JPH084642B2 - Golf club head manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a golf club such as a metal wood having a metal head.

[0002]

2. Description of the Related Art A head of a so-called metal wood golf club is manufactured by a precision casting method using a stainless alloy, an aluminum alloy, a titanium alloy or a beryllium-copper alloy as a raw material. However, since this precision casting head is a cast product, segregation of components and casting defects are present, and the crystal grains are coarse, 0.5 mm or more. Therefore, the conventional precision casting head has a drawback that mechanical properties such as proof stress and tensile strength are low. Since the mechanical properties are low as described above, it is difficult to reduce the wall thickness, and it is not possible to increase the size of the head while avoiding an increase in weight. For this reason, since the conventional metal wood has a small head volume, it has a drawback that the sweet area is small and the directional stability of the hit ball is low.

Therefore, recently, a head has been proposed in which head parts are manufactured by a plastic working method such as forging or pressing, and these parts are assembled by welding to make a product.

FIG. 12 is a sectional view showing a conventional method of assembling a head of this type, and FIG. 13A is a sectional view showing the head after this assembly. As shown in FIG. 12, the face portion 1 of the head and the head main body portion 2 that supports this face portion are separately produced, and as shown in FIG. 2 is welded and fixed to the peripheral portion (welded portion 3) of the face portion 1 to manufacture a head having a cavity. The main body portion 2 is further divided into upper and lower parts, and after the main body portion 2 is assembled by joining the respective portions, the face portion 1 is joined and fixed to the main body portion 2.

FIGS. 14A to 14C are schematic views showing a conventional method of manufacturing a head. First, as shown in FIG. 14A, the face portion 1, the crown portion 2a, and the sole portion 2b are separately produced. Therefore, when the head model mold is manufactured, the parting line of this model is determined so that the reverse gradient does not occur, and it has the same shape as the crown portion 2a and the sole portion 2c shown in FIG. 14 (a). Create a split model. Then, as shown in FIG. 15, a molding die 5 is produced using this divided model. Next, a Ti alloy plate 6 is sandwiched in the mold 5, and the Ti alloy plate 6 is heated to 950 ° C., while Ar gas is introduced into the mold 5 from the side opposite to the molding surface of the mold 5 at a pressure of 3 MPa. Then, the Ti alloy plate 6 is pressed against the molding surface of the mold 5. By continuing this for 60 minutes, the Ti alloy plate is deformed along the molding surface of the mold 5 and molded into a predetermined shape shown in FIG. Next, each part is taken out from the mold 5, and unnecessary parts are cut and removed. The face part 1
Is a plate that is cut.

Next, among these parts, FIG.
As shown in (b), first, the crown portion 2a and the sole portion 2 are
14b, and then the face portion 1 is welded to the front end face of the main body portion 2 at its peripheral portion, as shown in FIG. 14 (c). As a result, the head is completed, and a forzel (not shown) separately produced by cutting is welded and fixed to the head to complete the golf club.

[0007]

However, the conventional head in which the parts manufactured by this plastic working are assembled by welding has the following drawbacks. That is, FIG.
As shown in (b), when the ball 4 is hit, the face portion 1 is curved in an arc shape in a sectional view. Then, when the ball is hit, compressive stress acts on the welded portion 3 and bending stress also acts due to the arcuate deformation of the face portion 1. In the welded portion 3, the end surface of the head main body portion 2 is joined to the back surface of the face portion 1, but there is a drawback that the welded portion 3 is easily damaged by the action of this bending stress. Therefore, the conventional head has a difficulty in durability of the welded portion 3 at the peripheral portion of the face portion 1.

Further, in the conventional head, since the face portion 1 and the main body portion 2 are manufactured by plastic working, respectively, and the both are simply welded and fixed, the dimensional accuracy during assembly is low and the productivity is low. There is.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a method of manufacturing a golf club head which has excellent durability and high dimensional accuracy and productivity.

[0010]

A method for manufacturing a golf club head according to the present invention is a method for manufacturing a golf club head in which a face portion and an extending portion extending from the face portion toward the rear of the head are integrally formed. In the above, the step of producing a plurality of parts consisting of the integrally formed portion and the other portion divided into one or two or more by plastic working, the step of producing the head core portion by wax, and the step of It is characterized by including a step of joining the respective parts together and a step of melting and discharging the wax.

[0011]

[0012]

Further, instead of using the wax core portion, or in addition to this core portion, a fitting protrusion is provided at the joint between the integrally molded portion and the other portion, and the protrusion is used. You may position each part.

[0014]

In the method of the present invention, a plurality of parts including the integrally formed part and the other part are positioned by positioning a wax core part therein, and then these parts are joined together, Next, for example, the head wax is manufactured by heating the wax of the core portion and discharging it from the forzel portion or the like. Therefore, the positioning of each part is easy, the productivity is improved, and the accuracy of the head shape is high. This effect is the same when the fitting protrusion is provided at the joint.

[0015]

[0016]

Embodiments of the present invention will be specifically described below with reference to the accompanying drawings. FIG. 1 is a sectional view showing a golf club head according to an embodiment of the present invention. The golf club head 10 of this embodiment includes a portion 1 including a face portion 11.
0a and the other main body portion 10b. The portion 10a includes a face portion 11 and the face portion 1
1 and an extension portion 14 extending rearward of the head 10,
The face portion 11 and the extension portion 14 are integrally formed by plastic working. The extending portion 14 constitutes part of the sole and crown of the head. On the other hand, the body portion 10b
Is formed of a divided body of two or three or more divisions as described later, or an integrally formed body, and the front end surface of the main body portion 10b and the rear end surface of the extending portion 14 are joined by welding. The welded portion 13 is provided.

In the golf club head thus constructed, as shown in FIG. 2, when the ball 4 is hit,
Due to the reaction force received from the ball 4, the face portion 11 is curved in a bow shape in a sectional view. In addition to the compressive stress, bending stress is also applied to the boundary between the face portion 11 and the extending portion 14. However, since the face portion 11 and the extending portion 14 are integrally molded at this boundary portion, the bending stress does not cause damage. On the other hand, the portion 10a and the main body portion 10b are fixed by the welded portion 13, but since only the compressive stress acts on the welded portion 13 at the time of hitting the ball and the bending stress does not act on the welded portion 13, damage may occur at this portion. There is no.

Next, a method of manufacturing the head having the above structure will be described with reference to FIGS. First,
As shown in FIG. 3, a portion 10 a including a face portion 11 and an extending portion 14, a crown portion 12 a, and a sole portion 12
Create b and. In this case, in addition to the crown portion 12a and the sole portion 12b, the portion 10a is also formed by superplastic working using a mold as shown in FIG.

Next, the head core model 15 shown in FIG.
Is made with wax. The core model 15 conforms to the internal shape of the head and is made of wax so that it can be fluidized and discharged by heating.

Thereafter, as shown in FIG. 5, the core model 1
5, the crown portion 12a, the sole portion 12b,
By assembling the part 10a, each part (crown part 12a,
The sole part 12b and the part 10a) are welded and fixed to each other.

Next, the head core model 15 is heated to a temperature equal to or higher than its melting temperature to fluidize the model 15 and let it flow out from the Forzel part. As a result, a head having a cavity inside is completed. Then, this head is welded and fixed to the forzel portion.

As a result, the golf club head shown in FIGS. 1 and 2 is manufactured. In the method of this embodiment, since the head core model 15 that is heated and melted and then discharged is used, and the parts are arranged in accordance with the core model 15, the positioning accuracy of these parts is high, and therefore welding is performed. The head obtained later has a high precision and conforms to a predetermined shape. Further, since the positioning of each part is easy, the productivity is also improved.

Next, another embodiment of the present invention will be described with reference to FIGS. Also in this embodiment, similar to the previous embodiment, the portion 20a having the face portion 21 and the extending portion 24, the crown portion 22a, and the sole portion 22b.
All parts consisting of and are manufactured by superplastic working.
However, in this embodiment, the projections 26a are respectively formed on the end surfaces of the crown portion 22a and the sole portion 22b on the portion 20a side.
And 26b are provided. These protrusions 26a, 26b
As shown in FIGS. 7 and 8, when the crown portion 22a and the sole portion 22b are overlapped with each other, the end surface of the portion 20a that is connected in an annular shape and is composed of the face portion 21 and the extension portion 24 is formed. Has a shape that is fitted to.

In the present embodiment, each part including the portion 20a is manufactured by superplastic working using a mold as shown in FIG. Then, as shown in FIG. 7, first, the crown portion 22a and the sole portion 22b are welded and fixed. Thereafter, as shown in FIG.
The portion 20a is fitted to 6b, and the two are fixed by welding at this fitting portion. Next, the forzel portion is welded.

In the present embodiment, the wax model 15 is not used, but since the parts are positioned by using the fitting protrusions 26a and 26b, the positioning is easy as in the previous embodiment. Therefore, a highly accurate head can be manufactured and the productivity is high. Further, since the welding area is wide by the amount of this protrusion, this embodiment has an advantage that the strength of the welded portion is increased. Incidentally, it goes without saying that a wax model may be used in the present embodiment.

In the present embodiment, after the parts shown in FIG. 6 are manufactured, these parts may be directly assembled as shown in FIG. 8 and then the parts may be welded and fixed to each other.

The mold for producing each part may be manufactured as follows. As shown in FIG. 9, a resin model 30 that matches the outer shape of the head is manufactured, and this resin model 30 is cut at a position (cutting line 31) corresponding to the end face of the extending portion 24. A parting line 32 is provided at a position slightly rearward of the cutting line 31, and a region 33 between the parting line 32 and the cutting line 31 is provided.
The surface is cut and removed to an appropriate depth. After that, the model on the side from which the surface is removed is cut up and down along a cutting line 34 as shown in FIG. Then, a die may be produced based on these three models.

Next, the protrusion 2 of the head shown in FIGS.
The results of testing the relationship between the shapes of 6a and 26b and the durability of the head will be described. As shown in FIG.
The thickness of the extending portion 24 following the face portion 21 is x, and the protrusion 26 is
The length of a and 26b is y. These values x and y in each production example are shown in Table 1 below.

[0029]

[Table 1]

Then, the heads of the respective production examples were subjected to a 10,000 ball hit test, and as a result, none of the heads was damaged.

Further, with respect to the head of each manufacturing example, the surface deviation between the crown portion 22a or the sole portion 22b and the extending portion 24 was examined. 100 models of each manufacturing example were produced, and the average value (mm) of the deviation amount was calculated. The results are shown in Table 2 below. As shown in Table 2, the displacement amount of each head was very small.

[0032]

[Table 2]

[0033]

As described above, according to the present invention,
Since the face portion and the extended portion extending to the rear of the head are integrally formed, and the end portion of the extended portion and the head main body portion are joined together, the stress applied at the time of hitting the face portion and the extended portion Even if a bending stress is applied to the boundary, no damage occurs in this part. Further, since only the compressive stress acts on the joint portion and the bending stress does not act on the joint portion, damage does not occur even in this portion.

Further, according to the method of the present invention, since the wax model is used or the projections are provided, the positioning of each part is easy, and a highly accurate head can be manufactured, and its productivity is high.

[Brief description of drawings]

FIG. 1 is a sectional view showing a head according to an embodiment of the present invention.

FIG. 2 is a sectional view showing an operation of hitting a ball.

FIG. 3 is a schematic view showing parts used in the method according to the embodiment of the present invention.

FIG. 4 is a diagram showing a head core model of the same.

FIG. 5 is a cross-sectional view showing the same assembled parts.

FIG. 6 is a schematic view showing parts used in a method according to another embodiment of the present invention.

FIG. 7 is a schematic view showing the assembling process of the same.

FIG. 8 is a schematic view showing the assembling process of the same.

FIG. 9 is a schematic view showing a resin model for producing the same mold.

FIG. 10 is a schematic diagram showing the mold production resin model.

FIG. 11 is a schematic view showing the shape of the protrusion.

FIG. 12 is a sectional view showing parts of a conventional head.

FIG. 13 is a cross-sectional view showing a conventional head.

FIG. 14 is a schematic view showing a conventional head manufacturing method.

FIG. 15 is a cross-sectional view showing a mold used for plastic working.

[Explanation of symbols]

1, 11, 21; Face part, 2; Main body part, 3, 1
3: Welded part, 12a, 22b; Crown part, 12a, 1
2b; sole portion, 14, 24; extension portion, 15; core portion model, 26a, 26b; protrusion

Claims (3)

[Claims] 1. A method of manufacturing a golf club head in which a face portion and an extending portion extending from the face portion toward the rear of the head are integrally formed, the method including the step of dividing the integrally formed portion into one or two or more parts. The step of producing a plurality of parts by plastic working, the step of producing the head core part with wax, the step of joining the parts to each other according to the head core part, and the wax And a step of melting and discharging the golf club head. 2. The method according to claim 1, further comprising the step of providing a protrusion for fitting one of the integrally formed portion and the other portion to the other at least one of the joined portions. Manufacturing method of golf club head. 3. A method for manufacturing a golf club head in which a face portion and an extending portion extending from the face portion toward the rear of the head are integrally formed, the method including the step of dividing the integrally formed portion into one or two or more parts. And a step of forming a fitting protrusion on at least one of the joints between the integrally formed portion and another portion, and using the fitting protrusion. And a step of assembling the above-mentioned respective parts and joining them to each other.