JP2005261739A - Golf club head and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club head having high dimensional accuracy, high yield and durability, and a manufacturing method thereof.
A golf club head manufacturing method according to the present invention includes a metal member forming step of separately forming a metal face plate and a metal sole plate, and integrating the face plate and the sole plate; It has a joining step of joining a preform in which a prepreg is pre-shaped to a face plate and a sole plate, and an internal pressure forming step in which these are placed in a mold and subjected to internal pressure molding. The golf club head 10 of the present invention has a metal member in which a metal face plate 11 and a metal sole plate 12 which are separately formed are integrated, and a crown 13 and a sole 14 made of fiber reinforced resin.
[Selection] Figure 1

Description

  The present invention relates to a golf club head composed of a metal member and a fiber reinforced plastic (FRP) member, and a method for manufacturing the same.

A golf club is required to have a golf ball that flies well when the golf ball is hit and has high stability in the direction of flight. Therefore, a golf club head having a low center of gravity, light weight and high strength is required. In recent years, as a golf club head having a low center of gravity, light weight, and high strength, a metal member 55 having a crown 51 and a sole 52 made of FRP as shown in FIG. Has been proposed (for example, see Patent Documents 1 to 3).
Japanese Patent No. 2777309 JP 59-90578 A JP 2002-336389 A

However, the integrally formed metal member has a large size and a three-dimensional and complicated shape, so that it has been difficult to manufacture with high dimensional accuracy. For this reason, mass production of golf club heads using integrally formed metal members results in variations in mass, face angle, dimensions, and center of gravity, resulting in an increase in defective products and a decrease in yield. In addition, when the dimensional accuracy is low, it may deviate from the design, resulting in low adhesion between the integrally formed metal member and the crown or sole, low adhesive strength, and low durability of the golf club head. there were.
The present invention has been made in view of the above circumstances, and provides a golf club head having high dimensional accuracy, high yield and durability, and a method for manufacturing the same, even when a metal member is attached to a face portion and a sole portion. For the purpose.

The golf club head manufacturing method of the present invention includes a metal member forming step of separately forming a metal face plate and a metal sole plate,
A joining step of joining the face plate and the sole plate together, and joining a preform obtained by pre-forming the prepreg to the face plate and the sole plate;
These are arranged in a mold and include an internal pressure molding step of internal pressure molding.
In the golf club head manufacturing method of the present invention, the engaging portion is formed on the face plate and / or the sole plate in the metal member forming step, and the face plate and the sole plate are engaged with the engaging portion in the joining step. Can be engaged.
Further, in the metal member forming step, a flange can be formed on the face plate, and an engaging portion can be formed at the end of the flange.
In the method for manufacturing a golf club head according to the present invention, it is preferable to form a cut in the prepreg in advance before preliminary shaping.
A golf club head according to the present invention is characterized by having a metal member integrally formed with a metal face plate and a metal sole plate, and a crown and sole made of fiber reinforced resin.
In the golf club head of the present invention, it is preferable that the face plate and the sole plate are engaged with each other at an engagement portion formed on at least one of them.
In the golf club head of the present invention, it is preferable that the metal forming the sole plate has a higher specific gravity than the metal forming the face plate.

  In the present invention, since the face plate and the sole plate are separately formed, each of them can be small and simplified in shape, and the dimensional accuracy can be increased even when a metal member is attached to the face portion and the sole portion. Therefore, variations in mass, face angle, dimensions, and center of gravity can be reduced, and yield can be increased. Further, since the dimensional accuracy is increased, the adhesion between the metal member and the crown or sole is increased, and the durability of the golf club head can be increased. Further, since the face plate and the sole plate are integrated, the design is excellent.

An embodiment of a golf club head and a manufacturing method thereof according to the present invention will be described.
FIG. 1 shows a cross-sectional view of the golf club head of this embodiment. The golf club head 10 includes a metal face plate 11 having a face 21 and flanges 22a and 22b formed extending from the edge of the face 21 to the opposite side of the striking surface 31, and a metal sole plate. 12 and a crown 13 and a sole 14 made of fiber reinforced resin.
Here, the crown 13 is a portion excluding the face plate 11, the sole plate 12 and the sole 14, and the sole 14 is a portion excluding the face plate 11, the sole plate 12 and the crown 13. It is.

  The golf club head 10 is integrated by engaging a face plate 11 and a sole plate 12 at engaging portions formed respectively. The engaging portion of the face plate 11 in this embodiment is a thin portion 20a formed at the end portion of the lower flange 22a, and the engaging portion of the sole plate 12 is formed at the flange side end portion of the sole plate 12. The thin-walled portion 20b. Further, the thin portion 20a of the face plate 11 and the thin portion 20b of the sole plate 12 correspond to each other shape, and when they are stacked, they are engaged in close contact.

The flanges 22a and 22b of the face plate 11 are joints between the crown 13 and the sole 14. If the length is long, the joint strength between the face plate 11 and the crown 13 or the sole 14 can be increased, but the flanges 22a and 22b. If the length of the golf club becomes longer, the golf club head 10 becomes heavier. From these points, the preferable lengths of the flanges 22a and 22b are 5 mm to 20 mm, and more preferably 10 mm to 15 mm.
Furthermore, considering the balance between the joining strength of the engaging portion and the weight of the golf club head 10, the preferred length of the engaging portions (thin portions 20a, 20b) is 2 mm to 20 mm.

  The sole plate 12 is formed with a hole 33 for inserting a pressure bag used when the golf club head 10 is manufactured. The hole 33 is preferably a screw hole (this screw hole may be referred to as a “pladder hole”). If the hole 33 is a screw hole, it is easy to close the hole by screwing the screw after the pressure bag is extracted from the screw hole. When a screw having a large specific gravity such as a tungsten alloy is used as a screw to be screwed into the screw hole, the center of gravity of the golf club head is further lowered.

The face plate 11 and the sole plate 12 are separately manufactured by metal casting, forging, or cutting. Examples of the metal material constituting the face plate 11 and the sole plate 12 include a titanium alloy, an aluminum high-strength alloy, and stainless steel. A titanium alloy is preferable in terms of a balance between strength and specific gravity. The face plate 11 and the sole plate 12 may be made of the same material or different materials. In particular, since the center of gravity of the golf club head can be easily lowered, the sole plate 12 has a specific gravity higher than that of the face plate 11. It is preferable to use a larger one. For example, the sole plate 12 can be made of stainless steel, and the face plate 11 can be made of titanium alloy.
Furthermore, since the adhesive strength of the face plate 11 and the sole plate 12 is increased, the surface to be bonded to the crown 13 or the sole 14 is roughened in advance by blasting or the like, so that the surface roughness Ra becomes 1 μm to 20 μm. It is preferable that For the same reason, it is preferable that the face and the surface of the sole plate that are bonded to the crown 13 or the sole 14 are degreased with methyl ethyl ketone or acetone.

The crown 13 and the sole 14 are obtained by laminating a plurality of fiber reinforced resin layers and integrating them. For example, the reinforcing fibers aligned in one direction are laminated on a layer oriented in a direction orthogonal to the striking surface 31 (0 °) and a layer oriented in a direction parallel to the striking surface 31 (90 °). In addition, the form of the reinforcing fiber forming the fiber reinforced resin is not limited to that arranged in one direction but may be a woven fabric.
Examples of the matrix resin contained in the fiber reinforced resin that forms the crown 13 and the sole 14 include epoxy resins, vinyl ester resins, unsaturated polyester resins, polyimide resins, maleimide resins, and phenol resins. Examples of the reinforcing fiber include carbon fiber, glass fiber, aramid fiber, boron fiber, silicon carbide fiber, high-strength polyethylene, PBO fiber, and stainless steel fiber. Among these reinforcing fibers, carbon fibers are preferable from the viewpoint of strength.

  The face plate 11 and the crown 13 and the sole 14, and the sole plate 12 and the sole 14 are joined via a film adhesive 16. Since the film adhesive 16 has a uniform thickness and is less likely to cause spots, a stable adhesive strength can be obtained.

Here, as resin which comprises the film adhesive 16, an epoxy resin, a polyester resin, an acrylic resin, etc. are mentioned, An epoxy resin is preferable at the point of adhesive strength. More preferably, the epoxy resin composition contains an elastomer component in addition to the epoxy resin component and the curing agent component. Examples of the elastomer component include Carboxy-Terminated Butadiene Acrylonitrile Copolymer (CTBN).
Furthermore, the handleability and adhesiveness of the film adhesive 16 improve because the film adhesive 16 contains the base material which consists of a nonwoven fabric or a woven fabric. Furthermore, when stress is applied to the adhesive layer after curing, even if a minute crack occurs, the progress of the crack can be suppressed, so that the fracture strength of the adhesive layer can be improved.
Examples of the nonwoven fabric and woven material used for the film adhesive 16 include, but are not limited to, polyester fiber, nylon fiber, aramid fiber, acrylic fiber, and glass fiber.

  The face plate 11 and the crown 13 and the sole 14 and the sole plate 12 and the sole 14 may be joined with a liquid adhesive. However, in the three-dimensional shape like the golf club head 10, the liquid adhesive is uniformly thick. It is necessary to pay sufficient attention to applying in width. Adhesive coating spots and thickness spots cause a decrease in adhesive strength, making it difficult to obtain a golf club head having stable strength.

Next, a method for manufacturing the above-described golf club head 10 will be described.
First, in the metal member forming step, a metal face plate having a face and a flange and a metal sole plate disposed on the bottom surface of the golf club head are separately obtained by casting, forging or cutting. At that time, a step is formed on the inner surface side of the end of the lower flange of the face plate to provide a thin portion (engagement portion), and a step is formed on the outer surface side of the flange side end of the sole plate to form a thin portion (engagement). Part). Further, the thin plate portion of the face plate and the thin plate portion of the sole plate are shaped so as to correspond to each other.
In the preform manufacturing step, the first preform is manufactured by pre-forming the prepreg into the shape of the sole, and the second preform is manufactured by pre-forming the prepreg into the shape of the crown. When producing the first preform, an opening is formed so as not to block the screw hole formed in the sole plate. Here, the pre-shaping means that a plurality of prepregs are stacked, integrated with the adhesive force, and shaped into an approximate shape close to the final crown or sole.

  In the production of a preform, it is preferable to form a cut in the prepreg before preliminary shaping. If the prepreg is pre-cut, when the laminated prepreg is pre-shaped, by bonding the ends of the cut together, it becomes easier to form a curved sole or crown shape, It is also possible to form a deep drawing shape.

Next, in the joining step, as shown in FIG. 2, after the thin portion 20b of the sole plate 12 is superimposed on the thin portion 20a of the face plate 11, the bottom surface of the first preform 41 and the top surface of the sole plate 12 are Are joined via the film adhesive 16, and the first preform 41 and the lower flange 22 a of the face plate 11 are joined via the film adhesive 16. Then, the face plate and the sole plate are integrated while the face plate 11 and the sole plate 12 are fixed to the sole 12.
Next, as shown in FIG. 3, the pressure bag 35 is inserted from the hole 33 of the sole plate 12. Examples of the material of the pressure bag 35 include silicone rubber, nylon, and polyester. Next, the second preform 42 and the upper flange 22 b of the face plate 11 are bonded via the film adhesive 16 while the second preform 42 is placed on the first preform 41. In this way, a molded product precursor 45 is obtained.

  Next, in the internal pressure molding step, the molded product precursor 45 is subjected to internal pressure molding. Specifically, as shown in FIG. 4, a molded product precursor 45 is placed in a mold 48 composed of an upper mold 46 and a lower mold 47, the mold is closed, and then air is applied to the pressure bag 35. To inflate the pressure bag 35. Then, while pressing the first preform 41 and the second preform 42 against the mold 48 by the inflated pressure bag 35, the mold 48 is heated to a temperature corresponding to the curing temperature of the matrix resin, and each preform is heated. The matrix resin for reforming is thermoset and molded. By this molding, the first preform 41 becomes a sole, and the second preform 42 becomes a crown.

  Next, the mold is opened, the obtained molded product is taken out, and the pressure bag is taken out from the hole. Finally, a tungsten alloy screw is screwed into the hole of the sole plate, and the screw hole is closed to obtain a golf club head. Here, the screw screwed into the screw hole of the sole plate preferably has a large specific gravity because the golf club head can have a lower center of gravity, and examples thereof include a tungsten alloy or a copper alloy.

In the embodiment described above, since the face plate and the sole plate are separately molded, each of them is small in size and simplified in shape, and even when a metal member is attached to the face portion and the sole portion, dimensional accuracy is achieved. Can be high. Therefore, during mass production, variations in mass, face angle, dimensions, and center of gravity are reduced, and yield is increased. Further, since the dimensional accuracy is increased, the adhesion between the metal member and the crown or sole is increased, and the durability of the golf club head is increased.
Further, since the face plate and the sole plate are engaged with each other by the engaging portions formed respectively, they can be integrated at an accurate position. The design can be enhanced by integrating the face plate and the sole plate.

Note that the present invention is not limited to the above-described embodiments. For example, in the above-described embodiment, the engaging portion is the thin portion formed on the lower flange of the face plate and the thin portion formed on the sole plate, but the shape is such that the face plate and the sole plate can be engaged. I just need it. For example, as shown in FIG. 5, the face plate 11 is not provided with a thin portion (engagement portion), the sole plate 12 is provided with a step, and the step is used as the engagement portion 20c, and the engagement portion 20c and the flange 22a The upper surface may be joined. Further, as shown in FIG. 6, the end surfaces of the sole plate 12 and the face plate 11 can be inclined, and the inclined end surfaces can be used as the engaging portions 20d and 20e. Further, as shown in FIG. 7, the sole 14 may not be provided until it contacts the face 21 but may be provided so as to be joined to a part of the sole plate 12. In this case, the face plate 11 and the sole plate 12 are joined by the film adhesive 16. In the example of FIG. 7, the amount of FRP used is reduced, so the cost is reduced.
Further, in FIGS. 1 to 7, the sole plate is disposed on the upper side of the face plate in the engaging portion, but the vertical relationship between the sole plate and the face plate in the engaging portion may be reversed.
Furthermore, although the fiber reinforced resin part was divided | segmented into two of a crown and a sole, you may divide | segment into three or more. As an example of dividing the preform into three or more, there is an example in which the head body is divided into three parts, that is, a sole, a crown, and a ribbon.

A stainless steel (SUS314) sole plate with a thickness of 1.5 mm in which a screw hole is screwed and a titanium alloy with a flange thickness of 1.5 mm and a face thickness of 2.8 mm The face plate and the face plate were molded separately, and the surfaces to be joined to the sole plate and the face plate preform were roughened by blasting and degreased with acetone.
At the same time, a prepreg impregnated with epoxy resin in carbon fibers aligned in one direction (Pyrofil (registered trademark) TR350 manufactured by Mitsubishi Rayon Co., Ltd.) is used, and the orientation direction of the carbon fibers in each layer is 0 ° / 90 ° / 0. Four layers were laminated so as to have an angle of 90/90, and a first preform was obtained by preliminarily shaping the shape of the sole of the golf club head (thickness: 1.0 mm). In addition, the opening part 33 which does not block | close the screw hole of a sole plate was formed in the 1st preform (refer FIG. 2). In addition, four layers of the prepreg were laminated to obtain a second preform that was pre-shaped into the shape of a crown of a golf club head (thickness 0.7 mm).

Next, as shown in FIG. 2, after the thin portion 20b of the sole plate 12 is superimposed on the thin portion 20a of the face plate 11, the bottom surface of the first preform 41 and the top surface of the sole plate 12 are formed into a film shape. While joining via the adhesive 16, the bottom face of the first preform 18 and the top face of the sole plate 12 were joined via the film adhesive 16. Next, the first preform 18 and the lower flange 22 a of the face plate 11 were joined via the film adhesive 16. In this way, the face plate 11 and the sole plate 12 were integrated.
Subsequently, as shown in FIG. 3, a pressure bag 35 made of silicone rubber was inserted from the screw hole 33 of the sole plate 12. Thereafter, the second preform 42 is placed on the first preform 41, and the second preform 42 and the upper flange 22 b of the face plate 11 are bonded via the film adhesive 16. A molded product precursor 45 was produced.

Next, as shown in FIG. 4, the molded product precursor 45 was placed in a mold 48 including an upper mold 46 and a lower mold 47, and the mold 48 was closed. Next, the pressurization bag 35 is pressurized to 0.2 MPa and expanded, and the mold temperature is set to 130 while the first preform 41 and the second preform 42 are pressed against the mold by the expanded pressurization bag 35. The preformed epoxy resin was cured by heating at 0 ° C. and molded.
The obtained molded product was removed from the mold, and the pressure bag was extracted from the screw hole. Then, a fiberscope (F5D10W manufactured by NISCO Co., Ltd.) is inserted from the screw hole, and the bonding state between the face plate and the first preform and the second preform is observed. It confirmed that it was fully joined.
Thereafter, a tungsten alloy screw was screwed into the screw hole to obtain a final golf club head.

  In this golf club head, the face plate and the sole plate are separate members, and each has high dimensional accuracy. Therefore, variations in mass, face angle, size, and center of gravity can be reduced, and the yield during mass production can be increased. Further, since the dimensional accuracy was high, the adhesion between the metal member and the crown or sole was high, and the durability of the golf club head was high. Specifically, even if a 3000 impact test was performed at a head speed of 50 m / sec, the test had durability to withstand the impact test.

1 is a cross-sectional view showing an embodiment of a golf club head of the present invention. FIG. 3 is a cross-sectional view showing a step of the method for manufacturing the golf club head shown in FIG. 1. FIG. 3 is a cross-sectional view showing a step of the method for manufacturing the golf club head shown in FIG. 1. FIG. 3 is a cross-sectional view showing a step of the method for manufacturing the golf club head shown in FIG. 1. It is sectional drawing which shows the other embodiment of the golf club head of this invention. It is sectional drawing which shows the other embodiment of the golf club head of this invention. It is sectional drawing which shows the other embodiment of the golf club head of this invention. It is sectional drawing which shows the golf club head of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Golf club head 11 Face board 12 Sole board 20a, 20b Thin part (engagement part)
20c, 20d, 20e engaging part

Claims (7)

A metal member forming step of separately forming a metal face plate and a metal sole plate;
A joining step of joining the face plate and the sole plate together, and joining a preform obtained by pre-forming the prepreg to the face plate and the sole plate;
A method of manufacturing a golf club head, comprising: an internal pressure molding step in which these are placed in a mold and subjected to internal pressure molding.   The engagement part is formed in the face plate and / or the sole plate in the metal member forming step, and the face plate and the sole plate are engaged in the engagement portion in the joining step. A method of manufacturing the golf club head according to the description.   3. The golf club head manufacturing method according to claim 2, wherein in the metal member forming step, a flange is formed on the face plate, and an engaging portion is formed at an end of the flange.   The method for manufacturing a golf club head according to any one of claims 1 to 3, wherein a slit is formed in advance in the prepreg before the pre-shaping.   A golf club head comprising: a metal member in which a separately formed metal face plate and a metal sole plate are integrated; and a fiber reinforced resin crown and sole.   6. The golf club head according to claim 5, wherein the face plate and the sole plate are engaged with each other at an engagement portion formed on at least one of them.   7. The golf club head according to claim 5, wherein the metal forming the sole plate has a specific gravity greater than that of the metal forming the face plate.

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