GB2374539A

GB2374539A - A golf club

Info

Publication number: GB2374539A
Application number: GB0107013A
Authority: GB
Inventors: James Stephen Boyd Mather; Dennis Vardy
Original assignee: IRONZ PLC
Current assignee: IRONZ PLC
Priority date: 2001-03-21
Filing date: 2001-03-21
Publication date: 2002-10-23
Also published as: GB0107013D0

Abstract

A golf club has a connector 4 between the shaft and club head. The connector has a hosel 6 for connection to the shaft and a head attachment member 7 for connection to the head. One or more bosses 15 extend from the rear of a striking plate 5 of the head and fixedly support the head attachment member in a position such that that there is a clearance defined between the head attachment member and the rear face of the striking plate. The clearance allows the striking member of the head to deflect rearwardly upon impact with the ball. The characteristics and size of the striking member are chosen so that after the initial impact it springs back to an equilibrium position before the ball leaves the striking face thereby imparting additional energy to the ball. An intermediate portion of the connector extends in a direction that is substantially perpendicular to line in the plane of the striking face.

Description

A GOLF CLUB The present invention relates to a golf club and more particularly to the structure of the head of a golf club and its connection to the shaft of the club.

A conventional golf club comprises an elongate flexible shaft at an upper end of which is a handle by which the club is gripped and a club head that is connected to a lower end of the shaft.

An iron-type club has an asymmetric club head in the form of a plate with heel and toe ends. A front ball-striking face of the head is inclined to the vertical by an angle known as the loft angle. The magnitude of the loft angle dictates the shot capability that is offered by the club. At the heel end of the head there is an integral hosel in the form of a cylindrical socket that extends upwardly and is designed to receive the lower end of the shaft. The head is tapered inwardly from toe to heel such that when a bottom edge of the head is approximately parallel to the ground a top edge of the club head is inclined downwardly from the toe end to the heel end where it is connected to the shaft.

The asymmetric head shape of an iron-type club makes it difficult to hit the golf ball with the"sweet spot" (the centre of percussion) of the striking face of the club head. Moreover, when playing the ball in long grass the taper encourages blades of grass to travel down the top edge of the head to hosel where they wrap around the area of intersection between the hosel and the rest of the club head.

A wood-type club has a head that is approximately oval in shape with a flat front striking face and a rear internal hollow. The head again has an integral cylindrical hosel that extends upwardly and receives the lower end of the shaft.

Each club head has to be moulded, cast or forged to a particular design and if it is desired to vary the loft or lie angles to account for different golfers it is necessary to repeat the manufacturing process or to strike the club head or hosel with a large weight.

Many golf clubs are designed with a view to increasing the area of the sweet spot so that the ball travels further and straighter. Alternatively the clubs are designed to be less sensitive to mis-hit shots where the ball is hit at a point offset from the

sweet spot or there is relative lateral movement between the ball and the striking face during impact. In order to reduce the tendency for the ball to be hooked or sliced as a result of mis-hits the resistance to twisting of the club head during swinging and impact is increased as far as is possible. This is usually achieved by adding weight to the periphery of the club head.

US 5447307 (Antonius) describes an iron golf club in which the hosel has a lower section that is integrally connected to the back of the club head and in some embodiments extends across and overlies the back face of the club head from heel to toe. The arrangement improves the connection between the club head and the hosel and attempts to ensure that maximum kinetic energy from a swinging club is transferred to the ball. Moreover, the hosel is disposed so as to be behind the front fact of the club head so as to reduce the tendency for it to hit the ball (known as a"shank shot").

US 6080068 (Takeda) describes both iron and wood type golf clubs in which the club head is attached to the shaft by a connector having a shaft attachment portion defining the hosel and an integral head attachment portion that extends across the rear face of the head from heel to toe and is securely fastened thereto. The head attachment portion is designed to reduce both the inertial moment of the head and the amount the head deflects upon impact with the ball. Several parameters of the design can be varied to determine the characteristics of the club in use thereby enabling the club to be customised during manufacture or assembly so as to meet the particular requirements of the player. For example, the provision of a separate connector between the shaft and head allows the loft and lie angles to be varied during manufacture. Moreover, the material for the shaft and head attachment portions can be selected to affect the weight distribution in the head whereas its location relative to the head affects the centre of gravity.

The clubs described in both the above patents overcome some but not all of the disadvantages referred to above. There is still a requirement for a golf club structure that permits design variations to be incorporated easily in the manufacturing process so that clubs can be used by a wide range of players of differing standards and can be

customised to the specific requirements of a particular player. The heads of clubs are traditionally designed from the point of view of ensuring maximum impact force at the time of striking the ball so as to improve the distance the ball travels and its accuracy. The thickness of the striking face is selected for strength and rigidity to ensure maximum transfer of energy. Moreover, the periphery of the head is generally is generally even thicker to improve the weight distribution and to provide resistance to twisting.

There has always been a desire for golf clubs that enable a player to hit a golf ball further. It will be understood that according to the conservation of momentum principle the product of the mass and velocity of the golf ball is equal to the product of the mass and velocity of the club head at the time of impact with the ball. The rules of golf impose fixed limits to the mass of the ball and increasing the mass of the club head is not desirable since it requires greater effort on the part of the player to overcome the weight and increased drag. It has thus been recognised that to increase the velocity of the golf ball, and therefore the distance it travels, it is necessary to increase the velocity of the club head. Many different designs have been proposed to varying degrees of success. However, many of those require complex manufacturing techniques and the clubs are therefore costly to produce.

It is an object of the present invention to obviate or mitigate the aforesaid disadvantages.

According to a first aspect of the present invention there is provided a golf club head assembly comprising: a club head with a striking member having heel and toe ends, a striking face and a rear face; and a connector for attaching the head to a shaft; a first portion of the connector having a shaft attachment member, a second portion of the connector having a head attachment member for connection to the head; at least one support member extending rearwardly from the striking member, the head attachment member being connected to the support member such that there is a clearance defined between the head attachment member and the rear face of the striking member.

such that there is a clearance defined between the head attachment member and the rear face of the striking member.

The clearance allows the striking member of the head to deflect rearwardly upon impact with the ball. The characteristics and size of the striking member are chosen so that after the initial impact it springs back to an equilibrium position before the ball leaves the striking face thereby imparting additional energy to the ball.

In a preferred embodiment the head attachment member extends across from heel to toe end of the striking member.

The striking member is preferably in the form of a plate that has a substantially planar striking face and the head attachment member extends substantially in parallel to the striking face.

The face is preferably symmetrical about at least one axis and may be substantially rectangular with two axes of symmetry.

Ideally, there are a pair of support members that are preferably spaced apart, one preferably at or near the toe end and the other at or near the heel end. Additional support members may be provided. Each support member is preferably in the form of a boss having an aperture in which the head attachment member is supported and to which it is fixed.

The support members may be of different sizes so as to provide a pre-selected mass balance across the club. In addition, or alternatively, the members may be constructed from different materials The support members may be vertically offset.

The head attachment member is preferably cylindrical.

The striking member has upper and lower edges that are ideally substantially parallel.

The shaft attachment member may be a hosel socket for receipt of a shaft.

The connector preferably has an intermediate portion between the head attachment member and the shaft attachment member. In a preferred embodiment the intermediate portion has a longitudinal axis that extends in a direction that is substantially perpendicular to an imaginary line on the plane of the striking face of the

club head. The intermediate portion may be cranked and may extend in a direction substantially perpendicular to the axis extending between the heel and toe ends. In addition its axis may be substantially perpendicular to the axis of the hosel. It may have a further section that extends coaxially with the hosel.

According to a second aspect of the present invention there is provided a golf club head assembly comprising: a club head with a striking member having heel and toe ends, a striking face and a rear face; and a connector for attaching the head to a shaft; a first portion of the connector having a shaft attachment member, a second portion of the connector having a head attachment member connected to the head; the connector having an intermediate portion between the first and second portions, the intermediate portion extending in a direction that is substantially perpendicular to line in the plane of the striking face.

Tests have established that this disposition of the intermediate portion provides for improved performance of a player in terms of shot distance and accuracy.

Specific embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a front view of an iron-type golf club head assembly according to the present invention; Figure 2 is a side view of the club head assembly of figure 1; Figure 3 is a plan view of the club head assembly of figure 1; Figure 4 is a perspective view from the rear of the club head assembly of figure 1; Figure 5 is a plan view of a wood-type golf club head assembly according to the present invention; Figure 6 shows the club head assembly of figure 5 with a top part removed to show the internal configuration; Figure 7 is a front view of the club head assembly of figure 5 with the front face removed to show the internal configuration; Figure 8 is a schematic plan view of an alternative embodiment of a club head striking member of the present invention;

Figure 9 is a schematic rear view of a further alternative embodiment of the striking member of the present invention; Figure 10 is a schematic rear view of a yet further alternative embodiment of the club head striking member of the present invention; Figure 11 is a schematic plan view of an alternative embodiment of the club head assembly of the present invention; Figure 12 is a schematic view from the side of a hosel and head attachment member of the club head assembly present invention; and Figure 13 is a schematic view from the side of an alternative embodiment of the hosel and head attachment member.

Referring now to the drawings, the iron type golf club head of figures 1 to 4 has a body 1 with a striking plate 2 by which a golf ball (not shown) is hit and a sole 3 which generally faces the ground in use. The head is attached to a golf club shaft (not shown) by means of a connector 4 that is described in detail below.

The body of the head is manufactured from any suitable material such as, for example, titanium, steel or a reinforced resin.

The striking plate 2 is integrally connected to the sole 3 at a pre-selected acute angle and has a leading planar striking face 5 by which the golf balls are hit. The face 5 is inclined to the vertical by an inclination known as the"loft"angle.

The connector 4 comprises an upstanding hosel 6 in the form of a cylindrical socket that is designed to receive the club shaft (not shown), and an integral mounting bar 7 for connection to the body 1 of the club head. The hosel 6 extends at an inclined angle to the vertical from what is known as the"heel"end 8 of the club head body 1.

The opposite end of the head remote from the hosel 6 is known as the"toe"end 9. In the exemplary embodiment of figures 1 to 4 the mounting bar 7 is double-cranked having two right-angled elbows 10,11. A first portion 12 of the mounting bar 7 extends coaxially with the hosel socket 6 and is joined at a first elbow 10 to an intermediate portion 13 that extends rearwardly and in a direction perpendicular to the hosel 6 and substantially parallel to the plane of the sole 3. An end portion 14 of the

mounting bar 7 extends at right angles from the intermediate portion 13 and is disposed behind the striking plate 2 where it is connected to the club head body 1.

The head connection (end) portion 14 of the bar 7 is received in two spaced bosses 15 that are integrally formed with the club head body 1 at the heel and toe ends 8,9 respectively. The bosses 15 are defined at the intersection between the rear of the striking plate 2 and the sole 3 and each has a circular aperture 16 in which the end portion 14 of the mounting bar 7 is fixedly received. The bosses 15 are arranged so as to support the end portion 14 of the bar 7 at a predetermined distance from the rear of the striking plate 2 and so that its longitudinal axis extends substantially in parallel to plane of the striking face 4. The bar 7 is fixed in place relative to the bosses 15 by any convenient means such as welding, brazing or gluing etc.

The connector 4 between the club head and shaft provides for flexibility in the manufacturing and assembly process. It enables many aspects of the club design to be varied or customised without having to manufacture an entire new head each time.

This is described in more detail below. The connector 4 and the club head body 1 engage at two discrete spaced locations only and the end portion 14 of the mounting bar 7 is held away from the rear of the striking plate 2 of the body 1 by the distance X.

These two features permit the striking plate 2 to deflect rearwardly upon initial impact with the ball. As the swing of the golf club progresses"through"the ball the club head and ball travel together for a short time after impact before the ball then leaves the head. The material of the striking plate of the club head is selected to have natural spring characteristics such that after the plate has deflected rearwardly upon initial impact it then springs back to its rest position thereby imparting additional energy to the golf ball to propel it forward. This increased transfer of energy from the club to the ball thereby allows the ball to travel further and straighter in comparison with prior club head designs.

The mass, material and thickness of the striking plate 2, the size of the clearance X and the mass, material and position of the bosses 15 can be carefully designed to provide the best results for a particular player. The connector 4 can be made in different sizes to suit different shafts that are available. It is therefore not

necessary to change the head to accommodate a new shaft; only the connector 4 requires replacement. The angle of the longitudinal axis of the hosel 6 to the vertical (which determines the lie angle) is selected to suit the player concerned.

The circular cross-section of the mounting bar 7 enables the body 1 of the club head to be rotated thereupon during assembly so as select the desirable loft angle.

The shape of the striking face 5 is approximately rectangular with rounded comers 17 and is symmetrical about the vertical axis Y shown in figure 1 of the drawings. The upper and lower edges 22,23 of the striking plate 2 extend substantially in parallel. This configuration of the striking plate 2 improves the ability of the player to strike a ball accurately from the rough. The blades of grass in the rough, instead of migrating from heel to toe of the club head, simply deflect over the upper edge 22 of the striking plate 2 and therefore do not impair the swing of the golf club.

An alternative embodiment of the present invention in the form of a wood-type golf club head will now be described with reference to figures 5 to 7 in which parts corresponding to those of figures 1 to 4 are indicated by the same reference numerals increased by 100 and are not further described except insofar as they differ from their counterparts in figures 1 to 4. The club head has a main body 101 with a striking plate 102 and a rear shell 120 that is semi-oval in configuration and extends rearwardly from the striking plate 102. The shell 120 defines a hollow cavity 121 behind the striking plate 102. The body 101 is connected to a shaft (not shown) by a connector 104 that, as before, comprises a hosel 106 that extends into an aperture 124 in a top surface 125 of the shell 120 and a mounting bar 107 for connection to rear of the striking plate 102. The bar 107 extends from the hosel 106 at the heel end 108 and across the rear of the striking plate 102 to the toe end 109 and is fixed to two spaced bosses 115 that project from the rear of the striking plate 102, as before. The design has the same advantages discussed above in relation to the iron-type club.

In both club designs the size, shape and position of the bosses 15,115 can be changed to alter the mass balance across the club head and thereby change the performance characteristics of the club. The mass balance of the club can also be

changed by selecting different materials for the manufacture of the bosses 115 and the head. For example, one of the bosses may be made from tungsten and the other from steel. A club head striking plate 202 with bosses 215a, 215b of different sizes (and therefore masses) is shown in figure 8.

The vertical position of the bosses relative to the striking plate can be varied during the manufacturing process. The position of the bosses determines the amount of spin that is imparted to the ball. For players that have difficulty in hitting the ball with a sufficiently steep trajectory the bosses are placed towards the top edge of the striking plate. The mounting bar 7,107 can be disposed so that its longitudinal axis is inclined to the upper edge 22,122 of the striking face 5,105. In order to achieve this the bosses 315a, 315b are vertically offset with the apertures 316 inclined to the horizontal as shown schematically in figure 9. If the mounting bar is disposed in this manner, the tendency for hooked and sliced shots that result from twisting movement of the striking plate relative to the ball during impact can be counteracted. The exact positions of the bosses would have to be selected empirically for any particular player. In an alternative design shown in figure 10 the bosses 415a, 415b are disposed so that they are inclined relative to the striking plate 402 to achieve the same effect.

In an alternative design depicted in figure 11, the end portion 514 of the mounting bar 507 of the connector 504 may extend only into the boss 515a at the heel end 508 of the body 501 of the club head. A planar bridge plate 530 is fixedly disposed to the rear of the bosses 515a, b in parallel to the striking plate 502 so as to provide a box structure that is mechanically stiff and robust.

Golf club shafts of different diameters may be used in connection with the same head. To accommodate this connectors 4,104 having different hosel socket 6, 106 diameters may be provided as part of a golf club collection.

The offset position of the longitudinal axis of the hosel (and therefore club shaft) with respect to the plane of the striking face 5,105 of the club head can be altered by having different connectors with intermediate portions 13,113 of the mounting bar 7,107 of different lengths (the length designated z in figure 12). In existing clubs this can only be altered by having a new club head moulded.

The angle of the intermediate portion 13,113 of the mounting bar 7,107 to the first portion 12,112 of the bar can be changed as required as indicated in figure 13. It has been established in tests that it is beneficial for the axis to be perpendicular to the face of the club.

It will be appreciated that numerous modifications to the above described design may be made without departing from the scope of the invention as defined in the appended claims. For example, the club head may be made from any suitable material such as metal (e. g. titanium or steel) or a reinforced resin and may be manufactured according to any suitable process e. g. moulding, forging or casting. Moreover, only one supporting boss may be provided and it is to be understood that the boss or bosses may be replaced by any form of support member that serves to support the mounting bar such that is clear of the rear face of the striking plate so as to allow the plate to deflect.

Claims

CLAIMS 1. A golf club head assembly comprising: a club head with a striking member having heel and toe ends, a striking face and a rear face; and a connector for attaching the head to a shaft; a first portion of the connector having a shaft attachment member, a second portion of the connector having a head attachment member for connection to the head; at least one support member extending rearwardly from the striking member, the head attachment member being connected to the support member such that there is a clearance defined between the head attachment member and the rear face of the striking member.
2. A golf club head assembly according to claim 1, wherein the head attachment member extends across the striking member from the heel to the toe ends.
3. A golf club head assembly according to claim 1 or 2, wherein the striking member is in the form of a plate.
4. A golf club head assembly according to claim 1,2 or 3, wherein the striking face of the member is substantially planar.
5. A golf club head assembly according to claim 4, wherein the head attachment member extends substantially in parallel to the striking face.
6. A golf club head assembly according to any one of claims 1 to 5, wherein the striking face is symmetrical about at least one axis.
7. A golf club head assembly according to any preceding claim, wherein the striking face is substantially rectangular with two axes of symmetry.

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8. A golf club head assembly according to any preceding claim, wherein there are a pair of support members that are laterally spaced.
9. A golf club head assembly according to claim 8, wherein one of the support members is disposed at or near the toe end and the other is disposed at or near the heel end of the club head.
10. A golf club head assembly according to any preceding claim wherein the (or each) support member is in the form of a boss having an aperture in which the head attachment member is supported.
11. A golf club head assembly according to claim 10, wherein the head attachment member is fixed to the boss.
12. A golf club head assembly according to claim 8 or 9, wherein the support members are of different sizes.
13. A golf club head assembly according to any one of claims 8,9 or 12, wherein the support members are constructed from different materials.
14. A golf club head assembly according to any one of claims 8,9 12 or 13, wherein the support members are vertically offset.
15. A golf club head assembly according to any preceding claim, wherein the head attachment member is cylindrical.
16. A golf club head assembly according to any preceding claim, wherein the striking member has upper and lower edges that are substantially in parallel.

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17. A golf club head assembly according to any preceding claim, wherein the shaft attachment member is a hosel socket for receipt of a shaft.
18. A golf club head assembly according to any preceding claim, wherein the connector has an intermediate portion between the head attachment member and the shaft attachment member.
19. A golf club head assembly according to claim 18, wherein the intermediate portion has a longitudinal axis that extends in a direction that is substantially perpendicular to an imaginary line on the plane of the striking face of the club head.
20. A golf club head assembly according to claim 18 or 19, wherein the intermediate portion extends in a direction substantially perpendicular to the axis extending between the heel and toe ends of the club head.
21. A golf club head assembly according to claim 20, wherein the intermediate portion extends in a direction substantially perpendicular to a longitudinal axis of the shaft attachment means.
22. A golf club head assembly according to claim 18, 19 or 20, wherein the intermediate portion is cranked.
23. A golf club head assembly according to any one of claims 18 to 22, wherein the intermediate portion has a section that extends coaxially with the hosel.
24. A golf club head assembly comprising: a club head with a striking member having heel and toe ends, a striking face and a rear face ; and a connector for attaching the head to a shaft; a first portion of the connector having a shaft attachment member, a second portion of the connector having a head

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attachment member connected to the head; the connector having an intermediate portion between the first and second portions, the intermediate portion extending in a direction that is substantially perpendicular to line in the plane of the striking face.
25. A golf club comprising a shaft and a golf club head assembly according to any preceding claim.
26. A golf club head assembly substantially as hereinbefore described with reference to the accompanying drawings.