Presentation Information
[AP8-04]Development of Non-Contact Stirrer Using HTS Bulk Magnets Cooled by Compact Cryocooler and Levitating Single-Pole Permanent Magnets
*Tetsuo Oka Oka1, Kazuya Yokoyama2, Naomichi Sakai1, Yoshikazu Kato3, Tomokazu Hemmi4 (1. Shibaura Institute of Technology (Japan), 2. Ashikaga University (Japan), 3. SATAKE MultiMix Corporation (Japan), 4. Thermal Block Company Ltd. (Japan))
Keywords:
Bulk Magnet,Permanent Magnet,Levitation,Cryocooler,Stirrer
Non-contact magnetic levitation was a widely promoted phenomenon at the time high-temperature superconductors were discovered. Representative examples are the demonstration models in which small permanent magnets levitate above the superconducting bulk magnet (hereafter referred to as a bulk magnet) cooled in the liquid nitrogen vessels. While many of the applications employed liquid nitrogen cooling, handling liquid nitrogen appears to have hindered the wide industrialization of the products. Meanwhile, cryogenic refrigerators, capable of temperature control, were expected to be practical, but their high cost and limited production amounts have limited their widespread adoption and affordability. Among these, non-contact mixers using magnetic levitation are already sold in the markets. To achieve further widespread use, the development and mass deployment of compact refrigerators capable of operating in the temperature range between liquid helium and liquid nitrogen is anticipated. The trend toward single-use applications in pharmaceutical manufacturing promises to expand the market for non-contact mixers, with a wide variety of sizes and types available. We have designed a large, multi-pole non-contact mixer and successfully developed a device with a large levitation distance of 10 mm and a rotational torque of 2 Nm.