Patent ID: 9410397
Filing Date: 2016-08-09
CPC Classification: E21B,F16K

Claim Text:
1. A solenoid-operated valve comprising a valve assembly and a solenoid assembly, the valve assembly comprising: a body with fluid ports for the receipt and delivery of hydraulic control fluid, a valve element disposed in a valve chamber, the valve element being actuable between open and closed positions in order to control the flow of hydraulic control fluid between the fluid ports, the valve element being actuable by a solenoid assembly; the solenoid assembly comprising at least one coil for generating a magnetic field and an actuating member disposed in a solenoid chamber for displacement by the magnetic field, the actuating member being coupled to the valve element, wherein the solenoid chamber is sealed against ingress of hydraulic control fluid from the valve chamber and from the ingress of fluid from the environment surrounding the solenoid assembly, and a movable pressure balancing device provided between the solenoid chamber and the surrounding environment, the balancing device having a first surface exposed to the internal pressure within the solenoid chamber and a second surface exposed to the external pressure of the surrounding environment, the device being movable so as to ensure the forces acting on the first and second surfaces are balanced, and wherein the actuator member comprises a push rod and an armature member, the armature member being fixed to the push rod such that the armature member and the push rod move in unison, the armature member being disposed to receive the magnetic field generated by the at least one coil and being configured to be displaced by a force exerted on the armature member due to the magnetic field, the push rod also being displaced by the force exerted on the armature member due to the fixed connection between the push rod and the armature member.