Workpiece detection device for cyclical machines

In a cyclically operating machine for performing an operation on successive workpieces including ejection means for ejecting a workpiece after each operating cycle and control means associated with the machine drive means for initiating each operation cycle, a detection device interlocked with the control means for sensing the event of a workpiece having been ejected to enable initiation of the next machine operating cycle, said detection device comprising a chute adapted to be disposed adjacent to machine for receiving an ejected workpiece, said chute including a pivotally mounted base having an upstream portion and a downstream portion wherein said downstream portion is moveable between raised and lowered positions, biasing means for normally urging said base toward said raised position, said base being moveable to said lowered position in response to the weight of an ejected workpiece, the improvement comprising sensing means for sensing said pivotally mounted base when in said lowered position indicative of the event of an ejected workpiece and means for adjusting the force exerted by the biasing means on said pivotally mounted base to accommodate workpieces of various weights.