Distance measurement device between headrest and head, distance measurement method between headrest and head, headrest position adjustment device, and headrest position adjustment method

摘要

A headrest position adjusting device 100 includes a distance measuring device 10 and a drive motor unit 30. The distance measuring device 10 includes a plurality of sensing electrodes 11 to 15 and a detecting circuit 20. The detecting circuit 20 includes a plurality of capacitance sensing circuits 21 to 25 connected one-to-one to the sensing electrodes 11 to 15, and an arithmetic processing circuit 28. The drive motor unit 30 includes a motor driving circuit and a drive motor. Based on the detected capacitance values, the detecting circuit 20 calculates a difference value between a capacitance value of the sensing electrode which shows the largest capacitance value and the capacitance value of the sensing electrode which shows the lowest capacitance value, and thereby measures an electrode-head distance L. A position adjusting operation for a headrest 43 is performed based on the measurement result.