Patent ID: 8070561

Claim:
A floor care machine comprising: a machine frame; a drive motor mounted on said machine frame; support elements connected to said machine frame and adapted to at least partially support said floor care machine on a floor surface such that said floor care machine can be moved along the floor surface; a driven head that is rotatably carried relative to said machine frame to be rotatable about a rotation axis, and that is adapted to carry a floor care disc on a bottom of said driven head facing the floor surface; and a drive arrangement that couples said drive motor to said driven head so as to rotationally drive said driven head and enable a height adjustment of said driven head relative to at least one of said support elements so as to adjust a contact pressure of the floor care disc on the floor surface; wherein: said drive arrangement includes a drive element that is rotatably supported so as to be rotatable about said rotation axis, a drive transmission that couples said drive motor to said drive element for rotation with said drive motor, and a driven element that is rotatable about said rotation axis and is coupled to said drive element so that said driven element is rotationally and axially displaceable relative to said drive element about and along said rotation axis; said drive element comprises a central hub, an outer ring that is engaged by said drive transmission, and a plurality of spoke elements that are uniformly rotationally offset from one another and that extend between and interconnect said central hub and said outer ring; said spoke elements respectively have respective first rolling guides that respectively extend along respective partial helical paths about said rotation axis; said driven element comprises first and second partial elements that are arranged on two axially opposite sides of said spoke elements and are connected to one another; said partial elements of said driven element have second rolling guides that respectively extend along said respective partial helical paths, and that respectively face toward and form respective pairs with said first rolling guides; and said drive arrangement further includes plural roller bodies that are respectively interposed between, and are configured and fitted to roll guidedly along, said pairs of said first and second rolling guides.