Abstract: The article illustrates the importance of improving the precision of splitwhich is important for Coal mechanical sampling, analysis the research status at home and abroad, proposed a new type of split device. A study of relationship between split precision and the structure or the position of inletvia the coal falling has been done.This study has been used for designing the new type of split device.At the same time, analysis the current problems in split device and put forward the concrete solution, improved the split precision of the split device to a new level, and make a powerful guarantee for mechanical sampling system.

Key words: Coal mechanical sampling, Split device, Precision of split, Precision