MXPA96003945A

MXPA96003945A - Formation of metal head for palo de g

Info

Publication number: MXPA96003945A
Application number: MXPA/A/1996/003945A
Authority: MX
Inventors: H Schmidt Glenn
Original assignee: Callaway Golf Company
Filing date: 1996-09-06
Publication date: 1998-10-15

Abstract

In the method for forming a metallic and hollow golf club head having a wall structure defining a front wall, a heel, a tip, a rear wall, a base and an upper wall, the steps include providing a body covered by a wax coating, the thickness of the wax coating corresponding to the desired thickness of the wall structure, forming a ceramic coating around said wax coating, removing the wax coating by melting the wax, to form in this way an opening between the ceramic liner and the nuclear body and melt melted metal inside the opening, to thereby form the wall structure that extends around the nuclear body and at the base, while a structure is formed and maintained of entrance through the wall structure and separated from the base, and allow the wall structure to solidify to form the head; ceramic structure of the wall structure and remove the nuclear body from the inside of the solidified head and through the structure of the

Description

METAL FORMING FOR PALO DE GOLF BACKGROUND OF THE INVENTION This invention relates generally to the formation of metallic, hollow golf club heads and more particularly to the use of a nuclear body in such a way in a lost wax process to eliminate the need to form a large opening in the region of the base of the molten metal head.

At present, metal heads for golf clubs are usually formed by casting metal around a nuclear body and in such a way that a large opening is formed in the region of the base of the head. A separate base platform is subsequently attached to the head to cover that opening. The soldier spreads in a large circle and is the source of problems that include undesirable differences in weight between the heads during their manufacture; variations of soldier around the circle; possible rupture of the soldier during the charge of the blow on the impact at high speed of the head with a golf ball; and difficulties encountered during the welding process due to very thin walls that are connected to the weld. There is a need for a method and means to eliminate such problems.

SUMMARY OF THE INVENTION It is a principal object of the present invention to provide an apparatus and methods for manufacturing heads that solve said problems. Basically, the method of the invention includes the steps: a) providing a nuclear body formed as a club head, preformed and covered with a wax coating, the wax coating covering the base area of the nuclear body, the thickness of the wax coating corresponding to the desired thickness of the structure the walls of the head, b) forming a ceramic coating around the wax coating, c) removing the wax coating by melting the wax, to thereby form an opening between the ceramic coating and the nuclear body, d) and melt molten metal within the aperture, to thereby form the wall structure that extends around the nuclear body including the core area of the nuclear body, while the structure of entrance through the structure of the core is formed and maintained. wall and distanced from the base and allowing the wall structure to solidify to form the head, e) remove the ceramic lining from the wall structure and rowing see the nuclear body inside the head solidified by the input structure.

As it will appear, the nuclear body is preformed and can normally consist of molded ceramic material.

Another object of the invention is to provide the entrance structure for extending through the rear wall of the wall; and that the input structure is normally formed to have a total size substantially less than the total size of the base. Multiple small access doors can be formed through the back wall of the wall, where the tension that arises during the impact of the head with the ball of golf is substantially smaller than in other regions of the structure of the walls of the head. These small entries can be closed by welding small plugs to the head.

Still another objective includes fused formations of a metal base defining an edge and two concave recesses on opposite sides of said edge, the multiple access ports formed backwardly of said concave recesses.

A further objective includes providing the nuclear body to define an elongated recess slot in the surface of the nuclear body and corresponding to an elongated support rib by being formed in the structure of the head wall on the inner side thereof. The multiple access ports formed through the rear wall of the head are normally located on opposite sides of a plane defined by the support rib.

Another objective includes providing multiple holders of the position of the nuclear body to extend between the opening between the nuclear body and the ceramic liner. Said holders are normally provided during the formation of the ceramic coating around the wax coating.

Another objective includes providing the nuclear body covered by the wax coating with: i) providing a preformed nuclear body as referred to and having the general shape of the head, ii) placing said body within a cavity formed by the structure of the mold, thus providing an initial opening around the nuclear body, iii) and filling with wax within the initial opening to cover the nuclear body and to form the wax coating.

These and other objects of the invention as well as the details of an exemplary and demonstrative method will be more fully understood from the following description and drawings, in which: DESCRIPTION OF THE DUCTS Figure 1 is a flow diagram; Figure 2 is a perspective view of a golf club head; Figure 3 is a section taken on lines 3-3 of Figure 2; Figures 4, 5 and 6 are enlarged sections taken on lines 4-4, 5-5 and 6-6 of Figure 3; Figure 7 is a posterior elevational view taken on lines 7-7 of the Figure 3; Figure 8 is a vertical section taken through a mold showing the formation of a wax coating around a preformed nuclear body; Figure 8a is a section taken on lines 8a-8a of Figure 8; Figure 9 is a view similar to Figure 8, showing the nuclear body covered in the wax coating after removing it from the mold; Figure 10 is a view similar to Figure 8, but showing the formation of a ceramic coating around the nuclear body covered by the wax coating; Figure 11 is a view similar to Figure 10, showing the ceramic coating extending around the preformed core, after the wax has been removed to form an opening to receive the melted metal that forms the head of the golf club; Y Figure 12 is a planar view of the bottom of a hollow metal head, with ports in the rear wall.

DETAILED DESCRIPTION In reference first to Figure 1, the illustrated flow chart basically includes the steps (a) - (e), wherein step (a) may for example be carried out by carrying out the preliminary steps 1) - iii).

Step a) designates the proportion of a preformed nuclear body covered with a wax coating. See the preformed nuclear body 10 and the wax covering 11. The body 10 is schematically illustrated in the shape of a golf club head. The body 10 is usually formed of a ceramic material, such as for example ceramic particles bonded with synthetic resins, in a known manner, to form a solid mass, which is brittle.

Step b) consists of the formation of a wax coating 12 around the wax coating, with multiple introductions within the ceramic slurry and then allowing it to harden, around the wax, in successive layers.

Step c) consists in removing the wax coating by melting the wax, to thereby form an open opening 13 between the ceramic coating 12 and the nuclear body.

Step d) consists of melting molten metal 14 within open aperture 13 to thereby form the wall structure of the product, allowing to dry in situ. In the case of the hollow metal golf club head as seen in Figures 2 and 3, said wall structure includes an anterior wall 20, a heel 21, a tip 22, a curved rear wall 23, a base 24 and an upper wall 25. Note that the wall of the integral base 24, continuous together with 20 and 23, is formed by this step, that is, no large opening is left open in the base position, so one step Additional welding of a large base platform to a large circular hoop provided by the wall structure around the base is eliminated and the problems associated with such welding are eliminated.

A relatively small input structure (a single entry or other multiple ports) is formed and maintained in the position located remotely from the base 24. See for example the port 16 formed through the downward curved rear wall 23 of the Wall structure, such curvature in the rear wall provides strength to the wall at the relatively small port site 16, so weakness to the detriment of the structure of the wall is avoided. In the case of a golf club head, port 16 is usually less than Vi square inch in the cross-sectional area. Also, its vertical height "h" becomes substantially less than its horizontal length "1", to minimize any weakness of the wall structure. See Figure 7. The rear wall 23, in which the ports 16 are formed, is bidirectionally curved, ie, in the vertical plane (the plane of Figure 3) and the horizontal plane 17, in position directed to the ball of head.

Step e) consists in removing the fragile ceramic lining 12, breaking it, from the solidified wall metal structure, in the form of a metallic liner illustrated as 30 and also removing the nuclear body 10 from inside the metallic lining, through of port 16 or ports, formed in the rear wall 23. In this regard, a tool can be passed through port 16 and inside the metal sheath 30, to break the ceramic core 10 (or other material) in small pieces, removed through port 16.

The preliminary steps to reach the curved nuclear body covered in wax provided are shown in Figure 1 in i), ii) and iii). Step i) consists in providing the preformed nuclear body 10 alone. Such techniques are well known and may include Sintering a mass of ceramic particles held in shape by a resin glue. Step ii) consists of placing the body 10 within a cavity 33 formed by the structure of the mold 34, to provide an initial opening 35 between the body 10 and the wall of the cavity. Opening 35 corresponds to opening 13, cited above. The small holders or spacers 16 are normally placed between the surface of the body 10 and the wall of the mold cavity, to fix the thickness of the opening 35. Step iii) consists of filling the interior of the opening 35 with melted wax filling the same and around the holders 36. After the wax hardens, the structure of the mold 34 is removed. Note the sections of the mold structure 34a and 34b and the line from them 34c.

Figures 8 and 8a, related to step ii) above, show the sections of the closed mold 40 and 41 with a line starting from them 42. A cavity of the mold 33 is formed and the preformed nuclear body 10 is placed in that cavity with holders or spacers 36, which can be attached to the body of the mold, as in points 36a. A precise opening is formed in this manner around the body 10. A peripheral recess 46 sunk into the body of the mold extends around the body in a plane 44 and intersects the surfaces of the body corresponding to the last front wall of the head, intermediate to the sensitive spot, back wall of the head, upper wall of the head and base. See Figure 5. Plane 44 roughly separates the head. A support rib 144 will thus be formed integrally to the head, on its inner side, as seen in Figure 3.

Figure 9 corresponds to step iii) above and shows the wax coating 11 formed by the reception of melted wax within the opening 35, through the port 45 in the section of the mold 40, in Figure 8. The recess 46 is also full of wax. The holders or spacers 36 are removed, to produce the openings 36a in the wax coating.

Figure 10 corresponds to step b) above and shows the formation of the ceramic coating in layers 12 around the ceramic coating, by successive dips in a hydrated ceramic mix, as the mixtures shown. The liquid mixture fills the openings 36a, as well as the 12a. The ceramic coating 12 is allowed to harden and thus the solid ceramic holders 12 aa are formed in this manner, to place the core 10 when the wax is removed.

Figure 11 corresponds to steps c) and d) above and shows the ceramic coating 12 and core 10 placed there, after the wax is removed, to form an opening 13 therebetween. The ceramic holders 12a are formed during the dip formation of 12. The metal melted like steel, then melts into the opening, through the port 47 formed in the liner 12, to form the metal head. Finally, the outer skin 12 is fractured and removed, together with the holders 12a.

An opening or openings 16 as described above are formed in the rear wall of the head to provide access to the interior of the head to fracture and remove the nuclear core 10. Small openings formed in the metal wall as by the holders 36 and the corresponding ceramic holders 12a can be welded closed. If desired, the holder 36 can be formed integrally with the ceramic core 10.

In Figure 7, two inlet ports 16 in the rear wall are formed, on opposite sides of the vertical plane 44. Said ports are generally placed rearward of two concave recesses 50 and 51 formed in the base wall, on opposite sides. from a downward convex central ridge 52 extending from the front to the rear, at generally the same level. Plane 44 bisects that edge. The ports 16 also rest just above the level of the level of the rear wall 53. The recesses 50 and 51. the edge 52 and the level 53 may take the form, advantageously, described in the United States Patent Application serial number 08. / 263,970 filed on June 29, 1994, hereby incorporated by reference. See also Figure 12 hereof, showing the bottom (base area) of the latter, and with ports 16 formed in the lower rear wall. See also arrow 150 connected to the head. The ports 16 can not be seen when the head is seen from its top side. Ports 16 can be closed with welding, if desired.

The metal golf club head described has a wall structure defining an anterior wall, a heel, a tip, a rear wall, a base and an upper wall, said head having at least one transversal opening formed in said posterior wall in one level above the base and to rest below a rear portion of the top wall.

Claims

The claims are: 1. In the method for forming a metal head for hollow golf club having a wall structure defining an anterior wall, a heel, a tip, a rear wall, a base and an upper wall, the steps including: a) providing a core formed as a club head, preformed and covered with a wax coating, the wax coating covering the core area of the core, the thickness of the wax coating corresponding to the desired thickness of the structure of the walls of the head, b) forming a ceramic coating around the wax coating, c) removing the wax coating by melting the wax, to thereby form an opening between the ceramic coating and the body nuclear, d) and melt molten metal within the aperture, to thereby form the wall structure that extends around the nuclear core including the core area of the nuclear core, while that the entrance structure is formed and maintained through the wall structure and spaced from the base and allowing the wall structure to solidify to form the head, e) remove the ceramic lining from the wall structure and remove the nuclear core of the inside of the head solidified by the input structure.
2. - The method of claim 1 wherein said nuclear core is ceramic.
3. - The method of claim 1 wherein said port is formed through said rear wall of the head.
4. - The method of claim 1 wherein said port structure is formed to have a total size substantially smaller than that of the size of said base.
5. - The method of claim 1 wherein said port structure is formed as multiple ports through said rear wall of the head.
6. - The method of claim 1 including closing said port structure by providing and coupling a metal closure structure on said door structure.
7. - The method of claim 5 which includes closing said multiple ports by providing and coupling metal closures on said multiple ports.
8. - The method of claim 1 including providing spacer means for extending into said cavity between said ceramic coating and said nuclear core.
9. - The method of claim 1 wherein said base is formed to define an average edge and two concave recesses on opposite sides of said edge, said multiple ports formed rearwardly of said concave recesses.
10. - The method of claim 1 wherein said nuclear core is provided to define an elongated recess sunk into the surface of the nuclear core and corresponding to an elongated support rib by being formed by said head wall structure on the underside thereof.
11. - The method of claim 10 including the formation of said multiple ports to extend through said rear wall of the head on opposite sides of a plane defined by said support rib.
12. - The method of claim 1 including providing multiple ceramic holders for positioning the nuclear body to extend into said opening between said nuclear core and said ceramic coating.
13. - The method of claim 12 wherein said holders are provided during the formation of said ceramic coating around the wax coating.
14. - The method of claim 1 wherein said nuclear core covered with the wax coating is provided by: i) providing a preformed nuclear core as referred to and having the general shape of the head, ii) placing said core within a cavity formed by the mold structure, thus providing an initial opening around the core, iii) and filling with wax within the initial opening to cover the core and to form the wax coating.
15. - The method of claim 14 including the formation of elongated recesses sunk into the surface of the nuclear core and corresponding to an elongated support rib by being formed by said head wall structure on the inner side thereof.
16. - The method of claim 15 including the formation of said supporting rib to extend substantially in a cycle extending back and forth with respect to the wall structure of the head to be formed.
17. - The golf club head produced by the method of claim 1.
18. - The golf club head produced by the method of claim 15.
19. - A hollow golf club head having a wall structure defining a front wall, a heel, a tip, a rear wall, a base and an upper wall, said head having at least one opening formed in said rear wall level above the base and to rest under a posterior portion of the upper wall.
20. - The head of claim 19 having two of said openings in said rear wall.
21. - The head of claim 19 wherein said openings have transverse areas smaller than? 5 square inches.
22. - The head of claim 19 including a circular rib integral with the front, top and rear walls and on the inner sides thereof.
23. - The head of claim 20 including a circular rib integral with the upper, front and rear walls and the inner sides thereof, said rib defines a vertical plane passing between said two openings.
24. - The head of claim 19 wherein said opening is formed in said back wall during the formation of the head and said opening is subsequently closed, to provide an outer surface of the relatively smooth back wall.
25. - The head of claim 19 wherein said opening is closed, after forming to provide an outer surface of the relatively smooth back wall. ABSTRACT OF THE INVENTION In the method for forming a metallic and hollow golf club head having a wall structure defining a front wall, a heel, a tip, a rear wall, a base and an upper wall, the steps that include providing a core covered by a wax coating, the thickness of the wax coating corresponding to the desired thickness of the wall structure, forming a ceramic coating around said wax coating; remove the wax coating by melting the wax, to thereby form an opening between the ceramic coating and the core and melt molten metal into the opening, to thereby form the wall structure that extends around the core and at the base, while an entry structure is formed and maintained through the wall structure and separated from the base, and allow the wall structure to solidify to form the head; remove the ceramic coating from the wall structure and remove the nuclear core from the inside of the solidified head and through the entrance structure.