JP2008295940A - Manufacturing method of golf club shaft and golf club shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a golf club shaft capable of solving problems of deterioration of the shaft due to a phenomenon when being heated in a furnace that a prepreg laminated body moves toward a narrow-diameter side due to thermal shrinkage of a film, and defective products in a polishing step. <P>SOLUTION: Prepreg is wound around and laminated on a mandrel to expose at least one end of the mandrel 2 to provide a prepreg laminated body 100. Then, glass cloth prepreg is wound around to cover the prepreg laminated body and a part where the mandrel is exposed, to form a reinforced part 3. The obtained laminated prepreg is heated to provide the golf club shaft with the reinforced part 3 on the mandrel. The mandrel is pulled out from the golf club shaft 1, and the large diameter side end portion of the golf club shaft with the reinforced part is cut off leaving the reinforced part by 5-30 mm uncut on the large diameter side end portion of the golf club shaft, thus providing the golf club shaft. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a golf club shaft and a method for manufacturing the same.

In recent years, shafts made of FRP (Fiber Reinforced Plastics, fiber reinforced resin composite material) using carbon fibers as the main reinforcing fibers have been used as golf club shafts.
A shaft for a golf club made of FRP prepares a sheet-like prepreg obtained by impregnating a carbon fiber with a thermosetting resin such as an uncured epoxy resin, and the prepreg is wound around a rod-shaped mandrel and laminated. Next, after a heat-shrinkable film such as a polypropylene film is wound around the obtained prepreg laminate, it is heated by a heating furnace to cure the thermosetting resin, and then manufactured by a method of extracting a mandrel ( Patent Document 1).
Then, after cutting both ends, a molded product of a golf club shaft is obtained through a polishing process for polishing and smoothing the surface of the shaft. In the polishing process, physical properties of the shaft such as a natural frequency necessary for the golf club are adjusted.
Japanese Patent No. 2971374

  However, according to the conventional method, when using a tapered mandrel that gradually increases in diameter from the small-diameter side end to the large-diameter side end, and manufacturing a tapered shaft, when heated in a heating furnace, In some cases, the polypropylene film covering the heat shrinks, and thus the prepreg laminate also shrinks and moves to the small diameter side. Due to the furnace dropping, only a part of the carbon fibers flows, and the carbon fibers meander to deteriorate the quality of the shaft.

Further, in the polishing step of gradually polishing and smoothing the surface of the golf club shaft from one end to the other end, when polishing the large diameter side end of the golf club shaft, the contact area between the polishing machine and the large diameter side end is Since the pressure from the polishing machine is concentrated, the end portion of the golf club shaft tends to drop off, resulting in defective products.
An object of the present invention is to provide a golf club shaft manufacturing method capable of solving the problem of quality deterioration of a golf club shaft due to a furnace dropping phenomenon and defective products in a polishing process.
Another object of the present invention is to provide a golf club shaft having a reinforcing portion on the outer peripheral surface of the large-diameter side end portion of the tapered golf club shaft.

The manufacturing method of the shaft for golf clubs which reinforced the large diameter side end part of the present invention is characterized by performing the following (1)-(5) in order.
(1) A prepreg laminate is obtained by winding a prepreg obtained by impregnating a reinforcing fiber with a thermosetting resin around a mandrel so that the large-diameter side end of the mandrel is exposed, and laminating.
(2) A tape-shaped prepreg is wound around the end portion of the obtained prepreg laminate and the exposed mandrel to form a reinforcing portion.
(3) Heat to cure the thermosetting resin in the prepreg and the tape-shaped prepreg to obtain a golf club shaft with a reinforcing portion on the mandrel.
(4) Pulling out the mandrel from the golf club shaft with a reinforcing portion,
(5) The large-diameter side end of the golf club shaft with a reinforcing portion was cut to reinforce the large-diameter side end so that the reinforcing portion remains at 5-30 mm at the large-diameter side end of the golf club shaft. Get a golf club shaft

In the golf club shaft manufacturing method of the present invention, the width of the portion where the reinforcing portion formed by winding the tape-shaped prepreg overlaps with the prepreg laminate is 10 mm or more, and 10 mm on the exposed mandrel. It is preferable to wind as described above.
In the golf club shaft manufacturing method of the present invention, the reinforcing portion preferably has a thickness of 0.1 to 1 mm.
In the golf club shaft manufacturing method of the present invention, the tape-shaped prepreg preferably has a width of 20 to 60 mm.
In the golf club shaft manufacturing method of the present invention, the tape-shaped prepreg is preferably a glass cloth.
The golf club shaft of the present invention is characterized by having a reinforcing portion on the outer peripheral surface of the large-diameter end of the tapered golf club shaft.

According to the manufacturing method of the present invention, furnace dropping during heating can be prevented, quality deterioration due to this can be prevented, and the golf club shaft end portion is less likely to fall off in the polishing process, and the polishing process can be prevented. The problem of defective products can also be solved.
The shaft for golf clubs of the present invention has little quality deterioration and defective products.

  The present invention relates to a method for manufacturing a shaft for a golf club having a reinforced end portion, and an embodiment of the present invention will be described in detail below. The present invention is not limited to this embodiment.

In the production method of the present invention, as shown in FIG. 1, a prepreg obtained by impregnating a reinforcing fiber with a thermosetting resin is wound around a mandrel 2 so that the large-diameter side end of the mandrel 2 is exposed and laminated. Thus, the prepreg laminate 100 is obtained.
Thereafter, the tape-shaped prepreg is wound around the end portion of the obtained prepreg laminate 100 and the exposed mandrel 2 to form the reinforcing portion 3. At this time, the tape-shaped prepreg is wound around the end portion of the prepreg laminate 100 with a width a and the exposed mandrel 2 with a width b to form the reinforcing portion 3.
Thereafter, the film 10 having heat shrinkability is preferably wound around the prepreg laminate 100 and the reinforcing portion 3.
Next, it heats with a heating furnace, the thermosetting resin in the prepreg laminated body 100 and a tape-shaped prepreg is hardened, and the shaft for golf clubs with the reinforcement part 3 on the mandrel 2 is obtained.

  The film 10 is made of a heat-shrinkable synthetic resin, and the shape of the prepreg laminate 100 and the reinforcing portion 3 can be easily adjusted by winding the film 10 as shown in FIG. Further, since the film 10 has heat shrinkability, when the thermosetting resin is cured by heating, the film 10 can be simultaneously contracted, whereby the prepreg laminate 100 and the reinforcing portion 3 can be tightened. And a golf club shaft free of voids can be obtained. The film 10 is preferably a polypropylene film that is excellent in heat resistance and inexpensive.

In the conventional method, a furnace dropping phenomenon occurs by heating in a heating furnace. Due to the furnace dropping, only a part of the reinforcing fibers flowed and meandered, and the quality of the shaft was deteriorated.
However, in the present invention, the reinforcing portion 3 is applied to the prepreg laminate 100 and the mandrel 2, so that the prepreg laminate 100 and the mandrel 2 are firmly fixed. Therefore, even if the film is thermally contracted, the prepreg laminate is less likely to move to the small diameter side. Thereby, the furnace dropping phenomenon is hardly caused, and quality deterioration due to meandering of the reinforcing fibers can be prevented.

The width of the portion where the reinforcing portion 3 formed by winding the tape-shaped prepreg and the prepreg laminate 100 overlap is 10 mm or more (width a in FIG. 1), and 10 mm or more on the exposed mandrel 2 (FIG. 1) width b) It is preferable to wrap around.
After the molding, the width a (FIG. 1) of the reinforcing portion of the portion applied to the prepreg laminate 100 is 10 mm or more, so that the furnace falling phenomenon during heating can be made less likely to occur, and the reinforcing portion 3 can be used in the polishing process. It serves as a protective layer that protects the large-diameter end of the club shaft. Moreover, when the width b (FIG. 1) of the reinforcement part of the part concerning the mandrel 2 is 10 mm or more, the furnace dropping phenomenon at the time of heating can be made harder to occur.
The width of the tape-shaped prepreg is preferably 20 to 60 mm. As a result, the width of the reinforcing portion can be secured, it serves as a protective layer that protects the large-diameter side end of the golf club shaft in the polishing process, and the furnace falling phenomenon during heating can be made less likely to occur. .

  Moreover, it is preferable to wind a tape-shaped prepreg so that the thickness of the reinforcement part 3 is 0.1-1 mm. Thereby, it is possible to further prevent the furnace from dropping, and to increase the strength as the protective layer.

  The prepreg as the raw material of the shaft may be a prepreg in which reinforcing fibers are aligned in parallel, or a prepreg made into a sheet by impregnating a woven reinforcing fiber with a thermosetting resin. For example, a UD prepreg containing reinforcing fibers arranged in parallel, a woven prepreg containing woven reinforcing fibers, and the like can be used.

  Carbon fiber is preferred as the reinforcing fiber used in the prepreg, but in addition to carbon fiber, metal fiber, aramid fiber, silicon carbide fiber, alumina fiber, boron fiber can be used alone or in combination of two or more. You may use it in combination.

There is no particular limitation on the thermosetting resin impregnated in the reinforcing portion and the reinforcing fiber used for the golf club shaft, and examples thereof include an epoxy resin, an unsaturated polyester resin, an acrylic resin, and a phenol resin. In particular, an epoxy resin is preferable for obtaining a high-strength shaft.
Examples of epoxy resins include bifunctional epoxy resins: bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, fluorene type Examples thereof include epoxy resins and epoxy resins obtained by modifying them. Examples of the trifunctional or higher polyfunctional epoxy resin include phenol novolac type epoxy resin, cresol type epoxy resin, glycidylamine type epoxy resin such as tetraglycidyldiaminodiphenylmethane, triglycidylaminophenol, tetraglycidylamine, tetrakis (glycidyloxy) Examples thereof include glycidyl ether type epoxy resins such as phenyl) ethane and tris (glycidyloxymethane), epoxy resins obtained by modifying these resins, and brominated epoxy resins obtained by brominating these epoxy resins. Moreover, these epoxy resins may be used individually by 1 type, or may be used in combination of 2 or more type.
Furthermore, the thermosetting resin may be used in the form of a thermosetting resin composition containing various additives such as a curing agent, a release agent, a defoaming agent, an ultraviolet absorber, and a filler.
The tape-shaped prepreg used as the reinforcing portion 3 is preferably a glass cloth prepreg. Since the glass cloth prepreg is thin and highly versatile, it is preferably used as the reinforcing portion 3. The cross prepreg is a sheet formed by impregnating a woven reinforcing fiber with a thermosetting resin, has excellent strength, and is suitably used in the present invention.

Next, the mandrel 2 is pulled out from the golf club shaft with the mandrel 2 remaining in the hollow portion. The drawing may be performed by any method.
As shown in FIG. 1, the mandrel 2 is preferably provided with a reduced diameter portion 21 that hooks a member or the like for extraction at one end. Thereby, it becomes easy to perform extraction.

  Next, the large-diameter side end portion of the obtained golf club shaft is cut. When the large diameter side end is cut, the reinforcing part 3 is cut so that 5 to 30 mm remains at the large diameter side end of the golf club shaft. Thereby, as shown in FIG. 2, the golf club shaft 1 in which the reinforcing portion 3 remains at 5 to 30 mm at the end portion on the large diameter side can be obtained.

  Next, it is preferable to polish the surface of the golf club shaft 1. Thereby, it is possible to obtain a golf club shaft which is smoothed and has various physical properties necessary for the product.

The polishing is performed by a polishing machine having a polishing roll 4 and a rubber roll 5 with a polishing cloth attached to the outer peripheral surface as shown in FIG. The polishing machine only needs to have a cylindrical polishing roll 4 and a cylindrical rubber roll 5. The polishing roll 4 polishes the surface of the golf club shaft 1, and the rubber roll 5 rotates the golf club shaft 1. .
As shown in FIG. 2, the polishing roll 4 and the rubber roll 5 are rotated in the same direction around the central axes 41 and 51 in the length direction, and the rubber roll 5 causes the golf club shaft 1 to be long with the polishing roll 4 and the rubber roll 5. The wafer is rotated in the opposite direction around the central axis 11 in the vertical direction and moved in the length direction (arrow direction in FIG. 2) while being polished by applying a certain pressure with the polishing roll 4. Thereby, the surface of the golf club shaft 1 is gradually polished from the other end (small diameter side end) including the film 10 to one end (large diameter side end) having the reinforcing portion 3, and the entire golf club shaft 1 is polished. Polish and smooth.

In the polishing step of gradually polishing and smoothing the shaft surface from the small-diameter side end portion having no reinforcing portion 3 to the large-diameter side end portion having the reinforcing portion 3, the large-diameter side end portion of the golf club shaft 1 is When polishing, the contact area between the polishing cloth and the large-diameter side end of the polishing machine becomes small, so that pressure from the polishing machine is concentrated. Therefore, in the conventional golf club shaft 1 in which the end portion is not reinforced, the end portion is easily chipped or broken, and a defective product may occur.
However, in the present invention, the golf club shaft 1 has the reinforcing portion 3 at the end on the large diameter side. The reinforcing portion 3 serves as a protective layer for protecting the large-diameter side end portion of the golf club shaft 1 and can reinforce the shaft large-diameter side end portion. Therefore, chipping or cracking of the end portion on the large diameter side of the shaft due to polishing is less likely to occur. Thereby, defective products are less likely to occur.

  The golf club shaft manufactured according to the present invention has a reinforcing portion at one end thereof. The end portion is reinforced by the reinforcing portion, and even if the end portion is cut, the end portion is hardly raised. For example, a user may improve a golf club. At that time, the end of the shaft may be cut. In this way, when the end portion is cut, if the reinforcing portion is not provided, the cut surface of the end portion is easily raised. However, the reinforcing portion strengthens the end portion, and even if it is cut, it is difficult to raise.

  According to the method for manufacturing a golf club shaft of the present invention, the prepreg laminate and the mandrel are firmly fixed by the reinforcing portion, so that a furnace dropping phenomenon due to heat shrinkage of the film is less likely to occur, and quality deterioration due to meandering of reinforcing fibers Can be prevented. Further, since the golf club shaft has the reinforcing portion, the end portion is not easily chipped or cracked in the polishing process, and the problem of defective products in the polishing process can be solved.

It is sectional drawing which shows the structure of the shaft for golf clubs before hardening a thermosetting resin in this invention. It is sectional drawing which shows the outline of a grinding | polishing process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Golf club shaft 2 Mandrel 3 Reinforcement part 10 Film 100 Prepreg laminated body a Width of reinforcement part (portion overlapping prepreg laminated body)
b Width of reinforcement (portion on mandrel)

Claims (6)

The manufacturing method of the shaft for golf clubs which reinforced the large diameter side edge part which performs the following (1)-(5) in order.
(1) A prepreg laminate is obtained by winding a prepreg obtained by impregnating a reinforcing fiber with a thermosetting resin around a mandrel so that the large-diameter side end of the mandrel is exposed, and laminating.
(2) A tape-shaped prepreg is wound around the end portion of the obtained prepreg laminate and the exposed mandrel to form a reinforcing portion.
(3) Heat to cure the thermosetting resin in the prepreg and the tape-shaped prepreg to obtain a golf club shaft with a reinforcing portion on the mandrel.
(4) Pulling out the mandrel from the golf club shaft with a reinforcing portion,
(5) The large-diameter side end of the golf club shaft with a reinforcing portion was cut to reinforce the large-diameter side end so that the reinforcing portion remains at 5-30 mm at the large-diameter side end of the golf club shaft. Get a golf club shaft   The golf club according to claim 1, wherein the width of the portion where the reinforcing portion formed by winding the tape-shaped prepreg and the prepreg laminate overlap is 10 mm or more and the exposed mandrel is wound so as to take 10 mm or more. Manufacturing method for an automobile.   The golf club shaft manufacturing method according to claim 1 or 2, wherein the reinforcing portion has a thickness of 0.1 to 1 mm.   The method for manufacturing a shaft for a golf club according to any one of claims 1 to 3, wherein the tape-shaped prepreg has a width of 20 to 60 mm.   The method for producing a golf club shaft according to claim 1, wherein the tape-shaped prepreg is a glass cloth. A golf club shaft having a reinforcing portion on an outer peripheral surface of a large-diameter side end portion of a tapered golf club shaft.

Images