Overrun brakes of trailers called overrun brakes.
Some trailers, especially used in agriculture, are equipped with mechanical brakes, called overrun brakes. The principle of their operation is this, that when the tractor brakes, the trailer's brakes are applied without any additional actions on the part of the driver. The brakes are applied via a lever system. When the vehicle is braked, the trailer, due to the inertia force, rests with the hitch rod against the vehicle hitch (tractor). This stick moves rearward and rotates the shaft. Rods are attached to the arms of this roller, which actuate the shoe brakes of the front wheels of the trailer. There are so-called. Roman nuts, which are used to adjust the length of the rods. Braking with the overrun brake is the stronger, the more rapidly the tractor brakes. To prevent braking of the trailer, the coupling rod is locked with a latch when the towed vehicle is backed up. The pawl prevents the bar from moving back and thus prevents the trailer brakes from being activated. The pawl should be disengaged while driving forward, which enables operation of the trailer brakes.