Method and apparatus for cleaning step boards of escalator

A method for cleaning the step boards of an escalator and an apparatus for carrying out the method. The apparatus comprises a holding unit to be fixedly placed at the entrance or at the exit of an escalator, a cleaning unit having a driving means, a power transmitting system and rotary brushes mounted on the holding unit so as to be shiftable widthwise of the escalator, and a pressing means to move the cleaning unit so that the rotary brushes are pressed against each step board of the escalator. Each rotary brush is furnished with a plurality of rows of bristle groups extending helically over the circumference of the cylindrical body thereof, and the individual bristles of each row of the bristle group are inclined both at an angle with respect to the axial direction of the cylindrical body and at an angle with respect to the radial direction of the cylindrical body. The directions of inclination of the bristles of each bristle group with respect to the axial direction of the cylindrical body and with respect to the radial direction of the cylindrical body are opposite to the corresponding directions of inclination of the bristles of the adjacent bristle groups respectively, so that the bristles are able to brush the surfaces of the step boards, the side surfaces of the cleats of the step boards and the bottoms of the grooves between the cleats when the rotary brushes are rotated.