Abstract
Reporters obtained the following quote from the background information supplied by the inventors: ““Field of the Invention“The present invention relates to the technical field of cleaning apparatuses an d, more particularly, toa self-propelled device.“Description of the Prior Art“Conventional methods for cleaning windows of households involve opening or remo ving the windowsfor cleaning. For windows of a building, a suspension frame is set up outside the building, the suspensionframe is controlled to ascend or des cend using a motor, and the windows outside the building are thencleaned by bru shes or water jets. However, a suspension frame has an unstable center of gravit y and thusis susceptible to swinging when blown by the wind. In order to preven t excessive brushing and cleaning ofwindows that may cause slipping of cleaning staff or injuries resulted from falling of cleaning tools, windowscan be washe d only by mild water streams, in a way that the windows may not be thoroughly cl eaned.
NETL
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