Every mechanical device capable of motion is it a car or cart does have a brake as a component, thus incorporating it into our lives every day. A much-clarified description of the vehicular component brake would be:
- A brake is what makes the device or automobile motionless for the time being
The brakes in your car are a vital part without which your life is in constant danger. It is extremely essential to keep your brakes in the most competent position at all times, hence making it the most important component of your vehicle.
It sucks when you are having trouble with the brakes on your car, and the mechanic utters complicated terms such as ‘disk brakes’, ‘drum brakes’, ‘hydraulic fluids’, ‘piston’, etc. You’d feel vulnerable and worry that you might get scammed. Well, we’re here to impart some knowledge about this important set of mechanical components engineered into our daily lives via automobiles.
To begin with, braking systems have evolved through the years. About over a century ago, brakes were still on an improvising basis which indicates that although various vehicles were common back in the day, stopping them was not as easy as it is now. From tire brakes on a four wheeler horse coach to the anti-brake locking system, brakes have come a long way.
The framework for the brakes we use today was established in around 1945 with the Studebaker 1946 model. In current times, the fastest and the most efficient brakes are found in the cars that race for Formula 1 World Championship.
Basics about Brakes
There are different sorts of brakes within your car and also among two automobiles. Let’s warm you up with basic knowledge about the set of brakes you can find in your car. There are more than one brakes in your car, and they are used in more than one scenarios. One is when the driver is maneuvering the vehicle and wants to slow down or stop at a signal i.e. Ordinary driving scenarios.
The emergency brakes are for urgent situations where the vehicle might be on the verge of collision i.e. an exceptional driving scenario. There is also a different mechanism of brakes used for when you’re parking.
How Does a Brake Work?
The most common kinds of braking systems you need to remember are Service brakes, Emergency Brakes, and Antilock Brakes System. These systems are found in a typical braking system.
We shall ease your way into it. Let’s start with pedals and then accelerate our way inside the mechanism. When you push the brake in your car, you’re actually creating the momentum that is carried through the pedal towards the master cylinder which is then immediately forwarded to the wheels. The ‘momentum’ is, in fact, Hydraulic oil aka Brake fluid, and it carries the force to each wheel like a steel rod being pushed through a tube.
Why Hydraulic oil?
With the medium substance being in the liquid state, it enables easy flow through tubes, pipes and hoses which are present in the braking system of your car. Without air bubbles in the oil, the brake fluid is capable of flowing rapidly through the master cylinder to the wheel with the exact same pressure you pushed the brake.
Air makes the consistency spongy; thus, defeating the efficiency of the entire braking system. To ensure that there is no air in the fluid, we have ‘bleeding screws’ at intervals in cylinders of the wheels as well as calipers. The number of components and the way those components work in separate braking systems differ.
For example, in disk brakes and drum brakes, it works like brakes on a bicycle except with pads and shoes respectively. The mechanism of brakes is based on the same prototype of creating friction to slow down the motion of the vehicle, but it differs at some level.
Service brakes are the braking system we make the most use of. While slowing down the vehicle, stopping at a signal or just to keep the vehicle at a stationary position, Service Brakes are used. These brakes are used for the most ordinary scenarios while driving a vehicle. The left pedal you find below your steering wheel is primarily used to operate the Service Braking System.
There is further diverse application of the Service Braking System. The one in your vehicle works on any of the following three mechanical principles:
- 1. Electromagnetic Braking: This type of braking system is majorly found in locomotive automobiles like trams and trains. Earlier on it was called Electro-Mechanical brakes, which gradually changed to Electromagnetic because of its literal meaning defining the type of brake. Over the years, its application and variation in different aspects have developed drastically. Originally, electromagnetism depends on kinetic energy born due to heat but eddy current brakes depend entirely on Electromagnetism.
- 2. Frictional Braking: This is a very well-known principle applied in most braking systems today. You can see the framework of a braking system working on friction in bicycles. But in larger vehicles like cars or trucks, the braking system is complex. Although it works on the basic principle of friction, but with a number of components to get the desired result. Brake pads or shoes are rubbed against the rotor with the help of calipers in a rotating motion inside the braking system to create heat by the mode of friction in the forward moving vehicle, thus slowing it down or bringing it to a complete halt. The use of either Brake pads or shoes depends on the braking system- Disk or drum, respectively.
- 3. Pump Braking: To pump your brakes is popularly called Cadence braking or Stutter Braking. It cuts off the fuel supply within the vehicle via a piston motor. When the fuel supply to the engine is cut, the vehicle gradually comes to a halt. It is mostly used to maneuver the vehicle or brake on a slippery surface to avoid skidding. This braking system is overshadowed by the concept of Anti-Lock Braking Systems in modern cars, but it’s a skill worth learning.
The Service Braking System is made up of different frameworks depending upon the type of vehicle it is engineered for. The complex grouping and placement of components differ with the vehicle type. It could be either of the following or a combination of two:
Disc brakes were earlier on called plates or plate brakes. These are an ideal sort of brakes today with less wear, more efficiency, self-cleaning, self-adjusting and can be used to stop even jumbo jets. Disc brakes by default are used to control the front wheels of an automobile. In some cases, disc brakes are used even in the rear wheels, but not necessarily.
Why do we have disc brakes on the front wheel by default?
When a car has to be stopped, the front wheels play a more imminent role than the rare wheels. Disc brakes are proved better in braking than other braking systems in the market today; it is the choice of every engineer. To decrease the chances of inefficiency to failure, we always employ Disc Brakes to the front wheels.
Brakes are applied in the forward moving vehicle by the heat caused due to friction in the wheel brake. A wheel brake is applied to slow down the vehicle’s wheel rotation thus bringing it to a gradual halt. Two pads are set in place inside the wheel brake, and when the brake is applied, the metal pads in the brakes are pushed against a rotating component via the calipers set in place.
So if Disc Brakes are the proven best brakes, how come we still have Drum Brakes?
Drum Brakes are less expensive as compared to Disc Brakes. It is cheaper to engineer a drum brake into the rear wheels not only because of how much it costs but also because installing Parking Brakes on the rear wheels becomes easier. With a disc brake in the rear wheels, we have to install a whole new system for Parking Brakes. But if a drum brake is installed in the rear wheels, parking brakes can be activated only by adding a lever.
The components used in a Drum Brake are:
- Brake drum
- Brake shoes
- Backing plate
- Wheel cylinder
- Return springs
- Automatic adjusting framework
When the brake pedal is pushed, the hydraulic oil (pressure) pushed the wheel cylinders to rub brake shoes against the brake drum thus causing friction. When the brake is successfully applied, the shoes return to their previous position with the help of Return Springs.
With constant and regular use, the wear of these components especially brakes shoes must be checked. When the metal of the shoes becomes visibly worn, it is highly recommended to get it changed for your own safety. Any brake failure caused due to the inefficiency of this system can result in dangerous repercussions.
- The mechanical principle of applying the brake in a Disc brake framework and a Drum brake frameworks is almost the same.
- Brakes are applied in the forward moving vehicle by the heat caused due to friction caused by shoes/pads of the brakes and the surface.
- A brake through the pedal is applied to slow down the vehicle’s wheel rotation thus bringing it to a gradual halt.
- The brake shoes/pad are made of steel/metal, and they are pushed against the surface via the brake fluid.
- The difference lays in the use of different components to cause friction and the addition of Return springs in the latter.
Antilock Braking System (ABS)
It is a braking system evolved in the modern era. Found in newer models, Antilock Braking system goes literally by its name. It is utilized under heavy braking. It helps the wheels when the brakes are pushed too hard (especially in the case of emergencies), and when the wheels are on the verge of getting locked thus causing a possible skid.
If heavily braked, the rear wheels might face a lot of weight, and that can result in locking of wheels consequently, a skid. When rear wheels are engineered into an automobile, they are made less powerful on purpose. With the ABS, any chances of wheels getting locked are eliminated.
The Antilock Braking skid works with from within the brake system using three components: the central Electronic Control Unit, Speed Sensors on the wheel and valves in the hydraulic pumps. What the ABS does it that if it detects that a wheel is going visibly slower or faster than other wheels, it reduces or increases the hydraulic pressure towards the wheel, thus avoiding misbalancing and possible accidents on the road.
Single-Circuit Hydraulic Brakes
The hydraulic brake fluid flows to the master cylinder when the driver applies a brake. The system has connected the master cylinder with a series of metal pipes, tubes and hoses installed at the wheel cylinders. Each wheel brake has opposite pistons on drum or band brake. When the pressure is applied on the brake pedal, pistons located at the wheel cylinder are pushed apart and it in turn forces brakes pads into wheel cylinder.
Dual-Circuit Hydraulic Brakes
It is a primary command circuit for when the pressure on the brake is applied and a secondary circuit controlled by a computerized system in the car that incorporates the force applied and inserted the same into the hydraulic pump system.
It is a system with integrated cable wires which when pressure on the brake pedal is applied, calculates electrical resistance and directs signals to the computer system in the car, which measures applied force and directs the same to the hydraulic pump system.
Power Brake Booster
This braking system can be utilized to stop even the heaviest of automobiles using the naturally born vacuum force within the engine combined with the outside air to exaggerate the pressure applied by the driver on the brake pedal. The master cylinder is connected to the brake pedal with air valves, which open in the diaphragm’s rear to let in outside air.
With the pressure of the air received from outside depending on the speed of the automobile, the piston on the master cylinder is pushed; thus, assisting the brakes to stop the vehicle. The same mechanism can be followed even when the engine is off because of the direct link of the master cylinder with the brake pedal created via a servo fitted in the framework, but with much more exerted power on the brake pedal.
It works the same way as a typical braking system. Just that instead of the brake fluid or the Hydraulic oil, Air is used as a medium. Air is pushed through the tubes to apply force to a drum brake or disk brake. Air brakes are normally applied in braking systems of large vehicles like trucks, trailers, and buses.
Advanced Emergency Braking System (AEBS)
This is an advanced braking system, not found in regular cars in today’s time. By the help of sensors installed in the car, the system monitors how close other vehicles are to the car. If the proximity is too close, the brakes are automatically applied on the car thus avoiding any chances of collision or accidents. Although this braking system sounds like a hoot in terms of automated safety, it is ridiculously expensive which makes it all the rarer to use.
Brakes are usually applied to a rotating surface within the wheel brake, but in certain cases, it is deployed on to substantial surfaces such as air or water.
How does that work?
- Well, in airplanes, they have a combination of wheel brakes and air brakes for when they wish to slow down in the air.
- So the pilot opens up flaps on the sides of the aircraft, thus going against natural airflow. That helps in reducing speed in air.
- Same goes with watercrafts.
- Flaps are opened up in water, going against the natural flow of water causing a slower speed or total halt.
- These Service Brakes whether run on hydraulic pressure, computerized systems, air or water, they are mechanized to keep your safety in check.
- The type of Service Braking System chosen for the vehicle depends on upon the type and weight of the automobile.
- The best technology is used in evolving automobiles only to enhance your driving experience.
- But the brakes you use while driving your car are different from the brakes you use in emergency situations.
The mechanism used for parking your car is somewhat similar to the other Braking Systems. But the tool used to apply a brake while parking is different. You usually find a tiny pedal beneath the steering wheel in the driver’s area, or a handbrake is used after halting the vehicle to keep the car stationary on a flat of the inclined road.
A handbrake is a lever you find between the two front seats that runs on the mechanical force. It is linked to wheel brakes overlapping the service brake systems to function smoothly in case of a brake failure.
Some advanced models have replaced the levers/latches with just a tiny button. It latches the wheel directly on the signals of the parking brakes located in the driver’s cab.
The use of parking brakes and emergency brakes differs only as per the situations. Parking brakes are used when the car is in a very slow motion with an intention to halt/park whereas emergency brakes are used when the car is in regular motion, i.e. when the car is being driven to avoid a collision or accident. Therefore, the same tools are used for Parking as well as Emergency situations.
But how does the car system evaluate the purpose for which the tool was hit?
- The car system has an equalizer in the braking system. Only the rear wheels of the automobiles work for emergency brakes.
- Depending on the pressure applied on the brakes combined with whether the car was stationary or in motion determines with what intention the brakes were used.
- The equalizer divides the signals towards both rear wheels directing it to slow down.
- If the car was in speed, it might cause the rear wheels to skid due to the misbalancing within the wheels and braking system; thus, causing a probable accident.
- If you have a well-mechanized combination of service brakes and emergency brake with a good maneuvering of the vehicle, you might not face a possible skid.
- It was created to reduce skidding in the rear wheels caused due to emergency brakes or heavy service braking.
- The ABS is an excellent safety system found mostly in newer and advanced models of automobiles.
- Wear and Tear: Get your service brakes check every now and then. The pads, shoes, and brake linings may have worn off due to constant braking. Check for noises like grinding and squeaking. Also, if the car takes the time to halt, you know where to start checking.
- Have the pipes and tubes in the braking system check. Check for air bubbles in the hydraulic oil, causing it to be spongy; thus, make it in inefficient. The valves connecting the master cylinder, pedals and the wheel brakes (fluid and air) need to be checked as well.
- Don’t accelerate and brake together. You might not see visible consequences, but long time braking causes the brakes to heat up. Slow your car down to medium speed, and then hit the brakes to come to a halt.
You have now gained complete knowledge about the mechanism of the braking systems in your automobile, the variations and applications of usage in different conditions and different vehicles. It also equally important to maintain and upgrade the braking system and its components are important to ensure the safety of you and your loved ones. The failure of your braking system can cost you life. Discuss the brake system of your car and maintain it with the help of your mechanic.
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