Two-port electrohydraulic counterbalance valve

A hydraulic system comprising:

• a tank;
• a hydraulic actuator having a chamber therein;
• and
• a valve having a first port fluidly coupled to the chamber of the hydraulic actuator, and a second port configured to be fluidly coupled to the tank, wherein the valve comprises:
• a main piston comprising:
• (i) a channel that is fluidly coupled to the first port of the valve, (ii) a pilot seat, and (iii) one or more cross-holes fluidly coupled to the second port of the valve,
• a reverse flow piston disposed at the first port of the valve and configured to move axially within the valve,
• a reverse flow check spring that biases the reverse flow piston toward the main piston, such that the reverse flow piston operates as a piston seat for the main piston when the valve is closed,
• a pilot check member configured to be seated at the pilot seat when the valve is closed to block fluid flow from the channel to the one or more cross-holes of the main piston, wherein the pilot check member is configured to be subjected to a fluid force of fluid in the channel of the main piston acting on the pilot check member in a proximal direction,
• a solenoid actuator sleeve,
• a first setting spring disposed within the solenoid actuator sleeve and configured to bias the solenoid actuator sleeve in a distal direction, and
• a second setting spring disposed about an exterior peripheral surface of the solenoid actuator sleeve and configured to bias the pilot check member in the distal direction, such that the first setting spring and the second setting spring cooperate to apply a biasing force in the distal direction on the pilot check member toward the pilot seat against the fluid force.

A method comprising:

• operating a valve at a first pressure setting, wherein a first setting spring disposed within a solenoid actuator sleeve and a second setting spring disposed about an exterior peripheral surface of the solenoid actuator sleeve apply a biasing force to a pilot check member to cause the pilot check member to be seated at a pilot seat formed by a main piston, thereby blocking a pilot flow path through the valve and blocking fluid at a first port of the valve until pressure level of fluid at the first port exceeds the first pressure setting;
• receiving an electric signal energizing a solenoid coil of a solenoid actuator of the valve;
• responsively, causing an armature coupled to the solenoid actuator sleeve to move, thereby compressing the first setting spring and decompressing the second setting spring, causing the biasing force to be reduced, and operating the valve at a second pressure setting that is less than the first pressure setting;
• receiving, at the first port of the valve, pressurized fluid having a particular pressure level that exceeds the second pressure setting such that the pressurized fluid overcomes the biasing force, thereby causing the pilot check member to be unseated and opening the pilot flow path to allow pilot flow from the first port to a second port of the valve;
• and
• in response to pilot flow through the pilot flow path, causing the main piston to move, thereby allowing main flow from the first port to the second port.