PURPOSE: To enhance an effect for stretching a backbone line by making the projection amount of a therapeutic element different between ascending mode and descending mode on the basis of the detected value of the amount, regarding a kneader where the therapeutic element built into the back of a chair or the like is freely rotated and moved vertically for stretching the backbone line.
CONSTITUTION: Movable sleeves 65 having respective eccentric cam sections 65a are formed at both sides of a kneading massage shaft 52. Also, an arm 68 having a freely rotatable massage roller 69 as a therapeutic element at the end is jointed to the external surface of the cam section 65a via a bearing 66. Then, the shaft 52 is half turned via a kneading power transmission system including a motor 33, thereby adjusting the projection amount of the element 69 toward the front of the back of a chair, depending upon the eccentric amount of the section 65a. Furthermore, the projection amount of the element 69 is enlarged to provide a backbone line stretching effect, depending upon the projection amount of the element 69 detected with a projection amount sensor. At the same time, the projection force of the element 69 is reduced, when the element 69 reversibly descends.
HOSHINO SHOJI
MOCHIDA MIKIO
