Shaft for use in golf clubs and other shaft-based instruments and method of making the same

Abstract

A shaft for use in a golf-club or other shaft-based instrument, including a base member and a metal layer, and a method of making the same.

Description

BACKGROUND OF THE INVENTIONS [0001] 1. Field of the Inventions [0002] The present inventions relate generally to shaft-based instruments and, more particularly, to shafts for use in golf clubs and other shaft-based instruments. [0003] 2. Description of the Related Art [0004] Over the years, there have been a variety of attempts to improve shaft-based instruments such as golf clubs, ski poles and hockey sticks. With respect to golf clubs, many substitutes have been introduced for the hard wood shafts originally used in golf club drivers and irons. Early substitute materials included stainless steel and aluminum. More recently, carbon fiber reinforced resin shafts have become popular. Such shafts are typically hollow and consist of a shaft wall formed around a tapered mandrel. The use of fiber reinforced resin has allowed golf club manufacturers to produce shafts having varying degrees of strength, flexibility and torsional stiffness. Carbon fiber reinforced resin shafts have also bec...

AI Technical Summary

Benefits of technology

"The present invention provides shafts that have greater torsional and longitudinal stiffness than conventional fiber reinforced resin shafts. These shafts have a metal layer that facilitates precise location of the flex point and prevents breakage. The metal layer also strengthens the area of the tip section adjacent to the club head that is a frequent area of breakage in conventional golf club shafts. Overall, the shafts in this invention have improved performance and durability."

Problems solved by technology

Nevertheless, manufactures of shaft-based instruments are faced with a variety of design issues that have proven difficult to overcome using conventional fiber reinforced resin technologies.

One issue associated with shaft design is related to the torsional and longitudinal stiffness of the shafts and, in the golf club shaft context, the attempts of designers to increase torsional stiffness (especially near the club head) in order to improve shot accuracy and increase longitudinal stiffness in order to cope with the ever increasing swing velocities of golfers.

Another issue associated with shaft design is the location of the shaft flex point.

More specifically, the inability of shaft designers to precisely predict the location of the flex point when designing a shaft without using excessive amounts of composite material, which can lead to weight and thickness issues, can be problematic.

Breakage prevention is another important design issue.

Images