In flour and bait factories, destoner is used for separating stone from grains. 

Grains fed through a vibrating inclined surface, in which vibration is formed by electric vibrating motors, are mechanically separated from stone thnaks to the density difference between grains and stone.

In order to visually monitor the process, sight glasses are fitted on the machine and an air connection is supplied for sucking foreign subtances lifghter than grains, and the dust occuring during the process.