Pressure detecting device

摘要

A pressure detecting device for detecting air pressure by means of a pressure receiving member which is energized by a coil spring, wherein a seal is provided between the side wall of the detector housing at the pressure detecting port side and the pressure receiving member as well as between the other side wall of the housing at the discharge port side and the pressure receiving member and further sealing area at the discharge port side is larger than that at the pressure detecting port side. As a preferred application of the pressure detecting device a control system for a press machine is constructed such that operation and stop of the press machine are controlled by way of controlling supply and discharge of pressurized air to and from the press machine with the aid of a double valve and the pressure detecting device. As another preferred application of the pressure detecting device a stroke ends detecting system for a pneumatic cylinder is constructed such that both pressure chambers in the pneumatic cylinder divided by the piston are communicated with the pressure detecting ports of the pressure detecting devices.