09-04-2011, 04:57 PM
presented by
HAREESH KUMAR
[attachment=11963]
“AIR BAGS IN AUTOMOBILES”
INTRODUCTION
Seat belts have been proven to be effective in saving lives and preventing or lessening injuries in automobile accidents. The key to their success, however, is that occupants must use these safety devices. Because seat belts require active use by the wearer, inventors developed passive restraints to ensure driver and passenger safety. The first passive restraints were modifi-cations of seat belts themselves; the belts were coordinated with operations of opening the car doors and starting the au-tomobile, which caused belts built into tracks in the doors to wrap around the driver or passenger when the seat was occu-pied. Concurrently, the airbag was devised as a secondary form of passive restraint during impact.
TerminologyOf Airbags
Because no action by the vehicle occupant is required to acti-vate or use the airbag, it is considered a passive device. This is in contrast to seat belts, which are considered active devices because the vehicle occupant must act to enable them. Note that this is not related to active and passive safety, which are, respectively, systems designed to prevent accidents in the first place and systems designed to minimize accidents once they occur. For example, the car's Anti-lock Braking System will qualify as an active-safety device while both its seatbelts and airbags will qualify as passive-safety devices. Further termino-logical confusion can arise from the fact that passive devices and systems — those requiring no input or action by the ve-hicle occupant — can themselves operate in an active manner; an airbag is one such device. Vehicle safety professionals are generally careful in their use of language to avoid this sort of confusion, though advertising principles sometimes prevent such syntactic caution in the consumer marketing of safety features.
Various manufacturers have over time used different terms for airbags. General Motors' first bags, in the 1970s, were mar-keted as the Air Cushion Restraint System(ACRS). Common terms in North America include Supplemental Restraint System(SRS) and Supplemental Inflatable Restraint (SIR); these terms reflect the airbag system's nominal role as a supplement to active restraints, i.e., seat belts.
INVENTION
An American inventor, John Wenrick, a retired industrial engineer, designed the original safety cushion for automotive use in 1952 at his kitchen table. His patent lasted only 17 years - long before mainstream automotive usage.
Dr. David S. Breed, invented and developed a key component for auto-motive use: the ball-in-tube inertial sensor for crash detection. Breed Corporation then marketed this innovation first in 1967 to Chrysler. A similar "Auto-Ceptor" crash-restraint, developed by Eaton, Yale & Towne Inc. for Ford was soon offered as an automatic safety system in the USA, while the Italian Eaton-Livia company offered a variant with localized air cushions.
Airbags for passenger cars were introduced in the United States in the mid-1970s, when seat belt usage rates in the country were quite low. Ford built an experimental fleet of cars with airbags in 1971, followed by General Motors in 1973 on Chevrolet vehicles. The early fleet of ex-perimental GM vehicles equipped with airbags experienced seven fatalities, one of which was later suspected to have been caused by the airbag.
In 1974, GM made the "Air Cushion Restraint System"(ACRS) available as a regular production option (RPO code AR3) in some full-size Buick, Cadillac and Oldsmobile models. The GM cars from the 1970s equipped with ACRS have a driver side airbag, a driver side knee restraint (which consists of a padded lower dashboard) and a passenger side airbag. The passenger side airbag, protects both front passengers and unlike most newer ones, it integrates a knee cushion, a torso cushion and it also has dual stage deployment which varies depending on the force of the impact. The cars equipped with ACRS have lap belts for all seating positions but they do not have shoulder belts. These were already mandatory equipment in the United States on closed cars without airbags for the driver and outer front passenger seating positions.
The automotive industry's first passenger side knee airbag (not sepa-rate) was already used on the 1970s General Motors cars, it was inte-grated in the passenger airbag that had a knee cushion and a torso cushion.
Manufacturers emphasise that an airbag is not, and can not be an al-ternative to seatbelts. They emphasise that they are only supplemental to a seatbelt. Hence the commonly used term "Supplemental Restraint System"(SRS). It is vitally important that drivers and passengers are aware of this. In the majority of cases of death caused by air bags, seat belts were not worn.
Airbags As a Supplemental Restraint System(SRS)
Frontal airbag
The auto industry and research and regulatory communities have moved away from their initial view of the airbag as a seat belt replace-ment, and the bags are now nominally designated as Supplemental Restraint System (SRS) or Supplemental Inflatable Restraints.
In 1980, Mercedes-Benz introduced the airbag in Germany as an option on its high-end S-Class (W126). In the Mercedes system, the sensors would automatically pre-tension the seat belts to reduce occupant's motion on impact (now a common feature), and then deploy the airbag on impact. This integrated the seat belts and airbag into a restraint system, rather than the airbag being considered an alternative to the seat belt.
In 1987, the Porsche 944 turbo became the first car in the world to have driver and passenger airbags as standard equipment. The Porsche 944 and 944S had this as an available option. The same year also saw the first airbag in a Japanese car, the Honda Legend.
Audi was relatively late to offer airbag systems on a broader scale; until the 1994 model year, for example, the 80/90, by far Audi's 'bread-and-butter' model, as well as the 100/200, did not have airbags in their standard versions. Instead, the German automaker until then relied solely on its proprietary procon-ten restraint system.
During the 2000s side airbags were commonplace on even budget cars, such as the smaller-engined versions of the Ford Fiesta and Peugeot 206, and curtain airbags were also becoming regular features on mass market cars. The Toyota Avensis, launched in 1998, was the first mass market car to be sold in Europe with a total of nine airbags. Although in some countries, such as Russia, airbags are still not standard equipment on all cars, such as those from Lada.
Variable force deployment front airbags were developed to help minimize injury from the airbag itself.
SHAPED AIRBAGS
The Citroën C4 provides the first "shaped" driver airbag, made possible by this car's unusual fixed hub steering wheel.
HAREESH KUMAR
[attachment=11963]
“AIR BAGS IN AUTOMOBILES”
INTRODUCTION
Seat belts have been proven to be effective in saving lives and preventing or lessening injuries in automobile accidents. The key to their success, however, is that occupants must use these safety devices. Because seat belts require active use by the wearer, inventors developed passive restraints to ensure driver and passenger safety. The first passive restraints were modifi-cations of seat belts themselves; the belts were coordinated with operations of opening the car doors and starting the au-tomobile, which caused belts built into tracks in the doors to wrap around the driver or passenger when the seat was occu-pied. Concurrently, the airbag was devised as a secondary form of passive restraint during impact.
TerminologyOf Airbags
Because no action by the vehicle occupant is required to acti-vate or use the airbag, it is considered a passive device. This is in contrast to seat belts, which are considered active devices because the vehicle occupant must act to enable them. Note that this is not related to active and passive safety, which are, respectively, systems designed to prevent accidents in the first place and systems designed to minimize accidents once they occur. For example, the car's Anti-lock Braking System will qualify as an active-safety device while both its seatbelts and airbags will qualify as passive-safety devices. Further termino-logical confusion can arise from the fact that passive devices and systems — those requiring no input or action by the ve-hicle occupant — can themselves operate in an active manner; an airbag is one such device. Vehicle safety professionals are generally careful in their use of language to avoid this sort of confusion, though advertising principles sometimes prevent such syntactic caution in the consumer marketing of safety features.
Various manufacturers have over time used different terms for airbags. General Motors' first bags, in the 1970s, were mar-keted as the Air Cushion Restraint System(ACRS). Common terms in North America include Supplemental Restraint System(SRS) and Supplemental Inflatable Restraint (SIR); these terms reflect the airbag system's nominal role as a supplement to active restraints, i.e., seat belts.
INVENTION
An American inventor, John Wenrick, a retired industrial engineer, designed the original safety cushion for automotive use in 1952 at his kitchen table. His patent lasted only 17 years - long before mainstream automotive usage.
Dr. David S. Breed, invented and developed a key component for auto-motive use: the ball-in-tube inertial sensor for crash detection. Breed Corporation then marketed this innovation first in 1967 to Chrysler. A similar "Auto-Ceptor" crash-restraint, developed by Eaton, Yale & Towne Inc. for Ford was soon offered as an automatic safety system in the USA, while the Italian Eaton-Livia company offered a variant with localized air cushions.
Airbags for passenger cars were introduced in the United States in the mid-1970s, when seat belt usage rates in the country were quite low. Ford built an experimental fleet of cars with airbags in 1971, followed by General Motors in 1973 on Chevrolet vehicles. The early fleet of ex-perimental GM vehicles equipped with airbags experienced seven fatalities, one of which was later suspected to have been caused by the airbag.
In 1974, GM made the "Air Cushion Restraint System"(ACRS) available as a regular production option (RPO code AR3) in some full-size Buick, Cadillac and Oldsmobile models. The GM cars from the 1970s equipped with ACRS have a driver side airbag, a driver side knee restraint (which consists of a padded lower dashboard) and a passenger side airbag. The passenger side airbag, protects both front passengers and unlike most newer ones, it integrates a knee cushion, a torso cushion and it also has dual stage deployment which varies depending on the force of the impact. The cars equipped with ACRS have lap belts for all seating positions but they do not have shoulder belts. These were already mandatory equipment in the United States on closed cars without airbags for the driver and outer front passenger seating positions.
The automotive industry's first passenger side knee airbag (not sepa-rate) was already used on the 1970s General Motors cars, it was inte-grated in the passenger airbag that had a knee cushion and a torso cushion.
Manufacturers emphasise that an airbag is not, and can not be an al-ternative to seatbelts. They emphasise that they are only supplemental to a seatbelt. Hence the commonly used term "Supplemental Restraint System"(SRS). It is vitally important that drivers and passengers are aware of this. In the majority of cases of death caused by air bags, seat belts were not worn.
Airbags As a Supplemental Restraint System(SRS)
Frontal airbag
The auto industry and research and regulatory communities have moved away from their initial view of the airbag as a seat belt replace-ment, and the bags are now nominally designated as Supplemental Restraint System (SRS) or Supplemental Inflatable Restraints.
In 1980, Mercedes-Benz introduced the airbag in Germany as an option on its high-end S-Class (W126). In the Mercedes system, the sensors would automatically pre-tension the seat belts to reduce occupant's motion on impact (now a common feature), and then deploy the airbag on impact. This integrated the seat belts and airbag into a restraint system, rather than the airbag being considered an alternative to the seat belt.
In 1987, the Porsche 944 turbo became the first car in the world to have driver and passenger airbags as standard equipment. The Porsche 944 and 944S had this as an available option. The same year also saw the first airbag in a Japanese car, the Honda Legend.
Audi was relatively late to offer airbag systems on a broader scale; until the 1994 model year, for example, the 80/90, by far Audi's 'bread-and-butter' model, as well as the 100/200, did not have airbags in their standard versions. Instead, the German automaker until then relied solely on its proprietary procon-ten restraint system.
During the 2000s side airbags were commonplace on even budget cars, such as the smaller-engined versions of the Ford Fiesta and Peugeot 206, and curtain airbags were also becoming regular features on mass market cars. The Toyota Avensis, launched in 1998, was the first mass market car to be sold in Europe with a total of nine airbags. Although in some countries, such as Russia, airbags are still not standard equipment on all cars, such as those from Lada.
Variable force deployment front airbags were developed to help minimize injury from the airbag itself.
SHAPED AIRBAGS
The Citroën C4 provides the first "shaped" driver airbag, made possible by this car's unusual fixed hub steering wheel.
