Patent ID: 7665173

Claim:
An automated cleaning device for cleaning a generally vertically extending exterior surface of a building comprising: a housing, the housing sized and shaped to permit cleaning of the generally vertically extending exterior surface of a building while minimizing liquid splashing away from the building during a cleaning operation; at least one cleaning element disposed in the housing and configured to rotate about a generally horizontal axis, the cleaning element having a horizontal length greater than its height; said cleaning element including a plurality of outwardly extending cleaning vanes extending at least partially beyond the housing and configured to contact the generally vertically extending exterior surface of the building when the cleaning element is rotated; a first motor disposed on the housing operable to rotate the cleaning element; a cleaning liquid supply system provided to the housing, including a plurality of applicators, the plurality of applicators located and configured to spray cleaning liquid onto the generally vertically extending exterior surface during the cleaning operation; a second motor disposed on the housing operable to control vertical movement of the housing relative to the generally vertically extending exterior surface of the building during cleaning of the surface; and a counterforce system disposed on the housing, the counterforce system configured to provide a substantially perpendicular continuous force on the housing and cleaning element towards the generally vertically extending exterior surface of the building without the use of restraining cables to maintain the cleaning vanes in continuous contact with the generally vertically extending exterior surface of the building during the cleaning operation.