WO1998028051A1

WO1998028051A1 - Golf club

Info

Publication number: WO1998028051A1
Application number: PCT/AU1997/000869
Authority: WO
Inventors: John Arthur Dalton; Charles Anthony Micklewright
Original assignee: Dalton John A; Charles Anthony Micklewright
Priority date: 1996-12-24
Filing date: 1997-12-22
Publication date: 1998-07-02

Abstract

An iron or wood type golf club comprises a head, a grip, and a shaft, the axis of the grip and at least a majority of the axis of the shaft passing within 1 inch of either the centre of the sweet spot or the centre of mass of the head. The golf club also has a front face, a rear, an inner side and an outer side, the front face providing a striking face for a ball, and the shaft being connected to the head via the top of the head at least 0.65 inches from the inner side of the head.

Description

Golf Club

This invention relates to the design of a golf club head attached to a shaft and a grip which is used for striking a golf ball anywhere between a teeing ground and a putting green; generally referred to as a "golf club". The principle skill in accurate striking of a golf ball is to contact correctly the ball on that point on the striking face of the club head adjacent the centre of mass of the head; generally referred to as the "sweet spot".

Presently known golf clubs are of the common "blade" shape, or "peripherally weighted" head shape.

It has generally been tested and agreed that it is desirable for the club head to strike the ball at the "sweet spot", which is accepted by technologists in the industry as having a larger area if the peripheral weighting head design is used as opposed to the common "blade "shape. The iron head shown in US Patent No. D276644 is considered to be the most improved design yet devised to provide an iron golf head with an enlarged "sweet spot".

It will be appreciated that considerable skill is required to swing accurately a golf club so that the club head makes contact with the ball at the "sweet spot", or centre of the mass of the club head at a forward portion on the striking face of the club.

Generally, when one hears the term moment of inertia in connection with golf clubs, the expression refers to the club head. In an attempt to increase the moment of inertia of the club head, heel and toe weighting is incorporated in iron heads, and the size or volume of metal wood heads is increased. In this context, the moment of inertia represents the resistance of the club head to angular deflection when contact with the ball is made at some point other than the centre of percussion, or "sweet spot", of the club head.

The moment of inertia of the golf club as a whole is an important consideration. It is a factor which limits the amount of clubhead speed a player can develop.

Initial golf ball velocity and resulting distance is a direct function of clubhead speed. Factors which directly affect the moment of inertia of the golf club are the clubhead weight, shaft length and shaft weight. Shaft length and clubhead weight have the greatest effect on the overall moment of inertia. By definition, moment of inertia is the sum of the products of the mass and square of the perpendicular distance to the axis of rotation for each particle rotating about an axis.

It will be appreciated that the mass and weight of a golf head are not the same. The weight of an object is the downward force of the earth's gravity acting on the mass of the object, which in this case is the golf head. The relationship between weight and mass is defined as: Mass multiplied by g, where g is the gravitational constant.

It will also be appreciated that when considering the design of present day golf clubs it will be seen that the object at the end of the golf shaft, called the head, is so attached as to be angularly positioned in relation to the axis of the grip and shaft and thereby does not offer the benefit of "resistance to twist" when the golf club is swung in the normal, or conventional way of attempting to hit, or strike a golf ball on the "sweet spot" of the golf head. This is clearly described and explained in articles written by Charles W. Vigor of Chuck Vigor Golf, Rochester Hills, Michigan, in the Professional Clubmakers' Society Journal dated March/ April 1996 and also by Leon Z. Seltzer. Research Physicist, Goldwin Golf Inc., in the PCs Journals dated July /August and September/October 1995.

It is an object of this invention to provide a golf club with a head so designed as to assist the player to more easily strike the ball at the "sweet spot".

It is also an object of this invention to assist the golfer to effect a golf swing with an improved golf club so that the moment of inertia, or resistance to twisting of the club during the swing, will enable the golfer to deliver the striking face of the golf club square to the intended direction of the ball and strike the "sweet spot" more easily, and thereby propel the golf ball more accurately in the intended direction chosen by the golf player.

It will be appreciated that present day golf clubs are designed in such a way as to create a turning motion of the head around the shaft when the golf club is swung, and this tendency to twist is due to centrifugal forces created by the head of the golf club being attached at the heel of the clubhead.

In accordance with the invention, an iron or wood type golf club comprises head with a sweet spot and a centre of mass, a grip, and a shaft, where at least a majority of the axis of the shaft lies on an axis which passes within 1 inch of either the centre of the sweet spot or the centre of mass of the head.

Suitably, the whole of the shaft lies on the grip axis, a hossel being provided on the head, which hossel is bent relative to the grip axis.

In accordance with the invention, an iron or wood type golf club comprises a head, a grip, and a shaft, the head having a top, a front face, a rear, an inner "heel" side and an outer "toe" side, the front face providing a striking face for a ball, wherein at least a majority of the shaft lies on an axis which passes at least 0.65 inches from the inner side's outermost extremity.

Such a golf head is so shaped and so attached to the shaft that there is no or very little tendency for the head to want to rotate around the shaft during the golf swing, which is a problem caused by conventional golf heads attached to conventional golf shafts.

The invention described relates to golf irons, or wood clubs, since the method of attachment is such that the axis of the shaft preferably points directly to the centre of the mass of the golf head. It may be further seen that the neck, or hossel, or connecting member of the head may be slightly bent, or positioned, so that the axis of the shaft will preferably point to the "sweet spot" on the striking face.

While there may be different combinations of shafts, club lengths, clubhead weights and clubhead designs, it is an object of this invention to provide at all times a golf club which has balancing due to the design and positioning of the golf head on the end of the shaft at the most suitable position. It is a further object of this invention to provide a golf club which has all the playablility features of a conventional golf club while providing the added benefit of absolute balancing so that during the golf swing, the head of the golf club does not tend to rotate around the shaft, thereby making it much easier for the golfer to strike the ball in the approved manner and also make contact more easily with the golf ball on the "sweet spot" of the striking face while it is square to the intended line of flight of the ball.

The invention suitably provides a golf club having a peripherally weighted golf head which is so attached tot he shaft that the axis of the shaft suitably passes through the centre of mass of the head, or "sweet spot", whichever is desired for the purpose of striking the ball more solidly and more easily than by using a conventional golf club with a head attached to the back end of the "heel" portion of the iron or wood head.

The invention will now be described by way of example with reference to the following drawings in which :-

Figure 1 shows a front view of an iron type golf club in accordance with the invention;

Figure 2 shows a side view of the iron of Figure 1;

Figure 3 shows an enlarged front view of the head of the golf club of Figure 1;

Figure 4 shows a rear view of the head of Figure 3;

Figure 5 shows a side view of the head of Figure 3;

Figure 6 shows another side view of the head of Figure 3;

Figure 7 shows a front view of a head for a wood type golf club in accordance with the invention;

Figure 8 shows a rear view of the head of Figure 7; Figure 9 shows a side view of the head of Figure 7;

Figure 10 shows an alternative head for a wood type golf club in accordance with the invention;

Figure 11 shows another alternative head for a wood type golf club in accordance with the invention;

Figure 12 shows an alternative head for an iron or wood type golf club in accordance with the invention;

Figure 13 shows yet another alternative head for an iron golf club in accordance with the invention;

Figure 14 shows an alternative head for an iron type golf club in accordance with the invention from it's front;

Figure 15 shows the head of Figure 14 from the rear; and

Figure 16 shows an alternative head for a wood type golf club in accordance with the invention.

This invention relates to iron and wood types of golf clubs, but not to putter type golf clubs. In consequence, the invention relates to all golf clubs where the striking face has a loft of at least 7°.

In Figures 1 and 2, a No.5 iron type golf club 2 is shown having a grip 4, shaft 6 and head 10. The head has a top, a bottom forming a sole, an inner side forming a heel, and an outer side forming a toe.

In Figures 3 to 6, the head 10 of the iron of Figures 1 and 2 is shown wherein the head at its top (see 12) has an integral hossel 14 which is connectable via a hole 15 to a golf club shaft (not shown). The hossel 14 is connected to the head 10 at the top (see 12) of the head via a bent portion 16 provided on the hossel.

The head 10 is provided with a striking face 18 which is substantially flat and of substantially uniform shape (as seen from the front view of Figure 3), such shape being preferably a oval shape. The head is also provided with a cavity 20 in the rear 22, and perimeter weighted. The head 10 is also provided with the lower surface 24 being wider and being more weighted than the top surface 26 which is narrower and less weighted, so as to give lift to a ball on hitting.

The hossel 14 is connected to the rest of the head at it's top between the inner side edge 28 of the head and the centre line of the head (see line A in Figures 1, 3 and 4), and in particular at least 0.65 inches from the outermost extremity of the inner side edge 28. Preferably, the hossel 14 is connected to the rest of the head at least 1 inch from the outermost extremity of the inner side edge 28, and more preferably at least 1.25 inches from the outermost extremity of the inner side edge 28.

Suitably the shaft is connected to the top of the head of least 0.75 inches from the inner side's outermost extremity (see 28 in Figure 3 and 46 in Figure 7), or more particularly 0.75 inches from the vertical plane containing the inner side's outermost extremity (which vertical plane is at right angles to the point where the shaft connects the top of the head).

In a preferable arrangement, the hossel 14 is joined to the head 10 whereby the axis of the grip and shaft of the club (see line B in Figures 1 to 6) passes within 1 inch of either the centre of the "sweet spot" (see circle E in Figure 1 and 3), or the centre of mass of the head (or a combination of the latter two features resulting in the axis of the grip and shaft passing between the centre of the "sweet spot" and the centre of mass of the head, which can be referred to as the "optimum point"). Suitably the axis B passes within 0.75 inches, preferably within 0.625 inches, more preferably within 0.5 inches, even more preferably within 0.375 inches, most preferably within 0.25 inches of either the centre of the sweet spot or the centre of mass, and most preferably of all either through the centre of the sweet spot, the centre of mass of the head, or the optimum point. Preferably, the axis B passes at least 0.65 inches from the inner side's outermost extremity 28, more preferably 0.9 inch therefrom, most preferably 1.15 inches therefrom, and best of all 1.5 inches therefrom.

Suitably, the axis B intersects the striking face 18 more than 0.75 inches from the outermost extremity of the side edge 28, and less than 1 inch from the centre line A. Preferably, the axis B intersects the striking face 18 more than 1 inch from the outermost extremity of the side edge 28, and less than 0.5 inches from the centre line A. Most preferably, the axis B intersects the striking face 18 more than 1.5 inches from the outermost extremity of the side edge 28, and less than 0.25 inches from the centre line A, and most preferably intersects the striking face 18 in the centre of the sweet spot E, and on the centre line A itself.

Preferably, the axis B intersects the sole 33 a distance of less than 0.75 inches towards the toe from the centre line A, more preferably less than 0.5 inches therefrom, and most preferably 0.25 inches therefrom.

Advantageously, the axis B intersects the centre line A less than 1 inch above the sole 33, more preferably less than 0.5 inches thereabove, and most preferably in the sweet spot area E.

The head 10 is joined to the hossel 14 slightly offset towards the inner side edge 28 from the centre line A in order to provide the correct lie angle for the club, which lie angle is preferably in the region of 50° to 70°. Preferably, the hossel 14 is joined to the head 10 less than 1.25 from the centre line A, more preferably less than 1 inch therefrom, and most preferably less than 0.75 inches therefrom.

Suitably, the axis B intersects the striking face 18 less than 0.5 inches (more suitably less than 0.2 inches) from the horizontal plane including the forwardmost edge of the striking face 18 (see distance F in Figure 5).

Suitably, a front insert 30 of metal (e.g. titanium) or plastics material (or composite thereof) is provided, and a rear insert 32 of absorption material is provided. Details regarding the front and rear inserts can be ascertained from PCT Patent Publication No. WO93/ 10865, the subject matter of which is incorporated herein by way of reference.

A multi-lie sole arrangement 33 can also be provided comprising an inner sloped surface 34, a middle flat surface 36, and an outer sloped surface 38, the centre of the sole (and thus the centre of the middle flat surface 36) being preferably on the centre line A of the club. Further details regarding the multi-lie sole arrangement can be ascertained from GB Patent Publication No. 2286130, the subject matter of which is incorporated herein by way of reference.

The iron 2 of Figures 1 to 6 has a head 10 which is substantially balanced about the axis B. Preferably, the head 10 is balanced so as to have an unbalanced weight of less than 7.5 oz, more preferably less than 5.5 oz, even more preferably less than 3.5 oz, and most preferably less than 1.5 oz, and if possible perfectly balanced so that the unbalanced weight is zero.

Suitably, the head 10 is arranged such that at least 35% of the weight of the head is balanced, more preferably at least 55 % , even more preferably at least 75 % , most preferably at least 95%, and best of all 100%.

The head 10 is face balanced, in other words the striking face of the club faces up when held level proving the massive weight is placed directly behind the point of impact with the golf ball and slightly forward of the centre of gravity. This provides the advantage of resisting any tendency to twist in the case of off-centre hits, which would not be the case if the club was capable of unhindered rotation about the longitudinal axis of the club.

The feature of the hossel 14 connecting the top of the head 10 of an iron type golf club can be provide for all irons in a golf set, ranging from a No. 1 iron to a sandwedge.

Similarly the idea of attaching the hossel directly to the top of a head can be adapted for "wood" type golf clubs as shown in Figures 7 to 9 which "wood" type golf clubs are made of metal. In Figures 7 to 9, a head 40 for a wood type golf club is shown having a hossel 42 which is connected to the top of the wood (see 44) between the centre-line of the wood (see line C in Figures 7 and 8) and the inner side 46 thereof. The hossel 42 is provided with a hole 47 in which the shaft is connected to the head 40. The head 40 is in the form of a hollow shell (preferably foam filled) and has a front face 48 which is substantially flat and forms the striking area. The front face is thicker than the rear wall, lower wall 52 and upper wall 54 of the head. The head 40 is also peripherally weighted around its front face.

In a preferable arrangement, the hossel 42 is joined to the head 40 whereby the axis of the grip and shaft of the club (see line D in Figures 7 to 9) passes within 1 inch of either the centre of the "sweet spot" (see circle E in Figure 7) or the centre of mass of the head (or a combination of the latter two features resulting in the axis of the grip and shaft passing between the centre of the "sweet spot" and the centre of mass of the head, which can be referred to as the "optimum point").

Preferably, the axis D passes within 0.75 inches, and even more preferably within 0.5 inches of either the centre of the sweet spot or the centre of mass of the head.

Suitably, the axis D passes at least 0.65 inches from the inner side's outermost extremity 46, more preferably 0.85 inches therefrom, most preferably 1.05 inches therefrom, and best of all 1.3 inches therefrom.

The head 40 is provided with a striking face 48 of substantially uniform shape (as seen from the front view of Figure 7), such shape being preferably an oval shape.

The head 40 is joined to the hossel 42 slightly offset towards the inner side edge 46 from the centre line C in order to provide the correct lie angle for the club, which lie angle is preferably in the region of 45° to 70°. Preferably, the hossel 42 is joined to the head 40 less than 1.25 inches from the centre line C, more preferably less than 1 inch therefrom, and most preferably 0.75 inches therefrom.

Preferably, the axis D intersects the sole a distance of less than 0.75 inches towards the toe from the centre line C, more preferably less than 0.5 inches therefrom, and most preferably less than 0.25 inches therefrom.

Advantageously, the axis D intersects the centre line C less than 1 inch above the sole, more preferably 0.5 inches thereabove, and most preferably directly behind the sweet spot area E.

Suitably, the hossel 42 is connected to the rest of the head between the inner side edge 46 of the head and the centre line C of the head, and at least 0.75 inches from the outermost extremity of the inner side edge. Preferably, the hossel 42 is connected to the rest of the head at least 1 inch from the outermost extremity of the inner side edge 46, and more preferably at least 1.25 inches from the outermost extremity of the inner side edge 46.

The wood of Figures 7 to 9 has a head 40 which is substantially balanced about the axis D. Preferably, the head 40 is balanced so as to have an unbalanced weight of less than 5.5 oz, more preferably less than 4oz, even more preferably 2.5 oz, and most preferably less than 1 oz, and if possible perfectly balanced so that the unbalanced weight is zero.

Suitably, the head 40 is arranged such that at least 35% of the weight of the head is balanced, more preferably at least 55%, even more preferably at least 75%, most preferably at least 95%, and best of all 100%.

In Figure 10, an alternative arrangement of wood 70 is shown where no hossel is provided, rather a sleeve 72 forming a hole is integrally provided in the top part of the body of the head such that the shaft of a golf club can be inserted directly into the head. The base of the sleeve 72 is also preferably connected to the bottom part of the body of the head (i.e. sole) to strengthen the sleeve 72.

The hole 72 in the wood of Figure 10 is angled in the head such that the shaft extends out of the head to form the correct lie angle for the wood.

In Figure 11, another alternative wood 80 is shown where the front face 82 of the wood directly joins the base (see 84) of the hossel 86. The heads of the woods of Figures 7 to 11 is face balanced, in other words the striking face of the club faces up when held level proving the massive weight is placed directly behind the point of impact with the golf ball and slightly forward of the centre of gravity. This provides the advantage of resisting any tendency to twist in the case of off-centre hits, which would not be the case if the club was capable of unhindered rotation about the longitudinal axis of the club.

In Figure 12, a club 90 (iron or wood) is shown where instead of the shaft 92 extending along the same axis as the grip 94, such extends from the grip bottom end 96 directly to the top of the head (see 98) via a hossel 99 such that the shaft 92 stretches out at a very slight angle (1° or 2°) to the grip axis. As a result, there is no need for the bend 16 in the hossel as shown in the Figure 1 to 6 embodiment, where the club is provided with a shaft which lies on the grip axis passing through the "optimum point".

In another embodiment of iron type golf club (not shown), instead of a hossel, a hole can be provided in the head into which a shaft can be directly inserted, similar to that as shown for the wood of Figure 10.

In Figure 13, another modification of iron type golf club is shown, the hossel 100 being connected to the middle of the rear 102 of the head 104, instead of at the top end of the head in the Figure 1 to 6 embodiment.

The iron shown in Figures 14 and 15 is provided with a substantially upright line on the front face of their head, the line passing through the centre of the sweet spot, and substantially equidistant from the toe and heel. The line aids the user of the club to hit the ball correctly with the sweet spot of the head, since as the shaft lies on an axis passing through the sweet spot, the shaft partly obscures the golf ball when a user addresses the golf ball with the iron.

The line also extends over the top of the head to aid visibility of the line on the front face. The front of the face is also provided with a circular mark so as to aid the user to position the club head correctly relative to the ball. In particular, the club head is positioned so that the upper part of the circular mark appears to the user to hug from a short distance the rear semi-circular outerline of the ball.

The front face is also provided with a series of straight score lines from the toe to the heel, so as to impart side spin to achieve a hook/slice effect when required.

In the iron of Figures 14 and 15, the hossel is not connected to the top of the head via the shortest distance between the bottom of the shaft and top of the head as in the irons of Figures 1 to 6, rather the hossel is connected to the top of the head nearer the inner side portion of the head. In particular, the hossel extends at an angle (between 15° and 60° - preferably 30°) to the shortest line which extends between the bottom of the shaft and top of the head.

The head of the wood shown in Figure 16 is provided with an arrow head mark on it's top surface so as to aid the user where to line up a golf ball for hitting.

The shaft of the wood passes through a hole in the top of the head and is directly connected to the base of the head. The shaft is either welded or cast or welded and cast both to the top and bottom of the head.

In this arrangement, no hossel or sleeve for the shaft is required, rather the shaft is joined directly to the head, thereby providing a stronger arrangement which is less prone to breakage.

In all the irons and woods shown in Figures 1 to 15 the majority of the shaft lies on the axis passing near the centre of gravity, preferably 65% of the shaft lies on the axis, more preferably 80%, most preferably 90%, and best of all 100%.

In all the irons and woods shown in Figures 1 to 15 the majority of the grip lies on the axis passing near the centre of gravity, preferably 75% of the shaft lies on the axis, and most preferably 100%.

The advantages achieved by the irons and woods in accordance with the invention are as follows :-

1. It is easier to deliver the face of the iron or wood square to the intended line of direction for the ball.

2. There is more resistance to twist during swing of the golf club.

3. There is more resistance to twist during striking of the ball.

4. One achieves a more solid hit of the ball.

Basically, one achieves these results due to the "balanced" nature of the head on the outer end of the shaft of the golf club.

Since the club provides a more solid hit, such means that one can hit the ball further, which is important for a No. l driver.

Claims

1. An iron or wood type golf club comprises a head with a sweet spot and a centre of mass, a grip, and a shaft, wherein at least a majority of the shaft lies on an axis which passes within 1 inch of either the centre of the sweet spot or the centre of mass of the head.

2. An iron or wood type golf club comprises a head, a grip, and a shaft, the head having a top, a front face, a rear, an inner side and an outer side, the front face providing a striking face for a ball, wherein at least a majority of the shaft lies on an axis which passes at least 0.65 inches from the inner side's outermost extremity.

3. An iron or wood type golf club having a head, a grip and a shaft, the head being at least 35 % weight balanced about an axis passing through a majority of the grip and/or shaft.

4. An iron or wood type golf club having a head, a grip and a shaft, the head having an unbalanced weight of less than 7.5oz about an axis passing through a majority of the grip and/or shaft.

5. A golf club as claimed in any preceding claim wherein the head has a top, a front face, a rear, or inner side and an outer side, the front face providing a striking face for a ball, and the shaft axis passes at least 0.75 inches from the inner side's outermost extremity.

6. A golf club as claimed in any preceding claim wherein the head is provided with a sweet spot and a centre of mass, and wherein the grip and at least a majority of the shaft lie on an axis which passes within 1 inch of either the centre of the sweet spot or the centre of mass of the head.

7. A golf club as claimed in any preceding claim wherein the grip has an axis and the shaft has an axis.

8. A golf club as claimed in any preceding claim wherein the shaft axis and/or grip axis comprises the axis which passes within 1 inch of either the centre of the sweet spot or the centre or mass of the head.

9. A golf club as claimed in any preceding claim wherein the shaft axis and/or grip axis comprises the axis which passes at least 0.65 inches from the inner side's outermost extremity.

10. A golf club as claimed in any preceding claim wherein the whole of the shaft and the grip lies on the same axis.

11. A golf club as claimed in any preceding claim wherein a hossel is provided on th e head, the hossel being bent relative to the grip and/or shaft axis.

12. A golf club as claimed in any preceding claim wherein the axis of the grip and/or the axis of the shaft passes within 0.75 inches of the centre of the sweet spot or the centre of the mass of the head.

13. A golf club as claimed in any preceding claim wherein the axis of the grip and/or the axis of the shaft intersects the striking face more than 0.75 inch from the inner side's outermost extremity.

14. A golf club as claimed in any preceding claim wherein the head has a centreline, and wherein the axis of the grip and/or the axis of the shaft intersects the striking face less than 1 inch from the centreline of the head.

15. A golf club as claimed in any preceding claim wherein the axis of the grip and/or the axis of the shaft intersects the striking face in the sweet spot.

16. A golf club as claimed in any preceding claim wherein the head has a sole and a centreline, and wherein the axis of the grip and/or the axis of the shaft intersects to sole a distance of less than 0.75 inches toward the toe from the centreline of the head.

17. A golf club as claimed in any preceding claim wherein the head has a sole and a centreline, and wherein the axis of the grip and/or the axis of the shaft intersects the centreline of the head less than 1 inch from the sole.

18. A golf club as claimed in any preceding claim wherein the head has a front face, the front face providing a striking face for a ball.

19. A golf club as claimed in claim 18 wherein the striking face has a loft of at least 7°.

20. A golf club as claimed in either claim 18 or 19 wherein the striking face has a substantially uniform shape.

21. A golf club as claimed in any one of claims 18 to 20 wherein the striking face has a substantially oval shape.

22. A golf club as claimed in any preceding claim wherein the head has a cavity back.

23. A golf club as claimed in any preceding claim wherein the head is peripherally weighted.

24. A golf club as claimed in any preceding claim wherein the head has a lower surface and a top surface, and wherein the lower surface of the head is wider and more weighted than the top surface of the head.

25. A golf club as claimed in any preceding claim wherein a front insert is provided.

26. A golf club as claimed in any preceding claim wherein a rear insert is provided.

27. A golf club as claimed in any preceding claim wherein the head has a sole, and wherein the sole has a multi-lie arrangement.

28. A golf club as claimed in any preceding claim wherein at least part of the axis of the shaft is offset from the axis of the grip.

29. A golf club as claimed in any preceding claim wherein the shaft is connected to the head via a straight hossel.

30. A golf club as claimed in any preceding claim wherein the head has a top, and wherein the shaft is attached directly to the top of the head.

31. A golf club as claimed in any preceding claim wherein the club is face balanced.

32. A golf club as claimed in any preceding claim which is a wood type club wherein the head is made of metal.

33. A golf club as claimed in any preceding claim which is a wood type club wherein the head is substantially hollow.

34. A golf club as claimed in any preceding claim wherein the striking face is substantially flat.