Golf club

Abstract

A golf club comprises a shaft formed of a plurality of co-axially disposed tubes connected to one another at a stabilizing joint or joints. Shaft has an upper section forming a grip and a lower section connected to club head. Tubes are parallel-sided and of differing cross-sectional sizes. The lower section is constituted by the tube of smallest cross section. The relative diameters of the tubes are such that the upper end of a tube is receivable within the bore at the lower end of its neighbor. Preferably, the material from which tubes are formed is selected from: (a) a titanium alloy; (b) a combination of (i) an extruded polymeric matrix reinforced with continuous, straight, pre-stressed and tensioned carbon fibers, the fibers being aligned with the longitudinal axis of shaft, and (ii) continuous filament windings that are also pre-stressed, tensioned and unbroken, or (c) a combination of materials from categories (a) and (b).

What is claimed is:  
     
         1 . A golf club shaft for a grip portion and a club head, the golf club shaft comprising: 
 a first tube defining a first end with a first-tube cross-sectional area and a second end with the first-tube cross-sectional area, the first tube thereby being parallel-sided; and    a second tube defining a first end with a second-tube cross-sectional area and a second end with the second-tube cross-sectional area, the second tube thereby being parallel-sided, the second-tube cross-sectional area being smaller than the first-tube cross-sectional area, the first and second tubes being co-axially disposed, the golf club shaft being connectable to the grip portion and club head such that a distance between the first end of the first tube and the grip portion is smaller than a distance between the second end of the second tube and the grip portion, and a distance between the second end of the second tube and the club head is smaller than a distance between the first end of the first tube and the club head, wherein the first tube includes a first material selected from the group consisting of: 
 (a) a titanium alloy; or  
 (b) a combination of 
 (i) an extruded polymeric matrix reinforced with continuous, straight, pre-stressed and tensioned carbon fibers, the fibers being aligned with the longitudinal axis of the golf club shaft, and  
 (ii) continuous filament windings that are pre-stressed, tensioned and unbroken, and wherein the second tube includes a second material selected from the group consisting of:  
 
 (a) a titanium alloy; or  
 (b) a combination of 
 (i) an extruded polymeric matrix reinforced with continuous, straight, pre-stressed and tensioned carbon fibers, the fibers being aligned with the longitudinal axis of the golf club shaft, and  
 (ii) continuous filament windings that are pre-stressed, tensioned and unbroken.  
 
   
     
     
         2 . A golf club shaft as claimed in  claim 1  wherein the first tube is connected to the second tube.  
     
     
         3 . A golf club shaft as claimed in  claim 2  further including a ferrule acting as a coupling device between the first and second tubes.  
     
     
         4 . A golf club shaft as claimed in  claim 3  wherein the ferrule includes titanium or an alloy thereof.  
     
     
         5 . A golf club shaft as claimed in  claim 1  wherein the first end of the second tube is in the second end of the first tube.  
     
     
         6 . A golf club shaft as claimed in  claim 5 , wherein first tube defines an internal diameter, and the first and second tubes overlap by an amount at least four times the internal diameter.  
     
     
         7 . A golf club shaft as claimed in  claim 1  wherein the first tube is directly connectable to the grip portion.  
     
     
         8 . A golf club shaft as claimed in  claim 1  wherein the second tube is directly connectable to the club head.  
     
     
         9 . A golf club shaft as claimed in  claim 1  wherein the first tube includes a combination of: 
 (i) extruded polymeric matrix reinforced with continuous, straight, pre-stressed and tensioned carbon fibers, the fibers being aligned with the longitudinal axis of the golf club shaft, and  
 (ii) continuous filament windings that are pre-stressed, tensioned and unbroken.  
 
     
     
         10 . A golf club shaft as claimed in  claim 9 , further including a ferrule that overlaps or partially encases the fiber ends.  
     
     
         11 . A golf club shaft as claimed in  claim 10  wherein the polymeric matrix is a thermosettable material.  
     
     
         12 . A golf club shaft as claimed in  claim 9  wherein the polymeric matrix is a thermosettable material.  
     
     
         13 . A golf club shaft as claimed in  claim 9  wherein the first tube is formed by pultrusion and subsequent cutting to a desired length.  
     
     
         14 . A golf club shaft as claimed in  claim 1  wherein the second tube includes titanium alloy.  
     
     
         15 . A golf club shaft as claimed in  claim 1  wherein a ferrule is joined to the club head.  
     
     
         16 . A golf club shaft for a grip portion and a club head, the golf club shaft comprising: 
 a first tube defining a first end with a first-tube cross-sectional area and a second end with the first-tube cross-sectional area, the first tube thereby being parallel-sided; and    a second tube defining a first end with a second-tube cross-sectional area and a second end with the second-tube cross-sectional area, the second tube thereby being parallel-sided, the second-tube cross-sectional area being smaller than the first-tube cross-sectional area, the first and second tubes being co-axially disposed, the golf club shaft being connectable to the grip portion and club head such that a distance between the first end of the first tube and the grip portion is smaller than a distance between the second end of the second tube and the grip portion, and a distance between the second end of the second tube and the club head is smaller than a distance between the first end of the first tube and the club head, wherein the first tube includes a combination of: 
 (i) extruded polymeric matrix reinforced with continuous, straight, pre-stressed and tensioned carbon fibers, the fibers being aligned with the longitudinal axis of the golf club shaft, and  
 (ii) continuous filament windings that are pre-stressed, tensioned and unbroken, and wherein the second tube includes titanium alloy.  
   
     
     
         17 . A golf club shaft as claimed in  claim 16  wherein the first tube is formed by pultrusion and subsequent cutting to a desired length.  
     
     
         18 . A golf club shaft as claimed in  claim 16  wherein the first tube is connected to the second tube, and the golf club shaft further includes a ferrule acting as a coupling device between the first and second tubes.  
     
     
         19 . A golf club shaft as claimed in  claim 18  wherein the ferrule includes titanium or an alloy thereof.  
     
     
         20 . A golf club shaft as claimed in  claim 16  wherein a ferrule is joined to the club head.  
     
     
         21 . A golf club shaft as claimed in  claim 16  further including a ferrule that overlaps or partially encases the fiber ends.  
     
     
         22 . A golf club shaft as claimed in  claim 16  wherein the first tube is connected to the second tube at a stabilizing joint.  
     
     
         23 . A golf club shaft as claimed in  claim 16  wherein the first end of the second tube is in the second end of the first tube.  
     
     
         24 . A golf club shaft as claimed in  claim 23 , wherein first tube defines an internal diameter, and the first and second tubes overlap by an amount at least four times the internal diameter.  
     
     
         25 . A golf club shaft as claimed in  claim 16  wherein the first tube is directly connectable to the grip portion.  
     
     
         26 . A golf club shaft as claimed in  claim 16  wherein the second tube is directly connectable to the club head.