Brakes-Mechanical

Mechanical brakes are a third style which are used almost exclusively in Europe. A few trailers using this system have recently been imported to the U.S. These brakes operate much like those used on older automobiles. Figure 3.36 illustrates the mechanics of the system. It is basically a surge or inertia style of brake at the coupler, relying on compression forces between trailer and tow-car for actuation. According to technical information received from AL-KO, a brake rod connects to the compensator which transfers the longitudinal motion into horizontal motion through the Bowdry cable. As this cable is pulled, one shoe is pushed against the drum which in turn activates the second shoe and the friction from the two then acts to slow the rotation. Exposure of cables to the elements can eventually result in some dragging and a less responsive stopping.

Thus the cables should be checked and cleaned often to ensure a reliable braking system. One might want to note that the automotive industry abandoned mechanical brakes many years ago in favor of hydraulic brakes which have proven themselves to provide more efficient braking. In general, though, other than the disadvantages associated with any surge system, this style of brake is clean and trim while being easy to inspect and maintain. Europeans also seem to feel this braking system is superior since it is purely mechanical and there is no fluid to “top up.” Also, due to its mechanical aspects, mechanical braking systems have relatively long term reliability, even if their efficiency is not as great.