JP5324248B2 - motor - Google Patents

Description

  The present invention relates to a motor having a rotor partially adopting a contiguous pole type structure.

  Conventionally, as a rotor used in a motor, for example, as shown in FIG. 5 of Patent Document 1, a rotor having an SPM structure in which magnets of both magnetic poles are fixed to an outer peripheral surface of a rotor core, As shown in FIG. 8 of Reference 1, the magnet used from the viewpoint of resource saving, low cost, etc. is halved (single magnetic pole), and it is composed of the magnet and salient poles formed on the rotor core. A rotor having a quantum pole structure is known.

JP 2008-125203 A

  By the way, the present inventor configures a rotor that combines a part (first constituent part) constituted by using magnets of both magnetic poles and a part (second constituent part) constituted by a consequent pole. Are considering. At that time, in the second component composed of the consequent pole, the magnet quantity of the entire rotor is reduced by the amount that the magnet of the other magnetic pole is not used. Is concerned.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to improve torque characteristics in a motor including a rotor partially adopting a consequent pole type structure.

  In order to solve the above problems, the invention described in claim 1 is a motor including a stator in which a coil is wound around a tooth of a stator core, and a rotor in which a magnet is fixed to the rotor core. The rotor includes a first component portion in which N-pole and S-pole magnets are alternately arranged in the circumferential direction, and a magnet on one side of the N-pole and S-pole is axially aligned with the same-pole magnet in the first component portion. A second component part in which magnets on one side arranged side by side and salient poles provided on the rotor core functioning as magnetic poles on the other side are alternately arranged in the circumferential direction. The gist of the invention is that the two constituent parts are arranged so as to be shifted relative to the rotational direction delay side relative to the first constituent part.

  In this invention, the rotor includes a first component having a normal configuration using a bipolar magnet, and a second component of a continuous pole type using only a single-pole magnet and the other pole being a salient pole. The motor is configured such that the second component of the rotor is shifted relative to the rotational direction delay side relative to the first component. Here, in the second component of the continuous pole type, in addition to the magnet torque similar to that of the first component of the normal configuration, reluctance torque is generated at the salient pole, so that the maximum value of the rotational torque advances with respect to the current phase. Appears at Therefore, as described above, the second component is shifted from the first component relative to the rotation direction delay side and the motor is used in a limited rotation direction. The maximum value of the rotational torque and the maximum value of the rotational torque in the second component of the continuous pole type can be brought close to or coincident with each other, and the rotational torque generated by the motor can be increased.

  According to a second aspect of the present invention, in the motor according to the first aspect, the rotor is composed of 10 magnetic poles and the stator is composed of 12 magnetic poles, and the shift angle θ between the first and second constituent parts is The gist is that 0 ° <θ <12 ° is set.

  In the present invention, in the motor in which the rotor has 10 magnetic poles and the stator has 12 magnetic poles, the shift angle θ of the first and second components of the rotor is set to 0 ° <θ <12 °. The generated rotational torque can be increased (see FIG. 5).

  According to a third aspect of the present invention, in the motor according to the second aspect, the shift angle θ of the first and second components is set in a range of 2.5 ° <θ <7.5 °. The gist of this is.

  In this invention, since the shift angle θ of the first and second components of the rotor is set within the range of 2.5 ° <θ <7.5 °, the rotational torque generated by the motor is increased and shifted. Cogging torque, which may be increased by setting the angle θ, can be suppressed (see FIGS. 5 and 6).

  According to a fourth aspect of the present invention, in the motor according to the second aspect, the shift angle θ of the first and second components is set within a range of 5 ± 1 ° or 10 ± 1 °. Is the gist.

  In this invention, since the shift angle θ of the first and second components of the rotor is set within the range of 5 ± 1 ° or 10 ± 1 °, the rotational torque generated by the motor is increased and the shift angle θ With this setting, the cogging torque that is likely to increase can be more sufficiently suppressed (see FIGS. 5 and 6).

The gist of the invention of claim 5 is that, in the motor of claim 2, the shift angle θ of the first and second components is set within a range of 5 ± 1 °. .
In this invention, since the shift angle θ of the first and second components of the rotor is set within a range of 5 ± 1 °, the rotational torque generated by the motor can be increased and the shift angle θ can be set. The cogging torque that is concerned about the increase can be more sufficiently suppressed (see FIGS. 5 and 6).

  According to the present invention, a motor with improved torque characteristics can be provided.

It is radial direction sectional drawing of the brushless motor in this embodiment, (a) is sectional drawing of the 1st structure part, (b) is sectional drawing of the 2nd structure part. It is an axial sectional view of the motor. It is a perspective view of the rotor of the motor. It is a waveform diagram showing the relationship between the current phase and the rotational torque of the first and second components of the rotor, (a) is a waveform diagram of the first component, (b) is a waveform diagram of the second component, (C) is a wave form diagram which overlaps and shows the waveform at the time of making the magnetic pole of the 1st and 2nd composition part correspond. It is explanatory drawing for demonstrating the suitable relative shift angle of the 1st, 2nd component part of a rotor regarding rotational torque. It is explanatory drawing for demonstrating the suitable relative shift angle of the 1st, 2nd structure part of a rotor regarding a cogging torque.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
1A, 1B, and 2 show a brushless motor 10 of the present embodiment. 2 shows a cross section in the axial direction of the motor, FIG. 1 (a) is a cross-sectional view taken along the line AA in FIG. 2, and FIG. 1 (b) is a cross-sectional view taken along the line BB in FIG.

The brushless motor 10 of the present embodiment is configured by an inner rotor type brushless motor in which a rotor 21 is rotatably disposed inside an annular stator 11.
As the stator 11, an annular stator core 12 is used in which twelve teeth 12a having the same shape extending inward in the radial direction are provided at equal angular intervals in the circumferential direction. The stator core 12 is composed of a laminated core configured by laminating a plurality of magnetic metal plates in the axial direction. Each of the teeth 12a of the stator core 12 is individually wound with concentrated coils. In this case, three-phase coils 13u1 to 13u4, 13v1 to 13v4, 13w1 to 13w4 of U, V, and W phases are respectively provided at predetermined positions. The number of magnetic poles wound around the stator 11 is set to “12”.

  About the winding aspect of the coil, in this embodiment, each phase has four coils 13u1 to 13u4, 13v1 to 13v4, 13w1 to 13w4 in total, and U phase so that two of the same phase are adjacent to each other. It is wound in the order of V phase, W phase, U phase, V phase, and W phase. The coil winding direction is reversed between adjacent in-phases, and the coil winding direction is also reversed between the 180 ° facing positions.

  The stator 11 is inserted into the inner peripheral surface of a bottomed cylindrical housing 15 having an open shape at one end from the open portion 15a and is fixed by press-fitting or shrink fitting. The housing 15 may be configured as a part of the magnetic circuit, or may be configured not to be included in the magnetic circuit. A disc-shaped end frame 16 is attached to the open portion 15 a of the housing 15, and the open portion 15 a of the housing 15 is closed by the end frame 16. Bearings 17 and 18 for rotatably supporting the rotating shaft 26 of the rotor 21 are provided at the center of the bottom 15b of the housing 15 and the center of the end frame 16, respectively.

  The rotor 21 is configured by combining two configurations of the first component 21A and the second component 21B in the axial direction and being fixed to the rotary shaft 26. 21 A of 1st structure parts are arrange | positioned in the axial direction one side in the location where the stator core 12 opposes 1/2 of the axial direction length of the said stator core 12, and 2nd structure part whose axial direction length is also 1/2 21B is arranged on the other side in the axial direction at the opposed portion of the stator core 12 so as to be continuous with the first component 21A.

  The first component 21 </ b> A has a cylindrical rotor core 22 formed by laminating a plurality of magnetic metal plate materials, and the rotor core 22 is press-fitted and fixed to a rotating shaft 26. A total of 10 magnets 23n and 23s of N poles and S poles are fixed to the outer peripheral surface of the rotor core 22 so that the magnetic poles alternate in the circumferential direction (SPM structure), and the number of magnetic poles in the first component 21A Is configured as “10”. The magnets 23n and 23s have a rectangular shape when viewed in the radial direction and an arc shape with a constant thickness in the circumferential direction when viewed in the axial direction, and are arranged side by side at equal angular intervals of 36 °. As the magnets 23n and 23s, radial oriented magnets that are magnetized in the radial direction are used.

  The second component 21B is formed by laminating a plurality of magnetic metal plate materials, and a substantially cylindrical rotor core 24 having five salient poles 24a at equal angular intervals of 72 ° is used. The rotor core 22 is integrally connected to the rotor core 22 with the same axial length as the rotor core 22 and is press-fitted and fixed to the rotary shaft 26 together. The salient poles 24a formed integrally with the rotor core 24 have the same shape as the magnets 23n (23s, 25n). The salient pole 24a is provided so as to be aligned with the S pole magnet 23s of the first component 21A in the axial direction.

  In the recesses between the salient poles 24a of the rotor core 22, a total of five magnets 25n (only the magnet 23n can be integrated) having only N poles are fixed, and in this case, they are fixed at equal angular intervals of 72 °. ing. The magnet 25n has the same shape as the magnets 23n and 23s, and the same radial orientation magnet is used. Also in the second component 21B, the number of magnetic poles is “5” by the N-pole magnet 25n, and the number of magnetic poles is “5” by the salient pole 24a (so-called contiguous pole) that eventually becomes the S-pole. 10 "magnetic poles are constructed.

  By the way, the motor 10 of the present embodiment is configured for an application in which the rotational direction of the rotor 21 is used as one direction. As shown in FIGS. 1 and 3, the second component 21 </ b> B of the rotor 21 is configured as follows. The first component 21A is disposed so as to be shifted relative to the rotational direction delay side by a predetermined angle (relative shift angle) θ relative to the first component 21A. That is, the N pole magnet 25n and the salient pole 24a of the second component 21B are relatively delayed in the rotation direction of the respective magnetic pole centers than the N pole magnet 23n and the S pole magnet 23s of the first component 21A, respectively. It is shifted to the side.

  Here, FIG. 4A shows a waveform of the rotational torque of the first component 21A having the normal configuration, and FIG. 4B shows a waveform of the rotational torque of the second component 21B having the continuous pole type. . FIG. 4C shows the waveforms of the respective rotational torques when the magnetic poles of the first and second components 21A and 21B are made coincident with each other.

  As shown in FIG. 4A, the first component 21A alone does not cause a phase shift between the current phase of the coil supply current and the rotational torque. On the other hand, as shown in FIG. 4B, the second component 21B alone does not cause a phase shift between the current phase of the coil supply current and the rotational torque (the dashed line in the figure) of the magnet 25n. In addition to the magnet torque generated by the action of the magnet 25n, reluctance torque (two-dot chain line) is generated in the pole 24a. As a result, the rotation of the second component 21B alone generated with respect to the current phase of the coil supply current Torque (solid line in the figure) appears at a position where the maximum value has advanced (position shifted in the direction of rotation). In other words, as shown in FIG. 4C, when the magnetic poles of the first and second component parts 21A and 21B are made to coincide with each other, the maximum values of the respective rotational torques generated in the component parts 21A and 21B are obtained. Since deviation occurs, waste occurs during synthesis, and the maximum value of the combined rotational torque (not shown) is slightly reduced.

  FIG. 5 shows the relationship between the relative shift angle θ (electrical angle) of the first and second components 21A and 21B and the rotational torque. As shown in FIG. 5, the combined rotational torque shows the maximum value when the relative shift angle θ is around 5 °, and gradually decreases before and after the relative shift angle θ from 5 °. If the combined rotational torque when the relative shift angle θ is 0 ° is “1”, the relative shift angle θ is larger than “1” in the range of 0 ° <θ <12 °, and the combined rotational torque increases. I understand that As shown in FIG. 4C, this is because the rotational torque of the second component 21B advances relative to the first component 21A, and the second component 21B relative to the first component 21A. This is because the maximum values of the rotational torques of the constituent portions 21A and 21B come close to or coincide with each other by shifting them to the delay side.

  Further, FIG. 6 shows the relationship between the relative shift angle θ (electrical angle) of the first and second components 21A and 21B and the cogging torque. As shown in FIG. 6, the cogging torque changes in a sinusoidal shape such that the cogging torque has a maximum value at a multiple of about 2.5 ° and a minimum value at a multiple of about 5 ° with respect to the relative shift angle θ. doing. As shown in FIG. 6, when the relative shift angle θ is in the range of 2.5 ° <θ <7.5 °, the above-described combined rotational torque is large and the cogging torque is smaller than the maximum value. In addition, when the relative shift angle θ is within a range α1 of 4 to 6 ° (5 ± 1 °) and within a range α2 of 9 to 11 ° (10 ± 1 °), the combined rotational torque is large and the cogging torque is large. This is a preferable range that is about half or less of the maximum value. In particular, the combined rotational torque has a maximum value in the vicinity of 5 °. Therefore, it is more preferable to set the relative shift angle θ within the range α1 of 4 to 6 ° (5 ± 1 °) because the increase in cogging torque can be suppressed. The range.

  Accordingly, in the rotor 21 used in the present embodiment, the relative shift angle θ of the first and second components 21A and 21B is set to any angle within the range α1 of 4 to 6 ° (5 ± 1 °). Further, the configuration is such that the cogging torque, which is likely to increase when the rotational torque is increased and the relative shift angle θ is set, is more sufficiently suppressed.

Next, characteristic effects of the present embodiment will be described.
(1) In this embodiment, the rotor 21 includes a first component 21A having a normal configuration that uses magnets 23n and 23s of both poles, and a continuity that uses only a single-pole magnet 25n and the other poles are salient poles 24a. The motor 10 includes a second component 21B of a Quant Pole type, and the motor 10 is configured such that the second component 21B of the rotor 21 is shifted relative to the rotation direction delay side relative to the first component 21A. Has been. That is, in the continuous pole type second component 21B, in addition to the magnet torque similar to the first component 21A having the normal configuration, the reluctance torque is generated at the salient pole 24a, so that the maximum value of the rotational torque is changed to the current phase. The second component 21B is arranged so as to be relatively shifted from the first component 21A toward the rotation direction delay side, and in this embodiment, the shift angle θ is 5 ±. It is set to any one within the range α1 of 1 °. As a result, by using the motor 10 with the rotation direction limited, the maximum value of the rotation torque in each of the components 21A and 21B can be substantially matched, and the combined rotation torque (rotation torque generated by the motor 10) can be further increased. In addition, the cogging torque, which is likely to increase when the shift angle θ is set, can be sufficiently suppressed to about half or less of the maximum value (see FIGS. 5 and 6).

In addition, you may change embodiment of this invention as follows.
In the above embodiment, the shift angle θ of the first and second components 21A and 21B of the rotor 21 is set within the range of 4 to 6 ° (5 ± 1 °). A certain angle, for example, 0 ° <θ <12 °, 2.5 ° <θ <7.5 °, θ = 9 to 11 ° (10 ± 1 °), etc. Good.

  In the above embodiment, the rotor 21 is configured by the first and second components 21A and 21B one by one. However, at least one of the rotors may be divided into two or more, and may be combined appropriately. Moreover, when the 2nd structure part 21B is made into 2 or more division | segmentation, the magnetic pole of the magnet to be used may be changed suitably instead of making it the same magnetic pole.

  In the magnets 23n, 23s, and 25n of the above embodiment, a magnetic separation portion made of, for example, a gap or a nonmagnetic material may be provided between the first and second constituent portions 21A and 21B. In this way, it is possible to reduce the leakage flux from the magnet 23s of the first component 21A to the salient pole 24a of the second component 21B.

  In the above-described embodiment, the rotor cores 22 and 24 and the stator core 12 are configured by stacking magnetic metal plate materials. However, the core is not limited to such a stacked core but may be configured by molding magnetic powder, for example. Good.

  In the above embodiment, the number of magnetic poles on the stator 11 side is “12” and the number of magnetic poles on the rotor 21 side is “10”, but the number of magnetic poles on the stator 11 side and the number of magnetic poles on the rotor 21 side are appropriately set. A modified configuration may be used.

  DESCRIPTION OF SYMBOLS 10 ... Brushless motor (motor), 12 ... Stator core, 12a ... Teeth, 13u1-13u4, 13v1-13v4, 13w1-13w4 ... Coil, 21 ... Rotor, 21A ... 1st structure part, 21B ... 2nd structure part, 22, 24 ... rotor core, 23n, 23s, 25n ... magnet, 24a ... salient pole.

Claims (5)

A motor including a stator in which a coil is wound around teeth of a stator core and a rotor in which a magnet is fixed to the rotor core;
The rotor is
A first component in which N-pole and S-pole magnets are alternately arranged in the circumferential direction;
A magnet provided on one side of the N-pole and the S-pole is provided on the rotor core that functions as a magnet on the one side, which is arranged side by side in the axial direction with the magnet on the same pole of the first component. And a second component portion alternately arranged in the circumferential direction with poles,
The motor is characterized in that the second component of the rotor is arranged so as to be relatively shifted from the first component toward the rotational direction delay side. The motor according to claim 1,
The rotor is composed of 10 magnetic poles, and the stator is composed of 12 magnetic poles,
The motor is characterized in that the shift angle θ of the first and second components is set to 0 ° <θ <12 °. The motor according to claim 2,
The motor is characterized in that the shift angle θ of the first and second components is set in a range of 2.5 ° <θ <7.5 °. The motor according to claim 2,
The motor characterized in that the shift angle θ of the first and second components is set within a range of 5 ± 1 ° or 10 ± 1 °. The motor according to claim 2,
The motor characterized in that the shift angle θ of the first and second components is set in a range of 5 ± 1 °.

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