welding machine, programmed, propagating velocity of the welding head

摘要

A welding machine includes a programming device to move a welding head relative to horizontal main X and Y axes, and to rotate the head about a vertical C axis. A sensor is connected to rotate with the welding head on a rotator. A sine cosine resolver is mounted on the rotator so that its shaft is geared to the rotator gear. Deviations from the programmed path which may occur in the weld groove are sensed by the sensor, which in turn causes the resolver output to drive a slide mechanism which defines deviation axes Xd and Yd and which causes the weld head to move from its programmed path to the desired corrected path, when needed. The resolver includes a deviation correction control rotor winding and a second rotor winding, the latter selectively impressing signals on the Xd and/or Yd slide mechanism drive to cause the welding head to effectively change speed independent of the program or of the existence of any deviation. In welding machines for simultaneously joining multiple pairs of workpieces, the speed control makes it possible to compensate for variations in gap widths.