Abstract:
A method of customizing a golf club head for a user&#39;s swing begins by receiving an indication of a characteristic of a user&#39;s golf swing. A club face is selected from a plurality of club faces based on the characteristic, and a club body is selected from a plurality of club bodies based on the characteristic. The selected club face and club body are then affixed together to define a golf club head. Each of the plurality of club faces and plurality of club bodies are freely interchangeable.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present invention is a continuation of U.S. patent application Ser. No. 14/709,964, filed on May 12, 2015, which is incorporated by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates generally to a method of providing a customizable golf club head. 
       BACKGROUND 
       [0003]    A golf club may generally include a club head disposed on the end of an elongate shaft. During play, the club head may be swung into contact with a stationary ball located on the ground in an effort to project the ball in an intended direction and with a desired vertical trajectory. 
         [0004]    Many design parameters must be considered when forming a golf club head. For example, the design must provide enough structural resilience to withstand repeated impact forces between the club and the ball, as well as between the club and the ground. The club head must conform to maximum size requirements set by different rule setting associations, and the face of the club must not have a coefficient of restitution above a predefined maximum (measured according to applicable standards). Assuming that certain predefined design constraints are satisfied, a club head design is typically quantified by the magnitude and location of the center of gravity, as well as the head&#39;s moment of inertia about the center of gravity and/or the shaft. 
         [0005]    The club&#39;s moment of inertia relates to the club&#39;s resistance to rotation (particularly during an off-center hit), and is often perceived as the club&#39;s measure of “forgiveness.” In typical driver designs, high moments of inertia are desired to reduce the club&#39;s tendency to push or fade a ball. Achieving a high moment of inertia generally involves placing mass as close to the perimeter of the club as possible (to maximize the moment of inertia about the center of gravity), and as close to the toe as possible (to maximize the moment of inertia about the shaft). 
         [0006]    While the moment of inertia affects the forgiveness of a club head, the location of the center of gravity behind the club face (and above the sole) generally affects the trajectory of a shot for a given face loft angle. A center of gravity that is positioned as far rearward (away from the face) and as low (close to the sole) as possible typically results in a ball flight that has a higher trajectory than a club head with a center of gravity placed more forward and/or higher. 
         [0007]    While a high moment of inertia is obtained by increasing the perimeter weighting of the club head, an increase in the total mass/swing weight of the club head (i.e., the magnitude of the center of gravity) has a strong, negative effect on club head speed and hitting distance. Said another way, to maximize club head speed (and hitting distance), a lower total mass is desired; however a lower total mass generally reduces the club head&#39;s moment of inertia (and forgiveness). 
         [0008]    In the tension between swing speed (mass) and forgiveness (moment of inertia), it may be desirable to place varying amounts of mass in specific locations throughout the club head to tailor a club&#39;s performance to a particular golfer or ability level. In this manner, the total club head mass may generally be categorized into two categories: structural mass and discretionary mass. 
         [0009]    Structural mass generally refers to the mass of the materials that are required to provide the club head with the structural resilience needed to withstand repeated impacts. Structural mass is highly design-dependant, and provides a designer with a relatively low amount of control over specific mass distribution. On the other hand, discretionary mass is any additional mass that may be added to the club head design for the sole purpose of customizing the performance and/or forgiveness of the club. In an ideal club design, the amount of structural mass would be minimized (without sacrificing resiliency) to provide a designer with a greater ability to customize club performance, while maintaining a swing weight that is expected by the consumer. 
       SUMMARY 
       [0010]    A method of customizing a golf club head for a user&#39;s swing begins by receiving an indication of a characteristic of a user&#39;s golf swing. A club face is selected from a plurality of club faces based on the characteristic, and a club body is selected from a plurality of club bodies based on the characteristic. The selected club face and club body are then affixed together to define a golf club head. Each of the plurality of club faces and plurality of club bodies are freely interchangeable. 
         [0011]    Each club face may be formed of metal and has a parameter that is different than the same parameter for every other club face in the plurality of club faces. This variable parameter may be one of: loft angle; face angle; bulge radius; roll radius; mass; audible impact frequency; thickness; and coefficient of restitution. Furthermore, each club body may be primarily formed from a polymer and has a weight parameter that is different than the same weight parameter for every other club body in the plurality of club bodies. The variable weight parameter may be one of: total mass; and mass distribution. 
         [0012]    In some embodiments, a kit of parts may be provided for assembling a golf club head with customized attributes. The kit includes a plurality of club faces, a plurality of club bodies, and a plurality of mechanical fasteners. Each club face of the plurality of club faces is formed of metal and has a parameter that is different than the same parameter for every other club face in the plurality of club faces. The parameter may be one of: loft angle; face angle; bulge radius; roll radius; mass; audible impact frequency; thickness; and coefficient of restitution. Each club body of the plurality of club bodies is primarily formed from a polymer and has a weight parameter that is different than the same weight parameter for every other club body in the plurality of club bodies. The weight parameter being one of: total mass; and mass distribution. Finally each mechanical fastener is adapted to extend through a respective opening in a selected club face and into a selected club body to provide an assembled golf club head. 
         [0013]    The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a schematic front view of a golf club having a detachable face. 
           [0015]      FIG. 2  is a schematic exploded view of the golf club head of  FIG. 1 . 
           [0016]      FIG. 3  is a schematic cross sectional view of the golf club head of  FIG. 1 , taken along line  3 - 3 . 
           [0017]      FIG. 4  is a schematic cross sectional view of the golf club head of  FIG. 1 , taken along line  3 - 3  and in an opposite direction from  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    Referring to the drawings, wherein like reference numerals are used to identify like or identical components in the various views,  FIG. 1  illustrates a schematic perspective view of a wood-type golf club head  10  (i.e., “club head  10 ”) that generally includes a face portion  12  (i.e., the “face  12 ”) and a body portion  14  (i.e., the “body  14 ”). As generally illustrated in  FIG. 2 , the club head  10  may be mounted on the end of an elongate shaft  16 , which may be gripped and swung by a user to impart a generally arcuate motion to the club head  10 . 
         [0019]    The face  12  of the club head  10  may generally include a ball-striking portion  18  having a hitting surface  20  that is intended to contact a golf ball during a normal swing. The hitting surface  20  may be a planar surface, or may have a slight convex/arcuate curvature (i.e. bulge and/or roll) that extends out from the club head  10 . Additionally, as is commonly understood, the hitting surface  20  may be disposed at an angle to a vertical plane when the club is held in a neutral hitting position. This angle may be generally referred to as the loft angle or slope of the club. Wood-type club heads (including hybrid woods), such as illustrated in  FIGS. 1-4 , may most commonly have a loft angle of from about 8.5 degrees to about 24 degrees, though other loft angles are possible and have been commercially sold. 
         [0020]    The body  14  of the club head  10  may generally be configured to support the face  12  and to provide a connection means between the face  12  and the elongate shaft  16 . Referring again to  FIG. 1 , the body  14  may generally include a lower portion  22  (i.e., a “sole  22 ”) and an upper portion  24  (i.e., a “crown  24 ”). For the purpose of this description, the crown  24  may meet the sole  22  where the surface has a vertical tangent when the club head  10  is held in a neutral hitting position (i.e., a position where the shaft  16  is maintained entirely in a vertical plane and at a prescribed lie angle relative to a horizontal ground plane). In practice, a portion of the sole  22  near this transition point may also be referred to as the skirt  26 . Finally, the club head  10  includes a hosel  28  that is configured to receive a shaft adapter and/or otherwise couple with the elongate shaft  16 . 
       Detachable Cup Face 
       [0021]    In one embodiment, the face  12  may have a cup-face style construction/design that includes a side-wall portion  38  extending from the perimeter of the ball-striking portion  18  toward the rear of the club head  10 . The side-wall portion  38  and the ball-striking portion  18  may form a concave recess opposite the hitting surface  20  (i.e., having a cup-like appearance). Such a face construction enables the attachment point between the face  12  and the body  14  to be positioned behind the hitting surface  20 . This is in contrast to other plate-like face constructions that require attachment at or around the perimeter of the hitting surface  20 , itself. By positioning the attachment apart from the hitting surface, it is less likely that any attachment means (e.g., a weld, screw, or the like) would influence the flexural properties of the hitting surface  20 . Conversely, in plate-like face constructions, weld beads and/or thermal tempering may directly affect the stiffness of the perimeter of the hitting surface  20 . 
         [0022]    Additionally, the face  12  may be formed from a material that may suitably withstand a direct impact with a golf ball. While such a material may preferably be metallic, such as a titanium alloy, in other embodiments, it may include one or more polymer layers, carbon-fiber layups, or the like. In still other embodiments, the face  12  may be entirely formed from a polymeric material that is designed to withstand large impact loads. 
         [0023]      FIG. 3  generally illustrates a schematic cross-sectional view  40  taken along section  3 - 3  shown in  FIG. 1 . As shown, the face  12  and the body  14  may cooperate to surround and/or define an internal volume/cavity  44 . Additionally, the cup face  12  may be dimensioned to allow a portion of the body  14  to be received and selectively secured within the concave recess formed by the cup face  12 . In one configuration, the face  12  may be secured to the body  14  via one or more mechanical fasteners  46  that extend through the sidewall  38  and into the body  14 . The mechanical fasteners  46  may include one or more screws, cams, or other such devices that may restrain the face  12  from being removed from the body  14  while in place, though may provide a non-destructive means of separating the face  12  and the body  14  when removed. 
         [0024]    Enabling removal of the face  12  may provide certain benefits that are not found in conventional fixed face designs. For example, interchangeable faces may be used to selectively vary at least one geometric face parameter such as, for example, the face angle, the loft angle, the bulge radius, or the roll radius. Likewise, interchangeable faces may also be used to selectively vary at least one dynamic response parameter such as, for example, the club head center of gravity, the total mass of the club head, or the coefficient of restitution of the face. Finally, interchangeable faces may also be used to alleviate durability concerns that may result from certain thin face designs. 
         [0025]    With regard to altering at least one geometric face parameter of the club head  10 , different users may benefit from differing face geometries according to their swing characteristics. For example, a user that has a tendency to slice their drive, may benefit from a face angle that has a draw bias. Likewise, a user with a slow swing speed may benefit from a greater loft angle than a user with a fast swing speed. Finally, a user that has a tendency to impact the ball away from the center of the face may benefit from a clubface that has an increased bulge radius or roll radius. 
         [0026]    While the geometric face parameters may relate to the specific geometry of the club face  12 , the dynamic response parameters may affect the behavior of the club head  10  throughout the swing and impact. Different faces may be specifically designed to alter the location of the center of gravity of the club head  10  or alter various moments of inertia of the club head. This may be accomplished by changing the distribution of weight between the heel and toe, between the crown and sole and/or around the perimeter of the hitting surface  20 . For example, placing additional mass toward the outer perimeter of the club head  10  and/or toward the toe may increase the club head&#39;s moment of inertia (resistance to twisting). Likewise, placing additional weight toward the sole may lower the club head&#39;s center of gravity, which generally increases launch angle and spin. Additionally, by enabling removal of the face  12 , weights may be selectively placed within the body, such as by affixing to a predetermined weight port. 
         [0027]    Finally, from a durability perspective, a removable face may allow thinner hitting surfaces to be used without as much concern for the long term durability of the club head  10 . The durability of a face  10  is typically measured by successively impacting the face with a predetermined number of golf balls traveling at a high rate of speed. The test is often performed at various locations across the club head  10 , and the club head must not show any signs of structural damage following a test. In fixed face designs, the club face is often overdesigned and/or made significantly thicker to pass such a durability test at professional tour-level swing speeds. By providing a means to replace a damaged face, the durability standards may be reduced to permit thinner face designs. Alternatively, faces may be provided to more closely correlate with the end user&#39;s actual swing speed rather than always overdesigning the face to satisfy tour-level conditions. 
       Polymeric Body 
       [0028]    To reduce structural mass beyond what is economically viable with metal alloys, the body  14  of the club head  10  may be formed from a polymeric material, which is less dense than traditional metal body designs. To promote design flexibility, the polymeric material may be molded into shape using any of the number of molding techniques, such as, injection molding, compression molding, blow molding, or the like. While weight savings and design flexibility are important, the polymeric material must also be strong enough to withstand the stress that is experienced when the club head  10  impacts a ball. To accomplish this, it is preferable to use a material that has a tensile strength of greater than about 200 MPa (according to ASTM D638), or more preferably greater than about 250 MPa. Additionally, for ease of molding, if the polymeric material is filled, then it desirably has a resin content of greater than about 50%, or even greater than about 55% by weight. One such material may include, for example, a thermoplastic aliphatic or semi-aromatic polyamide that is filled with chopped fiber, such as chopped carbon fiber or chopped glass fiber. Other materials may include polyimides, polyamide-imides, polyetheretherketones (PEEK), polycarbonates, engineering polyurethanes, and/or other similar materials. In one configuration, the polymeric body  14  may be devoid of any metallic support structure or frame that directly couples with the face  12 . 
         [0029]    In one configuration, the polymeric body  14  may be integrally formed as a single, continuous piece. An integral design may have strength benefits by reducing seams, weld lines, or other parting lines, however it may also increase the complexity of the molding process. In other configurations, the body  14  may be formed from multiple components that are fused together through, for example, ultrasonic welding, laser welding, or the use of adhesives. For example, in one embodiment, the sole  22 , crown  24 , and hosel  28  may each be formed through a separate molding process and then subsequently fused together. 
         [0030]    As noted above, and shown in the figures, the hosel  28  may be formed from a polymeric material, similar to the crown  24  and the sole  22 . Referring to  FIG. 1 , the hosel  28  generally defines a recess  60  that is configured to receive a golf club shaft  16  and/or a shaft adapter  62 . In one configuration, the hosel  28  includes a plurality of splines  64  disposed on an inward-facing surface that surrounds the recess  60 . The splines  64  are intended to inhibit any relative rotation between the shaft  16  and the golf club head  10  once the shaft  16  or shaft adapter  62  is inserted within the recess  60 . 
         [0031]    In one configuration, the hosel  28  may be formed through similar molding techniques as the remainder of the body, and using similar polymeric materials. When formed in this manner, the hosel  28  may avoid any need for metallic inserts to be secured within the recess  60 . More specifically, by having flexural characteristics that more closely match those of the shaft adapter  62  and or certain composite shafts, boundary layer incompatibilities may be minimized, which reduces wear at the interface and increases durability. 
         [0032]    In general, the body  14  of the present design accomplishes four objectives: supporting the face  12 ; structurally coupling the face  12  with the shaft via the hosel  28 ; moving the center of gravity of the club head  10  rearward of the face  12  and/or hitting surface  20 ; and, increasing the moment of inertia of the club head  10  to allow the club head  10  to strike through the ball and minimize any twisting. A polymer body construction may accomplish the first two objectives at a lower required structural weight than conventional metal body construction. In doing so, the polymer body construction may provide a greater amount of discretionary weight that can be strategically placed about the club head (to better accomplish the last two objectives). 
         [0033]    In one configuration, to secure the face  12  to the body  14 , each of the plurality of mechanical fasteners  46  may be either directly received by the polymer, or may be received by an inlaid object, such as a metal insert. The mechanical fasteners  46  may be directly received, for example, by providing a threaded recess directly in the polymer. If inserts are used, then each insert may have, for example, a threaded internal section that receives one fastener. In one configuration, each insert may be separately placed in the body such that the polymeric material surrounds each insert separately and/or such that the inserts are coupled to each other only via the polymer. 
         [0034]    For weighting purposes, the polymer body  14  may include one or more discretionary weights, such as captured metallic inserts, that may be used to alter the magnitude and/or position of the club head center of mass and/or one or more moments of inertia of the club head  10 . These discretionary weights are located apart from the face  12  and coupled to the face  12  via the polymeric material. In one configuration, the discretionary weights are separated from the face  12  by a minimum distance that is, for example, greater than about 10 mm. In one embodiment, as shown in  FIG. 3 , the discretionary weight may include a metallic band  70  that is disposed about a portion of the perimeter of the club head  10  (e.g., where the sole  22  meets the crown  24 ). Such a weight may increase the moment of inertia about a vertical axis, and may move the center of mass rearward of the face. In one embodiment, this band  70  may have a varying thickness to enable more precise control over the location of the center of gravity and the various moments of inertia. In other embodiments, the discretionary weight may include a doped portion of the polymeric body  14 , a weighted medallion that is adhered to the inside or outside of the body  14 , or a screw-in or twist-lock removable weight. 
         [0035]    In still other configurations, the metallic inserts may include one or more metal objects, such as plates or discs that are overmolded by the polymer within the sole  22 , crown  24 , intersitital space, or other portions of the body  14 . Due to the cost effective nature of polymer molding, a manufacturer may use these techniques to produce a plurality of club head bodies that each have a different mass and/or mass distribution. In still other configurations, the metallic inserts may have a threaded portion that can receive a screw-in style weight. 
       Club Customization 
       [0036]    Using the present design, a club head may be assembled in a manner that is specific to the characteristics of a user&#39;s swing. More specifically, constructing a club head may include the steps of: selecting a face  12  from a plurality of faces, each of the plurality of faces having one or more different parameters selected from the loft angle, the face angle, the bulge radius, the roll radius, the mass, the audible impact frequency, and the coefficient of restitution across the club face; selecting a body  14  from a plurality of bodies, each of the plurality of bodies having a different weight parameter selected from a total mass and a mass distribution. 
         [0037]    In one configuration, for example, the plurality of faces may include at least three different faces, each having a different coefficient of restitution intended for a user with a different swing speed (e.g., slow, average, fast). In another configuration, the plurality of faces may include at least nine different faces, with each face having one of three different coefficient of restitutions and one of three different face orientation profiles (e.g., low, medium, and high loft, or draw, neutral, fade biased face angle). 
         [0038]    In a similar manner, in one configuration, the plurality of bodies may include at least three bodies, each having a different total mass intended for users of differing swing speeds (e.g., light, average, and heavy bodies, intended for users of slow, average, and fast swing speeds, respectively). In another configuration, the plurality of bodies may include at least nine different bodies, with each body having one of three different total masses and one of three different weight biasing profiles (e.g, toe, center, and heal-biased weighting; or face, mid, and rear-biased weighting). 
         [0039]    In another embodiment, a shaft adapter such as described in U.S. Patent Application No 2013/0324291 to Arluna et al, which is incorporated by reference in its entirety, may be used to vary the loft angle and face angle, while the plurality of faces may be used to vary the coefficient of restitution, and the plurality of bodies may be used to vary the total club head mass and/or one or more dynamic parameters such as a dynamic loft or a ball-spin tendency. 
         [0040]    In addition to providing different weight profiles, the cosmetic appearance may also be more substantially varied through the polymer body construction. In general, polymer molding techniques can provide a more complex and detailed design than metal fabrication techniques are capable of. Additionally, for a similar design, polymer molding is generally less expensive than metal fabrication. As such, the plurality of bodies may also include varying cosmetic designs that range from conservative (i.e., a generally uniform shell) to aggressive (i.e., including many recesses, accent ribs, or colored panels). 
         [0041]    By permitting a mix and match style of club head creation, retailers may be able to offer a more customized golf club that is tailored specifically to a user&#39;s preferences or swing. This interchangeable component structure also can eliminate the need to inventory every possible combination of components. 
         [0042]    While various embodiments have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims. 
         [0043]    “A,” “an,” “the,” “at least one,” and “one or more” are used interchangeably to indicate that at least one of the item 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, 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; about 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, disclosure of ranges includes disclosure of all values and further divided ranges within the entire range. Each value within a range and the endpoints of a range are hereby all disclosed as separate embodiment. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated items, but do not preclude the presence of other items. As used in this specification, the term “or” includes any and all combinations of one or more of the listed items. When the terms first, second, third, etc. are used to differentiate various items from each other, these designations are merely for convenience and do not limit the items.