A valve member for a spring-loaded valve assembly includes a top portion having a spring retaining recess, the spring retaining recess extending into the top portion to form a void space, the void space to receive at least one coil of a spring, the spring retaining recess having a recess diameter that is smaller than a top portion diameter, wherein the recess diameter is larger than a rest diameter of a spring base including the coil, the spring retaining recess blocking expansion of the at least one coil when the spring is compressed. The valve member also includes a bottom portion coupled to the top portion. The valve member further includes a sealing element positioned axially below a shoulder of the top portion and legs coupled to the bottom portion.

Methods and systems are provided for a zero hysteresis valve. In one example, a valve comprises protrusions shaped to maintain a distance between a moveable portion of the valve and a valve seat.

A piston check valve system includes a body including an upstream end and a downstream end, a bonnet secured to a proximal opening of the body, and a piston secured within the body, the piston being moveable between a closed position in which the piston rests upon a valve seat and an open position in which the piston is spaced away from the valve seat. The piston check valve system also includes a retainer configured to guide and retain the piston and to secure the valve seat within the body.

A pressure relief valve includes a valve body including a monitored pressure inlet leading to a monitored pressure region, a piston having a shear seal bore and a surface facing the monitored pressure region, a vent passage and a the shear seal assembly comprising a seal plate having a sealing surface thereon, and the shear seal assembly includes a sealing surface facing the seal plate and having a first annular area, and a first surface having an annular surface area at least twice as large as the first area of the sealing surface, the first surface facing away from the first area, and a biasing seal in contact with the first surface.

Disclosed is a method of applying a biasing force against a piston in a valve as the piston moves along a piston stroke axis in a first direction and an opposing second direction, the piston having a first axial end that is a distal end of the piston, the method including: moving the piston along a piston stroke axis in the first direction and the opposing second direction, wherein while moving the piston along the piston stroke axis: applying a first biasing force in the second direction against the first axial end of the piston from a first spring, and applying a second biasing force in the second direction against the first spring from a second spring.

A hydraulic control apparatus includes an output-side oil passage into which oil from a first oil passage and oil from a second oil passage flow, and a pressure regulating check valve regulating a hydraulic pressure in the second oil passage. The pressure regulating check valve includes first and second elastic portions housed in a spool hole between a valve body and a bottom of the spool hole. A natural length of the second elastic portion is shorter than a distance between the valve body and the bottom when the valve body closes an inflow hole. The second elastic portion applies an elastic force to the valve body in a state in which the valve body opens the inflow hole.

A fluid injection valve comprising: a valve body including a first end having a first opening, a second end having a second opening, an outer surface and an inner surface defining a fluid pathway extending between the first end and the second end; a seat arranged along the fluid pathway; a restriction device selectively abutting the seat; a biasing member arranged in the fluid pathway abutting the restriction device; urging the restriction device against the seat; a biasing element having a biasing force urging the biasing member against the restriction device; and a magnet functionally connected to the biasing element, the magnet selectively forcing the biasing member axially outwardly of the restriction device against the biasing force.

A relief valve that includes a tube; a valve configured to slide along an inner wall of the tube in an axial direction, and a spring that urges the valve, wherein the valve has a hydraulic pressure receiving surface on a first axial side that is one side in the axial direction, and a spring abutment against which the spring abuts, on a second axial side opposite to the first axial side, and the tube has a discharge oil passage having an opening in the inner wall and extending through the inner wall in a radial direction.

A fluid injection valve comprising: a valve body including a first end having a first opening, a second end having a second opening, an outer surface and an inner surface defining a fluid pathway extending between the first end and the second end; a seat arranged along the fluid pathway; a restriction device selectively abutting the seat; a biasing member arranged in the fluid pathway abutting the restriction device; urging the restriction device against the seat; a biasing element having a biasing force urging the biasing member against the restriction device; and a magnet functionally connected to the biasing element, the magnet selectively forcing the biasing member axially outwardly of the restriction device against the biasing force.

Methods and systems are provided for a zero hysteresis valve. In one example, a valve comprises protrusions shaped to maintain a distance between a moveable portion of the valve and a valve seat.