Constant Force Spring
Constant Force Spring is a specially designed spring that delivers near-constant output force during extension or retraction, unlike the variable force characteristics of traditional springs. Below is a comprehensive analysis of constant force springs:
- Core Principle & Structure
- Unique Design:
Consists of a pre-stressed spiral steel strip (typically high-carbon stainless steel) tightly wound into a coil. When extended, the strip unwinds from the spool and recoils when retracted.
- Constant Force Mechanism:
The change in bending radius cancels out the material’s elasticity, maintaining stable force output throughout (Hooke’s Law does not apply).
- Application:
✦ Electric Fan Industrial Use:
✦ Automatic cable/hose retractors (e.g., CNC machine cable management)
✦ Constant-pressure control in safety valvesOffice Equipment:
✦ Printer paper auto-rewind mechanisms
✦ Monitor screen（lift systems)- Medical Devices:
✦ Electric hospital bed height adjustment
✦ Force feedback systems in surgical instruments - Automotive Industry:
✦ Seatbelt pretensioners
✦ Anti-pinch mechanisms for power windows - Shuangyuan produce this kind of spring with thickness 0.2mm~0.4mm, width 10mm~30mm, length according to customer requirements.
- Various kind of ends for your to choose.
- Medical Devices:
