GB2498804A

GB2498804A - A cricket bat with hollow air cavity situated within the blade

Info

Publication number: GB2498804A
Application number: GB1201543.4A
Authority: GB
Inventors: Lindsay Dalkin
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-01-30
Filing date: 2012-01-30
Publication date: 2013-07-31
Also published as: GB201201543D0

Abstract

A cricket bat blade 3 is formed of a solid single piece of wood and includes an air space 4 situated within the blade. Preferably the blade includes openings in opposing sides with the air space 4 extending between the openings. Alternatively, the blade may include an opening in the top and/or bottom with the air space (4, fig 2) extending into the blade from one or both openings. Each opening may be provided with an insert or cover 5, which may include a breather opening 5 such as a bore or hole. Alternatively, the air space 4 may be sealed against exchange of air with the surrounding atmosphere. The air space 4 may be situated directly behind a compressed surface layer. A method of manufacturing the cricket bat blade may include inserting an incompressible but bendable material 6 into the air space 4 before pressing the blade.

Description

A Cricket Bat

Field of the Itivetition

The present invention relates to cricket bats, and in particular to a cricket bat having an improved co-efficient of restitution.

Background of the Invention

Cricket is a game dating back as early as 1700, with the earliest known Code being drawn tip by certain "Noblemen and Gentlemen" in 1744. Today the Marylebone Cricket Club (die MCC) is die accepted Guardian of the Laws of cricket.

Cricket is a game played with a bat and a ball between two opposing teams. In order to ensure fairness amongst players the Laws of cricket define certain features of a cricket bat. Any bat outwith the relevant Laws (if the cricket may not he used in a gaule of cricket played under those Laws.

A cricket hat is defined as having a handle and a blade.

According to the sixth Law, paragraph 4b, the blade must consist solely of \vOOd.

1 lie manufacture of cricket bats follows long established traditional techniques. The blade is made of willow In the manufacturing process, the cleft is passed through press rolls that exert pressure on the bitting surface. This results in the willow in the surface of the cleft being compressed by a factor of three.

Since each cleft of willow will have slightly different properties it is not possible to give definitive measurements, but typically a region of willow extending 3 to 6nmi from die surface of the cleft pre-compressioli will have been compressed to a denser and harder layer of about I to 2nin from the surface post compression. The density and elastic modulus of this surface layer is increased by a factor of about three.

Press four times at up to 2000 psi on the hitting surface of the bat. Back of bat sits in a support in press process.

The SC) created hard surface is the surface with which the hail is hit. This hard surface is needed so that the wi iow is not damaged, and also to retain the wlilows natural springiness. When the ball is hit the hardened surface layer hends away from the impacting hail, this deformation causing elastic deformation of the soft willow behind the hardened surface layer.

Tt has been noted that thc best batsmen replace their bats when they have scored around five hundred runs. They notice that the hail does not conic off the hat in the same way as in the earlier part of its life. It is believed that this is due to the region of willow behind the hardened layer itself becoming hardened due to the repeated impacts of ball on hat. The depth of the hardened surfitce therefore increases which means that the spring constant of the hardened layer changes.

In sport there is always a desire for individuals or teams to increase their chance of winning.

Tjence, there is desire to produce a better cricket hat, i.e. a hat that may hit a hail further or more accurately.

A number of proposals have been made to improve cricket bats.

For example, \X702005/01 8757 describes a cricket hat having a hollow hladc. The pcriphcral weighting of the hlade, and the hollow centre allowing the hitting face to deflect inwards is said to increase hitting distance and the site of the sweet spot. However, the blade is formed by bonding together thin layers of hirth in a laminated sucture. Hence, the blade is formed of wood and adhesive, not solely of wood and as such is not alloxved under die Laws of criket.

GB2394424 describes a cricket bat having a resilient rod extending from the handle into the hlade of the hat. The rod controls the way iii which the hlade flexes, making the "feel" more uniform.

Ho\vever, the rod is not \vood, and is not part of the handle as defined in the Laws of cricket and hence this hat can not he used.

GB2067078 and \VC)2011/092714 both describe hollow metal cricket bats. These cricket bats cannot he used under the Laws of cricket.

Summary of the Invention

According to a first aspect of the invention there is provided a cricket bat blade, wherein the blade is formed of a solid siigle piccc of wood and mci udes an air space, the air space being situated within the blade.

Ihe blade is most preferably formed of willow.

The blade may include openings in opposing sides thereof, the air space extending through the blade between the openings 1 be blade may include an opening in the top and/or thc bottom and the air space may extend into the blade from one or both of the openings.

Each openng may he provided with an insert. The air space may be sealed against exchange of air with the surrounding atmosphere. Alternatively, an insert may include a breather opening.

Preferably, the blade includes a compressed surface layer and wherein the air space is situated directly behind the compressed surface layer.

Preferably the air space is between 0.5mm and 10mm wide, and more preferably between 0.5mm and 5mm wide, and still more preferably between 0.5mm and 2.5mm wide.

A second aspect of the invention provitlesacricket hat including a blade according to the first aspect of die invention.

A third aspect of the invention provides a method of manufacturing a cricket bat blade according to the first aspect of the invention, the method including the step of inserting a keeper into the air space prior to pressing of the blade1 the keeper being substantially harder than the wood from which the blade is formed.

The blade of the invention and a cricket bat having such a blade provides a number of advantages.

First, the coefficient of restitution is increased and hence a ball incident on the Face of the blade will travel further for the same effort on the part of the batsman.

Second, the weight of the bat may be reduced, allowing the batsman to use the bat in a more deft Third, the bat will not become dead in the same way, because the hard surface is separated from the softer and largely uncompressed rear part of the bat. Hence, the incident energy of a ball hitting the face of the bat will not compress the rear part of the hat.

Brief Description of the Drawings

In the drawings, which illustrate preferred embodiments of the invention and are by way of

example:

Figure 1 illustrates front and side views of a cricket bat according to a first aspect of the invention; Figure Ia illustrates a side view of the cricket bat illustrated in Figure 1 pre-final pressing; Figure lb illustrates a side view of the cricket bat illustrated in Figure 1 post-final pressing; Figure 2 illustrates front and side views of a cricket bat according to a second aspect of the invention; Figure 2aillustrates a side view of the cricket bat illustrated in Figure 2 pit-final pressing; and Figure 2b illustrates a side view of the cricket bat illustrated in Figure 2 post-final pressing.

Detailed Description of the Preferred Embodiments

Figure 1 illustrates a first embodiment of a cricket hat I according to the invention. The cricket bat I comprises a handle 2 and a blade 3, the Made 3 being formed solely of wood, rnd preferably that wood is willow. The bladu 3 has an air space 4 formed thurein. The air spacc 4 is in the form a slot extending from one side of die hlade 3 to the other aid is situated such that it is üi the tegion of the sweet spot of the blade 3. 11 may he desirable to close off the openings to the air space 4, and this may he achieved by fitting inserts 5 into the opeiungs 4' of the air space. in the illustrated example, the inserts 5 are shown having borcs 5' cxtending therethrough. These bores are providcd to allow for the passage of alt between the di space. 4 and atmosphere.

FIgure 2 illustrates a second embodiment of a cricket bat I according to the invention. The cricket bat I comprises a handle 2 atd a Made 3, the blade 3 being formed sokly of wood, and preferably thtt wood is willow. The blade 3 has an tir space 4 fanned t]1erein. The air space 4 is in the form a slot extending from the base irno the Made 3 and is situated such that it is in the region of the sweet spot of the hladu 3. It may he desirable to close off the opellitig at the hasu of de hladu to thu air space 4, and this may he achieved by fitting an insctt 5 into the opening 4' of the air space 4. In the illustrated examp'e, the insert 5 is shown having a bore 5' extendhig therethrough. IIiis bore is provided to allow for the passage of air between the air space 4 and atmosphere.

In hoth the cricket bats shown the air space is situated just behind the region of the Nade 2 that is compressed as described above.

The invention also relates to a method of manufacture of a cricket hat. The method of manuFacture follows the same steps as followed in traditional method of cricket hat manuFacture but adds two additional steps. The first additional step is to form an aix spacc in thc blade. 1his may be done using a number of suitable wood working tools, and may depend on the width of the aft space. If the air space is very narrow, for exampk in the range of 0.5 to 3.0mm, and the air space extends across the width of the blade as in Figure 1, then the air space may be formed using the blade of a saw. If the air space is wider then a saw blade may riot he adequate and other tools sucE as mortisi rig tools may be required.

Where the air space is to be extend along the length of the blade, as shown in Figure 2, then it is likely that a mortising tool would be the appropriate wood working tool.

The second step of the method of the invention involves the use of a keeper 6, placed in the formed air space when the blade is subjected to the pressing process. The keeper will be formed of a material substantially incompressible, but nevertheless capable of bending. The keeper may be capable of flexing, i.e. after removal from the blade after the pressing steps, the keeper returns to its original shape, i.e. becomes flat, or alternatively, the keeper may need to be re-shaped to return it to a fiat configuration.

The keeper may comprise a metal or plastic plate for example. As illustrated in Figures lb and 2h, during the final pressing step a curve is pressed into the fitce of the blade. During this step the thickness of the keeper 6 remains the same hut its shape changes to correspond with the curve pressed iito the face of the blade, the thickness of blade material between the blade face and the opening remaining constant along the length of and across the width of the blade post pressing.

Claims

<claim-text>Claims 1. A cricket bat blade, wherein the blade is formed of a solid single piece of wood and includes an air space, the air space being situated within the blade.</claim-text> <claim-text>2. A cricket bat blade according to Claim 1, wherein the blade is formed of willow.</claim-text> <claim-text>3. AcricketbatbladeaccordingtoClaimlor2, whereinthebladeindudesopeningsinopposing sides thereof; the air space extending through the blade between the openings.</claim-text> <claim-text>4. A cricket bat blade according to Claim I or 2, wherein the bladc includes an opening in the top and/or the bottom and the air space extends into the blade from one or both of the openings.</claim-text> <claim-text>5. A cricket bat blade according toy preceding claim, whexein each opening is provided with an insert.</claim-text> <claim-text>6. A cricket bat blade according to Claim 5, wherein the air space is sealed against exchange of air with the surrounding atmosphere.</claim-text> <claim-text>7. A cricket bat blade according to ClaimS, wherein an insert includes a breather opening.</claim-text> <claim-text>8. A cricket bat blade according to any preceding claim, wherein the blade includes a compressed surface layer and wherein the air space is situated directly behind the compressed surface layer.</claim-text> <claim-text>9. A cricket bat blade according to any preceding claim, wherein the air space is between 03mm and 10mm wide 10. A cricket bat blade according to Claim 9, wherein the air space is between 0.5mm and 5mm wide.11. A cricket bat blade according to Claim 10, wherein the air space is between 0.5mm and
2.5mm wide.11 AcricketbatcomprisingahandleandabladeaccordingtoanyofClaimsltoll.13. A method of manufacturing a cricket bat blade according to any of Claims I toll, the method including the steps of inserting a keeper into the air space prior to pressing of the blade, the keeper being substantially incompressible and capable of bending; and ii) removing the keeper post pressing.</claim-text>