Automatic Brake Force Regulator

The brake system of both passenger cars and trucks consists of a number of nodes. One of the important components is the brake force regulator. Not all motorists know how this element works and is arranged. But if it is defective, there can be an unpleasant surprise for the driver in case of emergency braking. Motorists call this component of the braking system a "sorcerer". This name was given to this site because his work was very mysterious and unpredictable. Let's try to understand the device, the principle of operation and adjustment of this regulator.

The main task of regulators and the physics of inhibition

The grip of the wheel of a car with the road surface, like the friction force, is proportional to the vertical loads. The coefficient of proportionality is the coefficient of the level of adhesion of the tire to the road. From a person, this value does not depend. It can be determined based on the condition of the road and car tires. The higher the grip of the wheel with the asphalt surface during braking, the shorter the stopping distance. And since the action of the pads on the car also acts as inertia, then there is a redistribution of the vertical load on the wheels. Therefore, the force of the impact on the disk must be uneven. The brake force regulator is also used to improve braking performance when the machine is not loaded. In this case, the clutch force will be completely different than in the case of a loaded car.

Where is the brake force regulator on the WHA

In many domestic cars, the "sorcerer" is located in the rear of the body. It should be noted that the brake force regulator (VAZ 2170 including) is not installed on those models that are equipped with the ABS system. If we consider modern models of AvtoVAZ production, namely Priory, Grant and Kalina, then the regulator is located on the left side of the bottom. When it comes to older models of AvtoVAZ, the brake force regulator can be found on the right rear of the bottom. These are cars VAZ 2101-2107.

How does the braking force regulator work during braking

When the driver sharply presses the pedal, the rear part of the body will rise, the front part - on the contrary, will lower. And at that moment the braking force regulator begins its work. After the device works, it will immediately allow the rear wheels to start to decrease speed immediately after pressing the pedal. The fact is that if the wheels on the rear axle of the car start braking at the same moment with the front axle, then there is a high probability of skidding. If the wheels on the rear axle begin to slow down later than the front, then the risk of skidding is reduced to almost zero. When the car brakes, then the distance between the bottom and the rear beam increases. As this gap grows, the lever releases the regulator piston and, thanks to this, the main line with liquid is closed, which is suitable for the rear wheels. As a result, they will not be blocked, but will continue to rotate.

Brake force regulator device

It is fixed on the body bracket and is connected on passenger cars with a beam of the rear axle on the pull rod and torsion bar. The second end of the last element acts on the piston of the regulator. The regulator input is connected to the master cylinder, and the output to the rear brake cylinder . The device is driven by a drive connected to the rear beam. As for the design, the brake force regulator consists of a body divided into several cavities (usually two). One of them is connected to the main cylinder, the other to the rear system. Also there are pistons and valves, through which the access to the brake fluid is blocked . At the time of starting work, her pressure in the two chambers is the same. However, in the first, the liquid acts on a smaller portion of the piston, while in the second it acts on a larger section. The piston tends to move, but can not do this because of the centering spring. If the pressure in the master cylinder begins to increase, then the piston can easily overcome the force of the spring, so that the valve will block the access of the liquid. This is the classic principle of the braking force regulator. Today there are hydraulic elements, pneumatic, with electronic control.

Trucks and braking force regulator

An automatic regulator is installed on the KamAZ car. It performs almost the same tasks as the device in passenger cars. It automatically controls and distributes the force of the pads on the rear axle wheels, depending on how the axle load on the wheels changes. It also helps to speed up their unlocking. The effect of this regulator is based on changing the air pressure in the chambers of the system at the rear of the trailer, depending on the axial loads when the speed decreases. Brake force regulator "KamAZ" is installed on the frame. The lever and thrust through the elastic part, as well as the rod, connects with the bridge beams and the rear wheeled cart in such a way that distortions and twisting during the operation of the system will not affect the braking force. The resilient element is necessary to protect the regulating device from various damages during vertical displacements of the rear axles. It also significantly reduces vibration and absorbs shocks when driving on uneven roads.

The device regulator on cars "KamAZ"

This unit consists of a valve, a valve tappet together with a drive. Also in the device there is a piston with an inclined edge. There is also a membrane that is in connection with the piston. Inside the case there are connecting tubes. In the latter, the air flows under the piston, so that the smooth operation of the system is ensured at the moment of shutting off the valve. The regulator channels are attached to the top of the crane, and the second channel is connected to the brake chambers on the rear wheels. The third conclusion works with the atmosphere. When the car slows down, the air coming from the top of the brake valve to the first channel of the regulator shifts the piston down, and the other side is compressed to the stop. The valve is pressed against the seat of the pusher and the second channel is more connected to the atmosphere at this moment. Then further movement of the piston will lead to the opening of the valve. Air from the first channel will go to the second, and then - to the brake chambers. Virtually the same device and the principle of operation has a regulator MAZ braking forces.

Devices from Wabco

Wabco produces spare parts for trucks. Among a huge range of products, there are also parts for brake systems. In the company's catalog you can find everything you need to repair trucks. One of the devices that produces this brand is the Wabco braking force regulator. It is suitable for installation not only for trucks, but also for trailers of various models and brands. Many truck owners appreciated the quality of the equipment and parts from this manufacturer. The quality of the controller is much better than the standard device. It is installed on the factory fittings.

How to check "sorcerer"

On the example of the car VAZ 2110, you can see how the brake force regulator is checked. Symptoms are few. This is the withdrawal of the machine to the side, frequent failures in the skid, insufficiently effective braking. At VAZ 2100 RTS is located on the left under the bottom in the area of the rear wheels. All operations with him are best done by lifting the car to the lift, installing it on the flyover or observation pit. The main defects of the device can be easily detected visually. If fluid flows are observed, the cuff is likely to be worn or damaged. If the piston of the regulator is in one position and does not want to move, then most likely it is sour. This defect can be determined through visual diagnostics. If these problems appear, repairs will not help here. Solve the situation can only replace. Many replace the simple regulator with a crane-regulator of braking forces. This system is considered more convenient. If the element is completely clean, there is a small gap between the actuating lever and the plate, the rod perfectly moves to both sides when the pedal is pressed, then the mechanism is fully functional and nothing needs to be done with it.

How to regulate RTS

If you take cars VAZ, the adjustment of the brake force regulator depends heavily on the body position. The adjustment must be carried out not only during each maintenance, but also when replacing the suspension parts - springs or shock absorbers, after repair work on the rear beam and when replacing it. To adjust the car must be put on the flyover. This is done not only for convenience of work, but also for installing the suspension in an equilibrium position. In this state, when you press your hands on the trunk, the car will swing two or three times. So, for adjustment, you first need to loosen the fasteners to the bracket. It is necessary to achieve a gap of 2 mm between the elastic plate, which rests against the rod and lever. This is done by moving the mechanism. It should be borne in mind that in the process it is necessary to overcome the resistance of the spring. They are large enough, so it is recommended to use a special tool or other suitable device. Then the bolts are tightened and check the gaps with a feeler gauge. If there is no such tool, then a 2 mm diameter drill or a suitable coin can be used.

Running tests

About whether the adjustment is good, you can understand only on the go. It should accelerate to 40 km / h, and then press the pedal, and in the process of braking to assess how the car behaves. You should not be "toss" forward. With high-quality adjustment, both parts of the car are heeled minimally.