| 摘要 |
<p>PROBLEM TO BE SOLVED: To decrease the load acting columns of a supporting case, inner rim, inner rails, etc., by mounting reinforcing members for supporting the load acting on a frame body by spreading of strings at the frame body, thereby increasing the rigidity of the frame. SOLUTION: The side end 1c of the frame 1 is provided with the reinforcing member 20 in the lower part of the bone part 100 of the frame 1. This reinforcing member 20 is disposed also at the base of the bone part existing at the other side end of the frame 1. The reinforcing member 20 is composed of two pieces of brackets 21, 22 and the backpost 23. The bracket 21 is fixed by means of screws 24 to the base 100a of the bone part 100. The light and highly rigid reinforcing members 20 are disposed at the bases of both side ends of the frame 1, by which the reinforcing members 20 support bending compressing load cooperatively with the brackets 21, 22 and the backposts 23 when the tension of the many strings act to deflect both ends 1a, 1b of the frame 1 downward, i.e., the bending compressive load acts on the base side of the frame 1.</p> |
