English to German Tech/Engineering Automation & Robotics Bodenreinigungsroboter

http://www.google.com/patents/EP2279686B1?cl=en


FIG. 44 in general shows the operating position, wherein the rear squeegee 1006 angles back, and both flexure portions are positioned to permit flexure of the squeegee combination. Although the rear squeegee 1006 is formed as a flat panel wall (and alternatives as discussed herein) with a planar bottom, in the operating position as it is angled back by the front squeegee 1004, and a working edge, the edge of the wall and wall bottom, contacts the ground rather than the planar bottom. The contact force, area, angle, flatness and edge profile of this contact is a large contributor to the ***drag*** of the cleaning elements, and as discussed herein, is to be maintained at a sufficiently low level of ***drag*** to permit traction while still enabling the squeegeeing of water on flat or irregular surfaces.

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In addition to contaminants that may be encountered during use, the various cleaning accessories (e.g., brushes, squeegees, etc.) of the device effect the traction of the device. The drag created by these devices, the character of contact (i.e., round, sharp, smooth, flexible, rough, etc.) of the devices, as well as the possibility of slippage caused by contaminants, varies depending on the surface being cleaned. Limiting the areas of contact between the robot and the surface being cleaned reduces attendant friction, which improves tracking and motion. One and one-half pounds of drag force versus three to five pounds of thrust has proven effective in robots weighing approximately 5-10 pounds. Depending on the weight of the robot cleaner, these numbers may vary, but it is noted that acceptable performance occurs at less than about 50% drag, and is improved with less than about 30% drag.