Abstract: A motor includes a stator, a first rotor and a second rotor. The stator has a plurality of outer teeth projecting outward from an annular stator yoke, a plurality of inner teeth projecting inward from the stator yoke, and windings wound on both of the teeth. Instead of providing both of the teeth with the windings, toroidal windings can be wound on the stator yoke at each section sandwiched between the slots, which stator yoke is disposed between each one of the inner slots and corresponding each one of the outer slots. This motor is structured such that the phases of cogging torque and torque ripple existing between the stator and the second rotor can be reversed with respect to the phases of cogging torque and torque ripple existing between the stator and the first rotor.

Abstract: A motor includes a stator with an annular stator yoke, a stator core having a plurality of inner and outer teeth projecting from the stator yoke toward inside and outside respectively, a plurality of coils wound on the stator core, and an inner rotor and an outer rotor confronting the inner and outer teeth respectively via an air-gap, and having an permanent magnet respectively. The number of slots “S” and the number of poles “P” establish a relation of S:P=3:2N?1, where N is an integer equal to 1 or more, and a case when 2N?1 becomes a multiple of 3 is excluded.

Abstract: Having a stator core including a yoke, a plurality of inside teeth, and a plurality of outside teeth, an inside rotor, and an output rotor, the inside slot open angle/inside pole angle and the outside slot open angle/outside pole angle are determined so that the inside cogging torque due to rotation of the inside rotor and the outside cogging torque due to rotation of the outside rotor may cancel each other in inverted phases. Plural combinations are provided so that the amplitude of inside cogging torque and the amplitude of outside cogging torque due to rotation of outside rotor maybe approximate values in inverted phase, and the combination of the highest combined voltage value of the both induced voltage is selected.

Abstract: A motor includes a stator formed of a stator iron-core having salient pole iron-cores and windings, and a rotor having a rotor iron-core in which permanent magnets are buried. A magnetic pole centerline connecting a rotary center of the rotor to a magnetic pole center crosses an external shape of the rotor iron-core at end point X, and the magnetic-pole boundary line connecting the rotary center to a magnetic pole boundary point crosses the external shape of the rotor iron-core at end point Z. A straight line angled at a given angle ?a from the magnetic pole centerline has end point A. Then a sectional view of the rotor iron-core shows an arc drawn between the end points X and A, and the arc's center is the rotary center. The end points A and Z are connected by one or more than one straight lines in series.

Abstract: A motor includes a stator and a rotor. The stator is configured by winding a coil around a stator core which includes a salient-pole core. The rotor has a rotor core made by laminating thin and highly permeable iron sheets. The rotor core has multiple permanent magnet embedding holes, and a permanent magnet is embedded in each of the permanent magnet embedding holes. A cross-section of the permanent magnet is a rectangle with a long side in a rotating direction and a short side perpendicular to the long side. A cross section of the permanent magnet embedding hole is formed by an embedding hole's long side corresponding to the long side and an embedding hole's short side corresponding to the short side. The embedding hole's short side has a first protrusion and a flat portion. The embedding hole's long side to an inner diameter side has a second protrusion on its both ends.

Abstract: By means of preventing counterfeits on the market from entering a distribution channel, the benefit of manufacturers, dealers, distributors, and consumers forming the distribution channel. First, a data server reads ID data of a non-contact tag 11 and of a reader 12, creates data files thereof, and stores the data files in a database. The reader 12 connected to the Internet reads its own ID data and sends it to an authentication server. The authentication server checks the received ID data of the reader 12 against the data file of the reader 12 stored in the database. If the two are identical, the reader is authenticated. The authenticated reader 12 reads the ID data of the non-contact tag 11 embedded in a product and sends it to the authentication server. The authentication server checks the received ID data of the non-contact tag 11 against the data file of the non-contact tag stored in the database.