| 摘要 |
1,218,724. Electric motors. SIEMENS A.G. 3 March, 1969 [2 March, 1968], No. 11298/69. Heading H2A. A pump is driven by a commutator-less D.C. motor whose rotor 1 is mounted in the sealed pump chamber and whose stator winding 9 and associated semi-conductor elements 10 are mounted outside that chamber. The semiconductor elements 10, which may be magnetoresistors or Hall generators, sense the position of the permanent magnet rotor for controlling a circuit for commutation in the winding 9. As shown the rotor is mounted in bearings 5, 7 and comprises an impeller 3 and a cylindrical permanent magnet 2. The magnet preferably has two poles and is made of a material which is corrosion-resistant, e.g. barium ferrite or aluminium nickel-cobalt alloy, and has a preferred direction of magnetization. The pump chamber comprises inlet and outlet ducts 11, 12 and a sleeve 8 in the rotor-stator gap. The impeller 3 and the chamber may be made of polymethylmethacrylate, polyethylene or corrosion-resistance metals. The pump may be used for electrolytes or for radio-active, corrosive or poisonous liquids and may be used in automobiles. |
