CA2131331A1 - Hollow, large, metallic, golf club head - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A golf club head comprising a shell having toe and heel portions, a rear wall, a front wall defining a ball-striking face, and top and bottom walls, the bottom wall characterized as having a medial ridge, and as forming two dished shallow recesses, one recess between the ridge and the heel portion, and the other recess between the ridge and the toe portion, the recesses spaced rearwardly from the front wall, the one recess having an arcuate peripheral edge generally convex toward the heel portion, and the other recess having an arcuate peripheral edge generally convex toward the toe portion, the recesses being located in substantially mirror imaged positions with respect to a forwardly extending vertical plane bisecting the ridge, the head, when viewed toward the bottom wall, presents a peripheral outline which, at the toe and rear of the head, has substantial spacing from the other dished shallow recess.

Description

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- 2~1331 ` -~AC~ROUND OF TH~ INVEN~ION

Thi~ applicatlon i~ a continuation-in-par~ of Ser~al No. 0~173,389, filed January 6, 1994, which is a ;
continuation-in-par~ of Serial No. 08/029,553, filed March 11, 1993, which i~ a continuation of Serial No 07~819,379~ ~iled January 15, 1992, now U.S. Patent 5,240,252 ~issued ~August 31, 1993, which is a continuation-in-part of Serial No. 07/791,322, filed November 14, 1991, now U.S. Patent 5,180,166 issued January 19, 1993, which is a continuatlon of Serial No.
07/595,963, ~iled October 16, 1990, now U.S. Patent ~,067,715 issued November 26, 1991. ``
This invention relates generally to increa~ing the siza o~ metallic, hollow, golf club heads (woods) `
wlthout increasing head weight to facilitate ball stroking acauracy. Also, it concerns configuring an enlarged head in such mannsr as to resi~ de~lection of the ~ront wall and to absorb shoak waves at top, bottom, and rear wall~
Vary large, vary thin-walled, ~etal, golf club ,~ i `'heads present~problem~ o~ cracking and buckling o~ metall ;
walls, and exce~sive front wall deflection, during ball impact. There i8 need to provide an improved metal head con3truction and/or con~iguration which guides, interrupt~, sprea~s~ or otherwi~e altera the sho~X wave3 which emanat~ ~rom th~ ~ace at impact, but whilQ ~ ;
maintaining r~duc~ wall thic3une~e~
~hQre i8 al~o need to strengthen th~ thinned w~ and/or ~ole plate~, of suah gol~ club head~, as ;~ -; ` ; 21~13~ ~ :

well as to reduce drag forces at ~uch bottom walls during stroklng.

: SUMMARY OF TH~ INVENTION
~ ' It 1s a ma~or ob~ect o~ the invention to provide ~truc~ur2 overcoming the above problems and d1sadvantages. Basically, the improved head o~ the lnvent1on~1s eharacterized by a ball striking front wall, a bottom wall, and spaced to~ and heel walls, the ~ottom ~;
wall character$zed as having two shallow recesses~ one recess aloser to the heel portion, and th~ other recess ~:
closer to the toe portion, the recesses being ~paced ~::
rearwardly ~rom the ~ront wall, one recess havlng an arcuate peripheral edge generally convex toward the heel portion, and the other recess having an arcuate peripheral edge convex toward the toe portion.
Such reces~es typically have down~ardly ~acing .. `
~surf2ce~ w1th ~hallow, upwardly d~shed con~iguration. ~ :
he:downward ~aaing surfaces are concave in ~ront-to-rear direction~ and ths downward ~aolng ~urfaces are al80 `.`. :,:``
.~lc~ncav~ 1~ direction~:between ~h~h~el.and toe~c Anoth~r obJect is to provids a head which, when . viewed toward t~e:bottom wall, presents a pQrlpheral :
~ outlino which, at the toe and rear o~ ~h~ head, ha~
: substantial ~pacing rro~ the other dlshed ~hallow rece~
A~ will b~ ~een, thQ ~paaing betw~en th~ paripher~
outlino at th~ toe and the other d1shed r~ce88 i3 i,~''`' typlcally at least 5/8 inchs andithe ~paclng between that ~;.. `
outline at the head xear and othQr di~hed reoes~ i~ at ~`~

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~` ~ 2 1 3 ~. ~ 3 1 least about 1 inch. The~s large spacing~, da~ined by arcuate 810p~8 0~ head wall portions, contrlbute to head wall ~trengthening, to enable head enlarg~ment.
A further ob~ect i8 to provlde a head with a peripheral outline, as referred to, and which encompasses an area A, and the dished rece~se~, ridge and bevel define an area B, when viewed toward the bottom wall o~
the head~, and where ~ > 1.6 B. Typically, A is related to B by th~ expression 1.7 < A/B < 2Ø
Another ob~ect i8 to provide botto~ wall localized struc~ure tha~ will aid in "digging out" a golf ball having a ~ad lie from the turf.
Another ob~ect i8 to provide such a head wherein the bottom wall has a bevel that extends at a rearwardly and upwardly extending angle, beyond rearward oxtent of a medial ridge, and batween rearward extents of th~ localized rece~ses. That b~vel may merge with pQripherles o~ th~ dishad reoesses, as wlll appear. The bevel i~ spaced at least 3/4 inch ~rom the rear periphery o~ the head, a~ viewed toward thQ bottom wall of the : ~
head.
A ~urther ob~ect is to provide the bottom wall to be ln part de~ined by a ~ole plate having a peripheral edge rigidly connectsd to the bounding edge o~ an opaning de~ined by the bottom wall, rearwardly o~ th~ ~ront wall, ~; whereby the sole plate clo~e~ the opening, tha ~edial rid~e and reces~e~ al~o baing in part de~lned by the ~ole plat~. In this regard, the 8018 plate typically de~ine~
ma~or ~xtent~ o~ the shallow reces~. A head body ~h~ll may al~o degine a rigidizing bot~o~ wall corner plate ~ ' ' '' ~ection integral wi~h shaft supporting tube ~tructure, tha sole plate al~o connected to that corner plate ~:
~ection, the corner plate ~ection al60 forming a portion of tha on~ shallow reces~ closest to the head heel portion. -Yet another object i8 to provide a first group ~
of narrow, metallic, shock wave distributing dendrites ~ :
extendlng from the ~ront wall generally rearwardly adjacent the under~ide of the shall top wall and integral -.
therewith, the dendrites pro~ecting to~ard the two shallow recesse~, the bottom wall defining those recèsses `. -.
being upwardly concave toward the dendrites~
A second group of dendrite~ may also be , ;, provided to ba integral with the top wall and spaced ~.
apart to extend generally rearwar~ly to merge rearwardly .
:: .
and downwardly with a rear wall definQd by the shell to transfer rearward loadlng to that wall as the dendrites pi¢k up rearward loadlng from the top wall in re6pons~ to ;`.;;`;I.
~ront wall impact with a golf ball, the ~econd group o~
-.-~ ~ 20 dend~ltes al80 pro~acting toward the two shallow ~`~
~ :.. -,. ;.
~ recesses.
.~ ,; .. ~ .
h~ dendrites are such as to transfer, spread,~
dampen, and:dl~tribute ~mpact-produced ~hock 80 a~ to : reducQ shoak wave concentration otherwise imposed on the i .~`
~unction between th~ ~ront wall and top wall. Shock ;.. ~
;~ ~ waves are produced by high ~peed impact of the club head .;
with the golf ball, whlc:h laave~ the head ~bout 1/2 : millisecond a~ter impact, ~or a driver with head .` ;
traveling at 100 miles per hour. The di~hed wall~ of th~
plate also ~tren~then tha structure ~or ~hock load ` ~`~

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transmlssion.
It i~ another ob~ect to provide hosel ~tructure that extends downwardly into the head interior and ~orm8 a ~haft-receiving opening. Thi~ strengthen~ the ~ ;
connection of the ~ro~t wall to the dished ~ole plate and heel, and reduces hosel weight, ~o that such weight can be utilized to form the dendrites, as referred to. In thi regard, the inventlon enable~ the provision of a larger overall volume head, as compared with the head o~ ;
the same weight, but lacking the dendritic ~tructure, as referred to. As will be seen, the use of such strUctur Pnables thinning o~ the hollow head top, toe, bacX, and ~
heel wall~. -Anoth~r object iB to provide a head bottom wall which controls engaged turf relative movement (during a gol~ swing) 80 as to create upward force or force acting on the head in a manner resulting in reduced drag a~ the head is swung.
Another ob~ect is to provide a set o~ golf club head~, ~ach head comprising a shell having toa and heel ~ ~;
portlon~, and a ~ront wall de~ining a ball striking fac~, and top or bottom walls, the ball ~triklng ~ace~ of ~hQ~
heads having varying angularities with re~pect to vertical~ the bottom wall o~ each head ha~ing a medial ridge, and forming ~wo ~lshQd, 3imilar ~hallow r~ces~es, one racess between the ridge and heel portion and ~h~
other racess between the ridg~ and toa portion, euch rece~ses located rearwardly o~ the ~ront wall, one reces~
having an arcuate p2rlpharal edyo portion generally convex toward the heel portion and th~ other recess : "'', , ~.

2 ~ ~ ~ 3 ~

having an arcuate peripheral edg~ portion gener~lly -convex toward tha toe portion. Each rece~s o~ each head ;~
may have a downward}y facing surface further characterized in that~ for each head, ~;
::, ..
i) a vertical plane bisecting thQ :,, .
recess ~n a toe-to-heel direction intersects the rece6~ ~urface along .
a downwardly concave line, and ii) a vertical plane bisecting the recess in a ~ront-to-rear direotion `~
relative to the head interseats the recsss surface along a downwardly concave line. ~;;
Also, the two concave recess2s of each head -typically hav~ similar conflguration with re~pect to a ~
vartical plane that b~sects the ridge in a front-~o-raar`~```
direction relative to the head. Further, each recess o~ --: ;,.,.. :
each ~uah head may have a downwardly ~acing ~urface further characterized in that, ~or each head, ;
~ 20 i) the rearwardmost extent o~ th~ ~i -~ downwardly ~acing sur~aca i~
, ; inclined ~orwardly~ and upwardly` -relative to the haad forward swing path as the head bottom wall engage~
the tur~
ii) whe~eby li~t ~orce i8 created in -~
respon~a to engagaDent ~ the rearwardmo~t extent oP the sur~ace with the tur~, ac thQ haad t~ ~wung - `
~orwardly along th~ path, ~uch lift , ~
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force acting to urgs the head botto~
wall and the head in an upward .-direction. ~:.
Yet another ob~ect i8 to provide ~or each head a bottom wall having a rearwardly divergent ~ur~ace :~ (which may be locally flattened) ~hat extends at a rearwardly and upwardly extending angle, beyond rearward :~ extent o~ the ridge, and betwPen rearward extents~of the ;~
recesse~, ~or reducing drag as th2 head i~ ~wung ..
~orwardly in an arc, ad~acent the turf. In this regard, ~ ;
guided engagement with the turf and upward force exertion : ~`
ar~ enhanced by a configuration wherein th~ rearwardly divergent sur~ace and th~ two recesses have edge~ which, when viewad from the rear of the head~ are upwardly convex. ~l~o, ~or each head, there may ~e provided a ~ubstantially continuou~, hollow, metallic tube extending wlthin tha ~hell o~ the heel portion and from proximate .~
; the ~hell top wall to proximate the ~hell bottom wall, ` ~:
that tube having a borQ to rQceivQ a club ~ha~t, th~ ~ors aligne* with the one shallow rec~ss. -.
further ob~a¢t i~ to provid~ a set o~ head~, as referred to, which include~ at least two or more o~
t~ ~ollowlng~
. a) a metal wocd havlng a ~xont ~ace inclined ~:
at approximately 9 Pro~ v~rtical, ~`
b) a metal wood having a ~ront ~ace incllned ~t approximately 11- ~rom vertical, c) a metal 2 wood, d) a metal 4 wood, e) a metal 5 wo~d~ ~ `

= 8 ~-~

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Yet another O~ QCt 0~ tha inventlon ~ 8 to ~: .
provide a e~ 0~ heads characterized by ons o~ the ~ ~
following: - .
a) at least one head has a center o~ gravity ~ :`
located at approximately 42~ to 50~ of the head height, .::i-.
a~ measured upwardly ~rom the lowermost head surface to .~
the uppermost head sur~ace, viewed fron the front o~ the -.
head, ;``
b~ each of at lea~t two o~ the heads has a :.
center of gravity located at approximately 42% to 50% of tha head helght as measured upwardly rrom the lowermost ~.
.... . ~
head ~urfac~ to the uppermost head surface, viewed from the front o~ the head.
A still furth~r ob~ect is to providQ an .`~
: 15 improved gol~ alub head, and method of ~orming i~ame, to .
incorporate component~ ln construction, mode of operation .``".
and re~ult~, whan used, a~ referred to. ` -`
These and other ob~ects and advantageis of th~
inventlon, a~ well as the details of an illui~tratiVQ .
embodiment, will: b~ more ~ully undQrstood fro~ tha ~ollowing speci~1cation an~ drawings, in which:

DRAWING D~SCRIP~ION

~lg. 1 ie a ~ront elsvational view of a gol~
alub head incorporating the inventiont ?'~
Flg. 2 i~ a plan view o~ tha botto~ o~ ~h~ Fig. ~``
1 head; .~::
F~g. 3 i~ ~n elevat:Lonal view o~ the toe end o~
: tho Fiq. 1 heads , ", ;,:
_ g _ , ~
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Fig. ~ is an alevational view o~ the h~el end of the Flg. 1 head: ~ .
Fig. 5 is a rear elevation view o~ the Fig. 1 head, Fig. 6 i~ an elevation taken in section on ~: lines 6-6 o~ Fig. 2; .
:~ Fig. 7 is an elevation taken in section on lines 7-7 of Fi~. 2;
Fig. 8 i~ an elevation taken in section on lines 8-8 of Fig. 6;
Fig. 9 is an elevation taken in section on lines 9-9 o~ Fig. 6;
Fig. 10 is a plan view showing ths bottom o~
the Flg. 1 head, but prior to attachment o~ a 801~ plate;
Fig. 11 i3 a plan ~iew of the sole plate that :
fits into ths bottom opening shown in Fig. 10; : :
Fig. 12 i3 a fragmentary ~ection showing dendrite structure;
Fig. 13 iB a fragmentary section ~howlng dendriteis extending rearwardly from the head ~ront wall;
Fig. 14 i~i a fragmentary section ~howing :~
~ dendritesi ~xtending rearwardly downwardly ad~acent thQ ~.
: top and rear walls of the head;
Fig. 15 is a perspe~tive view o~ the Fig. 1 head; and ~.
Fig. 16 is a top plan view og the Fig. 1 head.
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DETAIL~D D~SCRIP~ION

Rsferring now to ~he drawing~, a gol~ club 10, ~: in accordance with a preferred embodiment o~ the present ; invention, is shown. The club 10 include~ a sha~t 12 .
(only ;the lower portion o~ which ls shown), which i8 ' attached ~to ~a :head 1~. Tha head 14 is in th~ .
configuratlon o~a~"wood'5 club, althou~h it i8 made o~
: metal.~ A~s~shown in Figs. 6-9, tha head compr~ses a ~
hollow, meta1 ~hell 16, which i8 filled with a plastic ,~.
~oam fllllng 18, preferably polyurethane.
he shell 16 i8 preferably made of titanium or -tltanlum alloy; and~it may be fabrica~ed by the "lost ~;~ wax" casting method~that ls well known in the art. Th~
,,, ~ ., ~: ~hell 16 is ~ormed in two piaces: a main portion 20 and .
~; 15 a ~ole plate 22 that~is peripherally welded to the main ;~ portion 20, and a~ wlll be re~erred to. See weld : ~ location~ at 22~ and 22k in Flg. 6.
, . ;.~
`~ ~ The main shel} portion 20 has a top surface 24, .`~a rear sur~ace 26, and a ball-striking ~ur~ace or faca 28 .^~
oppo~ite the rear ~urface 26. Ths ~ac~ 28 18 angled with re~pect to the vertical with a ~peci~ied npi~ohn that i~
determinad by the type o~ club and t~e amount o~ loft desired. :~he ond portlon o~ the head 14, proximate th~
shaft 12, :i8 commonly termed the "heel~ 30; while th~ end portlon, oppo~ite the he~l 30, i~ termed the "to~" 32. `~
how~ in Fig. 2, thQ ~ao~ 28 i~ typically ,~ . ,~ . .
~urv~d ~rom the heel 30 ~o the toe 32. The main ehell por~lon 20 ha~ a bottom corner portion 34 tshown ln Flg. .:`
10) that i~ cast integrally wi~h the ~ront wall 28~ and .. `
. ~ ,. .
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"',,` ',,' ' ,', ".
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2131~3~

with thQ haal wall 30a, and ~lush with the 501a plate 22, that form~ a bo~tom sUr~aC~ or 801~ ~n combination with the sole plate 22 when the two ~hell portions are welded together.
~ 5 Referring now to Fig. 6, thQ heel wall 30a o~ :
: the shell 16 i~ provided with a substantially continuou~
: hollow tube 36 that extends ~rom an upper opening 38 in ths top sur~ace 24 to a lower elliptical opening 40 in tha bottom surface or sole through the bottom corner portion 34 o~ the main ~hell portion 20. The tu~e 36 i5 ~. `
o~ sub~tantially uniform internal diameter; and i~s side ~:
wall is interrupted by an internal orifice 42 that open~
lnto the interior o~ the shell. The orifice 42 provideR
an entranae for the introduction of tha foam material 18 into the hollow shell interior during ~he manufacturing . ``
proaess. -:
Tha tube 36 iR dimen~ioned to receive the lower ;`:
part of the shaft 12 with a snug fit. The upper opening ~"
38 is provid~d w1th a radiused lip 43, as ~hown ln Fig. `
:: 20 6, to minim~ze the possi~ility of strefis fractures in ~h~
. .~
shaft, due to impact against the edge o~ the opaning. A
portlon o~`the lnterior wall o~ the tube 36,~extending downwardly ~xom ~h~ upper opening 38, ~ay be provlded with atriation~, preferably in the form o~ internal threads, or a serie3 o~ concentrlc ~teps 44, to pr~vide a Nglue lock" ~or better bonding o~ the ~ha~t in thQ
tub~.
In the preferred embodiment o~ th~ invent~on, th~ llp 43 1~ at the end o~ a ~light riBe at tha heel end oP the hsad, tha height o~ the rl~e being ~llghtly les~

`. ' ' 2 ~ ~ 1 3 ~ ~L ! " ;~

than, or ~pproximately e~ual to, the height o~ a : .
horizontal plane 200 defined by ths hlghest point o~ the club head top ~ur~ace 24. -`~
The shaft 12 i8 a hollow tube made o~ any suitable material. Steel is ~he most common material, .
. . :~ . .
but tltanium and graphite-boron may also be used~ I~ the shaft 1~ o~ steel, th~ exterior o~ the shaf~ may be -- `
chrome-plated to minimize corro~ion. The lower part of tha sha~t may be fitted with a plug 46 to prevent the 10 entry of moisture ~nto the interior of th~ shaft. The ~ :
plug 46 may be of any suitable resilient mat~rial, such as Nylon, epoxy, polyurethane, or Delrin. The plug 46 may be retained in the shaft by an annular crimp in the ~:.
sha~t wall. The crimp also serves as a glue lock. A ~i.
locator ring 5Q, preferably o~ glass fiber-reinforced ~.
Nylon, is adhesively bonded to the shaft at a di~tance . `
above the bot~om en~ 52 o~ the sha~t, approximat21y equal .~
to the langth o~ th~ tube 36. ....
Th~ sha~t 12 may be attached to the head 14 by ~`
a ~uitable 8po~y adhesive, the ~tep~ or threads 44 in the . `
tube 36 and the arimp in the shaft provid~ng glue lock~, ; l a~ mentioned above, for better adhe~ive bonding. (Any~
plating on the lower part of the ~ha~t ia f~rst buffed n of~.) Durlng a~embly, ~ha lower part o~ ~ho ~haPt 18 .
inserted into tha tub~ 36 ~ntil tha locator ring 50 abut~
against th~ radiu~ed lip 43 at the upper tube opening 38. .
The bottom end 52 o~ the sha~t 12 ~hen extend~ sliqhtly beyond th~ lower tube open~ng 40. Thi~ bottom end 52 i~
then out and ground ~o as to b~ ~lu~h with the sole o~
the head, a~ shown in Fig. 6~

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The structure de~cribed above allows ths shaft to be at~ached to the head without a neck vr ho~el- ~B
a result, ~ub~tantially all of the mass of the head i~
"effective mass" that contributes to the transfar o~

5 energy ~rom ~he player ~o the ball, with little or no "deadweight~'to reduc~ the attainable club head velocity.
By inoreasing the effective mas~ of the club head wlthout reducing th~ attainable velocity, thera i8 a more effectlve trans~er of energy to the ball from the player, 10 yielding increa~ed shot distance wi~hout an increase in effort on the part of the player.
Moreover, without an external hosel, the lower part of the shaft may extend all tha way through the head, with the bottom end 52 of the shaft ~erminating 15 flush with the sole. ~hu~, by eliminating tha axternal hosQl, the shaft both enters, and may exit, the head, within the area defined between the top and bottom of tha ~aae o~ the club head, which area i8 sometime~ called the ~'ball control zon~". By bringing the lower end of th~
20 shaft wi~hin the control zone~ and ~x~ending the sha~t deeply into tho head ~hell, for axampla through to the ~ sole of ~h~ club head, the tactile sense o~the location : o~ th~ club faca, or "head ~eeln, i3 maxi~ized, yielding lncreased control o~ th~ 6hot, greatsr ability o~ ths 25 skllled player to ~wor~'l the ball, ànd a ~ore ~ol~d ~ael o~ impact with th~ ball regardless o~ whero on th~ ~aca th~ b~ll is struak. The increasQ ~n ~fective mass the club head, and th~ rigid support ~or the lower end of khe sha~t, providad by ~he in~ernal tuba 36 ln which the 30 lower end o~ the ~haft i~ received, ~urther contribute to .:

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213133~ ;
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this improvement in "head ~eeln.
Furthermore, a number of advantages in the ~-manufacturing process can be achieved by ~liminating the hosel. For example, the mas~ that would have been taken up by the hosel can be redlstributed to a part o~ the club head where it can contribute to the ef~ective mass ~ `
of the head without ~ncrea~ing the total head mass.
Optimally, this mass can be added by increasing the overall ~ize o~ the club head.
Still another advantage o eliminating the hosel is that there i8 a more even cooling of the club head ~n the mold. Where there ~ 8 an upward ho~el, by comparison, the hosel and the re~t of the club head ~h~ll may cool at unequal ra~e~, thereby resulting ~n a slight warping that can produce a lac~ of uniformity ln loft, "`~
lle, and ~ac~ angle from ~lub head to club head.
A gol~ club, in accordance with a preferred embodlment of the inventlon, includes the ~ol~ ;
aonfiguration shown in the drawings. A~ ~hown ln the drawlngs, the bottom wall i8 characterized a~ ~orming ~
medial ridge 60, and a3 forming two shallow recesse~, one recees between the ridge and the heel port;~on, andl th~
other recess betwoen the ridge and the toe portion, th~
reces~es everywhe~s spaced rearward~y ~ro~ th~ ~ront ~;~
wall, the one rec~ss h~vlng an arcuat~ periph~ral ~dgQ
` generally convex toward the heel portion, and ~ha other recess having an arcuate pQrlphQral edge generally convex toward tha toe portion. Examples o~ ~u~h ~hallow, upwardly dl~hed rece~ses are saen at 1~2 between the ridga 60 and the toe 32, and at 16~ between the ridge an~
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heel 30.
RQceB8 162 curved periphery extend~ in a looping edge path, indicated at 162a, 162b, 1~2c, and 162~. Recess 164 also extend~ ln a looping edge path : 5 indicated at 164a, 164~, 164c, and 164d, both paths ~: located on the bottom wall, as shown. The maximum depthof each recess below a plane containing its paripheral loopin~ edge path 1~ less than 1/4 inch, and prefsrably between 1/16 in¢h and 3/16 inch. See depths dl and d2 in Fig~. 8 and 9. These depths are sufficient normally to . ,:
avoid: direct frictional con~act of recess dished ~:~ innermost ~urfaces 162~ and 16~' with the ground during .~;
:~ a club ~troke, ground contact, if any, being confined to ~ th~ lowermost extQnt o~ the central ridge 60, and ~o ' ::
racess peripheral or rearward wall extents, a~ will appear.
Also, the upward bi-directional concavity o~
the bottom wall extents 162~ and 164' ~orming the ~ recesse~ adds to bottom wall ~trength, and ~tif~nas~, ~or :~ 20 transm1tting ~hock loading ~ran~mitted to and from tha ront wall 28 during ball strokin~. Tha bottom wall :.
thicknes~ " may then be ~inimized and ~etal rQd1stributed", to enab~ provi~lon of a larger ~lzed head.
Note also the provision o~ a botto~ wall .
; rearwardly divergent ~urface, or beYel, whlch ext~nd~ at a rearwardly and upwardly extend~ng angl~, b~yond rearward extent o~ the ri~g~, and ~etween rearward ~xtent~ of th~ race~ses.
Speai~ically, there i~ a trail~ng, bev~led ' ~ .
'~, - 16 - ~
, ' '.'~

` 2131~31 `: -surface 56, which i~ a rQlieved, upwardly angled, - ;~
~omewha~ ~lattened por~ion extending upwardly from a curved edge s6a, and between that edge and thc center o~
the sole, and a tralling edge 58 at the ~uncture between ~-~
the rear surface 26 of the club head and the sole plate 22. The lowermost curved part 56a of the sur~ace 56 i~ .
: .. .
con~iguou~ with tha rearward end of ridge 60 that extend ~orward toward and diverges at 60a and 60~ to merge . .
latorally with the bottom U-shaped lower edge 28a o~ the ~.
face 28 of the club head, edge 2~a being addre~sed toward .
the tur~, as the head i8 swung. .
Ths ~railing urface or bevel 56 pre~erably ;.
,:
extends at an anqle a of approximately 18~ to 25- with ~
respect to the horizontal. Sea Fig. 8. The angle ~ may ~.-be varied by plus or minus up to about 5-, depending on the ~ype o~ olub and the preference of the player. The ;~;
trailing surfaaa 56 minimlzs3 ~he alub head's closing, or "hooding'~, when the ball i8 hit ~'~at~, while redu~ing the ~.
: ~ overall aerodynamic draq o~ the alub head to maximi~e lts ~``
:20 atta~nable velocity during the swing.
Further, in regard to tha describ~d combination : of bottom wall contours, the ridge downwar~ curvature : :
~. .
~ rearwardly of the front faca, and between th~ dish6d .~`.
. .
recesse3 162 and 164 en~ble~ the 801e to penetrat~ the tur~, resi~ting and repelling the ~ur~ again~t the diehed~`~
out zonea 162 and 1~4 to lim~t pene~ration in proportion ~.
. . .
to or accordance with the uni~ue shape o~ the sole a~ a unit, in ~ unlyue way, the rront ~ace havlng a downward U-shapa ~orward o~ the rece~6e3 and ridqe, as $~ clear . .

~1~133~

~ro~ Fig~. 1 and 2. Note tha rldge diverg~ng ~orwardly toward the U-shaped ~ront face. ~ -.
Accordingly, a golf ball having a "bad lle" can . .
~ be approached in a confident way, to "dig" the ball out : 5 by means of a club stroke characteri~ed in that the club head 801e planes over the tur~, considering the tur~ a~
fluid. For a gol~ ball having a more conventional lie, no "digging out" i8 required, and an improved downward sole shape "~ootprint" is produced on the tur~, as will be re~arred to.
Referring to Figs. 6, 10, and 11, hosel ~ube 36 extends downwardly into the hollow interior o~ the heel portlon of the head and is adapted to receive a shaft 12.
Thu~, the weight of the hosel is concentrated moro direotly behlnd, or alose to, the rear side of ~ront wall 28, near the heel, to contributa to the ball-striking mass o~ the front wall. A1BO~ the hosel cylindrical wall reinforces the ~unction of the front wall, botto~ wall, and heel wall. See al80 rigidizing hosel webbing or : 20 ~illeting ~4, which ~orm8 the corner plats section o~ tha -~.
bottom wall 22. Corner sQction also forms a portion o~ ~ ~
I ~Ith~ dished por~ion of thè bo~om wall recess 164. iWhen ~ ~`
: the eole plats is attached ~o the shell, a weld may be ~ormed along edges 9g and 99a, and 100 and 100~. See Figs. 10 and 11. ~.
In accordance with another important aspect o~
tha invention, a ~ir3t group or ~et o~ narrow, metallic ~:.
dendrite~ ia provided to exten~ rrom the ~ront wall 2 generally r~arwardly ad~acent tha undersido 2~k o~ th~ .
top and upper wall 24~ and integral therewlth~ SQe in ~ `
~'`.,`~'''.'' .. . . . . . . . . . . .,; - .

2~31331 ` ~
the example dandrite~ 118-123 spaced apart in a transverse direction, indicated by arrows 120, the dendrite~ having forward end~ 118~--123a merging into the ~ront wall at it~ ~unction~ with the top wall. Not~ the possiblQ widening of the dendrites as they merge with front wall 2~. This serves the purpose o~ di~tributing impact-pro~uced shock or stress waves from the front wall to the top wall, especially when a ball i8 hit high on ` the front wall or face. Thi in turn ~ervQs to prevent orac~ing and buckling of the thin, metal, top wall 24.
- . ., :, Note that the dendrites are spaced apart, i.e., branch, at intervals of about 1/2 to 3/4 inch; and that the rearward ends o~ the dendrites are trangversely spaced apart. .
The vertical dimen~ion d3 of the dendr~tes lies within the range .050 to .070 inch; and the d2ndrites arQ
gen~rally convex at 125 toward the interior o~ the head, along their lengths, and have concave opposite ~ides at .
126 and 127 (see Fig. 12). In this regard, and as raferred to abova, ~he thicknass o~ the ~ront wall 1 typically ~ubstantially greater than the thic~ness of the :~
,~ lother walla, to ~trengthen it and prevent cracking undsr ~:
high impaat loadsO
~ypical wall approximate thicXnQsse~ ar~: ~ront ::
wall .120 inches (~aximum), ~ol~ plate .050 inche~
(maximum~ ~xcluding pos~iblQ local thiakening pro~cting ~rom ~ront ~ace inter~ection wlth the ~ole pla~e, and top wall .030 inche~. The dimen~i~ns are le~ than ~tandard `;~:
thiaknesse~, allowlng ~or ~ larger head and ~ largar ~oment o~ inertia ~or a given total weight. ThiB ln turn ~-~.
~ 19-- '.. "~ ', ' ' - ~i 3~33~

allow~ a graater ~forgivene~ effectn a~ regards of~-center ball strike~. Reduced thicknesses may bs maintalned despite head extreme enlargemant by casting ths head o~ titanium or titanium alloy, whioh i~ lighter ; 5 than ~teel.
~: Purther, the conform~tion of the dendrites 118-123 ~see Fig. 13) along their lengths, to head interior wall ~hape, contribute~ to shock wave distribution acros~ -: the upper wall 14. Note that wall 14 may be upwardly crowned, i.e., upwardly shallowly convex. The top wall may thQrefore have reduced thickness.
: ~ .. ~
: Al~o provided i8 a second set or group o~ . ~
narrow, metallic dendrites extending generally rearwardly .-.
ad~acent the underside o~ the top wall and integral .~
therewith; ~he second sat al~o including a transversely .~ ;
extendlng dendrite interseoting the generally rearwardly extending dendritei~ of the second ~et. The dendrites of . .
the secon~ ~et are located furthar from th~ head ~ront wall than the ~ir~t set o~ dendrites: tho rearwardly ~ ~ 20 extending~dendrites o~ the second 6et being spaced apart, : or branching, in tran~verse diraotion, thQ vertlcal dlmensions oP!tha second set dendxi~es also being between .0:50 and .100 inch2s. Sea ~or example the ~i~a dendrite~
138-1~2 that have ~an con~igurationt radiating rearw~rdly ~rom di~srent points along tha s~ngl~ transvQrsa dendrite 37 ~paced rearwardly fro~ dendrita~ 118-123.
Dendrites 138-142 extend genarally rearward to merge with the generally curved rear wall 26~ of the ~ead, to dire~t or trans~er ~uah rearward loading to that wall as the dendrites pick up loading ~rom top wall 24~

. ...
- 2~
~ , . . ; . ... .
. .
:, --~.,::.

2 1 ~ ~ 3 3 ~

Se~ Fig. 14.
Dendrites 137-142 have generally the same configuration and dimensions as dendrites 118-123.
Accordingly, they serve the same shock or ~tress WaVQ
transfer-d~3tributing functions, to minimize cracking and bu~kling of the thinned top wall at it~ ~unction at 146 with the rear wall. No~e also that dendrites 137-142 con~orm to top wall shape alsng thQir lengths. See Fig.
14. In addition, the rearward end~ of ~he dendrites 137~
142 turn downwardly and forwardly ad~acent the inner ~ide of rear wall 26a, as seen a~ 13sa in Fig. 14, ~or example. This strengthen~ ths rear wall, allowing ~ ;
reduction in rear wall thicknes~
The dendrite~ pro~ect generally toward thQ ~ ;``.
upwardly di~hed wall~ 162' and 164', ~o that both top and bottom walls ar~ stlffened to transmit shock loading rearwardly, wh~ther the ball strikes the ~ront wall 28 relativ~ly upwardly ther~on, or at a low~r portivn thereo~.
A further important aspect of the invention concerns the provlsion of a gol~ alub head havlng a metal shell de~lning top, bo~tom, front, rear, ~08, and heel wall~, and wherein:
a) the bottom wall ha~ upwardly di~hed wall extQnt, b) thQ upwardly di~hed wall extent defining downward ~acin~ ~urface m~an~ inclined ~orwardly and i;
upwardly relative ~o the haad swing path as th~ botto~ ~ ;
wall engage~ the tur~, ~o that ~ha tur~ moving relat~vely rearwardly engageB tha inclined Bur~acQ mean~ for ,j ~,,r,; ,,~"t~ ,i", ~ ~, ," "~ "" ~ " " , ` ~ " ~ ", ~ " " ~ ;"

2~3~ 3~:~

creating lit force, ac~ing to urge tha bottom wall and the head in an upward direction, whereby drag i8 reduced and more kinetic energy i8 available for trans~er to the ball.
5Further, and as described, the bot~om wall also ; .
has a downward ~acing medial ridge 60 which extends generally forwardly, the dl3hed wall extent preferably ; includlng two dished extents 16~ and 164, respectively, -~
located at oppos1te ~ides o~ the ridge, each o~ the two 10di~hed extent~ da~ining a portion o~ the inclined sur~ac~ ~
means (at the rears o~ dished extents 162 and 164), ~ ~;
whereby upward lift forces are developed at opposite sidès of the ridg~, ~or torsionally balanced upward lift lmparted to the head. ... ~
15Finally, the turf controlling head ~ottom wall ~`
can be formed or cast integrally with ~he remalnder o~
the head, i~dasired, 1.~. 1! it need not be separatQly ~ormed and later welded to a rim defined by a separatQly ca~t head. Such ~oxming may be by a casting or molding 20process employing metallic or non-m~tallic material. ~`~
Further, and as ~hown, ths two rece~ses o~ each ~`
hQad hav~ Bimilar configuration wlth resp~ct to a~
vQrtical plan~ 400 that bisec~ ridge ~0 in a ~ront-to-rear direction relative to the h~ad. See Fiqs. 2 and 7. -25It will also be ~een that eaeh rec~as ~a3 a `~
downward ~acing sur~ace and i8 ~urther characterized in t~at~
1) the rearwardmost extent~ 162~' and 164~l o~ tha downwardly ~acing 30sur~ace~ ~ro inclined ~orwardly and ,. j",.
- 22 ~

;
2 1 3 1 3 3 ~

upwardly relative to the head forward swing path as the head ,'~
bottom wall engages tha tur~ (see : .-Fi~s. 3 and 4), ii) whereby balanced li~t force3 are ;~
~:~ created in reæponse to engagement of -the rearwardmost extents of the ~.
urface~ with the tur~ a~i the head .::
~: i8 swung forwardly along the path, -: .
such lift forces acting to urge the .;.
head bettom wall and the head in an upward direction.
~: The bottom wall and~or the re~t of tha head can ~e =ade o~ materials other than metal, but metal, such aa . I
titaniu~, i~ preferred ~or a very large head. : :
~8 u~ied herein, the word "turf" shall be under~tood ~o mean grass, weeds, sand, mud, an~ other ~ ;
materlal eingageable and displaceable by the botto~i wall .: .:
o~ the haad. ~: "
: ~ 20 : Re~arrlng to Fig. 5, the recesie~ 162' and 164' ~:
have edges 162Q~ and 1649' wh~ch, when vlewed ~ro~ the .
rear o~ th~ head, ar~ upwardly convex. Tha r~arwardiedg ~: 55aa of ~latten~d beveled surface 56 i~ al80 upwardly convex in Fig ~ and located approximately midway botween edge~ 162a~ and 164 i~. SUchi convex adgee extend ini an arcuatQ row, a~ seen in Fig. 5, and de~ine a V-~hap~
Upward lift force vectors appear ~t 190 ~nd 191, ~nd result ~rom engagemsnt of the inclined r~iar portion~ of the incl~ned rear portions o~ theid~hed race~ ~ur~acQs with the tur~, a~ rererred to above. Note that the ` ' :

~ ."';

~ `` 2~313~ ~

. :.
vectors are angled upwardly and toward one anothsr.
Re~erring again to Fig. 5, the head i8 ~urther characterized by tha following~
i) the dished recesses 162 and 164 are located in 8ub8tantially mirror imaged position with respect to a forwardly extendlng, vertical pl~ne 400 bisecting the r1dge 60;
ii) thQ convergent rearward terminu~ o~
dished reces~ rearwardmost extent 162~' ~ i8 intersected by a cusp 210 defined by : angled sur~ace or bevel 56; and the ;: ~ convergent rearward ~erminus of dished reces~ rearwardmost extent 164d' is intersected by a cusp 211 also dc~lned by b~vel- 56. These ¢USp8 are further def~ned by intersection of the bevel with : head convexly rounded or arcuat~ outer bottom sur~ace 213 and intersection of : ~ 20 the bevel wit~ ~h~ ridge rearwardmost andrearwardmo~t divergent extents, ae shown.
r ~ he cu~ps 210 and 211 are substant1ally egu1dlstant ~r~m the head front ~ace 28, whereby the bevel 56 i~ centersd between the rearwardmo3t extenta 162~' and 164 o~ the:recessea;
lii) plane 400 al~o bi~ecta tha ~vel ~o that : cu~p~ 210 and 211 aro located at ~i`
~ub~tantially ~qual di~tanc~ Prv~ khat ~i-planet and the plane 400 ~180 inter~ect ``~
:: . . ',' 24 .

, ; .

`- ` 213~33~
~ : .
the rearwardmost extent 213~ of the head.
The above feature~ also contribute to the ~ -.
balanced li~t ~orce creation discus~ed above.
Re~erring again to Fig. 2, it will be seen that the illustrated very large metal head, when viewed toward . .
the bottom wall, presents a peripheral outline which, at :~
the toa and rear o~ the head, has substantlal 6pacing ~: from the other dished shallow recess. See peripheral outline 300, which at the toa o~ tha head, has 6pacing S
from recess 162; and at the rear of the head ha~ spacing S2 from recess 162. Sl is typically at least about 5/8 ;~
: inch and may preferably be about 3/4 to 7/8 inch; and S2 is at least about 1 inch, and may preferably be about 1 .-.`~ .
to 1-3/8 inch, in the plane in which ~he bottom wall i8 `~
viewed, as in Fig. 2. :~
These ralatively large spacings, provlded ~or a large matal wood head, contribute to strengthenlng a~ ~ `
needQd ~or a very thin wall construction, ~ince the i~
assoaiated wall~ o~ the head have extended convexly 510ping or arcuate extent, i.e., "tumble home'l. SQe walls at 301 associated with Sl, and wall~ a~ 302 :~
a~sociated with S2.
Furthar, the ~pacing S3 between overall perip~eral outline 200 and the rear bevel ~6, as viewed `:
in Fig~ 2, is at lea~t abou~ 3/4 inch, ~or tha very large head ~hown; and ~he head surfaae 213c a~so¢lated with 83 ~ ~.
~lope~ upwardly and outwardly ~rom the bevQl 56 toward outline 300.
Further, ~or the very larga head shown, the peripheral outline 300 encompas~s an area ~, as viewed - 25 - :
~ .

2:13~33~

in Flg. 2; and the dished reces~ 162 and lÇ4, ridge 60, and bevel 56 define an outline encompassing an area B, where: A > 1.6 B, thereby defining an important feature of the very large head; i.e., ths elements 162, 164, 60, and 56 are relatively localized, with re~pect to the overall peripheral size of the head. Preferably, A and B are related as follows: 1.7 ~ A/B < 2Ø Strengthening `~`
of the thin-walled head i~ obtained by providing relatively large areas of tumble home, as referred to at ;
301, 302, 213a, and as also shown at 305 and 306.
Typical head dimensions, a~ seen in Fig. 10, are: -- TH (toe to heel) = about 4-3/8 inches -y FR (front to rear) = about 3-3/4 inches ` ;~-The head top and rear walls have thickness of ~ :
about .055 inch; and the front wall has thickness at its center o~ about .130 inch and tapering toward end portion~ near the heel and toe of thicknes~ about .110 ~
; inch. The ~ole has thiakness of about .070 inch. ~ ;
~etal woods between 1 and 7 ~izes, i.e., with varylng front wall angularities, may bs provided `
incorporating the invention herein; and a ~et o~ such woods may be provided, the invention herein extending to ~uch a ~et. Each head ha~ a center of gravity located at ~`
approximately 42~ to 50% oP the head height, as measured . . .
upwardly ~rom the lowermo~t head ~ur~ace to the uppermo~t head sur~ace ! vlewed from th~ ~ront of the headc ~he content~ of all application~ o~ whloh the pre~ent applicatlon i~ a continuation, or a continuation :`~
in-part, are incorporated here~n, by re~erence.
~,~.. ..
., ;......
.. . - . ~
- 26 - ~
, ~ , : . .

;; `' ;~:`~"

Claims (35)

1. A golf club head comprising a shell having toe and heel portions, a rear wall, a front wall defining a ball-striking face, and top and bottom walls, said bottom wall characterized as having a medial ridge, and as forming two dished shallow recesses, one recess between the ridge and the heel portion, and the other recess between the ridge and the toe portion, said recesses spaced rearwardly from said front wall, the one recess having an arcuate peripheral edge generally convex toward said heel portion, and the other recess having an arcuate peripheral edge generally convex toward the toe portion, said recesses being located in substantially mirror imaged positions with respect to a forwardly extending vertical plane bisecting said ridge, the head, when viewed toward said bottom wall, presenting a peripheral outline which, at the toe and rear of the head, has substantial spacing from said other dished shallow recess.

2. The club head of claim 1 wherein said spacing between said peripheral outline at the toe and said other dished recess is at least about 5/8 inch.

3. The club head of claim 1 wherein said spacing between said outline at the head rear and said other dished recess is at least about 1 inch.

4. The club head of claim 1 wherein said medial ridge increases in width toward said front wall and between forward extents of said recesses.

5. The club head of claim 1 wherein said bottom wall has a bevel that extends at a rearwardly and upwardly extending angle, beyond rearward extent of said ridge, and between rearward extents of aid recesses.

6. The club head of claim 5 wherein said spacing between said outline at the head rear and said bevel, as viewed toward the head bottom wall, is at least about 3/4 inch.

7. The club head of claim 1 wherein the head has downwardly facing surfaces which slope upwardly and outwardly from said other dished recess toward said peripheral outline, as viewed toward the head bottom wall.

8. The club head of claim 5 wherein said peripheral outline encompasses an area A, and said dished recesses, ridge and bevel define an area B, when viewed toward the bottom wall of the head, and where A > 1.6B.

9. The club head of claim 8 where 1.7 < A/B < 2.0

10. The club head of claim 1 wherein said recesses have downward facing surfaces with shallow upwardly dished configuration.

11. The club head of claim 1 wherein said bottom wall is in part defined by a sole plate having a peripheral edge rigidly connected to the bounding edge of an opening defined by said bottom wall, whereby the sole plate closes said opening, said ridge and recesses being in part defined by the sole plate.

12. The club head of claim 1 wherein said recesses have surfaces that merge in arcuate relation with opposite sides of said ridge.

13. The club had of claim 1 wherein aid front wall has lowermost U-shaped configuration, forwardly of said ridge and recesses.

14. The club head of claim 1 having a substantially continuous, hollow, metallic tube extending within the shell of the heel portion and from proximate the shell top wall to proximate the shell bottom wall, said tube having a bore to receive a club shaft, said bore aligned with said one shallow recess.

15. The club head of claim 10 wherein said downward facing surfaces are concave in front-to-rear directions.

16. The club head of claim 15 wherein said downward facing surfaces are also concave in directions between the heel and toe.

17. The club head of claim 5 wherein said bottom wall includes a sole plate peripherally connected to a shell rim defining a bottom opening, said sole plate defining major extents of said shallow recesses.

18. The club head of claim 5 wherein said bottom wall includes a sole plate peripherally connected to a shell rim defining a bottom opening, said sole plate defining major extents of said shallow recesses, said sole plate also defining said ridge and said bevel.

19. The club head of claim 14 wherein said bottom wall includes a sole plate peripherally connected to a shell rim defining a bottom opening, said sole plate defining major extents of said shallow recesses, said shell defining a bottom wall corner plate section integral with said tube, said sole plate also connected to said corner plate section, said corner plate section forming a portion of said one shallow recess between said ridge and heel portion.

20. The club head of claim 1 including a first group of narrow, metallic, shock wave distributing dendrites extending from said front wall generally rearwardly adjacent the underside of the shell top wall and integral therewith, said dendrites projecting toward said two shallow recesses.

21. The club head of claim 20 including a second group of dendrites integral with said top wall and which are spaced apart, and which extend generally rearwardly to merge rearwardly and downwardly with a rear wall defined by the shell to transfer rearward loading from said top wall in response to front wall impact with a golf ball, said second group of dendrites also projecting toward said two shallow recesses.

22. The club head of claim 21 wherein the dendrites of each group are spaced apart in a toe-to-heel direction.

23. A golf club head having a metal shell defining top, bottom, front, rear, toe, and heel walls, and including a) dendrites integral with the inner sides of said top and rear walls, and b) the bottom wall having two upwardly dished wall sections projecting toward the dendrites integral with the top wall, and spaced between the heel and toe, one dished wall section defining one recess relatively closer to the toe and the other dished wall section defining another recess relatively closer to the heel, c) the head, when viewed toward said bottom wall, presenting a peripheral outline which, at the toe and rear of the head, has substantial spacing from said other dished shallow recess.

24. A club head of claim 1 wherein the ridge is downwardly convex rearwardly of said front wall and co-acts with said recesses during a club stroke to direct the turf toward and into the recesses, the recesses having surfaces inclined forwardly and upwardly to be engaged by the turf moving relatively rearwardly, for creating lift forces at opposite sides of the ridge, urging the bottom wall and head in an upward direction.

25. The head of claim 5 wherein the head has a center of gravity located at approximately 42% to 50%
of the head height, as measured upwardly from the lowermost head surface to the uppermost head surface, viewed from the front of the head.

26. The club head of claim 1 which is metallic and comprises titanium.

27. The club head of claim 8 which is metallic and consists essentially of titanium.

28. The club head of claim 26 wherein at least one of said head walls has minimum thickness less than about .060 inch.

29. The club head of claim 1 wherein said top wall has thickness of about .055 inch, and said front wall has minimum thickness less than about .130 to .110 inch.

30. The golf club head comprising a metallic shall having toe and heel portions, a rear wall, a front wall defining a ball stoking face, and top and bottom walls, the bottom wall characterized as having localized undulant and angled surfaces delineated within a first peripheral outline for turf engagement and for urging the head upwardly in response to turf engagement, the head, when viewed toward said bottom wall, presenting a second peripheral overall outline having substantial spacing from said first peripheral outline at least toward said toe and toward the club rear, the club head shell sloping arcuately upwardly and outwardly between said first and second outline.

31. The head of claim 30 wherein said first peripheral outline encompasses an area B, and said second peripheral outline encompasses an area A, where A > 1.6 B.

32. The head of claim 31 wherein 1.7 < A/B < 2Ø

33. The head of claim 1 having a center of gravity located at approximately 42% to 50% of the head height, as measured upwardly from the lowermost head surface to the uppermost head surface, viewed from the front of the head.

34. A set of golf club heads, each head having a configuration, as defined in claim 1.

35. The set of heads, as defined in claim 34, wherein each head has a center of gravity located at approximately 42% to 50% of the head height, as measured upwardly from the lowermost head surface to the uppermost head surface, viewed from the front of the head.