Where it earns its place
Best-Fit Uses
One-sided lever and latch return
Uses one active arm to bring a moving part back while the other end is anchored close to the coil.
Compact covers and selectors
Fits spring action around a pivot without requiring two long external legs.
Returning a lever or hinged part
Provides a turning force around a pivot so a moving arm comes back toward a preferred angle.
Helping open or close a panel
Can assist or oppose rotation when the spring is arranged around the same pivot as the moving part.
Why this style works here
What This Spring Style Solves
This arrangement can keep the spring package compact around a pivot because one end disappears into a hole, slot or other fixed feature.
Before you choose it
What to Confirm in Your Assembly
- Show exactly how the retained end is captured and how much it is allowed to move.
- Define the working-leg length, contact point, free angle and maximum working angle.
- Show the pivot or shaft diameter and the free and working leg positions.
- State the required torque at one or more angles and the direction in which the spring is loaded.
- Identify which leg or end is fixed and which one moves with the assembly.
Avoid forcing the wrong spring into the design
When Another Spring Style May Fit Better
The hidden anchored end is part of the working system. If it can rotate, dig into plastic or move in its slot, the actual angle and torque can drift away from the intended condition.
- Straight-leg torsion springs for two simple external stops
- Double-leg torsion springs for more symmetrical loading
- Hairpin springs for shallow open layouts
Keep material selection separate
Environment & Material Direction
Once the working angle, torque and fit around the pivot are known, use the Materials section to choose an alloy for corrosion, temperature or fatigue needs.
For the material families represented in this product's reference configurations, compare Carbon & Alloy Spring Steels, Stainless Steel Spring Materials, Copper Alloy Spring Materials, Nickel & High-Temperature Spring Alloys. Confirm the exact grade and condition for your assembly.
Move from the use case to the specification
Where to Go Next
Related Spring Design Guides
Review the dimensions, working loads and drawing requirements for this spring family.
Engineering Guides for This Product
These guides contain material, wire-diameter or standard data related to this product.
Application questions
Frequently Asked Questions
How should the fixed end of a single-leg torsion spring be retained?
It should sit in a feature that prevents unwanted rotation without sharply bending or crushing the wire. Show the retention detail on the assembly drawing rather than treating it as a generic anchor.
Why does winding direction matter?
A torsion spring is normally intended to tighten around its axis as it is loaded. Reversing that direction can open the coil, change the fit around the shaft and produce a different stress condition.
What should I send for an application review?
Send the assembly drawing or a clear sketch, the working positions, the force or torque you need, expected cycles, environment and quantity. If an existing spring is being replaced, include its dimensions and explain what is not working well in the current design.
Same application family