Golf club

• US 5,916,040 A
• Filed: 12/31/1997
• Issued: 06/29/1999
• Est. Priority Date: 10/23/1997
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Senkeikagakukenkyujyo
• Original Assignee: Kabushiki Kaisha Senkeikagakukenkyujyo
• Inventors: Umazume, Kosuke
• Primary Examiner(s): Passaniti, Sebastiano
• Application Number:
  US09/001,641
• Time in Patent Office: 545 Days
• Field of Search: 473/316, 473/317, 473/282, 473/228, D21/757
• US Class Current: 473/317
• CPC Class Codes: A63B 2225/01 Special aerodynamic features, e.g. airfoil shapes, wings or air passages
• 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 60/006 Surfaces specially adapted for reducing air resistance
• 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: A63B 60/42 Devices for measuring, verifying, correcting or customising the inherent characteristics of golf clubs, bats, rackets or the like, e.g. measuring the maximum torque a batting shaft can withstand

Abstract

A golf club capable of being swung faster than a conventional golf club having a club shaft, of which cross-section is circular, is newly invented. The golf club according to the invention has a club shaft, at least a part of which has an arcuate cross-section such as a semicircle on a face side of a club head and has a square cross-section such as a dovetail groove-shape on a back side of the head.

Claims

1. A golf club wherein:

a cross-sectional shape of at least a portion of a golf shaft is deformed to be an uncircular shape which can reduce an air resistance from a face side toward a tail side of a club head, thereby to increase a head speed of said club, said uncirculary shaped cross-section having an arcuate shape toward said face side of said club bead and a square shape toward said tail side of said club head, two opposite sides of said square shape intersecting respectively a third side so as to make respective interior angles smaller than 90°

to form substantially a dove tail groove-shaped cross-section.

2. The golf club according to claim 1, wherein:

said uncircularly shaped cross-section of said golf shaft is symmetrical with respect to a plane, which includes a center axis of said shaft and is proximately parallel to a target direction of a golf ball to be hit by said club.

3. The golf club according to claim 1, wherein:

said uncircularly shaped cross-section of said golf shaft is symmetrical with respect to said plane, which includes said center axis of said shaft and is approximately parallel to said target direction of said golf ball to be hit by said club.

4. The golf club according to claim 1, wherein said arcuate shape toward said face side of said club head has a radius R and said golf shaft has a face side to tail side length 2R.

5. The golf club according to claim 1, wherein said arcuate shape toward said face side of said club head has a radius R and said third side of said square shape has a length 1.12×

2R.

6. The golf club according to claim 1, wherein said arcuate shape toward said face side of said club head has a radius R, said golf shaft has a face side to tail side length 2R, and said third side of said square shape has a length 1.12×

2R.

7. The golf club according to claim 1, wherein only a portion of said golf shaft is deformed to be an uncircular shape.

8. The golf club according to claim 1, wherein substantially all of said golf shaft below a grip area is deformed to be an uncircular shape.

9. A golf club shaft comprising:

at least a portion of the golf club shaft having an uncircular cross-sectional shape with an arcuate portion toward a first face and a square portion toward a second face, said square portion comprising two opposite sides intersecting a third side so as to form two angles smaller than 90°

to form substantially a dovetail groove-shaped cross-section.