Back to results
US 4,671,577 AGranted
Combined regenerative and friction braking system for a vehicle
AssigneeUrban Transportation Development Corporation Ltd.
InventorDavid H. Woods
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeUrban Transportation Development Corporation Ltd.
InventorDavid H. Woods
Estimating the term…
A vehicle supported for rolling movement on a track by a first set of wheels driven by an electric motor and a second unpowered set of wheels is provided with an improved braking system. The braking system includes a brake pedal which can be depressed to generate a brake demand signal, a regenerative braking system associated with the electric motor, and a friction braking system attached to the unpowered wheels. Control circuitry which regulates the operation of the two brake systems serves normally to actuate the regenerative braking system in response to the brake demand signal and to actuate the friction braking system only when the brake demand signal exceeds a predetermined level which corresponds normally to the maximum regenerative braking available. Under slippery rail conditions, a detector indicates slippage of the wheels relative to the rails during regenerative braking, and immediately actuates the friction braking system to produce additional braking in proportion to the brake demand signal. The braking system thus maximizes regeneration under optimal rail conditions and enhances braking under poor rail conditions.
A vehicle supported for rolling movement by a multiplicity of wheels including a first set of wheels driven by an electric motor and a second set of wheels, the vehicle having a braking system comprising:
In a transportation system including a track and a vehicle supported for rolling movement on the track, the vehicle including a first truck with a set of wheels driven by an electric motor and a second truck with a set of unpowered wheels, a braking system comprising:
Dependencies are inferred from the claim text.