Abstract: A latching solenoid includes a pole member, an armature movable relative to the pole member, a solenoid coil assembly for positioning the armature relative to the pole member, and a magnetic flux shunt structure. The shunt structure bridges the air gap between the pole face and the armature face, providing a low reluctance magnetic flux path between the pole member and the armature to increase the attractive force between the armature and the pole member. The shunt structure can be a saturation tip formed integrally with the armature or a separate flux shunt member configured as a ring which is fixed to the armature. The armature can be maintained latched by the effects of residual magnetism or by a permanent magnet.

Abstract: A valve for dispensing a viscous fluid, includes a valve body defining a fluid chamber and a stepped armature within the fluid chamber. The armature has a large diameter portion maintained spaced apart from an inner surface of the valve body, defining a first air gap therebetween, and a second, smaller diameter portion which engages an inner surface of the valve body, supporting the armature within the valve body and defining a second lower reluctance air gap. A solenoid coil energized by a peak and hold drive current produces an electromagnetic field for moving the armature relative to the magnetic pole piece and the valve body. The second portion of the armature becomes magnetically saturated during the peak portion of the drive current, causing magnetic flux to be diverted through the first portion of the armature.

Abstract: A solenoid includes an armature movable relative to a pole member between a first position and second and third positions, a bias structure maintaining the armature at the first position, and a dual coil assembly driving the armature from the first position to the second and third positions The armature is maintained in the second or third position by permanent magnet latching, residual magnetism latching or a holding current. A magnetic structure for the armature comprises first and second magnet segments and a spacer member for directing magnetic flux produced near ends of the magnetic segments to the armature. A drive circuit for the solenoid includes a delatch circuit for allowing the armature to be returned to the first position by the bias structure in response to loss of power. The axial position of an armature can be determined using comparative inductance test procedure.

Abstract: A solenoid actuated valve includes a valve body and a sleeve armature slidably mounted on the valve body for movement between a flow preventing position and positions away from the flow preventing position. In one embodiment, the sleeve armature and the valve body are configured and arranged to define flow diverters in fluid flow paths to provide flow balance. The movement of the sleeve armature between closed and open positions is controlled by first and second solenoid coils, and, the sleeve armature is maintained in the position to which it has been driven by residual magnetism. In another embodiment, a solenoid actuated valve includes a bias structure for urging the sleeve armature toward the closed position. The solenoid actuated fluid flow control valve is described with reference to an application for inflating inflatable restraints for an occupant of a vehicle.

Abstract: A bidirectional flow control valve has one port co-axial with a tubular spool and another port opening to the side of the spool, with openings formed in the sidewall of the spool to establish communication between the two ports. The end of the spool adjacent to the one port abuts the brim of a tubular hat-shaped insert which extends inside the lumen of the spool to a closed end on the distal side of the other port. Openings are formed in the sidewall of the insert which are in communication with openings in the sidewall of the spool via an annular groove in the exterior of the insert. The insert reacts against flow forces, helps equalize pressures from one end of the spool to the other, and does not increase the pressure drop across the valve.

Abstract: A variable assist power steering system for a motor vehicle has an electronically controlled working pressure valve which normally maintains a working pressure at a relief pressure but increases it in response to steering of the vehicle and according to vehicle status, such as vehicle speed. The system also has electronically controlled direction control valves which are actuated to selectively reduce the working pressure to one side or the other of the steering gear piston so as to match a measured handwheel torque with a value which is desired for the vehicle status.

Abstract: A double latching hydraulic valve of the type that either stays open or stays closed at high pressures and only changes state (between open or closed) at low pressures has three ports, with a main valve between the first and second ports which is opened or closed by a poppet. The first port is always in communication with a pressure chamber which biases the poppet against the main valve seat, and the pressure chamber is placed in communication with the third port, which can be connected to tank pressure, only in the open position of the poppet. Thus, a high pressure is provided in the pressure chamber to keep the poppet closed at high pressures, and a low pressure is provided in the pressure chamber to keep the poppet open at high pressures, without excessive leakage through the valve when it is closed.

Abstract: A proportional pressure control valve has a poppet including a control pin for seating against the seat and which is pressed into a generally tubular armature. One end of the armature proximal to the seat has an enlarged diameter and fits into a cup shaped recess of the housing in an extreme position of the poppet. A smaller diameter of the armature is journaled in a magnetic sleeve bearing at a distal end of the poppet and the control pin is journaled in a sleeve bearing at the proximal end of the popper. A plastic plug covers the distal end of the armature and an annular gap is created at the distal end of the armature bearing between the armature and the housing.

Abstract: The magnetic interface between the housing and armature of a poppet type electromagnetically actuated fluid control valve creates a magnetic flux path through opposing axially and radially facing surfaces of the housing and armature to reduce the pull-in voltage of the valve at large axial gaps between the armature and housing.

Abstract: A hydraulic pressure reducing and relieving valve has a body with input, control and relief ports, a tubular spool slidably received within the body for selectively providing communication between the ports, and a tubular quill within the spool which the spool can slide over. The quill has a lumen which provides communication from one end of the spool to the other, so as to pressure balance the spool with relief pressure, and together with the spool defines a feedback chamber in communication with the control port which generates a force on the spool which opposes the operating force exerted on the spool by a solenoid. The spool may also be biased by a spring in the feedback chamber.

Abstract: A two stage pressure control valve has a poppet movable toward and away from a valve seat to vary the cross-sectional area of a passageway from an inlet to an outlet. The position of the poppet is dependent in part on the difference in pressure between a fluid pressure at the inlet which exerts an force on the poppet in one axial direction and a control pressure which is produced by a fluid flow from the inlet in a chamber downstream from the inlet and which exerts a force on the poppet in the opposite axial direction. The control pressure is controlled by an electromagnetic coil which can be variably energized to move an armature so as to vary a variable restriction downstream from the control pressure so as to vary the control pressure. A tube extends through and forms an axial sliding seal with the poppet and communicates a flow of fluid from the inlet to the variable restriction and the chamber is positioned adjacent to an exterior surface of the tube.

Abstract: A proportional pressure control valve has a metering spool which selectively meters flow between an axial first port and radial second ports. The spool is axially reciprocable with a larger face toward the first port and a smaller face opposite from the first port, with a pressure equalization bore through the spool. A first spring extends between the smaller face of the spool and an armature and the armature is biased to a normal position by a second spring and also has a pressure equalization bore through it. Radial orifices are formed in the end of the armature facing the smaller face of the spool, and the end of the armature seats in the main bore in which the spool is seated. Passageways extend from the orifices to the second ports, and two selectively and variably energizable electromagnetic coils coaxially encircle the armature, one to draw the armature to one side of the normal position and the other to draw the armature to the opposite side.

Abstract: A two-stage, proportional pressure control valve is disclosed which may be used for uni-directional fluid flow. A poppet is movably positioned within a body of the valve. Pressure forces acting on the poppet affect the position of the poppet and thus the magnitude of fluid flow through the valve. A control pressure chamber is defined by the poppet and an orifice plate. The orifice plate includes an passage which may be blocked by an armature. An electromagnetic driver produces a magnetic flux path that is substantially proportional to a variable input current. The electromagnetic driver is operable to move the armature and thereby allow fluid in the control pressure chamber to exit through the passage. The proportional pressure control valve can be incorporated into a damper of a vehicle suspension system where the input current is governed by an electronic control unit of the vehicle.

Abstract: A proportional pressure control valve is disclosed which may be used for uni-directional or bi-directional fluid flow. An electromagnetic driver mounted in a driver cavity of a housing produces a magnetic flux path in response to a variable input current. The magnitude of the flux path is substantially proportinal to the input current. The flux path passes through an armature which is movable within the driver cavity. The armature is connected to a metering spool so that the two move in unison. The metering spool is movable within a main bore between a sealing position and an infinite number of open positions. The position of the metering spool determines the magnitude of fluid communication between pressure ports. A feedback section of the housing establishes a pressure feedback force which impacts on the position of the metering spool and the armature. The valve may also include a spring for biasing the metering spool to a fail-safe position within the housing.

Abstract: A direct-operated, two-way solenoid valve is disclosed. The valve balances the hydraulic flow forces acting on a poppet in order to achieve fast-acting, high-flow operation. The valve has a housing with the poppet mounted in a main bore. The poppet has a sealing end with a longitudinal central bore that is open at the sealing end and terminates in a pressure wall. A radial cross bore in the poppet provides fluid communication between the central bore and an outlet port formed in the housing. The sealing end of the poppet may contact a valve seat to prevent fluid communication between an inlet port formed in the housing and the central bore of the poppet. The sealing end of the poppet is biased into contact with the valve seat to prevent fluid communication between the inlet port and the central bore. An actuator generating a magnetic flux path tends to move the poppet out of contact with the valve seat.