Golf club head with a high coefficient of restitution

• US 20020189356A1
• Filed: 04/10/2002
• Published: 12/19/2002
• Est. Priority Date: 04/18/2000
• Status: Active Grant

• Current Assignee: Laurent C. Bissonnette, Nicholas M. Nardacci, Raymond L. Poynor
• Original Assignee: Laurent C. Bissonnette, Nicholas M. Nardacci, Raymond L. Poynor
• Inventors: Bissonnette, Laurent C., Nardacci, Nicholas M., Poynor, Raymond L.
• Granted Patent: US 6,595,057 B2
• Time in Patent Office: Days
• US Class Current: 73/570
• CPC Class Codes: A63B 2209/00 Characteristics of used materials
• CPC Class Codes: A63B 53/0408 characterised by specific dimensions, e.g. thickness
• CPC Class Codes: A63B 53/0416 Heads having an impact surface provided by a face insert
• CPC Class Codes: A63B 53/045 Strengthening ribs
• CPC Class Codes: A63B 53/0454 Strengthening ribs on the rear surface of the impact face plate
• CPC Class Codes: A63B 53/0458 with non-uniform thickness of the impact face plate
• CPC Class Codes: A63B 53/0466 wood-type
• CPC Class Codes: A63B 60/00 Details or accessories of golf clubs, bats, rackets or the like
• CPC Class Codes: A63B 60/002 Resonance frequency related characteristics
• 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
• CPC Class Codes: G01N 2291/014 Resonance or resonant frequency
• CPC Class Codes: G01N 2291/02854 Length, thickness
• CPC Class Codes: G01N 29/045 by imparting shocks to the workpiece and detecting the vibrations or the acoustic waves caused by the shocks measuring resonant frequency G01H13/00; measuring strength properties by application of mechanical stress G01N3/00

Abstract

The present invention relates to a golf club head provided with a face and a body. The face has a central zone and a intermediate zone adjacent and surrounding the central zone. The central zone has a first flexural stiffness and the intermediate zone has a second flexural stiffness. The club head face is configured and dimensioned such that the first flexural stiffness is significantly greater than the second flexural stiffness such that upon ball impact with the face, the intermediate zone exhibits substantial deformation so that the central zone moves into the club head. At the same time, the central zone exhibits minimal deformation so that it moves into and out of the club head as a unit. Furthermore, the face exhibits a high coefficient of restitution.

Claims

1. A method of determining the coefficient of restitution of a golf club face comprising the steps of:

imparting a first impact force to the club face;

measuring a first primary resonant frequency of vibration for the club face; and

correlating the first primary resonant frequency to the coefficient of restitution.

2. The method of determining the coefficient of restitution of a golf club face of claim 1, further comprising the step of attaching a first mass to the golf club face prior to imparting the impact force.

3. The method of determining the coefficient of restitution of a golf club face of claim 2, wherein the first mass attached to the golf club face comprises an accelerometer.

4. The method of determining the coefficient of restitution of a golf club face of claim 3, wherein the accelerometer is attached to the geometric center of the club face.

5. The method of determining the coefficient of restitution of a golf club face of claim 4, wherein the accelerometer is attached to the club face with a high modulus adhesive.

6. The method of determining the coefficient of restitution of a golf club face of claim 5, wherein the high modulus adhesive comprises cyanoacrylate.

7. The method of determining the coefficient of restitution of a golf club face of claim 5, further comprising the step of applying a second mass to the accelerometer.

8. The method of determining the coefficient of restitution of a golf club face of claim 7, wherein the second mass is applied to the accelerometer with a high modulus adhesive.

9. The method of determining the coefficient of restitution of a golf club face of claim 8, wherein the combined weight of the first and second masses is about the mass of a golf ball.

10. The method of determining the coefficient of restitution of a golf club face of claim 1, wherein the first impact force imparted to the club face is applied approximately normal to the club face.

11. The method of determining the coefficient of restitution of a golf club face of claim 10, wherein the first impact force imparted to the club face is applied with an impact hammer.

12. The method of determining the coefficient of restitution of a golf club face of claim 1, further comprising the step of calculating the inertance of the club face over a frequency range.

13. The method of determining the coefficient of restitution of a golf club face of claim 12, wherein the frequency range is from about 0 hz to about 6000 hz.

14. The method of determining the coefficient of restitution of a golf club face of claim 13, wherein the frequency range is from about 1000 hz to about 5000 hz.

15. The method of determining the coefficient of restitution of a golf club face of claim 14, wherein the frequency range is from about 1000 hz to about 3000 hz.

16. The method of determining the coefficient of restitution of a golf club face of claim 1, further comprising the step of imparting additional impact forces to the club face, wherein the step of measuring the first primary resonant frequency comprises using an average of the impact forces.

17. The method of determining the coefficient of restitution of a golf club face of claim 1, further comprising the step of imparting additional impact forces to improve measurement accuracy.