Sequence valve with a reverse free flow configuration integrated therewith

A hydraulic system comprising:

• a source of fluid flow;
• a fluid reservoir;
• a first hydraulic cylinder actuator having a first chamber, a second chamber, and a first actuator piston;
• a second hydraulic cylinder actuator having a third chamber, a fourth chamber, and a second actuator piston;
• and
• a valve comprising:
• (i) a first port that is fluidly-coupled to the first chamber of the first hydraulic cylinder actuator, (ii) a second port that is fluidly-coupled to the third chamber of the second hydraulic cylinder actuator, (iii) a pilot port, (iv) a valve piston configured to block fluid flow from the first port to the second port when the valve is in a closed position, (v) a forward flow spring applying a first biasing force on the valve piston in a distal direction, (vi) a reverse flow spring applying a second biasing force on the valve piston in a proximal direction, and (vii) a pressure setting spring applying a third biasing force on a check element in the distal direction, wherein fluid from the first port applies a fluid force on the check element in the proximal direction, and fluid from the pilot port applies a respective fluid force on the check element in the distal direction, wherein the check element is seated when the valve is in the closed position,
• wherein the valve operates in:
• (i) a first mode of operation, wherein fluid from the source of fluid flow fills the first chamber, causing the first actuator piston to move, wherein pressure level of fluid at the first port of the valve increases as the first actuator piston reaches a fully-extend position, wherein increasing pressure level at the first port causes the fluid force of fluid from the first port to overcome the third biasing force of the pressure setting spring and the respective fluid force of fluid from the pilot port, thereby unseating the check element and allowing pilot fluid to flow from the first port to the pilot port, wherein a first net fluid force is applied on the valve piston that overcomes the first biasing force of the forward flow spring, causing the valve piston to move in the proximal direction and allow fluid flow from the first port to the second port, then to the third chamber to move the second actuator piston, and (ii) a second mode of operation, wherein the first port is fluidly-coupled to the fluid reservoir, wherein a second net fluid force is applied on the valve piston that overcomes the second biasing force of the reverse flow spring, causing the valve piston to move in the distal direction and allow fluid flow from the second port to the first port, thereby fluidly coupling the third chamber to the fluid reservoir.

A method comprising:

• operating a valve in a closed position, wherein the valve comprises (i) a valve piston configured to block fluid flow from a first port of the valve to a second port of the valve, (ii) a forward flow spring applying a first biasing force on the valve piston in a distal direction, (iii) a reverse flow spring applying a second biasing force on the valve piston in a proximal direction, and (iv) a pressure setting spring applying a third biasing force on a check element in the distal direction, wherein fluid from the first port applies a fluid force on the check element in the proximal direction, and fluid from a pilot port applies a respective fluid force on the check element in the distal direction, wherein the check element is seated when the valve is in the closed position;
• operating the valve in a first mode of operation, wherein the fluid force of fluid from the first port overcomes the third biasing force of the pressure setting spring and the respective fluid force of fluid from the pilot port, thereby unseating the check element and allowing pilot fluid to flow from the first port to the pilot port, wherein a first net fluid force is applied on the valve piston that overcomes the first biasing force of the forward flow spring, causing the valve piston to move in the proximal direction and allow fluid flow from the first port to the second port;
• and
• operating the valve in a second mode of operation, wherein a second net fluid force is applied on the valve piston that overcomes the second biasing force of the reverse flow spring, causing the valve piston to move in the distal direction and allow fluid flow from the second port to the first port.