Spiral Springs

These are generally made of rectangular section material, flat strip, with round edges or normal slit edges with equal or increasing space between coils. These are wound flat to achieve torque. For first 3600, torque delivered per revolution is linear. Therefore, these are generally used for less than 3600 rotational applications. If the these springs are totated more than one turn the coils will touch each other causing friction leading to erratic loads.

These are general used as brush springs in D.C. mortors, anti-backslash springs, Alternators, Drill presses, Vertical mill, Counter balance springs etc.