GB2294406A

GB2294406A - Improvements in or relating to sporting equipment

Info

Publication number: GB2294406A
Application number: GB9519167A
Authority: GB
Inventors: Brian Hughes; Roger Souders; Gary W Filice
Original assignee: Easton Sports Inc
Current assignee: Easton Sports Inc
Priority date: 1994-09-19
Filing date: 1995-09-19
Publication date: 1996-05-01
Anticipated expiration: 2015-09-19
Also published as: AUPM824094A0; ZA957835B; GB2294406B; GB9519167D0

Abstract

A bat having a blade 20, 22 and a handle 23 disclosed. The bat includes at least three pre-forms, each pre-form being separately overlaid with at least one layer of impregnable material and the pre-forms on assembly being overlaid with at least one layer of impregnable material and the assembly impregnated with resin whereby to form a unitary bat structure. A method for forming a bat is also disclosed. The extension 24 of handle 23 forms part of the blade. <IMAGE>

Description

IMPROVEMENTS IN OR RELATING TO SPORTING EOUIPMENT The present invention relates to improvcmetits in or relating to sporting equipment.

The invention is particularly applicable to bats having a handle portion and a substantially planar blade for striking a ball.

It is convenient to hereinafter describe the invention in relation to a cricket bat although it is to be appreciated that the invention may be advantageously applied to other sporting equipment having similar characteristics including, for example, a rounders bat.

A cricket bat typically comprises a handle and a blade. The blade is typically a single piece of timber such as English willow. The handle is typically formed from a more flexible material and is generally a multi-pieced lamina construction of cane or similar flexible wooden malerial. The individual picces of the handle are typically scparated from one anothcr with thin layers of rubber or similar shock absorbent material commonly known as springs.

The springs are gcncr;lliy each arranged in a plane substantially parallel to the face of the blade and act to cushion jarring which may otherwise be transmilled through the handle to the batsman s hands on slriking a cricket ball.

The handle is typically fixed to the blade by insertion into a substantially V-shaped splice at the top of the blade. The blade is typically elongated having a substantially planar face for striking a ball. The back of the blade or non-striking portion is typically non-planar and may be gabled so as to he substantially thicker about the ccntral longitudinal axis than at the edges. A cricket bat blade may have one or more grooves or other indenlalions formed in the back of the bat to modify weight distribution and ball striking characteristics.

A cricket bat typically extends from a rounded toe portion longitudinally to a shoulder portion at which the blade merges with the handle. The handle which extends longitudinally from the blade and is intended to he gripped hy the batsman is generally substantially cylindrical although it may be somewhat oval in cross-section in the vicinity of the shoulder.

The blade of a cricket bal is typically formed from a single piece of solid willow which tends to be somewhat unyielding whereas the handle is more flexible and the springs facilitate limited torsional flexing as well as cushioning the shock of the ball impacting on the blade so as not to jar the hands of the batsman. As top quality willow becomes more difficult to obtain, the qualities of a typical cricket bat suffer accordingly. The preferred qualities include durability, even density, hardness, rebound, sweet spot localion and balance poinl or pick-up as well as handle flexibility. Consislency of manufacture is hampered by willow with poor or varying properties including holes, pits, flaws and varying grain density.

Such infcrior properties typically Icad to reduced bat performance and limited pgt fr.

Morcovcr, traditional willow bats are susceptible to variations in temperature and humidity and can degrade quickly if allowed to get wet and/or if left in the open, especially ovcrnighl.

Various attempts have been made to produce cricket bats from synthetic materials which enjoy enhanced durability and consislency while retaining the pick-up, [eel and striking qualities of a traditional bat. However, such attempts have not as yet been wholly successful. Attempts to dale have involved the one piece plastics moulding of a bat which may be acceplable as a child's toy but typically does not have the required properties for serious play.

It has also been proposed lo shcath the blade of traditional bats in plastics materials to improve durability, however the shealh has been found susceptible to cracking and insufficient lo provide adequate hall striking properties if covering a sub-standard blade.

Another proposal was to produce an aluminium bat. While this gave acceptable performance for juniors the sound emilled on striking a ball was discordant and the feel and sound imparted on striking the ball differed from that of a Iradilional willow blade. Such synthetic bats have accordingly been somewhat unsuccessful.

The present invention accordingly provides in one embodiment a bat having a blade and a handle, said bat including at least three pre-forms, each pre-form being separately overlaid with at least one layer of impregnable material, the assembled pre-forms being overlaid with al least one impregnaìcd layer of impregnable material and the assembly impregnated with resin, whereby to lolrn a unitary bat structure.

The present invention provides in another embodiment a hal having a blade and a handle, said bat including at least thrce pre-forms, each pre-form being separately overlaid with at least one resin imprcgnated layer of impregnable material and the assembled pre forms being overlaid with at least one resin imprcgnalcd layer of impregnable material, whereby to form a unitary bat structure.

The present invention provides in another embodiment a cricket bat including three pre-forms defining a blade and a handle, each pre-form being separately overlaid with a plurality of layers of uni-directional fibres, a first layer of said uni-directional fibres being laid over the blade of the bat and a second layer of said uni-directional fibres being laid over the first layer wherein the direction of the uni-directional fibres of said second layer is transverse to the direction of the uni-directional fibres of said first layer, the layers after laying being wrapped by a cover layer comprising a woven mat of reinforcing fibres, the fibres of said mat extending transversely to the directions of the uni-directional fibres of said first and second layers, said cover layer extending over said handle, the assembled pre-forms being overlaid with a plurality of further layers of uni-directional fibres, a first further layer of uni-directional fibres being laid over the blade of the bat and a second further layer of unidirectional fibres laid being laid over the first further layer wherein the direction of the unidirectional fibres of said second further layer is transverse to the direction of the unidirectional fibres of said first further layer, the further layers after laying being wrapped by a further cover layer comprising a woven mat of reinforcing fibres, the fibres of said mat extending transversely to the directions of the uni-directional fibres of said first and second further layers, whereby to form a unitary bat structure.

The present invention provides in another embodiment a method for forming a hal, the method including the steps of forming a plurality of pre-forms; separate overlaying each pre-form with al least one layer of impregnable material assembling the overlaid pre-forms in the intended shape of a finished bat; overlaying the assembled pre-forms with at least one cover layer of impregnable material; impregnating the impregnable material with curahle resin, and curing said resin whereby lo form a unitary bat struclure.

In another embodiment the present invention provides a method for forming a hat including threc pre-forms defining a blade and a handle, the method including the steps of: separately overlaying each pre-form with a plurality of layers of uni-directional fibres, a first layer of said uni-direaional fibres being laid over the blade of the hat and a second layer of said uni-dircclional fibres being laid over the first layer wherein the direction of the uni-directional fibres of said second layer is transverse to the direction of the uni-directional fibres of said first layer, wrapping said first and second layers after laying with a cover layer comprising a woven mat of reinforcing fibres, the fibres of said mat extending transversely to the directions of the uni-directional fibres of said first and second layers, said cover layer extending over said handle, assembling the pre-forms into the intended shape of a finished bat, overlaying the assembled pre-forms with a plurality of further layers of uni directional fibres, a first further layer of said uni-directional fibres being laid over the blade of the bat and a second further layer of said uni-directional fibres laid being laid over the first further layer wherein the direction of the uni-directional fibres of said second further layer is transverse to the direction of the uni directional fibres of said first further layer, wrapping the further layers after laying with a further cover layer comprising a woven milt of rcinlbrcin" fibres, tlie librcs of said mat extending transversely lo the directions of the uni-direelional fibres of said first and second layers, impregnating the wrapped assembly with resin, and curing the resin, whereby to form a unitary bat slructure.

A bat provided in accordance with the present invention is preferably of traditional form having a blade with a substantially planar face, a rounded toe portion, a gabled back and tapering at a shoulder from the blade to a substantially cylindrical handle. As with a traditional bat, the face of a bat according to the present invention is preferably substantially planar although the striking surface may comprise a shallow convex curve extending across the face with rounded edges. Similarly, the gabled back of the bat may include one or more grooves or other indentations which may aller the weight distribution and hence the pick-up and striking characteristics of the bat.

A bat according to the present invention preferably includes at least one handle preform. In one preferred embodiment, the handle pre-form incorporates a handle portion and a blade portion. The handle portion of the handle pre-form is preferably substantially cylindrical although it may he of varying diameter along its length. The handle portion may also he nared in the vicinity of the shoulder whereby to provide a smoolh transition belween the handle and the blade of the finished bal.

The blade ponion of the preferred handle pre-form preferably includes a face portion and a back portion corresponding to the face and back of the finished bat. Preferably the blade portion of the handle pre-form extends longitudinally Or the finished bat or at least for a major part of the Icngth of said bal.The blade ponion of a handle pre-form according to the present invention is preferably substantially rectangular in cross-section. The blade portion may incorporate a gabled cross-section corresponding to the gable at the hack of the finished bat. it is to be appreciated that the shape of the blade portion of the handle pre-form may vary consistent with variations in the shape of the gable and/or any grooves in the back of the bal. Otherwise, the blade portion is preferably of substantially constant cross-seelion along its length. It is also to be appreciated that in the shoulder region of the finished bat the cross-section of the blade portion of the handle pre-form preferably merges into the substantially cylindrical form of the handle.

The blade portion of a handle pre-form according to the present invention is preferably of similar width at the face to the diameter of the handle.

in addilion lo a handle prc-form, a bat according lo the present invention preferably incorporates a pair of edge pre-forms. Each edge pre-form preferably comprises a blade portion and a shoulder portion whereby in the finished hat the blade edge tapers and merges into the handle in substantially traditional Shape. Each edge preform may include a face portion and a back portion to correspond to the face and back of the finished bat as well as one edge portion to correspond to an outer edge of the finished bat. Each edge portion preferably extends from the shoulder to the toe of the finished bat. Each edge portion may make up a substanlial portion of the blade.Most preferably the edge portions together form more than 50% of the face of the blade in a finished bat according to the invention.

The edge portions are preferably mirror images of one another and may be assembled each on opposile sidcs of a preferred handle pre-form whereby to form the outline shape of a bat according to the present invenlion.

Wilh the exceplion of the shoulder region where the edge pre-forms taper into the handle portion of the finished product, the edge pre-forms are preferably of substantially constant cross-section along their length. Each edge pre-form may be substantially rectangular although the rectangle side corresponding to the back of the hat may be angled lo conform to the gabled back of a bat and the edges corresponding to the edge of the hat may be rounded as in the edge profile of a traditional cricket bat.

Each pre-form of a bat according to the present invention may comprise polymeric foam. Preferred polymeric foams include High Impact Rigid or Semi-rigid Polyurethane, Thermoplastic Blown Foam and Microsphere Syntactic Foams.

The preferred method of producing pre-forms for use in accordance with the present invention is to cast or mould the polymeric foam into the pre-form shape.

Each pre-form of a bat according to the present invention is separate overlaid with at least one layer of impregnable material. The impregnable material may comprise at least one, and preferably a plurality of, reinforcing fibre layers. Preferably at least two such layers comprise layers of uni-directional fibres. The adjacent layers of uni-direclional fibres may be laid transversely, and preferably substantially at right angles to one anolher. Most preferably one of the layers comprises fibres extending substantially longitudinally of the blade portion. Most preferably the other of the layers comprises reinforcing fibres laid substantially transversely of the blade portion.

It is particularly preferred in accordance with the present invention that the first layer of uni-directional fibres which is in direcl contact with the material of the pre-form extends longitudinally of the blade portion of each pre-form.

Onc laycr ot uni-diructional fibres prutcrably overlays only the lace portion of each pre-form. A separate layer of uni-directional fibres preferably overlays only the face portion and adjacent side portions of each pre-form according to the present invention. These layers preferably do not overlay the back portion of each pre-form according to the present invention but preferably substantially cover not only the side portions which correspond to the edge of the finished bat but also the side portions which are placed adjacent one another in assembling the pre-forms to form a bat.

The uni-directional fibre layers preferably only overlay the blade portions described and do not cxtend over thc handle portion of a handle pre-form according lo the present invention.

Preferably each pre-form provided according to the present invention is overlaid with a woven mat of reinforcing fibres which covers the entire surface of each pre-form.

The woven mat is preferably applied in addition to the uni-directional layers and most preferably overlays the two uni-directional layers on the face of each blade portion.

The woven mat is preferably overlaid on each pre-form so that the reinforcing fibres of the mat are at an angle, most preferably an angle of about 45 , to the directions of the uni-directional layers. The woven fibre layer preferably extends over the entire length of the handle pre-form and thercby substantially wraps the handle portion as well as the blade portion of the handle pre-form.

In onc particularly preferred arrangement according to the present invention, the handle portion of the handle pre-form is wrapped with a reinforcing fibre sock, preferably a braided sock. The sock preferably extends over the handle portion of the handle pre-form and projects over the blade portion for a short distance beyond the shoulder transition area.

Most preferably the sock layer extends not more than 2 inches beyond the upper extenl of the shoulder and most preferably about ih inch.

It has been found that by utilising uni-directional fibres only on the blade portions and concentrating their use on the face of the blade but not extending to the handle and by providing a woven layer and a knitted layer of fibres over the handle portion, the reinforcement and flexibility of the handle varies from that of the blade. It will be appreciated that variations in the layers including the type of fibre, the closeness of the weave or knitling, the number, density and orientation of the layers and other known physical characteristics will affect the flexibility and reinforcement characteristics of the handle and/or blade.

The pr-torms arc preferably wrappcd or overlaid in the manncr describcd with dry reinforcing fibres. The reinforcing fibres are preferably glass fibres with the unidirectional fibres preferably being E-glass fibres and the woven mat and sock being woven from tubular glass fibres. It is envisaged however that other types of reinforcing fibres may also be used in accordance with the present invention. By way of example, facing fibres ol woven Vectron and Kevlar can be included for increased durability and dampening. Carbon fibres can also be used to adjust flexibility and reduce the weight of the bat.

After overlaying the pre-forms in the manner described, the pre-forms are brought together whereby to assemble the shape of the finished bat. The pre-forms asscmbled in the intended arrangement of the finished product may be overlaid with at least one cover layer in the form of a further layer of reinforcing fibres. Preferably at least two further cover layers of reinforcing fibres are provided, most preferably a first cover layer of uni-directional fibres such as E-glass fibres is overlaid only on the face of the blade. The fibres are preferably overlaid from the toe to the shoulder of the bal. Most preferably a second cover layer of unidirectional fibres is overlaid transverscly of the blade. The second cover layer preferably extends over at least the face and edges of the finished bat.

The construction and arrangement is preferably such that a cover layer according lo the present invention is capable of covering the abutting surfaces of each pre-form.

In a particularly preferred arrangement, the assembled pre-forms including the transverse uni-directional reinforcing cover layers are overlaid with an addilional wrap of a tubular glass sock. The tubular glass sock preferably extends over the entire bat surface with the exception of the handle and is preferably arranged so that the fibres extend substantially transversely with respect to the uni-directional fibres in the cover layers.

After the pre-forms are covered with dry wrap, the assembled and wrapped preforms are installed into a mould tool and impregnated with rcsin through the Resin Transfer Moulding (RTM) method.

Synthetic resins known for drying and curing to form a hard surface may be used in accordance with the present invention. Particularly preferred fibreglass resins include Polyester, Vinyl Ester, Urethane and Epoxy resin.

It is particularly important that the resin employed to form a bat in accordance with the present invention is suilable for retaining the three pre-forms in a single unitary structure al the same lime as bonding the overlaid layers of reinforcing fibres to one-another and lo the underlying pre-forms.

As will be appreciated by those skilled in the an, a variety of reinforcing fibre overlay arrangements may be used in accordance with the present invention. By varying the type of overlay material, the number of layers and the direction of layers, the characteristics of the blade and the handle of a bat may be modified.

It is to bc apprcciatcd that Ihe bat provided by ihc present invention incorporates the pre-forms which remain an integral part of the finished product. Further, the handle is simultaneously moulded into place with the blade whereby the need for a separate splicing as in the traditional bat manufacture is avoided. Significant modification to the amount and direction of fibres through the handle section has been found to achieve varying degrees of flexibility independent of the blade portion of the bat and such variations are accordingly envisaged within the scope of the present invention.

To furthcr assist in the undcrsl; nding +f thc prcscnt invention, particularly preferred embodiments of the invention will now be described in relation to the accompanying drawings, in which: FIGURE 1 is a plan view of Ihree bat pre-forms according lo one preferred embodiment of the invention; FIGURE 2 is an end view of the bat pre-forms of Figure 1; FIGURE 3 is a plan view of the pre-forms of Figure 1 showing one layer of unidirectional fibres; FIGURE 4 is a plan view of the pre-forms of Figure 3 showing a second overlay; FIGURE 5 is a plan view of the prc-forms of Figure 4 overlaid with a woven mat of rcinforcing fibres; FIGURE 6 is a plan view of the handle pre-form of Figure 5 showing the handle portion wrapped with a reinforcing fibre sock;; FIGURE 7 is a plan vicw of the pre-forms of Figures 5 and 6 overlaid with a first cover layer of reintorcino fibres; FIGURE R is a plan view of the assembled prc.forms of Figure 7 overlaid with a second cover layer of tubular glass sock; FIGURE 9 is a side view or a finished hat according lo one preferred embodiment of the invention; and FIGURE 10 is an end view of the bat of Figure 9.

The drawings illustrate a bat 10 comprising a handle 11 and a blade 12. The handle 11 is substantially cylindrical and in the embodiment shown in Figures 9 and 10 includes an enlarged end-piece 13 which cnahles the handle to be bound with string in the traditional manner if desired. However, as can be seen from Figures 1 to 8, this feature is optional.

The bat 10 is elongated with a substantially planar face 14 for striking a ball. As hest seen in Figure 10, the back 15 of blade 12 is gabled so as to be substantially thicker aboul the central longitudinal axis than at the edges 16 and 17.

Bat 10 is substantially in traditional lorm having a substantially planar face 14, rounded toe portion 18, gabled back 15 and tapering at shoulder 19 from blade 12 to a substantially cylindrical handle 11. As with a traditional bat, face 14 of bat 10 comprises a shallow convcx curve extending transverscly across face 14. As seen in Figure 10, the curve is ralher shallow and accordingly the face may even appear from a brief examinalion to be substantially planar. Edges 16 and 17 are as best seen in Figure 10 curved in the form of a traditional bat.

In the preferred embodiment illustrated in Figures 1 through 8, bat 10 includes three pre-forms 20. 21 and 22. Pre-torms 20 and 22 are a pair of edge pre-forms and preform 21 is a handle pre-form. Handle pre-form 21 includes a handle portion 23 and a blade portion 24. The handle portion 23 is substantially cylindrical in cross section although it may be of varying diameler along its lenglh such as by including a knob portion 13. Blade portion 24 of handle pre-form 21 includes a face portion and a back portion corresponding to the face 14 and back 15 of bat 10. As clcarly seen in the drawings, blade portion 24 of handle pre-form 21 extends longitudinally of finished bat 10 from toe 18 to handle 11.As clearly seen in Figure 2, blade portion 21 is substantially rectangular in cross-section while including a gabled cross-section corresponding to the gable at hack 15 of finished bat 10.

Blade portion 21 is of similar width at face 14 to the diameter of handle portion 11.

Edge pre-forms 20 and 22 are mirror images of one anolher and each includes a face portion and a back portion to correspond to the face and back of the finished bat as well as one edge portion to correspond respectively to outer edges 16 and 17 of finished bat 10.

Edge portions 20 and 22 extend from shoulder 19 to toe 18 of finished bat 10. Each edge portion 20, 22 tapers into handle portion 21 at shoulder 19.

As best seen in Figure 2, each edge pre-form 20, 22 is substantially rectangular although the reclangle side corresponding to hack 15 of bat 10 is angled to conform to the gablcd hack 15 and edges corresponding to bat edges 16, 17 are rounded as in the edge profile of a traditional cricket bat.

The sequence of Figures 1 through 8 shows the build-up of hat 10 according to the method provided hy the present invention. In the preferred embodiment illustrated, preforms 20, 21 and 22 are each overlaid with a first layer of uni-directional E-glass fibres on face portion 14 as clearly shown in Figure 3. The fibres are laid substantially longitudinally along bat 10 (ie at 0 ). The fibres extend substantially the full length of edge pre-forms 20 and 22 but only extend substantially the length of the blade portion 24 of handle pre-form 21, ie to the vicinity of the shoulder 19.

As best secti in Figure A, the prclorms overlaid as shown in Figure 3 are preferably further overlaid with a second layer of uni-directional glass fibres extending across face 14 (ie 90 ). The uni-directional E-glass fibres extending transversely across face 14 also extend across the adjacent sides of each pre-form including edges 16 and 17 but do not extend, in the embodiment illustrated, across back 15. As with the first overlay of Figure 3, the second overlay of Figure 4 extends only over the blade portion 24 of handle pre-form 21.

The pre-forms of Figure 4 overlaid with uni-directional fibres in two directions are as best seen in Figure 5, wrapped with 45" woven tubular fibreglass which covers substantially the entire surface of each of prc-forms 20, 21 and 22. It is to he noted in particular that the glass weave covers substantially the entire length of handle pre-form 21.

Handle portion 23 of handle pre-form 1 may he wrapped with a 45Q tubular glass sock as shown in Figure 6. Preferably the tubular glass sock extends approximately % inch into the shoulder transition area 19 as is evident from a close examination of Figure 6. Such extension of the glass sock covering handle portion 23 into blade portion 24 of handle preform 21 has been found useful to achieve seleclive reinforcement and control over flexibility in the area of handle 11.

In accordance with the method provided hy the present invention, the preforms 20. 1 and 22 are overlaid in the manner indicated with dry rcintesrcing fibres. Cover overlaying the pre-forms in the manner described the pre-forms 20, 21 and 22 are brought together as shown in Figure 7 to assemble the shape of finished bat 10.

The assembled pre-forms are, as shown in Figure 7, overlaid with a first cover layer of 900 uni-directional E-glass wrap on face surface 14.

The assembled pre-forms wrapped with a first cover layer as illustrated in Figure 7 are then given an additional second cover layer in the form of an overwrap of 450 tubular glass sock covering the entire bat surface with the cxception of handle 10 in the manner illustrated in Figure 8. The tubular glass sock thus extends from toe 18 to shoulder 19 as clearly seen in Figure 8.

After pre-forms 20, 21 and 22 are covered with dry wrap in the manner illustrated, the assembled and wrapped pre-forms are inserted into a mould tool (not shown) and impregnated with resin using the RTM method. The manner of effecting such installation and impregnation with a synthetic resin of the type provided in accordance with the present invention would be well known to those skilled in the art.

As clearly seen from Figure 8, bat 10 provided in accordance with the present invention incorporates preft)rms 20, 21 and 22 which remain an integral part of finished bat 10. Further, handle 11 is simultaneously moulded into place with blade 12 whereby the need for separate splicing as in the traditional bat manufacture which is a potential poinl of weakness is avoided.

At!vinttgL's which havc hccii round with a cricket bit provided in accordance with the present invention and with the method provided herein include the ease of manufacture which lends itself to semi-automatic operalions and the repeatable properties allowing control over the characteristics of a particular bat. The continued availability of malerials that will continue lo improve and evolve and provide consistent quality is also a significant advanlage which may be provided in accordance with the present invention. As will be appreciated by those skilled in the art, such a product as may be produced in accordance with the present invention may also have improved durability with a resulting prolonged bat life and a bat which is less affected hy heat, humidity and other weather conditions.

While il has been convenient to describe the invention herein in relalion to particularly preferred embodiments, it is to be appreciated that other constructions and arrangements are also considered as falling wilhin the scope of the invention. Various modifications, alterations, variations and/or additions to the constructions and arrangements described herein are also considered as falling within the ambit and scope of the present invention as defined by the claims.

Claims

CLAIMS:

1. A bat having a blade and a handle, said bat including at least three pre-forms, each pre-form being separately overlaid with at Icast one layer of impregnahle material, the preforms on assembly being overlaid with al least one layer of impregnable material and the assembly impregnated with resin, whereby to form a unitary bat structure.

2. A bat according to claim 1, wherein said bat includes at least one handle pre-form and al least two edge pre-forms, said pre-forms when assembled approximalely corresponding to the shape of a finished bat.

3. A bat according to claim 2. wherein said handle pre-fllrm incorporates a handle portion and a blade portion, said blade portion extending longitudinally of said bat substantially from the toe of the bat to said handle portion.

4. A bat according to any one of claims 1 to 3, wherein said impregnable material comprises reinforcing fibres.

5. A bat according to claim 4. wherein said rcinforcing fibres are uni-directional fibres.

6. A hat according to claim 5, wherein adjacent layers of impregnable material are laid over said pre-forms transversely to one another.

7. A bat according to claim 6, wherein a layer of impregnable material is laid over at least a face portion of each pre-form in the longitudinal direction of the blade and an adjacent layer of impregnable material is laid over at least the face portion of each pre-form in a direction which is transverse to the direction of said first layer.

X. A bat according to any one of the prcccding claims, wherein each of said prc-forms is overlaid with said layers of impregnable material on only a face portion of each pre-form.

9. A bat according to any one of the preceding claims, wherein at least one of said layers of impregnable material is a cover layer comprising a woven mat of reinforcing fibres capable of covering the abutting surfaces of each pre-form or preform assembly.

10. A hat according to claim 9, wherein said reinforcing fibres of said woven mat are uni-directional fibres.

11. A bat according to claim 9 or 10, wherein said cover layer is capahle of being wrapped over substantially the entire blade portion of each pre-form or pre-form assembly.

12. A bat according to claim 9, 10 or 11, wherein said cover layer extends over the handle pre-form.

13. A bat according to any one of the preceding claims, wherein said resin comprises a fibreglass resin.

14. A bat according to any one of the preceding claims, wherein said pre-forms are formed from polymeric foam.

15. A bat having a blade and a handlc. sunslallli.llly is hcreinhcrore Jescribcd and with reference to any one or more of the accompanying drawings.

16. A cricket bat having a blade and a handle, said bat including al least three preforms, each pre-form being separately overlaid with at least one resin impregnated layer of impregnable material and the pre-forms on assembly being overlaid with at least one resin impregnated layer of impregnable malerial, whereby to form a unitary bat structure.

17. A bat according to any one of the preccding claims, being a cricket bat.

18. A cricket bat including three pre-forms defining a blade and a handle, each preform being separately overlaid with a plurality of layers of uni-directional fibres, a first layer of said uni-directional fibres being laid over the blade of the hat and a second layer of said uni-directional fibres being laid over the first layer wherein the direction of the unidirectional fibres of said second layer is transverse to the direction of the uni-directional fibres of said first layer, the layers after laying being wrapped by a cover layer comprising a woven mat of reinforcing fibres, the fibres of said mat extending transversely to the directions of the uhi-directional fibres of said first and second layers, said cover layer extending over said handle, the pre-forms on assembly being overlaid with a plurality of further layers of uni-directional fibres, a first further layer of said uni-directional fibres being laid over the blade of the bat and a second further layer of said uni-directional [ibres laid being laid over the first further layer wherein the direction of the uni-directional fibres of said second further layer is transverse to the direction of the uni-directional fibres of said first further layer, the further layers after laying being wrapped hy a further cover layer comprising a woven mat of reinforcing fibres, the fibres or said mat extending transversely to the directions of the uni-directional fibres of said first and second layers, the wrapped assembly being impregnated with resin, whereby to form a unitary bat structure.

19. A method for forming a bat having a blade and a handle. said method including the steps of: forming a plurality of pre-forms; separately overlaying each pre-form with at least one layer of impregnable material; assembling the overlaid pre-forms in the intended shape of à finished bat; overlaying the assembled pre-forms with at least one cover layer of impregnable material; impregnating the impregnable material with curable resin; and curing said resin whereby to form unitary bat structure.

20. A method according to claim 19, wherein said bat includes at least one handle preform and at least two edge pre-forms, said pre-forms when assembled approximalely corresponding lo the shape of a finished bat.

21. A method jccrding to claims r0, whcrcill said handle pre-form incorporates a handle portion and a blade portion, said blade portion extending longitudinally of said bat substantially from the toe of the bat to said handle portion.

22. A method according to any one of claims 19 to 21, wherein said impregnable material comprises reinforcing fibres.

23. A method according to claim 22, wherein said reinforcing fibres are uni-directional fibres.

24. A method according to claim 23, wherein adjacent layers of impregnable material are laid transversely to one another.

25. A method according lo claim 24, wherein, one layer of impregnable material is laid over at least a face portion of each pre-form in the longitudinal direction of the blade and an adjacent layer of impregnable material is laid over al least the face portion of each pre-form in a direction which is transverse lo the direction of said first layer.

26. A bat according to claim 25. wherein each of said pre-forms is overlaid with said layer of impregnable material on only the face portion of each pre-form.

27. A method according lo any one of claims 19 to 26 and further including the steps of: overlaying the face of each pre-form or pre-form assembly with a first cover layer of impregnable material in a direction longitudinally of the blade; and overlaying each pre-form or pre-form assembly with a second cover layer of impregnable material in a direction transverse to said first cover layer.

S. A method according to claim 27, wherein at least one of said cover layers comprises a woven mat of uni-directional reinforcing fibre capahle of covering the abutting surfaces of each pre-form or pre-form assembly.

29. A method according to claim 28, wherein said reinforcing fibres of said wovcn mat arc uni-direclional fibres.

30. A method according to any one of claims 27 to 29, wherein said cover layers are wrapped over substantially the entire blade portion of each prc-form or pre-form assembly.

31. A method according to any one of claims 27 to 30. wherein one of said cover layers extends over the handle pre-form.

32. A method according to claim 31, wherein said first cover layer extends over the handle pre-form.

33. A method according to any one of claims 19 to 32, wherein said resin comprises a fibreglass resin.

34. A method according to any one of claims 19 to 33, wherein said pre-forms are formed from polymeric foam.

35. A method lor forming a bat including thrce pre-forms defining a blade and a handle, the method including the steps of: separate overlaying each pre-form with a plurality of layers of uni-directional fibres, a first layer of said uni-directional fibres being laid over the blade of the bat and a second layer of said uni-directional fibres being laid over the first layer wherein the direction of the uni-directional fibres of said second layer is transverse to the direction of the uni-directional fibres of said first layer, wrapping said first and second layers after laying with a cover layer comprising a woven mat of reinforcing fibres, the fibres of said mat extending transversely lo the directions of the uni-directional fibres of said first and second layers, said cover layer extending over said handle, assembling the pre-forms into the intended shape of a finished bat, overlaying the assembled pre-forms with a plurality of further layers of uni directional fibres, a first further layer of said uni-ilirectional fibres being laid over the blade of the bat and a second further layer of said uni-directional fibres laid being laid over the first further layer wherein the direction of the uni-direclional fibres of said second further layer is transverse to the direction of the uni directional fibres of said first further layer, wrapping the further layers after laying with a further cover layer comprising a woven mat of reinforcing fibres, the fibres of said mat extending transversely lo the directions of the uni-direclional fibres of said first and second layers, impregnating the wrapped assembly with resin, and curing the resin, whereby to form a unitary bat structure.

36. A method for forming a bat having a blade and a handle, substantially as hereinbefore described and with reference to any one or more of the accompanying drawings.

37. A method according to any one of claims 19 to 36 wherein said bat is a cricket bat.