The invention relates to a pressure-controlled shut-off valve (1) for temporarily interrupting the air supply to a fuel cell stack in a fuel cell system, comprising a valve piston (3) which can be moved back and forth in a cylindrical housing bore (2) and which is biased in the direction of a seal seat (5) by the spring force of a spring (4), wherein a connection between an air inlet channel (6) and an air outlet channel (7) is produced or interrupted depending on the axial position of the valve piston (3). According to the invention, the valve piston (3) delimits a spring chamber (8), which receives the spring (4) and to which ambient pressure is applied, on one side and a control chamber (9), which is connected to the air inlet channel (7), on the other side within the housing bore (2). The invention additionally relates to a fuel cell system comprising a shut-off valve (1) according to the invention.

Systems and methods described herein provide for pressure relief valve detection and monitoring. A valve assembly includes a striker and an indicator assembly separated by a diaphragm. The diaphragm may be elastically or permanently deformable. The striker may be connected to a relieve valve disk that releases in response to high fluid pressure at the valve. Movement of the striker may be detected by contact with the diaphragm or by sensors near the diaphragm, which may trigger the indicator assembly to provide an external indication of a valve opening.

Systems and methods described herein provide for pressure relief valve detection and monitoring. A valve assembly includes a striker and an indicator assembly separated by a diaphragm. The diaphragm may be elastically or permanently deformable. The striker may be connected to a relieve valve disk that releases in response to high fluid pressure at the valve. Movement of the striker may be detected by contact with the diaphragm or by sensors near the diaphragm, which may trigger the indicator assembly to provide an external indication of a valve opening.

A damped check valve having multi-pressure operation is provided. The check valve includes a liner with a poppet movable within the liner. The liner defines a flow passage aligned along a longitudinal axis defined by the liner. A biasing element is operably coupled between the poppet and the liner to bias a first flow face of the poppet against an annular seat. The first flow face is configured such that a first fluid pressure is required to move the poppet from the closed position to an open position wherein the poppet is unseated from the annular seat and a second fluid pressure is required to hold the poppet in the open position, the second pressure being less than the first pressure. There is a sufficient diametrical clearance between the poppet and the liner which allows for flow control at pressures which are less than the initial opening pressure.

A safety valve is configured for use at temperatures at or above 760° C. (1400° F.). The safety valve includes a closure assembly that can create a self-energizing, metal-to-metal seal. In one implementation, this closure assembly includes a disc with an arcuate finger that circumscribes an axis of fluid flow through a seat. The arcuate finger may extend inwardly toward this axis and downwardly toward the seat. This geometry permits the finger to flex in response to pressure of fluid that impinges on the downstream side of the disc, such flexure causing a first sealing surface on the disc to more forcefully contact a second sealing surface on a seat.

A method for assembling a valve is disclosed. The valve includes a first fluid port, a second fluid port, a fluid path providing fluid communication therebetween, a moveable member, a biasing member and a pressure compensation membrane. The method includes the steps of providing a base member comprising an abutment for receiving a first of the biasing member and the pressure compensation membrane; assembling the biasing member and the pressure compensation membrane with the base member; and affixing a fixing member to the base member to retain the biasing member and the pressure compensation membrane between the fixing member and the abutment.

A method for assembling a valve is disclosed. The valve includes a first fluid port, a second fluid port, a fluid path providing fluid communication therebetween, a moveable member, a biasing member and a pressure compensation membrane. The method includes the steps of providing a base member comprising an abutment for receiving a first of the biasing member and the pressure compensation membrane; assembling the biasing member and the pressure compensation membrane with the base member; and affixing a fixing member to the base member to retain the biasing member and the pressure compensation membrane between the fixing member and the abutment.

An enclosure containing an inerting gas and at least one liquid to be discharged. This enclosure comprises at least one orifice positioned in its lower part and a liquid discharging system positioned at the orifice. This liquid discharging system is configured to take up a closed state and an open state in which the system allows the liquid to flow towards the outside of the enclosure and includes at least one element that is elastically deformable depending on the pressure inside the enclosure and, depending on its deformation, controls the open or closed state of the liquid discharging system. This solution makes it possible to achieve simple and automatic regulation of the volume of the liquid in the enclosure, without a sensor. An aircraft including at least one such enclosure is also provided.

A system for modulating delivery of a fluid medium includes an injector for injecting the fluid medium during an injection cycle, a delivery catheter including a conduit for delivering the fluid medium, a manifold disposed in a fluid medium flow path between the injector and the delivery catheter, and a pulsatile generator. The pulsatile generator is configured to apply a pulsatile force to the fluid medium defined by a plurality of duty cycles during the injection cycle, each of the duty cycles including a first pressure level and a second pressure level that is lower than the first pressure level.

A capacity control valve includes a valve housing provided with a Ps port through which a suction fluid at a suction pressure passes and a Pc port through which a control fluid at a control pressure passes; a valve body configured to close and open a communication between the Pc port and the Ps port by a driving force of a solenoid; and a pressure sensitive body that applies a biasing force to the valve body according to a surrounding fluid pressure. An accommodation chamber in which a rear side portion of the valve body is accommodated is provided with a supply passage to which suction fluid is supplied.