Golf club head

• US 6,551,200 B1
• Filed: 10/19/2001
• Issued: 04/22/2003
• Est. Priority Date: 10/19/2001
• Status: Expired due to Fees

• Current Assignee: Taylor Made Golf Co., Inc.
• Original Assignee: Taylor Made Golf Co., Inc.
• Inventors: Golden, Charles, Anderson, David, Vincent, Benoit, Wahl, Bret
• Primary Examiner(s): Passaniti, Sebastiano
• Application Number:
  US10/057,293
• Time in Patent Office: 550 Days
• Field of Search: 473/290, 473/291, 473/324, 473/334, 473/335, 473/336, 473/337, 473/338, 473/339, 473/349, 473/350, 473/345, 473/256, 473/292, D21/747, D21/748, D21/749, D21/753, D21/759
• US Class Current: 473/349
• CPC Class Codes: A63B 53/005 Club sets
• CPC Class Codes: A63B 53/04 Heads
• 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 53/0458 with non-uniform thickness of the impact face plate
• CPC Class Codes: A63B 53/047 iron-type
• CPC Class Codes: A63B 53/0475 with one or more enclosed cavities
• CPC Class Codes: A63B 60/00 Details or accessories of golf clubs, bats, rackets or the like
• CPC Class Codes: A63B 60/54 with means for damping vibrations

Abstract

A golf club head is provided having enhanced flexibility for launching a golf ball and is most advantageous for use in a wedge-type golf club. An upper portion of the body of the golf club head has a reduced stiffness while a lower portion of the body has reduced stiffness recesses located toward the heel and toe. A low central region supports the head at impact with the golf ball. The relative stiffness in the lower portion of the club head, varying from heel to toe, combines with a top to bottom difference in stiffness to provide enhanced flexibility and selectively increased stiffness for improved performance and feel.

Claims

1. A golf club head comprising:

a body having a planar upper portion, said upper portion having a top edge and a substantially constant thickness, and a rearwardly extending lower portion, said lower portion having a bottom edge, wherein a front surface of said lower portion and a front surface of said upper portion together form a substantially planar striking face having a loft angle measured from a vertical axis, said striking face having a length, and wherein a rear side of said lower portion having at least a first recess adjacent a toe end and at least a second recess adjacent a heel end;

wherein a lateral axis at the junction of said upper and lower portions of said body extends from said toe end to said heel end, with a reference point being defined at a mid portion of said lateral axis, between about 50% and about 75% of the height of the striking face, measured from said bottom edge to said top edge, said reference point being located less than about 70% of the face height if said loft angle is less than about 56 degrees, and wherein a central axis is defined substantially parallel to said lateral axis, at approximately 50% of the face height;

wherein said first recess comprises a first volume and said second recess comprises a second volume, said first and second recesses extending downwardly at least to said central axis, and wherein the portions of the body that define said first and second recesses each have a stifffiess approximately the same as the stiffness of said upper portion, while the remainder of said lower portion has a stiffness at least 50% greater than the stiffness of said upper portion;

wherein a central region of said lower portion, located below said reference point, has a maximum stiffness that is at least about 20 times the stiffness of said upper portion, and wherein regions located below said first and second recesses each have a maximum stiffness at least about 10 times the stiffness of said upper portion, wherein a stiffness zone is located within said central region, at said central axis and extending halfway toward said lateral axis, between said first and second recesses, at least about 10% of the length of said striking face, such that a relative stiffness is established between said central region and said upper portion and between said central region and said first and second recesses.

2. The golf club head of claim 1, wherein said region below said first recess has a maximum stiffness at least about 20 times greater than the stiffness of said upper portion.

3. The golf club head of claim 1, wherein said lower portion comprises at least two recesses located adjacent said toe and at least one recess located adjacent said heel.

4. The golf club head of claim 1, wherein said first and second recesses are open in directions toward said upper portion.

5. The golf club head of claim 1, wherein said first and second recesses are closed in directions toward said upper portion.

6. The golf club head of claim 1, wherein a central region of said lower portion located below said reference point is solid.

7. The golf club head of claim 1, wherein:

a central region of said lower portion of said body, located below said reference point, is hollow; and

said golf club head further comprises a material disposed within the hollow central region that is different from the material of said body of said golf club head.

8. The golf club head of claim 7, wherein the material disposed within the hollow central region has a different density from the density of said body of said golf club head.

9. The golf club head of claim 1, wherein said central region has a length measured along said lateral axis above said stiffness zone that is between about 5 and about 45% of the length of said striking face.

10. The golf club head of claim 9, wherein said length of said central region is between 20 and 40% of the length of said striking face.

11. The golf club head of claim 9, wherein at least 10% of each of said first and second volumes is located below said central axis.

12. The golf club head of claim 1, wherein a toe region of said lower portion of said body, located adjacent to said first recess, has a stiffness at least 95% greater than the stiffness of said upper portion.

13. The golf club head of claim 12, wherein a heel region of said lower portion of said body, located adjacent to said second recess, has a stiffness at least 95% greater than the stiffness of said upper portion.

14. The golf club head of claim 12, wherein said region below said first recess has a maximum stiffness at least 20 times the stiffness of said upper portion.

15. The golf club head of claim 12, wherein at least 20% of each of said first and second volumes is located below said central axis.

16. A golf club head comprising:

a body having a planar upper portion, said upper portion having a top edge and a substantially constant thickness, and a rearwardly extending lower portion, said lower portion having a bottom edge, wherein a front surface of said lower portion and a front surface of said upper portion together form a substantially planar striking face having a loft angle measured from a vertical axis, said striking face having a length, and wherein a rear side of said lower portion having at least a first recess adjacent a toe end and at least a second recess adjacent a heel end;

wherein a lateral axis at the junction of said upper and lower portions of said body extends from said toe end to said heel end, with a reference point being defined at a mid portion of said lateral axis, between about 50% and about 75% of the height of the striking face, measured from said bottom edge to said top edge, said reference point being located less than about 70% of the face height if said loft angle is less than about 56 degrees, and wherein a central axis is defined substantially parallel to said lateral axis, at approximately 50% of the face height;

wherein said first recess comprises a first volume and said second recess comprises a second volume, said first and second recesses extending downwardly at least to said central axis, and wherein the portions of the body that define said first and second recesses each have a thickness approximately the same as the thickness of said upper portion, while the remainder of said lower portion has a thickness at least 25% greater than the thickness of said upper portion, wherein a first rib is located at said toe end of the rear of said lower portion, extending below said first recess, and a second rib is located at said heel end of the rear of said lower portion, extending below said second recess;

and wherein a central region of said lower portion, located below said reference point, has a maximum thickness that is at least about 2.5 times the thickness of said upper portion, and wherein regions located below said first and second recesses each have a maximum thickness at least about 2 times the thickness of said upper portion, wherein a stiffness zone is located within said central region, at said central axis and extending halfway toward said lateral axis, between said first and second recesses, at least about 10% of the length of said striking face, such that a relative stiffness is established between said central region and said upper portion and between said central region and said first and second recesses.

17. The golf club head of claim 16, wherein the thickness of said upper portion is between about 3 mm and about 6 mm.

18. The golf club head of claim 17, wherein the thickness of said upper portion is between about 3.5 mm and about 5 mm.

19. The golf club head of claim 18, wherein the thickness of said upper portion is about 4 mm.

20. The golf club head of claim 16, wherein said junction of said upper and lower portions is curved and said lateral axis is tangential to said junction at said reference point.

21. A golf club head comprising:

a body having a planar upper portion, said upper portion having a top edge and a substantially constant thickness, and a rearwardly extending lower portion, said lower portion having a bottom edge, wherein a front surface of said lower portion and a front surface of said upper portion together form a substantially planar striking face having a loft angle measured from a vertical axis, said striking face having a length, and wherein a rear side of said lower portion having at least a first recess adjacent a toe end and at least a second recess adjacent a heel end;

wherein a lateral axis at the junction of said upper and lower portions of said body extends from said toe end to said heel end, with a reference point being defined at a mid portion of said lateral axis, said reference point being located less than about 75% of the face height, measured from said bottom edge to said top edge, wherein a central axis is defined substantially parallel to said lateral axis, at approximately 50% of the face height;

wherein said first recess comprises a first volume and said second recess comprises a second volume, said first and second recesses extending downwardly at least to said central axis, and wherein the portions of the body that define said first and second recesses each having a stiffness approximately the same as the stiffness of said upper portion, while the remainder of said lower portion has a stiffness at least 50% greater than the stiffness of said upper portion;

wherein the lower portion of said body defines a first rib, said first rib having an upper end located at said toe end of the rear of said lower portion and extending below said first recess, and a second rib, said second rib having an upper end located at said heel end of the rear of said lower portion and extending below said second recess, the upper ends of said first and second ribs extending at least to said central axis;

wherein a central region of said lower portion, located below said reference point, has a maximum stiffness that is at least about 20 times the stiffness of said upper portion, and wherein regions, located below said first and second recesses each have a maximum stiffness at least about 10 times the stiffness of said upper portion, wherein a stiffiiess zone is located within said central region, at said central axis and extending halfway toward said lateral axis, between said first and second recesses, at least about 10% of the length of said striking face, such that a relative stiffness is established between said central region and said upper portion and between said central region and said first and second recesses.

22. The golf club head of claim 21, wherein the upper end of said first rib extends to said lateral axis.

23. The golf club head of claim 22, wherein the upper end of said first rib extends to about 80% of the face height.