作者: Richard A. Krzysztofiak , George Kalucik
DOI:
关键词:
摘要: A table tennis trainer having a net trap erected for positioning at one end of and associated therewith ball collecting return assembly tube with negative pressure gradients to move the supply box where balls are delivered by gravity into feed mechanism which selectively delivers delivery positive propel said onto surface towards practicing player. valve is provided control gradients, vary propelled force balls, an oscillating swing from side selected speed controlled remotely