| 摘要 |
PURPOSE:To increase the protection effect of the U turn part of a gut folded and extended to respective gut holes of a frame string stretching part by directing a tongue piece to close the releasing part of a concave groove respectively to the inside, mutually facing it and bending and forming it at the tip of respective side parts. CONSTITUTION:A concave groove 13 is formed by a bottom side base 11 to straddle between respective mutually adjoining gut holes 2 and 2 of a frame string stretching part 1 and a pair of side parts 12 and 12 to extend and open from both sides to the outside of the said bottom side base 11. At a frame groove 3 of the frame string stretching part 1, a fittable cross section shape is held in a closely contact condition, and at the tip of respective side parts 12 and 12, tongue pieces 12a and 12a are bent and formed to the chevron shaped cross section at the inside so as to face mutually. Thus, since the releasing part of a concave groove is closed, a gut U turn part folded and stretched to the outer peripheral side surface of the frame string stretching part is closed and held in the concave groove of the gut protecting belt and the invasion of a small stone, etc., into the concave groove and the exposure to the external part of the gut U turn part are prevented. |
