Racket with improved handle assembly

Abstract

The present invention relates to a racket having an improved handle assembly, including a tubular frame made of a fiber composite material, a sleeve, and a bottom cap. The frame includes a first end region, a second end region, and an intermediate region. The handle portion includes a distal region, a proximal region, and a central region between the distal region and the proximal region of the handle portion. The central region and the proximal region of the handle portion each have an outer surface defining a first cross-sectional area and a second cross-sectional area. The second cross-sectional area is greater than the first cross-sectional area. The sleeve is coupled to and extends longitudinally over the central region of the handle portion but does not extend over the proximal region of the handle portion. The bottom cap is secured to the proximal region and includes a peripheral wall, and the peripheral wall extends over the sleeve for less than one-half of its length.

Description

Technical Field

[0001] This invention generally relates to a sports racket. More specifically, it relates to a sports racket. In particular, it relates to a handle assembly for a sports racket, wherein the handle assembly includes a handle portion having an enlarged proximal region. Background Technology

[0002] Sports rackets such as tennis, wallball, squash, and badminton rackets are well-known and typically include a head portion that attaches to the handle assembly. The head portion supports the string bed, which has multiple main strings interwoven with multiple cross strings. The handle assembly typically includes a handle, a pad, a bottom cap, and a grip.

[0003] The pad is typically made of a rigid material extending to the proximal end of the handle portion, and the bottom cap is attached to the pad near the proximal end of the racket. In some cases, over time, the bottom cap may shift, loosen, or otherwise detach from the racket pad. Therefore, there has been a need for a racket with an improved handle assembly that enhances the durability and reliability of the racket's handle and further prevents the bottom cap from shifting or detaching from the racket's handle portion. Summary of the Invention

[0004] This invention provides a sports racket comprising a tubular frame, a pad, and a bottom cap formed of a fiber composite material. The frame includes a first end region, a second end region, and a middle region. The first and second end regions extend side-by-side with respect to each other in a handle portion, and the middle region forms part of a head portion. The handle portion includes a distal region, a proximal region, and a central region located between the distal and proximal regions of the handle portion. The central and proximal regions of the handle portion each have outer surfaces defining a first and a second cross-sectional area, respectively. The second cross-sectional area is larger than the first cross-sectional area. The pad is attached to the central region of the handle portion and extends longitudinally over the central region, but not over the proximal region of the handle portion. The bottom cap is securely fixed to the proximal region of the handle portion. The bottom cap includes a proximal wall and a surrounding wall. The proximal wall has a length extending from the proximal wall and surrounding the proximal region of the handle portion such that less than half of the length of the proximal wall extends over the pad.

[0005] According to a preferred aspect of the invention, a handle assembly for a sports racket includes a handle base, a pad, and a bottom cover formed of a fiber composite material. The handle base includes a distal region, a proximal region, and a central region located between the distal and proximal regions of the handle base. The central and proximal regions of the handle base each have outer surfaces defining a first cross-sectional area and a second cross-sectional area, respectively. The second cross-sectional area is larger than the first cross-sectional area. The proximal region includes a proximal end and a sidewall forming a polygonal cross-sectional area. The sidewall has a first side portion and a second side portion. The first side portion extends from the proximal end and has a length of at least 10 mm. The first side portion defines a consistent polygonal cross-sectional area along its length. The second sidewall portion defines a cross-sectional area that varies from the first sidewall portion to the central region of the handle base. The second sidewall portion has a length of at least 10 mm. The pad is attached to the central region of the handle base and extends longitudinally over the central region but not over the proximal region of the handle. The bottom cover is fixed to the proximal region of the handle base. The bottom cover includes a proximal wall and a peripheral wall. The proximal wall has a length extending from the proximal wall and around the proximal region of the handle portion, such that less than half the length of the proximal wall extends over the pad.

[0006] The invention will be more fully understood through the following detailed description, in conjunction with the accompanying drawings, wherein like reference numerals denote like parts. Attached Figure Description

[0007] Figure 1 This is a front perspective view of a racket according to one embodiment of the present invention.

[0008] Figure 2 This is a side view of a portion of a stack or arrangement of fiber composite layers surrounding the capsule and mandrel before molding.

[0009] Figure 3 This is a top-side perspective view of a stack of fiber composite layers, with the mandrel removed, showing a stack of layers bent into an approximate racket shape, as well as a stack of yoke fiber composite layers.

[0010] Figure 4 This is a top-side perspective view of the fiber composite material layer stack in Figure 7 before it is placed into the racket molding die.

[0011] Figure 5 This is an exploded top view of the fiber material layers placed in the racket molding mold.

[0012] Figure 6 yes Figure 1 A perspective view of the side end of the handle portion of the racket shown.

[0013] Figure 7A It is along Figure 6 A transverse sectional view taken along the centerline 7A-7A.

[0014] Figure 7B It is along Figure 6 A transverse sectional view taken along the centerline 7B–7B.

[0015] Figure 7C According to an alternative embodiment of the present invention, along Figure 6 A transverse sectional view taken from line 7B–7B.

[0016] Figure 8 yes Figure 1 A top view of the handle portion of the racket shown.

[0017] Figure 9 yes Figure 1 A side view of the handle portion of the racket shown.

[0018] Figure 10 yes Figure 1 The longitudinal sectional view of the handle assembly of the racket shown.

[0019] Figure 11 This is a top perspective view of the central and proximal regions of the handle portion of a racket according to another embodiment of the present invention, and a longitudinal sectional view of the bottom cover.

[0020] Figure 12 and Figure 13 This is a top perspective view of the central and proximal regions of the handle portion of a racket according to other embodiments of the present invention, and a longitudinal sectional view of the bottom cover.

[0021] Figure 14 This is a top perspective view of the central and proximal regions of the handle portion of a racket according to another embodiment of the present invention, and a longitudinal sectional view of the bottom cover.

[0022] Figure 15 This is a top side perspective view of the racket torsional stability testing assembly and the racket undergoing torsional stability testing, with a first weight applied to the racket torsional stability assembly.

[0023] Figure 16 yes Figure 15 A perspective view of the first end side of the racket torsional stability test assembly.

[0024] Figure 17 yes Figure 15 The image shows a racket torsional stability test assembly and a top side perspective view of a racket undergoing torsional stability testing, with the first weight removed from the racket torsional stability assembly. Detailed Implementation

[0025] refer to Figure 1 In general, sports rackets are represented by 10. Figure 1 The racket 10 is configured as a tennis racket; however, the invention can also be formed as a racket for other types of sports, such as a short-handled wallball racket, squash racket, or badminton racket. The racket 10 includes a frame 12 defining a head portion 14 and a handle assembly 16. In one embodiment, the frame 12 may further include a pair of throat tubes 18 forming a throat region 20 between the head portion 14 and the handle portion 40.

[0026] Frame 12 is preferably made of a robust, lightweight material such as a fiber composite. As used herein, the term "fiber composite" or "composite material" refers to multiple fibers within and permeating the resin. The fibers may be coaxially aligned in sheets, layers, or plies, or woven or interwoven in sheets or layers, and / or shredded and randomly dispersed in one or more layers. A single ply typically comprises hundreds or thousands of fiber bundles initially arranged coaxially and parallel to each other, extending through the initially uncured resin. Each fiber bundle comprises multiple fibers. The fibers are made of a high tensile strength material such as carbon. Alternatively, the fibers may be formed from other materials such as glass, graphite, boron, basalt, carrot, Kevlar®, Spectra®, poly(p-phenylene-2,6-benzobisazole) (PBO), hemp, flax, other natural fibers, and combinations thereof. In one set of preferred embodiments, the resin is preferably a thermosetting resin, such as an epoxy or polyester resin. In other sets of preferred embodiments, the resin may be a thermoplastic resin. Composite materials are typically wound around a mandrel and / or similar structure and cured under heat and / or pressure. Upon curing, the resin is configured to flow and fully disperse and extend throughout the fiber matrix. In multilayer or lamellar constructions, fibers may be aligned in different directions relative to the longitudinal axis 22 between layers, and / or in woven or interwoven fabrics.

[0027] refer to Figure 2-5 The illustration shows the production of the frame 12 of the racket 10, which is made of fiber composite material. Figure 2 The diagram illustrates an example arrangement of fiber composite layers forming an uncured fiber composite tube 26 wound or formed around a mandrel 28. The arrangement of the fiber composite layers of the tube 26 can include a wide variety of layers, layer lengths, layer widths, layer shapes, ranges of fiber angle values, other sequences of layers, and combinations thereof, all contemplated within the scope of the invention. The number of layers used to form the frame 12 can range from 2 to 150. In a preferred embodiment, the number of layers used to form the frame 12 or its head portion 14, throat portion 20, and handle portion 40 can be at least 10 layers. In other embodiments, other numbers of layers may be used.

[0028] Mandrel 28 is a body generally shaped to form the inner surface of a molded part and serves as a core, on which uncured fiber composite layers may be wound or applied. In one embodiment, mandrel 28 is an elongated body with a generally rectangular cross-section with rounded corners. In other embodiments, the mandrel may have other cross-sectional shapes. A capsule 30 is placed on mandrel 28 and fitted around the outer surface of mandrel 28. Each layer is wound or formed around capsule 30 and mandrel 28, conforming to the form or shape of capsule 30 and mandrel 28.

[0029] In one embodiment, at least 50% of the layers of the tube 26 forming a laminate or multiple laminate arrangement may be formed of carbon fiber. The laminate may include resin and may have a resin content of at least 120 g / m³. 2 Fiber area weight.

[0030] refer to Figure 2 When the unidirectional laminations of the fiber composite are wound or stacked around the capsule 30 and the mandrel 28, the laminations are no longer arranged as flat sheets. Therefore, the fiber bundles and fibers of the laminations no longer follow or define generally parallel lines. Instead, the fiber bundles and fibers are adjacent to each other and are bent or otherwise shaped such that they follow substantially the same adjacent paths. The fibers remain adjacent to each other, aligned with each other, and follow substantially parallel (or even coaxial) substantially similar paths.

[0031] In one embodiment, the mandrel 28 may include a pull tab to facilitate pulling or removing the mandrel 28 from the tube 26 wound around the capsule 30 and the mandrel 28. Reference Figure 3 and Figure 4 Once the spindle 28 is removed from the capsule 30 and the stack or tube 26, the uncured tube 26 can be gently shaped into the racket frame. The uncured tube 26 includes a first end region 56, a second end region 58, and a middle region 60. The first end region 56 and the second end region 58 are placed side-by-side to form the handle portion 40, and the middle region 60 is used to form the head portion 14 together with the yoke stack 34. The uncured yoke stack 34 may also be formed of a fiber composite material. Figure 4 As shown, tube 26 can be shaped like a racket frame, and yoke stack 34 can be attached to tube 26.

[0032] See Figure 5Uncured tube 26 and uncured yoke stack 34 are positioned within the cavity 36 of racket forming mold 38. The cavity 36 of racket forming mold 38 includes a unique shape that defines the unique shape of the handle portion 16 of frame 12. Supply line 42 may be attached to bladder 30 for supplying air or other gas to bladder, and parts of racket forming mold 38 may be positioned around tube 26 and yoke stack 34. Bladder 30 may be pressurized to a predetermined pressure by air or other gas, and then racket forming mold 38 may be heated to a predetermined temperature in an oven or furnace. Once subjected to heat and pressure, the resin viscosity in the stack of layers in tube 26 and yoke stack 34 decreases, and within cavity 36, resin flows throughout tube 26 and yoke stack 34, producing a more uniform structure, and fibers are positioned to conform to the shape of cavity. After a first predetermined time period, racket forming mold 38 is removed from heat source, allowing tube 26 and yoke stack 34 to cool and cure. After a second predetermined time interval, the racket molding mold 38 is opened, and the racket frame 12 is removed from the mold 38. The frame 12 of the racket 10 can have a weight in the range of 260 gm to 355 gm. In other embodiments, the weight of the racket frame can be outside the range of 180 gm to 370 gm.

[0033] See Figure 1 The head portion 14 is a tubular structure defining a generally elliptical opening 46. The head portion 14 maintains tension in the string mesh forming the string bed 48. The string bed 48 defines a string bed plane 49. The throat region 20 includes a pair of throat tubes 18 extending outward from the head portion 14 and converging at the handle portion 40. The throat region 20 connects the head portion 14 to the handle portion 40. In one embodiment, the pair of throat tubes 18 are integrally formed with the head portion 14 and the handle portion 40. In an alternative preferred embodiment, the throat region 20 may include an elastomeric spacer (not shown) located between the head portion 14 and the handle portion 40. The handle portion 40 extends outward from the throat region 20 along a longitudinal axis 22.

[0034] refer to Figures 6 to 14 The handle assembly 16 is shown in more detail below. The handle assembly 16 includes a handle portion 40, a pad 50, a grip 52, and a base cap 54. The handle assembly 16 is configured to be gripped by one or both hands of an athlete during use. (Reference) Figure 10In one embodiment, the handle portion 40 is formed from a first end region 56 and a second end region 58 of the tube 26 after its curing. During molding and curing, the first end region 56 and the second end region 58 expand to take on the shape of the mold cavity surface and cure together as a single integral component. The first end region 56 and the second end region 58 extend side by side with each other to form a single integral structure. Thus, in such an embodiment, the frame 12 can be formed from a continuous tube of material (e.g., a fiber composite material) that bends in the intermediate region 60 to form the head portion 14. Then, each side of the continuous tube of material can be formed in the throat region 20 toward the converging throat tube 18, and the first end region 56 and the second end region 58 of the continuous tube can be arranged side by side to form the handle portion 40. In this embodiment, the frame 12 is formed as a single integral structure. In other embodiments, the handle portion 40 can be a tubular structure excluding the extension of the throat tube 18. In this embodiment, the handle portion 40 may be a tubular structure separate from the throat portion 20 or the head portion 14 of the frame 12, and attached to the throat portion 20 by using conventional fasteners, molding techniques, bonding techniques, adhesives, or combinations thereof.

[0035] refer to Figures 6 to 8 The handle portion 40 includes a distal region 62, a proximal region 64, and a central region 66 located between the distal region 62 and the proximal region 64 of the handle portion 40. The central region 66 and the proximal region 64 of the handle portion 40 have outer surfaces 68 and 70 that define a first cross-sectional area and a second cross-sectional area, respectively. Figure 7A The first cross-sectional area of ​​the central region 66 with an octagonal shape is shown. Figure 7B The second cross-sectional region 64, which also has an octagonal shape, is shown. Figure 7C A second cross-sectional region 64, which also has an octagonal shape, is shown. Figure 7C In the racket, the tubular frame 12 may be filled with a filler material 86 to improve the sound and feel of the racket. In one embodiment, the filler material 86 may be polyurethane foam with a total weight in the range of 8 to 14 grams. In other embodiments, other materials may be used as filler materials, such as other foams, and the weight of the filler material may also vary.

[0036] Importantly, the proximal region 64 of the handle portion 40 is enlarged such that the second cross-sectional area defined by the outer surface 70 of the proximal region 64 is larger than the first cross-sectional area defined by the outer surface 68 of the central region 66. Each of the distal region 62, the proximal region 64, and the central region 66 has an outer surface defining a polygonal cross-sectional shape. In other embodiments, other cross-sectional shapes, such as elliptical, circular, and irregular shapes, may be used. The proximal region 64 of the handle portion 40 includes a proximal end 72 and a sidewall 74, the sidewall 74 including a first length. l 1 Second length l 2 The first length of the sidewall 74 l 1 A uniform polygonal cross-sectional area can be defined extending from the proximal end 72 of the proximal region 64 in a direction toward the head portion 14. In one embodiment, the first length l 1 It can be at least 10 mm. In other embodiments, the first length... l 1 It can be in the range of 10 to 50 mm. In other embodiments, the first length... l 1 It can be within the range of 10 to 30 mm. Figures 11 to 13 The first length is shown l 1 Three examples of different lengths that increase or decrease the length and size of the proximal region 64 of the handle portion 40. The second length of the sidewall 74. l 2 Having from the first length l 1 The cross-sectional area 66 changes in the central region of the handle portion 40. Second length. l 2 It can be at least 10 mm. The second length of the central region 66 and the proximal region 64. l 2 The distal region 62 may define a recess 80. The recess 80 may have a depth d of at least 2 mm, defined by the outer surface 76 of the central region 66 and the outer surface of the proximal region 64. In other embodiments, the depth d of the recess 80 may be in the range of 1 to 10 mm. The recess 80 may extend uniformly inward into the side portion of the polygonal central region 66, such that the second cross-sectional area of ​​the proximal region 64 is larger than the first cross-sectional area of ​​the central region 66.

[0037] refer to Figure 14In another embodiment, the proximal region 64 may form a continuously variable cross-sectional shape from the proximal end 72 of the handle portion 40 to the central region 64. In this embodiment, the handle portion need not have two different lengths defined by a constant and a variable cross-sectional region. l 1 and l 2 And having a complete length that defines a continuously variable cross-sectional shape. l 3 .exist Figure 14 In one embodiment, the cross-sectional shape is polygonal (e.g., octagonal), and the dimensions decrease from the proximal end 72 to the central region 64. In other embodiments, the cross-sectional region may take other shapes and may vary in size in other ways, such as by different amounts of reduction over a particular sub-length, being generally convex, generally concave, or variable. In each case, the proximal region 64 is enlarged to allow the bottom cover 54 to be directly attached to or attached to the proximal region 64.

[0038] refer to Figure 10 The pad 50 is coupled to and extends longitudinally over the central region 66 of the handle portion 40, but not over the proximal region 64 of the handle portion 40. For the purposes of this disclosure, the term "coupled" means direct or indirect connection. In one embodiment, the pad 50 is located on the central region 66 of the handle portion 40. In other embodiments, the pad 50 may also be positioned over a portion of the proximal region 62 and the distal region 64 of the handle portion 40. In each case, the pad 50 is formed or sized to match the contour of the central region 66 and any portion of the proximal region 62 and / or the distal region 64 over which it may extend. In one embodiment, the pad 50 may be overmolded onto the handle portion 40. In other embodiments, the pad 50 may be applied to the handle portion by other means, such as adhesives, one or more fasteners, interference fits, and combinations thereof. The pad 50 preferably has a polygonal cross-sectional shape, such as an octagonal shape formed by eight external longitudinally extending surfaces interconnected along eight longitudinally extending gripping edges. In an alternative preferred embodiment, the pad 50 may have alternative cross-sectional shapes, such as other polygonal, elliptical, circular, and irregular shapes. The pad 50 is made of a strong, lightweight, and durable material such as rigid polyurethane foam. Alternatively, the pad 50 may be formed of other materials, such as other structural urethane foams, other structural foams, plastic materials, or wood. In other embodiments, the pad 50 may be formed of an elastic material capable of stretching over the handle portion 40. In a preferred embodiment, the length of the pad 50 is between 4.0 and 9.5 inches; and, in a particularly preferred embodiment, the pad 50 has a length of approximately 6.0 to 8.0 inches.

[0039] The bottom cover 54 is securely attached to the proximal region 64 of the handle portion 40 and covers at least a portion of the outer surface 70 of the proximal end 72 and the proximal region 64. The bottom cover 54 is formed of a lightweight, durable material such as plastic. Alternatively, the bottom cover may be formed of other materials such as nylon, wood, thermosetting materials, thermoplastic materials, and combinations thereof. The bottom cover 54 includes a proximal wall 84 and a peripheral wall 82, the peripheral wall 82 extending from the proximal wall 84 and surrounding the proximal region 64 of the handle portion 40, without extending over the pad 50. In one embodiment, the peripheral wall 82 has a first length in the proximal region 64. l 1 Extending upwards. In one embodiment, the bottom cap 54 is directly connected to the proximal region 64 of the handle portion 40. In other embodiments, the bottom cap 54 may be securely fixed to the proximal region 64 by one or more fastening mechanisms, such as adhesives, pins, screws, nails, rivets, U-bolts, interference fits, and combinations thereof. In one embodiment, the bottom cap 54 is fixed to the proximal region 64 by one or more U-bolts. The peripheral wall 82 has a length extending from the proximal wall 84 and surrounding the proximal region 64 of the handle portion 40, wherein less than half of the length of the proximal wall extends over the pad 50. In one embodiment, the bottom cap 54 is fixed to the proximal region 64 of the handle portion 40 such that the peripheral wall 82 extends over the proximal region 64, and less than half of the length of the peripheral wall 82 may also extend over a portion of the pad 50. The length of the peripheral wall 82 is measured with reference to the longitudinal axis 22 of the racket 10 and extends from the proximal wall 84 to the distal edge of the peripheral wall 82 of the bottom cap 54. In other embodiments, less than a quarter of the length of the peripheral wall 82 may extend over the pad 50. In another embodiment, the peripheral wall 82 extends only over the proximal region 64 of the handle portion 40, and not over the pad 50.

[0040] The enlarged proximal region 64 of the handle portion 40 allows the bottom cap 54 to be connected to the proximal region 64 without the need for the peripheral wall 82 extending onto the pad 50. The proximal region 64, formed of a fiber composite material, is stronger and more durable than the pad 50. Therefore, according to the above embodiment, the direct connection between the bottom cap 54 and the proximal region 64 significantly increases the durability of both the bottom cap 54 and the racket 10. On conventional rackets, the bottom cap is typically connected to a less durable pad that usually extends entirely to the proximal end of the racket. Compared to the proximal region 64 of the handle portion 40, the pad is more fragile and more prone to cracking or breaking. When the racket is dropped, the bottom cap impacts the ground or other surfaces. Furthermore, when serving or making other tennis shots, the player frequently grips the bottom cap. Therefore, the bottom cap receives a significant load during use. Over time, repeated use can weaken or even cause the connection between the bottom cap and the pad to fail, leading to the bottom cap loosening, shifting, and / or separating from the racket. This embodiment, by directly connecting the bottom cover 54 to the enlarged surrounding area 64 of the handle portion 40, significantly strengthens the connection between the bottom cover 54 and the handle portion 40, thereby significantly increasing the overall reliability and durability of the racket 10.

[0041] A grip 52 is applied to the outer surface of the sleeve 50, a portion of the proximal region 64, and a portion of the peripheral wall 82 of the bottom cover 54. In one embodiment, the grip 52 may comprise adhesive tape. Alternatively, the grip 52 may be attached to the sleeve 50 and the proximal region 64 by other means, such as conventional fluid adhesives, thermal bonding, or mechanical bonding. The grip 52 is an elongated strip of a soft, durable material. The grip 52 may be made of leather, synthetic leather, rubber, other thermosetting materials, thermoplastic materials, or combinations thereof. The grip 52 is typically spirally or coiled around the outer surface of the sleeve 50. In an alternative preferred embodiment, the grip 28 may be a tubular member slidably attached to the outer surface of the sleeve 50 and the proximal region 64.

[0042] refer to Figures 15 to 17Wilson Sporting Goods Co. conducted racket torsional stability tests using a racket torsional stability test assembly 140. The racket torsional stability test includes a frame 142 with a first test clamp 144 and a second test clamp 146 for mounting the racket 10 to a first position 148 and a second position 150, respectively. The term "racket torsional stability test" refers to a test that meets the following description. The string bed is removed from the head portion 14 of the frame 12, and the grip 52 and bottom cap 54 are removed from the handle assembly 16 of the racket 10. The racket 10 is positioned in the first test clamp 144 and the second test clamp 146, with the longitudinal axis 22 of the racket 10 and the string bed plane 49 parallel to the ground. A first test clamp 144 securely holds the handle assembly 16 (without a grip and bottom cap) and is pivotally mounted to a frame 142 to allow the first clamp 144 (and the handle assembly 16 clamped to it) to pivot or rotate about the longitudinal axis 22 of the racket 10. The first test clamp 144 also includes an arm 152 that projects or extends radially from the first test clamp 144 and the longitudinal axis 16. The arm 152 includes one or more indexes 154 for receiving a first weight 156 at a predetermined distance from the longitudinal axis 16. In one embodiment, the first weight is 6.9 kg, and the predetermined distance from the longitudinal axis 22 is 40 cm. A second test clamp 146 securely holds the head portion 18 of the racket 10 in a fixed position, wherein the string bed plane 49 of the racket 10 is positioned parallel to the ground. A digital inclinometer 160, such as the Wixey™ Digital Goniometer WR300, Type 2, manufactured by BarryWixey Development, Sanibel, Florida, is removably mounted on the second test fixture 144 at the longitudinal axis 22. A first weight 156 is applied to the arm 152 at a predetermined distance of 40 cm from the axis 22. The first weight 156 applied to the arm 152 applies a torsional load to the handle assembly 16 of the racket 10, causing the first test fixture 144 (and the handle assembly 16) to rotate relative to the frame 142 and about the longitudinal axis 22. Reference Figure 17 The digital inclinometer 160 is zeroed, and the first weight 156 is removed. The measuring arm 152 and handle assembly 16 deflect or move relative to the longitudinal axis 22. Although Figure 15-17 The racket shown is unstrung, but racket torsional stability testing can also be performed on strung rackets. For the purposes of the claimed invention, the racket tested under racket torsional stability testing is unstrung.

[0043] The racket torsional stability test was conducted on six rackets. The first group of three rackets were three existing Wilson® Blade® v7.0 rackets, which did not include the enlarged proximal region 64 of the handle portion 40. Instead, in the first group of three Wilson® Blade® v7.0 rackets, the cross-sectional area of ​​the handle portion 40 was constant from the central region 66 to the proximal end 72. Furthermore, the pad 50 also extended to the proximal end 72 of the handle portion 40, and the bottom cap 54 was attached to the pad 50 in a conventional manner. The second group of three rackets were prototype rackets, identical to the first group of three Wilson® Blade® v7.0 rackets, except that the handle portion 40 was formed according to an embodiment of the invention, and the proximal region 64 of the handle portion 40 was enlarged, as shown in the figure. Figure 9 and Figure 10 As shown in Table 1 below, the results of the racket lateral bending test for the three rackets in the first and second groups are listed. All rackets were tested without being strung.

[0044] Table 1. Measurement of racket torsional stability .

[0045] The racket torsional stability test results, comparing the first group of three existing rackets with the second group of three prototype rackets having an enlarged proximal region 64 of the handle portion 40, show that the racket's torsional stability is significantly improved, or the racket's angular deflection is reduced, during the test. The three prototype rackets with the enlarged proximal region 64 of the handle portion 40 exhibited a torsional angular deflection value that was at least 13.3% lower or better than the corresponding existing rackets. The prototype rackets exhibited an angular deflection value of no more than 4.7 degrees in the racket torsional stability test. Therefore, the racket formed according to the present invention provides a more durable bottom cap connection for the handle assembly and also provides significantly improved torsional stability.

[0046] While preferred embodiments of the invention have been described and illustrated, those skilled in the art will envision many deviations from the preferred embodiments. Therefore, the invention is not limited to the foregoing description, but only to the scope and spirit of the appended claims.

Claims

1. A sports racket, comprising: An integral tubular frame formed of fiber composite material includes a first end region, a second end region, and a middle region. The first end region and the second end region extend side by side to form part of the handle of the racket. The middle region forms part of the head of the racket. The first end region and the second end region of the integral tubular frame include a distal region, a proximal region, and a central region located between the distal region and the proximal region of the integral tubular frame. The central region and the proximal region of the integral tubular frame have a first outer surface and a second outer surface defining a first cross-sectional area and a second cross-sectional area, respectively. The second cross-sectional area is larger than the first cross-sectional area. A sleeve, the sleeve being coupled to and extending longitudinally over the central region of the integral tubular frame, but not extending over the proximal region of the integral tubular frame; and A bottom cover, which is securely fixed to the proximal region of the first end region and the second end region of the integral tubular frame, the bottom cover including a proximal end wall and a peripheral wall, the peripheral wall being directly connected to the second outer surface and having a length extending from the proximal end wall and surrounding the proximal region of the integral tubular frame, and less than half the length of the peripheral wall extending over the pad.

2. The sports racket according to claim 1, wherein, The second cross-sectional area has a polygonal shape.

3. The sports racket according to claim 1 further includes a grip disposed on the pad.

4. The sports racket according to claim 1, wherein, The middle region of the frame also forms a pair of throat tubes between the head portion and the handle portion.

5. The sports racket according to claim 1, wherein, The bottom cover is directly attached to the proximal regions of the first and second end regions of the integral tubular frame by an adhesive.

6. The sports racket according to claim 1, wherein, The bottom cover is connected to the proximal regions of the first and second end regions of the integral tubular frame by a fastening mechanism selected from the group consisting of adhesives, U-shaped nails, nails, rivets, pins, screws, interference fits and combinations thereof.

7. The sports racket according to claim 2, wherein, The proximal region includes a sidewall having the second outer surface and forming the second cross-sectional region.

8. The sports racket of claim 7, wherein the first end region and the second end region of the integral tubular frame include a proximal end, and wherein the sidewall has a first length defining a constant polygonal cross-sectional area extending from the proximal end of the first end region and the second end region of the integral tubular frame in a direction toward the head portion.

9. The sports racket according to claim 8, wherein, The first length of the sidewall, measured from the proximal end toward the head portion, is at least 10 millimeters.

10. The sports racket of claim 8, wherein the first length of the sidewall, measured from the proximal end toward the head portion, is in the range of 10 to 50 mm.

11. The sports racket of claim 8, wherein the sidewall further defines a second length having a cross-sectional area that varies from the first length to the central region of the first end region and the second end region of the integral tubular frame.

12. The sports racket of claim 11, wherein the second length of the sidewall is at least 10 mm.

13. The sports racket according to claim 11, wherein, The second length defines a depth of at least 5 millimeters.

14. The sports racket according to claim 1, wherein, The proximal wall of the bottom cover does not extend over the gasket.

15. The sports racket according to claim 1, wherein, The entire surrounding wall of the bottom cover does not extend over the gasket.

16. The sports racket according to claim 1, wherein, The surrounding wall of the bottom cover abuts against the second outer surface.

17. The sports racket according to claim 1, wherein, The distal regions of the first and second end regions of the integral tubular frame have a third outer surface that defines a third cross-sectional area that is larger than the first cross-sectional area, such that the pad is longitudinally captured between the proximal and distal regions along the central region.

18. A racket extending along a longitudinal axis, the racket comprising: An integral tubular frame formed of fiber composite material, the integral tubular frame including a first end region and a second end region and a middle region, the first end region and the second end region extending side by side at a handle, and the middle region forming part of a head portion, the handle portion including a distal region, a proximal region and a central region located between the distal region and the proximal region of the handle portion, the central region and the proximal region of the handle portion having outer surfaces defining a first cross-sectional area and a second cross-sectional area, the second cross-sectional area being larger than the first cross-sectional area, the proximal region including a proximal end and a sidewall forming a polygonal cross-sectional area, the sidewall having a first side portion and a second side portion, the first side portion extending from the proximal end and having a length of at least 10 mm, the first side portion defining a consistent polygonal cross-sectional area along its length, the second side portion defining a cross-sectional area varying from the first side portion to the central region of the handle portion, the second side portion having a length of at least 10 mm; A sleeve, the sleeve being coupled to the central region of the handle portion and extending longitudinally over the central region, but not extending over the proximal region of the handle portion; and A bottom cover, securely fixed to the proximal region of the handle portion, the bottom cover including a proximal wall and a peripheral wall, the peripheral wall having a length extending from the proximal wall and surrounding the proximal region of the handle portion, and less than half the length of the peripheral wall extending over the pad. The proximal wall of the bottom cover does not extend over the sleeve.

19. The sports racket according to claim 18, wherein, The entire surrounding wall of the bottom cover does not extend over the gasket.

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