WO2002070083A1

WO2002070083A1 - Golf swing practice device

Info

Publication number: WO2002070083A1
Application number: PCT/CA2002/000300
Authority: WO
Inventors: Christopher Robert Hudson
Original assignee: Christopher Robert Hudson
Priority date: 2001-03-02
Filing date: 2002-03-01
Publication date: 2002-09-12
Also published as: CA2339720A1

Abstract

A golf swing practice device is disclosed which comprises a light source which is preferably removably attached to the shaft of a golf club. The light source emits a line of light, or some other relational image of light, on the ground so as to provide an indication of the position of the club face of the golf club, at or near the top of the backswing. Using this device, the golfer or an observer can more readily determine the position of the golf club and face of the club at or near the top of the backswing. An improved golf teaching aid is thus provided.

Description

Golf swing practice device

FIELD OF THE INVENTION

This invention relates to a golf swing practice device which preferably can be removably attached to a conventional golf club and which enables a golfer who is practising a golf swing, to visually determine if the club face of the club head of a golf club is maintained in a "square" position in the backswing of the golfer, and/or in the initial stage of the downswing of the golfer.

BACKGROUND OF INVENTION

The use of light sources, light reflectors and light beams which are either built into a golf club or attached to a golf club, usually along the shaft of the club, are well known in the art and most commonly are employed for visually informing a golfer if the impact face of the club head is square to the target line at the point of actual or imagined golf ball impact.

One such attachment device is disclosed in US Pat. No. 5,467,991 issued Nov. 21, 1995, White, which discloses a base mounting plate which is removably attached to a club shaft and which supports a pair of light emitting diodes (LED's) aimed in opposite directions parallel to the shaft of the club.

As the beam of light emitted from the lowermost LED is offset relative to the axis of the club shaft, the light trace which the beam makes when it impinges the ground is behind the head of the club head. Because of this offset, the light trace on the ground is not representative of the actual location of the impact face of the club head, and further, does not produce a straight line ground light trace in the ball impact area due to the rotation of the hands and club in this area.

The second LED on the White device also emits a beam of light which is offset and parallel to the axis of the shaft, but which in this instance extends in a direction opposite to the first or lowermost beam. This second or upper beam, during the latter part of the back swing, the early part of the down swing and during follow through, is intended to produce a light trace on the ground which is parallel to the desired target line. While White's golf swing training device is useful in assisting a golfer in determining if the golfer's swing is following the correct swing plane by the two light tracings on the ground, it is not possible through the use of the single and offset downwardly projecting light beam to determine if the face of the club head at the point of actual or imaginary ball impact is on line to the ball, "square" to the ball or if it is open or closed to the ball and which is commonly described as a toe-in or toe-out condition. Toe-in or toe-out of the face of a club head normally imparts to an impacted ball unwanted side spin which results in either a hook or slice.

Cunningham in US Pat. No. 5,470,072 issued Nov. 28, 1995, provides for two spaced apart light sources positioned on the crown or top surface of a club head and which are also positioned in a plane perpendicular to the ball impact face of the club head. If the light tracings from the light sources (which are directed or reflected towards the golfer swinging the club and not the ground) appear superimposed at the point of actual or imaginary ball impact, it indicates to the person swinging the golf club that the face of the club head is square to the ball. However, if the two light tracings in the proximity of ball impact are offset one relative to the other, it is indicative that the club face is not square, and is either in a toe-in or toe-out condition.

Cunningham also discloses the attachment of a bar to a lower portion of the shaft of the club with the bar carrying light sources or light reflectors thereon, and which provides the golfer with the same interpretative information as given when the light sources are positioned on the crown of the golf head.

While Cunningham assists one in determining if the club face is square to the ball at the point of impact, no interpretative visual information is given the golfer about the golfer's swing being in the correct swing plane or if the imaginary ball which appears to be hit square, is in fact being hit square but in an "in-to-out" or an "out-to-in" swing arc relative to the desired target line; thereby creating what is termed a "push" or a "pull". Further, no information is provided to the golfer regarding the position of the club during the backswing or initial periods of the down swing.

In US Patent No. 5897441 (Apthorp), an improved device is described wherein two lasers are pointed down the club shaft towards the club head in a line which bisects the club face at right angles. During the down swing, the points of light "trace" two lines on the ground which should appear to cross one another at the point of impact, thus indicating to the golfer that the club face is square to the target at the point of impact.

Additionally, Apthorp describes a device having a third laser which emits a beam of light in a direction substantially coaxial with the axis of the club shaft, but in a direction away from the club head. During the later part of the backswing and the initial stages of the downswing, this third laser traces a line on the ground, and is representative of the true plane in which the shaft of the club is located. While determining that the club is on the correct swing plane is of some importance and utility, the third laser of Apthorp does not provide any indication on the position of the club face during the later stages of the backswing, or the initial stages of the downswing. Accordingly, at or near the top of the backswing, the device of Apthorp will indicate to the golfer whether the golf club is in the correct plane, but does not provide any indication to the golfer whether the club face is in an open, closed or square position. This can be of importance to the golfer since a open or closed club face in the initial portions of the downswing must be manipulated back to a square position prior to impact with the ball. Having the club in a square position during the later stages of the backswing and/or the initial stages of the downswing can minimize the amount of manipulation required to have the club face in a square position at the point of impact with the ball.

SUMMARY OF THE INVENTION

It is an object of the present invention, therefore, to provide a golf swing practice device which can provide feedback to the golfer to indicate whether the golf club is in an open, square, or closed position during the later stages of the backswing or the initial stages of the downswing. Accordingly, the present invention provides a golf swing practice device which can be preferably removably attached to the shaft or to the grip on the shaft of conventional golf club (either "woods" or "irons"), and which enables a golfer, through light tracings on the ground, to determine if the face of the club head is in a square position during the later stages of the backswing or the initial stages of the downswing. As discussed above, the light tracings generated by the White, Cunningham or Apthorp practice devices, does not provide this type of interpretative information.

In order to achieve the foregoing, and in accordance with one embodiment of the present invention, a golf swing practice device is provided for use with a golf club having a club head and a club shaft, comprising: a carrier member having at least one light source which is mounted so as to project a beam of light in a direction away from the club head so that said light source projects a beam of light on the ground during the later stages of the backswing and during the initial stage of the downswing, and wherein, said light source projects a relational image on the ground, which relational image provides an indication of the position of the club face of the club head.

Preferably, the light source is mounted in a position which is essentially parallel to, and preferably, essentially coaxially with, the club shaft.

DESCRIPTION OF THE INVENTION

The relational image projected on the ground may be any of a series of shapes and sizes, such as an image of the club head, a triangle, an oval, or the like, but most preferably is a line of light projected from a single light source. A circular pattern would not be usable since it would not provide feedback regarding the position of the club face, unless some other markings were included. Thus, the term "relational" is used to describe an image which can be used to provide information on the orientation of the light source, and thus, the position of the club head.

Alternatively, two or more light sources could be used to project two or more points of light in a distinctive pattern so as to create a relational image which would also provide an indication of the position of the club face during the later portions of the backswing or the initial portions of the downswing. Preferably, the light source projects an image of a line. At address, it has been found that a preferred arrangement has a line of light which projects a line of light which extends up the chest of the user, and which is essentially parallel to the spine of the user. As the club rotates around the user in a golf swing (when the golf club is kept on plane, and square to the target), the relational image from the light source will project an image on the ground during the later stages of the backswing, or during the initial stages of the downswing. For example, when the lead arm (i.e. the arm of the user closest to the target) of the user is essentially parallel to the ground on the backswing or downswing, the light source will, when the club is on the correct plane, project an image on the ground, which will fall at or near the ball, or the target line of the intended line of flight of the ball (which includes an extension of the line of flight, behind the ball).

With the preferred light source arrangement wherein the light source projects a line of light essentially parallel to the spine of the user at address, the light source will project a line of light which is essentially parallel to the target line when the lead arm of the user is parallel to the ground. Thus, when a golf swing has been executed wherein the club face is kept square to the target, and the club is kept on line, the light source will project a line on the ground which is parallel to, and preferably on, the intended target line, or extension thereof, of the ball flight.

Should the club face be open or closed during the backswing or the downswing, the line of light will not be parallel to the intended target line. Any suitable sources of light can be employed as the light source or sources.

This includes devices such as, for example, light emitting diodes (LED's) or lasers provided they emit sufficiently strong discrete beams of light to illuminate the ground. Preferably, however, the light sources are laser light sources, and preferably are laser diodes which have a wave length of 635-688 mm and maximum output of 5 mW, such as those used in known laser pointers used for instructional purposes. These devices have been found to be ideally suited for use in the present invention since the visual beam is red and is not generally affected by ambient light.

The golf swing practice device of the present invention is preferably adapted to be releasably attached to any standard golf club, which can include golf clubs generally described by golfers as putters, irons or woods. However, the golf swing practice device of the present invention can be permanently attached to a golf club in order to provide a practice club which would generally be unsuitable for use during a game of golf (since its use would violate the current rules of the game). Alternatively, the golf swing practice device could be attached to a foreshortened golf club, or even to a foreshortened golf shaft with grip without a club head (in which case the club head would be imaginary). In this fashion, a practice device is provided which could be used in height restricted locations while still providing feedback on the position of the (imaginary) club face. Thus, the term golf club is used to include these options of a dedicated golf swing training device, and a foreshortened club, with or without a club head.

The device of the present invention can be used in combination with other known devices used for indicating the position of the club face at impact, such as the devices of White, Cunningham, or most preferably, the device of Apthorp, described hereinabove. Thus, the device of the present invention can be used in combination with a device having a carrier member which can be removably attached to a shaft of a golf clubs and which is preferably attached to the lower portion of the hand grip which is itself mounted on the free end of the shaft. First and second lower light sources, preferably lasers, are mounted on the carrier and so positioned thereon to emit therefrom two spaced apart and parallel discrete beams of light in a direction towards the head of the club. The two light sources on the carrier are located on either side of the shaft when the carrier is attached to the shaft or grip, and are so positioned that the two light beams emitted therefrom together lie in a plane which bisects a club face of the club head at a right angle.

Again, the golf club of this combined golf swing practice device could be a dedicated golf swing training device with all light sources permanently or releasably attached, or could be a foreshortened club with or without a club head. In the embodiment where a club head is not present, an additional light source might be used to project an image such as a club head, or a line, which would represent the position of the club face.

Further, an alignment light source could be added to the device of the present invention which would provide a light beam projected onto the ground, at address, that would provide an indication of whether the club face was square at address, and provide an indication of whether the device of the present invention was properly mounted on the golf club. This additional alignment light source would also project an image onto the ground such as, for example, a line or the image of a club face, or the like.

Additionally, the device of the present invention can be used in combination with a mat or other device which provides one and preferably two spaced apart parallel lines on the ground, which represent the desired target line a hit ball should follow. These lines can be usefully employed in interpreting the image projected onto the ground, in order to determine whether the club face is open, square, or closed during the later stages of the backswing, or the initial portions of the downswing.

Due to mounting considerations, the carrier member of the device of the present invention is preferably attached to the golf club so as to minimize any interference with the golfer's grip on the club. For example, the carrier member might simply "clamp" on to the free or proximal end of the grip, or an extension thereof, or may be clamped onto the lower end of the grip, or the upper part of the exposed shaft, and also connected to the free or proximal end of the shaft by elongated connection means which connects the carrier member to a hole which is invariably located in the free end of the hand grip attached to the shaft.

Other features of the present invention, as well as other objects and advantages attendant thereto, are set forth in the following description and the accompanying drawings in which like reference numerals depict like elements.

DESCRIPTION OF DRAWINGS

In the accompanying drawings, an embodiment of the golf swing practice device of the present invention and its use are described, together with comments on how the light tracings on the ground can be used for interpretative purposes, wherein:

FIG. 1 is a perspective view of a preferred embodiment of the practice device of the present invention, including the positioning of the three light sources when the device is attached at two locations to a hand grip of a golf club;

FIG. 2 is a top plan view of the upper light source of the device of Fig. 1; and FIG. 3 is a rear illustrative view of a golfer's swing arc and the ground tracing of the upper light source relative to the desired target line; and

DETAILED DESCRIPTION OF DRAWINGS

The golf swing practice device of the present invention is preferably used in combination with a practice device which provides an additional indication of the club head position at impact, such as the device of Apthorp described in US Patent No. 5897441. Accordingly, the golf swing practice device 1 shown in FIG. 1 is essentially identical to the practice device described by Apthorp, with the exception of the upper light source.

Practice device 1 is illustrated relative to its mounting location on the hand grip 42 of golf club 40; the golf club 40, golf club shaft 41 and hand grip 42 being shown in broken line.

In accordance with the device of Apthorp, practice device 1 consists of a carrier member 2 having two spaced apart light sources mounted thereon and which are also illustrated in broken line at 3 and 4, and which respectively direct parallel beams of light indicated by lines 5 and 6 towards the distal end of shaft 41. Carrier member 2 is made up from a C-shaped section 7 and limb elements 8 and

9 which are each respectively attached to a free end of C-shaped section 7. The opposed and inwardly directed limbs of elements 8 and 9 at their respective free ends are provided with curved clasping elements 10 and 11 which serve to removably attach carrier member 7 to shaft 4. The spatial distance between the clasping elements can be varied so that the carrier can be readily attached and removed from hand grip 42. To this end, curved clasping element 11 can remain fixed to the limb of element 8 while clasping element 10 is permitted to move inwardly and outwardly by simply rotating tubular sleeve 12 which is threadedly connected to element 8 in a manner which is well understood in the art. As illustrated, limbs 8 and 9 at the end of C-shaped section 7 also each extend downwardly and have internally located therein, light sources 3 and 4 illustrated in broken line which emit discrete beams of light depicted by lines 5 and 6.

Carrier member 2 is also attached to the upper or proximal end of the golf club employing a second elongate connector 13 which at one end is fixed to carrier member 2 as shown in FIG. 1 and which at its other end, terminates at projecting pin 14 which can be inserted in a hole 15 which is located in the top end of the hand grip 42 as illustrated. Connector 13 along its major length is spaced from grip 42 a sufficient distance to enable the clasping of hand grip 42 without interference.

Second connector 13 at its end which attaches to grip 42 also preferably is used to support an upper light source 16 which is oriented so as to be coaxial with shaft 41, and which projects direct a discrete line of light away from the club head in a direction opposite to parallel light beams 5 and 6. In Fig. 2, the light source 16 is shown in detail so as to indicate that it contains a slot 21 which would provide for a line of light to be emitted from the light source. As described earlier, other images could be used, and the images could be rotated, and/or replaced with other images which would provide a relational image to be projected. As shown in Fig. 1, the light projected from upper light source 16 is projected through slot 21 to provide for the projection of light generally shown by broken lines 22 and 23, to produce a line of light 24 which is projected from the upper light source. In the embodiment shown, the line of light 24, would be projected on the chest of the user, when the device was at address, in a line essentially parallel to the spine of the user. The power supply for light sources 3, 4 and 16 can comprise battery power with two such batteries being illustrated in series and located internally of the second connector 13 as illustrated in broken line at 18. Switch 19 is used to turn the power supply for the light sources on and off in a well known manner.

Use of the parallel beams of light 5 and 6, emitted from light sources 3 and 4, is described in detail in US 5897441, the contents of which are hereby incorporated by reference. No further discussion of their use is necessary for the purposes of the present invention.

In Fig. 3, the ground tracking of the line of light 24, is illustrated. A golfer 30 using the practice device 1 of the present invention is shown in a position near the top of the backswing (which is essentially identical to the position of the golfer at the initial stages of the downswing). The preferred plane of the swing is generally depicted as 31. Although some variation from this ideal plane is likely, particularly at the initial stages of the swing, it is a good visual concept to follow this plane 31 as closely as possible throughout the swing. When the golfer reaches the position of the swing shown in Fig. 3, light depicted as 22 to 23 is emitted from the upper light source 16 so as to produce a line of light 24 on the ground. If the club head is square to the target, line 24 will be essentially parallel to the line of the target. As the golfer completes the backswing, the line of light will move further back behind the golfer, but will remain on a line parallel to the line of the target. - lo ¬

re should be noted that this line of light 24 can be observed by the golfer, or by a second party, who can use the information to determine the position of the club face during the backswing.

As the golfer starts the downswing, the light of light 24 will move from behind the golfer, and will pass through the golf ball 25, and then move in front of ball 25. At all times, however, the line of light should remain essentially parallel to the target line, and preferably will remain on the target line.

The tracings of upper light source 16 (and light beams 5 and 6) may be merely projected on to the ground. However, it is preferred that the light be projected on to a thin practice strip or runway such as a length of plastic sheet material 20 or the like having spaced apart parallel markings thereon (86 and 90), and which can be orientated so as to represent the desired target line. With the use of this practice strip 20, it is easier for the golfer or an observer to confirm that the line of light 24 remains between and parallel to, lines 86 and 90. Thus, it is apparent that there has been provided, in accordance with the present invention, a golf swing practice device, which fully satisfies the means, objects, and advantages set forth hereinbefore. Therefore, having described specific embodiments of the present invention, it will be understood that alternatives, modifications and variations thereof may be suggested to those skilled in the art, and that it is intended that the present specification embrace all such alternatives, modifications and variations as fall within the scope of the appended claims.

Further, it will also be appreciated that while I have advanced a particular form of construction which is intended to achieve the end objects of my invention, various alterations and changes can be made to it which do not depart from the spirit or scope of my invention.

Additionally, for clarity and unless otherwise stated, the word "comprise" and variations of the word such as "comprising" and "comprises", when used in the description and claims of the present specification, is not intended to exclude other additives, components, integers or steps.

Claims

We claim:

1. A golf swing practice device for use with a golf club having a club head and a club shaft, comprising: a carrier member having at least one light source which is mounted so as to project a beam of light in a direction away from the club head so that said light source projects a beam of light on the ground during the later stages of the backswing and during the initial stage of the downswing, and wherein, said light source projects a relational image on the ground, which relational image provides an indication of the position of the club face of the club head.

2. A golf swing practice device as claimed in Claim 1 wherein said relational image is a line of light.

3. A golf swing practice device as claimed in Claim 1 wherein said light source is mounted essentially parallel to said club shaft.

4. A golf swing practice device as claimed in Claim 3 wherein said light source is mounted essentially coaxially with said club shaft.

5. A golf swing practice device as claimed in Claim 1 , wherein said light source is a solid state laser.

6. A golf swing practice device as claimed in Claim 1 , wherein said club head is imaginary.

7. A golf swing practice device as claimed in Claim 1, in combination with one or more light sources which provide an indication of the position of the club face at impact.

8. The golf swing practice device as claimed in claim 1 , in combination with a thin elongate strip for placement on the ground and which on the upper face thereof includes two spaced apart and parallel lines which represent the desired target line of a golf ball.