Abstract: A reciprocating body 12 is reciprocably housed in a cylinder body 6, and a pressure rod 20 is reciprocably attached to this reciprocating body 12. A pressure end 20a of the pressure rod 20 protrudes from the cylinder body 12 toward the outside. By the reciprocating body 12 and diaphragms 17 to 19, an advance pressure chamber 27 and a weight offset pressure chamber 29 are partitioned and formed in the cylinder body 6. After the pressure end 20a is disposed vertically downwardly, the weight offset pressure chamber 29 is filled with compressed fluid, whereby self weight of the reciprocating body 12 and the pressure rod 20 is offset. Then, the compressed fluid is supplied to the advance pressure chamber 27, and an object to be pressurized W is pressurized through the pressure rod 20.

Abstract: A reciprocating body 12 is reciprocably housed in a cylinder body 6, and a pressure rod 20 is reciprocably attached to this reciprocating body 12. A pressure end 20a of the pressure rod 20 protrudes from the cylinder body 12 toward the outside. By the reciprocating body 12 and diaphragms 17 to 19, an advance pressure chamber 27 and a weight offset pressure chamber 29 are partitioned and formed in the cylinder body 6. After the pressure end 20a is disposed vertically downwardly, the weight offset pressure chamber 29 is filled with compressed fluid, whereby self weight of the reciprocating body 12 and the pressure rod 20 is offset. Then, the compressed fluid is supplied to the advance pressure chamber 27, and an object to be pressurized W is pressurized through the pressure rod 20.

Abstract: A pneumatically-operated valve in which a valve actuator is formed of two separate parts: a driving member having a plurality of sealed pistons fixed to a piston rod in series to be operated by air pressure, and a valve operating member which comes into contact with a clean fluid and which does not have any soft substances such as O-rings which are likely to be impaired by ultrasonic cleaning. The valve facilitates the cleaning of the members during the process of manufacture and furthermore can provide a great deal of output for its size without contaminating the clean fluid during use.

Abstract: A pilot operated directional control valve having a diaphragm held between a passage block which has a feeding port, at least one loading port and at least one discharge port, and an opposed control block which has pilot pressure passages. The ports of the passage block open into the end face of the passage block adjacent to the control block through respective fluid passages. The pilot pressure is exerted on the diaphragm by the pilot pressure passages to control the fluid connection between the ports of the passage block. The fluid passages are located in a concentric arrangement.The diaphragm has a center valve portion with an annular valve portion therearound. The two valve portions can be independently controlled by the pilot pressure acting thereon to control the fluid connection between the two adjacent fluid passages.

Abstract: A pneumatically-operated valve in which a valve actuator is formed of two separate parts: a driving member having a plurality of sealed pistons fixed to a piston rod in series to be operated by air pressure, and a valve operating member which comes into contact with a clean fluid and which does not have any soft substances such as O-rings which are likely to be impaired by ultrasonic cleaning. The valve facilitates the cleaning of the members during the process of manufacture and furthermore can provide a great deal of output for its size without contaminating the clean fluid during use.

Abstract: A pilot operated directional control valve having a diaphragm held between a passage block which has a feeding port, at least one loading port and at least one discharge port, and an opposed control block which has pilot pressure passages. The ports of the passage block open into the end face of the passage block adjacent to the control block through respective fluid passages. The pilot pressure is exerted on the diaphragm by the pilot pressure passages to control the fluid connection between the ports of the passage block. The fluid passages are located in a concentric arrangement. The diaphragm has a center valve portion with an annular valve portion therearound. The two valve portions can be independently controlled by the pilot pressure acting thereon to control the fluid connection between the two adjacent fluid passages.

Abstract: A fluid directional control valve having a valve housing with valve chamber therein, an elastic seal ring for sealing the valve chamber, valve ports provided in the housing and connected to the valve chamber, a valve arm having valve bodies and swingably supported in and by the seal ring, and an actuator for actuating the valve arm, so that the valve bodies selectively open and close the valve ports in order to control the fluid connection between the valve ports, in accordance with the swing movement of the valve arm.

Abstract: A pilot operated directional control valve having a diaphragm held between a passage block which has a feeding port, at least one loading port and at least one discharge port, and an opposed control block which has pilot pressure passages. The ports of the passage block open into the end face of the passage block adjacent to the control block through respective fluid passages. The pilot pressure is exerted on the diaphragm by the pilot pressure passages to control the fluid connection between the ports of the passage block. The fluid passages are located in a concentric arrangement. The diaphragm has a center valve portion with an annular valve portion therearound. The two valve portions can be independently controlled by the pilot pressure acting thereon to control the fluid connection between the two adjacent fluid passages.

Abstract: An improved pneumatically operated valve for controlling supply of fluid to a certain apparatus adapted to be operated for an intended purpose using the thus supplied fluid. The valve includes a valve portion on the piston rod and a flow passage of fluid is normally kept in the opened state or in the closed state by means of a the valve portion under the effect of force exerted on the piston in a predetermined direction. When any abnormal fluctuation of pressure of fluid is detected, pressurized air is introduced into the interior on the casing so ast to exert its pressure on the pistion against the aforesaid force of the piston, whereby the flow passage is shifted from the opened state to the closed state or from the closed state to the opened state.