In a very simple definition, the brake is the system that slows down or stops the vehicle in motion and stabilizes the parked vehicle. As a result of the command given by the driver with the brake pedal, a series of mechanisms are activated and provide the action called braking.
A motor vehicle has two brakes, a hand brake and a foot brake. The foot brake, that is, the brake pedal, is used to slow down or stop the vehicle in motion. The parking brake is also used to stabilize the stationary vehicle. In addition, after you take your foot off the gas, the vehicle will slow down and stop after a while. This is also called engine braking.
The mechanism that enables the vehicle to be stopped in a safe and controlled manner, which is found in many machines and all motor vehicles, is called brake.
What is a brake?
A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction.
There are two types of brakes in use: disc brakes and drum brakes. Disc brakes feature brake pads that press against a rotor when the brake pedal is applied. Drum brakes use brake shoes forced into the brake drum to bring the vehicle to a stop.
Most vehicles on the road today have brakes on all four wheels. Since the braking process shifts the vehicle’s weight forward, the brakes on the front of the vehicle do most of the work. Depending on your vehicle’s configuration, it may have disc brakes on all four wheels, or it could use disc brakes on the front and drum brakes on the rear.
How Do Brakes Work?
Just as your ankle bone is connected to your foot bone, your brake system relies on each connected brake part to function successfully—and safely.
Here’s a quick lesson: By pressing down on the brake pedal, you activate the cylinder that delivers brake fluid to the calipers that then engage your brake pads. Your brake pads then apply pressure to the rotors, creating the friction needed to stop your car. You see, it’s all connected.
All your brake parts work together to perform one important and crucial function: safe and precise stopping power.
Brakes In Motion:
- The brake pedal, when depressed, directly operates the master cylinder, located in the engine compartment (under the hood). It is connected to the brake booster.
- The brake booster, which is connected to the master cylinder by a pushrod, adds additional force to the master cylinder. The brake booster uses engine vacuum, by way of a vacuum hose and check valve.
- The master cylinder directs the brake fluid. It delivers brake fluid pressure to each of the four wheels through metal tubes and braided hoses. When the fluid pressure increases in the system, slave cylinders known as wheel cylinders and brake calipers are activated.
- When the brake calipers are activated, the disc pads compress against the brake discs or rotors, located inside the wheels of the vehicle. This compression causes friction and eventually slows the vehicle to a stop.
- When brake shoes are activated, they spread out against the brake drum, inside the wheels, causing friction what, too, slows the vehicle to a stop. Over time, pads, discs/rotors, shoes and drums become subject to wear.
Types of Car Brakes
Following are the different types of brakes:
- Disc Brakes
- Drum Brakes
- Emergency Brakes
- Anti-Lock Brakes
1. Disc Brakes
A disc brake is a type of brake that uses the calipers to squeeze pairs of pads against a disc or a rotor to create friction. There are two basic types of brake pad friction mechanisms: abrasive friction and adherent friction. This action slows the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hold it stationary. The energy of motion is converted into heat, which must be dispersed.
Hydraulically actuated disc brakes are the most commonly used mechanical device for slowing motor vehicles. The principles of a disc brake apply to almost any rotating shaft. The components include the disc, master cylinder, and caliper, which contain at least one cylinder and two brake pads on both sides of the rotating disc.
Related: What is Disc Brakes?
2. Drum Brakes
A drum brake is a type of brake that uses friction caused by a set of shoes or pads that press outward against a rotating bowl-shaped part called a brake drum.
The term drum brake usually means a brake in which shoes press on the inner surface of the drum. When shoes press on the outside of the drum, it is usually called a clasp brake.
Where the drum is pinched between two shoes, similar to a conventional disc brake, it is sometimes called a pinch drum brake, though such brakes are relatively rare. A related type called a band brake uses a flexible belt or “band” wrapping around the outside of a drum.
Related: What is Drum Brakes?
3. Emergency Brakes
Emergency brakes, also known as parking brakes, are secondary braking systems that work independently of the service brakes.
While there are many different kinds of emergency brakes (a stick lever between the driver and passenger, a third pedal, a push-button or handle near the steering column, etc.), almost all emergency brakes are powered by cables that mechanically apply pressure to the wheels.
They are generally used to keep a vehicle stationary while parked, but can also be used in emergencies if the stationary brakes fail.
4. Anti-Lock Brakes
ABS stands for Anti-lock Braking System, a key safety feature in most modern cars and trucks. Anti-lock brakes work with a car’s regular brake system by automatically pumping them in the event of a sudden stop.
When making a sudden stop, it is possible that one or more of your vehicle’s wheels could lock up, leaving you with little control of your vehicle. During wheel lock, the wheels of your vehicle stop rotating, causing your car to slide. For years, drivers were taught to pump the brakes when they felt their vehicle steering into a skid.
Today, ABS technology automates the brake pumping process so you can concentrate on steering the vehicle to safety during an emergency situation. By preventing your car’s wheels from locking, anti-lock brakes ensure that you can steer during a hard braking event.
In an anti-lock braking system, your car’s wheel speed is monitored and if wheel lock is detected, a sensor sends a message to a controller that releases and applies the brake up to 20 times per second, preventing a lock up and helping you maintain control of your vehicle.
In many of today’s newer cars and trucks, anti-lock brakes work in conjunction with other safety systems like traction control and electronic stability control to deliver a safer driving experience.
FAQs.
A good rule of thumb is to have your brakes checked whenever you rotate your tires-probably every six months. It’s a good idea for more aggressive drivers to check their brakes more frequently, with every oil change, for example.
Simply put, brake pads contact your rotors and cause friction to slow and stop your car. Brake pads are part of a very interconnected system, a system that relies on each of its parts to function safely and successfully.
Brake rotors in cars are circular metal discs connected to the wheels. There are four brake rotors installed in cars, one for each wheel. The rotors’ primary purpose is to slow down the turning of the car’s wheels by utilizing friction. The brake rotor process occurs when calipers squeeze your car’s brake pads together. The pads rub against the rotors’ surface areas, creating friction and eventually slowing down wheel rotation and your vehicle’s overall speed.
A caliper is part of the disc brake system, the type most cars have in their front brakes. The brake caliper houses your car’s brake pads and pistons. Its job is to slow the car’s wheels by creating friction with the brake rotors.
Brake hoses create a flexible connection between brake pipes and wheel brakes. They transmit the hydraulic pressure to the wheel cylinders and brake callipers. Brake hoses are usually made form a special inner and outer rubber with a multi-layer fabric insert in between.
