Like how does the brake just stay on what brake parks the car what makes it different from the reguler brake
In: Engineering
You use the parking brakes which is a constant break that doesn’t let your car move.
You can also leave your car in first gear just to be extra safe, because of the transmission your car will be harder to move.
Edit: as noticed by u/nrsys this response is only true for cars with manual transmission
The brakes do not park the car. There is a thing in the transmission called a park pawl. When it’s engaged it causes one of the wheels to spin in the opposite direction than the other. With 2 of the wheels not being able to spin in the same direction, the car can’t move.
The transmission has a bar in it that grabs a gear when you put the car in park. This holds it in place so you don’t need any brakes, but it will break if you try and shift into it while moving. [Image of parking pawl.](https://streetsmarttransmission.com/wp-content/uploads/2019/09/e9686848-pawl-in-notin-park_0go07a0gn079000000001-1.png)
A lot will depend on your exact car – different cars will have slightly different systems depending on their transmission types, age and technologies.
Brakes themselves are a pretty simple concept – there is a flat rotor or a steel drum, and when you engage the brake it forces a brake pad against the rotor or drum, and the friction between the two causes the car to stop moving.
Most traditional cars will actually have two braking systems fitted – there is a foot operated hydraulic brake, and separately a cable operated handbrake/parking brake operating a different brake caliper or drum. This allows the hydraulic brake to be a power assisted system that needs the engine to work properly, while the handbrake uses a weaker cable operated system that is not effective enough to slow a car travelling at speed well, but is more than strong enough to hold the car stationary.
Automatic cars will also use a ‘p’ setting on their transmission to prevent the car moving – when you set the shifter to this it will engage a lock that stops the transmission from spinning, which also locks the wheels in place and stops the car from moving.
Some modern cars will also use electronic parking brakes – similar to the other brake systems, but the pads are moved with an electric motor or similar so they can be controlled by a button rather than a lever.
When you park a car, you’re generally supposed to use a brake that is called the handbrake in the UK. In the US, I believe it’s called the e-brake (short for emergency brake), or the…wait for it… parking brake. Apparently in the US, loads of folk don’t use this. Instead, they rely on the gears jamming the wheels, basically. (I’m guessing the reason for the difference is related to the fact that US cars are usually automatic, so have a mode for parking, called park. In the UK, most folk drive manual cars, so this doesn’t exist. You can basically imitate it by parking in gear. But you’re still supposed to use the brake in the US too.) But how does the hand brake work and why is it different from the foot brake?
Simple answer, a ratchet. The foot brake is essentially some pads that move when you press the brake pedal. The pedal pulls a wire which makes the brake pads pinch together and grab the wheel. It’s a bit like the grabber tools that people use for picking litter or if they can’t bend down.
The hand brake is different. It has a ratchet mechanism. That’s a bit like one part that slides across a sort of gear where all the teeth point in one direction. It’s easy for the part to slide across the teeth one way, but it gets stuck when it tries to slip back. When you hear people part in TV or film and there’s that crunch sound, that’s the brake lever slipping across the teeth in the ratchet. This keeps the brake in place. When you want the car to move again, there’s a button on the brake lever that you press. This releases the lever from the ratchet and allows the brake to be released. Arguably, you’re actually supposed to use the button when applying the brake too, so you don’t scrape the teeth down to the point where they don’t work. So you shouldn’t really hear that sound in films! But it’s a bit hit or miss whether people do this or not.
In a car with an automatic transmission, when you shift into `P`, there’s a little peg called the “parking pawl” that sticks into one of the gears of the transmission, physically locking it.
In both automatic and manual cars, there’s also the “parking brake”. The parking brake is a special brake separate from the normal brakes, and is usually engaged purely mechanically – the parking brake lever physically pulls a cable or hydraulic cylinder to clamp the parking brake down.
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