Windscreen wiper device with drive head to shaft connection

A windshield wiper assembly, said assembly comprising:

• an elongated, rotatable motor shaft defining a longitudinal axis, said motor shalt includes a cylindrical main portion, a first free end portion and a second flee end portion, the cylindrical main portion has a first outer diameter and the second free end portion includes means for rotational articulation of said motor shaft by a geared motor unit, said first free end portion includes;
• an outer radial collar connected with and adjacent to said main portion, said outer radial collar defining a first cylindrical outer edge surface substantially parallel with said axis and having a second outer diameter greater than said first diameter, and a conical face which defines a radial annular bearing surface, said conical face includes a plurality of teeth projecting therefrom and radially spaced about said conical face, said teeth each having a length, said teeth having a generally triangular profile in cross-section that is parallel with said motor shaft;
• a cylindrical coupling section connected with and adjacent to said outer radial collar, said coupling section defines a cylindrical, smooth outer surface having a third outer diameter less than said first diameter, wherein said plurality of teeth extend from said outer edge surface to said smooth outer surface;
• a threaded cylindrical end section connected with and adjacent to said cylindrical coupling section, said end section having external threads thereon and having a fourth outer diameter less than said first diameter;
• a driving head of a windshield wiper arm, said head having first and second substantially parallel faces, said first face has a conical countersinking formed therein which defines a radial stop surface and a second cylindrical outer edge surface substantially parallel with said axis, said second face has a cylindrical bore formed therein which is aligned with and extends into said conical countersinking;
• a threaded nut, said nut includes a clamping face;
• said free end portion of said shaft is coupled to said driving head, wherein said threaded end section passes through the cylindrical bore to extend from said first face such that the cylindrical coupling section lies within said bore, said threaded nut engages said threaded end section, with said clamping face engaging said first face of said head thus providing axial clamping force such that said teeth are embedded into said conical countersinking and the radial annular bearing surface engages said radial stop surface.