Operating systems for trailer brakes

Claim 1

Operating system for trailer brakes adapted to regulate the effect of the brakes of the trailer vehicle in dependence on changes in load occurring on the coupling unit between tractor and trailor vehicles as a result of differences in relative speed between said vehicles comprising: tractor and trailer coupling means connected to each other forming a substantially rigid coupling unit, transmitter means sensing pressure and pull connected in said coupling unit activated by even small changes in relative positions of said coupling means, amplifier means responsive to pressure and pull on said transmitter means including a pair of input differentially connected transistors, a pair of complementarily connected transistors connected to said first-mentioned pair of transistors, diode bridge networks connected preceding the input of said first-mentioned transistors and following the output of said second-mentioned transistors, and damper means to prevent oscillations in the tractor-trailer unit; power source to the brakes connected to and controller by said amplifier means, and brake light circuit means connected in such system of above-mentioned means to operate said system when said circuit means is closed.

Claim 7

A method of controlling the operation of trailer brakes to regulate the effect of the brakes of the trailer vehicle in dependence on changes in load occurring on the coupling unit between tractor and trailer vehicles as a result of differences in relative speed between said vehicles which comprises: moving the tractor and trailer coupling means in its pressure and pull directions relative to each other proportional to forces acting on said coupling means during changes in relative speed, sensing changes proportional to the magnitude and direction of the pressure and pull on the coupling means allowed by the elasticity of the coupling means, amplifying the changes sensed, applying initial braking power to the brakes irrespective of the changes sensed, controlling the power to the brakes in accordance with the changes sensed, and closing a brake light circuit means to initiate the performance of the above-mentioned steps.

Claim 8

A method of controlling the operation of trailer brakes to regulate the effect of the brakes of the trailer vehicle in dependence on changes in load occurring on the coupling unit between tractor and trailer vehicles as a result of differences in relative speed between said vehicles which comprises: moving the tractor and trailer coupling means in its pressure and pull directions relative to each other proportional to forces acting on said coupling means during changes in relative speed, sensing changes proportional to the magnitude and direction of the pressure and pull on the coupling means allowed by the elasticity of the coupling means, amplifying the changes sensed, applying initial braking power to the brakes irrespective of the changes sensed, controlling the power to the brakes in accordance with the changes sensed, and closing a brake light circuit means to initiate the performance of the above-mentioned steps.