Window cleaning tool

A window cleaning tool comprising:

• an internal unit comprising an internal unit housing, an internal unit blade holder disposed rotatably with respect to the internal unit housing, an internal unit wiper having an internal unit blade fixed to the internal unit blade holder and protruding toward an inner surface of glass, and a total of two internal unit magnet assemblies respectively disposed at both sides of the internal unit housing;
• and
• an external unit comprising an external housing, an external unit blade holder disposed rotatably with respect to the external unit housing, an external unit wiper having an external unit blade fixed to the external unit blade holder and protruding toward an outer surface of glass, and a total of two external unit magnet assemblies respectively disposed at both sides of the external unit housing and applying attraction between the internal unit magnetic assemblies and the external unit magnetic assemblies,
• wherein when the internal unit moves up, a front end of the internal unit blade rotates away from the inner surface of the glass and a front end of the external unit blade rotates away from an outer surface of the glass, and
• when the internal unit moves down, the front ends of the internal unit blade and the external unit blade rotate toward the surface of the glass to be pressed,
• wherein the external unit magnetic assemblies each comprise:
• a magnet generating attraction between the internal unit magnetic assembly and the magnet;
• a casing accommodating the magnet;
• upper guide rollers disposed on both sides of the casing;
• and
• lower guide rollers formed at lower corners of the casing and coming in contact with the glass, and
• the external unit housing comprises guide rails having an inclined portion, the guide rails providing paths enabling the upper guide rollers to roll through the inclined portion up and down.