Brake system

Claim 2

A fluid pressure system comprising a pair of brakes, a pair of fluid pressure sources, means for energizing said brakes in response to fluid pressure selectively applied thereto from one of said sources, a spring setting pressure released brake actuator connected with one of said brakes and operable in response to fluid pressure supplied thereto less than a predetermined value from the other of said sources to effect spring set energization of said one brake, and other means responsive to the fluid pressure less than the predetermined value supplied from said other source to said brake actuator for applying fluid pressure from said other source to the other of said brakes to also effect energization thereof.

Claim 3

A fluid pressure system comprising a pair of brakes, a pair of fluid pressure sources, first means responsive to fluid pressure selectively applied thereto from one of said sources for energizing at least one of said brakes, second means responsive to fluid pressure supplied thereto from the other of said sources less than a predetermined value for energizing the other of said brakes, and third means for applying fluid pressure from said other source to said first means to effect energization of said one brake in the event the supplied fluid pressure is reduced to a value less than the predetermined value.

Claim 4

A fluid pressure system comprising a pair of brakes, a pair of fluid pressure sources, first means responsive to fluid pressure selectively applied thereto from one of said sources for energizing at least one of said brakes, second means responsive to fluid pressure supplied thereto from the other of said sources less than a predetermined value for energizing the other of said brakes, and third means for applying fluid pressure from said other source to said first means to effect energization of said one brake in the event the supplied fluid pressure is reduced to a value less than the predetermined value.

Claim 5

A fluid pressure system comprising a pair of brakes, a pair of motors for energizing said brakes, a pair of fluid pressure sources, a spring setting pressure released brake actuator connected with one of said brakes, means for applying fluid pressure from said sources to said motors effecting energization of said brakes and to said brake actuator, respectively, and for venting the fluid pressure applied to said brake actuator to the atmosphere under preselected conditions, said brake actuator being responsive to the fluid pressure applied thereto less than a predetermined value to effect spring set energization of one of said brakes, and other means for applying fluid pressure from one of said sources to one of said motors to energize the other of said brakes in response to the reduction of the fluid pressure applied to said brake actuator to a value less than the predetermined value.

Claim 6

A fluid pressure system comprising a pair of brakes, a pair of motors for energizing said brakes, a pair of fluid pressure sources, a spring setting pressure released brake actuator connected with one of said brakes, means for applying fluid pressure from said sources to said motors effecting energization of said brakes and to said brake actuator, respectively, and for venting the fluid pressure applied to said brake actuator to the atmosphere under preselected conditions, said brake actuator being responsive to the fluid pressure applied thereto less than a predetermined value to effect spring set energization of one of said brakes, and other means for applying fluid pressure from one of said sources to one of said motors to energize the other of said brakes in response to the reduction of the fluid pressure applied to said brake actuator to a value less than the predetermined value.

Claim 7

A fluid pressure system according to claim 3, wherein said other means includes application means controlling pressure fluid communication between said one source and said one motor, said application means being movable in response to fluid pressure applied to said brake actuator less than the predetermined value toward an operative position communicating said one source and said one motor.

Claim 8

A fluid pressure system comprising a pair of brakes, a pair of motors for energizing said brakes, a pair of fluid pressure sources, a spring setting pressure released brake actuator connected with one of said brakes, means for applying fluid pressure from said sources to said motors effecting energization of said brakes and to said brake actuator, respectively, and for venting the fluid pressure applied to said brake actuator to the atmosphere under preselected conditions, said brake actuatOr being responsive to the fluid pressure applied thereto less than a predetermined value to effect spring set energization of one of said brakes, other means for applying fluid pressure from one of said sources to one of said motors to energize the other of said brakes in response to the reduction of the fluid pressure applied to said brake actuator to a value less than the predetermined value, said other means including application means controlling pressure fluid communication between said one source and said one motor, said application means being movable in response to fluid pressure applied to said brake actuator less than the predetermined value toward an operative position communicating said one source and said one motor, and said application means including resiliently urged means, an area on said resiliently urged means subjected to the fluid pressure applied to said brake actuator, said resiliently urged means being movable against its one force in response to the fluid pressure applied to said brake actuator in excess of the predetermined value acting on said area toward an inoperative position isolating said one source from said one brake and being movable toward its operative position in the event the fluid pressure applied to said brake actuator and acting on said area is reduced to a value less than the predetermined value.

Claim 9

A fluid pressure system comprising a pair of brakes, a pair of motors for energizing said brakes, a pair of fluid pressure sources, a spring setting pressure released brake actuator connected with one of said brakes, means for applying fluid pressure from said sources to said motors effecting energization of said brakes and to said brake actuator, respectively, and for venting the fluid pressure applied to said brake actuator to the atmosphere under preselected conditions, said brake actuatOr being responsive to the fluid pressure applied thereto less than a predetermined value to effect spring set energization of one of said brakes, other means for applying fluid pressure from one of said sources to one of said motors to energize the other of said brakes in response to the reduction of the fluid pressure applied to said brake actuator to a value less than the predetermined value, said other means including application means controlling pressure fluid communication between said one source and said one motor, said application means being movable in response to fluid pressure applied to said brake actuator less than the predetermined value toward an operative position communicating said one source and said one motor, and said application means including resiliently urged means, an area on said resiliently urged means subjected to the fluid pressure applied to said brake actuator, said resiliently urged means being movable against its one force in response to the fluid pressure applied to said brake actuator in excess of the predetermined value acting on said area toward an inoperative position isolating said one source from said one brake and being movable toward its operative position in the event the fluid pressure applied to said brake actuator and acting on said area is reduced to a value less than the predetermined value.

Claim 10

A fluid pressure system according to claim 5, wherein said resiliently urged means includes piston means, said area being on said piston means, and spring means urging said piston means toward the operative position thereof.

Claim 11

A fluid pressure system according to claim 5, comprising another area on said resiliently urged means additive to said first named area and subjected to the fluid pressure applied from said one source to said one motor.

Claim 12

A fluid pressure system according to claim 7, wherein said first named area is predeterminately greater than said other area.

Claim 13

A fluid pressure system according to claim 7, wherein said application means includes resiliently urged means, an area on said resiliently urged means subjected to the supplied fluid pressure, said resiliently urged means being movable in response to its own force toward the operative position in said flow passage when the supplied fluid pressure acting on said area is less than the predetermined value.

Claim 14

A fluid pressure system according to claim 9, wherein said resiliently urged means includes piston means, said area being on said piston means, and spring means urging said piston means toward its operative position.

Claim 15

A fluid pressure system according to claim 10, wherein said piston means is movable toward an inoperative position against said spring means in response to the supplied fluid pressure in excess of the predetermined value acting on said area, valve means for engagement with said piston means controlling said flow passage, said piston means being movable in response to said spring means when the supplied fluid pressure acting on said area is less than the predetermined value toward the operative position to engage and actuate said valve means and effect the application through said flow passage of the fluid pressure from said other source to said first means.

Claim 16

A fluid pressure system according to claim 10, wherein said third means includes a valve seat about said flow passage, said valve means being urged into engagement with said valve seat to close said flow passage when said piston means is in its inoperative position, said valve means being actuated by said piston means upon the movement thereof toward the operative position and disengaged from said valve seat.

Claim 17

A fluid pressure system comprising a pair of brakes, a pair of fluid pressure sources, first means responsive to fluid pressure selectively applied thereto from one of said sources for energizing at least one of said brakes, second means responsive to fluid pressure supplied thereto from the other of said sources less than a predetermined value for energizing the otHer of said brakes, third means for applying fluid pressure from said other source to said first means to effect energization of said one brake in the event the supplied fluid pressure is reduced to a value less than the predetermined value, said third means including a pressure fluid flow passage connected between said other source and said first means, and application means for controlling said flow passage, said application means being movable in response to the supplied fluid pressure less than the predetermined value toward an operative position in said flow passage effecting the application therethrough of the fluid pressure from said other source to said first means.

Claim 18

A fluid pressure system comprising a pair of brakes, a pair of fluid pressure sources, first means responsive to fluid pressure selectively applied thereto from one of said sources for energizing at least one of said brakes, second means responsive to fluid pressure supplied thereto from the other of said sources less than a predetermined value for energizing the otHer of said brakes, third means for applying fluid pressure from said other source to said first means to effect energization of said one brake in the event the supplied fluid pressure is reduced to a value less than the predetermined value, said third means including a pressure fluid flow passage connected between said other source and said first means, and application means for controlling said flow passage, said application means being movable in response to the supplied fluid pressure less than the predetermined value toward an operative position in said flow passage effecting the application therethrough of the fluid pressure from said other source to said first means.

Claim 19

A fluid pressure system according to claim 13, comprising valve means controlling said flow passage, said valve means being actuated by said application means upon the movement thereof to its operative position to effect the application through said flow passage of the fluid pressure from said other source to said first named means.

Claim 20

A fluid pressure system according to claim 11, wherein said third means includes a valve seat about said flow passage, said valve means being normaly urged into engagement with said valve seat to close said flow passage and interrupt pressure fluid communication between said other source and said first means, said valve means being disengaged from said valve seat to establish the pressure fluid communication between said other source and said first means upon the actuation of said valve means by said application means.

Claim 21

A fluid pressure system comprising a pair of brakes, a source of service pressure, a source of emergency pressure, a pair of service motors connected with said brakes, a spring setting pressure released brake actuator also connected with one of said brakes, an operator actuated application valve having service and emergency portions respectively connected with said service and emergency pressure sources including first means in said service portion selectively movable upon operator actuation of said application valve to effect the application of service pressure from the source thereof to said service motors for energizing said brakes, and second means in said emergency portion normally applying emergency fluid pressure from the source thereof to said brake actuator and movable to isolate said emergency pressure source from said brake actuator and vent the emergency pressure from said brake actuator to the atmosphere under preselected conditions, said brake actuator being responsive to the reduction of the emergency pressure therefrom to a predetermined value to effect spring set energization of said one brake, an emergency brake valve including a housing, a flow passage in said housing connected between said emergency pressure source and one of said service motors, valve means controlling said flow passage, a chamber in said housing connected with the emergency fluid pressure supplied to said actuator and separate from said flow passage, a valve actuating member movable in said chamber including a stem portion extending into said flow passage for operative engagement with said valve means, spring means engaged with said valve actuating member and opposing fluid pressure expansion of said chamber, an area on said valve actuating member subjected to the emergency fluid pressure in said chamber, said valve actuating member being movable against the force of said spring means in response to the emergency fluid pressure on said chamber in excess of a predetermined value acting on said area and said valve actuating member also being movable in response to the force of said spring means when the emergency fluid pressure in said chamber acting on said area is reduced to a value less than the predetermined value to engage said stem portion with said valve means and move said valve means toward a position in said flow passage effecting the application therethrough of the emergency pressure from the source thereof to said one service motor for energizing the other of said brakes, and another area on said stem portion in said flow passage additive to said first named area and subjected to the emergency pressure applied therethrough to said one service motor to oppose the force of said spring means.

Claim 22

A fluid pressure system comprising a pair of brakes, a source of service pressure, a source of emergency pressure, a pair of service motors connected with said brakes, a spring setting pressure released brake actuator also connected with one of said brakes, an operator actuated application valve having service and emergency portions respectively connected with said service and emergency pressure sources including first means in said service portion selectively movable upon operator actuation of said application valve to effect the application of service pressure from the source thereof to said service motors for energizing said brakes, and second means in said emergency portion normally applying emergency fluid pressure from the source thereof to said brake actuator and movable to isolate said emergency pressure source from said brake actuator and vent the emergency pressure from said brake actuator to the atmosphere under preselected conditions, said brake actuator being responsive to the reduction of the emergency pressure therefrom to a predetermined value to effect spring set energization of said one brake, an emergency brake valve including a housing, a flow passage in said housing connected between said emergency pressure source and one of said service motors, valve means controlling said flow passage, a chamber in said housing connected with the emergency fluid pressure supplied to said actuator and separate from said flow passage, a valve actuating member movable in said chamber including a stem portion extending into said flow passage for operative engagement with said valve means, spring means engaged with said valve actuating member and opposing fluid pressure expansion of said chamber, an area on said valve actuating member subjected to the emergency fluid pressure in said chamber, said valve actuating member being movable against the force of said spring means in response to the emergency fluid pressure on said chamber in excess of a predetermined value acting on said area and said valve actuating member also being movable in response to the force of said spring means when the emergency fluid pressure in said chamber acting on said area is reduced to a value less than the predetermined value to engage said stem portion with said valve means and move said valve means toward a position in said flow passage effecting the application therethrough of the emergency pressure from the source thereof to said one service motor for energizing the other of said brakes, and another area on said stem portion in said flow passage additive to said first named area and subjected to the emergency pressure applied therethrough to said one service motor to oppose the force of said spring means.