GB413026A - Improvements in or relating to dynamo-electric variable speed power transmitting mechanisms - Google Patents

Abstract

413,026. Systems for transmitting mechanical power; homopolar machines. JAPOLSKY, N., 35, Cholmeley Crescent, Highgate, London. Jan. 18, 1933, No. 1656. [Classes 35 and 38 (iv).] A dynamo - electric power transmitting mechanism comprises two homo-polar machines, the armature, polepieces and field winding of each being almost entirely surrounded by an enclosure of magnetic material to shield them from any magnetic field arising in the other set of elements. The enclosure comprises an outer casing A with an internal annular extension A', and two end covers B<1>, B<2> secured to the pole pieces C<1>, C<2>. The armature discs D<1>, D<2> are fixed on the shafts E', E<2> respectively and are excited by the field windings K<1>, K<2>. The discs rotate in mercury I and the adjacent ends of the shafts are electrically connected through a mass of mercury. The bearings of the shafts are insulated by sleeves G, J. When the fields are excited and one of the shafts is driven, a current passes through both discs causing the armature of the other element to rotate. By regulating the strength of the magnetic fields, the speed ratio of the shafts can be varied. In modifications (not shown), the discs are of different sizes and the shafts may be parallel but not coaxial or may be inclined to each other. In Fig. 8, in order to prevent reaction due to current in the armatures, radial slots L<1>, L<2> and a dividing slot M in a medial plane, are provided, either open or filled with insulating material, and the electrical connection is re-established by an outer conducting ring N. Again, to prevent inequality due to the slots L<1>, L<2>, plates of magnetic material P<1>, p<2> are fitted to the faces of the internal extension A<1>. In order to give a compounding effect, the armatures are provided with curved radial slots provided with covering sheets of ferromagnetic material.