POSITIVE-DISPLACEMENT PUMP Russian patent published in 1994 - IPC

FIELD: handling viscous media with solids. SUBSTANCE: mounted in housing is hollow floating piston connected on either side with bellows whose other sides are secured on housing covers forming working chambers. Housing is made in form of thin-walled sleeve. Formed between this sleeve and bellows are closed chambers which are brought in communication with drive medium source. Gloating rings located in the chambers are secured to projecting parts of bellows. Cylindrical diaphragm made of elastic material is fitted in hollow piston whose lateral surface is provided with holes. Rings have slots for feeding the drive medium to the piston interior through the holes in it. EFFECT: enhanced efficiency. 4 dwg