GB2203653A - A racket with improved throat portion - Google Patents

Description

2 2 0 A RACKET WITH IMPROVED THROAT PORTION The present invention relates

to a racket with an improved throat portion.

At present, rackets available on the market have a uniform cross section, which is chosen to emphasise a particular feature of the racket. For instance, some rackets put emphasis on stiffness of 'frame but neglect flexibility for an appropriate degree of bending to give proper whiplash energy, i.e., impact energy to hit a ball. On the other hand, some rackets have large flexibility and insufficient stiffness, so that the oscillation half-cycle of the hitting surface is greater than the time of contact between ball and hitting surface, and thus the outgoing ball is not hit with sufficient energy because the hitting surface does not restore its balanced position in good time. Hence the known structure is not ideal for game playing, and hitherto there has not been any satisfactory solution for the above problems.

An embodiment of the present invention provides a racket with improved throat portion for optimum stiffness and flexibility so that the oscillation half-cycle from hitting the ball is almost equal to the time of contact between the ball and hitting surface. In other words, the hitting surface can restore its ballanced position at the instant while the ball is in contact therewith, and about to leave the hitting surface. Thus, nergy of hitting can be entirely transmitted to the ball, and the outgoing ball will then fly at the highest possible speed.

A racket according to an aspect of the present invention has an improved throat portion and comprises a head portion with an open end, a throat portion extending from the open end of the head portion, and a handle extending from the end of the throat portion, and is characterised by a plurality of symmetrical and equidistant recesses on each of the upper and lower 1 surface of the throat portion parallel to the hitting surface to form an oscillation zone for optimum flexibility and appropriate stiffness.

For a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the-accompanying drawings, in which:- Figure 1 is a perspective view of a preferred embodiment according to the present invention; Figure 2 is a side view of the preferred embodiment in Figure 1; and Figure 3 compares the bending degree of the racket of Figure 1 with a racket with uniform cross section when they hit the ball.

Referring now to Figures 1 and 2, a racket 10 with an improved throat portion comprises an integral tubular structure made of fibre reinforced plastic comprising a grip 11, a handle 12 extending from the upper end of the grip 11, a pair of struts 12a and 12b extending in two opposite directions in a bifurcated manner, a pair of throat portions 13a and 13b 'respectively at the upper ends of the struts 12a or 12b, a jaw portion 14 between the throat portions 13a and 13b, and a head portion 15 in the form of a ring connected to the throat portions 13a and 13b.

The racket has, on each strut 12a, 12b, five recesses 19 each with a width of 12mm and a depth of 3.lmm arranged at 12Amm intervals on each of the upper and lower surfaces 17a, 17b, 18a and 18b parallel to the hitting plane of the racket. The recesses are located between a point A, the intersection of the head portion and each throat portion 13a or 13b, and the point B, the intersection of each strut 12a or 12b and each throat portion 13a or 13b. of course, the depth, width and distance of such recesses 19 may be varied depending on stiffness and flexibility required.

Referring to Figure 3, when the racket 10 is 1 a ball, each A-B section where the recesses 19 are located is just like an oscillation zone, and the racket 10 will bend for a degree 0 1 which is greater than 0 2' the bending degree of a racket with a uniform section (the bending degrees are shown by dashed lines in the drawing). in other words, a racket with a frame as thick as the present invention but without the recesses 19 to form oscillation zones has good strength but is less flexible than the present invention. Further, a racket with a frame thickness smaller than the thickness between upper and lower recesses 19 of the present invention does not have enough strength but has flexibility greater than that actually required.

The inventor has compared the illustrated embodiment with a wooden racket (hereinafter referred to as "Racket B"), an aluminium racket (hereinafter referred to as "Racket C), and a racket with a frame thickness equal to the present invention but without the oscillation zone A-B (hereinafter referred to as "Racket An) by a static stiffness test. In such tests the respective rackets are clamped at 6 inches (15.24cm) from the lower end of its grip, and a load to 3 kilograms is applied to the top of each racket. Degree of bending was measured and data obtained therefrom are as follows:

RACKET DEGREE OF BENDING (unit: inch) The present invention 0.165 Racket A 0.085 Racket B 0.324 Racket C 0.339 The above data demonstrated that the racket A can be deemed as one without flexibility, use of which may injure a player's arm during play, and the impulse of the outgoing ball from which is 'not strong enough. The rackets B and C are too flexible; it is hard to get any extra impulse for hitting the ball, and they are hence not ideal rackets. The racket according to the present invention has a degree of flexibility between the above two, can get a good control of the ball, and can apply large hitting impulse.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structure.

In particular the invention provides a racket with improved throat portion comnprising a head portion with an open end, a throat portion extending from the open end of the head portion, and a handle extending from the end of the throat portion, characterised by that a plurality of symmetrically and equidistant located recesses on each of the upper and lower surfaces of the throat portion parallel to the hitting surface of the racket form an oscillation zone for the optimum stiffness.

Claims (5)

CLAIMS:

1. A racket comprising a head portion connected to a handle portion by a region defining a throat portion, the -5 throat portion having on each of its upper and lower surfaces, which extend substantially parallel to a hitting surface of the head portion, a plurality of recesses.

2. A racket as claimed in claim 1 in which the throat portion comprises first and second struts extending outwardly from the handle portion to respective sides of the head portion, each strut having a plurality of said recesses.

3. A racket as claimed in claim 1 or 2, in which the recesses have the same dimensions and are equidistant one from the other.

4. A racket as claimed in claims 2 and 3, in which the recesses are symmetrically disposed on the struts.

5. A racket substantially as hereinbefore described with reference to, or as shown in, the accompanying drawings.

Publibhed 1988 at The Patent ofnee, State House, 88171 High Holborn, London WC1R 4TP. Further copies may be obtained from The Patent OffIce, Sales Branch, St Mary Cray, Orpington, Kent BRS 3RD. Printed by Multiplex techniques ltd, St Maxy Cray, Xent. Con. 1/87.