Braking System

We all have fun pushing down on the brake pedal which slows a car to stop. But many are not aware that, how does it happens? Do you know how does your car transmit the force from your leg to the wheels? How does it multiply the power so that it is sufficient to stop something as big as a car? In this section we are aiming to give information about brake system, we would follow the chain of events from the pedal to wheel, and explaining all the parts of brake system. It also contains information on parking brake cable and brake lever.
Brake
Brake Drum
Brake Hose
Brake Pedal
Parking Brake Cable
Parking Brake Lever
Types of Brake System

Brake

Brake is an equipment used in automobiles or machines to slow down a running object by changing the kinetic energy into heat energy. Brake is used to stop an object or equipment that is running.
Brakes generally apply friction to change the kinetic energy into heat energy, however in renewing brake the kinetic energy is changed into useful electrical energy or potential energy which is in type of pressurized air as an alternative to heat energy.
The brakes in automobile stores the heat in the drum brake or disc brake while braking then carry out it to the air regularly. When traveling downward few automobiles use its engine to brake.
When brake is pushed the caliper holding the piston pushes the pad near brake disc to slow down the wheels of automobile. On brake drums it is same as the cylinder pushes the brake shoes to the drum which slows the wheels of the automobile.

Brake Drum

The Brake Drum is very heavy flat-topped cylinder that is usually sandwiched between the wheel rim and the drive wheel. The inside exterior of the drum is acted upon by the friction fabric of the brake shoes. When the brakes are functional, the friction material of the brake shoes is forced into contact with the brake drums to measure the rotation of the wheels. The friction connecting the tires and the road surface then slows the car's speed. Drum brakes are found on the rear wheels of most cars, but they are ever more being phased out in favor of rear disc brakes. Drum brakes were normal equipment on the front wheels of most cars until the early 70's.

Brake Hose

The master cylinder is associated to each wheel by brake lines and hoses. Brake hoses are specially constructed elastic tubes with metal ends for transmitting fluid under extreme pressure. The entire hydraulic system is filled with a particular brake fluid, which is forced through the hoses by the association of the master cylinder's pistons. If they appear cracked or brittle, the hoses must be replaced immediately. Close inspection of the brake hoses is a high-quality way to prevent catastrophe!


Brake Pedal
 

The brake pedal is placed on the left side of the accelerator pedal. Stepping on this pedal begins the process of slowing down or may stopping a vehicle. The pedal is solidly mounted to the firewall, and the works as a force-multiplying lever. If the power assist fails, the pedal's leverage is intended to allow the driver to still generate thousands of pounds of force at each wheel cylinder.

Attached to the piston within the master cylinder via a pushrod, the brake pedal is a majority important item indeed, unless you're a crash dummy! When the brake pedal is pressed, the brake shoes and the friction pads are forced into contact with the brake drums and rotors to measure the rotation of the wheels. The friction between the tires and the road surface then slows the pace of the vehicle. A brake pedal must not sink more than an inch or two, no matter how hard it is pushed with the foot; and the driver should not feel as if he were stepping on a wet sponge: a spongy pedal spells difficulty in the braking system. ANY change in the "feel" of your brake pedal must be a cause for serious concern. With brakes, there is no excuse for the poor maintenance.

Parking Brake Cable

 

The Parking Brake Cable is a brake cable in the parking brake is typically changeable for length which is made of steel. Parking brake cable is connected directly to the brake device on one end and another end is connected to the brake lever of the rear wheels that is activated by the driver. When brake lever is pulled, it transmits the force to the brake system. The force is transmitted by the brake fluid which runs through the cable. In automobiles with rear drum brakes, the parking brake cable regularly activates these drums mechanically with less force than is available through the hydraulic system.
Parking brake cables are available in different sizes like 1/8", 3/16" and also in custom designs. 1/8" brake cable is designed and produced for used in light to medium duty automobiles. These cables are used at 1,200 pounds or less. 3/16" brake cables provide the similar traits as the 1/8" brake cables. This 3/16" brake cable is suggested for higher load up to 3,000 pounds.

Parking Brake Lever

The Parking Brake Lever in automobiles is a hand activated system which is also called as hand brake. In cars the parking brake lever is like a handle on the bottom among the driver and front seat passenger. It is less commonly a handle bar placed on the bottom of the dashboard near to the steering wheel or between the driver and car door. Otherwise the lever is on the bottom in the form of pedal in front of the driver which is positioned to the far left separated from the other pedals.
In buses the parking brake lever is outfitted with a hydraulic brake system will have a hand brake lever which is situated on the driver left side near to the floor. It is activated by pushing the lever down with hand to apply the brake, and pulling it upwards to free the brake.
In large vans when the parking brake lever is pulled it will activate a valve that lets air or hydraulic pressure or vacuum into the cylinder which provides power to the brake shoes and makes applying the handbrake easier. In many cases a little lever in the automobile is coupled to a valve which admits air to parking brake cylinders to discharge the parking brake, or discharge the air to apply the brake. In some recent automobiles the valve is activated electrically from a lever in the automobile.

Types of Brake System

Air Brake System
Air Brake System is the brake system used in automobiles such as buses, trailers, trucks, and semi-trailers. George Westinghouse created air brakes for utilizing it in trains for railway service. A secured air brake was patented by him on 5th, March 1872. At first air brake is produced for use on trains and now it is used common in automobiles.

Anti-lock Brake System
An Anti-lock Braking System abbreviated as ABS is a braking system or security system which prevents the wheels on an automobile from locking up while braking. The wheels revolving on the road let the driver to maintain steering control under heavy braking by preventing a skid and allowing the wheel to continue interacting tractively with the road surface as directed by driver steering inputs.

Disc Brake
Disc Brake is a brake device for stopping or slowing the rotation of the automobile wheels. It is also called as Disk brake. This brake has a brake disc which is also called as rotor is made up of cast iron or ceramic compounds like carbon, Kevlar and silica is linked to the wheel and/or the axle.

Drum Brake
Drum Brake is a brake in which the friction is caused by a set of brake pads or brake shoes that push against the inner surface of a rotating drum. The drum is coupled to a rotating wheel. The drum brake was invented by Louis Renault in 1902.

Hydraulic Brake
The Hydraulic Brake system is a braking system which uses brake fluid usually includes ethylene glycol, to transmit pressure from the controlling unit, which is usually near the driver, to the actual brake mechanism, which is near the wheel of the vehicle. 

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Transmission

What is a transmission

The transmission is a device that is connected to the back of the engine. It transmits mechanical power from the engine to the drive wheels. The transmission is used to reduce the revolutions of the crankshaft down to a reasonable value by using interlocking gears to reduce the number of revolutions. By doing so, it makes more effective usage of the engine's torque and helps to keep the engine operating at an appropriate speed. 

Common types of Transmission  

• Manual transmission

• Automatic transmission

• CVT (Continuous variable transmission) 

• Semi automatic transmission

• TipTronic gearbox

• DSG (Direct shift gearbox)       

Manual transmission

Most manual transmissions feature a movable gear selector and clutch. The driver of the vehicle has to manually select and engage the gear ratios. The clutch is a coupling device that is used to separate the engine and transmission. Without it, the engine would stop, causing the vehicle to stop. The clutch allows the engine to continue working when you are waiting at the traffic light. Changing gear without a clutch would be difficult with the crank spinning continuously while the engine is running.

Automatic transmission

                                                                                                                                                                         

An automatic (also called automatic gearbox, or auto transmission) is one type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually. Most automatic transmissions have a defined set of gear ranges, often with a parking pawl feature that locks the output shaft of the transmission.

Similar but larger devices are also used for heavy-duty commercial and industrial vehicle and equipment.Some machines with limited speed ranges or fixed engine speeds, such as some forklifts and lawn mowers, only use a torque converter to provide a variable gearing of the engine to the wheels.

CVT  (Continuously Variable Transmission)

So, you looked at the picture provided and mistook it for the conventional automatic transmission. That had to happen as there is not much of difference between the two. So firstly, let me tell you what is the main difference between a CVT and conventional automatic transmission? The conventional automatic transmission has fixed ratios while the CVT doesn’t. The drive in the CVT goes through two variators and a V shaped steel belt. And the ratios are electronically held according to the throttle position and load on the engine.

Usually in the normal gearbox or any other automatic gear box whenever the car accelerates, it makes noise accordingly. But a CVT equipped car will not make a sudden change in the noise because the CVT holds the engine at the best possible rate for acceleration. But generally CVT’s are not advised for high speed as it will deter its fuel efficiency. Reason being they consume the hydraulic power. Also, the amount of torque is limited. Actually this all is because of the fact that everything is totally dependent on the amount of friction between belt and variators. But on the positive side, CVT’s makes less noise. They are much more compact than the conventional automatic gearshift, hence they take less space. It also improves the ride quality.

Semi automatic transmission

A semi-automatic transmission (also known as automated transmission, self-changing transmission, clutchless manual transmission, automated manual transmission, flappy-paddle gearbox, or paddle-shift gearbox) is an automobile transmission that does not change gears automatically, but rather facilitates manual gear changes by dispensing with the need to press a clutch pedal at the same time as changing gears. It uses electronic sensors, pneumatics, processors and actuators to execute gear shifts on the command of the driver or by a computer. This removes the need for a clutch pedal which the driver otherwise needs to depress before making a gear change, since the clutch itself is actuated by electronic equipment which can synchronise the timing and torque required to make quick, smooth gear shifts. The system was designed by automobile manufacturers to provide a better driving experience through lightning fast overtaking maneuvers on highways.

Tiptronic

These are one of the most underdog types of transmissions. Why so? Because, these types of transmissions are amongst the costliest transmissions and hence, rare because of the same reason (cost).  Usually, in order to change the gear, what does a driver do? First he gets hold of the clutch and then pulls the gear shift to the next level, right? But when we talk about the Tiptronic gear shift, one doesn’t have to do all that. The clutch in the car fitted with a Tiptronic gear shift is automatic. So, one has to only use throttle in order to increase the speed. But what the driver has to do actually? All a driver has to do in order to change the gear in such type of transmission is push the gear selector forward for up-shift and downward for downshift. Now the advantage of a Tiptronic gear shift over the other automatic gear shifts is that, it tends to give more power in the hands of the driver. This more power is a result of the result of more control. Just imagine, ended are those fuzzy days when you had to struggle with the transmission option available in your normal car as now the Tiptronic gear shift is here. Now lets come back to reality and face the heat that this type of transmissions are way above costlier than the any other automatic transmission (at least the cars with Tiptronic gear shifts are). If you really want to know how this gear shift looks like then I’m afraid you have to be satisfied with the picture illustration we have provided until and unless your dad is a millionaire. Anyways, this type of gear shift could be found inside Volvo S80. To add to the “aww”, this gear shift also has a feature wherein, just by shifting maps in the control unit, the gear shift will automatically shift according to the style of driving.

DSG (Direct shift gearbox) 

A direct-shift gearbox (German: Direkt-Schalt-Getriebe), commonly abbreviated to DSG, is an electronically controlled dual-clutch multiple-shaft manual gearbox, in a transaxle design – without a conventional clutch pedal, and with full automatic, or semi-manual control. The first actual dual-clutch transmissions derived from Porsche in-house development for 962 racing cars in the 1980s.

In simple terms, a DSG is two separate manual gearboxes (and clutches), contained within one housing, and working as one unit. It was designed by BorgWarner,  and was initially licensed to the Volkswagen Group, with support by IAV GmbH. By using two independent clutches, a DSG can achieve faster shift times, and eliminates the torque converter of a conventional epicyclic automatic transmission.

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