| 摘要 |
<p>A structure of a chair backrest that can be used with a back board set at a preferred angle of bend. The structure comprises a back support member (61) having a first back frame (1) tiltably attached to a seat-receiving member (8) and a second back frame (5) tiltably attached to the first back frame (1), and comprises a back board (2) having a back board-bending region (2e), a back board upper portion (2a) positioned more upward than the back board-bending region (2e), and a back board lower portion (2b) positioned more downward than the back board-bending region (2e). The back board lower portion (2b) is fixed to the first back frame (1), and the back board upper portion (2a) is supported by the second back frame (5). The back board (2) is bendable forward by deforming the back board-bending region (2e). A bending angle-adjusting mechanism (3) is provided in the structure, and the mechanism makes it possible that an angle of bend of the back board is varied and fixed by adjusting the tilt angle of the second back frame (5) with respect to the first back frame (1).</p> |
