Constant-force spring
George Emmott

A tightly coiled wound band of pre-hardened spring steel or stainless steel strip. When extended a constant force is exerted and this is maintained as the spring is allowed to close. The full force is effective until the spring is in the fully closed position.

This spring type derives its name from its ability to extend through its full working length while being maintained in any position by the same force. Constant force springs are available in a wide variety of sizes and the recent introduction of a purpose built plant ensures the price competitiveness of the smallest production run. Emmotts is one of the UK's most experienced manufacturers in this highly specialised field.