AU655647B2

AU655647B2 - Wood type golf clubs

Info

Publication number: AU655647B2
Application number: AU20727/92A
Authority: AU
Inventors: Anthony D. Serrano; John A. Solheim
Original assignee: Karsten Manufacturing Corp
Current assignee: Karsten Manufacturing Corp
Priority date: 1992-02-21
Filing date: 1992-07-31
Publication date: 1995-01-05
Anticipated expiration: 2012-07-31
Also published as: CA2072706C; DE69213919T2; EP0556502A1; ZA924839B; JPH0815500B2; CA2072706A1; ES2093203T3; DE69213919D1; AU2072792A; KR930017590A; JPH06105937A; EP0556502B1; KR0167569B1

Description

65564 7

AUSTRALIA

PATENTS ACT 1990 COMPLETrE SPECIFICAT[ON NAME OF APPLICANT(S): Karsten Manufacturing Corporation ADDRESS FOR SERVICE: DAVIES COLLISON CAVE Patent Attorneys S -7 L INVENTION TiTLE: :Wood type golf clubs :9 The following statement is a full description of this invention, including the best method of performing it known to me/us:- BACKGROUND OF THE INVENTION FIELD OF THE INVENTION This invention relates generally to golf clubs and, in particular, to a type of golf club commonly referred to as "woods" which have an enlarged head attached to one end of an elongated shaft.

DESCRIPTION OF THE PRIOR ART S, A full set of golf clubs generally consists of a correlated set of wood type clubs and a correlated set of iron type clubs. A conventional wood type golf club is disclosed in U. S. Patent No. 3,625,518 while conventional iron type golf clubs are disclosed in U. S. Patent No. 3,655,188. Wood type golf clubs have heads constructed of materials such as wood, metal and plastic. Iron type golf clubs have heads usually made of metal.

Referring to Figs. 1 3, a wood type golf club according to the prior art has an enlarged head 10 including a specially shaped body 12 preferably formed of wood with a hosel 14 which re:o!ives and is attached to one end of an elongated >haft 16. A grip (not shown) is moulted on the other end of the shaft 16 so that head 10 may be swung in an arc to contact a golf ball resting on a tee or on the ground. An insert 18 preferably formed of a resin material is centrally mounted in a face portion 12a of :le body 12, and a metallic sole plate 20 is 1A attached to a bottom portion 12b of the body 12 by a plurality of screws 22 and/or epoxy. The sole plate 20 has an arcuate notch 24 at one end and a straight edge 26 at the other end.

When the sole plate is attached to the body 12, the notch 24 and the edge 26 are engaged with an arcuate shoulder 28 and a straight shoulder 30, respectively, formed on the body 12. The sole plate 20 also has a curved side 32 and a relatively straight side 34. Shoulder 30 is located in a heel lOa of the head 10 while shoulder 28 is located in a toe lOb of the head tt Vo.. When making a wood type golf club that is designated as a driver or a No. 1 wood, a hole 36 shown in Fig. 1 is bored in the bottom of the driver body 12 to remove weight therefrom so that the finished golf club will have a desired swingweight.

Swingweight is generally defined as a measurement of a golf club's weight distribution about a point which is at a 'ttc specified distance from the grip end of the golf club. Hole Vitt 36 is necessary because the body 12 in a driver is larger and heavier than in other golf clubs in a correlated set. When I CI making other wood type golf clubs with relatively smaller heads those designated as Nos. 3, 5 and 7 woods), holes 38, shown in Fig. 2 are bored in the body 12 and then filled with weighted inserts 39, 41 made of lead or brass in order to provide finished golf clubs of desired swingweights. In a correlated set of wood type golf clubs according to the prior art including for example Nos. 1, 3, 5 and 7 woods, the sole plates 20 on the Nos. 3, 5 and 7 have been made of a 2 1 i -3heavyweight material such as brass whereas the sole plate 20 oi, the No. 1 wood has been made of a lightweight material such as aluminum. This helps to reduce, but not eliminate, the additional weight that must be added to the body 12 in the Nos. 3, 5 and 7 woods by using the weighted inserts 39, 41.

The golf club shown in Figs. 1 3 has the face portion 12a of the body 12 arranged for contacting a golf ball. Located on the face portion 12a is a centre point 11 i o known as a "sweet spot" which is in general alignment with the centre of gravity of the

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f 10 head 10. If the head 10 impacts a golf ball at precisely the sweet spot 11 during a golf swing, maximum energy will be transferred from the heard 10 and the golf ball will travel along its intended path. If the club head 10 impacts a golf ball at off-centre points Sla, lb which are also located on the face portion 12a but in the heel and toe 10a, a •of the head 10, twisting movements of the head 10 will occur resulting in less than maximum energy being transferred from the head 10 and deviation of the golf ball from its intended path of travel. Such deviation of the golf ball is generally referred to as a a ."slice" or a "fade" when impacting the head 10 at point 1 la and as a "hook" or a "draw" when impacting the head 10 at point 1 lb.

According to one aspect of the present invention there is provided a wood type golf club comprising: a shafc; a head attached to one end of said shaft, said head I including a heel, a tov., and a body having a face portion arranged for impacting a golf ball; a sole plate attached to a bottom portion of said body, said sole plate having a weight and a substantially circular cavity formed in a centre section thereof which T 25 decreases the sole plate weight in said centre section while increasing the sole plate p:\wpdocs\5s\500210.spo\sb -4weight distribution ratio between perimeter sections thereof and said centre section, said cavity having an outer edge extending in a generally circular path, said sole plate also having a ledge circumscribing said cavity and contacting said bottom portion of said body, said outer edge of said cavity defining an inner extremity of said ledge with said ledge extending outwardly in all directions from said outer edge of said cavity and having an upper surface which is elevated above a bottom surface of said cavity; and said perimeter sections of said sole plate including a heel perimeter section located adjacent said heel of said head, a toe perimeter section located adjacent said toe of said 0 head, a forward central perimeter section located forwardly of said cavity between said heel and toe sections, and a rearward perimeter central section located rearwardly of said cavity between said heel and toe sections, said ledge extending through all of said sole plate perimeter sections.

Preferably the heel section of the sole plate concentrates a first proportion of the sole plate weight in the heel of the head, the toe section of the sole plate concentrating a second proportion of the sole plate weight in the toe of the head and the first and "second proportions together constitute more than 50% of the majority of the sole plate weight.

Preferably the sole plate has an interior s, !ace and an ext -rior surface and the cavity is formed in the interior surface of the sole plate.

Preferably the cavity has inclined walls which form an acute angle with a bottom surface of the body.

The cavity is preferably located generally intermediate the heel and the toe of i 'A4 p:\wpdocs\nis\5002 I0.spc\sb 0 the head. Preferably the body is formed of wood and the sole plate made of metal.

The cavity maybe formed in an interior surface of the sole plate and the bottom surface thereof is spaced from a bottom surface of the body when the sole plate is attached to the bottom portion of the body.

Preferably the sole plate heel perimeter section has a generally triangular shape in plan view and the sole plate toe perimeter section and sole plate forward and rearward central perimeter sections are generally C-shaped in plan view.

S.

S S Preferred embodiments of the invention will herein after be described with reference with to the accompanying drawings in which: Fig. 1 is an exploded perspective view of a golf club head according to the prior art; p:\wpdocs\mns\500210.spe\sb

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Fig. 2 is an exploded perspective view of another golf club head according to the prior art; Fig. 3 is a bottom perspective view of the prior art golf club heads shown in Fi,, 1 and 2 taken when they are assembled; Fig. 4 is an exploded perspective view of a golf club head according to the preferred embodiment of the present invention; Fig. 5 is a bottom perspective view of the golf club head shown in Fig. 4 taken when it is fully assembled; Fig. 6 is a vertical cross-sectional view of the golf club head shown in Fig. 5; and Fig. 7 is a top plan view of a sole plate used in the golf club head of Figs. 4 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT i Referring to Fig. 4, a wood type golf club according to the preferred embodiment of the present invention includes an enlarged head 42 having a specially shaped body 44 and a sole plate 46 which is attached to a bottom portion 44a of the body 44 by conventional means such as a plurality of screws 48 and/or epoxy. The body bottom portion 44a has a bottom surface of compound curvature. An insert 50 preferably formed of a resin material is mounted in a face portion 44b of the body 44.

The face portion 44b is arranged for impacting a golf ball.

The body 44 includes a neck or hosel 52 with a bore 54 (Fig. 6) therethrough for receiving and attachment to one end of an S6 1 elongated shaft 56. Mounted on the other end of the shaft 56 is a grip (not shown). In the preferred embodiment of the head 42, body 44 is formed of wood and sole plate 46 is made of metal. Alternatively, body 44 could be made of other suitable materials such as plastic or metal.

If the head 42 is manufactured for use on a wood type golf club designated as a driver No. 1 wood) with the body 44 made of wood, a hole 58 is bored in the bottom of the body 44 to remove weight therefrom so that when the sole plate 46 is attached, the head 42 will have a desired total head weight which is used in calculating a swingweight for the golf club.

As previously stated swingweight is generally defined as a measurement of a golf club's weight distribution about a point which is at a specified distance from the grip end of the golf t club. If the head 42 is manufactured for use on a wood type golf club such as those designated as a No. 3, 5 or 7 wood with the body 44 made of wood, no weight is removed from the body 44 before attachment of the sole plate 46. Therefore, in all woods except the driver such as the Nos. 3, 5 and 7 woods, the t«*C boring of hole 58 is not required.

The swingweight for the golf club shown in Figs. 4 7 is determined by taking into account the total head weight of the head 42 and other factors such as the weight and length of the shaft 56. The body 44 and the sole plate 46 each have an individual weight which is less than the total head weight of the head 42. When making the head 42, the body 44 is weighed to insure that its weight is within a preselectad range, and 7 then the sole plate 46 is selected from a plurality of sole plates which are formed of identical material aluminum) but have different weights so that the weight of the selected sole plate 46 is equal to the total head weight less the weight of the body 44. Instead of using additional weights weighted inserts 39, 41) in the body 44 to compensate for deficiencies in the total head weight of the head 42 as in prior art golf clubs, the weight of the sole plate 46 is increased by merely selecting a heavier sole plate.

As seen in Figs. 4, 6, and 7, the sole plate 46 has a substantially circular cavity 60 formed in its interior surface and located generally intermediate a heel 42a and a toe 42b of the club head 42. The cavity 60 has inclined side walls and a relatively flat bottom wall. The inclined side walls of S. the cavity 60 form an acute angle with the bottom surface of t.

I the body 44 which is adjacent the hole 58 as best shown in Fig.

Alternatively, the cavity 60 could be of a different shape such as an oval. T1,= purpose of cavity 60 is to concentrate a majority of the weight of the sole plate 46 in perimeter sections 46a, 46b, 46c and 46d (Fig. 7) of the sole plate 46 by reducing the weight of the sole plate 46 in its center section 46e. Thus, the cavity 60 in the sole plate 46 results in perimeter weighting of the club head 42. An advantage of this perimeter weighting is improved weight distribution in the heel and toe 42a, 42b of the club head 42 which causes the club head 4Z to resist twisting movements in directions indicated by arrow 62 in tig. 5 when impacting a golf ball at 8a SI V /1 off-center points 43a, 43b located on the body face portion 44b in the heel and toe 42a, 42b of the head 42. No such twisting movements of the club head 42 occur when impacting a golf ball at a center point or "sweet spot" 43 which is also located on the body face portion 44b.

The sole plate 46 has an extended heel section 46a and an extended toe section 46b. The extended heel section 46a concentrates a first proportion of the perimeter weight of the sole plate 46 in the heel 42a of the club head 42 while the extended toe section 46b c)ncentrates a second proportion of the sole plat perimeter weight in the club head toe 42b. When combined, these first and second perimeter weight proportions f4constitute more than 50 percent of the perimeter weight of the sole plate 46.

It should be noted that the sole plate 46 does not have a notch such as notch 24 in sole plate 20 or a straight edge such ',ca s straight edge 26 on sole plate 20. Therefore, the sole t plate 46 is significantly heavier at its ends than the sole plate 20 thereby resulting in the club head 42 having increased heel and toe weighting when compared with the club head Due to the cavity 60, sole plate 46 has significantly less weight at its center than the sole plate 20. This also contributes to the improved heel and toe weighting of the club head 42.

It will be understood that when the club head 42 is constructed for use on a golf club designated as a No. 1 wood, the sole plate 46 will weigh less than when the club head 42 is 9 6, i> J

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constructed for use on a golf club designated as a No. 3, or 7 wood. This is because in a No. 1 wood, the body 44 weighs more than in the other woods. In all of the woods, the combined weights of the body 44 and the sole plate 46 must be within a preselected range in order to provide a desired swingweight.

In a correlated set of golf clubs, the diameter and the depth of the cavity 60 may be changed in order to increase ,r ii decrease the weight of the sole plate 46. For example in a No.

wood, the cavity 60 has a smaller diameter and is shallower Sthai in a No. 3 wood which results in the sole plate weight jl F .being greater in the No. 5 wood.

The reference numerals in the following claims do not in any way limit the scope of the respective claims.

Claims

1. A wood type golf club comprising: a shaft; a head attached to one end of said shaft, said head including a heel, a toe, and a body having a face portion arranged for impacting a golf ball; a sole plate attached to a bottom portion of said body, said sole plate having a weight and a substantially circular cavity formed in a centre section thereof which decreases the sole plate weight in said centre section while increasing the sole plate weight distribution ratio between perimeter sections thereofand said centre section, said cavity having an outer edge extending in a generally circular path, said sole plate also having a ledge circumscribing said cavity and contacting said bottom portion of said body, said outer edge of said cavity defining an inner extremity of said ledge with said ledge extending outwardly ii all directions from said outer edge of said cavity and having an upper surface which is elevated above a bottom surface of said cavity; and said perimeter sections of said sole plate including a heel perimeter section ,I o located adjacent said heel of said head, a toe perimeter section located adjacent said toe of said head, a forward central perimeter section located forwardly of said cavity t 1 between said heel and toe sections, and a rearward perimeter central section located rearwardly of said cavity between said heel and toe sections, said ledge extending 20 through all of said sole plate perimeter sections.

2. The wood type golf club of claim 1, wherein: said heel section of said sole plate concentrate, a first proportion of the sole plate weight in said heel of said head; said toe section of said sole plate concentrates a second proportion of the sole plate weight in said toe of said head; and said first and second proportions together constitute more than 50 percent of the sele plate weight.

3. The wood type golf club of claim 1, or claim 2 wherein: said sole plate has an interior surface and an exterior surface; and said cavity is formed in the anterior surface of said sole plate. i

4. The wood type golf club of claim 3, wherein said cavity has inclined side walls which form an acute angle with bottom surface of said body.

5. The wood type golf club of any preceding claim, wherein said cavity is located p:\wpdoc\rns\5002 O.spc\sb I -12- generally intermediate sad heel and said toe of said head.

6. The wood type of golf club of any preceding claim, wherein said body is formed of wood, and wherein said sole plate is made of metal.

7. The wood type golf club of any preceding claim wherein said cavity is formed in an anterior surface of said sole plate and wherein said bottom surface thereof is spaced from a bottom surface of said body when said sole plate is attached to said bottom portion of said body.

8. The wood type golf club of any preceding claim, wherein said sole plate heel perimeter section has a generally triangular shape in plan view, and wherein said sole plate toe perimeter section and said sole plate forward and rearward central perimeter c sections are each generally C-shaped in plan view.

9. A golf club substantially as hereinbefore described with reference to the accompanying drawings. S 15 DATED THIS 23RD DAY of JUNE 1994 Karsten Manufacturing Corporation by its patent attorneys DAVIES COLLISON CAVE I i. p:\wpdocs\nis\500210.spe\sb I ABSTRACT A wood type golf club includes a head (42) attached to one end of a shaft The head has a total head weight which is used in calculating a swingweight for the golf club. A face portion (46b) on a body (44) in the club head (42) is arranged for impacting a golf ball, and a sole plate (46) is attached to a bottom portion (44a) of the club head In order to resist twisting movements of the club head (42) when impacting a golf ball at off-center points (43a, 43b) located on the body face portion (44b), the sole plate (46) has a majority of its Sweight concentrated around its perimeter (46a, 46b, 46c, 46d) by providing a cavity (60) in an interior surface of the sole plate The body (44) and the sole plate (46) each have an individual weight which is less than the total head weight. The sole plate (46) is selected from a plurality of sole plates formed of identical material but having different weights. The C weight of the selected sole plate (46) is the total head weight minus the weight of the body (44) thereby eliminating the use SItt of additional weighted inserts (39, 41) in the body (44). r t C f