INFLATABLE BALL FOR BALL GAMES, IN PARTICULAR FOOTBALL.

摘要

An inflatable ball for ball games comprises an outer ball having interconnected parts consisting of twelve equilateral pentagons (1) and twenty equiangular hexagons (2). Each pentagon (1) is enclosed by five hexagons (2) and at the location of the connection between a pentagon (1) and a hexagon (2) the sides connected to one another are of equal length. In order to minimise, and preferably reduce to zero, the difference in stress in the material of the hexagons (2) and pentagons (1) when the ball is in the inflated state, each of the hexagons (2) has three sides (a) of relatively great length connected to a pentagon (1), and three sides (b) of relatively small length connected to a hexagon (2), the length of the short sides (b) being at least 0.69 times the length of the long sides (a), preferably, b = 0.839 a.