PCT No. PCT / JP97 / 00172 Sec. 371 Date Jul. 27, 1998 Sec. 102(e) Date Jul. 27, 1998 PCT Filed Jan. 27, 1997 PCT Pub. No. WO97 / 26810 PCT Pub. Date Jul. 31, 1997A back and
waist support device mounted on a seating furniture equipment such as, for example, a chair or a legless chair is disclosed. The device includes a first arm for supporting a longitudinally extending first projection arranged for forcedly pressing the back of a user and a second arm for supporting a longitudinally extending second projection arranged for forcedly pressing his
waist, as well as springs arranged on the first arm and second arm so as to urge the first projection and second projection in a direction of forcedly pressing the back and
waist, respectively, resulting in being constructed in a manner to be pivotally movable. The first and second arms per se each may be constructed into an elastic structure, to thereby eliminate arrangement of the springs. Also, an angle between the first arm and the second arm may be adjustable. Such construction permits the first projection and second projection to effectively forcedly press the back of a user and his waist irrespective of a posture of the user such as, for example, his sitting with a slouch, his sitting forward on a seat or the like, so that the user may throw out his chest and stretch his backbone while relaxing his body, resulting in relieving his fatigue.