Brake anti-lock mechanism

Claim 2

A control valve for an anti-lock brake system comprising a housing, relay means movable in said housing and operable generally in response to control fluid pressure subjected thereto to effect a metered application through said housing of fluid pressure supplied thereto, and means for controlling the control fluid pressure subjected to said relay means comprising an electric solenoid valve energized in response to a preselected condition to isolate the control fluid pressure acting on said relay means and vent the isolated control fluid pressure, said relay means being responsive to the reduction of the control fluid pressure upon the venting thereof to effect a proportional reduction of the applied fluid pressure.

Claim 3

A control valve for an anti-lock brake system comprising a housing, relay means movable in said housing and operable generally in response to control fluid pressure subjected thereto to effect a metered application through said housing of fluid pressure supplied thereto, and means for controlling the control fluid pressure subjected to said relay means comprising a first electric solenoid means energized in response to a preselected condition to isolate the control fluid pressure acting on said relay means, and a second electric solenoid means energized in response to another preselected condition to vent the isolated control fluid pressure, said relay means being responsive to the reduced magnitude of the isolated control fluid pressure upon the venting thereof to effect a corresponding proportional reduction in the magnitude of the applied fluid pressure.

Claim 4

A control valve for an anti-lock brake system comprising a housing, relay means movable in said housing and operable generally in response to control fluid pressure subjected thereto to effect a metered application through said housing of fluid pressure supplied thereto, and means for controlling the control fluid pressure subjected to said relay means comprising a first electric solenoid means energized in response to a preselected condition to isolate the control fluid pressure acting on said relay means, and a second electric solenoid means energized in response to another preselected condition to vent the isolated control fluid pressure, said relay means being responsive to the reduced magnitude of the isolated control fluid pressure upon the venting thereof to effect a corresponding proportional reduction in the magnitude of the applied fluid pressure.

Claim 5

A control valve for an anti-lock brake system comprising a housing, relay means movable in said housing and operable generally in response to control fluid pressure subjected thereto to effect a metered application through said housing of fluid pressure supplied thereto, and means for controlling the control fluid pressure selectively subjected to said relay means including means for isolating the control fluid pressure acting on said relay means upon the occurrence of a preselected condition, and other means for venting the isolated control fluid pressure upon the occurrence of another preselected condition, said relay means being responsive to the reduced magnitude of the isolated control fluid pressure upon the venting thereof to effect a corresponding proportional reduction in the magnitude of the applied fluid pressure, and a restricted flow passage in said housing for the flow therethrough of the control fluid pressure upon the subjection thereof to said relay means, said included means and other means defining at least a portion of said restricted passage.

Claim 6

A control valve for an anti-lock brake system comprising a housing, relay means movable in said housing and operable generally in response to control fluid pressure subjected thereto to effect a metered application through said housing of fluid pressure supplied thereto, and means for controlling the control fluid pressure selectively subjected to said relay means including means for isolating the control fluid pressure acting on said relay means upon the occurrence of a preselected condition, and other means for venting the isolated control fluid pressure upon the occurrence of another preselected condition, said relay means being responsive to the reduced magnitude of the isolated control fluid pressure upon the venting thereof to effect a corresponding proportional reduction in the magnitude of the applied fluid pressure, and a restricted flow passage in said housing for the flow therethrough of the control fluid pressure upon the subjection thereof to said relay means, said included means and other means defining at least a portion of said restricted passage.

Claim 7

A control valve according to claim 3, comprising means in said housing including another flow passage connected across said restricted flow passage in by-pass relation with said included means and said other means, the control fluid pressure acting on said relay means being exhausted through said other flow passage in response to a fluid pressure differential established between the magnitudes of the control fluid pressure acting on said relay means and that supplied to said restricted flow passage.

Claim 8

A control valve according to claim 4, wherein said last named means also includes uni-dirEctional valve means for controlling said other flow passage, said unidirectional valve means being normally urged toward a position closing said other flow passage and being movable toward an open position effecting the exhaustion of the control fluid pressure acting on said relay means in response to the fluid pressure differential established there-across between the magnitudes of the control fluid pressure acting on said relay means and that supplied to said restricted flow passage.

Claim 9

A control valve according to claim 2, wherein said first solenoid means also includes means for effecting venting of the isolated control fluid pressure upon the isolation thereof.

Claim 10

A control valve according to claim 2, wherein said first solenoid means is energized in response to the first named preselected condition to initially isolate the control fluid pressure acting on said relay means and thereafter effect venting of the isolated control fluid pressure.

Claim 11

A control valve according to claim 7, comprising a flow passage in said housing for the flow therethrough of the control fluid pressure upon the subjection thereof to said relay means, said first solenoid means defining with said housing at least a portion of said flow passage.

Claim 12

A control valve according to claim 8, comprising a first valve seat in said housing about said flow passage, and said first solenoid means comprising first valve means for engagement with said first valve seat, said first valve means being urged toward engagement with said first valve seat to close said flow passge and isolate the control fluid pressure acting on said relay means upon the energization of said first named solenoid means.

Claim 13

A control valve according to claim 9, comprising exhaust passage means in said housing and connected with said flow passage, a second valve seat in said housing about said exhaust passage means, said first solenoid means also comprising second valve means normally urged into engagement with said second valve seat closing said exhaust passage means, said second valve means being urged toward a position disengaged from said second valve seat to open said exhaust passage means and effect the venting of the isolated control fluid pressure upon the energization of said first solenoid means.

Claim 14

A control valve according to claim 10, comprising other exhaust passage means in said housing and connected with the control fluid pressure acting on said relay means, a third valve seat in said housing about said other exhaust passage means, said other solenoid means including third valve means normally urged into engagement with said third valve seat closing said other exhaust passage means, said third valve means being urged toward a position disengaged from said third valve seat to open said other exhaust passage means and effect further venting of the isolated control fluid pressure upon the energization of said other solenoid means.

Claim 15

A control valve according to claim 11, wherein said relay means defines with said housing a control chamber connected with said flow passage, other passage means in said housing connected between said control chamber and said flow passage in bypass relation therewith, the control fluid pressure in said control chamber being exhausted through said other passage means upon the exhaustion of the control fluid pressure subjected to said flow passage, a valve seat in said housing about said other passage means, and valve means being normally engaged with said valve seat to close said other passage means, said valve means being urged toward a position disengaged from said valve seat to open said other passage means and effect the exhausting passage therethrough of the control fluid pressure in response to a fluid pressure differential established across said valve means between the magnitudes of the control fluid pressure in said control chamber and that of the exhausting control fluid pressure subjected to said flow passage.

Claim 16

A control valve for an anti-lock brake systeM comprising a housing, relay means movable in said housing and defining therewith a control chamber, said relay means being operable generally in response to control fluid pressure in said chamber to effect the application and exhaustion of braking fluid pressure to and from said system, a control port in said housing for connection with supplied and exhausting flows of control fluid pressure, a flow passage in said housing connected between said control port and chamber, a pair of solenoid means in said housing for energization upon the occurrence of a pair of preselected conditions and defining at least portions of said restricted flow passage including a pair of exhaust valve means in said restricted flow passage and controlling the exhaustion of control fluid pressure therethrough from said control chamber, respectively, and one of said solenoid means including other valve means controlling the passage of the control fluid pressure through said restricted flow passage and connected for concerted movement with one of said exhaust valve means, said one solenoid means being energized upon the occurrence of one of said preselected conditions to urge said other valve means and one exhaust valve means toward positions in said restricted flow passage isolating the control fluid pressure in said control chamber from said control port and exhausting the isolated control fluid pressure from said control chamber, respectively, and the other of said solenoid means being thereafter energized upon the occurrence of the other of said preselected conditions to urge the other of said exhaust valve means toward a position in said restricted flow passage further exhausting the isolated control fluid pressure from said control chamber when said one solenoid is energized.

Claim 17

A control valve for an anti-lock brake systeM comprising a housing, relay means movable in said housing and defining therewith a control chamber, said relay means being operable generally in response to control fluid pressure in said chamber to effect the application and exhaustion of braking fluid pressure to and from said system, a control port in said housing for connection with supplied and exhausting flows of control fluid pressure, a flow passage in said housing connected between said control port and chamber, a pair of solenoid means in said housing for energization upon the occurrence of a pair of preselected conditions and defining at least portions of said restricted flow passage including a pair of exhaust valve means in said restricted flow passage and controlling the exhaustion of control fluid pressure therethrough from said control chamber, respectively, and one of said solenoid means including other valve means controlling the passage of the control fluid pressure through said restricted flow passage and connected for concerted movement with one of said exhaust valve means, said one solenoid means being energized upon the occurrence of one of said preselected conditions to urge said other valve means and one exhaust valve means toward positions in said restricted flow passage isolating the control fluid pressure in said control chamber from said control port and exhausting the isolated control fluid pressure from said control chamber, respectively, and the other of said solenoid means being thereafter energized upon the occurrence of the other of said preselected conditions to urge the other of said exhaust valve means toward a position in said restricted flow passage further exhausting the isolated control fluid pressure from said control chamber when said one solenoid is energized.

Claim 18

A control valve according to claim 13, comprising passage means in said housing connected between said control chamber and port in by-pass relation with said restricted flow passage, and check valve means controlling said passage means, said check valve means being normally urged toward a position closing said passage means and being movable toward a position opening said passage means to permit exhausting flow therethrough of the control fluid pressure from said control chamber in response to a pressure differential acting across said check valve means between the magnitudes of the control fluid pressure in said control chamber and the selective exhausting flow of the control fluid pressure at said control port.

Claim 19

A control valve according to claim 13, comprising a pair of exhaust passages in said housing, said exhaust valve means being normally urged toward positions in said housing closing said exhaust passages and being actuated toward positions in said housing opening said exhaust passages to effect the exhaustion of the isolated control fluid pressure upon the energization of said solenoid means, respectively.

Claim 20

A control valve according to claim 15, wherein one of said exhaust passages is predeterminately smaller than the other thereof.

Claim 21

A control valve according to claim 16, wherein said one exhaust passage is connected with said restricted flow passage between said other valve means and said control chamber, and the other of said exhaust passages is connected with said restricted flow passage between said one exhaust passage and said control chamber.

Claim 22

A control valve according to claim 16, comprising a pair of exhaust valve seats on said housing about said exhaust passages for engagement with said exhaust valve means, said exhaust valve means being normally urged into engagement with said exhaust valve seats to close said exhaust passages and being actuated toward positions disengaged from said valve seats to effect the exhaustion of the isolated control fluid pressure upon energization of said solenoid means, respectively.

Claim 23

A control valve according to claim 18, wherein said one solenoid means includes a pole piece supported in said housing, other passage means extending through said pole piece and defining a portion of said restricted flow passage, winding means in said housing about said pole piece for excitation upon the occurrence of said one preselected condition, armature means movable in said one solenoid means upon the excitation of said winding means, said armature means including said one exhaust valve means and said other valve means, a third valve seat on said pole piece about said other passage means for engagement with said other valve means, and spring means engaged with said armature means normally urging said one exhaust valve means into engagement with one of said exhaust valve seats and said other valve means toward a position disengaged from said third valve seat, said armature being movable against said spring means in response to the excitation of said winding means toward a position engaging said other valve means with said third valve seat to isolate the control fluid pressure in said control chamber and also disengaging said one exhaust valve means from said one exhaust valve seat to open said one exhaust passage and effect the exhaustion of the isolated control fluid pressure therethrough.

Claim 24

A control valve according to claim 19, comprising an inlet port in said housing adapted for connection with a source of braking fluid pressure, an outlet port in said housing adapted for connection with at least one brake of said system, an exhaust port in said housing for connection with said outlet port, fourth valve means movable in said housing and controlling pressure fluid communication between said inlet, outlet and exhaust ports, said relay means including a piston slidable in said housing and having opposed sides, one of said opposed sides being subjected to the control fluid pressure in said control chamber, extension means on the other of the opposed sides of said piston having a free end thereon for engagement with said fourth valve means, said piston being initially movable in response to the control fluid pressure in said control chamber acting on said one side thereof to engage said free end with said valve means interrupting pressure fluid communication between said outlet and exhaust ports and being thereafter further movable to concertedly move said valve means toward a position establishing metered pressure fluid communication between said inlet and outlet ports, the established fluid pressure at said outlet port acting on the other of the opposed sides of said piston in opposition to the control fluid pressure in said control chamber acting on said one opposed side.

Claim 25

A control valve for an anti-lock brake system comprising a housing, relay means movable in said housing for controlling said system and defining with said housing a chamber for control fluid pressure, said relay means being operable generally in response to control fluid pressure in said chamber to effect a metered application and exhaustion of braking fluid pressure to and from said system, a control port in said housing for selective connection with supplied and exhausting flow of control fluid pressure, a restricted passage in said housing connected between said control port and chamber, a pair of solenoid means in said housing adapted for energization upon the occurrence of different preselected conditions in said system and defining with said housing at least portions of said restricted flow passage, one of said solenoid means including valve means movable in said restricted flow passage and controlling the flow of control fluid pressure therethrough, said valve means being movable toward a position in said restricted flow passage isolating the control fluid pressure in said chamber from that at said control port upon the energization of said one solenoid means in response to the occurrence of one of said preselected conditions and the other of said solenoid means including other valve means movable in said restricted flow passage and controlling the exhaustion of control fluid pressure therefrom, said other valve means being movable toward a pOsition in said restricted flow passage exhausting isolated control fluid pressure therethrough from said chamber upon the energization of said other solenoid means in response to the occurrence of a different preselected condition only when said first named valve means is in its isolating position.

Claim 26

A control valve for an anti-lock brake system comprising a housing, relay means movable in said housing for controlling said system and defining with said housing a chamber for control fluid pressure, said relay means being operable generally in response to control fluid pressure in said chamber to effect a metered application and exhaustion of braking fluid pressure to and from said system, a control port in said housing for selective connection with supplied and exhausting flow of control fluid pressure, a restricted passage in said housing connected between said control port and chamber, a pair of solenoid means in said housing adapted for energization upon the occurrence of different preselected conditions in said system and defining with said housing at least portions of said restricted flow passage, one of said solenoid means including valve means movable in said restricted flow passage and controlling the flow of control fluid pressure therethrough, said valve means being movable toward a position in said restricted flow passage isolating the control fluid pressure in said chamber from that at said control port upon the energization of said one solenoid means in response to the occurrence of one of said preselected conditions and the other of said solenoid means including other valve means movable in said restricted flow passage and controlling the exhaustion of control fluid pressure therefrom, said other valve means being movable toward a pOsition in said restricted flow passage exhausting isolated control fluid pressure therethrough from said chamber upon the energization of said other solenoid means in response to the occurrence of a different preselected condition only when said first named valve means is in its isolating position.

Claim 27

A control valve according to claim 2, wherein said second solenoid means includes valve means movable toward a position to effect the venting of the isolated control fluid pressure upon the energization of said second solenoid means.

Claim 28

A control valve according to claim 2, comprising exhaust passage means in said housing and subjected to the isolated control fluid pressure, said second solenoid means normally closing said exhaust passage means.

Claim 29

A control valve according to claim 23, comprising a valve seat in said housing about said exhaust passage means, and said second solenoid means including valve means for engagement with said valve seat, said valve means being normally urged into engagement with said valve seat to close said exhaust passage means and said valve means being movable toward a position disengaged from said valve seat to open said exhaust passage means effecting the venting of the isolated control fluid pressure therethrough upon the energization of said second solenoid means.

Claim 30

A control valve according to claim 2, comprising exhaust passage means in said housing for communication with the isolated control fluid pressure, said first solenoid means normally closing said exhaust passage means.

Claim 31

A control valve according to claim 25, comprising a valve seat in said housing about said exhaust passage means, and said first solenoid means including valve means for engagement with said valve seat, said valve means being normally urged into engagement with said valve seat and being movable toward a position disengaged from said valve seat upon the energization of said first solenoid means.

Claim 32

A control valve according to claim 2, comprising first and second exhaust passage means in said housing for communication with the isolated control fluid pressure, first and second valve seats in said housing about said first and second exhaust passage means, said first and second solenoid means including first and second valve means engaged with said first and second valve seats to close said first and second exhaust passage means, and said first and second valve means being movable toward positions disengaged from said first and second valve seats upon the energization of said first and second solenoid means, respectively.

Claim 33

A control valve according to claim 27, comprising a flow passage in said housing for the flow therethrough of the control fluid pressure upon the subjection thereof to said relay means, a third valve seat in said housing about said flow passage, and third valve means on said first solenoid means for engagement with said third valve seat, said third valve means being movable into engagement with said third valve seat to isolate the control fluid pressure acting on said relay means.

Claim 34

A control valve according to claim 8, wherein said flow passage is restricted to predeterminately reduce the rate of flow of said control fluid pressure therethrough.

Claim 35

A control valve according to claim 11, wherein said first named and other exhaust passage means are restricted to predeterminately reduce the rate of venting flow of the isolated control fluid pressure therethrough, respectively.

Claim 36

A control valve according to claim 30, wherein one of said first named and other exhaust passage means is more restricted than the other thereof so that the rate of venting flow of the isolated control fluid pressure through said one of said first named and other exhaust passage means is predeterminately less than that through the other of said first named and other exhaust passage means.

Claim 37

A control valve according to claim 1, comprising exhaust passage means in said housing for communication with the isolated control flUid pressure, said solenoid valve normally closing said exhaust passage means.

Claim 38

A control valve according to claim 32, comprising a valve seat in said housing about said exhaust passage means, and said solenoid valve including valve means normally engaged with said valve seat to close said exhaust passage means and said valve means being movable toward a position disengaged from said valve seat to open said exhaust passage means venting the isolated control fluid pressure therethrough upon the energization of said solenoid valve.

Claim 39

A control valve according to claim 1, comprising a flow passage in said housing for the flow therethrough of the control fluid pressure upon the subjection thereof to said relay means, a valve seat in said housing about said flow passage, said solenoid valve including valve means for engagement with said valve seat, said valve means being movable into engagement with said valve seat to close said flow passage and isolate the control fluid pressure acting on said relay means upon the energization of said solenoid valve.

Claim 40

A control valve according to claim 34, comprising exhaust passage means in said housing for communication with the isolated control fluid pressure, another valve seat in said housing about said exhaust passage means, and said solenoid valve including other valve means for engagement with said other valve seat, said other valve means being movable toward a position disengaged from said other valve seat to vent th isolated control fluid pressure through said exhaust passage means upon the energization of said solenoid valve to engage said first named valve means with said first named valve seat.

Claim 41

A control valve for an anti-lock brake system comprising a housing having a control port therein, relay means movable in said housing and defining therewith a control chamber connected with said control port, said relay means being operable generally in response to control fluid pressure in said control chamber to effect the application through said housing of braking fluid pressure to said system, an exhaust port in said housing and connected with said control chamber, and an electric solenoid valve energized in response to a preselected condition for controlling pressure fluid communication between said control port and said control chamber and between said exhaust port and said control chamber, said solenoid valve being responsive to the occurrence of the preselected condition to interrupt pressure fluid communication between said control port and control chamber isolating the control fluid pressure therein acting on said relay means and also to establish pressure fluid communication between said exhaust port and said control chamber venting the isolated control fluid pressure in said chamber.

Claim 42

A control valve for an anti-lock brake system comprising a housing having a control port therein, relay means movable in said housing and defining therewith a control chamber connected with said control port, said relay means being operable generally in response to control fluid pressure in said control chamber to effect the application through said housing of braking fluid pressure to said system, an exhaust port in said housing and connected with said control chamber, and an electric solenoid valve energized in response to a preselected condition for controlling pressure fluid communication between said control port and said control chamber and between said exhaust port and said control chamber, said solenoid valve being responsive to the occurrence of the preselected condition to interrupt pressure fluid communication between said control port and control chamber isolating the control fluid pressure therein acting on said relay means and also to establish pressure fluid communication between said exhaust port and said control chamber venting the isolated control fluid pressure in said chamber.

Claim 43

A control valve according to claim 36, comprising first and second valve seats in said housing between said control port and control chamber and between said exhaust port and control chamber, respectively, said solenoid valve including valve means normally engaged with said second valve seat and disengaged from said first valve seat, said valve means being movable toward a position engaged with said first valve seat isolating the control fluid pressure in said control chamber and toward a position disengaged from said second valve seat to vent the isolated control fluid pressure in said control chamber to said exhaust port.

Claim 44

A control valve according to claim 36, comprising another exhaust port in said housing and connected with said control chamber, and another electric solenoid valve in said housing energized in response to another preselected condition for controlling pressure fluid communication between said other exhaust port and chamber, said other solenoid valve being energized upon the occurrence of the other preselected condition to also establish pressure fluid communication between said other exhaust port and said control chamber venting the isolated control fluid pressure in said chamber.

Claim 45

A control valve according to claim 38, comprising a third valve seat in said housing between said control chamber and said other exhaust ports, and said other solenoid valve including other valve means normally engaged with said third valve seat, said other valve means being movable toward a position disengaged from said third valve seat to establish the pressure fluid communication between said other exhaust port and said control chamber venting the isolated control fluid pressure in said control chamber upon the energization of said other solenoid valve.