In: Mechanical Engineering
The spiral spring used in a clock used as a spring.
A clock spring is used inside the steering of a car. It is used to connect the horn and other switches and controls mounted on the steering wheel. It is just e ribon containing simple conductors. But it looks like the spiral spring of a clock. Though it is 12 foot long, but still it is not sufficient to turn the steering sheel infinitely.So, somewhere it restricts the movement of steering wheel. Which maybe a reason to call it as a spring.
A spring must store energy and release it, which is called as a restoring force in definition. But clock spring of a steering wheel has none of the properties which a spring should have. Still it is called as spring due to its shape, which is very similar to the spring of a clock.
Google it for better visuals. Sorry for bad drawing