| 摘要 |
<p>The ball for use in a variety of sports has an outer skin consisting of pieces of a strong material. It is made from leather, synthetic or plastics material. The pieces are sewn together using a thread, which consists of interwoven, plaited, knitted etc. fibres (17, 18, 19). The thread is hollow, the individual fibres forming a tube, and the central portion of the tube is empty. The pieces of material forming the skin of the ball consist of alternate pentagons and hexagons, which form an approx. spherical body when their edges are sewn together.</p> |
