EP0400277B1 - Head of a golf club and method of manufacturing the same - Google Patents

Description

The present invention relates to a golf club head comprising in particular a striking face.

GB-A-267 755, AU-A-211 781, US-A-4 618 149 and GB-A-2 184 951 describe composite golf club heads, that is to say whose striking face is made of a material different from that of the rest of the head.

In known golf heads, a plate, generally metallic, attached to a hollow or solid body, made of wood or synthetic material, is used for the striking face. The metal plate is most often fixed to the body by screwing, but it can also be glued or welded to it. However, these assembly methods are not always satisfactory from the point of view of their longevity, in particular taking into account violent mechanical stresses and the environment (thermal variations, UV radiation, possible contact with weed killers, etc.), especially when the body is made of a synthetic material.

In addition, in the case of an assembly by screwing, the need to make pilot holes in the body and to tap them complicates the manufacturing process and limits the possible production rates.

According to document US-A-4 438 931, a golf club head is known comprising a hollow body defining an interior volume, a closure element cooperating with this body so as to close the interior volume of it. ci, a filling material for at least part of the interior volume of the body. In this document, the body and the closure element are joined by welding and the material plays no role in their joining.

The subject of the present invention is a composite golf club head, the structure of which avoids the need for screwing, welding or bonding of the striking face to the body, which provides an assembly of very long service life and which is easily industrializable for mass production.

To this end, the golf club head of the invention comprises: a hollow body, made of a first material, defining an open interior volume; a closure element cooperating with this body so as to close the internal volume thereof, this closure element being made of a second material, different from the first, and having on the external side a surface forming the striking face of the club; and a filling material for at least part of the interior volume of the body, this material contributing to the joining of the closure element to the body.

• l'élément d'obturation coopère avec le corps par venue en butée vers l'extérieur contre des moyens périphériques, continus ou discontinus, d'appui prévus sur le corps ;
• il est prévu une surface transversale interne divisant le volume intérieur du corps creux de manière à réduire le volume du matériau de remplissage dans celui-ci ; cette surface transversale interne peut notamment être définie par une paroi rapportée, ou bien par la surface libre d'un matériau de comblement partiel préalablement introduit dans le corps creux ; dans le premier cas, le corps peut être formé de deux demi-corps assemblés de part et d'autre de la paroi rapportée définissant ladite surface transversale interne ;
• il est prévu des moyens de maintien en position de l'élément d'obturation avant introduction du matériau de remplissage dans le corps creux ; ces moyens de maintien peuvent être des moyens élastiques sollicitant l'élément d'obturation contre l'appui périphérique du corps, notamment des moyens élastiques comprimés entre ladite surface transversale interne et la surface interne de l'élément d'obturation ;
• il est prévu des moyens de centrage latéral de l'élément d'obturation par rapport à la périphérie de l'ouverture du corps creux ;
• l'élément d'obturation est pourvu sur sa face interne de moyens d'ancrage dans la masse du matériau de remplissage ;
• le volume intérieur du corps communique avec un emmanchement latéral creux par lequel est introduit le matériau de remplissage avant mise en place du manche sur la tête du club ;
• le matériau de remplissage est choisi dans le groupe comprenant les polyamides, les polyesters, les polyéthylènes et leurs combinaisons, et/ou il est au moins partiellement formé d'un matériau élastomère ;
• le matériau de remplissage est au moins partiellement formé d'un matériau élastomère.

According to a number of advantageous provisions:

• the closure element cooperates with the body by abutting outwardly against peripheral means, continuous or discontinuous, of support provided on the body;
• an internal transverse surface is provided dividing the internal volume of the hollow body so as to reduce the volume of the filling material therein; this internal transverse surface can in particular be defined by an attached wall, or else by the free surface of a partial filling material previously introduced into the hollow body; in the first case, the body can be formed of two half-bodies assembled on either side of the attached wall defining said internal transverse surface;
• means are provided for holding the closure element in position before introduction of the filling material into the hollow body; these holding means can be elastic means urging the obturation element against the peripheral support of the body, in particular elastic means compressed between said internal transverse surface and the internal surface of the obturation element;
• means are provided for lateral centering of the closure element relative to the periphery of the opening of the hollow body;
• the closure element is provided on its internal face with anchoring means in the mass of the filling material;
• the internal volume of the body communicates with a hollow lateral fitting by which the filling material is introduced before the sleeve is placed on the head of the club;
• the filling material is chosen from the group comprising polyamides, polyesters, polyethylenes and combinations thereof, and / or it is at least partially formed from an elastomeric material;
• the filling material is at least partially formed of an elastomeric material.

The invention also relates to a method of manufacturing a golf club head, comprising the steps of: producing an open hollow body; closing of this hollow body by a closure element having on the external side a surface forming the striking face of the club; and introduction into at least part of the interior volume of the body of a filling material contributing to the attachment of the closure element to the body. The constituent materials of the hollow body and of the closure element may be identical or, preferably, different.

Very advantageously, the quantity and the pressure of the filling material are chosen so as to press the sealing element against peripheral means, continuous or discontinuous, of support provided on the body.

• mise en place, avant introduction du matériau de remplissage, d'une paroi rapportée définissant une surface transversale interne divisant le volume intérieur du corps creux de manière à réduire le volume du matériau de remplissage dans celui-ci ;
• comblement partiel du corps creux avant introduction du matériau de remplissage, de manière à réduire le volume du matériau de remplissage introduit ensuite ; et/ou
• avant l'étape de fermeture du corps creux par l'élément d'obturation ou en même temps que celle-ci, mise en place de moyens de maintien en position de l'élément d'obturation.

Preferably, this method also comprises steps of:

• establishment, before introduction of the filling material, of an attached wall defining an internal transverse surface dividing the interior volume of the hollow body so as to reduce the volume of the filling material therein;
• partial filling of the hollow body before introduction of the filling material, so as to reduce the volume of the filling material subsequently introduced; and or
• before the step of closing the hollow body by the shutter element or at the same time as the latter, fitting means for holding the shutter element in position.

We will now describe examples of implementation of the invention, with reference to the accompanying drawings (it will be noted that in all the figures, the same reference numerals denote similar elements).

Figure 1 is a sectional view of a golf club head according to the invention.

Figures 2 to 8 explain the different stages of a method of manufacturing the golf club head of FIG. 1.

Figure 9 is a front view of a golf club head according to the invention, showing the manner in which the lateral centering of the striking face is obtained.

FIG. 10 illustrates a second embodiment of the golf club head of the invention.

Figures 11 and 12 illustrate how to make a continuous joint between body and striking face during manufacture.

Figures 13 and 14 illustrate a first embodiment of the peripheral support of the striking face on the body.

Figures 15 and 16 illustrate a second embodiment of the supports of the striking face against the body.

FIG. 17 illustrates a third embodiment of the support of the striking face against the body.

Figure 18 is a front view showing an alternative embodiment allowing, in a combined manner, the support of the striking face against the body and the relative lateral centering of these two elements.

Figures 19 to 22 illustrate an alternative assembly of the golf club head of the invention.

In Figure 1 there is shown, in cross section, a golf club head according to the invention.

This essentially comprises a hollow body 10, for example consisting of two half-bodies 11 and 12, defining an interior volume 30 open at the front part (the front part being the part, located on the right in the figure, on the side of which the golf club head will hit the ball).

This internal volume 30 is closed by a shutter element 20 whose edge 21 abuts outwards of the volume 30 against an internal shoulder 13 of a flange that the body 10 has around the opening of the volume 30. The external surface 22 of this closure element will constitute the striking surface of the club, and it is shaped in a known manner, that is to say very slightly convex and striated, as can be seen for example in the front views Figures 9, 12 and 18.

The internal volume 30 of the body 10 is partially or completely filled with a curable material injected or poured inside the body.

In the example of FIG. 1, the filling material does not occupy the entire interior volume 30, which makes it possible to reduce the quantity. This is obtained by defining an internal transverse surface 40, for example (but not necessarily, as will be explained below) by means of a transverse attached wall 41 assembled between the two half-bodies 11 and 12. The volume 31 located behind this wall (that is to say on the side opposite the closure element 20) will be empty, while the volume 32 located on the other side will receive the filling material.

Very advantageously, this filling material is injected or poured through the hollow fitting 14 which, after manufacture of the club head, will receive the club handle. This hollow fitting, which is in one piece with the half-body 12, communicates with the closed interior volume defined by the transverse wall 41, the closure element 20 and the half-body 12: it is in this closed volume that the 'the filling material will be injected or poured.

The main role of the filling material injected into the volume 32, that is to say behind the obturation element 20, is, after hardening, to hold in place and secure to the body 10 the obturation element 20, thus making it possible to obtain an assembly of these two elements without screwing, bonding or welding, which is nevertheless easy to implement and ensures a very long service life.

To keep the sealing element 20 in place during the pouring and setting of the filling material, an elastic member 50 can be provided, for example a block of elastomeric material, compressed between the wall 41 and the striking face 20 and who will tackle the latter against the shoulder 13 of the body 10.

This holding means is not, however, essential, the closure element 20 being able for example to be held in place on the internal shoulder 13 of the body 10 simply by gravity during the setting of the material, filling and setting. then striking face down.

Furthermore, the quantity and the pressure of the filling material can be chosen so that the pressure developed in the volume 32 during the injection presses the closure element 20 against the shoulder 13; one can also provide for the filling material an expandable material (in particular a material comprising an elastomeric component) so as to develop in the cavity 32 an internal pressure during the polymerization of the material.

Among the materials which can be used for filling the cavity 32, a material more particularly chosen belongs to the group comprising polyamides, polyesters, polyethylenes and their combinations.

Among the polyamides, mention may in particular be made of Pebax® , Grilamid® and Vestamid® (elastomeric polyamides), among the polyesters Arnitel® and Hytrel® (polyether esters) and among the polyethylenes Surlyn® (acrylic polyethylene ).

Advantageously, the closure element 20 can also be provided with anchoring projections 60 in the mass of the filling material, for example projections in the form of branches, as illustrated in FIG. 1. The ends of these branches can optionally come to bear against the wall 41 (or the bottom of the body, in the absence of such a wall).

If the anchoring branches 60 are made of elastic material and come to bear on the wall or the bottom, they can advantageously supplement or replace the holding function provided by the intermediate element 50. These branches can however be made of non-elastic material, for example in a ceramic material.

Figures 2 to 8 illustrate the different stages of one of the possible methods of making the head. Figure 1 club.

First of all (FIG. 2), the body 10 is assembled by joining the half-bodies 11 and 12 with the interposition of the wall 41 defining the internal transverse surface 40.

Then (FIGS. 3 and 4) the intermediate elastic pad 50 is placed against the wall 41 and the obturation element 20, the face 22 of which faces outwards, is introduced into the cavity 13, by slightly tilting it. of the cavity 13.

Once the closure element 20 is fully inserted into the body 10, it is straightened so as to bring it back to its normal position (FIGS. 5 and 6), that is to say with the edge 21 resting against the shoulder 13 of the body and face 22 outwards. Provisional maintenance of the closure element 20 in this position (which is the final position) is ensured by the intermediate elastic buffer 50 compressed between the wall 41 and the closure element 20, in this example.

We can then (Figures 7 and 8) pour or inject the material through the fitting 14 which, as indicated above, communicates directly with the cavity 32 defined inside the body. The filling material thus injected or poured will, after hardening, lock in position the obturation element, thus ensuring its final attachment to the body.

FIG. 9 illustrates means allowing, in addition, the relative lateral centering of the striking face 22 with respect to the body 10. This centering is ensured by suitable pins formed at the inner periphery of the rim of the opening of the body 10 ( stud 15) and / or at the outer periphery of the closure element 20 (stud 23).

FIG. 10 illustrates a variant of the production method in which the internal transverse surface 40 is no longer defined by an attached wall, but by the free surface 34 of a filling material 31 poured into the bottom of the body 10 (this this being arranged with its opening facing upwards during this operation). This limits the amount of filling material properly said introduced into the remaining volume 32, in the same manner as when the transverse surface 40 was defined by an attached partition.

FIGS. 11 and 12 illustrate an embodiment detail in which it is ensured that there remains, in transverse direction, a gap 35 between the inner periphery of the opening of the body 10 and the outer periphery of the closure element 20. By injecting the filling material under pressure into the cavity 32, it will penetrate into this interval 35, which makes it possible to create a continuous peripheral seal 36 between the body 10 and the sealing element 20, around the face of strike 22, as illustrated in figure 12.

FIGS. 13 to 17 illustrate different alternative embodiments of the supports 21, which allow the closure element 20 to abut against the shoulder 13 of the body 10.

In Figures 13 and 14, this support 21 is constituted by lateral projections 21 of the closure element 20, extending outward. These projections 21 may be in one piece with the closure element 20, or may consist of tabs attached to the latter.

In FIGS. 15 and 16, the supports consist of recessed tabs formed in the thickness of the closure element.

In either case (protruding or recessed element), there can be either a plurality of supports distributed around the periphery of the closure element, as illustrated in the various figures, or a continuous peripheral support; it will be noted however that only the plurality of insulated supports makes it possible to produce a peripheral seal 36 as illustrated in FIGS. 11 and 12.

One can also provide, as illustrated in FIG. 17, a conical adjustment between the body 10 and the closure element 20. The homologous contact surfaces 13, 21 are then cooperating conical surfaces. It will be noted that, depending on the case, a blocking adjustment can also be provided (force fitting of the closure element 20 in the opening 10) body than non-blocking.

FIG. 18 illustrates an embodiment in which these are the same elements which ensure both the function of support stop and of centering of the striking face relative to the body: the support elements are elements such as those illustrated in FIG. 16, that is to say formed by removal of material in the thickness of the closure element 20, and they come into abutment against projections 15 of the body extending transversely inwards ( in the manner of the projections 15 of FIG. 9), which themselves adjust against the homologous surface 24 (FIG. 16) of the edge of the recess made to form the support tab 21.

Figures 19 to 22 illustrate a variant of the method of producing the club head of the invention.

In this variant, we start by mounting the shutter element 20 in the front half-body 12, then we assemble the rest of the head by putting in place the elastic pad 50, trapping it by placing the internal wall 41, then closing the assembly by fitting the rear half-body 11.

In this variant, it is also possible to avoid using the intermediate elastic element 50 by forcibly mounting the closure element 20 in the front half-body, which avoids having to temporarily hold the closure element. in place in the body by means of the elastic element 50.

We can in particular provide that this forced mounting will take place at the outer edge 25 of the supports 21, the overall dimension of the closure element being chosen slightly greater than the internal dimension of the opening of the half-body. 12. Such a force fit with clamping at the level of the supports (which also allows lateral centering), allows the gap 35 to remain which will allow the continuous peripheral seal to be produced when the filling material fills it.

As a variant or in addition, centering can also be carried out, as can be seen in the perspective view in section of FIG. 22, by pins 15, 23 formed respectively on the body and / or the closure element, as illustrated in FIG. 9.

It will be noted that the technique of the invention can be applied to the production of all types of golf club, both "wood" and "irons".

Claims (18)

1. A golf club head comprising:

   - a hollow body (10) defining an open internal volume (30),

   - a sealing element (20) interacting with this body so as to close the internal volume of the latter, this sealing element having on the external side a surface (22) forming the striking face of the club, and

   - a material (32) for filling at least a part of the internal volume of the body,

   characterised in that the sealing element interacts with the body by coming into abutment towards the outside against continuous or discontinuous peripheral means of support (13) provided on the body and is held in place against said means by the filling material (32) which contributes to the fixing of the sealing element to the body.
2. The golf club head according to Claim 1, comprising moreover an internal transverse surface (40) dividing the internal volume of the hollow body so as to reduce the volume of the filling material in the latter.
3. The golf club head according to Claim 2, in which the internal transverse surface (40) is defined by an added wall (41).
4. The golf club head according to Claim 3, in which the body (10) is formed from two half-bodies (11, 12) assembled on either side of the added wall (41) defining said internal transverse surface.
5. The golf club head according to Claim 2, in which the internal transverse surface (40) is defined by the free surface (34) of a material (31) for partial filling up introduced into the hollow body previously.
6. The golf club head according to one of Claims 1 or 2, comprising moreover means (50) for holding the sealing element in position before introduction of the filling material into the hollow body.
7. The golf club head according to Claim 6 in dependence on Claim 1, in which the holding means (50) are elastic means stressing the sealing element (20) against the peripheral support (13) of the body.
8. The golf club head according to Claim 6 in dependence on Claim 2, in which the elastic holding means are compressed between said internal transverse surface (40) and the internal surface of the sealing element (20).
9. The golf club head according to Claim 1, comprising moreover means (15, 23) for lateral centring of the sealing element in relation to the periphery of the opening of the hollow body.
10. The golf club head according to Claim 1, in which the sealing element is provided on its internal face with means (60) for anchoring in the mass of the filling material (32).
11. The golf club head according to Claim 1, in which the internal volume (30) of the body communicates with a hollow lateral shaft (14), via which the filling material (32) is introduced before the handle is put in place on the head of the club.
12. The golf club head according to Claim 1, in which the filling material (32) is chosen from the group comprising polyamides, polyesters, polyethylenes and their combinations.
13. The golf club head according to Claim 1, in which the filling material (32) is at least partially formed from an elastomeric material.
14. The golf club head according to Claim 1, in which the material of the hollow body is a material which is different to that of the sealing element.
15. A method of manufacturing a golf club head, comprising the following stages:

    - production of an open hollow body (10),

    - closing of this hollow body by a sealing element (20) having on the external side a surface (22) forming the striking face of the club, and

    - introduction into at least a part of the internal volume of the body of a filling material (32),

    characterised in that the quantity and the pressure of the filling material are chosen so as to lay the sealing element flat against continuous or discontinuous peripheral means of support (13) provided on the body so as to contribute to the fixing of the sealing element to the body.
16. The method according to Claim 15, comprising a stage of putting in place, before introduction of the filling material, of an added wall (41) defining an internal transverse surface (40) dividing the internal volume of the hollow body so as to reduce the volume of the filling material in the latter.
17. The method according to Claim 15, comprising a stage of partial filling up of the hollow body before introduction of the filling material so as to reduce the volume of the filling material introduced subsequently.
18. The method according to Claim 15, comprising a stage, preceding the stage of closing of the hollow body by the sealing element or concomitant therewith, of putting in place means (50) for holding the sealing element in position.

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