Resistance welding method and resistance welding jig

摘要

In resistance welding, an end portion and a flange portion are welded together at contact surfaces thereof by applying a voltage between a first electrode and a second electrode while an inner casing and a main metal piece are pressed in directions toward each other. When a shearing stress due to the pressure is applied to a ceramic guide pin, the guide pin is more resistant to wear compared to a phenolic resin guide pin. In addition, a clearance is between a large-diameter portion of the guide pin and an inner surface of a guide-pin insertion hole. Accordingly, the guide pin is capable of tilting in the radial direction, so that the guide pin can tilt so as to partially absorb the shearing stress. Therefore, the guide pin is more resistant to breakage compared to a guide pin made of ceramic that is not capable of tilting.

主权项

1. A resistance welding method for welding conductive cylindrical first and second members to each other in a coaxial manner by bringing end portions of the cylindrical first and second members into contact with each other, the resistance welding method comprising:
providing a first electrode having an insertion hole and a columnar guide pin insertable into the insertion hole; positioning the guide pin and the cylindrical first member by inserting the guide pin and the cylindrical first member into the insertion hole such that the insertion hole, the cylindrical first member, and the guide pin are coaxial with each other, such that the first electrode contacts the cylindrical first member, such that the guide pin extends through the cylindrical first member, and such that a portion of the cylindrical first member to be welded and a portion of the guide pin project from the insertion hole; positioning the cylindrical second member by inserting the guide pin into the cylindrical second member such that the end portions of the cylindrical first and second members contact each other, such that the cylindrical first and second members are coaxial with each other, and such that the cylindrical second member does not contact the first electrode, the guide pin being made of ceramic and a clearance being disposed between the guide pin and an inner surface of the insertion hole while the guide pin is inserted in the insertion hole, the clearance enabling the guide pin to tilt in a radial direction of the insertion hole while contact is maintained between the cylindrical first and second members and a current is conducted during welding; and welding the cylindrical first and second members to each other at contact surfaces thereof by positioning a second electrode such that the second electrode contacts the cylindrical second member and does not directly contact the first electrode and applying a voltage between the first and second electrodes to conduct the current through the contact surfaces of the cylindrical first and second members while the cylindrical first and second members are pressed in directions toward each other.