Patent application number | Description | Published |
20100133939 | MOTOR - A motor including a stator and a rotor is disclosed. The rotor includes a first unit and a second unit. The first unit includes an N-pole first magnet and an S-pole second magnet. The first and the second magnets are alternately arranged along a circumferential direction of the rotor at equal angular intervals to form magnetic pole portions. The second unit includes an N-pole or S-pole third magnet and a salient pole arranged in the rotor core. The salient pole functions as a magnetic pole that differs from the third magnet. The third magnet and the salient pole are alternately arranged along the circumferential direction of the rotor to form magnetic pole portions. The number of magnetic pole portions of the second unit is the same as the number of magnetic pole portions of the first unit. The third magnet and the magnet of the first unit having the same pole as the third magnet are aligned in the axial direction of the rotor. | 06-03-2010 |
20100148612 | BRUSHLESS MOTOR - A brushless motor including a stator having teeth and a rotor having magnetic pole portions is disclosed. The magnetic pole portions are arranged to have the same polarities as each other. The rotor includes gaps that function as magnetic resistance at circumferential ends of each of the magnetic pole portions so that an iron core portion is formed between the circumferentially adjacent magnetic pole portions. Magnetic flux of the magnetic pole portions passes through the iron core portion along the radial direction. The gaps include a first gap located on the leading end of the magnetic pole portion in the rotation direction of the rotor and a second gap located on the trailing end of the magnetic pole portion in the rotation direction of the rotor. The circumferential width of the first gap is set to be greater than the circumferential width of the second gap. | 06-17-2010 |
20100301695 | Rotor and Motor - A motor includes a rotor and a stator. The rotor includes a plurality of magnets, which function as first magnetic poles, and salient poles, which function as second magnetic poles. A ratio X | 12-02-2010 |
20100308680 | Rotor and Motor - A motor is disclosed that includes a rotor having a consequent-pole structure. The rotor core of the rotor includes a magnetic flux dividing portion at each position that faces one of the magnets. Each magnetic flux dividing portion forcibly divides magnetic flux in the vicinity of the backside of the corresponding magnet to both sides in the circumferential direction. | 12-09-2010 |
20110140562 | MOTOR - A motor having a rotor and a stator is disclosed. The rotor is a consequent-pole rotor having a rotor core, a plurality of magnets, and a plurality of salient poles. The stator includes a plurality of teeth. A first auxiliary groove is formed in a surface of each salient pole that is opposed to the teeth. Each first auxiliary groove has first and second side surfaces facing each other in the circumferential direction. The first side surface is closer to a circumferential center of the salient pole than the second side surface. When the angle from the circumferential center line to the first side surface of each salient pole about the axis of the rotor is represented by KC1, the opening angle between the circumferential ends of the distal end of each tooth about the axis is represented by KA, and the opening angle between the circumferential ends of each salient pole about the axis is represented by KB, the following expression is satisfied: KC1=KA−KB/2. | 06-16-2011 |
20110148240 | MOTOR - A motor having a rotor and a stator is disclosed. The rotor is a consequent-pole rotor having a rotor core, a plurality of magnets, and a plurality of salient poles. The stator includes a stator core and multiphase coils. Each coil is wound about the teeth by distributed winding, in such a manner as to wind two or more consecutive teeth in single winding. The opening degree each of salient pole opposed to the distal ends of the teeth is set greater than or equal to twice the opening angle of the distal end of each tooth. | 06-23-2011 |
20110181230 | MOTOR - A motor including a stator, a rotor, and a current supply unit. The stator includes a stator core, which has a plurality of teeth, and a plurality of coils, which are wound around the teeth. The rotor includes a plurality of magnets, which function as first magnetic poles, and salient poles, which function as second magnetic poles. Each of the salient poles is arranged between adjacent magnets spaced apart by a clearance from the magnets. When P represents the number of poles in the rotor and S represents the number of coils, a ratio P/S of the pole number P and the coil number S is represented by (4n−2)/3m (where n and m are integers that are greater than or equal to 2). The plurality of coils includes a plurality of coil groups including coils for three phases. The current supply unit executes a different current control for each coil groups. | 07-28-2011 |
20110193440 | MOTOR - A motor having a rotor and a stator is disclosed. A motor having a rotor and as stator is disclosed. The rotor is a consequent-pole rotor having a rotor core, a plurality of magnets, and a plurality of salient poles. The stator includes a plurality of teeth. The stator is arranged to be opposite to the rotor with a gap along the radial direction. The gap between the stator and the rotor is set to satisfy an expression 1 | 08-11-2011 |
20110204833 | CONTROLLER FOR MOTOR - A controller for use with a motor including a stator, around which three-phase coils are wound, and a rotor, which includes a magnet functioning as a first magnetic pole and a salient pole of a core functioning as a second magnetic pole. The controller supplies the three-phase coils with excitation currents having a predetermined phase difference from one another to drive and rotate the rotor. The controller includes a current adjustment unit that adjusts a fundamental wave current using high-order currents for third order and ninth order components in a q-axis to reduce torque ripple. The excitation current is generated based on the fundamental wave current adjusted by the current adjustment unit. | 08-25-2011 |
20110309707 | MOTOR - There is provided a motor including a rotor and a stator arranged outside the rotor in the radial direction. The rotor includes a rotor core, a plurality of magnets arranged at equal intervals in the circumferential direction of the rotor core and functioning as one magnetic pole, and salient poles integrated with the rotor core, each arranged between adjacent magnets and at a distance from the magnets. The salient poles function as the other magnetic pole. A stator has a stator core having a plurality of teeth extending in the radial direction of the stator and arranged at equal intervals in the circumferential direction, and multi-phase coils attached to the teeth. The plurality of salient poles are arranged to have center portions arranged at equal intervals in the circumferential direction, and each have an outer surface extending in the circumferential direction in a range of a predetermined opening angle having an axis of the rotor as a center. A first opening angle serving as an opening angle of an outer surface of a first salient pole is different from a second opening angle serving as an opening angle of an outer surface of a second salient pole. | 12-22-2011 |
20120001509 | MOTOR AND ROTOR - A motor including a stator and a rotor. The stator includes teeth and windings. Each tooth has a distal portion defined by a radially inward side of the stator. The rotor, which is arranged inward in the radial direction from the stator, includes a rotor core, magnets, and salient poles. Each salient pole is separated by a void from the magnet that is adjacent in the circumferential direction. The distal portion of each tooth is longer than a radially outward side of each magnet. | 01-05-2012 |
20120019089 | MOTOR - A motor including a rotor and a stator. The rotor includes a rotor core, magnet pole portions, and core pole portions. First magnetic pole portions, which are the magnet pole portions or the core pole portions, each include a first and second opposing parts arranged in an axial direction. Each first opposing part includes an auxiliary groove, and each second opposing part does not include an auxiliary groove. Where M (°) represents an open angle of the first magnetic pole portion, G (°) represents an open angle of the void, and L represents the number of teeth, an angle D | 01-26-2012 |
20120175987 | BRUSHLESS MOTOR - A brushless motor including a stator having teeth and a rotor having magnetic pole portions is disclosed. The magnetic pole portions are arranged to have the same polarities as each other. The rotor includes gaps that function as magnetic resistance at circumferential ends of each of the magnetic pole portions so that an iron core portion is formed between the circumferentially adjacent magnetic pole portions. Magnetic flux of the magnetic pole portions passes through the iron core portion along the radial direction. The gaps include a first gap located on the leading end of the magnetic pole portion in the rotation direction of the rotor and a second gap located on the trailing end of the magnetic pole portion in the rotation direction of the rotor. The circumferential width of the first gap is set to be greater than the circumferential width of the second gap. | 07-12-2012 |
20120248919 | MOTOR AND ELECTRIC PUMP - A motor in which drive current supplied to a winding is controlled in accordance with a rotational position of a rotor detected from a waveform of an induced voltage between phases. The motor is provided with a stator including 3×n teeth and windings for three phases. A rotor includes a rotor core, an n number of magnets, and an n number of salient poles. The magnets function as one of the magnetic poles, the salient poles function as the other one of the magnetic poles. Each salient pole is spaced apart by a gap from the adjacent ones of the magnets in the circumferential direction. The magnets and gap are arranged inward in the radial direction from the rotor core. An electrical angle between two ends of each magnet is set to be smaller than an electrical angle between two ends of each salient pole. | 10-04-2012 |
20130106208 | ROTOR AND MOTOR | 05-02-2013 |
20130106230 | ROTOR AND MOTOR | 05-02-2013 |
20130113329 | ROTOR AND MOTOR - A rotor is provided with a first rotation member having a plurality of first claw poles in a circumferential direction and a second rotation member having a plurality of second claw poles in a circumferential direction. By of fitting each second claw pole in a cutout portion between first claw poles and by fitting each first claw pole in a cutout portion between second claw poles, the first rotation member and the second rotation member are assembled to each other. At least either one of the first rotation member and the second rotation member is formed of a magnet. Based on a magnetic field generated by the magnet, the first claw poles and the second claw poles have alternating north poles and south poles in the circumferential direction. | 05-09-2013 |
20130121856 | ROTOR AND MOTOR - A rotor includes a first rotor core, a second rotor core, a field magnet, and an auxiliary magnet. The first rotor core includes a first core base and a plurality of first hook-shaped poles. The second rotor core includes a second core base and a plurality of second hook-shaped poles. The first and second hook-shaped poles are alternately arranged in a circumferential direction of the rotor. The field magnet is arranged between the first and second core bases in an axial direction. The field magnet cause the first hook-shaped poles to function as first poles and the second hook-shaped poles to function as second poles. The auxiliary magnet includes at least two interpolar magnet portions, which are integrally formed. Each interpolar magnet portion is arranged in a void between the first hook-shaped pole and the second hook-shaped pole and magnetized in the circumferential direction. | 05-16-2013 |
20130313938 | BRUSHLESS MOTOR - A brushless motor includes a first rotor core, a second rotor core, and a field magnet member. The first rotor core includes primary projecting pieces arranged along a circumferential direction at equal intervals. The second rotor core has the same shape as the first rotor core, and includes secondary projecting pieces arranged along the circumferential direction at equal intervals. The secondary projecting pieces are positioned between the primary projecting pieces that are adjacent to one another in the circumferential direction. The field magnet member is arranged between the first rotor core and the second rotor core. The field magnet member is magnetized along an axial direction to generate primary magnetic poles in the primary projecting pieces, and generate secondary magnetic poles in the secondary projecting pieces. A rotor includes the first rotor core, the second rotor core, and the field magnet member. | 11-28-2013 |
20140139065 | BRUSHLESS MOTOR AND ROTOR - A brushless motor includes a rotor. The rotor includes a first rotor core, a second rotor core and a field magnet. The first rotor core includes a plurality of first magnetic pole portions arranged in a circumferential direction. The second rotor core includes a plurality of second magnetic pole portions arranged in the circumferential direction. The field magnet is arranged between the first rotor core and the second rotor core in an axial direction. When the field magnet is magnetized in the axial direction, the first magnetic pole portions function as first magnetic poles and the second magnetic pole portions function as second magnetic poles. | 05-22-2014 |
20140139079 | ROTOR AND BRUSHLESS MOTOR - A rotor includes a first rotor core, a second rotor core, a field magnet, and a detected portion. The first rotor core includes a first core base and a plurality of first claw-shaped magnetic pole portions. The second rotor core includes a second core base and a plurality of second claw-shaped magnetic pole portions. The first and second core bases face to each other, and the first and second claw-shaped magnetic pole portions are alternately arranged in the circumferential direction. The field magnet is located between the first and second core bases in the axial direction. The field magnet has the first claw-shaped magnetic pole portion function as a first magnetic pole and has the second claw-shaped magnetic pole portion function as a second magnetic pole. A detected portion, which generates a magnetic flux, is arranged at an outer axial end surface of the first rotor core. | 05-22-2014 |
20140203677 | ROTOR, STATOR AND MOTOR - A rotor with four axially stacked rotor cores, and a plurality of field magnets interposed between them. Each rotor core includes a rotor-side claw-shaped magnetic pole. Each rotor-side claw-shaped magnetic poles are respectively extending from and formed on each rotor core at equal angle intervals. Tip end surfaces of the first and third rotor-side claw-shaped magnetic pole abut against or are closely opposed to each other axially. Tip end surfaces of the second and fourth rotor-side claw-shaped magnetic poles abut against or are closely opposed to each other in the axial direction. The plurality of field magnets are magnetized in the axial direction such that the field magnets causes the first and third rotor-side claw-shaped magnetic poles to function as first magnetic poles, and cause the second and fourth rotor-side claw-shaped magnetic poles to function as second magnetic poles. | 07-24-2014 |
20140252904 | MOTOR - A motor includes a stator, a rotor and a case. The rotor includes a first rotor core, a second rotor core, and a field magnet. Each of the first rotor core and the second rotor core includes a core base and a plurality of claw poles. The field magnet is located between the core bases. The case includes a cylindrical yoke housing and a lid. To balance magnetic flux from the first rotor core with magnetic flux from the second rotor core, the distance between the rotor and the stator is varied from the distance between the rotor and the yoke housing or the teeth of the stator are shaped to enable magnetic saturation. | 09-11-2014 |
20140265706 | HALF PERMANENT MAGNET MOTOR - A motor includes a rotor and a stator. The rotor includes a plurality of magnets, which function as first magnetic poles, and salient poles, which function as second magnetic poles. A ratio X1:X2 of a quantity X1 of magnetic pole portions of the rotor, which is the sum of the quantity of the magnets and the quantity of the salient poles, and the quantity X2 of slots is 2n:3n (n being a natural number). The sum of a magnetic pole occupying angle θ1 of the magnet and a magnetic pole occupying angle θ2 of the salient pole is 360°. The magnetic pole occupying angle θ1 is set in a range of 180°<θ1≦230°. | 09-18-2014 |