Constant Force

Constant Force springs are a special variety of extension springs. They consist of strip material with built-in curvature so that each turn of the strip wraps tightly on itself. When the strip is extended (deflected) the inherent stress resists the loading force at a nearly constant (0) rate. This property allows the Constant Force springs to provide uniform force over a long period of travel. Constant Force springs are well suited for long extensions with no load build-up