A relief valve includes: a housing; a plunger movable to each of a closed position and an open position; a differential pressure chamber; a spring member; a piston; and a damping chamber. The plunger includes a first damping passage penetrating the plunger and bringing an area outside the plunger and a through passage into communication. The piston includes a second damping passage penetrating the piston and bringing an area inside the piston and the damping chamber into communication. A communication space connected to each of the first damping passage and the second damping passage is formed between the plunger and the piston.

A break check valve includes a valve body defining a mating surface and a valve inner cavity; a pivot pin positioned inside the valve inner cavity and secured to the valve body, an axis of the pivot pin offset in a radial direction with respect to a longitudinal axis of the valve body; and a valve member positioned within the valve inner cavity and configured to rotate about the pivot pin from an open position to a closed position of the valve, the valve member comprising a plate and an arm extending from the plate, the valve member configured to remain in the open position of the valve as long as a mating surface of a hydrant remains in contact with the mating surface of the valve body and configured to close when the mating surface of the hydrant is separated from the mating surface of the valve body.

A valve for preventing water hammer includes a speed reduction device for reducing a speed at which the valve may be closed. A method of preventing water hammer includes closing a valve at a fire hydrant after extracting water from the fire hydrant, in which the valve comprising a speed reduction device that increases an amount of time needed for closing the valve, and operating the valve to close the valve comprises operating the speed reduction device.

A check valve comprises a valve housing defining a pair of valve openings, a pair of mounting posts arranged on opposed sides of the valve housing, a hinge pin mounted between said mounting posts, a pair of flapper elements pivotably mounted to the one or more hinge pins for rotation relative to the housing between an open position in which they permit fluid flow through the respective valve openings and a closed position in which they prevent fluid flow through the valve openings. A pair of elastically deformable leaf spring stop elements, each of which comprise respective end portions that are mounted to, and extend upwardly from, said mounting posts and a stop portion arching upwardly from, and extending between said end portions, such that each flapper element will engage a respective surface of said stop portion when in the open position.

A valve housing for a check valve comprises a housing body for mounting a pair of flapper elements and a pair of valve openings extending through said valve body. The valve openings are separated by a web which extends from one side of the valve body to an opposed side of the valve body. The valve body and web define sealing surfaces around the valve openings on one face of the valve housing. The web comprises a slot extending into the web from a face thereof on said one face of said valve housing and extending along a length of the web.

An automatic faucet includes a faucet body, an inner core assembly, and a sensor. The inner core assembly includes a valve core, a valve core seat, and a sleeve. The valve core is mounted on the valve core seat. The valve core seat has a cold water hole, a hot water hole, a mixed water hole, and a water outlet. The sleeve is mounted beneath the valve core seat, and has a cold water inlet and a hot water inlet. The sleeve further has a diversion passage communicating with the cold water inlet. The sensor is used to open or close the diversion passage. The sensor includes a sensing module, a solenoid valve, and a buffer rod.

A pressure relief valve includes a valve seat at the outlet, a valve body, and an air dashpot damper. In some embodiments, the valve body is configured to engage the valve seat and move along a central axis relative to the valve seat in response to a pressure at the outlet to regulate a flow of combustible gas through the outlet. In some embodiments, the air dashpot damper includes a tubular member having a closed distal end and an open proximal end, and a piston member received within the tubular member. In some embodiments, the tubular member or the piston member is attached to the valve body, and the piston moves relative to the tubular member along an axis of the tubular member in response to movement of the valve body relative to the valve seat. In some embodiments, the pressure relief valve includes a plurality of the air dashpot dampers.

Provided is a waste gate valve capable of absorbing pulsation following the pulsation of a fluid pressure. In a waste gate valve, a drive gear is rotationally driven by a drive motor, the rotational drive of the drive gear allows a valve shaft engageable with the drive gear to advance or retreat in an axial direction, and the advance or retreat of the valve shaft moves a valve provided at the valve shaft from a valve seat so as to open or close a channel. The waste gate valve includes a main spring for urging the valve in a closure direction. Fluid pressure acting on the valve is transmitted to the drive motor as a load. Furthermore, the waste gate valve includes a damper spring for urging the valve in an open direction.

The present invention relates to a check valve and, more particularly, to a check valve comprising a main disk and a separate auxiliary disk, the main disk making a rapid closing operation, and the auxiliary disk, which has an area smaller than that of the main disk, making a slow closing operation, thereby reducing the velocity of a reverse flow inside a conduit, right before the disks are finally closed, and preventing a slam (a characteristic phenomenon wherein, when the disks are closed with a bang, an instantaneous increase in pressure wave raises the possibility of piping fracture and causes noise and vibration) of the disks and water hammer.

A single one time use valve, based on a Shape Memory Alloy (hereinafter—SMA) actuating component, wherein the valve comprises a nipple component given to shearing and shoving from the instant of its being severed off, in a manner that enables passage of the gas or the liquid from the valve's inlet flow opening to the valve's outlet flow opening wherein the valve is a valve of the normally closed type, or enables stopping of said gas or liquid passage from the inlet flow opening to the outlet flow opening, wherein the valve is a valve of the normally open type, and wherein the valve is characterized by that the inlet flow opening and outlet flow opening are formed substantially on at least one plain, that extends in its direction wherein it is substantially orthogonal to the valve's house assembly lengthwise axis and wherein a physical demarcation exists all the time between the gas or liquid to the valve's SMA made actuating component.