Trailer brake with overrun control - has tractor brake acting on overrun linkage for normal braking

摘要

The overun control has a brake cylinder (10) mounted on the drawbar above the overun brake linkage and coupled to it by a sliding coupling with interlocking stops (8,9). The pressurised cylinder holds the brake in the off position so that when the tractor is braked the connection to the drawbar cylinder is vented to allow the spring loaded cylinder to pull up the overun brake. No separate brake connections are required between the tractor and the trailer. If the drawbar is pushed by the trailer the brakes are applied. If the tractor brake pressure fails then the brakes are again applied automatically.