JP5290726B2 - motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor that reduces vibration while properly configuring a rotor and a housing. <P>SOLUTION: A rotor 21 includes a first configuration part 21A of a normal configuration using a double-pole magnet, and a consequent-pole type second configuration part 21B using only a single-pole magnet while configuring the other pole of a salient pole of a rotor core. A motor 10 is configured by arranging the second configuration part 21B of the rotor 21 closer to the side of an opening part 15a of a housing 15 than the first configuration part 21A. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

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

  For example, as shown in FIG. 5 of Patent Document 1, the rotor of the motor is a rotor composed only of magnetic poles of a magnet, or as shown in FIG. A rotor or the like composed of a magnetic pole magnet and salient poles (concrete poles) formed on a rotor core is used.

On the other hand, in a motor stator, an annular stator core around which a coil is wound is fixed to an inner surface of a cylindrical housing. At this time, since the stator core is generally fixed to the housing by press-fitting or shrink-fitting, one having one end or both ends of the housing being open is often used. An end frame is attached to the open portion of the housing, and the open portion is closed by the end frame.
JP 2008-125203 A

  By the way, the present inventor configures one rotor in which a part (first constituent part) constituted only by magnetic poles of a magnet and a part (second constituent part) constituted by a continuous pole are mixed. Are considering. At that time, since the magnetic forces of the first component and the second component are different, the radial force acting on the stator core due to the attractive repulsion force with the magnet of the rotor is different between the first component and the second component. become. That is, the radial force acting on the stator core during the rotation of the rotor is non-uniform in the circumferential direction, which leads to vibration of the housing, so that there is a difference in the radial force between the first component and the second component. And the magnitude of vibration varies depending on the housing part. In addition, since the open portion of the housing to which the end frame is mounted has low rigidity, if a large radial force is applied to the stator core in the vicinity of the open portion, the housing is greatly deformed and vibration is increased.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a motor capable of reducing the vibration by making the configurations of the rotor and the housing suitable.

In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that a rotor having a magnet fixed to a rotor core is rotatably accommodated inside an annular stator core in which a coil is wound around a tooth, and at least one end is accommodated. A motor in which the stator core is fixed to an inner surface of a cylindrical housing having an open side, and an open portion of the housing is closed by an end frame, and the rotor includes an N pole and an S pole The first component in which the magnets are alternately arranged in the circumferential direction and the magnet on one side of the N pole and the S pole are arranged side by side with the magnet of the same pole in the first component in the axial direction. comprising of a magnet, and a second component which is a salient pole provided in the core which acts as the magnetic pole on the other side are arranged alternately in the circumferential direction, the radial force acting on said stator core Serial has become smaller towards the second component than the first component, that is formed by arranging the open side of the housing than the second component the first component of the rotor The gist.

  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 arranged closer to the open portion of the housing than the first component. Here, since the second component portion uses less magnets than the first component portion and has a smaller magnetic force, the radial force acting on the stator core due to the opposing components of the rotor is smaller than the first component portion. The component is smaller. Based on this, the second component part having a small radial force is arranged on the opening part side having a low rigidity of the housing, and the first component part having a large radial force is arranged on a part having a high rigidity apart from the opening part. In addition, each component is rationally arranged based on the rigidity of the housing, and deformation of the housing due to the radial force is suitably suppressed. Thereby, the vibration of the housing due to the radial force acting on the stator core is suppressed, and the vibration of the motor can be further reduced.

  According to a second aspect of the present invention, in the motor according to the first aspect, the housing has a bottomed cylindrical shape with one end open, and an open portion at one end is closed by the end frame. The first and second components of the rotor are arranged one by one in the axial direction, and the second component is arranged closer to the open portion of the housing than the first component. The gist of this is

  In this invention, the housing has a bottomed cylindrical shape with one open end, and the open portion at one end is closed by the end frame, whereas the first and second constituent portions of the rotor are each one. They are arranged side by side in the axial direction, and the second component is arranged closer to the open portion of the housing than the first component. As a result, the vibration of the motor can be reduced by suppressing the vibration of the housing while facilitating manufacture with a simple structure of the rotor.

  According to a third aspect of the present invention, in the motor according to the first aspect, the housing has a cylindrical shape with both ends open, and open portions at both ends are respectively closed by the end frame. The second component part of the rotor is divided into two parts and arranged on both sides in the axial direction of the first component part, and is arranged closer to the open part of the housing than the first component part. The gist.

  According to the present invention, the housing has a cylindrical shape whose both ends are open and the open portions at both ends are respectively closed by the end frame. On the other hand, the second component of the rotor is divided into two parts. Are disposed on both sides in the axial direction of the housing, and are disposed closer to the open portion of the housing than the first component. Thereby, the vibration of the motor can be reduced by suppressing the vibration of the housing while facilitating the manufacture by simplifying the structure of the housing by making the both ends open cylindrical.

  According to the present invention, each configuration of the rotor and the housing is suitable, and a motor capable of reducing vibration can be provided.

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 ten 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 are alternately arranged in the circumferential direction. The number of magnetic poles in the first component 21A is “10”. It is configured as. 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 having only N poles are fixed, and in this case, are fixed at equal angular intervals of 72 °. The magnet 25n has the same shape as the magnets 23n and 23s, and the same radial orientation magnet is used. The N-pole magnet 25n is provided so as to be aligned in the axial direction with the N-pole magnet 23n of the first component 21A. 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 continuous pole) that eventually becomes the S-pole. A total of “10” magnetic poles are formed.

  Here, FIG. 3 shows the cogging torque generated in the first component 21A having the normal configuration having the magnets 23n and 23s of both poles and the second component 21B having the continuous pole type having the magnet 25n having only one pole. The waveform is shown.

  As shown in FIG. 3, the pulsation of the cogging torque generated in the second component 21B of the continuous pole type is 180 ° in electrical angle with respect to the pulsation of the cogging torque generated in the first component 21A having the normal configuration. Since the phase is shifted, that is, in the opposite phase, in the rotor 21 of this embodiment having both the components 21A and 21B, the cogging torque pulsations cancel each other. That is, the pulsation of the combined cogging torque is extremely small, and in the brushless motor 10 of this embodiment using this rotor 21, vibration during rotational driving is reduced.

  FIG. 4 shows the radial force acting on the stator core 12 by the suction repulsive force with the rotor 21. The radial force is shown corresponding to the circumferential position of the stator core 12, and the magnitude of the radial force increases toward the outer side in the radial direction. The radial force acting on the stator core 12 deforms the housing 15 to induce vibration.

  As in the present embodiment, the first component 21A having the normal configuration using the magnets 23n and 23s and the second component 21B having the continuous pole type using only the magnet 25n have different magnetic forces, and thus act on the stator core 12. The radial force of the second component 21B having a smaller magnetic force is smaller than that of the first component 21A. The radial force acting on the stator core 12 when the rotor 21 rotates is non-uniform in the circumferential direction, which causes the stator core 12 to vibrate and consequently the housing 15 to vibrate.

  Considering this, the motor 10 of the present embodiment is configured such that the second component 21B of the rotor 21 is disposed closer to the open portion 15a of the housing 15 than the first component 21A. That is, the second component 21B having a small radial force is arranged on the opening portion 15a side of the housing 15 having a low rigidity, and the first component portion 21A having a large radial force is arranged on the bottom portion 15b side of the housing 15 having a high rigidity. In addition, in the present embodiment, rational arrangement of the constituent portions 21A and 21B based on the rigidity of the housing 15 is adopted, and deformation of the housing 15 is suitably suppressed. Thereby, the vibration of the housing 15 is suppressed, and the vibration of the brushless motor 10 is further reduced in combination with the reduction of the cogging torque.

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 disposed closer to the opening 15a of the housing 15 than the first component 21A. Yes. That is, since the second component 21B uses less magnet for the first component 21A and has a smaller magnetic force, the radial force acting on the stator core 12 due to the opposing of the components 21A and 21B of the rotor 21 is the first. The second component 21B is smaller than the component 21A. Based on this, the second component 21B having a small radial force is disposed on the opening 15a side of the housing 15 having a low rigidity, and the first component 21A having a large radial force is disposed on the bottom 15b side of the housing 15 having a high rigidity. As described above, the components 21A and 21B are rationally arranged based on the rigidity of the housing 15, and the deformation of the housing 15 due to the radial force is suitably suppressed. Thereby, the vibration of the housing 15 resulting from the radial force acting on the stator core 12 is suppressed, and the vibration of the motor 10 can be further reduced. In addition, since members necessary for vibration suppression can be eliminated or the rotor 21 and the stator 11 can be configured close to the open portion 15a of the housing 15, the number of components can be reduced and the housing 15 can be reduced in size.

  (2) In the present embodiment, the housing 15 has a bottomed cylindrical shape with one open end, and the open portion 15 a at one end is closed by the end frame 16. The component parts 21A and 21B are arranged one by one in the axial direction, and the second component part 21B is arranged closer to the open part 15a of the housing 15 than the first component part 21A. Thereby, the vibration of the motor 10 can be reduced by suppressing the vibration of the housing 15 while simplifying the structure of the rotor 21 and facilitating manufacture.

In addition, you may change embodiment of this invention as follows.
In the above-described embodiment, the bottomed cylindrical housing 15 is used, and the first and second components 21A and 21B of the rotor 21 that are arranged in parallel in the axial direction are respectively provided on the second component 21B side. However, the combination of the configuration of the rotor 21 and the housing 15 is not limited to this.

  For example, as shown in FIG. 5, the housing 15 has a cylindrical shape with both ends open, and the open portions 15 a at both ends are closed by end frames 16. On the other hand, the second component 21B of the rotor 21 is divided into two parts and disposed on both sides in the axial direction of the first component 21A, and is disposed closer to the opening 15a of the housing 15 than the first component 21A. Yes. That is, each second component 21B having a small radial force is disposed on the opening portion 15a side of the housing 15 having a low rigidity, and the first component portion 21A having a large radial force is separated from the opening portion 15a of the housing 15 by a rigidity. It is considered to be a reasonable arrangement placed in the high central part. Thereby, the vibration of the housing 15 resulting from the radial force acting on the stator core 12 is suppressed, and the vibration of the motor 10 can be further reduced. In addition, since the both ends are formed into a cylindrical shape, the configuration of the housing 15 is simplified, and the manufacture of the housing 15 is facilitated.

  Incidentally, the magnets of the second component 21B divided into two parts may be N poles or S poles and may be configured with the same poles. The second component 21B divided into two parts may be configured using magnets having different magnetic poles for each division, and in this case, the magnetic balance of the second component 21B is good.

  In the above embodiment, the magnets 23n, 23s, and 25n in the first and second components 21A and 21B are not particularly mentioned, but may be formed separately between the components 21A and 21B. In this way, the size (axial length, etc.) of the magnets 23n, 23s, 25n between the first and second components 21A, 21B can be easily adjusted.

  In this case, 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, the leakage magnetic flux from the magnet 23s of the first component 21A to the salient pole 24a of the second component 21B is reduced.

  Further, the magnets 23n and 25n having the same polarity in the first and second components 21A and 21B may be integrally formed across the components 21A and 21B. In this case, the rotor 21 can be configured with a small number of parts.

  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.

Next, a technical idea that can be grasped from the above embodiment and another example will be added below.
(A) In the motor according to any one of claims 1 to 3,
The motor is characterized in that the second component part is divided into two parts, and a magnet having a different magnetic pole is used for each division.

In this configuration, since the second component divided into two parts is configured using magnets having different magnetic poles for each division, the magnetic balance of the second component is improved.
(B) In the motor according to any one of claims 1 to 3 and (a) above,
The motor according to claim 1, wherein the magnets in the first and second components are divided between the components.

  In this configuration, since the magnets in the first and second components are formed separately between the components, the magnet size (axial length, etc.) between the components can be easily adjusted. it can. Further, if a magnetic separation portion is provided between the first and second components, magnetic flux leakage from the magnet of the first component to the salient pole of the second component is reduced.

(C) In the motor according to any one of claims 1 to 3 and (a) above,
The motor having the same polarity in the first and second components is formed integrally with each component.

  In this configuration, the magnets having the same polarity in the first and second components are integrally formed beyond the components, so that the rotor can be configured with a small number of parts.

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 brushless motor. It is a wave form diagram which shows the cogging torque of the same brushless motor. It is explanatory drawing for demonstrating the radial force which acts on the stator core of the same brushless motor. It is an axial sectional view of a brushless motor in another example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Brushless motor (motor), 12 ... Stator core, 12a ... Teeth, 13u1-13u4, 13v1-13v4, 13w1-13w4 ... Coil, 15 ... Housing, 15a ... Opening part, 16 ... End frame, 21 ... Rotor, 21A ... 1st component, 21B ... 2nd component, 22, 24 ... rotor core, 23n, 23s, 25n ... magnet, 24a ... salient pole.

Claims (3)

A rotor with a magnet fixed to the rotor core is rotatably accommodated inside an annular stator core with a coil wound around the teeth, and the stator core is fixed to the inner surface of a cylindrical housing having an open shape at least on one end side. A motor configured by closing an open portion of the housing with an end frame,
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 part alternately arranged in the circumferential direction, the radial force acting on the stator core is smaller in the second component part than the first component part ,
2. The motor according to claim 1, wherein the second component part of the rotor is arranged closer to the open part of the housing than the first component part. The motor according to claim 1,
The housing has a bottomed cylindrical shape with one open end, and an open portion at one end is closed by the end frame,
The first and second components of the rotor are arranged one by one in the axial direction, and the second component is arranged closer to the open portion of the housing than the first component. A motor characterized by The motor according to claim 1,
The housing has a cylindrical shape with open ends, and open portions at both ends are respectively closed by the end frame,
The second component part of the rotor is divided into two parts and arranged on both sides in the axial direction of the first component part, and is arranged closer to the open part of the housing than the first component part. motor.

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