KAMAZ vehicles and road trains are equipped with four independent brake systems: working, spare, parking and auxiliary
Although these systems have common elements, they work independently of each other, providing high braking performance in all operating conditions
In the future, we will designate these systems as working, spare, parking and auxiliary brakes.
In addition, KamAZ vehicles are equipped with an emergency brake release drive that provides the ability to move the car (road train) when it is automatically braked due to compressed air leakage, alarms and control devices that allow you to monitor the operation of the pneumatic drive.
The service brake is designed for service and emergency braking of the vehicle or its complete stop.
The service brake drive is pneumatic, dual-circuit, it actuates the brakes of the front axle and the rear bogie of the car separately.
The drive is controlled by a foot pedal mechanically connected to the brake valve.
The executive bodies of the service brake drive are the brake chambers on the wheels.
The spare brake is designed for service braking or stopping the car and road train; can be used both independently and in case of service brake failure.
The parking brake on KamAZ vehicles is made as a single unit with a spare one. To turn it on, the crane handle should be set to the extreme (upper) fixed position.
Thus, on KamAZ vehicles, the brake mechanisms of the rear bogie are common for service, spare and parking brakes.
The auxiliary brake of the vehicle is used to reduce the load and temperature of the brake mechanisms of the service brake.
The auxiliary brake on KamAZ vehicles is the engine retarder, when turned on, the engine intake pipes are blocked and the fuel supply is turned off.
The emergency release system is designed to release spring-loaded energy accumulators when they are automatically activated and stop the vehicle due to leakage of compressed air in the drive.
The drive of the emergency release system is duplicated: in addition to the pneumatic drive, there are mechanical release screws in each of the four spring-loaded energy accumulators, which makes it possible to turn them off mechanically.
The brake mechanism is designed to create artificial resistance to the rotation of the wheel in order to regulate its angular velocity or keep it stationary relative to the supporting surface.
All wheels of KamAZ vehicles are equipped with shoe brakes, which are characterized by high stability of braking properties.
The shoes are located inside the drums on fixed supports.
The brake mechanism (Fig. 1.) consists of a caliper 6, two shoes 3, rollers 4, axles 14, an expanding fist 7, a lever 9 with an adjusting mechanism and a drum 2.
The main components of the brake mechanism are mounted on a caliper 6, rigidly connected to the flange 12 of the bridge.
On the eccentric axles 14, fixed on the caliper, two brake pads 3 with friction linings 15 attached to them rest freely.
The latter are made according to the crescent profile in accordance with the nature of their wear.
The eccentric axles of the pads allow you to correctly center the pads with the brake drum when assembling the brake.
When braking, the pads are moved apart by an expanding fist and pressed against the inner surface of the drum, creating resistance to the rotation of the wheel.
To increase the efficiency of braking and reduce friction between the expanding fist and the pads, rollers 4 are installed. The pads are returned to their original position by four coupling springs 16.
The shaft of the expanding fist 7 rotates in the bracket on which the brake chamber 10 is installed.
A lever with a worm-type adjusting mechanism is attached to the end of the expander shaft, connected to the brake chamber rod.
The brake mechanisms of the front wheels differ from the brake mechanisms of the rear wheels by the design of the caliper, the body of the expanding fist and the expanding fist itself.