between the both electrodes is reduced broadly, and the processing accuracy can be improved.

Description

[Detailed Description of the Invention] Trajectory [Field of Application of the Invention] The present invention relates to electronic 4! This relates to an electron beam welding device I.

Iron [Background of the Invention] When performing electron beam welding using electronic yellow, alloy components with low vapor pressure and rust of the material.

This caused electrical discharge, which caused welding defects. A number of devices have been proposed to prevent metal vapor from entering the electron mirror, such as the method of making a narrow hole in the electron beam path as in Japanese Utility Model Application No. 51-85027, to prevent metal vapor from entering. No method has been found to prevent the intrusion of metal vapor, which focuses only on positive ions in gas components.

[Object of the Invention] The present invention was made in view of the above-mentioned circumstances, and relates to metal vapor during electron beam welding.

A filament that generates an electron beam that focuses only on positive ions in the gaseous components and can prevent metal vapor from entering the electron mirror, a cathode and an anode that follow and accelerate the electron beam, and an accelerated In an electron beam welding device that includes a focusing coil that focuses an electron beam, a trap to which a negative potential is applied is provided in the electron beam path between the focusing coil and the anode, and the positive ions generated from the processed portion of the workpiece are The cations are captured by a trap to prevent cations from entering between the anode and cathode, thereby preventing abnormal discharge between the two electrodes.

[Embodiment of the Invention] Next, an embodiment of the present invention will be described with reference to the accompanying drawings.

The accompanying drawing is a block diagram showing the configuration of an embodiment of the electron beam welding apparatus of the present invention.

In the accompanying drawings, an electron beam welding device includes a filament 22 for generating an electron beam.

An acceleration power source 26 and a cathode 50 for accelerating the electron beam generated by the filament 22. Anode 28 and cathode 50
A bias power supply 52 for controlling the voltage of It is stored in the chamber 53,
During processing, a vacuum of less than lXIO-'mxHg is maintained.

In the present invention, a trap 13 is disposed in the loop beam path between the focusing coil 30 and the anode 28.

A negative potential is applied to the trap 13 by a power source 36.

In the above configuration, when the filament 22 is heated by the DC filament power supply 24, thermionic electrons 20 are emitted from the filament 22. The thermionic electrons 20 are accelerated by an accelerating voltage applied between the filament 22 and the anode 28 using an accelerating power source 26, and are further accelerated by a focusing coil 30.
An electron beam 2 with high energy density is focused by
It becomes 0. The electron beam 20 heats and melts the surface of the workpiece 10, and welding progresses. The gases generated in the workpiece and the oxides on the surface of the alloy component 1 that easily evaporate are heated to a high temperature, rise along the electron beam 20, go straight toward the anode 28 and the cathode 50, and pass through the anode 28. ．． This causes abnormal discharge between the cathodes 50. In the present invention, since a negative potential is applied to the trap 13 for positively charged ions in the gas 21 that cause abnormal discharge, the electrostatic attraction force of the trap 13 causes the positively charged ions to be positively charged. The charged ions are trapped in the trap 13 before reaching the anode 28. Therefore, abnormal discharge can be prevented.

[Effects of the Invention] As described above, the present invention provides a trap with a simple structure in the electron girdle for die piggy beam welding, and applies a negative potential to the trap to prevent abnormal discharge of electron interference. This has the effect of greatly reducing the width and improving the processing accuracy of electron beam welding.

[Brief explanation of drawings]

The accompanying drawings are schematic diagrams showing the configuration of an embodiment of the present invention. 10... Work material, 12... Welding location, 13...
Trap 20...electron beam, 21...generated gas, 22
... filament, 26 accelerating current, 28... anode,
30... Focusing coil 36... Power supply, 50... Cathode, 52... Bias power supply - 53... Vacuum chamber.

Claims (1)

[Claims] In an electron beam welding device comprising a filament that generates an electron beam, a cathode and an anode that accelerate through the electron beam, and a focusing coil that focuses the accelerated electron beam, there is a negative electrode in the electron beam path between the focusing coil and the anode. An electron beam welding device characterized by being provided with a trap to which a potential of is applied.