Reduced weight golf club shafts

• US 5,820,483 A
• Filed: 01/13/1997
• Issued: 10/13/1998
• Est. Priority Date: 01/13/1997
• Status: Expired due to Term

• Current Assignee: Callaway Golf Company (Topgolf Callaway Brands Corp.)
• Original Assignee: Callaway Golf Company (Topgolf Callaway Brands Corp.)
• Inventors: Preece, Thomas W., Galloway, J. Andrew, Reyes, Herb
• Primary Examiner(s): Passaniti, Sebastiano
• Assistant Examiner(s): BLAU, STEPHEN LUTHER
• Application Number:
  US08/783,582
• Time in Patent Office: 638 Days
• Field of Search: 473/312, 473/316-323
• US Class Current: 473/316
• CPC Class Codes: A63B 53/02 Joint structures between the head and the shaft
• CPC Class Codes: A63B 53/10 Non-metallic shafts
• CPC Class Codes: A63B 60/00 Details or accessories of golf clubs, bats, rackets or the like
• CPC Class Codes: A63B 60/06 Handles
• CPC Class Codes: A63B 60/08 characterised by the material
• CPC Class Codes: A63B 60/10 with means for indicating correct holding positions A63B60/12 takes precedence
• CPC Class Codes: B29C 43/42 for undercut articles
• CPC Class Codes: B29C 53/821 Mandrels especially adapted for winding and joining
• CPC Class Codes: B29C 61/04 Thermal expansion
• CPC Class Codes: B29C 70/30 Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
• CPC Class Codes: B29C 70/86 Incorporated in coherent impregnated reinforcing layers, e.g. by winding
• CPC Class Codes: B29K 2105/101 Oriented
• CPC Class Codes: B29L 2023/00 Tubular articles B29L2024/00 takes precedence ; catheters B29L2031/7542
• CPC Class Codes: B29L 2031/5227 Clubs
• CPC Class Codes: Y10S 425/044 Rubber mold

Abstract

Improved methods for manufacturing a shaft for a golf club, devices useful in such methods, and golf club shafts manufactured in accordance with such methods. A plug is detachably affixed to a distal end of a mandrel. A plurality of plies of pre-preg composite sheet are wrapped around the mandrel and plug and, thereafter, heated causing the resin comprising the various plies to be cured. The mandrel is then removed from the formed shaft, leaving the plug as an integral part of the distal tip of the shaft.

Claims

1. A shaft for a golf club, said shaft comprising

a shaft body with a proximal end, a distal end, and an integral plug,

said shaft body having a generally frusto-conical shape, being tapered in a first direction at said distal end, and having a cavity extending along its longitudinal axis from said proximal end to said distal end, and

said integral plug having a profile that exhibits a taper in a direction opposite the direction of taper of said shaft body at said distal end and being affixed within said distal end of said shaft body.

2. The shaft of claim 1, wherein said plug comprises a thermally expansive material.

3. A shaft for a golf club, said shaft comprising

a shaft body and an integral plug,

said shaft body having a generally cylindrical shape that tapers in a first direction and having a cavity formed in and extending along a longitudinal axis thereof,

said integral plug being affixed within a distal end of said shaft body and having a proximal end wherein a cavity for detachably receiving a mandrel tip is provided.

4. The shaft of claim 3, wherein said integral plug has a taper in a direction opposite to said first direction.

5. The shaft of claim 3, wherein said integral plug has a taper in a direction common to said first direction.

6. The shaft of claim 3, wherein said integral plug is formed from a thermally expansive material.

7. A shaft for a golf club, said shaft comprising

a shaft body and an integral plug,

said shaft body having a generally cylindrical shape that tapers in a first direction and having a cavity formed in and extending along a longitudinal axis thereof,

said integral plug comprising a thermally expansive material, being affixed within a distal end of said shaft body and having a proximal end wherein a cavity for detachably receiving a mandrel tip is provided.

8. A shaft for a golf club, said shaft comprising:

a body comprising a plurality of composite fibers fixed within a binding matrix, said body having a generally cylindrical shape that tapers in a first direction and having a central cavity extending along a longitudinal axis thereof, and

an integral plug, said integral plug being co-cured within a distal region of said central cavity of said body such that a portion of said binding matrix adheres to and fixes a position of said integral plug within said distal region of said central cavity,

wherein said integral plug has a proximal end wherein a cavity for detachably receiving a mandrel tip is provided.