JP2012205399A - Motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor capable of reducing torque ripple with a simple configuration.SOLUTION: In a rotor, magnet poles each having a magnet are provided at an equal pitch in the circumferential direction; while in a sensor magnet 17, an angle θs1 formed by an N-pole magnetized part 17c is set to an angle larger than an angle θs2 formed by an S-pole magnetized part 17d. Based on a rotation detection signal generated by rotation operation of the sensor magnet 17, the motor generates a rotation magnet field deviating from the switching timing of the magnetic poles of the rotor.

Description

  The present invention relates to a motor that performs energization control on a stator using a rotation detection sensor.

  In a brushless motor or the like, as described in, for example, Patent Document 1, a sensor magnet that is multipolarly magnetized in the circumferential direction and rotates integrally with a rotor, and a magnetic sensor (for example, a Hall element) disposed opposite to the sensor magnet ) Is detected, and the rotational position of the rotor is detected, and energization control is performed on the stator windings.

  Further, the brushless motor is required to improve torque ripple (torque pulsation) that leads to vibration during rotation of the rotor and noise accompanying the rotation.

Japanese Patent No. 3945696

  However, it is known that the torque ripple described above is reduced by dispersing each order component included in the torque ripple. However, by providing a configuration that reduces such torque ripple, the motor configuration can be reduced. The problem that it will become complicated arises.

  The present invention has been made to solve the above problems, and an object thereof is to provide a motor capable of reducing torque ripple with a simple configuration.

  In order to solve the above-mentioned problem, the invention according to claim 1 is based on a stator that generates a rotating magnetic field by energizing a wound winding, and is arranged to face the stator and based on the rotating magnetic field. And a rotation detection means for outputting a rotation detection signal generated by a rotation operation of the detected member. A motor in which energization control for generating the rotating magnetic field is performed on the stator based on a detection signal, wherein the rotor has magnetic poles having magnets provided at equal pitches in the circumferential direction of the rotor core. The detected member of the rotation detecting means is provided with a plurality of detected portions for generating the rotation detection signal at unequal pitches in the circumferential direction, and rotates with the rotor. On the basis of the rotation detection signal corresponding to the detected portion of the timber, and its gist that a rotating magnetic field that is offset with respect to the switching timing the magnetic poles of the rotor and so as to generate the stator.

  In this invention, the detected member of the rotation detecting means is provided with a plurality of detected portions at unequal pitches in the circumferential direction with respect to the rotor in which the magnetic poles having magnets are provided at the same pitch in the circumferential direction. A rotating magnetic field is generated in the stator based on a rotation detection signal generated by the rotation operation of the member. In other words, the rotation detection signal shifted with respect to the switching timing of the magnetic poles of the rotor is output by the configuration in which the detected portions of the detected members are arranged at unequal pitches, so that the energization timing to the stator windings is Therefore, a rotating magnetic field including an irregular portion in the magnetic attractive force generated between the stator and the rotor is generated. As a result, calculations that shift the energization timing on the control side are not required, and even with a simple configuration that does not use control means with high processing capacity, each component included in the torque ripple can be dispersed, reducing torque ripple. Can be achieved.

  According to a second aspect of the present invention, in the motor according to the first aspect, the winding of the stator is composed of a plurality of phases, and the rotation detecting means outputs a rotation detection signal corresponding to each phase of the winding. The gist is that a plurality of detection units are provided to be generated, and at least one of the detection units of each phase is arranged so as to be shifted from a reference position arranged corresponding to each phase.

  In the present invention, the winding of the stator is composed of a plurality of phases, and the rotation detecting means is provided with a plurality of detectors for generating a rotation detection signal corresponding to each phase of the winding. Then, at least one of the detection units of each phase is arranged so as to be shifted from a reference position arranged corresponding to each phase. In other words, the energization timing of the stator windings is shifted with respect to the overall switching timing of the magnetic poles of the rotor, and the magnetic attractive force generated between the stator and the rotor includes a more irregular portion. A rotating magnetic field can be generated. Thereby, it is possible to further reduce the torque ripple.

  According to a third aspect of the present invention, in the motor according to the first or second aspect, the detected portion of the detected member surrounds the first detected portion and the second detected portion having different angles formed in the circumferential direction. The gist is that they are arranged alternately in the direction.

  In this invention, the detected part of the detected member is configured by alternately arranging the first detected part and the second detected part having different angles formed in the circumferential direction in the circumferential direction. Thereby, the 1st and 2nd to-be-detected part can perform easily the setting for 1 period (electrical angle 360 degrees) of the energization timing to the winding of a stator.

  According to a fourth aspect of the present invention, in the motor of the first or second aspect, the winding of the stator is composed of a plurality of phases, and the detected portion of the detected member has a different angle formed in the circumferential direction. The gist is that at least two combinations of the first detected part and the second detected part are provided.

  In the present invention, the stator winding is composed of a plurality of phases, and the detected portion of the detected member is provided with at least two combinations of the first detected portion and the second detected portion having different angles formed in the circumferential direction. . Accordingly, at least two sets of the first and second detected parts can easily set at least two different energization timings for one cycle (electrical angle 360 °) for the windings of each phase of the stator. Can do.

  According to a fifth aspect of the present invention, in the motor according to the third or fourth aspect, the member to be detected of the rotation detecting means is an N-pole magnetized portion and the second detected portion as the first detected portion. The gist of the present invention is that it is composed of an annular sensor magnet having S-pole magnetized portions and alternately arranged in the circumferential direction.

  In this invention, the member to be detected is composed of an annular sensor magnet in which the magnetized portions magnetized with the first detected portion as the N pole and the second detected portion as the S pole are alternately arranged in the circumferential direction. Is done. Thereby, the member to be detected can be easily configured as an annular sensor magnet.

  According to the present invention, it is possible to provide a motor capable of reducing torque ripple with a simple configuration.

It is a schematic block diagram of the motor in this embodiment. It is a disassembled perspective view of the rotor and sensor magnet in the same embodiment. It is a top view of a sensor magnet. (A)-(c) is a wave form diagram which shows the relationship between an electrical angle and the rotation detection signal of each phase sensor. It is a top view of the sensor magnet in another example.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
As shown in FIG. 1, the motor M of the present embodiment is an inner rotor type brushless motor, and is configured by housing a stator 2 and a rotor 3 inside a motor case 1. The motor case 1 includes a bottomed cylindrical case body 5 and a substantially disc-shaped cover plate 6 that closes an opening of the case body 5. An annular stator 2 is fixed to the inner peripheral surface of the case body 5, and a winding magnetic pole 10 for generating a rotating magnetic field for rotating the rotor 3 is disposed on the teeth 2 a of the stator 2. It is wound through. The winding magnetic pole 10 has three phases of a U phase, a V phase, and a W phase, and is wound around predetermined teeth 2a.

  A rotor 3 having a rotating shaft 11 is disposed inside the stator 2. A base end portion of the rotary shaft 11 formed in a substantially columnar shape is pivotally supported by a bearing 12 provided in the center of the bottom of the case body 5, while a portion on the front end side of the rotary shaft 11 is formed on the cover plate. 6 is supported by a bearing 13 provided at the center in the radial direction. Further, the distal end portion of the rotating shaft 11 passes through the central portion in the radial direction of the cover plate 6 and protrudes outside the motor case 1.

  As shown in FIGS. 1 and 2, a substantially cylindrical rotor core 14 made of a magnetic material is opposed to the rotating shaft 11 in a radial direction at a portion closer to the base end than the central portion in the axial direction. To be fixed. A press-fit hole 14 a that penetrates the rotor core 14 in the axial direction is formed in the central portion in the radial direction of the rotor core 14. The rotor core 14 is fixed so as to rotate integrally with the rotary shaft 11 by press-fitting the rotary shaft 11 into the press-fitting hole 14a. Magnets 15 and 16 are embedded in the rotor core 14 along the axial direction.

  A sensor magnet 17 that is formed in an annular shape and has a plurality of magnetic poles in the circumferential direction is fixed at a position between the tip portion of the rotating shaft 11 and the rotor core 14. The sensor magnet 17 has a plate shape with a constant axial thickness, and has an outer diameter equal to the outer diameter of the rotor core 14. The sensor magnet 17 and the rotor core 14 are fixed at positions separated from each other in the axial direction.

  A circuit board 21 on which a circuit element (not shown) for controlling the motor M is mounted is fixed to the inner surface 6 a of the cover plate 6. The circuit board 21 is opposed to the axial end surface 17a of the sensor magnet 17 on the opposite side of the rotor core 14 in the axial direction. On the circuit board 21, the magnetic sensor 22 is disposed at a position that can face the outer peripheral side portion of the sensor magnet 17 in the axial direction. The magnetic sensor 22 is, for example, a Hall IC, and in order to generate a rotation detection signal corresponding to each phase (U phase, V phase, W phase) of the winding magnetic pole 10, a U-phase sensor element 22u, V phase. The sensor element 22v and the W-phase sensor element 22w are composed of three sensor elements (see FIG. 3). The circuit board 21 is electrically connected to a drive control circuit (not shown) provided outside the motor M.

  As shown in FIG. 2, the sensor magnet 17 fixed to the distal end side of the rotating shaft 11 is formed with a fixing hole 17 b penetrating in a circular shape in the axial direction at the central portion in the radial direction. A portion on the distal end side of the rotating shaft 11 is fitted into the fixing hole 17b. Thereby, the sensor magnet 17 is fixed to the rotating shaft 11 so as to be integrally rotatable with the rotor core 14 in which the magnets 15 and 16 are embedded.

  In the rotor core 14, fitting holes 14b having a rectangular cross section penetrating the rotor core 14 in the axial direction are formed at eight positions at equal angular intervals (equal pitch) of 45 ° in the circumferential direction. In each fitting hole 14b, substantially rectangular parallelepiped magnets 15 and 16 formed along the shape are alternately embedded and fixed in the circumferential direction. The magnet 15 has a radially outer side surface 15a side attached to the N pole and constitutes an N pole 18 on the rotor core 14, and the magnet 16 has a radially outer side surface 16a side magnetized to the S pole and the rotor core 14 has an S pole. 19 is constituted. Therefore, the rotor core 14 has magnetic poles 18 and 19 having opposite magnetic poles arranged at equal pitches alternately in the circumferential direction. Note that the radially inner side surfaces 15b and 16b of the magnets 15 and 16 are magnetic poles opposite to the radially outer side surfaces 15a and 16a.

  As shown in FIG. 3, the sensor magnet 17 of the present embodiment is configured such that the magnetic pole boundary lines Ls <b> 1 to Ls <b> 3 are radial straight lines, and the N pole N pole magnetized portion 17 c and the S pole S pole in the circumferential direction (rotation direction). The magnetized portions 17d are configured as annular magnets arranged alternately. Both magnetized portions 17c and 17d have a fan shape in which the circumferential width increases radially outward, and the circumferential alignment with the magnetic poles 18 and 19 of the rotor core 14 has a one-to-one correspondence. As shown in FIG. The sensor elements 22u, 22v, and 22w on the circuit board 21 are arranged at predetermined intervals in the circumferential direction at positions facing both the magnetized portions 17c and 17d of the sensor magnet 17 in the axial direction. In the motor M of the present embodiment, the rotating magnetic field generated in the winding magnetic pole 10 of the stator 2 is a rotating magnetic field that is shifted with respect to the timing at which the magnetic poles 18 and 19 are switched as the rotor core 14 rotates. The sensor magnet 17 and each sensor element 22u, 22v, 22w are comprised.

  Specifically, in the sensor magnet 17, the angle θs1 formed between the magnetic pole boundary line Ls1 on the counterclockwise direction side of the N pole magnetized portion 17c and the magnetic pole boundary line Ls2 on the clockwise direction side has an S pole magnetized portion 17d. Are formed at an angle larger than the angle θs2 formed by the magnetic pole boundary line Ls3 and the magnetic pole boundary line Ls2, and the magnetized portions 17c and 17d are arranged at unequal pitches. In the sensor magnet 17, when the angles θs1 and θs2 of one N-pole magnetized portion 17c and S-pole magnetized portion 17d are summed, an electrical angle of 360 ° (θs1 + θs2 = 360 °) is obtained.

  The sensor elements 22v and 22w are arranged at a predetermined angle in the circumferential direction from the reference position arranged corresponding to each phase. Here, as the positions where the sensor elements 22u, 22v, and 22w are arranged corresponding to the winding magnetic poles 10 constituted by three phases, rotation detection having a phase difference of 120 ° in electrical angle as the sensor magnet 17 rotates. In order to obtain a signal, a position where an angle (electrical angle) formed by the other two sensor elements with respect to an arbitrary sensor element in the circumferential direction is 120 ° or 240 °, respectively, is a reference.

  In contrast, in the present embodiment, the sensor element 22v is provided with a phase difference of an angle θv from a position where the angle formed by the sensor element 22u and the circumferential direction is an electrical angle of 120 ° (mechanical angle of 30 ° in the present embodiment). It is arranged at the position (position moved in the clockwise direction). In addition, the sensor element 22w has a phase difference of the angle θw (clockwise direction side) from a position where the angle formed by the sensor element 22u and the circumferential direction is an electrical angle of 240 ° (mechanical angle of 60 ° in this embodiment). Moved position). Further, in this embodiment, the shift angle θv of the sensor element 22v and the shift angle θw of the sensor element 22w are set to different angles (θv <θw). In addition, each sensor element 22u, 22v, 22w is arrange | positioned in the position where the distance with respect to the radial direction of the sensor magnet 17 is equal.

  In FIG. 4, the horizontal axis of the graph is an electrical angle (360 °), and the vertical axis of each graph of (a) to (c) is the sensor element 22u (sensor U), sensor element 22v (sensor V), sensor element 22w. Each relationship when the rotation detection signals Ku, Kv, and Kw output from the (sensor W) are shown in the graph.

  The rotation detection signals Ku, Kv, and Kw generated by the sensor elements 22u, 22v, and 22w are signals that become H level when the N pole magnetized portion 17c is detected and become L level when the S pole magnetized portion 17d is detected. is there. In the sensor magnet 17 having different angles θs1, θs2 (θs1> θs2) of the N-pole magnetized portion 17c and the S-pole magnetized portion 17d, rotation detection signals Ku, Kv, Kw output from the sensor elements 22u, 22v, 22w. However, the period (θs1 in the figure) in which the electrical angle is 360 ° for one cycle is longer than the period (θs2 in the figure) in which it is at the L level. On the other hand, the magnetic field of the rotor 3 is changed (the magnetic poles 18 and 19 are switched) at an electrical angle of 180 °. In the sensor element 22u arranged at the reference position, the magnetic pole of the rotor 3 is changed from the N pole 18 to the S. Compared to the timing of switching to the pole 19 (position at an electrical angle of 180 °), the timing at which the rotation detection signal Ku falls from the H level to the L level is delayed by the phase difference of the angle θa.

  Next, the sensor elements 22v and 22w are arranged at positions where phase differences of angles θv and θw are provided from the reference positions where the sensor elements 22v and 22w are arranged corresponding to the V phase and the W phase. . In the sensor elements 22u, 22v, and 22w having such an arrangement, the rotation detection signal Kv output from the sensor element 22v is totally shifted with the rotation of the sensor magnet 17, and the angle θv with respect to the electrical angle of 120 °. It will be delayed by the phase difference. Further, the rotation detection signal Kw output from the sensor element 22w also shifts as a whole, and rises with a delay of the phase difference of the angle θw with respect to the electrical angle of 240 °. In this case, the rotation detection signal Kw rises later because of the relationship θv <θw.

  In the motor M described above, when power is supplied to the winding magnetic pole 10 of the stator 2, the rotor 3 is rotated based on the rotating magnetic field generated by the winding magnetic pole 10. As the rotor 3 rotates, the sensor magnet 17 also rotates. The sensor elements 22u, 22v, and 22w that face the sensor magnet 17 in the axial direction detect a magnetic field in which the magnetized portions 17c and 17d are alternately changed by the rotational operation of the sensor magnet 17, and change the detected magnetic field. The rotation detection signals Ku, Kv, and Kw, which are corresponding pulse signals, are output to the drive control circuit. The drive control circuit supplies power to the winding magnetic poles 10 of each phase using the rising and falling edges of the rotation detection signals Ku, Kv, and Kw as energization timings.

Next, the operation of this embodiment will be described.
In the motor M of the present embodiment, the angle θs1 formed by the N pole magnetized portion 17c of the sensor magnet 17 is set to be larger than the angle θs2 formed by the S pole magnetized portion 17d. Accordingly, the rotation detection signals Ku, Kv, Kw (see FIG. 4) output from the sensor elements 22u, 22v, 22w have a longer period than the period in which the H level is in the L level. Since the motor M uses changes (edges) of the rotation detection signals Ku, Kv, and Kw as energization timings for supplying power to the stator 2, the energization timing for the winding magnetic poles 10 of the stator 2 is the rotor 3. The phase difference of the angle θa is generated with respect to the switching timing of the magnetic poles from the N pole 18 to the S pole 19.

  Here, in the rotor configuration in which the magnetic poles 18 and 19 having the magnet 15 are provided at an equal pitch in the circumferential direction of the rotor core 14 as in the rotor 3 of the present embodiment, the cogging torque accompanying the rotation of the rotor 3 is applied to each magnetic pole. This is a regular generation mode that can occur at the same period and amplitude at the switching timing of 18, 19. Corresponding to this, energization control (calculation) that generates a rotating magnetic field that includes an irregular portion in the magnetic attractive force generated between the stator 2 and the rotor 3 using a control means such as a microcomputer having high processing capability. ), It is conceivable to disperse and reduce each order component included in the torque ripple. However, providing such a control means leads to an increase in cost. Therefore, in the motor M of the present embodiment, the N-pole magnetized portion 17c and the S-pole magnetized portion of the sensor magnet 17 cause the deviation of the angle θa in the energization timing of the stator 2 with respect to the timing at which the magnetic poles 18 and 19 are switched. By setting the angle of the magnetic part 17d, it is possible to generate a rotating magnetic field including an irregular portion in the magnetic attractive force between the stator 2 and the rotor 3 as described above.

  In the magnetic sensor 22 of the present embodiment, the sensor elements 22v and 22w are shifted to positions where the phase differences of the angles θv and θw are provided, and the rotation detection signal Kv output from the sensor element 22v has an electrical angle of 120. The rotation detection signal Kw output from the sensor element 22w rises with a phase difference of the angle θw with respect to the electrical angle of 240 °, and rises with a phase difference of the angle θv with respect to the angle. Will shift. Thereby, it is possible to generate a rotating magnetic field that includes a more irregular portion in the above-described magnetic attractive force.

Next, characteristic effects of the present embodiment will be described.
(1) In this embodiment, with respect to the rotor 3 in which the magnetic poles 18 and 19 having the magnets 15 and 16 are provided at equal pitches in the circumferential direction of the rotor core 14, the sensor magnet 17 is formed by the N-pole magnetized portion 17c. The angle θs1 is set to an angle larger than the angle θs2 formed by the S pole magnetized portion 17d, and the magnetized portions 17c and 17d are provided at unequal pitches in the circumferential direction. The rotation detection signals Ku, Kv, and Kw generated from the sensor elements 22u, 22v, and 22w by the rotation operation of the sensor magnet 17 are longer than the period in which the H level is in the L level. In the energization control for the stator 2, changes (edges) in the rotation detection signals Ku, Kv, Kw are used as the energization timing for the stator 2, so that the energization timing for the winding magnetic pole 10 of the stator 2 A phase difference of an angle θa occurs with respect to the switching timing of the magnetic pole from the N pole 18 to the S pole 19. That is, the rotation detection signals Ku, Kv, and Kw that are shifted with respect to the switching timing of the magnetic poles 18 and 19 of the rotor 3 are output by the configuration in which the magnetized portions 17c and 17d of the sensor magnet 17 are arranged at unequal pitches. The energization timing of the winding magnetic pole 10 of the stator 2 deviates from the switching timing of the magnetic poles 18 and 19 of the rotor 3, and an irregular portion is included in the magnetic attractive force generated between the stator 2 and the rotor 3. A rotating magnetic field can be generated. As a result, calculations that shift the energization timing on the control side are not required, and even with a simple configuration that does not use control means with high processing capacity, each component included in the torque ripple can be dispersed, reducing torque ripple. Can be achieved.

  (2) The motor M of this embodiment has three sensor elements 22u, 22v for generating rotation detection signals Ku, Kv, Kw corresponding to the phases (U phase, V phase, W phase) of the winding magnetic pole 10. , 22w, and sensor elements 22v, 22w are arranged so as to be shifted from the reference positions where the sensor elements 22v, 22w are arranged corresponding to the V phase and the W phase to positions where the phase differences of the angles θv, θw are provided. In other words, the energization timing to the winding magnetic pole 10 of the stator 2 is entirely shifted with respect to the switching timing of the magnetic poles 18 and 19 of the rotor 3 in the phase (V phase / W phase) shifted, and the stator 2 and the rotor 3 It is possible to generate a rotating magnetic field including a more irregular portion in the magnetic attraction force generated therebetween. Thereby, it is possible to further reduce the torque ripple.

  (3) The sensor magnet 17 is configured by alternately arranging the magnetized portions 17c and 17d having different angles θs1 and θs2 in the circumferential direction in the circumferential direction. Thereby, it is possible to easily set one period (electrical angle 360 °) of energization timing to the winding magnetic pole 10 of the stator 2 in each magnetized portion 17c, 17d.

  (4) As detected members used for detecting the rotational position of the rotor 3, N-pole N-pole magnetized portions 17c and S-pole S-pole magnetized portions 17d are alternately arranged in the circumferential direction (rotating direction). An annular sensor magnet 17 is used. Thereby, the member to be detected can be easily configured as an annular sensor magnet 17 in which magnetic poles are magnetized in the circumferential direction.

In addition, you may change embodiment of this invention as follows.
In the above embodiment, the magnetized portions 17c and 17d of the sensor magnet 17 are configured with the radial straight lines as the magnetic pole boundary lines Ls1 to Ls3. However, as shown in FIG. 5, the magnetic pole boundary lines Ls1 to Ls3 May be a straight line inclined at a predetermined angle with respect to a straight line in the radial direction. In this case, the sensor magnet 17 is configured such that the areas of the magnetized portions 17c and 17d viewed from the axial direction of the rotating shaft 11 are the same area. As a result, even if the circumferential lengths of the magnetized portions 17c and 17d at the detection portion of the sensor magnet 17 are different, the areas of the magnetized portions 17c and 17d are the same. The magnetic amounts of 17c and 17d can be made uniform. That is, since the magnetic pole boundary lines Ls1 to Ls3 between the magnetized portions 17c and 17d are more appropriate, errors included in the rotation detection signals Ku, Kv, and Kw can be further reduced. Incidentally, both the magnetized portions 17c and 17d have a rotationally symmetric shape, and can cope with both rotational directions.

  Further, in the sensor magnet 17 of FIG. 5, the magnetic pole boundary lines Ls1 to Ls3 are inclined. Therefore, even when the radial positions of the sensor elements 22u, 22v, and 22w are shifted, the stator 2 is energized. The energization timing to start can be changed.

  In the above embodiment, the sensor magnet 17 is configured by alternately arranging the magnetized portions 17c and 17d having different angles θs1 and θs2 in the circumferential direction in the circumferential direction, but the present invention is not limited to this. For example, the magnetized portions 17c and 17d of the sensor magnet 17 may be changed to a configuration in which at least two sets of the magnetized portions 17c and 17d having different circumferential angles are provided. Accordingly, at least two different energization timings for one cycle (360 °) can be easily set for the winding magnetic poles 10 of each phase by the magnetized portions 17c and 17d, and various energization timings can be set. Thus, it is possible to perform control capable of further reducing torque ripple. Moreover, you may change to the structure from which all the angles which the circumferential direction of each magnetized part 17c, 17d of the sensor magnet 17 makes differ.

  In the above embodiment, the magnetized portions 17c, 17d of the sensor magnet 17 and the sensor elements 22u, 22v, 22w of the magnetic sensor 22 are both arranged at unequal pitches, but only one of them is arranged. May be changed to an unequal pitch. Further, although two of the plurality of sensor elements 22u, 22v, and 22w are shifted from the reference position, for example, one may be shifted.

  In the above embodiment, the configuration / setting of the sensor magnet 17 and the magnetic sensor 22 (each sensor element 22u, 22v, 22w) as the rotation detecting means is an example. For example, the angle θs1 formed by the N-pole magnetized portion 17c May be set to an angle smaller than the angle θs2 formed by the S pole magnetized portion 17d.

  -In the said embodiment, the number of phases of the winding magnetic pole 10 is an example, and you may change it to the structure of a single phase or other multiple phases. Further, the number of sensor elements 22u, 22v, and 22w may be different from the number of phases of the winding magnetic pole 10.

  In the above embodiment, the sensor magnet 17 is used as the member to be detected used for detecting the rotational position of the rotor 3, but the present invention is not limited to this. For example, it may be changed to a magnetic body having a plurality of salient poles (non-magnetized) in the circumferential direction as a detected portion.

  In the above embodiment, the angle and the number of magnetic poles of the magnetic poles of the sensor magnet 17 and the rotor 3 are examples, and may be changed as appropriate. Further, the correspondence relationship between the magnetic poles of the sensor magnet 17 and the rotor 3 is 1: 1, but may be one-to-many (many-to-one).

  In the above embodiment, the rotor 3 is configured as a so-called IPM type in which the magnets 15 and 16 are embedded in the rotor core 14. However, the present invention is not limited to this, and for example, the magnets 15 and 16 are disposed on the outer peripheral surface of the rotor core 14. The so-called SPM type rotor configuration may be changed.

  2 ... Stator, 3 ... Rotor, 10 ... Winding magnetic pole (winding), 14 ... Rotor core, 15, 16 ... Magnet, 17 ... Sensor magnet (detected member, rotation detecting means), 17c ... N magnetized part (first) 1 detected portion, detected portion, rotation detecting means), 17d ... S magnetized portion (second detected portion, detected portion, rotation detecting means), 18 ... N magnetic pole (magnetic pole), 19 ... S magnetic pole (magnetic pole) ), 22 ... Magnetic sensor (detection unit, rotation detection means), 22u, 22v, 22w ... Sensor element (detection unit, rotation detection means), M ... Motor, Ku, Kv, Kw ... Rotation detection signal, θs1, θs2 ... angle.

Claims (5)

A stator that generates a rotating magnetic field by energizing the wound winding;
A rotor disposed opposite to the stator and rotating based on the rotating magnetic field;
A rotation detection means that includes a detection member provided so as to be integrally rotatable with the rotor, and that outputs a rotation detection signal generated by a rotation operation of the detection member;
A motor that performs energization control for generating the rotating magnetic field on the stator based on the rotation detection signal,
The rotor has magnetic poles having magnets provided at equal pitches in the circumferential direction of the rotor core, whereas the detected member of the rotation detecting means has a plurality of detected portions for generating the rotation detection signal in the circumferential direction. Provided at unequal pitches,
Based on the rotation detection signal corresponding to each detected portion of the detected member that rotates together with the rotor, a rotating magnetic field shifted with respect to the switching timing of the magnetic pole of the rotor is generated in the stator. A motor characterized by The motor according to claim 1,
The stator winding is composed of a plurality of phases.
The rotation detection means is provided with a plurality of detection units to generate a rotation detection signal corresponding to each phase of the winding,
At least one of the detection units of each phase is arranged to be shifted from a reference position arranged corresponding to each phase. The motor according to claim 1 or 2,
The detected part of the detected member is configured by alternately arranging a first detected part and a second detected part with different circumferential angles in the circumferential direction. The motor according to claim 1 or 2,
The stator winding is composed of a plurality of phases.
The detected portion of the detected member is provided with at least two combinations of a first detected portion and a second detected portion having different circumferential angles. The motor according to claim 3 or 4,
The detected member of the rotation detecting means has an N-pole magnetized portion as the first detected portion and an S-pole magnetized portion as the second detected portion, and the magnetized portions are alternately arranged in the circumferential direction. A motor characterized by comprising an annular sensor magnet.

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