Apparatus for stress relieving springs and the like

Abstract

Apparatus comprising a rotary supporting table for moving circumaxial series of work holders in a predetermined circular path. Each work holder comprises an upright pin adapted to receive on and about itself a coil spring and a base member. The base member takes the form of an electrically conductive electrode part. At a loading station, springs are deposited successively on the pins and the table is indexed to move the pins and springs to a stress relieving station. Prior to the stress relieving station, a rotary brush engages the springs and indexes them about their pins to bring an end surface of an end coil into engagement with a small vertical abutment on the base member. The base members have inclined seating surfaces for the side surfaces of the end coils of the springs. At the stress relieving station, an upper electrode is moved into engagement with an upper-most coil of the spring to set the spring slightly and a second part of a lower electrode is moved into engagement with the electrically conductive base member or first electrode part. The spring is then resistance heated for stress relief and thereafter passes through a cooling tunnel having an air blower associated therewith. At a spring setting station, a vertically reciprocable ram engages each spring at an upper portion and compresses the spring about its supporting pin whereby to set the same. An unloading device is provided at an unloading station and comprises a caliper type spring gripping device which is slidable vertically and swingable horizontally through approximately 90.degree.. The gripping device engages a spring and lifts the same from its supporting pin to thereupon swing it horizontally for discharge into an appropriate discharge chute.