Apparatus and process for manufacturing a frame part by welding plastic profiles

摘要

A preliminary stroke determining stop(32) for a working slide(8) acts in conjunction with a mandrel(36) activated by a secondary drive unit(34) to set an approximate initial position for the slide. A primary drive unit(10) moves the slide from the initial position into one of several final working positions set by switchable stroke stops(14,16,18). The mandrel(36) acts against the working movement of the pneumatic primary drive unit(10). A damper(38) is fitted to the coarse stroke stop(32). The mandrel(36) comprises a spindle is driven by a stepper motor(34) and a position sensor(52) is assigned to the mandrel. Primary and secondary drive units are linked to a common control unit(50). The control unit moves the mandrel away from the coarse stroke stop to allow the remaining working strokes of the slide to be accurately controled by the stroke stops(14,16,18). A chip in the control unit stores data such as time-stroke curves for controling the mandrel movement depending on the operational step being performed and/or on the characteristic parameters for the profiles, e.g. material properties. An independent claim is included for a process for welding plastic profiles(2) into frames in which a plastic profiles are moved into predetermined working positions by a slide and stroke stops. When the slide(8) approaches a set position the coarse stroke stop strikes the mandrel and the latter is activated to move away from the stop and thus allow further travel of the slide to its final preset position.