PURPOSE: A rotary cleaner capable of cleaning over the whole cleaned surface wherein rotation is transmitted through a spur gear having side surfaces slanted relative to the axis of a rotary shaft on which a eleaning means is fitted.

CONSTITUTION: A first gear 8 is a spur gear so fitted on the rotary shaft 6 that its side faces are slanted relative to the axis of the shaft 6, and has an O.D. smaller that that of a cleaning means 7. A second gear 9 is engaged with, and symmetric with, the first gear 8. With the shaft 6 rotated through the gears 8 and 9, the range l1 of the means 7 moves rightward and leftward. The distance l2 from a right wall 2 to the end of that portion of the means 7 on the right of the gear 8 is properly selected so that, during one rotation of the shaft 6, no portion of the means 7 fails to contact the cleaned surface.