John Evans’ Sons is an international leader in constant force spring design and manufacturing.
Long deflection, without significant change of force, is a key characteristic of constant force springs. As a balancing mechanism, the constant force spring is more compact and lighter than most other methods and can eliminate deadweights, linkages, cylinders, and other systems. As a return or retracting mechanism, the constant force spring will provide a smooth, even, uniform load through its entire length of travel (deflection). Constant tensioning or pressure is also a constant force spring attribute.
There are many design factors that will affect the time and cost needed to manufacture your spring. Therefore, it’s important to work with a manufacturer like John Evans’ Sons that has the knowledge needed in the design phase.
Our strongest selling points are our custom design capabilities, in-house tooling services, precision manufacturing, a wide and varied stock spring selection, and our commitment to quality and on-time delivery.
To help you in the product selection process, this page will discuss the design considerations of constant force springs, which include: