Patent ID: 8690252

Claim:
A headrest position adjusting device, comprising: a plurality of sensing electrodes which are provided in a headrest provided on a seat of a vehicle for sensing capacitances between a head of a human body sitting on the seat and the headrest, the sensing electrodes being provided side by side along a height direction of the headrest; a detecting circuit which detects a height position of the head based on sensing signals from the plurality of sensing electrodes; and position adjusting means which adjusts a position of the headrest with respect to the head based on the height position of the head in accordance with a detection result from the detecting circuit; wherein the detecting circuit determines whether a distance between the headrest and the head is equal to or shorter than a predetermined threshold distance, and wherein the position adjusting means adjusts the position of the headrest when the distance between the headrest and the head is determined equal to or shorter than the predetermined threshold distance, and stops the headrest or moves the headrest to a predetermined position when the distance between the headrest and the head is determined longer than the predetermined threshold distance.