Golf club head with shell and additional element(s)

Abstract

A club head for a golf club is specified, which has an outer shell and one or more additional elements made of metal. The shell is manufactured of a composite material, in particular a fiber-reinforced plastic. The additional element(s) are each embedded at least partially in the composite material of the shell with a connection region. The connection region of the one or more additional elements is each formed by a laser-structured and / or multi-stepped surface. In addition, a golf club with such a club head and a method for manufacturing a club head are described.

Description

TECHNICAL FIELD

[0001] The present invention relates to a club head for a golf club and a golf club with such a club head. The invention also relates to a method for manufacturing such a club head.PRIOR ART

[0002] Golf is a widely practiced sport in which both the golfer's performance and the technological characteristics of the golf club are of central importance. From a technological perspective, it is important that the golf ball can be hit as accurately and precisely as possible toward the hole from a wide variety of situations. In the field of golf club development and design, one of the goals is therefore to improve both the accuracy of direction and the achievable distance of the shots. Another important factor in the development of golf clubs is the forgiveness of the golf club, and in particular the club head, i.e., the ability of the device to achieve sufficient directional accuracy or a good distance, respectively, even with a less than optimal shot.

[0003] In order to achieve optimal weight distribution in the club head with regard to the above-mentioned requirements and to positively influence the dynamics of the swing, weighting elements are often provided on or in the club head of golf clubs.

[0004] For example, document US 2015 / 0045130 A1 discloses a club head with weighting elements arranged on the outside of the club head and inside a damping element provided inside.

[0005] Document U.S. Pat. No. 9,333,390 B1 discloses a golf club head in which weighting elements can be inserted.

[0006] Document U.S. Pat. No. 10,213,665 B1 discloses hollow golf club heads with a recess on the underside for inserting disc-shaped weighting elements.

[0007] Furthermore, document US 2013 / 0085012 A1 discloses a golf club head with a hollow structure filled with a foam material and a metal striking plate attached to the outside.

[0008] Composite materials consisting of fiber-reinforced plastic material have been increasingly used in the manufacture of golf club heads for some time now. The advantage of such materials over conventionally used metals lies in particular in their weight. Composite materials can be used to manufacture golf club heads whose structure is many times lighter than that of conventional metal club heads. With the aid of weighting elements, a desired weight distribution can be adjusted even more precisely. By aligning the fibers appropriately, the force transmission and transfer within the club head can also be controlled and optimized with composite materials. Furthermore, composite materials can be used to form club heads with a wide variety of geometries. In club heads made of composite materials, the striking plate is usually formed from a metal plate.

[0009] For example, document U.S. Pat. No. 5,193,811 A discloses a golf club head with a body made of a fiber-reinforced material and a metal plate attached to it. Inside the body is a core made of a foam material and, in some embodiments, a weighting element.

[0010] Document U.S. Pat. No. 5,547,427 A discloses a golf club head with a hollow body that can be made of a fiber-reinforced thermoplastic material and filled with a foam material. At the front, the interior space formed by the hollow body is closed off with a striking plate. At the rear, the hollow body has a recess into which a weighting element is inserted.

[0011] Furthermore, document US 2023 / 0056990 A1 discloses a golf club head with a base body made of metal. The shell-like base body comprises an opening into which a part made of a fiber-reinforced plastic material is inserted.

[0012] One challenge with club heads whose base body is made of a fiber-reinforced plastic material is the connection of the additional metal elements, such as the weighting elements or the striking plate, to the composite material. Golf usually involves very high forces, as the golf ball is often struck by the club head with great force. When the golf ball is struck, which according to the rules takes place within a maximum of 239 microseconds, the ball is accelerated with up to 30,000 g. The golf club is decelerated by 2,000 to over 5,000 g. This places a very high strain on the connection between the weighting elements and the composite material that forms the club head structure. The high main load of the deceleration during the swing is superimposed by lateral accelerations, which occur in all directions as soon as the ball is hit outside the center of gravity of the club head, as well as further impact stresses upon contact with the ground. In addition, the connection is compromised by the strong vibrations of the structure after the impact and is subject to thermally superimposed stresses due to the different thermal expansions of the connection partners. The additional elements attached to or inside the golf club can thus detach from the composite material over time. The resulting gradual or sudden movement of the additional elements relative to the base body can lead to undesirable changes in the striking behavior, which can ultimately render the club head unusable. Additional elements that detach completely from the club head can also pose a hazard to the player.SUMMARY OF THE INVENTION

[0013] It is an object of the invention to provide a club head for a golf club made of a composite material, wherein one or more additional parts are held securely to the composite material for a long time.

[0014] This problem is solved by a club head comprising the features of claim 1. Claim 15 specifies a golf club with such a club head, and claim 16 specifies a method for manufacturing a club head. Further embodiments are specified in the dependent claims.

[0015] A club head for a golf club is therefore specified, comprising

[0016] an outer shell made of a composite material, in particular a fiber-reinforced plastic; and

[0017] one or more additional elements made of metal, each of which is at least partially embedded in the composite material of the shell with a connection region.

[0018] The connection region of the one or more additional elements is formed in each case by a laser-structured and / or multi-stepped surface.

[0019] By forming the connection region of the additional element(s) with a laser-structured and / or multi-stepped surface, the metal can bond particularly efficiently and permanently with the composite material of the shell. The laser structuring and / or the steps increase the total surface area of the connection region, whereby a stronger connection of the respective additional element to the shell is achieved. In particular, a matrix material of the shell can engage with the structure provided in the surface of the connection region and, if necessary, even engage behind and / or underneath it, resulting in a particularly strong connection between the shell and the additional element. In addition, the formation of the laser structuring and / or the steps can be adapted with regard to the forces usually acting on the club head in such a way that the detachment forces acting between the additional element and the shell, such as in particular shear, gravity, and tensile forces, are reduced. For this purpose, the steps can, for example, form undercuts in relation to the intended main direction of impact or form a surface perpendicular to the main direction of impact with a deviation of a maximum of 40°, preferably a maximum of 20°, in order to optimally absorb the forces usually acting on the connection region. The surface structures formed by laser structuring can also be geometrically adapted to the forces that typically occur in such a way that the forces are transferred as efficiently as possible and with minimal separation forces from the respective additional element to the shell and vice versa. It has been found that, for these reasons in particular, the laser-structured and / or multi-stepped surface can sustainably improve the connection of the additional element(s) to the shell with regard to frequent use. Thanks to the laser structuring or the multi-stepped surface, respectively, the number of detachments of additional elements from the shell could be significantly reduced in long-term tests.

[0020] The shell usually forms a base of the club head. The base of the club head refers to the component which absorbs and transfers the forces that are exerted on the club head usually by the golf club shaft or the so-called hosel onto the striking plate or in the opposite direction, and usually forms the main structure of the club head. The striking plate is usually attached to an outer side of the base body, which generally has an opening for inserting or attaching the club shaft or hosel, respectively. The base body also often forms the main shaping element of the club head.

[0021] The shell is understood to be a component that at least partially surrounds an interior space of the club head, i.e., it usually forms at least a part of an outer shell of the club head. In most cases, the shell comprises a certain curvature. Alternatively or additionally, the shell may also comprise corners and / or edges. Preferably, the shell forms a hollow body.

[0022] Advantageously, the shell covers at least 25%, even more advantageously at least 50%, and most advantageously at least 75% of the outer surface of the interior. It has been shown that the forces occurring during golf can be distributed and transmitted particularly advantageously via the club head if the shell covers such a large proportion of the outer surface of the interior. It is even more preferable for the shell to essentially completely enclose the interior of the club head, which means that, for example, there may be a relatively small opening for attaching the club shaft or hosel, but otherwise the interior is completely surrounded by the shell. This can achieve a flow of forces across the club head that is particularly beneficial for golf.

[0023] The club head usually forms the golf club together with the hosel, the golf club shaft, and the golf club grip. The hosel is the connecting piece at the top of the club head into which the shaft is inserted. The hosel can be designed as a separate component from the club head or can be formed by the club head itself.

[0024] The composite material of the shell can be, in particular, a fiber-reinforced plastic, whereby the plastic can be a thermoplastic, but preferably a thermosetting plastic, i.e., a duromer plastic. A composite material is understood here to be a bonded material consisting of two or more materials bonded together. The composite material generally has different properties than each of the individual materials. A composite material usually consists of a base material, referred to as a matrix, and a reinforcing material, such as for example a fiber. Preferred materials for a matrix material are thermoplastic materials such as polyether ether ketone (PEEK), thermosetting materials such as resins, etc. Examples of fibers include materials such as carbon fibers, glass fibers, aramid, Kevlar fibers, etc. The person skilled in the art is aware of a large number of suitable composite materials for the shell.

[0025] In order to be able to produce a particularly light club head with good weight distribution, the weight of the composite material preferably accounts for 20-50%, more preferably 20-30%, and most preferably approx. 25% of the total club head weight.

[0026] In order to make the connection between the additional element(s) and the composite material of the shell even stronger, the composite material of the shell may contain an adhesive, particularly in the connection region. In this case, the composite material preferably consists of a fiber-reinforced plastic, which usually forms the base material of the shell, and the adhesive. The adhesive, which is preferably an epoxy resin, is preferably present at least in those areas on the outside of the shell where the shell is connected to the additional element(s). In tests, epoxy resins have been shown to produce particularly strong and durable component connections. The use of an adhesive, in particular an epoxy resin, has proven to be particularly advantageous in terms of the composite material engaging with the local recesses in the laser-structured and / or multi-step surface of the additional element(s). Especially when the recesses are very narrow, the mutual engagement of the materials can still be ensured with the help of the adhesive.

[0027] Due to the formation of the shell from a composite material, the club head can be manufactured with a very low weight, but still be structurally very strong and durable. Due to its low weight, the club head can be made more voluminous and larger in the area of the striking plate, which has a particularly positive effect on the forgiveness of the club head. In addition, the composite material allows the club head to be manufactured in almost any geometric shape.

[0028] The additional element(s) made of a metal are preferably one or more weighting elements, the striking plate and / or a base plate. In particular, if the additional element(s) relate(s) to the striking plate or the base plate, the metal from which they are made may be iron. In particular for the striking plate and / or the base plate, a light metal such as titanium may also be used. The impact plate and / or the base plate may in particular be formed by a sheet metal. Preferably, the impact plate and / or the base plate are attached directly to the outside of the shell and in particular lie directly on it. In the event that the additional element(s) is / are (a) weighting element(s), the metal is preferably tungsten, lead, iron or an alloy thereof.

[0029] If the additional element or elements is / are embedded with its / their respective connection region at least partially in the composite material of the shell, the respective additional element abuts so closely to the composite material that the composite material or a component thereof at least partially engages with the additional element and / or at least partially surrounds it. The additional element and the shell therefore do not merely lie against each other on a purely two-dimensional surface, but there is a certain degree of interlocking between the components or their materials, respectively. The interlocking may also occur only at a microscopic level. Due to the mutual interlocking of the additional element and the shell, the connection between the shell and the respective additional element is generally significantly strengthened. Preferably, the entire connection region is embedded in the composite material of the shell.

[0030] Preferably, the composite material of the shell is molded onto the additional element(s). In this way, a particularly tight and thus firm connection between the components can be achieved.

[0031] Preferably, the plastic of the composite material forming the shell, advantageously a thermosetting plastic, is cast in liquid form under vacuum during manufacture so that it flows into the recesses formed by the multi-stepped and / or laser-structured surface. It then preferably chemically cross-links at a temperature of preferably 70-120° C. for approx. 2-20 minutes. The plastic preferably forms both a form fit and a material bond with the connection region of the respective additional element.

[0032] A laser-structured surface is created by treating a part of the surface material in a targeted manner using a laser, i.e., usually by ablating it. Therein, the surface material can be melted in a controlled manner in specific areas using the laser, so that it then solidifies in a defined structure. In particular, the laser radiation can be applied in a pulsed manner. Laser structuring is recognizable in the finished component due to a reproducible geometry provided in the surface, whereby the recognizability can be achieved by eye or, for example, with the aid of a microscope. The laser-structured surface can form only part of the connection region or the entire connection region. The provision of a laser-structured surface is particularly well suited for bonding the impact plate and / or the base plate to the shell, as these components are usually very thin-walled for material- and weight reduction purposes.

[0033] The laser-structured surface preferably has a regular geometry. For example, the laser-structured surface may comprise a plurality of grooves arranged parallel to each other and at regular intervals. A laser-structured surface with a plurality of intersecting grooves, in particular perpendicularly intersecting grooves, has proven to be particularly effective in terms of a firm connection.

[0034] If the connection region is formed by a multi-stepped surface, the steps on the corresponding additional element are usually easily visible to the naked eye. Preferably, the steps run parallel to each other. It is also preferable for the steps to be arranged at regular intervals. This type of multi-stepped surface with parallel steps arranged at regular intervals has proven to be particularly effective in terms of bonding the additional element to the shell. The multi-stepped surface can form only part of the connection region or the entire connection region. The additional element(s) may be, in particular, cast, pressed, or sintered parts, for the production of which a casting, pressing, or sintering mold with a correspondingly multi-stepped surface is provided. In this case, the production of the multi-stepped surface does not usually require any additional work steps. The provision of a multi-stepped surface is particularly well suited for bonding weighting elements to the shell, especially when the weighting elements are cast, pressed, or sintered parts.

[0035] In addition to embedding the connection region in the composite material, the additional element or elements can also be secured against detachment or slippage, respectively, by means of further measures. For example, if the additional element or elements are arranged in an interior space of the club head, the shell may have projections protruding into the interior space, each of which forms a stop for the additional element(s) to prevent the additional element or elements from slipping relative to the shell.

[0036] In a preferred embodiment, at least some or all of the additional element(s) are one or more weighting elements, each of which is arranged completely inside the shell. Due to their high weight and associated inertia, weighting elements are particularly susceptible to slipping or even detaching from the composite material of the shell. The arrangement completely inside the shell allows the club head to be manufactured in such a way that a particularly efficient force transmission via the shell is achieved. The forces generated during the stroke can then be distributed and transmitted via the shell without any significant influence from the weighting element(s). The arrangement of the weighting elements inside the shell has the additional advantage that the risk of injury is significantly reduced if they do come loose. Advantageously, the shell essentially completely surrounds the weighting element(s). In order to achieve an optimal shape with regard to weight distribution, the weighting element(s) are advantageously cast, pressed, or sintered parts.

[0037] Preferably, a first weighting element and a second weighting element are provided, which, relative to the intended main direction of impact, are arranged on the side of the club head, in particular in each case laterally with respect to the striking plate. In this case, the striking plate can be arranged in particular between the first and the second weighting element. The two weighting elements can be arranged inside or outside the shell.

[0038] The weighting element or elements as a whole preferably each have an irregular geometric shape that is at least partially adapted to the inner surface of the shell. In this way, the weight distribution of the club head can be optimized particularly well.

[0039] In a further preferred embodiment, at least one of the additional elements is a striking plate which is attached to an outer side of the shell and serves to strike a golf ball. In order to improve the weight distribution of the club head, the striking plate is often made of thin-walled sheet metal, which poses a particular challenge in terms of permanent attachment to the shell. By laser structuring the striking plate on its side facing the shell, a firm and permanent connection can be achieved.

[0040] Preferably, essentially all surfaces of the connection regions of the additional element(s) that are at least partially or completely oriented in the intended main striking direction in the projection are formed by a multi-stepped and / or laser-structured surface. This takes into account the fact that the main force acts on the club head along the direction of impact when the ball is struck.

[0041] If the connection region is formed by a multi-stepped surface, the steps of the multi-stepped surface preferably form a surface that is perpendicular to the intended main direction of impact with a deviation of no more than 40°, preferably no more than 20°. By means of such a stepped design, the connection surface facing in the direction of the main direction of impact can be maximized. The forces acting on the club head during the strike are thus distributed over a larger area in the connection region, which has a favorable effect on the strength and durability of the connection.

[0042] In the case of a laser-structured surface, the grooves created by the laser preferably have a greater width in depth than on the surface. In other words, the grooves widen from the surface into the depth of the material. When the composite material of the shell is cast, it can not only enter the grooves and thus engage with them, but also undercut them due to the widening. This allows a particularly strong and durable connection of the components to be achieved.

[0043] As an additional measure to improve the component bond, the connection region can be formed by a roughened surface, whereby the roughening is preferably produced by sandblasting, chemical etching, and / or flat laser treatment. In combination with laser structuring and / or multiple surface gradation, this allows a particularly strong and durable connection of the components to be achieved, which remains stable in the long term even with frequent use of the club head.

[0044] It can be particularly advantageous if the additional element(s) comprise(s) an undercut in relation to the intended main direction of impact, which is preferably provided in an area of the respective additional element on the rear side of the main direction of impact. By engaging the composite material of the shell in these undercuts, the forces occurring during golf play can be absorbed even better, further improving the connection of the respective additional element.

[0045] Preferably, the club head comprises a core made of a gaseous material, in particular air, or a foam material, which is at least partially, preferably completely, surrounded by the shell. A foam material here refers to a substance that is usually manufactured artificially and comprises a low-density, cell-like structure. Materials suitable for foaming and for the present application include, for example, many plastics in the sense of organic, polymeric solids such as thermoplastics, thermosets, or elastomers, which can reduce their volume under pressure, i.e., exhibit compressibility. If the core is made of a gaseous material, such as air in particular, the shell preferably encloses a cavity and the gaseous material filling this cavity forms the core. This gives the core a particularly low weight. Club heads with foamed or gaseous cores have been found to have particularly advantageous hitting characteristics. It is preferable that the core occupies a larger volume of the club head than the shell. However, it is also conceivable that the club head and the shell have a similar volume, which may be the case, for example, with a thin, filigree club head. If there is a weighting element inside the shell, it can be arranged inside or outside the core.

[0046] The invention also relates to a golf club with a club head as described above. The golf club may also have a hosel, a golf club shaft, and a golf club grip.

[0047] Furthermore, the invention relates to a method for manufacturing a club head, which is preferably designed in accordance with the above specifications, wherein the method comprises at least the step of embedding one or more additional elements made of metal, each with a connection region, at least partially in a composite material, in particular a fiber-reinforced plastic, an outer shell of the club head. The method also comprises the step of laser structuring and / or multiple stepping the connection region of the additional element(s) before embedding it in the composite material. Laser structuring is usually performed using a pulsed or non-pulsed laser. Multiple stepping is preferably produced by a casting process.BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Preferred embodiments of the invention are described in the following with reference to the drawings, which are only for the purpose of illustrating the present preferred embodiments of the invention and not for the purpose of limiting the same. In the drawings,

[0049] FIG. 1 shows a perspective view of a partially transparent club head according to the invention in the form of a driver;

[0050] FIG. 2 a perspective view of a partially transparent club head according to the invention in the form of a fairway wood;

[0051] FIG. 3 a perspective view of a partially transparent club head according to the invention in the form of a 7-iron;

[0052] FIG. 4 a perspective view of a partially transparent club head according to the invention in the form of a 9-iron;

[0053] FIG. 5 a perspective view of a partially transparent club head according to the invention in the form of a pitching wedge;

[0054] FIG. 6 a perspective view of a partially transparent club head according to the invention in the form of a sand wedge;

[0055] FIG. 7 a perspective view of a partially transparent club head according to the invention in the form of a putter;

[0056] FIG. 8a a perspective exterior view of the club head of FIG. 1;

[0057] FIG. 8b a perspective view of the weighting elements, the striking plate, and the base plate of the club head of FIG. 8a;

[0058] FIG. 8c a perspective view of the weighting elements of the club head of FIG. 8a;

[0059] FIG. 9a a perspective exterior view of the club head of FIG. 4;

[0060] FIG. 9b a perspective view of the weighting elements, the striking plate, and the base plate of the club head of FIG. 9a;

[0061] FIG. 9c a perspective view of the weighting elements of the club head of FIG. 9a;

[0062] FIG. 10a a perspective exterior view of the club head of FIG. 5;

[0063] FIG. 10b a perspective view of the weighting elements of the club head of FIG. 10a;

[0064] FIG. 10c a sectional view in plane A-A of the club head of FIG. 10a;

[0065] FIG. 11 a top view of the laser-structured rear side of the striking plate of a club head according to the invention;

[0066] FIG. 12 a microscopic image of the laser-structured connection region of the striking plate of a club head according to the invention in the cross-sectional view;

[0067] FIG. 13 a microscopic image of the laser-structured connection region of the striking plate of another club head according to the invention in the cross-sectional view;

[0068] FIG. 14 a microscopic image of the laser-structured connection region of the striking plate of the club head of FIG. 13 in the top view;

[0069] FIG. 15 a schematic cross-sectional view of a laser-structured surface of a club head according to the invention in the cross-sectional view;

[0070] FIG. 16a a microscopic image of the laser-structured connection region of the striking plate of another club head according to the invention in the cross-sectional view;

[0071] FIG. 16b a schematic representation of the contour line of the image of FIG. 16a;

[0072] FIG. 17a a microscopic image of the laser-structured connection region of the striking plate of yet another club head according to the invention in the cross-sectional view;

[0073] FIG. 17b a schematic representation of the contour line of the image of FIG. 17a;

[0074] FIG. 18 a schematic representation of a first, preferred variant of a laser-structured connection region of a club head according to the invention in the top view;

[0075] FIG. 19 a schematic representation of a second variant of a laser-structured connection region of a club head according to the invention in the top view;

[0076] FIG. 20 a schematic representation of a third variant of a laser-structured connection region of a club head according to the invention, in the top view;

[0077] FIG. 21 a schematic representation of a fourth variant of a laser-structured connection region of a club head according to the invention, in the top view;

[0078] FIG. 22 a schematic cross-sectional partial view of a club head according to the invention; and

[0079] FIG. 23 an enlarged perspective partial view into the interior of the club head of FIG. 7.DESCRIPTION OF PREFERRED EMBODIMENTS

[0080] FIGS. 1 to 22 show various preferred embodiments of golf club heads 1 according to the invention and parts thereof. Elements that perform the same or a similar function are designated by the same reference numeral, regardless of whether they belong to the same or different embodiments.

[0081] FIGS. 1 to 7 show various types of club heads 1 according to the invention, which together form a complete set of golf club heads. In order to make the inner workings of the club heads 1 visible, they are drawn in a partially transparent manner for illustrative purposes.

[0082] Regardless of the type of club head 1, each has a shell 3 made of a composite material, which forms a large part of the outer surface of the club head 1 and surrounds an interior space of the club head 1. The shell 3 thus forms a base body of the club head 1, which absorbs and transmits the main forces occurring during golf play and forms the main structure of the club head 1. The interior space forms a core made of a gaseous material, in particular air. The club head 1 is thus hollow, with the shell 3 forming a hollow body. The design of the shell 3 as a hollow body with an interior filled with gas, in particular air, results in a particularly light club head with good hitting characteristics.

[0083] The composite material of the shell 3 is preferably a fiber-reinforced plastic material, in particular a carbon fiber-reinforced plastic material. Polyetheretherketone (PEEK) or epoxy resin (EP) is preferably used as the plastic material.

[0084] The club head 1 in each case has a hosel 2, which is used to attach the club head 1 to a club shaft not shown in the figures. The club shaft can be inserted into the hosel 2 and thus into the club head 1 for this purpose.

[0085] A striking plate 6 is attached to the front of the shell 3 in all club types shown in FIGS. 1 to 7. The striking plate 6, which forms an additional element preferably made of a thin-walled metal sheet, preferably of iron, steel, stainless steel, or a light metal such as titanium, may have grooves on its front side to improve the striking properties, as can be seen in FIGS. 1 to 7. The rear side of the striking plate 6, which is not visible in FIGS. 1 to 7 but is shown in FIG. 11, has a laser-structured surface 10 for attachment to the shell 3. The laser-structured surface 10 forms a connection region 61 of the striking plate 6, with which the striking plate 6 rests against the outside of the shell 3.

[0086] In the interior space of the club head 1, which is surrounded by the shell 3 and bounded on the outside, two weighting elements 7 are arranged in each of the types shown in FIGS. 1 to 7. The weighting elements 7 form additional elements and are preferably made of a metal such as tungsten, lead, brass, iron, or an alloy thereof. The weighting elements 7 typically have a single weight of 20 g or higher. The total weight of all weighting elements 7 provided in a club head 1 is preferably 60 g or higher, and even more preferably 100 g or higher. In the embodiments shown here, the weighting elements 7 are each arranged laterally on the club head 1. It has been found that with this arrangement of the weighting elements 7 a particularly good weight distribution can be achieved, while also providing good force transmission within the shell 3.

[0087] The weighting elements 7 are each cast, pressed, or sintered parts which, as a whole, have an irregular geometric shape that is at least partially adapted to the inner surface of the shell 3. The weight distribution achieved by the weighting elements 7 is thus optimally adapted to the shape of the respective racket type.

[0088] The weighting elements 7 each have a connection region 71 with a multi-stepped surface 11, which is clearly visible, for example, in FIGS. 9c and 10b. The weighting elements 7 are each attached to the inner surface of the shell 3 via the connection region 71.

[0089] FIGS. 8a to 8c, 9a to 9c, and 10a and 10b each show an enlarged external view of an exemplary club head type and parts thereof.

[0090] FIGS. 8a and 9a, in conjunction with FIGS. 8b and 9b, show that a base plate 8 is attached to the underside of the club head 1. The base plate 8 resting on the outside of the shell 3 serves to reinforce the club head 1 on its underside, which is usually particularly exposed during golf play and is therefore susceptible to damage. The base plate 8 forms an additional element of the club head 1, and preferably is made of thin-walled sheet metal. It comprises a connection region 81 with a laser-structured surface, which serves to permanently attach the base plate 8 to the shell 3.

[0091] The above-mentioned additional elements, each made of metal, in the form of the striking plate 6, the weighting elements 7, and the base plate 8 are embedded with their connection region 61, 71, and 81, respectively, in the composite material of the shell 3. There is therefore a certain degree of engagement between the shell 3 and the respective additional element 6, 7 or 8. For this purpose, during the manufacture of the club head 1, the composite material of the shell 3 is cast onto the respective additional element 6, 7 or 8. The additional elements 6, 7, 8 are thus cast in a material bonded manner with the composite material of the shell 3. In an alternative manufacturing method, it would also be conceivable to spray the composite material of the shell 3 onto the additional elements 6, 7, 8.

[0092] To make the connection even stronger, the composite material of the shell 3 can comprise an adhesive in the connection regions 61, 71, and 81. The base material of the shell 3 is then coated with an adhesive in the corresponding areas, whereby the adhesive can be regarded as a component of the composite material. The metal parts or additional elements 6, 7, 8, respectively, are then bonded to the shell 3 over a large area. This bonding is particularly advantageous when carried out in situ with low-viscosity, reactive epoxy resins, and is especially advantageous when additionally carried out under vacuum and at elevated temperatures so that the adhesive can optimally wet the surface at low viscosity (preferably between 50-10′000 mPas, in particular 100-500 mPas).

[0093] Due to the laser structuring and / or the multiple steps in the connection region, the surface area relevant for bonding the additional elements 6, 7, 8 is significantly increased. When the composite material is poured, it penetrates the local recesses formed by the steps or laser structuring, so that the additional elements 6, 7, 8 are embedded in the material of the shell 3, creating a particularly tight and strong bond between the components. This significantly increases the strength of the connection between the additional elements 6, 7, 8 and the shell 3, considerably reducing the risk of the additional elements 6, 7, 8 slipping or even detaching from the shell 3.

[0094] Preferably, the connection regions 61, 71, and 81 of the impact plate 6, the weighting elements 7, and the base plate 8 are also roughened. This allows the materials of the additional elements 6, 7, 8 and the shell 3 to interlock even better, thereby making the connection even stronger. The roughening of the surfaces of the respective connection regions 61, 71 and 81 is preferably produced by means of sandblasting, chemical etching and / or flat laser treatment.

[0095] In the cross-sectional view of FIG. 10c, the steps of the multi-stepped surfaces 11 of the connection regions 71 of one of the weighting elements 7 are clearly visible. The steps of the stepped surface 11 provided on the front side of the weighting element 7 each form a surface that is perpendicular to the intended main striking direction H with a deviation of at most 40°, preferably at most 20°. In the embodiment shown in FIG. 10c, the angle α of deviation at which the steps of the stepped surface 11 with their respective surfaces are perpendicular to the intended main striking direction H is approximately 14°. In this way, the forces acting on the club head 1 during impact can be absorbed particularly well in the connection region 71. Tests have shown that the connection of the weighting elements 7 can be further improved by aligning the steps in such a way that they each form a surface perpendicular to the intended main striking direction H. In practice, very good results have already been achieved with a step configuration in which the respective step surfaces are perpendicular to the intended main strike direction H with a maximum deviation of 40°, preferably a maximum of 20°.

[0096] Preferably, all surfaces of the connection regions of the weighting elements 7 facing the intended main striking direction in the projection form a multi-stepped and / or laser-structured surface, whereby the steps of all these surfaces are advantageously aligned in such a way that they each have a surface perpendicular to the intended main striking direction H, with a deviation of at most 40°, preferably a maximum deviation of 20°.

[0097] This further reduced slippage or even detachment of the weighting elements 7 in long-term tests.

[0098] In the rear region, i.e., on the outer surfaces of the respective weighting element 7 that are at least partially oriented in the projection against the intended main striking direction H, the multi-stepped surface 11 preferably forms undercuts relative to the main striking direction H. Such undercuts are provided, for example, in the weighting elements 7 shown in FIG. 9c in the areas marked with the dashed arrows. The strength of the connection of the weighting elements 7 can thus be improved, particularly with regard to the main forces occurring during striking.

[0099] The laser-structured surface 10 of the connection region 61 of the striking plate 6, which can be seen in FIG. 11, comprises a regular geometry with a plurality of parallel grooves that intersect perpendicularly and are arranged at regular intervals. With such a pattern, a particularly strong connection of the striking plate 6 to the shell 3 could be achieved. Due to the regular pattern, the laser structuring of the connection region 61 is also easily recognizable to the naked eye. The distances between the parallel grooves are preferably in the range between 0.1 mm and 0.3 mm, in particular at approximately 0.2 mm, which has proven to be a good compromise between the strength of the connection on the one hand and the amount of work and thermal distortion of the plate during energy input on the other.

[0100] FIG. 11 shows a microscopic image of the connection region between an impact plate 6 with a laser-structured surface 10 and the composite material of a shell 3. The grooves of the laser-structured surface 10, arranged at regular intervals, and the interlocking of the materials of the two components are clearly visible. The components 6 and 3 are thus connected to each other in a form-fitting and material-bonded manner.

[0101] A microscopic image of the connection region between the striking plate 6 and the shell 3 of another club head 1, also according to the invention, is shown in FIG. 13. Here, the laser-structured surface 10 comprises an additional structure with small local elevations and depressions in the intermediate areas 13 arranged between the grooves. The additional structure of the intermediate areas 13 can be achieved by welded metal spatter. The same laser-structured surface 10 is shown in FIG. 10 in the top view. FIG. 15 schematically shows a corresponding contour image. The additional structuring in the intermediate areas 13 further increases the total surface area of the connection region, thereby strengthening the connection between the components.

[0102] FIG. 15 shows that the grooves formed by the laser-structured surface 10 widen in a downward direction in some cases and / or form undercuts 12. By using suitable parameter settings for the preferably pulsed laser input of the grooves, it is possible to easily achieve a widening of the grooves in a downward direction and to provoke the formation of undercuts. Undercuts 12 are also formed by the local elevations in the intermediate surfaces 13. The material of the impact plate 6 can thus be gripped by the composite material of the shell 3, thereby creating a particularly strong bond.

[0103] In terms of manufacturability and effect, the grooves of the laser-structured surface 10 preferably have a width in a range between 30 and 100 μm, in particular between 30 and 50 μm. The depth of the grooves is preferably in at range between 20 and 100 μm, in particular between 30 and 100 μm. Grooves with a width of less than 30 μm, for example in a range between 15 and 30 μm, and / or with a depth of less than 20 μm, for example in a range between 10 and 20 μm, could prove advantageous in the future and depending on their manufacturability using a laser.

[0104] FIG. 16a shows a microscopic image of the laser-structured surface 10 of the striking plate 6 of another club head according to the invention in the cross-sectional view. FIG. 16b shows the contour line in the region of the interfaces for better visibility. Here, too, it is clearly visible how the composite material of the shell 3 engages with the grooves of the laser-structured surface 10 and even undercuts them in the areas of the undercuts 12. Mutual engagement also takes place in the areas of the intermediate surfaces 13, where undercuts 12 are also engaged.

[0105] Another variant of a laser-structured surface 10 with undercuts 12 is shown as a microscopic image in FIG. 17a and as a traced contour line in FIG. 17b. Compared to the embodiment shown in FIGS. 16a and 16b, the structuring of the intermediate surfaces 13 is considerably more pronounced here, i.e., it is of a similar magnitude to the grooves arranged between them.

[0106] FIGS. 18 to 21 show various possible geometric designs of the laser-structured surface 10. FIG. 18 shows the aforementioned preferred arrangement of perpendicularly intersecting grooves. FIGS. 19 and 20 show a laser-structured surface 10 with cross-shaped depressions or elevations in a parallel or staggered arrangement. In the embodiment shown in FIG. 21, the laser-structured surface 10 has circular depressions or elevations. All of the laser-structured surfaces 10 shown in the variants of FIGS. 18 to 21 have a regular geometry with local elevations or depressions, respectively, arranged at uniform intervals.

[0107] In order not to negatively influence the positive properties of the composite material of the shell 3 with regard to elasticity and natural frequencies, the impact plate 6 and the base plate 8 are each designed to be as thin as possible. Preferred thicknesses of the impact plate 6 are in a range of 0.2-0.8 mm, in particular approximately 0.5 mm. Preferred thicknesses of the base plate 8 are in a range of 0.8-1.25 mm.

[0108] FIG. 22 shows that the impact plate 6 preferably has an edge phase 14, i.e., the edge of the impact plate 6 is chamfered. The sheet thickness is preferably tapered by 30-50% toward the edge. Typically, the edge phase 14 is 1-4 mm wide. The grooves of the laser-structured surface 10, however, are advantageously present up to the outer edge. The edge area of the impact plate 6, in particular the edge phase 14, can also be more densely laser-structured in order to further strengthen the bond in this area.

[0109] A further measure, which is preferably used in addition to the laser-structured and / or multi-stepped and optionally roughened surfaces to prevent the weighting element 7 from slipping or detaching, respectively, can be seen in FIG. 23: The shell 3 has a plurality of inwardly projecting protrusions 15, each of which rests against an edge on an outer side of the weighting element 7, thereby restricting its mobility. FIG. 23 also clearly shows the core 4 of the club head 1, which is essentially completely surrounded by the shell 3 and is formed from a gaseous material, such as air in particular. The shell 3 thus forms a hollow body.LIST OF REFERENCE SIGNS1 Club head

[0111] 2 Hosel

[0112] 3 Shell

[0113] 4 Core

[0114] 6 Impact plate

[0115] 61 Connection region

[0116] 7 Weighting element

[0117] 71 Connection region

[0118] 8 Base plate

[0119] 81 Connection region

[0120] 10 Laser-structured surface

[0121] 11 Stepped surface

[0122] 12 Undercut

[0123] 13 Intermediate surface

[0124] 14 Edge phase

[0125] 15 Protrusion

[0126] H Main striking direction

[0127] α Angle

Examples

Embodiment Construction

[0080]FIGS. 1 to 22 show various preferred embodiments of golf club heads 1 according to the invention and parts thereof. Elements that perform the same or a similar function are designated by the same reference numeral, regardless of whether they belong to the same or different embodiments.

[0081]FIGS. 1 to 7 show various types of club heads 1 according to the invention, which together form a complete set of golf club heads. In order to make the inner workings of the club heads 1 visible, they are drawn in a partially transparent manner for illustrative purposes.

[0082]Regardless of the type of club head 1, each has a shell 3 made of a composite material, which forms a large part of the outer surface of the club head 1 and surrounds an interior space of the club head 1. The shell 3 thus forms a base body of the club head 1, which absorbs and transmits the main forces occurring during golf play and forms the main structure of the club head 1. The interior space forms a core made of a ...

TECHNICAL FIELD

[0001] The present invention relates to a club head for a golf club and a golf club with such a club head. The invention also relates to a method for manufacturing such a club head.PRIOR ART

[0002] Golf is a widely practiced sport in which both the golfer's performance and the technological characteristics of the golf club are of central importance. From a technological perspective, it is important that the golf ball can be hit as accurately and precisely as possible toward the hole from a wide variety of situations. In the field of golf club development and design, one of the goals is therefore to improve both the accuracy of direction and the achievable distance of the shots. Another important factor in the development of golf clubs is the forgiveness of the golf club, and in particular the club head, i.e., the ability of the device to achieve sufficient directional accuracy or a good distance, respectively, even with a less than optimal shot.

[0003] In order to achieve optimal weight distribution in the club head with regard to the above-mentioned requirements and to positively influence the dynamics of the swing, weighting elements are often provided on or in the club head of golf clubs.

[0004] For example, document US 2015 / 0045130 A1 discloses a club head with weighting elements arranged on the outside of the club head and inside a damping element provided inside.

[0005] Document U.S. Pat. No. 9,333,390 B1 discloses a golf club head in which weighting elements can be inserted.

[0006] Document U.S. Pat. No. 10,213,665 B1 discloses hollow golf club heads with a recess on the underside for inserting disc-shaped weighting elements.

[0007] Furthermore, document US 2013 / 0085012 A1 discloses a golf club head with a hollow structure filled with a foam material and a metal striking plate attached to the outside.

[0008] Composite materials consisting of fiber-reinforced plastic material have been increasingly used in the manufacture of golf club heads for some time now. The advantage of such materials over conventionally used metals lies in particular in their weight. Composite materials can be used to manufacture golf club heads whose structure is many times lighter than that of conventional metal club heads. With the aid of weighting elements, a desired weight distribution can be adjusted even more precisely. By aligning the fibers appropriately, the force transmission and transfer within the club head can also be controlled and optimized with composite materials. Furthermore, composite materials can be used to form club heads with a wide variety of geometries. In club heads made of composite materials, the striking plate is usually formed from a metal plate.

[0009] For example, document U.S. Pat. No. 5,193,811 A discloses a golf club head with a body made of a fiber-reinforced material and a metal plate attached to it. Inside the body is a core made of a foam material and, in some embodiments, a weighting element.

[0010] Document U.S. Pat. No. 5,547,427 A discloses a golf club head with a hollow body that can be made of a fiber-reinforced thermoplastic material and filled with a foam material. At the front, the interior space formed by the hollow body is closed off with a striking plate. At the rear, the hollow body has a recess into which a weighting element is inserted.

[0011] Furthermore, document US 2023 / 0056990 A1 discloses a golf club head with a base body made of metal. The shell-like base body comprises an opening into which a part made of a fiber-reinforced plastic material is inserted.

[0012] One challenge with club heads whose base body is made of a fiber-reinforced plastic material is the connection of the additional metal elements, such as the weighting elements or the striking plate, to the composite material. Golf usually involves very high forces, as the golf ball is often struck by the club head with great force. When the golf ball is struck, which according to the rules takes place within a maximum of 239 microseconds, the ball is accelerated with up to 30,000 g. The golf club is decelerated by 2,000 to over 5,000 g. This places a very high strain on the connection between the weighting elements and the composite material that forms the club head structure. The high main load of the deceleration during the swing is superimposed by lateral accelerations, which occur in all directions as soon as the ball is hit outside the center of gravity of the club head, as well as further impact stresses upon contact with the ground. In addition, the connection is compromised by the strong vibrations of the structure after the impact and is subject to thermally superimposed stresses due to the different thermal expansions of the connection partners. The additional elements attached to or inside the golf club can thus detach from the composite material over time. The resulting gradual or sudden movement of the additional elements relative to the base body can lead to undesirable changes in the striking behavior, which can ultimately render the club head unusable. Additional elements that detach completely from the club head can also pose a hazard to the player.SUMMARY OF THE INVENTION

[0013] It is an object of the invention to provide a club head for a golf club made of a composite material, wherein one or more additional parts are held securely to the composite material for a long time.

[0014] This problem is solved by a club head comprising the features of claim 1. Claim 15 specifies a golf club with such a club head, and claim 16 specifies a method for manufacturing a club head. Further embodiments are specified in the dependent claims.

[0015] A club head for a golf club is therefore specified, comprising

[0016] an outer shell made of a composite material, in particular a fiber-reinforced plastic; and

[0017] one or more additional elements made of metal, each of which is at least partially embedded in the composite material of the shell with a connection region.

[0018] The connection region of the one or more additional elements is formed in each case by a laser-structured and / or multi-stepped surface.

[0019] By forming the connection region of the additional element(s) with a laser-structured and / or multi-stepped surface, the metal can bond particularly efficiently and permanently with the composite material of the shell. The laser structuring and / or the steps increase the total surface area of the connection region, whereby a stronger connection of the respective additional element to the shell is achieved. In particular, a matrix material of the shell can engage with the structure provided in the surface of the connection region and, if necessary, even engage behind and / or underneath it, resulting in a particularly strong connection between the shell and the additional element. In addition, the formation of the laser structuring and / or the steps can be adapted with regard to the forces usually acting on the club head in such a way that the detachment forces acting between the additional element and the shell, such as in particular shear, gravity, and tensile forces, are reduced. For this purpose, the steps can, for example, form undercuts in relation to the intended main direction of impact or form a surface perpendicular to the main direction of impact with a deviation of a maximum of 40°, preferably a maximum of 20°, in order to optimally absorb the forces usually acting on the connection region. The surface structures formed by laser structuring can also be geometrically adapted to the forces that typically occur in such a way that the forces are transferred as efficiently as possible and with minimal separation forces from the respective additional element to the shell and vice versa. It has been found that, for these reasons in particular, the laser-structured and / or multi-stepped surface can sustainably improve the connection of the additional element(s) to the shell with regard to frequent use. Thanks to the laser structuring or the multi-stepped surface, respectively, the number of detachments of additional elements from the shell could be significantly reduced in long-term tests.

[0020] The shell usually forms a base of the club head. The base of the club head refers to the component which absorbs and transfers the forces that are exerted on the club head usually by the golf club shaft or the so-called hosel onto the striking plate or in the opposite direction, and usually forms the main structure of the club head. The striking plate is usually attached to an outer side of the base body, which generally has an opening for inserting or attaching the club shaft or hosel, respectively. The base body also often forms the main shaping element of the club head.

[0021] The shell is understood to be a component that at least partially surrounds an interior space of the club head, i.e., it usually forms at least a part of an outer shell of the club head. In most cases, the shell comprises a certain curvature. Alternatively or additionally, the shell may also comprise corners and / or edges. Preferably, the shell forms a hollow body.

[0022] Advantageously, the shell covers at least 25%, even more advantageously at least 50%, and most advantageously at least 75% of the outer surface of the interior. It has been shown that the forces occurring during golf can be distributed and transmitted particularly advantageously via the club head if the shell covers such a large proportion of the outer surface of the interior. It is even more preferable for the shell to essentially completely enclose the interior of the club head, which means that, for example, there may be a relatively small opening for attaching the club shaft or hosel, but otherwise the interior is completely surrounded by the shell. This can achieve a flow of forces across the club head that is particularly beneficial for golf.

[0023] The club head usually forms the golf club together with the hosel, the golf club shaft, and the golf club grip. The hosel is the connecting piece at the top of the club head into which the shaft is inserted. The hosel can be designed as a separate component from the club head or can be formed by the club head itself.

[0024] The composite material of the shell can be, in particular, a fiber-reinforced plastic, whereby the plastic can be a thermoplastic, but preferably a thermosetting plastic, i.e., a duromer plastic. A composite material is understood here to be a bonded material consisting of two or more materials bonded together. The composite material generally has different properties than each of the individual materials. A composite material usually consists of a base material, referred to as a matrix, and a reinforcing material, such as for example a fiber. Preferred materials for a matrix material are thermoplastic materials such as polyether ether ketone (PEEK), thermosetting materials such as resins, etc. Examples of fibers include materials such as carbon fibers, glass fibers, aramid, Kevlar fibers, etc. The person skilled in the art is aware of a large number of suitable composite materials for the shell.

[0025] In order to be able to produce a particularly light club head with good weight distribution, the weight of the composite material preferably accounts for 20-50%, more preferably 20-30%, and most preferably approx. 25% of the total club head weight.

[0026] In order to make the connection between the additional element(s) and the composite material of the shell even stronger, the composite material of the shell may contain an adhesive, particularly in the connection region. In this case, the composite material preferably consists of a fiber-reinforced plastic, which usually forms the base material of the shell, and the adhesive. The adhesive, which is preferably an epoxy resin, is preferably present at least in those areas on the outside of the shell where the shell is connected to the additional element(s). In tests, epoxy resins have been shown to produce particularly strong and durable component connections. The use of an adhesive, in particular an epoxy resin, has proven to be particularly advantageous in terms of the composite material engaging with the local recesses in the laser-structured and / or multi-step surface of the additional element(s). Especially when the recesses are very narrow, the mutual engagement of the materials can still be ensured with the help of the adhesive.

[0027] Due to the formation of the shell from a composite material, the club head can be manufactured with a very low weight, but still be structurally very strong and durable. Due to its low weight, the club head can be made more voluminous and larger in the area of the striking plate, which has a particularly positive effect on the forgiveness of the club head. In addition, the composite material allows the club head to be manufactured in almost any geometric shape.

[0028] The additional element(s) made of a metal are preferably one or more weighting elements, the striking plate and / or a base plate. In particular, if the additional element(s) relate(s) to the striking plate or the base plate, the metal from which they are made may be iron. In particular for the striking plate and / or the base plate, a light metal such as titanium may also be used. The impact plate and / or the base plate may in particular be formed by a sheet metal. Preferably, the impact plate and / or the base plate are attached directly to the outside of the shell and in particular lie directly on it. In the event that the additional element(s) is / are (a) weighting element(s), the metal is preferably tungsten, lead, iron or an alloy thereof.

[0029] If the additional element or elements is / are embedded with its / their respective connection region at least partially in the composite material of the shell, the respective additional element abuts so closely to the composite material that the composite material or a component thereof at least partially engages with the additional element and / or at least partially surrounds it. The additional element and the shell therefore do not merely lie against each other on a purely two-dimensional surface, but there is a certain degree of interlocking between the components or their materials, respectively. The interlocking may also occur only at a microscopic level. Due to the mutual interlocking of the additional element and the shell, the connection between the shell and the respective additional element is generally significantly strengthened. Preferably, the entire connection region is embedded in the composite material of the shell.

[0030] Preferably, the composite material of the shell is molded onto the additional element(s). In this way, a particularly tight and thus firm connection between the components can be achieved.

[0031] Preferably, the plastic of the composite material forming the shell, advantageously a thermosetting plastic, is cast in liquid form under vacuum during manufacture so that it flows into the recesses formed by the multi-stepped and / or laser-structured surface. It then preferably chemically cross-links at a temperature of preferably 70-120° C. for approx. 2-20 minutes. The plastic preferably forms both a form fit and a material bond with the connection region of the respective additional element.

[0032] A laser-structured surface is created by treating a part of the surface material in a targeted manner using a laser, i.e., usually by ablating it. Therein, the surface material can be melted in a controlled manner in specific areas using the laser, so that it then solidifies in a defined structure. In particular, the laser radiation can be applied in a pulsed manner. Laser structuring is recognizable in the finished component due to a reproducible geometry provided in the surface, whereby the recognizability can be achieved by eye or, for example, with the aid of a microscope. The laser-structured surface can form only part of the connection region or the entire connection region. The provision of a laser-structured surface is particularly well suited for bonding the impact plate and / or the base plate to the shell, as these components are usually very thin-walled for material- and weight reduction purposes.

[0033] The laser-structured surface preferably has a regular geometry. For example, the laser-structured surface may comprise a plurality of grooves arranged parallel to each other and at regular intervals. A laser-structured surface with a plurality of intersecting grooves, in particular perpendicularly intersecting grooves, has proven to be particularly effective in terms of a firm connection.

[0034] If the connection region is formed by a multi-stepped surface, the steps on the corresponding additional element are usually easily visible to the naked eye. Preferably, the steps run parallel to each other. It is also preferable for the steps to be arranged at regular intervals. This type of multi-stepped surface with parallel steps arranged at regular intervals has proven to be particularly effective in terms of bonding the additional element to the shell. The multi-stepped surface can form only part of the connection region or the entire connection region. The additional element(s) may be, in particular, cast, pressed, or sintered parts, for the production of which a casting, pressing, or sintering mold with a correspondingly multi-stepped surface is provided. In this case, the production of the multi-stepped surface does not usually require any additional work steps. The provision of a multi-stepped surface is particularly well suited for bonding weighting elements to the shell, especially when the weighting elements are cast, pressed, or sintered parts.

[0035] In addition to embedding the connection region in the composite material, the additional element or elements can also be secured against detachment or slippage, respectively, by means of further measures. For example, if the additional element or elements are arranged in an interior space of the club head, the shell may have projections protruding into the interior space, each of which forms a stop for the additional element(s) to prevent the additional element or elements from slipping relative to the shell.

[0036] In a preferred embodiment, at least some or all of the additional element(s) are one or more weighting elements, each of which is arranged completely inside the shell. Due to their high weight and associated inertia, weighting elements are particularly susceptible to slipping or even detaching from the composite material of the shell. The arrangement completely inside the shell allows the club head to be manufactured in such a way that a particularly efficient force transmission via the shell is achieved. The forces generated during the stroke can then be distributed and transmitted via the shell without any significant influence from the weighting element(s). The arrangement of the weighting elements inside the shell has the additional advantage that the risk of injury is significantly reduced if they do come loose. Advantageously, the shell essentially completely surrounds the weighting element(s). In order to achieve an optimal shape with regard to weight distribution, the weighting element(s) are advantageously cast, pressed, or sintered parts.

[0037] Preferably, a first weighting element and a second weighting element are provided, which, relative to the intended main direction of impact, are arranged on the side of the club head, in particular in each case laterally with respect to the striking plate. In this case, the striking plate can be arranged in particular between the first and the second weighting element. The two weighting elements can be arranged inside or outside the shell.

[0038] The weighting element or elements as a whole preferably each have an irregular geometric shape that is at least partially adapted to the inner surface of the shell. In this way, the weight distribution of the club head can be optimized particularly well.

[0039] In a further preferred embodiment, at least one of the additional elements is a striking plate which is attached to an outer side of the shell and serves to strike a golf ball. In order to improve the weight distribution of the club head, the striking plate is often made of thin-walled sheet metal, which poses a particular challenge in terms of permanent attachment to the shell. By laser structuring the striking plate on its side facing the shell, a firm and permanent connection can be achieved.

[0040] Preferably, essentially all surfaces of the connection regions of the additional element(s) that are at least partially or completely oriented in the intended main striking direction in the projection are formed by a multi-stepped and / or laser-structured surface. This takes into account the fact that the main force acts on the club head along the direction of impact when the ball is struck.

[0041] If the connection region is formed by a multi-stepped surface, the steps of the multi-stepped surface preferably form a surface that is perpendicular to the intended main direction of impact with a deviation of no more than 40°, preferably no more than 20°. By means of such a stepped design, the connection surface facing in the direction of the main direction of impact can be maximized. The forces acting on the club head during the strike are thus distributed over a larger area in the connection region, which has a favorable effect on the strength and durability of the connection.

[0042] In the case of a laser-structured surface, the grooves created by the laser preferably have a greater width in depth than on the surface. In other words, the grooves widen from the surface into the depth of the material. When the composite material of the shell is cast, it can not only enter the grooves and thus engage with them, but also undercut them due to the widening. This allows a particularly strong and durable connection of the components to be achieved.

[0043] As an additional measure to improve the component bond, the connection region can be formed by a roughened surface, whereby the roughening is preferably produced by sandblasting, chemical etching, and / or flat laser treatment. In combination with laser structuring and / or multiple surface gradation, this allows a particularly strong and durable connection of the components to be achieved, which remains stable in the long term even with frequent use of the club head.

[0044] It can be particularly advantageous if the additional element(s) comprise(s) an undercut in relation to the intended main direction of impact, which is preferably provided in an area of the respective additional element on the rear side of the main direction of impact. By engaging the composite material of the shell in these undercuts, the forces occurring during golf play can be absorbed even better, further improving the connection of the respective additional element.

[0045] Preferably, the club head comprises a core made of a gaseous material, in particular air, or a foam material, which is at least partially, preferably completely, surrounded by the shell. A foam material here refers to a substance that is usually manufactured artificially and comprises a low-density, cell-like structure. Materials suitable for foaming and for the present application include, for example, many plastics in the sense of organic, polymeric solids such as thermoplastics, thermosets, or elastomers, which can reduce their volume under pressure, i.e., exhibit compressibility. If the core is made of a gaseous material, such as air in particular, the shell preferably encloses a cavity and the gaseous material filling this cavity forms the core. This gives the core a particularly low weight. Club heads with foamed or gaseous cores have been found to have particularly advantageous hitting characteristics. It is preferable that the core occupies a larger volume of the club head than the shell. However, it is also conceivable that the club head and the shell have a similar volume, which may be the case, for example, with a thin, filigree club head. If there is a weighting element inside the shell, it can be arranged inside or outside the core.

[0046] The invention also relates to a golf club with a club head as described above. The golf club may also have a hosel, a golf club shaft, and a golf club grip.

[0047] Furthermore, the invention relates to a method for manufacturing a club head, which is preferably designed in accordance with the above specifications, wherein the method comprises at least the step of embedding one or more additional elements made of metal, each with a connection region, at least partially in a composite material, in particular a fiber-reinforced plastic, an outer shell of the club head. The method also comprises the step of laser structuring and / or multiple stepping the connection region of the additional element(s) before embedding it in the composite material. Laser structuring is usually performed using a pulsed or non-pulsed laser. Multiple stepping is preferably produced by a casting process.BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Preferred embodiments of the invention are described in the following with reference to the drawings, which are only for the purpose of illustrating the present preferred embodiments of the invention and not for the purpose of limiting the same. In the drawings,

[0049] FIG. 1 shows a perspective view of a partially transparent club head according to the invention in the form of a driver;

[0050] FIG. 2 a perspective view of a partially transparent club head according to the invention in the form of a fairway wood;

[0051] FIG. 3 a perspective view of a partially transparent club head according to the invention in the form of a 7-iron;

[0052] FIG. 4 a perspective view of a partially transparent club head according to the invention in the form of a 9-iron;

[0053] FIG. 5 a perspective view of a partially transparent club head according to the invention in the form of a pitching wedge;

[0054] FIG. 6 a perspective view of a partially transparent club head according to the invention in the form of a sand wedge;

[0055] FIG. 7 a perspective view of a partially transparent club head according to the invention in the form of a putter;

[0056] FIG. 8a a perspective exterior view of the club head of FIG. 1;

[0057] FIG. 8b a perspective view of the weighting elements, the striking plate, and the base plate of the club head of FIG. 8a;

[0058] FIG. 8c a perspective view of the weighting elements of the club head of FIG. 8a;

[0059] FIG. 9a a perspective exterior view of the club head of FIG. 4;

[0060] FIG. 9b a perspective view of the weighting elements, the striking plate, and the base plate of the club head of FIG. 9a;

[0061] FIG. 9c a perspective view of the weighting elements of the club head of FIG. 9a;

[0062] FIG. 10a a perspective exterior view of the club head of FIG. 5;

[0063] FIG. 10b a perspective view of the weighting elements of the club head of FIG. 10a;

[0064] FIG. 10c a sectional view in plane A-A of the club head of FIG. 10a;

[0065] FIG. 11 a top view of the laser-structured rear side of the striking plate of a club head according to the invention;

[0066] FIG. 12 a microscopic image of the laser-structured connection region of the striking plate of a club head according to the invention in the cross-sectional view;

[0067] FIG. 13 a microscopic image of the laser-structured connection region of the striking plate of another club head according to the invention in the cross-sectional view;

[0068] FIG. 14 a microscopic image of the laser-structured connection region of the striking plate of the club head of FIG. 13 in the top view;

[0069] FIG. 15 a schematic cross-sectional view of a laser-structured surface of a club head according to the invention in the cross-sectional view;

[0070] FIG. 16a a microscopic image of the laser-structured connection region of the striking plate of another club head according to the invention in the cross-sectional view;

[0071] FIG. 16b a schematic representation of the contour line of the image of FIG. 16a;

[0072] FIG. 17a a microscopic image of the laser-structured connection region of the striking plate of yet another club head according to the invention in the cross-sectional view;

[0073] FIG. 17b a schematic representation of the contour line of the image of FIG. 17a;

[0074] FIG. 18 a schematic representation of a first, preferred variant of a laser-structured connection region of a club head according to the invention in the top view;

[0075] FIG. 19 a schematic representation of a second variant of a laser-structured connection region of a club head according to the invention in the top view;

[0076] FIG. 20 a schematic representation of a third variant of a laser-structured connection region of a club head according to the invention, in the top view;

[0077] FIG. 21 a schematic representation of a fourth variant of a laser-structured connection region of a club head according to the invention, in the top view;

[0078] FIG. 22 a schematic cross-sectional partial view of a club head according to the invention; and

[0079] FIG. 23 an enlarged perspective partial view into the interior of the club head of FIG. 7.DESCRIPTION OF PREFERRED EMBODIMENTS

[0080] FIGS. 1 to 22 show various preferred embodiments of golf club heads 1 according to the invention and parts thereof. Elements that perform the same or a similar function are designated by the same reference numeral, regardless of whether they belong to the same or different embodiments.

[0081] FIGS. 1 to 7 show various types of club heads 1 according to the invention, which together form a complete set of golf club heads. In order to make the inner workings of the club heads 1 visible, they are drawn in a partially transparent manner for illustrative purposes.

[0082] Regardless of the type of club head 1, each has a shell 3 made of a composite material, which forms a large part of the outer surface of the club head 1 and surrounds an interior space of the club head 1. The shell 3 thus forms a base body of the club head 1, which absorbs and transmits the main forces occurring during golf play and forms the main structure of the club head 1. The interior space forms a core made of a gaseous material, in particular air. The club head 1 is thus hollow, with the shell 3 forming a hollow body. The design of the shell 3 as a hollow body with an interior filled with gas, in particular air, results in a particularly light club head with good hitting characteristics.

[0083] The composite material of the shell 3 is preferably a fiber-reinforced plastic material, in particular a carbon fiber-reinforced plastic material. Polyetheretherketone (PEEK) or epoxy resin (EP) is preferably used as the plastic material.

[0084] The club head 1 in each case has a hosel 2, which is used to attach the club head 1 to a club shaft not shown in the figures. The club shaft can be inserted into the hosel 2 and thus into the club head 1 for this purpose.

[0085] A striking plate 6 is attached to the front of the shell 3 in all club types shown in FIGS. 1 to 7. The striking plate 6, which forms an additional element preferably made of a thin-walled metal sheet, preferably of iron, steel, stainless steel, or a light metal such as titanium, may have grooves on its front side to improve the striking properties, as can be seen in FIGS. 1 to 7. The rear side of the striking plate 6, which is not visible in FIGS. 1 to 7 but is shown in FIG. 11, has a laser-structured surface 10 for attachment to the shell 3. The laser-structured surface 10 forms a connection region 61 of the striking plate 6, with which the striking plate 6 rests against the outside of the shell 3.

[0086] In the interior space of the club head 1, which is surrounded by the shell 3 and bounded on the outside, two weighting elements 7 are arranged in each of the types shown in FIGS. 1 to 7. The weighting elements 7 form additional elements and are preferably made of a metal such as tungsten, lead, brass, iron, or an alloy thereof. The weighting elements 7 typically have a single weight of 20 g or higher. The total weight of all weighting elements 7 provided in a club head 1 is preferably 60 g or higher, and even more preferably 100 g or higher. In the embodiments shown here, the weighting elements 7 are each arranged laterally on the club head 1. It has been found that with this arrangement of the weighting elements 7 a particularly good weight distribution can be achieved, while also providing good force transmission within the shell 3.

[0087] The weighting elements 7 are each cast, pressed, or sintered parts which, as a whole, have an irregular geometric shape that is at least partially adapted to the inner surface of the shell 3. The weight distribution achieved by the weighting elements 7 is thus optimally adapted to the shape of the respective racket type.

[0088] The weighting elements 7 each have a connection region 71 with a multi-stepped surface 11, which is clearly visible, for example, in FIGS. 9c and 10b. The weighting elements 7 are each attached to the inner surface of the shell 3 via the connection region 71.

[0089] FIGS. 8a to 8c, 9a to 9c, and 10a and 10b each show an enlarged external view of an exemplary club head type and parts thereof.

[0090] FIGS. 8a and 9a, in conjunction with FIGS. 8b and 9b, show that a base plate 8 is attached to the underside of the club head 1. The base plate 8 resting on the outside of the shell 3 serves to reinforce the club head 1 on its underside, which is usually particularly exposed during golf play and is therefore susceptible to damage. The base plate 8 forms an additional element of the club head 1, and preferably is made of thin-walled sheet metal. It comprises a connection region 81 with a laser-structured surface, which serves to permanently attach the base plate 8 to the shell 3.

[0091] The above-mentioned additional elements, each made of metal, in the form of the striking plate 6, the weighting elements 7, and the base plate 8 are embedded with their connection region 61, 71, and 81, respectively, in the composite material of the shell 3. There is therefore a certain degree of engagement between the shell 3 and the respective additional element 6, 7 or 8. For this purpose, during the manufacture of the club head 1, the composite material of the shell 3 is cast onto the respective additional element 6, 7 or 8. The additional elements 6, 7, 8 are thus cast in a material bonded manner with the composite material of the shell 3. In an alternative manufacturing method, it would also be conceivable to spray the composite material of the shell 3 onto the additional elements 6, 7, 8.

[0092] To make the connection even stronger, the composite material of the shell 3 can comprise an adhesive in the connection regions 61, 71, and 81. The base material of the shell 3 is then coated with an adhesive in the corresponding areas, whereby the adhesive can be regarded as a component of the composite material. The metal parts or additional elements 6, 7, 8, respectively, are then bonded to the shell 3 over a large area. This bonding is particularly advantageous when carried out in situ with low-viscosity, reactive epoxy resins, and is especially advantageous when additionally carried out under vacuum and at elevated temperatures so that the adhesive can optimally wet the surface at low viscosity (preferably between 50-10′000 mPas, in particular 100-500 mPas).

[0093] Due to the laser structuring and / or the multiple steps in the connection region, the surface area relevant for bonding the additional elements 6, 7, 8 is significantly increased. When the composite material is poured, it penetrates the local recesses formed by the steps or laser structuring, so that the additional elements 6, 7, 8 are embedded in the material of the shell 3, creating a particularly tight and strong bond between the components. This significantly increases the strength of the connection between the additional elements 6, 7, 8 and the shell 3, considerably reducing the risk of the additional elements 6, 7, 8 slipping or even detaching from the shell 3.

[0094] Preferably, the connection regions 61, 71, and 81 of the impact plate 6, the weighting elements 7, and the base plate 8 are also roughened. This allows the materials of the additional elements 6, 7, 8 and the shell 3 to interlock even better, thereby making the connection even stronger. The roughening of the surfaces of the respective connection regions 61, 71 and 81 is preferably produced by means of sandblasting, chemical etching and / or flat laser treatment.

[0095] In the cross-sectional view of FIG. 10c, the steps of the multi-stepped surfaces 11 of the connection regions 71 of one of the weighting elements 7 are clearly visible. The steps of the stepped surface 11 provided on the front side of the weighting element 7 each form a surface that is perpendicular to the intended main striking direction H with a deviation of at most 40°, preferably at most 20°. In the embodiment shown in FIG. 10c, the angle α of deviation at which the steps of the stepped surface 11 with their respective surfaces are perpendicular to the intended main striking direction H is approximately 14°. In this way, the forces acting on the club head 1 during impact can be absorbed particularly well in the connection region 71. Tests have shown that the connection of the weighting elements 7 can be further improved by aligning the steps in such a way that they each form a surface perpendicular to the intended main striking direction H. In practice, very good results have already been achieved with a step configuration in which the respective step surfaces are perpendicular to the intended main strike direction H with a maximum deviation of 40°, preferably a maximum of 20°.

[0096] Preferably, all surfaces of the connection regions of the weighting elements 7 facing the intended main striking direction in the projection form a multi-stepped and / or laser-structured surface, whereby the steps of all these surfaces are advantageously aligned in such a way that they each have a surface perpendicular to the intended main striking direction H, with a deviation of at most 40°, preferably a maximum deviation of 20°.

[0097] This further reduced slippage or even detachment of the weighting elements 7 in long-term tests.

[0098] In the rear region, i.e., on the outer surfaces of the respective weighting element 7 that are at least partially oriented in the projection against the intended main striking direction H, the multi-stepped surface 11 preferably forms undercuts relative to the main striking direction H. Such undercuts are provided, for example, in the weighting elements 7 shown in FIG. 9c in the areas marked with the dashed arrows. The strength of the connection of the weighting elements 7 can thus be improved, particularly with regard to the main forces occurring during striking.

[0099] The laser-structured surface 10 of the connection region 61 of the striking plate 6, which can be seen in FIG. 11, comprises a regular geometry with a plurality of parallel grooves that intersect perpendicularly and are arranged at regular intervals. With such a pattern, a particularly strong connection of the striking plate 6 to the shell 3 could be achieved. Due to the regular pattern, the laser structuring of the connection region 61 is also easily recognizable to the naked eye. The distances between the parallel grooves are preferably in the range between 0.1 mm and 0.3 mm, in particular at approximately 0.2 mm, which has proven to be a good compromise between the strength of the connection on the one hand and the amount of work and thermal distortion of the plate during energy input on the other.

[0100] FIG. 11 shows a microscopic image of the connection region between an impact plate 6 with a laser-structured surface 10 and the composite material of a shell 3. The grooves of the laser-structured surface 10, arranged at regular intervals, and the interlocking of the materials of the two components are clearly visible. The components 6 and 3 are thus connected to each other in a form-fitting and material-bonded manner.

[0101] A microscopic image of the connection region between the striking plate 6 and the shell 3 of another club head 1, also according to the invention, is shown in FIG. 13. Here, the laser-structured surface 10 comprises an additional structure with small local elevations and depressions in the intermediate areas 13 arranged between the grooves. The additional structure of the intermediate areas 13 can be achieved by welded metal spatter. The same laser-structured surface 10 is shown in FIG. 10 in the top view. FIG. 15 schematically shows a corresponding contour image. The additional structuring in the intermediate areas 13 further increases the total surface area of the connection region, thereby strengthening the connection between the components.

[0102] FIG. 15 shows that the grooves formed by the laser-structured surface 10 widen in a downward direction in some cases and / or form undercuts 12. By using suitable parameter settings for the preferably pulsed laser input of the grooves, it is possible to easily achieve a widening of the grooves in a downward direction and to provoke the formation of undercuts. Undercuts 12 are also formed by the local elevations in the intermediate surfaces 13. The material of the impact plate 6 can thus be gripped by the composite material of the shell 3, thereby creating a particularly strong bond.

[0103] In terms of manufacturability and effect, the grooves of the laser-structured surface 10 preferably have a width in a range between 30 and 100 μm, in particular between 30 and 50 μm. The depth of the grooves is preferably in at range between 20 and 100 μm, in particular between 30 and 100 μm. Grooves with a width of less than 30 μm, for example in a range between 15 and 30 μm, and / or with a depth of less than 20 μm, for example in a range between 10 and 20 μm, could prove advantageous in the future and depending on their manufacturability using a laser.

[0104] FIG. 16a shows a microscopic image of the laser-structured surface 10 of the striking plate 6 of another club head according to the invention in the cross-sectional view. FIG. 16b shows the contour line in the region of the interfaces for better visibility. Here, too, it is clearly visible how the composite material of the shell 3 engages with the grooves of the laser-structured surface 10 and even undercuts them in the areas of the undercuts 12. Mutual engagement also takes place in the areas of the intermediate surfaces 13, where undercuts 12 are also engaged.

[0105] Another variant of a laser-structured surface 10 with undercuts 12 is shown as a microscopic image in FIG. 17a and as a traced contour line in FIG. 17b. Compared to the embodiment shown in FIGS. 16a and 16b, the structuring of the intermediate surfaces 13 is considerably more pronounced here, i.e., it is of a similar magnitude to the grooves arranged between them.

[0106] FIGS. 18 to 21 show various possible geometric designs of the laser-structured surface 10. FIG. 18 shows the aforementioned preferred arrangement of perpendicularly intersecting grooves. FIGS. 19 and 20 show a laser-structured surface 10 with cross-shaped depressions or elevations in a parallel or staggered arrangement. In the embodiment shown in FIG. 21, the laser-structured surface 10 has circular depressions or elevations. All of the laser-structured surfaces 10 shown in the variants of FIGS. 18 to 21 have a regular geometry with local elevations or depressions, respectively, arranged at uniform intervals.

[0107] In order not to negatively influence the positive properties of the composite material of the shell 3 with regard to elasticity and natural frequencies, the impact plate 6 and the base plate 8 are each designed to be as thin as possible. Preferred thicknesses of the impact plate 6 are in a range of 0.2-0.8 mm, in particular approximately 0.5 mm. Preferred thicknesses of the base plate 8 are in a range of 0.8-1.25 mm.

[0108] FIG. 22 shows that the impact plate 6 preferably has an edge phase 14, i.e., the edge of the impact plate 6 is chamfered. The sheet thickness is preferably tapered by 30-50% toward the edge. Typically, the edge phase 14 is 1-4 mm wide. The grooves of the laser-structured surface 10, however, are advantageously present up to the outer edge. The edge area of the impact plate 6, in particular the edge phase 14, can also be more densely laser-structured in order to further strengthen the bond in this area.

[0109] A further measure, which is preferably used in addition to the laser-structured and / or multi-stepped and optionally roughened surfaces to prevent the weighting element 7 from slipping or detaching, respectively, can be seen in FIG. 23: The shell 3 has a plurality of inwardly projecting protrusions 15, each of which rests against an edge on an outer side of the weighting element 7, thereby restricting its mobility. FIG. 23 also clearly shows the core 4 of the club head 1, which is essentially completely surrounded by the shell 3 and is formed from a gaseous material, such as air in particular. The shell 3 thus forms a hollow body.LIST OF REFERENCE SIGNS1 Club head

[0111] 2 Hosel

[0112] 3 Shell

[0113] 4 Core

[0114] 6 Impact plate

[0115] 61 Connection region

[0116] 7 Weighting element

[0117] 71 Connection region

[0118] 8 Base plate

[0119] 81 Connection region

[0120] 10 Laser-structured surface

[0121] 11 Stepped surface

[0122] 12 Undercut

[0123] 13 Intermediate surface

[0124] 14 Edge phase

[0125] 15 Protrusion

[0126] H Main striking direction

[0127] α Angle

Examples

Embodiment Construction

[0080]FIGS. 1 to 22 show various preferred embodiments of golf club heads 1 according to the invention and parts thereof. Elements that perform the same or a similar function are designated by the same reference numeral, regardless of whether they belong to the same or different embodiments.

[0081]FIGS. 1 to 7 show various types of club heads 1 according to the invention, which together form a complete set of golf club heads. In order to make the inner workings of the club heads 1 visible, they are drawn in a partially transparent manner for illustrative purposes.

[0082]Regardless of the type of club head 1, each has a shell 3 made of a composite material, which forms a large part of the outer surface of the club head 1 and surrounds an interior space of the club head 1. The shell 3 thus forms a base body of the club head 1, which absorbs and transmits the main forces occurring during golf play and forms the main structure of the club head 1. The interior space forms a core made of a ...

Claims

1. A club head for a golf club, comprisingan outer shell manufactured of a composite material; andone or more additional elements formed of metal, each of which is at least partially embedded in the composite material of the shell by means of a connecting region,wherein the connection region of the one or more additional elements is each formed by a laser-structured and / or multi-stepped surface2. The club head according to claim 1, wherein at least one part of the additional element(s) is one or more weighting element(s), each of which is arranged completely inside the shell.

3. The club head according to claim 2, wherein a first and a second of the one or more weighting element(s) are each arranged laterally on the club head with respect to a main striking direction.

4. The club head according to claim 2, wherein the weighting element(s) as a whole each have a geometric shape which is irregular and which is at least partially adapted to the inner surface of the shell.

5. The club head according to claim 1, wherein the composite material comprises an adhesive for bonding the additional element(s) to the composite material of the shell.

6. The club head according to claim 1, wherein at least one of the additional elements is a striking plate which is attached to an outer side of the shell and serves to strike a golf ball.

7. The club head according to claim 1, wherein essentially all surfaces of the connection regions of the additional element(s) which are directed at least partially in the a main striking direction are formed by a multi-stepped and / or laser-structured surface.

8. The club head according to claim 1, wherein the connection region is each formed by a multi-stepped surface, and wherein the steps of the multi-stepped surface each form a surface which is perpendicular to a main striking direction with a deviation of at most 40°.

9. The club head according to claim 1, wherein the connection region each is formed by a laser-structured surface, and wherein the laser-structured surface each comprises a plurality of grooves formed by a laser.

10. The club head according to claim 9, wherein the grooves comprise a greater width in depth than at the surface.

11. The club head according to claim 1, wherein the connection region each is formed by a roughened surface.

12. The club head according to claim 1, wherein the additional element(s) each comprise, with respect to a main striking direction, an undercut.

13. The club head according to claim 1, wherein the additional element(s) are each arranged completely inside the shell-(3), wherein the shell comprises projections projecting into the interior to prevent the additional element(s) from shifting with respect to the shell.

14. The club head according to claim 1, additionally comprising a core made of a gaseous material or of a foam material, which is at least partially surrounded by the shell.

15. A golf club with a club head comprisingan outer shell manufactured of a composite material; andone or more additional elements formed of metal, each of which is at least partially embedded in the composite material of the shell by means of a connecting region,wherein the connection region of the one or more additional elements is each formed by a laser-structured and / or multi-stepped surface.

16. A method for manufacturing a club head, wherein the method comprises at least the step of at least partially embedding one or more additional elements made of metal, each with a connection region, in a composite material of an outer shell of the club head,wherein the connection region of the additional element(s) each is laser-structured and / or multi-stepped before being embedded in the composite material.

17. The club head according to claim 1, wherein the composite material is a fiber-reinforced plastic.

18. The club head according to claim 5, wherein the adhesive is in the form of an epoxy resin.

19. The club head according to claim 9, wherein the plurality of grooves are parallel to and / or perpendicular to each other.

20. The club head according to claim 11, wherein the roughened surface is produced by means of sandblasting, chemical etching, and / or flat laser treatment.

Images