Control valve

Claim 2

A control valve comprising a housing, application means movable in said housing for effecting a metered application therethrough of supplied fluid pressure, resiliently urged means drivingly engaged with application means and subjected to a control fluid pressure, said resiliently urged means being movable in response to control fluid pressure acting thereon less than a predetermined value to drive said application means toward a position in said housing effecting the metered application of the supplied fluid pressure therethrough to establish a metered applied fluid pressure in a predetermined ratio with the control fluid pressure, and said resiliently urged means including means for metering the control fluid pressure in excess of the predetermined value to said application means to effect further metering actuation thereof and alter the predetermined ratio between the control and applied fluid pressures.

Claim 3

A control valve comprising a housing, application means movable in said housing for effecting a metered application therethrough of supplied fluid pressure, resiliently urged means drivingly engaged with said application means and adapted to be subjected to a control fluid pressure, said resiliently urged means being initially movable in response to control fluid pressure less than a predetermined value acting thereon to drive said application means toward a position in said housing metering the supplied fluid pressure therethrough to establish a metered applied fluid pressure in a predetermined ratio which the control fluid pressure, an effective area on said application means for subjection to control fluid pressure, and valve means in said resiliently urged means for engagement with said application means and controlling the subjection of the control fluid pressure to said area, said resiliently urged means being further movable in response to control fluid pressure in excess of the predetermined value acting thereon to engage said valve means with said application means and meter control fluid pressure in excess of the predetermined value to said area establishing an assisting force to effect further metering actuation of said application means and increase the metered applied fluid pressure in another predetermined ratio with the control fluid pressure in excess of the predetermined value.

Claim 4

A control valve comprising a housing, application means movable in said housing for effecting a metered application therethrough of supplied fluid pressure, resiliently urged means drivingly engaged with said application means and adapted to be subjected to a control fluid pressure, said resiliently urged means being initially movable in response to control fluid pressure less than a predetermined value acting thereon to drive said application means toward a position in said housing metering the supplied fluid pressure therethrough to establish a metered applied fluid pressure in a predetermined ratio which the control fluid pressure, an effective area on said application means for subjection to control fluid pressure, and valve means in said resiliently urged means for engagement with said application means and controlling the subjection of the control fluid pressure to said area, said resiliently urged means being further movable in response to control fluid pressure in excess of the predetermined value acting thereon to engage said valve means with said application means and meter control fluid pressure in excess of the predetermined value to said area establishing an assisting force to effect further metering actuation of said application means and increase the metered applied fluid pressure in another predetermined ratio with the control fluid pressure in excess of the predetermined value.

Claim 5

A control valve according to claim 2, comprising another effective area on said application means opposed to said first named area and subjected to the applied fluid pressure.

Claim 6

A control valve according to claim 3, wherein said first named area is greater than said other area.

Claim 7

A control valve according to claim 2, wherein said resiliently urged means includes piston means movable in said housing, passage means extending through said piston means and subjected to the control fluid pressure, said valve means being positioned to control said passage means, and resilient means drivingly engaged between said piston means and application means, said piston means being initially movable in response to the control fluid pressure less than the predetermined value acting thereon against said resilient means to drivingly actuate said application means and establish the applied fluid pressure in the first named predetermined ratio and said piston means being thereafter further movable in response to control fluid pressure in excess of the predetermined value acting thereon toward a passage means opening position engaging said valve means with said relay means and metering the control fluid pressure to said area to establish the assisting force and effect the further actuation of said application means.

Claim 8

A control valve according to claim 5, comprising a valve seat on said piston means about said passage means for engagement with said valve means, said valve means being normally urged into engagement with said valve seat to isolate the control fluid pressure from said area, said piston means being movable in response to the control fluid pressure in excess of the predetermined value acting thereon toward its passage means opening position disengaging said valve seat from said valve means when said valve means is engaged with said relay means.

Claim 9

A control valve according to claim 5, comprising a pair of opposed areas on said piston means respectively subjected to the control fluid pressure and the metered control fluid pressure acting on said first named area.

Claim 10

A control valve according to claim 7, wherein one of said opposed area pairs subjected to the metered control fluid pressure acting on said first named area being greater than the other of said opposed area pairs.

Claim 11

A control valve according to claim 2, wherein said application means includes piston means movable in said housing in driven engagement with said resiliently urged means, a chamber in said housing between said piston means and resiliently urged means for subjection to the metered control fluid pressure, said area being on said piston means in said chamber, and other valve means in said housing for engagement with said piston means controlling communication between the supplied and applied fluid pressures, said piston means being initially driven by said resiliently urged means in response to the control fluid pressure less than the predetermined value acting threon to engage and move said other valve means toward a position establishing the applied fluid pressure in the first named predetermined ratio and said piston means being thereafter further driven upon the establishment of the assisting force to aCtuate said other valve means and establish the applied fluid pressure in the other predetermined ratio.

Claim 12

A control valve comprising a housing having inlet, outlet and control ports therein, valve means movable in said housing controlling pressure fluid communication between said inlet and outlet ports, relay means movable in said housing for actuating engagement with said valve means, metering means defining with said relay means an expansible fluid pressure chamber therebetween and movable in said housing for controlling pressure fluid communication between said control port and said chamber, resilient means engaged between said metering and relay means, said metering means being initially movable in response to fluid pressure less than a predetermined value at said control port acting thereon against said resilient means to drive said relay means into engagement with said valve means and move said valve means toward a position effecting pressure fluid communication between said inlet and outlet ports and establishing fluid pressure at said outlet port in a predetermined ratio with that at said control port less than the predetermined value, and an effective area on said relay means in said chamber for subjection to fluid pressure therein, said metering means being further actuated in response to fluid pressure in excess of the predetermined value at said control port acting thereon toward a metering position effecting pressure fluid communicating between said control port and said chamber and establishing a metered control fluid pressure in said chamber acting on said area to create an assisting force further actuating said relay means to increase the established fluid pressure at said outlet port in another predetermined ratio with the fluid pressure in excess of the predetermined value at said control port.

Claim 13

A control valve comprising a housing having inlet, outlet and control ports therein, valve means movable in said housing controlling pressure fluid communication between said inlet and outlet ports, relay means movable in said housing for actuating engagement with said valve means, metering means defining with said relay means an expansible fluid pressure chamber therebetween and movable in said housing for controlling pressure fluid communication between said control port and said chamber, resilient means engaged between said metering and relay means, said metering means being initially movable in response to fluid pressure less than a predetermined value at said control port acting thereon against said resilient means to drive said relay means into engagement with said valve means and move said valve means toward a position effecting pressure fluid communication between said inlet and outlet ports and establishing fluid pressure at said outlet port in a predetermined ratio with that at said control port less than the predetermined value, and an effective area on said relay means in said chamber for subjection to fluid pressure therein, said metering means being further actuated in response to fluid pressure in excess of the predetermined value at said control port acting thereon toward a metering position effecting pressure fluid communicating between said control port and said chamber and establishing a metered control fluid pressure in said chamber acting on said area to create an assisting force further actuating said relay means to increase the established fluid pressure at said outlet port in another predetermined ratio with the fluid pressure in excess of the predetermined value at said control port.

Claim 14

A control valve according to claim 10, wherein said metering means includes piston means movable in said housing and defining with said relay means said chamber, said resilient means being engaged with said piston means, a pair of opposed areas on said piston means for respective subjection to the fluid pressure at said control port and the metered control fluid pressure in said chamber, passage means in said piston means between said control port and said chamber, other valve means positioned to control said passage means, said piston means being initially movable against said resilient means in response to the fluid pressure less than the predetermined value at said control port acting on one of said area pairs to drive said relay means and actuate said first named valve means to establish the fluid pressure at said outlet port in the first named predetermined ratio and said piston means being thereafter further movable against said resilient means in response to the fluid pressure in excess of the predetermined value acting on said one of said area pairs toward a passage means opening position to establish the metered control fluid pressure in said chamber acting on said first named area to create the assisting force.

Claim 15

A control valve according to claim 11, wherein said one of said area pairs is greater than the other of said area pairs.

Claim 16

A control valve according to claim 12, wherein said resilient means includes a spring disposed within said chamber and having opposed end portions in biasing engagement with said metering and relay means.

Claim 17

A control valve according to claim 10, wherein said relay means includes piston means novable in said housing and defining with said metering means said chamber, said resilient means being engaged with said piston means and said area being on said piston means, extension means on said piston means for actuating engagement with said valve means.

Claim 18

A control valve according to claim 14, comprising another area on said piston means opposed to said first named area and subjected to the established fluid pressure at said outlet port.

Claim 19

A control valve according to claim 14, wherein said meterIng means includes other piston means movable in said housing and defining with said first named piston means said chamber, said resilient means including spring means engaged between said first named and other piston means within said chamber, a pair of opposed areas on said other piston means for respective subjection to the fluid pressure at said control port and the metered control fluid pressure in said chamber, passage means in said other piston means between said control port and said chamber, other valve means in said other piston means and positioned to control said passage means, said other piston means being initially movable against said spring means in response to the fluid pressure less than the predetermined value at said control port acting on one of said area pairs to drive said first named piston and engage said extension means with said first named valve means effecting the actuation thereof to establish the fluid pressure at said outlet port in the first named predetermined ratio with the fluid pressure less than the predetermined value at said control port, other extension means on said first named piston means for engagement with said other valve means, said other piston means also being further movable against said spring means in response to the fluid pressure in excess of the predetermined value at said control port acting on said one of said area pairs toward a passage means opening position engaging said other valve means with said other extension means to establish the metered control fluid pressure in said chamber acting on said first named area to create the assisting force.

Claim 20

A control valve comprising a housing having inlet, outlet and control ports therein, a valve movable in said housing controlling communication between said inlet and outlet ports, a piston movable in said housing for actuating said valve, a differential piston movable in said housing and defining with said first named piston an expansible fluid pressure chamber therebetween including larger and smaller surfaces respectively presented to said control port and chamber, a spring biased between said first named and differential pistons, said differential piston being initially movable against said spring in response to fluid pressure less than a predetermined value delivered to said control port to drive said first named piston into engagement with said valve means and actuate said valve means toward a position establishing fluid pressure at said outlet port in a predetermined ratio with the fluid pressure less than the predetermined value delivered to said control port, a passage through said differential piston communicating said control port and chamber, a valve positioned to control said passage, said differential piston being further movable against said spring in response to fluid pressure in excess of the predetermined value delivered to said control port toward a passage opening position to establish a reduced control fluid pressure in said chamber, and another surface on said first named piston presented to said chamber, the reduced control fluid pressure in said chamber acting on said other surface to establish an assisting force further actuating said first named piston and valve to increase the established fluid pressure at said outlet port in another predetermined ratio with the fluid pressure in excess of the predetermined value delivered to said control port.

Claim 21

A control valve comprising a housing having inlet, outlet and control ports therein, a valve movable in said housing controlling communication between said inlet and outlet ports, a piston movable in said housing for actuating said valve, a differential piston movable in said housing and defining with said first named piston an expansible fluid pressure chamber therebetween including larger and smaller surfaces respectively presented to said control port and chamber, a spring biased between said first named and differential pistons, said differential piston being initially movable against said spring in response to fluid pressure less than a predetermined value delivered to said control port to drive said first named piston into engagement with said valve means and actuate said valve means toward a position establishing fluid pressure at said outlet port in a predetermined ratio with the fluid pressure less than the predetermined value delivered to said control port, a passage through said differential piston communicating said control port and chamber, a valve positioned to control said passage, said differential piston being further movable against said spring in response to fluid pressure in excess of the predetermined value delivered to said control port toward a passage opening position to establish a reduced control fluid pressure in said chamber, and another surface on said first named piston presented to said chamber, the reduced control fluid pressure in said chamber acting on said other surface to establish an assisting force further actuating said first named piston and valve to increase the established fluid pressure at said outlet port in another predetermined ratio with the fluid pressure in excess of the predetermined value delivered to said control port.