JPH04105771A - Welding method - Google Patents

Abstract

PURPOSE:To obtain sufficient welding strength without leaving welding traces in performing resistance welding on a sheet metal and a metallic shaft by laminating an electrical insulating layer on a sheet metal. CONSTITUTION:Members to be welded are constituted by laminating the insulating layer 5 by the sheet metals 1 and 2. When a welding current is carried between a chuck 5 and a welding electrode 6 while the metallic shaft 4 which is the member to be welded held on the chuck 5 being pressed by proper pressurizing force on the surface of the sheet metal 1, a contact part between the sheet metal 1 and the metallic shaft 4 is subjected to resistance heating and both are molten and welded together. At this time, since the sheet metal 2 is insulated electrically by the insulating layer 3, the welding current is not carried to the sheet metal 2. Accordingly, since this is not heated, softening or strength decrease of material is not caused and accordingly, even if the metallic shaft 4 is pressurized, the welding traces are not left.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of resistance welding a steel plate and a bolt or nut, a brass plate and a copper shaft, etc.

[Conventional technology]

Conventionally, resistance welding between a thin metal plate and a metal shaft has been carried out using the following method. In FIG. 3, the chuck 5 and the welding electrode 60 are pressed while pressing the metal shaft 4, which is the welding member carried by the chuck 5, against the surface of the metal thin plate 10, which is the welding member held on the welding pedestal 7, with an appropriate pressure. When a welding current is passed between them, the contact portion between the metal thin plate 1 and the metal shaft 4 is heated by resistance, and the two parts melt together, completing the welding. In such welding methods, it is generally known that the welding strength of the joint varies depending on the pressure, welding current, and material of the parts to be welded, and requirements such as welding accuracy and appearance of the welded part vary. Welding conditions were determined based on quality characteristics. However, in order to stably obtain welding strength that does not cause any practical problems, it is necessary to increase the pressure and welding current. A welding mark 8 remains on the surface facing the welded part.The reason why the welding mark remains is that the welding current heats the thin metal plate near the welded part, and pressurizing force is applied to the area where the material strength has decreased, causing the thin metal plate to deform. If these welding marks are reduced to a level that does not pose a problem in terms of appearance, the welding strength will decrease, making it difficult to set the conditions.

[Problem to be solved by the invention]

As mentioned above, with conventional technology, it is difficult to achieve both the appearance quality of leaving welding marks and the functional quality of welding strength. The purpose of the present invention is to solve this problem by providing a resistance welding method that provides high welding strength and does not leave any welding marks. be.

[Means to solve the problem]

The welding method of the present invention is a method of resistance welding a thin metal plate and a metal shaft, and is characterized in that the thin metal plate has a structure in which an electrically insulating layer is laminated in the middle.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings. In FIG. 1, the member to be welded has a structure in which an insulating layer 6 is laminated with thin metal plates 1 and 2. Specifically, the material for the thin metal plate is copper, brass-steel, nickel silver, etc., and the material for the insulating layer is epoxy, acrylic, or rubber adhesive, etc., which also serves to bond the thin metal plates together. . In such a thin metal plate structure, since the thin metal plates 1 and 2 are electrically insulated, a metal shaft 4, which is a welding member supported by a chuck 5, is attached to the surface of the thin metal plate 1 with an appropriate pressure. When a welding current is passed between the chuck 5 and the welding electrode 60 while pressing them, the contact portion between the thin metal plate 1 and the metal shaft 4 is heated by resistance, and the partners melt and weld. At this time, since the thin metal plate 2 is electrically insulated by the insulating layer 6, no welding current flows through the thin metal plate 2. Therefore, since no heating is performed, no softening or reduction in strength of the material occurs, and therefore no welding marks remain even if the metal shaft 4 is pressurized. In the above-mentioned embodiments, an insulating layer is laminated between the thin metal plates to be welded to prevent the welding current from flowing to the non-weld side, but the following examples are also available. FIG. 2 shows an example of this, in which the welded member has a laminated structure of a thin metal plate 1 and a thin metal plate 2 made of different materials, and the thin metal plate 1 has excellent weldability with a metal shaft 4, which is a welding member. By selecting the material and selecting a material with high mechanical strength for the thin metal plate 3, it is possible to weld without leaving any welding marks.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to obtain sufficient welding strength without leaving welding marks, so it is possible to perform resistance welding on ornaments whose appearance is a problem or thin plates after painting. has.

゛°゛°°°°゛°Chuck ・・・・・・・・・Welding electrode ・・・・・・・・・Welding stand ・・・・・・・・・Welding marks that's all

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention. FIG. 2 is a sectional view showing an embodiment of the present invention. FIG. 3 is a sectional view showing a conventional welding method. FIG. 4 is a sectional view showing welding results obtained by a conventional welding method. 1・・・・・・・・・・・・・Thin metal plate 2・・・・・・・・・Thin metal plate 5...Insulating layer 4・・・・・・・・・Metal shaft

Claims (1)

[Claims] A welding method for resistance welding a thin metal plate and a metal shaft, characterized in that the thin metal plate has a structure in which an electrically insulating layer is laminated in the middle.