SEQUENCE CONTROLLER FOR WORKPIECE-CLAMPING DEVICE FOR SPOT WELDING

PROBLEM TO BE SOLVED: To provide a sequence controller for a workpiece-clamping device for welding, a controller that makes setting by a switching operation possible for desired operating conditions of sequential control. SOLUTION: In the sequence controller, in the sub units 2-4 attached to the master unit 8, there are installed channel instructing switches S23, 24 for selecting a clamp channel, a channel total number instructing switch S25, and welding spot number instructing switches S42, 43. In addition, the sequence controller is equipped with a channel initializing means 21 for preparing channel setting data in response to these setting operations, a clamp-confirming means 31 for sending out a clamp-confirming signal to the master unit 8 in response to a clamp detection signal that detects an assigned clamp piece 29 closing for each clamp channel operation, and a welding spot number-confirming means 41 that prepares welding spot number data in response to the setting operation of the welding spot number instructing switch, that counts the welding spot detection signals of a spot welding machine 38, and that sends out a welding spot number-confirming signal to the master unit 8 upon confirming agreement of the welding spot numbers. COPYRIGHT: (C)2008,JPO&INPIT