Double Cone Springs

Definition: Double cone springs are open wound coil springs with variable diameters. They also known as barrel or barbell springs. They are coil springs with tapered ends forming a concave or convex shape thus simulating that the spring is made of two cone springs.

barrel and barbell springs

Double cone springs are also known as barrel or barbell springs. They are used for the same reason you use a conical spring; to provide stability and/or reduce solid height. In the case of these barrel or barbell springs, they will give your long compression spring the stability it needs and give you a bit more space as opposed to a conical spring that’ll need a larger outer diameter on the base and a smaller outer diameter at the top thus making the end with the larger outer diameter much weaker meaning that’s the part that’ll start deflecting first.

barrel spring deflection

The deflection in a barrel or barbell spring works the same way. The side with the largest outer diameter will compress faster. In the case of a barrel spring, they have a convex shape so the large outer diameter is in the middle while the smaller outer diameters are at the ends. This means that the barrel spring will begin compressing from its center first.

In the case of a barbell spring which has a concave shape, the ends measure the large outer diameters while the center of the spring will have the small outer diameter. These start compressing from the ends equally as if being pushed into the center.

double cone spring equals barrel spring

double cone spring equals barbell spring