The leading shoe is “dragged” into the friction surface of drum brake design pdf drum and thus achieving greater braking force. The other shoe is “trailing”, moving against the direction of rotation, is thrown away from the friction surface of the drum and is far less effective.
When the vehicle is moving in reverse, the role of the leading and trailing shoes is switched. What would be the leading shoe when the vehicle is travelling forwards becomes the trailing shoe, and vice versa. The car’s handbrake typically operates only the rear wheels, and when the vehicle is stationary on a slope prior to a hill start, the rear SLS brakes are essential in arresting any rearward motion. Classic Mini’s made by Austin and Morris were fitted with single leading shoe drum brakes from 1959-1964.
This page was last edited on 6 December 2017, at 10:48. Unsourced material may be challenged and removed. Several schemes of operation of the drum brake, in black is highlighted the distribution force during the braking phase. In the first drum brakes, levers and rods or cables operated the shoes mechanically. Some designs have two wheel cylinders. As the shoes in drum brakes wear, brakes required regular manual adjustment until the introduction of self-adjusting drum brakes in the 1950s. This spelled the beginning of the crossover of drum brakes to disc brakes in passenger cars.