Electronic device for controlling the brakes of a vehicle

Claim 1

A device for controlling the brakes of a pulled vehicle towed by a pulling vehicle, said device comprising a current source, a control switch connected to said current source, magnetic transducers mounted on one of said vehicles and spaced along a line parallel to the longitudinal axis of said one vehicle and connected to said current source through said control switch, said transducers producing an output signal, said transducers being magneto-resistances interconnected in two arms of a four-arm diagonal bridge having the current source connected to one diagonal, a signal treating means including the other two arms and the other diagonal of said bridge for receiving said output signal, said signal treating means controlling said brakes, setting means to balance said bridge, a magnetic inertia block, spring means for mounting said block on said one vehicle between said transducers for movement substantially parallel to the longitudinal axis of said one vehicle so that said block moves into closer proximity to one of said transducers and farther from the other of said transducers to unbalance the bridge and to modify at least one electric characteristic of said output signal in response to deceleration of said one vehicle to give an output signal substantially proportional to the instantaneous deceleration of a vehicle to control the brakes of a pulled vehicle.

Claim 2

A device for controlling the brakes of a pulled vehicle towed by a pulling vehicle, said device comprising a current source, a control switch connected to said current source, magnetic transducers mounted on one of said vehicles and spaced along a line parallel to the longitudinal axis of said one vehicle and connected to said current source through said control switch, said transducers producing an output signal, said transducers being magneto-resistances interconnected in two arms of a four-arm diagonal bridge having the current source connected to one diagonal, a signal treating means including the other two arms and the other diagonal of said bridge for receiving said output signal, said signal treating means controlling said brakes, setting means to balance said bridge, a magnetic inertia block, spring means for mounting said block on said one vehicle between said transducers for movement substantially parallel to the longitudinal axis of said one vehicle so that said block moves into closer proximity to one of said transducers and farther from the other of said transducers to unbalance the bridge and to modify at least one electric characteristic of said output signal in response to deceleration of said one vehicle to give an output signal substantially proportional to the instantaneous deceleration of a vehicle to control the brakes of a pulled vehicle.