Patent Publication Number: US-2003236132-A1

Title: Golf club head with porous sole plate

Description:
BACKGROUND OF THE INVENTION  
       [0001] This application claims the benefit of U.S. Provisional Application No. 60/390,083, filed Jun. 20, 2002.  
       [0002] This invention relates generally to improvements in golf club heads of the so-called metal wood type. More particularly, this invention relates to an improved metal wood type club head designed for improved dissipation of shock energy generated upon normal striking impact with a golf ball, to correspondingly reduce transmission of such shock energy typically in the form of vibration to the golfer&#39;s hands via the associated club shaft.  
       [0003] Golf club heads of the so-called metal wood type are generally known in the art, wherein the shape of a traditional wood-type club head is reproduced in the form of a hollow metal shell or the like. In a typical construction, the club head comprises a base member or body formed by casting or forging or the like in an upwardly open shell-shaped configuration defining a sole plate and upstanding club head side walls, including a front face for striking a golf ball. This base member additionally includes a hosel for suitable connection to the end of a golf club shaft. The open top of the base member is normally closed by a cap plate which is typically welded thereto, to form the hollow metal head structure. In an alternative configuration, the base member or body can be formed as a downwardly open shell, and a sole plate is attached thereto as by welding to form the hollow club head structure.  
       [0004] Significant development effort has been directed to improving metal wood type golf clubs, to improve distance, accuracy, and overall playability in different conditions. Much of this effort has focused upon improvements in club head weight distribution, structural stiffness, and aerodynamics.  
       [0005] U.S. Pat. No. 5,851,159 is directed to an improved metal wood golf club head having a relatively large dome element incorporated into the sole plate. This dome element comprises an upwardly extending structure that effectively adjusts the club head weighting and the location of the so-called sweet spot for optimal ball impact. In addition, this dome element has been found to reduce the transmission of vibrational energy from the club head via the club shaft to the golfer&#39;s hands, resulting from shock impact of the club head faceplate with a golf ball. Instead, a significant portion of this impact shock energy is believed to be emanated or transmitted from the club head, by means of the dome element, in the form of a distinctive and audible ringing sound. Such reduction in the transmission of vibrational energy to and through the club shaft to the golfer&#39;s hands produces a more solid and crisp tactile feedback for each golf shot, and further reduces golfer fatigue in the course of a round of golf.  
       [0006] The present invention relates to a further improved golf club head of the metal wood type, designed for more effective transmission of ball impact shock energy from the club head in the form of a distinctive audible sound, to achieve a further reduction in the transmission of vibrational energy through the club shaft to the golfer&#39;s hands.  
       SUMMARY OF THE INVENTION  
       [0007] In accordance with the invention, a golf club head of the metal wood type is provided with a porous plate defining a portion of at least one wall thereof, such as at least a portion of the sole plate. Upon striking impact of the club head with a golf ball, the porous plate facilitates transmission of a significant portion of the resultant shock energy from the club head in the form of a distinctive audible sound output, with a corresponding substantial reduction in the transmission of vibrational energy through the associated club shaft to the golfer&#39;s hands.  
       [0008] In one preferred form of the invention, the club head is defined by an upwardly open and generally shell-shaped base member or body formed by metal casting or the like to define a sole plate bounded by upstanding side walls, including a front impact face or faceplate for striking a golf ball, a rear face, a heel segment, and a toe segment. A hosel is normally incorporated into the base member generally at the heel segment thereof, wherein the hosel is adapted for suitable connection to the lower end of a club shaft. A cap plate, which can also be formed by metal casting or the like, is provided for connection as by welding to the upper margins of the upstanding side walls to close the open top of the base member and thereby form a hollow metal wood club head. In one alternative configuration, the base member or body may be formed to include the cap plate with downwardly extending side walls for suitable connection as by welding to a separately formed sole plate.  
       [0009] At least one wall of the metal wood club head includes the porous plate. In a preferred form, the porous plate is mounted as by welding or the like to extend across and close an opening formed in the club head sole plate. The porous plate may be formed from a suitable rigid yet porous metal-based material, such as a disk-shaped plate formed from metallic balls interconnected as by sintering to define a rigid yet porous construction.  
       [0010] In use, upon normal striking impact of the club head faceplate with a golf ball, a significant portion of the resultant impact shock energy emanates or is transmitted from the club head through the porous plate to the surrounding air for dissipation in the form of a readily audible and distinctive sound. Conversely, any residual portion of this shock energy available for transmission to the club shaft, and ultimately to the golfer&#39;s hands, is significantly reduced.  
       [0011] 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  
     [0012] The accompanying drawings illustrate the invention. In such drawings:  
     [0013]FIG. 1 is a top perspective view of a metal wood-type golf club head;  
     [0014]FIG. 2 is a bottom perspective view of the golf club head of FIG. 1, illustrating a porous sole plate in accordance with the novel features of the invention;  
     [0015]FIG. 3 is an exploded bottom perspective view of the golf club head;  
     [0016]FIG. 4 is a toe end elevation view of the golf club head; and  
     [0017]FIG. 5 is an enlarged sectional view taken generally on the line  5 - 5  of FIG. 4. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0018] As shown in the exemplary drawings, an improved metal wood type golf club head referred to generally by the reference numeral  10  is provided. The improved club head  10  comprises a hollow head construction formed primarily from cast or forged metal components, and includes a porous plate  12  (FIGS.  2 - 5 ) defining a portion of at least one wall thereof such as at least a portion of a sole plate  14  of the club head  10 . Upon striking impact of the club head with a golf ball, the porous plate  12  facilitates transmission of a significant portion of the resultant shock energy from the club head in the form of a distinctive audible sound output, with a corresponding substantial reduction in the transmission of vibrational energy through an associated club shaft  16  to the golfer&#39;s hands.  
     [0019] The overall construction and configuration of the illustrative golf club head  10  generally conforms to existing metal wood technology, wherein an enclosed and hollow club head is formed from metal components or the like which are typically cast or forged from stainless steel, titanium or other selected metal or metal alloy. The club head  10  includes a base member or body  18  including a hosel  20  for suitable attachment to the lower end of the club shaft  16 . As shown, the base member  18  is formed as an upwardly open and generally shell-shaped structure to include the bottom sole plate  14  joined at its perimeter to upstanding side walls of the club head, namely, a front impact face or faceplate  24  for striking a golf ball, a rear face  26 , a toe segment or wall  28 , and a heel segment or wall  30 . The hosel  20  is normally formed at the inboard side of the heel segment  30  and is adapted for connection to the golf club shaft  16 . These upstanding side walls of the base member or body  18  are adapted for assembly with and secure attachment to a similarly constructed cap plate  32  which is normally welded thereto and then appropriately surface finished to provide an attractive hollow metal golf club head.  
     [0020] In accordance with the invention, at least one wall defining the club head  10  is defined by or includes as a portion thereof the porous plate  12 . In a preferred embodiment as shown in the illustrative drawings, the porous plate  12  comprises a generally circular or disk-shaped element having a size and shape for mounting as by welding within and substantially covering or closing a matingly shaped opening  34  (FIG. 3) formed generally centrally within the sole plate  14 .  
     [0021] The porous plate  12  comprises a structurally rigid element having a mass that is compatible with the overall weighting and center of gravity of the club head  10 , and further which does not compromise the structural integrity of the club head upon impact with a golf ball. Importantly, the porous plate  12  additionally provides a porous pathway which vents the interior of the club head  10  to the exterior. One preferred material for the porous plate comprises a matrix of small balls or spheres which are structurally compounded as by sintering to provide a rigid, lightweight and porous structure.  
     [0022] In use, upon normal impact of the club head faceplate  24  with a golf ball (not shown) in the course of a golf shot, a resultant and substantial shock wave is generated within and through the hollow metal club head  10 . A significant portion of this impact shock energy is emanated or transmitted from the club head  10  through the porous plate  12  to the surrounding air for dissipation in the form of a readily audible and distinctive sound. Conversely, any residual portion of this impact shock energy is significantly reduced, wherein such residual energy is otherwise undesirably available for transmission in the form of vibration to the club shaft  16 , and ultimately to the golfer&#39;s hands. This reduction in vibrational energy transmitted to the club shaft  16  and to the golfer&#39;s hands beneficially produces a golf club with a more solid and crisp tactile feedback for each golf shot, while at the same time reducing golfer fatigue in the course of a round of golf.  
     [0023] A variety of further modifications and improvements in and to the metal wood type golf club head of the present invention will be apparent to those persons skilled in the art. For example, it will be apparent that the porous plate  12  may be provided in virtually any selected size and shape, such as a recessed dome element, and may be mounted at a club head wall other than the sole plate  14  as shown. 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.