Patent ID: 7056078

Claim:
A load-handling clamp adapted to be mounted upon the lifting apparatus of a lift truck, comprising: (a) a frame adapted to be mounted upon said lifting apparatus so as to be selectively movable vertically by said lifting apparatus; (b) first and second opposing clamping assemblies mounted upon said frame, the first clamping assembly comprising at least a pair of clamp arms movable separately from each other relative to said frame selectively toward and away from the second clamping assembly; (c) a pair of bidirectional fluid power actuators each capable of moving a respective one of said pair of clamp arms selectively either in a closing movement toward said second clamp assembly or in an opening movement away therefrom; (d) a hydraulic circuit connected to said actuators capable of selectively causing said closing movement of said pair of clamp arms in unison with each other while said clamp arms are in respective synchronized positions relative to each other and thereafter, automatically in response to a resistance to closing movement of one but not the other of said pair of clamp arms, causing closing movement of said other of said pair of clamp arms so that said pair of clamp arms assume respective unsynchronized positions relative to each other; (e) said hydraulic circuit being capable of selectively causing opening movement of said other of said pair of clamp arms while said pair of clamp arms are in respective unsynchronized positions relative to each other so as to cause attainment by said clamp arms of respective synchronized positions relative to each other and thereafter, automatically in response to said attainment, causing opening movement of said pair of clamp arms in unison with each other while said clamp arms are in respective synchronized positions relative to each other.