FIELD OF THE INVENTION

[0001] The present invention generally relates to sports balls. In particular, the present invention relates to sports balls structured to have a center mass that affects the rebound of the sports ball.

BACKGROUND OF THE INVENTION

[0002] Sport balls may include, among others, golf balls, baseballs, basket balls and soccer balls. Two of the important properties of these balls are rebound and coefficient of restitution. Rebound is the ratio of how high ball bounces as compared to the height from which it was dropped. Coefficient of restitution is the ratio of the velocity of a ball as it returns, upward velocity, to the velocity of the ball as it is dropped, downward velocity. Both properties relate to how the ball bounces and the properties are directly related. That is, as rebound increases, coefficient of restitution increases. Many attempts have been made to develop balls with improved endurance and performance. Golf ball design progressed from leather balls to rubber band wound balls with synthetic covers to complex exterior surface designs (such as a myriad of dimple design), all with the objective to increase the flight of the ball. The soccer ball design, while changing construction materials, has strict guideline of the rebound as does the baseball, croquet ball and basketball. These balls all have rebound specifications greater that 25%. The description of rebound herein is expressed in percentages, with the understanding that the percentage represents the percentage of the drop height attained by the ball upon rebounding after being dropped from a drop height and permitted to bounce off of a flat ground surface under the effect of gravity only.

[0003] U.S. Published Patent Application US 2008/0242458 describes a ball that uses a loose filling to deaden the bounce of the ball. This application requires loosely placing a material inside the bladder of a pneumatic ball. The present invention differs significantly from the ball described in 2008/0242458.

[0004] The primary methods to control the rebound of a sports ball have been related to material and pressure, among others. For example, the use of different materials can have a significant effect on rebound. The effect of air pressure on the rebound of a ball is described in U.S. Patent 4,098,048. As pressure within the ball is increased, the rebound increases. These methods along with construction have been used to maximize the rebound of a sports ball and to ensure that the rebound is within the specified limits for the sporting activity. A comparison of the rebound of various sports balls is shown in the table below:

[0005] Another lesser known prior art sports ball is the Futsal. This ball is manufactured to reduce bounce by filling the bladder with foam or fiber filler. The rebound of the Futsal is 25 to 35%.

[0006] Although not an exhaustive look at sports balls, it can be seen that rebounds greater than 25% are expected. The present invention will allow sports balls to be designed with rebounds typically from 5 to 25%. SUMMARY OF THE INVENTION

[0007] A first embodiment of this invention provides a sports ball comprising: a bladder defining the general shape of the sports ball and defining an interior of the sports ball, and a mass held inside of said interior of the sports ball and retained in a rest position relative to said bladder such that, upon impact between the sports ball and another structure, the position of said mass relative to said bladder changes and thereby dampens and affects the rebound of the sports ball.

[0008] A second embodiment provides a sports ball as in the first embodiment, wherein said mass has a symmetrical shape with a consistent, symmetric weight distribution. [0009] A third embodiment provides a sports ball as in either of the first or second embodiment, wherein said mass has an asymmetrical shape with a variable, asymmetric weight distribution.

[0010] A fourth embodiment provides a sports ball as in any of the first through third embodiments, wherein said mass is from 2% or more to 30% or less of the total weight of the ball.

[0011] A fifth embodiment provides a sports ball as in any of the first through fourth embodiments, wherein said mass occupies a rest position wherein said mass is distanced from the bladder.

[0012] A sixth embodiment provides a sports ball as in any of the first through fifth embodiments, wherein the sports ball has a center and said mass occupies a rest position wherein the mass is positioned within 0 to 5% of said center.

[0013] A seventh embodiment provides a sports ball as in any of the first through sixth embodiments, wherein said mass is positioned to overlap with said center of the ball.

[0014] An eighth embodiment provides a sports ball as in any of the first through seventh embodiments, wherein said mass is positioned to place the center of the mass proximate the center of the ball.

[0015] A ninth embodiment provides a sports ball as in any of the first through eighth embodiments, wherein said mass is hollow and retains a fill material to provide weight and affect rebound of the sports ball.

[0016] A tenth embodiment provides a sports ball as in any of the first through ninth embodiments, wherein said bladder is an elastic material selected from polyisoprene, polybutadiene, polyisobutylene and blends of thereof.

[0017] A eleventh embodiment provides a sports ball as in any of the first through tenth embodiments, wherein said bladder is a thermoplastic material selected from polyethylene, polypropylene, polyvinylchloride (PVC), polyurethane and mixtures thereof.

[0018] A twelfth embodiment provides a sports ball as in any of the first through eleventh embodiments, said mass is suspended inside said bladder by a plurality of supports attached to said bladder and said mass, said supports having elastic properties with sufficient strength to suspend said mass, yet low enough strength to flex when said bladder decelerates allowing said mass to continue to travel.

[0019] A thirteenth embodiment provides a sports ball as in any of the first through twelfth embodiments, where said plurality of supports includes at least 3 supports.

[0020] A fourteenth embodiment provides a sports ball as in any of the first through thirteenth embodiments, wherein said plurality of supports are positioned symmetrically within the ball and each of said plurality of supports provide identical resistance to movement of the mass.

[0021] A fifteenth embodiment provides a sports ball as in any of the first through fourteenth embodiments, wherein said bladder is an elastic material having a tensile strength of 10 MPa or greater.

[0022] A sixteenth embodiment provides a sports ball as in any of the first through fifteenth embodiments, wherein said bladder is an elastic material having a stress at 300% elongation between 3 and 15 MPa.

[0023] A seventeenth embodiment provides a sports ball as in any of the first through sixteenth embodiments, wherein each of said plurality of supports has an ultimate elongation of from 50% or more to 500% or less.

[0024] A eighteenth embodiment provides a sports ball as in any of the first through seventeenth embodiments, where the stress required to elongate each of said plurality of supports to 300% is from 2 MPa or more to 10 MPa or less.

[0025] A nineteenth embodiment provides a sports ball as in any of the first through eighteenth embodiments, wherein said bladder is pressurized to provide the general shape of the sports ball.

[0026] A twentieth embodiment provides a sports ball as in any of the first through nineteenth embodiments, wherein said mass is held by a foam that supports said mass by extending between said bladder and said mass so as to provide support for the mass.

[0027] A twenty-first embodiment provides a sports ball as in any of the first through twentieth embodiments, wherein said foam has sufficient strength to suspend said mass, yet low enough strength to flex when said bladder decelerates allowing said mass to continue to travel. [0028] A twenty-second embodiment provides a sports ball as in any of the first through twenty-first embodiments, wherein the foam has a density of 0.02 or more to 0.5 or less g/cc.

[0029] A twenty-third embodiment provides a sports ball as in any of the first through twenty-second embodiments, wherein the stress required to compress the ball 20% is from 0.01 or more to 0.25 or less MPa.

[0030] A twenty-fourth embodiment provides a sports ball as in any of the first through twenty-third embodiments, wherein said bladder serves as the exterior of the sports ball.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Fig. 1 is a general schematic of the dropping of a traditional sports ball to a base line and the rebound thereof, wherein:

[0032] Fig. 1A shows the ball at rest prior to dropping,

[0033] Fig. IB shows the ball after release and at the moment of impact with the baseline,

[0034] Fig. 1C shows the ball 10 compressed upon impact with the baseline,

[0035] Fig. ID shows the ball upon initial rebound, and

[0036] Fig. IE shows the maximum rebound of the ball.

[0037] Fig. 2 provides comparisons of a traditional sports ball and sports balls in accordance with this invention, wherein:

[0038] Fig. 2A is a traditional ball,

[0039] Fig. 2B is a first embodiment of a sports ball in accordance with this invention, shown with a portion of a bladder removed to view internal structures, and

[0040] Fig. 2C shows a second embodiment of a sports ball in accordance with this invention, shown sectioned to show internal structures.

[0041] Fig. 3 is a general schematic of the dropping of a traditional sports ball to a base line and the rebound thereof, wherein:

[0042] Fig. 3A shows the ball at rest prior to dropping,

[0043] Fig. 3B shows the ball after release and at the moment of impact with the baseline,

[0044] Fig. 3C shows the ball 10 compressed upon impact with the baseline, [0045] Fig. 3D shows the ball upon initial rebound, and

[0046] Fig. 3E shows the maximum rebound of the ball.

[0047] Fig. 4 shows an exemplary embodiment of a sports ball of this invention employing a cover and an additional layer.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0048] The present invention applies to the physics of reducing the rebound of a sports ball, where the rebound is not controlled by material or pneumatic pressure but by the unique construction of the ball. Fig. 1 illustrates the rebound of a conventional sports ball 10. Fig. 1A shows the ball 10 at rest at an initial height prior to dropping. Fig. IB is the ball 10 after being released and at the moment of impact with the base line. Fig. 1C represents the ball 10 after impact, and shows compression of the ball 10, which loads potential energy that results in rebound as shown in Figs. ID and IE. Fig IE represents the ball at its maximum rebound.

[0049] Fig. 2 compares the traditional ball to various embodiments of the present invention. Fig. 2A shows a traditional ball 10 defined by a bladder 12 that also serves as the exterior cover of the ball 10. This ball may be either pneumatic or solid. Solid balls are filled with a variety of materials that have either high densities (generally greater than 1 gram per cc, as in the golf ball) or have low densities (generally less than 1 g per cc, as in foam filled balls). The bladder 12 may be integral to a solid filled ball or a separate component in a pneumatic ball.

[0050] Fig. 2B shows a first embodiment of a ball 110 in accordance with the present invention. The ball 110 is a pneumatic ball where a bladder 112 is supported by pressurized air and defines the shape of the ball 110. A mass 114 is supported inside the bladder 112 by a plurality of supports 116, which are attached to the bladder 112 and the mass 114. Supports 116 are made of an elastic material with sufficient strength to suspend the mass 114, yet low enough strength to flex when the bladder 112 decelerates allowing the mass 114 to continue to travel. The bladder 112 forms a desired sports ball shape upon expansion under the influence of the pressurized air therein. In some embodiments, the bladder serves as the exterior of the sports ball. In other embodiments, such as that shown in Fig. 4, a cover 118 is employed to provide the exterior. Additional layers such as layer 117 could be employed, but the broad concept is to provide a bladder with a mass 114 held therein by supports 116. The bladder 112 can provide the exterior of the ball or can be covered with one or more layers such as layer 117 and/or cover 118. In some embodiments, the sports ball is formed by the bladder 112, without additional layers, such that the bladder 112 provides the appearance of a particular type of traditional sports ball.

[0051] In some embodiments, the bladder 112 is made of an elastic material. In some embodiments, the bladder 112 is made of an elastic material selected from polyisoprene, polybutadiene, polyisobutylene and blends of these materials among others. In some embodiments, the bladder 112 is made of a thermoplastic material. In some embodiments, the bladder 112 is made of a thermoplastic material selected from polyethylene, polypropylene, polyvinylchloride (PVC), polyurethane and mixtures of the foregoing.

[0052] In some embodiments, the bladder 112 is made of a polyisoprene compounded with a non-black filler such as silica or calcium carbonate. This embodiment may further include the necessary chemicals to facilitate crosslinking including but not limited to zinc oxide, stearic acid, sulfur and an appropriate chemical to accelerate crosslinking such as a mercaptobenzothiazole or sulfonamide. Coloring agents such as titanium oxide may be added to achieve a bladder providing a white exterior. In some embodiments, the bladder 112 is made of a thermoplastic material such as PVC compounded with plasticizers such as diisooctyl phthalate to obtain the desired properties.

[0053] In some embodiments, the material of bladder 112 is an elastic material having a tensile strength of 10 MPa or greater, in other embodiments, 12 MPa or greater, and in other embodiments, 15 MPa or greater. In some embodiments, the material of bladder 112 is an elastic material having a stress at 300% elongation between 3 and 15 MPa, in other embodiments, between 5 and 12 MPa, and, in other embodiments, between 5 and 10 MPa.

[0054] Aspects of the mass 114 can affect the rebound of the ball 110. These include its weight and its geometry. In some embodiments, the weight of the mass 114 is from 2% or more to 30% or less of the total weight of the ball 110. In some embodiments, the weight of the mass 114 is from 2% or more to 20% or less, in other embodiments, from 2% or more to 15% or less, in other embodiments, from 2% or more to 10% or less, in other embodiments, from 5% or more to 20% or less, in other embodiments, from 5% or more to 15% or less, in other embodiments, from 10% or more to 15% or less of the total weight of the ball 110. The mass is generally kept as small as possible to avoid adding unnecessary weight to the ball.

[0055] In this embodiment, the amount the rebound is retarded is dependent on the dynamic properties of the supports 116 A fully rigid material, that is a material with ultimate elongation less than 10% and tensile strength greater than 30 MPa would have little effect on retarding the rebound. In some embodiments, the supports 116 have ultimate elongations of from 50% or more to 500% or less. In some embodiments, the stress required to elongate the support to 300% is from 2 MPa or more to 10 MPa or less. In other embodiments, the stress required to elongate the support to 300% is from 2 MPa or more to 8 MPa or less, in other embodiments, from 2 MPa or more to 5 MPa or less, in other embodiments, from 2 MPa or more to 3.5 MPa or less, in other embodiments, from 3.5 MPa or more to 5 MPa or less, and, in other embodiments, from 5 or more to 10 MPa or less. Lower stresses at 300% retard the rebound more that higher stresses.

[0056] In some embodiments, the mass 114 is attached to the bladder by at least two supports. In some embodiments the mass 114 is attached to the bladder by at least three supports, in other embodiments, at least 4 supports, in other embodiments, at least 6 supports, in other embodiments, at least 8 supports In some embodiments, the supports are positioned symmetrically within the ball so that the ball remains centered when at rest. In some embodiments, the supports provide identical resistance to movement of the mass, thus helping to ensure a consistent reaction by the ball to an incoming force (such as being kicked or thrown or dribbled etc.) . In some embodiments the supports are positioned symmetrically within the ball and the supports provide identical resistance to movement of the mass. In some embodiments, the mass 114 is attached to the bladder by two or more supports so as to occupy a rest position wherein the mass is distanced from the wall or walls of the ball 110. In some embodiments, the mass 114 is attached to the bladder by two or more supports so as to occupy a rest position wherein the mass is positioned within 0 to 5% of the center of the ball 110. In general the sports balls considered by this invention are an ellipsoid with the spherical ball being a subset of the ellipsoid. For the spherical ball, the center is the intersection of the radius. For an ellipsoid the center is the intersection of the major and minor axis. In some embodiments, the mass is positioned to at least overlap with the center of the ball. In some embodiments, the mass is positioned to place the center of the mass 114 proximate the center of the ball 110.

[0057] It will be appreciated that the shape of the mass and its weight distribution - be it of symmetrical shape with a consistent, symmetric weight distribution or of an asymmetrical shape with a variable, asymmetric weight distribution - affect the rebound characteristics of the ball 110, and do so in accordance with the positioning of the mass 114 relative to the center of the ball 110. In some embodiments, the mass 114 is of symmetric shape. In some embodiments, the mass 114 is spherical and has a symmetric weight distribution. In some embodiments, the mass 114 is spherical and the bladder 112 is spherical, and the mass 114 is attached to the bladder 112 by two or more supports 116 so as to place the center of the mass 114 at proximate the center of the ball 110. In some embodiments, the mass 114 is spherical and the bladder 112 is spherical, and the mass 114 is attached to the bladder 112 by two or more supports 116 so as to place the center of the mass 114 at proximate the center of gravity of the bladder 112.

[0058] In some embodiments, the mass is solid. In other embodiments, the mass is hollow. With reference to Fig. 4, in other embodiments, the mass 114 is hollow and retains a fill material 115 to provide weight and affect rebound. In some embodiments, the fill material 115 is selected from the group consisting off lead beads, steel beads or other metal alloys. In other embodiments the fill material is selected from the group consisting of polyester, acetate, cellulose, cotton or other fibers. Selection of these materials can be made so that the rebound of the ball can be in the 5 to 25% range. It will be appreciated that this aspect of the mass 114 is separate and distinct from any use of layers or a cover such as layer 117 or cover 118, and these concepts are shown together in Fig. 4 just for efficiency.

[0059] In a specific embodiment, the sports ball is a soccer ball having a bladder 112 made of polyisobutylene, a layer 117 made of fabric and a cover 118 formed of PVC and designed to resemble a soccer ball. The bladder is pressurized to form the general shape of the soccer ball. At least four supports attach the mass to the bladder so as to place the center of the mass proximate the center of the sports ball. The supports are made from polyisoprene rubber (natural rubber) and compounded with filler, plasticizers and ingredients to facilitate vulcanization. The ultimate elongation of the supports is greater than 500% and the stress at 300% elongation is 2.1 MPa.

[0060] In some embodiments, the ball 110 of Fig. 2B is pressurized to a pressure of from 0.3 bar or more to 1.2 bar or less (30,000 Pa to 120,000 Pa). In other embodiments, the ball 110 is pressurized to a pressure of from 0.4 bar or more to 1.0 bar or less (40,000 Pa to 100,000 Pa), in other embodiments, from 0.5 bar or more to 0.9 bar or less (50,000 Pa to 90,000 Pa), and, in other embodiments, from 0.6 bar or more to 0.8 bar or less (60,000 Pa to 80,000 Pa).

[0061] A second embodiment of a ball of this invention is shown in Fig. 2C and designated by the numeral 210. Ball 210 is solid, with a bladder 212 being supported by foam 220. A mass 214 is supported inside the bladder by the foam 220. The foam 220 has sufficient strength to suspend the mass 214 yet of low enough strength to flex when the bladder 212 decelerates allowing the mass 214 to continue to travel. In some embodiments, the foam 220 is made of an elastic material with sufficient strength to suspend the mass 214 yet of low enough strength to flex when the bladder 212 decelerates allowing the mass 214 to continue to travel. In some embodiments, the bladder serves as the exterior of the sports ball. In other embodiments, a cover is employed to provide the exterior. Additional layers could be employed, but the broad concept is to provide a bladder with a mass held therein by foam. The bladder 212 can provide the exterior of the ball or can be covered with one or more layers. In some embodiments, the sports ball is formed by the bladder 212, without additional layers, such that the bladder 212 provides the appearance of a particular type of traditional sports ball. This concept is addressed in Fig. 4 and readily applicable to this embodiment.

[0062] In some embodiments, the bladder 212 is made of an elastic material. In some embodiments, the bladder 212 is made of an elastic material selected from polyisoprene, polybutadiene, polyisobutylene and blends of these materials among others. In some embodiments, the bladder 212 is made of a thermoplastic material. In some embodiments, the bladder 212 is made of a thermoplastic material selected from polyethylene, polypropylene, polyvinyl chloride (PVC), polyurethane and mixtures of the foregoing.

[0063] In some embodiments, the bladder 212 is made of a polyisoprene compounded with a non-black filler such as silica or calcium carbonate. This embodiment may further include the necessary chemicals to facilitate crosslinking including but not limited to zinc ocide, stearic acid, sulfur and an appropriate chemical to accelerate crosslinking such as a mercaptobenzothiazole or sulfonamide. Coloring agents such as titanium oxide may be added to achieve a bladder providing a white exterior. In some embodiments, the bladder 212 is made of a thermoplastic material such as PVC compounded with plasticizers such as diisooctyl phthalate to obtain the desired properties.

[0064] In some embodiments, the foam 220 has a density of 0.02 or more to 0.5 or less g/cc. In some embodiments, the foam 220 has a density of 0.02 or more to 0.05 or less, in some embodiments, from 0.05 or more to 0.1 or less, and in other embodiments, from 0.1 or more to 0.5 or less g/cc. In addition to considering the foam density selection of the compression deflection properties are considered critical in some embodiments. Thus, in some embodiments the stress required to compress the ball 20% is from 0.01 or more to 0.25 or less MPa. In other embodiments, the stress required to compress the ball 20% is from 0.01 or more to 0.04 or less MPa, in other embodiments, from 0.04 or more to 0.1 or less MPa, and, in other embodiments, from 0.1 or more to 0.25 or less MPa.

[0065] In some embodiments, the foam 220 is polyether urethane foam, polyester urethane foam, silicone rubber foam or others material selected to give the required properties of density and compression. The amount that the rebound is retarded in the foam ball embodiment exemplified in Fig. 2C is dependent on the dynamic properties of the foam 220. Materials requiring lower stresses to compress the ball 20%, i.e., 0.01 to 0.04 MPa, result in lower rebound than materials requiring higher stresses to compress the ball 20%, i.e., 0.1 to 0.25 MPa.

[0066] Aspects of the mass 214 can affect the rebound of the ball 210. These include its weight and its geometry. In some embodiments, the weight of the mass 214 is from 2% or more to 30% or less of the total weight of the ball 210. In some embodiments, the weight of the mass 214 is from 2% or more to 20% or less, in other embodiments, from 2% or more to 15% or less, in other embodiments, from 2% or more to 10% or less, in other embodiments, from 5% or more to 20% or less, in other embodiments, from 5% or more to 15% or less, in other embodiments, from 10% or more to 15% or less of the total weight of the ball 210.

[0067] The weight of the mass and the geometry of the mass also affect the rebound of the ball 210. In some embodiments, the mass 214 is held by the foam 220 to occupy a rest position wherein the mass 214 is distanced from the wall or walls of the ball 210. In some embodiments, the mass 214 is held by the foam 220 so as to occupy a rest position wherein the mass 214 is positioned within 5% of the center of the ball 210. In general the sports balls considered by this invention are an ellipsoid with the spherical ball being a subset of the ellipsoid. For the spherical ball the center is the intersection of the radius. For an ellipsoid the center is the intersection of the major and minor axis. In some embodiments, the mass is positioned to at least overlap with the center of the ball. In some embodiments, the mass is positioned to place the center of the mass 214 proximate the center of the ball 210.

[0068] It will be appreciated that the shape of the mass and its weight distribution - be it of symmetrical shape with a consistent, symmetric weight distribution or of an asymmetrical shape with a variable, asymmetric weight distribution - affect the rebound characteristics of the ball 210, and do so in accordance with the positioning of the mass 214 relative to the center of the ball 210. In some embodiments, the mass 214 is of symmetric shape. In some embodiments, the mass 214 is spherical and has a symmetric weight distribution. In some embodiments, the mass 214 is spherical and the bladder 212 is spherical, and the mass 214 is held by the foam 220 so as to place the center of the mass 214 proximate the center of the ball 210. In some embodiments, the mass 214 is spherical and the bladder 212 is spherical, and the mass 214 is held by the foam so as to place the center of the mass 214 at proximate the center of gravity of the bladder 212.

[0069] In some embodiments, the mass 214 is solid. In other embodiments, the mass is hollow. In other embodiments, the mass 214 is hollow (as explained at Fig. 4 for mass 114) and retains a fill material to provide weight and affect rebound. In some embodiments, the fill material is selected from the group consisting off lead beads, steel beads or other metal alloys. In other embodiments the fill material is selected from the group consisting of polyester, acetate, cellulose, cotton or other fibers. Selection of these materials can be made so that the rebound of the ball can be in the 5 to 25% range.

[0070] An illustration of the rebound of the foam ball 210 is shown in Fig. 3. Fig. 3A shows the ball 210 at rest at an initial height prior to dropping. Fig. 3B shows the ball 210 after being released and at the moment of impact with the base line (e.g., ground). Fig. 3C represents the ball 210 after impact, where it is appreciated that, as the bladder 212 and foam 220 compress upon impact, the mass 214 further compresses the foam 220. Fig. 3D shows the ball 210 as it begins its rebound. The ball 210 and bladder 212 change direction, and, at a fractional time later, the mass 214 changes direction. The time lag represents the dampening effect of the mass. Fig. 3E represents the ball at its maximum rebound when has been damped by mass 214 (particularly as compared to the example of the traditional ball 10 of Fig. 1). The amount that the rebound is retarded is a function of the dynamic properties of the foam, the compressive modulus of the foam, the weight of the mass and the geometry of the mass.

[0071] In light of the foregoing, it should be appreciated that the present invention significantly advances the art by providing a sports ball that is structurally and functionally improved in a number of ways. While particular embodiments of the invention have been disclosed in detail herein, it should be appreciated that the invention is not limited thereto or thereby inasmuch as variations on the invention herein will be readily appreciated by those of ordinary skill in the art. The scope of the invention shall be appreciated from the claims that follow.