US 12,234,842 B2
Pressure control valve with reduced pilot flow and hydraulic control system with the same
Kevin Cassaidy, Mt. Prospect, IL (US); Joel Mekkes, Traverse City, MI (US); and Matthew Meyer, Lincolnshire, IL (US)
Assigned to HydraForce, Inc., Lincolnshire, IL (US)
Filed by HydraForce, Inc., Lincolnshire, IL (US)
Filed on Oct. 28, 2022, as Appl. No. 18/050,856.
Claims priority of provisional application 63/273,629, filed on Oct. 29, 2021.
Prior Publication US 2023/0146852 A1, May 11, 2023
Int. Cl. F15B 13/04 (2006.01); F16K 11/07 (2006.01)
CPC F15B 13/0402 (2013.01) [F16K 11/0716 (2013.01); F15B 2211/329 (2013.01); F15B 2211/428 (2013.01)] 30 Claims
OG exemplary drawing
 
1. A pressure control valve, comprising:
a body, the body defining an axial bore, a supply port, a work port, and a tank port, each of the supply port, the work port, and the tank port being in fluid communication with the axial bore;
a spool, the spool being disposed within the axial bore of the body and axially movable over a range of travel between: (i) a neutral position, in which the supply port and the work port are in fluid isolation from each other and the work port and the tank port are in fluid communication with each other, and (ii) a shifted position, in which the supply port and the work port are in fluid communication with each other and the work port and the tank port are in fluid isolation from each other;
at least one of the spool and the body defining a pilot flow passage, the pilot flow passage in fluid communication with the supply port and the tank port when the spool is in the neutral position;
a biasing element, the biasing element operatively arranged with the spool to bias the spool to the neutral position;
a pilot flow valve assembly, the pilot flow valve assembly configured to selectively occlude the pilot flow passage, the pilot flow valve assembly including a closure element movable between an open position in which the pilot flow passage is open and a closed position in which the pilot flow passage is occluded;
a pilot flow control assembly, the pilot flow control assembly disposed in the pilot flow passage, the pilot flow control assembly including a first control element and a second control element, the first control element being secured relative to the spool, the second control element being secured relative to the body such that the first control element is axially movable with respect to the second control element upon axial movement of the spool, the first control element and the second control element defining, when the spool is in the neutral position, a restricted pilot flow path along the pilot flow passage including a restriction, the restriction varying as a function of the spool position over the range of travel such that the flow of hydraulic fluid through the pilot flow passage is variably restricted along the range of travel of the spool.