| 摘要 |
PURPOSE: Provided is a soft tennis ball which is light and constituted of a single body, and is equipped with a rubber valve by which air in the ball does not leak out to the outside, and a sealing effect is sufficiently obtained. CONSTITUTION: The soft tennis ball includes a rubber valve(3) for air injection. The rubber valve is bonded to a part in the ball spherical shell(2). The rubber valve has a thinner flange part(3b), a protruding part which protrudes to the outside from the flange part, an opening having a bottom, a pillar-form valve body(3c) which extends inward from the flange part, and a slit(3e). The flange part is bonded to the inner peripheral surface of the ball spherical shell. The protruding part engages with a small hole of the ball spherical shell. The bottom is provided on the external surface of the protruding part. The opening is formed in the rubber valve. The valve body is formed into a tapered shape wherein the outer diameter is gradually reduced toward the inside from the outside.
|
