WO2005023373A2

WO2005023373A2 - Vented golf club shaft

Info

Publication number: WO2005023373A2
Application number: PCT/US2004/026371
Authority: WO
Inventors: Bruce D. Burrows
Original assignee: Burrows Golf, Llc
Priority date: 2003-08-28
Filing date: 2004-08-13
Publication date: 2005-03-17
Also published as: US20040048683A1; WO2005023373A3

Abstract

A golf club (10) including an elongated hollow club shaft (12) connected at one end to a golf club head (14), and having a grip (16) mounted at an opposite end thereof. The club shaft is vented to permit and facilitate transmission of shock energy generated upon normal striking impact with a golf ball from the golf club in the form of acoustic energy, while substantially reducing or eliminating transmission of the shock energy in the form of vibration to the golfer’s hands. In a first embodiment, a plurality of vents (24) are formed in the club shaft at a location near the grip. In a second embodiment, a plurality of vents (124) are formed in a cap (26) mounted onto the club shaft at the grip end thereof.

Description

VENTED GOLF CLUB SHAFT

BACKGROUND OF THE INVENTION

This invention relates generally to improvements in golf clubs. More particularly, this invention relates to an improved golf club having a hollow shaft that is vented for permitting and facilitating transmission of shock energy generated upon normal striking impact with a golf ball from the golf club in the form of acoustic energy, to correspondingly and substantially reduce or eliminate transmission of the shock energy in the form of vibration to the golfer's hands. Golf clubs are well known in the art, to include a club head such as a wood-type or iron-type club head mounted at a lower end of an elongated club shaft. An upper end of the club shaft has a resilient grip mounted thereon and designed for comfortable manual grasping and swinging of the golf club to strike a golf ball. In modern golf clubs, the wood-type or iron-type club head is commonly formed from a cast or machined metal or metal alloy such as stainless steel, titanium alloy, and the like. The club shaft is commonly formed from a selected metal or metal alloy, or alternately from a nonmetallic composite material such as a graphite-based composite. The club shaft typically has an elongated tubular or hollow construction with a stiffness or flexibility (whip) characteristic that may be variably selected in accordance with the preferences of an individual golfer. The grip mounted onto the club shaft at the upper end thereof is normally formed from a selected resilient elastomer. During normal club use, substantial shock energy is generated when a golfer swings the club to strike a golf ball. This shock energy primarily takes the form of vibrations transmitted through the club shaft from the club head to the grip for tactile detection by the golfer's hands. In this regard, this vibrational energy is particularly susceptible to such feedback tactile detection when the point of golf ball impact with the club head is off- center, i.e., misaligned with an optimal ball striking zone commonly referred to as the "sweet spot". For many amateur golfers, off-center ball impacts occur relatively frequently, resulting in a correspondingly frequent negative tactile feedback indicative of improper ball-head alignment and typically further indicative of a poor golf shot. Such negative tactile feedback can be discouraging, and thereby undermines enjoyment of the game. The present invention relates to an improved golf club having a vented club shaft, so that a substantial portion of the shock wave or shock energy generated upon ball impact can be transmitted or discharged from the club in the form of acoustic energy or sound, thereby significantly reducing or eliminating the transmission of the shock energy in the form of vibration to the golfer's hands.

SUMMARY OF THE INVENTION

In accordance with the invention, a golf club is provided with a vented shaft to permit and facilitate transmission and discharge of shock energy, generated upon normal striking impact with a golf ball, from the golf club in the form of acoustic energy or sound, thereby substantially reducing or eliminating transmission of shock energy in the form of vibration to the golfer's hands. The improved golf club comprises an elongated hollow club shaft connected at one end to a golf club head, and having a grip mounted generally at an opposite end thereof. In one preferred form, the club shaft includes at least one and preferably a plurality of vent ports formed therein at a location near the grip. In an alternative preferred form, at least one and preferably a plurality of vent ports are formed in an end cap mounted onto the club shaft at the grip end thereof. In either embodiment, upon striking impact of the club head with a golf ball, a substantial portion of the resultant shock energy transmitted from the club head to the club shaft is discharged through the vent ports to the surrounding air in the form of acoustic energy or sound, which is both readily audible and distinctive. Conversely, any residual portion of this shock energy available for transmission to the golfer's hands in the form of vibration is significantly reduced. Other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate the invention. In such drawings: FIGURE 1 is a perspective view of a golf club incorporating a vented shaft in accordance with the present invention; FIGURE 2 is an enlarged fragmented perspective view corresponding generally with the encircled region 2-2 of FIG. 1 ; FIGURE 3 is an enlarged transverse sectional view taken generally on the line 3-3 of FIG. 2; FIGURE 4 is an enlarged fragmented perspective view similar to FIG. 2, but depicting a modified embodiment of the invention; FIGURE 5 is an enlarged and fragmented sectional view illustrating one alternative preferred form of the invention; FIGURE 6 is a top end view of a golf club shaft, taken generally on the line 6-6 of FIG. 5; and FIGURE 7 is a fragmented exploded perspective view illustrating assembly of the components illustrated in the embodiment of FIGS.4 and 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in the exemplary drawings, an improved golf club referred to generally by the reference numeral 10 is provided with an elongated vented hollow club shaft 12. The club shaft 12 is connected at a lower end to a club head 14 (FIGURE 1 ), and carries a resilient grip 16 mounted at an upper end thereof. In use, upon swinging of the golf club to strike the club head 14 against a golf ball (not shown), the vented shaft 12 permits and facilitates transmission of resultant ball impact shock energy from the club in the form of acoustic energy or sound, while significantly reducing or eliminating transmission of the shock energy in the form of vibration to the golfer's hands. The illustrative golf club 10 shown in FIGURE 1 has an overall, generally conventional construction to include the elongated club shaft 12 connected to the club head 14 and having the resilient grip 16 mounted thereon. In this regard, FIG. 1 shows the club head 14 in the form of a wood- type club head having a front ball impact face 18 for striking a golf ball. In accordance with modern golf club construction, the wood-type head 14 may comprise a so-called metal wood club head comprising a hollow head construction formed from a selected cast or machined metal or alloy such as stainless steel, titanium alloy, etc. As shown, the club head 14 has a hosel 20 formed generally at a heel end thereof for connection in any suitable and known manner to the lower end of the club shaft 12. While the invention is shown and described herein with respect to a golf club 10 having a wood-type club head 14 as shown in the illustrative drawings, persons skilled in the art will recognize and appreciate that the club head may alternatively comprise any one of a standard set of iron-type golf clubs, a putter, or a sand or pitching wedge or the like. The club shaft 12 has an elongated hollow tubular construction extending from the connection thereof to the club head 14 to an upper end having the resilient grip 16 mounted thereon. The club shaft 12 may be formed from a suitable metal shaft material, such as stainless steel or the like, or alternatively formed from a nonmetallic material such as a graphite- based composite or the like. The specific stiffness or flexibility (whip) characteristics of the club shaft 12 may be expressly selected or tailored to suit the custom preferences of an individual golfer. The resilient grip 16 is shown in the form of a molded elastomer sleeve having a size and shape for slide-fit mounting onto the upper end of the golf club shaft 12. The grip 16 preferably incorporates an external surface grid pattern or texture 22 (shown best in FIG.2) for facilitated manual grasping and secure gripping by the player's hands. Alternative grip configurations are known, such as an elongated strip of elastomer or leather material for spiral wrapping about the upper end portion of the club shaft 12. In use, as is well known and understood, the golfer grasps the grip 16 while manually swinging the club shaft 12 to drive the front impact face 18 of the club head 14 into impact engagement with a golf ball. As the club head 12 contacts the golf ball with a substantial shock impact, the ball is driven forwardly in the direction of club head movement. At the same time, substantial reaction forces are transmitted to the club head in the form of a shock wave or shock energy for dissipation by transmission along the club shaft 12 and further to the golfer's hands, typically in the form of vibrational energy. The magnitude of this vibrational energy can be significant, and is noticeable by tactile detection with the golfer's hands, particularly when the ball impact point on the club head face 18 is outside an optimal ball impact zone or sweet spot. In accordance with the present invention, the hollow club shaft 12 is vented so that a substantial portion of this shock wave or shock energy can be transmitted and discharged from the golf club in the form of acoustic energy or sound, rather than transmitted in the form of vibration to the golfer's hands. In this regard, in one preferred form of the invention, the club shaft 12 as shown in FIGS. 1-3 includes a plurality of small vent ports 24 formed therein at a location near but preferably a short distance below the lowermost end of the resilient grip 16. FIG. 3 shows a plurality of eight small vent ports 24 formed at equiangular intervals about the club shaft circumference, with each vent port having a narrow width of about 1/8 inch and a length of about ^ΛA inch, and with the array of vent ports 24 disposed about 1/4 - ! inch below the lowermost end of the grip 16. FIG. 4 illustrates a modified embodiment of the improved golf club 10 as shown and described in FIGS. 1-3. In particular, FIG. 4 shows a reinforcement ring or sleeve 25 mounted about the club shaft 12, wherein this sleeve 25 has a plurality of vent ports 24' formed therein in alignment with the vent ports 24 formed in the club shaft 12 as previously described and shown in FIGS. 1-3. The vented reinforcement sleeve 25 may be formed from metal or other suitably stiff material for secure mounting onto the club shaft 12 in alignment with the vent ports 24. This reinforcement sleeve 25 is normally used with a nonmetallic club shaft 12, such as a graphite composite shaft, to strengthen the shaft in the region of the vent ports 24. With this construction, it has been found that a significant portion of the ball impact shock energy transmitted from the club head 14 to the shaft 12 is emanated or discharged from the club shaft in the form of a readily audible and distinctive acoustic wave or sound. Such dissipation of a substantial portion of this ball impact shock energy significantly reduces the residual energy available for transmission in the form of vibration to the golfer's hands. As a result, the golfer is able to detect by tactile sensation little if any of this residual energy. Instead, each golf shot is accompanied by a more solid tactile sensation together with a distinctive audible ring or click emanating from the vent ports 24, whereby the confidence level of the golfer is maintained despite an occasion misaligned or mishit golf shot. FIGS. 5-7 illustrate another alternative preferred form of the invention, wherein alternative vent ports 124 are formed in an end cap 26 having a size and shape for mounting onto the upper end of the club shaft 12. More particularly, the cap 124 may be constructed from metal or molded plastic or the like, and includes the multiple vent ports 124 for communicating the interior of the club shaft 12 with the surrounding air. FIGS. 5-7 show the cap 26 to have a raised central body 28 having the vent ports 124 formed therein, in combination with a recessed peripheral flange 30 projecting radially outwardly therefrom. This flange 30 has a size and shape to overlie the upper end of the club shaft 12, and is securely retained thereon by a radially in-turned lip 32 formed at the upper end of the resilient grip 16. The lip 32 defines a central aperture 34 for seated reception and retention of the cap body 28. In use, the vent ports 124 formed in the end cap 26 function in the same manner as previously described with respect to the vent ports 24 shown in FIGS. 1-3. A substantial portion of the ball impact shock energy is transmitted through the vent ports 124 in the form of acoustic energy or sound, thereby significantly reducing the residual shock energy available for transmission in the form of vibration to the golfer's hands. The embodiment of FIGS. 5-7 is particularly suitable for retrofitting the invention to existing golf clubs. A variety of further modifications and improvements in and to the improved golf club head of the present invention will be apparent to those persons skilled in the art. Accordingly, no limitation on the invention is intended by way of the foregoing description and accompanying drawings, except as set forth in the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A golf club, comprising: a club head; a club shaft having a hollow tubular construction and a lower end connected to said club head; and a grip mounted on said club shaft generally at an upper end thereof; said club shaft being vented to permit discharge from said club shaft of a portion of shock energy generated upon impact of said club head with a golf ball, thereby reducing the magnitude of shock energy transmitted to a golfer's hands grasping said grip.

2. The golf club of claim 1 wherein said club head comprises a metal wood club head.

3. The golf club of claim 1 wherein said club head comprises an iron type club head.

4. The golf club of claim 1 wherein said club shaft comprises a metal shaft.

5. The golf club of claim 1 wherein said club shaft comprises a composite material.

6. The golf club of claim 1 wherein said grip comprises a resilient material.

7. The golf club of claim 1 wherein said vented club shaft includes at least one vent port formed therein at a position disposed generally in closely spaced relation to said grip.

8. The golf club of claim 1 wherein said vented club shaft includes a circumferentially spaced array of vent ports formed therein at a position generally in closely spaced relation to said grip.

9. The golf club of claim 8 further including a reinforcement sleeve mounted on said club shaft generally in surrounding relation to said vent ports, said reinforcement sleeve having a circumferentially spaced array of openings formed therein generally in respective alignment with said vent ports formed in said club shaft.

10. The golf club of claim 8 wherein said array of vent ports are formed in said club shaft on the order of about 1/4 to about ¹/₂ inch from a lowermost end of said grip.

11. The golf club of claim 10 wherein each of said vent ports has a width of about 1/8 inch, and a length of about V2 inch.

12. The golf club of claim 8 wherein each of said vent ports has a width of about 1/8 inch, and a length of about ^ΛA inch.

13. The golf club of claim 1 further including a vented cap mounted on an upper end of said vented club shaft, said vented cap having at least one vent port formed therein.

14. The golf club of claim 13 wherein said grip includes a radially in-turned lip at an upper end thereof for engaging and retaining said vented cap on said shaft upper end.

15. The golf club of claim 1 further including a vented cap mounted on an upper end of said vented club shaft, said vented cap having a plurality of vent ports formed therein.

16. A golf club, comprising: a club head; a club shaft having a hollow tubular construction and a lower end connected to said club head; and a grip mounted on said club shaft generally at an upper end thereof; said club shaft having a circumferentially spaced array of vent ports formed therein at a position generally in closely spaced relation to said grip, said vent ports permitting discharge from said club shaft of a portion of shock energy generated upon impact of said club head with a golf ball, thereby reducing the magnitude of shock energy transmitted to a golfer's hands grasping said grip.

17. The golf club of claim 16 further including a reinforcement sleeve mounted on said club shaft generally in surrounding relation to said vent ports, said reinforcement sleeve having a circumferentially spaced array of openings formed therein generally in respective alignment with said vent ports formed in said club shaft.

18. A golf club, comprising: a club head; a club shaft having a hollow tubular construction and a lower end connected to said club head; a grip mounted on said club shaft generally at an upper end thereof; and a vented cap mounted on an upper end of said vented club shaft, said vented cap having at least one vent port formed therein for permitting discharge from said club shaft of a portion of shock energy generated upon impact of said club head with a golf ball, thereby reducing the magnitude of shock energy transmitted to a golfer's hands grasping said grip.

19. The golf club of claim 18 wherein said grip includes a radially in-turned lip at an upper end thereof for engaging and retaining said vented cap on said shaft upper end.