Тормозная система автомобиля: назначение, устройство и принцип работы

Автомобильные тормозные системы, виды, устройство, как работают

Тормозная система необходима для быстрого изменения скорости или полной остановки автомобиля и удержания его на месте при стоянке.

Для этого на автомобиле есть такие виды тормозных систем, как — рабочая, стояночная, запасная и вспомогательная система (тормоз-замедлитель).

Рабочая тормозная система всегда используется при любой скорости автомобиля для полной остановки или для снижения скорости. Рабочая тормозная система начинает работать при нажатии на педаль тормоза. Эта система самая эффективная при сравнении с другими видами.

Запасная тормозная система применяется при неисправности основной системы. Запасная тормозная система бывает в виде автономной системы или её функции выполняет часть исправной рабочей тормозной системы.

Стояночная тормозная система необходима для удержания автомобиля определенное время на одном месте. Стояночная система полностью исключает движение автомобиля самопроизвольно.

Вспомогательная тормозная система применяется на автомобилях с повышенной массой. Вспомогательная система используется для торможения на спусках. Часто бывает, что на автомобилях роль вспомогательной системы выполняет двигатель, где выпускной трубопровод перекрывается заслонкой.

Тормозная система — это важное средство автомобиля для обеспечения активной безопасности. На автомобилях применяются разные системы и устройства, повышающие эффективность системы при торможении — это антиблокировочная система, усилитель экстренного торможения, усилитель тормозов.

Тормозная система включает в себя тормозной привод и тормозной механизм.

Схема гидропривода тормозов:
1 — трубопровод контура «левый передний-правый задний тормоз»; 2-сигнальное устройство; 3 — трубопровод контура «правый передний — левый задний тормоз»; 4 — бачок главного цилиндра; 5 — главный цилиндр гидропривода тормозов; 6 — вакуумный усилитель; 7 — педаль тормоза; 8 — регулятор давления задних тормозов; 9 — трос стояночного тормоза; 10 — тормозной механизм заднего колеса; 11 — регулировочный наконечник стояночного тормоза; 12 — рычаг привода стояночного тормоза; 13 — тормозной механизм переднего колеса.

Тормозной механизм блокирует вращение колес и как результат появление тормозной силы, которая останавливает транспортное средство. Тормозные механизмы находятся на задних и передних колесах.

По идее — все тормозные механизмы логично называть колодочными. И уже в свою очередь, их можно разделить по трению — дисковые и барабанные. Тормозные механизмы основной системы монтируются в колесе, а механизм стояночной системы находится за раздаточной коробкой или коробкой передач.

О барабанных и дисковых тормозных механизмах

Тормозной механизм обычно состоит из двух частей, из вращающейся и неподвижной. Вращающаяся часть барабанного механизма — это тормозной барабан, а неподвижная часть – тормозные колодки.

Барабанные тормозные механизмы обычно стоят на задних колесах. В процессе износа зазор между барабаном и колодкой увеличивается и для его устранения есть механические регуляторы.

Барабанный тормозной механизм заднего колеса:
1 – чашка; 2 – прижимная пружина; 3 – приводной рычаг; 4 – тормозная колодка; 5 – верхняя стяжная пружина; 6 – распорная планка; 7 – регулировочный клин; 8 – колесный тормозной цилиндр; 9 – тормозной щит; 10 – болт; 11 – стержень; 12 – эксцентрик; 13 – нажимная пружина; 14 – нижняя стяжная пружина; 15 – прижимная пружина распорной планки.

На автомобилях тормозные механизмы могут иметь разные сочетания:

• два дисковых передних, два барабанных задних;
• четыре дисковых;
• четыре барабанных.

В тормозном дисковом механизме — диск вращается, а две колодки стоят неподвижно, они установлены внутри суппорта. В суппорте стоят рабочие цилиндры, они при торможении прижимают к диску тормозные колодки, а сам суппорт хорошо закреплен на кронштейне. Для улучшения отвода тепла из рабочей зоны часто применяют вентилируемые диски.

Схема дискового тормозного механизма:
1 — колесная шпилька; 2 — направляющий палец; 3 — смотровое отверстие; 4 — суппорт; 5 — клапан; 6 — рабочий цилиндр; 7 — тормозной шланг; 8 — тормозная колодка; 9 — вентиляционное отверстие; 10 — тормозной диск; 11 — ступица колеса; 12 — грязезащитный колпачок.

О тормозных приводах

В автомобильных тормозных системах нашли применение вот эти типы тормозных приводов:

• гидравлический;
• пневматический;
• комбинированный.
• механический;

Гидравлический привод получил самое широкое распространение в рабочей тормозной системе автомобиля. В него входят:

• главный тормозной цилиндр;
• тормозная педаль;
• колесные цилиндры;
• усилитель тормозов
• шланги и трубопроводы (рабочие контура).

При усилии на тормозную педаль водителем, та передает усилие от ноги на главный тормозной цилиндр. Усилитель тормозов дополнительно создает усилие, облегчая тем самым жизнь водителя. Широкое применение на машинах приобрел вакуумный усилитель тормозов.

Главный тормозной цилиндр нагнетает тормозную жидкость к тормозным цилиндрам. Обычно над главным цилиндром стоит расширительный бачок, в нем содержится тормозная жидкость.

Колесный цилиндр прижимает тормозные колодки к тормозному барабану или диску.

Рабочий контур сейчас представляет из себя основной и вспомогательный. Например, вся система исправна, то значит работают оба, но при неисправности одного из них — другой будет работать.

Широко распространены три основные компоновки разделения рабочих контуров:

• 2 + 2 подключенных параллельно — задние + передние;
• 2 + 2 подключенных диагонально — правый передний + левый задний и так далее;
• 4 + 2 в один контур подключены два передних, а в другой тормозные механизмы всех колес.

Схема компоновки гидропривода:
1 — главный тормозной цилиндр с вакуумным усилителем; 2 — регулятор давления жидкости в задних тормозных механизмах; 3-4 — рабочие контуры.

Прогресс не стоит на месте и сейчас в состав гидравлического тормозного привода добавляются разные электронные компоненты:

• усилитель экстренного торможения
• антиблокировочная система тормозов;
• антипробуксовочная система;
• система распределения тормозных усилий;
• электронная блокировка дифференциала.

Пневматический привод применяется в тормозной системе большегрузных автомобилей.

Комбинированный тормозной привод — это комбинация разных типов привода.

Механический привод применяется в стояночной тормозной системе. Он включает в себя систему тяг и тросов, с помощью которых объединяет систему в одно целое, обычно на задние колеса имеет привод. Рычаг тормоза соединен при помощи тонкого троса с тормозными механизмами, где есть устройство, которое приводит в действие основные или стояночные колодки.

Есть автомобили, где стояночная система работает от ножной педали. Сейчас всё чаще стали применять в стояночной системе электропривод, который получил название — электромеханический стояночный тормоз.

Итак, как работает гидравлическая тормозная система

Осталось рассмотреть работу тормозной системы, что мы сделаем на примере гидравлической системы.

Когда водитель нажимает на педаль тормоза, то передается нагрузка к усилителю и тот создает усилие на главном тормозном цилиндре. А в свою очередь поршень главного тормозного цилиндра через трубопроводы нагнетает жидкость к колесным цилиндрам. Поршни колесных цилиндров от давления жидкости передвигают тормозные колодки к дискам или барабанам и происходит торможение автомобиля.

Когда водитель убирает ногу с педали тормоза, то педаль от действия возвратной пружины возвращается в начальное положение. Также, в свое положение возвращается и поршень главного тормозного цилиндра, а пружины отводят колодки от барабанов или дисков. Тормозная жидкость возвращается обратно в главный тормозной цилиндр и падает давление в системе.

Видео: принцип работы тормозной системы.

Вот на этом пожалуй и завершу свою не маленькую статью. Всем удачи на дорогах!

Загрузка… 90000 The Ultimate Guide to Car Brakes 90001 90002 90003 Home 90004 90003 Сategories 90006 90003 Accessories 90006 90003 Interior Accessories 90004 90003 Exterior Accessories 90004 90003 Toys 90004 90015 90004 90003 Cleaning & Detailing 90004 90003 Electronics 90006 90003 Audio 90004 90015 90004 90003 Engine & Performance 90004 90003 Tools 90004 90003 Tires & Wheels 90004 90003 Motorcycles & Bikes 90004 90003 Home Care 90004 90003 RV Campers 90004 90003 Off-Road Vehicles 90004 90003 Warranties 90006 90003 Extended Warranties 90004 90003 Factory Warranties 90004 90015 90004 90015 90004 90003 Blog 90004 90003 Tools 90006 90003 Tire Size Calculator 90004 90003 Wheel & Tire Finder 90004 90015 90004 90003 About Us 90004 90003 Contact 90004 90015 90002 90003 90066 90004 90003 90066 90004 90003 90066 90004 90003 90066 90004 90015 90002 90003 Home 90004 90003 Сategories 90006 90003 90004 90015 90004 90015.90000 9 Parts of a Brake System (and Their Functions) 90001 90002 The car brake system has one critical job. Its main purpose is to allow the driver to slow down or stop the vehicle. 90003 90002 Each time you step on the brake pedal, the speed of the spinning wheels underneath your vehicle is reduced proportionately to how much pressure you apply to the pedal. A vehicle will have either a disc braking system or drum braking system to create the necessary friction for this to take place. 90003 90002 Modern car brake systems are referred to as power brake systems.These systems use hydraulic technology and fluids to make braking so much easier for drivers. Power braking allows you to apply just a little bit of pressure to the brake pedal in order for the vehicle to slow down. 90003 90002 This is much better than the traditional brake systems where you had to step hard on the brake pedal just to slow it down to a stop. In emergency situations, you’ll be glad to have power brakes with hydraulics. 90003 90002 In the classic mechanical brake system, there was a cable which connected the brake pedal and brake shoe assembly together.When the driver stepped on the brake pedal, it pulled on the cable and allowed the brake drum spinning to slow down. 90003 90002 When the disc braking system was invented, the disc was used instead of the drum. Then as computer technology got more advanced, the power brake system took over and eliminated the need for the cable. 90003 90014 Car Brake System Components 90015 90002 Below is a list of the components of a car brake system. We have included both the components of the disc and drum brake systems.Remember that cars only have one or the other, but not both together. 90003 90018 1) Master Cylinder 90019 90002 There are really 2 individual cylinders in a single unit. Each cylinder manages the braking ability of the 2 front wheels. That way, if one cylinder fails, the other cylinder can still slow down the wheels. 90003 90002 The master cylinder works by managing the amount of hydraulic pressure that is placed on the hydraulic fluids. More pressure means a faster ability to slow down the vehicle.90003 90018 2) Brake Rotor (disc brakes) 90019 90002 Each wheel has a brake rotor which spins while the vehicle is moving. The brake pad and caliper rub against the rotar and create the necessary friction to slow down the disc. This, in turn, slows down the wheel and vehicle. 90003 90018 3) Brake Drum (drum brakes) 90019 90002 The brake drum is the alternative to a brake rotor when you have a drum brake system. As the drum component spins, the brake shoe goes inside and pushes against it when you step on the brake pedal.90003 90018 4) Brake Pad (disc brakes) 90019 90002 In a disc brake system, the brake pad and its caliper create friction as they rub against the spinning brake disc. 90003 90018 5) Brake Shoe (drum brakes) 90019 90002 This is the alternative to the brake pad when you have a drum brake system. The brake shoe is what rubs against the interior of the brake drum when you step on the brake. 90003 90018 6) Brake Booster 90019 90002 The brake booster is part of the power braking system. It is what amplifies the foot pressure that you place on the brake pedal in order to make it easier to slow down the vehicle.90003 90018 7) Brake Pedal 90019 90002 The brake pedal should be obvious. This is the pedal next to the gas pedal that you step on to slow down the vehicle. It is connected to the entire braking system on the inside. 90003 90018 8) Anti-Lock Sensors 90019 90002 Power brake systems have anti-lock brake sensors which detect how fast each wheel is spinning. If your wheels lock up because you slam on the brakes out of panic or fear, then anti-lock sensors will keep your brakes pumped so that you can steer the wheel.90003 90018 9) Brake Lines 90019 90002 Brake lines transfer brake fluid between the master cylinder and wheels. This is the hydraulic fluid that allows braking to be so easy. 90003.90000 How does the Brake System Work? (6 Tips for Maintenance) 90001 90002 The brakes are the most important active safety of a car and one of its key pieces. However, many drivers do not seem to understand it well. According to statistics, about 40% of the defects detected by the ITV correspond to the brakes. It is not enough to bring the car to the shop when something goes wrong. Care should be taken earlier for your car security feature before facing an accident. Have the brakes checked? The braking system is the vehicle’s most important safety item.90003 90004 External elements that influence the braking 90005 90004 90007 90005 90002 Keep your car in perfect condition during springs. A damping brake System responsible for an increase of 10% in the distance necessary to restrain. Keep an eye on the state and the pressure of your tires because they determine the effectiveness of the braking since one of its missions is to convey the power and braking. 90003 90002 Take into account the state of the road, there are asphalt, which grips better than others, and the weather also affect the efficiency and capacity of the braking.Exercise caution when snow and ice (the adhesion is practically zero) and the first drops of rain, mixed with dust and dirt of the driveway, turned in a strong slider. 90003 90002 In the long journeys should stop and rest every two hours. 90003 90004 How does the brake system work? 90005 90004 90018 90005 90002 Blaise Pascal was a seventeenth-century French mathematician and philosopher who formulated the principle that a change of pressure at one point of a confined fluid is communicated undiminished to all parts of the fluid.In an automobile braking system, the brake lines are filled with just such a ‘confined fluid’. When pressure is applied via the brake pedal from a piston in the master cylinder, the pressure is transmitted equally to all four brakes. 90003 90002 «Pressure on the brake pedal forces the brake fluid in the master cylinder (the container for brake fluid) through the brake lines to the wheel cylinders to stop the car,» explained Andrew Brown, an auto mechanic with over 25 years ‘experience in the motoring world.»One part of the dual master cylinder connects with the front wheels, the other with the rear wheels,» he adds. 90003 90004 Brake fluid 90005 90004 90027 90005 90002 Brake fluid is hygroscopic which means not only does it absorb water, but it attracts water. Flushing the brake system at a maximum of every 2 years (You’re way off schedule) can save many hundreds or in some cases thousands in brake system repairs over the life of the vehicle. Transmission fluid flushing every 2 years or 24,000 miles can double or triple the life expectancy of modern high-dollar automatic transmissions.90003 90004 Tips for braking system Maintenance 90005 90004 90034 90005 90036 90037 Verify whenever possible the power of braking of each of the four wheels with a brake meter / brake tester. Do not forget to check the effectiveness of the circuit. 90038 90037 Keep the indicated level of brake fluid. Check it often, and replace every two years or 50,000 miles. 90038 90037 Be sure to review each time the status of brake pads. Their average life is 25.000 km but can become blunt before its hardness and lifestyle.90038 90037 You must change the brake shoe (or a shoe or a brake block) for every four changes of brake pads or so. 90038 90037 Check to see their headlights and brake lights are working. Also, he urges people to make sure to aim the headlights properly. 90038 90037 Do not modify the original brake system. Observe the times given by the manufacturer. 90038 90049 90004 Symptoms that braking system goes wrong 90005 90004 90053 90005 90055 90037 If your car may be slowing somewhat because it is little brake fluid, because the pads are worn (in which case you hear a chirping) or because the discs are worn.90038 90037 If you brake hard you might have a problem with the servo brake. 90038 90037 If the car slows down and loses liquid badly it is possible that the brake pump is in poor condition. 90038 90037 If the car tends to stop the «tilted» check the pressure, the wear, and alignment of the tires. If these are kept in proper condition, which can brake discs are badly located or that the brake adjustment is uneven. 90038 90037 Also, it can happen that one has strained greasy between the brake pads and the disc, or a flight of liquid or excessively soft damping.90038 90037 If you notice the brake pedal is soft it is possible that air in the circuit has been introduced or that the brake liquid is little. 90038 90068 90004 How to Prevent 90005 90071 With conventional brakes 90072 90002 Do not make «hard braking.» In order to restrain of suitable form exert the same pressure on the pedal without getting to the bottom to prevent the wheels are blocked. If this happens, lift a little pressure on the brake pedal to feel that the wheels spin, and then gently press.90003 90071 With ABS 90072 90071 90078 90072 90055 90037 The ABS (Anti-Lock Braking System) is a braking system that allows that when stops the wheels, not they block, and therefore they continue turning, which allows that they obey to the turn that is marked to him from the steering wheel. 90038 90037 The right way to stop a car equipped with ABS brakes is to hit the brakes and did not release pressure until the vehicle is stopped. During braking and subject to activate the ABS, will be felt a vibration in the pedal.This effect is normal, Is the way the car to tell us that the ABS is working. 90038 90037 It only acts when stepping on the brake with force. 90038 90037 To obtain an effective braking system must step on the brake pedal with the force from the outset while stepping on the clutch. In performing this maneuver will cause the car to responds to its maneuverability and achieved its arrest in a shorter space. 90038 90068 90004 How do I know that the ABS on my car is running? 90005 90004 90093 90005 90002 Just start the car, turn on a light og ABS signal.The light should turn off after a few seconds. If the ABS does not shut down, it means that the ABS does not work. Still, you can stop the car, but do not have the help of ABS. It would be advisable to bring a workshop to review. 90003 90071 With the change: 90072 90055 90037 Use the gearbox to slow it is a maneuver can be very useful in prolonged reductions, as they can be the mountain ports. 90038 90037 Never slow down with clutch into neutral to save fuel. 90038 90037 Before cutting a shorter running the vehicle must have diminished his speed, since otherwise when it loosens the clutch engine can be passed speed.90038 90037 The revision of the brakes must be released once a year of the obligatory way like minimum 90038 90068 90071 Systems that help to restrain 90072 90055 90037 In the maneuvers critics, like the braking in curves or with the wet road or frost, electronic systems of traction control have been designed (ASR / TMC) that detect the moment at which a wheel is going to accelerate itself with respect to the others and reduce the transmitted force the slowing it or combines both actions. 90038 90037 The dynamic control system (ESP / FDR) prevents slippage of the vehicle in the transverse direction, which keeps track on the curve, and avoids avoid drifting.90038 90037 Control of braking in curves (CBC), related to the ABS, offsets any destabilizing the normal movement of the axle under braking into a curve, with a sensitive regulation of the braking pressure at each of the wheels. 90038 90068 90004 Other systems 90005 90055 90037 BAS (Brake Assistance System), DBC (Dynamic Brake Control), NBA (Nissan Brake Assistance). With these acronyms are identified systems to assist braking developed by various automotive companies. In essence, they are based on strengthening the pressure on the pedal brake when it detects a pisotón.Increase the effectiveness of the ABS, shortening the distance braking. 90038 90037 Electronic distribution of the braking force. It is an active safety system that distributes braking force between each axle depending on the vehicle load or the state of the road. 90038 90037 EBV (Electronic Brake-force Variable). Sharing system variable braking. Its operation is equivalent to the EBD 90038 90037 HDL (Hill Descent Control). Interacts with the ABS to avoid loss of traction in steep declines in vehicles.90038 90068 90002 90132 90003.90000 Brake Systems in Cars | CarTradeBlog 90001 90002 Over the last few weeks, we have covered various parts of the car, including transmission, suspensions and engine fluids. While transmission is connected to accelerating and moving the car, and suspensions are related to a smooth drive, another key system is the braking system, which as we all know serves to stop the car. Today we check out the car’s braking system. Do share your comments and feedback. 90003 90002 Brakes are one the key parts of any vehicle, without which it is virtually not possible to use the vehicle for travel.Clearly, a brake, which serves to slow down the vehicle, should not be too weak. But interestingly, when designing a brake system, it should also be taken care that it’s not too efficient. A too strong a brake would expose us continuously to the ill effects of a sudden brake application in bus or car. If a vehicle is stopped abruptly or strongly, the passenger may hit the front seat or whatever is there. Hence, too efficient a brake system is not required! 90003 90002 The braking system is strongly relation to Newton’s laws of motion.Indeed, the above phenomenon is linked to Newton’s second law of motion, which states «A body continues to be in its state of rest or of motion unless external force acts on the same». 90003 90002 On the other hand, if a brake system is too weak, the stopping distance would increase and hence may lead to accidents. Thus, a brake system should be perfect enough to stop the vehicle at minimum safe distance, without affecting the comfort of the passenger. In an endeavour to achieve this there have been a lot of developments in the brake system technology, right from Mechanical brakes to Air brakes in automobiles.In this article we would like provide the relevant information regarding the same 90003 90002 90011 Braking — fundamentals: friction and how it applies to automobiles 90012 90003 90002 A brake system is designed to slow and halt the motion of vehicle. To do this, various components within the brake system must convert vehicle’s moving energy into heat. This is done by using friction. 90003 90002 Friction is the resistance to movement exerted by two objects on each other. Two forms of friction play a part in controlling a vehicle: Kinetic or moving, and static or stationary.The amount of friction or resistance to movement depends upon the type of material in contact, the smoothness of their rubbing surfaces and the pressure holding them together. 90017 Thus, in a nutshell a car brake works by applying a static surface to a moving surface of a vehicle, thus causing friction and converting kinetic energy into heat energy. The high-level mechanics are as follows. 90003 90002 As the brakes on a moving automobile are put into motion, rough-textures brake pads or brake shoes are pressed against the rotating parts of vehicle, be it disc or drum.The kinetic energy or momentum of the vehicle is then converted into heat energy by kinetic friction of the rubbing surfaces and the car or truck slows down. 90003 90002 When vehicle comes to stop, it is held in place by static friction. The friction between surfaces of brakes as well as the friction between tires and roads resist any movement. To overcome the static friction that holds the car motionless, brakes are released. The heat energy of combustion of in engine is converted into kinetic energy by transmission and drive train, and the vehicle moves.90003 90002 90024 90003 90002 90011 Types of brakes 90012 90003 90002 There are basically three types of brakes used in automobiles 90003 90002 1. Mechanical brakes 90003 90002 2. Hydraulic brakes 90003 90002 3. Air Brakes and related type of brakes 90003 90002 90039 Mechanical brakes 90040 90003 90002 Mechanical brakes are used in Hand brakes (or parking brakes). Here, a lever is provided near the driver seat and through steel wire connections it is connected to brakes at the rear of the vehicle.90003 90002 When the hand brake is engaged, tension is created at the brakes and the brake shoe holds the drum from rotating and hence the movement of the vehicle is restricted, even if parked in a slightly inclined surface. 90003 90002 90039 Hydraulic brakes 90040 90003 90002 The hydraulic brake system uses brake fluid to transfer pressure from the brake pedal to the pads or shoe. By exercising the pedal, brake fluid transfers this pressure to the brake pads. This transfer of pressure is reliable and consistent because liquids are not compressible, i.e. pressure applied to liquid in a closed system is transmitted by the liquid equally to every other part of system. 90003 90002 90053 90003 90002 A hydraulic brake system apart from liquid pipes mainly consists of Brake pedal, Master cylinder, wheel cylinder and brake pads / shoe connected at the wheel. The function of the Master cylinder is to distribute pressure to lines leading to front or rear wheels as required. At the wheel cylinder, a small piston is provided which is operated due to pressure application through brake fluid.The operation of the piston is converted to movement of brake liners. 90003 90002 In brief, when a driver applies pressure at the brake pedal, the mechanical force (stepping of driver on pedal) is changed to hydraulic pressure which is transmitted through liquid to respective wheel cylinder and changed back to mechanical force (operation of brake pads, shoe). 90003 90002 Power Brakes 90003 90002 Power brakes are nothing more than a standard hydraulic brake system with a booster located between the brake pedal and master cylinder to help activate the brakes.This could be in case the fluid pressure required would be too high. 90003 90002 There are two basic types of power assisted mechanisms used, vacuum assisted and hydraulic assisted. 90003 90002 Vacuum assisted system use engine vacuum pressure to help apply the brakes. 90003 90002 Hydraulic assist is largely found on heavy vehicles. This system uses hydraulic pressure developed by the power steering pump or other external pump to help apply the brakes. 90003 90002 90039 Air 90040 90039 brakes 90040 90003 90002 Air brake system consist of components like air compressor, air reserve tank, check valves, safety valves etc.The working is very similar to the working of hydraulic brakes. The key difference is that mechanical force is transmitted to wheel ends through air pressure, instead of fluid pressure. Airbrakes are most preferred in heavy vehicles. 90003 90002 90011 Disc vs Drum Brakes 90012 90003 90002 Another brake classification is in terms of disc and drum. This refers to the actual mechanics of slowing down the vehicle. Let us take a look at these two systems. 90003 90002 90039 Drum brakes 90040 90003 90002 A drum brake assembly consists of a cast-iron drum which is bolted to and rotates with the vehicle’s wheel, and a fixed backing plate to which the shoes, wheel cylinder, automatic adjusters and linkages are attached.Additionally, there might be some extra hardware for parking brakes. 90003 90002 90090 90003 90002 The shoes are surfaced with friction linings, which contact the inside of drum when brakes are applied. The shoes are forced outward by piston located inside the wheel cylinder. As drum rubs against shoes, the energy of the moving drum is transformed to heat. This heat energy is passed into the atmosphere. When brake pedal is released, hydraulic pressure drops and the shoes are pulled back to their unapplied position by return springs.90003 90002 90039 Disc brakes 90040 90003 90002 In disc brakes the friction elements are in the form of pads, which are squeezed or clamped about the edge of a rotating wheel. With automotive disc brakes, there is a separate wheel unit called the Rotor (commonly called as 90011 disc) 90012 alongside the vehicle’s wheel. This rotor is made of cast iron. Since pads clamp against both sides of it, both sides are machined smooth. Usually the two surfaces are separated by a finned center section for better cooling (such rotors are called ventilated rotors or in common words as 90011 ventilated discs 90012).The pads are attached to metal shoes, which are actuated by pistons, the same as with drum brakes. 90003 90002 The pistons are contained within a caliper assembly, housing the wraps around the edge of the rotor. The caliper is kept from rotating by way of bolts holding it to the car’s suspension frame work. 90003 90002 90107 90003 90002 90110 90003 90002 Unlike shoes in a drum brake, the pads here act perpendicular to the rotation of disc when brakes are applied. The effect is different from that produced in a brake drum, where frictional drag actually pulls the shoe in to drum.Disc brakes are said to be non-energised and so require more force to achieve the same braking effort. For this reason, they are ordinarily used in conjunction with power brake unit. 90003 90002 In general, disc brakes are considered to be more effective than drum brakes. However, they are more complicated and hence come at a higher cost 90003 90002 90011 Stop Light Switches 90012 90003 90002 When exercising a brake, light starts burning on the back of the vehicle. The stop light switch and mounting bracket assembly is attached to the brake pedal bracket and is thus activated by pressing the brake pedal.90003 90002 90011 Brake bleeding 90012 90003 90002 Fluids can not be compressed, however gases are compressible. If there is any air in a fluid brake hydraulic system, this will be compressed as pressure increases. This action reduces the amount of force that can be transmitted by the fluid. This is why it is important to keep all bubbles out of the hydraulic system. To do this, air must be released from brakes. This procedure is called bleeding of brake system. 90003 90002 The simple procedure involves forcing of fluid through brake lines and out through a bleeder valve or bleeder screw.The fluid eliminates any air that may be in the system. Bleeder screws and valves are fastened to wheel cylinder or caliper. The bleeder must be cleaned. A drain hose is then connected from bleeder to glass jar where the fluid coming out from bleeder valve is collected. Bleeding involves repetition of procedure at each wheel to ensure complete bleeding. 90003 90002 Meanwhile, one person should also be assigned to top up the fluid level in container over master cylinder to compensate for the fluid taken out through valves.If top up is not continued, then there are chances of air bubbles being developed in system which further delays the process. 90003 90002 90011 Antilock Braking system 90012 90003 90002 When a driver quickly and firmly applies the brake and holds the pedal down, the brakes of a vehicle that is not equipped with ABS will almost immediately lock the wheels. The vehicle slides rather than rolls to a stop. During this time, the driver also has a difficult time keeping the vehicle straight and the vehicle might skid out of control.Here, the skidding and lack of control is caused by locking the wheels. If the driver could release the brake pedal just before the wheel locked up and then reapply brakes, the skidding could be avoided. 90003 90002 This last thing is exactly what an antilock system does. When the brake pedal is pumped or pushed, the pressure is quickly applied and released at the wheels. This is called 90011 Pressure Modulation. 90012 Pressure modulation works to prevent wheel locking. Antilock brake systems can modulate pressure to the brakes as often as 15 times per second.By modulating the pressure to brakes, the friction between tires and road is maintained and vehicle is able to come to a controllable stop. 90003 90002 Steering is another important consideration for the use of ABS. As long as a tire does not slip, it goes only in the direction in which it is tilted. But once it skids, it has little or no directional stability. One big advantage of ABS, therefore is the ability to keep control of vehicle under all conditions. 90003 90002 90011 Trouble shooting 90012 90003 90002 The table below gives the list of frequent troubles with brake systems, cause and remedy for the same.90003 90150 90151 90152 90153 90011 Sl no 90012 90156 90153 90011 Problem 90012 90156 90153 90011 Probable cause 90012 90156 90153 90011 Remedy 90012 90156 90169 90152 90171 1 90156 90171 Loss of brake efficiency 90156 90153 Oil soaked Brake drum / liner 90156 90153 Check and replace wheel cylinder, liners 90156 90169 90152 90153 Worn out brake lining 90156 90153 Replace 90156 90169 90152 90153 Defective master cylinder 90156 90153 Service / replace 90156 90169 90152 90193 2 90156 90193 Brake binding 90156 90153 Brake shoe retracting springs weak 90156 90153 Replace 90156 90169 90152 90153 Defective wheel cylinder 90156 90153 Replace 90156 90169 90152 90153 3 90156 90153 Brake overheating 90156 90153 As in brake binding and with prolonged usage 90156 90153 Replace 90156 90169 90152 90193 4 90156 90193 Brake Judder 90156 90153 Wrong brake adjustment 90156 90153 Adjust 90156 90169 90152 90153 Loose lining rivets 90156 90153 Replace 90156 90169 90152 90193 5 90156 90193 Vehicle pulling to one side 90156 90153 Improper adjustment of linings 90156 90153 Adjust 90156 90169 90152 90153 Oil or grease settled onliners 90156 90153 Replace 90156 90169 90152 90153 6 90156 90153 Hand brakes ineffective 90156 90153 Stretching of operating cable 90156 90153 Replace 90156 90169 90152 90153 7 90156 90153 Excessive loss of brake fluid 90156 90153 Leaking master cylinder or wheel cylinder or hose joints 90156 90153 Service / replace 90156 90169 90152 90153 8 90156 90153 Excessive air bubbles 90156 90153 Defective master cylinder 90156 90153 Replace 90156 90169 90280 90281 90002 90011 Conclusion 90012 90003 90002 Brake system is an important mechanism for usage of any vehicles.The above is an attempt to give the relevant information in as simple manner as possible. There are much technical concepts used in designing of brakes which is beyond scope of the article. All are welcome to post relevant queries and comments. We would answer the same. 90003.