When the car brakes, do all four wheels brake together?

When the car brakes, do all four wheels brake together?

Do the four wheels brake together when the car brakes? Why? Generally speaking, when a car steps on the brake pedal, there will be three different situations, that is, the front wheel slips first, the rear wheel slips first, and the front and rear wheels slip first. At the same time, in these three cases, braking is only different in braking force distribution, not braking first.

Is the ability of four wheels to brake at the same time. Many friends may think that the distance between the brake pipe and the front wheel is short and the distance between the brake pipe and the rear wheel is long, so they mistakenly think that the brakes of the front wheel and the rear wheel should appear in turn when braking. Actually, this view is wrong!

Taking passenger cars as an example, almost all of them use hydraulic braking, so no matter the layout and length of the brake pipeline, the brake pipeline is filled with brake oil (if there are bubbles). Therefore, no matter how big the brake pipe is, the difference between the length of the front and rear brake pipes is that as long as the brake pedal is pressed, the pressure will be generated at the same time.

Therefore, the front and rear brakes work at the same time, but there is a difference in power distribution. The family car is mainly a hydraulic braking system. Step on the brake pedal and control the brake master cylinder. The brake on the wheel is the brake cylinder, which absorbs the brake fluid and transmits the braking force through the brake fluid.

Therefore, air will not be released into the brake pipe because air can be compressed. When braking, the air is compressed by the pressure of brake fluid, and the braking force cannot be transmitted to the wheel brakes. Therefore, after replacing the brake fluid, be sure to pay attention to deflation and protect the brake pipe. If the brake pipe breaks, the corresponding circuit will lose its braking force.

Fortunately, nowadays, cars all adopt dual-loop braking system, that is to say, the master cylinder has two pipes to control the two wheels at diagonal positions, such as one way to control the left front wheel and the right rear wheel, and the other way to control the left front wheel and the right rear wheel. If one of the pipes is broken, both wheels have braking force.

When the ignition switch is turned on, the ABS control unit starts to work. If the driver presses the brake pedal while the car is running, the pedal force will be amplified by the vacuum booster and act on the brake master cylinder. The force on each wheel is equal in theory, but the actual force acting on each wheel is different. If the braking forces are equal,

It will lead to insufficient braking force of the front wheel and excessive braking force of the rear wheel, because under normal circumstances, the car is driven by the front wheel. Theoretically, the distribution of braking force is 60% for the front wheel and 40% for the rear wheel, which can ensure the braking stability of the vehicle. For the actual braking force, the friction between the road surface and the wheels must also be considered, for example, with the increase of braking force.

The braking force of the four wheels increases synchronously, and still moves forward under the action of inertia, and the center of gravity also moves forward. In this case, the load of the front wheel is greater than that of the rear wheel, so the brake pads of the front wheel wear more than that of the rear wheel. Is it feasible to brake only the front wheels or the rear wheels?

Of course not, because no matter what the performance of the car is, the biggest requirement for stiffness is stability. Braking only the front wheel or the rear wheel will inevitably lead to excessive deviation of braking force, which will lead to wheel slippage and cause great damage to the chassis.