Control valve

Claim 2

A control valve for use in a dual hydraulic brake system having a separate hydraulic pressure supply for each system and having a proportioning valve for one of the systems with the proportioning valve being operable generally for reducing the pressure to that one system, said control valve comprising a housing for connection with the separate pressure supplies, passage means in said housing for connecting the one separate pressure supply in by-pass relation with said proportioning valve, other means for comparing the magnitudes of the pressures of the separate pressure supplies and movable in said housing from a normally centered position toward one of opposed translated positions in response to the pressure of the one pressure supply upon the failure of the other pressure supply, a valve seat in said housing about said passage means, and valve means defining a lost motion connection with said other means in its centered position and normally urged into engagement with said valve seat closing said passage means, said other means being movable to its one translated position through the lost motion connection to drivingly engage and thereafter concertedly move said valve means to a position disengaged from said valve seat opening said passage means for by-passing said proportioning valve to obviate the pressure reducing function thereof.

Claim 3

A control valve according to claim 1, comprising a spring means engaged with said valve means normally urging said valve means toward engagement with said valve seat.

Claim 4

A control valve according to claim 2, wherein said spring means is engaged between said valve means and said other means.

Claim 5

A control valve according to claim 2, wherein said valve means includes an annular sleeve member, opposed end walls on said sleeve member extending radially inward thereof, a valve element for engagement with said valve seat and connected with one of said end walls, aperture means in the other of said end walls, and retainer means on said sleeve member engaged with said spring means, said spring means normally urging said valve element into engagement with said valve seat, extension means on said other means extending through said aperture means into said sleeve member, and an abutment on said extension means for engagement with said other end wall and normally spaced therefrom defining the lost motion connection when said other means is in its centered position, said abutment means being initially movable through the lost motion connection relative to said other end wall into driving engagement therewith and being thereafter further movable to concertedly move said valve means and disengage said valve element from said valve seat to open said passage means upon the movement of said other means to its one translated position.

Claim 6

A control valve according to claim 1, comprising a pair of abutment means on said valve means and other means, respectively, and spaced from each other to define the lost motion connection when said other means is in its centered position, one of said abutment means being initially movable relative to the other of said abutment means into driving engagement therewith and being thereafter further movable to disengage said valve means from said valve seat opening said passage means upon the movement of said other means to its one translated position.

Claim 7

A control valve according to claim 5, comprising spring means engaged between said valve means and said other means urging said valve means into engagement with said valve seat when said other means is in its centered position and urging said other abutment means toward said one abutment means.

Claim 8

A control valve according to claim 1, wherein said valve means includes an annular sleeve member, opposed end walls on said sleeve member extending radially inwardly thereof, one of said end walls defining the lost motion connection for driving engagement with said other means, a valve element connected with the other of said end walls for engagement with said valve seat, and spring means engaged with said valve means urging said valve element into engagement with said valve seat, said valve element being disengaged from said valve seat upon the movement of said other means toward its one translated position through the lost motion connection into driving engagement with said one end wall.

Claim 9

A control valve for a dual fluid pressure brake system having a separate pressure supply for each system and means operable generally for modulating one of said systems to vary the pressure thereof under preselected conditions, and an electrical driver warning circuit having a switch therein generally operable for energizing said circuit, said control valve comprising a housing for connection with the separate pressure supplies, a switch actuating piston having opposed end portions respectively subjected to the pressures of the separate pressure supplies and movable in said housing from a normally centered position toward one of opposed translated positions in response to the pressure of one of the pressure supplies acting on one of said opposed end portions upon the failure of the pressure of the other of the pressure supplies, a passage in said housing adjacent to said one end portion for connecting the pressure of the one pressure supply in by-pass relation with said modulating means, a valve seat on said housing about said passage, extension means on said one end portion, valve means movable on said extension means for engagement with said valve seat, spring means engaged between said valve means and one end portion normally urging said valve means into engagement with said valve seat to close said passage when said switch actuating piston is in its centered position, first and second abutments on said extension means and valve means, respectively, and predeterminately spaced from each other to define a lost motion connection therebetween when said valve means is engaged with said valve seat and said switch actuating piston is in its centered position, said first abutment being initially movable through said lost motion connection into driving engagement with said second abutment and thereafter further movable to concertedly drive said valve means to a position disengaged from said valve seat opening said passage and by-passing said modulating means upon the movement of said switch actuating piston to its one translated position, and other means on said switch actuating piston for engagement with said switch to energize said circuit upon the movement of said switch actuating piston to its translated position.

Claim 10

A control valve for a dual fluid pressure brake system having a separate pressure supply for each system and means operable generally for modulating one of said systems to vary the pressure thereof under preselected conditions, and an electrical driver warning circuit having a switch therein generally operable for energizing said circuit, said control valve comprising a housing for connection with the separate pressure supplies, a switch actuating piston having opposed end portions respectively subjected to the pressures of the separate pressure supplies and movable in said housing from a normally centered position toward one of opposed translated positions in response to the pressure of one of the pressure supplies acting on one of said opposed end portions upon the failure of the pressure of the other of the pressure supplies, a passage in said housing adjacent to said one end portion for connecting the pressure of the one pressure supply in by-pass relation with said modulating means, a valve seat on said housing about said passage, extension means on said one end portion, valve means movable on said extension means for engagement with said valve seat, spring means engaged between said valve means and one end portion normally urging said valve means into engagement with said valve seat to close said passage when said switch actuating piston is in its centered position, first and second abutments on said extension means and valve means, respectively, and predeterminately spaced from each other to define a lost motion connection therebetween when said valve means is engaged with said valve seat and said switch actuating piston is in its centered position, said first abutment being initially movable through said lost motion connection into driving engagement with said second abutment and thereafter further movable to concertedly drive said valve means to a position disengaged from said valve seat opening said passage and by-passing said modulating means upon the movement of said switch actuating piston to its one translated position, and other means on said switch actuating piston for engagement with said switch to energize said circuit upon the movement of said switch actuating piston to its translated position.