Springs - Torsion

Part Number	Description / PDF	Quantity
TO-5238LCS Century Spring Corp.	TOR O=1.148, W=.125	414
TO-5253LSCS Century Spring Corp.	TOR O=1.465, W=.115	104
TO-5123LSCS Century Spring Corp.	TOR O=.472, W=.035	197
TO-5075RCS Century Spring Corp.	TOR O=.341, W=.025	850
TO-5187RSCS Century Spring Corp.	TOR O=.781, W=.078	239
TO-5228LCS Century Spring Corp.	TORS O=1.110, W=.095	581
TO-5111RCS Century Spring Corp.	TOR O=.436, W=.035	685
TO-5171RCS Century Spring Corp.	TOR O=.681, W=.059	364
TO-5240LCS Century Spring Corp.	TOR O=1.162, W=.135	244
TO-5077LCS Century Spring Corp.	TOR O=.353, W=.038	454
TO-1129CS Century Spring Corp.	TOR O=.658, W=.063	118
TO-5175LCS Century Spring Corp.	TOR O=.699, W=.059	897
TO-5147RCS Century Spring Corp.	TORS O=.564, W=.055	1109
TO-5057RSCS Century Spring Corp.	TOR O=.271, W=.023	462
TO-5199RSCS Century Spring Corp.	TOR O=.871, W=.063	302
TO-5186LCS Century Spring Corp.	TOR O=.767, W=.063	95
TO-5103RSCS Century Spring Corp.	TOR O=.386, W=.038	117
TO-5166RCS Century Spring Corp.	TOR O=639, W=.070	250
TO-5031LSCS Century Spring Corp.	TOR O=.200, W=.021	816
TO-5049RSCS Century Spring Corp.	TOR O=.251, W=.023	358

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.