Text The Hydraulic Brake System

· Can you think of some vehicle without a braking system? Is it so necessary for the vehicle to have brakes? What is the main feature of the brake hydraulic system?

· Read the text and after answering the following questions render it:

1. What are the main components of the hydraulic brake system?

2. What a master cylinder is?

3. What is the main function of the hydraulic system?

 

Words and phrases (to be learnt by heart):

piston поршень

to undiminish не уменьшать, не ослаблять

resultant получающийся в результате; равнодействующий

to depress угнетать, понижать

master cylinder главный цилиндр

brake fluid тормозная жидкость

T-fitting крестовина

hose рукав; шланг; брандспойт

brake shoe тормозная колодка

brake drum тормозной цилиндр, тормозной барабан

to retard замедлять, тормозить, задерживать

to release выпускать, освобождать

disc brake дисковый тормоз

сaliper кронциркуль; нутромер; штангенциркуль

wheel cylinder рабочий тормозной цилиндр

split hydraulic system разделенная гидравлическая система

tandem master cylinder главный цилиндр, с двумя поршнями

pad прокладка, набивка, опора

rear задний, задняя сторона

leak утечка, течь

The hydraulic brake system used in the automobile is a multiple piston system. A multiple piston system allows forces to be transmitted to two or more pistons in the manner indicated in figure 1. Note that the pressure set up by the force applied to the input piston (1) is transmitted undiminished to both output pistons (2 and 3), and that the resultant force on each piston is proportional to its area. The multiplication of forces from the input piston to each output piston is the same as that explained earlier.

The hydraulic brake system from the master cylinders to the wheel cylinders on most automobiles operates in a way similar to the system illustrated in figure 2.

 

Figure 2.—Multiple piston system.

 

When the brake pedal is depressed, the pressure on the brake pedal moves the piston within the master cylinder, forcing the brake fluid from the master cylinder through the tubing and flexible hose to the wheel cylinders. The wheel cylinders contain two opposed output pistons, each of which is attached to a brake shoe fitted inside the brake drum. Each output piston pushes the attached brake shoe against the wall of the brake drum, thus retarding the rotation of the wheel. When pressure on the pedal is released, the springs on the brake shoes return the wheel cylinder pistons to their released positions. This action forces the displaced brake fluid back through the flexible hose and tubing to the master cylinder.

The force applied to the brake pedal produces a proportional force on each of the output pistons, which in turn apply the brake shoes frictionally to the turning wheels to retard rotation.

The hydraulic brake system on most automobiles operates in a similar way, as shown in figure 2.

 

Figure 2.—An automobile brake system.

 

(from http://www.tpub.com/fluid/ch1j.htm)

 

· Read the text and fill in the gaps using the words given below:

booster calipers distribution box pedal assembly

master cylinder brakes make hydraulics connections

fluid installation