Detecting presence of workpiece at manipulating suction plate

摘要

The workpiece detection method involves manipulating objects by a suction plate (1) which is attached to a hollow body (20) with an internal pressure (P1). Suction is applied from pipework (3) and a bellows (23) is located inside the hollow body (20). The lid of the bellows (25) operates a pivoted flap valve (34). The bottom of the bellows at pressure (P3) is connected (28) to the suction source at a point of pressure (P2). If suction is applied to the plate (1) and the intended object is not correctly aligned to cover the plate the pressure outside the bellows (23) being (P1) will be greater than that inside (P3). This will cause the bellows to retract and the flap valve (34) to close the source of suction (3).