Cleaning device for a rotary cooling air filter

An agricultural machine has a cooling fan with an intake covered by a filter centered on and rotating about an axis. A cleaning apparatus for the filter has a hood nonrotatable about the axis and engaged over only a small portion of an outer face of the filter, a rotatable brush inside the filter fixed in axial alignment with the hood and having bristles engaging through holes in the filter at the hood so that the bristles free particles stuck in the holes, and a fan connected to the hood for exhausting air therefrom along with particles freed by the bristles. The filter has an axially directed and radially extending end and an axially extending and radially directed side. The rotatable brush engages an inner face of the end of the filter and the apparatus includes a second rotatable brush separate from the first-mentioned rotatable brush and engaging an inner face of the side of the filter. The first brush is generally frustoconical and the second brush is generally cylindrical.