Patent Description:
<CIT> discloses an iron-type golf club head having a recess in the sole for receiving a weight member.

<CIT> discloses a golf club head that includes a metallic section, a polymeric section, and an adhesive material. The metallic section defines an opening and the polymeric section extends over the opening. The adhesive material is disposed between the metallic section and the polymeric section to form an adhesive joint therebetween.

<CIT> discloses golfing irons provided with weight balancing plugs and metal powder. Two plugs are located in a bore means in the head; one plug is elongated and less dense than the head metal; another plug is short and located at the heel end of the bore means; and the metal powder particles are confined between the plugs and have greater density than the head metal.

There is a need in the art for an iron-type golf club head having improved mass distribution for inertial improvement, while also maintaining the aesthetics of a full muscle-back iron.

The invention described herein is an iron-type golf club head having an optimized mass distribution while also having the aesthetics of a full muscle-back iron. The iron-type golf club head is as defined in the appended claims.

This disclosure generally relates to sports equipment and relates more particularly to golf club heads and related methods.

The iron-type golf club described herein provides both the visual aesthetic of a traditional muscle-back iron-type golf club head, the mass properties of more forgiving cavity back iron-type golf club heads, and the ability to adjust club head center of gravity provided by a detachable CTP weight. The iron-type golf club head comprises a back cavity, which allows more mass to be moved to the perimeter of the golf club head. A lightweight back cavity component or lightweight component is attached within the back cavity. The golf club head further comprises a CTP weight received with a void in the lightweight component allowing for the change of mass properties by configuring the mass of the CTP weight.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "include," and "have," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, device, or apparatus that comprises a list of elements is not necessarily limited to those elements but may include other elements not expressly listed or inherent to such process, method, system, article, device, or apparatus.

It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the apparatus, methods, and/or articles of manufacture described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein.

Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings.

The aspects of the golf club described herein may be applied to one or more golf clubs within a set of irons. In some embodiments, the set of irons comprises irons having varying clubhead size, shaft length, lie angle, loft angle, head weight, and/or other parameters. Each clubhead in the set of irons can be numbered according to the convention with numbers ranging from <NUM> to <NUM>. Most commonly, a set is numbered from <NUM> to <NUM>, wedge, and utility clubs. Furthermore, the set of irons can comprise one or more wedges, which have a loft angle higher than the numbered irons.

In some embodiments, the golf club head <NUM> can be a wedge. In many embodiments, the loft angle of the golf club head <NUM> is less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, or less than approximately <NUM> degrees. Further, in many embodiments, the loft angle of the golf club head <NUM> is greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, or greater than approximately <NUM> degrees.

In many embodiments, the loft angle of the golf club head is less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, less than approximately <NUM> degrees, or less than approximately <NUM> degrees. Further, in many embodiments, the loft angle of the golf club head is greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, greater than approximately <NUM> degrees, or greater than approximately <NUM> degrees.

In many embodiments, the golf club head can comprise a total volume of between <NUM> and <NUM><NUM> (<NUM> cubic inches and <NUM> cubic inches). In some embodiments, the total volume of the golf club head can be between <NUM><NUM> (<NUM> cubic inches) and <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches) and <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches) and <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches) and <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches) and <NUM><NUM> (<NUM> cubic inches), or <NUM><NUM> (<NUM> cubic inches) and <NUM><NUM> (<NUM> cubic inches). In other embodiments, the total volume of the golf club head can be <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches), <NUM><NUM> (<NUM> cubic inches), or <NUM> (<NUM> cubic inches).

In many embodiments, the golf club head can comprise a total mass of between <NUM> grams and <NUM> grams. In some embodiments, the golf club head can comprise a total mass of between <NUM> grams and <NUM> grams, <NUM> grams and <NUM> grams, <NUM> grams and <NUM> grams, <NUM> grams and <NUM> grams, <NUM> grams and <NUM> grams, <NUM> grams and <NUM> grams, <NUM> grams and <NUM> grams, <NUM> grams to <NUM> grams, <NUM> grams to <NUM> grams, <NUM> grams and <NUM> grams, <NUM> grams, and <NUM> grams, or <NUM> grams and <NUM> grams. In other embodiments, the total mass can be <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, <NUM> grams, or <NUM> grams.

The iron-type golf club head comprises a main body having a back cavity, which allows more mass to be moved to the perimeter of the golf club head. A lightweight back cavity component or lightweight insert is attached within the back cavity. The golf club head further comprises a CTP weight received with a void in the lightweight component allowing for the change of mass properties by configuring the mass of the CTP weight to move the center of gravity of the golf club head toward the toe or toward the heel.

Referring to <FIG>, the main body <NUM> of the iron-type golf club head <NUM> has a toe end <NUM>, a heel end, a front having a strikeface <NUM> for impacting a golf ball, a hosel, a top-rail <NUM>, a sole, a hosel configured for receiving a shaft, a rear opposite the front, and a back cavity <NUM> surrounded and defined by a rear surface <NUM> of the striking face <NUM>, and a perimeter sidewall <NUM> surrounding the back cavity <NUM> formed by the top-rail <NUM>, the sole <NUM>, the toe end <NUM>, and the heel end <NUM>. The main body <NUM> sole <NUM> extends toward the rear of the main body <NUM> further than the top-rail <NUM>. Thus, the lower portions of the perimeter sidewall <NUM> extend further to the rear than the upper portions of the perimeter sidewall <NUM>. The back cavity <NUM> comprises a depth, and the back cavity <NUM> depth is greater in a lower, soleward portion than in the upper, top-rail <NUM> portion of the back cavity <NUM>.

<FIG>, and <FIG>all refer to a single embodiment of the golf club head <NUM>. All numbered features and elements are the golf club head <NUM> features and elements. <FIG> also share these elements, but also have elements pertaining to the methods of manufacture.

Referring to <FIG>, the club head <NUM> defines a ground plane <NUM> that is tangent to the sole <NUM> when the club head <NUM> is at an address position.

Referring to <FIG> and <FIG>, the perimeter sidewall <NUM> is generally perpendicular to the rear surface <NUM>. The perimeter sidewall <NUM> may vary from perpendicular by plus or minus <NUM> degrees. The heel end <NUM> of the golf club head <NUM> may have an aperture <NUM> through the heel end <NUM>, so the aperture <NUM> opens to an exterior surface of the heel end <NUM> and opens to the back cavity <NUM>.

Referring to <FIG> and <FIG>, the perimeter sidewall <NUM> comprises a locking groove <NUM> in the perimeter sidewall <NUM> along the perimeter of the back cavity <NUM>. The locking groove <NUM> is recessed into the perimeter sidewall <NUM> surrounding the rear surface <NUM>. The locking groove <NUM> is recessed into the perimeter sidewall <NUM> in a direction parallel to the rear surface <NUM> of the striking face <NUM>. (see <FIG>).

Referring to <FIG>, the locking groove <NUM> comprises a locking groove bottom and two locking groove sidewalls. The locking groove is open to the main body <NUM> back cavity <NUM> prior to the back cavity <NUM> receives the lightweight insert <NUM>. The locking groove <NUM> can define a plane, wherein the plane intersects a center of the locking groove <NUM> bottom around the perimeter sidewall <NUM>, and wherein the plane is essentially parallel to the striking face <NUM>.

Still referring to <FIG>, the locking groove <NUM> may have a single constant depth. In other embodiments, the depth of the locking groove <NUM> may vary. The locking groove <NUM> may have a single, constant width. In other embodiments, the locking groove <NUM> width may vary. The locking groove <NUM> may be continuous around the entire perimeter sidewall <NUM>. The locking groove <NUM> may be discontinuous, and form multiple portions separated from one another around the perimeter sidewall <NUM>. The locking groove <NUM> may comprise projections or depressions along the locking <NUM> bottom. The locking groove <NUM> sidewalls may comprise depressions or recesses in locking groove <NUM> sidewalls wherein the depressions or recessions are perpendicular to the locking wall sidewalls <NUM> (Figure not shown).

Still referring to <FIG>, the locking groove <NUM> depth may be in the range of <NUM> (<NUM> inch) to <NUM> (<NUM> inch). The locking groove <NUM> depth may be <NUM> (<NUM>, inch) <NUM> (<NUM> inch), <NUM> (<NUM> inch), <NUM> (<NUM> inch), or <NUM> (<NUM> inch). The locking groove <NUM> width may be in a range of <NUM> (<NUM> inch) to <NUM> (<NUM> inch). The locking groove <NUM> width may be <NUM> (<NUM>, inch), <NUM> (<NUM>-inch), <NUM> (<NUM> inch), <NUM> (<NUM> inch), or <NUM> (<NUM> inch).

Referring to <FIG>, the sole <NUM> further comprises a CTP weight groove <NUM>. The CTP weight groove <NUM> comprises a CTP weight groove <NUM> axis along the length of the CTP weight groove <NUM> so the CTP weight groove <NUM> axis is equidistant from the CTP weight groove <NUM> edges along the length of the CTP weight groove <NUM> from the golf club head <NUM> heel end <NUM> to the golf club head <NUM> toe end <NUM>. The CTP weight groove <NUM> axis is parallel to the rear surface <NUM> of the striking face <NUM>. The central CTP weight groove <NUM> axis defines an angle with the ground plane <NUM> when the golf club head is in an address position. The CTP weight groove <NUM> receives part of the length of the CTP weight <NUM> when the CTP weight <NUM> is received within the void <NUM>.

Still referring to <FIG>, the CTP weight groove <NUM> axis angle in relation to the ground plane <NUM> when the golf club head <NUM> is at an address position may be between <NUM> degrees and <NUM> degrees. The CTP weight groove <NUM> axis angle may be <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> degrees.

Still referring to <FIG>, the CTP weight groove <NUM> comprises a length, a width, and a depth of recession. The CTP weight groove <NUM> depth of recession is measured from and in relation to the surface of the surrounding sole <NUM> perimeter sidewall <NUM> so the CTP weight groove <NUM> defines a recess in the sole <NUM> perimeter sidewall <NUM>. The CTP weight groove <NUM> depth of recession gradually decreases from closest to the golf club head <NUM> heel end <NUM> as it extends toward the golf club head toe end <NUM>. The CTP weight groove <NUM> depth width gradually decreases from closest to the golf club head heel end <NUM> as it extends toward the golf club head toe end <NUM>. The CTP weight <NUM> groove <NUM> tapers to a toe end <NUM> termination where the CTP weight groove <NUM> depth and CTP weight groove <NUM> width are each zero. The CTP weight groove <NUM> further comprises a cross-sectional profile. The CTP weight groove <NUM> cross-sectional profile may be constant. Alternately, the CTP weight groove <NUM> cross-sectional profile may gradually change from closest to the golf club head heel end <NUM> toward the golf club head toe end <NUM>. The CTP weight groove <NUM> cross-sectional profile may decrease from closest to the golf club head heel end <NUM> toward the golf club head toe end <NUM>. The CTP weight groove <NUM> cross-sectional profile may comprise a radius of curvature. The CTP weight groove <NUM> comprises edges along the points wherein the recession from the sole <NUM> perimeter sidewall <NUM> begins.

Referring to <FIG> and <FIG>, the golf club head <NUM> main body <NUM> further defines a hole or aperture <NUM> in the heel end <NUM> of the golf club head <NUM> main body <NUM> that extends from an outer surface of the main body <NUM> into the back cavity <NUM>. The aperture <NUM> comprises a depth and a cross-sectional area. The aperture <NUM> defines a central axis wherein the aperture <NUM> central axis extends along with the depth of the aperture <NUM> through a geometric center of the aperture <NUM> and essentially parallel the strikeface rear surface <NUM>. In some embodiments, the aperture <NUM> comprises a circular cross-sectional shape having a radius of curvature. In other embodiments, the aperture <NUM> comprises any geometric cross-sectional shape. (See <FIG>) The aperture <NUM> extends from the exterior surface of the heel end <NUM> of the golf club head main body <NUM> through the heel end <NUM> of the perimeter sidewall <NUM>.

Still referring to <FIG> and <FIG>, the central axis of the aperture <NUM> also extends parallel to the CTP weight groove <NUM> axis. In one embodiment, the cross-sectional shape of the aperture <NUM> in the heel end <NUM> of the golf club main body <NUM> can be circular, the cross-sectional shape of the CTP weight groove <NUM> can be a circular section at any location along the CTP weight groove <NUM> length, wherein the radius of curvature of the aperture <NUM> and the CTP weight groove <NUM> radius of curvature are the same.

The main body <NUM> of the golf club head <NUM> can comprise steel alloys, titanium alloys, aluminum alloys, plastic polymers, carbon fibers, composites, thermoplastic composites, or any other suitable material.

<FIG> all refer to a single embodiment of the golf club head <NUM>. All numbered features and elements are the golf club head <NUM> features and elements.

Referring to <FIG> <FIG>, <FIG>, and <FIG>, the lightweight component <NUM> resides in the back cavity <NUM> of the main body <NUM> and provides a clean muscle-back aesthetic. The lightweight component <NUM> comprises an upper portion <NUM>, a lower, muscle-back portion <NUM>, and a transition <NUM> between the upper portion <NUM> and the lower, muscle-back portion <NUM>. The upper portion <NUM> does not extend further rearward than the main body <NUM> top-rail <NUM>. The lower, muscle-back portion <NUM> does not extend further rearward than the main body <NUM> sole <NUM>. The upper portion <NUM> comprises a first insert thickness. The lower, muscle-back portion <NUM> defines a second insert thickness. The second insert thickness may vary. The second insert thickness may have a maximum thickness between the sole portion of the perimeter sidewall <NUM> and the insert transition <NUM>. The second insert thickness is larger than the first insert thickness. The insert transition <NUM> comprises a thickness that transitions from the first insert thickness to the second insert thickness.

Referring to <FIG>, <FIG>, <FIG>, <FIG>, <FIG> and <FIG>, the lightweight component <NUM> comprises a locking flange <NUM> configured to be received within the locking groove <NUM> in the perimeter sidewall <NUM> of the back cavity <NUM>, providing a mechanical lock to retain the lightweight component <NUM> within the back cavity <NUM>. The lightweight component <NUM> encompasses a void <NUM> for retaining the CTP weight <NUM>, such that the void <NUM> aligns with the heel aperture <NUM> in the main body <NUM>. The aperture <NUM> in the main body <NUM> and the void <NUM> in the lightweight component <NUM> combine to receive the CTP weight <NUM>. (<FIG>) The void <NUM> can be within the lower, muscle-back portion <NUM> of the lightweight component <NUM>. No portion of void <NUM> is within the lightweight component <NUM> transition portion <NUM> or upper portion <NUM>.

Referring to <FIG>, and <FIG>, the lightweight component <NUM> can surround a void <NUM> aligned to the aperture <NUM> in the heel end <NUM> of the golf club head <NUM>. The void <NUM> has a length measured from the heel end <NUM> toward the toe end <NUM> parallel to the sole <NUM> and striking face <NUM> of the golf club head <NUM> along the CTP weight <NUM> groove axis. The void <NUM> has a diameter or cross-sectional width. The void <NUM> is open to the aperture <NUM> at the heel end <NUM> and closed towards the toe end <NUM> such that the void <NUM> does not extend entirely through the lightweight component <NUM>. In many embodiments, the void <NUM> can be a tapered cylinder with a cross-sectional shape complementary to the shape of the heel aperture <NUM> of the main body <NUM>. (<FIG>) The cross-sectional shape of the void <NUM> can be tapered, so the cross-section toward the toe-end <NUM> of the void <NUM> is smaller than the void <NUM> cross-section toward the main body <NUM> heel-end <NUM>.

The void <NUM> length can be in a range of <NUM> (<NUM> inches) to <NUM> (<NUM> inches). The void <NUM> length may be <NUM> (<NUM> inches), <NUM> (<NUM> inches), <NUM> (<NUM> inches), <NUM> (<NUM> inches), or <NUM> (<NUM> inches).

The void <NUM> diameter or cross-sectional width can be in a range of <NUM> (<NUM> inch) to <NUM> (<NUM> inch). The void <NUM> diameter or cross-sectional width may be <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM> (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> inch).

Referring to <FIG>, the void <NUM> defines a void central axis <NUM>. The void central axis <NUM> is aligned with an aperture central axis. The void central axis <NUM> is parallel to a CTP groove axis <NUM>. The void central axis <NUM> can be parallel with the golf club head strikeface <NUM>. The void central axis <NUM> also directly aligns with the aperture <NUM> central axis. The void central axis <NUM> and aperture <NUM> central axis align because the void <NUM> aligns with the aperture <NUM> to receive the CTP weight <NUM> without any turns or hindrance into the void <NUM>.

Alternately, the void central axis <NUM> may form a -<NUM> degree to +<NUM> degree angle with the golf club head strikeface <NUM>; wherein a negative angle indicates that a toe ward portion of the void central axis <NUM> is angled toward the golf club head strikeface <NUM>, and a positive angle indicates that a toeward portion of the void central axis <NUM> is angled away from the golf club head strikeface <NUM>.

Still referring to <FIG>, the void central axis <NUM> defines a void angle <NUM> with the ground plane <NUM> when the golf club is at an address position. The angle <NUM> may be in a range of <NUM> degrees to <NUM> degrees.

Still referring to <FIG>, the void central axis angle <NUM> relative to the ground plane <NUM> when the golf club is at address may be <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> degrees.

Still referring to <FIG>, the void central axis angle <NUM> angles toward the top-rail <NUM> and toe end <NUM> of the golf club head <NUM>. The void <NUM> is configured to receive the CTP weight <NUM>. When the CTP weight <NUM> is received within the void <NUM>, the CTP weight <NUM> also angles toward the top-rail <NUM> and toe end <NUM> of the golf club head <NUM> so the weight toe end portion <NUM> is proximate the top-rail <NUM> and toe end <NUM> of the golf club head <NUM> because the orientation of the CTP weight <NUM> is determined by the orientation of the void <NUM>.

The lightweight component <NUM> may comprise a metallic alloy having a second density that is less than the first density of the main body <NUM> of the iron-type golf club head <NUM>. Alternately, the lightweight component <NUM> may comprise a thermoset or thermoplastic material. In still another embodiment, the lightweight component <NUM> may be formed of die casting or squeeze casting alloys such as an aluminum, manganese, magnesium, tin, or zinc alloy.

<FIG> all refer to a single embodiment of the golf club head <NUM>. All numbered features are the golf club head <NUM> features.

The CTP weight <NUM> may add additional mass for the final swing-weight of the assembled club. The CTP weight <NUM> is positioned in the void <NUM> of the lightweight component <NUM>. The CTP weight comprises a size and shape complementary to the void <NUM>. The CTP weight <NUM> may be a tapered cylinder or some other tapered shape.

The CTP weight <NUM> can comprise steel alloys, titanium alloys, aluminum alloys, plastic polymers, carbon fibers, composites, thermoplastic composites, or any other suitable material.

The CTP weight <NUM> can comprise a mass between <NUM> and <NUM>. The CTP weight <NUM> may have a mass of <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> grams.

The CTP weight <NUM> can be securely attached in the void <NUM> by adhesives, epoxy, welding, brazing, or any other suitable joining method. Alternately, the CTP weight may be press fit within the void <NUM> without the use of any permanent attachment method. In the alternate case, a first CTP weight <NUM> is interchangeable with another CTP weight or weights <NUM>. The alternate CTP weight or weights <NUM> may have mass properties and material compositions different from the first CTP weight <NUM>. A stopper or cap <NUM> is utilized to aesthetically cover the CTP weight <NUM> and to provide an additional mechanical lock to the CTP weight <NUM> (<FIG>). Alternately, the stopper or cap <NUM> may be the primary means of retaining the CTP weight <NUM> within the void <NUM>. In some embodiments, the stopper or cap <NUM> can be adhesively secured. In other embodiments, the stopper or cap <NUM> can be secured by any other attachment means such as threads, rivets, press-fit, etc..

In some embodiments, the CTP weight <NUM> can be comprised of at least two materials so the first CTP weight <NUM> material has a density less than the second CTP weight <NUM> material. The CTP weight <NUM> may have a center portion <NUM>, a heel end portion <NUM>, and a toe end portion <NUM>. Either the CTP weight <NUM> toe end portion <NUM> or heel end portion <NUM> can comprise the second CTP weight <NUM> material. The higher density material at either the CTP weight <NUM> heel end or toe end shifts the golf club head center of gravity toward the golf club head heel end <NUM> or toe end <NUM>.

In each embodiment, the golf club head comprises a main body with a back cavity. In each embodiment, a lightweight back cavity component, which further comprises an internal void, is placed within the back cavity. After placing the lightweight component into the back cavity, a CTP weight is placed within the lightweight component internal void through an aperture in the main body heel portion. A cap or stopper is then used to close the heel aperture and retain the CTP within the lightweight component void.

In one embodiment, the lightweight back cavity component may be press-fit in a back cavity by a forging operation to both fill the back cavity of the golf club head, and to appear a more traditional muscle back golf club head. In another embodiment, the lightweight back cavity component may be die-cast into the back cavity. In a third embodiment, the lightweight back cavity component may be injection molded from a polymer in one or more components and attached in the back cavity with an adhesive. Alternately, the lightweight back cavity component may be injection molded from a polymer directly into the back cavity. In each embodiment, the final golf club head further comprises.

In one embodiment the method of forming the golf club head <NUM>, the forging process utilizes an upper die, a lower die, and a pull rod <NUM>.

The upper die comprises the negative shape of the lightweight component <NUM>. The lower die comprises the negative shape of the main body <NUM> front. The pull rod <NUM> is sized to fit through the aperture <NUM> in the heel of the main body <NUM> and into the back cavity <NUM> (<FIG>). The pull rod <NUM> forms the size and shape of the void <NUM> in the lightweight component <NUM>. The main body <NUM> may also have a CTP weight <NUM> groove in the lower portion of the rear cavity.

In this embodiment, using 3D forging beneficially enables a lightweight component <NUM> to be securely fastened to a golf club <NUM> main body <NUM> with a void <NUM> for placing a CTP weight <NUM>. In typical forging applications, the final geometry of a part is very simplistic due to the limitations of the forging process, which would not allow for a void <NUM> to be produced. If a void <NUM> was desired in a typical forging application, a post-processing step such as machining would have to be used. Using the 3D forging process to create the void <NUM> is more cost-efficient than these alternative methods of producing the same feature. Using the lightweight component <NUM> can also enable inertia and center of gravity improvements for improved golf club <NUM> performance while maintaining an aesthetically pleasing muscle-back iron appearance.

Referring to <FIG>, in one embodiment the forging process for the lightweight component <NUM> comprises providing an upper, and lower forging die, wherein the upper die is configured to both receive the back portion of the main club body, and compress a billet of lightweight material to shape the muscle-back, lightweight back cavity insert; and wherein the lower die is configured to receive the main body strikeface down, placing the main body <NUM> into the lower forging die, orienting the back cavity <NUM> away from the lower forging die. (Referring to <FIG>) Placing the lightweight billet <NUM> into the back cavity of the main body <NUM>. Inserting the pull rod <NUM> through the aperture <NUM> in the heel of the main body <NUM> under the billet <NUM> and resting the pull rod <NUM> in the CTP groove <NUM>, preventing the lightweight component <NUM> from filling the CTP groove <NUM> during the forging process. Placing the upper forging die over the back cavity <NUM> and billet <NUM>, flush to the lower forging die at the plane of contact <NUM>, compressing the lightweight billet <NUM>. Applying heat and pressure during the forging/forming process to the part to deform the lightweight billet <NUM> to fill the back cavity <NUM> and locking groove <NUM> around the perimeter sidewall <NUM>. Removing the upper forging die, lower forging die, and pull rod <NUM>, wherein removing the pull rod <NUM> creates a void <NUM> in the lightweight component <NUM>. Assembling the golf club head <NUM> by inserting the CTP weight <NUM> through the aperture <NUM> into the void <NUM>, and thereafter sealing the aperture <NUM> with the cap or stopper <NUM>.

Referring to <FIG>, a method to use squeeze or die casting to create a second embodiment of the golf club head <NUM> comprises providing a die or mold configured to receive the golf club main body <NUM>; receiving the golf club main body <NUM> with the striking face <NUM> down and the main body <NUM> back cavity <NUM> exposed within the cavity of die or mold. Placing a pull rod <NUM> through the main body <NUM> heel aperture <NUM> resting in the sole <NUM> CTP groove <NUM> within the back cavity <NUM>. Placing the die or mold into a die-cast or squeeze-cast apparatus, injecting molten or plastic lightweight material to fill the back cavity <NUM>, shaping the lightweight insert component <NUM> within the back cavity <NUM>. Opening the die or mold and withdrawing the golf club head <NUM>, and then withdrawing the pull rod <NUM> out through the main body <NUM> heel aperture <NUM>, wherein a void <NUM> is left within the lightweight back cavity <NUM> insert <NUM> formed by the die-cast or squeeze cast operation. Assembling the golf club head <NUM> by inserting the CTP weight <NUM> through the aperture <NUM> into the void <NUM>, and thereafter sealing the aperture <NUM> with the cap or stopper <NUM>.

Referring to <FIG>, a method to use injection molding to create a third embodiment of the golf club head <NUM> comprises providing an injection mold configured to receive the golf club main body <NUM>; wherein injection mold is configured to receive the golf club main body <NUM> with the striking face <NUM> down and the main body <NUM> back cavity <NUM> exposed within a cavity of an injection mold. Placing a pull rod <NUM> through the main body <NUM> heel aperture <NUM> resting in the <NUM>CTP groove <NUM> within the back cavity <NUM>. Placing the injection mold into an injection molding apparatus, injecting polymeric, lightweight material to fill the back cavity <NUM> and shape the lightweight insert component <NUM> within the back cavity <NUM>, opening injection mold to withdraw the golf club head <NUM>, and then withdrawing the pull rod <NUM> out through the main body <NUM> heel aperture <NUM>, wherein a void <NUM> is left within the lightweight back cavity <NUM> insert <NUM> formed by the injection molding operation.

As the rules to golf may change from time to time (e.g., new regulations may be adopted, or old rules may be eliminated or modified by golf standard organizations and/or governing bodies such as the United States Golf Association (USGA), the Royal and Ancient Golf Club of St. Andrews (R&A), etc.), golf equipment related to the apparatus, methods, and articles of manufacture described herein may be conforming or non-conforming to the rules of golf at any particular time. Accordingly, golf equipment related to the apparatus, methods, and articles of manufacture described herein may be advertised, offered for sale, and/or sold as conforming or non-conforming golf equipment. The apparatus, methods, and articles of manufacture described herein are not limited in this regard.

Replacement of one or more claimed elements constitutes reconstruction and not repair. Additionally, benefits, other advantages, and solutions to problems have been described regarding specific embodiments. The benefits, advantages, solutions to problems, and any element or elements that may cause any benefit, advantage, or solution to occur or become more pronounced, however, are not to be construed as critical, required, or essential features or elements of any or all of the claims.

Claim 1:
An iron-type golf club head (<NUM>) comprising:
a main club body (<NUM>), an insert (<NUM>), a cap (<NUM>), and a weight (<NUM>);
wherein the main club body comprises:
a front, a rear, a toe end (<NUM>), a heel end (<NUM>), a strikeface (<NUM>), a strikeface front surface configured to impact a golf ball, a hosel configured to receive a golf shaft, a top-rail (<NUM>), a sole (<NUM>), a strikeface rear surface (<NUM>), and a perimeter sidewall (<NUM>) formed by the top rail, the sole, the toe end and the heel end;
wherein the perimeter sidewall extends rearwardly generally perpendicular to the strikeface;
wherein a back cavity (<NUM>) is defined by the perimeter sidewall and the strikeface rear surface; and
wherein the back cavity is open toward the rear of the main club body;
wherein the perimeter sidewall further comprises a locking groove (<NUM>) recessed into the perimeter sidewall at least partially surrounding the strikeface rear surface;
wherein the locking groove is recessed into the perimeter sidewall in a direction parallel to the strikeface rear surface offset rearwardly from the strikeface rear surface;
wherein the insert comprises:
an insert front surface, an insert rear portion, and an insert locking flange;
wherein the insert is configured to be received within the back cavity, and the insert locking flange is configured to be received within the locking groove;
wherein the insert front surface is configured to conform with and be directly adjacent to the strikeface rear surface;
wherein the insert rear portion further comprises an upper section, a muscle back portion, and a transition portion between the upper portion and the muscle back portion;
wherein the insert muscle back portion surrounds a void (<NUM>);
wherein the main club body further comprises an aperture (<NUM>) in the heel end such that the aperture is a hole open to a heel end outer surface and also open to the back cavity;
wherein when the insert is received within the back cavity, the aperture is aligned with the void;
wherein the weight is configured to be received within the void through the aperture;
wherein after the weight is received within the void, the aperture is sealed with the cap.