Electrohydraulic valve normally operating in pressure relief mode and configured to block fluid flow when actuated

A hydraulic system comprising:

• a source of fluid;
• a reservoir;
• and
• a valve having a first port fluidly coupled to the source of fluid, and a second port fluidly coupled to the reservoir, wherein the valve comprises:
• a pilot seat member comprising:
• (i) a first channel and a second channel, wherein the first channel is fluidly coupled to the first port of the valve, (ii) a pilot seat, and (iii) a pilot sleeve portion comprising a pilot chamber and a cross-hole disposed in an exterior peripheral surface of the pilot sleeve portion,
• a pilot check member disposed in the pilot chamber and subjected to a biasing force of a setting spring disposed in the pilot chamber, wherein the biasing force acts in a distal direction to seat the pilot check member at the pilot seat, wherein the pilot check member is configured to be subjected to fluid force of fluid in the second channel of the pilot seat member acting on the pilot check member in a proximal direction, and
• a solenoid actuator sleeve slidably accommodated about the exterior peripheral surface of the pilot sleeve portion of the pilot seat member, wherein the solenoid actuator sleeve comprises a cross-hole disposed in an exterior peripheral surface of the solenoid actuator sleeve and an annular groove disposed in an interior peripheral surface of the solenoid actuator sleeve, wherein the cross-hole of the solenoid actuator sleeve is fluidly coupled to the second port of the valve, and wherein:
• when the valve is unactuated:
• (i) the cross-hole of the solenoid actuator sleeve is aligned with the cross-hole of the pilot sleeve portion, and (ii) the annular groove fluidly couples the second channel to the first channel to enable generation of pilot flow from the first port to the second port when the fluid force overcomes the biasing force and the pilot check member is unseated, and
• when the valve is actuated, the solenoid actuator sleeve and the annular groove move axially, thereby causing the second channel to be fluidly decoupled from the first channel and precluding pilot flow from the first port to the second port.

A valve comprising:

• a housing having a longitudinal cylindrical cavity therein and having a cross-hole disposed in an exterior peripheral surface of the housing;
• a main sleeve disposed, at least partially, in the longitudinal cylindrical cavity of the housing, wherein the main sleeve includes a first port at a distal end of the main sleeve and includes one or more cross-holes disposed on an exterior peripheral surface of the main sleeve, wherein the cross-hole of the housing and the one or more cross-holes of the main sleeve form a second port;
• a piston disposed within the main sleeve and configured to be axially movable therein, wherein the piston comprises a main chamber therein, and wherein the main chamber is fluidly coupled to the first port via an orifice;
• a pilot seat member comprising:
• (i) a first channel and a second channel, wherein the first channel is fluidly coupled to the first port, (ii) a pilot seat, and (iii) a pilot sleeve portion comprising a pilot chamber and a cross-hole disposed in an exterior peripheral surface of the pilot sleeve portion;
• a pilot check member disposed in the pilot chamber and subjected to a biasing force of a setting spring disposed in the pilot chamber, wherein the biasing force acts in a distal direction to seat the pilot check member at the pilot seat, wherein the pilot check member is configured to be subjected to fluid force of fluid in the second channel of the pilot seat member acting on the pilot check member in a proximal direction;
• and
• a solenoid actuator sleeve slidably accommodated about the exterior peripheral surface of the pilot sleeve portion of the pilot seat member, wherein the solenoid actuator sleeve comprises a cross-hole disposed in an exterior peripheral surface of the solenoid actuator sleeve and an annular groove disposed in an interior peripheral surface of the solenoid actuator sleeve, wherein the cross-hole of the solenoid actuator sleeve is fluidly coupled to the second port of the valve, and wherein the annular groove is configured to selectively fluidly couple the first channel to the second channel based on a position of the solenoid actuator sleeve.