Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
286 words
A pressure compensated directional control valve compRising a directional control valve for selectively operating a fluid motor at controlled speed, said valve having inlet and outlet ports and first and second motor ports for connection to opposite sides of a fluid motor, a longitudinal bore in said control valve, a valve member movable in said bore, said valve member being hollow at each end forming spaced chambers selectively communicating with one another and through the valve member walls with the inlet ports, outlet ports and work ports and with a pair of spaced grooves surrounding the valve member, three spaced annular grooves in the valve walls communicating with the grooves in the valve member, a pressure sensing port communicating with the intermediate groove in the valve walls, a pressure compensating valve having an axial bore, an inlet port connected to the inlet port of said control valve, an outlet port connected to the outlet port of said control valve, a pressure sensing port communicating with the pressure sensing port of the directional control valve, a valve member movable in said axial bore, means biasing said valve member to a position normally blocking said outlet from said inlet port, said valve member having opposite surfaces thereon exposed respectively to fluid pressure from said inlet port and to fluid pressure at said pressure sensing port acting with said biasing means, said valve member being movable in response to fluid pressure differential between its inlet port and pressure sensing port through the pressure sensing port of the directional control valve to connect said inlet and outlet ports for bypassing input pressure fluid to thereby regulate the input flow through said directional control valve to one of said work ports.
Claim 2
Dependent Claim
286 words
A pressure compensated directional control valve compRising a directional control valve for selectively operating a fluid motor at controlled speed, said valve having inlet and outlet ports and first and second motor ports for connection to opposite sides of a fluid motor, a longitudinal bore in said control valve, a valve member movable in said bore, said valve member being hollow at each end forming spaced chambers selectively communicating with one another and through the valve member walls with the inlet ports, outlet ports and work ports and with a pair of spaced grooves surrounding the valve member, three spaced annular grooves in the valve walls communicating with the grooves in the valve member, a pressure sensing port communicating with the intermediate groove in the valve walls, a pressure compensating valve having an axial bore, an inlet port connected to the inlet port of said control valve, an outlet port connected to the outlet port of said control valve, a pressure sensing port communicating with the pressure sensing port of the directional control valve, a valve member movable in said axial bore, means biasing said valve member to a position normally blocking said outlet from said inlet port, said valve member having opposite surfaces thereon exposed respectively to fluid pressure from said inlet port and to fluid pressure at said pressure sensing port acting with said biasing means, said valve member being movable in response to fluid pressure differential between its inlet port and pressure sensing port through the pressure sensing port of the directional control valve to connect said inlet and outlet ports for bypassing input pressure fluid to thereby regulate the input flow through said directional control valve to one of said work ports.
Claim 3
Dependent Claim
85 words
A control valve as claimed in claim 1 wherein the directional control valve is provided with a valve member movable in a bore therein, said valve member being hollow at each end to form chambers therein adapted selectively to communicate through the valve member walls with the inlet port, work ports and outlet port and with the pressure sensing port of the pressure compensating valve through one of the annular grooves in the valve member and the pressure sensing port of the directional control valve.
Claim 4
Dependent Claim
49 words
A control valve as claimed in claim 2 wherein said directional control valve member communicates with the pressure sensing port through the annular grooves in the valve member and walls and the two chambers in the neutral position and through a passageway in each chamber in each work position.
Claim 5
Dependent Claim
26 words
A control valve as claimed in claim 3 wherein the passageways in each chamber communicate with the outlet port when the valve is in neutral position.
Claim 6
Dependent Claim
69 words
A control valve as claimed in claim 1 wherein the pressure compensating valve member is hollow and open at one end, said hollow portion communicating with the inlet port of both the directional control valve and the pressure compensating valve through openings in the sidewalls and discharging through its open end to the outlet port when the pressure in the chamber exceeds the biasing means and pressure sensing pressures.