Golf club with adjustable-length shaft

Abstract

A secure golf club, of the “wood” or “iron” variety intended for high-speed impact of a golf ball, whose shaft may be lengthened or shortened in a relatively quick and easy manner. In a preferred embodiment, the shaft includes one or more shaft extension sections rigidly attached to the shaft or to each other by reverse-thread connections, to reduce the tendency of the shaft sections to loosen during play. Shaft locking mechanisms are also preferably employed for preventing relative axial movement along the shaft and between the shaft sections. Preferably, the shaft has a substantially continuous and substantially smooth outer periphery, substantially void of gaps or steps creating stress points within the shaft that might lead to fracture or breakage of the golf club during play.

1 . A swingable golf club whose shaft may be lengthened or shortened in a relatively quick and easy manner, comprising: 
 a club head intended for high-speed impact of a golf ball;    a shaft including a first shaft portion having a predetermined shaft length, the first shaft portion being permanently attached to the club head, the shaft also including at least a first shaft extension section removably attached by reverse-thread connections at a first connection location to the first shaft portion and removably attached at a second connection location to a shaft section carrying a grip;    one or more locking mechanisms for preventing relative axial movement at the connection locations along the shaft;    wherein the shaft has a substantially continuous and substantially smooth outer periphery, substantially void of gaps or steps at the connection locations that create stress points within the shaft leading to substantial instances of fracture or breakage of the golf club during play.    
   
   
       2 . The golf club of  claim 1 , wherein the shaft comprises low-carbon steel.  
   
   
       3 . The golf club of  claim 1 , wherein the first shaft extension may be substituted for another first shaft extension having a different length.  
   
   
       4 . The golf club of  claim 1 , wherein the shaft further comprises at least first and second shaft extension sections, with the second shaft extension section being connected at opposing ends at further connection locations to the first shaft extension section and to the shaft section carrying the grip.  
   
   
       5 . The golf club of  claim 4 , wherein either of the first or the second shaft extensions may be substituted for another shaft extension having a different length.  
   
   
       6 . The golf club of  claim 1 , wherein the first shaft extension comprises one of a plurality of shaft extensions of predetermined lengths.  
   
   
       7 . The golf club of  claim 1 , wherein the first shaft portion terminates in a first threaded end., and wherein the first shaft extension section terminates in a second threaded end, and wherein the first and second threaded ends may be quickly and easily threadably connected and disconnected using a reverse thread connection.  
   
   
       8 . The golf club of  claim 1 , wherein the first shaft extension has a length which is greater than about 4 inches.  
   
   
       9 . The golf club of  claim 1 , wherein the first shaft extension has a length which is greater than about 6 inches.  
   
   
       10 . The golf club of  claim 1 , wherein the first shaft extension has a length in the range of about 2-14 inches.  
   
   
       11 . The golf club of  claim 4 , wherein at least one of the first or second shaft extensions exceeds eight inches in length.  
   
   
       12 . The golf club of  claim 1 , wherein the one or more locking mechanisms comprise an annular clip surrounding a portion of the shaft at a connection location.  
   
   
       13 . The golf club of  claim 12 , wherein the clip includes a tab for engaging adjacent grooves at a connection location.  
   
   
       14 . The golf club of  claim 1 , wherein the one or more locking mechanisms comprise a set screw.  
   
   
       15 . The golf club of  claim 14 , wherein the set screw has a head only accessible by a non-standard fastening device.  
   
   
       16 . The golf club of  claim 15 , wherein the non-standard fastening device comprises an Allen wrench.  
   
   
       17 . The golf club of  claim 1 , wherein any adjacent shaft or shaft extension sections are attached using a reverse-thread connection.  
   
   
       18 . A secure, swingable golf club having a shaft capable of being lengthened or shortened, comprising: 
 a club head;    a shaft portion permanently attached to the club head;    one or more shaft extension sections rigidly attached by reverse-thread connections to the shaft portion and to a shaft section carrying the grip;    one or more locking mechanisms for preventing relative axial movement along the shaft;    wherein the shaft has a substantially continuous and substantially smooth outer periphery, substantially void of gaps or steps at the connection locations.    
   
   
       19 . The golf club of  claim 18 , wherein the locking mechanism comprises a tubular sleeve.  
   
   
       20 . A golf club set including golf clubs whose shafts may be lengthened or shortened, comprising: 
 a plurality of wood-type or iron-type golf clubs having club heads intended for high-speed impact of a golf ball;    each of the golf clubs having a shaft portion permanently attached to a club head;    each of the shaft portions being capable of attachment to at least one shaft extension section, opposing ends of the at least one shaft extension comprising connection locations;    locking mechanisms at the connection locations for preventing relative axial movement along the shaft;    wherein the shaft of each of the golf clubs has a substantially continuous and substantially smooth outer periphery.    
   
   
       21 . The golf club set of  claim 20 ,wherein the shaft is substantially void of gaps or steps at the connection locations that create stress points within the shaft leading to substantial instances of fracture or breakage of the golf club during play.  
   
   
       22 . The golf club set of  claim 20 , wherein the at least one shaft extension is attached to other portions of the shaft at the connection locations using reverse-thread connections.