| 摘要 |
<p>1,039,105. Ball projectors. S. HJELMQUIST. May 3, 1963 [May 5, 1962], No. 17693/63. Heading A6D. A ball projector for use in training for table tennis or other ball games, comprises two endless moving belts, the speeds of which are independently variable and reversible, and which are mounted on a stand C whose orientation and inclination to the horizontal are also adjustable. Thus balls fed to the apparatus at A are projected therefrom at B with a speed, trajectory, and spin which can be varied at will.</p> |
