A fuel nozzle metering valve that includes a spool having an inlet port and an outlet flow port, and a retainer assembled to one end of the spool. A valve liner houses a portion of the spool. The spool is configured to move back and forth within the valve liner. The metering valve is biased in a closed position in which the outlet flow port is disposed entirely within the valve liner. The valve is opened when the spool slides within the valve liner such that some portion of the outlet flow port extends beyond an end of the valve liner. The retainer has a stepped portion configured to abut an end of the retainer at a fuel flow pressure below the expected maximum fuel flow pressure to be used in the fuel nozzle metering valve.

There is provided a check valve capable of effectively suppressing the generation of chattering. The check valve includes: a housing including an inlet channel, a valve chest, and an outlet channel; a seat member provided around the inlet channel, the seat member including a seat portion; a valve element pressed against the seat portion to close the inlet channel; a biasing member configured to push the valve element toward a valve seat; a guide portion provided at the housing and configured to guide the valve element when the valve element moves in an axial direction; and a damper chamber communicating with the valve chest through a space between the valve element and the guide portion, the damper chamber being configured to attenuate axial moving force of the valve element. The biasing member is arranged in the valve chest.

A damping valve having a damping valve body with at least one flow channel for damping medium. A valve rod is arranged in the flow channel. The valve rod cooperates with a valve disk and a valve seat surface. The valve rod carries a further valve disk that cooperates with a second valve seat surface. The first valve disk together with the first valve seat surface forms a first partial valve having a first permanently open pilot orifice cross section, and the second valve disk together with the second valve seat surface forms a second partial valve having a second pilot orifice cross section, and a shuttle valve is formed which opens one partial valve and closes the other partial valve depending on the flow direction.

A fuel nozzle metering valve that includes a spool having an inlet port and an outlet flow port, and a retainer assembled to one end of the spool. A valve liner houses a portion of the spool. The spool is configured to move back and forth within the valve liner. The metering valve is biased in a closed position in which the outlet flow port is disposed entirely within the valve liner. The valve is opened when the spool slides within the valve liner such that some portion of the outlet flow port extends beyond an end of the valve liner. The retainer has a stepped portion configured to abut an end of the retainer at a fuel flow pressure below the expected maximum fuel flow pressure to be used in the fuel nozzle metering valve.

The present invention relates to valve apparatus for regulating flow. The apparatus comprises a valve housing having a bore. A piston member (7) is movable within the bore, a first spring member biasing the piston member in a first direction within the bore. A first rod (12) extends through the piston member, the first rod having an end (13) for engaging a second spring member (14) provided between the end (13) and a spring seat (8). The piston member (7) and spring seat define a chamber (9) which houses the second spring member (14) and into which the first rod is slidably received. Further, a second rod extends from the spring seat and is coupled to valve member seat. A damping means is provided to damp the movement of the chamber (9) within the bore.

The invention relates to a compressor unit (200) for a refrigeration system using a refrigerant. The compressor (200) unit includes a centrifugal compressor (201) for compressing the refrigerant, wherein the compressor (201) has a discharge outlet (204) for discharging the compressed refrigerant, and a check valve (1; 100; 301a). An inlet (83) of the check valve (1; 100; 301a) is in fluid connection with the discharge outlet (204) of the compressor (201). In order to provide a more reliable and more quite compressor unit (200), the check valve (1; 100; 301a) is a nozzle check valve including a damping mechanism (41, 50; 50, 141), wherein a closing parameter of the check valve (1; 100; 301a) is between 50 s/m.sup.2 and 2000 s/m.sup.2, wherein the closing parameter is a closing time of the check valve (1; 100; 301a) divided by a port area of the check valve (1; 100; 301a).

A solenoid valve in which a plunger is disposed in an accommodation space inside a solenoid unit, includes: a first breathing flow passage extending in a circumferential direction on an outer periphery of a stator to communicate with an outside of the solenoid valve; a second breathing flow passage extending from the first breathing flow passage in an axial direction at a part in the circumferential direction to communicate with a first space formed between the stator, a sleeve, and a spool; and a third breathing flow passage extending in the axial direction on an inner periphery of the stator to allow communication between the first space and a second space.

A bi-stable solenoid device is proposed, comprising an armature, which is linearly movable between two opposite end stops and comprising a damping unit, which is in communication with the armature and which is configured to dampen and/or to prevent an impact of the armature on at least one of the end stops by a compression and/or an expansion of a gas volume.

The present invention relates to valve apparatus for regulating flow. The apparatus comprises a valve housing having a bore. A piston member (7) is movable within the bore, a first spring member biasing the piston member in a first direction within the bore. A first rod (12) extends through the piston member, the first rod having an end (13) for engaging a second spring member (14) provided between the end (13) and a spring seat (8). The piston member (7) and spring seat define a chamber (9) which houses the second spring member (14) and into which the first rod is slidably received. Further, a second rod extends from the spring seat and is coupled to valve member seat. A damping means is provided to damp the movement of the chamber (9) within the bore.

An assembly for a pressure relief valve includes a valve seat member, a piston and a fluid outlet. The valve seat member includes a fluid inlet, a seat sealing surface and an axial bore. The axial bore includes a first cavity and a second cavity. The seat sealing surface is disposed axially between the first cavity and the second cavity and the fluid inlet is disposed axially between the seat sealing surface and the second cavity. The piston is movable within the axial bore. The piston includes a piston sealing surface, a first cylindrical portion and a second cylindrical portion. The first cylindrical portion configured to be retained by and slidably engage with the first cavity and the second cylindrical portion configured to be retained by and slidably engage with the second cavity. The piston sealing surface is disposed axially between the first cylindrical portion and the second cylindrical portion.