RESISTANCE WELDING METHOD

• US 20110180518A1
• Filed: 01/26/2011
• Published: 07/28/2011
• Est. Priority Date: 01/28/2010
• Status: Abandoned Application

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: HASEGAWA, Eisaku, TAKEISHI, Katsumi, MAKITA, Taku, AOKI, Yushi, KANEKO, Mitsugu
• Application Number:
  US13/014,378
• Publication Number:
  US 20110180518A1
• Time in Patent Office: Days
• US Class Current: 219/108
• CPC Class Codes: B23K 11/115 by means of two electrodes placed opposite one another on both sides of the welded parts
• CPC Class Codes: B23K 11/253 the measured parameter being a displacement or a position

Abstract

A resistance welding method, which resistance-welds a pair of workpieces by gripping the workpieces with a pair of electrode tips under a prescribed welding pressure, and supplies a welding current through the electrode tips to the workpieces, includes the steps of detecting a change in an amount of expansion of a nugget produced in the workpieces, along a direction in which the electrode tips grip the workpieces therebetween, determining whether the detected change is smaller than a threshold value or not, and gradually increasing the welding current flowing through the workpieces after the detected change is judged as being smaller than the threshold value.

Claims

1. A method of resistance-welding a pair of workpieces by gripping the workpieces with a pair of electrode tips under a prescribed welding pressure, and supplying a welding current through the electrode tips to the workpieces, comprising the steps of:

detecting a change in an amount of expansion of a nugget produced in the workpieces, along a direction in which the electrode tips grip the workpieces therebetween;

determining whether the detected change is smaller than a threshold value or not; and

gradually increasing the welding current flowing through the workpieces after the detected change is judged as being smaller than the threshold value.

2. The method according to claim 1, wherein the step of gradually increasing the welding current comprises the step of increasing the welding current depending on the detected change.

3. The method according to claim 1, further comprising the step of lowering the welding pressure applied to the workpieces after the detected change is judged as being smaller than the threshold value.

4. A method of resistance-welding a pair of workpieces by gripping the workpieces with a pair of electrode tips under a prescribed welding pressure, and supplying a welding current through the electrode tips to the workpieces, comprising the steps of:

detecting a change in an amount of expansion of a nugget produced in the workpieces, along a direction in which the electrode tips grip the workpieces therebetween;

determining whether the detected change is smaller than a threshold value or not; and

lowering the welding pressure applied to the workpieces after the detected change is judged as being smaller than the threshold value.