GB2268693A

GB2268693A - Golf club head.

Info

Publication number: GB2268693A
Application number: GB9314589A
Authority: GB
Inventors: Kenneth Victor Viljoen
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-07-14
Filing date: 1993-07-14
Publication date: 1994-01-19
Also published as: GB9214884D0; GB9314589D0

Abstract

The golf metal wood head has a face with a striking surface 12 for striking a golf ball, a domed back section 14 located behind the face and a hose 16 to which the end of a shaft is connected. The face and hosel are forged in one piece and the one piece assembly of face and hosel is then fixed to the back section by welding. The hosel extends into the head and may be drilled to take the shaft. The interior may be foam filled and rearwardly extending internal ribs provided on the front face. <IMAGE>

Description

GOLF CLUB METAL WOOD HEAD BACKGROUND TO THE INVENTION THIS invention relates to a golf club head, and in particular to the head of a so-called metal wood.

Metal woods have in recent years become extremely popular amongst golfers. Generally, the head of the club has a face, a domed back section extending rearwardly from the face, and a hollow hosel into which the end of the club shaft is fixed. The face and back section form a hollow body into which a foam material such as polystyrene is introduced through the hosel during manufacture of the head.

In the majority of known designs, the face, back section and hosel are formed in one piece of metal by an investment casting procedure. In another known design, the face is a separate investment casting which is secured to the back by welding. A serious disadvantage of investment cast metal wood heads is the fact that investment cast metals tend to be rather hard and afford the player little "feel" when the face of the club head strikes a golf ball. The problem is compounded by the fact that the hosel, which is the only link between the shaft and the head, is also investment cast and this further detracts from the "feel" which the player experiences during play.

SUMMARY OF THE INVENTION According to one aspect of the present invention, a golf metal wood head comprises a face having a striking surface for striking a golf ball, a domed back section located behind the face and a hosel to which the end of a shaft is connectable, wherein the face and hosel are forged in one piece and the one piece assembly of face and hosel is fixed to the back section.

In this specification, the term "forging" includes hot stamping.

The back section may be of investment cast construction, but is preferably of forged construction. In the latter case it may comprise two or more forged components fixed together. In each case it is preferred that the one piece forged assembly of face and hosel includes a flange extending rearwardly from the periphery of the face and the one piece assembly is welded to the back section at the rearward edge of the flange. In this arrangement, the rearward edge of the flange can be formed with a rebate, the back section having a leading edge that is received by the rebate.

To achieve a degree of perimeter weighting, it is preferred that the face and hosel be of thicker construction than the domed back section.

According to another preferred feature of the invention, the one-piece assembly of face and hosel and the back section define an internal cavity, the hosel extending into the cavity. The hosel may include an internal bore formed therein by drilling.

In one embodiment, the hosel includes an indentation formed therein during forging, the depth of the indentation being such that it is intersected by the internal bore during the drilling of that bore, with result that a transverse opening is formed in the hosel and the bore of the hosel is placed in communication with the cavity. In another embodiment, the bore in the hosel extends to the operatively lower end of the hosel where it communicates with the cavity. In either case, the internal cavity can filled with a settable filler material through the hosel.

According to a preferred feature of the invention, the face has an operatively rear surface provided with integral strengthening ribs.

According to a second aspect of the invention, there is provided a method of making a golf metal wood head, the method comprising the steps of forging a face and a hosel in one piece, constructing a domed back section, and fixing the back section to the forged, one piece assembly of face and hosel.

The hosel may be forged solid and thereafter be drilled out to form an internal bore.

this specification, the term "forging" includes hot stamping.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings.

Ir the drawings: Figure 1 shows a plan view of a golf metal wood head of the invention; Figure 2 shows an end elevation of the wood head in a direction looking at the toe of the head; Figure 3 shows a plan view of the one piece forged assembly of face and hosel; Figure 4 shows a rear view of the assembly of Figure 3, i.e. looking in the direction of the arrow 4 in Figure 3; Figure 5 shows a cross-section at the line 5-5 in Figure 3; Figure 6 shows a cross-section at the line 6-6 in Figure 1; and Figures 7A and 7B show the encircled zone in Figure 6 before and after welding.

DESCRIPTION OF EMBODIMENTS The illustrated golf metal wood head 10 has a face 12, a domed back section 14 and a hosel 16. The face 12 has a front ball striking surface 18 with the usual array of parallel grooves 19 to impart spin to the struck golf ball. The hosel 16 is hollow and is dimensioned to receive the lower end of a conventional club shaft (not shown), which is fixed by conventional means into the hosel in the fully assembly metal wood.

In accordance with the present invention, the face 12 and hosel 16 are hot forged in one piece. The forged, one piece assembly 20 is illustrated in Figures 3 to 5. As will be evident from these Figures, there is a flange 22 which extends rearwardly from the periphery of the face 12. The flange 22 terminates at a stepped rebate 24. Referring in particular to Figure 3, it will be seen that the flange includes a rearwardly extended portion 26 where the hosel 16 meets the flange.

As shown in Figures 4 and 5, the. hosel has a lower portion 28 which extends downwardly behind the face 12 at a position towards the heel 30 of the head 10. The hosel is forged solid in the forging process and is provided with an indentation 32. After the forging process, an axial bore 34 is drilled right through the hosel. The depth of the indentation 32 and the diameter of the bore 34 are such that the bore intersects the indentation, creating a transverse opening 36 that vents behind the face 12.

A series of ribs 38 is forged integrally with the rear surface 40 of the face 12 during the forging process. The ribs extend from top to bottom of the rear surface 40, between the upper and lower sections of the peripheral flange 22.

The domed back section 14 may in some embodiments be of one piece, investment cast construction. However, in the preferred embodiment illustrated in the drawings, the back section 14 is of one piece hot forged construction. As an alternative to a one piece construction, the back section 14 can be assembled from two hot forged components which meet and are welded to one another along the line indicated by the numeral 44 in Figure 2.

Irrespective of the construction of the back section 14, it will be noted in Figure 6 that the wall thickness of this section is considerably less than that of the face 12 or the flange 22. The leading edge 46 of the back section locates in the rebate 24 at the edge of the flange 22 and, as seen in Figure 7A, is chamfered.

The chamfer creates a V-shaped groove 48 in which welding 50 takes place to secure the back section to the one piece assembly of face and hosel. Excess weld is ground off to provide a smooth surface.

As illustrated in Figure 6, the back section 14 and face 12, in combination, define an internal cavity 50. This cavity is filled with a suitable filler (not shown), such as polystyrene or polyurethane foam, as a final step in the construction of the club head.

The filler is poured in unset form into the cavity 50 through the hosel 16 and transverse opening 36 and is thereafter allowed to set.

The illustrated metal wood head has a number of advantages when compared to known metal wood heads. One important advantage arises as a result of the forged nature of the hosel 16, which is the only link between the club head and the shaft and, ultimately, the player. When a golf ball is struck by the striking surface 18, the impact shock and resulting vibrations are transferred to the shaft through the hosel. The fact that the hosel 16 is of forged construction, as opposed to being of investment cast construction as in prior art metal wood heads, means that it has better shock and vibration damping characteristics. This leads to a desirable, softer "feel" for the player.

When compared to heads which are totally of investment cast construction, the head 10 of course enjoys the further advantage that the face is itself of forged construction. Once again this contributes to a softer "feel" for the player.

Yet another advantage arises from the provision of the rearwardly extending flange 22 which has considerable mass when compared to the back section. The flange 22 in effectively provides perimeter weighting for the face. It is a well-established fact that perimeter weighting of a golf club head is preferred by many golfers to a classical weight concentration directly behind the striking zone of the face.

Added to this, the fact that the flange extends some distance to the rear behind the face means that the welding of the face to the back section also takes place well behind the face. Thus the grinding operation which is necessary to provide a smooth finish after welding is well removed from the striking surface 18, so there is little danger of material inadvertently being removed from the face 12 and the performance of the club head being detrimentally affected by excess thinning of the material in the face. Likewise there is little danger of the grooves 19 being affected by the grinding operation.

Also, the location of the weld 50 well away from the impact area renders the integrity of the weld less likely to be detrimentally affected by the impacts which take place when golf balls are struck.

The hot forging of the one piece assembly of face 12 and hosel 16 permits the incorporation of the reinforcing ribs 38 which will, it is believed, improve the strength of the face 12.

In conventional investment cast heads, the hosel does not extend into the head and the point at which the lower end of the hosel meets the head is considered to be a weak point at which failure can take place.

In the club head 10, the hosel actually enters the cavity 50 and it is believed that this will reduce the chances of hosel failure. In this connection it should be noted that in an alternative construction, the lower end of the hosel may, as before, enter the cavity, but terminate above the flange 22. The hosel would again be solid after the forging operation and thereafter would be drilled out to form a passage leading into the cavity 50 for the introduction of settable filler material. Thus in this case there would be no need to forge the hosel with an indentation 36 as described above.

The club head 10 may be constructed from any suitable metal, such as stainless or mild steel or any of the alloys currently used for golf club head construction.

It was mentioned previously that the back section 14 could be of cast construction or forged in one or more parts that are subsequently connected together. As further alternatives, it is within the scope of the invention for the back section to have other constructions, for instance a solid or hollow moulded plastics or moulded carbon fibre construction.

With non-metallic constructions of the back section, the forged face and hosel assembly can clearly not be welded to the back construction. In such cases, the forged assembly can be fixed to the back section by any other convenient method, for instance with the use of appropriate adhesives.

Claims

ClAIMS

1.

A golf metal wood head comprising a face having a striking surface for striking a golf ball, a domed back section located behind the face and a hosel to which the end of a shaft is connectable, wherein the face and hosel are forged in one piece and the one piece assembly of face and hosel is fixed to the back section.

2.

A golf metal wood head according to claim 1 wherein the back section is of investment cast construction.

3.

A golf metal wood head according to claim 1 wherein the back section is of forged construction.

4.

A golf metal wood head according to claim 3 wherein the back section comprises two or more forged components fixed together.

5.

A golf metal wood head according to any one of claims 2 to 4 wherein the one piece forged assembly of face and hosel includes a flange extending rearwardly from the periphery of the face and the one piece assembly is welded to the back section at the rearward edge of the flange.

6.

A golf metal wood head according to claim 5 wherein the rearward edge of the flange is formed with a rebate and wherein the back section has a leading edge that is received by the rebate.

7.

A golf club metal wood head according to claim 5 or claim 6 wherein the face and hosel are of thicker construction than the domed back section.

8.

A golf club metal wood head according to any one of the preceding claims wherein the one-piece assembly of face and hosel and the back section define an internal cavity, the hosel extending into the cavity.

9.

A golf metal wood head according to claim 8 wherein the hosel includes an internal bore formed therein by drilling.

10.

A golf metal wood head according to claim 9 wherein the hosel includes an indentation formed therein during forging, the depth of the indentation being such that it is intersected by the internal bore during the drilling of that bore, with result that a transverse opening is formed in the hosel and the bore is placed in communication with the cavity.

11.

A golf metal wood head according to claim 9 wherein the bore in the hosel extends to the operatively lower end of the hosel where it communicates with the cavity.

12.

A golf metal wood head according to any one of claims 8 to 11 wherein the internal cavity is filled with a settable filler material.

13.

A golf metal wood head according to any one of the preceding claims wherein the face has an operatively rear surface provided with integral strengthening ribs.

14.

A method of making a golf metal wood head, the method comprising the steps of forging a face and a hosel in one piece, constructing a domed back section, and fixing the back section to the forged, one piece assembly of face and hosel.

15.

A method according to claim 14 wherein the domed back section is made of metal and is welded to the forged, one piece assembly of face and hosel.

16.

A method according to claim 15 wherein the back section is welded to the one piece assembly of face and hosel at the rear edge of a flange which extends rearwardly from the periphery of the face.

17.

A method according to claim 16 wherein the one piece assembly of face and hosel includes a rebate at the rear edge of the flange, the back section has a chamfered leading edge which is received in the rebate and welding takes place in a groove defined by the chamfer and rebate.

18.

A method according to any one of claims 14 to 17 wherein the hosel is forged solid and is thereafter drilled out to form an internal bore.

19.

A method according to claim 18 wherein the hosel is forged with a transverse indentation therein, the depth of the indentation and the diameter of the hole which is drilled in the hosel being chosen for the drilled bore to intersect the indentation and creating an opening leading transversely from the bore.

20.

A method according to claim 18 wherein the bore extends right through the hosel so that the hosel has an open lower end.

21.

A method according to either one of claims 19 or 20 wherein the back section and the one piece assembly of face and hosel define a hollow internal cavity, the method comprising the further step of filling the internal cavity with a settable substance, filling taking place through the hosel.

22.

A method according to any one of claims 14 to 21 comprising the step of providing the face with integral strengthening ribs during the forging of the one piece forged assembly of face and hosel.

23.

A golf club metal wood head substantially as herein described with reference to the accompanying drawings.

24.

A method of making a golf club metal wood head substantially as herein described with reference to the accompanying drawings.