Golf club head

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention relates to a metal wood golf club head, in particular, during a strike, the head and face plate are stiffened to reduce the bias of the face plate and increase the speed of the ball. is there.

【0002】

It is about.

【0003】

[Conventional technology]

Nowadays, most golf clubs of the type called wood have a hollow structure, some are fiber reinforced plastics, and most are molded by metal casting. Normally, it is desirable to make the club head large enough for practical use, but the size of the head is limited because the wall thickness is too thin to manufacture and the structure of the head becomes brittle due to a large inertial load. Will be done. In addition, as the structural rigidity of the club head increases, so does the speed of the ball.

【0004】

Nowadays, metal wood heads are usually cast from stainless steel, with a thin wall thickness, a slightly thicker face, and usually with large holes in the bottom. A thin sole plate is welded into this hole to complete the construction of the cast metal wood head. These are commonly referred to as metal wood. The present invention can also be applied to those formed by the structure of a fiber reinforced composite. Wood is not applicable to homogeneous structures such as wood and plastics, but is similarly applicable to woods manufactured in hollow structures using other materials such as graphite fiber reinforced plastics.

【0005】

Most hollow heads are filled with foam. Such foam padding is structurally negligible, is effective in controlling sound at impact, and is useful for final fine adjustment of the weight of the head.

【0006】

[Problems to be Solved by the Invention]

The metal wood head usually has a hollow structure with a wall thickness of about 1.02 cm (0.40 inch) and a face thickness of about 0.25 cm to 0.31 cm (0.10-0.12 inch). As the volume of this structure increases, the mass moment of inertia around all axes of rotation increases. This reduces the negative impact on direction and distance in the case of an off-center hit. There is a limit to the maximum volume, as increasing the volume significantly will increase the weight, or reducing the wall thickness will make it less durable to very large impacts and unsatisfactory casting. ..

【0007】

During impact, the golf ball momentarily flattens against the club face, making circular contact with a diameter of approximately 1.91 cm (3/4 inch). The surface of the club head is also distorted, but the head is very small due to its stronger structure compared to the ball. It takes a lot of energy to deform the ball and club head. If this deformation energy (potential energy) is not converted to potential energy at impact, the ball will move away from the club at a correspondingly reduced velocity. The stronger structure of the club solves this problem because it reduces deformation and also reduces potential energy storage. If it's completely rigid and doesn't deform, the problem goes away as far as the club head is concerned. The deformation of the ball is, of course, different from the problem of club head design.

【0008】

The issue of stiffness of golf club heads has traditionally been recognized and has been manufactured to increase stiffness without significantly affecting the weight of the club head.

【0009】

[Means for solving problems]

The present invention relates to a structure, manufacture and assembly method of a hollow golf club head cast and molded with a thick metal frame having a substantially flat strike surface.

【0010】

The thick part of the normal structure, which curves in all directions and supports the face, is preferably corrugated to prevent failure due to distortion, resulting in a skeleton structure that is approximately straight in the load-bearing direction at the impact of the ball. Will be replaced. Waveforms are preferable, but they are complicated to manufacture. In general, a simpler shape that simply forms a curve and is a straight skeleton in the load-bearing direction is preferable to a corrugated shape in the lateral direction. Such a structure is more robust to normal loads due to the impact of the ball on the face. Since the thick portion according to the design of the present invention is manufactured by welding or brazing a metal plate material at a predetermined position, it is possible to avoid the difficulty of manufacturing a thin thick portion.

【0011】

If the face is made of fiber reinforced plastic, the skeleton is also made of a similar material and adhered. When manufactured according to the structure of the present invention as a portion of the face, the process of bonding can be minimized. In addition, a plastic skeleton can be used on the outside and can be coated on an inner shape that is not commonly used for a more traditional outer shape.

【0012】

The word "rigidity" is not always the same as rigidity or strength. Rigidity refers to structural strength. The club head can also be made of a harder material so that it deforms more easily. It can also be made of a less rigid but stronger (resistant to permanent deformation) material.

【0013】

The structure of the present invention is designed to be lighter than a conventional curved skeleton structure. The skeleton mass saved by this is efficiently distributed to the rearmost end of the club head. Therefore, the most important moment of inertia increases. The sweet spot will also be larger, which means that the club will be more tolerant of off-center hits.

【0014】

The present invention is not limited to a thin wall structure, but is stronger and more rigid.

【0015】

The present invention is described by reference to and exemplifying the accompanying drawings.

【0016】

[Example]

One of the golf heads of a preferred embodiment of the present invention, typically represented by 10, comprises a housing 11 having a face plate 14 having a strike face 16 hitting a ball and a sole plate 12 while swinging a club. It becomes. The housing 11 is further secured to a rear face plate and further includes a shell wall 20, which will be described later. The shell wall 20 extends rearward from the face plate and is fixed to the rear end of the head 10 or a mass block on the locus of the head. The rear wall 24 is secured to the mass 22 and is used to support the outer cover 28. The neck or hosel 30 is supported on the shell wall, and the sole plate and club shaft 31 are attached to the neck or hosel 30.

【0017】

The face plate 14 is joined to the rear mass 22 of the club head by a shell wall 20 and a sole plate 12 to form a shell structure 20. As shown, the shell wall 20 is a normally conical wall surrounded by a sole plate 12 to form the shell structure 40. The shell wall 20 includes a top wall element 32 and first, second and third wall elements 34, 36, 38, respectively, as shown. The shell wall element and the sole plate 12 are joined together at adjacent points so that their ends can be glued together for silver soldering, brazing, welding, or rigid assembly. By using the material of, it is bonded to the face plate 14 and the back mass 22 respectively.

【0018】

It is also possible to manufacture the shell wall element and sole plate from a single sheet to reduce the required bonding of the ends. Alternatively, the elements of the shell structure 40 may be cast or formed into two or more units to join.

【0019】

The total mass saved by the weight reduction of the shell structure is not so concentrated behind the mass block 22 of the solid block. If desired, the shell wall, sole plate and face plate can be made heavier and the mass block 22 can be removed. In this case, the rear end of the housing structure may be the end point at some point, and the rear end may be open or, like a conventional club head, a rounded rear end.

【0020】

4 and 5 are the usual conical shapes of the shell structure 40, and compared to the shell wall 20 and the sole plate 12, the shell structure is not a cone with a normal circular cross section. The conical shape of the shell structure is a non-circular cross section. These cross sections are not geometrically similar in shape. When made of metal, the shell structure is formed from a flat member by bending with little metal stretching.

【0021】

The shell wall element 20 is preferably formed into a waveform, and as shown by the shell wall element 32, the long axes of the waveform are basically arranged in the direction between the front end and the rear end of each element. As best shown in FIGS. 4, 5 and 6, the length of the major axis of the waveform is along a straight line in a plane approximately perpendicular to the strike plane. The purpose of this is to improve the compressive force of the entire shell structure and shell wall elements for the loads that the shell structure must withstand during the impact of the ball on the front face 16 of the face plate 14.

【0022】

As shown in FIG. 1, the shaft 31 is properly coupled to the neck or hosel 30. The neck 30 is attached to a shell structure including the shell wall element 32 or, if desired, to another shell wall element and the sole plate 12 by a desired method such as welding, brazing, or gluing. One such bond is at point 42 at the top of the shell structure and the other is at 44 at the top of the sole plate 12. The neck or hosel 30 ends at the sole plate and / or the lower part of the shell wall, exemplified in FIG. 3, extends through the sole plate, if desired.

【0023】

This internal shell structure, which serves as the main support for the faceplate, is preferably covered by a cover 28 and sandwiched between the outer edge of the rear wall 24 and the outer edge of the faceplate 14. And is strongly supported. The cover 28 is then further coupled to the support wall and plate, if desired.

【0024】

It is highly desirable that the cover 28 be rigid and tightly coupled with the rest of the housing elements of the head. If the cover 28 is made of a slightly soft and elastic material, it will not give the ball as much kinetic energy as the rigid cover at impact. This reduction in stiffness reduces the velocity of the ball at a given impact or swing. Plate-like metals or fiber-reinforced plastics, such as the recently available graphite fiber-reinforced plastics, are good materials. The inside of the cover may be filled with foam if desired.

【0025】

An enlarged view of the joint between the cover 28 and the rear wall or plate 24 is shown in FIG. This demonstrates typical bonding techniques for both the front and rear ends of the cover. The shoulder 45 is provided to receive the edge of the cover 28 for easy engagement and a smooth outer shape, while hiding the slight imperfections in the shape of the cover 28 or the rear wall 24. A preferred fit between the cover 12 and the rear wall 24 is shown in 46, where both parts are arranged in place with each other. Further, or alternative, for alignment purposes, tongue-shaped and grooved structures are also used as elements of the joint end, as shown by the dotted line at 47. As an alternative to the curved shell structure of the cover 28, it can also be made of reasonably strong and lightweight foam material.

【0026】

A detailed enlarged view of the cover 28 and its connection to the shell structure is shown in FIG. 7 as an example of its modification. Unlike the previous embodiment, it contains the sticky filling shown in 48 and is preferably formed of a rubber material or the like.

【0027】

The optimum foam filling between the shell structure consisting of the shell wall 20 and the sole plate 12 and the cover 28 is indicated by 50. Means of soldering, welding and other bonding of shell wall elements 34 (40) to the sole plate 12 are indicated by 52.

【0028】

The coupling at the ends of the cover 28 shown in FIG. 7 produces no structural load during impact. Therefore, one simple design is to make an open bond and fill the required intermediate space with the padding material 48. This makes it possible to respond to design changes. Foam 50 can also be used between the cover 28 and the shell structure.

【0029】

Improvements to the strong and rigid club heads according to the present application are obtained from the schematic views shown in FIGS. 9 and 10. FIG. 9 is a diagram showing the strike face as a simple model. Figure 9 shows a schematic model for the strike face. The strike face is shown as plane 55. Shown as the height of the strike face, the top and bottom edges of the metal wood face face plate are generally 4.06 cm (1.60 inch) apart as shown. The conventional outer shell of the club head is significantly thinner than the face plate and is attached to the outer edge of the face plate. The model simply shows 56 at the top of the faceplate and 57 at the bottom, and the bending stiffness of the outer shell of a conventional club is low. The impact force of a golf ball is approximated as a concentration force F as shown in the figure.

【0030】

FIG. 10 also shows a schematic model, but the present invention is shown as 60. As is commonly shown in FIGS. 4 and 5, the top of the conical shell structure, indicated by 20, is 61, approximately 0.64 cm (0.25 inch) below the top edge of the face plate (and strike face). It is attached with. Since the sole plate 12 must be placed on the grass, the attachment of the bottom of the shell structure indicated by the sole plate 12 is at the bottom of the face plate indicated by 62, and the shell structure is from the top and end ends. Can be mounted somewhat inward.

【0031】

These schematic models make it easy to calculate and compare the deflection in each case. In FIG. 10, it is self-evident that it is only 60.1% of the deflection in FIG. The stress can also be easily calculated. The bending stress of the face in FIG. 10 is only 71.2% of the bending stress in FIG.

【0032】

The shell wall 20 is preferably at least 0.38 cm (0.15 inch), or at least inside the edge of the strike face at 10% of the height of the strike face. In a preferred embodiment, it is at least half the perimeter of the entire shell structure with space inside at least 10% of the maximum supported height of the strike face. The suitable portion is about 16% of the height as shown in FIG. The efficient limit of space inside the edges is about 20% of the face height. In practice, a ratio as in the present application seems to be more preferable. The reason is that the force of the ball is not a single point, but extends over a circular area of 1.91-2.54 cm (0.75-1 inch). This is because the space between the support members shown in FIG. 10 is much larger than the space shown in FIG. 9, and the deflection and stress are smaller than the configuration shown in FIG. Another reason is that the conventional shell is curved and deflects outward at impact, causing considerable deflection. The conical shell of the present invention is more robust to such loads and produces little deflection.

【0033】

The mass block 22 is usually formed of metal or other dense material. Since the neck and shaft mounting elements are firmly fixed to the shaft configuration, the rigidity of the shaft configuration is sufficient for the maximum amount of energy transmitted to the ball when the golfer grips the shaft and swings. It becomes effective for.

【0034】

Although the present invention has been described by preferred embodiments, the present invention shall be included in the scope of the present invention as long as it is recognizable to those skilled in the art and does not exceed the spirit and scope of the present invention.

[Simple explanation of drawings]

[Figure 1]

It is a front view of the golf club head of this invention.

[Figure 2]

It is a cross-sectional view along line 2-2 of FIG.

[Fig. 3]

It is a cross-sectional view along the line 3-3 of FIG.

[Fig. 4]

It is a cross-sectional view taken along the line 4-4 of FIG. 3 with the outer cover removed.

[Fig. 5]

It is a cross-sectional view taken along the line 5-5 of FIG. 3 with the outer cover removed.

[Fig. 6]

It is a cross-sectional view taken along the line 6-6 of FIG. 3 with the outer cover removed.

[Fig. 7]

It is a breaking enlarged view which showed the modification of this invention for connecting a cover to a shell structure.

[Fig. 8]

FIG. 3 is an enlarged view showing a typical connection between the rear wall and cover of a golf club head.

[Fig. 9]

It is the schematic which approximated the load, bending and stress applied on the face of a normal golf club head.

[Fig. 10]

It is the schematic which approximated the load, bending and stress applied on the face of the golf club head of this invention.

[Explanation of symbols]

11 Housing 12 sole plate 14 face plate 16 strike face 20 shell wall 22 lump blocks 24 Rear wall 28 cover