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(11) | EP 0 057 467 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Golf swing practicing machine |
| (57) A golf swing praticing machine includes a doughnut shaped main frame which has on
its entire circumference a circular face that is parallel to a golf club and player's
arms and is gradually inclined from outside to the center. The main frame further
has a center opening at its center and the upper half of the main frame is bent forward.
The main frame is set up in a backwardly inclined state and on the front surface of
the circular face are shown three loci indicating the clubhead arcs of backswing,
downswing and follow-through and a plurality of straight lines indicating clubshaft
arc. When a player swings his golf club along the circular face, the above-mentioned
loci move laterally according to the player's weight shift producing substantially
an elliptic swing arc. |
BACKGROUND OF THE INVENTION
1. Field of the Invention
2. Prior Art
[0002] Practicing of the golf swing is usually done in accordance with the instructions shown in a textbook or given by a coach. Therefore, it is likely that swing would be made only by the arms and wrists, resulting in a rough swing.
[0003] There has been provided a practicing machine which is made up of elliptically assembled rods. With this type of machine, one can practice swinging his club along its elliptical frame. With this practicing machine a player can swing his club along its elliptical path only with his arms and wrists. Accordingly, it is extremely difficult to learn an ideal swing, such as one with a stable head as an axis, steady legs and with the waist turning fully.
SUMMARY OF THE INVENTION
[0004] Accordingly, it is a primary object of the present invention to provide a golf swing practicing machine with which one can learn an ideal golf swing easily.
[0005] In keeping with the principles of the present invention, the object of this invention is accomplished by a unique practicing machine in which an inclined elliptical plane is designed in a doughnut shape to enable it to lead the clubhead and clubshaft along the ideal swing arc. The practicing machine is further provided in its inclined doughnut shape plane with plurality of laterally arranged circular locus, which can assist the player in shifting his weight, in stabilizing his head and in efficiently twisting his entire body, thus producing the ideal golf swing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The above-mentioned features and object of the present invention will become more apparent with the following description of the invention in conjunction with the accompanying drawings, wherein like reference numerals denote like elements, and in which:
FIGURE 1 is a perspective view of the.golf swing practicing machine in accordance with the teachings of this invention; showing it in the state of being used;
FIGURE 2 is a front view of the machine;
FIGURE 3 is a sectional side view thereof;
FIGURE 4 is a front view of a base plate;
FIGURE 5 is a sectional side view thereof;
FIGURE 6 is a diagram showing the way to draw the swing arc;
FIGURE 7 is an illustration of the swing arc. which is provided according to the present invention;
FIGURE 8 is a sectional side view of another embodiment of this invention; and
FIGURE 9 is a front view showing another embodiment of this invention.
DETAILED DESCRIPTION OF THE INVENTION
[0007] As can be seen in Figures 1_to 3, a main frame 5 is provided with a circular face 3 which is gradually inclined backwardly toward the center and is parallel to a clubshaft 1 and arms 2 of a player 23. The upper-half of the circular face 3 is bent forwardly at an adequate angle; the main frame 5 is further provided with a center opening 4. The main frame 5 is placed in front groove 7 of a base plate 6 so that the main frame 5 is free to convert its inclination angle by a support member 8. The circular face 3 has a bent-up angle C as shown in Figure 3.
[0008] On the entire or partial circumference edge of the main frame 5 is provided a rim 9 which is inserted in the front groove 7. The rim 9 indicates the swing arc of the clubhead. Provided at the center of the front groove 7 of the base plate 6 is a marker 10 which sets the clubhead into the proper position. On the base plate 6 is further provided a hollow groove 12 in which a mat 11 is placed. A shoulder pad 13 is provided adjacent the hollow groove 12 of the base plate 6. The shoulder pad 13, whose height is adjustable, indicates the proper shoulder position at the top of the swing. The base plate 6 is further mounted with a pair of foot pads 14.
[0009] On the circular face 3 and rim 9 are provided loci, shown in Figure 7 which can be drawn according to the diagram of Figure 6.
[0010] More specifically, each of the three vertical lines 15, 16 and 17 which are parallel with one another is provided with two points 15a, 15b, 16a, 16b, 17a and 17b, respectively. An inner locus 15c which is drawn around the upper point 15a of the left-side vertical line 15 indicates the grip arc of the golfclub in backswing; while outer locus 15d drawn around the lower point 15b indicates the clubhead arc made from address to the top of the backswing. The inner locus 16c which is drawn around the upper point 16a of the central vertical line 16 indicates the grip arc of a golfclub in downswing; while the outer locus 16d drawn around the lower point 16b indicates the clubhead arc made from address to the top of the downswing. The inner locus 17c which is drawn around the upper point 17a of the right- side vertical line 17 indicates the grip arc of a golfclub in follow-through; while the outer locus 17d drawn around the lower point 17b indicates the clubhead arc made from address to the top of the swing. Then, each of the inner loci 15c, 16c and 17c and outer loci 15d, 16d and 17d are connected with a plurality of straight lines 18 which are shown by dividing the clubshaft arc into equal intervals.
[0011] At the tips of the straight lines 18 are shown a clubface arc 19 which opens and closes at a fixed angle.
[0012] When eliminating certain parts, equal to a center opening 4, of the loci drawn according to Figure 6, the resulting loci having no inner locus 15c, 16c and 17c are the ones which are shown in Figure 7. The loci obtained by the way described above are shown on the circular face 3 and rim 9, as are shown in Figures 1 and 2.
[0013] As shown in Figure 6, all the points of intersection of the straight lines 18 showing the clubshaft 1 and the outer loci 15d, 16d and 17d of the clubhead arc are equidistant to each other. However, inter-sections of the straight lines and the inner loci 15c, 16c and 17c are dense at the center but gradually disperse outwardly, particularly the tops of the inner loci 15c, 16c and 17c are rather dispersed. At the top of the swing the clubface opens at the angle of 90° as shown in Figures 6 and 7, but at the top of the follow through the clubface closes at the angle of average 180° and the clubshaft is in an approximately horizontal position. In Figures 6 and 7, a white point is the vertical point of the central position 20 and the dotted line is the line of center 21. A slightly inclin-ed straight line 18a denotes the clubshaft at address, and the position of the ball is indicated as being at 22.
[0014] As is shown in Figure 3, it is preferable to set the angle a at 50° to 70°, the angle b approximately at 119° and the angle c at about 110.5°. The angles a and b can be converted when the main frame 5 is raised and lowered. The angle c can be adjusted by moving the upper-half of the main frame 5 up and downwardly; the position of the angle c may convert to some upper position as the length of the golfclub is shortened. The angular width of angle c is concerned with the clubface speed to open at 90°. If the clubface opens at 90° in a fast backswing, the angle c becomes wider; while, if the moment when the clubface opens at 90° delays, the angle c becomes smaller. Therefore, at the time when the clubface opens at 90° at the top of the swing, the angle c is minimized. On the other hand, the moment in which the clubface ope_ns at 130° in the follow through is almost the same everytime, having nothing to do with the downswing. The clubhead opens at 90° in the backswing and at the top of the swing, and closes at 180° in the downswing and the follow through.
[0015] As shown in Figure 1, the elliptical locus around the center 20 will not generate centrifugal force, but the circular locus showing backswing, downswing and follow through will generate centrifugal force. A square club swing is different from the mechanical circular motion. Therefore, according to the square club swing it is impossible to start the swing from the center of one circle and to start the swing with cocking the wrists.
[0016] There are in a golf swing two centers showing the center of the inside circle of the clubshaft arc and the center of the outside circle of the clubhead arc. A player swings his club freely within the two circles with his wrist cocking and uncocking. In the loci 15c, 15d, 16c, 16d, 17c and 17d of the backswing, downswing and follow through, there are upper and lower centers 15a, 15b, 16a, 16b, 17a and 17b on the vertical lines 15, 16 and 17 which are parallel to each other. When a player swings the club, the vertical line will laterally move toward 16 and 17 in sequence from line 15 position together with the shift of the player's body weight and the centers move from 15a and 15b to 16a and 16b and to 17a and 17b; as a result, the whole club swing draws an elliptical arc. At this moment, the vertical intervals between centers 15a and 15b, between 16a and 16b and 17a and 17b are not always the same. The position of the center 20 of the whole ellipse and the vertical line 16 differs sometimes from each other. The rotary angle of the club face opens and closes in an equal angle.
[0017] In use of the practicing machine described above, as is shown in Figures 1 and 2, the player 23 who practices golf swing sets up at the foot pad 14; namely, behind the center opening 4 of the main frame 5 and sets his golf club at the circular face 3 to make a practice swing along the loci shown on the circular face 3 and rim 9.
[0018] More specifically, when a player swings his club following the outer loci 15d, 16d and 17d indicating clubhead arc, the straight line 18 indicating the locus of the clubshaft 1 and the mark 19 indicating the arc of the clubface angle and along the circular face 3, each circular locus smoothly moving laterally according to the player's weight shift during the backswing, downswing and follow-through producing sufficient centrifugal force. The swing made according to the above-described way keeps the player's head steady; therefore, the player can learn an ideal golf swing in which his head functions as a swing axis and his whole body is turned sufficiently. It is incidentally, effective to set up mirrors in front of and on both sides of the main frame 5 when the player 23 practices golf swing with the above-described machine.
[0019] Shown in Figure 8 is another embodiment of the main frame 5 of the present invention. In this embodiment, a transparent flap 23, which is the same shape and size as the circular face 3, is secured spacedly in front of the circular face 3, forming a guide groove.24 therebetween. In practicing, the clubshaft may be guided by the guide groove 24. This embodiment can eliminate to show the straight lines which indicates the arc of the clubshaft 1. However, it is possible to show the above-mentioned loci and straight lines on the transparent flap 23.
[0020] Furthermore, as is shown in Figure 9, the three loci indicating the clubhead arcs in the backswing, downswing and follow-through and the straight lines indicating the-arc of the clubshaft 1 can be formed by a plurality of rods 25 which- are connected to one another.
[0022] The practicing machine of this invention is constructed in such a manner that the main frame provided with a circular face which is parallel to the clubshaft 1 and player's arms 2 and is gradually inclined backwardly from outside to its center and further provided with a center opening 4 in its center is placed on the base plate 6 in a backwardly inclined figure by its inclining angle adjustable by the supporting member 8. Therefore, a player 23, setting up behind the center opening 4, can swing his club along the circulr face 3 which is parallel to the clubshaft 1 and player's arms 2. Furthermore, the player 23 can easily recognize the swing arcs which are shown on the circular face 3 because the main frame 5 is inclined backwardly.
[0023] On the circular face 3 and rim 9 are shown outer loci 15d, 16d and 17d whose centers are respectively, the lower points 15b, 16b and 17b, which are marked on the vertical lines 15, 16 and 17. On the circular face 3 and rim 9 are also shown the straight lines 18 which indicate the arcs of the clubshaft 1 connecting the inner loci 15c, 16c and 17c, centers thereof are the upper points 15a, 16a and 17a with the outer loci 15d, 16d and 17d. Further shown on the circular face 3 and rim 9 are marks 19 which indicate the locus.of the club face angle. Therefore, during club swing above, each . locus moves laterally according to the weight shift of the player who makes backswing, downswing and follow-through producing efficient centrifugal force.
[0024] It should be apparent to those skilled in the art that the above-described embodiments are merely illustrative of but a few of the many possible specific embodiments which represent the applications of the principles of the present invention. Numerous and varied other arrangements can be readily devised by those skilled in the art without departing from the spirit and scope of the invention.
1. A golf swing practicing machine comprises a main frame inclined backwardly, said
main frame is provided with a circular face formed on the entire circumference of
said main frame, said circular face is parallel to a clubshaft and player's arms and
is gradually inclined backwardly from outside to its center and the upper half of
said circular face is bent forwardly to a center opening formed at the center of said
main frame, wherein on said circular face there are provided three loci indicating
clubhead arcs in backswing, downswing and follow-through respectively and are further
shown a plurality of straight lines indicating the clubshaft arc.
2. A practicing machine according to Claim 1, wherein said loci and straight lines
are shown on said circular face in such a manner that lower and upper points are firstly
marked on each of three vertical lines which are provided at the center of said main
frame and then an inner locus and an outer locus of backswing are drawn respectively
around said upper and lower points marked on the left side vertical line, an inner
locus and outer locus of downswing are drawn respectively around said upper and lower
points marked-on the center vertical line and an inner locus and outer locus of follow-through
are drawn respectively around said upper and lower points marked on said right side
vertical line and further said inner loci and outer loci are connected by a plurality
of straight lines which indicate the clubshaft arc.
3. A practicing machine according to Claim 1, further comprising a rim which is provided
on the circumferential -edge of said main frame and on the inside of said rim are
shown loci which indicate the open and close states of a clubface and connect with
said straight lines indicating the arc of a clubshaft.
4. A practicing machine according to Claim 1, further comprising a base plate wherein
said main frame is palced on said base plate are provided with shoulder pad and foot
pad which are respectively located front side and back side of said main frame.
5. A practicing machine according to Claim 1, further comprising a transparent flap
which is spacedly provided on the front side of said circular face to form a guide
goove wherein a clubshaft may be swung.
6. A practicing machine according to Claim 1, wherein said three loci indicating clubhead
arcs in backswing, downswing and follow-through and said straight lines indicating
clubshaft arc are made of rods which are connected to form a main frame.