Ring disc nozzle check valve 100 allows fluid flow in one direction and can act as a relief valve and comprises valve body 1 which defines valve body fluid passageways 20,22 therethrough; primary seat 2 disposed in valve body fluid passageways 20,22 proximate fluid inlet 30; primary disc 4 disposed in valve body fluid passageways 20,22 proximate fluid inlet 30 and in communication with primary seat 2; secondary disc 5 nested within valve body fluid passageways 20,22, where secondary disc 5 defines secondary seat 3 at a peripheral edge of primary disc 4; diffuser 8 disposed in the valve body fluid passageway 20 proximate fluid outlets 32a,32b; primary spring 10 disposed in valve body fluid passageways 20,22 and in communication with diffuser 8 and primary disc 4, where primary spring 10 is adapted to urge primary disc 4 to a closed position; primary shaft 6 disposed within valve body fluid passageway 22 intermediate diffuser 8 and secondary disc 5, where primary shaft 6 is in communication with diffuser 8 and adapted to support and guide primary disc 4 and allow fluid flow through primary shaft 6; secondary shaft 7 disposed within valve body fluid passageway 22 and configured to support and guide secondary disc 5; secondary spring 11 disposed intermediate secondary shaft 7 and secondary disc 5 and configured to urge secondary disc 5 to a closed position; inner body valve seat support 9, which may act as a retention ring, disposed proximate to fluid outlets 32a,32b and configured to do not disrupt fluid flow within ring disc nozzle check valve 100 as the fluid passes over primary disc 4 and/or secondary disc 5; and one or more fasteners 12 configured to secure retention ring 9 to valve body 1.

An expansion tank includes a tank body mounted inside a housing forming a sump, where the tank body defines an internal expansion volume. A fluid inlet tube on the tank body has an upper end open to the sump and a lower end open to the internal expansion volume. A single 2-way check valve is located at the lower end of the tube, and fluid enters the expansion volume when the pressure in the sump exceeds the pressure in the expansion volume by a first predetermined amount, and fluid exits the expansion volume to the sump when the pressure in the expansion volume exceeds the pressure in the sump by a second predetermined amount. The check valve may be a combination duckbill valve and umbrella valve. The tank body may include a cover on which the inlet tube is formed.

A check valve including a valve housing defining a pair of valve openings; a pair of flappers pivotably mounted 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; and a stop element arranged such that the flappers will contact the stop element in their open positions. Each flapper includes a primary flapper element pivotally mounted to a hinge pin that extends across the valve, and a secondary flapper element. The primary flapper element further includes at least one flapper opening formed therethrough. The secondary flapper element is pivotally mounted such that it may rotate relative to the primary flapper element for opening and closing the at least one flapper opening in the primary flapper element.

A hydraulic fluid expansion tank is located inside a housing of a drive device and includes an upper check valve and a lower check valve in communication with a sump located within the drive device and an internal volume of the expansion tank. The tank may also include a vent opening in communication with a vent of the drive device that is in communication with atmospheric pressure.

A fluid control valve includes a housing body, a valve member, and a cap. The housing body includes a pipe part and a valve housing part. The valve housing part includes a valve opening, a pair of flat surfaces and an open end. In addition, the valve housing part houses the valve member configured to open and close the valve opening. The valve housing part has a central axis oriented perpendicular to a central axis of the pipe part. The cap closes the open end of the valve housing part. The flat surfaces are formed on opposite sides of a plane including the central axis of the valve housing part and the central axis of the pipe part. Each of the flat surfaces extend perpendicularly to the central axis of the valve housing.

A flapper assembly for an aspirator system includes a flapper plate and a valve assembly. The flapper plate defines a first plurality of apertures. The valve assembly includes a first valve plate disposed over the first plurality of apertures and a first pressure relief assembly arranged to move the first valve plate relative to the flapper plate.

A ball check valve controls the flow of fluid with a sphere. A body has a fluid path and a recess for receiving the sphere in alignment with the fluid path. The sphere has a retainer which secures a ball check within it. When the valve is in a Run position and the rate of fluid flow increases excessively, the ball check seats in a narrow opening of the sphere, thus restricting the flow of fluid.

A check valve including a valve housing defining a pair of valve openings; a pair of flappers pivotably mounted 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; and a stop element arranged such that the flappers will contact the stop element in their open positions. Each flapper includes a primary flapper element pivotally mounted to a hinge pin that extends across the valve, and a secondary flapper element. The primary flapper element further includes at least one flapper opening formed therethrough. The secondary flapper element is pivotally mounted such that it may rotate relative to the primary flapper element for opening and closing the at least one flapper opening in the primary flapper element.

The invention discloses a tilting disc check valve, which includes a left valve body (1), a right valve body (2), a large valve plate (3), a small valve plate (4) and a diaphragm control group (5), wherein the left valve body (1) and the right valve body (2) are butted into a whole through oblique openings; the oblique openings are inclined in a manner that upper parts are inclined towards the right valve body (2); the diaphragm control group (5) is arranged on the left valve body (1); the large valve plate (3) is arranged along the oblique openings; the large valve plate (3) is positioned in a valve cavity formed by the left valve body (1) and the right valve body (2); the large valve plate (3) is suspended on shaft holes of the left valve body (3) through valve shafts (6); the small valve plate (4) is connected with the diaphragm control group (5); and the small valve plate (4) is mounted at a slow closing valve port of the large valve plate (3) through a small valve plate pin shaft (7). According to the tilting disc check valve, a two-stage valve closing process where the large valve plate is quickly closed and the small valve plate at a drain hole of the large valve plate is slowly closed within adjustable time can be implemented, and the aims of reducing backflow of a water body and eliminating pump starting and stopping water hammer are fulfilled.

A valve (4, 4) for a fuel system for a combustion engine: A ball retainer (26) is provided with a cavity (28) to accommodate a ball (22). The ball (22) has a first seal surface (30) to cooperate with and abut sealingly against a seat (32). The ball retainer (26) has a secondary seal surface (34) to cooperate with and abut sealingly against the seat (32) when the ball (22) is not in the ball retainer (26). Also, a method for controlling a fuel system for a combustion engine.