A check valve can include a pressure actuator or an electromagnetic actuator. The check valve includes a valve inlet, a valve outlet, and flap disposed between the valve inlet and the valve outlet. The check valve has an open state and a closed state. The pressure actuator in fluid communication with the valve inlet. The check valve has an open state and a closed state. The check valve is configured to allow an input gas to flow from the valve inlet to the valve outlet when the check valve is in the open state. The check valve is configured to preclude the input gas from flowing from the valve inlet to the valve outlet when the check valve is in the closed state. Upon actuation of the pressure actuator or the electromagnetic actuator, the flap moves away from the valve inlet to allow the inlet gas to move from the valve inlet to the valve outlet.

A check valve can include a pressure actuator or an electromagnetic actuator. The check valve includes a valve inlet, a valve outlet, and flap disposed between the valve inlet and the valve outlet. The check valve has an open state and a closed state. The pressure actuator in fluid communication with the valve inlet. The check valve has an open state and a closed state. The check valve is configured to allow an input gas to flow from the valve inlet to the valve outlet when the check valve is in the open state. The check valve is configured to preclude the input gas from flowing from the valve inlet to the valve outlet when the check valve is in the closed state. Upon actuation of the pressure actuator or the electromagnetic actuator, the flap moves away from the valve inlet to allow the inlet gas to move from the valve inlet to the valve outlet.

A stop pin for a check valve includes a first end and a second end and extending from the first end to the second end in a longitudinal direction along a longitudinal axis. The stop pin also includes at least one slot therein extending in said longitudinal direction, said at least one slot defining a respective at least one flexible, cantilevered tongue having a free end and a connected end connected to said stop pin.

A liquid sampler for use in sampling the liquid in a well. The sampler has a tube for containing the sample and an inlet at the bottom and an outlet at the top. An inlet check valve is located at the inlet which has a door configured autonomously to move between open and closed configurations in response to fluid flow through the inlet. In the open configuration, the door is aligned with the axis of the tube to allow fluid to flow into the tube through the inlet from below, and in the closed configuration, the door is positioned transverse to the axis of the tube to block fluid flow from the tube out through the inlet thereby retaining fluid within the tube as the sampler is raised up.

A passive explosion isolation valve (10) is provided that comprises vertically-oriented gate members (40, 42) configured to close automatically in response to an energetic event occurring downstream of the valve. The valve (10) may be optionally equipped with a valve seat cleaning assembly (46) configured to removed accumulated particulate material away from the area of the valve seat (48) and/or one or more latch assemblies (44) configured to secure the gate members (40, 42) in the closed position following closure of the valve (10) in response to an energetic event.

A fluid circulation assembly for a dishwasher appliance includes a pump, a diverter, and a valve. The diverter includes an inlet and a plurality of outlet ports. The inlet of the diverter is in fluid communication with the pump for receiving fluid from the pump. The valve is in fluid communication with the diverter via one or more of the plurality of outlet ports. The valve includes a housing, a dual check valve assembly mounted in the housing and a plurality of conduits. The dual check valve assembly selectively directs fluid from the diverter to one or more of the plurality of conduits.

A check valve comprises a valve housing defining at least one valve opening, and at least one flapper pivotably mounted for rotation relative to the valve housing between an open position in which it permits fluid flow through the respective valve opening and a closed position in which it prevents fluid flow through the valve opening. The valve housing comprises a hinge body which comprising a hinge groove extending in a straight line in a longitudinal direction therethrough from a first end to a second end. The hinge groove has, in a plane transverse to the longitudinal direction, an arcuate profile. The at least one flapper comprises a hinge tongue formed along a proximal edge thereof. The hinge tongue extends in a straight line in a longitudinal direction along the proximal edge of the flapper from a first end to a second end.

A fluid circulation assembly for a dishwasher appliance includes a pump, a diverter, and a valve. The diverter includes an inlet and a plurality of outlet ports. The inlet of the diverter is in fluid communication with the pump for receiving fluid from the pump. The valve is in fluid communication with the diverter via one or more of the plurality of outlet ports. The valve includes a housing, a dual check valve assembly mounted in the housing and a plurality of conduits. The dual check valve assembly selectively directs fluid from the diverter to one or more of the plurality of conduits.

A flapper element for a check valve comprises at least one mounting lug configured to receive a shaft for rotation relative thereto and having a row of teeth for engaging complementary teeth on a mounting lug of a similar flapper element. The complementary teeth tie the rotation of the two flapper elements.

A prosthetic heart valve having a pair of cooperating leaflets mounted in a valve body to alternate between an open position where the flow of blood in a downstream direction is permitted and a closed position where the flow of blood in the reverse direction is counteracted. Pivot member sets at diametrically opposite sides of each leaflet guide the leaflets moving between the open and closed positions, each set including an ear or a recess cooperating with an associated cavity or knob of an interior surface of the valve body. Each ear or recess bounds at least one leaflet passageway through that ear or recess and located spaced from upstream and downstream ends of the ear for allowing flow through that ear and the associated cavity, or through that recess, when the leaflets are in the closed positions.