Photo: spare brakes in a car (Getty Images) Author: Konstantin Shirokun
It is not customary to duplicate systems and units in a car. But one system does have, so to speak, a double version. We tell you about spare brakes and how to use them if necessary.
Read about the types of spare brakes available in a car in the RBC-Ukraine article.
It is not surprising that brakes have become the only system that has a “double” on modern cars – after all, among all the systems necessary for safety, brakes are the most important.
Where to look for spare brakes
Actually, you don't have to look for them – the spare brake is always literally at hand: it's the handbrake, the same parking brake. Modern cars have become so reliable that most owners don't even know about the second function of the handbrake.
From a technical point of view, loading the handbrake with an additional emergency braking function was a good idea. After all, the parking brake, being a brake, is largely independent of the main – so-called service – braking system. However, it should be recognized that some modern cars have questions about the reliability of the backup braking system.
How many brakes does a car have?
Any passenger car has two braking systems – the main, working one, plus a parking one, also a reserve one. Just twenty years ago, these two systems were separate and the failure of one did not prevent the second one from at least somehow stopping the car. Which, in fact, is what fundamentally ensured the reliability of the reserve brake.
It is probably appropriate to recall that the main system in a passenger car is hydraulic, the force from the pedal to the pads of each wheel is transmitted by liquid that moves through tubes. And the classic type handbrake has a separate mechanical drive – a cable and levers that connect the handbrake lever to the pads that are pressed against the disks or drums (sometimes, by the way, also separate).
However, at the beginning of the century, an electric handbrake appeared.
Electric handbrake – spare brake
At least half of modern cars have a completely different design of the parking brake – electric, and even with electronic control. The lever or separate pedal was replaced by a button, the cables under the bottom were replaced by wires, steel rods near the pads of each wheel gave way to electric motors with a gearbox.
This system fundamentally changed the algorithm for using the parking brake: the driver does not even have to press the button, the electric drive is easily automated. In addition, designers willingly used such a brake for electronic assistants such as Auto Hold, Stop & Go, Hill Assist. All this is good, but as a spare brake such a handbrake is not as good as a purely mechanical one.
How to brake with an electric handbrake while driving
The worst thing is that the designers did not trust the electronic handbrake to brake from high speed. A typical electronic handbrake in emergency brake mode works like this.
If the main brake system suddenly fails while driving, the driver must press the handbrake button or key. However, the electronics first activate the hydraulic drive of the main brake system – the same one that just failed! And only after the car slows down to 7 – 10 km / h, the electronics will turn on the parking brake with an electric drive subordinate to it – and it should completely stop the car. However, how the problematic main system will brake the car to those 7 – 10 km / h is not exactly known.
Therefore, in case of problems with the working system, the owner of a car with an electric parking brake has all the hope of relying on the high reliability of the current technology. But it, of course, has an age limit, and on an old car, the brakes will sooner or later fail – just like other systems. Therefore, regardless of the age of the car, the brakes must be maintained in proper condition.
In brief
The older your car is, the more often you need to show its brake system to mechanics at a service station you trust. In principle, it is not so difficult to restore the brakes of an old car to the level of reliability of a young model, because the list of components that can become a weak link is well known to both servicemen and spare parts suppliers.
In preparing this article, materials from Autobild and Autocentre were used .
Let us recall that RBC-Ukraine recently reported why pedestrians are not always right.