Abstract:
A standard-camera-tripod-mountable tennis (or other sport) training device is disclosed. A section of 3″ PVC is cut lengthwise into a half-pipe (chute) and attached to a mounting block that allows for attachment to a standard camera tripod via a 1/4″-20 nut in the base of the mounting block. The device allows for consistent, precise delivery of a slow moving tennis ball or other projectile, thus facilitating training.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not applicable. 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable. 
       REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX 
       [0003]    Not applicable. 
       BACKGROUND OF THE INVENTION 
       [0004]    This invention will help tennis players (or other sport players that need to strike a ball) learn to hit the ball well. As a good amateur tennis player and a lover of the game, I&#39;ve seen many amateurs struggle to hit the ball well. Most players have poor footwork, poor preparation and they frequently hit the ball “late”. Instead of assertively striding into the ball and catching it early, they wait a fraction of a second too late . . . and then awkwardly compensate, fighting to get the ball back. So the players adopt different styles of compensating and learn to get the ball back one way or another. So they practice and hone fundamentally flawed strokes, some even playing really well, but their games are limited in growth potential because they don&#39;t know how to step into the ball and hit it early. 
         [0005]    This lack of footwork and timing robs the player of power. When a well-coached tennis player “steps into the ball”, power is derived from a kinetic chain that starts with the back foot. Imagine a baseball pitcher on a mound, striding toward homeplate, his back foot pushing off from the pitching rubber. Without the additional thrust from his back foot, the pitcher would be an extremely weak pitcher. Or consider the classic image of a batter who&#39;s just jacked a homer and then visualize his back foot, where he&#39;s firmly stepped into the ball. The batter would be an extremely weak batter if he didn&#39;t step into the hit. But so it is with many tennis players. Instead of a stroke that involves the whole body, many tennis players simply swing their arms, pivoting at their shoulder, without stepping into the ball, which forces them to compensate by swinging faster. Faster swings have less margin of error, and thus more errors occur. Fast swings also contribute to ‘tennis elbow’ or other stress disorders of the shoulder, arm and hand. If tennis players could be taught how to step into the ball, they wouldn&#39;t have to swing as hard. They would get much of the power needed to return the ball from their legs and hips, thus they could swing slower and have more precise strokes. 
         [0006]    Hitting the ball late also makes it hard to hit with topspin. If a player can learn to step into the ball and hit it early, a natural topspin stroke can evolve easily. When a player is stepping into the ball and catching it early, the contact point is out in front of them. Because the racket arm functions much like a pendulum, if you&#39;re hitting the ball early, the racket head will be naturally pulled up near the point of contact, thus creating topspin. 
         [0007]    Ball machine prior art: Most commercially successful tennis ball machines shoot the ball at the player. For example consider patent U.S. Pat. No. 4,841,945 by a great tennis mind, Vic Braden. But with these ‘shooter’ ball machines, there are lots of players out there practicing hitting the ball late. 
         [0008]    As I reflected on the problem, I felt there was a need for a device that would drop the ball consistently in the same spot, so the aspiring tennis player would know precisely where the ball was going to be and learn to adjust to that. After ruminating on this problem for a number of years, I conceived a simple, elegant solution. 
         [0009]    A search of prior art found multiple machines that are ‘droppers’ (i.e., they drop a tennis ball so it bounces to the same spot predictably). But invariably, these machines are complex solutions to a simple problem. U.S. Pat. No. 6,283,876 is a ball dropper that has “no horizontal velocity”. U.S. Pat. No. 4,021,036 is another ball dropper with a hopper and a “ball projection mechanism” at the end of a “hollow extension arm”. U.S. patent Ser. No. 11/557,470 is another ball dropper with a hopper. The complexity of these machines adds cost and weight, which might explain their lack of market penetration. (I&#39;d never seen these on the market before the search for prior art.) 
       BRIEF SUMMARY OF THE INVENTION 
       [0010]    In this invention, a roughly 2′ section of 3″ PVC pipe is cut lengthwise into a halfpipe or chute. The chute is screwed atop a wood mounting block. The block has a countersunk ¼″-20 nut centered at the bottom to allow for mounting on a standard camera tripod. The tennis student mounts the TennisChute on the tripod, adjusts the ‘tilt’ on the tripod such that there is a slight incline, orients the chute to drop the ball “sideways” and then is ready to practice. The learning player drops the ball into the high end of the chute, then ‘tracks the ball’ (practicing footwork) as it rolls down the incline and then adjusts to the ball and then hits the ball once it drops and bounces. 
         [0011]    Advantages: 
         [0012]    Since the ball drops to the same spot every time, a coach can watch the player and provide direction on how to better adjust to the ball and refine stroke mechanics under controlled conditions; so unlike a ‘shooter’ ball machine, the ball cannot ‘get behind’ the player. The TennisChute has an advantage over previous ball ‘droppers’ in that it is very lightweight, simpler and thus more affordable and portable. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0013]    A single drawing is included that shows a chute  1  (a roughly 2′ section of 3″ PVC cut lengthwise into a halfpipe). Chute  1  is screwed into a mounting block  2  (a roughly 4″ by 2″ by 1″ chunk of wood). Centered and countersunk on the bottom of the mounting block is a serrated flange ¼″-20 nut  3 , suitable for mounting the TennisChute on a standard camera tripod. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0014]    In order to make the invention, first cut some 3″ PVC (or other strong and light cylindrical material) to a roughly 2′ to 3′ length, then cut it in half lengthwise to create a chute  1 . To make a mounting block  2 , cut a chunk of wood or similar material into a small block approximately 1″ thick and 4″ long and 2″ wide. Bore a ⅝″ hole to a depth of 0.3″ in the center of the bottom of the mounting block, to allow for the countersinking of the ¼″-20 serrated flange nut  3 . Nut  3  should then be glued or otherwise permanently affixed into the countersink hole. Then chute  1  can be screwed into the mounting block  2  using crossdrive flathead screws so that when countersunk, their presence won&#39;t disturb the path of a ball rolling down the chute. 
         [0015]    In order to use the invention, the player should mount the TennisChute on a standard camera tripod and then set the tilt on the tripod to create a slight incline of the chute. It is suggested that until the player knows how to ‘step into the ball’ properly, that the chute be initially oriented “sideways”. Normally in tennis, the ball is hit back and forth. Because the ball is normally traveling toward the player, if the player waits too late, they miss the chance to step into the ball. If the ball is traveling sideways, the ball cannot get behind them. The player can be coached to set their back foot at an appropriate depth (say 3′ behind and 3′ to the side of the contact point, depending on the player&#39;s height). With the back foot set deep, the player has to ‘step in’ to hit. 
         [0016]    The player needs to be taught the best grip to use for hitting the ball in front of them. An “eastern forehand” and an “eastern backhand” grip are good for hitting the ball in front of them and stepping into the ball. Many players use a “continental” or “hammer” grip. This grip is not suitable for hitting the ball early. The angle of the racket face virtually forces you to hit the ball late if you use the hammer grip. If you hit the ball early with a “hammer” grip, the racket face will be too open and the ball will most likely fly high and long. 
         [0017]    Using the TennisChute, it is fairly simple to teach a fundamentally sound topspin stroke, where the whole body is involved in the stroke. The player gains power from good footwork. By catching the ball early, a natural topspin evolves because at the end of the stroke, the player&#39;s arm is pulled up. This topspin allows the player to hit the ball harder and the aerodynamics push the ball down to keep it in the court, a la Rafael Nadal. With the power from good footwork, the player also gains control because the player can swing slower and still hit the ball solidly. A slower swing speed translates to more consistent results. Once a player has developed consistency and control at a slow speed, racket speed can then be added. 
         [0018]    The advantages of the invention include a simple design, low cost and a very low weight and thus portability. The player merely carries a standard tripod and the TennisChute to the court and in minutes, the player can be working on footwork and form for an extremely low cost. Also, since the ball is moving at the slowest possible pace, the challenge of learning to hit well is made as simple as possible. Another advantage is that the TennisChute can be used to practice half-volleys (where the player hits the ball immediately after it bounces). The coach can instruct the player to stand near the bounce point and then precisely feed balls and instruct the player how to ‘pick the ball up’ from the bounce. 
         [0019]    Alternative Embodiments: 
         [0020]    The invention could be made with a different diameter chute in order to accommodate different size sports balls. The chute could also be permanently affixed to a tripod that had a tiltable and pannable head instead of using a standard camera tripod.