Patent ID: 7007795

Claim:
A workpiece transport conveyor ( 1 , 38 , 50 ) comprising a workpiece transport support ( 4 , 41 , 52 ) having a workpiece transport surface ( 16 , 43 , 44 ) for carrying and transporting a workpiece, a drive ( 34 ) with a drive transmission ( 12 , 45 , 57 ) for moving the workpiece transport support ( 4 , 41 , 45 ) in a transport direction, a traction device ( 18 ) for transferring drive energy between said drive ( 34 ) and workpiece transport support ( 4 , 41 , 52 ) for moving the workpiece transport support ( 4 , 41 , 45 ) in the transport direction, said traction device ( 18 ) having an input element ( 21 , 46 , 55 , 54 ) and an output element ( 19 , 44 , 53 ), said traction device ( 18 ) having a contact free hysteresis coupling ( 22 ) for coupling the input and output element without physical contact therebetween, said hysteresis coupling ( 22 ) including a magnetic coupling element ( 19 , 24 , 31 , 44 , 53 ) and a hysteresis coupling element ( 32 , 29 , 48 , 58 ), one of said coupling elements being coupled to said input element ( 21 , 46 , 55 , 54 ) and the other of said coupling elements being coupled to said output element ( 19 , 44 , 53 ), said hysteresis coupling being operable for coupling said input element to said output element for transmitting drive energy from said input element to said output element and said workpiece support for causing unimpeded movement of said workpiece support in said transport direction, and said hysteresis coupling being uncouplable in response to movement of said workpiece transport support being interrupted for permitting contact free relative movement of said input element to said output element that interrupts the transmittal of drive energy from said input element to said output element and said workpiece transport support.