US 12,000,500 B2
Pilot-operated valve with a position indicator
Bernd Zähe, Sarasota, FL (US)
Assigned to Sun Hydraulics, LLC, Sarastoa, FL (US)
Filed by Sun Hydraulics, LLC, Sarasota, FL (US)
Filed on Aug. 1, 2022, as Appl. No. 17/878,115.
Prior Publication US 2024/0035586 A1, Feb. 1, 2024
Int. Cl. F16K 31/122 (2006.01); F15B 11/08 (2006.01); F15B 13/02 (2006.01); F15B 13/04 (2006.01); F16K 11/044 (2006.01); F16K 27/02 (2006.01); F16K 37/00 (2006.01); F15B 13/00 (2006.01)
CPC F16K 31/1221 (2013.01) [F15B 13/027 (2013.01); F15B 13/0405 (2013.01); F16K 11/044 (2013.01); F16K 27/0263 (2013.01); F16K 37/0041 (2013.01); F15B 11/08 (2013.01); F15B 2013/004 (2013.01); F15B 2013/0409 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A valve comprising:
a housing having a longitudinal cylindrical cavity;
a main sleeve disposed, at least partially, within the longitudinal cylindrical cavity of the housing, wherein the main sleeve comprises a poppet seat;
a plurality of ports comprising: a first port, a second port, and a third port configured to receive a pilot fluid signal;
a poppet slidably-accommodated within the main sleeve and configured to be subjected to (i) a first fluid force by fluid of the first port acting on the poppet in a proximal direction toward a poppet seat, wherein the poppet blocks fluid flow to and from the first port when seated at the poppet seat, and (ii) a second fluid force by fluid of the second port acting on the poppet in a distal direction;
a pilot piston configured to be subjected to a pilot fluid force by the pilot fluid signal acting in the distal direction;
a check spring applying a spring force on the poppet in the proximal direction; and
a pilot spring applying a pilot spring force on the pilot piston in the proximal direction, wherein the valve is configured to operate in: (i) a first mode of operation, wherein a pressure differential between the second port and the first port overcomes the spring force of the check spring, causing the poppet to be unseated and allow fluid flow from the second port to the first port, and (ii) a second mode of operation, wherein the pilot fluid force overcomes the pilot spring force, causing the pilot piston to move in the distal direction, thereby causing the poppet to move therewith off the poppet seat, allowing fluid flow from the first port to the second port.
 
7. A hydraulic system comprising:
a source of fluid;
a fluid reservoir;
an actuator having a first chamber and a second chamber therein;
a directional control valve having (i) an inlet port fluidly-coupled to the source of fluid, (ii) a return port fluidly coupled to the fluid reservoir, and (iii) a workport, wherein the directional control valve is configured to fluidly-couple the inlet port to the workport or fluidly couple the workport to the return port;
a valve comprising:
a plurality of ports comprising: (i) a first port fluidly-coupled to the first chamber of the actuator, (ii) a second port fluidly-coupled to the workport of the directional control valve, and (iii) a third port configured to receive a pilot fluid signal from fluid provided to the second chamber of the actuator,
a poppet configured to be subjected to (i) a first fluid force by fluid of the first port acting on the poppet in a proximal direction toward a poppet seat, wherein the poppet blocks fluid flow to and from the first port when seated at the poppet seat, and (ii) a second fluid force by fluid of the second port acting on the poppet in a distal direction,
a pilot piston configured to be subjected to a pilot fluid force by the pilot fluid signal acting in the distal direction,
a check spring applying a spring force on the poppet in the proximal direction, and
a pilot spring applying a pilot spring force on the pilot piston in the proximal direction, wherein the valve is configured to operate in: (i) a first mode of operation, wherein a pressure differential between the second port and the first port overcomes the spring force of the check spring, causing the poppet to be unseated and allow fluid flow from the second port to the first port, thereby allowing fluid flow from the workport of the directional control valve to the first chamber of the actuator, and (ii) a second mode of operation, wherein the pilot fluid force overcomes the pilot spring force, causing the pilot piston to move in the distal direction, thereby causing the poppet to move therewith off the poppet seat, allowing fluid flow from the first port to the second port, thereby allowing fluid flow from the first chamber of the actuator to the workport of the directional control valve;
a position sensor configured to provide sensor information indicating a position of the poppet and a respective position of the pilot piston; and
a controller performing operations comprising:
receiving the sensor information from the position sensor,
when the valve operates in the first mode of operation, estimating fluid flow rate through the valve from the second port to the first port, and
actuating the directional control valve based on estimated fluid flow rate.
 
14. A valve comprising:
a plurality of ports comprising: a first port, a second port, and a third port configured to receive a pilot fluid signal;
a poppet configured to be subjected to (i) a first fluid force by fluid of the first port acting on the poppet in a proximal direction toward a poppet seat, wherein the poppet blocks fluid flow to and from the first port when seated at the poppet seat, and (ii) a second fluid force by fluid of the second port acting on the poppet in a distal direction;
a pilot piston configured to be subjected to a pilot fluid force by the pilot fluid signal acting in the distal direction;
a check spring applying a spring force on the poppet in the proximal direction;
a pilot spring applying a pilot spring force on the pilot piston in the proximal direction, wherein the valve is configured to operate in: (i) a first mode of operation, wherein a pressure differential between the second port and the first port overcomes the spring force of the check spring, causing the poppet to be unseated and allow fluid flow from the second port to the first port, and (ii) a second mode of operation, wherein the pilot fluid force overcomes the pilot spring force, causing the pilot piston to move in the distal direction, thereby causing the poppet to move therewith off the poppet seat, allowing fluid flow from the first port to the second port; and
a position sensor comprising: (i) a poppet activator pin configured as a magnetic target coupled to the poppet, (ii) a piston activator pin configured as a respective magnetic target coupled to the pilot piston, and (iii) a magnetic sensor configured to detect position of the poppet activator pin and the piston activator pin.