What is a Canted Coil Spring?

Canted coil springs (also known as cant or slant coil springs) are not your typical spring, and this becomes obvious when you take a look at the three different types of tasks they support:

• Acting as a mechanical connector
• Energizing seals for better performance
• Providing EMI/RFI shielding
• Serving as a multiple contact point conductor

All of these functions serve a wide variety of industries, including those that deal with medical and surgical devices.

Mechanical Connectors

Canted coil springs can provide a reliable connector in three different ways: holding and retaining two parts in alignment with a highly controlled sliding force, securely latching two parts together while allowing them to still be unlatched, and even permanently locking two parts together. Canted coil springs accomplish all of this with high precision, reliability, and strength. As a result, one interesting application of canted coil springs as connectors involves locking together the frame assembly on a ventilator cart.

Spring-Energized Seals

One of the features that sets canted coil springs apart from more traditional coil springs lies in their ability to provide far more consistent spring load values over a wide range of displacements. Because of this, they are often used as energizers for seals that need to maintain their performance even in the presence of eccentric or uneven contact surfaces, runout, or hardware gaps. Such reliable, high-performance seals find many types of medical and surgical equipment.

EMI/RFI Shielding for Critical Medical Equipment

Electromagnetic and radio frequency interference can be very dangerous for medical equipment, having the potential to disrupt its normal operation or comprise the integrity of data transmitted or received. For this reason, you will often find canted coil springs in electrical enclosures or used with data transmission cables. These springs can be customized and tuned to meet impedance specifications to protect equipment from crosstalk interference.

Multiple Contact Point Conduction

Canted coil spring assemblies are already being used in active implantables such as neurostimulators and pacemakers. The designs for these implantables depend on the multiple electrical contact points provided by canted coil springs. These springs make possible a consistent electrical connection between the battery and the lead, and do so within one of the most challenging operating environments: the human body.

Conclusion

Whether they are used to hold the framework of a ventilator cart together so someone can continue to breathe while the body fights off an illness, or for providing the conduction needed to keep a neural implant functioning properly to keep seizures at bay, canted coil springs are a critical component in many different medical applications. If your design needs a reliable mechanical connector, a spring-energized seal, EMI/RFI shielding, or a multiple contact point conductor, contact Advanced EMC today to learn more about the products and options available for your application.