Mitsuba Corporation

National Institute for Materials Science

Naoki Shioda

Ryo Ohori

Yoshichika Kawashima

Masaki Hayata

Naoki Ogata

Yukihiro Isoda

Atsushi Kawasaki

Gensaku Yamakami

Takashi Yatsuda

Provided are a winding device and a motor. A nozzle that feeds out a coil has: a nozzle hole from which the coil is fed out; an inner-diameter round chamfered part formed on an opening edge of a tip of the nozzle; an outer-diameter round chamfered part formed on the outer peripheral edge of the tip of the nozzle. When the wire diameter of the coil is defined as Φc, the inner diameter of the nozzle hole is defined as Φin, the radius of curvature of the inner-diameter round chamfered part is defined as Rin, and the radius of curvature of the outer-diameter round chamfered part is defined as Rout, they satisfy 1.2Φc≤Φin≤1.4Φc, 0.5Φc≤Rin≤Φc, and 0.25Φc≤Rout≤0.5Φc.

Winding device and motor

A rotor, motor and brushless motor are provided. This rotor () includes a rotor core (), permanent magnets (), and a protrusion () protruding radially outward between permanent magnets (). The permanent magnets () has a parallel orientation in which the easy magnetization direction is parallel to the radial direction in the center of the permanent magnets (). The circumferential side faces () of the permanent magnets () contact the protrusion () in the circumferential direction. Connection surfaces () of the permanent magnets () are connected to the circumferential side face () and to the outer peripheral surface () on the radial outer side. The front end () of the protrusion () in the protrusion direction is arranged between the center () of the circumferential side face () in the protrusion direction and the crossing ridge portion () where the circumferential side face () and the connection surface () cross.

Rotor, motor and brushless motor

A motor control device for controlling a brushless motor including a rotor and a three-phase armature coil includes: a position detection unit which detects the rotational position of the rotor; a control unit which outputs, in a first control mode or a second control mode, a first drive signal or a second drive signal to an inverter at a current-supply timing based on the rotational position of the rotor; and the inverter which outputs a first current-supply signal or a second current-supply signal to the three-phase armature coil when the first drive signal or the second drive signal is input. For any two of the three phases, a duty value when the duty of the applied voltages is the same is larger in the second control mode than in the first control mode.

Motor control device, motor control method, and motor unit

A motor includes: a stator having an annular stator core and multiple teeth protruding radially inwards from the stator core; a coil wound around the teeth; a shaft rotating around the rotation axis radially inside of the stator core; a rotor core fixed to the shaft; magnets positioned on the outer peripheral surface of the rotor core; a salient pole positioned between magnets adjacent to each other in the circumferential direction; an applying portion applying a voltage to the coil; and an applying control portion controlling the applying portion. The ratio of the number of magnetic poles of the magnets and the number of teeth is 2:3. The voltage is a rectangular wave, and its application is started when the tip of the salient pole does not face an opening in the teeth.

Motor and brushless wiper motor

A motor and a brushless wiper motor are provided. The motor () includes: a stator (); coils (); a shaft (); a rotor core (); magnets () which are disposed on an outer peripheral surface () of the rotor core () and a radial thickness of which at end portions () on both sides in the circumferential direction around the rotation axis is smaller than a radial thickness in a circumferential intermediate portion; and salient poles () that are formed between magnets () adjacent in the circumferential direction of the outer peripheral surface () of the rotor core () and protrude radially outward from the end portions () of the magnets () in the circumferential direction. The width dimensions of the salient poles () in the radial direction being set to 40&#xb0; or less in a form of an electrical angle.

According to the present invention, a coil is continuously wound in a single pass around each of a series of teeth, and connected to each segment.

Motor

A rotor of a brushless motor includes permanent magnets formed on the outer circumference of a rotating shaft to have a fan shape in an axial cross section, magnetized from the inner radial surface toward the outer radial surface, and arranged at even intervals so that magnetic poles of the outer radial surfaces are disposed alternately with respect to the polarities thereof in the circumferential direction. The outer radial surface of each of the permanent magnets includes a center of curvature on a line segment connecting a center point in the circumferential width on the outer radial surface with the axial center of the rotating shaft, and formed as a cylindrical surface having a radius of curvature smaller than the distance of the line segment. Each of the permanent magnets is magnetized in a parallel orientation so that the orientation of magnetized magnetic flux is parallel to the line segment.

Brushless motor

A method of producing inorganic compound particles is provided. It includes a step of impregnating a melt liquid of second raw particles into first raw particles by heating a raw material including them at a temperature, which equals to or higher than an eutectic temperature between a region-II (solid-liquid phase range) and a region-I (solid phase range) in a phase diagram and lower than the melting temperature of the inorganic compound. The first raw particles contain an element with a melting point equals to or higher than a melting point of the inorganic compound. The second raw particles contain an element with a melting point lower than the inciting point of the inorganic compound. The method also includes a step of synthesizing inorganic compound particles by a synthetic reaction in the first raw particles between the elements contained in the first and second raw particles.

Inorganic-compound particles and process for producing same

In a direct-current motor armaturecorresponding to an 8-pole-10-slot-20-segment or 12-pole-15-slot-30-segment, a connection wirefor short-circuiting segmentshaving the same degree of electric potential is provided to a commutator, a coilis connected electrically to the segmentshaving a potential difference that is equal to a potential difference between the adjacent segments, and the coilis wound around teethto form armature coils. Accordingly, an armature for use in a direct-current motor, a direct-current motor, and a method for winding wires around the armature of the direct-current motor for enabling down-sized direct-current motors having extended product life and enhanced performance can be provided.

Direct-current motor armature, direct-current motor, and method for winding coil around armature of direct-current motor

The windings () wound around each of the teeth () form two coil groups () of three-phase concentrated windings which are disposed point-symmetrically to each other with respect to the rotational shaft. Each of the coil groups () includes a first coil (), in which the windings () are wound around the teeth in a forward direction, and a second coil (), in which the windings () are wound around the teeth in a reverse direction. When each of the teeth () is allocated with a U phase, a V phase, and a W phase in this order in a circumferential direction so that the first coil () wound for each phase is set to be coils of the U phase, the V phase, and the W phase, and the second coil () wound for each phase is set to be coils of the &#x2212;U phase, the &#x2212;V phase, and the &#x2212;W phase, the coils of the U, &#x2212;W, V, &#x2212;U, W and &#x2212;V phases are electrically connected between the adjacent segments () in this order.

Electric motor

A direct current motor with brushes in which an armature is provided with a rotating shaft that is supported by a yoke housing, an armature core that is fitted and fixed to a rotating shaft from the outer side, and a commutator that is provided on the rotating shaft adjacent to the armature core with nine segments arranged in the circumferential direction. The armature core has nine teeth that extend in the radial direction in a radial pattern and nine slots that are formed between the teeth and extend in the axial direction, the segments having the same polarity are connected with short-circuiting members, and a pair of brushes that make sliding contact with the segments is disposed so as to be mutually point symmetric centered on the rotating shaft. According to the preset invention, it is possible to effectively achieve flattening of the direct current motor.

Growing community of inventors

Kiryu, Japan

Naoki Shioda