Braking systems

Claim 2

In a fluid-pressure vehicle brake system of the kind including a master piston exerting driver''s fluid pressure and a brake-actuating slave cylinder means responsive to said fluid pressure, the improvement of vehicle suspension means in which suspended loads create servo-braking pressure augmenting operator-generated braking pressure and including a vehiclesuspension element which is movable in response to the reaction force between a vehicle wheel and the ground occasioned by braking, a secondary servo piston arranged to generate servo pressure proportional to such reaction force in response to such movement, whereby such servo pressure is added to driver''s pressure when the servo pressure exceeds the driver''s pressure.

Claim 3

A system according to claim 1, constituted and arranged so that the driver''s pressure moves the servo piston in all relatively low-pressure brake applications, whereby the servo piston transmits such pressures to the slave cylinder means.

Claim 4

In a system according to claim 1 and further characterized by a resiliently resistant valve through which the driver''s pressure bypasses the servo piston in all relatively low-pressure brake applications and being movable when relatively high driver''s pressure is applied, thereby cutting driver''s pressure off from the slave cylinder means and conditioning the servo piston to apply the servo pressure in addition to the driver''s pressure.

Claim 5

In a system according to claim 3, and further characterized by a resiliently loaded one-way valve opening to permit flow from the master to the slave in non-normal conditions.

Claim 6

In a system according to claim 4, and further characterized by said resiliently resistant valve comprising a pressure-responsive speed valve which controls passage of driver''s pressure from master to slave without movement of the servo piston, and which spool valve is movable against resilience, so as to exert such control according to gauge driver''s pressure up to a value whereat such passage is cut off, whereupon the slave pressure is dependent n that which is generated by the servo piston as a measure of wheel drag.

Claim 7

In a system according to claim 5 in which the said spool valve is a piston like shuttle valve loaded by a spring and exposed so that atmospheric pressure acts with the spring in one sense of direction while the driver''s pressure acts in the opposite sense and is effective in terms of gauge pressure.

Claim 8

In a system according to claim 6 in which the servo piston is urged in the sense which is opposed to driver''s pressure by a spring.

Claim 9

In a fluid-pressure vehicle brake system of the kind including a master piston exerting driver''s fluid pressure which is transmitted to brake-actuating slave cylinder means, the improvement of vehicle suspension means in which suspended loads create servo-braking pressure augmenting operator-generated braking pressure and including a vehicle-suspension element bearing part of the weight of the vehicle and arranged to be movable in response to the drag of at least one vehicle wheel, said element being connected so as mechanically to move as a function of the drag, a servo piston in a servo cylinder through which the driver''s pressure is transmitted from master to slave with the servo piston intervening in the flow, the effect of the drag on the servo piston being such as to add such servo pressure to the driver''s pressure when there is generated a servo pressure between the servo piston and slave means greater than the driver''s pressure.

Claim 10

In a fluid-pressure vehicle brake system of the kind including a master piston exerting driver''s fluid pressure which is transmitted to brake-actuating slave cylinder means, the improvement of vehicle suspension means in which suspended loads create servo-braking pressure augmenting operator-generated braking pressure and including a vehicle-suspension element bearing part of the weight of the vehicle and arranged to be movable in response to the drag of at least one vehicle wheel, said element being connected so as mechanically to move as a function of the drag, a servo piston in a servo cylinder through which the driver''s pressure is transmitted from master to slave with the servo piston intervening in the flow, the effect of the drag on the servo piston being such as to add such servo pressure to the driver''s pressure when there is generated a servo pressure between the servo piston and slave means greater than the driver''s pressure.

Claim 11

In a system according to claim 8 in which the suspension element applies force to the servo piston as a function of the vertical load sustained by the element.