Category: Automotive

Working of Disc Brakes in a Vehicle

The disc brake system converts the hydraulic pressure generated at the master cylinder into a frictional force against the rotating discs which is located on the wheel. Mostly modern vehicles have disc brakes on the front wheels and some have disc brakes on all four wheels. In this article let us discuss about the working of disc brakes in a vehicle.

Working of disc brakes in a vehicle
Before going to the working of a disc brake first let us know what are the components present in disc brake system. The disc brake system consist of a brake pedal or brake lever, a push rod,a master cylinder,piston, return springs, caliper assembly, brake pads and rotor / brake disc.

When a brake lever or pedal is pressed by the drivers foot, the push rod which is connected to brake pedal and master cylinder piston.

The push rod pushes the master cylinder piston. This movement allows the piston to slide and push the return spring which is located inside the master cylinder. The master cylinder acts as a brake booster. This movement generates the pressure in reservoir tank. This movement allows the brake fluid in the reservoir tank to flow into the brake hosepipes. A seal is equipped around the reservoir tank to make sure that the brake fluid does not go other side.

The brake fluid enters the cylinder of caliper assembly through brake hosepipes. This pressurized fluid pushes the caliper piston. The caliper piston may be one or more depending on the requirement. Then the caliper piston pushes brake pad. Now the brake pads sticks with brake disc, due to this process a friction is created between them and stops the brake disc/rotor to rotate. In this way the disk brake system stops the vehicle.

A lot of energy is absorbed while applying the brakes, so friction between braking parts generates heat. Brake parts are made of rigid material which can withstand very high temperatures. The friction surface of a disc is exposed to air for cooling. Unlike drum brakes, disc brakes throw off the water, when a vehicle is driven through water, they operate immediately. This is how the disc brakes normally works. Vented disc brakes are equipped with a set of vanes, between the two sides of the disc, used to pumps air through the disc to provide cooling.

Disc brakes need higher pressure to operate than drum brakes, for this a power brake booster is equipped to reduce the pedal forces that is applied by the driver. In some vehicles, drum brake is built into the center of the rear disc to provide parking brake operation.
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All About Automobile Steering

When the early automobiles came into existence, the main challenge with the manufacturers was to achieve the operational efficiency. The proper and reliable operation of the automobile was a challenge in itself and very less attention was put on areas like safety and convenience. Steering of car was one of the areas less focused on during the primitive designing of the car. Hence a rack and pinion steering was used that used primarily physical force to change the direction of motion of the car. It can still be seen in heavy duty vehicles like tractors where still physical rack and pinion steering is used. It involves a lot of physical force.

With time, the operational obstacle in cars was overcome and focus shifted towards convenience. Here came the era of power steering. Power steering uses hydraulic or electric motor actuator systems to sense the amount of force applied and magnification of force is done to achieve steering action. Consequently, steering action could be obtained by the use of minimal force.

Working of a traditional rack and pinion steering
A rack and pinion steering is the traditional and most widely used steering in cars and other automotive. This mechanism consists of a rod that has tie rods connected on both ends. A rack is provided on the rod and a pinion gear is mounted on the rack. This pinion gear connects the rack with the steering wheel. This arrangement is enclosed in a cylindrical tube on the rod. Deliberately, the rack is provided near one of the tires so that uniform turning of both the wheels alike does not happen. This is in all relation with the physics of automobile turning. Both the wheels of the vehicle should turn at different angles. The inner wheel is expected to take a smaller circle than the outer wheel for a smooth steer. When the driver rotates the steering wheel, the pinion gear on the rack turns which moves the rack rod in horizontal linear motions. The tie rod connecting the rack rod moves a steering arm on the spindle which turns the wheel for a steering action. The gear arrangement on the rack and pinion can be arranged for necessary ease and degree of motion required. This is how a rack and pinion steering mechanism works.

Working of power steering
Power steering is basically amplifier device that multiplies the manual force input of the driver to give necessary force to the rack and pinion arrangement for required amount of steering action. These amplifiers can be in the form of mechanical or electrical devices.

Hydraulic power steering
When we talk of mechanical amplifiers these are essentially hydraulic mechanisms. The power to reduce the human effort is derived from the engine power. When the steering is in neutral mode, fluid pressure on both sides of the piston will be equal and no movement will be there. During turning of the steering wheel on either side, the control valve operates which closes the fluid passage towards one side of the piston. This creates change in the forces and the gear arrangement over the rack and pinion moves as per the applied force giving the steering action.

Electrical power steering
In case of an electrical steering, a sensor senses the applied amount of force on the steering wheel and an electrical actuator activates an electrical motor that rotates the rack and pinion arrangement accordingly.

Future of power steering
Though power steering gives much relief to humans in terms of force that has to be applied, it affects the fuel economy as the power to turn the pinion arrangement is drawn from the engine power. In case of electrical power steering, the batteries that rotate the motors are charged with the engine power only. The future of the steering lies in electronic steering that will completely eliminate the mechanical connections of the steering wheel. We may expect joystick kind of electronic steering in the future that will actuate motor systems to obtain the steering actions.
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Working of Cooling System in Vehicles

Have you ever thought of how your engine cools? Or, how the cooling system of your car works? If you are interested to know how it works, it’s worth to read this article.

Inside your car hood air/fuel is constantly burnt due to which lot of heat from combustion goes out through the exhaust system, but some amount of heat remains in the engine, due to this the engine components heated up. If the heating of engine components happens continuously, the engine lifespan decreases. The engine runs effectively when coolant is at 200-230 degrees Fahrenheit.

Working of cooling system in vehicles
Cooling system in the vehicles are adopted to keep the engine from over heating by transferring the heat to atmosphere. When the engine is cold the components wear out and engine is less efficient and emits more pollutants,the coolant system allows the engine to heat up as quickly as possible and then keeping the engine at constant temperature.
The components of cooling system consists of :

  • Water pump
  • Engine
  • Thermostat
  • Radiator fans
  • Heater core
  • Pressure regulator
  • Radiator

We discuss how the cooling system works
A car engine produces a lot of heat when it’s running, and should be cooled continuously to avoid engine over heating. The engine is cooled by circulating water mixed with anti freezers. Some engines are cooled by air flowing through the air cooling fins.

A cooling passage is arranged around the engine block and cylinder head through which the coolant runs. At the top of the cylinder head all the coolant channels are converge to single passage.

A water pump, driven by a pulley and belt, drives hot coolant from the engine to the radiator,
The radiator acts as a heat exchanger, the hot coolant is passed through the radiator to the atmospheric air stream. The atmospheric air and the radiator fins absorb the coolant heat and the cooled coolant returns to inlet of water pump and again it flows back to the engine block and the cylinder head. The process thus continues.

The water pump sends coolant up through the engine and down through the radiator. The radiator is connected to the engine by rubber hoses, and has a top and bottom tank connected by many fine tubes.
These tubes pass through the radiator fins and lose heat rapidly to the cooler air passing through the radiator fins.
The extra pressure of coolant is regulated by the radiator cap, which is equipped with a pressure valve in it. Excess pressure in the system can be removed by opening the pressure regulator valve.
With a cooling system of this type, there is a continual loss of coolant if the engine runs very hot.
Most vehicles are equipped with water-cooled cooling system, because it’s more effective than the air-cooled cooling system.
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How to Change the Flattened Tire of Your Car

When you are driving you may face a situation: your car tire become flattened, which might be because of diverse reasons. The solution at the moment is to replace the flattened tire with another one, which you are likely to have.

Do you want to change the tire without asking anyone’s help. The changing of tire is a simple task, provided you are prepared and willing to put some effort.

We’re going to discuss the step to be followed to change the flat tire of your car. Follow are simple steps to fix the problem:

How to change flat tire of your car

  • Find a safe spot to remove the flattened tire
    • When your driving your car on an highway or city roads if the car tire suddenly blasted find a safe spot for parking your car even if you have to drive on a blown tire.
    • You can also pull your car as far onto the shoulder as possible to avoid traffic jam or some other issues by parking in middle of the road..
    • Don’t park in the middle of a turning where approaching cars can’t see you.
    • Also, choose a level spot; jacking up your car on a hill can cause dangerous issues.
    • If you have a manual transmission, leave your car in gear.
    • Make sure that your parking brake set in “On” condition
  • Turn “on”hazard lights while you are yet to start replacing flat tires
    • Before starting turn “On” your hazards lights.
    • Get the jack, wrench, and spare tire from the rear trunk of the car and bring them near to the flat tire. Use other tools if required.
  • Use the wrench to loosen the nuts
    • Firstly you need to remove the hubcap.
    • Don’t remove the lug nuts simply loosen them by turning the wrench to the counter-clockwise direction.
    • If the lug nuts are very tight try placing them with wrench on the nut and stand on the wrench arm to use your full weight to loosen lug nut.
    • You can also try hitting the wrench arm with a stone, that you can find from around.
  • Use the jack to lift the vehicle from the ground level
    • Different car models may have different places to put the jack.
    • Before lifting the vehicle go through your owner’s manual for finding the exact position.
    • Once the jack is in the correct spot, lift the car until the tire is above the ground level.
    • Lift the vehicle until you fill comfortable for changing the flat tire.
  • Remove the lug nuts and pull off the tire from the car
    • Remove the lug nuts. Make sure to place the lug nuts in a safe area so that you won’t misplace them. Pull the tire and remove it from the wheel base.
  • Fix the new tire on to the wheel base
    • After removing all the fasten parts fix the new tire to the wheel base.
  • Place spare tire on the car
    • Reconnect the lug nut posts with the holes in the spare tire.
    • Push the spare tire all the way onto the wheel base until it can’t go any farther.
  • Reconnect the lug nuts
    • Reconnect the lug nuts
    • Don’t fix them on tightly, just make sure they’re on enough for the spare to stay on the car for a moment.
  • Lower the car back to the ground
    • Use the jack to bring the car down to ground level.
    • Remove the jack from underneath the car.
  • Make sure the lug nuts are tightened
    • You can now tighten the lug nuts.
    • Rather than tightening them one by one in order, start with one lug nut, tighten it about 50% move to the opposite nut and tighten that one about the same amount.
    • Keep tightening opposite lug nuts in turn until each lug nut is as tight as it can be.
  • Put your flat tire and tools back in your trunk
    • After tightening all the required components Put the flat tire and tools back into the rear trunk. Make sure that you don’t leave anything on the side of the road.

 

Types of Car Batteries and Their Advantages

Are you confused which type of battery to choose for your car? To get you out of this confusion we have created this article that provides the various types of car batteries and their advantages. Every battery has its own advantage and you need to determine which suits best for your car. Some of the batteries that can be used for your car are:

Flooded or wet cell battery: This is one of the most popular battery type available in the market today and it costs less. These batteries come in various sizes and shapes. Maintenance of this batteries is very easy and gases are not replaced. You don’t have to keep topping this batteries as the fluid in it lasts until the battery dies. The price of the battery varies based on the brand that you choose.

Lithium ion battery: These batteries are designed especially for hybrid electric cars. The lithium ion batteries are power packed. These batteries store more energy in small space available than the traditional batteries. Lithium is the metal which gives stamina to the batteries as it has the most energy density and electrochemical potential. As they are slim and compact, installation is very easy. This makes the car body free in designing.

Rechargeable liquid battery: These batteries are designed for electric vehicles and the energy here is stored in the form of liquid. These are recharged just like traditional batteries or by pumping fuel. The materials in the rechargeable batteries helps in traveling long distance which will be five time more than electric vehicles today. The challenges with the electric cars like long recharge time and limited range of driving are achieved with this rechargeable liquid or electrode batteries.

Deep cycle battery: These batteries provide power for a long time for the car. These batteries are used mostly for electric vehicles and you can also use these batteries to store solar or wind power. But, this is not used for cars that travels long because they discharge the power quickly. These batteries are really very expensive and not much recommended for cars.

Calcium-calcium battery: These batteries are made of calcium alloys on differently charged plates which reduces the fluid loss. These batteries are maintenance free and are highly performed batteries. These batteries have increased life time if they are properly charged and not overcharged.

Choose a battery for for your car according to the its requirements.
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