Sports swing training device

Abstract
A sports swing training device comprising a grip, a shaft and a head used in practice of swing form of golf club or baseball or softball bat, wherein a hollow space is formed in the head and is partially filled with a liquid such as water or a solid material such as sand or small pellets.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a sports swing training device used for training in golf swing and/or baseball bat swing.




2. Description of the Related Art




U.S. Pat. No. 4,614,343 discloses a golf swing training device comprising a grip and a shaft constructed similarly to those parts of a real golf club, and a head made in a unique construction different from that of a real golf club. This training device has a metal bar called click finger provided in a locked state in the head, so that the click finger is unlocked so as to fall and make a click sound when the centrifugal force of a swinging motion is higher than a predetermined level.




With the golf swing training device disclosed in the U.S. Pat. No. 4,614,343, however, the click finger is unlocked and makes a click sound whenever the centrifugal force generated by the swinging motion of a golf club is higher than a predetermined level even in an unsatisfactory form, it is not effective in correcting the swing form.




U.S. Pat. No. 5,634,856 discloses a sports swing training method and apparatus that has a weight housed freely movably in a tubular body. This training apparatus is designed so that the weight moves and strikes a distal end of the tubular body when the head portion reaches an impact point on a ball in a satisfactory swing form.




The sports swing training apparatus disclosed in the U.S. Pat. No. 5,634,856 employs a bar-shaped weight, however, and there has been such a problem that the sports swing training apparatus cannot be made in a shape similar to a real golf club or a baseball bat.




SUMMARY OF THE INVENTION




The present invention aims at solving the drawbacks of the golf swing training devices of the prior art, and provides a swing training device that enables it to reliably and easily acquire a good swing form of not only golf club but also baseball or softball bat.




The present invention also aims at providing a sports swing training device that can be made in a shape substantially similar to that of a real golf club or a baseball bat.




In order to achieve the object described above, as a first feature, the invention provides a sports swing training device that has a grip, a shaft and a head and can be used in the practice of golf club swing or bat swing of baseball or softball, wherein the head has a hollow space therein with the hollow space being partially filled with a liquid such as water or a solid material such as sand or pellets.




According to the first feature, the user can master the proper swing form of golf club or baseball or softball bat, while listening to the sound generated by the liquid or pellets that partially fill the hollow space and checking the position where the sound is produced.




The user can also correct the swing form by checking the sound generated during the swing and the position where the sound is produced.




In addition to the first feature described above, the sports swing training device of the invention has such a second feature that the device is formed similarly to a golf club as a whole, wherein the head of the club has a hollow space therein with the hollow space being partially filled with a liquid such as water or a solid material such as sand or small pellets.




According to the second feature, the invention enables it, in addition to the operation and effect of the first feature, to correct one's golf swing form by checking the sound generated by the liquid or pellets that partially fill the hollow space generated during the swing and the position where the sound is produced, while operating the sports swing training device in a similar way to that of a real golf club.




Although the sports swing training device cannot be used in an official game, one can use the sports swing training device as a golf club when playing on a golf course and correct one's swing form.




When used as a golf club, the sports swing training device can also provide secondary impact due to the liquid or solid material contained in the hollow space, in addition to the impact generated by the face of the club head.




In addition to the first feature described above, the sports swing training device of the invention has such a third feature that the device is formed like a baseball or softball bat as a whole, wherein the head portion of the bat has a hollow space therein with the hollow space being partially filled with a liquid such as water or a solid material such as sand or small pellets.




According to the third feature, the invention enables it, in addition to the operation and effect of the first feature, to correct one's bat swing by checking the sound generated during the swing and the position where the sound is produced, while operating the sports swing training device in a similar way to that of a real baseball or softball bat.




Although the sports swing training device cannot be used in an official game, one can use the sports swing training device as a real bat when playing in a practice game and correct one's batting form. When used as a bat, the sports swing training device also provides secondary impact due to the liquid or solid material contained in the hollow space when hitting a ball.




As a fourth feature of the invention, the sports swing training device is formed in a cylindrical or ring shape as a whole so as accommodate a baseball bat or a golf club fitted detachably in the central hole, while the cylindrical or ring-shaped body has a hollow inner space hollow space therein with the hollow space being partially filled with a liquid such as water or a solid material such as sand or small pellets.




According to the forth feature of the invention, with the sports swing training device attached to a baseball bat or a golf club freely detachably, the user can master the proper swing form of golf club or baseball or softball bat, while listening to the sound generated during the swing motion and checking the position where the sound is produced.




As a fifth feature, the invention provides a sports swing training device that has a grip, a shaft and a head and can be used in the practice of golf club swing or bat swing of baseball or softball, wherein whistles that sound when air flows therein are provided in the grip and the head, so that the whistle provided in the grip is caused to sound by air flow generated therein when the grip is moved down swiftly in down swing, and the whistle provided in the head is caused to sound by air flow generated therein when the head moves swiftly.




According to the fifth feature, the user can master the proper swing form of golf club or baseball or softball bat, by checking to see whether the whistles installed in the grip and in the head make sound or not and whether the sound is proper or not. The user can also check his or her swing form by listening to the sounds of the two whistles during the swing motion.




As a sixth feature of the invention, in addition to the fifth feature described above, the sports swing training device has the whistles installed in the grip and in the head that make different sounds.




According to the sixth feature, in addition to the operation and effect of the fifth feature, the user can check to see whether his or her down swing form and the trajectory of the head before impact are good or not by listening to the different sounds.




As a seventh feature of the invention, the sports swing training device is formed in a cylindrical or ring shape as a whole so as to accommodate a baseball bat or a golf club fitted detachably in the central hole, while the cylindrical or ring-shaped body has whistle that sounds when air flows therethrough.




According to the seventh feature, with the sports swing training device attached to a baseball bat or a golf club freely detachably, the user can easily master the proper swing form of golf club or baseball or softball bat, while listening to the different sounds of the whistle.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

shows a first embodiment of the sports swing training device of the invention; FIG.


1


(A) in a perspective overview and FIG.


1


(B) in a sectional view of a key portion.





FIG. 2

shows a preferable trajectory of golf swing.





FIG. 3

explains a swing motion when the sports swing training device according to the first embodiment of the invention is used for training in golf swing.





FIG. 4

shows variations of the first embodiment of the invention, FIG.


4


(A), FIG.


4


(B) and FIG.


4


(C) showing partially cutaway views of key portions of the sports swing training devices.





FIG. 5

shows a second embodiment of the sports swing training device of the invention, FIG.


5


(A) showing an overview and FIG.


5


(B) showing a sectional view of a key portion.





FIG. 6

shows a third embodiment of the sports swing training device of the invention, FIG.


6


(A) showing an outside appearance and FIG.


6


(B) showing a sectional view.





FIG. 7

shows a variation of the third embodiment of the invention in an overview of the sports swing training device being attached to a golf club.





FIG. 8

is a detailed drawing of the sports swing training device shown in FIG.


7


.





FIG. 9

shows a fourth embodiment of the sports swing training device of the invention, FIG.


9


(A) showing an overview of a golf swing training device and FIG.


9


(B) showing an overview of a sports swing training device for baseball or softball.





FIG. 10

shows an outside appearance of a fifth embodiment of the sports swing training device of the invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




The first embodiment shown in

FIG. 1

will first be described below. Numeral


10


denotes a grip of the sports swing training device,


20


denotes a shaft and


30


denotes a head.




The head


30


has a hollow space


31


formed therein, with the hollow space


31


being partially filled with a content


32


comprising a solid material in the form of small pellets. The content


32


may be also a solid material such as sand or a liquid such as water.




The state of partial filling refers to the state of the content


32


filling the hollow space


31


not to the capacity thereof. Specifically, the content preferably occupies a half the capacity or a slightly smaller portion of the hollow space. This is because the spirit of the invention rests in that the head


30


work like the percussion instrument maraca through the combination of the hollow space


31


and the content


32


.




In the first embodiment, the grip


10


and the shaft


20


have shapes and dimensions similar to those of a real golf club, and the head


30


also has a shape similar to that of the head of a golf club, so that the sports swing training device is similar to a golf club in shape, dimensions, weight and balance.




It is not necessary to make the head


30


in the same shape as the head of a real golf club, and the head


30


may simply be the distal end of the shaft


20


being expanded or have other shape, as long as the head has the hollow space that contains the content.




Taking reference also to FIG.


2


and

FIG. 3

, operation of the sports swing training device used in training of golf swing will be described below. The motion of golf swing generally consists of a sequence of addressing (A), back swing (B), top swing (T), down swing (D), impact (I) and follow through (F).




The back swing (B) forms a relatively large arc, as the shoulder, arms and the club move in coordination.




During the down swing (D) that follows the top swing (T), it is said to be a good practice to pull down the shaft


20


while keeping the shaft in a vertical attitude as show in FIG.


3


. When moving from the down swing (D) to the impact (I), the grip


10


is returned to the position of addressing (A), so that the head


30


is turned rapidly to impart a strong impact to the golf ball.




Positions of the sports swing training device in a desirable swing form are shown in FIG.


3


.




In the path from the top swing (T) position to the down swing (D) position, the head


30


is directed vertically upward, and the shaft


20


is pulled down while keeping the shaft


20


in the vertical attitude, and therefore no centrifugal force is applied to the golf club till the down swing (D) position is reached. Thus during the desirable down swing motion, the content


32


provided in the hollow space


31


of the head


30


rests on the shaft


20


side due to the gravity that is predominant over the centrifugal force.




As the grip


10


is turned at a transitory position (E) between the down swing (D) and the impact (I), the head


30


moves swiftly resulting in a strong centrifugal force. Thus the content


32


moves quickly in the hollow space


31


from the shaft


20


side to the distal end so as to hit the inner surface on the distal end and make a sound. This action is similar to that of a maraca. That is, clear sound is produced only when the content


32


moves swiftly.




In case the user is a beginner incapable of swinging a golf club satisfactorily, he or she is likely to make a bad motion in the down swing (D) from the top swing (T) while keeping the shaft in vertical attitude, in a form called the hammer swing without keeping his or her arms tight on the body. In such a motion, the content


32


in the hollow space


31


of the head


30


begins, at the start of the swing, to move slowly due to the centrifugal force of the hammer swing that follows the top swing, until the content reaches the distal end of the hollow space


31


without making a clear sound. Thus the swing motion would be finished at the impact (I) without making a clear sound.




Therefore, the sports swing training device of the invention does not make a sound unless the sports swing training device is swung down in a correct motion of the down swing (D) from the top swing (T) to the impact (I) in a proper form.




Thus the user can acquire the proper swing form by correcting the motion until the sound is heard when the sports swing training device is swung down properly.




FIG.


4


(A), FIG.


4


(B) and FIG.


4


(C) show variations of the first embodiment of the invention, where the head


30


as well as the grip


10


and the shaft


20


of the sports swing training device are made in appearances not distinguishable from those of a real golf club.




FIG.


4


(A) shows the head


30


of the sports swing training device made similarly to the iron head of an ordinary golf club, while the hollow space


31


is formed in the head


30


, with the hollow space being partially filled with the content


32


so that the sports swing training device can be used for training in the swing of iron club.




FIG.


4


(B) shows the head


30


of the sports swing training device made similarly to the wood head of an ordinary driver club, while the hollow space


31


is formed in the head


30


, with the hollow space being partially filled with the content


32


so that the sports swing training device can be used for training in the swing of wood club.




In case the head


30


as well as the grip


10


and the shaft


20


are made similarly to those of a real golf club, as described above, swing motion can be practiced by using the sports swing training device just in the same way as a real golf club. Although the sports swing training device cannot be used in an official game, one can enjoy playing on a golf course using the sports swing training device. In this case, the sports swing training device may well be called a golf club. The present invention includes the sports swing training device that can be used as a golf club, in the scope of the invention.




In case the sports swing training device is used as a golf club when playing on a course, the impact of the head


30


generated when hitting a ball can be enhanced by the content


32


provided in the hollow space


31


. That is, when the head


30


hits the ball on the face thereof, the content


32


provided in the hollow space


31


hits the inner wall of the hollow space


31


on the face side by inertia, thereby imparting a secondary impact to the golf ball. This results in an increased flying distance of the golf ball.




The secondary impact can be increased by increasing the weight of the content, for example by using metal balls of higher specific gravity as the content


32


.




FIG.


4


(C) shows the head


30


of the sports swing training device made similarly to the wood head of an ordinary driver club similarly to FIG.


4


(B), except for the hollow space


31


in the head


30


located higher than in the case of FIG.


4


(B). By varying the vertical position of the hollow space


31


in this way, it is made possible to change the position of imparting the secondary impact to the golf ball when the content


32


hits the inner wall of the hollow space


31


. Thus the take-off angle of the golf ball can be adjusted.





FIG. 5

shows the second embodiment of the sports swing training device of the invention. The sports swing training device according to this embodiment comprises a grip


100


similar to the grip of a bat, a shaft


200


similar to the middle portion of a bat and a head


300


similar to the head portion of a bat, in a constitution similar to that of a baseball or softball bat as a whole.




The head


300


has a hollow space


310


formed therein, with the hollow space


310


being partially filled with a content


320


comprising small pellets. The content


320


may be either a solid material such as sand or a liquid such as water.




Swing motion of a bat has a common factor with the golf swing, and it is said that good practice is to pull down the bat (shaft


200


) from the top position (waiting position of the bat ready for swing) while being directed vertically upward, followed by turning of the grip so as to move the head


300


, thereby imparting a strong impact to the ball.




Thus during the desirable down swing motion and the turning of the grip, the head


300


of the bat moves swiftly resulting in a strong centrifugal force at a transitory position between the down swing and the impact. At this time, the content


320


moves swiftly from the shaft


200


side to the distal end in the hollow space


310


, and hits the inner wall at the distal end so as to make sound.




In the case of a swing form called the hammer swing carried out without with keeping his or her arms tight on the body, the content


320


moves slowly within the hollow space


310


from the start of swing toward the distal end, without with making a clear sound when the impact position is reached.




Thus the user can acquire the proper form of bat swing by correcting the motion until a clear sound is heard when the impact position is reached.




The training device for bat swing may also have a slender grip and a slender shaft similar to those of a golf club, although the head must be concentric with the shaft at the distal end of the shaft. The head must not be eccentrically connected with the shaft as in a golf club.




FIG.


6


(A) and FIG.


6


(B) show the third embodiment of the sports swing training device of the invention. This embodiment provides a simplified sports swing training device, that is fitted detachably on a bat for use in a waiting circle or other places for the purpose of training in bat swing.




The sports swing training device is formed in a cylindrical or ring shape as a whole and the body


40


has a central hole


43


that accommodates a bat near the head portion


300


of the bat, with a hollow space


41


formed in the body


40


. The hollow space


41


is partially filled with a liquid such as water. The content


42


may also be a solid material such as sand or small pellets. The body


40


may have a capped charging port


44


through which the hollow space


41


can be filled with the content


42


or emptied. The charging port


44


enables it to fill the hollow space


41


with the content


42


such as water when necessary, and empty the content


42


when unnecessary. Weight of the bat can also be changed by adjusting the quantity of the content


42


.




When the simplified sports swing training device of this embodiment is fitted near the head


300


of a bat and used in the practice of bat swing, a sound is generated at the position of impact in a good swing, similarly to the case of the second embodiment described in conjunction with FIG.


5


. Thus the user can correct his or her swing form into a proper form, and verify the swing form.




FIG.


7


and

FIG. 8

show variations of the simplified sports swing training device according to the third embodiment of the invention described in conjunction with FIG.


6


. This embodiment is a simplified sports swing training device that can be attached on a golf club, at the distal end of the shaft


20


near the base of the head


20


as shown in

FIG. 7

, and used for training in golf swing.




Similarly to that shown in

FIG. 6

, the body


40


formed in cylindrical or ring shape has a hollow space, that is not shown, with the hollow space being partially filled with a liquid such as water not shown, and the central hole


43


to accommodate a golf club.




The body


40


has clamp pieces


44


and clamp rings


45


shown in

FIG. 8

, for example, as means for fastening the body on the shaft


20


of the golf club. The clamp pieces


44


are provided in plurality (four in the drawing) in such a constitution as can be moved in the radial direction (X direction) toward and away from the shaft


20


that is fitted in the central hole


43


. Clamping effect can be made more reliable by making the bearing portions


44




a


of the clamp pieces


44


, that contact with the shaft


20


, from rubber. Numeral


46


denotes stoppers for the clamp pieces


44


.




With the clamp pieces


44


being pressed against the shaft


20


from around, the clamp rings


45


are moved in the axial direction (Y direction) thereby to fasten the clamp pieces


44


on the body


40


.




The means for fastening the body


40


on the shaft


20


is not limited to the clamp pieces


44


and the clamp rings


45


.




Such a constitution may also be employed as hollow space (


31


,


310


) and content (


32


,


320


) are provided also in the grip (


10


,


100


) as well as in the head (


30


,


300


). This constitution makes such an effect as a sound is made by the content (


32


,


320


) hitting in the grip (


10


,


100


) during the down swing and another sound is generated by the content (


32


,


320


) in the head (


30


,


300


) near the impact point, when the golf club or bat is swung in a proper form.





FIG. 9

shows a fourth embodiment of the sports swing training device of the invention, (A) showing the sports swing training device furnished as a sports swing training device for golf, comprising a main body made in the shape of a golf club as a whole that has a grip


10


, a shaft


20


and a head


30


, wherein whistles


51


,


52


are provided in the grip


10


and the head


30


. FIG.


9


(B) shows the sports swing training device furnished as a bat swing training device for baseball or softball, comprising a main body made in the shape of a bat as a whole that has a grip


100


, a shaft


200


and a head


300


, wherein whistles


51


,


52


are provided in the grip


100


and in the head


300


.




The whistles


51


,


52


are made so as to sound when air flows therethrough. The whistles


51


,


52


can be provided in the grip


10


and the head


30


, and in the grip


100


and the head


300


, respectively.




When the sports swing training device having the shape of golf club or baseball bat having the whistle


51


provided in the grip


10


,


100


is swung, a sound is generated by air introduced through the end of grip


10




a


,


10




a


and flowing through the whistle


51


, as the grip


10


,


100


is moved swiftly downward with the end of the grip


10




a


,


100




a


directed downward. For example, such a constitution may be employed as an aperture


61




a


is formed in the grip


10




a


,


100




a


so as to form an air passage


61


in the grip


10


,


100


, while the whistle


51


is installed amid the air passage, so that the air that has passed through the whistle


51


flows through the aperture


61




b


to the outside. The whistle


51


is adjusted in advance so as to make sound only when the grip


10


,


100


is moved swiftly downward with the end of the grip


10




a


,


100




a


directed downward.




When the sports swing training device having the shape of golf club or baseball bat having the whistle


52


provided in the head


30


,


300


is swung, a sound is generated by air flow generated as the head


30


,


300


is moved swiftly.




In the case of the sports swing training device having the shape of golf club, such a constitution may be employed as apertures


62




a


,


62




b


are formed in the head


30


so as to form an air passage


62


that penetrates the head in the direction of swing, while a whistle


52


is installed in the air passage


62


. The whistle


52


may also be fixed on the outside of the head


30


so as to allow the air to pass in the direction of swing.




In the case of the sports swing training device having the shape of baseball bat, such a constitution may be employed as the aperture


62




a


is formed in the side face of the head


300


so as to form the air passage


62


in the head


300


, while the whistle


52


is installed in the air passage


62


. The air that has passed through the whistle


52


is caused to flow out of the bat through another side face


62




b


of the head


300


or the distal end of the head


300


. The aperture


62




a


provided on the side face of the head


300


may also be provided in plurality around the head


300


as air inlet holes. The whistle


52


attached on the head


300


of the bat may be provided in plurality around the head


300


so that the bat can be held at any angular position around the axis.




With the whistles


51


,


52


provided in the grip


10


,


100


and the head


30


,


300


as described above, the whistle


51


sounds as proper air flow passes through the whistle


51


when proper down swing is made. When the head


30


,


300


is moved swiftly following the proper down swing, the whistle


52


sounds due to air flow therethrough. The whistle


51


does not sound when the down swing is not made properly. The whistle


52


does not sound also when the head


30


,


300


is not moved swiftly.




The sound of the whistle


51


provided in the grip


10


,


100


and the sound of the whistle


52


provided in the head


30


,


300


may be made different from each other, such as sounds of different tones. With the different sounds, wrong portion of the swing form can be identified.





FIG. 10

shows a fifth embodiment of the sports swing training device of the invention. This embodiment provides a simplified sports swing training device similar to that described in conjunction with

FIG. 6

, that is fitted detachably on a baseball bat for use in a waiting circle or other places for the purpose of training in bat swing.




The sports swing training device of this embodiment comprises a body


40


that is formed in a cylindrical or ring shape as a whole and has a central hole


43


that accommodates a bat near the head portion


300


of the bat fitted therein, while a whistle


53


is provided in the body


40


. By providing apertures


63




a


,


63




b


in the body


40


, one or more air passage


63


is formed so as to penetrate the body


40


horizontally, with the whistle


53


being installed in the air passage


63


. One or more whistle


53


may also be attached on the outside of the head


40


, so that air passes through the whistle


53


horizontally.




When the simplified sports swing training device constituted as described above attached to a bat is used in practicing bat swing, an effect similar to that of the fixed whistle


52


shown in FIG.


9


(B) can be expected from the whistle


53


of this simplified sports swing training device.




It needs not to say that the simplified sports swing training device shown in

FIG. 10

can also be used while being attached to the grip


100


of the bat, by varying the dimensions and shape. In this case, such a constitution may be employed as the body


40


is made in a shape that allows it to be freely detachably attached to the grip


100


, and the whistle


53


is attached to the body


40


so that the air flows through the whistle in the axial direction of the grip


100


(so as to operate similarly to the whistle


51


shown in FIG.


9


(B)).




The simplified sports swing training device may also be adapted for golf club. In this case, such a constitution may be employed as the shape of the body


40


shown in

FIG. 10

is changed to a shape and mechanism that allow it to be freely detachably attached near the head


30


of a golf club, and the whistle


53


is attached to the body


40


so that the air flows through the whistle in the direction of golf swing (so as to operate similarly to the whistle


52


shown in FIG.


9


(A)). When the sports swing training device is used while being attached to the grip


10


of a golf club, such a constitution may be employed as the body


40


is made in a shape and mechanism that allow it to be freely detachably attached to the grip


10


of the golf club, and the whistle


53


is attached to the body


40


so that the air flows through the whistle in the axial direction of the grip


10


(so as to operate similarly to the whistle


51


shown in FIG.


9


(A)).



Claims
  • 1. A sports swing training device formed in a cylindrical shape with a central hole to accommodate a baseball bat or a golf club, said central hole being suitable for detachably engaging the shaft portion of an associated baseball bat or golf club wherein the cylindrical-shaped body is self-supporting and has a hollow space formed therein that is partially filled with a liquid or a solid material, whereby a distinct sound is generated at a position of impact when said material moves quickly in the hollow space from a proximal end to a distal end and hits an inner surface on the distal end and thereby achieves audible support for operation of the swing training device.
  • 2. A sports swing training device suitable for use with a baseball bat or a golf club, said device comprises;a cylindrical or ring shaped body with a central hole, said central hole being suitable for detachably engaging the shaft portion of an associated baseball bat or golf club, said cylindrical or ring shaped body includes a hollowed out internal enclosure, said enclosure being suitable for retaining a liquid, or alternatively, a solid material, said device further comprises plural clamp pieces, with each of said clamp pieces contoured to matingly contact an external segment of said body as well as a portion of the shaft of an associated baseball bat or golf club, said clamp pieces include means for controlled radial movement along the cylindrical or ring shaped body and thereby provides a clamping effect to insure integral contact between the sports swing training device and an associated baseball bat or golf club.
  • 3. A sports training device according to claim 2, wherein the cylindrical or ring shaped body further comprises at least one distinct clamping ring adapted for controlled axial rotation and thereby provide an added clamping effect between the sports swing training device and an associated baseball bat or glove.
Priority Claims (1)
Number Date Country Kind
2001-232330 Jul 2001 JP
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4029312 Wright Jun 1977 A
4260150 Tabet Apr 1981 A
4330121 McCafferty May 1982 A
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