Have you ever wondered how common things work, like a seatbelt? This article we found comes from How Stuff Works: Auto.
How Seatbelts Work
In a typical seatbelt system, the belt webbing is connected to a retractor mechanism. The central element is the retractor is a spool, which is attached to one end of the webbing. Inside the retractor, a spring applies a rotation force, or torque, to the pool. This works to rotate the spool so it winds up any loose webbing.
When you pull the web... read more