Weighted grip

Abstract

 The invention provides a golf club, a putter, wherein a shaft is fixed within a large diameter grip by means of inserts which are in the form of weighting elements. In one embodiment the weighting element is in the form of an end cap at the end of the grip thereby forming a balancing moment to counter the force acting at impact. In another embodiment weighting elements are provided at both ends of the grip to provide a "high-inertia"grip.

Description

[0001] This invention relates to golf clubs. More particularly the invention relates to a weighted grip for putters. In the article "Bubbling Over", Golf World, March 1995 an account of the development of the Taylor Made's Bubble shaft is given. In this article the point is made that it is good for golf clubheads to have a high moment of inertia but low inertia is good for clubs as a whole. It is particularly worth noting that this article stresses that the upper part of the club at the grip end is designed to keep the upper part of the club as light as possible - some 40% lighter than standard. Whilst this design philosophy may be true with respect to golf clubs such as drivers and irons where a low overall inertia will contribute to a faster swing speed, in putting, a slower more controlled stroke, preferably a linear stroke, is required. Accordingly a putter with a weighted or high inertia grip is more likely to contribute to a slower more controlled putting stroke. Moreover modern theories of putting emphasise the use of substantially large or over-size grips. US patent 4746120 (Mockvak) discloses a putter having a grip diameter of at least 2.5 inches (63.5mm) and discusses how this promotes balance and stability of the muscles used in putting. US patent 4272077 (Spivey) discloses a putter having a grip between 1.25 and 1.87 inches (31.8 and 47.7mm) and discusses how putter grips of these dimensions relax the hands and prevents jerking of unbalanced muscles. US patent 5569098 (Klein) contains an excellent discussion of the mechanics of putting and how this is facilitated by over-size grips. Amongst other things this patent teaches that the large diameter grip greatly reduces excessive wrist action and promotes the use of a looser grip which improves kinesthetic feedback thus enhancing the tactile sensitivity of the golfer's hands. Accordingly the reaction forces acting on the club when the ball is struck can be better felt. In the book "The Search for the Perfect Swing", published 1968, page 135, it is postulated that an optimum putter design can be achieved by redistributing the weight to the sides of the putter head. This design philosophy is confirmed in US patent 3941390 (Hussey) which teaches that to achieve a maximised moment of inertia weighting material should be placed as far as possible from the neutral axis under consideration.

[0002] An object of the present invention is to further develop the above principles in the design of putters.

[0003] In pursuit of the above objective it is postulated that in addition to the provision of putters having large or over-size grips the putting stroke can be made easier by the provision of hard surface grips. Hard surface grips are believed to encourage tension free putting. The phenomenon is best explained with reference to the use of a soft rubber exercise ball. The "give" of the soft rubber squeeze ball which is analagous to traditional rubber or synthetic golf club grips encourages repetitive squeezing of the ball which sets up tension in the fingers which in turn can spread to the larger body members such as the wrists and arms and leads to a jerky putting stroke. On the other hand with a hard gripping surface there is no kinesthetic feed-back so that the brain switches off and there is no tendency for repetitive squeezing of the grip. Thus the fingers tend to remain relaxed and tension free. US patent 5575473 (Terry S Turner - 1996) discloses a weighted grip for a putter. Weighting elements in the form of steel or other metal collars are disposed solely within the length of the grip. The weighting or inertia effect of the steel collars is thus limited.

[0004] According to the present invention there is provided a golf club comprising a head, a grip and a shaft connecting the head and the grip wherein the grip comprises an elongate, thin-walled, tubular, hollow grip member having a cross-sectional dimension substantially greater than the shaft and providing a relatively hard outer gripping surface, first and second support members spacing the grip member from the shaft whereby a void is formed between the grip member and the shaft wherein one of the support members forms a weighting element in the form of an end cap for the grip .

[0005] The invention will now be described by way of example only with reference to the undernoted drawings wherein:

Figure 1 is a view generally of a putter having a grip in accordance with the present invention.

Figure 2 is a part sectional elevation showing in more detail one aspect of the grip of the present invention.

Figure 3 is a part sectional elevation of a grip in accordance with a second aspect of the present invention.

Figure 4 is a perspective view of a split bush in accordance with a further aspect of the invention.

[0006] In figure 1 there is shown a putter 10 in accordance with the present invention. Putter 10 comprises a putter head 11, grip 12 and a shaft 13 connecting the head and the grip. Shaft 13 is a tubular hollow tapered shaft and may be of any configuration and material and may be connected to the head by means of a hosel 14. Hosel 14 may be hollow. Grip 12 according to one aspect of the invention is shown in greater detail in figure 2. Grip 12 comprises a parallel sided, thin-walled, circular, tubular, hollow grip member 15 having a head end 16 and a shaft end 17. From figure 2 it is clear that grip member 15 has a cross-sectional dimension, that is, a diameter substantially greater than shaft 13. Grip member 15 is not covered in any conventional grip material such as rubber or leather or synthetic composites thereof since it is believed that such coverings tend to absorb impact sensations thereby detracting from the "feel" of the putter. Grip member 15 is supported at the head end 16 by a first support member 18 and at the shaft end 17 by means of a second support member 19. Support member 19 has an internal through bore 20 which has a relief portion 21 which acts as a reservoir for adhesive material. Support member 19 also has a tapered nose portion 22 which provides for a more gradual transition between the substantially large cross-sectional dimension grip member 15 and the shaft 13. In addition to forming a support for shaft member 13 the support members 18, 19 act as spacers, spacing the grip member 15 from the shaft 13 thereby providing a void 23 between the shaft 13 and the grip member 15. Forming a void in this manner and extending the shaft 13 through the grip member 15 enhances the "feel" of the putter. It is believed that sensations of impact when a ball is struck are thereby conveyed more efficiently to the grip 12 resulting in greater "feel". In addition to acting as spacers the support members 18, 19 act as sealing members preventing dirt and moisture from entering the void 23. Grip member 15, shaft 13 and support members 18, 19 defining the void 23 are assembled together using a suitable adhesive, for example, a one or two part epoxy adhesive. Double sided adhesive tape may also be used. In accordance with one aspect of the invention support member 18 is made to form a weighting element in the form of an end cap 24 curved to suit the hand of a user whereas support member 19 is made of a suitable light weight material. Thus weighting element 24 forms a back weight. The back weight times the distance to the neutral axis N-N of the grip 12 forms a moment which tends to balance the moment created at impact and thereby contributes to the linear stroke which is thought to be highly desirable in putting. Because the weighting element in the form of the end cap 24 protruding outwardly of grip member 15 the balancing moment effect is maximised.
In figure 3 there is shown a further aspect of the present invention. In figure 3 like numerals refer to like items as previously descibed for figure 2 so that there is shown a grip member 15, first and second support members 18, 19 defining a void 23 with shaft 13. Support member 18 forms a weighting element 24 as previously describd and support member 19 with tapered nose portion 22, in this embodiment is in the form of a further weighting element 25, Weighting element 25 protrudes outwardly of grip member 15 thereby increasing the inertia effect. Weighting elements 24, 25 being displaced a maximised distance from the neutral or gripping axis N-N produces a high inertia grip. An ideal material for weighting elements 24, 25 is the material disclosed in British patent Publication No 2277321. This material comprises particles of heavy metals such as, lead and tungsten in a matrix of mouldable or extrudable material. Thus in addition to providing a weighting function this material provides some vibration damping or shock absortion. In figure 4 there is shown a further aspect of the present invention. In figure 4 the numeral 25 represents a support member 25 in the form of a split bush member 26. Split bush member 26 has a conical nose portion 27 so that it may form a transition piece bet ween shaft 13 and over-size grip member 15. Split bush member 26 has a screw connection 28 and screw 29 for tightening split bush 26 around shaft 13. Thus once the conventional grip has been removed from an existing golf club support member 25 in the form of a light weight support member or a heavier weighting element may be retro-fitted to an existing golf club. In a practical embodiment of the present invention the grip member 15 had a length of 280mm (approx 11 inches). The grip can be longer, for example, to cater for spreading the fingers in the so called ten finger or baseball grip. Indeed, bearing in mind the Rules of Golf allow for a mimimum club length of 18 inches (457.2mm) the extended grip length could terminate only a very short distance from the hosel. The diameter of the grip member can range between 25 and 45mm with a preferred diameter being 31mm (approx 1,25 inches). The wall thickness of grip member 15 is between 0.75 and 1.00mm. Various hard materials can be used to provide a grip member with a hard outer gripping surface, for example, polypropylene, high density polyurethane, glass reinforced plastics material, light weight metals and alloys, however a preferred material is carbon fibre. A carbon fibre tube used to form grip member 15 has its outer tubular surface covered with a thin coating 30. The thickness of the coating 30 is of the order of ordinary paint being several microns thick, between say, 5 to 50 microns (1 micron = 1 thousandth of a mm). In practice the coating 30 is a non-slip soft touch paint which is sprayed on and oven baked. This provides a non-slip, non-shock absorbing surface for the grip member.

Claims

1. A golf club comprising a head, a grip and a shaft connectng the head and the grip wherein the grip comprises an elongate, thin-walled, tubular, hollow grip member having a cross-sectional dimension substantially greater than the shaft and providing a relatively hard outer gripping surface, first and second support members spacing the grip member from the shaft whereby a void is formed between the grip member and the shaft and wherein one of the support members forms a weighting element in the form of an end cap for the grip.

2. A golf club according to claim 1 wherein the other support member is made of light weight material.

3. A golf club according to claim 1 wherein the weighting element in the form of an end cap is curved to fit the hand of a user.

4. A golf club according to claim 1 wherein the weighting element in the form of an end cap protrudes outwardly of the grip member.

5. A golf club according to claim 1 wherein the support members form seals preventing the entry of dirt and moisture into the void.

6. A golf club according to claim 1 wherein the other support member is in the form of a weighting element.

7. A golf club according to claim 6 wherein the other support member in the form of a weighting element protrudes outwardly of the grip member.

8. A golf club according to claim 4 and claim 7 wherein the support members are each positioned a maximised distance from the neutral gripping axis of the grip to form a high inertia grip.

9. A golf club according to claim 1 wherein the other support member is in the form of a tapered transition piece between the substantially large grip member and the shaft.

10. A golf club according to claim 1 wherein one of the support members can be retro-fitted to an existing golf club.

11. A golf club according to claim 10 wherein the support member is in the form of a split bush with means to tighten the bush around an existing shaft.

12. A golf club according to claim 11 wherein the bush is tapered to provide a transition piece between the substantially large grip member and the shaft.

13. A golf club according to claim 1 comprising a putter.

Drawing