Canted coil springs: what they are and how they work
July 30, 2021
- canted coil spring
- spring finger
- contacts
A canted coil spring, also known as an oblique or inclined coil spring or a spring finger contact, can transmit strong current in a small space and can also be used as a simple mechanical connection. It places no special constraints on how it is used and suits a variety of static and dynamic medium- and high-voltage environments. The size of the spring fingers and the number of independent coil turns make the spring suitable for many electrical contact designs and for electrical or EMI shielding applications that need a large current-carrying capacity at the contact point.
How the canted coil spring works
Each coil independently compensates for contact and surface variations, which allows a wider range of tolerances between mating parts. Multiple contact points add conductivity, and because the operating temperature of the contact is relatively low, service life is longer. The canted coil spring is used for power contact in a variety of industries, including medical electronics, medical devices, aerospace and defense, energy and automotive.
Main advantages
First, the structure is simple, the part is small and light, uses little material and costs little, which suits the small space available in compact equipment, keeps the number of components low and simplifies the design of the connecting device. Second, multi-point contact with high contact concentration achieves nearly loss-free contact, ensuring a large current-carrying capacity, good conductivity and high electrical and thermal stability. Third, the contact pressure at each point is low, giving good wear resistance. Fourth, the common structure provides a wide working range, permits large tolerances on the contact surface, adapts well to machining and assembly errors and suits large-scale production.
Typical applications
Typical uses include high- and medium-voltage switchgear, busbar connectors, high-current connectors, solid terminal posts, high-voltage end fittings, fuse connectors and mechatronic applications.
