sir I want to about the knowledge in airbag and d
ownload in ppt file. santoshnahak[/size]
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ppt on air bags in cars for free download
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sir I want to about the knowledge in airbag and d
ownload in ppt file. santoshnahak[/size]
11-09-2015, 01:46 PM
ppt on air bags in cars for free download
An air bag is a safety feature designed to protect passengers in a head-on collision. Most cars today have driver's side airbags and many have one on the passenger side as well. Located in the steering wheel assembly on the driver's side and in the dashboard on the passenger side, the air bag device responds within milliseconds of a crash. After the initial impact, a folded nylon bag becomes rapidly inflated with nitrogen gas. This acts as a cushion for passengers, preventing them from hitting the steering column and dashboard, something that often causes traumatic injuries. While air bags have been around for awhile, their widespread use has only occured within the past decade. They have significantly reduced the number of deaths and serious injuries from automobile crashes. According to the Insurance Institute for Highway Safety, the number of deaths from collisions when both seatbelts and airbags were used was 24% less than when only seatblets were used. The National Highway Traffic and Safety Administration (NHTSA) now requires cars made after 1998 to contain both driver side and passenger air bags. This regulation and the popularity that air bags now enjoy from the safety conscious public mean that the air bag is a safety device that is here to stay.
How an Air Bag Works
The air bag system can be broken down into two main components. These are the impact sensor and the air bag module unit. The impact sensor does what its name implies, senses impacts. The sensors are set to a sensitivity level where they will only deploy in an accident that is equal to or greater than a 12 mph crash into a concrete wall. The sensors function by detecting automobile deceleration. When the automobile decelerates at a rapid rate, the sensors are tripped. This deceleration detecting is the job of two or more deceleration sensors, placed at the front of the car. When the sensors go off, they send an electrical current to the air bag module unit, causing it to deploy.
The air bag module unit consists of an inflator assembly, a nylon bag, and a breakaway cover. This unit is typically located in the steering wheel column on the driver's side or in the dashboard on the passenger's side. The electrical current from the sensors travels to the inflator assembly, where it causes a tiny initiator to be fired. This inititator creates a spark which ignites a propellant, which in most air bags is sodium azide. The reaction creates nitrogen gas. Cinders are removed and the gas is cooled through a filtration screen also inside the assembly. The nitrogen gas is what causes the air bag to inflate. This inflation occurs in an average of only 30 milliseconds. When an occupant plunges into the air bag, the gas if forced backwards through vents, a process which takes another forty-five milliseconds. The whole sequence from initial detection of a crash, until the air bag is fuly deployed, happends very quickly. This quickness is required in order to protect those inside of the car, and was one of the major obstacles that needed to be overcome in the development of the air bag.
When a car is speeding along at 50 Km per hour it has a tendency ('Inertia') to keep moving at the same speed and in the same direction unless some force acts on it. The car accelerates its occupants to its own speed so that they seem to be moving as a single unit. The inertia of the occupants is, however, independent of the inertia of the car. If the car were to crash into a tree, the force of the tree would bring the car to an abrupt halt. The speed of the occupants, however, would remain the same because of their independent inertia and they would bang into the steering wheel, the dashboard or the windshield. The force exerted by the steering wheel or the windshield would then bring the occupants to a stop but may in the process cause injury to vulnerable body parts such as the head and the face. Car manufacturers use 2 different restraint systems to help stop the occupants while doing as little damage to him or her as possible. The oldest and till now the most trusted device for restraining the passengers has been the seatbelt that spreads this stopping force across sturdier parts of the body over a longer period of time to minimize damage. The air bag is the second and a more recently developed system that is used to supplement the slowing down by the seat belt by deploying a rapidly inflating cushion in the space between the passenger and the steering wheel or dash board to prevent crash injuries. The Air Bag typically consists of the following 3 parts:
The bag itself is made of a thin, nylon fabric, which is folded into the steering wheel or dashboard or, more recently, the seat or door.
The sensor is the device that tells the bag to inflate. Inflation happens when there is a collision force equal to running into a brick wall at 10 to 15 miles per hour (16 to 24 km per hour). Sensors detect the crash using a mechanical switch that closes when a mass shifts and an electrical contact is made. Electronic sensors use a tiny accelerometer that has been etched on a silicon chip.
The air bag's inflation system uses the rapid pulse of hot nitrogen gas from the chemical reaction of sodium azide (nan3) and potassium nitrate (kno3) to inflate the bag.
The inflation system is not unlike a solid rocket booster. The air bag system ignites a solid propellant, which burns extremely rapidly to create a large volume of gas to inflate the bag. The bag then literally bursts from its storage site at up to 200 mph (322 kph) -- faster than the blink of an eye! A second later, the gas quickly dissipates through tiny holes in the bag, thus deflating the bag so you can move. Even though the whole process happens in only one-twenty-fifth of a second, the additional time is enough to help prevent serious injury.
An air bag is a safety feature designed to protect passengers in a head-on collision. Most cars today have driver's side airbags and many have one on the passenger side as well. Located in the steering wheel assembly on the driver's side and in the dashboard on the passenger side, the air bag device responds within milliseconds of a crash. After the initial impact, a folded nylon bag becomes rapidly inflated with nitrogen gas. This acts as a cushion for passengers, preventing them from hitting the steering column and dashboard, something that often causes traumatic injuries. While air bags have been around for awhile, their widespread use has only occured within the past decade. They have significantly reduced the number of deaths and serious injuries from automobile crashes. According to the Insurance Institute for Highway Safety, the number of deaths from collisions when both seatbelts and airbags were used was 24% less than when only seatblets were used. The National Highway Traffic and Safety Administration (NHTSA) now requires cars made after 1998 to contain both driver side and passenger air bags. This regulation and the popularity that air bags now enjoy from the safety conscious public mean that the air bag is a safety device that is here to stay.
How an Air Bag Works
The air bag system can be broken down into two main components. These are the impact sensor and the air bag module unit. The impact sensor does what its name implies, senses impacts. The sensors are set to a sensitivity level where they will only deploy in an accident that is equal to or greater than a 12 mph crash into a concrete wall. The sensors function by detecting automobile deceleration. When the automobile decelerates at a rapid rate, the sensors are tripped. This deceleration detecting is the job of two or more deceleration sensors, placed at the front of the car. When the sensors go off, they send an electrical current to the air bag module unit, causing it to deploy.
The air bag module unit consists of an inflator assembly, a nylon bag, and a breakaway cover. This unit is typically located in the steering wheel column on the driver's side or in the dashboard on the passenger's side. The electrical current from the sensors travels to the inflator assembly, where it causes a tiny initiator to be fired. This inititator creates a spark which ignites a propellant, which in most air bags is sodium azide. The reaction creates nitrogen gas. Cinders are removed and the gas is cooled through a filtration screen also inside the assembly. The nitrogen gas is what causes the air bag to inflate. This inflation occurs in an average of only 30 milliseconds. When an occupant plunges into the air bag, the gas if forced backwards through vents, a process which takes another forty-five milliseconds. The whole sequence from initial detection of a crash, until the air bag is fuly deployed, happends very quickly. This quickness is required in order to protect those inside of the car, and was one of the major obstacles that needed to be overcome in the development of the air bag.
When a car is speeding along at 50 Km per hour it has a tendency ('Inertia') to keep moving at the same speed and in the same direction unless some force acts on it. The car accelerates its occupants to its own speed so that they seem to be moving as a single unit. The inertia of the occupants is, however, independent of the inertia of the car. If the car were to crash into a tree, the force of the tree would bring the car to an abrupt halt. The speed of the occupants, however, would remain the same because of their independent inertia and they would bang into the steering wheel, the dashboard or the windshield. The force exerted by the steering wheel or the windshield would then bring the occupants to a stop but may in the process cause injury to vulnerable body parts such as the head and the face. Car manufacturers use 2 different restraint systems to help stop the occupants while doing as little damage to him or her as possible. The oldest and till now the most trusted device for restraining the passengers has been the seatbelt that spreads this stopping force across sturdier parts of the body over a longer period of time to minimize damage. The air bag is the second and a more recently developed system that is used to supplement the slowing down by the seat belt by deploying a rapidly inflating cushion in the space between the passenger and the steering wheel or dash board to prevent crash injuries. The Air Bag typically consists of the following 3 parts:
The bag itself is made of a thin, nylon fabric, which is folded into the steering wheel or dashboard or, more recently, the seat or door.
The sensor is the device that tells the bag to inflate. Inflation happens when there is a collision force equal to running into a brick wall at 10 to 15 miles per hour (16 to 24 km per hour). Sensors detect the crash using a mechanical switch that closes when a mass shifts and an electrical contact is made. Electronic sensors use a tiny accelerometer that has been etched on a silicon chip.
The air bag's inflation system uses the rapid pulse of hot nitrogen gas from the chemical reaction of sodium azide (nan3) and potassium nitrate (kno3) to inflate the bag.
The inflation system is not unlike a solid rocket booster. The air bag system ignites a solid propellant, which burns extremely rapidly to create a large volume of gas to inflate the bag. The bag then literally bursts from its storage site at up to 200 mph (322 kph) -- faster than the blink of an eye! A second later, the gas quickly dissipates through tiny holes in the bag, thus deflating the bag so you can move. Even though the whole process happens in only one-twenty-fifth of a second, the additional time is enough to help prevent serious injury.
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