Patent ID: 7717217
Filing Date: 2010-05-18
Classification: B60R

Abstract:
1. A displacement information deriving device comprising: a metallic object to be detected which is structured as a vehicle component; a coil arranged to face the object to be detected; a coil sensor which applies an AC magnetic field to the object to be detected when the coil is energized with alternative current and which detects impedance through the coil when energized; and a deriving unit for deriving information about displacement of the object to be detected based on variations in impedance detected when the object to be detected is displaced toward the coil sensor in the event of a vehicle collision, wherein the object to be detected is displaced toward the coil sensor according to the displacement of the vehicle component by the vehicle collision and the object to be detected has an extending surface arranged to face the sensor surface of the coil sensor, and wherein the object to be detected is fixed to the coil sensor via an elastically deformable elastic body between the vehicle component and the coil sensor, and the object to be detected is pressed by the vehicle component according to the displacement of the vehicle component toward the coil sensor to move closer to the coil against the elastic force of the elastic body during the vehicle collision.