Abstract: A reactor includes a first core, a second core, and coils. The first core and the second core each include a plate-shaped base and two legs that extend from one plate surface of the base and are arranged in a layout direction. The legs of the first core are extended toward and spaced apart from the legs of the second core. Each of the bases includes narrow portions and a wide portion. The narrow portions are respectively arranged at two ends of the base in the layout direction. The narrow portions each include an end surface that is flush with a side surface of a corresponding one of the legs in a thickness-wise direction. The wide portion is arranged between the two narrow portions. The wide portion has a larger dimension in a widthwise direction than a maximum dimension of the legs in the widthwise direction.

Abstract: In a rotating electrical machine, when a stator winding is wound in concentrated winding, an improvement in performance is achieved by reducing a magnetomotive force harmonic without reducing a fundamental wave magnetic flux generated by a stator. A rotating electrical machine (10) includes a rotor (18), and two stators (14, 16) opposed with the rotor (18) being interposed therebetween either on both sides of the rotor (18) in the axial direction or on both sides of the rotor (18) in the radial direction. Stator windings (22) provided in a plurality of portions in the circumferential direction of each stator (14, 16) are wound in concentrated winding. The directions of magnetic fluxes generated by stator windings (22) having the same phase in the stators (14, 16) are in mutually opposite directions with respect to either the axial direction or the radial direction.

Abstract: In a rotating electrical machine, when a stator winding is wound in concentrated winding, an improvement in performance is achieved by reducing a magnetomotive force harmonic without reducing a fundamental wave magnetic flux generated by a stator. A rotating electrical machine (10) includes a rotor (18), and two stators (14, 16) opposed with the rotor (18) being interposed therebetween either on both sides of the rotor (18) in the axial direction or on both sides of the rotor (18) in the radial direction. Stator windings (22) provided in a plurality of portions in the circumferential direction of each stator (14, 16) are wound in concentrated winding. The directions of magnetic fluxes generated by stator windings (22) having the same phase in the stators (14, 16) are in mutually opposite directions with respect to either the axial direction or the radial direction.

Abstract: A vibrating transducer is coupled to one end of an elongated vibrating plate and a receiving transducer is coupled to the other end of the vibrating plate. Langevin transducers are used for the vibrating and receiving transducers. Each transducer includes a pair of annular piezoelectric elements. The vibrating transducer is connected to an oscillator. A controller controls the oscillator. Detection signals of a voltage sensor, which detects the vibrating state of the receiving side of the vibrating plate, are fed back to the controller. The controller controls the oscillator such that the phase difference between the vibration of the vibrating side and the receiving side is within a predetermined range and that the receiving side is vibrated by amplitude greater than or equal to a predetermined amplitude.

Abstract: An apparatus for levitating objects has an elongated diaphragm and a transducer. The diaphragm has a first end portion and a second end portion. The first end portion is fixed to a horn and the second end portion is fixed to a supporting member. The transducer is connected to only the horn. The transducer vibrates the diaphragm and an object is levitated above a surface of the diaphragm by radiation pressure of a sound wave generated from the diaphragm. Therefore, the elongated diaphragm can be vibrated by one transducer in a stable condition with a simple structure.

Abstract: A vibrating transducer is coupled to one end of an elongated vibrating plate and a receiving transducer is coupled to the other end of the vibrating plate. Langevin transducers are used for the vibrating and receiving transducers. Each transducer includes a pair of annular piezoelectric elements. The vibrating transducer is connected to an oscillator. A controller controls the oscillator. Detection signals of a voltage sensor, which detects the vibrating state of the receiving side of the vibrating plate, are fed back to the controller. The controller controls the oscillator such that the phase difference between the vibration of the vibrating side and the receiving side is within a predetermined range and that the receiving side is vibrated by amplitude greater than or equal to a predetermined amplitude.

Abstract: An apparatus for levitating objects has an elongated diaphragm and a transducer. The diaphragm has a first end portion and a second end portion. The first end portion is fixed to a horn and the second end portion is fixed to a supporting member. The transducer is connected to only the horn. The transducer vibrates the diaphragm and an object is levitated above a surface of the diaphragm by radiation pressure of a sound wave generated from the diaphragm. Therefore, the elongated diaphragm can be vibrated by one transducer in a stable condition with a simple structure.

Abstract: When a mobile unit moves with a motor driven by electric power supplied by a power supply line without a contact when the mobile unit moves where the power supply line exists. The electric power supplied without a contact is also used in charging a electric double layer capacitor. Since the charging current is limited by limiting resistance, the motor can be supplied with sufficient power although the electric double layer capacitor is in a vacant (completely discharged) state.

Abstract: Hall ICs 23u, 23v and 23w are provided to detect the magnetic fields of magnetic regions 8 of a rotor 9 and are offset in position by an electrical angle of 30° from central positions of a U-phase stator pole 1, V-phase stator pole 6 and W-phase stator pole 2. A driving circuit 21 controls the timing of rotor driving signals that are supplied to respective stator coils for respective phases based upon rotor position signals outputted from the Hall ICs 23u through 23w. For example, in order to rotate the rotor in a forward direction, the driving circuit 21 controls the timing of the rotor driving signals according to a first logic. Similarly, in order to rotate the rotor in a reverse direction, the driving circuit 21 controls the timing of the rotor driving signals according to a second logic.

Abstract: When a mobile unit moves with a motor driven by electric power supplied by a power supply line without a contact when the mobile unit moves where the power supply line exists. The electric power supplied without a contact is also used in charging a electric double layer capacitor. Since the charging current is limited by limiting resistance, the motor can be supplied with sufficient power although the electric double layer capacitor is in a vacant (completely discharged) state.

Abstract: An inductor-capacitor series resonant circuit is connected in series with a thyristor or other unidirectionally conductive semiconductor switch to form a resonant network, one resonant network for each stator phase winding of a switched reluctance motor to be connected in parallel to the stator phase winding. Zero current switching is achieved by selecting the resonant frequency such that the inductor and capacitor resonate in a time period during both turn-on and turn-off of the semiconductor switches. A C-dump circuit is included in one embodiment for increased power transfer efficiency.

Abstract: A power feeding device of three-leg core type having a primary and secondary cores which appear to be a three-leg core cut into two pieces at the legs and form a magnetic circuit including gaps by being coupled to face the cut surfaces, and a primary and secondary windings wound coaxially around the central leg section, with the primary core and primary winding constituting the power supply part and the secondary core and secondary winding constituting the power receiving part. The power feeding device based on this winding structure achieves a far better power transfer efficiency as compared with the conventional counterpart having the primary and secondary windings wound separately on a pair of E-shape cores.