Air cleaner for engines

An air cleaning device for internal combustion engines, comprising a cyclone duct having a wide air intake and a narrow dust-collecting portion opposite to said air intake, an electrostatic filter mounted within said duct coaxially to the axis of said duct and having plural dust collecting plates and plural discharge plates, wherein said dust collecting plates and discharge plates are alternately disposed with a predetermined interval therebetween and are arranged perpendicular to said axis of said duct, an induction pipe disposed coaxially to the axis of said duct for guiding air to be sucked into the engine, a discharge needle disposed in said induction pipe, and means for applying high voltage to said dust collecting plates, discharge plates and discharge needle.

An air cleaning device for an internal combustion engine comprising a cyclone dust collection duct having an air intake and a dust-collecting portion at the lower part thereof;

• an electrostatic filter mounted within said duct and having dust collecting plates and discharge plates;
• an induction pipe for guiding the air cleaned within the said cyclone dust-collecting duct into the inlet of the engine, said electrostatic filter being mounted between the air intake and the induction pipe;
• and means for applying a high voltage to the electrostatic filter, said means comprising a piezo-electric element engageable by a part of the engine.