COMPOSITE GOLF CLUB GRIP WITH FOAM LAYER

BACKGROUND
Technical Field

The present disclosure generally pertains to grips. More particularly, the present disclosure is related to a golf grip including a foam layer formed from expanded thermoplastic polyurethane (E-TPU).

Related Art

Grips for sporting implements such as golf clubs have taken numerous forms over the years. Early grips commonly had a wrap material, such as leather, in a helical pattern around the handle portion of the golf club. Over the years grips have evolved from the wrap type grip to a tapered cylinder of rubber, polyurethane, TPE, or similar elastomeric and shock absorbing materials that slip over an end of a golf club shaft. These grips are generally formed by a compression molding or an injection molding process. However, the underlistings of existing grips in the lightest form such as those less than 0.35 grams per cubic centimeter (g/cc) are not dimensionally consistent and vary in thickness and length over the surface of the material(s). Light, or lightweight materials are subjected to high pressures during the molding process and when released from the mold relax to a larger form. This larger form is not consistent in size across the material. This causes challenges in maintaining high quality as it relates to length control and the accuracy of cover material to fit a given application.

The choice of rubber and synthetic rubber materials provides multiple benefits for the swinging golf clubs. Rubber is a material that can provide a good coefficient of friction to help the golfer hold the club throughout the swing. Rubber can also dampen vibrations and reduce the magnitude of forces generated by impacting the ball and the ground that reach a golfer's hands, which may prevent injury or reduce the chances of injury.

SUMMARY

An aspect of the disclosure provides a grip. The grip can have a closed end. The grip can have an open end. The grip can have a grip body formed from expanded foam having an outer surface. The grip can have an elongated cavity inward of the outer surface extending from the open end toward the closed end. The expanded foam can be one or more of a thermoplastic polyurethane (E-TPU), an expandable polystyrene (EPS), an expanded polyethylene (EPE), an expanded polypropylene (EPP), and an expanded polylactide (EPLA). The grip can have an outer layer including a laminate material. The outer layer can have one or more openings exposing an associated one or more portions of the grip body. The grip body protrudes through the openings. The grip body can be flush with an outer surface of the outer layer along an exterior surface of the grip. The outer layer can extend from the closed end to the open end. The outer layer can extend beyond the grip body at the open end. The expanded foam can be steam chest molded.

Another aspect of the disclosure provides a grip. The grip can have a grip body formed from expanded foam. The grip body can have a closed end. The grip body can have an open end. The grip body can have an elongated cavity inward of the outer layer and the foam layer extending from the open end toward the closed end.

Other features and advantages of the present invention should be apparent from the following description which illustrates, by way of example, aspects of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the grip mounted to a shaft of a golf club.

FIG. 2A is a perspective view of an embodiment of the grip of FIG. 1 with a portion of the grip cutaway.

FIG. 2B is a perspective view of another embodiment of the grip of FIG. 1 with a portion of the grip cutaway.

FIG. 2C is a cross section of an embodiment of FIG. 2B.

FIG. 2D is a cross section of another embodiment of FIG. 2B.

FIG. 2E is a cross section of another embodiment of FIG. 2B.

FIG. 2F is a perspective view of an embodiment of the grip of FIG. 1 with a portion of the grip cutaway.

FIG. 3 is a perspective view of another embodiment of the grip of FIG. 1 with a portion of the grip cutaway.

FIG. 4 is a perspective view of a further embodiment of the grip of FIG. 1 with a portion of the grip cutaway.

FIG. 5 is a cross-section of a portion of an embodiment of the grip of FIG. 1.

FIG. 6 is a perspective view of the grip of FIG. 1 illustrating an texture layer adjacent to the grip.

FIG. 7 is a perspective view of another embodiment of the grip of FIG. 1 with a portion of the grip cutaway.

FIG. 8 is a detailed view of the portion of FIG. 7 enclosed by rectangle VIII in FIG. 7.

DETAILED DESCRIPTION

The apparatus disclosed herein includes a grip, such as a golf club grip. Other grips are also applicable, such as bicycle grips, motorcycle grips, baseball bat grips, tool grips, as well as many other applications. A golf club grip is a primary example describe herein, however, the disclosure is so limited. The principles of use and details of construction are widely applicable to most any device having a “grip.” In embodiments, the grip includes a construction having an outer layer and an inner layer within the outer layer. The outer layer may provide a seamless surface for a golfer to grasp that does not deflect inward as the golfer grasps a putter for a putting stroke, while the foam layer may provide a reduction in weight of the overall grip. In some embodiments, the grip also includes a core that may dampen or transfer vibration to the outer layer from the shaft.

In some embodiments, the disclosed grip can have a single layer (e.g., both the inner layer and outer layer) comprising the expanded foam material. Other embodiments can have expanded material only as a base- or inner layer. In some other embodiments, the grips can have a combination of both, in which certain areas of the grip can have the expanded foam material comprise the full thickness of the grip. In such an example, “windows” or apertures/openings in the outer layer make the expanded foam material is visible. Other embodiments can have a composite shell as the outer layer with foam as the inner layer within the outer layer.

FIG. 1 is a perspective view of the grip 100 mounted to a shaft 50 of a golf club. FIG. 2 is a perspective view of an embodiment of the grip 100 of FIG. 1 with a portion of the grip 100 cutaway. Referring to FIGS. 1 and 2, grip 100 may be affixed to the end of a shaft 50 opposite, for example, a club head of a golf club. The grip 100 can also be used for other types of grips. Grip 100 include may include an open end 103, a closed end 101, an elongated cavity 109, and a body 108. The open end 103 is opposite the closed end 101 and allows the shaft 50 to be inserted into the elongated cavity 109. The closed end 101 may include a cap 102 that is integral to the body 108. The cap 102 may be joined to the body 108, such as molded, glued, or bonded to the body 108. The cap 102 may be pre-molded prior to being joined to the body 108. The cap 102 may include a vent hole 105, which can be used to install the grip 100 onto the shaft 50 and allow the displaced air and installation solvent to escape from the elongated cavity 109.

The elongated cavity 109 is the hollow interior of the grip 100 formed by the body 108. The elongated cavity 109 may be sized relative to the diameter of the shaft 50 and extends from the open end 103 toward the closed end 101 and may terminate adjacent to the closed end 101. The elongated cavity 109 may have an elongated cavity axis 90. The elongated cavity axis 90 may be coaxial to the axis of the shaft 50 when the grip 100 is installed onto the shaft 50. All references to radial, axial, and circumferential directions and measures refer to the elongated cavity axis 90, unless specified otherwise, and terms such as “inner” and “outer” generally indicate a lesser or greater radial distance from the elongated cavity axis 90.

The body 108 may include an outer layer 110 and an inner layer 120. The outer layer 110 can extend from the closed end 102 to the open end 103. In some implementations inner layer 120 can also extend from the closed end 102 to the open end 103. In some implementations, the outer layer 110 can extend past the inner layer 120, in which case the inner layer 120 may not extend all the way to the open end, terminating at a seam 118. In some other implementations, the opposite configuration is possible in which the inner layer 120 may extend to the open end 103 and the outer layer 110 extends to the seam 118.

An outer surface 111 the outer layer 110 or exterior surface of the grip 100 may be smooth as illustrated in FIG. 2 or may include surface texture 112 as illustrated in FIG. 1. The surface texture 112 may be, inter alia, from the nature of the material used for the outer layer 110, may be formed from an texture layer 114 (shown in FIG. 6) in the outer layer 110, such as a decal, or from a combination thereof. The surface texture 112 may also result from openings in the outer layer 110 that expose a portion/portions of the inner layer 120. In some embodiments, the texture 112 can be formed in the outer layer 110 as a part of the molding process, for example. The texture 112 can further be a feature of the materials used to form the foam of the grip 100. For example, steam chest molded expanded foams may start as small beads or balls. Accordingly, following the molding process, the texture may then have an irregular, bumpy, or pebbled surface as a result of the foam beads used to form the grip 100 (e.g., the single foam layer 130 of FIG. 2F).

In some implementations, the outer layer 110 can also be a soft or supple layer providing a grippable surface to a user. The outer layer 110 can be a laminate applied to the inner layer 120, for example. The outer layer 110 can be in the form of a rubber compound or a sheet form of Polyurethane type material, or other materials beneficial as a gripping interface or one or more synthetic materials (e.g., polymers, rubber, polyurethane, etc.).

In some examples, the outer layer 110 can have a hard outer shell of the body 108. The outer layer 110 may be a composite material that includes a matrix and a reinforcement material. The outer layer 110 may be a laminate composite fiber outer shell. The fiber can be, inter alia, carbon, glass, boron, Kevlar, or a combination thereof. In some examples, the outer layer 110 can be a fiber reinforced plastic. The fiber reinforced plastic may be carbon fiber reinforced polymer, carbon fiber reinforced plastic or carbon fiber reinforced thermoplastic, where the matrix may be a polymer resin, such as epoxy, and the reinforcement is a carbon or synthetic carbon fiber. The polymer resin may be a thermoset or thermoplastic resin. The reinforcement material may include multiple layers of sheets that include the fibers.

The inner layer 120 may be inward from the outer layer 110. The outer layer 110 may surround the inner layer 120. In some examples, the inner layer 120 can be referred to as an underlisting. The inner layer 120 can be an underlisting which is covered with or partially covered with another material forming the outer layer 110. The inner layer 120 may adjoin and be integral to the outer layer 110. The outer layer 110 and the inner layer 120 may be bonded together. In embodiments, the outer layer 110 is formed around the inner layer 120 and bonded to the inner layer 120 during the process of forming the outer layer 110. In some examples, the inner layer 120 and the outer layer 110 be molded as a unitary component and thus form a grip (e.g., the body) as a unitary piece (e.g., the foam layer 130 of FIG. 2F). The inner layer 120 and the outer layer 110 may be formed of the same material an molded as a unitary piece forming the grip 100. The elongated cavity 109 is located inward from the inner layer 120. In the embodiment illustrated in FIG. 2, the inner layer 120 is shaped and constructed to form the elongated cavity 109. The inner layer 120 is a light structural portion of the body 108 and may include expanded or solid foam. The solid foam may include an open or closed cell structure. The closed cell foam may be syntactic foam.

In some implementations, the inner layer 120 can be formed from a closed cell particle foam. These materials can include expanded foam materials. In at least on example, the expanded foam can be expanded thermoplastic polyurethane (E-TPU), such as the Infinergy™ foam manufactured by BASF. The E-TPU has a low bulk weight, with a density of about 110 kilograms per cubic meter, and, after processing on standard molding machines, a molded part weight of between 200 and 320 kilogram per cubic meter. The E-TPU resists absorption of water (e.g., less than two percent by volume in 24 hours) and has a very high breaking elongation (between 100 and 150 percent depending on the density), tensile strength (approx. 600 kilopascals) and abrasion resistance, combined with good chemical resistance. The closed-cell, elastic particle foam combines the properties of TPU with the advantages of foams. Some benefits of E-TPU are low density, high elasticity, outstanding resilience, high abrasion resistance, high tensile strength, good chemical resistance, and good long-term durability in a wide temperature range, among other advantages. In some implementations, the inner layer 120 can also be formed from polyurethane foam. E-TPU is described as a primary example herein, but it should be appreciated that other steam chest moldable, expanded foam materials are possible.

Some common underlistings do not have consistent dimensions across a product. This can include a variation of +/−0.040 inches along the length of certain product. The same underlistings can and have a density greater than 0.3 grams per cubic centimeter (g/cc). On the other hand, forming the inner layer 120 and/or the outer layer 110 from E-TPU or the other materials disclosed herein can result in lower density, for example in the range of 0.20 g/cc. In some embodiments, the density can range between 0.1-0.3 g/cc or 0.1-0.25 g/cc. This kind of inner layer 120 can be processed in short mold times (e.g., 2-3 minutes) and may be capable of consistent sizing where tolerances are more typical+/−0.010 inches. The lower density material allows for products to be lighter, enhancing design freedom, and providing products that meet lower weight specifications with light polyurethane-based cover materials, or that meet existing weight ranges when matched with heavier materials such as rubber-based compounds (e.g., for outer wrap). This provides a substantial advantage over other currently used materials, such as ethylene-vinyl acetate (EVA) underlistings that are not dimensionally consistent when constructed (e.g., molded).

In some implementations, other compositions such as expanded polypropylene (EPP), expanded polystyrene (EPS), expanded polyethylene (EPE), and an expanded polylactide (EPLA), or other expanded materials suitable for steam chest molding can be used as the inner layer 120. The inner layer 120, for example, can be formed from steam chest molded E-TPU, EPP, or EPS. In some other embodiments, any expanded, steam chest moldable materials are useable as the inner layer 120.

The outer layer 110 can be formed of, for example, a rubber compound or a sheet form of polyurethane-type material, or other materials suitable as a gripping interface. Rubber materials may be advantageous in certain applications as they wear better under most environmental conditions (e.g., ultraviolet and weather) than polyurethane materials.

FIG. 2B is a perspective view of another embodiment of the grip of FIG. 1 with a portion of the grip cutaway. The outer layer 110 can have a plurality of openings 125. The openings 125 can be windows or apertures in the outer layer 110 that reveal a portion of the inner layer 120. Two openings 125 are shown as oval shaped however this is not limiting. There can be any number of openings 125 and they can have any shape and be positioned in the outer layer 110 as needed. The inner layer 120 and the outer layer 110 can have different firmness and/or different texture. Thus the openings 125 can provide a variation in the texture of the grip 100, increasing gripping ability and/or comfort of the grip 100. The openings 125 are shown in the embodiment of FIG. 2B, however the openings can be applied to any of the multiple layer embodiments of the grip 100 described herein. For example, the openings 125 can be freely integrated into the embodiments of FIG. 3 through FIG. 8 having the outer layer 110.

FIG. 2C is a cross section of an embodiment of the openings of FIG. 2B. The inner layer 120 can be visible through the openings 125. In the embodiment shown, the outer surface of the inner layer 120 can be flush with the outer surface of the outer layer 110, as shown. For embodiments using different materials to form the inner layer 120 and outer layer 110, such as expanded foam for the inner layer 120 and rubber or PU for the outer layer 110, the openings 125 provide increased texture along the outer surface 111 and increased comfort. The same can be true for the embodiments of FIG. 2D and FIG. 2E, described below.

FIG. 2D is a cross section of another embodiment of the openings of FIG. 2B. As in FIG. 2C, the inner layer 120 can be visible through the openings 125. In the embodiment shown, the inner layer 120 can be extend past the outer surface of the outer layer 110, as shown. This can result in portions of the inner layer protruding through the outer layer 110 (e.g., through the openings 125) and forming an irregular texture along the outer surface 111.

FIG. 2E is a cross section of another embodiment of the openings of FIG. 2B. As in FIG. 2C and FIG. 2D, the inner layer 120 can be visible through the openings 125. In the embodiment shown, the inner layer 120 can be recessed within the openings 125, where the inner layer 120 does not extend into the openings 125. This can form an irregular texture having concave dimples along the outer surface 111 where the openings 125 reveal portions of the inner layer 120.

FIG. 2F is a perspective view of an embodiment of the grip of FIG. 1 with a portion of the grip cutaway. The embodiment shown in FIG. 2F is similar to that shown in FIG. 2A with a unitary grip body having a single foam layer 130. For example, the outer layer 110 and the inner layer 120 can be replaced or combined into a grip body having only the foam layer 130 (e.g., formed from a single material). In some embodiments, the other features of the grip 100 described remain the same, however the single, foam layer 130 is used to form the body 108 of the grip 100, extending from the closed end 101 to the open end 103. Thus the grip 100 can include the foam layer 130 (e.g., the body 108) and the closed end 101 (e.g., with the vent hole 105) formed together from a single material, such as from an expanded foam (e.g., E-TPU). In embodiments of the grip 100 having the foam layer 130, the texture 112 can be added using, for example, the molding process (e.g., steam chest molding) to form texture or other grippable features into the outer surface 111 of the grip 100. Such grippable features may resemble the concave or convex effects of the openings of FIG. 2B, FIG. 2D and FIG. 2E, the texture 112 of FIG. 1, FIG. 7, and FIG. 8, for example.

FIG. 3 is a perspective view of another embodiment of the grip 100 of FIG. 1 with a portion of the grip 100 cutaway. Referring to FIG. 3, the body 108 may also include a core tube 132 inward from the inner layer 120. The outer layer 110 and the inner layer 120 may surround the core tube 132. The core tube 132 may adjoin the inner layer 120. The core tube 132 may be integral to the inner layer 120. The core tube 132 and the inner layer 120 may be bonded or otherwise joined together. The core tube 132 may form an inner sleeve of the grip 100 for the shaft 50 and may be formed to include the elongated cavity 109. In some embodiments, the core tube 132 and the outer layer 110 may be in contact adjacent to the open end 103. The cap 102, the core tube 132, and the outer layer 110 may enclose a volume that is filled by the inner layer 120. The core tube 132 may include a right circular cylinder shape.

The core tube 132 may include one or more layers of elastomeric materials, such as rubber, polyurethane, or thermoplastic elastomer. In some embodiments, the core tube 132 can include shock absorbing properties.

The core tube 132 and the cap 102 may be integral, such as bonded together, glued together, or molded as a unitary piece.

The outer layer 110 includes an outer layer end 113 which may not extend completely to the open end 103. The core tube 132 may extend to the outer layer end 113 and may extend beyond the outer layer end 113 to form a tip 104 that includes the open end 103 as illustrated in FIGS. 3 and 4. The tip 104 may be formed of an elastomeric material. The tip end 104 can also be formed of the same material as the outer layer 110 or the inner layer 120, as needed.

FIG. 4 is a perspective view of a further embodiment of the grip 100 of FIG. 1 with a portion of the grip 100 cutaway. Referring to FIG. 4, the body 108 may also include core protrusions 134. The core protrusions 134 may extend from the core tube 132 to the outer layer 110 through the inner layer 120. The core protrusions 134 may be interspersed throughout the inner layer 120.

The core protrusions 134 may be full or partial ribs extending around the circumference of the core tube 132, along the axis of the core tube 132 and along the elongated cavity axis 90, or may spiral about the core tube 132. The core protrusions 134 that are full ribs may subdivide the volume enclosed by the cap 102, the core tube 132 and the outer layer 110, and may subdivide the inner layer 120 into foam layer sections 122. The core protrusions 134 may also be spokes, such as partial ribs that extend partially around the circumference of the core tube 132 or tubes that extend outward from the core tube 132 to the outer layer 110.

The core protrusions 134 and the core tube 132 are integral and may be joined or molded as a unitary piece as shown in FIG. 5. The core protrusions 134 may be formed of the same or similar materials as the core tube 132. The core protrusions 134 may include elastomeric materials, such as rubber, polyurethane, or thermoplastic elastomer, and can include shock absorbing properties.

FIG. 5 is a cross-section of a portion of an embodiment of the grip 100 of FIG. 1. The grip 100 may also include a surface coating 140 on the outer surface 111 of the outer layer 110. The surface coating 140 may improve the durability or the gripping properties of the grip 100. These properties include inter alia, an increased coefficient of friction at the outer surface 111, increased surface tack, and increased surface hardness. The surface coating 140 may include, inter alia, polyurethane coatings and rubber based coatings.

FIG. 6 is a perspective view of the grip of FIG. 1 illustrating a texture layer 114 adjacent to the grip 100. The texture layer 114 may be an overlay or an inlay. The texture layer 114 may be located within the composite material, inward of the composite material or outward from the composite material. During the manufacturing process, the texture layer 114 may be located between layers, such as sheets, of the reinforcement material prior to adding the binding matrix, located under the layers prior to adding the binding matrix, or may be located on the composite material after adding the binding matrix. The texture layer 114 may include tactile features 115, alignment features 116, and graphic features 117. The tactile features 115 may be protrusions, depressions, or a combination thereof. The alignment features 116 may also be protrusions, depressions or graphic in nature, and may be located adjacent the closed end 101 or the open end 103. Graphic features 117 may be, inter alia, images, logos, symbols, or a combination thereof.

FIG. 7 is a perspective view of another embodiment of the grip of FIG. 1 with a portion of the grip cutaway. FIG. 8 is a detailed view of the portion of FIG. 7 enclosed by rectangle VIII in FIG. 7. A portion of the surface coating 140 in FIG. 8 is cutaway and not shown for illustrative purposes. In the embodiment illustrated in FIGS. 7 and 8, the texture layer 114 is located outward of the outer layer and may be a decal that is adhered to the outside of the outer layer 110. In general, the texture layer 114 may be applied on embodiments of the grip 100 having a composite, or shell as the outer layer 110. The texture layer 114 may be a continuous strip of material as illustrated, may be multiple strips of material that include tactile features 115, or may be individual tactile features 115.

In the embodiment illustrated, the surface coating 140 is located outward of the texture layer 114, with the texture layer 114 located between the outer layer 110 and the surface coating 140. In other embodiments, the texture layer 114 may be decals that are applied after the surface coating 140. The tactile features 115 may form some or all of the surface texture 112 of the grip 100.

The grip 100 as described herein may have a high modulus hybrid construction. The outer layer 110 may have a seamless construction and may not deflect inward when gripped, which can allow a golfer to grasp the grip comfortably and precisely no matter the gripping method the golfer uses. The outer layer 110 may also improve the durability of the grip 100.

The layered construction of the embodiments of the grip 100 described herein may allow for the fine tuning of the weight of the grip 100, such as by adjusting the thickness of each layer and by the foam density. The layered construction also allows for the fine tuning of the amount of vibration that reaches the golfer's hand. Dampening some of the vibration may filter the noise and allow proper vibrational feedback to reach the golfer's hand. This feedback may help the golfer feel how hard the ball was struck and where on the clubface the ball was struck, which may provide the golfer valuable information about the golfer's putting stroke.

The vibrational dampening and transference of vibration from the shaft 50 to a hard, or composite shell outer layer 110 may be tuned by, inter alia, the thickness of the core tube 132 and the amount of contact that the outer layer 110 has with the core tube 132, the core protrusions 134, and with the cap 102. While the core protrusions 134 may have some dampening properties, those properties may be less than the dampening properties of the inner layer 120. Thus, the amount vibrational transference to the outer layer 110 may be controlled by the pattern, shapes, and thicknesses of the core protrusions 134 and the contact area the core protrusions 134, the core tube 132, and the cap 102 each have with the outer layer 110.

Additional Matters

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. The described embodiments are not limited to use in conjunction with a particular type of golf club. Hence, although the present disclosure, for convenience of explanation, depicts and describes particular embodiments of the grip for a putter, it will be appreciated that the grip in accordance with this disclosure can be used with various other types of golf clubs, and can be used with other types of implements. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles described herein can be applied to other embodiments without departing from the spirit or scope of the invention. Thus, any explanation in connection with one embodiment applies to similar features of other embodiments, and elements of multiple embodiments can be combined to form other embodiments. It is to be understood that the description and drawings presented herein represent a presently preferred embodiment of the invention and are therefore representative of the subject matter which is broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other embodiments that may become obvious to those skilled in the art.

COMPOSITE GOLF CLUB GRIP WITH FOAM LAYER

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