Abstract:
A device for practicing an address stance and ball-hitting motion in a sport such as softball. A batter stands on a step plate ( 30 ) and a swivel plate ( 31 ) mounted on a flat base ( 12 ). The plates have adjustable separation, and align the user&#39;s feet using toe stops ( 36 ). The step plate ( 30 ) has foot guards ( 34 ) that force the user to step towards the pitch. The swivel plate ( 31 ) rotates about a vertical axis, and has foot-retaining straps ( 38, 39 ) that allow the heel to lift. Swivel stops ( 18, 20 ) limit the rotation range between address alignment and a safe maximum swivel. The user learns to step toward the pitch and swivel the back foot while swinging the bat, turning the body, and shifting weight toward the pitch. The foot plates ( 30, 31 ) are reversible on the base ( 12 ) for right or left-handed use.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of U.S. provisional application 60/671608, filed Apr. 15, 2005 and U.S. provisional application 60/679,616, filed May 10, 2005 

   FIELD OF THE INVENTION  
   This invention relates to the field of training aids for batting a ball, and especially to devices for training the foot positions and body movements for batting a ball such as a baseball or softball. 
   BACKGROUND OF THE INVENTION  
   Numerous bat swing training aids have been devised for softball and baseball. Some of these include plates or mats placed on the ground beside a home plate, with foot placement indications for an address stance and swing stride. These aids vary in emphasis, mode of enforcement, intended result, safety, and other factors. However, none of them combines an ideal training result with safety, convenience, and practicality in the same way and to the same degree as the present invention. 
   For example, a product called “stride guide” is a flat plate with foot placement and stride indicators and a rotating disk for the ball of the back foot. It has a raised edge behind the disk to enforce lifting of the back heel, thus shifting the user&#39;s weight forward. It has other raised edges to limit the stride of the lead foot. However, it does not require the user to step with the lead foot, rather than slide, it does not physically set both feet in toe alignment for the address stance, it does not physically align the lead foot perpendicularly to the pitch, it does not physically set the address stance width, it does not retain the back foot, and it does not limit the pivot range of the back foot. 
   The present inventor feels that physical enforcement of address stance and stepping into the swing provides more definitive training and faster coaching than visual indicators alone, and that these physical enforcements make a stronger impression on a user&#39;s “muscle memory”. She also feels that physical limits on the back foot pivot range are important, both for training and safety. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is explained in following description in view of the drawings that show: 
       FIG. 1  is a perspective view of an embodiment of the invention 
       FIG. 2  is a perspective view of a ground anchor 
       FIG. 3  is a top view of the embodiment of  FIG. 1 . 
       FIG. 4  is a side view of the embodiment of  FIG. 1 . 
       FIG. 5  is a sectional view taken along section line  5 — 5  of  FIG. 3 . 
       FIG. 6  is a sectional view taken along section line  6 — 6  of  FIG. 3 . 
       FIG. 7  is a top view of left and right-handed configurations of the device relative to a home plate, with an extended lead portion of base. 
   

   DETAILED DESCRIPTION OF THE INVENTION  
   The inventor recognized that a better training aid would be useful in instructing softball and baseball users during batting practice to align their feet in the address stance, to avoid putting their feet too far apart, to lift the back heel, and to step toward the pitcher and shift their weight while swinging the bat. She devised a convenient and practical device for this purpose. In this description “front” or “forward” means toward the ball pitcher, “back” means away from the ball pitcher. Gender-specific pronouns are used for convenience only, and are intended to include both genders. 
   The drawings illustrate an embodiment of a device for training the foot positions and body motions for batting a ball such as a baseball during the address stance, swing, and follow-through. It teaches proper foot orientation and stance width, swing stride, shifting of body weight, and proper back foot pivot. It comprises a base plate  12  with anchor holes  14  for ground anchors  15 . A step plate  30  for the lead foot comprises a traction surface  32 , a raised toe stop  36 , and two raised foot guards  34 . The step plate  30  is mounted to the base plate  12  at a selectable position provided by pegs  17  in alternate peg holes  16  as seen in  FIG. 5 . A swivel plate  31  for the back foot comprises a traction surface  32 , a raised toe stop  36 , and foot restraint straps  38 ,  39  arranged to hold the ball on the foot on the plate while allowing the heel to lift. The swivel plate  31  is mounted on the base plate  12  by a bearing  42  that allows rotation of the swivel plate  31  about a vertical axis. The bearing  42  may be recessed in the base plate  12  as in  FIG. 6  so that the top surfaces of the step plate  30  and the swivel plate  31  are at approximately the same height. As an example of bearing  42  a ring of ball bearings captured between two race plates can be used. The base plate  12  may be divided in half along a hinge line  28  connected by a hinge  26  for compact folding. It may further comprise a handle  29  on each half for convenient carrying of the folded device. The handles  29  may be on the ends of the base plate  12 , as shown, or on other parts of the edge. 
     FIGS. 1 and 3  show a swiveled position  44  of the swivel plate  31  that occurs during a batter&#39;s swing. The swivel range is limited by swivel stops  18 ,  20 ,  22 ,  24  in the base plate. This prevents excess swiveling that overshoots the desired running position and could injure a user&#39;s ankle or knee. Two stop pegs  19  are inserted in a selected two of the stop holes  18 ,  20 ,  22 ,  24  depending on right or left-handed use. For a right-handed batter, swivel stop holes  18  and  20  are pegged. The peg in hole  18  stops the swivel plate  31  in alignment with the step plate  30  for the address stance. The peg in hole  20  stops the swivel during the swing. Swivel stop  20  provides a predetermined swivel angle such as 40 degrees. Optionally, a series of stop holes  20  (not shown) or another adjustable stop means (not shown) can be provided so the user can select a swivel angle within a range such as 20–90 degrees, for both hitting and bunting practice. 
   The step plate  30  is adjustably mounted so users know where and how to begin their address stance. This prevents them from starting with their feet too far apart. A series of stance width adjustment holes  16  may be provided on the base plate  12 . The step plate  30  may have a bottom surface with mounting pegs  17  extending downward for insertion into selected adjustment holes  16  as in  FIG. 5 . This allows the step plate  30  to be mounted on the base plate in a position that provides a natural stance for the user, such as approximately shoulder width apart from the swivel plate  31 . 
   The length of the baseplate(s) may be any selected length, with both halves being of equal or of unequal length as measured from the hinges.  FIG. 7  shows a version of this device with a base  12  with one half that is larger in the forward direction. This extension provides extra space upon which the lead foot can step during the swing, as shown by footprints  46 . The base may be asymmetric about the hinge  28 , as shown in  FIG. 7 . Two handles  29  can be provided as shown that are equidistant from the hinge-line  28  at approximately a balance point when the base is folded. This brings the handles together in the folded position of the base for easy carrying, so that a latch is not needed to maintain the folded position.  FIG. 7  shows a right-handed configuration  48  and left-handed configuration  50  of the device relative to a home plate  52 . 
   To use this device a user puts her back foot, which is the foot furthest from the pitcher into the swivel plate  31  up to the toe stop  36 . Then she adjusts the toe strap  38  across the foot, and adjusts the ankle strap  39  over the foot and around the ankle. This retains the foot on the swivel plate  31  while allowing the heel to rise during the swing. The user puts her lead foot on the step plate  30  with her toe against the toe stop  36  and the leading side of the foot against a foot guard  34 . The user is now standing on the two plates with her feet aligned with each other as shown by footprints  46  of  FIG. 7 . 
   The user takes an address stance for swinging a bat at a pitched ball. The user steps forward towards the pitch, shifts body weight toward the pitch, lifts the back heel, and twists hips and shoulders toward the pitch, causing the swivel plate  31  to turn to its stop. Proper foot alignment is taught by placing one foot on the stepping plate  30  and one foot on the swivel plate  31 . The user places each foot forward to the respective toe stop  36 . This teaches the user to align the feet evenly. The front foot is placed against the forward-most foot guard so the foot is perpendicular to the pitch. The user&#39;s back foot is strapped on to the swivel plate with a toe strap across the toe area and an ankle strap around the ankle. The proper address stance width is important so the user does not overstep the swing. Stance width is set by adjusting the stepping plate  31  to the natural stance of the user by mounting the stepping plate pegs  17  in a selected pair of holes  16 . 
   Once the user has proper placement of her feet on the stepping plate  30  and the swivel plate  31 , she is ready to begin her swing. The user will step over the foot guard  34  on the stepping plate  30 , causing her weight to shift forward toward the ball. This will happen naturally when she steps, since the base plate  12  is lower than the stepping plate. It is important for the user to learn to step forward and not to slide the front foot forward, in order to ensure proper weight shift to the front leg. The foot guard  34  requires the user to lift the front foot a predetermined distance to clear the foot guard  34 , thus training the user not to slide the foot. The base can be made long enough to receive the lead foot after it steps forward off of the stepping plate. The user&#39;s back foot stays against the toe stop  36 . The heel of the back foot is raised, shifting weight to the ball of the foot as the user turns the foot and the swivel plate  31 . 
   This device is designed for practical manufacture. All plates  12 ,  30 , and  31  can be fabricated from standard flat stock material using conventional machine tools or woodworking tools and methods, or they can be molded or otherwise formed. The step plate  30  and the swivel plate  31  can be formed in the same mold, including foot guards  34  on both plates, to reduce tooling cost. The materials for the construction of the various structural members of the device may be plastic, wood, metal, fiberglass, or other material having the required strength and preferably lightweight for easy portability. The peg holes  16 ,  18 ,  20 ,  22 ,  24  in the base plate may be lined with sleeves (not shown) to enable the pegs to be removed and replaced repeatedly without damaging the base plate  12 . 
   Holders for the anchors  15  may be provided on the base plate  12 . For example, depressions  13  can be provided in the base  12  as shown in  FIGS. 1 ,  3 , and  4  to frictionally grip and hold the anchors in a stored position. Spring clips or other known holders can also be used. The anchors may have loops  41  as shown in  FIG. 2  for easy manual pulling of the anchors from the ground. In this case, the anchors can be stored on the toe strap  38 , without need for other holders. 
   The step plate  30  has two lateral adjustment pegs  17  on the bottom, a non-skid upper surface  32 , a toe stop  36 , and a raised foot guard  34  on each side. One foot guard  34  is used for right-handed hitters and the other is used for left-handed hitters. To convert between right and left-handed hitters the step plate  30  is lifted from the base  12 , rotated 180 degrees, and reset in the adjustment holes  16 . 
   The swivel plate  31  has a toe stop  31  with holes  40  for attaching the ankle strap  39 . The toe strap  38  can be attached to the swivel plate as shown. Optionally two foot guards  34  can be provided on the swivel plate  31  as on the step plate  30  to prevent the back foot from slipping off the swivel plate  31 . In this case, the toe strap  38  can be attached to the foot guards. To convert the swivel plate  31  between right-handed and left-handed hitters, the stop pegs  19  are removed, and the swivel plate is rotated 180 degrees, then the stop pegs  19  are placed into stop holes  18  and  20  for right-handed hitters or holes  22  and  24  for left-hand hitters. Optionally, the stop pegs  19  may be provided in the form of captured spring-loaded buttons in all of the stop holes  18 ,  20 ,  22 ,  24 , that toggle between an extended and retracted position. 
   The toe and ankle straps  38 ,  39  may be made of leather, fabric, plastic, or other appropriate material. The two ends of each strap should have the capability of being joined together and loosened to facilitate insertion and removal of the foot. The clasp for the straps may be a buckle, VELCRO brand fastener, cinch strap with ring, quick release buckle or simply a tie or some other appropriate clasp. The ankle strap  39  may or may not be crossed over the top of the foot. 
   While various embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes and substitutions may be made without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims.