Abstract: In a combination of, for example, a rotor having eight magnetic poles and a stator having twelve slots and pulsating components of permeance, which generate a sinusoidal cogging torque having maxima of the same number as the number of poles of the rotor, pressurizing parts arranged in predetermined positions, applying a force at an outer periphery of the stator and directed inwardly cancels the pulsating components of the cogging torque.

Abstract: In a combination of, for example, a rotor having eight magnetic poles and a stator having twelve slots and pulsating components of permeance, which generate a sinusoidal cogging torque having maxima of the same number as the number of poles of the rotor, pressurizing parts arranged in predetermined positions, applying a force at an outer periphery of the stator and directed inwardly cancels the pulsating components of the cogging torque.

Abstract: In a combination of, for example, a rotor having eight magnetic poles and a stator having twelve slots and pulsating components of permeance, which generate a sinusoidal cogging torque having maxima of the same number as the number of poles of the rotor, pressurizing parts arranged in predetermined positions, applying a force at an outer periphery of the stator and directed inwardly cancels the pulsating components of the cogging torque.

Abstract: In a combination of, for example, a rotor having eight magnetic poles and a stator having twelve slots and pulsating components of permeance, which generate a sinusoidal cogging torque having maxima of the same number as the number of poles of the rotor, pressurizing parts arranged in predetermined positions, applying a force at an outer periphery of the stator and directed inwardly cancels the pulsating components of the cogging torque.

Abstract: In a combination of, for example, a rotor having eight magnetic poles and a stator having twelve slots and pulsating components of permeance, which generate a sinusoidal cogging torque having maxima of the same number as the number of poles of the rotor, pressurizing parts arranged in predetermined positions, applying a force at an outer periphery of the stator and directed inwardly cancels the pulsating components of the cogging torque.

Abstract: In a combination of, for example, a rotor having eight magnetic poles and a stator having twelve slots and pulsating components of permeance, which generate a sinusoidal cogging torque having maxima of the same number as the number of poles of the rotor, pressurizing parts arranged in predetermined positions applying a force at an outer periphery of the stator directed inwardly to cancel the pulsating components of the cogging torque.

Abstract: In a combination of, for example, a rotor having eight magnetic poles and a stator having twelve slots and pulsating components of permeance, which generate a sinusoidal cogging torque having maxima of the same number as the number of poles of the rotor, pressurizing parts arranged in predetermined positions applying a force at an outer periphery of the stator directed inwardly to cancel the pulsating components of the cogging torque.

Abstract: A highly accurate rotation angle detection device is realized by correcting a detecting position error caused by a machining error such as deterioration of roundness of an internal diameter of a stator. The rotation angle detection device is provided with a stator (12), which is provided with an exciting winding of one phase and two-phase output windings, and a rotor (13) having salient poles, in which the stator (12) has a plurality of teeth (11), the two-phase output windings are wound around the plurality of teeth, and the plurality of teeth include teeth for which the number of turns of the output windings is N and at least one of teeth for which the number of turns of the output windings is N±m (it is assumed that N and m are positive integers and N>m) and teeth for which the number of turns is m.

Abstract: A highly accurate rotation angle detection device is realized by correcting a detecting position error caused by a machining error such as deterioration of roundness of an internal diameter of a stator. The rotation angle detection device is provided with a stator (12), which is provided with an exciting winding of one phase and two-phase output windings, and a rotor (13) having salient poles, in which the stator (12) has a plurality of teeth (11), the two-phase output windings are wound around the plurality of teeth, and the plurality of teeth include teeth for which the number of turns of the output windings is N and at least one of teeth for which the number of turns of the output windings is N±m (it is assumed that N and m are positive integers and N>m) and teeth for which the number of turns is m.

Abstract: A highly accurate rotation angle detection device is realized by correcting a detecting position error caused by a machining error such as deterioration of roundness of an internal diameter of a stator. The rotation angle detection device is provided with a stator (12), which is provided with an exciting winding of one phase and two-phase output windings, and a rotor (13) having salient poles, in which the stator (12) has a plurality of teeth (11), the two-phase output windings are wound around the plurality of teeth, and the plurality of teeth include teeth for which the number of turns of the output windings is N and at least one of teeth for which the number of turns of the output windings is N±m (it is assumed that N and m are positive integers and N>m) and teeth for which the number of turns is m.

Abstract: A highly accurate rotation angle detection device is realized by correcting a detecting position error caused by a machining error such as deterioration of roundness of an internal diameter of a stator. The rotation angle detection device is provided with a stator (12), which is provided with an exciting winding of one phase and two-phase output windings, and a rotor (13) having salient poles, in which the stator (12) has a plurality of teeth (11), the two-phase output windings are wound around the plurality of teeth, and the plurality of teeth include teeth for which the number of turns of the output windings is N and at least one of teeth for which the number of turns of the output windings is N±m (it is assumed that N and m are positive integers and N>m) and teeth for which the number of turns is m.

Abstract: A motor embedded with magnets having good properties and productivity. A rotor of this motor includes a rotor core with laminated rotor core plates punched out of an electromagnetic steel plate and studded with bonded magnets of a powdered permanent magnet material and a resin in groups of slits located in the rotor core for each pole of the rotor.

Abstract: An optical disc comprises two facing disc units, at least one of which has a recording layer formed on its surface facing to the other disc unit. The disc units are bonded together by a layer of adhesive which may be a room-temperature curing thermosetting adhesive having a glass transition temperature higher than the upper limit of the range of temperatures of environments in which the disc may be used. Alternatively, the adhesive may be a room-temperature curing two-pack epoxy adhesive which comprises a bisphenol epoxy resin base agent and a modified aliphatic polyamine curing agent, and which has a viscosity of 100-1000 cps, a pot life of one hour or more, a cure shrinkage of 1.0% or less, a water absorption, after curing, of 0.2% or less, and a Shore hardness, after curing, of 80-90.

Abstract: An optical disk adapted to resist moisture absorption, warping and static charge is disclosed. The disk includes an SiO.sub.2 film coating over at least a portion of a disk substrate. Additionally, an optical disk having a magnetic film protected by a fluorocarbon polymer is disclosed. Either of such disks can be used individually or, alternatively, they can be used in a laminated structure having two disks laminated in a face-to-face relationship. The laminated structure can be covered with SiO.sub.2 film.

Abstract: A magnetic thin film memory wherein the memory is composed of magnetic thin films with a layer of a higher coercive force and a layer of a lower coercive force via a nonmagnetic layer laminated repetitively, or magnetic thin films having the easy magnetization axis which lies between the perpendicular and the horizontal directions of the magnetic thin film, and information is recorded on the layer of a lower coercive force, or information is recorded by changing the direction of the magnetization by means of a magnetic field applied by two recording lines which cross the magnetic thin film, thereby to obtain a sufficient amplitude of reproduction signal even when the size of the memory is reduced.

Abstract: An optical disc comprises two facing disc units, at least one of which has a recording layer formed on its surface facing to the other disc unit. The disc units are bonded together by a layer of adhesive which may be a room-temperature curing thermosetting adhesive having a glass transition temperature higher than the upper limit of the range of temperatures of environments in which the disc may be used. Alternatively, the adhesive may be a room-temperature curing two-pack epoxy adhesive which comprises a bisphenol epoxy resin base agent and a modified aliphatic polyamine curing agent, and which has a viscosity of 100-1000 cps, a pot life of one hour or more, a cure shrinkage of 1.0% or less, a water absorption, after curing, of 0.2% or less, and a Shore hardness, after curing, of 80-90.

Abstract: An optical disk having a warp preventive film for preventing the warp of the substrate which does not exfoliate for a long period by forming the warp preventive film on a textured area on the substrate surface with a minute embossment, and a method of manufacturing the optical disk by controlling the plasma etching condition for forming a textured area for reinforcing the bonding force of the warp preventive film on the substrate surface, so that the warp preventive film being bonded after forming the textured area may not exfoliate for a long period.