A first passage communicating with a compressed air supply port, a sixth passage communicating with a vacuum port, and an eighth passage communicating with an air discharge port for a solenoid-operated valve are arranged in parallel respectively. Further, a pressure fluid-supplying solenoid-operated valve, a vacuum-breaking solenoid-operated valve, a flow rate-adjusting screw, a suction filter, and a vacuum pressure switch are successively arranged in series in a main body section.