Clamping device

The invention provides a clamping device which comprises a vacuum sucker, a sealing washer, press plates, a connector, a pressure switch and a vacuum pump. The sealing washer is arranged on a workpiece placing surface of the vacuum sucker, the press plates are used for fixing a workpiece arranged on the vacuum sucker, the connector is attached on the vacuum sucker, the pressure switch is connected with the connector, and the vacuum pump is connected with the pressure switch. A filter device is arranged between the pressure switch and the vacuum pump. The clamping device further comprises a belt pulley and a motor which are used as energy transferring portions. The combined clamping device has the advantages that sufficient comprehensive sucking force can be generated, so that a part can be firmly fixed onto a fixture, various points of contact portions of the part and the fixture are stressed uniformly, a low-rigidity central area is attached to a working table assuredly after machining, the difficult problem