Three-way valve drivable by a pump, switchable between at least two switch positions wherein a first port is selectively in fluid communication with a second port or with a third port. The three-way valve comprises a movable support and a pair of obstructing members carried by the movable support, at least one of which is responsive to the pressure applied by the pump at the first port, at least one of the movable support and obstructing members being movable due to transitions between an off-state and an on-state of the circulation pump. The obstructing members are adapted to engage reciprocatingly the respective seats of the three-way valve. The obstructing members are capable of changing shape synchronously when the pump switches from the off-state to the on-state.

A hydraulic machine includes: a casing; a differential piston having an upper ring and a lower base, sliding reciprocally in the casing and a cylindrical housing inside the envelope, separating two chambers of the casing; a hydraulic switch conveying liquid to/from the chambers, the switch controlled by movement of the piston and including at least one rod acting on a distribution member that includes an upper valve cooperating with a first seat in the upper ring of the piston and at least one lower valve cooperating with a second seat in the lower base of the piston; and a trigger causing, at the end of the stroke, a sudden change in the position of the switch to reverse the stroke. The lower and upper valve seats accept upper and lower frustoconical portions and a lower frustoconical portion tapering in opposite directions. Also disclosed is a reversible metering pump.

Three-way valve drivable by a pump, switchable between at least two switch positions wherein a first port is selectively in fluid communication with a second port or with a third port. The three-way valve comprises a movable support and a pair of obstructing members carried by the movable support, at least one of which is responsive to the pressure applied by the pump at the first port, at least one of the movable support and obstructing members to being movable due to transitions between an off-state and an on-state of the circulation pump. The obstructing members are adapted to engage reciprocatingly the respective seats of the three-way valve. The obstructing members are capable of changing shape synchronously when the pump switches from the off-state to the on-state.

A check valve is disclosed. The check valve, which is installed in a modulator block of a brake system having a flow path forming a hydraulic circuit, may include: a sleeve housing whose both ends open, the sleeve housing having a discharge flow path, wherein at least one outlet is formed in the discharge flow path; a pair of adaptors respectively coupled with both open ends of the sleeve housing, wherein in one end of each adaptor, an inlet connected to a flow path of the modulator block is formed, and in the other end of the adaptor, a valve seat connected to the discharge flow path is formed; an elastic member disposed in the discharge flow path; and a pair of opening and closing members respectively supported on both ends of the elastic member, and disposed to selectively contact each valve seat of the pair of adaptors.

A check valve is disclosed. The check valve, which is installed in a modulator block of a brake system having a flow path forming a hydraulic circuit, may include: a sleeve housing whose both ends open, the sleeve housing having a discharge flow path, wherein at least one outlet is formed in the discharge flow path; a pair of adaptors respectively coupled with both open ends of the sleeve housing, wherein in one end of each adaptor, an inlet connected to a flow path of the modulator block is formed, and in the other end of the adaptor, a valve seat connected to the discharge flow path is formed; an elastic member disposed in the discharge flow path; and a pair of opening and closing members respectively supported on both ends of the elastic member, and disposed to selectively contact each valve seat of the pair of adaptors.

A loop flushing valve includes a valve body, a fluid passage plug, and a poppet. The valve body includes an internal shoulder and a bore. The fluid passage plug is disposed in the bore and includes a fluid passage in fluid communication with the bore and a system fluid passage. The poppet is captured between the internal shoulder and the fluid passage plug and extends through the valve body.

A valve including a valve housing, a casing, a spring guide, and a retaining cup. The casing may be disposed within the valve housing and may include a bore. The spring guide may be disposed within the bore and the retaining cup may be disposed partially around the casing to engage and retain the spring guide at least partially within the bore of the casing.

A shuttle valve has a valve body including a first valve seat defining a first fluid inlet, a second valve seat defining a second fluid inlet, and a center portion that is connected to the valve seats, the center portion defining a fluid outlet and a bore. A moveable member is moveable within the bore between a first position against the first valve seat and a second position against the second valve seat to control the flow of fluid from either of the first or second inlet to the outlet. The moveable member may be configured to have a unitary construction formed of a single component, by which a unitary shell defines a substantially hollow interior. The moveable member has a hollow interior and a weep hole for equalizing pressure between the hollow interior and exterior of the moveable member.

A hydraulic machine includes: a casing; a differential piston having an upper ring and a lower base, sliding reciprocally in the casing and a cylindrical housing inside the envelope, separating two chambers of the casing; a hydraulic switch conveying liquid to/from the chambers, the switch controlled by movement of the piston and including at least one rod acting on a distribution member that includes an upper valve cooperating with a first seat in the upper ring of the piston and at least one lower valve cooperating with a second seat in the lower base of the piston; and a trigger causing, at the end of the stroke, a sudden change in the position of the switch to reverse the stroke. The lower and upper valve seats accept upper and lower frustoconical portions and a lower frustoconical portion tapering in opposite directions. Also disclosed is a reversible metering pump.

A shuttle valve has a valve body including a first valve seat defining a first fluid inlet, a second valve seat defining a second fluid inlet, and a center portion that is connected to the valve seats, the center portion defining a fluid outlet and a bore. A moveable member is moveable within the bore between a first position against the first valve seat and a second position against the second valve seat to control the flow of fluid from either of the first or second inlet to the outlet. The moveable member may be configured to have a unitary construction formed of a single component, by which a unitary shell defines a substantially hollow interior. The moveable member has a hollow interior and a weep hole for equalizing pressure between the hollow interior and exterior of the moveable member.