Resistance spot-welding tongs electrode abrasion state monitoring method and device

Abstract

The invention discloses a resistance spot-welding tongs electrode abrasion state monitoring method and device. The method includes the following steps that S1, a transient resistance changing curve between welding tongs electrodes during resistance spot-welding is detected; S2, the duration in the transient resistance changing curve in a rising stage is judged according to the transient resistancechanging curve between the welding tongs electrodes during resistance spot-welding; and S3, the duration in the transient resistance changing curve in a rising stage is compared with a time thresholdvalue, and when the duration in the transient resistance changing curve in a rising stage is smaller than a time threshold value, a welding tongs electrode abrasion repair prompt is given. By means of the method, the abrasion state of the electrodes can be accurately monitored under the condition of no stop of production, and the production efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of vehicle manufacturing, in particular to a method and a monitoring device for monitoring the wear state of electrodes of resistance spot welding tongs. Background technique [0002] In the process of resistance spot welding of body-in-white, after a certain number of welding spots are welded, a certain amount of oxide will be formed on the electrode surface of the electrode cap, which will seriously affect the welding quality, and the electrode surface needs to be re-grinded. Resistance spot welding can be performed again to ensure the quality of resistance spot welding. [0003] In the automatic body production line, under normal circumstances, a welding tong needs to weld different grades of metal materials at different times. For example, it may successively weld sheet metals of various materials such as low alloy steel, high strength steel, and hot-formed steel. This makes it difficult for technicians...

AI Technical Summary

Problems solved by technology

However, since this specified number of times is set based on past experience, this method will cause the following problems. During the grinding cycle of the welding tongs electrode, it is possible that the welding tongs electrode has reached the required number of welding times. In this way, the electrode of the welding tongs will work with a disease, which will affect the quality of the product. It is also possible that when the specified number of times of welding tongs is reached, the electrode of the welding tongs has not yet reached the state of needing to be repaired. Grinding, which will shorten the service life of the electrode of the welding gun and increase the production cost

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