Spring bushing activated brake proportioner

Abstract From the Canadian patent

An improved braking system particularly for a vehicle such as a van, subject, to relatively large differences in loading including a force responsive proportioning valve inserted between a master brake cylinder and the rear brakes for increasing the rear braking effort relative to the front as the load on the vehicle increases. A position follower device operably connected to the force input of the proportioning valve is responsive to angular movements of the end portion of the rear leaf spring which transmits an increasing input force to the valve as the vehicle load increases.