A fault-accommodating flow scheduling valve has a first inlet, outlet, and orifice therebetween. The valve has a shuttle valve member on the orifice inlet side, a primary valve member on the orifice outlet side, a compression-loaded primary spring, and first and second compression-loaded balance springs. Below a threshold differential pressure, the primary valve member engages with the outlet-side sealing face to close the valve while the shuttle valve member is spaced from the inlet-side sealing face, and on failure of the primary spring, the primary valve member moves from the outlet-side sealing face but the shuttle valve member closes the valve. Above the threshold differential pressure, the primary valve member opens the valve while the shuttle valve member remains spaced, and on failure of the primary spring, the primary valve member moves further from the outlet-side sealing face but the shuttle valve member closes the valve.

The present invention discloses a regulable pressure relief valve for a draft beer fresh-keeping keg, comprising a valve body housing, a first compression spring, a mushroom-shaped ejector rod, a second compression spring and a pressure exerting block. Said first compression spring, ejector rod, second compression spring and pressure exerting block are coaxially distributed; the ejector rod comprises a retractable rod and a mushroom head; the first compression spring is put on the retractable rod and the two ends of the first compression spring is stressed between the bottom of the mushroom head and the valve body housing; the two ends of the second compression spring is stressed between the top of the mushroom head and the pressure exerting block; a pressure regulation at the top of the retractable rod is realized by exerting a pressure on the pressure exerting block and thus realize the pressure regulation function.

The valve for pressure compensation and/or for emergency venting of a container, preferably of a housing of a vehicle battery, has a housing (6) with an inlet (6a) that is closable by at least one valve element (23) subjected to a closing force in a first position. The housing (6) is at least partially gas-permeable and preferably water-tight, and has at least one outlet (26) which is located behind the valve element (23) when the valve element (23) assumes its first position. So that in case of a malfunction even larger quantities of gas can be guided to the exterior through the valve, is the valve element for an increased pressure surpassing the closing force at the inlet (6a) is adjustable in the direction toward a second position against the closing force, in which the valve element (23) at least partially opens the outlet (26) such that the outlet (26) is directly connected in flow communication with the inlet (6a).

A pressure relief valve is disclosed with a first stage valve that is in series with a second stage valve, with an enclosed cavity between the first stage valve and the second stage valve. The first stage valve relieves pressure from an enclosure into the enclosed cavity between the stages, when the pressure is above a cracking pressure of the first stage valve. The second stage relieves pressure from the enclosed cavity when the pressure is above the cracking pressure of the second stage valve.

A backflow prevention device includes a piston received in a device passage between an inlet port and outlet port. A relief port can fluidly communicate with a middle segment of the device passage. The piston is movable between a normal flow position in which the piston blocks fluid communication between the relief port and the middle segment of the device passage and a backflow position in which the piston allows fluid communication between the relief port and the middle segment of the device passage. The piston can move to the normal position in response to normal flow through the device passage from the inlet port toward the outlet port and configured to move to the backflow position in response to greater pressure in the middle segment than in the inlet port.

A pressure relief valve is disclosed with a first stage valve that is in series with a second stage valve, with an enclosed cavity between the first stage valve and the second stage valve. The first stage valve relieves pressure from an enclosure into the enclosed cavity between the stages, when the pressure is above a cracking pressure of the first stage valve. The second stage relieves pressure from the enclosed cavity when the pressure is above the cracking pressure of the second stage valve.

A fluid control valve having extremely high responsiveness not only when a pressure of a working fluid of a first flow path is high but also when the pressure of the working fluid of the first flow path is low includes: a valve seat; a valve body contacting and separating from the valve seat; a first biasing member biasing the valve body in a valve closing direction; and a second biasing member having a spring force lower than that of the first biasing member, wherein the valve body is axially divided into a base portion biased by the first biasing member and an opening and closing portion contacting and separating from the valve seat, and the second biasing member is disposed so that the base portion and the opening and closing portion are axially separable from each other.

A spherical pump valve. The valve includes a valve cage, a spring, a valve member, a valve seat, and a locking ring. The valve cage has a groove holding the spring and threads. The valve member has a stem and a trench holding the spring. The valve seat has a seating surface, threads that match the valve cage threads and upon threaded engagement secure the valve seat to the valve cage, and a channel. The locking ring is installed in the channel and secures the valve cage to the valve seat. The spring has a rate matched to the weight of the valve member and to the flow area of the valve seat. The stem guides the valve member as the stem travels through a center hole of the valve cage. Also disclosed is a pump including the valve.

A hydraulic control apparatus includes an output-side oil passage into which oil from a first oil passage and oil from a second oil passage flow, and a pressure regulating check valve regulating a hydraulic pressure in the second oil passage. The pressure regulating check valve includes first and second elastic portions housed in a spool hole between a valve body and a bottom of the spool hole. A natural length of the second elastic portion is shorter than a distance between the valve body and the bottom when the valve body closes an inflow hole. The second elastic portion applies an elastic force to the valve body in a state in which the valve body opens the inflow hole.

An example counterbalance valve includes: a poppet configured to be subjected to a fluid force by fluid received at a first port, and a fluid force by a pilot pressure fluid signal received at a pilot port; a first setting spring disposed in a first chamber and applying a first biasing force on the poppet; and a second setting spring disposed in a second chamber and applying a second biasing force on the poppet, wherein the first chamber and the second chamber are vented to an external environment of the counterbalance valve, wherein the second setting spring is in parallel with the first setting spring such that an equivalent biasing force acting on the poppet in the distal direction comprises a sum of the first biasing force and the second biasing force.