ELECTRODE HOLDER AND ELECTRIC SENSOR

摘要

It is known to provide a welding electrode holder with a sensor for measurement of the force with which the electrode is pressed against a workpiece. The sensor is connected to an electrical circuit controlling welding. In this invention, the sensor comprises a light guide connected to the electrode holder so that elastic deformation of the holder corresponding to the electrode force changes the optical characteristics such as transmission of the light guide. The circuit is responsive to these changes in the optical characteristics of the light guide. This allows measurement of the electrode force close to the point at which the force is applied and allows changes in the electrode force to be measured during the course of welding. The sensor is robust and avoids problems of interference by electromagnetic fields.