| 摘要 |
PROBLEM TO BE SOLVED: To provide a thermalplastic resin-made flapper which has excellent accuracy of dimensions, excels in productivity, is lightweight and excels in a recycling property by integrally molding a shaft part and a claw part by using a thermalplastic resin and forming a hollow part in the inner part thereof. SOLUTION: This flapper used for OA equipment or the like comprises a shaft part 5 and a plurality of claw parts 7 provided along in the direction of the length of the shaft part 5, which are integrally molded with the shaft part by using a thermalplastic resin, and a hollow part 8 is formed in the inner part thereof. At that time, the hollow part 8 is formed so as to satisfy a relationship defined by a formula: 0.9<=L(b/L (a)<=1, where L(a) designates the total length along the axial line of the flapper and L(b) designates the length of the hollow part along the axial line of the flapper. Also, it is formed so as to satisfy a relationship defined by a formula: 10<=Vh<=50, where Vh designates a hollow percentage % of the flapper. For a thermalplastic resin used for such a flapper, a polyacetal resin, a polyamide resin or the like is used. |
