Abstract:
A golf club having superior balance and sensory feedback which includes a shaft connected to a clubhead comprising two basic elements, an integrated hosel and insert which defines a striking surface and a shell including a distal toe portion, and a heel portion uniquely integrated with the combined hosel and insert. In preferred embodiments the clubhead has a cylindrical striking surface, polar mass concentrations for optimum dynamic performance and a medial shell portion coupling the toe and heel portions to the insert. A cavity behind the striking surface of the insert enhances the sound of impact and a visible top surface of the insert integral with the hosel with sighting indicia enhances golfer alignment and stroking of the ball to provide resultant confidence and consistency.

Description:
REFERENCE TO RELATED PATENT APPLICATION 
   This patent application claims the benefit of U.S. Provisional Patent Application No. 60/148,011 filed Aug. 10, 1999. 

   TECHNICAL FIELD OF THE INVENTION 
   The present invention relates to the field of golf clubs, and more particularly, to the field of golf putters. 
   BACKGROUND OF THE INVENTION 
   The prior art has provided numerous golf clubs, and particularly, golf putters, that are designed to improve the performance of the golfer or otherwise enhance the golfing experience. For example, U.S. Pat. No. 3,042,405 to Karsten Solheim discloses a golf club having internal weights at the heel and toe ends of the club with two thin plates connecting them. The sound of the club as it strikes a golf ball at the center of the club face is described as different from the sound made by the golf club when striking the golf ball at an off-center position. It is stated that the substantially hollow center behind the front face of the club provides an audible indication when the golfer has struck the golf ball at the optimum central portion of the club. U.S. Pat. No. 4,444,395 to Morton Reiss shows a golf putter head having a low mass center section and two more massive end sections. The sections have substantially the same transverse cross section forming a single continuous cylinder. A major portion of the mass is in the end portions which are connected together longitudinally to the center section by two steel pins. The club shaft is secured to the head centrally in the center section. More recently, U.S. Pat. No. 5,090,698, issued to Thomas A. Kleinfelter, and discloses a golf putter having a clubhead with a striking face suspended between two flanges near the toe and heel. This is said to provide a center of percussion extending along essentially the entire length of the clubhead to thereby provide an optimum strike against the ball even if the ball contact is off center. Numerous other golf clubs have been provided in the prior art described by the designers as enhancements of sound, balance, or human factor considerations. 
   Some golf clubs known in the art are said to have a substantially awkward “feel” when striking a golf ball, believed to be in part because of the distribution of weight within the clubhead. In addition, while the prior art has provided other golf clubs that are said to have a proper feel and to be properly balanced, many of these golf clubs are unattractive and the physical appearance is distractive. Those configurations do not provide the optimum perspective to the golfer as the ball is addressed or audible response as the club strikes the ball. There thus exists a need in the art for a golf club that has an optimum feel and sound, an appearance which supports concentration and a sighting perspective and audible response that optimize the relationship between golfer and putter. It is a general object of the invention to provide a club that satisfies the foregoing criteria. 
   Specifically, the general objects of the invention include the creation of a golf club, especially a putter, that provides sensitive feed-back to the golfer for improved performance. The golfer, golf club and golf ball are connected during the swing and at impact to provide superior sensitivity to the action, a dynamic sense of balance and an enhanced “feel” which is fed back to the hands indicative of stroke quality. This is augmented by the enhanced visual perception or “sighting” provided. The improved characteristics are believed to result from the integrated nature of the hosel and an insert which includes the striking surface, augmented by the other features of the invention described and claimed. 
   SUMMARY OF THE INVENTION 
   The present invention provides a well-balanced golf club that satisfies the foregoing general objects. The golf club of the invention includes a shaft that has a handle end and a clubhead end. The clubhead end is connected to a clubhead comprising two basic elements. The two basic clubhead elements are (1) a combined hosel and insert defining a striking surface integrally related to a sighting surface and to the shaft and handle, and (2) a shell including a distal toe portion and a heel portion, each secured to the insert. Where the shaft and the insert are of the same material they may be formed as a single unit. In a preferred embodiment, a medial portion is secured between the heel and toe portions configured for optimum dynamic balance, sensitive feed-back and related enhanced sighting. The combined insert and hosel are preferably of low mass density materials compared to the shell to provide an optimum polar mass distribution. The insert is visible on a top surface which will assist the golfer in addressing the ball and aligning the club and ball for the putt. Top surface treatment in a preferred embodiment can further enhance the sighting. 
   In preferred embodiments of the invention, the clubhead insert has a striking surface having a cylindrical configuration and preferably a cylindrical configuration the longitudinal axis of which is aligned with the longitudinal axis of the clubhead. In some preferred embodiments, a space is provided behind the striking surface to provide an audible response indicative to the golfer of stroke quality. 
   Also, in preferred embodiments of the invention, high mass density elements are added to the toe portion and the heel portion of the shell to improve the optimum balance and dynamic characteristics of the putter. In various preferred embodiments of the invention, the insert can have a front plate defining the striking surface integral with the hosel and secured to the toe, heel and medial portions of the shell or it may have various configurations including a longitudinal channel shape or comprise a longitudinal cylindrical tube extending from a base or root in the heel. In still other preferred embodiments, the combined hosel and insert includes a reinforcing armature connecting the hosel and insert and the insert is a generally rectilinear blade having an exposed striking surface, sole surface and sighting top surface. Furthermore, the hosel includes an offset portion to generally align the shaft axis with the striking surface. 
   Other features and objects of the invention will be apparent from the following description of the invention. 

   
     DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an overview perspective of one embodiment of the invention; 
       FIG. 2   a  is a perspective view of the clubhead of the embodiment of the invention shown in  FIG. 1 ; 
       FIG. 2   b  is a top view of the embodiment of  FIG. 2   a;    
       FIG. 2   c  is a bottom view of the embodiment of  FIG. 2   a , and 
       FIGS. 2   d  and  2   e  are sectional views taken along the lines  2   d  and  2   e  of  FIG. 2   b;    
       FIGS. 3   a - 3   e  are, respectively, a perspective view, a top view, a bottom view and sectional views of another embodiment of the invention; 
       FIGS. 4   a - 4   e  are, respectively, a perspective view, a top view, a bottom view, and sectional views of the clubhead of an additional embodiment of the invention; 
       FIGS. 5   a - 5   c  are, respectively, a perspective view, a rear view and a sectional view of still another clubhead embodying the invention; 
       FIGS. 6   a - 6   c  are, respectively, a perspective view, a rear view and a sectional view of a clubhead forming a part of another embodiment of the invention; 
       FIGS. 7   a - 7   c  are, respectively, a perspective view, a rear view and a sectional view of another golf club incorporating the invention; 
       FIGS. 8   a - 8   c  are, respectively, a perspective view, a rear view and a sectional view of the clubhead portion of still another embodiment of the invention; 
       FIGS. 9   a - 9   e  are directed to a preferred embodiment of the invention and are, respectively, a perspective view, a rear view, a cross sectional view, a partially sectional and partially exploded view and a sectional view along the line  9   e — 9   e  of  FIG. 9   d;    
       FIG. 9   f  is a partially sectional view of an alternate preferred embodiment of the invention taken at lines  9   c - 9   c  of  FIG. 9   b  showing the insert, hosel and shaft formed as a single piece; and 
       FIGS. 10   a - 10   d  are, respectively, a perspective view, a rearview and sectional views of an additional preferred embodiment of the clubhead portion of the invention including added mass elements in the toe and heel sections. 
   

   DESCRIPTION OF THE INVENTION 
   The invention provides a golf club which may constitute any one of a set of golf clubs designed for the game of golf including, for example, a driver, a fairway “wood” or “iron” or other club. Preferably, however, the golf club of the invention is in the form of a putter and is thus designed to facilitate controlled golfer action in striking a golf ball on a relatively smooth playing surface to cause the golf ball to roll toward its intended target and not to impart loft to the ball. With reference to  FIG. 1 , the golf club  10  has a clubshaft  11  which may be fabricated from graphite, metal or other conventional materials. At the golfer gripping end  12  of shaft  11 , an overlying grip  13  is provided which may be leather, and may have any conventional surface treatment. Opposite the gripping end  12 , the shaft  11  has a clubhead end  14  which is mounted to a clubhead  15 . 
   The clubhead  15  comprises two basic components, a combined insert and hosel  16  and a shell  18 . The shell  18  includes a heel portion  20 , a toe portion  22 , and a medial portion  24 . In the embodiments of  FIG. 1 , the shell also includes a sole portion  26 . The hosel includes a central portion that provides an offset whereby the shaft is aligned with the striking surface. 
   In the embodiment shown in  FIG. 1 , the insert  21  has a cylindrical-type striking surface  28  which conforms to similar cylindrical-type striking surfaces  30  and  32  on the shell  18 . The striking surfaces  28 ,  30  and  32  align to define a clubhead striking face. In the preferred embodiment, the striking face comprises a segment of a right circular cylinder, the directrix of which aligns with the longitudinal axis of the clubhead. In one preferred embodiment, that directrix is slightly above the longitudinal central axis of the clubhead. Thereby, when the clubhead strikes a golf ball with an optimum stroke, it imparts a slight negative loft to the ball. 
   Referring now to the more detailed Figures of the drawings,  FIGS. 2   a - 2   e  illustrate in greater detail the embodiment of FIG.  1 . The shaft  11  and grip  13  of  FIG. 1  are omitted in  FIGS. 2   a-e , the shaft portion  40  of the hosel  17  have been partially broken away and a fairing  34  is disposed between the upright portion  36  of the hosel  17  and the top sighting surface  19  of insert  21 . As shown in  FIG. 2   a , the hosel portion  17  of the combined insert and hosel  16  may include the upright portion  36 , an angular portion  38 , and the shaft portion  40 . In the preferred embodiment, the central axes of the angular portion  38  of hosel  17  forms a small acute angle with the striking surface and with the shaft. The offset aligns the shaft with the striking surface. In the embodiment of  FIG. 2 , the bottoms of heel portion  20 , toe portion  22 , sole portion  26  and medial portion  24  comprise the sole or sole plate  25  of the club as shown in  FIG. 2   c . Also, in the embodiment of FIG.  2  and in other preferred embodiments, the sole  25 , whether made up entirely of portions of shell  18  or not has a curvature along the longitudinal axis of the clubhead  15  with the central portion of the striking surface  28  of insert  21  being disposed at the optimum striking point or “sweet spot” both longitudinally and vertically. 
   In the embodiment of  FIGS. 2   a-e , the combined insert and hosel  16  includes a base portion  42  underlying the hosel  17  and the insert extends longitudinally along the clubhead therefrom in the form of a rectangular tube including a top wall  43  defining the sighting surface  19 , a striking side wall  44 , a vertical back wall  46  spaced from striking wall  44  and a bottom wall  48  parallel to and spaced from the top wall  19  to define a cavity  50 . It has been found that providing the cavity  50  enhances the sound upon impact of the clubhead with the ball producing a positive clicking sound. That sound varies with the point of impact of the ball and club both vertically and along the longitudinal axis of the clubhead. The combined insert and hosel  16  is preferably formed of a non-metallic and usually a composite material such as a graphite composite or a fiberglass and resin composite. It is desirable that the mass density of the combined insert and hosel  16  be less than the mass density of the shell to provide polar weighting of the clubhead and resulting enhanced dynamic performance of the club. 
   Referring now to  FIGS. 3   a-e , another preferred clubhead embodiment  115  of the invention is shown in which the combined hosel and insert  116  differs in several significant respects from the corresponding part  16  of FIG.  2 . The hosel  117  is of a known type with sharp, transverse offset  138  designed to displace the shaft end  140  toward alignment with the striking surface  128 . The clubhead portion  136  of the hosel  117  is integral with the insert  121  and extends from the top wall  143  of insert  121 . 
   It has been found that the visibility of at least a significant portion of the top insert surface  119  and fairing  134  provides the golfer with a feeling of an integrated grip and striking surface through the connection of the clubhead portion  136  of the hosel  117  with the top sighting surface  119  through the fairing  134 . In addition to the heel portion  120  and toe portion  122  of the shell  118 , the shell has a top portion  152  forming a part of medial portion  124  extending toward the striking surface  128 . In the embodiment of  FIGS. 3   a-e , the bottom wall  148  of insert  121  forms part of sole plate  125  and the medial shell portion  124  defines the backwall for cavity  150 . 
   Referring now to  FIGS. 4   a-e , the clubhead  215  comprises the combined insert and hosel  216  and the shell  218 . In the embodiment of  FIG. 4  the insert  221  extends the full height of the striking face  223  and has a cylindrical striking surface  228  parallel to the longitudinal axis of the club as already described above with respect to  FIGS. 2   a - 2   e . As shown in  FIGS. 4   a  and  4   e , especially, the curved surface is a segment of a right circular cylinder with the directrix rearwardly thereof and slightly above the center of the clubhead to impart a slight negative loft upon impact with the ball. In this embodiment as shown in  FIG. 4   b , the top surface  219  of the insert  221  is fully visible and the fairing  234  connecting the insert  221  and the hosel  217  is directly viewable by the golfer as he addresses the ball. As the striking or forward surface  228  extends the full height of the clubhead, the bottom wall  248  of insert  219  comprises the sole of the club. The top wall  243  combines with the bottom wall  248  and striking wall  244  to define the cavity  250  in cooperation with the medial portion  224  of the shell  218 . 
   Another preferred embodiment is shown in  FIGS. 5   a-c . In this embodiment the combined insert and hosel  316  includes a hosel  317  of the offset type as already described with respect to  FIGS. 3   a - 3   e , and the insert  321  is of the tubular type already described with respect to  FIGS. 2   a - 2   e . The shell  318  has a medial portion  324  below the insert to define a back shelf and cavity. The shell also has a heel portion  320  and a toe portion  322  similar to those portions of the embodiment of  FIGS. 2   a-e . The embodiment of  FIGS. 5   a-c  is of the well known and often preferred cavity back type wherein the medial portion  324  and a sole wall  326  of the shell  318  are integral to form the sole  325  of the club while there is a back cavity  356  above the medial portion  324  of shell  318 . In this preferred embodiment, the insert has longitudinally extending top wall  343 , bottom wall  348 , striking wall  344  and back wall  346  which define a longitudinal insert cavity  350  extending from the base  342 . The top wall  343  provides the top surface  319  for optimum golfer viewing and alignment of the integral hosel and insert with the club grip and the ball. The striking wall  344  is canted slightly to define a striking surface  328  that provides a slight loft. 
   The embodiments of  FIGS. 6   a - 6   c  is preferred by some golfers because of the enhanced shape of the upper surfaces to provide optimum alignment. As shown in  FIGS. 6   a-c , the hosel  416  is of the double-curved type as explained in some detail with respect to  FIGS. 1 and 2   a-e . The insert  421  is of the box-type, very similar to that shown and described with respect to  FIGS. 2   a-e . In the insert  421 , the cavity  450  is defined by a bottom wall  448  which also comprises the forward portion of the sole  425 . The shell  418  has a sole surface  458  defined by toe portion  422 , heel portion  420  and medial portion  424 . Sole surface  458  aligns with the sole portion of bottom wall  448  of insert  421  to define sole  425 . 
   In this embodiment the top wall  443  of the insert  421  extends rearwardly in the sweet spot area to enhance alignment. The top wall  443  is chevron shaped with the central point spaced longitudinally from the hosel  417  to define an alignment portion  476  of the top sighting surface  419  in the nature of a chevron. This surface  419  may include surface treatment such as embossed lines, arrows or the like to further augment alignment accuracy. The shell  418  has a chevron portion  466  rearwardly of the insert  421  and shaped to conform to the chevron of insert  419  to provide enhanced structural integrity and an aesthetic configuration for the back cavity  462 . The transverse projection  464  extends rearwardly from the insert  421  and is interfitted into the corresponding portions of the shell  418  for enhanced structural integrity. 
   Referring to  FIGS. 7   a - 7   c ,  FIG. 7   a  is a perspective view of another embodiment  516  of the clubhead constructed in accordance with this invention. This embodiment includes an integral insert and hosel  516  comprising the insert  521  and the hosel  517  formed as a unit with a fairing  534 . In the embodiments of  FIGS. 7   a-c , the insert  521  is a forward blade  544  which defines the insert striking surface  528  and is connected to an insert base  542  which also comprises the underlying base of the hosel  517 . In this embodiment the striking surface  528  is flat but canted to provide a slight loft within the guidelines of the P.G.A. The shell  518  includes a heel portion  520 , a toe portion  522 , and a medial portion  524  which is integral with a sole wall  526  and a top wall  552 . The insert  521  includes the striking face wall  544  integral with the base portion  542  having top surface  543  and the hosel  517 . The shell  518  is formed to define a cavity  550  comprising longitudinal top wall  552 , bottom wall  526  and medial wall  524 , in cooperation with the heel and toe portions  520  and  522 . The cavity  550  and insert  521  are configured to provide the desired sound as the striking surface  528  impacts with the golf ball. The embodiment of  FIGS. 7   a-c  includes a back cavity  562  to provide the desired polar weight distribution and the optimum appearance from the golfer&#39;s perspective as he sights down the shaft and hosel. 
   The embodiment of  FIGS. 8   a - 8   c  has a configuration similar to the embodiment of  FIGS. 6   a-c . However, in this embodiment the hosel  617  is connected through the base portion  642  to a channel-shaped insert including the striking surface wall  644 , a bottom wall  648 , and an extended top wall  643 . Cavity  650  is defined by those three insert walls and the medial portion  624  of the shell. In the embodiment of  FIGS. 8   a-c , the top wall  643  of the insert has a rectangular sighting surface  619  behind the striking surface  628 . A chevron  666  is formed behind the insert  621  in the medial portion  624  of shell  618 . The bottom wall  648  of the insert is disposed above the sole surface  625  which is defined and established by the shell sole wall  626 . The embodiment of  FIGS. 8   a-c  has a modified back cavity  662   a  and  662   b  on respective sides of shell chevron  666  which optimizes the balance and weight distribution of the club and emphasizes the sighting benefits of the chevron  666 . 
   Yet another embodiment of the invention is shown in  FIGS. 9   a - 9   e . In this embodiment the combined insert and hosel  716  is illustrated incorporating a curved hosel  717  similar to that shown in  FIGS. 1 and 2 . The hosel  717  of the insert/hosel  716  is combined with a solid insert  721  having a sighting surface  719 , a bottom sole  748 , a striking face  744 , and a back face  746 . The top wall  743  is provided with a sighting lines or other indicia  782  for enhanced sighting and appearance of the clubhead. The sighting indicia  782  can be one line or a pattern formed in the surface of the insert as shown in  FIGS. 9   a-e . The indicia  782  can also be on the surface or raised above the top surface of the insert. 
   A back cavity  762  is defined by the medial shell portion  724  and back face  746  of insert  721 . Back cavity  762  joins a rear shelf  756  of shell  718 . The shelf configuration includes large heel portion  720  and toe portion  722  and the thin medial shelf portion  724  configured to add polar weight to the overall club balance with the toe shelf  770  and the heel shelf  772  providing enhanced polar balance and the desirable shelf appearance. The medial portion  724  of the shell cooperates with the toe portions  770  and heel portions  772  and with the insert  721  to define the sole surface  725  of the embodiment of  FIGS. 9   a-e.    
   The specific configuration of the combined insert and hosel  716  in cooperation with the clubhead end of the shaft  714  is shown partially exploded and partially in section in  FIG. 9   d . Where the combined insert and hosel  716  and the shaft  714  are to be formed of the same material they can be formed as a single unit. The hosel in all of the embodiments described herein is preferably reinforced with a central armature  778  formed within the hosel  717 . As illustrated in  FIG. 9   d , partially in section, and in  FIG. 9   e , in cross section, the armature  778  is configured to the shape of the hosel  717  and extends into the insert  721 . The hosel and insert  716  is preferably formed of a lightweight material and, in particular, nonmetallic high strength materials such as graphite composites and fiberglass and resin composites. Using such materials and the illustrated configuration, the armature  778  is cast within the hosel  717  and extends into the insert  721  as well. The sighting line  782  formed in the top surface  743  of insert  719  may be employed in all embodiments. 
   In preferred embodiments of the invention, the hosel at its upper end has a reduced diameter extension  774  to receive the hollow clubhead end of the shaft  714  (shown partially broken away and exploded above the hosel  717  for clarity). 
   Another embodiment of the invention similar to that of  FIGS. 9   a-e  is the golf club exemplified by  FIG. 9   f . The clubhead of  FIGS. 9   a-c ,  9   e  and  9   f  is the same as that shown in  FIGS. 9   a-e . It has a polar toe shelf and a polar heel shelf  972  corresponding to toe shelf  770  and heel shelf  772  in  FIG. 9   a . The insert  921  and hosel  917  are formed of a non-metallic material such as a graphite resin around the armature  978 . The non-metallic shaft  980  is also formed of the same non-metallic material such as a graphite resin. The reduced diameter extension  974  conforms to the hollow shaft  980 . The crevice  982  formed in the top of the insert  921  provides a sighting aid and the bottom surface  948  comprises the sole of the club in cooperation with shell sole surface  925 . The insert  921  defines a striking surface  944  and a back face  946 . 
   Referring now to  FIGS. 10   a - 10   d , the preferred embodiment shown therein has a combined insert and hosel  816  in cooperation with the shell  818 . 
   However, embodiments according to  FIGS. 10   a-d  have a toe and heel configuration significantly different from that illustrated in the other embodiments. In the embodiment of  FIGS. 10   a-d , the shell  818  is configured to define open heel and toe ends. The shell  818  has a medial portion  826  secured to and underlying the insert  821  and a shelf portion  824  extending rearwardly to define a back shelf and cavity defining an extended sole surface  825 . In the heel and toe regions, the shell  818  has a heel portion  820  including a cap portion  874 , and the toe portion  822  similarly provides a cap portion  876 . High mass density weights are configured to fit under the heel and toe caps  874 ,  876 . The heel high mass density polar weight  878  is conformed to the heel cap  874  and defines a part of the sole  825 . Similarly, the toe high mass density polar weight  880  is shaped to conform to the toe cap  876 , is secured thereto and provides the toe portion of sole  825 . In a typical implementation of these embodiments, the shell may be fabricated from lightweight metal materials such as aluminum or brass or may even be fabricated from composite materials. The polar weights  878  and  880  form a part of the shell and are preferably of higher mass density such as tungsten or steel to provide the polar weight distribution in the shell that enhances the force dynamics during the putting motion. 
   While various embodiments of the invention have been described incorporating various elements of the invention in different optimum combinations, the overall objectives of the invention and the specific enhancements described with respect to certain embodiments are all parts of the invention. It is contemplated that the invention may be implemented in such various combination all of which are intended to be encompassed within the scope of the following claims.