Patent Grant
7470203
The present disclosure is directed to recreational products, and more particularly to play balls containing a foamed material.
Many play balls have been developed for use in various sports, games, and other recreational activities. In many of these activities, the play balls are relatively soft, such as being formed from a foamed material, and the balls are intended to be caught by a child or other participant. These conventional balls provide a safe way to participate in these activities because the foamed material is soft and absorbs the energy of impact. Similarly, the compressibility and resiliency of the foamed material enables the ball to strike participants or other objects without injury. Because a foam ball does not rely upon an inflated bladder to provide its shape and/or properties, foam balls tend to be more durable than bladder-based balls. For example, a foam ball may be punctured or cut and will generally retain its original construction and properties.
Current foam balls are generally made by one of two methods. One is to start with a quantity, or bun, of foam material, usually polyurethane foam, and grind it into the desired shape. For example, this bun may be ground to a sphere, a football shape, etc. The exterior surface of this ball is often simply the raw foam material. In other words, the surface and interior of the ball have the same construction. In a variant of this conventional process, a surface coat is sprayed or otherwise coated onto the shaped foam.
The second conventional method is to mold the ball using a two-part polyurethane system. The two parts of the polyurethane system are mixed and then dispensed into a mold. The mixed materials are secured within the mold and then cured with heat. The foam expands to fill the cavity and then hardens into the final product. In this process, the surface finish of the ball is formed in one of two ways. First, a “self-skinning” foam is used in which the foam itself forms a skin on the surface of the ball. The second is to spray a “barrier coat” on the surface of the mold prior to dispensing the foam. This sprayed-on surface then becomes the surface of the ball. Both of these methods provide a surface that is cosmetically pleasing but has relatively low friction and therefore makes the ball somewhat slick and difficult to grasp, such as when throwing or catching the ball.
While the construction of these foamed play balls makes them suitable for use by children and/or in settings where hard or full-sized sporting articles are not appropriate, the resilient nature of these balls tends to make them harder to catch and to accurately throw due to the spongy, resilient construction of the ball and the lack of an effective grip surface on the exterior of the ball.
The present disclosure provides compressible, foamed play balls that are at least substantially formed from a foamed material and which include an exterior surface that is partially formed from the foamed material and partially formed from discrete regions of a different material that provides a grip-enhancing structure. In some embodiments, the grip-enhancing structure is formed from an elastomer. In some embodiments, the grip-enhancing structure has at least one of greater friction, greater density, greater weight, increased tackiness, decreased porosity, tread structure, projecting tread structure, and/or decreased compressibility than the foamed material. Methods for forming foamed play balls with grip-enhancing structures are also disclosed.
The present disclosure is directed to play balls that are substantially formed from a foamed material. Play balls 10 according to the present disclosure may have any suitable regular or irregular shape. For example, the play balls may have spherical shapes, or shapes that resemble conventional sports balls, such as footballs, soccer balls, baseballs, tennis balls, softballs and the like. Illustrative, non-exclusive examples of play balls constructed according to the present disclosure are shown in
As illustrated in
Although not required, play balls 10 will typically have a cross-sectional area in at least one dimension of less than 100 in2, and in some embodiments, less than 80 in2, less than 50 in2, less than 30 in2, less than 20 in2, less than 10 in2, in the range of 6-20 in2, in the range of 10-40 in2, and in the range of 20-30 in2. Play balls with cross-sectional areas that are outside of these illustrative ranges are still within the scope of the present disclosure. Play balls 10 according to the present disclosure may be sized to be thrown and/or caught by a user with a single hand, although it is within the scope of the present disclosure that play balls 10 may also have larger sizes that are more suitable for two-handed catches and/or throws.
Foamed material 30 may, but is not required to, form at least a majority of the body's uncompressed volume. In some embodiments, at least 60%, at least 75%, or more of the body's uncompressed volume is formed from foamed material 30. Accordingly, many play balls 10 according to the present disclosure may be described as having an internal region 24 that is at least substantially, if not completely, formed from foamed material 30. As used herein, the term “foamed material” is intended to refer to any suitable number (one or more), composition(s), and/or density(ies) of foamed materials that collectively form a majority (by uncompressed volume) of the play ball. Illustrative, non-exclusive examples of suitable foamed materials include polyurethane, such as two-part curable polyurethane foams, although others may be used.
The foamed material forming foamed region 32 of the play ball's exterior surface 22 may have the same construction and composition as the portion of the rest of the ball's body 20 that is formed from foamed material 30. For example, foamed region 32 may be formed from raw foam that does not include a surface layer having a different composition, density, or the like as the foamed material present beneath the ball's exterior surface. As another illustrative, non-exclusive example, the foamed material 30 forming foamed region 32 of the ball's exterior surface may have a surface coating, as indicated in dashed lines at 34 in
Play balls 10 according to the present disclosure are compressible, which enables them to be easily squeezed within a user's, even a child's, hand, while also being resilient so that they are biased to automatically return to their neutral, or uncompressed, configuration. As used herein, “compressible” refers to a material that is adapted to be compressed to at least 60%, if not at least half, at least 40%, or even at least 25%, at least 10%, or less, of its original dimension (such as at least one of diameter, width, and length) by squeezing the material between a user's fingers or otherwise within a user's hand. Accordingly, a “compressible, resilient” play ball according to the present disclosure is designed and/or otherwise adapted to be compressed to a reduced dimension (such as one of the illustrative dimensions described, illustrated, and/or incorporated herein) by a user squeezing the ball between the user's fingers or otherwise squeezing the ball in the user's hand.
Foamed material 30 may be selected or otherwise tailored to have selected properties depending on the intended use of the play ball 10 formed therefrom. Properties that can be controlled, or influenced, by the selected foamed material include, but are not limited to, one or more of the density, weight, stiffness, surface finish, color, and resilience of the material. For example, the resiliency of the foamed material affects the bounce, or spring, in the play ball, such as when it strikes a surface or when a user tries to catch it. The weight of the foamed material also affects the distance that the play ball will travel when thrown with a particular force, as well as the force of impact of the play ball. For example, when forming a play ball 10 that is intended to be thrown outdoors, such as for longer distances, it may be desirable for the play ball to have more weight, such as by being formed from a denser foamed material, than a play ball 10 that is intended for indoor use. By selecting the resiliency of the foamed material, the amount of bounce, or rebound, of the foamed ball may be influenced. For example, a less resilient foamed material may be used to make the play ball easier to catch, especially when thrown with force. In this way, it is easier to catch such a play ball because it is less likely to bounce out of a user's hands as the user tries to grasp it. Despite these variables that may be influenced through the selection of the foamed material, the above-discussed limitations of conventional foamed play balls still exist in play balls that do not include grip-enhancing structure 40.
As discussed, play balls 10 according to the present disclosure further include grip-enhancing structure 40 that extends across a portion, but not all, of the exterior surface 22 of the play ball, thereby defining a grip-enhancing region 36 of the exterior surface. Grip-enhancing structure 40 is formed from a material having a greater density and less compressibility than foamed material 30. This material may have the same or a different composition from the foamed material. In some embodiments, the material from which the grip-enhancing structures are formed and the foamed material may have at least one common component. Grip-enhancing structure 40 preferably is formed from one or more materials having greater friction (and/or coefficient of friction) and/or tackiness than the foamed material, thereby promoting a better grip by a user than a conventional foam ball that does not include grip-enhancing structure 40. Similarly, the grip-enhancing structure may (but is not required to) be formed from one or more materials having greater density than the foamed material, thereby promoting increased weight in a play ball constructed according to the present disclosure than in a play ball that does not include grip-enhancing structure 40. While not required, increased relative weight positioned at the exterior surface of the ball may also be selectively used to increase the rotational inertia of the play ball, such as a football-shaped play ball, when thrown. Grip-enhancing structure 40 may, but is not required to, have a reduced porosity than the foamed material. Grip-enhancing structure 40 will typically be formed from a flexible material, and may be formed from a resilient and/or elastomeric material.
Grip-enhancing structure 40 will typically be formed from one or more flexible materials, which may or may not be at least partially foamed. Illustrative examples of suitable materials for grip-enhancing structure 40 include thermoplastic and other elastomers having soft touch and high friction, such as a styrenic block copolymer (SBC). A common brand name for SBC is Kraton™. An illustrative, non-exclusive example of such a styrenic material is 30 Shore A Kraton. Other illustrative examples of suitable materials for grip-enhancing structure 40 include polyurethane, PVC, and mixtures and compounds thereof. Further illustrative examples include 70 Shore A Dow Pellathane thermoplastic urethane, and 60 Shore A BASF Elastollan. The materials from which the grip-enhancing structure and the foamed material are formed may be selected so that the foamed material adheres to the grip-enhancing structure, such as in embodiments of the play ball where the foamed material is added as a liquid to a mold containing the grip-enhancing structure. In some embodiments, the materials may be selected to be adapted to be adhered or otherwise bonded together through the use of a suitable adhesive.
The grip-enhancing structure extends over, or forms, a portion of the play ball's exterior surface. More specifically, the foamed material and the grip-enhancing structure each form discrete regions of the exterior surface, such as the previously discussed regions 32 and 36. It is within the scope of the present disclosure that either the foamed material or the grip-enhancing structure may form the majority of the play ball's exterior surface. However, grip-enhancing structure 40 will typically extend over, or form, less than half of the exterior-surface of the play ball, including such illustrative examples as 10-50%, 15-40%, 20-45%, 25-50%, less than 40%, less than 25%, at least 15%, etc. of the surface area of the exterior surface of the play ball.
Grip-enhancing structure 40 may be formed from a continuous length of material or two or more regions that, at least on the exterior surface of the play ball, are spaced-apart from each other and surrounded by foamed material 30. For example, the grip-enhancing structure may extend around the diameter of the play ball's exterior surface, around two or more sections of the play ball's exterior surface, along one or more axes of curvature of the play ball's exterior surface, in discrete locations on the exterior surface, in radially spaced configurations relative along the exterior surface, in randomly or non-uniformly spaced configurations on the exterior surface, etc. The above-referenced
Grip-enhancing structure 40 includes an exterior portion 42 that may extend in a variety of orientations relative to the portion, or region, 32 of exterior surface 22 that is formed by foamed material 30. For example, and as indicated somewhat schematically in
As discussed in more detail herein, it is within the scope of the present disclosure that the grip-enhancing structure may include two or more components, which are either separately secured on the exterior surface of the play ball, or connected to the exterior surface in groups of two or more. The grip-enhancing structure may be shaped to correspond to the curvature of the portion of the exterior surface that it is intended to represent. As an illustrative graphical example,
It is also within the scope of the present disclosure that the grip-enhancing structure may include regions that extend, or otherwise project, from exterior portion 42 of the grip-enhancing structure into the interior region of the play ball. The example of grip-enhancing structure 40 shown in
In
Another illustrative example of an internal portion 46 for grip-enhancing structures according to the present disclosure is internal portions that interconnect spaced-apart exterior portions 42. In such a configuration, the grip-enhancing structure may be described as including exterior portions 42 that are connected by linkages, or bridges, 54 that are adapted to extend beneath the exterior surface of the play ball. The linkages may enable the exterior portions to be positioned as a group, rather than individually. The linkages may also cooperate to secure, or anchor, the grip-enhancing structure to the foamed material by forming internal projections around which the foamed material extends. Illustrative examples of grip-enhancing structures 40 that include internal linkages 54 interconnecting spaced-apart exterior portions 42 are shown in
Although discussed as having bodies that are at least substantially formed from foamed material 30, it is within the scope of the present disclosure that play balls 10 may include bodies 20 that include a central void, or cavity, 60 or a central core 62 that is formed from a solid material 64. A solid core will provide a play ball having greater weight than an otherwise constructed play ball that does not include such a core, while a play ball having a central void may be more compressible and will be somewhat lighter than a similarly constructed play ball without such a void. Schematic representations of these illustrative internal constructions are shown in
It is also within the scope of the present disclosure that the body of the play ball may include internal supports 70, such as inserts 72 and/or frames 74, that are separately formed from the foamed material and which are adapted to position and/or support the grip-enhancing structure. For example, preformed foamed or and/or flexible inserts 72 may be used to interconnect portions of the grip-enhancing structure, such as spaced-apart regions on a continuous length of grip-enhancing structure or to interconnect separately formed components of the grip-enhancing structure. For example, the frame or insert may include mounts 76 that are positioned and/or shaped to receive a corresponding portion of the grip-enhancing structure, such as may (but is not required to) include a complimentary mount or connecting portion. Flexible frames may be formed from such illustrative materials as polyethylene and/or polypropylene, amongst others, and may have foamed or non-foamed constructions. Inserts 72 and frames 74, when present, will typically have a resilient and/or compressible construction.
Illustrative examples of internal supports are shown in
Any suitable process or method may be used to form play balls 10 according to the present disclosure, such as the play balls described, illustrated, and/or incorporated herein. In other words, play balls 10 having an exterior surface 22 having at least one discrete foamed region 32 and at least one discrete grip-enhancing region 36, including exterior surfaces where the foamed region forms a majority portion of the exterior surface, are within the scope of the present disclosure regardless of the method used to form the play ball. However, illustrative and non-exclusive examples of suitable methods for forming play balls 10 are described, illustrated and/or incorporated herein.
At 106, the grip-enhancing structures are secured to the body portion. The grip-enhancing structure will in at least this example typically be separately formed from the foamed ball, such as by molding, cutting, stamping, etc., and thereafter positioned and secured relative to the foamed ball. This securing step may utilize any suitable process or structure, illustrative, non-exclusive examples of which include adhering the grip-enhancing structure to the foamed material, such as via a suitable adhesive, fixative, or bonding agent. Another example of a suitable securing step includes mechanically securing the grip-enhancing structure to the molded material, such as by inserting portions of the grip-enhancing structure, such as internally projecting portions, into recesses or other sockets or mounts that are formed in the exterior surface of the molded material. As discussed and illustrated herein, the sizing of these recesses, when present, may also be utilized to define the relative position of the grip-enhancing structures exterior portions relative to the outer surface of the molded material. As discussed, at least a portion of the grip-enhancing structure may be recessed beneath the portion of the ball's exterior surface that is formed by the foamed material, the grip-enhancing structure's exterior surface may be positioned at, below, or above the portion of the ball's exterior surface that is formed by the foamed material, and/or at least a portion, if not all, of the grip-enhancing structure may extend above (or project outwardly from) the portion of the ball's exterior surface formed by the foamed material.
When recesses are formed in the foamed material to receive the grip-enhancing structure, the recesses may be (slightly) undersized relative to the grip-enhancing structure to be received therein. For example, this may enable the recesses to provide compression to the grip-enhancing structure. It is also within the scope of the present disclosure that the recesses, when present may be precisely sized to receive the grip-enhancing structure, or oversized relative to the grip-enhancing structure to thereby provide a depression or transition region between the portions of the exterior surface formed by the foamed material and the grip-enhancing structure. Additionally, or alternatively, the grip-enhancing structures may be adhesively retained within the recesses.
In a further variation of the above methods that begin by forming and shaping a foam ball, the foam ball may be masked or otherwise coated or covered in selected regions, with the grip-enhancing structure subsequently coated, sprayed, or otherwise applied to the foam ball, such as on the non-masked or uncovered regions. This variant of previously discussed methods that utilize preformed grip-enhancing structures is indicated at 112 in
Additional illustrative, non-exclusive examples of suitable methods for forming play balls 10 according to the present disclosure are schematically illustrated in
At 122, methods 120 include positioning the grip-enhancing structure(s) 40 relative to the mold, such as relative to the interior surface of the mold cavity. This positioning may utilize any suitable method and/or structure, illustrative, non-exclusive examples of which are indicated in
The interior surface of the mold may be a smooth surface, in which case the grip-enhancing structure and foamed material may be used to produce a play ball with a smooth exterior surface in which the exterior portions of the grip-enhancing structure and the foamed material are at generally the same level. However it is also within the scope of the present disclosure that the mold's interior surface may include recesses that are sized to receive the grip-enhancing structure therein. In such a construction, the grip-enhancing structure will tend to project outwardly from the foamed material. In a further variation, the mold's interior surface may include mounts or other projections that are adapted to extend into the mold cavity to engage the grip-enhancing structure.
In each of these illustrative examples of positioning steps, the grip-enhancing structure is preformed relative to the foamed portion of the play ball. This does not require, in all embodiments, that the grip-enhancing structure is preformed prior to being inserted into the mold cavity. For example, a liquid material from which grip-enhancing structure is formed upon curing (through any suitable method or process) may be applied to regions of the mold cavity, such as recesses within the mold cavity. However, in many embodiments, the grip-enhancing structure will be formed prior to being inserted into the mold cavity, such as by molding, cutting, stamping, and/or another suitable process, and thereafter positioned in the mold.
When the grip-enhancing structure is bonded to the interior surface of the mold, any suitable adhesive or other bonding agent may be used. The mold cavity may be smooth or otherwise not define predetermined locations for grip-enhancing structure. Additionally or alternatively, the mold may define regions to which the grip-enhancing structure is to be bonded. Illustrative, somewhat schematic examples of molds, or mold portions, 80 that include interior surfaces 82 to which grip-enhancing structure 40 is bonded are shown in
In
When the grip-enhancing structure is mechanically attached to the mold's interior surface, the mechanical attachment step also refers to a process that is adapted to only temporarily retain the grip-enhancing structure in a selected position relative to the mold's interior surface. For example, this step may utilize releasable fastening or retention mechanisms that are designed to release the grip-enhancing structure when the ball and the corresponding mold portion are drawn away from each other. However, unlike a chemical process, the mechanical attachment utilizes friction or a similar mechanical mechanism to retain the grip-enhancing structure in a selected, or defined, position relative to the mold's interior surface.
Illustrative examples of suitable mechanisms for mechanically attaching the grip-enhancing structure to the mold include forming internal recesses that extend generally into the mold and away from the mold's internal cavity 84 and/or including projections, or projecting members, that generally extend away from the mold's interior surface and into the mold's internal cavity. These recesses and/or projections are adapted to mechanically couple to the grip-enhancing structure to frictionally retain the grip-enhancing structure in a selected position, or range of positions, relative to the mold's interior surface. In some embodiments, the recesses and/or projections may be adapted to apply compression to the grip-enhancing structure. When the corresponding portion of the mold's interior surface has a concave configuration, this compression urges the grip-enhancing structure against the mold and/or to conform to the shape of the mold's interior surface against which it is compressed. The above references to the recesses being coupled to the grip-enhancing structure and/or applying compression thereto may alternatively be described in the context of sidewalls or other surface(s) that define the recess and which engage the grip-enhancing structure and/or apply compression thereto. The recesses and projections described above may additionally or alternatively be referred to as mounts that form a portion of the mold and which are adapted to mechanically retain the grip-enhancing structure in a defined or selected position relative to the mold's interior surface.
As discussed, mounts 160 may be adapted to apply compression to the grip-enhancing structure to conform this structure to the interior surface 82 of the mold. This compressive force may (but is not required to in all embodiments) also provide a temporary seal between the grip-enhancing structure and the mold. This seal may restrict the foamed material from extending over the exterior portion 42 of the grip-enhancing structure (i.e., the surface of the grip-enhancing structure that faces the interior surface of the mold) when the foamed material is injected or otherwise inserted into the mold.
As indicated above, when a molding process is used to construct a play ball 10 according to the present disclosure, it is desirable to restrict the foamed material from extending over the exterior surface of the grip-enhancing structure. Recessing the grip-enhancing structure within a recess in the mold is one method that may be used to accomplish this objective. Others include compressing the grip-enhancing structure against the interior surface of the mold and/or to provide a mount that extends into the mold cavity and extends around the perimeter of the grip-enhancing structure. When the perimeter of the grip-enhancing structure is not enclosed within a mount or recess, the perimeter of the grip-enhancing structure may itself be adapted to form a temporary seal with the interior surface of the mold to prevent the foamed material from passing between the grip-enhancing structure and the mold when the foamed material is inserted into the mold.
Although not required, in the illustrated examples shown in
When the grip-enhancing structure includes an internal frame portion or is coupled to an internal frame that extends within the body of the play ball, the grip-enhancing structure and this frame or support may be positioned within the mold simply by placing this structure within the mold. In other words, the frame or support may sufficiently urge the grip-enhancing structure against the mold's internal surface to position the grip-enhancing structure against this surface of the mold. The previously discussed inserts may also provide this positioning. As also discussed, the support or frame may include mounts that are adapted to interconnect with the grip-enhancing structure, either generally or by engaging corresponding receivers or coupling structure on the grip-enhancing structure. It is also within the scope of the present disclosure that the supports, frames, and/or inserts physically contact the grip-enhancing structure to urge the structure against the mold, without having a chemical bond or mechanical linkage between the grip-enhancing structure and the support or frame (i.e., a linkage that would remain if this structure was removed from the mold). Instead, adjacent surfaces of this structure are pressed against each other to urge the grip-enhancing structure against the interior surface of the mold. This biasing of the grip-enhancing structure may be provided by the frames, supports, and/or inserts that are described, illustrated and/or incorporated herein. As also discussed, this biasing may be utilized in combination with other processes or steps, such as the bonding, mechanically attaching, and/or compressing steps described, illustrated and/or incorporated herein. This optional biasing step is schematically illustrated in dashed lines in
After positioning the grip-enhancing structure within the mold, such as in a selected or predefined position relative to the mold's interior surface, the foamed material is then inserted into the mold cavity. This is indicated in
As discussed above, grip-enhancing structure 40 may include a single length of material, discrete regions of material that are joined by internal bridging, or linking, structure that extends beneath the exterior surface of the play ball, or separate regions of material that are positioned relative to each other by an internal frame or support that extends within the body of the play ball and beneath the exterior surface of the play ball. When the grip-enhancing structure is formed from a single length of material (or single extent of interconnected exterior portions), this material may be supported by an internal frame or support that extends within the body of the play ball and beneath the exterior surface of the play ball. Many of the above examples illustrate methods in conjunction with a plurality of separate grip-enhancing structures. It is within the scope of the present disclosure that any of the grip-enhancing structures disclosed, illustrated and/or incorporated herein may be utilized, including grip-enhancing structures that include internal projections and/or linkages.
As discussed, play balls according to the present disclosure have discrete regions of two different materials on the exterior surface thereof, with one of these materials being a foamed material and the other forming a grip-enhancing material that forms an enhanced-grip region of the play ball's exterior surface. The enhanced-grip region may be described as including a grip-enhancing structure that is formed from a different material than the foamed material. This difference in material may relate to one or more of the compositions, densities, porosities, friction, coefficient of friction, weight, tackiness, compressibility, and the like of the material(s) from which the foamed region is formed and the material(s) from which the grip-enhancing structure is formed. In some embodiments, the grip-enhancing structure is formed from an elastomer, such as an elastomer that provides a higher friction surface that promotes a surer grip than if the grip-enhancing structure was not present on the play ball's exterior surface. The two different materials may be of the same or different colors, may be different textures, may provide regions for graphic treatments, may include bumps, ridges, indentations, textures, and the like. Although not required, the use of two different, separately added materials to form the exterior surface of the play ball offers manufacturing options for color and/or texture breaks between these materials, which may provide aesthetic options not available with conventional play balls.
It is believed that the disclosure set forth above encompasses multiple distinct inventions with independent utility. While each of these inventions has been disclosed in its preferred form, the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense as numerous variations are possible. The subject matter of the inventions includes all novel and non-obvious combinations and subcombinations of the various elements, features, functions and/or properties disclosed herein. Similarly, where the claims recite “a” or “a first” element or the equivalent thereof, such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements.
It is believed that the following claims particularly point out certain combinations and subcombinations that are directed to one of the disclosed inventions and are novel and non-obvious. Inventions embodied in other combinations and subcombinations of features, functions, elements and/or properties may be claimed through amendment of the present claims or presentation of new claims in this or a related application. Such amended or new claims, whether they are directed to a different invention or directed to the same invention, whether different, broader, narrower, or equal in scope to the original claims, are also regarded as included within the subject matter of the inventions of the present disclosure.
The present application claims priority to U.S. Provisional Patent Application Ser. No. 60/622,144, which was filed on Oct. 25, 2004, and the complete disclosure of which is hereby incorporated by reference for all purposes.
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