| 摘要 |
PURPOSE:To instantaneously detect external forces caused by collision from any direction and surely actuate a safety device in the case of a collision by extending a collision-detecting optical fiber cable around roughly the whole periphery of a vehicle. CONSTITUTION:In the normal running state of a vehicle, light incident from a light-emitting element portion 5 is transmitted through an optical fiber cable 4 while total reflection at the boundary face between a core portion 9 and a clad portion 10 is repeated, and most part of the light impinges on an optical transfer element portion 6 and so the quantity of the light is not varied, and a collision detection circuit 8 does not actuate a safety device 2 for an air bag or the like but simply monitors the quantity of the light. If collision occurs and its external force is applied to either one of collision detection sensors 7, however, the optical fiber cable 4 is partially curved and deformed and conditions for total reflection are lost and the quantity of the light being transmitted is excessively reduced; the optical transfer element portion 6 detects it and then inputs a signal indicating it to the collision detection circuit 8, thereby actuating the safety device 2. |
