JP2008012587A - Tip structure of gun arm - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the tip structure of a gun arm in which there is little concern about occurrence of electrolytic corrosion since a bottomed bush is arranged into the bore formed at the tip side of a gun arm made of an aluminum alloy. <P>SOLUTION: An electrode holder 2 made of a copper alloy having an electrode 4 at the distal end thereof is inserted and fixed into the bore 3 formed at the tip side of the gun arm 1 made of an aluminum alloy, and a flow path 5 of a cooling water is formed in the electrode holder to compose the tip structure of the gun arm. The bottomed bush 6 made of copper or a copper alloy is fitted into the bore formed in the gun arm to cover the outer periphery of the electrode holder in the bore. Further, the inflow and outflow parts 10 and 11 for the cooling water are made in a base 8 formed in the bush, and those flow parts 10 and 11 are connected to the cooling water flow path in the electrode holder. Thereby, an electrolytic corrosion-preventing means 15 is applied to the outer peripheral face of the bush. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  In the present invention, an electrode holder made of a copper alloy having an electrode attached to the tip is inserted and fixed in a hole formed on the tip side of an aluminum alloy gun arm, and a cooling water flow passage is formed in the electrode holder. It relates to the tip structure of the gun arm.

  Conventionally, a gun alloy electrode holder made of copper alloy with an electrode attached to the tip is inserted and fixed in a hole formed on the tip side of an aluminum alloy gun arm, and a cooling water flow passage is formed in the electrode holder. In the tip structure of the arm, the electrode holder is fixed to the gun arm by screwing, and for cooling the electrode, an inflow / outlet member for cooling water is provided in the hole of the gun arm, and the inflow / outlet member and the electrode holder There is something that connects both with a gap between them. (For example, refer to Patent Document 1).

Japanese Patent Laid-Open No. 56-168773.

  By the way, in the above conventional example, since the electrode holder is directly fixed to the gun arm and there is a place where the cooling water directly contacts the gun arm, the tip side of the gun arm made of aluminum alloy is used. There is a high possibility that electric corrosion will occur on the surface of the hole formed in this.

  The present invention has been made in view of such problems of the prior art, and the object of the present invention is to place a bottomed bush in a hole formed on the tip side of an aluminum alloy gun arm. Therefore, it is intended to provide a gun arm tip structure that is less likely to cause electric corrosion.

  To achieve the above object, the gun arm tip structure according to the present invention has a copper alloy electrode holder with an electrode attached to the tip inserted into the hole formed on the tip side of the aluminum alloy gun arm. In the gun arm tip structure in which a cooling water flow passage is formed in the electrode holder, a bottomed bush made of copper or copper alloy is fitted into the hole formed in the gun arm, And the cooling water inflow / outflow portion is formed in the base formed on the bush, the inflow / outflow portion is connected to the cooling water flow passage in the electrode holder, and the outer peripheral surface of the bush is electrically connected. It is characterized by providing anti-corrosion means.

  In the first aspect of the present invention, a bottomed bush made of copper or a copper alloy is fitted into a hole formed in the gun arm, and the outer periphery of the electrode holder in the hole is covered with the bush, and formed on the bush. A cooling water inflow / outflow portion is formed in the base, and the inflow / outflow portion is connected to a cooling water flow passage in the electrode holder, and an electric corrosion prevention means is provided on the outer peripheral surface of the bush. -The gun arm tip structure is less likely to cause electrolytic corrosion on the surface of the hole formed on the tip side of the arm.

  A copper alloy electrode holder with an electrode attached to the tip is inserted and fixed in a hole formed on the tip side of the aluminum alloy gun arm, and a cooling water flow passage is formed in the electrode arm. In the tip structure, a bottomed bush made of copper or a copper alloy is fitted in a hole formed in the gun arm, and the outer periphery of the electrode holder in the hole is covered with the bush, and cooling water is applied to a base formed in the bush. A gun arm tip structure in which an inflow / outflow portion is formed, the inflow / outflow portion is connected to a cooling water flow passage in the electrode holder, and an electrolytic corrosion preventing means is provided on the outer peripheral surface of the bush.

An embodiment of the present invention will be described with reference to FIGS.
In the figure, reference numeral 1 denotes a gun arm. The gun arm 1 has an electrode holder 2 fixed to the tip side thereof, and serves as a fixed arm, a movable arm or a swing arm of a welding machine. It is used.

  The gun arm 1 is made of an aluminum alloy for reasons such as reducing weight and facilitating processing, and is provided with a hole 3 for inserting and fixing the electrode holder 2 on the tip side thereof.

  The electrode holder 2 is made of a copper alloy, and an electrode 4 is attached to the tip side of the electrode holder 2 and a cooling water flow passage 5 for cooling the electrode 4 is formed along the central axis.

  Reference numeral 6 denotes a bottomed bush. The bottomed bush 6 is made of copper or a copper alloy and is fitted into the hole 3, and the electrode holder 2 is inserted into the cylindrical portion 7. In addition, a bolt mounting hole 9 for fixing the bottomed bush 6 to the gun arm 1 made of aluminum alloy is formed in the base 8 of the bottomed bush 6, and cooling is provided in the base 8. A water inflow portion 10 and an outflow portion 11 are formed.

  The cooling water inflow pipe 12 from the inflow portion 10 passes through the cooling water flow passage 5 of the electrode holder 2 and is configured to feed the cooling water into the cooling water passage 13 of the electrode 4 at the tip of the electrode holder 2. ing. Further, the outflow portion 11 is connected to a cooling water outflow passage 14 formed on the outer periphery of the cooling water inflow pipe 12.

  Further, the entire surface of the bottomed bush 6 that contacts the gun arm 1 is subjected to an anti-corrosion treatment 15 such as application of an anti-corrosion agent, plating, soldering, or silver brazing.

  Reference numeral 16 denotes a seal ring for preventing leakage of cooling water. Reference numeral 17 denotes a split formed on the upper end side of the gun arm 1. By tightening the split 17 with a bolt 18, The electrode holder 2 and the bottomed bush 6 are firmly fitted to the gun arm 1.

  The tip structure of the gun arm as described above is such that the electrode holder 2 having the electrode 4 attached to the tip and the cooling water inflow pipe 12 disposed in the cooling water flow passage 5 is first subjected to the electrolytic corrosion prevention treatment 15. The bottomed bush 6 is fitted into the cylindrical portion 7 of the bush 6 and inserted into the hole 3 formed in the gun arm 1, and then the bolt 19 is screwed into the bolt mounting hole 9. Then, the bottomed bush 6 is fixed to the gun arm 1 by the bolt 19, and then the bolt 18 is tightened so that the electrode holder 2 and the bottomed bush 6 are firmly fitted to the gun arm 1.

  In this gun arm tip structure, a welding current is supplied from the aluminum alloy gun arm 1 to the electrode 4 through the bottomed bush 6 and the electrode holder 2 during the welding operation, and the electrode 4 is cooled by cooling water. However, the surface of the bottomed bush 6 in contact with the aluminum alloy gun arm 1 is subjected to an electrolytic corrosion prevention process 15 and the flow path of the cooling water is provided in the bottomed bush 6. Since the cooling water does not come into contact with the gun arm 1 made of aluminum alloy, there is no possibility that electric corrosion will occur on the surface of the hole 3 formed on the tip side of the gun arm made of aluminum alloy. Become.

It is principal part sectional drawing of the Example of the front-end | tip structure of the gun arm which concerns on this invention. It is AA sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gun arm 2 Electrode holder 3 Hole formed in gun arm 4 Electrode 5 Cooling water flow path 6 Bottomed bush 7 Bush cylindrical part 8 Bush base 10 Cooling water inflow part 11 Cooling water outflow part 15 Electric corrosion Prevention processing

Claims (1)

A copper alloy electrode holder with an electrode attached to the tip is inserted and fixed in a hole formed on the tip side of the aluminum alloy gun arm, and a cooling water flow passage is formed in the electrode arm. In the tip structure, a bottomed bush made of copper or copper alloy is fitted in a hole formed in the gun arm, and the outer periphery of the electrode holder in the hole is covered with the bush, and cooling water is formed on a base formed in the bush. A tip end structure of a gun arm, wherein an inflow / outflow portion is formed, the inflow / outflow portion is connected to a cooling water flow passage in the electrode holder, and an electrolytic corrosion preventing means is provided on an outer peripheral surface of the bush.