Abstract:
A golf club including an elongated hollow club shaft connected at one end to a golf club head, and having a grip mounted at an opposite end thereof. The club shaft is vented to permit and facilitate transmission of shock energy generated upon normal striking impact with a golf ball from the golf club in the form of acoustic energy, while substantially reducing or eliminating transmission of the shock energy in the form of vibration to the golfer&#39;s hands. In a first embodiment, a plurality of vents are formed in the club shaft at a location near the grip. In a second embodiment, a plurality of vents are formed in a cap mounted onto the club shaft at the grip end thereof.

Description:
[0001]    This application claims the benefit of U.S. Provisional Application No. 60/409,615, filed Sep. 9, 2002. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    This invention relates generally to improvements in golf clubs. More particularly, this invention relates to an improved golf club having a hollow shaft that is vented for permitting and facilitating transmission of shock energy generated upon normal striking impact with a golf ball from the golf club in the form of acoustic energy, to correspondingly and substantially reduce or eliminate transmission of the shock energy in the form of vibration to the golfer&#39;s hands.  
           [0003]    Golf clubs are well known in the art, to include a club head such as a wood-type or iron-type club head mounted at a lower end of an elongated club shaft. An upper end of the club shaft has a resilient grip mounted thereon and designed for comfortable manual grasping and swinging of the golf club to strike a golf ball. In modern golf clubs, the wood-type or iron-type club head is commonly formed from a cast or machined metal or metal alloy such as stainless steel, titanium alloy, and the like. The club shaft is commonly formed from a selected metal or metal alloy, or alternately from a nonmetallic composite material such as a graphite-based composite. The club shaft typically has an elongated tubular or hollow construction with a stiffness or flexibility (whip) characteristic that may be variably selected in accordance with the preferences of an individual golfer. The grip mounted onto the club shaft at the upper end thereof is normally formed from a selected resilient elastomer.  
           [0004]    During normal club use, substantial shock energy is generated when a golfer swings the club to strike a golf ball. This shock energy primarily takes the form of vibrations transmitted through the club shaft from the club head to the grip for tactile detection by the golfer&#39;s hands. In this regard, this vibrational energy is particularly susceptible to such feedback tactile detection when the point of golf ball impact with the club head is off-center, i.e., misaligned with an optimal ball striking zone commonly referred to as the “sweet spot”. For many amateur golfers, off-center ball impacts occur relatively frequently, resulting in a correspondingly frequent negative tactile feedback indicative of improper ball-head alignment and typically further indicative of a poor golf shot. Such negative tactile feedback can be discouraging, and thereby undermines enjoyment of the game.  
           [0005]    The present invention relates to an improved golf club having a vented club shaft, so that a substantial portion of the shock wave or shock energy generated upon ball impact can be transmitted or discharged from the club in the form of acoustic energy or sound, thereby significantly reducing or eliminating the transmission of the shock energy in the form of vibration to the golfer&#39;s hands.  
         SUMMARY OF THE INVENTION  
         [0006]    In accordance with the invention, a golf club is provided with a vented shaft to permit and facilitate transmission and discharge of shock energy, generated upon normal striking impact with a golf ball, from the golf club in the form of acoustic energy or sound, thereby substantially reducing or eliminating transmission of shock energy in the form of vibration to the golfer&#39;s hands.  
           [0007]    The improved golf club comprises an elongated hollow club shaft connected at one end to a golf club head, and having a grip mounted generally at an opposite end thereof. In one preferred form, the club shaft includes at least one and preferably a plurality of vent ports formed therein at a location near the grip. In an alternative preferred form, at least one and preferably a plurality of vent ports are formed in an end cap mounted onto the club shaft at the grip end thereof. In either embodiment, upon striking impact of the club head with a golf ball, a substantial portion of the resultant shock energy transmitted from the club head to the club shaft is discharged through the vent ports to the surrounding air in the form of acoustic energy or sound, which is both readily audible and distinctive. Conversely, any residual portion of this shock energy available for transmission to the golfer&#39;s hands in the form of vibration is significantly reduced.  
           [0008]    Other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    The accompanying drawings illustrate the invention. In such drawings:  
         [0010]    [0010]FIG. 1 is a perspective view of a golf club incorporating a vented shaft in accordance with the present invention;  
         [0011]    [0011]FIG. 2 is an enlarged fragmented perspective view corresponding generally with the encircled region  2 - 2  of FIG. 1;  
         [0012]    [0012]FIG. 3 is an enlarged transverse sectional view taken generally on the line  3 - 3  of FIG. 2;  
         [0013]    [0013]FIG. 4 is an enlarged fragmented perspective view similar to FIG. 2, but depicting a modified embodiment of the invention;  
         [0014]    [0014]FIG. 5 is an enlarged and fragmented sectional view illustrating one alternative preferred form of the invention;  
         [0015]    [0015]FIG. 6 is a top end view of a golf club shaft, taken generally on the line  6 - 6  of FIG. 5; and  
         [0016]    [0016]FIG. 7 is a fragmented exploded perspective view illustrating assembly of the components illustrated in the embodiment of FIGS. 4 and 5. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0017]    As shown in the exemplary drawings, an improved golf club referred to generally by the reference numeral  10  is provided with an elongated vented hollow club shaft  12 . The club shaft  12  is connected at a lower end to a club head  14  (FIG. 1), and carries a resilient grip  16  mounted at an upper end thereof. In use, upon swinging of the golf club to strike the club head  14  against a golf ball (not shown), the vented shaft  12  permits and facilitates transmission of resultant ball impact shock energy from the club in the form of acoustic energy or sound, while significantly reducing or eliminating transmission of the shock energy in the form of vibration to the golfer&#39;s hands.  
         [0018]    The illustrative golf club  10  shown in FIG. 1 has an overall, generally conventional construction to include the elongated club shaft  12  connected to the club head  14  and having the resilient grip  16  mounted thereon. In this regard, FIG. 1 shows the club head  14  in the form of a wood-type club head having a front ball impact face  18  for striking a golf ball. In accordance with modern golf club construction, the wood-type head  14  may comprise a so-called metal wood club head comprising a hollow head construction formed from a selected cast or machined metal or alloy such as stainless steel, titanium alloy, etc. As shown, the club head  14  has a hosel  20  formed generally at a heel end thereof for connection in any suitable and known manner to the lower end of the club shaft  12 .  
         [0019]    While the invention is shown and described herein with respect to a golf club  10  having a wood-type club head  14  as shown in the illustrative drawings, persons skilled in the art will recognize and appreciate that the club head may alternatively comprise any one of a standard set of iron-type golf clubs, a putter, or a sand or pitching wedge or the like.  
         [0020]    The club shaft  12  has an elongated hollow tubular construction extending from the connection thereof to the club head  14  to an upper end having the resilient grip  16  mounted thereon. The club shaft  12  may be formed from a suitable metal shaft material, such as stainless steel or the like, or alternatively formed from a nonmetallic material such as a graphite-based composite or the like. The specific stiffness or flexibility (whip) characteristics of the club shaft  12  may be expressly selected or tailored to suit the custom preferences of an individual golfer.  
         [0021]    The resilient grip  16  is shown in the form of a molded elastomer sleeve having a size and shape for slide-fit mounting onto the upper end of the golf club shaft  12 . The grip  16  preferably incorporates an external surface grid pattern or texture  22  (shown best in FIG. 2) for facilitated manual grasping and secure gripping by the player&#39;s hands. Alternative grip configurations are known, such as an elongated strip of elastomer or leather material for spiral wrapping about the upper end portion of the club shaft  12 .  
         [0022]    In use, as is well known and understood, the golfer grasps the grip  16  while manually swinging the club shaft  12  to drive the front impact face  18  of the club head  14  into impact engagement with a golf ball. As the club head  12  contacts the golf ball with a substantial shock impact, the ball is driven forwardly in the direction of club head movement. At the same time, substantial reaction forces are transmitted to the club head in the form of a shock wave or shock energy for dissipation by transmission along the club shaft  12  and further to the golfer&#39;s hands, typically in the form of vibrational energy. The magnitude of this vibrational energy can be significant, and is noticeable by tactile detection with the golfer&#39;s hands, particularly when the ball impact point on the club head face  18  is outside an optimal ball impact zone or sweet spot.  
         [0023]    In accordance with the present invention, the hollow club shaft  12  is vented so that a substantial portion of this shock wave or shock energy can be transmitted and discharged from the golf club in the form of acoustic energy or sound, rather than transmitted in the form of vibration to the golfer&#39;s hands. In this regard, in one preferred form of the invention, the club shaft  12  as shown in FIGS.  1 - 3  includes a plurality of small vent ports  24  formed therein at a location near but preferably a short distance below the lowermost end of the resilient grip  16 . FIG. 3 shows a plurality of eight small vent ports  24  formed at equiangular intervals about the club shaft circumference, with each vent port having a narrow width of about ⅛ inch and a length of about ½ inch, and with the array of vent ports  24  disposed about ¼-½ inch below the lowermost end of the grip  16 .  
         [0024]    [0024]FIG. 4 illustrates a modified embodiment of the improved golf club  10  as shown and described in FIGS.  1 - 3 . In particular, FIG. 4 shows a reinforcement ring or sleeve  25  mounted about the club shaft  12 , wherein this sleeve  25  has a plurality of vent ports  24 ′ formed therein in alignment with the vent ports  24  formed in the club shaft  12  as previously described and shown in FIGS.  1 - 3 . The vented reinforcement sleeve  25  may be formed from metal or other suitably stiff material for secure mounting onto the club shaft  12  in alignment with the vent ports  24 . This reinforcement sleeve  25  is normally used with a nonmetallic club shaft  12 , such as a graphite composite shaft, to strengthen the shaft in the region of the vent ports  24 .  
         [0025]    With this construction, it has been found that a significant portion of the ball impact shock energy transmitted from the club head  14  to the shaft  12  is emanated or discharged from the club shaft in the form of a readily audible and distinctive acoustic wave or sound. Such dissipation of a substantial portion of this ball impact shock energy significantly reduces the residual energy available for transmission in the form of vibration to the golfer&#39;s hands. As a result, the golfer is able to detect by tactile sensation little if any of this residual energy. Instead, each golf shot is accompanied by a more solid tactile sensation together with a distinctive audible ring or click emanating from the vent ports  24 , whereby the confidence level of the golfer is maintained despite an occasion misaligned or mishit golf shot.  
         [0026]    FIGS.  5 - 7  illustrate another alternative preferred form of the invention, wherein alternative vent ports  124  are formed in an end cap  26  having a size and shape for mounting onto the upper end of the club shaft  12 . More particularly, the cap  124  may be constructed from metal or molded plastic or the like, and includes the multiple vent ports  124  for communicating the interior of the club shaft  12  with the surrounding air. FIGS.  5 - 7  show the cap  26  to have a raised central body  28  having the vent ports  124  formed therein, in combination with a recessed peripheral flange  30  projecting radially outwardly therefrom. This flange  30  has a size and shape to overlie the upper end of the club shaft  12 , and is securely retained thereon by a radially in-turned lip  32  formed at the upper end of the resilient grip  16 . The lip  32  defines a central aperture  34  for seated reception and retention of the cap body  28 .  
         [0027]    In use, the vent ports  124  formed in the end cap  26  function in the same manner as previously described with respect to the vent ports  24  shown in FIGS.  1 - 3 . A substantial portion of the ball impact shock energy is transmitted through the vent ports  124  in the form of acoustic energy or sound, thereby significantly reducing the residual shock energy available for transmission in the form of vibration to the golfer&#39;s hands. The embodiment of FIGS.  5 - 7  is particularly suitable for retrofitting the invention to existing golf clubs.  
         [0028]    A variety of further modifications and improvements in and to the improved golf club head of the present invention will be apparent to those persons skilled in the art. Accordingly, no limitation on the invention is intended by way of the foregoing description and accompanying drawings, except as set forth in the appended claims.