Multiple Material Iron-Type Golf Club Head

Abstract

A golf club head includes a perimeter member made of high density material and a face plate insert made of lower density material. In one embodiment, the face plate insert is formed by applying a shell member to a core member so that the shell member encases the core member. Preferably, the shell member is made by electrodepositing a nanometal having a grain size between 10 and 50 nanometers onto the core member.

Description

BACKGROUND OF THE INVENTION

This invention relates generally to golf equipment and, in particular, to golf club heads.

Iron-type golf clubs are intended primarily for second and later shots rather than tee shots. Often they are used for hitting shots from bare ground or sand as well as from turf. Accordingly, conventional iron-type golf clubs are designed so that the club head and, in particular, the sole of the club head are made of a durable material such as iron, stainless steel or like. It is generally desirable for an iron-type golf club head to have perimeter weighting to increase its moment of inertia to resist twisting. It is also desirable for an iron-type golf club head to have a low center of gravity to enhance the ability of the club head to launch the golf ball in an appropriate trajectory and for the club head to be forgiving on off-center hits. Conventional iron-type golf clubs accomplish some of these goals through the use of cavity back club heads, tuning ports in the club heads and, more recently, lightweight forged or rolled titanium club head faces attached to heavier perimeter members.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a golf club head incorporating features of the present invention;

FIG. 2 is a cross-sectional view of one embodiment of a face plate insert according to the present invention;

FIG. 3 is a cross-sectional view of the club head of FIG. 1 taken along line 3-3;

FIG. 4 is a cross-sectional view, similar to FIG. 2, of another embodiment of the face plate insert; and

FIG. 5 is a cross-sectional view, similar to FIG. 3, of a club head including the face plate insert of FIG. 4.

DESCRIPTION OF THE INVENTION

The drawing figures are intended to illustrate the general manner of construction and are not necessarily to scale. In the detailed description and in the drawing figures, specific illustrative examples are shown and herein described in detail. It is understood, however, that the drawing figures and the detailed description are not intended to limit the invention to the particular form disclosed, but are merely illustrative and intended to teach one of ordinary skill how to make and/or use the invention claimed herein and for setting forth the best mode for carrying out the invention.

With reference to FIGS. 1-3, an iron golf club head 10 incorporating features of the present invention is preferably composed of two main components, a perimeter member 12 and a face plate insert 14. The perimeter member 12 is preferably composed of a relatively dense material such as stainless steel, carbon steel, beryllium-copper, or other material having a density of least 7.0 grams per cubic centimeter. The perimeter member has a sole wall 16, a heel wall 18 extending upwardly from heel end 20 of sole wall 16, a toe wall 22 extending upwardly from toe end 24 of sole wall 16, and a top wall 26 extending from an upper end 28 of heel wall 18 to an upper end 30 of toe wall 22. Perimeter member 12 further comprises a hosel 32 having a hosel bore 34 for receiving a golf club shaft (not shown).

Face plate insert 14 is preferably formed of a core member 36 and a shell member 38 that encases core member 36. Preferably, core member 36 is composed of a material such as aluminum, thermoplastic, thermosetplastic or foam metal having a bulk density of less than 2.7 grams per cubic centimeter. Core member 36 is preferably a solid prism having substantially the same shape as finished face plate insert 14 but smaller in overall size. Core member 36 preferably has a thickness alpha (a) in the range of 0.025 to 0.040 inches, and preferably between 0.035 and 0.040 inches.

Shell member 38 comprises a metallic coating that fully encases core member 36. Preferably, shell member 38 comprises a nickel iron nanometal having a grain size on the order of 10 to 50 nanometers. Shell member 38 comprises a front wall 40, a rear wall 42 and a perimeter wall 44. Front wall 40 has a front surface 47 arranged for impacting a golf ball. Preferably, front wall 40 has a thickness beta (β) between 0.030 and 0.050 inch, rear wall 42 has a thickness gamma (γ) between 0.015 and 0.025 inch, and perimeter wall 44 preferably has a thickness delta (δ) between 0.015 to 0.030 inch.

Shell member 38 may be sintered onto core member 36 to form face plate insert 14, however, shell member 38 is preferably applied to core member 36 by an electroplating or electroforming process such as the electroplating process for applying nanometals practiced by Power Metal Technologies, Inc. of Carlsbad, Calif. This process applies coatings that are in excess of 0.010 inches in thickness as opposed to conventional chrome and other protective coatings which are typically less than 0.001 inch thick or less than 1% of the thickness of the part being coated. All of the thicknesses β, γ and δ are at least 1% as thick, and preferably at least 10% as thick, as the thickness α of core member 36. As can be determined from an examination of FIG. 2, face plate insert 14 has an exceptionally high area moment of inertia as a result of the displacement between front wall 40 and rear wall 42. Consequently, a face plate insert constructed in accordance with the teachings of the present invention is lighter, stiffer and yet more forgiving than prior art face plate inserts.

Face plate insert 14 further includes a plurality of grooves 46 disposed in front wall 40. Grooves 46 are preferably U-shaped in cross-section with substantially vertical walls meeting the front surface 47 of face plate insert 14 along a fillet having a radius of 0.010±0.001 inch. Because front wall 40 is formed by an electrodeposition process, rather than casting, the tolerance on the U-shaped grooves 46 can be held to these close tolerances without the necessity of secondary machining.

As shown in FIG. 3, face plate insert 14 may be attached to perimeter member 12 by any conventional means but in the illustrative embodiment is attached to perimeter member 12 by placing face plate insert 14 into a recess 48 formed in perimeter member 12 until it comes to rest against ledge 50. Recess 48 is formed by the sole, heel, toe and top walls 16, 18, 22 and 26, respectively, of perimeter member 12. A deformable lip 52 is then deformed until it presses against shell front wall 40 to form a crimp joint that permanently retains face plate insert 14 in place. Face plate 14 may, however, be attached by unconventional means such as nanobonding in which dissimilar metals are bonded on a submicroscopic level.

Referring to FIGS. 4 and 5, the face plate insert 14 has been replaced by a face plate insert 14A. It will be understood that, in the face plate insert 14A, the core member 36A is sandwiched between front and rear walls 40A, 42A of a shell member 38A. The perimeter wall 44 of the face plate insert 14 has been removed from the face plate insert 14A.

Although certain illustrative embodiments and methods have been disclosed herein, it will be apparent from the foregoing disclosure to those skilled in the art that variations in modifications of such embodiments and methods may be made without departing from the spirit and scope of the invention. For example, although the illustrative embodiment discloses a single solid core, multiple cores and/or hollow cores are considered within the scope of the invention. Accordingly, it is intended that the invention should be limited only to the extent required by the appended claims and the rules and principles of applicable law.

Claims

1. A golf club head comprising:

a perimeter member including a sole wall, a heel wall extending upward from a heel end of said sole wall, a toe wall extending upward from a toe end of said sole wall, and a top wall extending from an upper end of said heel wall to an upper end of said toe wall;

said heel, toe, sole and top walls cooperating to form a recess; and

a face plate insert received in said recess and attached to said perimeter member, said face plate insert including a core member having a first predetermined thickness and a shell member encasing said core member, said shell member having a second predetermined thickness that is at least 1% as thick as the first predetermined thickness, said shell member having a front surface arranged for impacting a golf ball.

2. The golf club head of claim 1, wherein the second predetermined thickness is at least 10% as thick as the first predetermined thickness.

3. The golf club head of claim 1, wherein said perimeter member is made of a first material having a first density and wherein said core member is made of a second material having a second density that is less than said first density.

4. The golf club head of claim 1, wherein said core member is made of nonmetallic material.

5. The golf club head of claim 1, wherein said core member is made of metallic material.

6. The golf club head of claim 1, wherein said shell member is made of a nanometal having a grain size between 10 and 50 nanometers.

7. The golf club head of claim 6, wherein the nanometal is electrodeposited onto the core member.

8. The golf club head of claim 6, wherein the nanometal is sintered onto the core member.

9. The golf club head of claim 1, wherein said shell member comprises a front wall having a thickness between 0.030 and 0.050 inch.

10. The golf club head of claim 9, wherein said shell member comprises a rear wall having a thickness between 0.015 and 0.025 inch.

11. The golf club head of claim 10, wherein said shell member comprises a perimeter wall having a thickness of at least 0.015 inch.

12. The golf club head of claim 1, wherein said face plate insert is attached to said perimeter member by a crimp joint.

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

the front surface of said shell member has a plurality of U-shaped grooves formed therein; and

each of said U-shaped grooves has a first side wall and a second side wall, said first and second side walls intersecting said front surface along a fillet having a radius of 0.010 inch held to a tolerance of ±0.001 inch.

14. A method of manufacturing a golf club head comprising:

providing a perimeter member made of a first material having a first density, said perimeter member having a sole wall, a heel wall extending upward from said sole wall, a toe wall extending upward from said sole wall, and a top wall extending from an upper end of said heel wall to an upper end of said toe wall, said heel, toe, sole and top walls cooperating to form a recess;

forming a core member from a second material having a second density that is less than said first density, said core member having a predetermined thickness;

encasing said core member in a shell member to form a face plate insert, said shell member having a predetermined thickness that is at least 1% as thick as said predetermined thickness of said core member, said shell member further including a front surface arranged for impacting a golf ball;

mounting said face plate insert in said recess; and

attaching said face plate insert to said perimeter member.

15. The method of claim 14, wherein the core member is made of non-metallic material.

16. The method of claim 14, wherein the shell member is made of nanometal having a grain size between 10 and 50 nanometers.

17. The method of claim 16, wherein the nanometal is applied by electrodeposition.

18. The method of claim 16, wherein the nanometal is applied by sintering.

19. The method of claim 14, further comprising forming a plurality of grooves in the front surface of the shell member with each of the grooves having a U-shaped cross section with a first side wall and a second side wall, said first and second side walls intersecting said front surface along a fillet having a radius of 0.010 inch held to a tolerance of ±0.001 inch.

20. The method of claim 14, wherein attaching said face plate insert to said perimeter member comprises using a crimp joint formed by deforming a lip on said perimeter member against the shell front surface.

21. The golf club head of claim 3, wherein said first density is at least 7.0 grams per cubic centimeter and wherein said second density is less than 2.7 grams per cubic centimeter.

22. The method of claim 14, wherein said first density is at least 7.0 grams per cubic centimeter and wherein said second density is less than 2.7 grams per cubic centimeter.

23. A golf club head comprising:

a perimeter member including a sole wall, a heel wall extending upward from a heel end of said sole wall, a toe wall extending upward from a toe end of said sole wall, and a top wall extending from an upper end of said heel wall to an upper end of said toe wall;

said heel, toe, sole and top walls cooperating to form a recess; and

a face plate insert received in said recess and attached to said perimeter member, said face plate insert including a core member having a first predetermined thickness and a shell member, said core member being sandwiched between front and rear walls of said shell member, said shell member having a second predetermined thickness that is at least 1% as thick as the first predetermined thickness, said shell member front wall having a front surface arranged for impacting a golf ball.

24. The golf club head of claim 23, wherein the second predetermined thickness is at least 10% as thick as the first predetermined thickness.

25. The golf club head of claim 23, wherein said perimeter member is made of a first material having a first density and wherein said core member is made of a second material having a second density that is less than said first density.

26. A method of manufacturing a golf club head comprising:

providing a perimeter member made of a first material having a first density, said perimeter member having a sole wall, a heel wall extending upward from said sole wall, a toe wall extending upward from said sole wall, and a top wall extending from an upper end of said heel wall to an upper end of said toe wall, said heel, toe, sole and top walls cooperating to form a recess;

forming a core member from a second material having a second density that is less than said first density, said core member having a predetermined thickness;

sandwiching said core member between front and rear walls of a shell member to form a face plate insert, said shell member having a predetermined thickness that is at least 1% as thick as said predetermined thickness of said core member, said shell member front wall further including a front surface arranged for impacting a golf ball;

mounting said face plate insert in said recess; and

attaching said face plate insert to said perimeter member.