Rotary travelling surface treatment device

Abstract

A rotary travelling device comprising a main supporting member rotatably around a first axis substantially perpendicular to a travelling surface, a subsidiary supporting member mounted on the main supporting member for free rotation around a second axis substantially parallel to the first axis, a rotary disc mounted rotatably on the subsidiary member, and a driving means for rotating the rotary disc. The central axis of rotation of the rotary disc is not perpendicular but inclined to the travelling surface, and the under surface of the rotary disc comes into inclined contact with the travelling surface. The device is further provided with means for rotating the subsidiary member around the second axis according to the rotation of the main supporting member around the first axis.

Dependencies are inferred from the claim text.