Electrically-driven cam-actuated tool clamp

Abstract

A mechanical clamping device adapted to engage and secure the upper tooling of a welding knee. The clamping device is motor driven such that several clamping devices can be simultaneously and synchronously operated to engage, align and secure the upper tooling from a remote location. The clamping device includes a clamping lever actuated by a cam mechanism. The clamping lever has an upper end provided with a cam follower, a lower engagement end for engaging the tooling, and a journalling region. The engagement end is adapted to closely engage a corresponding feature on the tooling. The journalling region of the clamping lever is slidably journalled in a bushing which includes a biasing member for biasing the cam follower against the cam mechanism. The clamping lever is pivotably attached by the bushing to the cam mechanism which serves to both rotate the clamping lever and bushing together and stroke the clamping lever within the bushing to secure the upper tooling to the welding knee. The cam mechanism rotates the clamping lever during a positioning stage of the clamping device, and then sequentially strokes the clamping lever to engage the engagement end of the clamping lever with the upper tooling during an engagement stage. The cam mechanism is driven by a motor through a worm gear arrangement which is capable of resisting an overrunning condition induced by the weight of the upper tooling on the lever and cam arrangement.