Baseball Bat

Abstract

A baseball bat having a sleeve surrounding a portion of the narrow exterior surface of the bat for prevention of scattering of splinters and wood projectiles should the bat shatter during use. The sleeve is formed of wound fabric and secured mechanically at both ends to the exterior surface of the bat. The securement using a groove or ridge and traverse fibers engaged with the sleeve allows the sleeve to stretch and absorb energy and prevents a total separation of the heavy end of the bat from the handle from becoming airborne where it could cause serious injury.

Description

This application claims priority to U.S. Provisional Patent Application No. 61/075,704 filed Jun. 25, 2008, and which is incorporated herein in its entirety by reference.

FIELD OF THE INVENTION

This disclosed device and method relate to the field of baseball bats. More particularly, the device and method herein provide for wooden baseball bats which are reinforced with fiber wrapped exteriors and a mechanical engagement of the fibers to the wooden bat, to thereby yield a bat which will prevent the separation of large and small pieces of wood from a shattered bat which otherwise would become dangerous projectiles. So reinforced, the bats help ensure the safety of players and spectators during such an occurrence.

BACKGROUND OF THE INVENTION

The game of baseball has long employed the use of wooden bats to strike handballs thrown by the pitcher. While college leagues and many little leagues have changed to metal bats, players at the professional level, in the minor leagues, and in other leagues continue to prefer hardwood bats for striking the ball.

In years past, most major league teams employed bats made of ash wood which occasionally break when striking a ball. More recently, the major league players have moved to employ maple bats instead of ash due to a perceived performance enhancement using bats made from this wood. However, maple has an inherent proclivity to fracture in a manner where little energy is absorbed by the bat yielding clean fractures. Such clean fractures and lack of energy absorption produce projectiles which travel further and at velocities which can cause severe injury should they strike a player, umpire, or a fan.

Whether maple or another wood, the projectiles formed by pieces of a shattered bat, tend to have sharp jagged fracture surfaces which are extremely dangerous to players, fans and crew members. Frequently, a separation of the wood forming the bat, caused by the force of the bat striking a ball, can send shreds of wood in many directions at high velocities. Players adjacent to the breaking bat, such as the batter and catcher, and the umpire, are at extreme risk of injury from the flying debris. However, even people many yards away, such as the pitcher, or spectators in the stands have been injured from the projectiles formed by flying wooden pieces of a shattered bat. Many have suffered injuries from penetration of the skin by wooden slivers, to broken jaws caused by the impact of large pieces of the broken bat flying at high velocities.

A bat will typically initiate failure in the thinner region of the handle and in the transition region from the handle to the barrel. When the ball strikes the bat near the end of the barrel or in the transition region, the forces of the impact cause an intense shock load that excites the fundamental bending mode of the bat. Bending of the bat in this manner puts high stresses on the exterior of the bat. If there is a flaw such as a crack near the surface, the crack can quickly propagate through the entire bat.

Maple wood has a generally uniform structure where seasonal layers are hard to distinguish. Ash on the other hand, has easily discernable distinct growth layers. These layers consist of early wood which is a soft and porous layer which grows during the warmer seasons, and late wood which is hard and dense and grows during the cooler seasons.

Because ash wood has a non uniform layering structure, when a bat made from ash wood fractures, the layers tend to separate creating a leaf spring structure. Cracks in an ash wood bat tend not to propagate through the hard and soft layers.

For maple bats, because maple has a uniform hard layer structure, cracks propagate readily through the bat section with little energy loss. Recent efforts by Major League Baseball to minimize the failure rates of maple wood bats include increasing the diameter of the handle and tapered region, and specifying a grain slope less than one inch over a twenty-inch bat length. Additionally, players must strike the ball with the face of the grain on the bat opposite what players would normally do with an ash bat.

Additionally, nine new rules were recommended in an effort to minimize maple bat failures. However, some of these rules will most certainly discourage players from using maple bats and manufacturers of bats will have a hard time surviving under the new rules if they continue the manufacture of maple bats. Further, maple wood inherently has a hard uniform structure so cracks can propagate through the wood regardless of the new rules and despite such rules, it can't be guaranteed that a player will in fact keep the bat rotated correctly.

Because maple bats do have the perceived advantage for being very hard and imparting more energy to the ball, they will continue to be more favored for use. This hardness is one reason players like them since a pitched ball will bounce or rebound off a harder bat with more velocity. Ash bats being softer, tend to absorb energy in the soft pores. Another reason maple bats are favored is that they tend not to dent or splinter at the barrel from prolonged use. Maple bats, even with their tendency to yield high velocity shards upon shattering, because of their perceived benefits, will be a popular choice of players in the foreseeable future. Consequently, it is important that they be made safer to ensure the safety of both players and spectators.

Attempts have been made in the past to strengthen bats by employing wrappings of synthetic materials and resins. While such wrappings generally contain smaller pieces of wood from a shattered bat, large pieces of shattered bats have sufficient mass to develop sufficient force to separate from conventional fabric and resin reinforcements which are simply adhered to the exterior surface of the wood bat.

As such, there exists an unmet need for a device and method yielding reinforced wooden baseball bats to protect players and spectators from flying debris. Such a device should be sufficiently light weight not to affect the bat balance, weight or natural frequency. Such a device should have sufficient mechanical engagement of the fiber wrapping employed to strengthen the bat, to also insure that large pieces of a shattered bat moving at higher forces, do not separate from the fiber engagement providing the restraint.

SUMMARY OF THE INVENTION

The disclosed device and method herein is directed to a method of bat reinforcement which yields a safer wooden bat and which does not alter its strength or performance. Using a method of fiber-wrapped reinforcement, the method herein yields a bat which has wrapped fibers in a mechanical engagement with small grooves formed in the exterior bat surface. The method provides a means to prevent large and small pieces of the bat formed, from becoming projectiles due to their high force during a bat fracture associated with a ball and bat impact.

It is desired in most baseball leagues where statistics on players and historical data as to performance are essential to the legacy of the sport, that the equipment that players employ over time will not change significantly. Such consistency allows for player records and statistics to be accurately compared over many decades.

With this in mind, the disclosed method and device provided thereby yields the reinforcement and containment necessary to prevent shards and projectiles from becoming airborne, while still maintaining the bat itself sufficiently similar in performance to non-reinforced bats. If a bat and ball impact would cause a non-reinforced bat to break, then that same interaction is desired for the reinforced bat in order to maintain the continuity of the equipment used by the players in accordance with previous equipment. However, after the break, a bat formed by the method herein will cause a containment of the larger shards and projectiles which would conventionally separate from the bat.

In the current preferred mode of the device, this similar behavior is accomplished by one or a combination of:

1) Minimizing the amount of reinforcement to less than 1% the mass of the bat.
2) Minimizing the modulus of the fiber employed for reinforcement.
3) Employing high strength fiber so as to absorb energy on a shatter of the bat.
4) Employing a fiber matrix interface allows the fiber to absorb energy efficiently during a bat failure.
5) Employing some type of mechanical engagement of traverse fibers to engage them mechanically to the wood of the bat in at least two positions thereby providing a capture component, and to maintain the fiber matrix in position around the thinner portions of the bat which are most liable to shatter and to prevent larger sections from separating.

The disclosed device employs fibers which are wrapped around the exterior of the bat. Where safety is of the sole focus of the reinforcement, then the fibers selected should have a low modulus of elasticity and high strength. The lower modulus will minimize its effect on the bat's fundamental frequency or strength to maintain consistency of performance with bats of prior years. With a higher modulus, the fiber will increase its participation in a ball strike by absorbing more load.

The fiber tows are wound by hand or by CNC filament winder. The fibers are preferably wound along an axial direction between 0°+/−30° (low angle fibers) relative to the long axis of the bat, and traverse to the long angle fibers from +/−30° to +/−50° (off-axis fibers). The low angle fibers are wound first and this step may employ jigs or pegs or other means to temporarily maintain the fibers in place until the off-axis fibers are engaged. The traverse off-axis fibers are subsequently wound and employed to hold the low angle fibers snug against the exterior bat surface thereby forming a containment component for shards or pieces of the bat which might separate during impact with the ball.

The wrapping of fibers extends in the favored mode, substantially from the knob end of the bat, to about 12 inches from the distal end of the barrel of the bat. The distance of the wrapping between both ends thereof is substantially between 55-65 percent of the bat total length with 62% of the bat length having been tested to be especially effective and therefor being an especially preferred length for the wrapping.

The fibers forming the wrapping to yield the containment component, may be any fiber suited to the task and goal with two favored fibers being Kevlar or Spectra. Of course those skilled in the art will realize that other fibers may be very well suited to the task of forming a containment component mechanically engaged to a bat at both ends, and all such fibers as would occur to those skilled in the art are anticipated within the scope of this application.

Once wound on the bat, a thin epoxy layer or polyurethane or varnish or other coating appropriate to the task is applied to the bat and to the wound fibers to lock the fibers in place to form the containment component for flying shards and debris in the event of a break, and to provide the bat with a durable finish.

To maintain the bat within the scope of bats employed in previous seasons, preferably the mass of the reinforcement is typically less than 1% the mass of the bat to which it is engaged. The effect of the reinforcement on strength and stiffness of the bat should be minimal however. Rather than yield a stronger, stiffer bat which as noted would inhibit comparison of player statistics with those of the past, the ultimate objective of the formed reinforcement is to retain shattered pieces of the bat from becoming airborn. This is accomplished by the fiber wrap forming a containment component mechanically engaged at two ends to the bat and restraining separating bat pieces from becoming airborne.

The following table summarizes the properties of several different fiber types. The fiber with the highest specific tensile strength is the Spectra 900 fiber which is a high-strength, lightweight fiber, formed of polyethylene. A polyethylene fiber with these performance characteristics is preferred because it is very lightweight, has a high strength, and is durable and translucent when coated with a clear matrix.

Another good trait of polyethylene fiber such as Spectra 900 is that the surface finish of the fiber is smooth and it thus does not adhere well to resins. This slippage or non adherence is important in that it allows the fibers to slip through their matrix during a bat failure allowing the fiber forming the containment component to absorb more energy.

Another preferred fabric for wrapping the bat is formed of aromatic polyamide such as Kevlar-29 fiber. This type of fiber also has very high tensile strength and is lightweight. It has a modulus lower than the polyethylene fabric such as the Spectra 900 which makes it a good candidate for the device herein. Aromatic polyamide however, is generally not translucent when coated with an epoxy and it also yields a fiber matrix strength higher than the polyethylene fiber. A table below provides examples of fibers and their respective characteristics.

TABLE 1
Fiber Property Comparison (SI Units)
		Density	Modulus	Tensile	Specific TS
Fiber	Description	(g/cm{circumflex over ( )}3)	(GPa)	Strength (GPa)	(Gpa * cm{circumflex over ( )}3/g)
Spectra 900	HS Polyethylene	0.97	75.0	2.5	2.6
Kevlar-29	Aromatic Polyamide	1.44	54.0	2.4	1.7
E-Glass	Silica Glass	2.55	72.4	3.4	1.4
T300	Carbon	1.76	231.0	3.7	2.1
Steel Wire	Steel	7.76	200.0	2.0	0.3
(US Customary Units)
		Density	Modulus	Tensile	Specific TS
Fiber	Description	(in/lb{circumflex over ( )}3)	(Msi)	Strength (Ksi)	(Ksi * in{circumflex over ( )}3/lb)
Spectra 900	HS Polyethylene	0.035	10.9	363	10352
Kevlar-29	Aromatic Polyamide	0.052	7.8	348	6694
E-Glass	Silica Glass	0.092	10.5	500	5435
T300	Carbon	0.064	33.5	531	8353
Steel Wire	Steel	0.280	29.0	285	1018

As noted, while the device and method herein is intended to form a containment component on a bat to act as a safety net to retain wood projectiles on failure of the bat, this type of fiber reinforcement can also be used to increase strength or performance if desired and allowed. By simply selecting a fiber with higher modulus and better a stiffer, stronger, fiber-matrix interface strength such as a carbon fiber T300, and by increasing the mass percentage of the reinforcement primarily in the low angle direction, a significant increase in the fundamental bending mode and strength can be attained. However, such enhancements would obviously have to be league-approved to be employed as they would form a bat with strength characteristics inconsistent with bats of the past.

With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the formed bat device, and methods herein forming the device, shall include variations in size, materials, shape, form, function and manner of operation, assembly and use, which would be readily apparent and obvious to one skilled in the art. Consequently all equivalent relationships to those illustrated in the drawings and described in the specification which would occur to those skilled in the art are intended to be encompassed by the present invention. Therefore, it should be understood that the foregoing summary and following detailed description are to be considered as illustrative only of the principles of the invention.

Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and method of formation shown and described, and accordingly, all suitable modifications and equivalents which may be resorted to, shall be considered as falling within the scope of the invention.

Still further, it is to be understood that the phraseology and terminology employed herein are for the purpose of description of the principals of the device and method herein, and should not be regarded as limiting in any fashion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a side view of a bat having the formed containment component thereon covering a portion of the bat and in an engagement with the bat at two formed recesses or surface level changes.

FIG. 2 depicts a slightly raised exterior surface providing one manner of physical engagement of an end of the attached containment component.

FIG. 3 depicts a groove formed in the bat exterior surface adjacent to the knob end and providing another mode of engagement the end of the containment component formed by the fibers.

FIG. 4 shows a side view of a preferred mode of a baseball bat showing the containment component formed of wrapped fibers axially disposed in the range at substantially 0° and with fibers traverse to the axis at an angle of +/−45° with end portions of fibers anchored in grooves.

FIG. 5 depicts another mode of the device herein showing the fiber wrap formed of planar fibers in a double spiral and two ends engaged in grooves.

FIG. 6 depicts a single spiral wrap of planar fibers in a spiral terminating within the opposing grooves on the surface of the bat.

FIG. 7 shows a preferred mode of the device having the fiber wrap formed of both axially disposed fibers encompassed by a single spiral wrap holding the axial fibers and place and with fibers anchored in the grooves of the surface.

FIG. 8 depicts a mode of the device wherein the fibers are wound at +/−10° in the low angle and +/−50° in the high angle.

FIG. 9 depicts a mode of the device wherein the mesh net forming the containment component is knitted or woven in a circular tube and then heated or otherwise shrunk onto the bat and into the grooves.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to the drawings in FIGS. 1-9, wherein similar parts are identified by like reference numerals, there can be seen in the various figures, depictions of favored modes of the device 10 yielded by the method herein.

All of the embodiments of the device 10 yielded by the method herein, employ fibers 14 to form a capture component 16 around the narrower portions of a baseball bat 12. As shown in FIG. 1, in a bat 12 having a conventional length “L” the capture component 16 in the preferred mode has a length L1 covering more than half the length L of the bat 12. Currently the capture component is formed to have a length L1 which surrounds between 45-65 percent of the length L, of the bat 12. A particularly preferred capture component 16 length L1, is substantially 62 percent of the bat length L.

The formed capture component 16 additionally employs traverse windings of the fibers 14 at both ends to mechanically engage the capture component 16 to the bat 12. This engagement allows broken parts of the bat to slip but provides a means to maintain larger broken sections of the bat 12 proximate to each other should a severe break occur as the fibers 14 forming the capture component 16 will stretch but hold. This engagement of the two ends of the capture component 16 overcomes the shortcomings of prior art which can allow larger portions of a broken bat 12 to shear from their engagement with the fibers 14 which are simply wound onto the bat and adhered without any mechanical connection to prevent such an occurrence.

As shown in FIG. 1, the capture component 16 extends from a first end 18 adjacent to the knob 20 portion of the bat 12 to a second end 22 and encircles the mid section of the bat 12. At the first end 18 of the bat 12 as shown in FIG. 3, a recess 25 is formed on the exterior surface of the bat 12 by either cutting a groove into the surface or forming a small ridge 17 as shown in FIG. 2. These formed recesses 25 at both ends of the capture component 16, provide a mechanical engagement of both ends of the capture component 16 to the bat 12 at the recess 25 positions through the winding of fibers 14 traverse to the axis 28 and into the recesses 25.

In FIG. 4, there is shown a capture component 16 in a preferred mode of a baseball bat 12 wherein the mesh net forming the capture component 16 is formed by the axially disposed and traverse wound fibers 14. As depicted, the axially disposed fibers 14 are positioned at substantially 0° with the traverse wound fibers 14 being wound spirally at angles substantially of +/−45°. Fibers 14 at the first and second ends of the capture component 16 are substantially perpendicular to the axis 28 and engaged within the recess 25 formed by a groove 23 or raised portion 17 of the bat 12. Thus, the recesses 25 provide an anchoring means of both ends of the capture component 16 to the portions of the bat 12 where they are engaged.

As is well known in the art, bats 12 tend to break at the thinner sections of the bat 12 which would be completely covered by the capture component 16 and thereby prevented from becoming airborn projectiles upon a break. In a serious break of the bat 12, larger sections can dislodge and due to their larger mass, can become airborn for substantial distances. This is especially true of sections on the distal end 19 of the bat 12 where the second end 22 of the capture component 16 is engaged in the recess 25. The traverse fibers 14 engaged within the recesses 25 provide a means to restrain such larger portions of the bat 12 which heretofore would shear from the engagement of the fibers 14 and glue, epoxy, or other resinous coating holding the fibers 14 to the bat 12.

The capture component 16 between its two ends, serves as a net to capture wood pieces which might become airborne on a break and also to protect the user from the sharp points that can develop on a complete break of the bat 12 in the thinner section surrounded by the capture component 16.

There are many configurations of the capture component 16 that can be wound and woven and those skilled in the art will no doubt realize such upon review of this specification. Any combination of axial and traverse fibers 14 to form the capture component as would occur to those skilled in the art are anticipated within the scope of this application. The overriding factor is that at least the second end 22 of the capture component 16 should be engaged by fibers 14 traverse to the axis 28 and engaged with a recess 25 formed by either a grove 23 as in FIG. 3, or ridge 17 as in FIG. 2, formed on the bat 12 surface. Additionally, the fibers 14 may be of any dimensional characteristics, be it planar or round or oval, so long as they are engaged to form the capture component 16 and engaged with at least one, and preferably both recesses 25.

As shown in FIG. 4, the configuration features axially disposed fibers 14 encircled by traverse fibers 14 in a double spiral to form the capture component 16. The ends 18 and 22 are engaged in the recesses 25 which would be formed on the bat 12 surface.

Another preferred configuration is that of FIG. 5 wherein the capture component 16 is formed of another mode of the device herein showing the fiber net formed of planar fibers 14 in a double spiral wind and without the axially disposed fibers 14. At the first end 18 and second end 22 of the formed capture component 16 the fibers 14 are engaged with the recesses 25. The spirals run at +/−45 degree angles to the axis 28 in a preferred mode.

In a third preferred configuration of the capture component 16 in FIG. 6, the capture component 16 is formed in a single spiral wrap of planar fiber 14 and terminating at both ends 18 and 22 in a traverse engagement of the fibers 14 in the formed recesses 25.

Yet another preferred mode of the device of FIG. 7 depicts the capture component 16 formed of fibers 14 positioned axially which are encompassed by a single spiral wrap of fiber 14 holding the axial fibers 14 in place. Both ends 18 and 22 as in all modes of the device 10 are anchored to the bat 12 by fibers 14 engaged traverse to the axis 28 and engaged with the recesses 25 properly positioned at the ends and formed by groves or ridges or other means.

Finally, in another mode of the device 10 in FIG. 8, the capture component 16 is formed of axially positioned fibers at substantially a +/−10° angle to the axis 28 and traverse fibers 14 wound to hold the axial fibers 14 in place at +/−50° from the axis 28. Both ends 18 and 22 of the formed capture component 16 have fibers 14 are engaged in the recesses 25 formed preferably perpendicular and traversing the axis 28.

All fibers 14 engaged in the recesses 25 of the embodiments herein may be one or a combination of the axial and traverse fibers 14 or at a position wherein an axial fiber 14 may transition to a traverse fiber 14 if wound in that fashion, with the overriding factor being a secure engagement of both ends 18 and 22 of the formed capture component 16 into recesses 25 in the bat surface formed by cutting grooves or forming ridges and engaging the fibers 14 on the opposite side of the ridge from where the end 18 or 22 of the capture component 16 abuts it.

There is shown in FIG. 9 another mode of the device 10 wherein the capture component 16 may be preformed or woven slightly larger than the bat 12 circumference and slid over one end. Once thereon, the capture component formed of the fibers 14 in the desired configuration may be shrunk by heating the fibers 14 wherein the ends 18 and 22 will engage with the recesses 25.

It is to be understood that elements of different construction and configuration and different steps and process procedures and other arrangements thereof, other than those illustrated and described, may be employed for providing the baseball bat with fabric formed safety net and reinforcement and any method herein within the spirit of this invention.

As such, while the present invention has been described herein with reference to particular embodiments thereof, a latitude of modifications, various changes and substitutions are intended in the foregoing disclosure, and it will be appreciated that in some instance some features of the invention could be employed without a corresponding use of other features without departing from the scope of the invention as set forth in the following claims. All such changes, alternations and modifications as would occur to those skilled in the art are considered to be within the scope of this invention as broadly defined in the appended claims.

Claims

1. A baseball bat comprising:

a baseball bat having a center axis therethrough and having a length extending from a knob on a first end to a distal end, said baseball bat having a central portion in-between said first and second ends and having an exterior surface;

a sleeve circumferentially engaged upon said exterior surface, said sleeve extending for a sleeve length between a first end adjacent to said knob, to a second end extending to said central portion; and

means to mechanically engage said second end with said exterior surface, whereby said distal end after a separation of from said first end of said baseball bat occurring in said central portion, is restrained by said sleeve.

2. The baseball bat of claim 1 additionally comprising:

means to mechanically engage said first end with said exterior surface of said bat at a position adjacent to said knob.

3. The baseball bat of claim 1 wherein said means to mechanically engage said second end with said exterior surface comprises one of a ridge rising above said exterior surface or a recess formed into said exterior surface and having said first end constrictively engaged over said ridge or within said recess.

4. The baseball bat of claim 2 wherein said means to mechanically engage said first end with said exterior surface comprises one of a ridge rising above said exterior surface or a recess formed into said exterior surface and having said second end constrictively engaged over said ridge or within said recess.

5. The baseball bat of claim 1 wherein said sleeve is formed of fibers wound around said exterior surface of said baseball bat.

6. The baseball bat of claim 2 wherein said sleeve is formed of fibers wound around said exterior surface of said baseball bat.

7. The baseball bat of claim 3 wherein said sleeve is formed of fibers wound around said exterior surface of said baseball bat.

8. The baseball bat of claim 4 wherein said sleeve is formed of fibers wound around said exterior surface of said baseball bat.

9. The baseball bat of claim 3 wherein said means to mechanically engage said first end additionally comprises secondary fibers engaged with said first end and running traverse to said center axis.

10. The baseball bat of claim 4 wherein said means to mechanically engage said first end and said means to mechanically engage said second end, both comprise secondary fibers engaged with said first end and second end respectively, and running traverse to said center axis.

11. The baseball bat of claim 8 wherein said means to mechanically engage said first end and said means to mechanically engage said second end, both comprise secondary fibers engaged with said first end and second end respectively, and running traverse to said center axis.

12. The baseball bat of claim 1 wherein said sleeve length is between 45 to 65 percent of said length of said bat.

13. The baseball bat of claim 7 wherein said sleeve length is between 45 to 65 percent of said length of said bat.

14. The baseball bat of claim 8 wherein said sleeve length is between 45 to 65 percent of said length of said bat.

15. The baseball bat of claim 5 wherein a portion of said fibers are wrapped at an angle to said center axis between 40 and 60 degrees.

16. The baseball bat of claim 8 wherein a portion of said fibers are wrapped at an angle to said center axis between 40 and 60 degrees.

17. The baseball bat of claim 11 wherein a portion of said fibers are wrapped at an angle to said center axis between 40 and 60 degrees.

18. The baseball bat of claim 16 additionally comprising a secondary layer of said fibers underneath said fibers wrapped at said angle, said secondary layer of fibers being substantially parallel to said center axis.

19. The baseball bat of claim 17 additionally comprising a secondary layer of said fibers underneath said fibers wrapped at said angle, said secondary layer of fibers being substantially parallel to said center axis.

20. A method for constructing the bat of claim 10, comprising the steps of:

forming one of a ridge or a groove at positions to be occupied by said first end and said second of said sleeve;

winding said fibers around said bat to form said sleeve circumferentially upon said exterior surface of said bat; and

winding said secondary fibers around said bat and engaging said first end and said second end to said ridge or said groove.