JPH0445738Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a face insert for a golf club, and more specifically, a core made of wood or synthetic resin, commonly known as a driver, spoon, or batshui, is attached to the tip of a shaft. This invention relates to the structure of a face insert that is attached to the ball hitting surface of a golf club.

BACKGROUND OF THE INVENTION Golf clubs such as drivers, spoons, and golf clubs are used primarily to increase the flight distance of the ball. Golf clubs with cores made of wood or synthetic resin have face inserts molded from ABS resin, epoxy resin, etc. for the purpose of improving ball repulsion characteristics and protecting the ball hitting surface from deformation and damage due to impact. is attached to the ball hitting surface. When using a general-purpose thread-wound hole, the desired purpose can also be achieved with a golf club equipped with a face insert made of a molded synthetic resin material as described above, but the ability to increase flying distance is limited. With the spread of two-piece balls, which have high resistance, new problems have emerged.

Problems to be Solved by the Invention To explain in more detail, two-piece balls have higher hardness than thread-wound balls.
With face inserts molded from ABS resin, etc., it is difficult to maintain ball repulsion characteristics at a level that is practically satisfactory;
Hit marks and damage are likely to occur on the wooden part of the ball hitting surface and on the surface of the face insert due to collisions with hard balls.
In order to deal with this situation, for example,
-As disclosed in Publication No. 88634 or British Patent No. 1201648, a face insert made of carbon fibers or graphite fibers bonded with a matrix resin such as epoxy resin is installed instead of a conventional synthetic resin face insert. Golf clubs are commercially available. By using a synthetic resin face insert reinforced with carbon fiber, etc., the synergistic effect between the hardness of the ball and the material of the face insert creates the distance-improving function unique to two-piece balls and the ball-striking surface of a golf club. However, when manufacturing such face inserts, sufficient consideration is not necessarily given to the arrangement form and alignment direction of reinforcing threads formed from carbon fibers, etc. As a result, deformation may occur during resin impregnation due to insufficient bonding strength between fibers or reinforcing yarns, or between reinforcing yarns and matrix resin, and the alignment direction of reinforcing fibers may be distorted. Due to the mismatch between the impact load and the direction of action of the impact load, new problems have emerged, such as the repulsion characteristics and flexural modulus of the face insert not reaching the expected level.

Furthermore, by reducing the weight of the face insert reinforced with yarn, it is possible to increase the flight distance of the ball and improve the directional stability of the ball, but conventional face inserts have Regardless of whether the reinforcing fibers are arranged in a random orientation or in a cross-laminated manner, if the amount of reinforcing fibers is reduced below a certain permissible limit, the matrix resin mass or matrix resin is substantially free of reinforcing fibers. The disadvantage was that a layer was formed and the strength of the face insert was rapidly reduced.

The main purpose of the present invention is to create a golf golf ball that can solve the above-mentioned problems with conventional synthetic resin face inserts or synthetic resin face inserts with a matrix structure reinforced with yarns such as carbon fibers. Our goal is to provide face inserts for clubs.

Means for Solving the Problems In view of the above object, the present invention includes second reinforcing threads 2 meanderingly arranged in a zigzag pattern over the entire ball hitting surface of the face insert 10 in a direction perpendicular to the ball hitting surface S. , While enclosing a plurality of the second reinforcing threads 2 in a loop shape as a unit from one side edge to the other side edge along a plane parallel to the ball hitting surface S of the face insert 10. The yarn alignment surface 1' is formed by meandering in a zigzag pattern, and this meandering line is formed over the entire surface of the face insert 10 from one side edge to the other side edge to form the yarn alignment surface 1'. The first reinforcing thread 1 whose surface 1' is laminated in the thickness direction of the face insert 10, and the second reinforcing thread 2 exposed on the laminated surface of the first reinforcing thread 1 are placed at the folding point _T2 of the first reinforcing thread 1. A fiber structure 4 for reinforcing the face insert is constituted by a third reinforcing thread 3 inserted and arranged along the reinforcing thread lamination surface, and a golf ball is formed by impregnating and curing matrix resin 15 into the fiber structure 4. The gist is a face insert 10 for a club.

In order to achieve the above object, the characteristics of the constituent materials of the face insert 10 of the present invention are selected as follows. That is, the first to third reinforcing yarns 1, 2, and 3 constituting the fiber structure 4 are made of subcarbon fibers [low-temperature fired carbon fibers], carbon fibers, graphite fibers, aromatic polyamide fibers, and high-density polyethylene fibers. It is formed from a single type or multiple types of yarn selected from the group consisting of fibers and having a specific gravity of 0.95 to 1.80.

The first to third reinforcing yarns 1, 2, and 3 constituting the fiber structure 4 are mixed in a volume density of 10 to 50 percent.

The blending ratio of the matrix resin to the reinforcing yarns 1, 2, and 3 is adjusted so that the face insert after being impregnated and cured with the thermosetting resin or thermoplastic resin has a specific gravity of 0.90 to 1.50.

The matrix resin is selected from thermosetting resins or thermoplastic resins having a specific gravity of 0.92 to 1.30 selected from the group consisting of epoxy resins, urethane resins, ABS resins, and polyethylene resins.

Embodiment FIG. 1 is an enlarged perspective view of the face insert obtained in the first embodiment of the present invention, and FIG. 2 is an explanatory diagram of the aligned state of the carbon fiber threads in the first embodiment. be. Further, FIG. 3A is an enlarged perspective view of a face insert obtained in a second embodiment of the present invention, and FIG. 3B is a partially enlarged view thereof. Furthermore, FIG. 4 is an enlarged perspective view of the face insert obtained in the third embodiment of the present invention.

First, in the embodiment shown in FIGS. 1 and 2, the first to third carbon fiber threads 1, 2, and 3 are
"Trading card" made by firing acrylic fiber [registered trademark of carbon fiber manufactured by Toray Industries, Inc.] T300
3000 filament yarn [specific gravity 1.78] was used.
As seen in FIG. 2, the first carbon fiber yarn 1
is between the second carbon fiber threads 2 arranged in a meandering zigzag pattern from the first side edge 5 of the face insert 10 over the entire ball hitting surface in a direction perpendicular to the ball hitting surface S of the face insert 10. runs in the X-axis direction to reach the second side edge 6 of the face insert 10, and then changes the running direction at the side edge to loop the four second carbon fiber yarns 2. While encircling it, it meanders in a zigzag pattern and returns to the first side edge 5. The first carbon fiber yarn 1, whose running direction has been changed again at the first side edge, then meanders in a zigzag shape toward the second side edge 6, and is formed by the initial meandering. The four second carbon fiber yarns 2 are arranged in a surrounding manner between the loop 7 formed by the loop 7 and the loop 8 formed by the current meandering. In this way, the first
The carbon fiber yarn 1 changes its zigzag running path so that the alignment pitch with respect to the second carbon fiber yarn 2 is shifted by two lengths in the Y-axis direction, and thereafter the second carbon fiber yarn 1 is moved in the same manner. A zigzag-like movement is repeated between the first side edge 5 and the second side edge 6. This zigzag running of the first carbon fiber thread 1 forms a thread alignment surface 1' over the entire surface of the face insert 10 from the lower edge 17 to the upper edge 18 of the face insert 10. This yarn alignment surface 1' is repeated over a plurality of layers n by an amount corresponding to the thickness t of the face insert. On the other hand, the second carbon fiber yarn 2 is arranged in a zigzag shape that extends in the Z-axis direction through the alignment surface of the first carbon fiber yarn 1. A second thread alignment group is formed that is substantially perpendicular to the running directions X and Y of the thread 1, that is, perpendicular to the ball hitting surface S of the face insert 10. The direction of each fiber axis of the second carbon fiber yarn 2 is perpendicular to the ball-hitting surface S, that is, the line of action of compressive stress generated on the face insert 10 by a collision with a golf ball (not shown). By aligning the direction with the direction of , it functions as a member for improving the repulsion characteristics of the face insert 10 . Thus, the folding point of the second carbon fiber yarn 2 formed on the surface of the stack of the first carbon fiber yarn 1
T ₂ , that is, the loop 9 includes a second carbon fiber yarn 2
A third carbon fiber thread 3 that functions as a falling-off prevention member, that is, a cannula thread, is inserted.

The fiber structure 4 for reinforcing the face insert constructed in this manner is impregnated with a resin liquid 15 whose main component is a thermosetting matrix resin, for example, an epoxy resin [specific gravity 1.2], and then heated under predetermined temperature and pressure conditions. The face insert 10 is formed by curing with a hardener.

In the embodiments shown in FIGS. 3A and 3B, basically the same yarn arrangement form as in the embodiments shown in FIGS. 1 and 2 is adopted, but the face insert 10 Groove 1 formed on the ball hitting surface of
The laminated structure of the first carbon fiber thread 1 is devised so that the first to third carbon fiber threads 1, 2, and 3 are not cut by the carbon fiber thread 1. That is, in this embodiment, the loop of the first carbon fiber yarn 1 surrounding the second carbon fiber yarn 2 does not cross the groove 11 as shown in FIG. 3B.
By locating the loop of the carbon fiber yarn 1 inside the face insert 10, a strong face insert 10 is formed in which the cut end of the carbon fiber yarn is not exposed on the ball hitting surface.

On the other hand, in the embodiment shown in FIG.
The loop 9 of the second carbon fiber yarn 2 located on the ball hitting surface of the face insert 10 is looped by two first carbon fiber yarns 1 meandering along the X-axis direction and the Y-axis direction. A fiber structure 4 for reinforcing the face insert is formed by surrounding the carbon fiber in a closed loop and passing the third carbon fiber thread 3 as a cannulated thread through the loop 9.

The face insert shown in FIGS. 1 to 4 above has the fiber axis direction of any of the carbon fibers forming the fiber structure 4 aligned with the direction of the line of action of the impact load applied by the golf ball. They almost match. Therefore, according to the present invention, it is possible to simultaneously achieve an increase in flight distance due to the improvement in the repulsion characteristics of the face insert, and an improvement in durability due to the three-dimensional arrangement of carbon fibers. In the above embodiment, it is necessary that no cut ends exist at the folding points T ₁ and T ₂ of the carbon fibers 1 and 2 located on the surface of the face insert 10. In this way, by limiting the area where the cut end is formed and by utilizing the tightening force of the third carbon fiber that functions as a cannulated thread, it is possible to prevent the formation of cut ends during the impregnation process of thermosetting resin or thermoplastic resin or during transport between processes. It is possible to completely eliminate deformation of the fiber structure.

On the other hand, when hitting a ball with a golf club that has a heavy face insert fixed to the ball-hitting surface, a large weight is applied to the face surface, and the club face tends to become slightly overcast. For this reason, weak golfers are unable to raise the ball, resulting in decreased flight distance or dropped balls. Furthermore, if the weight of the face insert is large, the depth of the center of gravity of the persimmon head becomes shallow, resulting in poor directionality of the fly ball. In the present invention, the weight of the face insert 10 is made as light as possible in order to solve the above-mentioned problems, and as a means for achieving this purpose, the reinforcing threads 1, which constitute the fiber structure 4, 2,3 specific gravity
In the range of 0.95 to 1.80, and the blending ratio of reinforcing yarns constituting the fiber structure is expressed in volume density from 10 to 1.80.
Adjusted to 50% range. Further, by adjusting the specific gravity of the matrix resin 15 to a range of 0.92 to 1.30 and using this matrix resin together with the reinforcing yarn, the specific gravity of the face insert 10 is adjusted to a range of 0.90 to 1.50. When carrying out the present invention, as a means for reducing the weight of the face insert, as illustrated in FIGS. It can also be formed from a laminated structure consisting of strips.

Effects of the invention As can be understood from the above explanation, the face insert of the golf club according to the invention has high repulsion characteristics that match the hardness of the two-piece ball, is lightweight, and has durability, so it can improve flight distance. In addition to increasing the ball hitting direction and stabilizing the directionality of the ball, it is possible to reliably prevent dents and damage from occurring on the ball hitting surface of the face insert. Furthermore, since the cut ends of the threads that function as reinforcing threads are not exposed on the surface of the fiber structure that functions as a reinforcing member of the face insert, there is no deformation of the fiber structure during the molding process of the face insert. . Therefore, the present invention can exhibit remarkable effects in improving the quality and yield of face inserts.

[Brief explanation of the drawing]

FIG. 1 is an enlarged perspective view of the face insert obtained in the first embodiment of the present invention, and FIG. 2 is an explanatory diagram of the aligned state of the carbon fiber threads in the first embodiment. Further, FIG. 3A is an enlarged perspective view of a face insert obtained in a second embodiment of the present invention, and FIG. 3B is a partially enlarged view thereof. Furthermore, FIG. 4 is an enlarged perspective view of the face insert obtained in the third embodiment of the present invention. Moreover, FIGS. 5 to 8 are perspective views of face inserts formed of two or more types of reinforcing threads. 1...First reinforcing thread, 2...Second reinforcing thread, 3
... Third reinforcing yarn, T ₁ , T ₂ ... Turning point of yarn arrangement, 4 ... Fiber structure, 15 ... Thermosetting resin or thermoplastic resin, 10 ... Face insert.

Claims (1)

[Scope of Claim for Utility Model Registration] A second reinforcing thread arranged in a meandering zigzag pattern across the entire ball-hitting surface of the face insert in a direction perpendicular to the ball-hitting surface of the face insert, and a second reinforcing thread arranged in a zigzag pattern along a surface parallel to the ball-hitting surface of the face insert. , from one side edge to the other side edge,
A plurality of the second reinforcing threads are encircled in a loop shape and meandered in a zigzag pattern, and this meandering line is formed from one side edge to the other side edge over the entire surface of the face insert. a first reinforcing yarn laminated in the thickness direction of the face insert, and a folding point of a second reinforcing yarn exposed on the first reinforcing yarn lamination surface; and a third reinforcing thread inserted and arranged along the first reinforcing thread lamination surface to form a fiber structure for reinforcing the face insert, and formed by impregnating and curing the fiber structure with a matrix resin. A face insert for a golf club that is characterized by: