Golf club tip insert

Abstract

The invention provides an insert for a golf club shaft that stiffens and strengthens the tip of the shaft and reduces oscillations in the shaft during the swing of the club and dampens vibrations due to impact with the golf ball and/or the ground. In preferred embodiments, the insert comprises a rod portion that increases stiffness and foam and adhesive portions that dampen vibration.

1 . A golf club comprising: 
 a substantially cylindrical shaft having a proximal shaft end, a distal shaft end, and a distal hollow region disposed adjacent the distal shaft end;    a club head having a hosel for receiving the distal shaft end, the hosel having an exit point and having an overlap region wherein the hosel and the distal hollow region of the shaft overlap each other; and    a shaft insert disposed within the distal hollow region of the shaft, the shaft insert comprising: 
 a rod portion having an outer rod surface, a distal rod end and a proximal rod end; and  
 one or more spacers for substantially centering the rod portion within the distal hollow region of the shaft.  
   
   
   
       2 . The golf club of  claim 1  wherein the rod portion of the shaft insert is hollow.  
   
   
       3 . The golf club of  claim 1  wherein the rod portion of the shaft insert is cylindrical.  
   
   
       4 . The golf club of  claim 1  wherein the rod portion of the shaft insert is tapered from the proximal rod end to the distal rod end.  
   
   
       5 . The golf club of  claim 1  wherein the rod portion of the shaft insert is formed from an isotropic homogenous material.  
   
   
       6 . The golf club of  claim 1  wherein the rod portion is formed from a material selected from the group consisting of steel, aluminum titanium, fiberglass and graphite composite.  
   
   
       7 . The golf club of  claim 1  wherein the rod portion of the shaft insert has a length of about 2 to 15 inches.  
   
   
       8 . The golf club of  claim 1  wherein the one or more spacers of the shaft insert are formed of a resilient polymeric foam material.  
   
   
       9 . The golf club of  claim 1  wherein the one or more spacers of the shaft insert are adhesively bonded to the rod portion.  
   
   
       10 . The golf club of  claim 1  wherein the one or more spacers of the shaft insert comprise compliant adhesive material disposed between the outer rod surface and an inner surface of the distal hollow region of the shaft.  
   
   
       11 . The golf club of  claim 10  wherein the compliant adhesive material is selected from the group consisting of rubber cement, silicon caulk and latex caulk.  
   
   
       12 . The golf club of  claim 1  wherein the one or more spacers of the shaft insert comprise one or more strips of compliant material disposed between the outer rod surface and an inner surface of the distal hollow region of the shaft.  
   
   
       13 . The golf club of  claim 12  wherein the one or more strips comprise a plurality of strips spaced apart radially about the outer rod surface of the rod portion and disposed substantially parallel to an axial centerline of the rod portion.  
   
   
       14 . The golf club of  claim 12  wherein each of the one or more strips forms a helix about the outer rod surface of the rod portion.  
   
   
       15 . The golf club of  claim 12  wherein one or more of the one or more strips are segmented about the outer rod surface of the rod portion.  
   
   
       16 . The golf club of  claim 1  wherein the one or more spacers of the shaft insert are formed as an integral part of the outer rod surface Of the rod portion.  
   
   
       17 . The golf club of  claim 1  wherein the distal rod end of the rod portion of the shaft insert is disposed adjacent the distal shaft end.  
   
   
       18 . The golf club of  claim 1  wherein the distal rod end of the rod portion of the shaft insert is disposed within the overlap region of the hosel.  
   
   
       19 . The golf club of  claim 1  wherein the exit point of the hosel is disposed relative to the rod portion between the distal rod end and the proximal rod end.  
   
   
       20 . A golf club comprising: 
 a shaft having proximal and distal ends and comprising a plurality of tubular sections each having an inner surface of a diameter different from the other tubular sections, the tubular sections including a first tubular section having a first inner diameter and a second tubular section having a second inner diameter which is less than the first inner diameter, the second tubular section disposed closer than the first tubular section to distal end of the shaft;    a shaft insert disposed at least partially within the first and second tubular sections of the shaft, the shaft insert comprising: 
 a rod portion having an outer rod surface with an outer rod diameter, a distal rod end, a proximal rod end, a distal rod region disposed adjacent the distal rod end and a proximal rod region disposed adjacent the proximal rod end:  
 a tubular resilient portion disposed between the outer rod surface of the proximal rod region and the inner surface of the first tubular section of the shaft; and  
 one or more spacers disposed between the outer surface of the distal rod region and the inner surface of the second tubular section of the shaft.  
   
   
   
       21 . The golf club of  claim 20  wherein the rod portion of the shaft insert is hollow.  
   
   
       22 . The golf club of  claim 20  wherein the rod portion of the shaft insert is cylindrical.  
   
   
       23 . The golf club of  claim 20  wherein the rod portion of the shaft insert is tapered along its length from the proximal rod end to the distal rod end.  
   
   
       24 . The golf club of  claim 20  wherein the rod portion of the shaft insert is composed of an isotropic homogenous material.  
   
   
       25 . The golf club of  claim 20  wherein the rod portion of the shaft insert is formed from a material selected from the group consisting of aluminum, titanium, fiberglass, graphite composite.  
   
   
       26 . The golf club of  claim 20  wherein the rod portion of the shaft insert has a length of between about 2 inches and about 15 inches.  
   
   
       27 . The golf club of  claim 20  wherein the tubular resilient portion of the shaft insert is composed of a polymeric foam material.  
   
   
       28 . The golf club of  claim 20  wherein the tubular resilient portion of the shaft insert is bonded to the rod portion of the shaft insert by an adhesive.  
   
   
       29 . The golf club of  claim 20  wherein the tubular resilient portion of the shaft insert is bonded to the inner surface of the second tubular section of the shaft by an adhesive.  
   
   
       30 . The golf club of  claim 20  wherein the tubular resilient portion of the shaft insert has a length of between about 1 inch and about 4 inches.  
   
   
       31 . The golf club of  claim 20  wherein the one or more spacers of the shaft insert are formed of a resilient polymeric foam material.  
   
   
       32 . The golf club of  claim 20  wherein the one or more spacers of the shaft insert are adhesively bonded to the rod portion.  
   
   
       33 . The golf club of  claim 20  wherein the one or more spacers of the shaft insert comprise compliant adhesive material selected from the group consisting of rubber cement, silicon caulk and latex caulk.  
   
   
       34 . The golf club of  claim 20  wherein the one or more spacers of the shaft insert comprise a plurality of compliant strips spaced apart radially about the outer rod surface and disposed substantially parallel to an axial centerline of the rod portion.  
   
   
       35 . The golf club of  claim 20  wherein the one or more spacers of the shaft insert comprise a plurality of compliant strips, wherein each of the one or more compliant strips forms a helix about the outer rod surface.  
   
   
       36 . The golf club of  claim 20  wherein the one or more spacers of the shaft insert are formed as an integral part of the outer rod surface.  
   
   
       37 . The golf club of  claim 20  wherein the distal rod end of the rod portion of the shaft insert is disposed adjacent the distal shaft end of the shaft.  
   
   
       38 . A shaft insert for a golf club, wherein the golf club has a substantially cylindrical shaft with a proximal shaft end disposed adjacent a grip of the golf club, a distal shaft end disposed adjacent a club head of the golf club, and a distal hollow section disposed adjacent the distal shaft end, the distal hollow section defined by an inner shaft diameter, the shaft insert comprising: 
 a rod portion configured to be inserted into the distal hollow section of the shaft, the rod portion having an outer rod diameter which is less than the inner shaft diameter; and    means for substantially centering the rod portion within the distal hollow section of the shaft when the rod portion is inserted therein.    
   
   
       39 . A method for installing a shaft insert in a substantially cylindrical hollow shaft of a golf club, the shaft having a proximal shaft end, a distal shaft end and a distal hollow region disposed adjacent the distal shaft end, the shaft insert having a proximal insert end and a distal insert end, the method comprising the steps of: 
 (a) swabbing an adhesive material inside the distal hollow region of the shaft;    (b) inserting the distal insert end into the proximal shaft end;    (c) pushing the shaft insert toward the distal shaft end until the distal insert end is adjacent the distal shaft end;    (d) removing any excess adhesive material that exits the distal shaft end; and    (e) curing the adhesive material within the shaft.    
   
   
       40 . The method of  claim 39  wherein the shaft insert is hollow along the length of the shaft insert between the proximal insert end and the distal insert end, the method further comprising removing any adhesive material that may have migrated into the hollow region of the shaft insert, thereby ensuring that an open airway passage exists from the proximal shaft end to the distal shaft end.