| 摘要 |
<p>The tennis trainer ball ejection alignment device is also suitable for other similar trainers. Balls are ejected through an open topped frame driven by electronically controlled friction drive motors. The face (1) of the machine carries a tabular representation of the court (2) or half of it, so that the desired target point (14) for the ball can be coordinated using side line indicator strips (6,7). The electronic control is programmed to eject balls to the desired target point, and with the desired spin characteristic, according to the settings on the face (1) of the machine. A manual scale (8) associated with the side line (6) adjusts the friction drive wheels etc. in the ejection frame. Indicators (6,7) are LED types. Adjustment knobs (9,10) for motor controls associated with the line scales (6,7) are provided as are spin control adjustment knobs (17,18) with scales (19,20).</p> |
