GB2396563A

GB2396563A - Cricket bat handle

Info

Publication number: GB2396563A
Application number: GB0230141A
Authority: GB
Inventors: Tom Larsen
Original assignee: Wavex Corp Canada
Current assignee: Wavex Corp Canada
Priority date: 2002-12-24
Filing date: 2002-12-24
Publication date: 2004-06-30
Anticipated expiration: 2022-12-24
Also published as: GB0230141D0; GB2396563B

Abstract

A handle 2 for a cricket bat comprises a substantially cylindrical core having a splice end adapted to be joined to a blade to thereby form a cricket bat. The handle is provided with a jacket or surface layer 12, which is provided with a plurality of sinusoidal undulations 13 arranged on its outer surface, which undulations are adapted, in use, to dampen vibrations caused by a ball hitting the cricket bat.

Description

Cricket Bat & Handle 2396563 The invention relates to a cricket bat and in

particular a handle for a cricket bat.

Cricket is a traditional game and the basic design of a cricket bat remains the same as it was in the nineteenth century. The bat comprises a blade and a handle joined to the blade via a splice. The laws of cricket mandate that the blade is made of wood, invariably willow, but there are no laws relating to the material of the handle. The traditional handle is made of strips of cane interleaved with strips of an elastomeric material such as rubber, the whole being bound by twine wound around the handle portion. One or more rubbers are placed over the handle to improve the adhesion of the bat to a batsman's gloves and soften the feel.

In general, few attempts have been made to improve cricket bats outside the traditional design and these have tended to concentrate on the design of the blade with the aim of increasing the size of "the middle" of the bat without increasing weight. Due to the way cricket is played the weight of a cricket bat has remained fairly constant over the years, but there is a general tendency towards heavier bats as these tend to enable the ball to be hit further if the batsman has sufficient strength to manoeuvre the bat.

Other sports such as tennis, which traditionally used a similar racquet handle construction to that of a cricket bat have in recent years amended their laws to allow for the use of other materials such as carbon fibre or titanium. One major factor as to why the basic bat design in cricket has not changed is due to its dimensions, weight and the speed at which it should be used. A cricket bat is considerably heavier than other equivalent sporting goods such as a baseball bat, tennis racquet or golf club and will typically weight between 1 and 1.5kg in contrast to a tennis racquet, which weighs about 300g. The prime considerations when selecting a cricket bat is what is known as pick up and balance, which are essentially functions of weight distribution of the bat. If a bat deviates substantially from the traditional weight distribution, then it will be difficult for a batsman to use, as his shot making will be habituated to the conventional feel. Since the materials of the bat are natural, their qualities such as weight, stiffness, resilience etc., will vary due to the natural variations in the materials. This affects the characteristics of the bat so that

even bats which look identical and are made identically will have different characteristics of pick up and balance. Thus it is impossible to mass produce bats having a uniform performance and feel, which makes bat selection a difficult art.

The feel of the cricket ball hitting the bat is also important to a batsman. A cricket ball, which is made of a cork and twine core covered in leather, is also significantly heavier than a golf or tennis ball. These differences in weight and materials mean that in physical terms, the type, frequency and duration of vibrations and other forces transmitted to the batsman in use are not encountered in other sports and so many of the developments in other sports such as the adoption of aluminium bats in baseball are simply not applicable in cricket.

However, a conventional cricket bat suffers from the problem that, in use, when a ball strikes the bat in the region of the splice, not only is it difficult to impart any momentum to the ball but also significant vibrations can be transmitted along the handle causing the batsman discomfort that can last several seconds. If the ball hits a batsman's bat repeatedly in the area of the splice, particularly at speed, then this can often lead to the batsman losing his touch or concentration and being dismissed.

The present invention seeks to provide a cricket bat and a handle for a cricket bat with reduced vibration transmission to and through the handle.

According to the invention there is provided a handle for a cricket bat comprising a substantially cylindrical core having a splice end adapted to be joined to a blade to thereby form a cricket bat, wherein the handle is provided with a jacket or surface layer, which jacket or surface layer is provided with a plurality of undulations arranged on its outer surface, which undulations are adapted, in use, to dampen vibrations caused by a ball hitting the cricket bat.

In a preferred embodiment, the jacket comprises a substantially cylindrical tube.

Preferably, the undulations comprise a sinusoidal wave. Preferably, the undulations

extend around the circumference of the jacket. Preferably, the undulations extend along the entire length of the jacket.

An embodiment of the invention will now be described in greater detail with reference to the drawing in which, Fig. 1 shows a front perspective view of a cricket bat Fig. 2 shows a rear view of a cricket bat Fig. 3 shows a side view of a handle Fig. 4 shows a cross-section of the handle Figure 1 shows a cricket bat comprising a substantially rectangular, elongate blade portion 1 and a handle 2 joined to the bat by a splice 3. The blade of the bat has a rounded distal end. Law 6 of the laws of Cricket states that the bat shall not be more than 38 inches or 96.5 cm in length. The blade of the bat shall be made solely of wood and shall not exceed 41/. inches /10.8cm at the widest part.

Figure 2 shows a rear view of the cricket bat, in which the back of the blade can be seen to be generally co-planar with the front of the bat at the spliced end of the blade but gradually assumed a substantially triangular cross section along the length of the bat towards the distal end. Shortly before reaching the distal end, the triangular cross section is truncated. This particular form of blade design is chosen to maximise the strength of the bat in the region of the blade which provide greatest leverage on the ball in use and is referred to as "the middle" of the bat.

Fig. 3 shows a handle for the cricket bat and Fig. 4 shows a crosssection of the handle.

The handle 2 comprises a substantially cylindrical core portion 10 with a V-shaped splice 3 at one end, which in use is used to join the handle to the blade. The substantially cylindrical core portion 10 is provided with a jacket 12 having a plurality of undulations 13 on its outer surface. The jacket 12 is formed of a thermo-plastics material which is injection moulded onto the core 10 which is formed of a resin-based composite material.

As the injection moulded liquid cools and solidifies, it shrinks onto the core to give a very tight interference fit. The undulations 13 have the general form of an annular sinusoidal

wave extending along the longitudinal axis of the handle and are thus distributed evenly along the length of the jacket outer surface 12. In use the handle can be provided with one or more further tubular rubber grips so that the handle has the same feel and look as a conventional bat handle.

When a ball strikes the bat, the impact of the ball causes a vibrational force to propagate along the length of the blade and into the handle. The vibration is to some extent damped by the material of blade and hence when the ball is truck in the middle of the bat, there is little if any discomfort. However, when the ball hits the bat in the vicinity of the splice, the vibrations propagate to the batsman's hands. It has been found that by incorporating the undulations onto the surface of the handle, the vibration force is attenuated to a large degree resulting in a better feel for the batsman. The core in this case provides the structure of the handle, and the jacket undulations dominate the vibration dampening.

The substantially cylindrical core 10 can be formed from a variety of materials such as carbon, glass fibre or aramid fibres set in a thermoses plastic resin such as polyester or epoxy resin. The jacket 12 can be formed from any one of a variety of engineering thermoplastics. The handle can be attached to the blade using a conventional adhesive such as cyano-acrilates, polyesters, epoxy, silicone or polyurethanes. It is possible to vary the damping characteristics by varying the type and thickness of the adhesive used. As the core is made of synthetic materials, it is simpler to "tune" the core by modifying its composition and thereby have a predictable performance, which is significantly harder than with traditional constructions, which are often still hand-made with the inevitable variations inherent in natural materials. The weight of the handle may be varied by varying the density of the core by, for example, incorporating a lightweight filler material such as micro balloons, microspheres, or Cabosil (amorphous fumed silica) or similar expanded material. Using such methods, the weight of the handle can also be varied along its length to provide the desired balance.

The term substantially cylindrical is intended to cover cross-sections of handle which can be gripped by the hand but are not geometrically circular in cross-section. For example, the cross-section may be oval or elliptical, square or rectangular with rounded edges, or non-uniform.

The shape and amplitude of the undulations can vary. In particular, it has been established that the undulations can have a variety of curve forms or even a triangular wave form. In general, the sinusoidal form shown in the drawings is preferred as it provides sufficient vibration damping without impairing the comfort of the grip. The dimensions of the undulations shown will typically be about 0.5 to Imm and the separation of the peaks of adjacent undulations will be of the order of 12mm. The amplitude, frequency and number of undulations can be varied depending on the degree of damping required. It will be appreciated that the undulation illustrated in the drawing are exaggerated in order that the invention is more clearly understood. Although the exemplary embodiment is provided with undulations which extend along the length of the handle, the undulations could be restricted to less than the entire length and maybe restricted to just the portion of the handle adjacent the blade.

It would also be possible to apply the jacket to a conventional handle arrangement rather than a rigid core. The jacket would in general make a standard handle uncomfortably thick for most players, especially if a conventional rubber tube were placed over the jacket for comfort reasons. In these circumstances a conventional handle with a slightly smaller diameter could be used. Alternatively, the core and the jacket could be formed as a single piece, which may be machined from solid, or injection or compression moulded using a homogenous mixture of resin, fillers and reinforcing fibres. It is also possible with modern moulding techniques to mould the handle in one piece with a solid, hard core having a soft- touch outer skin forming the jacket.

Claims

- Claims

1. A handle for a cricket bat comprising a substantially cylindrical core having a splice end adapted to be joined to a blade to thereby form a cricket bat, wherein the handle is provided with a jacket or surface layer, which jacket or surface layer is provided with a plurality of undulations arranged on its outer surface, which undulations are adapted, in use, to dampen vibrations caused by a ball hitting the cricket bat.

2. A handle according to Claim 1, wherein the jacket or surface layer comprises a substantially cylindrical tube.

3. A handle according to Claim I or Claim 2, wherein the undulations comprise a sinusoidal wave.

4. A handle according to Claim 2 or Claim 3, wherein the undulations extend around the circumference of the jacket.

5. A handle according to any one of Claims I to 4, wherein the undulations extend along the entire length of the jacket.

6. A handle according to any one of claims I to 5, wherein the core includes a filler material whose density is different from the base material of the core.

7. A handle according to claim 6, wherein the filler material is of lower density than the base core material.

8. A cricket bat substantially as described herein, with reference to and as illustrated in the accompanying drawings.

8. A handle according to claim 6 or 7, wherein the density of the core varies across its diameter and/or along its length.

9. A handle according to any one of the preceding claims, wherein the core and jacket or outer layer are formed of a one-piece moulding.

10. A handle according to any one of claims 1 to 9, machined from a solid.

1 1. A cricket bat having a handle according to any one of Claims 1 to 10.

12. A method of damping vibrations in a cricket bat handle, comprising providing on the handle a plurality of undulations arranged on its outer surface, which undulations are adapted, in use, to dampen vibrations caused by a ball hitting the cricket bat.

13. A method according to claim 12, wherein the undulations comprise a sinusoidal wave. 14. A method according to claim 12 or 13, wherein the handle is formed of a one-

piece moulding.

15. A method according to claim 12 or 13, wherein the handle comprises a substantially cylindrical core and an outer layer or jacket which is injection moulded on to the core, where it shrinks on cooling to provide a tight interference fit.

16. A method according to claim 12 or 13, wherein the handle comprises a substantially cylindrical core and an outer layer or jacket which is bonded to the core by an adhesive.

17. A handle for a cricket bat substantially as described herein, with reference to and as illustrated in the accompanying drawings.