| 摘要 |
The invention concerns a vacuum lifter to transport loads with an adhesi on surface, comprising at least one suction head suspended from a hoist, said suction comprising at least one annular seal projecting from its suction side, the vacuum chamber(s) enclosed by the annular seal(s) communicating with a vacuum source, a valve furthermo re being provided which can be switched between a suction position wherein the vacuum source communicates with the pressure chamber or vacuum chambers and a venting position wherein the communication with the vacuum source is interrupted and the vacu um cham- bet(s) is (are) vented or fed with compressed air. To assure venting or compressed-air supply immediately upon deposition of the load, the hoist is connected by a fitting 55 to the suction plate 5, said fitting being guided in vertically displaceable manner between two end positions, a sensor or a limit switch 59 being provided to detect the lower end position of the fitting 55 and so cooperating with a control means that following lowering o f the fitting 55, the valve 20 shall be switched into the venting position if previously havin g been in the suction position.
|
