JP2009124852A - Rotor for rotary electric machine, and rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotor for a rotary electric machine capable of achieving easy manufacture as well as high torque by tilting the orientation of magnets relative to a diametrical direction, and to provide the rotary electric machine with the rotor. <P>SOLUTION: The magnets having magnetic poles different from each other in a peripheral direction are polarized so that a radial magnetic flux passing through one point on a center line of the magnetic pole set on the outer-peripheral side of the respective magnetic poles is generated. At the same time, a ratio (R/r) of a distance R from an axial line of a rotating shaft to the one point on the center line of the magnetic pole to a distance r from the axial line of the rotating shaft to a surface (an outer-peripheral surface) of the magnet is set to ≥1.1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rotor of a rotating electrical machine and a rotating electrical machine.

2. Description of the Related Art Conventionally, an inner rotor of a rotating electrical machine includes a magnet having a radial shape such that a magnetic field orientation narrows radially outward in a cross section orthogonal to the axis of the rotation axis (see, for example, Patent Document 1). In such a rotor, a strong magnetic field is generated by increasing the magnetic flux density on the magnet surface facing the stator, and as a result, the torque output of the rotating electrical machine is improved.
JP 2005-253146 A

  However, in the rotor as described above, when one point (convergence point) connecting the radial orientation directions in the magnet is close to the magnet surface, that is, when the inclination with respect to the radial direction of the orientation is large, a large torque improvement effect can be obtained. There is a problem that the magnetization becomes more difficult as the orientation gradient of the magnet is increased, and there is still room for improvement in this respect.

  The present invention has been made to solve the above-described problems, and its object is to provide a rotating electrical machine that can be easily manufactured while increasing the torque by inclining the orientation of the magnet with respect to the radial direction. And providing a rotating electric machine including the rotor.

  In order to solve the above problem, the invention according to claim 1 is a rotor of a rotating electrical machine in which magnets having different magnetic pole arrangements alternately in a circumferential direction are provided on a rotary shaft so as to be integrally rotatable, The magnet is magnetized so that a radial magnetic flux passing through one point on the magnetic pole center line set on the outer circumferential side of each magnetic pole is generated, and the distance R from the axis of the rotating shaft to one point on the magnetic pole center line, The gist is that the ratio value (R / r) to the distance r from the axis of the rotation axis to the surface of the magnet is set to 1.1 or more.

  In the present invention, magnets having different magnetic pole arrangements alternately in the circumferential direction are magnetized so that a radial magnetic flux passing through one point on the magnetic pole center line set on the outer circumferential side of each magnetic pole is generated, and the axis of the rotating shaft The ratio value (R / r) between the distance R from the center of the magnetic pole to one point on the magnetic pole center line and the distance r from the axis of the rotation axis to the surface of the magnet is set to 1.1 or more. Here, from the relational diagram showing the relationship between the value of the ratio of the distances R and r (radial orientation center position) and the torque (see FIG. 4), the rotation axis is within the range where the value of R / r is 1.1 or more. When a point on the magnetic pole center line does not approach from the axis of the magnet and the surface of the magnet, that is, the orientation is along the radial direction while preventing the orientation gradient of the magnet from increasing (the torque ratio is “1” in FIG. 4). Greater torque can be obtained. Thereby, it becomes possible to manufacture easily while making the orientation of the magnet inclined with respect to the radial direction and improving the torque output of the rotating electrical machine.

According to a second aspect of the present invention, in the rotor of the rotating electric machine according to the first aspect, a ratio value (R / r) of the distances R and r is set to 1.1 or more and 1.6 or less. This is the gist.
In the present invention, the ratio value (R / r) of the distances R and r is set to 1.1 or more and 1.6 or less. For this reason, while producing easily, when the value of R / r is 1, that is, when the orientation of the magnet is maximum and the production is most difficult, a larger torque output can be obtained (see FIG. 4). .

According to a third aspect of the present invention, in the rotor of the rotating electric machine according to the second aspect, a ratio value (R / r) of the distances R and r is set to 1.1 or more and 1.2 or less. This is the gist.
In the present invention, the ratio value (R / r) of the distances R and r is set to 1.1 or more and 1.2 or less, so that it is even higher in the range of 1.1 or more and 1.6 or less. Can contribute to torque.

  According to a fourth aspect of the present invention, there is provided the rotor according to any one of the first to third aspects, and a winding that is provided around the rotor and that generates a magnetic field for rotating the rotor. The gist of the present invention is that the rotating electrical machine includes a stator.

  In this invention, the rotor according to any one of claims 1 to 3 is provided inside the stator to constitute a rotating electrical machine. Therefore, it is possible to provide a rotating electrical machine that can be easily manufactured while increasing the torque by inclining the orientation of the magnet with respect to the radial direction.

  Therefore, according to the above-described invention, there is provided a rotor of a rotating electrical machine that can be easily manufactured while increasing the torque by inclining the orientation of the magnet with respect to the radial direction, and a rotating electrical machine including the rotor. can do.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
As shown in FIG. 1, a brushless motor (hereinafter referred to as a motor) 1 as a rotating electrical machine includes a stator 2 and a rotor 3. The stator 2 is formed in a substantially cylindrical shape, and includes twelve teeth 4 extending radially inward, and windings 5 wound around the teeth 4. The stator 2 is configured to generate a rotating magnetic field for rotating the rotor 3 when power from a power supply device (not shown) is supplied to the winding 5.

  The rotor 3 rotatably supported inside the stator 2 includes a rotating shaft 6, a substantially cylindrical rotor core 7 fixed to the rotating shaft 6, and ten magnets 8 a fixed to the outer peripheral surface of the rotor core 7. 8b. Each of the magnets 8a and 8b has an arc shape and is formed in the same shape, and the magnetic flux direction (arrow in the magnet) faces the outside and the outer peripheral surface is an N pole, and the magnetic flux direction is the inner circumference. The magnets 8b facing the side and having an S-pole outer peripheral surface are alternately arranged in the circumferential direction (see FIG. 2). The magnets 8a and 8b are in contact with each other in the circumferential direction.

  As shown in FIG. 2, the magnets 8 a and 8 b are arranged in the cross section orthogonal to the axis L of the rotating shaft 6, and the magnetic pole center line CL (the center in the circumferential direction of each magnet 8 a and 8 b is along the rotor radial direction). The magnetic flux which inclines so that it may approach the (line which passes through) is produced. In other words, the magnets 8a and 8b are configured to generate a radial magnetic flux that passes through one point P on the magnetic pole center line CL disposed on the outside thereof. Note that a magnetic flux along the radial direction (magnetic pole center line CL) is generated at the circumferential center of the magnets 8a and 8b.

A manufacturing mode of such magnets 8a and 8b will be described with reference to FIG.
As shown in FIG. 3, the magnet 8 a is sandwiched between a pair of iron cores 11 and 12 of a so-called magnetizer during its manufacture. Coils (not shown) are wound around the pair of iron cores 11 and 12, respectively. One iron core 11 is in contact with the entire inner peripheral surface of the magnet 8a, and the other iron core 12 is outside the magnet 8a. And extending along a straight line (corresponding to the magnetic pole center line CL) that bisects the circumferential direction. And, by energizing the coils wound around the iron cores 11 and 12, the iron cores 11 and 12 are radially passing through one point (matching the point P) on the straight line (CL) arranged outside the magnet 8a. The magnet 8a is magnetized in a radial orientation centered on the point P arranged outside as described above. Magnetization of the magnet 8b is performed in substantially the same manner except that the polarity of the magnetic flux generated in each of the iron cores 11 and 12 is reversed, and the description thereof is omitted. When magnetizing such a point P on the outside, as the point P is set at a position farther from the outer peripheral surface of the magnets 8a and 8b, the orientation inclination of the magnets 8a and 8b becomes gentler and can be easily magnetized. It has become.

  In the rotor 3 as described above, the distance from the axis L of the rotating shaft 6 to one point P on the magnetic pole center line CL is the distance R, and the distance from the axis L to the outer surface (outer peripheral surface) of the magnets 8a and 8b is the distance. Assuming r, the ratio value (R / r) of these distances R and r representing the radial orientation center position (point P) of the magnets 8a and 8b is set to “1.125”.

  Here, as shown in FIG. 4, the inventor examined the torque characteristics with respect to the ratio value (R / r) of the distances R and r. Note that the torque when the magnets 8a and 8b are oriented in the radial direction under the condition of the same shape (the distance r from the axis L to the outer peripheral surfaces of the magnets 8a and 8b is constant) is “1”.

  As is clear from FIG. 4, if the ratio value (R / r) of the distances R and r is 1 or more, the torque ratio is maintained at about 1.3 or more, and a high torque can be expected. It is confirmed. In this range, the value of R / r does not decrease, that is, the range of “1.1” or more that does not include the range in which the orientation inclination of the magnets 8a and 8b does not increase is extremely easy to magnetize the magnets 8a and 8b. Is advantageous. In addition, when the value of R / r is in the range of “1.6” or less within the range of “1.1” or more, the value of R / r at which the orientation gradient is maximum and magnetization is most difficult is When “1”, a torque higher than that can be obtained. The value of R / r in this embodiment is almost the maximum in the range of 1.1 to 1.2 in which the remarkable torque improvement effect can be expected, among the range of 1.1 to 1.6. Is set to “1.125”.

  5 shows the surface magnetic flux density of the rotor 3 (indicated by the solid line in FIG. 5) when the ratio value (R / r) of the distances R and r is “1.125”, and the magnets 8a, 8a, A comparison is made with the surface magnetic flux density (indicated by a two-dot chain line in FIG. 5) of the rotor when 8b is oriented in the radial direction. As shown in FIG. 5, the surface magnetic flux density of the rotor 3 when the ratio value (R / r) of the distances R and r is “1.125” is obtained when the magnets 8a and 8b are oriented in the radial direction. It is higher than the surface magnetic flux density of the rotor. That is, the torque of the motor 1 of this embodiment is increased.

  In the motor 1 of the present embodiment configured as described above, the magnets 8a and 8b are inclined with respect to the radial direction so that the point P is arranged on the outer side, thereby facilitating magnetization while achieving high torque. By using such magnets 8a and 8b, the rotor 3, and thus the motor 1 as a whole can be easily manufactured.

Next, characteristic effects of the present embodiment will be described.
(1) In the present embodiment, the magnets 8a and 8b having different magnetic pole arrangements alternately in the circumferential direction generate a radial magnetic flux passing through one point P on the magnetic pole center line CL set on the outer circumferential side of each magnetic pole. The distance R from the axis L of the rotating shaft 6 to a point P on the magnetic pole center line CL and the distance r from the axis L of the rotating shaft 6 to the surfaces (outer peripheral surfaces) of the magnets 8a and 8b. The ratio value (R / r) is set to 1.1 or more. From the relationship diagram showing the relationship between the value of the ratio of the distances R and r (radial orientation center position) and the torque shown in FIG. 4, the axis L of the rotary shaft 6 is within a range where the R / r value is 1.1 or more. In the case where the orientation is along the radial direction while the point P on the magnetic pole center line CL and the surfaces of the magnets 8a and 8b do not approach each other, that is, the orientation inclination of the magnets 8a and 8b does not increase (in FIG. Torque ratio is larger than “1”). Accordingly, the magnets 8a and 8b can be easily manufactured while the torque output of the motor 1 is improved by inclining the orientation of the magnets 8a and 8b with respect to the radial direction.

  Further, as shown in FIG. 4, when the value of R / r is 1.1 or more and 1.6 or less, when the value is “1”, that is, the orientation of the magnets 8a and 8b is maximum. A torque output larger than that when it becomes the most difficult can be obtained. When the value of R / r is 1.1 or more and 1.2 or less, it can contribute to higher torque even within the range of 1.1 to 1.6, and among them, “1.125”. In the present embodiment, which is set to, a substantially maximum torque improvement effect can be obtained.

In addition, you may change embodiment of this invention as follows.
In the above embodiment, the ratio value (R / r) of the distances R and r is set to “1.125”, but may be changed within a range of 1.1 or more in addition to the value. As the value of R / r is increased, the magnets 8a and 8b are easily magnetized.

In the above embodiment, a total of ten magnets 8a and 8b divided for each magnetic pole are used, but one annular magnet having ten magnetic poles may be used.
In the above embodiment, the number of poles of the stator 2 is 12 (slots) and the number of poles of the rotor 3 is 10. However, the number of poles may be changed as appropriate.

In the above embodiment, the brushless motor 1 is embodied. However, for example, the motor may be embodied in another motor such as a brush motor.
Next, a technical idea that can be grasped from the above embodiment and another example will be added below.

(A) The ratio value (R / r) of the distances R and r is set to 1.1 or more and 2.0 or less.
According to this configuration, it is possible to efficiently improve the torque output of the rotating electrical machine while facilitating manufacture (see FIG. 4).

The schematic diagram which shows the brushless motor in this embodiment. The elements on larger scale of a rotor. The schematic diagram which shows the manufacture aspect of a magnet. FIG. 5 is a relationship diagram showing a relationship between radial alignment center position and torque. The surface magnetic flux density distribution figure of a rotor.

Explanation of symbols

  L: Axis line, CL: Magnetic pole center line, P: One point on the magnetic pole center line CL, 1 ... Brushless motor as a rotating electric machine, 2 ... Stator, 3 ... Rotor, 5 ... Winding, 6 ... Rotating shaft, 8a, 8b …magnet.

Claims (4)

A rotor of a rotating electrical machine in which magnets having different magnetic pole arrangements alternately in the circumferential direction are provided on a rotating shaft so as to be integrally rotatable,
The magnet is magnetized so that a radial magnetic flux passing through one point on the magnetic pole center line set on the outer peripheral side of each magnetic pole is generated,
A ratio value (R / r) between a distance R from the axis of the rotating shaft to a point on the magnetic pole center line and a distance r from the axis of the rotating shaft to the surface of the magnet is set to 1.1 or more. A rotor of a rotating electrical machine characterized by being made. The rotor of the rotating electrical machine according to claim 1,
A rotor of a rotating electrical machine, wherein a ratio value (R / r) of the distances R and r is set to 1.1 or more and 1.6 or less. In the rotor of the rotating electrical machine according to claim 2,
A rotor of a rotating electrical machine, wherein a ratio value (R / r) of the distances R and r is set to 1.1 or more and 1.2 or less. The rotor according to any one of claims 1 to 3,
A rotating electrical machine comprising: a stator provided around the rotor and wound with a winding that generates a magnetic field for rotating the rotor.

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