Abstract: The technical field of the invention generally concerns electronically controlled hydraulic valves adapted for use in electro-hydraulically controlled automotive transmissions. The proportional pressure control valve 20 includes a hollow cage 42 pierced by cage tank ports 52, cage clutch ports 54, and by cage pump ports 56. The cage pump ports 56 receive fluid from a pump. The cage clutch ports 54 supply fluid to a hydraulic actuator, such as that for an automotive clutch. The cage clutch ports 54. supply the fluid at a pressure that is proportional to an electrical control signal applied to a solenoid coil 252 of the valve 20. The cage tank ports 52 return fluid from the valve 20 to a tank from which the fluid circulates back to the pump. Located in the cage 42 is a main spool 112 that is movable laterally relative to the cage 42 for controlling a flow of hydraulic fluid between the cage clutch ports 54 and either the cage pump ports 56 or the cage tank ports 52.

Abstract: Proportional variable force solenoid valve for controlling pressure of a fluid in a fluid control system comprises a solenoid housing having therein a solenoid coil, an armature movable in response to electrical current applied to the solenoid coil, and a biasing spring for biasing the armature in a direction to establish a valve fluid pressure response to solenoid coil current. An inner armature end cooperates with or engages a damping member residing in a fluid damping chamber to reduce non-linear valve responses resulting from pressure oscillations in the fluid control system.

Abstract: The pressure of hydraulic fluid which is supplied to the continuously variable transmission in the power train of a motor vehicle is regulated by an apparatus wherein an adjustable pilot valve can receive fluid from a pilot conduit leading to a pressure reducing valve. The pilot conduit normally receives fluid from a further conduit, wherein the pressure of fluid is at least substantially constant, by way of a flow restrictor. A branch conduit serves to evacuate fluid from the pilot conduit into the pilot valve when the latter is at least partially open. The fluid-discharging end of the flow restrictor confronts the inlet of the branch conduit, and such inlet is narrowed to reduce the likelihood of turbulence developing in the fluid stream flowing from the pilot conduit, across the further conduit and into the inlet of the pilot valve.