Control valve and system

Claim 2

A control valve comprising a housing having a pressure fluid flow passage therethrough, a pair of proportioning members respectively movable in said flow passage in series flow relation for performing proportioning operations on the pressure fluid in said flow passage, one of said proportioning members being initially movable in response to fluid pressure of a predetermined value toward a position in said flow passage isolating the pressure fluid upstream thereof from that downstream thereof and being thereafter further movable in response to increases in the fluid pressure upstream thereof toward a metering position effecting a metered increase in the fluid pressure downstream thereof in one predetermined ratio with the increased fluid pressure upstream thereof, and the other of said proportioning members being initially movable in response to fluid pressure of another predetermined value predeterminately different than the first named predetermined value toward a position in said flow passage isolating the fluid pressure upstream thereof from that downstream thereof and being thereafter further movable in response to increases in the fluid pressure upstream thereof toward a metering position effecting a metered increase in the fluid pressure downstream thereof in another predetermined ratio predeterminately different than the first named predetermined ratio with the increased fluid pressure upstream thereof, and the metered fluid pressure of one of said one and other proportioning members having a continuing and variable affect on the metered fluid pressure of the other of said one and other proportioning members wherein the metered fluid pressure acting on the downstream one of said one and other proportioning members is a function of the product of the first named and other predetermined ratios.

Claim 3

A control valve according to claim 1, wherein one of said first named and other predetermined ratios is greater than the other of said first named and other predetermined ratios.

Claim 4

A control valve according to claim 1, wherein one of said first named and other predetermined ratios is greater than the other of said first named and other predetermined ratios.

Claim 5

A control valve according to claim 1, wherein said one proportioning member includes a proportioning piston movable in said housing, and resilient means engaged with said proportioning piston, said proportioning piston being movable against the force of said resilient means toward its isolating position and the force of said resilient means assisting movement of said proportioning piston toward its metering position.

Claim 6

A control valve according to claim 1, wherein said other proportioning member includes a proportioning piston movable in said housing, and resilient means engaged with said proportioning piston, said proportioning piston being movable against the force of said resilient means toward its isolating position and the force of said resilient means assisting movement of said proportioning piston toward its metering position.

Claim 7

A control valve according to claim 1, wherein said one and other proportioning members include first and second proportioning piston means slidable in said housing, and first and second spring means engaged with said first and second piston means, the forces of said first and second spring means opposing and assisting movement of said first and second proportioning piston means toward their isolating and metering positions, respectively.

Claim 8

A control valve according to claim 5, comprising first and second valve seats in said housing about said flow passage for engagement with said first and second proportioning piston means, said first and second valve seats being engaged by said first and second proportioning piston means in their isolating positions and said first and second proportioning piston means being disengaged from said first and second valve seats in their metering positions, respectivEly.

Claim 9

A control valve according to claim 6, comprising first and second valve means on said first and second proportioning piston means for engagement with said first and second valve seats, said first and second valve means being engaged with said first and second valve seats when said first and second proportioning piston means are in their isolating positions and disengaged therefrom when said first and second proportioning piston means are in their metering positions, respectively.

Claim 10

A control valve according to claim 5, comprising first and second pairs of opposed effective areas on said first and second proportioning piston means subjected to fluid pressure immediately upstream and downstream thereof in said flow passage, respectively, the fluid pressure immediately upstream of said first and second proportioning piston means in excess of said first named and other predetermined values acting on one of the areas of said first and second area pairs to assist said first and second spring means urging said first and second proportioning piston means toward their metering positions and the fluid pressure immediately downstream of said first and second proportioning piston means acting on the other of said areas of said first and second area pairs to oppose movement of said first and second proportioning piston means to their metering positions, respectively.

Claim 11

A control valve comprising a housing having an inlet and outlet port therein, proportioning means movable in said housing for controlling pressure fluid communication between said inlet and outlet ports, said proportioning means being movable in response to fluid pressure at said inlet port in excess of a predetermined value to effect metered pressure fluid communication between said inlet and outlet port and establish a reduced fluid pressure at said outlet port in a predetermined ratio with that at said inlet port, and other proportioning means movable in said housing in series flow relation with said first named proportioning means between said first named proportioning means and said outlet port for controlling pressure fluid communication therebetween, said other proportioning means being movable in response to the reduced fluid pressure of another predetermined value predeterminately in excess of the first named predetermined value to effect metered pressure fluid communication between said first named proportioning means and said outlet port to establish another reduced fluid pressure at said outlet port in another predetermined ratio with the first named reduced fluid pressure wherein the other reduced fluid pressure is a function of the product of the first named and other predetermined ratios.

Claim 12

A control valve comprising a housing having an inlet and outlet port therein, proportioning means movable in said housing for controlling pressure fluid communication between said inlet and outlet ports, said proportioning means being movable in response to fluid pressure at said inlet port in excess of a predetermined value to effect metered pressure fluid communication between said inlet and outlet port and establish a reduced fluid pressure at said outlet port in a predetermined ratio with that at said inlet port, and other proportioning means movable in said housing in series flow relation with said first named proportioning means between said first named proportioning means and said outlet port for controlling pressure fluid communication therebetween, said other proportioning means being movable in response to the reduced fluid pressure of another predetermined value predeterminately in excess of the first named predetermined value to effect metered pressure fluid communication between said first named proportioning means and said outlet port to establish another reduced fluid pressure at said outlet port in another predetermined ratio with the first named reduced fluid pressure wherein the other reduced fluid pressure is a function of the product of the first named and other predetermined ratios.

Claim 13

A control valve comprising a housing, first inlet and outlet chambers in said housing, a first proportioning member movable in said housing for controlling pressure fluid communication between said first inlet and outlet chambers, said first proportioning member being initially movable in response to fluid pressure in said first inlet and outlet chambers of a predetermined value toward a position isolating said first inlet chamber from said first outlet chamber and being thereafter further movable in response to increases in the fluid pressure in said first inlet chamber in excess of the predetermined value toward a position effecting metered pressure fluid communication between said first inlet and outlet chambers to establish fluid pressure in said first outlet chamber in a predetermined ratio with the increased fluid pressure in said first inlet chamber, second inlet and outlet chambers in said housing, means in said housing connecting said first outlet chamber in open pressure fluid communication with said second inlet chamber, and a second proportioning member movable in said housing for controlling pressure fluid communication between said second inlet and outlet chambers, said second proportioning member being initially movable in response to the established fluid pressure in said first outlet chamber aNd said second inlet and outlet chambers of another predetermined value different than the first named predetermined value toward a position isolating said second inlet chamber from said second outlet chamber and being thereafter further movable in response to increases in the established fluid pressure in said first outlet chamber and said second inlet chamber in excess of the other predetermined value toward a position effecting metered pressure fluid communication between said second inlet and outlet chambers to establish another fluid pressure in said second outlet chamber in another predetermined ratio with the increased established fluid pressure in said first outlet chamber and second inlet chamber wherein the fluid pressure established in said second outlet chamber is a function of the product of the first named and other ratios.

Claim 14

A control valve comprising a housing, first inlet and outlet chambers in said housing, a first proportioning member movable in said housing for controlling pressure fluid communication between said first inlet and outlet chambers, said first proportioning member being initially movable in response to fluid pressure in said first inlet and outlet chambers of a predetermined value toward a position isolating said first inlet chamber from said first outlet chamber and being thereafter further movable in response to increases in the fluid pressure in said first inlet chamber in excess of the predetermined value toward a position effecting metered pressure fluid communication between said first inlet and outlet chambers to establish fluid pressure in said first outlet chamber in a predetermined ratio with the increased fluid pressure in said first inlet chamber, second inlet and outlet chambers in said housing, means in said housing connecting said first outlet chamber in open pressure fluid communication with said second inlet chamber, and a second proportioning member movable in said housing for controlling pressure fluid communication between said second inlet and outlet chambers, said second proportioning member being initially movable in response to the established fluid pressure in said first outlet chamber aNd said second inlet and outlet chambers of another predetermined value different than the first named predetermined value toward a position isolating said second inlet chamber from said second outlet chamber and being thereafter further movable in response to increases in the established fluid pressure in said first outlet chamber and said second inlet chamber in excess of the other predetermined value toward a position effecting metered pressure fluid communication between said second inlet and outlet chambers to establish another fluid pressure in said second outlet chamber in another predetermined ratio with the increased established fluid pressure in said first outlet chamber and second inlet chamber wherein the fluid pressure established in said second outlet chamber is a function of the product of the first named and other ratios.

Claim 15

In a hydraulic brake system having a fluid pressure responsive brake, a master cylinder for establishing fluid pressure in said system to energize said brake, and a pair of proportioning valve means in said system in series flow relation for performing proportioning operations on the established fluid pressure in said system, said proportioning valve means being generally operable in response to fluid pressures immediately upstream thereof of one and other predetermined values to reduce the fluid pressures immediately downstream thereof in said system in one and other ratios respectively, wherein the reduced fluid pressure of the downstream one of said proportioning valve means is a function of the one and other ratios.

Claim 16

In a hydraulic brake system having a fluid pressure responsive brake, a master cylinder for establishing fluid pressure in said system to energize said brake, and a pair of proportioning valve means in said system in series flow relation for performing proportioning operations on the established fluid pressure in said system, said proportioning valve means being generally operable in response to fluid pressures immediately upstream thereof of one and other predetermined values to reduce the fluid pressures immediately downstream thereof in said system in one and other ratios respectively, wherein the reduced fluid pressure of the downstream one of said proportioning valve means is a function of the one and other ratios.

Claim 17

In a hydraulic brake system having at least one pressure supply and at least one pressure responsive brake, and a pair of proportioning valves in series flow relation in said system with said proportioning valves being operable generally for reducing the pressure from said supply to said brake under preselected conditions, one of said proportioning valves being responsive to the pressure of said supply in excess of a predetermined value to effect a reduced pressure through the other of said proportioning valves to said brake in a predetermined ratio with the pressure at said supply and said other proportioning valve being responsive to the reduced pressure in excess of another predetermined value predeterminately in excess of the first named predetermined value to effect another reduced fluid pressure to said brake in another predetermined ratio with the first named reduced fluid pressure wherein the other reduced fluid pressure is a function of the product of the first named and other ratios.

Claim 18

In a hydraulic brake system having at least one pressure supply and at least one pressure responsive brake, and a pair of proportioning valves in series flow relation in said system with said proportioning valves being operable generally for reducing the pressure from said supply to said brake under preselected conditions, one of said proportioning valves being responsive to the pressure of said supply in excess of a predetermined value to effect a reduced pressure through the other of said proportioning valves to said brake in a predetermined ratio with the pressure at said supply and said other proportioning valve being responsive to the reduced pressure in excess of another predetermined value predeterminately in excess of the first named predetermined value to effect another reduced fluid pressure to said brake in another predetermined ratio with the first named reduced fluid pressure wherein the other reduced fluid pressure is a function of the product of the first named and other ratios.

Claim 19

In a hydraulic brake system having a pressure responsive brake and a pressure supply for selectively pressurizing said brake, and a pair of proportioning valves connected in series flow relation in said system for respectively controlling the application to said brakes of pressure supplied from said supply under preselected conditions, one of said proportioning valves being initially movable in response to the supplied and applied pressures of a predetermined value toward a position isolating said supply from the other of said proportioning valves and said brake and being thereafter further movable in response to increases in the supplied pressure in excess of the predetermined value toward a metering position to effect of a metered increase in the pressure applied through the other of said proportioning valves to said brake in a predetermined ratio with the increased supplied pressure and said other proportioning valve being initially movable in response to the pressure applied from said one proportioning valve to said brake of another predetermined value predeterminately in excess of the first named predetermined value toward a position isolating said one proportioning valve from said brake and being thereafter further movable in response to increases in the pressure applied from said one proportioning valve in excess of the other predetermined value toward a metering position to effect a further metered increase in the pressure apPlied to said brake in another predetermined ratio with the increased pressure applied from said one proportioning valve wherein the fluid pressure applied to said brake is a function of the product of the first named and other predetermined ratios.

Claim 20

In a hydraulic brake system having a pressure responsive brake and a pressure supply for selectively pressurizing said brake, and a pair of proportioning valves connected in series flow relation in said system for respectively controlling the application to said brakes of pressure supplied from said supply under preselected conditions, one of said proportioning valves being initially movable in response to the supplied and applied pressures of a predetermined value toward a position isolating said supply from the other of said proportioning valves and said brake and being thereafter further movable in response to increases in the supplied pressure in excess of the predetermined value toward a metering position to effect of a metered increase in the pressure applied through the other of said proportioning valves to said brake in a predetermined ratio with the increased supplied pressure and said other proportioning valve being initially movable in response to the pressure applied from said one proportioning valve to said brake of another predetermined value predeterminately in excess of the first named predetermined value toward a position isolating said one proportioning valve from said brake and being thereafter further movable in response to increases in the pressure applied from said one proportioning valve in excess of the other predetermined value toward a metering position to effect a further metered increase in the pressure apPlied to said brake in another predetermined ratio with the increased pressure applied from said one proportioning valve wherein the fluid pressure applied to said brake is a function of the product of the first named and other predetermined ratios.

Claim 21

In a hydraulic brake system having a pressure responsive brake, a pressure supply in said system for selectively pressurizing said brake, and a device connected in said system between said supply and brake for controlling the application to said brakes of pressure supplied from said supply under preselected conditions, said device comprising passage means connected with said supply and said brakes, a first proportioning valve movable in said passage means in response to pressure applied therethrough from said supply to said brake of a predetermined value toward a position closing said passage means and being thereafter further movable in response to increases in the pressure from said source in excess of the predetermined value toward another position in said passage means establishing metered communication therethrough between said supply and brake to effect a metered increase in the pressure applied to said brake in a predetermined ratio with the increased pressure from said supply, and a second proportioning valve movable in said passage means between said first proportioning valve and said brake, said second proportioning valve being movable in response to the pressure applied therethrough from said first proportioning valve to said brake of another predetermined value predeterminately greater than the first named predetermined value toward a position closing said passage means and being thereafter further movable in response to increases in the pressure from said first proportioning valve in excess of the other predetermined value toward another position in said passage means establishing metered communication therethrough between said first proportioning valve and said brake to effect another metered increase in the pressure applied to said brake in another predetermined ratio with the increased pressure from said first proportioning valve wherein the value of the fluid pressure applied to said brake from said second proportioning valve is a function of the product of the first named and other predetermined ratios.

Claim 22

In a hydraulic brake system having a pressure responsive brake, a pressure supply in said system for selectively pressurizing said brake, and a device connected in said system between said supply and brake for controlling the application to said brakes of pressure supplied from said supply under preselected conditions, said device comprising passage means connected with said supply and said brakes, a first proportioning valve movable in said passage means in response to pressure applied therethrough from said supply to said brake of a predetermined value toward a position closing said passage means and being thereafter further movable in response to increases in the pressure from said source in excess of the predetermined value toward another position in said passage means establishing metered communication therethrough between said supply and brake to effect a metered increase in the pressure applied to said brake in a predetermined ratio with the increased pressure from said supply, and a second proportioning valve movable in said passage means between said first proportioning valve and said brake, said second proportioning valve being movable in response to the pressure applied therethrough from said first proportioning valve to said brake of another predetermined value predeterminately greater than the first named predetermined value toward a position closing said passage means and being thereafter further movable in response to increases in the pressure from said first proportioning valve in excess of the other predetermined value toward another position in said passage means establishing metered communication therethrough between said first proportioning valve and said brake to effect another metered increase in the pressure applied to said brake in another predetermined ratio with the increased pressure from said first proportioning valve wherein the value of the fluid pressure applied to said brake from said second proportioning valve is a function of the product of the first named and other predetermined ratios.

Claim 23

A control valve comprising a housing having a pair of sets of inlet and outlet chambers therein connected in series flow relation, and a pair of proportioning members movable in said housing between the inlet and outlet chambers of said chamber sets for performing fluid pressure proportioning operations therebetween under preselected conditions, said proportioning members being operable generally in response to fluid pressures in excess of one and other predetermined values in said inlet chambers of said chamber sets to reduce the fluid pressures in the outlet chambers of said chamber sets in one and other predetermined ratios with the fluid pressures in said inlet chambers of said chamber sets, respectively, and the reduced fluid pressure in one of the outlet chambers of said chamber sets acting on one of said proportioning members having a continued and varying affect on the reduced fluid pressure in the other of the outlet chambers of said chamber sets acting on the other of said proportioning members wherein the reduced fluid pressure acting on the downstream one of said one and other proportioning members is a function of the product of the one and other ratios.

Claim 24

A control valve comprising a housing having a pair of sets of inlet and outlet chambers therein connected in series flow relation, and a pair of proportioning members movable in said housing between the inlet and outlet chambers of said chamber sets for performing fluid pressure proportioning operations therebetween under preselected conditions, said proportioning members being operable generally in response to fluid pressures in excess of one and other predetermined values in said inlet chambers of said chamber sets to reduce the fluid pressures in the outlet chambers of said chamber sets in one and other predetermined ratios with the fluid pressures in said inlet chambers of said chamber sets, respectively, and the reduced fluid pressure in one of the outlet chambers of said chamber sets acting on one of said proportioning members having a continued and varying affect on the reduced fluid pressure in the other of the outlet chambers of said chamber sets acting on the other of said proportioning members wherein the reduced fluid pressure acting on the downstream one of said one and other proportioning members is a function of the product of the one and other ratios.

Claim 25

A control valve comprising a housing having a pair of sets of inlet and outlet chambers therein, a pair of proportioning members movable in said housing between the inlet and outlet chambers of said chamber sets for performing fluid pressure proportioning operations therebetween, respectively, said proportioning members being operable generally in response to the fluid pressures in said inlet chambers of said chamber sets in excess of one and other predetermined values to reduce the fluid pressures in the outlet chambers of said chamber sets in one aNd other predetermined ratios with the fluid pressures in the inlet chambers of said chamber sets, respectively, means in said housing connecting one of the outlet chambers of one of said chamber sets in pressure fluid communication with one of the inlet chambers of the other of said chamber sets wherein the reduced fluid pressure in one of said one and the other of said outlet chambers of said chamber sets acting on the down-stream one of said proportioning members is a function of the product of the one and other ratios.

Claim 26

A control valve comprising a housing having a pair of sets of inlet and outlet chambers therein, a pair of proportioning members movable in said housing between the inlet and outlet chambers of said chamber sets for performing fluid pressure proportioning operations therebetween, respectively, said proportioning members being operable generally in response to the fluid pressures in said inlet chambers of said chamber sets in excess of one and other predetermined values to reduce the fluid pressures in the outlet chambers of said chamber sets in one aNd other predetermined ratios with the fluid pressures in the inlet chambers of said chamber sets, respectively, means in said housing connecting one of the outlet chambers of one of said chamber sets in pressure fluid communication with one of the inlet chambers of the other of said chamber sets wherein the reduced fluid pressure in one of said one and the other of said outlet chambers of said chamber sets acting on the down-stream one of said proportioning members is a function of the product of the one and other ratios.

Claim 27

A control valve according to claim 16, wherein one of said one and other predetermined ratios is greater than the other thereof.

Claim 28

A control valve according to claim 16, wherein one of said one and other predetermined values is greater than the other thereof.

Claim 29

A control valve according to claim 16, wherein said proportioning members include a pair of resiliently urged means, said resiliently urged means being movable against their own forces in response to the fluid pressures in said inlet and outlet chambers of said chamber sets of the one and other predetermined values toward positions isolating said inlet and outlet chambers of said chamber sets and the forces of said resiliently urged means thereafter assisting the fluid pressures in excess of the one and other predetermined values in said inlet chambers of said chamber sets acting on said resiliently urged means to urge said resiliently urged means toward a metering position effecting metered pressure fluid communication between the inlet and outlet chambers of said chamber sets and establishing metered fluid pressures in the outlet chambers of said chamber sets in the one and other predetermined ratios with the fluid pressures in the inlet chambers of said chamber sets, respectively.

Claim 30

A control valve according to claim 19, wherein said resiliently urged means include a pair of proportioning pistons, and a pair of resilient means engaged with proportioning pistons, said proportioning pistons being movable against the forces of said resilient means toward their isolating positions and the forces of said resilient means urging said proportioning pistons toward their metering positions, respectively.

Claim 31

A control valve according to claim 20, comprising a pair of valve seats in said housing between said inlet and outlet chambers of said chamber sets for engagement with said proportioning pistons, said proportioning pistons being engaged with said valve seats in their isolating positions and being disengaged from said valve seats in their metering positions, respectively.

Claim 32

A control valve according to claim 21, comprising a pair of valve means on said proportioning pistons for engagement with said valve seats, said valve means being engaged with said valve seats in the isolating positions of said proportioning pistons and being disengaged from said valve seats in the metering positions of said proportioning pistons, respectively.

Claim 33

A control valve according to claim 20, comprising a pair of opposed areas on said proportioning pistons subjected to the fluid pressures in the inlet and outlet chambers of said chamber sets, respectively, the fluid pressures in excess of the one and other values in said inlet chambers of said chamber sets acting on one of the opposed areas of said proportioning pistons to assist said resilient means and urge said proportioning pistons toward their metering positions and the fluid pressures in said outlet chambers of said chamber sets acting on the other of said opposed areas of said proportioning pistons to oppose movement thereof toward their metering positions, respectively.

Claim 34

A control valve according to claim 23, wherein said other area of each of said proportioning pistons is predeterminately greater than said one area of each of said proportioning pistons.

Claim 35

A control valve comprising a housing having inlet and outlet ports therein, a pair of proportioning valves movable in said housing in series flow relation between said inlet and outlet portS and operable generally to perform proportioning operations on pressure fluid flow from said inlet port to said outlet port under preselected conditions, respectively, each of said proportioning valves having inlet and outlet sides, one of said proportioning valves being responsive to fluid pressure in excess of a predetermined value at one of said inlet port and the outlet side of the other of said proportioning valves to proportionally reduce the fluid pressure at one of said outlet ports and the inlet side of said other proportioning valve in a predetermined ratio with the fluid pressure acting thereon in excess of the predetermined value at the one of said inlet port and the outlet said of said other proportioning valve, and said other proportioning valve being responsive to the fluid pressure in excess of another predetermined value at one of said inlet port and the outlet side said one proportioning valve to proportionally reduced the fluid pressure at one of said outlet port and the inlet side of said one proportioning valve in another predetermined ratio with the fluid pressure acting thereon in excess of the other predetermined value at the one of said inlet port and the outlet side of said one proportioning valve wherein the reduced fluid pressure acting on the downstream one of said one and other proportioning valves is a function of the first named and other ratios.

Claim 36

A control valve comprising a housing having inlet and outlet ports therein, a pair of proportioning valves movable in said housing in series flow relation between said inlet and outlet portS and operable generally to perform proportioning operations on pressure fluid flow from said inlet port to said outlet port under preselected conditions, respectively, each of said proportioning valves having inlet and outlet sides, one of said proportioning valves being responsive to fluid pressure in excess of a predetermined value at one of said inlet port and the outlet side of the other of said proportioning valves to proportionally reduce the fluid pressure at one of said outlet ports and the inlet side of said other proportioning valve in a predetermined ratio with the fluid pressure acting thereon in excess of the predetermined value at the one of said inlet port and the outlet said of said other proportioning valve, and said other proportioning valve being responsive to the fluid pressure in excess of another predetermined value at one of said inlet port and the outlet side said one proportioning valve to proportionally reduced the fluid pressure at one of said outlet port and the inlet side of said one proportioning valve in another predetermined ratio with the fluid pressure acting thereon in excess of the other predetermined value at the one of said inlet port and the outlet side of said one proportioning valve wherein the reduced fluid pressure acting on the downstream one of said one and other proportioning valves is a function of the first named and other ratios.

Claim 37

A brake system comprising a brake, fluid pressure generating means for applying fluid pressure to said brake to effect energization thereof, and a pair of proportioning valves connected in said system in series flow relation between said generating means and said brake and operable generally to perform proportioning operations on the applied fluid pressure in said system under preselected conditions, respectively, one of said proportioning valves being responsive to the fluid pressure applied thereto in excess of a predetermined value from one of said generating means and the other of said proportioning valves to proportionally reduce in a predetermined ratio the fluid pressure applied to one of said brake and said other proportioning valve, and said other proportioning valve being responsive to the fluid pressure applied thereto in excess of another predetermined value from one of said generating means and said one proportioning valve to proportionally reduce in another predetermined ratio the fluid pressure applied to one of said brake and said one proportioning valve wherein the reduced fluid pressure acting on the downstream one of said one and other proportioning valve is a function of the product of said first named and other ratios.

Claim 38

A brake system comprising a brake, fluid pressure generating means for applying fluid pressure to said brake to effect energization thereof, and a pair of proportioning valves connected in said system in series flow relation between said generating means and said brake and operable generally to perform proportioning operations on the applied fluid pressure in said system under preselected conditions, respectively, one of said proportioning valves being responsive to the fluid pressure applied thereto in excess of a predetermined value from one of said generating means and the other of said proportioning valves to proportionally reduce in a predetermined ratio the fluid pressure applied to one of said brake and said other proportioning valve, and said other proportioning valve being responsive to the fluid pressure applied thereto in excess of another predetermined value from one of said generating means and said one proportioning valve to proportionally reduce in another predetermined ratio the fluid pressure applied to one of said brake and said one proportioning valve wherein the reduced fluid pressure acting on the downstream one of said one and other proportioning valve is a function of the product of said first named and other ratios.

Claim 39

A brake system comprising a brake, means for applying fluid pressure to said brake to effect energization thereof, and other means for controlling the application of the fluid pressure from said first named means to said brake including a pressure fluid flow passage connected between said first named means and said brake, and a pair of proportioning valves movable in said flow passage in series flow relation and operable generally in response to applied fluid pressure immediately upstream thereof in excess of one and other different predetermined values in said flow passage to perform proportioning operations thereon and establish reduced fluid pressures immediately downstream thereof in one and other predetermined ratios with the fluid pressures immediately upstream thereof, respectively, wherein the reduced fluid pressure acting on the downstream one of said proportioning valves is a function of the product of the one and other ratios.

Claim 40

A brake system comprising a brake, means for applying fluid pressure to said brake to effect energization thereof, and other means for controlling the application of the fluid pressure from said first named means to said brake including a pressure fluid flow passage connected between said first named means and said brake, and a pair of proportioning valves movable in said flow passage in series flow relation and operable generally in response to applied fluid pressure immediately upstream thereof in excess of one and other different predetermined values in said flow passage to perform proportioning operations thereon and establish reduced fluid pressures immediately downstream thereof in one and other predetermined ratios with the fluid pressures immediately upstream thereof, respectively, wherein the reduced fluid pressure acting on the downstream one of said proportioning valves is a function of the product of the one and other ratios.

Claim 41

A fluid pressure system comprising at least one brake, means for applying fluid pressure to said one brake to effect energization thereof, and other means for controlling the fluid pressure applied from said first named means to said one brake including a pair of sets of inlet and outlet chambers in series flow relation, the inlet chamber of one of said chamber sets being connected with said first named means and the outlet chamber of the other of said chamber sets being connected with said one brake, and a pair of proportioning valves between the inlet and outlet chambers of said one and other chamber sets for performing proportioning operations on the applied fluid pressure, said proportioning valves being responsive to the applied fluid pressure in excess of one and other predetermined values in the inlet chambers of said one and other chamber sets to proportionally reduce the applied fluid pressure in the outlet chambers of said one and other chamber sets in one and other predetermined ratios with the fluid pressures in excess of the one and other predetermined values in the inlet chambers of said one and other chamber sets, respectively, wherein the reduced fluid pressure in the outlet chamber of said other chamber set is a function of the product of the one and other ratios.

Claim 42

A fluid pressure system comprising at least one brake, means for applying fluid pressure to said one brake to effect energization thereof, and other means for controlling the fluid pressure applied from said first named means to said one brake including a pair of sets of inlet and outlet chambers in series flow relation, the inlet chamber of one of said chamber sets being connected with said first named means and the outlet chamber of the other of said chamber sets being connected with said one brake, and a pair of proportioning valves between the inlet and outlet chambers of said one and other chamber sets for performing proportioning operations on the applied fluid pressure, said proportioning valves being responsive to the applied fluid pressure in excess of one and other predetermined values in the inlet chambers of said one and other chamber sets to proportionally reduce the applied fluid pressure in the outlet chambers of said one and other chamber sets in one and other predetermined ratios with the fluid pressures in excess of the one and other predetermined values in the inlet chambers of said one and other chamber sets, respectively, wherein the reduced fluid pressure in the outlet chamber of said other chamber set is a function of the product of the one and other ratios.

Claim 43

A fluid pressure system according to claim 28, comprising means in said other means for connecting the inlet chamber of said other chamber set in pressure fluid communication with the outlet chamber of said one chamber set.

Claim 44

A control valve comprising a housing having a pressure fluid flow passage therethrough, a pair of proportioning valves movable in said flow passage in series flow relation for performing proportioning operations on the pressure fluid in said flow passage, said proportioning valves being operable generally in response to fluid pressures immediately upstream thereof in excess of one and other predetermined values to establish reduced fluid pressures immediately downstream thereof in one and other predetermined ratios with the fluid pressures immediately upstream thereof in excess of the one and other predetermined values, respectively, and the reduced fluid pressure acting on one of said proportioning valves having a continued and varying affect on the reduced output fluid pressure acting on the other of said proportioning valves wherein the reduced fluid pressure acting on the downstream one of said one and other proportioning valves is a function of the product of the one and other ratios.

Claim 45

A control valve comprising a housing having a pressure fluid flow passage therethrough, a pair of proportioning valves movable in said flow passage in series flow relation for performing proportioning operations on the pressure fluid in said flow passage, said proportioning valves being operable generally in response to fluid pressures immediately upstream thereof in excess of one and other predetermined values to establish reduced fluid pressures immediately downstream thereof in one and other predetermined ratios with the fluid pressures immediately upstream thereof in excess of the one and other predetermined values, respectively, and the reduced fluid pressure acting on one of said proportioning valves having a continued and varying affect on the reduced output fluid pressure acting on the other of said proportioning valves wherein the reduced fluid pressure acting on the downstream one of said one and other proportioning valves is a function of the product of the one and other ratios.