| 摘要 |
<p>The ball holder for volley ball smash training is on a holder plate which can be fitted to gymnasium horizontal bar posts by means of a screw which passes through a hole in the holder plate and a hole in the post. Each frame has two arms of metal tubing into which are fitted elastic plastic rods on whose ends are pieces of soft rubber. The tubes are adjusted to an angle of 87 deg. by an adjuster screw so that a ball placed at the beginning of the frame, automatically runs down tot he end to be held between the two frames on the soft rubber pieces. The plastic rods and rubber end pieces ensure that when the ball is struck the user cannot be injured. The framework is light and easily installed to any requied height and because of its simple construction can be made very cheaply.</p> |
