Anti-skid apparatus for wheels

Claim 2

Anti-skid apparatus for vehicle wheels comprising: a. a source of fluid under pressure; b. brake-applying means for exerting a braking force on the vehicle wheel according to the degree of fluid pressure supplied thereto; c. manually operable means interposed between said source of fluid under pressure and said brake-applying means for effecting supply of fluid pressure from said source to said brake-applying means at a selected degree; d. control means interposed between said manually operable means and said brake-applying means, said control means being operable to: i. a supply position in which fluid pressure from the source via the manually operable means may be supplied to the brakeapplying means at the selected degree; ii. a vent position in which fluid pressure supply to the brake-applying means is cut off and the degree of fluid pressure thereat is reduced, and iii. a cut-off position in which the brake-applying means is cut off from both supply and reduction of fluid pressure; e. wheel-slip detector means responsive to a predetermined wheel-slip threshold, to a predetermined partial restoration of the wheel to normal rotation, and to a complete restoration of the wheel to normal rotation for effecting operation of said control means to said vent, cut-off, and supply positions, respectively; and f. modulating means interposed between said manually operable means and said control means and comprising: i. a tapered throttle pin, ii. biasing means, iii. a piston member biased by said biasing means in one direction coaxially relative to said throttle pin toward a normal free-flow position, in which fluid pressure may flow unrestrictedly therethrough, and being operable in an opposite direction toward an initially established restricted flow position relative to the throttle pin in response to establishment of a pressure differential thereacross initiated at the onset of resumption of fluid pressure flow to the brake-applying means upon operation of said control means to its said supply position, said piston member having a concentric circular opening therein for accommodating Said throttle pin during such relative axial movement therebetween and cooperating with the throttle pin for providing a fluid pressure flow area variable in accordance with their respective positions relative to each other during restoration of fluid pressure to the brake-applying means, iv. said throttle pin being disposed such as to have the smallest diameter portion thereof positioned in said concentric opening in the free-flow position and to have the largerdiameter portion thereof positioned in said concentric opening in the restricted flow position, v. the initially established restricted-flow position being determined by the degree of fluid pressure prevailing at the brake-applying means at the onset of said resumption of fluid pressure flow thereto.

Claim 3

Anti-skid apparatus for vehicle wheels, as set forth in claim 1, wherein said throttle pin is characterized by an elongated paraboloidal shape with the largest diameter thereof being slightly smaller than the diameter of said concentric opening.

Claim 4

Anti-skid apparatus for vehicle wheels, as set forth in claim 1 wherein said flow rate control means comprises a casing in which said throttle pin is positionally fixed relative to the piston member.

Claim 5

Anti-skid apparatus for vehicle wheels comprising: a. a source of fluid under pressure; b. brake-applying means for exerting a braking force on the vehicle wheel according to the degree of fluid pressure supplied thereto; c. manually operable means interposed between said source of fluid under pressure and said brake-applying means for effecting supply of fluid pressure from said source to said brake-applying means at a selected degree; d. control means interposed between said manually operable means and said brake-applying means, said control means being operable to: i. a supply position in which fluid pressure from the source via the manually operable means may be supplied to the brake-applying means at the selected degree; ii. a vent position in which fluid pressure supply to the brake-applying means is cut off and the degree of fluid pressure thereat is reduced, and iii. a cut-off position in which the brake-applying means is cut off from both supply and reduction of fluid pressure; e. wheel-slip detector means responsive to a predetermined wheel-slip threshold, to a predetermined partial restoration of the wheel to normal rotation, and to a complete restoration of the wheel to normal rotation for effecting operation of said control means to said vent, cut-off, and supply positions, respectively; and f. modulating means interposed between said manually operable means and said control means and comprising: i. a casing, ii. an inner wall disposed in said casing and having a circular opening formed therein, iii. a piston operated throttle assembly including a piston member reciprocably disposed in said casing in axial alignment with said circular opening, and a tapered throttle member fixed to and extending coaxially from one side of said piston member through said circular opening, iv. biasing means for biasing said throttle assembly axially in one direction toward a free flow position, in which fluid pressure may flow unrestrictedly therethrough, and being operable in an axially opposite direction toward an initially established restricted flow position relative to said circular opening in response to establishment of a pressure differential thereacross initiated at the onset of resumption of fluid pressure flow to the brake-applying means upon operation of said control means to said supply position, v. said throttle member being so disposed as to have the smallest-diameter portion thereof positioned in said circular opening in the free-flow position of the throttle assembly and to have a larger-diameter portion thereof positioned in said circular opening in the restricted-flow position of the throttle assembly for providing a fluid pressure flow area variable in accordance with the axial poSition of the throttle assembly relative to the opening, vi. the initially established restricted-flow position being determined by the degree of fluid pressure prevailing at the brake-applying means at the onset of said resumption of fluid pressure flow thereto.

Claim 6

Anti-skid apparatus for vehicle wheels comprising: a. a source of fluid under pressure; b. brake-applying means for exerting a braking force on the vehicle wheel according to the degree of fluid pressure supplied thereto; c. manually operable means interposed between said source of fluid under pressure and said brake-applying means for effecting supply of fluid pressure from said source to said brake-applying means at a selected degree; d. control means interposed between said manually operable means and said brake-applying means, said control means being operable to: i. a supply position in which fluid pressure from the source via the manually operable means may be supplied to the brake-applying means at the selected degree; ii. a vent position in which fluid pressure supply to the brake-applying means is cut off and the degree of fluid pressure thereat is reduced, and iii. a cut-off position in which the brake-applying means is cut off from both supply and reduction of fluid pressure; e. wheel-slip detector means responsive to a predetermined wheel-slip threshold, to a predetermined partial restoration of the wheel to normal rotation, and to a complete restoration of the wheel to normal rotation for effecting operation of said control means to said vent, cut-off, and supply positions, respectively; and f. modulating means interposed between said manually operable means and said control means and comprising: i. a casing, ii. an inner wall disposed in said casing and having a circular opening formed therein, iii. a piston operated throttle assembly including a piston member reciprocably disposed in said casing in axial alignment with said circular opening, and a tapered throttle member fixed to and extending coaxially from one side of said piston member through said circular opening, iv. biasing means for biasing said throttle assembly axially in one direction toward a free flow position, in which fluid pressure may flow unrestrictedly therethrough, and being operable in an axially opposite direction toward an initially established restricted flow position relative to said circular opening in response to establishment of a pressure differential thereacross initiated at the onset of resumption of fluid pressure flow to the brake-applying means upon operation of said control means to said supply position, v. said throttle member being so disposed as to have the smallest-diameter portion thereof positioned in said circular opening in the free-flow position of the throttle assembly and to have a larger-diameter portion thereof positioned in said circular opening in the restricted-flow position of the throttle assembly for providing a fluid pressure flow area variable in accordance with the axial poSition of the throttle assembly relative to the opening, vi. the initially established restricted-flow position being determined by the degree of fluid pressure prevailing at the brake-applying means at the onset of said resumption of fluid pressure flow thereto.

Claim 7

Anti-skid apparatus for vehicle wheels, as set forth in claim 4, wherein said throttle member is substantially bellshaped with the smallest diameter end being affixed to one end of a stem fixed to said one side of said piston member.

Claim 8

Anti-skid apparatus for vehicle wheels comprising: a. a source of fluid under pressure; b. brake-applying means for exerting a braking force on the vehicle wheel according to the degree of fluid pressure supplied thereto; c. manually operable means interposed between said source of fluid under pressure and said brake-applying means for effecting supply of fluid pressure from said source to said brake-applying means at a selected degree; d. control means interposed between said manually operable means and said brake-applying means, said control means having: i. a supply position in which fluid pressure from the source via the manually operable means may be supplied to the brake-applying means at the selected degree, ii. a vent position in which fluid pressure supply to the brake-applying means is cut off and the degere of fluid pressure prevailing thereat is reduced, and iii. a cut-off position in which the brake-applying means is cut off from both supply and reduction of fluid pressure; e. wheel-slip detector means responsive to a predetermined wheel-slip threshold, to a predetermined partial restoration of the wheel to normal rotation, and to a complete restoration of the wheel to normal rotation for effecting operation of said control means to said vent, cut-off, and supply position, respectively; and f. modulating means coomprising: i. a casing; ii. a pair of independently operable throttle pistons disposed in said casing in axially parallel relation to each other, iii. one of said throttle pistons having a larger effective pressure area on one side than the effective pressure area of the corresponding side of the other throttle pistons and both pistons having equal effective pressure areas on the respective opposite sides thereof, iv. said one of said throttle pistons having restricted passage means formed therein for constantly communicating the opposite sides of both pistons with each other, v. each of said throttle pistons having a tubular valve member extending coaxially from said one side and said corresponding side, respectively, toward an end wall of said casing, said tubular valve members having respective coaxial passageways extending therethrough; and vi. a pair of springs for respectively biasing each of said throttle pistons independently in one direction toward respective free-flow positions in which fluid pressure may flow unrestrictedly between opposite sides of said pistons via said passageways, said pistons being operable in an opposite direction, in response to establishment of respective pressure differentials thereacross initiated at the onset of said resumption of fluid pressure flow to the brake-applying means, toward respective restricted-flow positions in which the free ends of said tubular valve members make abutting contact with said end wall for cutting off said free flow through said passageways and restricting flow of fluid pressure through said restricted passage means, vii. said pistons being restorable to their respective free flow positions upon equalization of fluid pressure on the opposite sides thereof in sequential order according to said effective pressure areas of said one side and said corresponding side of said pistons, respectively.

Claim 9

Anti-skid apparatus for vehicle wheels comprising: a. a source of fluid under pressure; b. brake-applying means for exerting a braking force on the vehicle wheel according to the degree of fluid pressure supplied thereto; c. manually operable means interposed between said source of fluid under pressure and said brake-applying means for effecting supply of fluid pressure from said source to said brake-applying means at a selected degree; d. control means interposed between said manually operable means and said brake-applying means, said control means having: i. a supply position in which fluid pressure from the source via the manually operable means may be supplied to the brake-applying means at the selected degree, ii. a vent position in which fluid pressure supply to the brake-applying means is cut off and the degere of fluid pressure prevailing thereat is reduced, and iii. a cut-off position in which the brake-applying means is cut off from both supply and reduction of fluid pressure; e. wheel-slip detector means responsive to a predetermined wheel-slip threshold, to a predetermined partial restoration of the wheel to normal rotation, and to a complete restoration of the wheel to normal rotation for effecting operation of said control means to said vent, cut-off, and supply position, respectively; and f. modulating means coomprising: i. a casing; ii. a pair of independently operable throttle pistons disposed in said casing in axially parallel relation to each other, iii. one of said throttle pistons having a larger effective pressure area on one side than the effective pressure area of the corresponding side of the other throttle pistons and both pistons having equal effective pressure areas on the respective opposite sides thereof, iv. said one of said throttle pistons having restricted passage means formed therein for constantly communicating the opposite sides of both pistons with each other, v. each of said throttle pistons having a tubular valve member extending coaxially from said one side and said corresponding side, respectively, toward an end wall of said casing, said tubular valve members having respective coaxial passageways extending therethrough; and vi. a pair of springs for respectively biasing each of said throttle pistons independently in one direction toward respective free-flow positions in which fluid pressure may flow unrestrictedly between opposite sides of said pistons via said passageways, said pistons being operable in an opposite direction, in response to establishment of respective pressure differentials thereacross initiated at the onset of said resumption of fluid pressure flow to the brake-applying means, toward respective restricted-flow positions in which the free ends of said tubular valve members make abutting contact with said end wall for cutting off said free flow through said passageways and restricting flow of fluid pressure through said restricted passage means, vii. said pistons being restorable to their respective free flow positions upon equalization of fluid pressure on the opposite sides thereof in sequential order according to said effective pressure areas of said one side and said corresponding side of said pistons, respectively.