Abstract: A pressure operated shut-off valve for controlling a pneumatic circuit for instance a supply passage of a pneumatic tool, in response to the motive air supply pressure. The valve comprises a valve body that is continuously biased in its closing direction by a spring means and in its opening diection by the motive air supply pressure. If the air pressure drops below a predetermined minimum value the valve is automatically shifted to a closed position by the load of the spring means. A valve body controlled passage means supplies pressure air to the rear end of the valve body as the latter occupies its closed position, thereby making the closed position stable.

Abstract: A spray gun of synthetic resin composition having a hollow barrel with a pistol grip handle including an actuating trigger pivoted from the butt end of the handle, the trigger being mounted to open and close a valve which, in closed position, seals against a valve seat in a passage between the inlet and the outlet of the spray gun. A spring is provided to urge the trigger and valve toward closed position while a latch is positioned on the free end of the trigger to lock the valve member in open position. Hydraulic balance of the valve member is achieved by proper dimensioning and arrangement of the fluid passage, valve member, valve stem and other related parts.

Abstract: A proportional pressure compensating hydraulic control valve having a valve body and a valve spool mounted in the valve body for movement from a neutral or open center position wherein fluid flows through the valve body to an operating position wherein the flow of fluid through the valve is restricted to direct inlet fluid through a flow control orifice to a pressure passage within the valve body, the pressure passage being connected to one of a pair of cylinder passages, the other cylinder passage being connected to a tank passage. The valve spool in an open center mode controlling the flow of fluid to the control orifice and being pressure compensated to maintain a predetermined flow rate through the control orifice, pressure compensation being achieved by imposing inlet and pressure passage pressures selectively to each end of the valve spool so that the valve spool responds to the pressure differential across the control orifice.

Abstract: High-pressure valve provided with internal opening and closing members which are indirectly actuated by a handwheel and a servo-control system based on the balancing effect generated by the same pressure of compressed air or gas or the like to be dispensed so as to obtain a very sensitive operation, the assembly being particularly suitable for compressed air or gas bottles or the like.

Abstract: In one embodiment, a valve body contains a flexible valve sleeve between a fluid inlet and a fluid outlet, and an annular chamber around the sleeve connects with the inlet so that fluid pressure in the chamber normally compresses the sleeve to a closed position. A manually operated pilot valve reduces pressure in the chamber so that the sleeve is expanded by fluid pressure from the inlet to open the valve.In another embodiment, a valve body contains a flexible diaphragm which normally closes an inlet valve port and defines a pressure chamber isolated from a fluid outlet. A manually operated pilot valve reduces pressure in the chamber so that the diaphragm is unseated from the inlet port by fluid pressure from the inlet to open the valve.

Abstract: A valve construction for controlling the flow of a fluid therethrough and including a restrictor member that is located in a control chamber and that communicates with the control pilot valve and an interior chamber having access to a pressure responsive diaphragm, the restrictor member providing for sufficient flow of fluid to the interior chamber in relatively large valve sizes to enable the diaphragm to open or close the valve at a reasonable valve closing rate, the closing of the valve being slow enough to prevent the occurrence of water hammer in the system.

Abstract: The present invention deals with a bag diaphragm comprising one or more flattened extremely flexible bags assembled together, to be mounted between rigid plates at a variable mean distance and to be inflated in operation by a variable pressure difference, and with an air damper operated by means of a bag diaphragm as mentioned above, this air damper being suitable for air conditioning plants, in constant flow, or constant variable flow, or mixing appliances, in fresh air and return air ducts, where an air flow is to be controlled, the operation of the air damper being possible without any electrical or pneumatic energy supply system, due to the particular characteristics of the aforesaid bag diaphragm and particular design of the damper.