Variable preferential flow control valve

Claim 2

A control valve comprising a body having a bore therein with an inlet passage intersecting said bore for delivery of fluid to said valve, primary and secondary outlet passages intersecting said bore for exhausting pressure fluid from said valve, an adjustable throttling orifice in the flow path from said inlet passage through said primary outlet, valve means positionable in said bore to proportion flow between said primary and secondary outlet passages, said valve means being pressure actuated responsive to the pressure drop across said orifice to maintain a position whereby pressure fluid is diverted to said secondary outlet to maintain a substantially constant predetermined flow through said primary outlet passage, means for selectively overriding the pressure actuation of said valve means to reposition said valve means in a flow-diverting position connecting said inlet and secondary outlet in hydraulic communication whereby substantially all inlet flow will be diverted to said secondary circuit, said means for selectively overriding the pressure actuation of said valve means including operator means adapted to selectively adjust said throttling orifice to a predetermined opening and selectively actuate said override means to urge said valve means to said flow-diverting position.

Claim 3

The control vale of claim 1 wherein said valve means is a cannelured valve spool and said means for selectively overriding the pressure actuation of said valve spool comprises means for mechanically biasing said valve spool to a position wherein said inlet and secondary outlet passages are in hydraulic communication at said cannelured spool and flow is blocked to said primary outlet.

Claim 4

A control valve comprising a body having a bore therein with an inlet passage intersecting said bore at a first location for delivery of fluid to said valve, secondary and primary outlet passages intersecting said bore at second and third locatioNs respectively adjacent either side of said inlet passage, a cannelured valve spool in said bore having a first position directing substantially all flow to said primary outlet and a second position directing substantially all flow through said secondary outlet and variably positionable therebetween to proportion flow between said primary and secondary outlets, an orifice arranged to receive flow from said primary outlet passage, means associated with said orifice for varying the size thereof, means for transmitting fluid pressure existing upstream of said orifice to one end of said valve spool, passage means downstream of said orifice for transmitting fluid pressure downstream of said orifice to the opposite end of said spool whereby said spool assumes a position in said bore responsive to the pressure drop across said orifice, means for selectively overriding the position of said valve spool to reposition said spool in said second position whereby substantially all inlet flow will be diverted to said secondary outlet, said orifice-varying means operatively engageable with said override means so as to selectively actuate the latter mentioned means.

Claim 5

A control valve comprising a body having a bore therein with an inlet passage intersecting said bore at a first location for delivery of fluid to said valve, secondary and primary outlet passages intersecting said bore at second and third locatioNs respectively adjacent either side of said inlet passage, a cannelured valve spool in said bore having a first position directing substantially all flow to said primary outlet and a second position directing substantially all flow through said secondary outlet and variably positionable therebetween to proportion flow between said primary and secondary outlets, an orifice arranged to receive flow from said primary outlet passage, means associated with said orifice for varying the size thereof, means for transmitting fluid pressure existing upstream of said orifice to one end of said valve spool, passage means downstream of said orifice for transmitting fluid pressure downstream of said orifice to the opposite end of said spool whereby said spool assumes a position in said bore responsive to the pressure drop across said orifice, means for selectively overriding the position of said valve spool to reposition said spool in said second position whereby substantially all inlet flow will be diverted to said secondary outlet, said orifice-varying means operatively engageable with said override means so as to selectively actuate the latter mentioned means.

Claim 6

A control valve comprising a body having a bore therein with an inlet passage intersecting said bore at a first location for delivery of fluid to said valve, secondary and primary outlet passages intersecting said bore at second and third locations respectively adjacent either side of said inlet passage, a movable cannelured valve spool in said bore having a first position directing substantially all inlet flow to said primary outlet and a second position directing substantially all inlet flow through said secondary outlet and positionable therebetween to proportion flow between said primary and secondary outlets, a control orifice arranged to receive flow from said primary outlet passage, piston means having a portion cooperating with said control orifice and movable to vary the size of said control orifice, means for transmitting fluid pressure existing upstream of said orifice to one end of said spool, passage means downstream of said control orifice for transmitting fluid pressure downstream of said orifice to the opposite end of said spool whereby said spool assumes a pressure-balanced position in said bore responsive to the pressure drop across said orifice, a reciprocable plunger adjacent one end of said spool and having a stem extending from said body, said plunger when depressed adapted to override pressure actuation and place said spool in said second position, a control handle for said piston for moving said piston, a cam surface on said handle adapted to engage and depress said plunger when said piston is moved to a predetermined position whereby said inlet and secondary outlet are placed in selective hydraulic communication to divert substantially all inlet flow to said secondary outlet.

Claim 7

A control valve comprising a body having a bore therein with an inlet passage intersecting said bore at a first location for delivery of fluid to said valve, secondary and primary outlet passages intersecting said bore at second and third locations respectively adjacent either side of said inlet passage, a movable cannelured valve spool in said bore having a first position directing substantially all inlet flow to said primary outlet and a second position directing substantially all inlet flow through said secondary outlet and positionable therebetween to proportion flow between said primary and secondary outlets, a control orifice arranged to receive flow from said primary outlet passage, piston means having a portion cooperating with said control orifice and movable to vary the size of said control orifice, means for transmitting fluid pressure existing upstream of said orifice to one end of said spool, passage means downstream of said control orifice for transmitting fluid pressure downstream of said orifice to the opposite end of said spool whereby said spool assumes a pressure-balanced position in said bore responsive to the pressure drop across said orifice, a reciprocable plunger adjacent one end of said spool and having a stem extending from said body, said plunger when depressed adapted to override pressure actuation and place said spool in said second position, a control handle for said piston for moving said piston, a cam surface on said handle adapted to engage and depress said plunger when said piston is moved to a predetermined position whereby said inlet and secondary outlet are placed in selective hydraulic communication to divert substantially all inlet flow to said secondary outlet.

Claim 8

The valve of claim 4 further provided with a second fixed size orifice in said passage means downstream of said first orifice for controlling a pilot flow through said passage, relief valve means in hydraulic communication with said passage means and adapted to be actuated by said pilot flow and operative to relieve fluid from said passage means at a predetermined pressure thereby impressing a pressure differential across said spool to move said spool to said second position.

Claim 9

The valve of claim 5 wherein said pilot relief valve is connected to said secondary outlet passage whereby relieved pressure fluid is delivered to said secondary outlet passage.