GB2262046A

GB2262046A - Games racket

Info

Publication number: GB2262046A
Application number: GB9223042A
Authority: GB
Inventors: Robert Christopher Haines
Original assignee: Dunlop Ltd
Current assignee: Dunlop Ltd
Priority date: 1991-11-12
Filing date: 1992-11-04
Publication date: 1993-06-09
Also published as: GB9223042D0

Abstract

A games racket particularly for tennis has a stringing system in which separate holes are used for main- and cross- strings and the holes alternate between notional parallel planes 1, 2 each side of the plane 3 of interlaced main- and cross- strings and equidistant therefrom. In the regions of proximity of main- and cross-strings the holes P1, P2, Q1, Q2, W1, W2, X1, X2 for adjacent non-interlacing strings are aligned in a plane perpendicular both to the plane of interlaced main- and cross- strings and to the tangent to the head frame portion at this point. <IMAGE>

Description

GAMES RACKET The present invention relates to a games racket for example for tennis, squash or badminton. The improvement resides in a novel stringing system which gives beneficial playing effects to the resulting racket.

Most games rackets comprise a head frame portion and a handle portion, the head frame portion being provided with holes extending therethrough and two sets of strings one substantially longitudinal (the "main" strings) and one substantially lateral (the "cross" strings), the main strings and the cross-strings interlacing with each other to provide substantially planar playing surfaces. The strings constituting the "mains and "crosses" may or may not cross at right angles. As the head frame portion is strung by passing strings through the holes to a great extent the configuration of the strings will of course be determined by the configuration of these holes. Most rackets are made so that the axis of each hole lies within a central plane defined by the interlaced mainand cross- strings, termed 'the plane of interlaced strings'.

We have found an advantageous effect where the holes for the strings are arranged to lie other than in the plane of interlaced strings and the holes corresponding to the adjacent ends of main- and cross-strings are positioned in a particular way.

According to the present invention, a games racket comprises a head frame portion defining a substantially planar assembly of interlaced main- and cross-strings which pass through individual holes in the head frame portion which are axially positioned in one of two notional planes parallel to the plane of interlaced main- and cross- strings and positioned one on each side and equidistant from said plane of interlaced main- and cross- strings such that successive ends of the main-strings and of the cross- strings enter holes positioned alternately in different notional planes, and at each place where the ends of main- and cross-strings are adjacent then holes for these strings are positioned in said notional planes and in a plane perpendicular both to the plane of interlaced mainand cross- strings and to the tangent to the head frame portion at this point.

Other than where the ends of the main- and cross-strings are adjacent the holes are offset in reiation to each other rather than being aligned in planes perpendicular to the plane of interlaced mainand cross-strings.

A potential playing advantage of the present invention is that for ball contact near the frame, the ball is supported primarily by half the number of strings than would normally be the case and this has the effect of lessening the shock of ball impact felt by the player. This generally improves the feel of the racket for ball contact over the whole strung playing surface.

An embodiment of the present invention will now be described by way of example only.

Figure I is a part front view of a novel games racket head; Figure II is a part side view of the novel games racket head of Figure I; and Figures III and IV are part sections through one side of the games racket head of Figure I.

Referring now to Figures I and II, the holes lie in two notional parallel planes 1, 2 one on each side of the plane of interlaced main- and cross- strings 3 parallel to and equidistant from it. Pairs of holes P1 P2 Q1 Q2r W1 W2 and X1 X2 corresponding to adjacent ends of main- and cross-strings are substantially in alignment perpendicular to the plane of interlaced strings 3 and to the tangent 4 to the head frame portion 7 at this point.

Preferably the stringing is arranged so that the ends of the main- and the ends of the cross-strings 5, 6 go to holes which alternate from one notional plane to the other (See Fig III).

It will be appreciated that as the main- and cross-strings are interlaced, the main body of strings will remain in a plane which is identical to the plane which they would occupy in a conventional racket i.e.

the plane of interlaced strings. However, near the frame individual strings will depart from this plane so that they can pass through holes arranged in the notional separate planes on each side of the plane of interlaced strings. The angle Which these individual strings make with the plane of interlaced strings will depend upon (a) The separation of the notional planes from the plane of the strings N (b) The proximity of the position where the string is interlaced with the string that crosses it at a position closest to the frame M. (See Fig. IV) The object of the invention is to maintain N constant for all holes and to keep 6 as small as possible consistent with a satisfactory spacing of the strings, both at the centre of the playing surface and near the frame of the head.

The head frame portion is strung so that opposite ends of each string are either in the same notional plane or in different notional planes. Adjacent strings will be in the opposite sense i.e. one string end goes up, next string end goes down. In a preferred embodiment the main-and cross-strings positioned in the central region of the head of the racket (i.e.

that region enclosed by the rectangle or quadrilateral inscribed within the racket head defined either by the two outermost cross-strings and the two corresponding main-strings or the two outermost main-strings and the two corresponding cross-strings) are positioned such that both ends of each string go through holes in the same notional planes. These strings constitute more than two-thirds (66.678) of the total number of strings of the racket and typically over 75%.However in an advantageous embodiment the number of strings meeting these criteria is substantially 100%, thus allowing the full area of the string surface to contribute to the playing advantage of such an arrangement which is that as the string bed (playing surface) is deformed by a ball contacting the strings, the tension in adjacent strings changes in that one increases and the other -decreases.

This has the effect of causing alternate strings with high tension to bite more deeply into the ball surface than they would otherwise do, so that increased spin can be imparted to the ball. Greater bite will also be obtained for instance for a shuttlecock cork which can be advantageous in the game of badminton. This preferred configuration may be achieved by providing an odd number of main-strings and an odd number of cross-strings.

In the positions on the head frame where the ends of pairs of main- and cross-strings are adjacent then the two holes for each pair are positioned not only in different notional planes but also in a plane perpendicular to both the plane of interlaced strings and to the tangent to the head frame portion at these positions. Depending upon the shape of the racket head portion these positions of adjacent main- and cross-strings may coincide approximately with the "corners" i.e. at the 2 o'clock, 4 o'clock, 8 o'clock and 10 o'clock positions.

Claims

CLAIMS:

1. A games racket comprises a head frame portion defining a substantially planar assembly of interlaced main- and cross-strings which pass through individual holes in the head frame portion which are axially positioned in one of two notional planes parallel to the plane of interlaced main- and cross- strings and positioned one on each side and equidistant from said plane of interlaced main- and cross- strings such that successive ends of the main-strings and of the cross-strings enter holes positioned alternately in different notional planes and at each place where the ends of the main- and cross-strings are adjacent then holes for these strings are positioned in said notional planes and in a plane perpendicular both to the plane of interlaced main- and cross- strings and to the tangent to the head frame portion at this point.

2. A games racket according to Claim 1 in which more than two-thirds of the total number of main-strings and cross-strings are arranged so that opposite ends of those strings will be in the same notional plane.

3. A games racket according to Claim 1 or 2 which has an odd number of main-strings.

4. A games racket according to Claim 1, 2 or 3 which has an odd number of cross-strings.

5. A games racket according to any preceding claim wherein there is more than one pair of adjacent ends of main- and cross-strings.

6. A games racket according to any preceding claim and substantially as described with reference to any one of Figures I to IV.

7. A games racket according to any one of claims 1 to 5 and substantially as described herein.

8. A method of stringing the head frame portion of a games racket comprises providing holes in the frame for main- and cross-strings the holes being positioned in two parallel notional planes and the strings being threaded through said holes such that successive ends of the main- and of the cross-strings enter holes positioned alternately in different notional planes, the main- and cross-strings interlacing with each other in a plane between and parallel with the notional planes and equidistant therefrom, wherein at each place where the ends of the main- and cross-strings are adjacent then holes for these strings are positioned in said notional planes and in a plane perpendicular both to the plane of interlaced mainand cross-strings and to the tangent to the head frame portion at this point.