What is the internal winding method of the airbag clock spring?
3 Answers
Internal winding method of the airbag clock spring: Generally, it involves first turning clockwise to the end, then turning counterclockwise for 3.5 turns. Below is a related introduction to the airbag system: 1. Definition: The airbag system is a passive safety (see vehicle safety performance) protection system. When used in conjunction with seat belts, it provides effective collision protection for occupants. 2. Composition: It mainly consists of an airbag sensor, collision airbag, and electronic control device. The driver-side collision airbag is installed in the steering wheel, while the passenger-side collision airbag is usually installed on the dashboard. Airbag sensors are installed on the left, right, and center of the cabin partition; the central airbag sensor and airbag system are integrated with the electronic control device. The airbag module primarily consists of the airbag, gas generator, and igniter.
The internal winding method of the clock spring is quite fascinating. Let me use an old-fashioned tape recorder as an analogy—it contains a specially designed flat ribbon cable that spirals around a rotor core like a cassette tape. When the steering wheel turns, the ribbon cable unwinds or winds accordingly, but it must not be too loose or too tight; the unwinding angle must be precisely calculated. Engineers design it with extra loops to ensure there's always slack when the steering wheel is turned to full lock in either direction. The most critical aspect is ensuring the ribbon cable is wound in the correct layered direction, with each layer stacked in reverse, so the turns don't tangle. During installation, specialized tools must be used to locate the neutral point, ensuring the clock spring remains in a balanced tension position when the steering wheel is centered. This job may seem simple, but it actually demands extremely high precision.
I've disassembled many clock springs, and their core is essentially a long, flexible circuit board. The ribbon cable is coiled in alternating layers on the turntable bracket, switching winding direction every 90 degrees. This allows the cable to breathe and expand/contract as the steering wheel turns 2.5 rotations, preventing breakage or twisting into knots. The most skill-demanding step is final assembly: ensuring the cable slides freely inside the housing without sticking, while adding alignment marks for technician calibration. If you hear a clicking sound at full steering lock, it's likely misaligned winding layers - replace it immediately before the airbag warning light activates. Newer models now incorporate temperature-compensating materials to prevent thermal expansion issues.
