Springs - Torsion

Part Number	Description / PDF	Quantity
TO-5178RCS Century Spring Corp.	TOR O=.748, W=.085	31
TO-5051LSCS Century Spring Corp.	TOR O=.259, W=.017	214
TO-5172RCS Century Spring Corp.	TOR O=.685, W=.075	457
TO-5126LCS Century Spring Corp.	TOR O=.484, W=.054	132
TO-5228RCS Century Spring Corp.	TORS O=1.110, W=.095	666
TO-1068CS Century Spring Corp.	TOR O=.302, W=.034	1759
TO-1016CS Century Spring Corp.	TOR O=.612, W=.040	1384
TO-5068RCS Century Spring Corp.	TOR O=.305, W=.030	668
TO-5155RCS Century Spring Corp.	TOR O=.575, W=.063	220
TO-5164LSCS Century Spring Corp.	TOR O=.628, W=.051	317
TO-5124LCS Century Spring Corp.	TOR O=.474, W=.045	123
TO-1109CS Century Spring Corp.	TOR O=.544, W=.068	387
TO-5125RCS Century Spring Corp.	TOR O=.477, W=.038	483
TO-5245RCS Century Spring Corp.	TOR O=1.243, W=.095	1267
TO-5082RCS Century Spring Corp.	TOR O=.359, W=.040	656
TO-5211LCS Century Spring Corp.	TOR O=.944, W=.096	124
TO-5070RCS Century Spring Corp.	TOR O=.316, W=.035	3526
TO-5031RCS Century Spring Corp.	TOR O=.200, W=.021	1107
TO-1018CS Century Spring Corp.	TOR O=.971, W=.064	140
TO-5165LCS Century Spring Corp.	TOR O=.637, W=.075	152

Springs - Torsion

1. Overview

Torsion springs are elastic components designed to store and release angular energy or to statically hold a mechanism in a rotated position. They operate by twisting about their axis when torque is applied, generating a restoring force proportional to the rotation angle. These springs are critical in modern mechanical systems for precise motion control, vibration damping, and maintaining structural stability across industries.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Single Torque Torsion Spring	Simple helical design with one direction of torque output	Door hinges, clipboards, automotive latch mechanisms
Double Torque Torsion Spring	Bifilar winding for balanced torque in two directions	Counterbalance systems, robotic joints
Multi-Flex Torsion Spring	Segmented coils for variable torque curves	Industrial valves, precision instruments
Linear Torsion Spring	Constant torque output through entire rotation	Cable reels, rotational actuators
Tapered Torsion Spring	Variable pitch coils for progressive torque response	Aerospace control surfaces, clutch mechanisms

3. Structure and Composition

Typical torsion springs feature helically wound wire with straight or shaped ends (legs) that transmit torque. Key components include:

Coiled body: Provides elastic deformation through torsional stress
Arms/legs: Transfer torque to mating components (straight, angular, or hooked configurations)
Material: High-carbon steel, stainless steel, phosphor bronze, or titanium alloys
Surface treatment: Zinc plating, powder coating, or nitriding for corrosion resistance

Design variations include cylindrical, conical, and barrel-shaped geometries to optimize space utilization.

4. Key Technical Parameters

Parameter	Description	Importance
Spring Rate (Nm/deg)	Torque per degree of angular deflection	Determines stiffness and response characteristics
Max Torque Capacity	Ultimate torsional load before plastic deformation	Defines operational safety limits
Number of Coils	Impacts spring index and stress distribution	Affects fatigue life and space requirements
Leg Orientation	Angle and offset between spring arms	Critical for proper torque transmission
Material Shear Modulus	Dictates elastic properties under torsion	Key factor in torque-rotation relationship
Operating Temperature Range	Thermal limits affecting dimensional stability	Determines environmental compatibility

5. Application Fields

Major industries utilizing torsion springs include:

Automotive: Windshield wiper mechanisms, door check systems, transmission shifters
Industrial Equipment: Conveyors, packaging machines, robotic arms
Aerospace: Flight control actuators, landing gear mechanisms
Consumer Electronics: Laptop hinges, camera lens barrels, medical device triggers
Energy Systems: Circuit breaker mechanisms, renewable energy dampers

Example: Automotive seat recline systems use dual torsion springs to maintain position while allowing smooth adjustment.

6. Leading Manufacturers and Products

Manufacturer	Key Products	Specialization
MISUMI	VFS2- Series Precision Torsion Springs	High-volume industrial applications
Lee Spring	CT Series Custom Torsion Springs	Miniature and medical-grade springs
Barnes Group Inc.	Associated Spring RAFI Line	Aerospace and defense solutions
Smalley Steel Ring	Wave Spring-Actuated Torsion Devices	Space-saving wave spring technology
Crosby	Swager Torsion Springs	Heavy-duty industrial applications

7. Selection Guidelines

Key considerations for torsion spring selection:

Calculate required torque using: M = k (M=torque, k=spring rate, =angular displacement)
Verify maximum stress levels against material endurance limits
Account for installation space constraints (diameter, length, leg clearance)
Specify corrosion resistance requirements based on environmental exposure
Consider dynamic loading conditions and fatigue life expectations
Validate rotational direction compatibility with handedness of coil winding

Recommend consulting manufacturer's load-deflection charts during specification.

8. Industry Trends

Current development trends include:

Advanced materials: Carbon fiber composites and shape-memory alloys
Miniaturization for micro-electromechanical systems (MEMS)
Smart integration with embedded strain sensors
Topology optimization via generative design algorithms
Environmentally friendly surface treatments replacing hexavalent chromium

Market growth driven by electric vehicle component demands and industrial automation expansion.