Football with a modified surface conferring altered aerodynamic properties

Abstract

A generally prolate-spheroidal, inflatable game ball with a plurality of air-turbulence-producing depressions distributed over a majority of the outer surface of the skin. The depressions produce a preferably circular surface shape, with a breadth of less than about one-quarter inch and preferably having a breadth to depth ratio of about 2 to about 6. The game ball of the present invention is preferably an American-style football, wherein the depressions are distributed substantially uniformly over the majority of the outer surface. A method for providing the game ball with altered aerodynamic performance may include forming depressions by embossing the skin or molding depressions therein.

Description

FIELD OF THE INVENTION [0001] This invention relates to game balls having a generally prolate-spheroidal shape, particularly American-style footballs, and to altering the aerodynamic behavior of the balls by providing air-turbulence-generating depressions in the surface thereof. BACKGROUND OF THE INVENTION [0002] In sports involving throwing, hitting, kicking or otherwise impelling a game ball, the performance characteristics of the ball can greatly affect the play of the game. Properties of the ball such as the inflation pressure, rigidity, and surface characteristics all influence the speed with which the ball can be projected and the attributes of its flight. Although the size, shape and weight of a particular kind of ball are typically governed by the traditions and rules of the given game, it is possible to modify or improve the performance properties of a ball through altering its surface properties. For instance, tennis balls with differing surface properties of their felt co...

AI Technical Summary

Benefits of technology

[0010] The present invention provides a generally prolate-spheroidal game ball with a plurality of air-turbulence-producing depressions distributed over a majority of the outer surface of the skin. The depressions are preferably circular in shape, with a breadth of less than about one-quarter inch and preferably having a breadth to depth ratio equaling about 2 to about 6, and a surface density of about 23 to about 27 depressions per square inch. The game ball of the present invention is preferably an American-style football, substantially covered by a regular array of the depressions. When the football translates through the air, particularly when the football is thrown in a spiral pass wherein it rotates only around its longitudinal axis while translating through the air, air turbulence induced by the depressions alters the aerodynamic properties of the football. The depressions reduce separation of the flow of air by the translating ball and thus reduce air resistance, resulting in a longer flight for a given initial impetus. The depressions also reduce air resistance to the spinning motion, thus allowing for a more prolonged spin and a decreased rate of loss of rotational velocity for a given initial rotational impetus, which results in improved, longer-lasting gyroscopic stabilization of the flight.

Problems solved by technology

When the football translates through the air, particularly when the football is thrown in a spiral pass wherein it rotates only around its longitudinal axis while translating through the air, air turbulence induced by the depressions alters the aerodynamic properties of the football.

The depressions reduce separation of the flow of air by the translating ball and thus reduce air resistance, resulting in a longer flight for a given initial impetus.

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