With the ever-increasing popularity and competitiveness of golf, substantial effort and resources are currently being expended to improve golf clubs. Much of the recent improvement activity has involved the combination of the use of new and increasingly more sophisticated materials in concert with advanced club-head engineering. For example, modern “wood-type” golf clubs (notably, “drivers,” “fairway woods,” and “utility or hybrid clubs”), with their sophisticated shafts and non-wooden club-heads, bear little resemblance to the “wood” drivers, low-loft long-irons, and higher numbered fairway woods used years ago. These modern wood-type clubs are generally called “metalwoods” since they tend to be made of strong, lightweight metals, such as titanium.
An exemplary metalwood golf club such as a driver or fairway wood typically includes a hollow shaft having a lower end to which the club-head is attached. Most modern versions of these club-heads are made, at least in part, of a lightweight but strong metal such as titanium alloy. In most cases, the club-head comprises a body to which a face plate (used interchangeably herein with the terms “face” or “face insert” or “striking plate” or “strike plate”) is attached or integrally formed. The strike plate defines a front surface or strike face that actually contacts the golf ball.
Some current approaches to reducing structural mass of a metalwood club-head are directed to making at least a portion of the club-head of an alternative material. Whereas the bodies and face plates of most current metalwoods are made of titanium alloy, several club-heads are available that are made, at least in part, of components formed from either graphite/epoxy-composite (or other suitable composite material) and a metal alloy. Graphite composites have a density of approximately 1.5 g/cm3, compared to titanium alloy which has a density of 4.5 g/cm3, which offers tantalizing prospects for providing more discretionary mass in the club-head.
The ability to utilize such materials to increase the discretionary mass available for placement at various points in the club-head allows for optimization of a number of physical properties of the club-head which can greatly impact the performance obtained by the user. Forgiveness on a golf shot is generally maximized by configuring the golf club head such that the center of gravity (“CG”) of the golf club head is optimally located and the moment of inertia (“MOI”) of the golf club head is maximized.
However, to date there have been relatively few golf club head constructions involving a polymeric material as an integral component of the design. Although such materials possess the requisite light weight to provide for significant weight savings, it is often difficult to utilize these materials in areas of the club head subject to stresses resulting from the high speed impact of the golf ball.
For example, some current metalwoods incorporate weight tracks in the sole to support slidable weights which allow the golfer to adjust the performance characteristics of the club by changing the weight position and effective center of gravity (CG) of the club head. The weight track is generally made from cast titanium to handle the high stress resulting from the high speed impact of the golf ball. Although titanium and titanium alloys are comparatively light in the context of other metals, titanium is still relatively heavy, requires a number of reinforcing ribs and produces undesirably low first modal frequencies (when the ball is struck). A heavier construction for the weight track and ribs means less discretionary weight is available for placement in strategic locations that benefit club performance.
In one embodiment, the golf club head may include a sole insert made of a material suitable to have a part injection molded thereto, and a thermoplastic composite head component overmolded on the sole insert to create a sole insert unit. The sole insert unit is joined to the frame and overlies the sole opening.
The composite head component overmolded on the sole insert may include one or more ribs to reinforce the head, one or more ribs to tune acoustic properties of the head, one or more weight ports to receive a fixed weight in a sole portion of the head, one or more weight tracks to receive one or more slidable weights, any combinations thereof, and other features.
The sole insert may be made from a thermoplastic composite material, thermoplastic carbon composite material, a continuous fiber thermoplastic composite material suitable for thermoforming, as well as other materials.
The weight track may be made from a thermoplastic composite material including a matrix compatible for binding with the sole insert material.
The golf club head may include a sole insert and weight track, each of which is made from a thermoplastic composite material having a compatible matrix to facilitate injection molding the weight track over the sole insert.
The sole insert and weight track each may be made from a thermoplastic carbon composite material having a compatible matrix selected from the group consisting of, for example, polyphenylene sulfide (PPS), nylon, polyamides, polypropylene, thermoplastic polyurethanes, thermoplastic polyureas, polyamide-amides (PAI), polyether amides (PEI), polyetheretherketones (PEEK), and any combination thereof.
The sole insert may also be made from a thermoset composite material suitable for thermosetting and coated with a heat activated adhesive to facilitate the weight track being injection molded over the sole insert.
The frame may be made from a metal material such as, for example, titanium, one or more titanium alloys, aluminum, one or more aluminum alloys, steel, one or more steel allows, and any combination thereof.
The sole and crown inserts may be made of a thermoplastic composite material including fibers such as, for example, glass fibers, aramide fibers, carbon fibers and any combination thereof, and include a thermoplastic matrix selected from the group consisting of polyphenylene sulfide (PPS), polyamides, polypropylene, thermoplastic polyurethanes, thermoplastic polyureas, polyamide-amides (PAI), polyether amides (PEI), polyetheretherketones (PEEK), and any combinations thereof.
The sole insert and/or crown insert may be thermoformed from a continuous fiber composite material.
The golf club head may include a metal frame having a sole opening, a composite laminate crown insert joined to the frame, a composite laminate sole insert joined to the frame and overlying the sole opening, and a thermoplastic composite weight track overmolded on the sole insert.
A method of making the golf club head may include forming a frame having a sole opening, forming a composite laminate sole insert, injection molding a thermoplastic composite head component over the sole insert to create a sole insert unit, and joining the sole insert unit to the frame.
The sole and crown inserts may be formed by thermoforming using composite materials suitable for thermoforming.
The sole and/or crown inserts may be formed by thermosetting using materials suitable for thermosetting.
The thermoset sole and/or crown insert may be coated with a heat activated adhesive to facilitate injection molding a thermoplastic composite component over the sole and/or crown insert, such as one or more weight tracks, weight ports, ribs, supports or other features for strengthening, adding rigidity, acoustic tuning or other purposes.
The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.
The following describes embodiments of golf club heads in the context of a driver-type golf club, but the principles, methods and designs described may be applicable in whole or in part to fairway woods, utility clubs (also known as hybrid clubs) and the like.
The following inventive features include all novel and non-obvious features disclosed herein both alone and in novel and non-obvious combinations with other elements. As used herein, the phrase “and/or” means “and,” “or” and both “and” and “or.” As used herein, the singular forms “a,” “an” and “the” refer to one or more than one, unless the context clearly dictates otherwise. As used herein, the term “includes” means “comprises.”
The following also makes reference to the accompanying drawings which form a part hereof. The drawings illustrate specific embodiments, but other embodiments may be formed and structural changes may be made without departing from the intended scope of this disclosure. Directions and references (e.g., up, down, top, bottom, left, right, rearward, forward, heelward, toeward, etc.) may be used to facilitate discussion of the drawings but are not intended to be limiting. For example, certain terms may be used such as “up,” “down,” “upper,” “lower,” “horizontal,” “vertical,” “left,” “right” and the like. These terms are used where applicable, to provide some clarity of description when dealing with relative relationships, particularly with respect to the illustrated embodiments. Such terms are not, however, intended to imply absolute relationships, positions and/or orientations. For example, with respect to an object, an “upper” surface can become a “lower” surface simply by turning the object over. Nevertheless, it is still the same object. Accordingly, the following detailed description shall not be construed in a limiting sense and the scope of property rights sought shall be define by the appended claims and their equivalents.
In one example, a driver-type club head 10 is shown in
The sole of the frame 24 preferably is integrally formed with a lateral weight track 36, which extends generally parallel to and near the face of the club head and generally perpendicular to the weight track 30. The lateral weight track 36 defines a track or port for mounting (in one exemplary embodiment) one or more slidable weights that are fastened to the weight track. In the example shown in
Unlike
The lateral weight track of
With the single lateral weight design shown in
The frame 24 preferably has a lower sole opening sized and configured to receive the sole insert 28, and an upper crown opening sized and configured to receive the crown insert 26. More specifically, the sole opening receives a sole insert unit including the sole insert 28 and weight track 30 joined thereto (as described below). The sole and crown openings are each formed to have a peripheral edge or recess to seat, respectively, the sole insert unit and crown insert 26, such that the sole and crown inserts are either flush with the frame 24 to provide a smooth seamless outer surface or, alternatively, slightly recessed.
Though not shown, the frame 24 preferably has a face opening to receive a face plate or strike plate 42 that is attached to the frame by welding, braising, soldering, screws or other fastening means.
The frame 24 may be made from a variety of different types of materials but in one example is made of a metal material such as a titanium or titanium alloy (including but not limited to 6-4 titanium, 3-2.5, 6-4, SP700, 15-3-3-3, 10-2-3, or other alpha/near alpha, alpha-beta, and beta/near beta titanium alloys), or aluminum and aluminum alloys (including but not limited to 3000 series alloys, 5000 series alloys, 6000 series alloys, such as 6061-T6, and 7000 series alloys, such as 7075). The frame may be formed by conventional casting, metal stamping or other known processes. The frame also may be made of other metals as well as non-metals. The frame provides a framework or skeleton for the club head to strengthen the club head in areas of high stress caused by the golf ball's impact with the face, such as the transition region where the club head transitions from the face to the crown area, sole area and skirt area located between the sole and crown areas.
In one exemplary embodiment, the sole insert 28 and/or crown insert 26 may be made from a variety of composite and polymeric materials, and preferably from a thermoplastic material, more preferably from a thermoplastic composite laminate material, and most preferably from a thermoplastic carbon composite laminate material. For example, the composite material may be an injection moldable material, thermoformable material, thermoset composite material or other composite material suitable for golf club head applications. One exemplary material is a thermoplastic continuous carbon fiber composite laminate material having long, aligned carbon fibers in a PPS (polyphenylene sulfide) matrix or base. One commercial example of this type of material, which is manufactured in sheet form, is TEPEX® DYNALITE 207 manufactured by Lanxess.
TEPEX® DYNALITE 207 is a high strength, lightweight material having multiple layers of continuous carbon fiber reinforcement in a PPS thermoplastic matrix or polymer to embed the fibers. The material may have a 54% fiber volume but other volumes (such as a volume of 42 to 57%) will suffice. The material weighs 200 g/m2.
Another similar exemplary material which may be used for the crown and sole inserts is TEPEX® DYNALITE 208. This material also has a carbon fiber volume range of 42 to 57%, including a 45% volume in one example, and a weight of 200 g/m2. DYNALITE 208 differs from DYNALITE 207 in that it has a TPU (thermoplastic polyurethane) matrix or base rather than a polyphenylene sulfide (PPS) matrix.
By way of example, the TEPEX® DYNALITE 207 sheet(s) (or other selected material such as DYNALITE 208) are oriented in different directions, placed in a two-piece (male/female) matched die, heated past the melt temperature, and formed to shape when the die is closed. This process may be referred to as thermoforming and is especially well-suited for forming the sole and crown inserts.
Once the crown insert and sole insert are formed (separately) by the thermoforming process just described, each is cooled and removed from the matched die. The sole and crown inserts are shown as having a uniform thickness, which lends itself well to the thermoforming process and ease of manufacture. However, the sole and crown inserts may have a variable thickness to strengthen select local areas of the insert by, for example, adding additional plies in select areas to enhance durability, acoustic or other properties in those areas.
As shown in
In an alternative embodiment, the sole insert 28 and/or crown insert 26 can be made by a process other than thermoforming, such as injection molding or thermosetting. In a thermoset process, the sole insert and/or crown insert may be made from prepreg plies of woven or unidirectional composite fiber fabric (such as carbon fiber) that is preimpregnated with resin and hardener formulations that activate when heated. The prepreg plies are placed in a mold suitable for a thermosetting process, such as a bladder mold or compression mold, and stacked/oriented with the carbon or other fibers oriented in different directions. The plies are heated to activate the chemical reaction and form the sole (or crown) insert. Each insert is cooled and removed from its respective mold.
The carbon fiber reinforcement material for the thermoset sole/crown insert may be a carbon fiber known as “34-700” fiber, available from Grafil, Inc., of Sacramento, Calif., which has a tensile modulus of 234 Gpa (34 Msi) and tensile strength of 4500 Mpa (650 Ksi). Another suitable fiber, also available from Grafil, Inc., is a carbon fiber known as “TR50S” fiber which has a tensile modulus of 240 Gpa (35 Msi) and tensile strength of 4900 Mpa (710 Ksi). Exemplary epoxy resins for the prepreg plies used to form the thermoset crown and sole inserts are Newport 301 and 350 and are available from Newport Adhesives & Composites, Inc., of Irvine, Calif.
In one example, the prepreg sheets have a quasi-isotropic fiber reinforcement of 34-700 fiber having an areal weight of about 70 g/m2 and impregnated with an epoxy resin (e.g., Newport 301), resulting in a resin content (R/C) of about 40%. For convenience of reference, the primary composition of a prepreg sheet can be specified in abbreviated form by identifying its fiber areal weight, type of fiber, e.g., 70 FAW 34-700. The abbreviated form can further identify the resin system and resin content, e.g., 70 FAW 34-700/301, R/C 40%.
In a preferred embodiment, the weight track 30 which has more details and 3-D features than the sole insert 28, is made from the same, similar or at least compatible material as the sole insert to allow the weight track to be injection molded, overmolded, or insert molded over the sole insert to bond the two parts together to form the sole insert unit. The weight track 30 preferably is made from a polymeric material suitable for injection molding, preferably a thermoplastic material, more preferably a thermoplastic composite laminate material, and most preferably a thermoplastic carbon composite laminate material. One exemplary material suitable for injection molding is a thermoplastic carbon fiber composite material having short, chopped fibers in a PPS (polyphenylene sulfide) base or matrix. For example, the weight track material may include 30% short carbon fibers (by volume) having a length of about 1/10 inch, which reinforces the PPS matrix.
One example of a commercial material that may be used for the weight track is RTP 1385 UP, made by RTP Company. Other examples include nylon, RTP 285, RTP 4087 UP and RTP 1382 UP. In a preferred example, the crown insert, sole insert and weight track 30 are made from compatible materials capable of bonding well to one another such as polymeric materials having a common matrix or base, or at least complementary matrices. For example, the crown insert and sole insert may be made from continuous fiber composite material well suited for thermoforming while the weight track is made of short fiber composite material well suited for injection molding (including insert molding and overmolding), with each having a common PPS base.
The sole insert unit is formed by placing the thermoplastic composite sole insert 28 in a mold and injection molding the thermoplastic weight track 30 over the sole insert (as, for example, by insert molding or overmolding). The injection molding process creates a strong fusion-like bond between the sole insert and weight track due to their material compatibility, which preferably includes a compatible polymer/matrix (PPS in one preferred example). The terms injection molding (over), insert molding and overmolding generally refer to the same process, but to the extent there are differences, all such processes are believed to be sufficiently similar as to be suitable for forming the sole insert unit.
In the alternative process in which the sole insert 28 is formed using a thermosetting material, the thermoset sole insert and thermoplastic weight track 30 are not compatible materials and will not bond well if left untreated. Accordingly, before the injection molding, insert molding, or overmolding step, the thermoset sole insert 28 preferably is coated with a heat activated adhesive as, for example, ACA 30-114 manufactured by Akron Coating & Adhesive, Inc. ACA 30-114 is a heat-activated water-borne adhesive having a saturated polyurethane with an epoxy resin derivative and adhesion promoter designed from non-polar adherents. It will be appreciated that other types of heat-activated adhesives also may be used.
After the coating step, the coated thermoset sole insert is then placed in a mold and the thermoplastic composite weight track material is overmolded (or injection molded) over the sole insert as described above. During the injection molding step, heat activates the adhesive coating on the sole insert to promote bonding between the sole insert and the weight track material.
Notably, though not necessary, the alternative thermoplastic composite sole insert made using a thermoforming process, as described above, also may be coated with a heat-activated adhesive prior to the overmolding step to promote an even stronger bond with the main body, notwithstanding that the thermoplastic sole insert and weight track thermoplastic material already are compatible for bonding if they have common or at least complementary matrices.
If the crown insert is made from a thermoset material and process, there is no need to coat the crown insert because no thermoplastic material is overmolded to the crown insert in the exemplary embodiments described herein. In the event additional thermoplastic features or 3-D details are overmolded on the crown insert, the same bonding principles discussed with respect to the weight track and sole insert apply.
Once the sole insert unit (sole insert 28 and weight track 30) and crown insert 26 are formed, they are joined to the frame 24 in a manner that creates a strong integrated construction adapted to withstand normal stress, loading and wear and tear expected of commercial golf clubs. For example, the sole insert unit and crown insert each may be bonded to the frame using epoxy adhesive, with the crown insert seated in and overlying the crown opening and the sole insert unit seated in and overlying the sole opening. Alternative attachment methods include bolts, rivets, snap fit, adhesives, other known joining methods or any combination thereof.
Equally important, since the ribs are injection molded they can have a wide variety of shapes, sizes, orientations, and locations on the sole insert to adjust and fine tune acoustic properties of the club head. It can be seen in
The composite sole and weight track disclosed in various embodiments herein overcome manufacturing challenges associated with conventional club heads having titanium or other metal weight tracks, and replace a relatively heavy weight track with a light composite material (freeing up discretionary mass which can be strategically allocated elsewhere within the club head). For example, additional ribs can be strategically added to the hollow interior of the club head and thereby improve the acoustic properties of the head. Ribs can be strategically located to strengthen or add rigidity to select locations in the interior of the head. Discretionary mass in the form of ribs or other features also can be strategically located in the interior to shift the effective CG fore or aft, toeward or heelward or both (apart from any further CG adjustments made possible by slidable weight features).
Also, embodiments described herein having continuous fiber composite sole and crown inserts are especially effective in providing improved structural support and stiffness to the club head, as well as freeing up discretionary mass that can be allocated elsewhere.
In the embodiment shown in
As shown in
Though not shown, the frame 224 preferably has a face opening to receive a face plate or strike plate 242 that is attached to the frame by welding, braising, soldering, screws or other fastening means.
The sole of the frame 324 preferably is integrally formed with a lateral weight track 336, which extends generally parallel to and near the face of the club head and generally perpendicular to the weight track 330. The lateral weight track 336 defines a track or port for mounting (in one exemplary embodiment) one or more slidable weights that are fastened to the weight track. In the present embodiment the lateral weight track 336 slideably mounts only on one lateral weight 341. The weight 341 may comprise a single weight element, multiple weight elements or two stacked weight elements fastened together by a screw 340.
The lateral weight track of
The frame 324 preferably has two lower sole openings 329a and 329b sized and configured to receive the sole inserts 328a and 328b respectively, and an upper crown opening 331 sized and configured to receive the crown insert 326. The sole and crown openings are each formed to have a peripheral edges or recess 352 as shown in
Though not shown, the frame 324 preferably has a face opening to receive a face plate or strike plate 342 that is attached to the frame by welding, braising, soldering, screws or other fastening means.
In the golf club heads of the present invention, the ability to adjust the relative magnitude of the slidably adjusted weights and rearward weights coupled with the weight saving achieved by incorporation of the composite sole and crown inserts allows for a large range of variation of a number properties of the club-head all of which affect the ultimate club-head performance including both the position of the CG of the club-head and its various MOI values.
Generally, the center of gravity (CG) of a golf club head is the average location of the weight of the golf club head or the point at which the entire weight of the golf club-head may be considered as concentrated so that if supported at this point the head would remain in equilibrium in any position. A club head origin coordinate system can be defined such that the location of various features of the club head, including the CG can be determined with respect to a club head origin positioned at the geometric center of the striking surface and when the club-head is at the normal address position (i.e., the club-head position wherein a vector normal to the club face substantially lies in a first vertical plane perpendicular to the ground plane, the centerline axis of the club shaft substantially lies in a second substantially vertical plane, and the first vertical plane and the second substantially vertical plane substantially perpendicularly intersect).
The head origin coordinate system defined with respect to the head origin includes three axes: a z-axis extending through the head origin in a generally vertical direction relative to the ground; an x-axis extending through the head origin in a toe-to-heel direction generally parallel to the striking surface (e.g., generally tangential to the striking surface at the center) and generally perpendicular to the z-axis; and a y-axis extending through the head origin in a front-to-back direction and generally perpendicular to the x-axis and to the z-axis. The x-axis and the y-axis both extend in generally horizontal directions relative to the ground when the club head is at the normal address position. The x-axis extends in a positive direction from the origin towards the heel of the club head. The y axis extends in a positive direction from the head origin towards the rear portion of the club head. The z-axis extends in a positive direction from the origin towards the crown. Thus for example, and using millimeters as the unit of measure, a CG that is located 3.2 mm from the head origin toward the toe of the club head along the x-axis, 36.7 mm from the head origin toward the rear of the clubhead along the y-axis, and 4.1 mm from the head origin toward the sole of the club head along the z-axis can be defined as having a CGx of −3.2 mm, a CGy of −36.7 mm, and a CGz of −4.1 mm.
Further as used herein, Delta 1 is a measure of how far rearward in the club head body the CG is located. More specifically, Delta 1 is the distance between the CG and the hosel axis along the y axis (in the direction straight toward the back of the body of the golf club face from the geometric center of the striking face). It has been observed that smaller values of Delta 1 result in lower projected CGs on the club head face. Thus, for embodiments of the disclosed golf club heads in which the projected CG on the ball striking club face is lower than the geometric center, reducing Delta 1 can lower the projected CG and increase the distance between the geometric center and the projected CG. Recall also that a lower projected CG creates a higher dynamic loft and more reduction in backspin due to the z-axis gear effect. Thus, for particular embodiments of the disclosed golf club heads, in some cases the Delta 1 values are relatively low, thereby reducing the amount of backspin on the golf ball helping the golf ball obtain the desired high launch, low spin trajectory.
Similarly Delta 2 is the distance between the CG and the hosel axis along the x axis (in the direction straight toward the back of the body of the golf club face from the geometric center of the striking face).
Adjusting the location of the discretionary mass in a golf club head as described above can provide the desired Delta 1 value. For instance, Delta 1 can be manipulated by varying the mass in front of the CG (closer to the face) with respect to the mass behind the CG. That is, by increasing the mass behind the CG with respect to the mass in front of the CG, Delta 1 can be increased. In a similar manner, by increasing the mass in front of the CG with the respect to the mass behind the CG, Delta 1 can be decreased.
In addition to the position of the CG of a club-head with respect to the head origin another important property of a golf club-head is a projected CG point on the golf club head striking surface which is the point on the striking surface that intersects with a line that is normal to the tangent line of the ball striking club face and that passes through the CG. This projected CG point (“CG Proj”) can also be referred to as the “zero-torque” point because it indicates the point on the ball striking club face that is centered with the CG. Thus, if a golf ball makes contact with the club face at the projected CG point, the golf club head will not twist about any axis of rotation since no torque is produced by the impact of the golf ball. A negative number for this property indicates that the projected CG point is below the geometric center of the face.
In terms of the MOI of the club-head (i.e., a resistance to twisting) it is typically measured about each of the three main axes of a club-head with the CG as the origin of the coordinate system. These three axes include a CG z-axis extending through the CG in a generally vertical direction relative to the ground when the club head is at normal address position; a CG x-axis extending through the CG origin in a toe-to-heel direction generally parallel to the striking surface (e.g., generally tangential to the striking surface at the club face center), and generally perpendicular to the CG z-axis; and a CG y-axis extending through the CG origin in a front-to-back direction and generally perpendicular to the CG x-axis and to the CG z-axis. The CG x-axis and the CG y-axis both extend in generally horizontal directions relative to the ground when the club head is at normal address position. The CG x-axis extends in a positive direction from the CG origin to the heel of the club head. The CG y-axis extends in a positive direction from the CG origin towards the rear portion of the golf club head. The CG z-axis extends in a positive direction from the CG origin 150 towards the crown 112. Thus, the axes of the CG origin coordinate system are parallel to corresponding axes of the head origin coordinate system. In particular, the CG z-axis is parallel to z-axis, the CG x-axis is parallel to x-axis, and CG y-axis is parallel to y-axis.
Specifically, a club head as a moment of inertia about the vertical axis (“Izz”), a moment of inertia about the heel/toe axis (“Ixx”), and a moment of inertia about the front/back axis (“Iyy”). Typically, however, the MOI about the z-axis (Izz) and the x-axis (Ixx) is most relevant to club head forgiveness.
A moment of inertia about the golf club head CG x-axis (Ixx) is calculated by the following equation:
Ixx=∫(y2+z2)dm (1)
where y is the distance from a golf club head CG xz-plane to an infinitesimal mass dm and z is the distance from a golf club head CG xy-plane to the infinitesimal mass dm. The golf club head CG xz-plane is a plane defined by the golf club head CG x-axis and the golf club head CG z-axis. The CG xy-plane is a plane defined by the golf club head CGx-axis and the golf club head CG y-axis.
Similarly, a moment of inertia about the golf club head CG z-axis (Izz) is calculated by the following equation:
Izz=∫(x2+y2)dm (2)
where x is the distance from a golf club head CG yz-plane to an infinitesimal mass dm and y is the distance from the golf club head CG xz-plane to the infinitesimal mass dm. The golf club head CG yz-plane is a plane defined by the golf club head CG y-axis and the golf club head CG z-axis.
A further description of the coordinate systems for determining CG positions and MOI can be found US Patent Publication No. 2012/0172146 A1 publishing on Jul. 5, 2012, the entire contents of which is incorporated by reference herein.
As shown in Table 1 below, the clubs of the present invention are able to achieve extremely high ranges of CGx, CGz, Delta 1 and Delta 2 and Ixx, Izz and projected CG position “BP” within the adjustability ranges of the club head. The values measured in Table 1 where obtained for a club-head having a volume of 452 cm3 when measured with an open front track and varying the distribution of the total discretionary weight as represented by the total; weight of the slidably adjusted weight 236 and the rearward weight 262 (which in the below example totals 44 g) by distributing it between the “front position i.e. the center point of the weight track 236 and the back position ie the location of the weight port of rearward weight 262.
The overmolded thermoplastic component described herein, exemplified by the weight track and ribs/support matrix incorporated into the weight track, illustrates the possibilities for adding design complexities and intricacies to the sole and crown portions of the club head, by overmolding or injection molding 3-dimensional or other features while integrating large composite portions of the head with metal portions. In addition to the one or more weight tracks, and support members and ribs described herein, incorporation of other features may also be facilitated to differing degrees by their overmolding or injection molding over a composite laminate sole and/or crown insert or, alternatively, over a composite laminate shell forming the crown, sole and/or skirt of the club head, as described herein, such features including;
For example, as disclosed in U.S. Pat. No. 7,540,811 a golf club head may have a volume equal to the volumetric displacement of the club head body. In other words, for a golf club head with one or more weight ports within the head, it is assumed that the weight ports are either not present or are “covered” by regular, imaginary surfaces, such that the club head volume is not affected by the presence or absence of ports. A golf club head of the present application can be configured to have a head volume between about 110 cm3 and about 600 cm3. In more particular embodiments, the head volume is between about 250 cm3 and about 500 cm3. In yet more specific embodiments, the head volume is between about 300 cm3 and about 500 cm3, between 300 cm3 and about 360 cm3, between about 300 cm3 and about 420 cm3 or between about 420 cm3 and about 500 cm3.
The designs, embodiments and features described herein may also be combined with other features and technologies in the club-head including;
An additional embodiment of a golf club head 400 is shown in
The lateral weight track 430 is very similar to the weight track discussed above. Like the weight track 36, the weight track 430 spans much of the width of the sole and allows the weight 432 to be positioned proximate to the toe of the club head at one end of the track or proximate to the heel (and hosel) at the other end of the track. Likewise, the lateral (or heel-toe) weight track also is located forward on the sole, proximate to the club head's ball-striking surface or face area 412. In modest contrast, the weight track 430 has enlarged ends at the toe side and heel side. The weight track 430 also connects with a heel-side shaft connection port used to provide a fastener opening for connecting a removable shaft and/or FCT component to the club head.
The frame 424 may be made from a variety of different types of materials but in one example is made of a metal material such as a titanium or titanium alloy (including but not limited to 6-4 titanium, 3-2.5, 6-4, SP700, 15-3-3-3, 10-2-3, or other alpha/near alpha, alpha-beta, and beta/near beta titanium alloys), or aluminum and aluminum alloys (including but not limited to 3000 series alloys, 5000 series alloys, 6000 series alloys, such as 6061-T6, and 7000 series alloys, such as 7075). The frame may be formed by conventional casting, metal stamping or other known processes. The frame also may be made of other metals as well as non-metals. The frame provides a framework or skeleton for the club head to strengthen the club head in areas of high stress caused by the golf ball's impact with the face, such as the transition region where the club head transitions from the face to the crown area, sole area and skirt area located between the sole and crown areas.
In one exemplary embodiment, the sole insert 28 and/or crown insert 26 may be made from a variety of composite and polymeric materials, preferably from a thermoplastic material, more preferably from a thermoplastic composite laminate material, and most preferably from a thermoplastic carbon composite laminate material. For example, the composite material may be an injection moldable material, thermoformable material, thermoset composite material or other composite material suitable for golf club head applications. One exemplary material is a thermoplastic continuous carbon fiber composite laminate material having long, aligned carbon fibers in a PPS (polyphenylene sulfide) matrix or base. One commercial example of this type of material, which is manufactured in sheet form, is TEPEX® DYNALITE 207 manufactured by Lanxess.
Additional information regarding materials and properties suitable for the sole and crown inserts is discussed above.
As shown in
The tie rib 444 preferably extends in a generally lateral heel-toe direction and is positioned generally midway between fore and aft ends of the opening 442. The tie rib 444 preferably has one or more raised portions 448 along its length, with channels or recesses therebetween, to create an undulating profile that preferably mates or nests with a complementary profile in the underside (i.e., interior) surface of the sole insert 428. The sole insert 428 preferably is adhered to the tie rib 444 and to a complementary sized and shaped recessed shelf 450 extending along the periphery of the sole insert opening 442. The sole insert may be secured to the main body 424 in other ways including the use of fasteners or other bonding techniques besides adhesion mentioned above.
A threaded weight 454 is shown threadably received in one of the fixed weight ports 446, which provides a complementary shaped threaded opening to receive the weight. Fixed weight(s) 454 may be removably fastened to the toe-side aft weight port, heel-side aft weight port, or both.
As shown in Table 2 below, one or more embodiments of the present disclosure are able to achieve high MOI (Ixx and Izz), relatively low CG (CGz) and a desirable Center of Gravity projection on the club face, also known as “balance point on the face” (BP Proj.). “Front d mass” denotes the mass of the slidable weight 432 in the lateral weight track 430. For example, the front slidable weight may be 10 g, 20 g or 15 g, as well as other values. “Back d mass” denotes the mass of the fixed aft weight(s), and includes the combined mass of weights in both weight ports 446a, b if two weights are installed. The back d mass (one or two weights), for example, may be 20 g, 10 g, 15 g or some other value. CGx and CGz represent center of gravity locations on the x and z coordinate axes, respectively.
Delta 1 (D1) represents the distance between the club head's CG and its hosel axis along the Y axis (in a direction straight toward the back of the body of the club head face from the geometric center of the face). Thus, for embodiments disclosed herein in which the projected CG (BP Proj.) on the ball striking face is lower than the geometric center, reducing Delta 1 produces a lower projected CG and a lower dynamic loft and creates a desirable further reduction in backspin due to the Z-axis gear effect. Thus, the embodiment of
“Mass” denotes the mass of the club head in grams. Ixx and Izz denote the moment of inertia of the club head about the x and z axes, respectively.
The values in Table 2 below represent club heads having a composite crown/composite sole and volume of about 460 cm3.
In this instance the foregoing properties and values are achieved with a laterally adjustable, forward-located weight and a pair of fixed weight ports located centrally and rearwardly on the club head, both of which may be integrally formed and cast as part of the main body or frame. The foregoing properties and values may also be achieved with relatively light polymer (or composite) sole and crown inserts.
A method of making a golf club may include one or more of the following steps:
In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the invention and should not be taken as limiting the scope of the invention. Rather, the scope of the invention is defined by the following claims. We therefore claim as our invention all that comes within the scope and spirit of these claims.
This application is a continuation of U.S. patent application Ser. No. 15/254,999, filed Sep. 1, 2016, which application is a continuation of U.S. patent application Ser. No. 15/087,002, filed Mar. 31, 2016, which application claims the benefit of U.S. Provisional Application No. 62/205,601, which was filed on Aug. 14, 2015, all of which applications are incorporated herein by reference in their entireties.
Number | Date | Country | |
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62205601 | Aug 2015 | US |
Number | Date | Country | |
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Parent | 15254999 | Sep 2016 | US |
Child | 16058845 | US | |
Parent | 15087002 | Mar 2016 | US |
Child | 15254999 | US |