JPH0275474A - Hole holding type resistance welding method for materials to be welded - Google Patents

Abstract

PURPOSE:To carry out accurate positioning and to improve strength by providing round holes with the same dia. on both materials to be welded and fitting both materials to be welded to each other to position these materials by a round bar which also serves for positioning to fit these round holes and welding these materials with the round bar at the same time at the almost central position of the round holes. CONSTITUTION:The round holes 1a and 2a with the same dia. are provided to both materials 1 and 2 to be welded and a positioning pin 4 to fit closely these holes is provided separately. After the pin 4 is inserted into the round holes 1a and 2a to position the materials 1 and 2 to be welded, the pressure is applied to the materials to be welded and the positioning pin and an electric current is allowed to flow to these by an upper electrode 3a and a lower electrode 3b and the materials to be welded and the positioning pin are welded integrally. A cross-sectional shape of this joining part can be subjected to resistance welding capable of holding airtightness without a waste hole like nuggets 5 of a welded zone. By this method, accurate positioning is carried out and shear strength is improved and workability can be improved.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to improvements in methods for resistance welding sheet metal parts.

[Conventional technology]

Conventionally, in this type of resistance welding, welding has been performed by positioning the workpiece using a positioning jig suitable for the shape of the workpiece. For example, as shown in FIGS. 4 and 5, after positioning the workpieces 6 and 7, which are the objects to be welded, using a positioning jig suitable for the workpieces, pressure is applied by the upper electrode 3a and the lower electrode 3b. They were joined by resistance welding by applying current and applying current.

[Problem to be solved by the invention]

As mentioned above, conventionally, resistance welding of sheet metal has been carried out by providing a positioning jig for each shape depending on the shape of the workpiece, or by performing resistance welding by positioning using a hole for positioning. If a jig is not used, there will be large variations in positioning accuracy, leading to a decline in quality.In particular, products that require high precision almost always require a positioning jig, which causes high costs. . Furthermore, there are many products in which it is not possible to make a hole for positioning, and generally there are problems such as there being no choice but to supply a positioning jig for positioning.

[Means to solve the problem]

In the hole-stop resistance welding method for objects to be welded according to the present invention, round holes of the same diameter are bored in both objects to be welded, and a round rod serving as a positioner that fits into the round holes without any gaps is used to weld the objects to be welded. It is characterized in that the objects to be welded and the round bar are simultaneously welded at approximately the center position of the round hole and the round bar by fitting them together and positioning them.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

1 and 2 are sectional views before and during welding of an embodiment of the present invention, and FIG. 3 is an enlarged sectional view showing a joint according to this embodiment.

In this embodiment, round holes 1a and 2a of the same diameter are bored in both of the two workpieces 1.2 to be welded, and the round holes 1a and
A positioning pin 4 that fits into the pin 2a without a gap is separately provided.

After positioning the workpieces 1 and 2 by inserting the positioning bins 4 into the round holes la and 2a, the upper electrode 3a and the lower electrode 3b
By applying pressure to the workpieces 1.2 and the positioning bottle 4 and passing a current, the workpieces 1, 2 and the positioning bottle 4 are
A resistance welding method is obtained in which the parts are welded together. An example of the cross-sectional shape of the joint is shown in FIG. 3, and resistance welding, such as the nugget 5 which is the welded part, can be performed without any holes and which can maintain airtightness.

〔Effect of the invention〕

As explained above, the present invention enables accurate positioning of the workpiece of a sheet metal part and improvement of the welding shear strength by welding the workpiece at the positioning bin, and eliminates and cures waste holes. Eliminating the need for tools has the effect of significantly improving resistance welding workability.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of an embodiment of the present invention before and during welding, FIG. 3 is an enlarged cross-sectional view of a joint according to this embodiment, and FIGS. 4 and 5 are FIG. 3 is a sectional view showing an example of a conventional resistance welding method before and during welding. 1.2.6.7...Workpiece, 3a...-Upper electrode,
3b...lower electrode, 4...positioning bottle, 5...nugget.

Claims (1)

[Claims] A round hole with the same diameter is drilled in both of the objects to be welded, and the objects to be welded are positioned using a round bar that also serves as positioning and fits into the round hole without any gaps. A method for resistance welding of objects to be welded using a hole stopper, characterized in that the objects to be welded and the round rod are simultaneously welded at substantially the center of the rod.