A backwater valve has a valve body, and a valve member pivotally movable about a pivot axis between an open position away from the valve body and a closed position covering the valve body. A control linkage is provided with at least one of a float or a counterweight in communication with the valve member via the control linkage to modify operation of the valve member.

The present invention allows for a combination valve in a hydronic HVAC system that functions as an isolation valve; a check valve; and as a device for measuring fluid parameters, such as flow rate, pressure, and/or temperature, and also allows for the isolation valve to be configured in the field to be mounted either in a straight 180? or an angled 90? orientation, as well as at an intermediate angle. The new combination of isolation valve, check valve, with embedded sensors for flow rate, pressure, and/or temperature measurement provides a more compact product envelope that achieves space savings, e.g., by eliminating the need for separate components in an HVAC system, such as separate isolation valves, check valves, flow meters, pressure gages, and/or thermometers.

A combination control and check valve assembly for a wet piping system includes a control valve in the form of a ball valve and a one-way check valve mounted within the flow pathway of the ball valve. A valve actuation assembly is mounted to the valve assembly to selectively rotate the ball valve between the open and closed positions thereof. The valve actuation assembly is mounted to a first side of the valve assembly and rotationally fixed to the ball, whereby rotation of the valve actuation assembly rotates the ball between the open and closed positions. A side opening is formed in a second side of the valve assembly that is angularly spaced from the first side. The side opening is positioned to align with the fluid flow pathway of the ball valve in the closed position thereof to provide access to the check valve.

A hinge pin for a check valve includes a shaft, a first end of the shaft, a second end of the shaft opposite the first end, and a first connection element on the shaft between the first end and the second end. The first connection element lockably connects to a valve disk assembly, the first end having a second connection element to connect to an oil-cushion arm, the second end having a third connection element to connect to a counterweight arm, the shaft being composed of maraging steel.

A spring return check valve that has a body forming a fluid flow path therethrough, a cover that closes an opening in the body and including a cavity therein facing the fluid flow path, a disc that rotates from a first position closing the fluid flow path and a second position fully opening the fluid flow path and a spring connected between the cover and the disc and including extensions integrally extending from each end of the spring to cause the spring to buckle into the cavity when the disc rotates to the second position.

A spring return check valve that has a body forming a fluid flow path therethrough, a cover that closes an opening in the body and including a cavity therein facing the fluid flow path, a disc that rotates from a first position closing the fluid flow path and a second position fully opening the fluid flow path and a spring connected between the cover and the disc and including extensions integrally extending from each end of the spring to cause the spring to buckle into the cavity when the disc rotates to the second position.

Disclosed is a reduced-pressure type backflow preventer comprising a valve body (1), two check valves (2) of the same structure and a drain valve:(3) wherein a cavity is formed body, and a valve wall of the valve body is provided With a water inlet, a water outlet, and a drain opening; the two check valves are both fixedly mounted inside the valve body supporting member (4), and are positioned at the water inlet and the water outlet, respectively; the drain valve is mounted outside the valve body, and is positioned at the drain opening; the check valve comprises a valve seat (201), a valve clack (202), a rocking bar (203), and a twin torsional spring (204); one side of the valve clack is hinged to an upper end of the valve seat, and the other side is provided with a roller (205); the rocking bar is connected to a lower end of the valve seat via a pin (206); the roller abuts against the rocking bar and slides on the rocking bar; the twin torsional spring is sheathed over the pin; and a spring force of the twin torsional spring acts on the rocking bar to maintain the valve clack in a normally closed state, and an external force is used to cause the roller on the valve clack to roll on the rocking bar so as to open the valve clack. The preventer provides a better flow preventing effect by virtue of the structure of the twin torsional spring and the rocking bar of the check valve.

Embodiments include a check valve that comprises a valve body defining an inlet port and an outlet port; a disc disposed within the valve body, wherein the disc is coupled to a pivot shaft and the pivot shaft is coupled to the valve body; a lever arm coupled to the disc, wherein when the disc rotates the lever arm rotates; an actuator shaft couple to a motor, and a first interference element coupled to the actuator shaft, wherein the lever arm contacts the first interference element when the disc is in a maximum open position; wherein when the motor rotates the actuator shaft moves longitudinally along its axis to move the first interference element thereby changing the maximum open position. Other embodiments are also included herein.

A device for holding a flap of a non-return valve in a closed position, which is configured to carry out hydraulic testing of a device or apparatus, includes a body which takes the form of a caliper with two arms that are articulated relative to each other, at a first of the two opposite ends thereof, about a first axis, in that it includes a holder articulated about the first axis and in that the two arms each has, at the second end thereof, a pad pivoting about axes that are parallel to the first axis.

An ejector for vaporized fuel gas recirculation devices is provided. The ejector for vaporized fuel gas recirculation devices reduces the number of elements equipped in a vehicle and an ejector mounting angle is adjusted to be suitable for a layout environment of the vehicle. Accordingly, a mounting cavity of the vehicle is more efficiently designed. When an intake pressure of an intake manifold is reduced a base component is moved in a direction toward a first nozzle component, and a region of the base component except an aperture closes the first nozzle component.