| 摘要 |
<p>A tennis racket frame 12 comprises at least one conduit means containing a fluid. The fluid may be viscoelastic, and is preferably a dilatant fluid which hardens under impact. The frame preferably comprises first and second conduit means 30a, 30b located within or along opposing portions AA-BB and A'A'-B'B' of frame 12 in a direction generally parallel to a longitudinal axis of the racket. The conduit means 30a, 30b may each comprise a pair of tubings, one tubing of each pair being located on opposing sides of a plane defined by the racket strings (not shown). The conduit means is preferably located within the frame. Alternatively, the conduit means may comprise a device such as a bumper (40, fig.5) attached to the racket frame, with the conduits formed at least partly of transparent material. In use, movement of fluid within the conduits allows mass to concentrate at different parts of the racket frame depending on the orientation and movement of the racket, and playing characteristics of the racket can be modified depending on the nature of the conduits and fluid used. A method of making a racket frame containing fluid-filled conduit means is also disclosed.</p> |
