The disclosure relates to inflatable sports balls.
A variety of inflatable sport balls, such as a soccer ball, conventionally exhibit a layered structure that includes a casing, an intermediate structure, and a bladder. The casing forms an exterior portion of the sports ball and is generally formed from a plurality of durable and wear-resistant panels joined together along abutting edge areas (e.g., with stitching, adhesives, or bonding), i.e., via a seam. Designs such as decorative elements and holistic textural patterns may be applied to the exterior surface of the casing. Decorative elements are conventionally applied via processes such as thermal transfer films or a release paper. Textural patterns are conventionally applied via processes such as embossing, debossing, stamping, molding, or laser etching.
The intermediate structure forms a middle portion of the sports ball and is positioned between the casing and the interior. Among other purposes, the intermediate structure may provide a softened feel to the sport ball, impart energy return, and restrict expansion of the bladder. In some configurations, the intermediate structure or portions of the intermediate structure may be bonded, joined, or otherwise incorporated into the casing as a backing material. In other configurations, the intermediate structure or portions of the intermediate structure may be bonded, joined, or otherwise incorporated into the interior.
A sports ball is provided. The sports ball may include an interior bladder and a cover disposed about the interior bladder. The cover may comprise a plurality of adjoining panels. The plurality of panels may collectively form an outer substrate, which defines an outer substrate surface. The outer substrate surface may define a plurality of plateau sections.
The cover may further define a feature surface radially spaced apart from the outer substrate surface. The feature surface may define a plurality of indentations positioned between the plateau sections. Each indentation comprises a first shoulder portion positioned at a first boundary, a second shoulder portion positioned at a second boundary, an indentation width disposed between the first boundary and the second boundary, and an indentation terminus disposed on the feature surface and radially spaced apart from the outer substrate surface by an indentation depth.
The feature surface may further define a plurality of protrusions disposed on the plateau sections. Each protrusion extends from the outer substrate surface to a protrusion terminus disposed on the feature surface and radially spaced apart from the outer substrate surface by a protrusion height. At least one of the protrusions is disposed a predetermined distance from at least one of the first boundary or the second boundary of a respective indentation.
While the present disclosure may be described with respect to specific applications or industries, those skilled in the art will recognize the broader applicability of the disclosure. Those having ordinary skill in the art will recognize that terms such as “above,” “below,” “upward,” “downward,” etc., are used descriptively of the figures, and do not represent limitations on the scope of the disclosure, as defined by the appended claims. Any numerical designations, such as “first” or “second” are illustrative only and are not intended to limit the scope of the disclosure in any way.
The terms “comprising,” “including,” and “having” are inclusive and therefore specify the presence of stated features, steps, operations, elements, or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, or components. Orders of steps, processes, and operations may be altered when possible, and additional or alternative steps may be employed. As used in this specification, the term “or” includes any one and all combinations of the associated listed items. The term “any of” is understood to include any possible combination of referenced items, including “any one of” the referenced items. The term “any of” is understood to include any possible combination of referenced claims of the appended claims, including “any one of” the referenced claims.
The terms “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably to indicate that at least one of the items is present. A plurality of such items may be present unless the context clearly indicates otherwise. All numerical values of parameters (e.g., of quantities or conditions) in this specification, unless otherwise indicated expressly or clearly in view of the context, including the appended claims, are to be understood as being modified in all instances by the term “about” whether or not “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows some slight imprecision (with some approach to exactness in the value; approximately or reasonably close to the value; nearly). If the imprecision provided by “about” is not otherwise understood in the art with this ordinary meaning, then “about” as used herein indicates at least variations that may arise from ordinary methods of measuring and using such parameters. In addition, a disclosure of a range is to be understood as specifically disclosing all values and further divided ranges within the range.
Features shown in one figure may be combined with, substituted for, or modified by, features shown in any of the figures. Unless stated otherwise, no features, elements, or limitations are mutually exclusive of any other features, elements, or limitations. Furthermore, no features, elements, or limitations are absolutely required for operation. Any specific configurations shown in the figures are illustrative only and the specific configurations shown are not limiting of the claims or the description.
The following discussion and accompanying figures disclose various sports ball configurations and methods relating to manufacturing of the sport balls. Although the sports ball is depicted as a soccer ball in the associated Figures, concepts associated with the configurations and methods may be applied to various types of inflatable sport balls, such as basketballs, footballs (for either American football or rugby), volleyballs, water polo balls, etc. and variety of non-inflatable sports balls, such as baseballs and softballs, may also incorporate concepts discussed herein.
Referring to the drawings, wherein like reference numerals refer to like components throughout the several views, a sports ball 10 is provided. In a general sense, the sports ball 10 of the present disclosure includes a plurality of outer panels 28 that each have a surface texture 45 formed thereon comprising a plurality of indentations 34 positioned between a plurality of plateau sections 35, and a plurality of protrusions 23 additively applied to the plateau sections 35 near the adjacent indentations 34. The protrusions 23 are disposed upon the respective plateau section 35 as close to the adjacent indentation 34 as possible, to allow the respective protrusion 23 to function as a small tab-like structure projecting from the trailing edge or shoulder portion 29a, 29b of the adjacent indentation 34. For example, the protrusion 23 may act as a wickerbill on the ball 10, such that, in flight, the protrusion 23 operates to trip the boundary layer of air surrounding the ball 10 from laminar to turbulent flow just before the air flows into the respective indentation 34. This forced alteration of the airflow around the ball 10 from laminar flow to turbulent flow at a predetermined point promotes stability and consistency of the ball 10 during flight.
As shown in
In a non-inflatable example configuration of the sports ball 10, the interior 16 may be one of a solid mass or a hollow mass, fixed in size. In an inflatable example configuration of the sports ball 10, the interior 16 may be an interior bladder (
The cover 12 forms an exterior portion of the sports ball 10. The term cover 12 is meant to include any layer of the sports ball 10 that surrounds the interior 16. Thus, the cover 12 has a thickness 88 and may include both the outer substrate layer 24, i.e., the outermost layer as well as any intermediate cover layers 22, 26, which are disposed between the interior 16 and the exterior surface 13. As shown in
In some embodiments, the outer substrate layer 24 may be a composed of a polymeric material, a polymer foam material, or the like. Examples of suitable polymer materials include, but are not limited to, polyurethane, polyvinylchloride, polyamide, polyester, polypropylene, polyolefin, and the like.
The intermediate structure 14 may include a first intermediate cover layer 26 and a second intermediate cover layer 22. The first intermediate cover layer 26 is positioned between the outer substrate layer 24 and the second intermediate cover layer 22. The second intermediate cover layer 22 is positioned between the first intermediate cover layer 26 and the interior bladder 16. The second intermediate cover layer 22 may include the inner substrate surface 20, wherein the inner substrate surface 20 is positioned adjacent to the ball interior 16.
The respective intermediate cover layers 22, 26 of the intermediate structure 14 may be composed of a polymeric material, a polymer foam material, a foam material, textiles, or the like. Examples of suitable polymer materials include, but are not limited to, polyurethane, polyvinylchloride, polyamide, polyester, polypropylene, polyolefin, and the like. Examples of suitable polymer foam materials include, but are not limited to, polyurethane, ethylvinylacetate, and the like. Examples of suitable textile materials include, but are not limited to, a woven or knit textile formed from polyester, cotton, nylon, rayon, silk, spandex, or a variety of other materials. A textile material may also include multiple materials, such as a polyester and cotton blend. The intermediate structure 14 may further provide a softened feel to the sports ball, impart energy return, and restrict expansion of the bladder 16, in an inflatable sports ball 10 example. In one example, the outer substrate layer 24 may be formed a thermoplastic polyurethane material (TPU), first intermediate cover layer 26 may be formed from a polymer foam material, the second intermediate cover layer 22 may be formed from one of a polymeric material, a polymer foam material, a foam material, or a textile material.
As shown in
As shown in
As shown in
The panels 28 may be coupled along the abutting edge areas 36 (
As shown in
The indentations 34 may impart various advantages to ball 10. For example, indentations 34 may enhance the aerodynamics of ball 10, provide a greater amount of consistency or control over ball 10 during play, e.g., during kicking, dribbling, or passing, improve ball feel, and provide for water channeling. Indentations 34 may be formed in the cover 12 via a variety of manufacturing processes including, but not limited to, debossing. Examples of a manufacturing process for forming channels or indentations 34 are disclosed in U.S. Pat. No. 9,370,693 to Berggren, et al., which is hereby entirely incorporated by reference herein. U.S. Pat. No. 9,370,693 to Berggren, et al. generally discloses a variety of manufacturing processes that may be utilized to form debossed features in panels. In one example, one of panels is located on a platen. A press plate is positioned above platen and includes a protrusion having a predetermined shape. The protrusion presses into and heats the areas of panel forming the debossed features. The press plate then moves away from panel to substantially complete the formation of the indentation 34 or debossed feature.
Each indentation 34 may be spaced apart from each of the other indentations 34. Accordingly, each plateau section 35 may be disposed between a plurality of indentations 34, and likewise, each indentation 34 may be positioned between a plurality of plateau sections 35. Said another way, the plurality of plateau sections 35 and the plurality of indentations 34 define an alternating and repeating series of the plateaus section 35 and the indentations 34.
Referring to
Further each indentation 34 comprises a first boundary 87 and a second boundary 89, such that the indentation width 61 is disposed between the first boundary 87 and the second boundary 89. Each of the first boundary 87 and the second boundary 89 of the respective indentation 34 border plateau sections 35. Each indentation 34 comprises a pair of shoulder portions 29a, 29b, one shoulder portion 29a positioned at the first boundary 87 and the other shoulder portion 29b positioned at the second boundary 89. The first boundary 87 and the second boundary 89 are spaced apart by the indentation width 61. The indentation terminus 65 is positioned on the feature surface 21 and radially-spaced apart from the outer substrate surface 18 by the indentation depth 67. In one example, the indentation depth 67 may be greater than about 0.5 millimeters, and more particularly may be from about 0.5 millimeters to about 1.0 millimeters.
Referring to
The intermediate structure 14 is positioned between outer substrate layer 24 and the interior bladder 16. The outer substrate layer 24 may be bonded to the intermediate structure 14 at the respective indentation 34. More particularly, the outer substrate layer 24 may be welded directly to the second intermediate cover layer 22 at the indentation terminus 65 of the respective indentation 34 (
The specific configuration of the indentations 34 may vary considerably. Referring to
Referring to
Alternatively, the indentations 34 may include an exterior portion 82 and an interior portion 84 that exhibit substantially squared configurations (
As shown in
In
As shown in
In one example, as illustrated in
The feature surface 21 may further define a plurality of protrusions 23 disposed on and additively applied to the outer substrate surface 18 at the plateau sections 35. Each of the protrusions 23 may have a protrusion terminus 62 positioned on the feature surface 21 and radially-spaced apart from the outer substrate surface 18 in the second direction 19 away from the inner substrate surface 20 by a protrusion height 64.
In some example embodiments, each of the plurality of protrusions 23 may comprise a dimensional ink. The dimensional ink may be a solvent-based ink, a resin-based ink, a puff ink, a water-based ink, a water-based silicone ink, or the like suitable for additive manufacturing and/or dimensional printing via an additive manufacturing process. The dimensional ink may also include a Polyurethane powder to add texture to the ink. The dimensional ink may also include an organic compound such as Cyclohexanone (CH2)5CO. The dimensional ink may be clear in color, such that the dimensional ink is transparent or translucent. The dimensional ink may also be pigmented to a predetermined coloration. A mechanoluminescent material may be embedded in the dimensional ink.
More particularly, the dimensional ink may be a hybrid ink containing a polyurethane resin component and a puff ink component. The dimensional ink may also include an organic compound such as Cyclohexanone (CH2)5CO. The dimensional ink may also be a solvent-based ink containing a polyurethane resin component, an additive component, and an organic compound such as Cyclohexanone (CH2)5CO; in such examples, the viscosity of the solvent-based ink is from about 150 Decipascal seconds (dPas) to about 600 dPas and the solid content is from about 28% to about 37%.
As shown in
As illustrated in
In one example embodiment, the protrusion height 64 may be greater than about 0.05 millimeters. More particularly, the protrusion height 64 may be from about 0.07 millimeters (mm) to about 0.15 millimeters (mm). In such examples, it is beneficial for the height 64 to be at least 0.05 millimeters (mm) and less than 0.15 millimeters (mm) in order to enhance playability of the ball 10. Protrusions 23 having heights 64 in the aforementioned range exhibit the desired grip or contact between a user and/or player's hand or foot and the exterior surface 13 of the ball 10, while still allowing the ball 10 to maintain desired aerodynamic and flight characteristics.
The plurality of protrusions 23 may include at least a first protrusion 23a and a second protrusion 23b, which are positioned on a respective plateau section 35 such that they extend along and are proximate to a boundary 87, 89 of a respective indentation 34. More particularly, at least one protrusion 23 is positioned a predetermined distance 100 from each boundary 87, 89 of a respective indentation 34.
In one example embodiment, illustrated in
As shown in
In another example, shown in
As shown in
As illustrated in the examples shown in
The respective protrusion 23a, 23b positioned the predetermined distance 100 from one of the first boundary 87 and the respective protrusion 23a, 23b positioned the predetermined distance 100 from the second boundary 89 of an adjacent indentation 34 increases a pressure on the pressure side of the protrusion 23a, 23b, i.e., the plateau section 35 side, and decreases a pressure on the suction side or indentation 34 side of the protrusion 23a, 23b. At the same time, a wake of air downstream of the protrusion 23a, 23b, which contains a pair of counter-rotating vortices, becomes trapped within the respective downstream indentation 34. The presence of the trapped air within the downstream indentation 34 lowers the friction coefficient on the surface of the ball 10, allowing air to flow past the protrusion 23a, 23b and the trapped air within the indentation 34 while maintaining attachment of the boundary layer of air flow to the exterior surface 13 of the ball 10 all the way to the trailing edge of the indentation 34 side of the protrusion 23a, 23b.
This forced alteration of the flow of air around the ball 10, e.g., tripping the boundary layer from laminar flow to turbulent flow at a predetermined point on the ball 10, increases lift on the ball 10 and promotes stability and consistency of the ball 10 in flight, which thereby reduces the likelihood of, for example, unwanted dip of the ball 10 during a driven shot on goal by a player toward the end of the driven shot. Ball consistency is one property that is often commented on by players. The most consistent balls are the ones with the optimum combination of amplitude and frequency of the varying force coefficients relative to the amount of spin.
Comparative testing supports that a ball 10 having protrusions 23a, 23b with a protrusion height 64 greater than 0.05 millimeters and positioned the predetermined distance 100 of less than 1.0 millimeters from a respective boundary 87, 89 of a respective indentation 34, travels more consistently and/or wobbles less in flight than an example ball 10 having the same arrangement of indentations 34 with alternate positioning of the protrusions 23a, 23b, as well as an example ball 10 having the same arrangement of indentations 34 with no protrusions 23a, 23b.
Referring again to
As shown in
The detailed description and the drawings or figures are supportive and descriptive of the present teachings, but the scope of the present teachings is defined solely by the claims. While some of the best modes and other embodiments for carrying out the present teachings have been described in detail, various alternative designs and embodiments exist for practicing the present teachings defined in the appended claims.
This application claims the benefit of U.S. Provisional Application No. 62/870,419, filed Jul. 3, 2019, which is hereby incorporated by reference in its entirety.
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