Abstract: A resolver includes a first coil group and a second coil group. The first coil group has a first exciting coil and a first detecting coil that have a multiplication factor of angle of nX (where n is a natural number equal to or greater than three), are placed coaxially with the axis of rotation of the rotor, and each have a ring shape. The second coil group has a second exciting coil and a second detecting coil that have a multiplication factor of angle of (n?1)×, are placed coaxially with the axis of rotation of the rotor, and each have a ring shape. Furthermore, the first coil group and the second coil group are provided at positions different in a radial direction from each other.

Abstract: A resolver includes excitation coils and a detection coil. One of the excitation coils and the detection coil includes a sine coil and a cosine coil that transmit AC signals having phases of the electrical angle different from each other by 90 degrees. Further, the other coil is provided with an annular magnetic pole group in which a plurality of magnetic poles is disposed adjacent to each other in the circumferential direction at a facing face at which the rotor and the stator face each other. The plurality of sine coils and the plurality of the cosine coils are alternately disposed adjacent to each other in the circumferential direction at the facing face. The circumferential intervals between the magnetic poles included in the excitation coils and the detection coil are identical.

Abstract: A resolver includes: a sine exciting coil and a cosine exciting coil; a detecting coil that is provided to a rotor and is placed facing the sine exciting coil and the cosine exciting coil; an exciting coil forming a closed circuit, together with the detecting coil, in the rotor; and a sine detecting coil and a cosine detecting coil that are provided to a stator, are placed facing the exciting coil, and transmit alternating current signals that are 90 electrical degrees apart in phase. The multiplication factor of angle of the sine detecting coil, the cosine detecting coil, and the exciting coil is different from the multiplication factor of angle of the sine exciting coil, the cosine exciting coil, and the detecting coil.

Abstract: A resolver includes an excitation coil provided at the rotor or the stator and formed on a sheet-shaped substrate, and a detection coil provided at the rotor or the stator and formed on the sheet-shaped substrate. At least one of the excitation coil and the detection coil is a sine coil and a cosine coil. In the sine coil, sine coil patterns of a pair of comb-shaped closed coils are disposed on the identical layer of the substrate. In the cosine coil, cosine coil patterns of a pair of comb-shaped closed coils are disposed on the identical layer of the substrate. Each of the pair of comb-shaped closed coils includes a first comb-shaped closed coil including an inward first projection and a second comb-shaped closed coil including an outward second projection.

Abstract: A resolver includes a first coil group and a second coil group. The first coil group has a first exciting coil and a first detecting coil that have a multiplication factor of angle of nX (where n is a natural number equal to or greater than three), are placed coaxially with the axis of rotation of the rotor, and each have a ring shape. The second coil group has a second exciting coil and a second detecting coil that have a multiplication factor of angle of (n-1)X, are placed coaxially with the axis of rotation of the rotor, and each have a ring shape. Furthermore, the first coil group and the second coil group are provided at positions different in a radial direction from each other.

Abstract: A position sensor detects the rotational position of a rotor relative to a stator, based on a change in inductance due to a rotation of the rotor fixed to a shaft. The stator is tubular and disposed concentrically with the rotation center of the shaft. The stator includes: magnetic pole pairs protruding from an inner peripheral surface toward the rotation center, and each including a pair of opposing main magnetic poles; auxiliary magnetic poles positioned on both sides of each main magnetic pole, and protruding inward from the inner peripheral surface. The rotor includes at least a pair of protruding poles protruding outward from a reference cylindrical surface at a constant distance from the rotation center. The position sensor includes coil pairs including coils wound on the main magnetic poles of the magnetic pole pairs. The two coils of each of the coil pairs have the same winding direction.

Abstract: A position sensor includes a stator, a rotor, an excitation circuit, and a processing unit. The stator is tubular and disposed concentrically with the center of rotation of the shaft. The stator includes magnetic pole pairs having a pair of magnetic poles protruding from an inner peripheral surface toward the center of rotation and opposed to each other. The rotor is fixed to the shaft and includes at least a pair of protruding poles protruding radially outward from a reference cylindrical surface at a constant distance from the center of rotation. The excitation circuit includes coil pairs wound on the magnetic poles of the respective magnetic pole pairs and a switch for switching on/off of currents to the coil pairs. The processing unit causes the switch to switch during rotation of the rotor, and detects a rotor position based on the magnitude relationship of an inductance between the coil pairs.

Abstract: A drive circuit is provided for a reluctance motor including a stator having multiple salient poles and a rotor having multiple salient poles, and the drive circuit includes a first path used to supply a current for excitation that flows through at least part of a coil wound around a salient pole of the stator or the rotor, and a second path used to supply a current for demagnetization that flows through a different part of the coil that does not coincide with the at least part of the coil.

Abstract: The process for forming an ultrafine-particle film according to this invention is characterized by irradiating the surface of a target of a raw material with laser energy in a predetermined atmosphere under conditions where a plume is generated, exposing a substrate (a base material) directly to the plume generated, and thereby forming a film. The substrate is positioned in the plume at a distance, from the surface of the target of the raw material, of at least the mean free path of atoms and/or molecules of the raw material (or components thereof). By so positioning the substrate, ultrafine particles of the raw material are deposited on the substrate. The plume containing a large amount of ultrafine particles moves at a high speed; and exposure of the substrate, at the specified position relative to the target, to the plume causes strong adhesion of ultrafine particles contained in the plume to the substrate, resulting in formation of a film.

Abstract: A method metallurgically bonds a thin film of easily amorphized material on a metallic substrate having a large thermal conductivity, and then irradiates all or selected portions of the thin film with a pulse laser. The irradiated portions become amorphous by rapidly heating and cooling. Therefore, a whole surface which is an amorphous layer or a part of a surface which is an amorphous layer is obtained. In the latter, a porous amorphous metal layer is obtained by subsequent acid elution and by removing the non-amorphous part.

Abstract: A method of efficiently manufacturing ultra-fine particles of material, comprising a step of applying laser energy to the material in order to generate a plume phenomenon thereon to cause the ultra-fine particles. The material may be selected from various materials such as non-metal materials as well as metal materials.