Abstract:
The golf swing training device has a foreshortened shaft, a grip mounted on the upper end of the shaft, a head mounted on the lower end of the shaft, a first laser module mounted in the grip end of the shaft for directing a laser beam upwardly from the grip in co-axial alignment with the central axis of the shaft, and a pair of laser modules mounted in the head of the training device for directing a pair of spaced parallel laser beams downwardly from the head in a diametrically opposed direction from the beam emanating from the grip. The two beams projecting from the head of the training device are disposed in a common plane with a downward extension of the central axis of the shaft such that a line drawn between the points of impact of the beams on the ground visually defines the footprint and thus the angular orientation of an imaginary club face. The laser carrying head is configured so that it can not be used to strike a golf ball. The training device also includes a momentary on-off switch mounted in the grip for activating the laser modules upon the golf training device being held in a conventional golf grip. The method includes gripping the golf training device and performing a golf swing while observing the laser beams to train a consistent golf swing.

Description:
This is a continuation-in-part of application Ser. No. 09/033,438 filed on Mar. 2, 1998 and entitled Dual Ended Laser Swing Aid, which is based for priority on Provisional Patent Application No. 60/038,564, filed Mar. 3, 1997. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to training devices which assist a golfer in learning to correctly swing a golf club and a training method using such devices. More particularly, the invention relates to golf swing training devices equipped with a plurality of lasers to provide an optical indication of the complete swing path action of a golf club, including the take-away, back swing and down swing as well as the orientation of the club face during the swing. 
     Training aids designed to assist golfers in developing a proper golf swing have included arm braces, gloves, tubular tracks and many other devices. More recently, optical devices using lights and lasers have been proposed. An example of such a device is found in U.S. Pat. No. 5,848,941 issued to Morra which, although not prior art, discloses a particularly configured golf club having two small lights or lasers pointed in axially opposed directions, one being mounted in the upper end of the shaft and the other in the club head. By viewing the paths of light emanating from the club head and grip while striking a ball, the path of the club during the swing is visually represented. This allows one to see the variances in their swing from a proper swing plane and thus assists the golfer in learning how to correct his or her swing. However, the inclusion of the golf club head on the device may obscure the laser beam emanating from the lower end of the shaft and the shock of the impact of the head with a golf ball is likely to quickly damage the laser module in the club head. Another swing training device employing opposed lasers is found in applicant&#39;s copending application Ser. No. 09/033,438 entitled Dual Ended Laser Swing Aid. In that device, the shaft is shortened from the length of a regular golf club so that the head of the device will not visually obstruct the path of light emanating from the lower laser at the point of impact. The head on the device is configured so that it can not be used to actually strike a ball and is particularly weighted to give the foreshortened device the weight and balance of a conventional golf club. 
     While the aforesaid devices are very useful in teaching one the proper swing plane of a golf club, they do not provide the user with any feedback regarding the angular orientation of a club head during the swing. It is well known that even if a club is swung on a proper plane, an open club face at the point of impact with the ball will cause a ball to fade or even slice and a closed club face will cause the ball to draw or hook. Thus, while the instructional devices heretofore available may teach one how to swing the club on plane, they do not tell the user whether or not their club head would be square to the ball at impact which is necessary to execute a straight shot. It would be highly desirable if a golf swing training device not only enabled the golfer to visualize the golf club path to perfect a proper swing plane, but also provides the golfer with a visual representation of the orientation of the club head during the swing and, most importantly, through the point of impact with a ball. Such a device is found in the present invention. 
     SUMMARY OF THE INVENTION 
     Briefly, the golf swing training device of the present invention comprises a foreshortened shaft, a grip mounted on the upper end of the shaft, a head mounted on the lower end of the shaft, a first laser module mounted in the grip end of the shaft for directing a laser beam upwardly from the grip in co-axial alignment with the central axis of the shaft, and a pair of laser modules mounted in the head of the training device for directing a pair of spaced laser beams, preferably parallel, downwardly from the head in a diametrically opposed direction from the beam emanating from the grip. The two beams projecting from the head of the training device are disposed in a common plane with a downward extension of the central axis of the shaft such that a line drawn between the points of impact of the beams on the ground visually defines the footprint and thus the angular orientation of an imaginary club face. The shaft on the training device is substantially shorter than a conventional golf club shaft so that head is elevated from the ground so as not to obscure the golfer&#39;s view of the laser beams through the point of impact. The laser carrying head is preferably configured so that it can not be used to strike a golf ball which would damage the laser modules mounted therein and is weighted so as to give the training device with its foreshortened shaft the weight and balance of a conventional golf iron. The training device also includes a momentary on-off switch mounted in the grip for activating the laser modules upon the golf training device being held in a conventional golf grip. 
     The method of the present invention includes gripping the golf training device of the present invention and holding the training device in the customary “address” position, whereby the two lasers in the head will direct beams of light against the ground at the location where a golf ball would be if one were going to actually hit a ball with a conventional club. An imaginary line between the two illuminated dots (where the laser beams strike the ground) provides a visual indication of the angular orientation of an actual club face at the address position. By holding the training device with a conventional golf grip at the ball address position such that this imaginary line is square to the intended direction of ball flight and swinging the device in the same manner as one would swing a conventional club, a visual representation of the swing and club head orientation is provided to the golfer by the three lasers. 
     During the back swing of the training device, the laser beams emanating from the head and striking the ground will visually illustrate the path of the take-away portion of the swing and the orientation of the club head during the take-away. As the swing continues rearwardly, the single laser beam emitted from the grip end of the shaft illustrates the target or take-away line and thus cooperates with the two lasers in the head to define the swing plane of the rearward portion of the golf swing. On the down swing, the grip laser shows the target line and in cooperation with the two head lasers, illustrates the swing plane of the down swing. At the finishing point of the down swing, before impact with an imaginary ball and prior to the follow through, the two head lasers will not only show the swing plane line through the target line to impact, they also provide a visual representation of the orientation of a club face with respect to the ball location as the golfer swings the training device through the imaginary point of impact, thus also providing the golfer with information regarding the positioning of the hands through the swing. Finally, the path of the club at the “finish” of the swing is illustrated by the grip laser as its beam passes through the contact area. As a golfer should always look at the ball until impact, the golfer alone can observe all of the laser tracks provided by the training device through the impact area with or without the help of a video camera. If the laser lines do not conform to the correct paths and alignment, the golfer has a set of diagnostics on how to correct the various parts of the golf swing. 
     It is therefore the principal object of the present invention to provide an improved training device which assists the golfer in correcting his or her golf swing. 
     It is a another object of the present invention to provide a golf swing training device which provides a continuous indication of the location and attitude of the grip and head of the golf club during a complete golf swing to provide a visual representation of the swing path of the club to assist the golfer in perfecting his or her swing. 
     It is a further object of the present invention to provide a golf swing training device which tracks the angular orientation of the club face produced by the swing through the point of impact to assist the golfer in learning the proper use of his or her hands and wrists during the swing. 
     It is another object of the present invention to provide a golf swing training device which has the weight and balance of a conventional golf club and provides an unobstructed visual representation of the swing path and angular orientation of the club face throughout the golf swing. 
     It is still another objection of the present invention to provide a golf swing training device which is self-acting, portable and suitable for golfers of all sizes, ages, right-handed or left-handed, and both genders. 
     It is yet another object of the present invention to provide a golf swing training device which is rugged, economical to manufacture, and simple to use both indoors or outdoors. 
     These and other objects and advantages of the present invention will become readily apparent from the following detailed description of the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the golf swing training device of the present invention. 
     FIG. 2 is a partial perspective view of the golf swing training device of the present invention. 
     FIG. 3A is a circuit diagram showing the electrical connections of the laser modules in a first embodiment of the invention wherein the shaft is employed as an electrical conductor. 
     FIG. 3B is a circuit diagram showing the electrical connections of the laser modules in a second embodiment of the invention wherein the shaft is not employed as an electrical conductor. 
     FIG. 4A is a partial sectional view of the golf swing training device of the present invention showing the electrical connections of the laser modules in the first embodiment of the invention. 
     FIG. 4B is a partial section view of the golf swing training device of the present invention showing the electrical connections of the laser modules in the second embodiment of the invention. 
     FIG. 5A is a perspective view of the grip end cap and laser assembly employed in the first embodiment of the present invention. 
     FIG. 5B is a perspective view of the grip end cap and laser assembly employed in the second embodiment of the present invention. 
     FIG. 6A is a pictorial view of a golfer utilizing the golf swing training device of the present invention and illustrating the traces of the pair of lasers in the head end of the device to provide a visual representation of the swing plane and the orientation of an imaginary club head. 
     FIG. 6B is a pictorial view of a golfer utilizing the golf swing training device of the present invention and illustrating the trace of the single laser in the grip end of the device to provide a visual representation of the swing plane and the orientation of shaft. 
     FIG. 7A is a pictorial view of a golfer illustrating the golf swing training device of the present invention at the point of impact with the club head misaligned in an open position. 
     FIG. 7B is a pictorial view of a golfer illustrating the golf swing training device of the present invention at the point of impact with the club head misaligned in a closed position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now in detail to the drawings, the golf swing training device  10  of the present invention comprises a head  12 , shaft  14  and grip  16 . The head  12  is a solid mass, preferably of a cylindrical configuration so that it seriously discourages its use to actually strike a golf ball but properly weighted so as to give the golf swing training device  10  the weight and balance of a conventional golf iron. 
     The head  12  of training device  10  defines a pair of cylindrical channels  18  and  20  therein for housing a pair of head laser modules  22  and  24 . A suitable laser module that is currently being utilized in the training device is a Class 3A laser, 645 nm, manufactured by Syndex Technical Supplies, Ltd. of Taiwan but any appropriate laser may be used. The channels  18  and  20  in which the head laser modules are mounted extend into the head  12  from the lower end  12 ′ thereof and preferably are in parallel alignment and coplanar with a projected extension  26   a  of the central axis  26  of the shaft  14  as illustrated in FIG.  1 . The laser modules  22  and  24  are held within channels  18  and  20  respectively by press fitments and thereby positioned such that the laser beams  22 ′ and  24 ′ emanating from the head lasers will project from the lower end  12 ′ of head  12  through the open channel ends in a spaced parallel relationship with the parallel beams also being parallel to and coplanar with the forward extension  26   a  of the central axis  26  of shaft  14 . As an alternative, one or both of the laser modules  22  and  24  may be positioned to point the laser beam  22 ′ and/or  24 ′ at an angle to the extension  26   a  of the axis  26  of shaft  14 , such as, for example, at a small angle to but coplanar with extension  26   a , or both laser beams  22 ′ and  24 ′ at the same angle slightly forward of extension  26   a , or the like, such that a plane or line is created by or between the two laser beams  22 ′ and  24 ′ that may be observed by the golfer while practicing his or her golf swing with the device  10 . In the preferred embodiment, head  12  is formed by injection molding or casting and small tapered fins (not shown) are provided to form the press fitments of the laser modules within the channels and provide electrical ground contacts between the outer casings of the laser module and the head  12  when necessary, as will be explained. 
     The shaft  14  utilized in the present invention preferably is a foreshortened conventional hollow golf club shaft of about 24 to 30 inches in length, although any hollow shaft could be used. In a first embodiment of the invention, the shaft  14  is utilized as an electrical conductor and is thus formed of metal. In a second embodiment of the invention, the shaft is not so utilized and can be constructed of any suitable material. The shaft  14  is secured to the cylindrical head  12  by any suitable securement means. Threaded engagements of the shafts and heads are illustrated in FIGS. 4A and 4B. 
     A conventional golf grip appearance and material is provided on the exterior of grip  16  which has the closed end portion removed and is disposed about the upper end portion of shaft  14  as seen in FIG.  1 . Protruding from the external surface of grip  16  is a momentary on-off switch  28  which is convenient relative to the golfer&#39;s hands such that when the training device  10  is held by a golfer in a conventional golf grip, switch  28  will be depressed to close the D.C. electrical circuit inside shaft  14  and activate the laser beams in a manner to be discussed. For safety reasons, switch  28  is spring loaded and must be held in a depressed state for the lasers to activate. When the golfer removes his hands from the grip and releases the switch, the switch will open the D.C. circuit and deactivate the lasers. 
     A grip knob  30  is attached to the free end of the shaft  14  which houses a grip laser module  32  which generates a grip laser beam  32 ′. The grip knob  30  is removably attached to the upper end of the shaft for installation of the D.C. power to activate the laser modules  22 ,  24  and  32 . 
     Referring to FIGS. 3A and 4A, a circuit diagram and an exploded cross-sectional view of the first embodiment of the invention are shown wherein the D.C. power source for the laser modules is provided by a pair of 1.5 volt batteries  36  and  37  mounted in series in the upper end of shaft  14 . The head laser modules  22  and  24  are in electrical communication with batteries  36  and  37  via hot wires  38  and  40  (or alternatively both laser modules connected to a single common wire) which are connected to and extend from the negative hot terminals  42  and  44  of laser modules  22  and  24  respectively, through grip  16  to bridging terminal A of switch  28  (See FIG.  3 A). Battery hot wire  46  is affixed to and extends from a connector  47  in electrical communication with the negative pole of lower battery  36  to D.C. power source terminal B of switch  28 . Switch wire  48  extends from terminal C of switch  28  to an electrically conductive pin or coil spring  50  mounted in a shaft fitting  51  on the upper end of grip  16  and projecting slightly therefrom as seen in FIG.  4 A. When the grip knob  30  is mounted on shaft fitting  51 , coil spring  50  is pressed against and in electrical communication with an annular conductor ring  52  on grip knob  30 . Ring  52  is in electrical communication with the negative hot terminal  54  of grip laser module  32  via hot wire  55 . 
     The grip knob  30  also includes a ground circuit completion spring  56  which, as seen in FIGS. 4A and 5A, defines an annular slotted base portion  58  and arm portion  60 . As best seen in FIG. 5A, the base portion  58  extends about and grips the positive ground case  34  of grip laser module  32 . Arm portion  60  projects downwardly adjacent laser module  32 , bends inwardly at  62  and again at  64  to define an axially extending arm portion  66 , an inclined arm portion  68  and a radial arm portion  70 . Through such a configuration, the circuit completion spring  56  electrically communicates the positive ground case  34  of laser module  32  with the electrically conductive shaft  14  along the axially extending arm portion  66  of the spring and with the positive ground pole  72  of upper battery  37  via the radial arm portion  70  of circuit completion spring  56 . The positive ground of the D.C. circuit is completed by the electrical communications between the positive ground casings of head laser modules  22  and  24 , head  12  and shaft  14 . The momentary switch  28  closes and opens the D.C. circuit at terminals A and B, as shown in FIG.  3 A. Finally, grip knob  30  is preferably provided with external threads  74  on a reduced diameter portion of the knob adjacent conductor ring  52  which threadably engage internal threads  76  in the shaft fitting  51  on the upper end of grip  16  to provide the detachable connection of the grip knob. A centrally disposed aperture  80  is provided in the end surface of grip knob  30  to allow for the passage of the grip laser beam  32 ′ therethrough. 
     An alternate embodiment of the present invention is illustrated in FIGS. 3B,  4 B and  5 B wherein the shaft  14  is not utilized as an electrical conductor. The alternate embodiment of the present invention differs from the prior embodiment in that a pair of ground wires  90  and  92  (or alternatively a single, common wire) extend from ground connections  94  and  96  on the head laser modules  22  and  24  through shaft  14  and grip  16  to a ground ring contact  98  mounted in the shaft fitting  51  on the upper end of grip  16  in axial alignment with shaft  14 . Ring contact  98  engages the axially extending portion  66  of the ground circuit completion spring  56  to effect the electrical communication of ground wires  90  and  92  with spring  56 . Finally, a ground wire  99  provides an electrical communication between ground contact  101  on the grip laser module  32  and spring  56 . In this embodiment, the head  12  and shaft  14  need not be of electrically conductive materials. The operation of the second embodiment of the device by switch  28  is identical to the operation of the prior embodiment. 
     The use of the golf training device  10  of the present invention is illustrated in FIGS. 6A and 6B, which separately illustrate the path of the pair of lasers beams  22 ′ and  24 ′ (FIG. 6A) and the single laser beam  32 ′ (FIG. 6B) for clarity, although it will be understood that the paths of all three laser beams will be traced simultaneously in each golf swing. As shown in FIG. 6A, the golfer G is holding the training device  10  at the correct address position P 1  with the laser head beams  22 ′ and  24 ′ oriented with respect to an imaginary ball  200 , such that an imaginary straight line  202  drawn between the illuminated points of impact of laser beams  22 ′ and  24 ′ on the ground or floor is normal to the target line  203  and the intended flight path of the ball. It should be noted that for creating a larger separation of the points of contact on the ground of the laser beams  22 ′ and  24 ′, one or both of the laser modules  22  and  24  may be angled slightly away from axis extension  26   a  for thereby accentuating the position of the imaginary club face and making it more visible without making the head  12  larger. The orientation of the club face can also be seen by the relative positioning of the points of impact of laser beams  22 ′ and  24 ′ on the ground through the impact area, i.e., prior to and following the point of impact with a ball if an actual golf club were being used to strike a golf ball with the same swing. As the training device  10  is moved rearwardly in the take-away portion of the golf swing, the head  12  begins to rotate as the golfer&#39;s hands and arms rotate (as in a preferred golf swing) which is evident from the position P 2  of the device and the laser beams  22 ′ and  24 ′ wherein the line  202  therebetween is no longer perpendicular to the target line  203  and is at a small angle to the dot-dash line D simulating the motion of an actual club head. As the backswing continues to position P 3  where the shaft is approximately horizontal, the head  12  is rotated to a desired orientation where the line  202  between laser beams  22 ′ and  24 ′ is substantial vertical and coincident with the dot-dash line D. This orientation of the laser beams  22 ′ and  24 ′ relative to the dot-dash line D, i.e. both beams stay on the line D, preferably continues through the backswing in positions P 4  through P 10  and again in the downswing of positions P 10  through P 3 , whereupon the head  12  starts turning back to the desired orientation of the line  202  between the laser beams  22 ′ and  24 ′ being perpendicular to the target line  203  and dot-dash line D. Thus, the golfer can see the results of his or her hand and wrist movements on the face of the club head and thereby learn the proper positioning of the hands and wrists during this critical portion of the swing. By practicing with the golf training device indoors or proximate front and rear walls and a ceiling or overhead wall, one can view the orientation of the club face throughout the entire swing as is pictorially represented by the pairs of dots along the dot-dash line in FIG.  6 A. 
     Referring now to FIG. 6B, the path of the single grip laser beam  32 ′ is illustrated for the relevant positions corresponding to the like-numbered positions in FIG.  6 A. At the address position P 1 , the laser beam  32 ′ assumes a location  11  on the golfer&#39;s midsection. During the start of the take-away, the location of laser beam  32 ′ is above and forward of the golfer and unrelated to the various positions of the pair lasers  22 ′ and  24 ′ during the golf swing. As the shaft  14  of training device  10  passes horizontal to position P 4  and beyond the laser beam  32 ′ will become visible and at position P 5  the location L 5  of the laser beam  32 ′ is preferably on the target line  203 . During the continued backswing through positions P 6 -P 10  the laser beam  32 ′ will be at the locations L 6 -L 10 , respectively, on a swing path of dot-dash line D′ that preferably is substantially the same as dot-dash line D of FIG.  6 A. In other words the grip laser beam  32 ′ should trace the same path as the head laser beams  22 ′ and  24 ′ through those portions of the swing path in which the laser beams overlap thereby assuring a consistent and preferred golf swing. 
     FIGS. 7A and 7B illustrate the visual representation of improper club head alignment at address provided by the golf training device  10 . As seen in FIG. 7A, laser beam  24 ′ is ahead of laser beam  22 ′ such that an imaginary line  206  drawn therebetween is not normal to the target line  203  but is normal to a line  208  pointed outside the target line, indicative of an open club face which can produce a fade or slice. In FIG. 7B, the imaginary line  210  normal to the line  212  drawn between the points of impact of laser beams  22 ′ and  24 ′ on the ground indicates a closed club face which can produce a draw or hook. By practicing one&#39;s swing with device  10 , the desired square club face orientation illustrated in FIG. 6 can be more readily learned. In addition, slightly open and closed club face positions can also be learned to teach one how to fade or draw a golf ball. 
     In addition to providing a visual representation of the club face during the golf swing, the head and grip laser modules also provide a pictorial representation of the entire swing to assist the golfer in learning the proper club orientation or swing plane of the club during the swing. In the correct take-away position, the head laser beams  22 ′ and  24 ′ will indicate a straight take-away line during the initial motion of the back swing and thus follow the rearward extension of imaginary line  202  of the FIG.  6 . During the back swing, the grip laser beam  34  should trace a line which coincides with the same path followed by the head lasers thereby illuminating a path which traces out the path of a club head during the back swing so that by following the paths traced by the head and grip laser beams, the proper back swing can be learned. During the down swing, the grip laser should trace a path which coincides with the original back swing line which should then be followed by the head laser beams. Thus, the golfer can utilize the training device  10  to practice the entire swing or to concentrate only on the portion of his or her swing which deviates from the correct motion. Repeated swings with the training device  10  will serve to remedy any bad habits and the golfer can do so alone whenever and wherever it is convenient. Installation and exchange of the batteries  36  and  37  is also made easy and straightforward by the provision of the readily detachable and replaceable grip knob  30  and the ground circuit completion spring  56  employed therein. 
     Various changes and modifications may be made in carrying out the present invention without departing from the spirit and scope thereof. Insofar as these changes and modifications are within the purview of the appended claims, they are to be considered as part of the present invention.