JP2729760B2 - Golf club iron head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an iron head for a golf club and, more particularly, to a structure for inserting a weight body mounted on an iron head by a lost wax method.

[0002]

2. Description of the Related Art Conventionally, in order to adjust the swing weight, balance and the like of an iron type golf club, a concave portion is provided on the back surface of an iron head, and the concave portion has a large specific gravity such as lead or tungsten carbide (WC). A method of fitting and fixing a body (weight) is well known. The weight body is usually fixed to the iron head using an adhesive or fixed with a hermetic plug screwed into the recess (for example, Japanese Patent Application Laid-Open Nos. 49-119731 and 50-108036). Gazette).

[0003]

However, the golf club receives a large impact load on the head each time the golf club hits the ball and generates vibrations. Therefore, the weight body fitted and fixed in the recess of the iron head as described above is There have been problems such as the adhesive being peeled off and falling off, the tight plug being loosened and the weight body rattling, and generating abnormal noise.

The present invention has been made in view of the above circumstances, and it is possible to fix the weight body to the iron head extremely firmly and securely by simply pressing the weight body into an insertion hole provided in the iron head. It is another object of the present invention to provide a structure for mounting a weight body in an iron head that can move the center of gravity of the head closer to the toe side and to a lower position.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a golf club having a weight body mounted on an iron head, wherein the golf club is provided with a bottom portion at an inner side of an insertion hole provided on a toe side of the head. An enlarged cavity portion that increases in diameter is provided, and a caulking protrusion is provided on the bottom portion, while the weight body has a cylindrical portion at least at a tip portion, and the weight body is pressed into the insertion hole. In this case, the cylindrical portion is expanded by the caulking protrusion and is caulked to the enlarged cavity.

The weight body has a specific gravity greater than that of the material of the iron head and is highly malleable.
A cylindrical body formed integrally with a shape having the cylindrical portion at the tip end portion thereof by using a copper alloy, lead, or the like; or a cylindrical body formed of an extensible metal material such as an aluminum alloy or brass; and a material of the iron head on the cylindrical body. Metal materials with higher specific gravity,
For example, a structure in which a sintered body such as pure tungsten or tungsten carbide is filled, and the cylindrical portion is formed by a tip portion of the cylindrical body. Further, it is preferable that a plurality of slits extending in an axial direction from an opening end are provided in the cylindrical portion.

[0007]

As described above, just by press-fitting the weight body into the insertion hole provided in the iron head, the cylindrical portion provided at the tip of the weight body is expanded by the caulking projection, and the enlarged cavity is formed. Because it is caulked to the part, the weight may fall off due to shock or vibration acting on the iron head,
There is no risk of loosening. Moreover, no additional fixing member such as an adhesive or a screw plug is required.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an iron head 1 of a golf club according to the present invention, which is precision cast by a lost wax method.
A hosel 4 for connecting a shaft (not shown) is integrally formed with a hitting portion comprising a face surface (hitting surface) 2 and a back surface 3 having a shape in which weight is appropriately distributed. A weight (weight) 10 for adjusting a swing weight and balance is mounted on the toe 5 side of the iron head 1 near the sole 6.

An insertion hole 7 for mounting the weight body 10 is provided from the end face of the toe 5 toward the inside, and as shown in FIG. An enlarged cavity 8 for expanding the diameter and a protruding portion 9 for caulking are provided, and an inner wall surface 8a of the enlarged cavity 8 is formed into a smooth trumpet-like curved surface, and an outer surface 9a of the protruding portion 9 for caulking. Are also formed on a smooth curved surface.

The weight insertion hole 7 having such a shape
Can be formed simultaneously with the casting of the iron head 1. That is, as shown in FIG. 5, when a wax mold 21 for manufacturing the iron head 1 by a lost wax method is injection-molded, a water-soluble urea having a round bar 23 provided with a trough-shaped enlarged concave portion 24 is provided at the tip. Resin core 2
The iron head 1 is cast only by inserting and fixing the core 2 into the wax mold 21 so as to be positioned closer to the sole 6 from the end face on the toe 5 side, and after the wax mold 21 is completed, the core 22 is melted and removed with water. At the same time, the insertion hole 7 having the enlarged cavity 8 and the caulking protrusion 9 is precisely formed. In the figure, 25
Is a part to be a gate at the time of casting.

As shown in FIG. 6, a weight body 10 is made of a cylindrical body 11 formed of a highly malleable metal material such as an aluminum alloy or brass, and a specific gravity of a material (for example, soft iron or stainless steel) of the iron head 1. And a sintered body 12 formed of a metal material such as lead, pure tungsten or tungsten carbide (WC) having a large diameter. The cylindrical body 11 is formed in a bottomed cylindrical body having a bottom portion 13 at a rear end, and the cylindrical body 11 is filled with a sintered body 12 and is supported on the bottom portion 13 in a state where the sintered body 12 is in contact with and supported by the bottom portion 13. A plurality of slits 14 extending in the axial direction are formed on the inner wall surface of the cylindrical portion 11a by forging, and the sintered body 12 is fixed to the cylindrical body 11 with the extra thickness 15 so that the cylindrical portion 11a remains. Further, by providing the slit 14 in the cylindrical portion 11a, the caulking deformation of the cylindrical portion 11a described later is facilitated. Reference numeral 16 denotes a confirmation hole provided in the bottom 13.

The weight body 10 does not necessarily need to be composed of two members, a cylindrical body 11 and a sintered body 12, as shown in the figure. A metal material having a higher specific gravity than the material of the iron head 1 and rich in malleability is used. For example, it may be manufactured as a single member having a cylindrical portion at a tip end portion using copper, a copper alloy, lead, or the like.

As shown in FIG. 3, the weight body 10 constructed as described above is inserted into the insertion hole 7 of the iron head 1 from the cylindrical portion 11a at the tip, and is fixed to the iron head 1 by tapping with a hammer or the like. . That is, the weight 10
Is press-fitted into the insertion hole 7, as shown in FIG. 4, the cylindrical portion 11 a is expanded by the caulking projection 9 and is caulked to the enlarged cavity 8. At this time, since the inner wall surface 8a of the enlarged cavity 8 and the outer surface 9a of the protruding portion 9 are formed into a smooth curved surface, the cylindrical portion 11a easily expands and enters the corner of the enlarged cavity 8. And is firmly fixed. Further, as shown in FIG. 6, a slit 14 is formed in the cylindrical portion 11a.
Is provided, the cylindrical portion 11a is broken at the position where the slit 14 is provided, and can be more easily and surely expanded. Then, as shown in FIG. 4, the weight body 10 is press-fitted to a position where the sintered body 12 abuts on the caulking protrusion 9, and is fixed to the iron head 1, and after the cylindrical body 11 protrudes from the insertion hole 7, Finish by removing the end protruding part by polishing.

FIG. 7 shows another embodiment of the weight body 10. The cylindrical body 11 has a cylindrical part 11a at the tip and a sintered body 1
2 and a partition 17 for partitioning the rear cylindrical portion 11b into which the sintered body 12 is filled. As described later, the filled sintered body 12 is fixed to the inner wall surface of the rear cylindrical portion 11b so as to eliminate the backlash. An annular protruding edge 18 and an annular recess 19 for forming an annular ridge on the outer periphery of the rear cylindrical portion 11b are provided.

When the weight body 10 configured as described above is inserted into the insertion hole 7 of the iron head 1 and press-fitted, first, a first punch (not shown) having a diameter slightly smaller than the inner diameter of the rear cylindrical portion 11b is used. The sintered body 12 is fixed to the rear cylindrical portion 11b by caulking the annular protruding edge 18, and the tip cylindrical portion 11a is expanded by the caulking protruding portion 9 and caulked to the enlarged cavity 8 as described above. At this time, the weight body 10 is press-fitted to a position where the partition wall 17 comes into contact with the caulking projection 9. Subsequently, the rear cylindrical portion 11 is pressed by a second punch (not shown).
When the rear end of the b is knocked in, as shown in FIG. 8, the portion where the annular concave portion 19 is provided is bent to form an annular raised portion 19 a on the outer periphery, so that the annular raised portion 19 a is inserted into the insertion hole 7. The cylindrical body 11 is securely fixed to the insertion hole 7 by engaging with the annular concave portion 7a provided in
It is possible to eliminate movement with zero play.

FIGS. 9 and 10 show an example in which a weight body 10 is mounted on the back surface 3 of a cavity-back type iron head 1. FIG. In this embodiment, the insertion hole 7 is provided across the cavity 31 from the sole 6 near the toe 5, and an intermediate portion of the weight body 10 inserted into the insertion hole 7 is exposed in the cavity 31. I have. With such a structure, it is possible to give specificity to the design.

[0018]

As described above, according to the present invention,
By simply press-fitting the weight body into the insertion hole provided in the iron head, the weight body can be firmly and surely fixed to the iron head by the caulking structure, and there is no possibility that the weight body is loosened or dropped by a strong impact force or vibration. In addition, since no fixing member such as an adhesive or a screw stopper is required as in the conventional case, the number of parts is small and workability is excellent.

When assembling an iron set for a golf club, it is necessary to change the head weight variously depending on the shaft specifications. That is, since there is a large difference in weight between the black shaft and the steel shaft, it has conventionally taken considerable effort to control the weight of the head. However, according to the present invention, the head weight can be easily changed by changing the specification of the weight body, and the weight management of the head becomes easy.
Furthermore, since the insertion hole of the weight body is provided inward from the toe or sole near the toe side, the center of gravity of the head is further closer to the toe side by the weight body press-fitted into the insertion hole, and low. It is possible to move to the position, and the degree of freedom in designing the iron head is greatly improved. Also,
The moment of inertia of the head can be made larger than conventional products.

[Brief description of the drawings]

FIG. 1 is a front view of an iron head according to the present invention.

FIG. 2 is a side view of the iron head according to the present invention as viewed from the toe side.

FIG. 3 is an enlarged cross-sectional view of a main part of an iron head, showing an inserted state before a press-fitting of a weight body.

FIG. 4 is an enlarged cross-sectional view of a main part of the iron head showing a state where the press-fitting of the weight body is completed.

FIG. 5 is an enlarged sectional view of a main part showing a wax mold for manufacturing the iron head by a lost wax manufacturing method.

FIG. 6A is a longitudinal sectional front view of a weight body, and FIG. 6B is an end view of the weight body.

FIG. 7 is a vertical sectional front view showing another embodiment of the weight body.

8 is an enlarged cross-sectional view showing a state where the press-fitting of a main part of the iron head using the weight body of FIG. 7 is completed.

FIG. 9 is a perspective view showing another embodiment of the iron head according to the present invention.

FIG. 10 is a sectional view taken along the line 10-10 in FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Iron head 2 Face surface 3 Back surface 5 Toe 6 Sole 7 Insertion hole 8 Enlarged cavity 8a Inner wall surface 9 Protrusion for caulking 9a Outer side surface 10 Weight body 11 Cylindrical body 11a Cylindrical part 12 Sintered body

Claims (5)

(57) [Claims] 1. A golf club in which a weight body is mounted on an iron head, wherein an enlarged cavity portion expanding in diameter toward a bottom is provided inside an insertion hole of the weight body provided on a toe side of the head. A crimping protrusion is provided on the bottom portion, while the weight body has a cylindrical portion at least at a distal end portion, and the cylindrical portion is press-fitted into the insertion hole, whereby the cylindrical portion is crimped. An iron head for a golf club, wherein the iron head is expanded by being crimped and connected to the enlarged cavity by caulking. 2. An inner wall surface of the enlarged cavity portion is formed as a horn-like smooth curved surface whose diameter gradually increases toward a bottom portion, and an outer surface of the caulking protrusion is also formed as a smooth curved surface. The golf club iron head according to claim 1, wherein the iron head is formed. 3. The weight body is composed of a cylindrical body formed of a highly malleable metal material, and a sintered body of a metal material having a higher specific gravity than the material of the iron head filled in the cylindrical body, and 3. The iron head for a golf club according to claim 1, wherein the cylindrical portion is formed by a tip portion of the cylindrical body. 4. The cylindrical body has a bottom portion at a rear end, and a plurality of slits extending in an axial direction are formed on an inner wall surface of the distal end cylindrical portion by axial forming, and the cylindrical body is filled with extra thickness. 4. The iron head for a golf club according to claim 3, wherein said iron head is configured to fix said sintered body. 5. The cylindrical body has a partition wall for partitioning the cylindrical portion at a tip portion and a rear cylindrical portion filled with the sintered body, and the inner wall surface of the rear cylindrical portion has the partition wall. 4. The iron head for a golf club according to claim 3, wherein an annular ridge for fixing the sintered body and an annular recess for forming an annular ridge are provided.