Brake pads are a key element of road safety. It is with their help that the kinetic energy of a moving car is converted into thermal energy, which is accompanied by deceleration and stopping. Their operating principle is based on the high friction force that occurs when the friction material of the pads is pressed against the brake disc. This technology is extremely simple and at the same time allows you to effectively slow down the car, increases the reliability of the entire system and simplifies maintenance.
What are car brake pads
The brake pad is a replaceable part of the caliper. It looks like a metal plate with a friction lining on it. The part is directly involved in slowing down the speed of transport. There are two types of pads:
- For disc brake system;
- For drum brake system.
Depending on the modification of the brakes, the pads either compress the disc or rest against the walls of the drum. Cars can use different types of braking systems. Often there are options when the contours of the line into which the brake fluid is pumped are divided into front and rear.
In such cars, when you press the brake pedal, the front calipers are activated first, and then the rear ones. For this reason, drum pads are replaced less frequently than front pads.
In addition to the key classification, these products differ from each other in functionality:
- The kit may also include a wear sensor, which is connected to the vehicle's on-board electrical system. Since the pads in any car are subject to wear, the sensor notifies the driver of the need to replace the part.
- The brake element has a mechanical wear indicator. A characteristic creaking noise allows the driver to determine that the elements are worn out and need to be replaced. This type of pads has a lower cost compared to the previous modification.
If the car uses a combined braking system, then the front element in this case will be disc, and the rear element will be drum. This type of system is installed on budget cars. A more expensive car is equipped with all-round disc brakes.
Story
The first brake pads were made of wood and came into contact with the brake discs through special levers. Such brake pads were also installed on horse-drawn carriages. It should be taken into account that at some time such braking systems were not in great demand, and this happened at a time when car manufacturers installed engines that did not have much power in their cars. Therefore, the cars were light in weight and did not require good brakes.
Of course, progress does not stand still, and more and more powerful engines are being produced every day, so brake systems and stopping shoes are being modernized. At a time when disc brakes were unpopular, cars were stopped using drum brakes.
What affects braking?
The car stops due to the action of the pad on the disc mounted on the wheel hub. The friction coefficient of the replacement pad plays a key role in this. Naturally, the higher the friction, the more clearly the brakes will operate.
In addition to system response and braking efficiency, this characteristic directly affects the effort that the driver must apply to the brake pedal in order for the vehicle to begin to slow down.
The value of the friction coefficient is influenced by the material from which the friction surface is made. This determines whether the brakes will be soft and precise or whether the pedal will need to be pressed hard so that the wheels slow down.
Summary
Today, almost every resident has a car. About half of drivers know the structure of their car and will be able to repair it if it breaks down. In addition, many people know the weight of their car, based on which they can select spare parts designed for a certain weight.
There are many elements in the machine that need to be installed, based on the weight of the machine. Such devices include shock absorbers, springs and other suspension elements.
Weight also needs to be taken into account when choosing rear or front brake pads. Once you choose rear or front brake pads, they need to be installed correctly on your vehicle to function properly.
Types of brake pads
As mentioned earlier, all pads are divided into two types: for installation in drums (rear wheels, and in older cars they were installed in the front) or on discs (front wheels or in a more expensive model of vehicle - in a circle).
The peculiarity of the drum brake system is that the design of the mechanism allows the use of a large contact area to increase the friction force during brake activation. This modification is more effective on trucks, since the truck is often heavy, and disc brakes in this case will have too small a contact surface.
To increase efficiency, it will be necessary to install an additional support, which is not economically profitable. The advantage of this modification is that the vehicle manufacturer can freely increase the width of the drum and pads, which will increase the reliability of the brakes. The disadvantages of drum vehicles are that they are poorly ventilated, which is why they can overheat during a long descent. Also, the drum can wear out faster, since all the debris resulting from the wear of the pad remains inside the mechanism.
As for the disc modification, the pads and disc in them are better ventilated, and the entry of dirt and moisture into such brakes is not critical for transport. The disadvantage of this modification is that the contact area can be increased by installing a disk with an increased diameter, and, accordingly, larger calipers. This is a disadvantage, since not every wheel allows such an upgrade.
The effectiveness of the pads depends on the friction lining. For this, manufacturers use different materials. Here is their main classification.
Organic brake pads
The friction layer of such parts includes various materials of organic origin. It can be rubber mixed with glass, fiberglass, carbon compounds, etc. Such elements have a minimum content of metal components (no more than 20 percent).
