Abstract: An actuator includes a casing, a stationary member having a coil member and mounted in the casing and a movable member having a moving element and supported by the casing. The moving element has a shaft and is supported by the casing so as to be moved in an axial direction of the shaft and in a rotational direction having the axial direction of the shaft as its rotational axis and the moving element is moved in the axial direction and in the rotational direction by causing electric current to flow through the coil member. The stationary member includes a first stationary member for imparting to the movable member a force oriented in the axial direction and a second stationary member for imparting to the movable member a force oriented in the rotational direction, while the coil member includes a first coil member for exciting a first magnetic path passing through the first stationary member and a second coil member for exciting a second magnetic path passing through the second stationary member.

Abstract: In a rolling driving actuator used as a drive source of a power toothbrush, permanent magnets are formed flat plate shape, and constituting a moving object by being attached to grooves formed on an outer peripheral face of a yoke which is press-fitted to and fixed on a shaft. On the other hand, a tubular shaped stator, which is constituted by a coil wound around a bobbin and stationary yokes provided on both side of the bobbin in axial direction of the shaft, is provided to face an outer face of the permanent magnet or an outer face of the yoke of the moving object with a predetermined clearance so that a center axis thereof becomes coaxial with the center axis of the shaft. By supplying an alternating current to the coil, the moving object is driven in rolling driving around the axis of the shaft.

Abstract: A method of non-invasively determining a concentration of an in-vivo component such as blood sugar level (glucose) of a subject is provided. An absorption spectrum of the subject is measured by use of near-infrared light. The concentration of the in-vivo component is determined by use of the absorption spectrum of the subject and a calibration curve. The calibration curve is prepared by determining a plurality of difference absorption spectra that are differences between a plurality of near-infrared absorption spectra of a living body and a reference absorption spectrum selected from the near-infrared absorption spectra, determining a plurality of synthetic absorption spectra, which are obtained by synthesizing each of the difference absorption spectra with a previously measured reference absorption spectrum of the subject, and performing a multivariate analysis with use of the obtained synthetic absorption spectra.

Abstract: In a power toothbrush, an interchangeable brush head is directly fitted to a front end portion of a drive shaft of an actuator. The actuator comprises a first magnetic circuit for moving the drive shaft reciprocally in an axial direction of the drive shaft, and a second magnetic circuit for rotating the drive shaft around a center axis of the drive shaft. The first magnetic circuit and the second magnetic circuit are independently excited by independent driving current having predetermined frequencies and a predetermined phase difference therebetween. Thus, the brush head fitted to the drive shaft can be moved in a composition of reciprocal linear movement and reciprocal rotation. The actuator does not include conventional mechanical elements such as gears or cams so that the actuator can move the drive shaft much faster than that of the conventional actuator.

Abstract: A linear oscillator includes a reciprocating moving part, a case to contain the moving part, and an amplitude control spindle moveably supported in the case. The moving part and the amplitude control spindle reciprocate at a frequency approximately equal to the resonance frequency of the linear oscillator.

Abstract: An actuator includes a casing, a stationary member having a coil member and mounted in the casing and a movable member having a moving element and supported by the casing. The moving element has a shaft and is supported by the casing so as to be moved in an axial direction of the shaft and in a rotational direction having the axial direction of the shaft as its rotational axis and the moving element is moved in the axial direction and in the rotational direction by causing electric current to flow through the coil member. The stationary member includes a first stationary member for imparting to the movable member a force oriented in the axial direction and a second stationary member for imparting to the movable member a force oriented in the rotational direction, while the coil member includes a first coil member for exciting a first magnetic path passing through the first stationary member and a second coil member for exciting a second magnetic path passing through the second stationary member.

Abstract: A linear oscillator includes a reciprocating moving part, a case to contain the moving part, and an amplitude control spindle moveably supported in the case. The moving part and the amplitude control spindle reciprocate at a frequency approximately equal to the resonance frequency of the linear oscillator.

Abstract: A linear oscillator and an electric toothbrush capable of emitting a low noise and of being assembled compact are provided. The linear oscillator, which reciprocates a shaft in an axial direction thereof, includes a plunger movable together with the shaft in the axial direction of the shaft, an elastic member for applying an axially acting resilient force to the plunger, an electromagnetic driving unit operable to reciprocate the plunger in the axial direction of the shaft at a resonant frequency when an alternating current is supplied thereto, and a fixing member restricting rotation of the plunger about an axis thereof within a predetermined angle. The electric toothbrush includes the linear oscillator and a brush head attached to the shaft for use in brushing teeth.

Abstract: A linear oscillator includes a reciprocating moving part, a case to contain the moving part, and an amplitude control spindle moveably supported in the case. The moving part and the amplitude control spindle reciprocate at a frequency approximately equal to the resonance frequency of the linear oscillator.

Abstract: A revolution type actuator having a movable member performing a revolution motion includes a movable member capable of revolving with respect to a fixed member, a plurality of conducting paths which are provided on a face parallel to a trajectory face of the above-mentioned revolution motion and through which currents flow in mutually intersecting directions, power supply which flows currents having different phases through the above-mentioned plurality of conducting paths, and a magnetic field generator which forms a magnetic field perpendicular to the above-mentioned conducting path, in which the above-mentioned movable member revolves due to an electromagnetic force generated by an interaction between a current flowing through said conducting path and a magnetic field generated by the above-mentioned magnetic field generator.

Abstract: A linear oscillator includes a reciprocating moving part, a case to contain the moving part, and an amplitude control spindle moveably supported in the case. The moving part and the amplitude control spindle reciprocate at a frequency approximately equal to the resonance frequency of the linear oscillator.

Abstract: A revolution type actuator having a movable member performing a revolution motion includes a movable member capable of revolving with respect to a fixed member, a plurality of conducting paths which are provided on a face parallel to a trajectory face of the above-mentioned revolution motion and through which currents flow in mutually intersecting directions, power supply which flows currents having different phases through the above-mentioned plurality of conducting paths, and a magnetic field generator which forms a magnetic field perpendicular to the above-mentioned conducting path, in which the above-mentioned movable member revolves due to an electromagnetic force generated by an interaction between a current flowing through said conducting path and a magnetic field generated by the above-mentioned magnetic field generator.

Abstract: The sulfobetaine-containing resin has much improved affinity for magnetic powders. Therefore, by using the same as a binder, it becomes possible to attain good dispersion of magnetic powders superfine in particle size and/or large in amount of magnetization.The binder can be used advantageously in the manufacture of magnetic recording media, such as magnetic tapes and magnetic disks.