BLOWING AND SUCTION DEVICE, MORE SPECIFICALLY A VACUUM DEVICE FOR PICKING UP AND SHREDDING LEAVES AND SIMILAR MATERIAL

摘要

The blowing and suction device of the present inventionis especially designed for vacuum choppers used for picking upand shredding leaves, grass, refuse, and similar material.The device consists of a blower casing and a impeller insidereceiving a rotary motion from a drive unit for sucking in airthrough an intake opening in the blower casing and forexpelling the air through an exhaust opening in the blowercasing. The impeller has a circular bottom plate with acentrally positioned bearing for the drive shaft; on the sideof the bearing facing away from the drive shaft there arevertically projecting fan blades which extend radially fromthe centre outwards to the edge of the bottom plate in thepattern of a tangential fan. Two or more, but at the mostevery second one, of the fan blades carry on their surfacefacing away from the bottom plate a chopping blade projectingin the direction of the air suction. The advantage obtainedby the invention is essentially that the chopping bladespre-shred the material sucked in, the distance between them beingsufficient to prevent clogging. Only the pre-shreddedmaterial arrives in the vicinity of the fan blades, wherefurther shredding of the material then takes place. As aresult, no pieces arrive which would be large enough to becomestuck between the fan blades.