Abstract: A valve assembly including a housing and a first movable member which divides the housing into a control chamber and a main chamber. A second movable member has a first valve part and a second valve part and is movable to engage the first valve part with a corresponding inlet valve part to substantially prevent flow of fluid into the main chamber via an inlet port. The first movable member is provided with an exhaust valve part and is movable to engage the second valve part of the second movable member to substantially prevent flow of pressurized fluid out of the main chamber via an exhaust port. A support part is secured relative to the housing, there being a first seal between the second movable member and the support part and a second seal between the support part and the first movable member.

Abstract: A valve assembly (110) having a housing (124) into which are provided a first port (112), a second port (114) and a third port (116), and in which are located a first movable member (126), a second movable member (132) and a third movable member (152), the first movable member (126) being movable between a first position which causes the second movable member (132) to close the first port (112) to prevent any substantial flow of fluid through the first port (112), whilst the second (114) and third (116) ports remain open, a second position which causes the third movable member (152) to close the third port (116) to prevent any substantial flow of fluid through the third port (116), whilst the first (112) and second (114) ports remain open and flow of fluid between the first (112) and the second (114) part is permitted, and a third position which causes the second movable member (132) to close the first port (112) and the third movable member (152) to close the third port (116) to prevent any substantial flow

Abstract: A valve assembly comprising an inner housing in which is provided a first port, a second port, and a third port, and a valve member assembly which is movable between a first position, a second position, and a third position. An outer housing is separate from and encloses at least part of the inner housing, the outer housing having a first port and a second port, the Inner housing and outer housing each being provided with first mating parts, which engage to provide a substantially fluid tight seal while enclosing a conduit for fluid communication between the first port of the inner housing and the first port of the outer housing, and second mating parts, which engage to provide a substantially fluid tight seal while enclosing a conduit for fluid communication between the second port of the Inner housing and the second port of the outer housing.

Abstract: A valve assembly including a housing and a first movable member which divides the housing into a control chamber and a main chamber. A second movable member has a first valve part and a second valve part and is movable to engage the first valve part with a corresponding inlet valve part to substantially prevent flow of fluid into the main chamber via an inlet port. The first movable member is provided with an exhaust valve part and is movable to engage the second valve part of the second movable member to substantially prevent flow of pressurised fluid out of the main chamber via an exhaust port. A support part is secured relative to the housing, there being a first seal between the second movable member and the support part and a second seal between the support part and the first movable member.

Abstract: A valve assembly comprising an inner housing in which is provided a first port, a second port, and a third port, and a valve member assembly which is movable between a first position, a second position, and a third position. An outer housing is separate from and encloses at least part of the inner housing, the outer housing having a first port and a second port, the Inner housing and outer housing each being provided with first mating parts, which engage to provide a substantially fluid tight seal whilst enclosing a conduit for fluid communication between the first port of the inner housing and the first port of the outer housing, and second mating parts, which engage to provide a substantially fluid tight seal whilst enclosing a conduit for fluid communication between the second port of the Inner housing and the second port of the outer housing.

Abstract: A brake actuator (10) having a housing (12) in which is provided a movable brake actuating assembly (18, 30), the brake actuating assembly (18, 30) being movable between a brake apply position which, in use results in the application of a brake to which the actuator (10) connected, and a brake release position which, in use, results in the release of the brake, the brake actuator (10) further including a lock (34) which is operable to prevent movement of the brake actuating assembly (18, 30) from the brake apply position to the brake release position, the brake actuating assembly (18, 30) including a first movable member (18), a second movable member (30) and a resilient biasing element (32) which extends between the second movable member (30) and the first movable member (18) and which, if one of the first or second movable members (18, 30) is moved relative to the other from an equilibrium separation, exerts a force tending to return the first (18) and second (30) movable members to the equilibrium separati

Abstract: A braking control system comprising a first source of pressurized fluid (82a), a second source of pressurized fluid (82b), a modulator (70), a brake actuator (10), and a plurality of valves (84, 94, 96, 98), the modulator (70) having a supply inlet (72) which may be connected to either of the sources of pressurized fluid via a first fluid flow line which extends between a first one of the valves (84) and the supply inlet (72), and a control inlet (78) which may be connected to either of the sources of pressurized fluid via a second fluid flow line and a second one of the valves (94), a delivery port (74) which is connected an inlet (11) of the actuator (10), and an exhaust outlet (76) which vents to a low pressure region, the modulator (70) being operable to move between a build position in which flow of fluid from the supply inlet (72) to the delivery port (74) is permitted while flow of fluid through the exhaust outlet (76) is substantially prevented, and an exhaust position in which flow of fluid between t

Abstract: A valve assembly (110) having a housing (124) into which are provided a first port (112), a second port (114) and a third port (116), and in which are located a first movable member (126), a second movable member (132) and a third movable member (152), the first movable member (126) being movable between a first position which causes the second movable member (132) to close the first port (112) to prevent any substantial flow of fluid through the first port (112), whilst the second (114) and third (116) ports remain open, a second position which causes the third movable member (152) to close the third port (116) to prevent any substantial flow of fluid through the third port (116), whilst the first (112) and second (114) ports remain open and flow of fluid between the first (112) and the second (114) part is permitted, and a third position which causes the second movable member (132) to close the first port (112) and the third movable member (152) to close the third port (116) to prevent any substantial flow

Abstract: A brake actuator (10) having a housing (12) in which is provided a movable brake actuating assembly (18, 30), the brake actuating assembly (18, 30) being movable between a brake apply position which, in use results in the application of a brake to which the actuator (10) connected, and a brake release position which, in use, results in the release of the brake, the brake actuator (10) further including a lock (34) which is operable to prevent movement of the brake actuating assembly (18, 30) from the brake apply position to the brake release position, the brake actuating assembly (18, 30) including a first movable member (18), a second movable member (30) and a resilient biasing element (32) which extends between the second movable member (30) and the first movable member (18) and which, if one of the first or second movable members (18, 30) is moved relative to the other from an equilibrium separation, exerts a force tending to return the first (18) and second (30) movable members to the equilibrium separati

Abstract: A brake actuator and control valve assembly, the brake actuator (10) having a housing (12) in which is provided a movable assembly (18, 20, 30) including: a brake actuating element (20) which is adapted, in use to be connected to a vehicle brake, the movable assembly (18, 20, 30) being movable from a brake apply position which, in use, results in the application of the brake, and a brake release position which, in use, results in the release of the brake, the brake actuator (10) further including a lock (34, 44, 46) which is operable to change from a locked configuration in which movement of the movable assembly (18, 20, 30) from the brake apply position to the brake release position is prevented, and a released configuration in which movement of the movable assembly (18, 20, 30) from the brake apply position to the brake release position is permitted, wherein the lock (34, 44, 46) includes a fluid pressure operated actuator (34), supply of pressurised fluid to which results in the lock changing from either t

Abstract: A braking control system comprising a first source of pressurised fluid (82a), a second source of pressurised fluid (82b, 90), a modulator (70), a brake actuator (10), and a plurality of valves (84, 94, 96, 98), the modulator (70) having a supply inlet (72) which may be connected to either of the sources of pressurised fluid via a first fluid flow line which extends between a first one of the valves (84) and the supply inlet (72), and a control inlet (78) which may be connected to either of the sources of pressurised fluid via a second fluid flow line and a second one of the valves (94), a delivery port (74) which is connected an inlet (11) of the actuator (10), and an exhaust outlet (76) which vents to a low pressure region, the modulator (70) being operable to move between a build position in which flow of fluid from the supply inlet (72) to the delivery port (74) is permitted whilst flow of fluid through the exhaust outlet (76) is substantially prevented, and an exhaust position in which flow of fluid betw

Abstract: A valve assembly comprising a valve body, a first movable pressure responsive element, and a second pressure responsive movable element, wherein the valve assembly further comprises a resilient biasing element and a movable third pressure responsive element, the resilient biasing element extending between the third pressure responsive element and the valve body and the third pressure responsive element being adapted to act on both the first and second pressure responsive elements to transmit the biasing force of the resilient biasing element to both the first and second pressure responsive elements.

Abstract: A valve assembly having a fluid switch and a main valve for controlling fluid pressure in a working volume in three control states wherein the main valve has three ports for fluid, flow of fluid through a first port and a second port being controlled by the fluid switch being provided with an electrical signal in a first state or a second state respectively, and flow of fluid through the third port being controlled by alternating the signal, preferably rapidly, between the first and second states.