Seat Belts

Written by N.N

Source: http://scorpionautotech.com/wp-content/uploads/2014/05/seatbelts.jpg

Seat Belts keep the passenger from moving out of position and applies a force which stops the passenger moving forward.

Seat belts was first invented in the early 19th century by an English engineer named George Cayley but the first patent was granted to Edward J. Claghorn in 1885. The idea came from Dr Shelden in the early 1950's when his surgery became increasingly occupied with patients suffering from head injuries. Initially, the seatbelt was a 2 point belt system but then injuries such as the Seat Belt Syndrome became increasingly worse so Volvo introduced a three point system, which has since been used in majority of cars.

The work energy principle dictates that shorter stopping distances creates more impact force on the passenger. When a car crashes, the passengers are forced forwards due to inertia and momentum (Newton's second law) until the car hits a force that has equal kinetic energy, then the passengers move back into the seat (Newton's first law). Without the seatbelt, the passengers would be flung forwards into the windscreen and experience more injuries as they are still experiencing inertia and are moving at the same rate. The seatbelt is attached to car so when you put your seatbelt on, you become more attached to the you stop with the car and don't experience too much inertia in event of a car crash.

There have been many recent improvements over the last few years. An example of which is moving the seatbelt from being attached to the seat to being directly attached to the door. The list below outlines other recent improvements for seatbelts to increase passenger safety:

Webbing clamps: stop your seatbelt from reeling as it tightens on the spool, basically stops more seatbelt from coming out of the spool
Pretensioners: fast retraction of the belt to get rid of slack
Load limiters: releases webbing gradually so that it won’t harm the passenger as instant reeling would
Seat belt warning systems: tells the driver and passengers when the seat belt is not being worn

All these updates make our seatbelt system better and increase the effectiveness of this car safety feature. This is why it is important to wear a seatbelt; it saves lives!