| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a light-weight and inexpensive throttle body by solving the problem of inconveniences caused by anisotropy when a resin material is thermally expanded or contracted. SOLUTION: A level difference part 11 composed of a projecting step part 11a is formed in the outer peripheral wall of a throttle body 10 surrounding a throttle valve. The throttle body 10 is made of a resin material and a glass fiber or a carbon fiber is contained in the resin material for increasing strength. A recessed part is formed in a molding type position corresponding to the step part 11a and, when passing through this recessed part, the flow of the resin material is disturbed and the orientation of the fiber material mixed therein is randomly disturbed. The random disturbance of the orientation of the fiber material is unitedly produced on the circumference of the throttle body 10 having the level difference part 11. Thus, since the throttle body 10 shows isotropy when being thermally expanded or contracted, variance in clearance formed by the outer peripheral edge of the throttle valve and the inner wall of the throttle body 10 is prevented.</p> |
