High torque induction motor with rotating magnets in the rotor

This paper describes a new type high torque induction motor which has the rotating magnets in the rotor. The motor basically consists of a usual stator, cylindrical rotor, and inner cylinder of which the surface is covered by a set of magnets. The rotor turns at somewhat less than synchronous speed. The inner cylinder with magnets can revolve freely against a rotor shaft. The magnets revolve synchronized by the rotating magnetic field induced by the stator current. The magnets make the flux in the rotor. Then we can expect torque increase by the increase of the flux. The results of magnetic field analysis indicate the flux is increased. In the experimental results of a test motor which is a 400 W prototype machine, we have obtained the torque increase by approximately 20 percent as anticipated in the magnetic field analysis. Moreover, test results show improvements of efficiency and power factor in the motor operations. The efficiency of the test motor is obtained as high as 10 percent at the rated output over those of a same size conventional induction motor. Although power factor of conventional induction motors is lagging at all times, the test motor can be operated with near unity, leading or lagging by adjusting the ac supplied source voltage.     

Recovering Bi and Sb from electrolyte in copper electrorefining

The separation of antimony and bismuth in copper electrorefining is somewhat difficult and costly. An ion-exchange technique for the removal of the metals from the electrolyte has been practiced recently, although the metals recovered require further processing. Sumitomo Metal Mining has developed a process to recover antimony and bismuth directly from the eluant by an electrowinning process using a mixture of sulfuric acid and sodium chloride as an eluant for the desorption from the resin. The content of bismuth in the antimony metal recovered by this process was less than 0.2%, while the content of antimony in the bismuth metal was less than 0.4%. K. Ando earned his M.Sc. in metallurgical engineering at Kumamoto University in 1986. He is currently a senior scientist at Sumitomo Metal Mining Company. N. Tsuchida earned his Ph.D. in mineral science at Murdoch University, Western Australia, in 1986. He is currently manager of the Niihama nickel refinery at Sumitomo Metal Mining Company.     

Light-emitting polymers and their LED devices

Highly luminous polymers have successfully been prepared by copolymerization of various arylene vinylene units. The random copolymerization of the monomers having different energy gaps or conjugation degrees can generate the irregularity in poly(arylene vinylenes) and enhance the fluorescence of the polymer. Among the copolymers synthesized, the m/p-phenylene vinylene copolymer showed fairly strong fluorescence and gave the most efficient polymer light-emitting diode (P-LED) device because of the good balance of the exciton confinement and the charge transporting property. The optimized P-LED device showed a maximum luminance of 70000 cd/m²