Golf Club Fitting Assembly

Abstract

This invention relates to golf club fitting devices and more particularly, to a novel golf club fitting assembly designed to interchangeably connect a shaft and club head.

Description

FIELD OF THE INVENTION

This invention relates to golf club fitting devices and more particularly, to a novel golf club fitting assembly designed to interchangeably connect a shaft and club head.

BACKGROUND

Various golf club fittings are known in the art to interchangeably connect a shaft and club head. Prior art attempts to propose a solution include devices and methods disclosed in US20070078026A1, US20060281575A1, US20050096148A1, U.S. Pat. No. 7,115,046, U.S. Pat. No. 7,083,529, U.S. Pat. No. 5,863,260, U.S. Pat. No. 7,144,332, U.S. Pat. No. 6,475,097, U.S. Pat. No. 5,452,890, WO9934882A1, US20050101401A1, U.S. Pat. No. 7,207,897, US20070117645A1, EP0634194A3, U.S. Pat. No. 6,890,269, U.S. Pat. No. 7,226,364, WO9524243A1, WO9944697A1, U.S. Pat. No. 5,624,330, U.S. Pat. No. 5,181,720, and US20040132540A1. The specification of each of these patents is incorporated by reference into this specification.

While some of these devices have gained popularity, they have not been successful in minimizing the impact upon playability of the golf club assembly and providing substantially the same feel and characteristics of a manufactured assembly of the same club head and shaft. Prior art devices have also not been successful in providing a truly universal golf club fitting that may be used with any manufacturer's club head or shaft, including irons, woods, putters, “rescue clubs,” drivers and the like, without altering shaft characteristics. The drawback of the prior art is that interchangeable golf fitting installation requires the shaft to be cut down and/or inserted into the club head. This loss of shaft length negatively affects the shaft characteristics.

It is desirable to design a golf club fitting that is close to the prior art golf club fittings, improving upon their functionality and eliminating one or more of their limitations. The present invention fulfills this need and others.

SUMMARY OF THE INVENTION

In accordance with this invention, there is provided an improved connection of a golf club head with a shaft that overcomes the limitations of the prior art by using a unique and previously unknown interchangeable golf club assembly comprising a shaft, a club head having a bore, a golf club fitting assembly interchangeably fixing the shaft to the club head, wherein the golf club fitting assembly comprises a tip, a screw-on ferrule and a sleeve, wherein the tip is fixed to the shaft with an adhesive material, the sleeve is fixed to the bore with an adhesive material, and the screw-on ferrule interchangeably fixes the tip to the sleeve, wherein the shaft is fully inserted into the bore of the club head.

There is also provided an interchangeable golf club fitting assembly comprising an interior coupling body, screw-on ferrule and a sleeve, wherein the interior coupling body comprises an interior cavity that receives a shaft and is fixed to the shaft with an adhesive material, the sleeve is fixed to a bore of a club head with an adhesive material and comprises a collar and an interior cavity that receives the interior coupling body, and the screw-on ferrule fixes the interior coupling body to the sleeve, thus interchangeably fixing the shaft to the club head, wherein axial rotation of the interior coupling body about the sleeve head is minimized by a gripping surface disposed on a bottom exterior peripheral surface of the interior coupling body.

There is also provided an interchangeable golf club fitting assembly comprising a tip, a compression fitting screw-on ferrule and a sleeve, wherein the tip is fixed to a shaft with an adhesive material, the sleeve is fixed to a bore of a club head with an adhesive material, and the compression fitting screw-on ferrule fixes the tip to the sleeve, thus interchangeably fixing the shaft to the club head, wherein axial rotation of the shaft about the club head is minimized by the compression fitting screw-on ferrule.

It is an object of this invention to provide an interchangeable golf club fitting assembly that minimizes the length of shaft that is decreased when mounted and connected to a club head.

It is a further object of the present invention to provide an interchangeable golf club fitting assembly where the “feel” of the interchangeable fitting substantially equals or compares to a standard manufactured golf club assembly.

It is a further object of the present invention to provide an interchangeable golf club fitting assembly that results in little or no impact on one or more of the following characteristics: club head speed, swing weight, shaft kickpoint and shaft flexibility.

It is a further object of the present invention to provide an interchangeable golf club fitting assembly that is mountable with minimum modification to the inside diameter of the hosel and/or club head.

It is a further object of the present invention to provide an interchangeable golf club fitting assembly that allows for full insertion of the actual shaft into the club head or hosel.

It is a further object of the present invention to provide an interchangeable golf club fitting assembly that may be used with hosels and hosel-less club heads of all playing club varieties.

It is a further object of the present invention to provide an interchangeable golf club fitting assembly that provides reinforcement stabilization by a combination of two or more of the following: a screw-on ferrule, ribs, serrations or grooves on the tip's spine, a stop-locking mechanism of the tip, and adhesive material.

It is a further object of the present invention to provide an interchangeable golf club fitting assembly that prevents overtorquing and mechanical failure of the threading on mechanical fasteners.

It is a further object of the present invention to provide an interchangeable golf club fitting assembly that is versatile and readily adaptable to different club heads and shafts.

It is a further object of the present invention to provide an interchangeable golf club fitting assembly that does not require a change in manufacturing technology or manufacturing tools for golf club shafts and club heads.

It is a further object of the present invention to provide a universal interchangeable golf club fitting assembly that does not alter the playability characteristics of the shaft or club head.

Whereas there may be many embodiments of the present invention, each embodiment may meet one or more of the foregoing recited objects in any combination. It is not intended that each embodiment will necessarily meet each objective.

Thus, having broadly outlined the more important features of the present invention in order that the detailed description thereof may be better understood, and that the present contribution to the art may be better appreciated, there are, of course, additional features of the present invention that will be described herein and will form a part of the subject matter of the claims appended to this specification.

In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The present invention is capable of other embodiments and of being practiced and carried out in various ways. Also it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described by reference to the specification and the drawings, in which like numerals refer to like elements, and wherein:

FIG. 1 is a perspective view of a golf club fitting assembly;

FIG. 2 is a perspective view of a golf club assembly including the golf club fitting assembly of FIG. 1;

FIG. 3 is a cross sectional side view of a golf club fitting assembly assembled for use;

FIG. 4 is a cross sectional side view of a golf club fitting assembly assembled for use;

FIG. 5 is an exploded cross sectional side view of a golf club assembly including the golf club fitting assembly of FIG. 1;

FIG. 6A is a cross sectional side view of a screw-on ferrule;

FIG. 6B is a perspective view of a screw-on ferrule depicted in FIG. 6A;

FIG. 6C is a perspective view of an alternate embodiment of a screw-on ferrule;

FIG. 6D is a side elevational view of an alternate embodiment of a screw-on ferrule depicted in FIG. 6C;

FIG. 7A is a side view of a tip and a shaft;

FIG. 7B is a side view of an alternate embodiment of a tip;

FIG. 7C is a side view of an alternate embodiment of a tip;

FIG. 7D is a side view of an alternate embodiment of a tip;

FIG. 7E is a side view of an alternate embodiment of a tip;

FIG. 8 is a cross sectional side view of a sleeve;

FIG. 9A is side elevational view of an alternate embodiment of a tip;

FIG. 9B is a cross sectional side view of an alternate embodiment of a sleeve;

FIG. 9C is a perspective cut-out view of the tip and sleeve depicted in FIGS. 9A and 9B;

FIG. 10A is a perspective view of an alternate embodiment of a golf club assembly including an alternate embodiment of the golf club fitting assembly;

FIG. 10B is a side elevational view of two components of the alternate embodiment of a golf club fitting assembly depicted in FIG. 10A; and

FIG. 10C is a cross sectional side view of the alternate embodiment of golf club fitting assembly depicted in FIG. 10A assembled for use.

The drawings are not to scale, in fact, some aspects have been emphasized for a better illustration and understanding of the written description.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

Definitions

As used in this specification, wood means a club meant to drive the ball a great distance down the fairway towards the hole, generally having a large head and a long shaft for maximum club speed. Originally made of wood, contemporary ‘woods’ are made from different metals, but called ‘woods’ to denote the general shape and their intended use on the golf course. Woods are also known in the golf industry as “driver”, “1 wood”, “fairway woods”, “utility woods,” and the like.

As used in this specification, Irons are golf clubs with a flat angled face and a shorter shaft than a wood, designed for shots approaching the green or from more difficult lies such as the rough, through or over trees, or the base of hills. Irons feature thin club heads and grooved faces and a relatively narrow sole, usually somewhere between 16° and 65°. Originally made from cast iron, contemporary irons are made of metal such as steel.

As used in this specification, driver means the number 1 wood.

As used in this specification, driving iron means a number 1 iron.

As used in this specification, pitching wedge means a short iron with a large degree of loft, used for pitching high but short shots onto the green.

As used in this specification, shaft means the part of the club that extends from all the way to the top of the club inside the grip to the club head.

As used in this specification, club head means the most massive part of the club at the bottom end (opposite the grip or handle) of the shaft, in other words, the part of the club that makes contact with the ball.

As used in this specification, sole means a bottom of the club. As used in this specification, ferrule means a decorative “cap” where the shaft inserts into the club head to make the transition from the head to the shaft smoother, more tapered or finished. Some clubs have ferrules, others are designed without them.

As used in this specification, hosel means the part of the club head into which the shaft is inserted. This is also known in the golf industry as the neck.

As used in this specification, kick point means the point of maximum bending of a club's shaft, measured with the club in a horizontal position by securing the grip end of the club and hanging a standardized weight just above the club head. This is also known in the golf industry as the flex point. This may be measured in any conventional manner, including according to the teachings of U.S. Pat. No. 5,018,735 to Meredith et al entitled “Low kick point golf club shaft.” The disclosure of said patent is incorporated herein by reference.

As used in this specification, torque means a force that produces, or tends to produce, torsion or rotation about an axis. It is a relative measure of how much twist there is in a club and the tendency of a club's shaft to twist or rotate around its long axis or the amount of that rotation measured in degrees.

As used in this specification, titanium means a titanium alloy with high strength-to-weight ratio, plus ability to withstand fatigue which provides great consistency.

Description of a Preferred Embodiment

FIG. 1 is a perspective view of a preferred embodiment of a novel golf club fitting assembly 10 of the present invention. Referring to FIG. 1, the golf club fitting assembly 10 comprises a screw-on ferrule 2, a tip 4 and a sleeve 6.

FIG. 2 depicts the golf club fitting assembly 10 as it would be installed in a golf club assembly 18 (club head 12, shaft 8 and golf club fitting assembly 10). Referring to the embodiment depicted in FIG. 2, a golf club assembly 18 is preferably assembled by inserting at least a part of the sleeve 6 into the internal hosel 14 of the club head 12 and securing the sleeve 6 therein using an adhesive such as epoxy. Preferably, the golf club assembly 18 is further assembled by inserting at least a part of the tip 4 into an internal cylindrical cavity 20 of the shaft 8 and securing the tip 4 therein using an adhesive such as epoxy.

Preferably, the golf club assembly 18 is further assembled by placing the screw-on ferrule 2 over the tip end 16 of the shaft 8. The tip end 16 of the shaft 8 is then inserted into the sleeve 6, which is mounted in the internal hosel 14 of the club head 12. The tip end 16 of the shaft 8 is inserted and rotated until the external threads 24 of the tip head 22 engage the internal threads of the sleeve 6 (not visible in this view but see 36 of FIG. 4). The screw-on ferrule 2 is slid over the external threads 30 of the sleeve's collar 26 protruding from the internal hosel 14 and then tightened onto sleeve 6, with the internal threads 32 of the screw-on ferrule 2 engaging the external threads 30 of the sleeve 6. The screw-on ferrule 2 compresses and constricts the fingers 34 of the sleeve 6, and the fingers 34 clamp around the circumference of the shaft 8. The fingers 34 cooperate to retain the shaft 8 in the sleeve 6 of the club head 12 and to restrict axial rotation of the shaft 8 within the sleeve 6 after the screw-on ferrule 2 is tightened onto the sleeve 6. As depicted more clearly in FIGS. 7B, 7C, 7D and 7E, ribs, serrations, bumps, dimples or grooves along the spine 52 of the tip 4 prevent further axial rotation of the tip 4 in the shaft's 8 internal cylindrical cavity 20.

It is to be understood that a club head 12 that may be used with the present invention may or may not have a hosel 14. Hosel-less club heads, as well as woods, irons and putters will work with the golf club fitting assembly 10 of the present invention. For simplicity in discussion, the present invention will be described as used with a hosel of a club head.

The sleeve 6 is also not limited to being a separate component which is assembled in the bore 15 (FIGS. 3, 5) of the golf club head 12. The present invention encompasses, among other embodiments, embodiments in which the sleeve 6 may be formed or fabricated as an integral component of the golf club head 12 or hosel 14.

The tip 4 is also not limited to being a separate component, which is assembled in the internal cylindrical cavity 20 (bore) of a shaft 8. The present invention encompasses, among other embodiments, embodiments in which the tip 4 may be formed or fabricated as an integral component of the golf club shaft 8. Similarly, in an alternate embodiment where the tip 4 is replaced with an interior coupling body (second sleeve) (see FIGS. 10A, 10B and 10C), the interior coupling body may be formed or fabricated as an integral component of the golf club shaft 8.

FIG. 3 depicts the configuration of the golf club fitting assembly 10 in use. The internal hosel 14 of a club head 12 receives the sleeve 6. The shaft 8 receives the tip 4 at tip end 16. The tip-shaft combination and the sleeve-hosel combination are then joined by the screw-on ferrule 2. The sleeve 6 is affixed in the hosel 14 with adhesive 5. The tip 4 is affixed in the shaft 8 with adhesive 7.

As shown in FIGS. 3, 4 and 5, the shaft 8 extends into the internal hosel 14. The length and weight of the resulting golf club assembly 18 is about the same as the identical club head 12 and shaft 8 combination with the shaft 8 fully inserted in and permanently attached to the hosel 14 of the club head 12, and thus, does not adversely alter the playability of either the club head 12 or shaft 8. Thus, golfers will get the feel of a standard production golf club of that club head 12 and shaft 8 combination.

The Bore in the Golf Club Head

Referring to FIG. 3, a conventional golf club head comprises a top surface 9, a bottom surface 11 and a heel end 13. Typically, a bore 15 is disposed in the heel end 13 of the golf club head 12, extending from the top surface 9 towards the bottom surface 11 of the golf club head 12. There may be provided a hosel 14 in some embodiments of a golf club head 12. Referring to FIGS. 3 and 4, the depth 17 of the bore 15 may extend any length into the golf club head 12 or the hosel 14, and variance is found in the prior art golf club heads 12 in this respect. The precise location and depth 17 of the bore 15, or the incorporation or absence of a hosel 14 or other extension from the golf club head 12, has no bearing on the utility of the present invention. A golf club head 12 that may be used with the present invention includes what have conventionally been referred to as irons, woods, putters, wedges, and the like. Indeed, one advantage of the present invention is that it can be used with most or all of the golf club heads 12 and shafts 8 of the prior art.

Referring to FIG. 5, the bore 15 in the golf club head 12 preferably has an inner surface 19 having an upper end 21 and a bottom end 23. The sleeve 6 preferably has an outer peripheral surface 25. At least a portion of the outer peripheral surface 25 of the sleeve 6 is, in one embodiment, inserted, or otherwise placed or formed, into the upper end 21 of the bore 15 of the golf club head 12.

The bore 15 of the golf club head 12 has a variable inner diameter 27 profile, including a minimum diameter sufficient to receive the sleeve 6. Typical bores have a diameter of from about 0.300 to 0.500 inch (about 0.762 to 1.27 centimeter).

The sleeve 6 is inserted into the bore 15 so as to extend through its central axis.

In one embodiment, bore 15 is hollowed to a diameter 27 of 0.40 inch (1.016 centimeters) to provide sufficient room for insertion of the sleeve 6.

Screw-on Ferrule

Referring to FIGS. 6A, 6B, 4, and 5, the screw-on ferrule 2 comprises a crown 38, a bore 41, a connecting section 40 and a body 42. When assembled, the shaft 8 and sleeve 6 are received within the bore 41 of the screw-on ferrule 2.

The bore 41 of the screw-on ferrule 2 has a variable inner diameter profile, including a minimum diameter 47 sufficient to receive the shaft 8. In one embodiment, the inner diameter is from about 0.300 to about 0.500 inch (about 0.762 to about 1.27 centimeter).

When the embodiment depicted is assembled for use, the crown 38 and the upper opening 43 of the bore 41 are positioned about the shaft 8 and the connecting section 40 is positioned about the external threads 30 (FIG. 5) of sleeve's 6, collar 26 protruding from the internal hosel 14. The connecting section 40 of the screw-on ferrule 2 is configured to cooperatively engage the external threads 30 of the sleeve's collar 26 such that the screw-on ferrule 2 is securely affixed to the sleeve 6 and, to that end, the screw-on ferrule 2 includes an annular ridge 45 adjacent to a lower opening 49 of the bore 41. Moreover, the connecting section 40 of the screw-on ferrule 2 and the sleeve's collar 26 are cooperatively configured to inhibit axial rotation of the screw-on ferrule 2.

Referring to FIGS. 6A, 6B, 3, 4 and 5, the connecting section 40 of the screw-on ferrule 2 and the collar 26 of the sleeve 6 cooperatively engage to inhibit rotation of the screw-on ferrule 2 about the sleeve 6. More particularly, the screw-on ferrule 2 further includes a plurality of grooves or threads 32 longitudinally aligned about the connecting section 40 and positioned above the annular ridge. The grooves or threads 32 are adapted to receive corresponding ribs or external threads 30 formed on the collar 26 of the sleeve 6. In this manner, the sleeve 6 and the screw-on ferrule 2 cooperate to inhibit axial rotation of the screw-on ferrule 2. In the exemplary embodiment, the grooves or threads 32 are positioned above the annular ridge. Other structural configurations can be employed to inhibit axial rotation of the screw-on ferrule 2. For example, the ribs 30 and corresponding grooves 32 can be positioned below or incorporated into the annular ridge, respectively. The threading configuration may be inversed such that the ribs are disposed on the connecting section 40 and the grooves are disposed of the collar 26 of the sleeve 6. A stop lock mechanism may be incorporated as well.

In one embodiment, the screw-on ferrule 2 has an inner diameter of from about 8.4 to about 9.3 millimeters (about 0.3307 to about 0.3661 inch) and an outside diameter of from about 12 to about 13.5 millimeters (about 0.4724 to about 0.5315 inch).

As the screw-on ferrule 2 is fastened onto the sleeve 6, the screw-on ferrule 2 constricts the fingers 34 (FIGS. 2, 8) of the sleeve 6 to clamp around the circumference of the shaft 8, thereby securing the shaft 8 in the club head 12.

The grooves 32 of the screw-on ferrule 2 extend a distance 48 which is more than the length of the ribs 30 of the collar 26 of the sleeve 6. The grooves 32 of the screw-on ferrule 2 extend a distance 48 of from about ⅛ inch (20.32 centimeters) to about ¾ inch (10.16 centimeters), preferably ⅜ inch (20.32 centimeters), increasing the compression and securing force of the two elements 2, 6 to one another. The screw-on ferrule 2 will compress and secure the shaft 8 to the sleeve 6 and club head 12. This extended grooved surface 32 creates more compression on the shaft 8 and ensures a secure attachment of the sleeve 6 and the screw-on ferrule 2.

In one embodiment, the screw-on ferrule body 42 is provided with an exterior surface that is smoothly tapered across its longitudinal length 46, providing an aesthetic and functional transition between the golf club head 12 and the shaft 8. The exterior surface can be provided with concave regions and/or raised regions to provide identifying indicia on the screw-on ferrule 2. In another embodiment, the exterior surface is provided with a plurality of flattened regions 50.

Referring to the embodiments depicted in FIGS. 6A, 6B, 6C and 6D, the exterior surface of the screw-on ferrule body preferably has two or more flattened portions 50 that allow a wrench or other tool to easily grasp the screw-on ferrule 2 during installation. The flattened portions 50 prevent slippage while the screw-on ferrule 2 is twisted tightly to secure the screw-on ferrule 2 to the sleeve 6.

The flattened portions may be larger as depicted in 50 of FIG. 6B such that a hex nut like feature is created. Alternatively, as depicted in FIGS. 6C and 6D, the flattened portions 50 may be only a portion of the exterior peripheral surface of the ferrule body 42. Preferably, the flattened portions 50 are disposed on opposing sides along the circumference of the body 42. In one preferred embodiment, there are at least four flattened portions 50 spaced equidistantly radially about the circumference of the body's 42 exterior surface.

Referring to FIG. 6A, the screw-on ferrule 2 is relatively short in order to minimally restrict the shaft 8 and allow for maximum playability. The length 46 of the screw-on-ferrule is about from about 0.25 inch (about 0.635 centimeter) to about 1 inch (about 2.54 centimeters). Preferably, the length 46 of the screw-on ferrule 2 is about 0.5 inches (about 1.27 centimeters). In another embodiment, the length of the screw-on ferrule 2 is from about 15 to about 30 millimeters (about 0.5906 to about 1.181 inch).

In conventional golf clubs, ferrules provide an ornamental function, but also serve as a protective member to alleviate stress on the shaft 8. The crown 38 of the screw-on ferrule 2 is formed with a slight curve or contour at it position of engagement with the shaft 8 to prevent possible breakage which may result from stress between the shaft 8 and crown 38 during use. The angle of the curve is not critical but can be selected to accomplish the purpose of minimizing stress, preventing vibration and/or absorbing shock at this juncture, in particular, that caused when the club head 12 contacts a golf ball during play.

In contrast to conventional ferrules having crisp angles at the ferrule corners, the crown 38 of the screw-on ferrule 2 preferably is chamfered or rounded along its exterior surface about the upper opening 43 of the bore 41 to prevent interference with the shaft 8 when assembled for use. It preferably has a natural 0.25 inch (0.635 centimeter) radius curve 44. This rounded crown 38 reduces shaft 8 damage caused by the mechanical stress at the moment when the club head 12, swung by a player, contacts a golf ball during play, or alternatively, contacts the ground during a miss-hit.

The Tip

Referring to FIGS. 7A, 7B, 7C 7D and 7E, the tip 4 is a screw-like and shaped member comprising a tip head 22, spine 52 and shoulder 54. The tip 4 functions as a mechanical fastener. The shoulder 54 (see FIG. 7A) may form a substantially square angle, however, it preferably is rounded as depicted in FIGS. 7A, 7B, 7C 7D and 7E. The radius of curve is configured and adapted to provide a contacting engagement with the tip end 16 of the shaft 8. The rounded shoulder 54 provides additional strength at this structurally weak point of the tip 4. To mount the tip 4 on the tip end 16 of the shaft 8, the shaft 8 is preferably contoured, e.g. rounded or ground down, such that it provides a close fit to conform to the shoulder 54 of the tip 4. In this embodiment, the tip end 16 of the shaft 8 is reduced (by sanding or other means) and adapted to provide a contacting engagement with the shoulder 54 of the tip 4. Preferably, at least a portion of the shoulder 54 contacts the tip end 16 of the shaft, and even more preferably, at least 50% of the surfaces of each respective component 4, 54 is in contacting engagement 8, 16 when assembled for use.

In one embodiment described below with reference to FIGS. 9A, 9B and 9C, the tip 4 is substantially similar to a stop lock fastener. Once the tip 4 is twisted to a certain point, further rotational movement in one direction is mechanically impeded by the mechanical locking device to prevent over-tightening. As will be apparent to those skilled in the art, many mechanical locking devices and arrangements may be suitably adapted to satisfy the intended function of this structural component.

One drawback of the prior art is overtorquing of the shaft 8 and mechanical failure of the threading on various threaded mechanical fasteners. With reverse threading, each square hit of the club head 12 will further tighten a screw or other threaded mechanical fastener, causing overtorquing and mechanical failure. By way of illustration, this problem was commonly encountered with the CLUB CONNEX® design. When the club head 12 was hit on its heel 13, the club head 12 loosed from the shaft 8. Additionally, the instructions required the user to loosen the shaft 8 after each ten or so golf hits to prevent this overtorquing and breakage. This requirement is undesirable for several reasons: first, it often required an inconvenient and costly trip to the pro shop, (2) it inconveniently occurred during play when the tools and facilities were not available, and (3) it required the user to keep a log or otherwise remember how many times each club was used during play.

A stop locking tip 4 (described below with reference to FIGS. 9A, 9B and 9C) eliminates this maintenance concern for the user and decreases incidents of breakage. Additionally, mechanically impeding further rotational movement in one direction preserves the structural relationship between the tip 4 and shaft 8 (or sleeve 6) during play, an essential feature to approval of the golf club assembly 18 by the USGA for tournament play.

Referring again to FIGS. 7B, 7C, 7D and 7E, the spine 52 preferably has protruding ribs, serrations and/or depressed grooves 51 extending across the exterior surface. In one aspect of this embodiment, the protruding ribs, serrations and/or depressed grooves 51 extend diametrically across the exterior surface of the spine 52. Alternatively or additionally, random or patterned dimples 53 along the surface area of the spine 52 may be provided. Preferably, the ribs, grooves, dimples or serrations 51, 53, are disposed on at least a part of the spine 52, but preferably not less than about 3%, not less than about 5%, not less than about 10%, not less than about 20%, not less than about 25%, and not less than about 50%, not less than about 75% of the surface area of the spine 52. These ribs, serrations, dimples or grooves 51, 53 facilitate a secure connection between the tip 4 and the shaft 8 by adding a friction surface element to prevent rotational movement (e.g. twisting) and/or a textured surface for better adhesion of the adhesive material.

As illustrated in various aspects depicted in FIGS. 7B, 7C, 7D and 7E, these ribs, serrations or grooves 51 may be horizontal or vertical (in relation to the spine 52), or preferably, a combination of horizontal and vertical (FIG. 7C). The ribs, serrations or grooves may also be diagonal (FIG. 7B), irregular and/or noncontinuous (FIG. 7D). In the embodiment depicted in FIG. 7B, these two sets of grooves 51 are essentially perpendicular to one another, thus forming diamond shapes between their intersections. In one embodiment, other patterns with protruding elements are used. In one embodiment, other patterns with depressed elements are used. The width, depth, shape, placement and number of grooves, ribs, serrations or dimples 51, 53 combine to increase the surface area for bonding.

Preferably, the width of the grooves, ribs or serrations 51 is equal or greater than their depth. Similarly, dimples 53 have a diameter that is equal or greater than their depth. In one embodiment, the depth of the ribs, grooves, serrations or dimples 51, 53 varies and is not uniform.

The diameter of the tip 4 including any protrusions on the surface of the spine 52, is slightly smaller than the inner diameter 68 (FIG. 8) of the sleeve 6, allowing for the tip 4 to be inserted in the sleeve's cavity 62 (FIG. 8) and threaded on the sleeve's internal threading 36 (FIG. 8).

Referring to FIG. 7A, a golf club assembly 18 is preferably assembled by inserting at least a part of the tip 4 into the internal cylindrical cavity 20 at the tip end 16 of the shaft 8 and securing the tip 4 therein using an adhesive such as epoxy. Preferably, at least a portion of the tip's shoulder 54 is in contacting engagement with the tip end 16 of the shaft 8 when assembled for use. In some embodiments, at least a portion of the tip's spine 52 is in contacting engagement with the shaft wall 31 when assembled for use.

The Sleeve

Referring to FIGS. 8, 1, and 2, the sleeve 6 comprises a collar 26, a sleeve cavity 62, and a sleeve wall 64. The sleeve's cavity 62 is adapted to receive a shaft 8. The sleeve 6 is adapted to be inserted inside the club head 12 or internal hosel 14 and the golf club fitting assembly 10 is preferably assembled by inserting at least a part of the sleeve 6 into the internal hosel 14 of the club head 12 and securing the sleeve 6 therein using an adhesive such as epoxy.

An adhesive material such as epoxy maybe used to secure the sleeve 6 to the shaft 8. The sleeve 6 is generally cylindrical and has both internal 36 and external 30 threading elements. The internal threading 36 is disposed at the lower portion 28 of the sleeve cavity 62 and the external 30 threading is disposed on the peripheral surface of the collar 26. The sleeve 6 is adapted to secure the tip head 22 of the tip 4 and the shaft 8 to one another. Internal threading 36 of the lower portion 28 of the sleeve 6 mates with external threading 24 on the tip head 22.

The lower portion 28 of the sleeve 6 preferably has a narrowed and threaded portion 36, or a cup, socket, or other cavity into which the tip end 16 of the shaft (with tip 4) is seated. The narrowed and threaded portion 36 serves to align the shaft 8 in the bore 15 (FIGS. 3, 5), and, by relationship, the golf club head 12. While the narrowed and threaded portion 36 is not essential to the invention, if used, it will provide greater consistency in the uniform location of the shaft 8, and axis thereof, from assembled golf club to golf club, as well as a more secure connection between the tip 4 and the sleeve 6.

In one embodiment, the sleeve 6 has a circular cross-sectional shape;

however, the present invention is not so limited. Rather, the peripheral shape of the sleeve 6 may take any shape or form. The sleeve preferably has a cylindrical cavity 62 extending therethrough, with a narrowed and threaded portion 36, or a cup, socket, or other cavity at the lower portion 28 into which the tip end 16 of the shaft 8 (with tip 4) is seated. The shape of the cylindrical cavity 62 through the sleeve 6 is not limited to having a uniform diameter, rather, the cylindrical cavity 62 will preferably have a shape which closely approximates the shape of the corresponding portion of the tip end 16 of the shaft 8 and tip 4 which will be positioned in the sleeve 6 when the golf club assembly 18 is assembled.

Referring again to FIGS. 5 and 8, the sleeve 6, if a separate component, preferably has an outer peripheral surface 25 of the sleeve wall 64 that generally conforms to the shape of at least a portion of the inner surface 19 of the bore 15. In one preferred embodiment, at least a portion of the outer peripheral surface 25 of the sleeve 6 is secured in the inner surface 19 of the upper end 21 of the bore 15 of the golf club head 12. As will be appreciated by those of ordinary skill in the art, any number of products or methods may be used to secure the sleeve within the upper end 21 of the bore 15, including, for example, adhesives, pins, keys, and interlocking mechanisms. Alternatively, the outer peripheral surface 25 of the sleeve 6 can form an interference fit with the corresponding upper end 21 of the bore 15 when assembled, or of sufficiently close tolerance to preclude the sleeve 6 from shifting relative thereto.

In one preferred embodiment, when assembled, the sleeve 6 includes a collar 26 (FIG. 5, 8) that extends upwardly from the golf club head 12 or internal hosel 14 and a lower portion 28 that is inserted into the bore 15. As will be appreciated by those of ordinary skill in the art, if present, the mating screw-on ferrule 2 can provide a more aesthetically pleasing and consistent transition between the golf club head 12 and shaft 8.

As discussed herein and referring to FIG. 5 and FIG. 8, the sleeve 6 preferably has a cylindrical cavity 62 therein, having an axis 72, through which the tip end 16 of the shaft 8 is inserted. The diameter 68 or other shape of the cylindrical cavity 62 in the sleeve 6 is preferably either an interference fit with the corresponding diameter or shape of the portion of the shaft 8 which as adjacent thereto when assembled, or of sufficiently close tolerance to preclude the shaft 8 from shifting relative thereto. In a preferred embodiment, there is a space between the outer peripheral surface 25 of the sleeve 6 and the inner surface 19 of the bore 15 that facilitates a flow of adhesive between the sleeve 6 and bore 15, thereby promoting a secure and durable bond amongst these components 6, 12. During assembly, excess adhesive can flow out an upper end 21 opening of the bore 15, as needed. Thereafter, excess adhesive can simply be wiped off.

The dimensions of the sleeve 6 are determined by the size of the club head 12, the length of the bore 15, and the diameter of the shaft 8. In one embodiment, the sleeve 6 has a length of about 1 inch (about 2.54 centimeters) to about 4 inches (about 10.16 centimeters) from the base of lower portion 28 to the base of collar 26 of sleeve 6, and the collar 26 has a length of from about 0.125 inch (about 0.3175 centimeter) to about 0.75 inch (about 1.905 centimeters) preferably about 0.5 inches (about 1.27 centimeters) in its uncompressed state. In this embodiment, the outer diameter 66 of sleeve 6 is about 0.400 inches (about 1.016 centimeters) and the inner diameter 68 is about from about 0.335 inch (about 0.8509 centimeter) to about 0.375 inch (about 0.9525 centimeter). The opening in the collar 26 fingers is about from about 0.335 inch (about 0.8509 centimeter) to about 0.375 inch (about 0.9525 centimeter).

The cylindrical cavity 62 of the sleeve 6 has a variable inner diameter 68 profile, including a minimum diameter sufficient to receive the tip-shaft 4, 8 assembly. In one aspect of the invention, the minimum diameter 68 is from about 0.335 inch (about 0.8509 centimeter) to about 0.400 inch (about 1.016 centimeters). In another aspect, the minimum diameter 68 is from about 0.200 inch (about 0.508 centimeter) to about 0.600 inch (about 1.524 centimeters).

In embodiments where the club head 12 has no hosel 14, the sleeve 6 is dimensioned to fit the tip end 16 of the shaft 8 while inserted in the bore 15 opening formed in the neck of the club head 12.

Thin sleeve walls 64 (FIG. 8) are necessary to allow the sleeve 6, shaft 8 and hosel 14 or club head 12 to be mated in an assembly, and to allow sufficient room for an adhesive material to be inserted between the external portion of the shaft 8 and the internal walls of sleeve 6. The sleeve wall 64 preferably has a thickness 70 of from about 0.010 to about 0.030 inches (about 0.0254 to about 0.0762 centimeter) such that the outer diameter 66 of the sleeve 6 is not more than about 0.050 inch (about 0.127 centimeter) greater than the outer diameter of the shaft 8.

Referring to FIGS. 5, 6A, 6B, and 8, the collar 26 of the sleeve 6 is generally cylindrical and has external threading 30. The external threading 30 is adapted to receive a screw-on ferrule 2. When the sleeve 6 is inserted into the club head 12, the external threading 30 of the sleeve's collar 26 will be fully exposed above the hosel 14. The external threading 30 extends a distance of from about 0.125 inches (about 0.3175 centimeter) to about 0.5 inches (about 1.27 centimeters), less than the length 48 of the internal threading 32 of the connecting portion 40 of the screw-on ferrule 2.

Referring to FIG. 8, the collar 26 of the sleeve 6 preferably has a plurality of slits 60 formed therein. Each slit 60 preferably extends along the collar 26 a length 75 of from about 0.25 to about 0.75 inches (about 0.635 to about 1.905 centimeter) and divides collar 26 into a plurality of fingers 34. In a preferred embodiment, the length 75 of each slit 60 is greater than the length 74 of the collar's 26 exterior threaded elements 30 by about 0.25 inch (about 0.635 centimeter). The collar 26 preferably includes at least three fingers 34 separated by three slits 60. The fingers 34 are flexible and compress when the screw-on ferrule 2 is fully fastened on the external threads 30 of the sleeve's collar 26.

In one embodiment (see FIGS. 10A, 10B and 10C), the sleeve's external lower portion 228 has a conical end that tapers inwardly to a point.

In one embodiment, the sleeve further comprises a stop ring (see 77 of FIG. 8). The stop ring's 77 function is to provide the installer or fitter with information (“easy, no guess” method) as to when the sleeve 6 insertion is complete, that is, how much of the sleeve's 6 length should be inserted into the bore 15 and how much of the sleeve 6 should be exposed. As previously discussed, there are various depths and configurations of bores 15, and thus, this provides for both a uniform and optimum installation across all club heads 12.

The stop ring 77 provides additional benefits in that it is a positive stop for the screw-on ferrule 2 and a gasket to prevent leakage of adhesive during installation. Referring to FIG. 8, the stop ring 77 is disposed below the collar and is formed as a protruding ring around the circumference of the sleeve 6. The protrusion should be no more than about 0.1181 inches (about 0.3 centimeter), preferably 0.01969-0.07874 inch (0.05001-0.2 centimeter). The stop ring 77 is also not limited to being an integral component; rather it may be a separate component which is assembled with the sleeve 6 prior to insertion in the bore 15 of the golf club head 12.

In one embodiment, the sleeve 6 further comprises a glue stop point indicator 79 (FIG. 8). The glue stop point indicator 79 may be an indent line, a scored line, an acid etched line or any other visual indicator manufactured integrally with or applied to the exterior peripheral surface of the sleeve 6. The function is to provide the installer or fitter with information as to where adhesive should preferably be applied to the sleeve 6 to prevent expulsion of excess upon insertion of the sleeve 6 in the hosel 14 or club head 12.

In one embodiment, the sleeve's collar further comprises shaft holding grooves 55 (FIG. 8) on the interior peripheral surface of its bore. These shaft holding grooves 55 facilitate a secure connection between the sleeve 6 and the shaft 8 by adding a friction surface element to prevent rotational movement (e.g. twisting) and/or a textured surface for better adhesion of the adhesive material. In a preferred embodiment, these shaft holding grooves 55 comprise very fine vertical and horizontal grooves that function to securely hold the shaft 8 in place without scratching it. Preferably, the width of the shaft holding grooves 55 is equal or greater than their depth. In one preferred embodiment, the depth of the shaft holding grooves 55 is 0.03937 inch (0.1 centimeter). In one embodiment, the depth of the shaft holding grooves 55 varies and is not uniform.

These shaft holding grooves 55 may be horizontal or vertical, or preferably, a combination of horizontal and vertical. They may also be diagonal, irregular and/or noncontinuous. These two sets of grooves may be essentially perpendicular to one another, thus forming diamond shapes between their intersections. In one embodiment, other patterns with protruding elements are used. In one embodiment, other patterns with depressed elements are used. The width, depth, shape, placement and number of shaft holding grooves 55 combine to increase the surface area for bonding.

As will be appreciated, these shaft holding grooves 55 may take many forms to accomplish the intended purpose, such as, for example, protruding ribs, serrations and/or depressed grooves extending diametrically across the interior peripheral surface of the collar. Alternatively or additionally, random or patterned dimples may be provided. Preferably, the ribs, grooves, dimples or serrations are disposed on at least a part of the interior peripheral surface of the collar, but preferably not less than about 3%, not less than about 5%, not less than about 10%, not less than about 20%, not less than about 25%, and not less than about 50%, not less than about 75% of the surface area.

In yet another embodiment, the sleeve's collar further comprises shaft gripping strips (not depicted) on the interior peripheral surface of its bore. These shaft gripping strips facilitate a secure connection between the sleeve 6 and the shaft 8 by adding a friction surface element to prevent rotational movement (e.g. twisting). In one preferred embodiment, the depth of the shaft gripping strips is about 0.03937 inch (about 0.1 centimeter). The shaft gripping strips are also not limited to being an integral component, rather they may be one or more separate components which are assembled with the sleeve 6 prior to insertion in the bore 15 of the golf club head 12.

Sleeve and Interior Coupling Body

In an alternate embodiment depicted in FIGS. 10A, 10B and 10C, a novel golf fitting assembly 200 comprises a screw-on ferrule 2, a sleeve 206, and an interior coupling body 204. Referring to FIG. 10A, the sleeve 206 is substantially the same as depicted and described with respect to sleeve 6 (see FIG. 2 and the like) with two exceptions: first, the collar 247 on the upper portion 226, and second, the internal lower portion 228 of the sleeve 206 (see 28 of FIG. 2). Referring to FIGS. 10B and 10C, in this alternate embodiment of the sleeve 206, the lower portion 228 of the sleeve 206 has a gripping surface 280 in the interior cavity that mates with a gripping surface 243 on the bottom peripheral surface of the interior coupling body 204. These mating gripping surfaces 280, 243 may comprise ribs, grooves, teeth or other friction elements suitable to prevent axial rotation. The gripping surfaces 280, 243 may be manufactured as an integral component or as a separate component and assembled to form sleeve 206 and interior coupling body 204. Referring again to FIGS. 8, 10A and 10B, the collar 247 of the sleeve 206 does not contain slits (see 60 of FIG. 8) in the threaded portions 230 (FIG. 10A).

As will be more fully described below, this embodiment 200 also differs in that the tip 4 element has been replaced with the interior coupling body 204 element.

In this embodiment 200, a golf club assembly is preferably assembled by inserting at least a part of the shaft 8 into the cavity of the interior coupling body 204. Thus, the interior cavity's diameter is slightly larger than the exterior diameter of the shaft 8. In one embodiment, the shaft 8 is secured inside the cavity of the interior coupling body 204 by an adhesive 282 (FIG. 10C) such as epoxy. Next, at least a part of the sleeve 206 is inserted into the bore of the internal hosel 14 of the club head 12 and secured therein using an adhesive 284 (FIG. 10C) such as epoxy. Then, at least a part of the shaft-interior coupling body assembly is inserted into the internal cavity of the sleeve 206 that has been mounted in the club head 12. The collar 247 of the sleeve 206 and the stop ring 245 of the interior coupling body 204 are in contacting engagement and aligned to receive the screw-on ferrule 2. When the screw-on ferrule 2 is screwed onto the collar 247 and stop ring 245, it securely affixes the shaft-interior coupling body assembly to the sleeve-club head assembly, thus creating a complete golf club fitting assembly. The golf club fitting assembly 200 has a length 300 (see FIG. 10C) from the bottom of the sleeve 206 to the top of the screw-on ferrule 2.

Preferably, in this embodiment 200 of the sleeve 206 that couples with the interior coupling body 204 (see FIG. 10B), the combined length of the collar 247 and the stop ring 245 is about the same as the length of the collar on the embodiment of the sleeve 6 that couples with the tip 4, from about 0.125 inch (about 0.3175 centimeter) to about 0.75 inch (about 1.905 centimeters) preferably about 0.5 inches (about 1.27 centimeters). The stop ring 245 of the interior coupling body 204 functions as a physical impediment and indicator that the interior coupling body 204 is fully seated within sleeve 206. It has no threading, its exterior diameter 256 (see FIG. 10B) is about 0.1875 inch (about 0.4762 centimeter) greater than the exterior diameter of the sleeve and its thickness 259 is only about 0.0625 inch (about 0.1588 centimeter) to about 0.125 inch (about 0.3175 centimeter).

The interior coupling body 204 has substantially the same profile as the sleeve 206 such that the interior coupling body 204 snugly mates with the sleeve 206. Thus, the exterior diameter of the interior coupling body 204 wall is slightly less than the diameter of the sleeve's 206 interior cavity. The length 276 of sleeve 206 is from about 1 inch (about 2.54 centimeters) to about 4.5 inches (about 11.43 centimeters). The length 266 of interior coupling body 204 is from about 1.0625 inch (about 2.699 centimeters) to about 4.625 inches (about 11.75 centimeters).

An adhesive material 282 such as epoxy is used to secure the interior coupling body 204 to the shaft 8. The interior coupling body 204 is generally cylindrical and receives the shaft 8 in its internal cavity. The interior coupling body 204 is adapted to secure the shaft 8 and the sleeve 206 to one another.

In one embodiment, the interior coupling body 204 has a circular cross-sectional shape; however, the present invention is not so limited. Rather, the peripheral shape of the interior coupling body 204 may take any shape or form. The interior coupling body 204 preferably has a cylindrical cavity or bore extending therethrough. The shape of the cylindrical cavity or bore through the interior coupling body 204 is not limited to having a uniform diameter, rather, the cylindrical cavity or bore will preferably have a shape which closely approximates the shape of the corresponding portion of the tip end 16 of the shaft 8 which will be positioned in the interior coupling body 204 when the golf club assembly is assembled.

Referring again to FIGS. 10A, 10B and 10C, the interior coupling body 204 preferably has an outer peripheral surface wall that generally conforms to the shape of at least a portion of the inner surface of the sleeve 206 cavity. In one preferred embodiment, at least a portion of the outer peripheral surface of the interior coupling body 204 is secured in the inner surface of the sleeve 206 cavity. As will be appreciated by those of ordinary skill in the art, any number of products or methods may be used to secure the interior coupling body 204 within the sleeve 206, including, for example, compression fit, friction fit, adhesives, pins, keys, and interlocking mechanisms. Alternatively, the outer peripheral surface of the interior coupling body 204 can form an interference fit with the corresponding interior cavity of the sleeve 206 when assembled, or of sufficiently close tolerance to preclude the interior coupling body 204 from shifting relative thereto.

In a preferred embodiment, the exterior peripheral surfaces of the sleeve 206 and interior coupling body 204 further comprises securing grooves 231 on the interior peripheral surface of its bore. These securing grooves 231 facilitate a secure connection between the sleeve 206 and the bore of the hosel or club head, and the interior coupling body 204 and sleeve 206, by adding a friction surface element to prevent rotational movement (e.g. twisting) and/or a textured surface for better adhesion of the adhesive material. In a preferred embodiment, these securing grooves 231 comprise very fine vertical and horizontal grooves that function to securely hold the elements in place without scratching. The securing grooves 231 can, but are not required, to be the same type and style on each the interior coupling body 204 and sleeve 206.

Preferably, the width of the securing grooves 231 is equal or greater than their depth. In one preferred embodiment, the depth of the securing grooves 231 is 0.03937 inch (0.1 centimeter). In one embodiment, the depth of the securing grooves 231 varies and is not uniform.

These securing grooves 231 may be horizontal or vertical, or preferably, a combination of horizontal and vertical. They may also be diagonal, irregular and/or noncontinuous. These two sets of grooves may be essentially perpendicular to one another, thus forming diamond shapes between their intersections. In one embodiment, other patterns with protruding elements are used. In one embodiment, other patterns with depressed elements are used. The width, depth, shape, placement and number of securing grooves 231 combine to increase the surface area for bonding.

As will be appreciated, these securing grooves 231 may take many forms to accomplish the intended purpose, such as, for example, protruding ribs, serrations and/or depressed grooves extending diametrically across the interior peripheral surface of the collar. Alternatively or additionally, random or patterned dimples may be provided. Preferably, the ribs, grooves, dimples or serrations are disposed on at least a part of the interior peripheral surface, but preferably not less than about 3%, not less than about 5%, not less than about 10%, not less than about 20%, not less than about 25%, and not less than about 50%, not less than about 75% of the surface area.

In one preferred embodiment, when assembled, the interior coupling body 204 includes an interior coupling body stop ring 245 that extends upwardly from the sleeve 206 and a lower portion that is inserted into the sleeve's 206 interior cavity. In a preferred embodiment, there is provided gripping surface 243 on the bottom peripheral surface of the interior coupling body 204 comprising ribs, grooves, teeth or other friction elements suitable to prevent axial rotation when seated in the sleeve 206.

As discussed herein, the interior coupling body 204 preferably has a cylindrical cavity therein, having an axis through which the tip end 16 of the shaft 8 is inserted. The diameter or other shape of the cylindrical cavity in the interior coupling body 204 is preferably either an interference fit with the corresponding diameter or shape of the portion of the shaft 8 which in inserted therein, or of sufficiently close tolerance to preclude the shaft 8 from shifting relative thereto. In a preferred embodiment, there is a space between the interior peripheral surface of the interior coupling body 204 cavity and the tip end of the shaft that facilitates a flow of adhesive between the interior coupling body 204 and shaft 8, thereby promoting a secure and durable bond amongst these components. During assembly, excess adhesive can flow out an upper end opening of the interior coupling body 204 as needed. Thereafter, excess adhesive can simply be wiped off.

The dimensions of the interior coupling body 204 are determined by the size of the sleeve 206, the length of the sleeve bore, and the diameter of the shaft 8. In one embodiment, the interior coupling body 204 has a length of about 1 inch (about 2.54 centimeters) to about 4 inches (about 10.16 centimeters) to the base of the interior coupling body stop ring.

In this embodiment, the outer diameter of the interior coupling body 204 is about from about 0.330 inch (about 0.8382 centimeter) to about 0.370 inch (about 0.9398 centimeter) and the inner diameter is about from about 0.28 inch (about 0.7112 centimeter) to about 0.36.

The cylindrical cavity of the interior coupling body 204 has a variable inner diameter profile, including a minimum diameter sufficient to receive the tip end of the shaft 8. In one aspect of the invention, the minimum diameter is from about from about 0.2 inch (about 0.508 centimeter) to about 0.38.

Thin interior coupling body 204 walls are necessary to allow the interior coupling body 204, shaft 8 and hosel 14 or club head 12 to be mated in an assembly, and to allow sufficient room for an adhesive material to be inserted between the external portion of the shaft 8 and the internal walls of interior coupling body 204. The interior coupling body 204 wall preferably has a thickness of from about 0.010 to about 0.030 inch (about 0.0254 to about 0.0762 centimeter) such that the outer diameter of the interior coupling body 204 is not more than about 0.1875 inch (about 0.4762 centimeter) greater than the outer diameter of the shaft 8.

The interior coupling body's stop ring 204 is generally cylindrical. When the interior coupling body 204 is inserted into the sleeve 206, the stop ring will be fully exposed above the collar of the sleeve 206 but will be in contacting engagement with their interface 278.

Stop Lock Tip and Sleeve

In another embodiment depicted in FIGS. 9A, 9B and 9C, the sleeve 106 and the tip 104 are secured with a stop lock mechanism. In this embodiment, a golf club assembly is preferably assembled by inserting at least a part of the sleeve 106 into the bore of the internal hosel 14 of the club head 12 and secured therein using an adhesive such as epoxy. Next, at least a part of the tip 104 is inserted into the internal cylindrical cavity 144 of the sleeve 106 that has been mounted in the club head 12. Thus, the interior cavity's 144 diameter is slightly larger than the exterior diameter 128 of the tip head 110. The head 110 of the tip 104 is inserted into the sleeve 106 and depressed 140 (FIG. 9C) such that the protuberances 108 align with and pass through the channels 116 in the lower portion 142 of the sleeve's 106 internal cylindrical cavity 144 and the tip head 110 comes in contacting engagement with spring 118. The tip head 110 is then rotated 122 (FIG. 9C) until the protuberances 108 come into contacting engagement with the notches 112, also disposed in the lower portion of the sleeve's internal cylindrical cavity 144, thereby securing the tip head 110 and preventing further axial rotation. Spring 118 exerts an upward force 146 to secure the protuberances 108 in the notches 112 and prevent vertical movement and dislodging. The collar 148 of the sleeve 106 is aligned to receive a screw-on ferrule 2 (see, for example, FIGS. 1, 2, 6A, 6B, 6C and 6D). When the screw-on ferrule 2 is screwed onto the collar 148, it compresses the respective fingers to securely affix the shaft-tip assembly to the sleeve-club head assembly, thus creating a complete golf club assembly.

As apparent, tip 104 is substantially the same as depicted and described with respect to tip 4 (see, for example, FIGS. 1-5 and 7A-7E). Thus, the characteristics of spine 138 (see FIG. 9C) and shoulder 136 may, but are not required to, include those depicted and described with respect to FIGS. 7A, 7B, 7C, 7D and 7E. The primary difference with this embodiment of the tip is in the tip head 110 (see FIGS. 9A, 9B and 9C). In particular, in lieu of threaded elements in FIGS. 1-5 and 7A-7E, the tip head 110 of this embodiment contains stop lock components.

Referring to FIG. 9A, the head 110 of the tip 104 contains a plurality of protuberances 108 along the exterior peripheral circumference. Preferably, the protuberances 108 are equally spaced about the tip head 110. While the number of protuberances 108 may vary in different embodiments, in the embodiment depicted, there are two protuberances 108. In another embodiment, there are four protuberances 108. In one embodiment depicted, the protuberances 108 are round with a diameter of from about 0.0011 to about 0.1200 inch (about 0.002794 to about 0.3048 centimeter). In one embodiment, the protuberances 108 protrude from the peripheral surface of the tip head 110 a distance 130 of from about 0.0011 to about 0.0787 inch (about 0.002794 to about 0.1999 centimeter).

As apparent, sleeve 106 is substantially the same as depicted and described with respect to sleeve 6 (see, for example, FIGS. 1-5) with the exception of the lower portion 142, in particular, the profile of the sleeve's internal cylindrical cavity is modified in the lower portion 142. For ease of manufacturing, access to the sleeve's lower 142 interior cavity 144 may be desirable. To accomplish this, the sleeve 106 may be manufactured as an integral unit, or alternatively, sleeve 106 may be manufactured as one or more separate components and assembled together to form a sleeve 106. By way of illustration, bottom wall 120 may be manufactured as a separate component to allow machining of the internal cylindrical cavity 144 of the lower portion 142 of sleeve 106 and a means for easily inserting spring 118. By way of illustration, raised portion 114 may be manufactured as a separate component.

Referring to FIGS. 9B and 9C, the lower portion 142 of the sleeve's internal cylindrical cavity 144 contains a plurality of channels 116 that are sized, aligned and configured to allow passage of the protuberances 108 on the tip head 110. Referring to FIGS. 9B and 9C, the channels 116 have a length 124 of from about 0.01969 to about 0.1969 inch (about 0.05001 to about 0.5001 centimeter) and a width 134 of from about 0.001969 to about 0.1181 inch (about 0.005001 to about 0.3 centimeter). The number and location of channels 116 will correspond to the number and location of protuberances 108 on the tip head 110. Preferably, the channels 116 are equally spaced about the interior circumference of the sleeve wall 150. In one embodiment, the channels 116 are spaced at a distance 132 apart of from about 0.03937 to about 0.3937 inch (about 0.1 to about 1 centimeter). While the number of channels 116 may vary in different embodiments, in the embodiment depicted, there are two channels 116. In another embodiment, there are four channels 116.

The lower portion 142 of the sleeve's internal cylindrical cavity 144 also contains a plurality of notches 112 sized, aligned, and configured to receive and secure the protuberances 108 on the tip head 110 therein, thereby preventing further axial rotation. The number and location of notches 112 will correspond to the number and location of protuberances 108 on the tip head 110. Preferably, the notches 112 are equally spaced about the interior circumference of the sleeve wall 150. Preferably, the notches 112 are disposed between the channels 116 and equally spaced therebetween. While the number of notches 112 may vary in different embodiments, in the embodiment depicted, there are two notches 112. In another embodiment, there are four notches 112.

The lower portion 142 of the sleeve's internal cylindrical cavity 144 contains at least one spring 118, preferably a conical spring to reduce solid height, which comes in contacting engagement with the tip head 110 and exerts an upward force 146 to secure the protuberances 108 in the notches 112 and prevent vertical movement and dislodging. Spring 118 is affixed to the bottom wall 120 and has a height 126 of from about 0.01969 to about 0.1969 inch (about 0.05001 to about 0.5001 centimeter) when uncompressed.

As will be appreciated, this embodiment is intended to be illustrative and nonlimiting, and that many stop lock mechanisms may suitably be adapted to accomplish the intended function and are to be regarded as included within the scope of the present invention.

Materials and Manufacturing

The golf club fitting assembly 10 may be formed of a rigid metal or plastic. By way of illustration, but not limitation, steel, carbon steel, soft iron, an aluminum alloy, aluminum bronze, stainless steel, brass, aluminum or fiber reinforced plastic may be used. Preferably however, the golf club fitting assembly 10 is formed of titanium or a titanium alloy. It may also be formed of high strength aluminum, stainless steel or other high strength metals and metal alloys.

In one embodiment, tip 4, screw-on ferrule 2 and sleeve 6 are preferably composed of the same lightweight titanium material.

The present invention is manufactured according to any method known to, or devised by, one skilled in the art for the manufacture of golf clubs and components and/or golf club fittings.

Advantages and Improvements over the Prior Art

One improvement of the present invention over the prior art is that the golf club fitting assembly comprises any combination of at least two of four reinforcement stabilizers: screw-on ferrule 2 exerting compression, the ribs, grooves, dimples or serrations 51, 53 on the tip's spine 52 (see FIGS. 7B, 7C, 7D, and 7E), external threading (grooves) 24 on the tip head (screw-like member) 22 and the adhesive material. These reinforcement stabilizers minimze rotational movement of the club head about the shaft. This allows for superior stability and minimized opportunity for shaft 8 movement once installed.

In prior art fitting systems, adhesive is the primary means of bonding, and thus, the bond strength is dependent upon the adhesive material strength and the size of the bonding area. Applicant's golf club fitting assembly 10 relies on more than an adhesive material to affix the shaft 8 to the club head 12. First, the textured surface of the tip's spine 52 (e.g., grooves, ribs, serrations 51, dimples 53) increases the surface area and mechanical connection. Second, the increased length 48 of the threading 32 on the screw-on ferrule 2 (see FIGS. 6A and 6B) increases the mechanical connection. Third, the compression fitting of the screw-on ferrule 2 with the sleeve's collar 26 increases the mechanical connection. This combination works in concert to restrict and prevent rotation of the club head during use.

One drawback of the prior art interchangeable fittings is that the playability of the golf club is compromised. When the interchangeable golf club fitting is mounted, a portion of the shaft length is decreased. This in turn affects the kickpoint of the shaft 8 and the user's “feel” of the golf club assembly 18 during use. The present invention greatly minimizes the premounting length of shaft 8 that is decreased when mounted in the golf club assembly 18. In one embodiment, the premounting length of shaft 8 decrease is less than about 1.5 inches (about 3.81 centimeters), less than about 1.25 inches (about 3.175 centimeters), less than about 1.0 inches (about 2.54 centimeters), less than about 0.75 inches (about 1.905 centimeters), less than about 0.5 inches (about 1.27 centimeters) and less than about 0.25 inches (about 0.635 centimeter). In this manner, the “feel” of the interchangeable golf club fitting assembly 10 substantially compares to a standard manufactured golf club assembly.

The length of a club is one of the most important determining factors of club head 12 speed, and is measured from the back of the heel 13 (see FIG. 3) to the top of the grip cap. Other specifications that work in conjunction with the length to determine the club head 12 speed are shaft flex and the sole radius. Changing the length of a club has an effect on other parameters of the golf club as well. As an illustration, if the club is made shorter, it becomes less upright during use, the swing weight becomes lighter, and the less flexible it becomes.

The kickpoint is the point in the shaft 8 where the degree of bending is greatest. It determines the ball's launch angle. A lower kickpoint creates more loft because the “kick” is nearer the club head 12. Kickpoint has a direct bearing on trajectory and as a result determines how easy a club is to hit, or at least the golfer's perception of the ease or difficulty factor. Ball flight is affected by the location of the kickpoint. A high kickpoint may help lower the trajectory of most golfers' shots. A low kickpoint may result in a slightly higher trajectory for most golfers.

Kick point measurements are mostly made directly from the bend shape adopted by the shaft 8 in a simple cantilever bend test. A popular approach is to draw an imaginary line between the butt and tip end 16 of the shaft 8 and locate the point along its length where the kick is furthest from this imaginary line. This is defined as the bend point and is measured as so many inches or millimeters from the tip end 16 of the shaft 8. The kick point is generally always found in the bottom third of the shaft toward the tip end 16.

Whereas the length of the shaft is only nominally modified, the present invention does not, or only nominally, offsets (e.g. relocates) the kickpoint in either longitudinal direction along the shaft. In one aspect, the kickpoint is offset by less than about 0.01 to about 1.5 inches (about 0.0254 to about 3.81 centimeter). Thus, the playability of the component parts is maintained.

Better players need less help from the shaft 8. They create their own club head speed 12 and kick and generally use shafts 8 with higher kickpoints. Mid-to-high handicappers, seniors and women need more help getting the ball airborne so a lower kickpoint is to their advantage. Also, better players with smooth, flowing swings may benefit from softer shafts with lower kickpoints. Physically strong players, who swing very hard, even if they aren't low handicappers, are often best fitted with stronger shafts 8.

The relative stiffness or flex dictates the amount of bend within a given shaft 8 pattern, and is dependent upon the thickness of the shaft walls 31 (see FIG. 7A) and the step arrangement in steel shafts. The flexibility of the shaft 8 needs to closely match the club head 12 speed that the player is generating during the swing. Flexes are normally manufactured in five categories: Ladies (L), Amateur (A) sometimes also referred to as “senior flex”, Regular (R), Stiff (S), and Extra Stiff (X).

Swing weight is the measurement of a golf club's weight distribution about a fulcrum point which is established at a 14 inches (35.56 centimeters) from the grip end of the club. An increase in swing weight will increase club head 12 speed and lightening the swing weight will reduce the club head 12 speed. Preferably, no matter which club the player takes out of the bag, they should be able to swing at the ball and get the same reaction from the head at impact throughout the whole set.

Whereas the length of the shaft 8 is nominally decreased when using the golf club fitting assembly 10 of the present invention, the kickpoint remains substantially true to the design of the particular shaft and is not inadvertently lowered or raised by installing the golf club fitting assembly 10. Similarly, swing weight, club head 12 speed and shaft 8 flexibility parameters are preserved, thus playability is not impacted.

Swing weight is not impacted because the hollowing out of the bore to 0.40 inch (1.016 centimeters) removes weight that is substantially the same weight as added by the sleeve.

One drawback of the prior art interchangeable fittings (e.g. those by TAYLORMADE® and CALLAWAY®) is that the inside diameter 27 (see FIG. 5) of the bore 15 of the hosel 14 or club head 12 is modified to enable mounting. Once the inside diameter 27 is modified, the characteristics of the club head 12 and its playability or “feel” in a golf club assembly 18 are changed.

In one aspect, the weight of the club head 12 is changed by less than about 1 %, by less than about 3%, by less than about 5%, and by less than about 10%, when the bore is configured to be affixed to the sleeve. Also in contrast, the present invention requires nominal or no boring for installation and use. In one aspect, when the bore is configured to be affixed to the sleeve, the diameter of the bore is changed by less than about 1%. In another aspect, the diameter of the bore is changed by less than about 5%.

Additionally, this modification renders the club heads 12 unusable after modification since they can no longer be used with other fittings, shaft connectors or shafts 8. The structural integrity of a USGA approved club head 12 renders it unusable for tournament play after reassembly with another shaft 8. In contrast, the present invention may be removed and the club head 12 may once again be used with conventional fitting systems and traditional fitting methods.

The only prior art that comes close to this characteristic is the CLUB CONNEX® design, however that design has the following drawbacks: (1) it is susceptible to overtorquing and requires continual maintenance to prevent it, and (2) it flexes higher because the shaft must be reduced (cut off) for installation. Thus, the playability characteristics, especially shaft kickpoint, are adversely impacted by such design.

One improvement of the present invention over the prior art is that the golf club fitting assembly 10 allows for full insertion of the actual shaft 8 into the club head 12 or hosel 14. This reduces impact on the playability of the golf club assembly in that club head swing weight and shaft kickpoint remain as designed by the manufacturer or adjusted in a custom fitting.

One improvement of the present invention over the prior art is that the fitting is compatible with any club head 12 or hosel 14 design, including but not limited to 0.335, 0.350, 0.355, 0.370, “through bore,” “standard bore,” and “blind bore” configurations. With the exception of the CLUB CONNEX® product, prior art fitting systems are proprietary and work specifically with certain club heads 12, shafts 8 or fitting systems. The CLUB CONNEX® design is not commercially available. The present invention will fill this need in the art and can be used with irons, woods, putters, wedges, rescue clubs, drivers and the like.

As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the invention be regarded as including such equivalent construction insofar as they do not depart from the spirit and scope of the conception regarded as the present invention.

Claims

1. An interchangeable golf club assembly comprising

a shaft,

a club head having a bore,

a golf club fitting assembly interchangeably fixing the shaft to the club head, wherein the golf club fitting assembly comprises an interior coupling body, a screw-on ferrule and a sleeve, wherein

the interior coupling body comprises an interior cavity that receives the shaft and is fixed to the shaft with an adhesive material,

the sleeve is fixed to the bore of the club head with an adhesive material and comprises a collar and an interior cavity that receives the interior coupling body, and

the screw-on ferrule fixes the interior coupling body to the sleeve, thus interchangeably fixing the shaft to the club head, wherein axial rotation of the interior coupling body about the sleeve is minimized by a gripping surface disposed on a bottom exterior peripheral surface of the interior coupling body, and

wherein the shaft is fully inserted into the bore of the club head.

2. The interchangeable golf club fitting assembly of claim 1, wherein

the shaft has a pre-mounting length,

the premounting length is decreased by less than about 1.5 inches (about 3.81 centimeters) when the shaft is affixed to the club head with the golf club fitting assembly.

3. The interchangeable golf club assembly of claim 2, wherein the premounting length of the shaft is decreased by less than about 5 percent when the shaft is affixed to the club head with the golf club fitting assembly.

4. The interchangeable golf club of claim 2, wherein the shaft further comprises a kickpoint, and the kickpoint is offset by less than about 1 inch (about 2.54 centimeters) when the shaft is affixed to the club head with the golf club fitting assembly.

5. The interchangeable golf club assembly of claim 1, wherein the tip comprises a spine having a textured peripheral surface, and axial rotation of the shaft about the club head is minimized by the textured peripheral surface.

6. The interchangeable golf club assembly of claim 5, wherein the tip further comprises a head having external threading, the sleeve further comprises an internal cavity having threading and is configured to receive the head of the tip.

7. The interchangeable golf club assembly of claim 2, wherein the sleeve comprises an external diameter that is configured to be received by a bore having an internal diameter of from about 0.300 to about 0.500 inch (about 0.762 to about 1.27 centimeter).

8. The interchangeable golf club fitting assembly of claim 2, wherein the tip comprises a mechanical locking device to prevent movement of the tip in the sleeve.

9. The interchangeable golf club fitting assembly of claim 18, wherein

the sleeve is fixed to a bore of a club head having a premounting weight, and

wherein the premounting weight of the club head is changed by less than about 1 percent when the bore is configured for the sleeve to be fixed to the bore.

10. The interchangeable golf club fitting assembly of claim 18, wherein

the bore has an inner diameter of from about 0.300 to about 0.500 inch (about 0.762 to about 1.27 centimeter), and

wherein the inner diameter is changed by less than about 5 percent when the bore is configured for the sleeve to be fixed to the bore.

11. The interchangeable golf club fitting assembly of claim 18, wherein

the screw-on ferrule comprises a compression fitting screw-on ferrule, and

wherein axial rotation of the shaft about the club head is minimized by the compression fitting screw-on ferrule.

12. The interchangeable golf club fitting assembly of claim 11, wherein the compression fitting screw-on ferrule comprises an exterior surface having at least two flattened portions and wherein the at least two flattened portions are radially an equal distance from one another around the exterior surface.

13. The interchangeable golf club fitting assembly of claim 11, wherein the compression fitting screw on ferrule further comprises a crown having an exterior surface and a bore having an upper opening, wherein the crown is chamfered along the exterior surface about the upper opening.

14. The interchangeable golf club fitting assembly of claim 18, wherein the screw-on ferrule comprises a compression fitting screw-on ferrule further comprising a connecting portion having an internal threading, the internal threading having a length, and wherein the length of the internal threading is from about 0.125 inch (about 0.3175 centimeter) to about 0.5 inches (about 1.27 centimeters).

15. The interchangeable golf club fitting assembly of claim 18, wherein the sleeve further comprises an external threading having a length, wherein the screw-on ferrule comprises a compression fitting screw-on ferrule that mates with the external threading of the sleeve, and wherein the length of the external threading is less than about ⅜ inch (20.32 centimeters).

16. The interchangeable golf club fitting assembly of claim 18, wherein

the sleeve further comprises a plurality of fingers, the screw-on ferrule comprises a,

compression fitting screw-on ferrule that compresses and constricts the plurality of fingers when affixed to the sleeve thereby causing the plurality of fingers to clamp around a circumference of the interior coupling body.

17. The interchangeable golf club fitting assembly of claim 16, wherein the plurality of fingers cooperate to restrict axial rotation of the shaft about the sleeve.

18. An interchangeable golf club fitting assembly comprising an interior coupling body, screw-on ferrule and a sleeve, wherein

the interior coupling body comprises an interior cavity that receives a shaft and is fixed to the shaft with an adhesive material,

the sleeve is fixed to a bore of a club head with an adhesive material and comprises a collar and an interior cavity that receives the interior coupling body, and

the screw-on ferrule fixes the interior coupling body to the sleeve, thus interchangeably fixing the shaft to the club head, wherein axial rotation of the interior coupling body about the sleeve is minimized by a gripping surface disposed on a bottom exterior peripheral surface of the interior coupling body.

19. The interchangeable golf club fitting assembly of claim 18, wherein the interior coupling body further comprises a stop ring that aligns with the collar of the sleeve to receive the screw-on ferrule.

20. The interchangeable golf club fitting assembly of claim 18, wherein rotational movement of the club head about the shaft is minimized by a combination of the adhesive material, a mechanical connection of the screw-on ferrule to the interior coupling body and sleeve, and the gripping surface.