Golf club having damping treatments for improved impact acoustics and ball speed

Patent metadata

Field	Value
Publication number	US-10716985-B2
Application number	US-201816117777-A
Country	US
Kind code	B2
Filing date	Aug 30, 2018
Priority date	Jan 17, 2017
Publication date	Jul 21, 2020
Grant date	Jul 21, 2020

Abstract

A golf club head having a damping treatment, such as a viscoelastic polymer, is disclosed. The viscoelastic polymer may be in contact with the rear surface of a striking face of the golf club head. The viscoelastic polymer may have a tangent of delta peak temperature between −70 degrees Celsius and −20 degrees Celsius at a 1 Hz frequency. An elastic modulus (E), in megapascals (MPa), of the viscoelastic polymer has a relationship to a striking face thickness (t), in millimeters (mm), defined Ê≤−14{circumflex over (t)}+305. The elastic modulus (E), in megapascals (MPa), of the viscoelastic polymer has a relationship to an effective stiffness (S) of the striking face, in gigapascals per meter (GPa/m), defined by Ê≤−1.16Ŝ+258.33. The viscoelastic polymer may cover a portion of the rear surface of the striking face or may substantially fill a cavity of the golf club head.

First claim

The invention claimed is:

1. A golf club head comprising:
a body and a striking face forming a hollow cavity; and
a viscoelastic polymer in the hollow cavity and in contact with a rear surface of the striking face,
wherein the viscoelastic polymer has a tangent of delta peak temperature between −70 degrees Celsius and −20 degrees Celsius at 1 Hz, and a tangent of delta peak temperature between 20 degrees Celsius and 50 degrees Celsius at 6 kHz.

2. The golf club head of claim 1 , wherein the viscoelastic polymer substantially fills the hollow cavity.

3. The golf club head of claim 1 , wherein an elastic modulus (E), in megapascals (MPa), of the viscoelastic polymer has a relationship to a striking face thickness (t), in millimeters (mm), defined by Ê≤14{circumflex over (t)}+305, wherein E is a unitless value equal to E/1 MPa and {circumflex over (t)} is a unitless value equal to t/1 mm, and wherein the thickness (t) is one of an average thickness of the striking face and a maximum thickness of the striking face.

4. The golf club head of claim 3 , wherein the relationship between E and t is further defined by Ê≥−33.24{circumflex over (t)}+63.24.

5. The golf club head of claim 1 , wherein an elastic modulus (E), in megapascals (MPa), of the viscoelastic polymer has a relationship to an effective stiffness (S) of the striking face, in gigapascals per meter (GPa/m), defined by Ê≤−1.16Ŝ+258.33, wherein Ê is a unitless value equal to E 1 MPa and Ŝ; is a unitless value equal to S/1 GPa/m, and wherein the effective stiffness S is defined as

S
=

E
face

⁢
t

A

,

wherein E face is the elastic modulus of the material of the striking face, t is a thickness of the striking face, and A is an area of the striking face.

6. The golf club head of claim 5 , wherein the relationship between E and S is further defined by Ê≥−0.33Ŝ+63.33.

7. The golf club head of claim 1 , wherein the polymer comprises at least one of butyl rubbers, butyl rubber ionomers, polyurethanes, polyureas, silicones, acrylate, methacrylates, foamed polymers, epoxies, styrene block copolymers, polybutadiene, nitrile rubber, thermoplastic vulcanizates, or thermoplastic elastomers.

8. A golf club head comprising:
a sole portion;
a topline;
a toe portion;
a heel portion;
a back portion; and
a striking face having a thickness (t), wherein a cavity is defined by the sole portion, the topline, the toe portion, the heel portion, the back portion, and the striking face;
a viscoelastic polymer, having an elastic modulus (E), substantially filling the cavity and in contact with a rear surface of the striking face, wherein the viscoelastic polymer has a tangent of delta peak temperature between 20 degrees Celsius and 50 degrees Celsius at 6 kHz.

9. The golf club head of claim 8 , wherein the elastic modulus (E), in megapascals (MPa), of the viscoelastic polymer has a relationship to the striking face thickness ( 1 ), in millimeters (mm), defined by Ê≤−14{circumflex over (t)}+305, wherein E is a unitless value equal to E/1 MPa and {circumflex over (t)} is a unitless value equal to t/1 mm, and wherein the thickness (t) is one of an average thickness of the striking face and a maximum thickness of the striking face.

10. The golf club head of claim 9 , wherein the thickness (t) is one the average thickness of the striking face.

11. The golf club head of claim 9 , wherein the thickness (t) is the maximum thickness of the striking face.

12. The golf club head of claim 9 , wherein the relationship between E and t is further defined by Ê≥−33.24{circumflex over (t)}+63.24.

13. The golf club head of claim 9 , wherein the thickness (t) is about 1.4-1.9 mm.

14. The golf club head of claim 9 , wherein the thickness (t) is about 1.5 mm.

15. The golf club head of claim 8 , wherein the viscoelastic polymer has a tangent of delta peak temperature between −10 degrees Celsius and 40 degrees Celsius at 1 kHz.

16. The golf club head of claim 8 , wherein the elastic modulus (E), in megapascals (MPa), of the viscoelastic polymer has a relationship to an effective stiffness (S) of the striking face, in gigapascals per meter (GPa/m), defined by Ê≤−1.16Ŝ+258.33, wherein Ê is a unitless value equal to E/1 MPa and Ŝ is a unitless value equal to S GPa/m, and wherein the effective stiffness S is defined as

S
=

E
face

⁢
t

A

,

wherein E face is the elastic modulus of the material of the striking face and A is an area of the striking face.

17. The golf club head of claim 16 , wherein the relationship between E and S is further defined by Ê≥−0.33Ŝ+ 63 . 33 .

18. A golf club head comprising:
a sole portion;
a topline;
a toe portion;
a heel portion;
a back portion; and
a striking face having a thickness (t), wherein a cavity is defined by the sole portion, the topline, the toe portion, the heel portion, the back portion, and the striking face;
a viscoelastic polymer, having an elastic modulus (E), substantially filling the cavity and in contact with a rear surface of the striking face, wherein the viscoelastic polymer has a tangent of delta peak temperature between 20 degrees Celsius and 50 degrees Celsius at 6 kHz,
wherein the elastic modulus (E), in megapascals (MPa), of the viscoelastic polymer has a relationship to the striking face thickness (t), in millimeters (mm), defined by Ê≤−14{circumflex over (t)}+305 and Ê≥−33.24{circumflex over (t)}+63.24, wherein Ê is a unitless value equal to E/1 MPa and t is a unitless value equal to t/1 mm, and wherein the thickness (t) is one of an average thickness of the striking face and a maximum thickness of the striking face, and
wherein the elastic modulus (E), in megapascals (MPa), of the viscoelastic polymer has a relationship to an effective stiffness (S) of the striking face, in gigapascals per meter (GPa/m), defined by Ê≤−33.24{circumflex over (t)}+258.33 and Ê≥−0.33Ŝ+63.33, wherein Ê is a unitless value equal to E/1 MPa and Ŝ is a unitless value equal to S/1 GPa/m, and wherein the effective stiffness S is defined as

S
=

E
face

⁢
t

A

,

wherein E face is the elastic modulus of the material of the striking face and A is an area of the striking face.

19. The golf club head of claim 18 , wherein Ê≤60.

20. The golf club head of claim 19 , wherein the striking face thickness (t) is about 1.5 mm.

Assignees

• Acushnet Co

Inventors

• Golden Charles E
• Franz Michael E
• Hebreo Jonathan
• Comeau Brian

Classifications

• A63B53/0408

  characterised by specific dimensions, e.g. thickness · CPC title

• A63B60/002

  Resonance frequency related characteristics · CPC title

• A63B53/0475

  with one or more enclosed cavities · CPC title

• A63B53/047

  iron-type · CPC title

• A63B60/00

  Details or accessories of golf clubs, bats, rackets or the like · CPC title