| 摘要 |
PROBLEM TO BE SOLVED: To improve the rigidity of the back frame of a chair using a torsion bar as a rocking spring. SOLUTION: A pair of tubular members 16 are engaged in the torsion bar 21 from its outside and the right and left tubular members 16 are welded to the center braket 17. On the outer end of the tubular member 16, a rectangular cylindrical member 22 is formed in flat shape and the end of the torsion bar 21 is engaged relatively non-rotatably in the rectangular cylindrical member 22. At the end of the tubular member 16, an arm member 23 extending backward is welded. The arm member 23 and the back frame 8 are engaged in and connected with each other with a screw inserted from the lower side of the back frame 8. The torsion bar 21 is firmly held by the rectangular cylindrical member 22. The back frame 8 maintains a high rigidity, since the right and left back frames 8, tubular member 16 and center braket 17 are incorporated in a frame member. COPYRIGHT: (C)2010,JPO&INPIT |
