JPS6365882A - Production of golf club set - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a golf club head having an outer shell made of fiber-reinforced plastics (hereinafter abbreviated as FRP), such as a wood club head. Concerning the manufacturing method.

(Prior Art) Conventionally, in manufacturing this type of golf club head, for example, a wood club head, Japanese Patent Publication No. 51-214
As disclosed in Publication No. 36, a raw material for FRP molding such as prepreg (an uncured liquid synthetic material for the matrix is added to the reinforcing fibers) is placed around the core constituent material made of foamed synthetic resin etc. that constitutes the core of the head. A material impregnated with resin and semi-cured if necessary is added by hand, etc. to form the head molding material, and the head molding material of the bracket is placed in the desired mold. A method has been proposed in which the material is obtained by hot pressing.

However, in the above-mentioned conventional method, since the volume of the cavity in the mold is constant depending on the outer circumference of the head, if there is an excess or deficiency in the volume of the head molding material preformed by hand-laying, etc., the FRP molding If the clamping force applied to the raw material varies and is insufficient, in the case of products made by laminating multiple layers of raw materials for FRP molding, problems such as insufficient adhesion between the five layers or air bubbles between the layers or on the surface of the molded product may occur. In addition, in the case of excessive amount, when closing the mold, F R
A part of the raw material for molding is caught between the mating surfaces of the mold, and a flaky substance is formed on the surface of the molded product, which requires a lot of time and effort for surface finishing work after molding, and leads to a decline in quality. Not only that, but by cutting and removing the fibers, some of the reinforcing fibers made of long fiber material may be cut, which may reduce the overall strength of the head.

Therefore, as a means to compensate for these drawbacks of the conventional method, a core component is inserted into the cavity in the mold in advance, and
A gap is formed between the inner circumferential wall surface of the cavity of this mold and the outer circumferential surface of the core component.

This void is usually filled with a bulk molding compound in which reinforcing fibers made of relatively short fibers are mixed or impregnated with a matrix liquid synthetic resin containing a curing agent and a condensing agent, and semi-cured as required. (B.M.
C) or sheet molding compound (SM
A method has been proposed in which the head shell is formed by feeding and hardening a raw material for FRP molding called C).

(Problems to be Solved by the Invention) However, with this type of conventional head molding means, it is difficult to insert and position the core component into the cavity in the mold. In order to maintain a gap between the core component and the outer circumferential surface of the component, multiple spacer members may be provided around the core component, or a support member that supports the core component may be placed externally in the cavity within the mold. However, in the former case, traces of the spacer member will appear on the surface of the molded product, and in the latter case, the spacer member will appear on the surface of the molded product. The raw material inlet inevitably faces the core component positioned in the cavity, and for this reason, the feeding pressure when feeding the raw material for FRP molding acts directly on the core component. , causes misalignment of the core component material, and as a result, F
Not only does it have a negative effect on the strength characteristics of the RP head shell.

It is easy to cause molding defects.

Furthermore, since carbon fiber is mainly used as the reinforcing fiber for FRP that makes up the conventional head outer shell, the head exhibits a black color, resulting in poor aesthetics and resistance to direct sunlight. However, there was a problem in that it had a high heat absorption property, which was disadvantageous.

This invention was made under the above circumstances, and its purpose is to improve the reinforcing fiber structure of raw material for FRP molding, and to improve the feeding pressure when feeding the raw material for FRP molding. It is an object of the present invention to provide a method for manufacturing a golf club head that can avoid influence on core constituent materials.

[Structure of the Invention (Means for Solving the Problems)] In order to solve the above-mentioned problems, the present invention involves forming a predetermined gap around a cavity in a mold with a core component material that can be eluted in advance. A first step of inserting, positioning and fixing the raw material for forming the FRP outer shell into the gap, and feeding the green material for forming the FRP outer shell into the cavity through the hole penetrated toward the cavity in the mold to form the head. A second step for hardening and molding the outer shell molding.
and a third step of eluting the core part constituent material to the outside after hardening and molding the head outer shell molded body.

(Function) That is, the present invention has the above-mentioned configuration, so that a predetermined gap is formed around the cavity in the mold, and the core component material, which can be eluted and has high pressure resistance such as a low melting point alloy, can be used. is inserted, positioned and fixed, and a raw material for molding the FRP outer shell with aramid fibers as reinforcing fibers is fed into the void from the hole penetrated toward the cavity in the mold to harden the head outer shell. After molding, while the core component is eluted to the outside, the core component is held and fixed to the tip of a feeding tube for raw material for FRP outer shell molding, and inserted into a mold and positioned and fixed. As a result, it is possible to avoid the influence on the core component material due to the feeding pressure when feeding the green material for forming the FRP outer shell, and also to strengthen the green material for forming the FRP outer shell. Since aramid fiber cloth or unidirectional bundle of aramid fibers are used as fibers, carbon fiber reinforcement F
It is possible to obtain a head outer shell molded body with a lighter specific gravity and slightly lower elastic modulus than that of RI), which prevents the head surface from appearing black and improves aesthetics. Moreover, since it has excellent vibration damping characteristics, it also provides a softer feel at impact, making it possible to improve the quality of the ball.

(Embodiments) Hereinafter, the present invention will be described in detail with reference to illustrated embodiments.

As shown in FIG. 1, numeral 1 in the figure is a head body of a golf wood club according to the present invention obtained by a manufacturing process described later. This head body 1 is formed of an outer shell 2 made of FRP and a hollow core part 3, and a sole plate serving as a plate-shaped weight member made of a metal material such as brass is provided on the head sole surface 1a. 4 is installed. This sole plate 4 has a protrusion 4a that is fitted to cover a hole 2a that is opened on the head sole surface 1a side of the head outer shell 2 when the hollow core 3 of the head body 1 is molded. ing. In addition, 5 in the figure is a hardened FRP embedded in the FRP outer shell 2 of the ball hitting surface 1b of the head body 1, for example, using carbon fiber as a reinforcing fiber.
Alternatively, a face plate made of ceramics or the like; 6 a back weight member made of a metal material such as brass provided on the back surface 1c of the head body 1; and 7 inserted and fixed into the neck surface 1d of the head body 1. It is a shaft.

That is, in order to eliminate the missing part of the club head according to the present invention described above, as shown in FIGS. 2 to 6, a low melting point alloy that can be eluted into the core component 11 having a shape substantially similar to the shape of the head core is prepared in advance. mold separately.

At the same time, a holding hole 12 is formed in the center of the core component 11 upward from the bottom side corresponding to the head sole side, and a cylindrical FRP made of a metal material or the like is inserted into the holding hole 12. Tip part 13a of raw material tube 13 for molding
By inserting the head core material 11 into the feed tube 13, the core component 11 is held so as not to be displaced (see Fig. 2). The base 13b side of the feed cylinder 13 is inserted into a mold 14.15 consisting of a mold, and the base 13b side of the feeding cylinder 13 is inserted into a mold hole 17 that passes through the mold 14 and the cavity 16 formed by clamping the IS. The outer circumferential surface ILa of the core component 11 and the mold 1 are
4. Position and fix the core component 11 so that a void vX18 corresponding to the thickness distribution of the head shell is formed between it and the inner circumferential wall surface 16a of the cavity 16 of 15 (see FIG. 3). .

At this time, an air vent hole (not shown) that communicates with the void 18 is formed around the base 13b of the feed tube 13 for FRP molding green material held in the mold hole 17 of the mold 14.15 (note that The function of this air vent hole may be achieved by the gap created between the mold hole 17 and the base 13b of the feeding tube 13 even if it is not specially set), or the core component 11 or the mold 14. Hardened FRP on the parts corresponding to the ball hitting surface, back surface, or sole surface of the 15 head.
The face plate consisting of the base plate, weight members, etc., as needed, are placed in a temporarily fixed state.

In this state, the aramid fibers are reinforced by the pushing action of the piston body 19 from inside the base 13b of the FRP molding raw material feed tube 13 that protrudes outside the mold 14.15 as a cylinder. BMC made into fiber
or FRI) raw material 20 for outer shell molding made of SMC is transferred from the tip 13a of the feeding cylinder 13 to the mold 14.15.
The air in the void vX18 is filled while being discharged from the air vent hole (not shown), and hardening and molding is performed (see FIG. 4).

In this way, after the head outer shell molded body 30 is hardened and molded, 11
When the temperature of the mold 14 and IS is raised again to heat the head outer shell molded body 30 as a whole, the core component 11 is melted, and the feeding cylinder 13 is pulled out and removed from the mold 14.15. At the same time, it is eluted to the outside from the mold cavity 17 (see FIG. 5).

Further, after elution of the core constituent material 11 described above.

A sole plate 4 made of a plate-shaped weight member made of a metal material such as brass is attached to a portion corresponding to the sole surface of the head outer shell molded body 30, and a protrusion 4 protrudes from the sole plate 4.
By covering the core constituent material elution hole 30a formed in the portion corresponding to the sole surface of the head outer shell molded body 30 at step a (see FIG. 6).

A head molded product as shown in FIG. 1 is obtained.

According to the above-mentioned manufacturing means according to the present invention,
The tip part 13a of the cylindrical feeding tube 13 for green material for FRP molding is exposed in the mold 14.15, and the core component 11 is supported in a penetrating state on the outer peripheral side of the tip part 13a. The core component 11 is positioned by the fixing means of the feed tube 13 which is held in the mold hole 17 by the clamping action of the mold 14. This is because the raw material 20 for forming the FRP outer shell is fed into the gap 18 for forming the head outer shell formed between the inner circumferential wall surface 16a of the cavity 16 of No. 15 and the outer circumferential surface of the core component 11. The opening of the mouth 13a of the feeding cylinder 13 always faces the inner peripheral wall surface of the mold 14.15, and the pressure when feeding the raw material for FRP molding directly acts on the core component 11. This makes it possible to stably position the core component within the mold.

By the way, the aramid fibers used as reinforcing fibers constituting the raw material 20 for molding the FRP outer shell are cloth or unidirectional bundles with a length of 20 to 50 mm, and these fibers are coated with a liquid synthetic resin for matrix. It is impregnated, semi-cured, and cut, and in order to feed such raw material 20 for forming an FRP outer shell into the gap 18 around the core component 11, the core component is Glass fiber or carbon fiber is wound around the material 11 so that it can be fed into the material, and at the same time, the head body 1 is coated with glass fiber or carbon fiber.
A sole weight member 4, a face surface member 5, and a back weight member 6 are packed and arranged as necessary in corresponding portions of the sole portion 1a, face portion 1b, and back portion 1c, and the head outer shell molded body 30 is formed. It is also possible to attach them together at the same time. Furthermore, in order to elute and remove the core component material 11, a mold hole is opened in a corresponding part of the back IC other than the sole part 1a as in the above embodiment, or the shaft insertion hole is used to elute and remove it. It is also possible.

Note that this invention is not limited to the embodiments described above, and it goes without saying that various modifications can be made without changing the gist of the invention.

[Effects of the Invention] As is clear from the above description, according to the present invention, a predetermined gap is provided around the cavity in the mold, and a core portion made of a low melting point alloy or the like with high pressure resistance can be eluted in advance. The components are inserted, positioned and fixed, and a raw material for molding the FRP outer shell with aramid fibers as reinforcing fibers is fed into the void from the hole penetrated toward the cavity in the mold to harden the head outer shell. After molding, while the core component is eluted to the outside, the core component is held and fixed to the tip of a feeding tube for raw material for FRP outer shell molding, and inserted into a mold and positioned and fixed. Therefore, it is possible to avoid the influence on the core component material due to the feeding pressure when feeding the raw material for FRP molding, and it is also possible to use aramid fiber cloth or aramid as reinforcing fibers for the raw material for FRP outer shell molding. Because a unidirectional bundle of fibers is used, the outer shell of the head has a lighter specific gravity and a slightly lower modulus of elasticity than carbon fiber-reinforced FRP, which prevents the head surface from becoming black. Not only can it improve aesthetics, but it also has an advantage against direct sunlight.
In addition, the present invention has been made possible by providing a manufacturing method for a golf club head that has excellent vibration damping characteristics, resulting in a softer hitting feel and improved quality. .

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of an embodiment of a golf club head manufactured by the method of manufacturing a golf club head according to the present invention, and FIGS. 2 to 6 are explanatory views showing the manufacturing process. 11...Core component material, lla...Outer peripheral surface, 13
...Feeding cylinder, 13a... Tip part, 14.1
5... Molding mold, 16... Cavity, 16a... Inner peripheral wall surface, 1
7...Mold hole, 18...Void, 20
... Raw material for FRP outer shell molding, 30... Head outer shell molded body.

Claims (6)

[Claims] (1) A first step of inserting, positioning and fixing a core component material that can be eluted in advance around a cavity in a mold with a predetermined gap, and inserting an FRP outer shell in which reinforcing fibers are made of aramid fibers into the gap. a second step of hardening and molding the head outer shell molded body by feeding raw material for molding into a cavity in the mold through a through-hole, and after hardening and molding the head outer shell molded body, the core A method for manufacturing a golf club head comprising a third step of eluting component materials to the outside. (2) A method for manufacturing a golf club head according to claim 1, characterized in that the core constituent material is eluted to the outside through a hole in the mold. (3) Scope of Claims In the method for manufacturing a golf club head according to claim 1 or 2, the core structure is formed in the head outer shell after the core component material is eluted. A manufacturing method characterized by covering the material elution hole with a plate-shaped weight member. (4) The method for manufacturing a golf club head as set forth in claim 3, characterized in that the plate-shaped weight member is embedded and fixed integrally at the same time as the head outer shell molding is hardened and formed. Manufacturing method. (5) In the method for manufacturing a golf club head according to either claim 3 or 4, the core component elution hole formed in the head outer shell molded body is covered. A manufacturing method characterized in that the plate-shaped weight member is a sole plate. (6) Scope of Claims In the method for manufacturing a golf club head as set forth in claim 1, a feeding tube having a core member fixed to a tip thereof directed from a hole penetrated through the mold toward the cavity. A manufacturing method characterized by: positioning the FRP shell in an inserted state, and feeding green material for forming an FRP shell using aramid fibers as reinforcing fibers into the gap around the cavity in the mold through the feeding tube.