Dynamic skid control with the torque equilibrium concept

Claim 2

In a vehicular skid control system, a first sensor and a second sensor to sense the rotational speed of the driven and the undriven wheels of the vehicle, a speed departure valve operatively connected to said sensors and having a first valve element movable in response to differences in the rotational speed of the driven and undriven wheels, and a brake lockout valve controlling a second valve element normally positioned in an equilibrium position, but movable upon movement of the speed departure valve element in response to overspeeding of the driven wheels to apply a braking force to brake motor means of said driven wheels, whereupon the speed of the driven wheels is controlled as a function of optimum road tire interface torque.

Claim 3

In a vehicular braking and skid control system, a first set of wheels which are undriven and having brake motor means and having a first hydraulic sensor for developing a first sensing signal corresponding to the rotational speed of the undriven wheels, a second set of wheels which are driven having brake motor means and having a second hydraulic sensor for developing a second sensing signal corresponding to the rotational speed of the driven wheels, hydraulic circuit means for selectively transmitting braking forces to said brake motor means, and means for controlling the speed of the driving wheel comprising, a speed departure valve comprising a movable spool having a control annulus in said hydraulic circuit means and having motive surfaces on opposite sides thereof receiving the signals from said hydraulic sensors, the speed departure valve annulus being closed by said signals upon overspeeding of the driven wheels and the closing of the annulus interrupting part of the hydraulic circuit means to apply braking forces to said driven wheels, whereupon the speed of the driven wheels is controlled as a function of optimum road tire interface torque.

Claim 4

In a vehicular braking and skid control system, a first set of wheels which are undriven and having brake motor means and having a first hydraulic sensor for developing a first sensing signal corresponding to the rotational speed of the undriven wheels, a second set of wheels which are driven having brake motor means and having a second hydraulic sensor for developing a second sensing signal corresponding to the rotational speed of the driven wheels, hydraulic circuit means for selectively transmitting braking forces to said brake motor means, and means for controlling the speed of the driving wheel comprising, a speed departure valve comprising a movable spool having a control annulus in said hydraulic circuit means and having motive surfaces on opposite sides thereof receiving the signals from said hydraulic sensors, the speed departure valve annulus being closed by said signals upon overspeeding of the driven wheels and the closing of the annulus interrupting part of the hydraulic circuit means to apply braking forces to said driven wheels, whereupon the speed of the driven wheels is controlled as a function of optimum road tire interface torque.

Claim 5

a brake lock-out valve actuated whenever said speed departure valve is operated, said dynamic proportioning valve being regulated by said brake lock-out valve to release the front wheels whenever said brake lock-out valve is actuated.

Claim 6

a brake lock-out valve actuated whenever said speed departure valve is operated, said dynamic proportioning valve being regulated by said brake lock-out valve to release the front wheels whenever said brake lock-out valve is actuated.

Claim 7

a brake lock-out valve actuated whenever said speed departure valve is operated, said slip control valve having a spool and acted on by pressure passing through said brake lock-out valve, thereby moving the slip control valve to lock out the up and down valve and release the undriven wheels so that the speed of the driven wheels will be controlled as a function of the optimal road tire interface torque.

Claim 8

a brake lock-out valve actuated whenever said speed departure valve is operated, said slip control valve having a spool and acted on by pressure passing through said brake lock-out valve, thereby moving the slip control valve to lock out the up and down valve and release the undriven wheels so that the speed of the driven wheels will be controlled as a function of the optimal road tire interface torque.

Claim 9

a brake lock-out valve actuated whenever said speed departure valve is operated, said dynamic pressure control means including means regulated by said brake lock-out valve to release the undriven wheels.

Claim 10

a brake lock-out valve actuated whenever said speed departure valve is operated, said dynamic pressure control means including means regulated by said brake lock-out valve to release the undriven wheels.

Claim 11

a brake lockout valve actuated whenever said speed departure valve is operated in response to differences in the rotational speed of the wheels, said proportioning valve having a spool and acted on by pressure passing through said brake lockout valve, thereby moving the proportioning valve to lock out the up and down valve and release the undriven wheels.

Claim 12

a brake lockout valve actuated whenever said speed departure valve is operated in response to differences in the rotational speed of the wheels, said proportioning valve having a spool and acted on by pressure passing through said brake lockout valve, thereby moving the proportioning valve to lock out the up and down valve and release the undriven wheels.

Claim 13

In a vehicular braking and skid control system, a first set of wheels which are undriven and having brake motor means and having a first hydraulic sensor for developing a first sensing signal corresponding to the rotational speed of the undriven wheels, a second set of wheels which are driven having brake motor means and having a second hydraulic sensor for developing a second sensing signal corresponding to the rotational speed of the driven wheels, hydraulic circuit means for selectively transmitting braking forces to said brake motor means on the driven and undriven wheels, and means for controlling the speed of the driving wheels comprising, a speed departure valve comprising a movable spool having a control annulus in said hydraulic circuit means and having a mode of surfaces on opposite sides thereof receiving the signals from said hydraulic sensors to correspondingly adjust the operation of the hydraulic circuit means, and a brake lockout valve in said hydraulic circuit means operable to lock out the actuation of the brake motor means on the undriven set of wheels whenever the speed departure valve is actuated, thereby automatically braking the driven wheels at critical phases in the vehicle''s operation when an impending skid is sensed.

Claim 14

In a vehicular braking and skid control system, a first set of wheels which are undriven and having brake motor means and having a first hydraulic sensor for developing a first sensing signal corresponding to the rotational speed of the undriven wheels, a second set of wheels which are driven having brake motor means and having a second hydraulic sensor for developing a second sensing signal corresponding to the rotational speed of the driven wheels, hydraulic circuit means for selectively transmitting braking forces to said brake motor means on the driven and undriven wheels, and means for controlling the speed of the driving wheels comprising, a speed departure valve comprising a movable spool having a control annulus in said hydraulic circuit means and having a mode of surfaces on opposite sides thereof receiving the signals from said hydraulic sensors to correspondingly adjust the operation of the hydraulic circuit means, and a brake lockout valve in said hydraulic circuit means operable to lock out the actuation of the brake motor means on the undriven set of wheels whenever the speed departure valve is actuated, thereby automatically braking the driven wheels at critical phases in the vehicle''s operation when an impending skid is sensed.

Claim 15

A vehicular skid control and power braking system comprising, a skid control pump driven as a fUnction of rotational wheel speed of the vehicle, a power steering pump driven independently of the vehicle wheel speed, a full power system unit receiving the output of said pumps and including hydraulic circuit means to selectively utilize the dynamically pressurized fluid so furnished for braking purposes, said full power system comprising an operator-actuated master cylinder having first and second master cylinder portions, an up and down valve having a piston actuated by the pressure developed in the first master cylinder portion and transmitting pressure therethrough, a first brake motor means for a set of undriven wheels and receiving pressure from said first master cylinder portion, a second brake motor means for a set of driven wheels receiving pressure from said second master cylinder portion, said up and down valve having piston and cylinder means receiving the dynamically pressurized fluid from the power steering pump, a proportioning valve connected in series with said up and down valve, a first hydraulic sensor for developing a first sensing signal corresponding to the speed of the undriven wheels of the vehicle, a second hydraulic sensor for developing a second sensing signal corresponding to the speed of the driven wheels of the vehicle, said proportioning valve receiving signals from both of said sensors to proportion the braking force applied to the driven and undriven wheels of the vehicle, and a pair of additional valves to control the speed of the driving wheels as a function of the optimal road tire interface torque, comprising,

Claim 16

A vehicular skid control and power braking system comprising, a skid control pump driven as a fUnction of rotational wheel speed of the vehicle, a power steering pump driven independently of the vehicle wheel speed, a full power system unit receiving the output of said pumps and including hydraulic circuit means to selectively utilize the dynamically pressurized fluid so furnished for braking purposes, said full power system comprising an operator-actuated master cylinder having first and second master cylinder portions, an up and down valve having a piston actuated by the pressure developed in the first master cylinder portion and transmitting pressure therethrough, a first brake motor means for a set of undriven wheels and receiving pressure from said first master cylinder portion, a second brake motor means for a set of driven wheels receiving pressure from said second master cylinder portion, said up and down valve having piston and cylinder means receiving the dynamically pressurized fluid from the power steering pump, a proportioning valve connected in series with said up and down valve, a first hydraulic sensor for developing a first sensing signal corresponding to the speed of the undriven wheels of the vehicle, a second hydraulic sensor for developing a second sensing signal corresponding to the speed of the driven wheels of the vehicle, said proportioning valve receiving signals from both of said sensors to proportion the braking force applied to the driven and undriven wheels of the vehicle, and a pair of additional valves to control the speed of the driving wheels as a function of the optimal road tire interface torque, comprising,

Claim 17

A skid controller for a vehicle having two sets of wheels including front wheels and rear wheels each having their own brake motors and comprising, a means for measuring rear wheel speed, a means for measuring front wheel speed, an external power means for supplying pressure to separate front and rear brake actuating motors, and dynamic pressure control means responsive to differences in front and rear wheel speeds, thereby to apply more or less pressure to the front brake actuating motors to maintain an optimum relationship of front-to-rear wheel slip, one set of said wheels being driven wheels and the other being undriven wheels, and a pair of additional valves to control the speed of the driven wheels as a function of the optimal road tire interface torque, comprising,

Claim 18

A skid controller for a vehicle having two sets of wheels including front wheels and rear wheels each having their own brake motors and comprising, a means for measuring rear wheel speed, a means for measuring front wheel speed, an external power means for supplying pressure to separate front and rear brake actuating motors, and dynamic pressure control means responsive to differences in front and rear wheel speeds, thereby to apply more or less pressure to the front brake actuating motors to maintain an optimum relationship of front-to-rear wheel slip, one set of said wheels being driven wheels and the other being undriven wheels, and a pair of additional valves to control the speed of the driven wheels as a function of the optimal road tire interface torque, comprising,

Claim 19

An hydraulic power brake system with skid control comprising, separate front and rear braking motors for a wheeled vehicle, a skid control pump rotational as a function of the rotational speed of the rear wheels, a second pump operable as a power source, a master cylinder booster for actuation by the vehicle operator when braking is desired, a front wheel sensor rotatable as a function of the rotational speed of the front wheels, a rear wheel sensor rotatable as a function of the rotational speed of the rear wheels, one set of said wheels being driven wheels and the other being undriven wheels and a dynamic proportioning means for maintaining a relationship in front-to-rear wheel slip comprising, and uP-down valve having a differential area piston formed with a first set of smaller piston areas and a second set of larger piston areas, means for applying master cylinder static pressure to one of said smaller piston areas whereby the other of said smaller piston areas will transmit corresponding pressure to the front wheel braking motors, means for transmitting pressure from said power source to said larger piston areas, a slip control valve comprising a spool having a pair of spool sections which when open will vent a corresponding one of said larger piston areas to drain so no pressure registers thereon, and means for applying a signal generated by said skid control pump to one end of said spool and for applying a signal generated by said front wheel sensor to the other end of said spool, whereby the net signal operating on said spool will position the spool to raise and lower the dynamic pressure loading of said differential area piston, and a pair of additional valves to control the speed of the driven wheels, comprising,

Claim 20

An hydraulic power brake system with skid control comprising, separate front and rear braking motors for a wheeled vehicle, a skid control pump rotational as a function of the rotational speed of the rear wheels, a second pump operable as a power source, a master cylinder booster for actuation by the vehicle operator when braking is desired, a front wheel sensor rotatable as a function of the rotational speed of the front wheels, a rear wheel sensor rotatable as a function of the rotational speed of the rear wheels, one set of said wheels being driven wheels and the other being undriven wheels and a dynamic proportioning means for maintaining a relationship in front-to-rear wheel slip comprising, and uP-down valve having a differential area piston formed with a first set of smaller piston areas and a second set of larger piston areas, means for applying master cylinder static pressure to one of said smaller piston areas whereby the other of said smaller piston areas will transmit corresponding pressure to the front wheel braking motors, means for transmitting pressure from said power source to said larger piston areas, a slip control valve comprising a spool having a pair of spool sections which when open will vent a corresponding one of said larger piston areas to drain so no pressure registers thereon, and means for applying a signal generated by said skid control pump to one end of said spool and for applying a signal generated by said front wheel sensor to the other end of said spool, whereby the net signal operating on said spool will position the spool to raise and lower the dynamic pressure loading of said differential area piston, and a pair of additional valves to control the speed of the driven wheels, comprising,

Claim 21

For use in a wheeled vehicle skid controller, a dynamic proportioning valve having means for dynamically proportioning pressure to the front and rear braking motors of the wheeled vehicle, operator actuated means for supplying operator generated pressure to said valve, means for applying a rear wheel generated pressure signal to said valve, and means for applying a front wheel generated signal to said valve, whereby said valve will maintain an optimum relationship of front-torear wheel slip, and a pair of additional valves to control the speed of the rear wheels as a function of the optimal road tire interface torque, comprising,

Claim 22

For use in a wheeled vehicle skid controller, a dynamic proportioning valve having means for dynamically proportioning pressure to the front and rear braking motors of the wheeled vehicle, operator actuated means for supplying operator generated pressure to said valve, means for applying a rear wheel generated pressure signal to said valve, and means for applying a front wheel generated signal to said valve, whereby said valve will maintain an optimum relationship of front-torear wheel slip, and a pair of additional valves to control the speed of the rear wheels as a function of the optimal road tire interface torque, comprising,