Based on the provided information, back brakes are often called drum brakes, as these are most frequently used on the rear axle of today's vehicles.
Drum brakes are a common type of braking system found on the rear wheels of many cars and often on trailers. Unlike disc brakes which use calipers and pads to squeeze a rotor, drum brakes utilize a different mechanism to create friction and slow the wheel.
Understanding Drum Brakes
According to the reference, drum brakes are the system most often employed on the rear axle. This design choice is prevalent in modern vehicles and trailers.
A key characteristic of drum brakes is that they do not use brake pads as the friction material. This distinguishes them significantly from disc brake systems, which are commonly found on the front axle and sometimes on the rear as well.
How Drum Brakes Function
The mechanics of a drum brake system involve several key components working together inside a hollow drum that spins with the wheel.
Here's a breakdown of the process based on the provided information:
- The system includes a wheel cylinder.
- Inside the wheel cylinder are pistons.
- When the brake pedal is applied, hydraulic pressure causes the pistons to extend.
- These pistons push brake shoes outwards.
- The brake shoes press against the inside of a spinning drum.
- This contact creates friction, slowing the drum and, consequently, the wheel.
Essentially, the friction is generated by the outward force of the brake shoes rubbing against the inner surface of the rotating drum.
Where Drum Brakes Are Used
As highlighted in the reference:
- They are most often used on the rear axle of modern vehicles.
- They are also very common on trailers.
This makes drum brakes a familiar sight when examining the braking systems of many vehicles from the rear.