JP2007306746A - Polyphase motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To use the flux of a ringlike magnet magnetized with multipoles effectively while reducing reluctance on a magnetic circuit and iron loss, and to enhance motor efficiency while reducing vibration by constituting a polyphase motor on one plane. <P>SOLUTION: Assuming the number of magnetic pole plate groups is q, total number of pole teeth is 2qn (n is an integer of 1 or above), and the total number of magnetic poles of a magnet is p, the following relationship is satisfied in the case of a three-phase motor; p=2qn+2 or p=2qn+4, and the following relationship is satisfied in case of a two-phase motor; p=2qn+2. The magnetic pole plates are arranged uniformly, and the magnetic flux of the magnet is taken out to the maximum as the interlinking magnetic flux of motor winding thus generating motor torque uniformly. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric motor, and more particularly to a structure of a flat electric motor having a stator having a plurality of magnetic pole cores wound with windings arranged on the same plane and having claw-shaped claw pole pole teeth.

  FIG. 4 is a cross-sectional view of an electric motor having a two-phase outer rotor structure using a multi-pole magnetized magnet implemented in Japanese Patent No. 3246724.

In FIG. 4, four cylindrical magnetic pole cores 9 are equally spaced on the same circumference that is concentric with the rotating shaft 6, and are arranged so that the axes thereof are in the same axial direction as the rotating shaft 6. Each of the magnetic pole cores 9 is wound with a motor winding 12 via a bobbin 11.
Further, fan-shaped magnetic pole plates 13a are fixed to both ends of each magnetic pole core 9 in the axial direction, and the four magnetic pole plates 13a fixed to one end face of each magnetic pole core 9 are arranged on the same plane, The arc-shaped outer peripheral surface is arranged on the same circumference, and a plurality of pole teeth 14 a called claw poles extending in the axial direction are formed on the arc-shaped outer peripheral surface. Similarly, another magnetic pole plate group having a plurality of pole teeth on the outer periphery and having four magnetic pole plates is arranged so that each pole tooth is nested. The motor is also characterized in that each phase is arranged on the same plane and the motor can be configured flat.

FIG. 6 is a cross-sectional view of a motor having a three-phase inner rotor structure using a multi-pole magnetized magnet which is not a claw pole structure but is implemented according to Japanese Patent No. 3071064. Each of the tips has two or more magnetic teeth of the same number and is substantially opposite to the rotor magnet magnetic pole. Reference numeral 3 denotes a winding, which is provided with a three-phase winding. A first-phase winding is wound around the stator magnetic poles 1-1 and 1-4, and the magnetic poles 1-1 and 1-4 have the same polarity. It is magnetized to become. Similarly, a second phase winding is wound around the magnetic poles 1-2 and 1-5, and a third phase winding is wound around the magnetic poles 1-3 and 1-6. The rotor magnet 2 is a rotor having N and S alternating pitch magnetic properties, and the sum of the N and S poles is P, and P = 12n ± 4 (n is an integer of 1 or more). Has been. At this time, the total number of pole teeth 4 added to the tip of each stator pole is not defined, but the total number of pole teeth needs to be smaller than the total number of magnet magnetization P = 12n ± 4 due to the arrangement of the three-phase pole teeth. There is sex. From the relationship between the pole teeth and magnet poles shown in FIG. 1 of Japanese Patent No. 3071064, the total number of pole teeth is 18 and the total number of magnet poles is 32.
This motor is characterized by extremely low vibration and noise because it uses a multi-pole magnetized magnet with an appropriate air gap.
Japanese Patent No. 3246724 Japanese Patent No. 3071064

  In order to effectively use the magnetic flux of the magnet, the ratio between the total number of pole teeth and the total number of magnetized magnetic poles is preferably close to 1. That is, when the magnetic flux amount of the magnet is taken out as the interlinkage magnetic flux of the motor winding, if the ratio is far from 1, many portions of the magnetic pole of the magnet are not used. In the electric motors disclosed in Japanese Patent Nos. 3246724 and 3071064, there is a problem that the relationship between the number of pole teeth and the total number of magnetic poles of the magnet is not appropriate, and the magnetic flux of the magnet cannot be used efficiently.

The electric motor of the present invention improves the characteristics of the electric motor by using the following means to solve the above-mentioned problems, and sets an appropriate relationship between the number of pole teeth and the total number of magnetic poles of the magnet. It is necessary to increase the number of magnet-attached magnetic poles more than the number of pole teeth because of the arrangement of pole teeth. In addition, the following relationship is required for the total number of magnetic poles of a magnet in order to arrange magnetic pole plate groups having pole teeth and magnetic pole cores at a uniform interval. That is, the number of pole plate groups is q, the total number of pole teeth is 2qn (n is an integer of 1 or more), the total number of magnetic poles of the magnet is p, and in the case of a three-phase motor, p = 2qn + 2 or p = 2qn + 4,2 In the case of a phase motor, p = 2qn + 2.
An object of the present invention is to effectively utilize the magnetic flux of a magnet and to optimally design its structure to reduce loss and improve the characteristics and efficiency of an electric motor.

Each of the magnetic pole groups has pole teeth and has the following excellent characteristics in the multiphase motor in which the multiphase motor windings are arranged on one plane.
1. The ratio between the total number of pole teeth and the total number of magnetized magnetic poles is closest to 1, and the amount of magnetic flux of the magnet can be extracted effectively.
2.2-phase and 3-phase magnetic pole plates can be evenly arranged, and the torque of the motor can be generated uniformly.
3. By making the number of pole teeth of the magnetic pole plate group A and the magnetic pole plate group B the same, there is no magnetic flux imbalance and the vibration of the motor can be suppressed.

  As an electric motor for a three-phase inner rotor, an annular rotating magnet in which N and S are alternately magnetized in the circumferential direction, which is arranged opposite to the inner peripheral surface of the stator via a gap, and the stator rotate. A plurality of magnetic pole cores arranged at equal intervals on the same circumference of the same core as the rotation axis of the magnet and arranged in the same axial direction as the rotation axis, and fixedly wound around each of the magnetic pole cores And a plurality of magnetic pole plate groups A and B having a plurality of pole teeth extending in the axial direction on arcuate inner circumferential surfaces fixed to both axial ends of the magnetic pole cores. The magnetic pole plate groups A fixed to one end face and the magnetic pole plate groups B fixed to the other end face are respectively arranged on the same plane, and their arcuate inner peripheral faces are arranged on the same circumference, The pole teeth of the magnetic pole plate groups A and B are spaced apart from each other and are nested, and the relationship between the number of pole teeth and the number of poles of the annular rotating magnet is The number of magnetic pole plate groups is q, the total number of pole teeth is 2qn (n is an integer of 1 or more), the total number of magnetic poles of the annular rotating magnet is p, p = 2qn + 2, and the number of pole teeth on each pole plate is The arrangement pitch coincides with the pole pair pitch of the annular rotating magnet.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the shape of a stator composed of a magnetic pole plate group A and a magnetic pole plate group B. FIG. 1A is a cross-sectional view of the magnetic pole plate group A, and FIG. 1B is a plan view of the magnetic pole plate group A. FIG. The magnetic pole plate group A is composed of six magnetic pole plates 21-1 to 21-6. Six magnetic pole cores 22 are arranged, and two pole teeth 23 are held in each.
1C is a cross-sectional view of the magnetic pole plate group B, and FIG. 1D is a plan view of the magnetic pole plate group B. The magnetic pole plate group B is also composed of six magnetic pole plates 25-1 to 25-6. Six pole core holes 26 are arranged, and two pole teeth 27 are held in each of them.

FIG. 2 shows the relationship of the arrangement of the pole teeth of the motor winding, the magnetic pole core, and the magnetic pole plate groups A and B. In the figure, reference numerals 31-1 to 31-6 denote electric motor windings inserted into the respective magnetic pole cores, and 32 denotes an annular magnet magnetized on the outer periphery. In the figure, each magnetic pole plate is assigned to the U-phase, V-phase, and W-phase, and has six windings in a three-phase configuration. The total number of pole teeth is 24, with 4 pole teeth per pole core, and two pole teeth are arranged on the pole plate A side and the pole plate B side, respectively. The total number of magnetic poles of the magnet is 28 and is magnetized at an equal pitch.
The relationship between the number of magnetized magnetic poles and the number of pole teeth of the above magnets can be summarized as follows. When the electrical angle deviation amount of each phase is 60 degrees, it can be expressed as P = 2qn + 2, and when the electrical angle deviation amount of each phase is 120 degrees, it can be expressed as P = 2qn + 4.

Further, the relationship when the electrical angle deviation amount of each phase is 60 degrees can be expressed as shown in Table 1. The total number of pole teeth can be expressed as 2nq, where P is the total number of magnetic poles attached to the magnet, n is the number of pole teeth on one pole plate, and q is the number of pole cores. Table 1 (a) shows the relationship between the total number of pole teeth 2qn and the total number of magnetic poles P of the magnet when the number of pole cores q is 3 and the number of pole teeth n of one pole plate is changed. is there. Similarly, Table 1 (b) shows the case where the number of magnetic pole cores q is 6, and similarly Table 1 (c) shows the case where the number of magnetic pole cores q is nine.

The relationship when the electrical angle deviation of each phase is 120 degrees can be expressed as shown in Table 2. Table 2 (a) shows the relationship between the total number of pole teeth 2qn and the total number of magnetic poles P of the magnet when the number of pole cores q is 3 and the number of pole teeth n of one pole plate is changed. Table 2 (b) shows the case where the number of magnetic pole cores q is six.

Table 3 shows the case of a two-phase motor with an electrical angle deviation of 90 degrees for each phase. Table 3 (a) shows the case where the number of pole cores q is two, and the number n of pole teeth on the magnetic pole plate on one side is changed. The relationship between the total number of pole teeth 2qn and the total number of magnetic poles P of the magnet is shown. Similarly, Table 3 (b) shows the case where the number of pole cores q is 4, and similarly Table 3 (c) shows the case where the number of pole cores q is 6.

  FIG. 3A is a development view showing the relationship between the magnetic poles and pole teeth of a ring-shaped magnet when the total number of magnetic poles is 28 and the total number of pole teeth is 24 in a three-phase motor. The lower row is connected continuously. It consists of six magnetic pole plate groups, each magnetic pole plate group has four pole teeth, and the four pole teeth are alternately arranged by the pole teeth 23 and 27 of the magnetic pole plate groups A and B, so The magnetic pole plates are arranged at an equal pitch P1. The interval P2 between the phases is arranged at 120 electrical degrees. P3 is the phase angle between the U phase and the V phase and is shifted by 120 degrees in electrical angle. P4 is the phase angle between the U phase and the V phase and is shifted by 240 degrees in electrical angle. The phase of the three phases is shifted every 120 degrees. Are configured properly. This is a combination corresponding to n = 2 in Table 2 (b).

By arranging the pitch P2 at equal intervals between the pole plates of the pole teeth, the balance of torque generated in the rotation direction is improved, and unnecessary torque ripple and vibration are less likely to occur.
In addition, by making the number of pole teeth (pole teeth 23 and 27) of the magnetic pole plate A and the magnetic pole plate B the same, the upper and lower axial components of the torque generated by the electric motor coincide with each other, and vibration in the axial direction is unlikely to occur.

If the total number of magnetic poles of the magnet is P, the number of pole teeth on one pole plate is n, and the number of pole cores is q, the total number of pole teeth is 2nq. Ideally, the number of phase magnetic poles P and the total number of pole teeth 2nq should be the same, but the condition of P> 2nq is required to secure the electrical angle deviation amount of each phase and arrange them on the same plane. Become. When the ratio of the total number of magnetic poles P of the magnet and the total number of pole teeth 2nq is close to 1, the amount of magnetic flux of the magnet can be used effectively.
The ratio is 1.17 when the total number of magnetized magnetic poles is 28 and the total number of pole teeth is 24.

FIG. 3B shows an arrangement when the total number of magnetic poles of the magnet is 26, and the ratio is 1.08, and the magnetic flux utilization rate of the magnet is better than that of the total number of magnetic poles of 28 magnets. become.
The interval P2 between the phases is arranged at 120 electrical degrees. P3 is the phase angle between the U phase and the V phase and is shifted by -60 degrees in electrical angle, and P4 is the phase angle between the U phase and the V phase and is shifted by 60 degrees in electrical angle. In this case, the winding direction of the winding By reversing, the same operation as 120 degrees can be performed, and the three phases are appropriately configured. This is a combination corresponding to n = 2 in Table 1 (b).

FIG. 3 (c) shows a combination corresponding to n = 2 in Table 3 (b). In the case of a two-phase motor with a total number of magnetic poles of 18 and a total number of teeth of 16, It is an expanded view which shows the relationship of a pole tooth, and the upper stage and lower stage of a figure are connected continuously. It consists of four magnetic pole plate groups, each magnetic pole plate group has four pole teeth, and the four pole teeth are alternately arranged by the pole teeth of the magnetic pole plate groups A and B, and have the same phase (same magnetic pole plate) Inside, they are arranged at an equal pitch P1. The interval P2 between the phases is arranged at an electrical angle of 90 degrees. Further, P3 is a phase angle between the A phase and the B phase, and is appropriately configured with a deviation of 90 degrees in electrical angle and a phase difference of two phases every 90 degrees.
When the total number of magnetized magnetic poles is 18 and the total number of pole teeth is 16, the ratio is 1.13.

  FIG. 3 (d) shows the arrangement when the total number of magnetized magnetic poles is 26 and the total number of pole teeth is 24 in a combination corresponding to n = 3 in Table 3 (b). Thus, the magnetic flux utilization rate of the magnet is better than that of the total number of magnetized magnetic poles of 18.

  As described above, according to the electric motor of the present invention, the number of magnetic poles of the magnet, the number of pole teeth, and the number of magnetic pole cores can be optimally selected in an electric motor in which the windings of each phase are arranged on one plane to reduce the thickness. The magnetic flux utilization rate of the magnet is maximum, the efficiency is high, and the configuration of a magnetic circuit with little vibration is possible.

The figure which shows the stator of this invention The figure which shows the structure of the electric motor of this invention The figure which shows the arrangement | sequence of the magnetic pole and pole tooth of the magnet of this invention Diagram showing the configuration of a conventional electric motor Diagram showing the configuration of a conventional electric motor

Explanation of symbols

1: Stator magnetic pole 3: Winding 4: Polar teeth 6: Rotating shaft
9: Cylindrical magnetic pole core 11: Bobbin 12: Winding 13: Magnetic pole plate 14: Pole teeth 21: Pole plate group A
22: magnetic pole core 23: pole teeth of magnetic pole plate group A 25: magnetic pole plate group B
26: magnetic pole hole 27: pole teeth 31 of magnetic pole plate group B: winding 32: annular magnet

Claims (3)

  A stator having a stator winding 31, and an annular rotary magnet 32 in which N and S are alternately magnetized in the circumferential direction disposed opposite to each other through a gap on the inner peripheral surface of the stator, A plurality of magnetic pole cores 22 arranged such that the stator is equally spaced on the same circumference concentric with the rotation axis of the rotating magnet, and the axis is in the same axial direction as the rotation axis; A stator winding having a stator winding wound around each of the magnetic pole cores and a plurality of pole teeth (claw poles) 23 and 27 extending in the axial direction on arcuate inner peripheral surfaces respectively fixed to both axial ends of the magnetic pole cores. The magnetic pole plate groups A and B, and the magnetic pole plate groups A fixed to one end face of each of the magnetic pole cores and the magnetic pole plate groups B fixed to the other end face are arranged on the same plane. The arc-shaped inner circumferential surface is arranged on the same circumference, and the pole teeth of the magnetic pole plate groups A and B are spaced apart from each other. The number of pole teeth and the number of poles of the annular rotating magnet are represented by q, the number of the pole plate groups is q, the total number of pole teeth is 2qn (n is an integer of 1 or more), and the total number of the annular rotating magnets is The three-phase claw pole is characterized in that the number of magnetic poles is p, p = 2qn + 2, or p = 2qn + 4, and the arrangement pitch of the pole teeth on each magnetic pole plate matches the pole pair pitch of the annular rotating magnet. Inner rotor type electric motor having. A stator having a stator winding, and an annular rotary magnet having N and S alternately magnetized in the circumferential direction and arranged opposite to each other through an air gap on the inner peripheral surface of the stator. A plurality of magnetic pole cores, each of which is arranged on the same circumference that is concentric with the rotating shaft of the rotating magnet and spaced so that the shaft is in the same axial direction as the rotating shaft, Stator windings wound respectively, and a plurality of pole teeth (claw poles) extending in the axial direction on arcuate inner peripheral surfaces fixed to both axial ends of each of the magnetic pole cores
The magnetic pole plate groups A and B each having the same shape, and the magnetic pole plate groups A fixed to one end face of the magnetic pole cores and the magnetic pole plate groups B fixed to the other end face are on the same plane. The arc-shaped inner peripheral surface is arranged on the same circumference, the pole teeth of the magnetic pole plate groups A and B are arranged in a nesting manner spaced apart from each other, and the number of pole teeth and the annular rotating magnet The number of pole plates is q, the total number of pole teeth is 2qn (n is an integer of 1 or more), the total number of magnetic poles p of the annular rotating magnet is p = 2qn + 2, and each pole plate An inner rotor type electric motor having a two-phase claw pole, characterized in that the arrangement pitch of the pole teeth is matched with the pole pair pitch of the annular rotating magnet. A stator having a stator winding, and an annular rotating magnet having N and S alternately magnetized in the circumferential direction, which are arranged opposite to each other through a gap on the outer circumferential surface of the stator, A plurality of magnetic pole cores arranged at equal intervals on the same circumference of the same axis as the rotation axis of the rotary magnet so that the axes are in the same axial direction as the rotation axis, and each of the magnetic pole cores. 2. A stator-shaped magnetic pole plate group A and B having a plurality of pole teeth extending in the axial direction on arcuate outer peripheral surfaces fixed to both ends in the axial direction of the magnetic pole cores, respectively, and wound stator windings. And an outer rotor type electric motor having a three-phase or two-phase claw pole described in (2).