EP2377584A1

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Publication number: EP2377584A1
Application number: EP11160473A
Authority: EP
Inventors: Joshua G. Breier; Charles E. Golden
Original assignee: Cobra Golf Inc
Current assignee: Cobra Golf Inc
Priority date: 2010-04-15
Filing date: 2011-03-30
Publication date: 2011-10-19
Also published as: CN102218208A; JP2011224367A; US20100261543A1

Abstract

Disclosed herein is a golf club including a shaft, a club head and several devices for releasably connecting the shaft to the club head.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part ofU.S. Patent Application No. 11/958,412, filed December 18, 2007, currently pending, which is a continuation-in-part ofU.S. Patent Application No. 11/734,819, filed April 13, 2007, abandoned, which are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

This invention generally relates to golf clubs, and more specifically to golf clubs having an improved hosel connection that provides interchangeability between a shaft and a club head.

BACKGROUND OF THE INVENTION

In order to improve their game, golfers often customize their equipment to fit their particular swing. In the absence of a convenient way to make shafts and club heads interchangeable, a store or a business offering custom fitting must either have a large number of clubs with specific characteristics, or must change a particular club using a complicated disassembly and reassembly process. If, for example, a golfer wants to try a golf club shaft with different flex characteristics, or use a club head with a different mass, center of gravity, or moment of inertia, in the past it has not been practical to make such changes. Golf equipment manufacturers have been increasing the variety of clubs available to golfers. For example, a particular model of golf club may be offered in several different loft angles and lie angles to suit a particular golfer's needs. In addition, golfers can choose shafts, whether metal or graphite, and adjust the length of the shaft to suit their swing. Recently, golf clubs have emerged that allow shaft and club head components, such as adjustable weights, to be interchanged to facilitate this customization process.

One example is U.S. Pat. No. 3,524,646 to Wheelerfor a Golf Club Assembly. The Wheeler patent discloses a putter having a grip and a putter head, both of which are detachable from a shaft. Fastening members, provided on the upper and lower ends of the shaft, have internal threads, which engage the external threads provided on both the lower end of the grip and the upper end of the putter head shank to secure these components to the shaft. The lower portion of the shaft further includes a flange, which contacts the upper end of the putter head shank, when the putter head is coupled to the shaft. This design produces an unaesthetic bulge at the top of the shaft and another unaesthetic bulge at the bottom of the shaft.
Another example isU.S. Pat. No. 4,943,059 to Morellfor a Golf Club Having Removable Head. The Morell patent discloses a putter golf club including a releasable golf club head and an elongated golf club shaft. The club head hosel has a plug containing a threaded axial bore. A threaded rod is retained on the connector portion of the shaft, and is threaded into the axial bore of the plug of the club head for operatively connecting the shaft to the head.
Another example isU.S. Pat. No. 5,433,442 to Walkerfor Golf Clubs with Quick Release Heads. The Walker patent discloses a golf club in which the club head is secured to the shaft by a coupling rod and a quick release pin. The upper end of the coupling rod has external threads that engage the internal threads formed in the lower portion of the shaft. The lower end of the coupling rod, which is inserted into the hosel of the club head, has diametric apertures that align with diametric apertures in the hosel to receive the quick release pin.
Another example isU.S. Pat. No. 5,722,901 to Barron et al. for a Releasable Fastening Structure for Trial Golf Club Shafts and Heads. The Barron patent discloses a bayonet-style releasable fastening structure for a golf club and shaft. The club head hosel has a fastening pin in its bore that extends diametrically. The head portion of the shaft has two opposing "U" or "J" shaped channels. The head end portion of shaft fastens on the hosel pin through axial and rotary motion. A spring in the hosel maintains this fastenable interconnection, but allows manually generated, axially inward hosel motion for quick assembly and disassembly.
Another example isU.S. Pat. No. 5,951,411 to Wood et al. for a Hosel Coupling Assembly and Method of Using Same. The Wood patent discloses a golf club including a club head, an interchangeable shaft, and a hosel with an anti-rotation device. The hosel contains an alignment member with an angular surface that is fixed, by a stud, within the hosel bore. A sleeve secured on the shaft end forms another alignment arrangement element and is adapted to engage the alignment element disposed in the hosel bore. A capture mechanism disposed on the shaft engages the hosel to fix releasably the shaft relative to the club head.
Another example isU.S. Publ. Pat. App. No. 2001/0007835 A1 to Baronfor a Modular Golf Club System and Method. The Baron publication discloses a modular golf club including club head, hosel, and shaft. A hosel is attached to a shaft and rotation is prevented rotation by complementary interacting surfaces, adhesive bonding or mechanical fit. The club head and shaft are removably joined together by a collet-type connection.
Another example isU.S. Pub. Pat. App. No. 2006/0105855 A1 to Cackett et al. for a Golf Club with Interchangeable Head-Shaft Connections. The Cackett publication discloses a golf club that uses a sleeve/tube arrangement instead of a traditional hosel to connect the interchangeable shaft to the club head in an effort to reduce material weight and provide for quick installation. A mechanical fastener (screw) entering the club head through the sole plate is used to secure the shaft to the club head.
Still another example isU.S. Pat. No. 6,547,673 to Roarkfor an Interchangeable Golf Club Head and Adjustable Handle System. The Roark patent discloses a golf club with a quick release for detaching a club head from a shaft. The quick release is a two-piece connector including a lower connector, which is secured to the hosel of the club head, and an upper connector, which is secured to the lower portion of the shaft. The upper connector has a pin and a ball catch that both protrude radially outward from the lower end of the upper connector. The upper end of the lower connector has a corresponding slot formed therein for receiving the upper connector pin, and a separate hole for receiving the ball catch. When the shaft is coupled to the club head, the lower connector hole retains the ball catch to secure the shaft to the club head.
Other published patent documents, such asU.S. Pat. No. 7,083,529 andU.S. Publ. Pat. App. Nos. 2006/0287125,2006/0293115,2006/0293116and2006/0281575, disclose interchangeable shafts and club heads with anti-rotation devices located therebetween.
There remains a need in the art for golf clubs with an improved connection that provides a method for quickly and easily interchanging the shaft, removable weights and other attachments with the club head.

SUMMARY OF THE INVENTION

The invention is directed to a releasable connection system for assembling a golf club. The inventive connection system provides interchangeability between a shaft and a club head that imparts minimal visual impairment and club mass fluctuation while optimizing customization.
In one embodiment, the present invention includes a connection system that comprises a two-part hosel, wherein a first hosel part is connected to the shaft and a second hosel part is connected to the club head, and an anti-rotation device is disposed between the first and second hosel parts, and the anti-rotation device is located above the club head. The anti-rotation device can have a first serrated surface disposed on the first hosel part and a second corresponding serrated surface disposed on the second hosel part. The first and second serrated surfaces mate to minimize relative rotation between the shaft and the club head.
In another embodiment, the connection system comprises a hollow sole insert affixed in a hosel bore proximate a sole of the club head, wherein a first key is disposed on an internally threaded distal end of the shaft and a second corresponding key is disposed on the sole insert. As a fastener is inserted through the sole insert and into the threaded distal end of the shaft to connect the shaft to the club head, the first and second keys mate with each other to minimize relative rotation between the shaft and the club head.
In another embodiment, the connection system comprises a spring loaded bayonet mount, wherein the spring has a spring constant from about 5 pounds-force/inch to about 100 pounds-force/inch and wherein the spring loaded bayonet mount is located above the club head. The bayonet mount comprises at least one post disposed on the shaft and at least one corresponding channel disposed on a hosel of the club head and the bayonet mount further comprises a spring disposed within the hosel. The channel may have a reduced diameter section sized and dimensioned to releasably retain said post. Alternatively, the bayonet mount comprises two or more posts disposed on the shaft and two or more corresponding channels disposed on a hosel of the club head.
In another embodiment, the connection system comprises a hosel rotatable connection comprising a first hosel sheath, a second hosel part and an anti-rotation device. The first hosel sheath is connected to the shaft; the second hosel part is preferably made integral to the club head, and an anti-rotation device is disposed between the first and second hosel parts, and the anti-rotation device is preferably located above the club head. The anti-rotation device can have a first serrated surface disposed on the first hosel sheath and a second corresponding serrated surface disposed on the second hosel part. The first and second serrated surfaces mate to minimize relative rotation between the shaft and the club head. The hosel sheath has distal internal threads that threadably mate with the external threads on the second hosel part connected to the club head to hide the anti-rotation device to preserve the esthetics of the club head. In another embodiment, the first rotatable hosel sheath is connected to the hosel.
In another embodiment, the connection system comprises two or more legs of uneven lengths connected to the shaft. One of the legs is an affixing leg and the other leg is a non-affixing leg. Corresponding receiving areas are provided in the hosel. The two or more legs cooperate to minimize relative rotation between the shaft and the club head. The affixing leg preferably is threaded to the hosel.
Preferably the threaded connections of the embodiments of the present invention comprise multiple parallel threads to maintain the thread count of the connection, thereby improving the strength of the connection, while minimizing the time required connecting the threaded connectors together.
In another embodiment, the connection system comprises a wedge hosel connected to the shaft, a club head insert disposed within the club head and a wedge screw threadedly connected to the wedge hosel through the heel of the club head to retain the wedge hosel to the club head and to the club head insert. The anti-rotation device comprises a first serrated surface disposed on the wedge hosel and a second corresponding serrated surface disposed on the club head insert. The wedge screw also minimizes club head rotation relative to the shaft.
In another embodiment, the connection system comprises a bendable hosel, club head insert, and anti-rotation device. The bendable hosel is connected to the shaft, and the shaft-hosel assembly is connected to the club head via a screw. The connection system further comprises a cap disposed below the screw head to retain the screw within the club head during connection and disconnection. An anti-rotation device is also provided.
A hosel insert adapted to change the loft and/or lie angle of the club is also provided. A dampener or spring can be placed within the connection system to minimize vibration during impacts.
In another embodiment, the anti-rotation device comprises first tapered projections operatively connected to the shaft and second tapered projections operatively connected to the club head, wherein the first and second tapered projections are sized and dimensioned so that when the shaft is connected to the club head a gap is formed between at least some of the tapered projections and the shaft or club head. This gap assists the two projections to fit flush together when assembled.
The inventive connection system may also comprise a threaded connection, wherein said threaded connection comprises a first threaded surface operatively connected to the shaft, a corresponding second threaded surface operatively connected to the club head and a helical coil insert adapted to fit between the first and second threaded surfaces.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, which form a part of the specification and are to be read in conjunction therewith and in which like reference numerals are used to indicate like parts in the various views:
FIG. 1 is an exploded view of an exemplary driver club showing a shaft, a club head and a first embodiment of the inventive connection system;
FIG. 2 is an exploded view of the two-part hosel of the connection system ofFIG. 1;
FIG. 3 is a perspective view of the assembled shaft;
FIG. 4 is a partial cross-sectional view of the connection system ofFIG. 1;
FIG. 5 is a perspective view of the assembled driver club ofFIG. 1;
FIGS. 6 and 7 are perspective views another embodiment of the inventive connection system;
FIG. 8 is an exploded view of an exemplary driver club and another embodiment of the inventive connection system;FIGS. 8A and8B are alternatives of the embodiment ofFIG. 8;
FIG. 9 is an exploded view of an alternative of the embodiment ofFIG. 8 illustrated with an iron club;
FIG. 10A is an exploded view of another embodiment of the inventive connection system;FIG.10B is a perspective view of the assembled club head, sheath, shaft, and inserts ofFIG.10A;FIG. 10C is an exploded view of inner shaft insert, sheath, and outer shaft insert ofFIG. 10A; andFIG. 10D is an exploded view of shaft inserts, sheath, and assembled shaft and club head ofFIG 10A;
FIG. 11A is an exploded view of another embodiment of the inventive connection system;FIG.11B is a perspective view of the assembled club head, reverse sheath, shaft and insert ofFIG.11A;FIG. 11C is an exploded view of shaft insert and shaft ofFIG.11A; andFIG. 11D is an exploded view of iron insert, reverse sheath, and club head ofFIG. 11A;
FIG. 12A is an exploded view of another embodiment of the inventive connection system;FIG.12B is a perspective view of shaft insert ofFIG 12A;FIG. 12C is a partial rear, exploded hosel and club head ofFIG. 12A;FIG. 12D is an exploded view of shaft and shaft insert ofFIG. 12A; andFIG. 12E is a partial cross-sectional view of assembled iron club ofFIG. 12A;
FIG. 13A is a force-flow through a set of threaded fasteners; andFIG. 13B is a single threaded right-hand and double threaded left-hand fastener;
FIG. 14A is a partial cross-sectional view of a club head adapted for use with another embodiment of the inventive connection system;FIG. 14B is an enlarged perspective view of a wedge hosel ofFIG. 14A; FIG. 14C is an exploded view of shaft and wedge hosel;FIG. 14D is a perspective view of assembled shaft and wedge hosel ofFIG. 14A; FIG. 14E is an enlarged perspective view of wedge screw; andFIG. 14F is a partial cross-sectional view of assembled club of this embodiment;FIG. 14G is a cross-sectional view of another embodiment of the wedge hosel;FIGS. 14 H-I are top views of alternatives of the head of the wedge shown inFIG. 14G; FIG. 14J is a cross-sectional view of an alternative of the body of the wedge shown inFIG. 14G;
FIG. 15A is a partial cross-sectional view of a club head for use with another embodiment of the inventive connection system;FIG. 15B is a perspective view of a bendable hosel;FIG. 15C is an exploded view of the shaft, bendable hosel and shaft insert;FIG. 15D is an exploded view showing the club head ofFIG. 15A and the assembled shaft and hosel ofFIG. 15C;
FIG. 16A is an exploded view ofFIG.15D with a system for retaining the screw in the club head;FIG. 16B is a partial cross-sectional view of the assembled golf club;FIG. 16C is an enlarged perspective view of one embodiment of the retaining system;FIG. 16D is an enlarged cross-sectional view of the club head bore adapted to receive the retainer ofFIG. 16C; and FIG. 16E is an enlarged perspective view of another embodiment of the retainer;
FIG. 17A is a partial cross-sectional view of a club head for use with another embodiment of the inventive connection system; andFIG.17B is a partial cross-sectional view of the assembled golf club with a translucent window;
FIG. 18A is a perspective view of a club head ofFIG. 5 with an hosel insert; andFIG. 18B is an enlarged view perspective view of the hosel insert;
FIGS. 19A-C are perspective views of an alternative to the anti-rotation feature of the present invention;FIG. 19D is a schematic view of another serrated anti-rotation surfaces; and
FIG. 20A is a cross-sectional view of another embodiment of the present invention;

FIGS. 20B-C are cross-sectional views of variations of the embodiment shown inFIG. 20A;
FIG. 20D is a cross-sectional view of a damper/spring usable with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is directed to a quick connection system for connecting the shaft to a club head and for changing the shaft or the club head to optimize the golfer's strength to the playing conditions. Such a system can be utilized or customized for various applications, including, but not limited, to the shaft-club head connection, the insertion of adjustable weights in the club head, and the connection of a sole plate to the club head. Several embodiments of the present invention are described below.
Inventive connection system 10 is designed for club fitters to repeatedly change shaft or club head combinations during a fitting session.Inventive connection system 10 is designed to give fitting accounts maximum fitting options with a system that is fast and easy to use.
Referring toFIGS. 1 and2,connection system 10 releasably connectsclub head 12 toshaft 14, such thatdifferent shafts 14 can be connected to different club heads 12.Connection system 10 comprises a two-part hosel,i.e., shaftserrated hosel 16 and driverserrated hosel 18 and internally threadedshaft insert 20.Serrated surface 17 ofshaft hosel 16 andserrated surface 19driver hosel 18 are sized to mate with each other to minimize or prevent relative rotation betweenshaft hosel 16 anddriver hosel 18. Preferably, each serrated surface comprises a plurality of corresponding teeth.Connection system 10 further comprises driversole insert 22 andscrew 24, which are connected toclub head 12 on the sole side, as shown.
As best shown inFIG. 3,shaft 14 is at least partially hollow and is sized and dimensioned to receive and retain internally threadedshaft insert 20 therewithin. Preferably,shaft insert 20 is securely attached toshaft 14 by means of adhesives, epoxies or similar materials. Shaftserrated hosel 16 is sized and dimensioned to fit on the outside ofshaft 14. Apredetermined length 26 ofshaft 14 is positioned below shaftserrated hosel 16 for insertion intoclub head 12. The internal threads ofshaft insert 20 are adapted to receive the external threads offastener 24, such asscrew 24.
As best shown inFIG. 4, driverserrated hosel 18 has external threads, as shown, and is threaded into the top ofbore 28 ofclub head 12. Adhesives or epoxies can also be used to affix driverserrated hosel 18 to bore 28. At the bottom ofbore 28, driversole insert 22 is inserted intobore 28 and affixed therein. Preferably, driversole insert 22 is serrated or threaded on the outside surface to increase the surface area to adhesives or epoxies. The assembledshaft 14 withshaft insert 20 andshaft hosel 16 as shown inFIG. 3 is inserted throughdriver hosel 18 and intobore 28.Screw 24 is inserted through driversole insert 22 and is threaded intoshaft insert 20 to secureshaft 14 toclub head 12. Preferably,distal tip 30 ofshaft 14 is spaced apart from the top of driversole insert 22 andshaft 14 and driversole insert 22 is separated bygap 32.Gap 32 ensures thatscrew 24 can fully pullshaft 14 downward toward the sole ofclub head 12 so thatserrated surfaces 17 and 19 fully engage each other to minimize relative rotation between the twohosels 16 and 18 thereby minimizing relative rotation betweenshaft 14 andclub head 12. In other words,gap 32 ensures thatscrew 24 does not "bottom out" inside threadedshaft insert 20 so thatserrated hosels 16 and 18 can fully mate with each other.
Optionally, bore 28 hasledge 34 shown inFIG. 4 formed integrally thereon, e.g., through the casting process, to abut driver sole insert 22 to provide additional structural support for driversole insert 22 andscrew 24. Alternatively, driver sole insert 22 can be formed integrally onbore 28. These alternatives are applicable to all of the embodiments described herein.
Referring toFIG. 5, a fully assembled golf club is shown.Serrated hosels 16 and 18 form a single hosel and theserrated lines 17 and 19 separating the two hosels are preferably located above the top ofclub head 12. The advantage of locating the anti-rotation device,i.e., shaftserrated hosel 16 and driverserrated hosel 18, above the club head is that no additional mass is added, thereby preserving the mass properties of the club head and eliminating a protrusion at the shaft/hosel intersection. The anti-rotation device uses a standard hosel to make both the shaft serrated hosel and the driver serrated hosel. This means there is no weight gained or lost from the device, which in turn means no change in moment of inertia or center of gravity. Furthermore,serrated lines 17 and 19 add a visual distinction to the golf club and readily identify the golf club as an interchangeable golf club.
Driver sole insert 22 and shaft threadedinsert 20, as well ashosel insert 16 and/orhosel insert 18, can be made out of aluminum, stainless steel or titanium.Screw 24 can be any threaded screw, and is preferably a TORX™ drive flat head screw and thesole insert 22 is tapered so that the head ofscrew 24 can be flushed withsole insert 22, as best shown inFIG. 4.
Referring toFIGS. 6 and 7, another embodiment ofconnection system 10 is shown. In this embodiment, the two-part hosel of the first embodiment is replaced by a keyed anti-rotation device. This keyed anti-rotation device comprises angled cut-out 36 on the distal tip ofshaft 14.Shaft 14 is also hollow and has threadedshaft insert 20 inserted therein andconventional hosel 40 disposed thereon. Driver sole insert 22' has angledsurface 38 sized and dimensioned to match cut-out 36. In this embodiment,shaft 14 is inserted into driver sole insert 22', and angled cut-out 36 is keyed to angledsurface 38 asscrew 24 is threaded intoshaft insert 20 to minimize or prevent relative rotation betweenshaft 14 and driver sole insert 22'/club head 12. An advantage of this embodiment is that an anti-rotation device can be added without adding substantial weight to the club head thereby minimizing the effect on the club's swing weight.
Referring toFIG. 8, another embodiment ofconnection system 10 is shown. In this embodiment, bore 28 does not extend throughclub head 12.Club head 12 hashosel 42, which has at least one and preferably two ormore channels 44.Channel 44 hasentry leg 46 and lockingleg 48.Leg 46 is adapted to receivepost 50 onshaft 14. Afterpost 50 travels throughentry leg 46, it passestransverse leg 47 before being received and held in lockingleg 48. Disposed withinhosel 42 isspring 52 that exerts an upward force onshaft 14 to hold securely post 50 in lockingleg 48.Spring 52 is selected so that it can exert a sufficient force to holdpost 50 withinchannel 44. Preferably,spring 52 has a spring constant from about 5 to about 100 pounds-force/inch. More preferably, the spring constant can be in the range of about 20 to about 75 pounds-force/inch and most preferably about 33 pounds-force/inch. A golfer can conveniently insertshaft 14 intohosel 42 after aligningpost 50 toleg 46. Thereafter,shaft 14 is rotated alongtransverse leg 47 and afterward spring 52 pushesshaft 14 up lockingleg 48.Post 50 andchannel 44 is also known as a bayonet mount or connection.
Althoughchannel 44 is illustrated as a "J-shaped" channel, it can have any shape,e.g., "U", "L", "S", "V" or "W" shape. Also, preferablyleg 46 is preferably deep so that aspost 50 is moved down intohosel 42, more ofshaft 14 overlaps hosel 42 to increase mechanical stability. Alternatively, the top of locking leg may have a reduced diameter section to holdpost 50 by press-fit or by increased friction. As illustrated inFIG. 8A, the reduced diameter section can be a triangular section. The reduced diameter section can also be a figure-eight or waist section.
In another embodiment, shown inFIG. 8B, the connection system provides adjustability of an angular attribute ofgolf club head 12 relative toshaft 14, such as face angle, loft and lie. Similar to previous embodiments,club head 12 includeshosel 42, but in the present embodiment,hosel 42 has at least twochannels 44 so that the shaft may be positioned in at least two discrete orientations relative tohead 12. For example,shaft 14 may be coupled tohosel 42 in a first orientation and in a second orientation in which the shaft is rotated about a longitudinal axis ofhosel 42 from the first orientation.Channels 44 are spaced circumferentially aroundhosel 42 and eachchannel 44 hasentry leg 46 and lockingleg 48.
Shaft 14 includes adistal engagement portion 43 and a proximal portion that extends from the distal portion to a grip end ofshaft 14. In an assembled golf club,engagement portion 43 is at least partially received inhosel 42 and coupled thereto. The engagement portion may comprise a separate sleeve component that is attached toshaft 14 or it may be formed as an integral part ofshaft 14 during the manufacture.Engagement portion 43 is a generally elongate portion ofshaft 14 that is shaped to engagehosel 42 and defines a longitudinal axis A. The engagement portion ofshaft 14 defines a longitudinal axis B that is angled relative to axis A by an angular offset θ. By providing at least two discrete orientations ofshaft 14 relative to head 12 and angular offset θ, an angular attribute ofclub head 12 relative toshaft 14 may be altered. Preferably, the angular offset θ ranges from about 0.5° to about 5.0°.
At least onepost 50 is included onengagement portion 43. Post 50extends radially outward from an outer surface ofengagement portion 43 and is configured to engagechannel 44. Preferably,shaft 14 includes the same number ofposts 50 aschannels 44. For example, in an embodiment that includes two channels circumferentially spaced about the hosel by 180° also, preferably includes two posts circumferentially spaced about the engagement portion by 180°. In the present embodiment, post 50 is a screw that engages a threaded bore inengagement portion 43 and is therefore movably coupled toengagement portion 43.
Inchannel 44,leg 46 is adapted to receivepost 50 onshaft 14. Afterpost 50 travels throughentry leg 46, it passestransverse leg 47 before being received and held in lockingleg 48. Disposed withinhosel 42 isspring 52 that exerts an upward force onshaft 14 to hold securely post 50 in lockingleg 48.Spring 52 is selected so that it can exert a sufficient force to holdpost 50 withinchannel 44. Additionally, the top of locking leg may include areceptacle 49 that receives a portion ofpost 50 to prevent relative motion betweenshaft 14 andclub head 12 whenpost 50 is fully engaged inchannel 44. For example, the screw may be configured to lock intoreceptacle 49 when the screw is tightened, such as by forming receptacle as a countersunk portion of lockingleg 48 and engaging it with a countersunk screw head.
FIG. 9 illustrates another variation of the embodiment ofFIG. 8, wherehosel 42 has two ormore channels 44.Channels 44 can have the shapes or configurations of those described inFIGS. 8 and8A. An advantage of this embodiment is that having two ormore locking legs 48 prevents twisting at the lower end of the leg and it offers a back up should one of the lockinglegs 48 fail.
Referring toFIGS. 10A to 10D, another embodiment ofconnection system 10 comprises a firstrotatable hosel sheath 70 with internal threads and a second threaded,hollow hosel part 72, which is fixedly attached toclub head 74. Preferably, second threadedhosel part 72 is made integral toclub head 74, andhosel sheath 70 andhosel part 72 are sized and dimensioned to threadably attach to each other to connectshaft 14 toclub head 74.Connection system 10 further comprises an anti-rotation device, made up of firstserrated surface 76 disposed oninner shaft insert 80 and corresponding secondserrated surface 78 disposed on second threadedhosel part 72.
To assemble the club,upper end 82 ofinner shaft insert 80 is inserted into the threaded end ofrotatable hosel sheath 70, as shown inFIG. 10C.End 82 is sized and dimensioned to pass throughaperture 84 ofhosel sheath 70, but the top portion ofserrated surface 76 is retained withinhosel sheath 70.End 82 is then inserted intoaperture 86 and finally attached toouter shaft insert 88. Afterend 82 ofinner shaft insert 80 is fixedly connected toouter shaft insert 88, there is sufficient clearance forfirst hosel sheath 70 to be freely rotatable to connect tosecond hosel part 72. Preferably, the length ofend 82 is dimensioned so that onceend 82 is fully inserted intoaperture 86, there remains sufficient clearance betweenouter shaft insert 88 andhosel sheath 70 forhosel sheath 70 to rotate freely.Outer shaft insert 88 is then inserted intoshaft 14. Alternatively,inner sheath insert 80 is inserted into and attached directly toshaft 14 andouter sheath insert 88 can be omitted.
Although this embodiment of the present invention is particularly suited tohosel sheath 70 made of metal,hosel sheath 70 can be made of high impact transparent or translucent materials. Suitable materials include, but are not limited to, polymethacrylate, cellulose acetate butyrate, polycarbonate (Lexan®), and glycol modified polyethylene teraphthalate.
Afterward, as shown inFIG. 10D,shaft 14, withdecorative ferrule 90,hosel sheath 70 and both shaft inserts 80 and 88, is assembled withclub head 74. More specifically,lower end 83 ofinner shaft 80 is inserted intosecond hosel part 72 to allow corresponding threads ofhosel sheath 70 andhosel part 72 to mate and connectshaft 14 toclub head 74.End 83 may extend partially or fully intoclub head 74.Serrated surfaces 76 and 78 also mate to minimize relative rotation between the shaft and the club head.
Referring toFIGS. 11A to 11D, another embodiment ofconnection system 10 comprises a rotatable hoselreverse sheath 92 with internal threads and a threaded,hollow shaft insert 94, which is fixedly attached toshaft 14. Hoselreverse sheath 92 andshaft insert 94 are sized and dimensioned to threadably attach to each other to connectshaft 14 toclub head 98.Connection system 10 further comprises an anti-rotation device, made up of firstserrated surface 100 disposed onclub insert 102 and corresponding secondserrated surface 104 disposed onshaft insert 94.
To assemble the club,upper end 96 ofshaft insert 94 is inserted into and fixedly connected toshaft 14 for example by adhesive or epoxy, as shown inFIG.11C. Preferably, the length ofend 96 is dimensioned so that there is a sufficient bond betweenshaft insert 94 andshaft 14.Threads 106 and secondserrated surface 104 should remain outside ofshaft 14 and next todecorative ferrule 108.
As shown inFIG.11D,lower end 110 ofclub insert 102 is inserted intoreverse sheath 92.End 110 is sized and dimensioned to pass throughaperture 112 ofreverse sheath 92, but the bottom portion ofserrated surface 100 is retained within rotatablereverse sheath 92.End 110 is then inserted intohosel 114 and is attached thereto.End 110 may extend partially or fully intoclub head 98 so long as there is sufficient clearance forreverse sheath 92 to rotate freely. To assemble the club, the assembled version ofFIG. 11C is inserted into the assembled version ofFIG. 11D.Serrated surfaces 100 and 104 mate to minimize relative rotation between the shaft and the club head andreverse hosel sheath 92 is rotated so that its internal threads mate withthreads 106 ofshaft insert 94 to connectclub head 98 toshaft 14.
Referring toFIGS. 12A to 12E, another embodiment ofconnection system 10 compriseshollow shaft insert 54 connectingshaft 14 toclub head 56.Shaft insert 54 comprises affixingleg 57 andnon-affixing leg 58, which have uneven lengths, as best shown inFIG. 12B.Hosel 55 has receivingarea 59 adapted to receiveshaft insert 54.
To assemble the club,shaft tip 60 is maintained belowdecorative ferrule 61 disposed onshaft 14, as shown inFIG. 12D.Upper end 62 ofshaft insert 54 is inserted intoshaft tip 60, andshaft insert 54 is fixedly attached toshaft 14.
Afterward, as shown inFIG. 12E,shaft 14, withdecorative ferrule 61 andshaft insert 54 is assembled withclub head 56. Specifically,lower end 63 ofshaft insert 54 is inserted into receivingarea 59 to connectshaft 14 toclub head 56. More specifically, affixingleg 57 is inserted intoaperture 64 and threadably attached tosole nut 65 inbore 66 ofclub head 56, whilenon-affixing leg 58 is mated to receivingarea 59 to minimize relative rotation between the shaft and the club head. Preferably,non-affixing leg 58 is conical, wedge, or other key shape.
Referring toFIGS. 1 to 12E and14A to 15G, the embodiments of the present invention are illustrated with various single thread fasteners. These fasteners can be right-handed or left-handed and can have single thread or multiple threads. These fasteners need to be sufficiently strong to withstand repeated impacts between the golf club and the balls. An impact can create a force of up to 2,000 lbs. and depending on the location of the impact on the hitting face,connection system 10 may experience a torque load of 2,000 · x, where x is a distance between the impact location and the neutral axis of the club. For example, a toe impact would produce more torque than a center impact. A heel impact would produce more torque (reverse direction) than a center impact. The density of threads and the dimensions of the threads should be designed to withstand the torque produced by toe and heel impacts.
FIG. 13A illustrates the force-flow lines 120 through a set of threaded fasteners used to clamp two members together. (Further detail can be found inFundamentals of Machine Component Design by Robert C. Juvinall, copyright 1983, by John Wiley & Sons, Inc.) Direct compressive stress, often called bearing, exists between threadedfastener 122 andcorresponding fastener 124. Stress (σ) is defined as load (P) 128 divided by the cross sectional area (A) 130 that exists when the load is acting: σ = P/A. In this particular situation, the area used for the P/A stress calculation is projected area 132 that, for each thread, is π(d²-d_i²)/4, where d 134 is outer diameter of fastener cylinder andd_i 136 is inner diameter offastener 122 contact withnut 124. The number of threads in contact ist/p, wheret is fastener length ofengagement 138 andp is fastener thread pitch, typically reported as inches per thread turn. (In practice, thread pitch is known by its reciprocal of threads per inch.) By substitution, σ = (4P/ π(d²-d_i²)) ·p/t. This equation demonstrates the advantage of more threaded contacts in the present invention, which is the strength of a set of threaded fasteners is proportionately increased by increasing the threaded fastener contacts. Preferably, fastener threads per inch is 12 to 36 threads/inch. More preferably, fastener threads per inch is 18 to 30 threads/inch and most preferably 24 threads/inch.
Increasing fastener contacts could increase the golfer's fastener tightening and untightening time, which is undesirable to a method for quickly and easily interchanging the shaft, removable weights and other attachments with the club head. Typically, threaded fasteners comprise a singlehelical groove 140 disposed on a cylindrical rod fromend thread 142, however if thehelix angle 144 is increased other threads may be cut between the grooves of the first thread, so fasteners can have two 146 or more parallel threads, as shown inFIG. 13B. (Further detail can be found inFundamentals of Machine Component Design by Robert C. Juvinall, copyright 1983, by John Wiley & Sons, Inc.) A fastener thread is assumed to be single thread, unless otherwise stated. Lead is the distance a threaded fastener advances axially in one turn. On a single threadedfastener 140, thelead 148 and pitch 150 are identical; on adouble thread fastener 146, thelead 152 is twice thepitch 154, etc. The end result is that the threaded fastener will advance twice as far in a single turn on a double thread fastener than it would on a single thread fastener, etc., so double, triple, or more threads are used whenever rapid advance is desired. The advantage of multiple parallel threads is that the thread count of the fastener connection can be increased to strengthen the fastener connection while minimizing the golfer's time to connect the threaded connectors together. Preferably, fasteners will be multiple thread and have the same direction. More preferably, fasteners will be double thread and have the same direction.
Referring toFIG. 13B, a thread may be either right-hand 140 or left-hand 146. Almost all threaded fasteners tighten, or move away from the viewer, when rotated clockwise; a left-hand thread advances when turned counterclockwise. A fastener thread is assumed to be right-hand unless otherwise stated. During use of an assembled golf club, swinging the golf club and hitting the ball tends to tighten or loosen threaded connections, depending on whether the club is right- or left-handed and whether the thread is right- or left-hand. For right-handed golf clubs, left-hand threading would tighten during ball striking; for left-landed golf clubs, right-hand threading would tighten during ball striking. Preferably, fastener threading would be matched to loosening and tightening needs, so that the club can be readily assembled and disassembled before and after use.
Referring toFIGS. 14A to 14E, another embodiment ofconnection system 10 comprises awedge hosel 160 with tapered receivingarea 162, a hollowclub head insert 164 that is fixedly attached toclub head 166, and awedge screw 168 with a first smoothtapered end 170 and a second threadedcylindrical end 172. Tapered receivingarea 162 ofwedge hosel 160 is adapted to receive taperedhead 170 ofwedge screw 168.Connection system 10 further comprises an anti-rotation device, made up of first serrated surface 174 disposed onwedge hosel 160 and corresponding secondserrated surface 176 disposed onclub head insert 164. Additionally, when taperedhead 170 is inserted into receivingarea 162, taperedhead 170 also minimizes relative rotation betweenclub head 166 andshaft 14.Wedge screw 168 is preferably aligned substantially perpendicular or orthogonal to the shaft.
To assemble the club,shaft tip 178 is maintained belowdecorative ferrule 180 disposed onshaft 14, as shown inFIG.14C.Upper end 182 ofwedge hosel 160 is sized and dimensioned to fit on the outside ofshaft 14, andwedge hosel 160 is fixedly attached toshaft 14 by means of adhesives, epoxies or similar materials.Shaft tip 178 is retained withinwedge hosel 160, as shown inFIG. 14D. Preferably,upper end 182 ofwedge hosel 160 is flush withdecorative ferrule 180.
Club head insert 164 is inserted the top ofbore 184 ofclub head 166 and affixed therein withdiametric aperture 186 ofclub head insert 164 aligned with threadedside aperture 188 ofclub head 166. Preferably,club head insert 164 is serrated or threaded on its outside surface to increase the surface area to adhesives or epoxies. Alternatively,club head insert 164 is made integral toclub head 166.
Thereafter,shaft 14 andwedge hosel 160 assembly, as shown inFIG. 14F, is inserted the top ofbore 184 ofclub head 166. The interaction ofserrated surfaces 174 and 176 ofwedge hosel 160 andclub head insert 164 directsshaft 14 withinbore 184 so that tapered receivingarea 162 ofwedge hosel 160 aligns withside aperture 188 ofclub head 166.Tapered end 170 ofwedge screw 168 is inserted throughside aperture 188 ofclub head 166 into receivingarea 162 ofwedge hosel 160 and threadedend 172 ofwedge screw 168 is releasably fastened into threadedside aperture 188 ofclub head 166.
Wedge 168 may comprise two components:wedge shell 169 and threadedfastener 171, as shown inFIGS. 14G-J.Fastener 171 fits withinwedge shell 169 and is rotatably connectinghosel 160 toclub head 12. The two-component wedge is similar to the one-component wedge, except that the threads are located on the inner threadedfastener 171 andwedge shell 169 has substantially smooth outer surface to fit snugly to receivingarea 162. The end ofwedge shell 169 can be conical, as shown inFIG. 14H or tapered, as shown inFIG. 14I. The conical end has an advantage of self-centering as twocomponent wedge 168 is being inserted intohosel 160. The tapered end has an advantage of providing an anti-rotation tendency betweenwedge 168 andhosel 160. Alternatively,wedge housing 169 can have a cylindrical outer shape as shown inFIG. 14J. In the cylindrical embodiment, all ofouter surface 173 is in contact withhosel 160 to provide enhanced contact between these two parts. Acover 175 is optionally provided to keepwedge 168 free of debris.
FIGS. 15A to 15D illustrate another embodiment ofconnection system 10 with abendable hosel 190.Hosel 190 is designed to bend preferable atsection 192, where the outer diameter ofhosel 190 has a substantial change.Hosel 190 can be bent aboutsection 192 to change the loft and/or lie angle of the golf club. Any bendable hosel with predetermined bends or any hosel with a weakened section can be used.Hosel 190 can be bent by automatic/motored or hydraulic bending tools, commonly used in golf pro shops, e.g., Steelclub Angle Machine sold by Mitchell Golf Equipment Co., and those used to bend pipes in the plumbing art. Suitable bendable hosels are disclosed in commonly owned, co-pendingU.S. patent application serial no. 11/621,754, filed on January 10, 2007, which is incorporated herein by reference in its entirety.Hosel 190 should be bendable only by equipment made for bending hosels, and not by impact with golf balls.
Similar to the embodiment inFIGS.14A-14F, this connection system also has an anti-rotation device comprising a firstserrated surface 194 on the hosel and a corresponding secondserrated surface 196 on hollowclub head insert 198. To assemble the golf club,shaft insert 200 with internal threads in first inserted intoshaft 14, and thenbendable hosel 190 is attached to the outside ofshaft 14, as shown inFIGS.15C-15D. The shaft and hosel assembly is then inserted intoclub head 202. Ascrew 204 is inserted intoheel opening 206 ofclub head 202 and is threaded intoshaft insert 200 to retainshaft 14 toclub head 202, similar to the retaining mechanism shown inFIGS. 1-4 and described above.
FIGS.16A-16E illustrate a system for retainingscrew 204 withinclub head 202 during the changing of hosel or club head. The connection system shown inFIG. 16A is similar to that shown inFIG. 15D, except forhollow screw cap 208. Afterscrew 204 is inserted intoheel opening 206, as discussed in the preceding paragraph, screw cap is inserted intoheel opening 206 and is sized and dimensioned to be positioned at a predetermined distance,1, below the top ofscrew 204, as best shown inFIG. 16B. Distance1 is preferably greater than the depth of the teeth ofserrated surfaces 194 and 196. When a user wishes to change the hosel or club head, the user would insert a screwdriver to similar tool intoheel opening 206, throughhollow screw cap 208 to the top ofscrew 204. The user would then unscrewscrew 204 to move screw 204 a distance1, or until the top ofscrew 204 comes into contact withscrew cap 208. At this point, the user can pullshaft 14 upward to disengage firstserrated surface 194 ofhosel 190 from the corresponding secondserrated surface 196 ofclub head insert 198. The user then can freely rotateshaft 14 relative toclub head 202 toseparate shaft 14 fromclub head 202. The advantage of usingscrew cap 208 is thatscrew 204 is kept within the club head and the chance of misplacingscrew 204 is minimized.
Screw cap 208, as shown inFIG. 16C, may havewaist 210, and heel opening 206 may have at least oneledge 212, as shown inFIG. 16D, adapted to be received withinwaist 210 to keepscrew cap 208 securely within the club head. Alternatively, as shown inFIG. 16E may have one ormore protrusions 214, as shown inFIG. 16E, to provide an interference fit betweenscrew cap 208 and the walls ofheel opening 206.
In another embodiment, the club head may have anopening 216 formed on its heel as shown inFIG. 17A.Opening 216 is adapted to receive a high impact transparent or translucent cap 218, which allows the user to view the mechanisms ofconnection system 10, as best shown inFIG. 17B. Suitable materials include, but are not limited to, polymethacrylate, cellulose acetate butyrate, polycarbonate (Lexan®), and glycol modified polyethylene teraphthalate, discussed above.
Another way to change the lie and/or loft angle of the golf club is illustrated inFIGS. 18A and 18B. Here,golf club 10 which includesclub head 12,shaft 14 andhosel parts 16 and 17, shown above inFIG. 5, hashosel insert 220 disposed betweenhosel parts 16 and 17.Hosel insert 220 have serrated surfaces on its top and bottom to match the serrated surfaces ofhosel parts 16 and 17, so thathosel insert 220 would fit flush in between. To change the loft/lie angle ofclub 10,first side 222 andsecond side 224 ofhosel insert 220 are different from each other, ortop line 226 is not parallel tobottom line 228, as illustrated by lines 226' and 228'. In other words,hosel insert 220 is askew. In one example, iffirst side 222 is shorter thansecond side 224, then $angle α > angle β$
and α = 91° and β= 90°, then the shaft angle has been shifted by 1°. If the shaft coincides with the vertical axis then the shaft would have been shifted towardfirst side 222 by an amount equal to $|90 ° - β| + |90 ° - α|$
In this example, iffirst side 222 andsecond side 224 are oriented in the toe-heel direction, thenhosel insert 220 can change the lie angle. Iffirst side 222 andsecond side 224 are oriented in the front-rear direction, thenhosel insert 220 can change the loft angle.
It is noted thathosel insert 220 does not need to have the serrated top and bottom surfaces as shown, so long as these surfaces match the corresponding surfaces onhosel parts 16 and 17. For example, if the corresponding surfaces ofhosel parts 16 and 17 are linear or curvilinear, then the top and bottom surfaces ofhosel insert 220 can assume the same shape. Furthermore,hosel insert 220 can be positioned aboveclub head 12, as shown; however, it can also be located inside the club head.
Furthermore, one of the hosel parts, can be made integral withclub head 12, as illustrated inFIG. 20A. The hosel parts are preferably made from low density aluminum so that more mass can be distributed elsewhere to improve inertia and center of gravity properties.FIG. 20A is similar toFIGS. 1-5 and is illustrated with similar reference numbers. As shown,hosel part 18 is made integral toclub head 12 and matchingserrated surfaces 17 and 19 are positioned aboveclub head 12, similar to the view shown inFIG. 5. Furthermore,hosel insert 220, shown inFIGS. 18A-B, can be used with this embodiment to change the lie and loft angle without bending the hosel. Alternatively, as shown inFIG. 20B, matchingserrated surface 17 and 19 are positioned internal toclub head 12. In this embodiment,serrated surface 19 may be formed directed onclub head 12 during the casting process, andhosel part 18 can be omitted. Also, threadedshaft insert 20 can be omitted, whenhosel insert 16 has threadedinternal surface 238, sized and dimensioned to receivescrew 24 to attachhosel 14 toclub head 12, as shown inFIG. 20C. An advantage of this embodiment, is that it has fewer parts than the embodiments shown inFIGS. 20A and20B and that instead of the smaller contact surface betweenshaft insert 20 andhosel 14, a larger contact surface betweenhosel 14 andhosel 16 is available to be epoxied together to withstand the impact force between club and golf balls.
To minimize the possibility of vibration caused by ball-club impacts, a damper or a preload spring can be added, for example between the shaft and the club head or portion thereof as shown inFIG. 20D. FIG. 20D is an enlarged portionFIG. 20C, showing damper/spring 240. It is noted that damper/spring 240 can be used with any of the embodiments discussed and claimed herein.Part 240 can be an elastomeric or viscoelastic member designed to absorb vibration caused by impacts, and can be compressed between the hosel and the club head, as shown. Alternatively,part 240 can be one or more spring washers being compressed between the hosel and the club head to absorb the vibration. Suitable spring washers include, but are not limited to, Belleville or cupped spring washers, star spring washers, wave spring washers, curve spring washers, and locking washers.
Also, any of the threaded connections described herein, can be reinforced by a threaded helical coil, commercially available as Helicoil™ from many sources, including Emhart Teknologies. These coils are precision formed screw thread coils made from stainless steel, titanium or other durable metals, that have a diamond shaped cross-section. These coils are inserted into threaded holes, and are adapted to receive threaded fasteners. These coils are designed to be placed snugly between the threaded fasteners and threaded holes, and are designed to spread the load evenly among the threads. Typically, these coils are harder than the holes and the fasteners to minimize the possibility of thread tripping.
Typically,shafts 14 are long and slender and their geometry affects the number of teeth that can be present onserrated surfaces 17 and 19, as shown generally inFIGS. 1-2, as well as the geometry of these teeth. The size of the teeth also needs to be sufficiently robust to withstand the stresses and torque applied to the shaft. The cutting tools have their own limitation as to how small they can cut the serrated teeth. The inventors of the present invention have discovered that in one preferred embodiment three teeth on eachhosel insert 16, 18 can sufficiently perform the anti-rotation function, as shown inFIGS. 19A-C. As shown,hosel part 16 has three thicktapered teeth 230 andhosel part 18 has three corresponding thintapered teeth 232. Alternatively, thicktapered teeth 230 can be associated withhosel part 18 andvice versa. The slopes of taperedteeth 230 and taperedteeth 232 are substantially the same and are from about 20° to about 40°, preferably from about 25° to about 35°, and more preferably about 30°. Such angle extends the wear of the teeth and allows debris and dirt to escape.Teeth 232 can be from about 0.07 inch to 0.25 inch in height, preferably between about 0.09 inch to about 0.20 inch in height, and more preferably between about 0.10 inch to about 0.15 inch in height.
In accordance with another aspect of the present invention, the tapered teeth (or prongs) onserrated surfaces 17 and 19, such asteeth 230 and 232, do not come into contact with the opposing hosel part, so that the tapered teeth or prongs don't bottom out or come into contact with the opposing hosel part. In other words, agap 236 shown inFIG. 19A is present whenhosel parts 16 and 18 are assembled. This provides a manufacturing tolerance so thathosel parts 16 and 18 can fit flush together. For example, if nogap 236 is allowed and one of the teeth is slightly longer than the rest, then when assembled this longer tooth prevents the two hosel parts from coming flush together.FIG. 19D illustrates another example ofgap 236 with taperedteeth 230 and 232 having substantially the same size.
The embodiments of the present invention are illustrated with driver-type or iron-type clubs. However, it is understood that any type of golf club can utilizeinventive connection system 10. Additionally,connection system 10 can be used with non-golf equipment, such as fishing poles, aiming sights for firearms, plumbing,etc.
While it is apparent that the illustrative embodiments of the invention disclosed herein fulfill the objectives stated above, it is appreciated that numerous modifications and other embodiments may be devised by those skilled in the art. Elements from one embodiment can be incorporated into other embodiments. Therefore, it will be understood that the appended claims are intended to cover all such modifications and embodiments, which would come within the spirit and scope of the present invention.

Claims

A golf club comprising a shaft, a club head and a connection system, said connection system comprising a spring loaded bayonet mount, wherein the spring has a spring constant, k, from about 5 pounds-force/inch to about 100 pounds-force/inch and wherein the spring loaded bayonet mount is located above the club head.
The golf club of claim 1, wherein the spring constant is from about 20 pounds-force/inch to about 75 pounds-force/inch.
The golf club of claim 2, wherein the spring constant is about 33 pounds-force/inch.
The golf club of claim 1, wherein the bayonet mount comprises at least one post disposed on the shaft and at least one corresponding channel disposed on a hosel of the club head and the bayonet mount further comprises a spring disposed within the hosel.
The golf club of claim 4, wherein said channel comprises a reduced diameter section sized and dimensioned to releasably retain said post.
The golf club of claim 5, wherein
said reduced diameter section comprises a triangular section; or
said reduced diameter section comprises a waist section.
The golf club of claim 1, wherein the shaft includes a distal engagement portion and a proximal portion, wherein the distal engagement portion engages the club head and the proximal portion extends from the distal engagement portion to a grip end of the shaft, and wherein the distal engagement portion defines a longitudinal axis that is angled relative to a longitudinal axis of the proximal portion.
A golf club comprising,
a shaft including an engagement portion;
a club head including a crown and a hosel extending away from the crown; and
a spring disposed in the hosel,
wherein the engagement portion is at least partially received in the hosel and releasably coupled thereto, wherein the spring is at least partially compressed when the engagement portion is coupled to the hosel, and wherein the engagement portion includes at least one post extending outward from an outer surface of the engagement portion and the hosel includes a plurality of channels configured to slid ably receive the at least one post.
The golf club of claim 8, wherein
each of the plurality of channels is J-shaped; or
the engagement portion is a sleeve member that is attached to a proximal portion of the shaft; or
the shaft includes a proximal portion that extends from the engagement portion to a grip end of the shaft, and wherein the engagement portion defines a longitudinal axis that is angled relative to a longitudinal axis of the proximal portion.
The golf club of claim 8, wherein the post is movably coupled to the engagement portion.
The golf club of claim 10, wherein
at least one of the plurality of channels includes a receptacle that receives at least a portion of the screw, wherein the engagement of the receptacle and the screw prevents relative motion between the shaft and the club head; or
the post is a screw including a countersunk head, and at least one of the plurality of channels includes a countersink that receives the countersunk head.
The golf club of claim 8, wherein the spring has a spring constant having a value from about 5 pounds-force/inch to about 100 pounds-force/inch.
The golf club of claim 12, wherein the spring constant is from about 20 pounds force/inch to about 75 pounds-force/inch.
The golf club of claim 13, wherein the spring constant is about 33 pounds-force/inch.
The golf club of claim 8, wherein the plurality of channels are equally spaced circumferentially about the hosel, preferably wherein the number of posts equals the number of channels.