| 摘要 |
<p>The device according to the invention comprises a frame (1) whose upper part of the framework (4) supports a net (2) which comprises means for forming a pocket (2d) whose lower part is weighted by a ring (8) surrounding its opening (2c). The frame (1) carries a vertical pivot (14) on which is placed the base of the casing of the launcher (3) which is, additionally, attached to the said frame by a flexible link (15, 16). Thus, the impact of the balls on the net (2) causes vibrations of the frame (1) which give rise to variations in the position of the launcher (3) which are, additionally, caused by the ejection of the balls, so that their trajectories are random. <IMAGE></p> |
