Pneumatically-operated spool holder for wire-stranding machine - with locking device automatically disengaged prior to spool release

摘要

A spool holder for high-speed stranding machines from which the spools can be automatically released by hydraulic or pneumatic retraction of the axle stub has a mechanical locking device to prevent accidental release of the spool which can be disengaged before retraction of the axle stub commences, to prevent jamming of the mechanism. The locking element may be held in engagement by a secondary piston which simultaneously blocks the operating circuit of the retraction system, preventing activation until after the locking element has been disengaged. Alternatively, a single-piston system may be used wherein the initial movement of the piston disengages the locking element, the release of the spool being effected by the further movement of the piston. The mechanism provides a simple, reliable locking action which is quickly released without difficulty.