Alliedsignal Inc.

Daniel J Patient

Kenneth S Towers

Gary L Casey

Jack R Phipps

David F Scherer

Seth C Ravndal

Richard H Kolm

A vehicle powered by an electric motor which may be operated as a generator to effect regenerative braking of certain vehicle wheels in combination with individual friction brakes associated with other wheels. A commanded vehicle deceleration is apportioned among the wheels by determining the maximum regenerative braking deceleration achievable by drive wheels, and braking the vehicle occurs solely by regenerative braking so long as the commanded deceleration is less than the determined maximum deceleration. When a commanded deceleration exceeds the determined maximum, the regenerative braking is supplemented with friction braking of the other wheels while the maximum regenerative braking is maintained. The maximum regenerative braking of the certain wheels may be supplemented with additional friction braking of those same certain wheels, but this occurs only if the combined deceleration of the regenerative braking of the certain wheels and the friction braking of the other wheels is inadequate to achieve the commanded deceleration.

Maximized regenerative braking vehicle braking controller

A brake system (10) comprising: a master cylinder (20) including a primary (24) and a secondary (26) chamber and a reservoir (26); an accumulator (40), a pump (42) having first inlet port connected to a reservoir (26) of the master cylinder (20) and the second outlet port (b) connected to the accumulator (40), a motor (50) for selectively driving the pump as a function of system pressure, a pressure boost mechanism (60) connected to the accumulator (40) and the primary and secondary chambers of the master cylinder for generating a boosted pressure at a fixed multiple of the pressure in either the primary or secondary master cylinder chambers.

Electrohydraulic braking system with remote booster

In one embodiment the invention comprises a system (50; 200) for controlling service brake and parking functions of at least one wheel of a vehicle comprising: an electric motor (64) drivingly connected to a hydraulic pump (66) for pressurizing hydraulic fluid; the output of the pump communicated to at least one service brake (58a,b), comprising a first hydraulic cylinder (62a,b), an electronics circuit for controlling the speed of the motor (64) to regulate hydraulic pressure in the first hydraulic cylinder in response to operator braking activity (56, 64, 62), the motor and pump providing the primary means of service brake activation. The output of the pump is also communicated to a parking brake mechanism (30; 150), comprising a second hydraulic cylinder (34; 160), the parking brake mechanism having an activated mode of operation corresponding when the second hydraulic cylinder is unpressurized and a deactivated mode of operation corresponding when the second hydraulic cylinder is pressurized, and pressure control valves for controlling flow to and from the various hydraulic cylinders. A second variant of the system is disclosed in which only service brakes are electro-hydraulically controlled.

Electro-hydraulic service & parking brake system

A system and method of controlling pressure in a wheel brake cylinder of a brake. The hydraulic cylinder is connected to an electrically driven pump and a flow control valve is connected between the pump and the wheel cylinder. The system and method operate to control the speed of a motor driven pump to generate a desired pressure in a cylinder of the brake; generate a differential pressure, in the flow control valve, proportional to pump flow and communication same to a spring biased valving element; cause the valving element to move, in response to pressure forces acting on the valving element, generated by the pressure differential, and the force of the bias spring, so as to selectively open and close an associated exhaust port, connected to a drain or sump, such that in the steady state an equilibrium condition is achieved where the pressure forces balance the spring force and the pressure in the hydraulic cylinder is constant.

Direct acting electro-hydraulic braking system with regulated leak rate

A brake system (20) comprising: a master cylinder (26) and a pump (12) for selectively pressurizing an associated brake cylinder or cylinders; a motor (14) for powering the pump; a control circuit (16,90) for modulating motor speed in response to a signal indicative of desired braking effort and actual braking effort; and a control valve (30) responsive to master cylinder pressure for controlling pump flow and for permitting the decay of pressure in the brake cylinders.

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Sterling Heights, MI, United States of America

Daniel J Patient