DEVICE FOR MEASURING DISTANCE BETWEEN HEADREST AND HEAD, METHOD FOR MEASURING DISTANCE BETWEEN HEADREST AND HEAD, HEADREST POSITION ADJUSTING DEVICE, AND HEADREST POSITION ADJUSTING METHOD

摘要

A headrest position adjusting device (100) comprises a distance measuring device (10) and a drive motor unit (30). The distance measuring device (10) includes a plurality of detection electrodes (11 to 15) and a detection circuit (20). The detection circuit (20) includes a plurality of capacitance detection circuits (21 to 25) connected to the respective detection electrodes (11 to 15) in a one-to-one relationship and an arithmetic processing circuit (28). The drive motor unit (30) includes a motor drive circuit and a drive motor. The detection circuit (20) calculates, based on the detected capacitance values, the difference between the capacitance of the detection electrode exhibiting the highest capacitance value and the capacitance of the detection electrode exhibiting the lowest capacitance value, and thereby measures the electrode-head distance (L). An operation for adjusting the position of a headrest (43) is performed on the basis of the measurement result.