JPH10150760A - Pulse driven brushless motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive brushless motor having simple structure which can be rotary driven by applying a single pulse train without requiring any pole position sensor, e.g. a Hall element. SOLUTION: The pulse driven brushless motor comprises a rotor arranged, at a constant interval, with three rotor poles 2a-2c of same polarity, first and second stator poles 4, 5 each comprising an electromagnet, and a third stator pole 6 comprising a permanent magnet. The second stator pole 5 is located while being spaced apart by (90+α) deg. (α is a bias angle of 15 deg., for example) from the first stator pole 4 in the circumferential direction and the third stator pole 6 is located while being spaced apart by (180+α) deg. from the first stator pole 4 in the circumferential direction. The stator poles 4-6 have air gaps G arranged asymmetrically to the rotor poles 2a-2c and the pulse motor is driven by applying a monopolar ON/OFF drive pulses to the first and second stator poles 4, 5 at a predetermined interval.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulse-driven brushless motor suitable for use as a vibration motor in a vibrator such as a portable telephone or a pager.

[0002]

2. Description of the Related Art Some portable telephones and pagers are provided with a vibrating caller which is called by vibration (vibration) in order to avoid inconvenience to the surroundings. This vibrating caller is configured to generate a vibration by attaching a weight having an eccentric center of gravity to a rotating shaft of a motor and rotating the weight. Conventionally, as a vibration motor used in such a vibration caller, DC
Micromotors with small brushes were common.

[0003]

The brush motor has a problem of mechanical noise and electric noise generated during rotation. In particular, measures against electric noise are expensive. In order to solve this noise generation, a brushless motor or a stepping motor may be used. However,
In the case of brushless motors, it is necessary to accurately detect the magnetic pole position of the rotor in order to create a rotating magnetic field, and a magnetic pole position sensor such as a Hall element is indispensable, which complicates the structure and increases cost. There was a problem.
Further, in the case of the stepping motor, there is a problem that a complicated drive circuit for generating a rotating magnetic field is required, and the cost is high.

The present invention has been made to solve the above problem, and does not require a magnetic pole position sensor such as a Hall element, and has a simple structure that can be rotationally driven only by applying a single pulse train. And a low-cost pulse-driven brushless motor.

[0005]

In order to achieve the above object, a pulse-driven brushless motor according to claim 1 is provided.
A rotor in which an odd number of rotor poles having the same polarity are magnetized at equal intervals on the circumference, a first stator pole made of an electromagnet that is excited to a polarity different from the rotor pole, and magnetized to the same pole as the rotor pole. A second stator pole made of an electromagnet, and a third stator made of a permanent magnet magnetized to a polarity different from that of the rotor pole.
And the second stator pole is disposed at a position in a circumferential direction (90 + α) ° (α is a predetermined deviation angle) with respect to the first stator pole, and the third stator pole is disposed. The poles are arranged at positions in the circumferential direction (180 + α) ° with respect to the first stator poles, and the air gap of each stator pole is asymmetric with respect to each rotor pole.

According to a second aspect of the present invention, there is provided a pulse-driven brushless motor having a rotor in which an odd number of rotor poles having the same polarity are magnetized at equal intervals on a circumference, and an electromagnet which is excited to have the same polarity as the rotor poles. And a second stator comprising a permanent magnet magnetized to a polarity different from that of the rotor pole.
And the second stator pole is disposed in the circumferential direction (180 + α) ° (α) with respect to the first stator pole.
Are arranged at a predetermined deviation angle).

In a pulse-driven brushless motor according to a third aspect of the present invention, a rotor in which two rotor poles having different polarities and one starting auxiliary pole are magnetized at a predetermined interval on the circumference has a different polarity. First and second stator poles comprising electromagnets which are alternately excited, and wherein the second stator pole is circumferentially (180 + α) ° with respect to the first stator pole.
(Α is a predetermined deviation angle).

Further, the pulse-driven brushless motor according to claim 4 has the same polarity as a rotor in which two rotor poles having the same polarity and one starting auxiliary pole are magnetized at a predetermined interval on the circumference. First and second stator poles made of electromagnets to be excited, wherein the second stator pole is arranged in a circumferential direction (180 + α) ° (α is a predetermined deviation angle) with respect to the first stator pole. It is characterized by being arranged at a position.

[0009]

In the case of the pulse-driven brushless motor according to the first aspect, unipolar driving pulses for turning on / off are applied to the first and second stator poles composed of electromagnets at predetermined intervals, and the first and second driving pulses are applied. A magnetic pole having a different polarity is generated in the stator pole. Thereby, a magnetic force is generated between the rotor and the first to third stator poles, and the rotor rotates.

In the case of the pulse-driven brushless motor according to the second aspect, the first stator pole made of an electromagnet is turned on / off.
A unipolar drive pulse to be turned off is applied at predetermined intervals to generate a magnetic pole different from the magnetic pole of the third stator pole made of an electromagnet. As a result, a magnetic force is generated between the rotor and the first and second stator poles, and the rotor rotates.

According to a third aspect of the present invention, in the pulse-driven brushless motor according to the first aspect of the present invention, first and second stator poles composed of electromagnets are applied at predetermined intervals with bipolar driving pulses alternately switched between positive and negative. A different magnetic pole is generated alternately between the pole and the second stator pole. As a result, a magnetic force is generated between the rotor and the first and second stator poles, and the rotor rotates.

In the pulse-driven brushless motor according to the present invention, a unipolar drive pulse for turning on / off is applied to the first and second stator poles made of electromagnets at predetermined intervals, and the first stator pole and the first stator pole are connected to each other. A magnetic pole having the same polarity as the first and second rotor poles is generated at the second stator pole. As a result, a magnetic force is generated between the rotor and the first and second stator poles, and the rotor rotates.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a pulse-driven brushless motor according to the present invention (hereinafter abbreviated as “motor”).
1 shows a first embodiment. The first embodiment is an example of a so-called inner rotor type motor in which a rotor is positioned inside a stator and rotates. A rotor 2 rotates inside an outer case 1 forming a yoke (yoke). The rotor 2 is rotatably supported by a shaft 3. Outside the rotor 2,
First and second stator poles 4 and 5 each comprising an electromagnet;
A third stator pole 6 made of a permanent magnet is provided. The rotor 2 has three rotor poles 2a, 2 made of permanent magnets that are magnetized so that the outer surface side is an S pole.
b, 2c are formed at 120 ° intervals on the circumference.

The second stator pole 5 is located at a position separated from the first stator pole 4 by 105 ° in a counterclockwise direction;
That is, 90 ° counterclockwise from the first stator pole 4
It is disposed at a position deviated counterclockwise from the separated position by a deviation angle α = 15 °. On the other hand, the third stator pole 6 is offset 165 ° in the clockwise direction from the first stator pole 4, that is, the bias angle α = 15 ° in the counterclockwise direction from the 180 ° opposite position of the first stator pole 4. It is disposed at a position deviated only by this. By providing such a deviation angle, a rotational force in the direction of arrow A is always generated in the rotor 2.

The first stator pole 4 has a drive winding 7
However, drive windings 8 are wound around the second stator pole 5, respectively. When a drive pulse described later is applied to these windings, N The poles are configured such that S poles are respectively generated on the surface of the second stator pole 5. Also, a third permanent magnet
The stator pole 6 is magnetized so that its surface becomes an N pole.

Further, the first stator pole 4 and the third stator pole 6 have an asymmetric magnetic pole surface shape such that the air gap G expands in the direction of rotation of the rotor 2 as indicated by the arrow A. In addition, the second stator pole 5 has an asymmetric magnetic pole surface shape such that its air gap G expands in the direction opposite to the rotation direction of the rotor 2 as indicated by the arrow A. With such a pole face shape, the rotation direction of the rotor 2 is designed to always be in the direction of the arrow A.

The motor having the above configuration is finished in an external shape as shown in FIG. 2, and a semi-cylindrical weight 9 is attached to an end of the rotating shaft 3 extending from the outer case 1 to the outside. The eccentric rotation of the rotor 2 is caused by the semi-cylindrical weight 9 so that the motor vibrates.

Next, the operation of the first embodiment will be described with reference to FIG.
The operation will be described with reference to FIG. In the state where the drive pulse is not applied, as shown in FIG. 3A, no magnetic poles are generated in the first and second stator poles 4 and 5, which are electromagnets. The first and second stator poles 4, 5 can be regarded as simple iron blocks. Therefore, when the drive pulse is not applied, the three rotor poles 2a, 2b, 2
3C, the rotor pole closest to the third stator pole 6 made of a permanent magnet, for example, as shown in FIG. 3A, the first rotor pole 2a attracts the stator pole 6,
The rotor 2 is stopped with the first rotor pole 2a facing the stator pole 6 as shown.

In the stop state shown in FIG. 3A, a drive pulse P as shown in FIG. 4 is applied to the drive winding 7 of the first stator pole 4 and the drive winding 8 of the second stator pole 5. When applied at the same time, as shown in FIG. 3B, an N pole is generated in the first stator pole 4 and a second stator pole 5 is formed.
Generates an S pole. Thereby, the third rotor pole 2
c and the second stator pole 5 have the same pole, and a repulsive force acts on the second rotor pole 2c in the direction of arrow B. Further, the second rotor pole 2b and the first stator pole 4 have different polarities, and an attractive force acts on the second rotor pole 2b in the direction shown by the arrow C. At this time, the third rotor pole 2c is larger than the overlapping area between the first stator pole 1 and the second rotor pole 2b.
And the second stator pole 5 has a larger overlapping area, the repulsion force of the arrow B is much larger than the suction force of the arrow C, and the rotor 2 starts rotating in the direction of the arrow A according to the difference.

An attraction force due to the different polarity acts between the first rotor pole 2a and the third stator pole 6 made of a permanent magnet, and the rotor 2 rotates as shown in FIG. As the operation proceeds, a suction force acting in the opposite direction to the rotational direction as shown by the arrow d acts between the first rotor pole 2a and the third stator pole 6, and the direction of the arrow d Drive pulse P consisting of a large current that overcomes the suction force of
Is applied, the rotor 2 keeps rotating in the direction of arrow A as it is.

When the rotor 2 rotates to the state shown in FIG. 3C, the third rotor pole 2c and the second stator pole 5c are rotated.
The repulsion force between and gradually decreases, but conversely,
The attraction force E between the third rotor pole 2c and the first stator pole 4 increases, and the rotor 2 remains in FIG.
It rotates to the state of (D). Then, the drive pulse P is turned off at the time of rotation to the position shown in FIG.

When the drive pulse P is turned off in the state of FIG. 3D and the excitation of the drive windings 7 and 8 is stopped, the motor is brought into a state as shown in FIG. 3E and the first and second electromagnets are provided. The magnetic poles of the stator poles 4 and 5 are eliminated, and only the attraction between the permanent magnets acts between the second rotor pole 2b and the third stator pole 6, and the rotor 2 is directly moved by the attraction by the attraction. Continue rotating in the direction of a
It rotates to the state of (F).

FIG. 3F shows the state of the second rotor pole 2b.
Is a state facing the magnetic pole surface of the third stator pole 6, which is a permanent magnet, and is electromagnetically illustrated in FIG.
This is the same as the state of FIG. Therefore, in the state shown in FIG. 2F, if the drive pulse P is applied again, the rotor 2
3 (B), (C), (D),
(E) and rotate. Therefore, if the drive pulse P is continuously applied, the rotor 2 continues to rotate and becomes a motor.

FIG. 6 shows the rotational torque characteristics of the motor according to the first embodiment. As is clear from this figure,
The rotational torque of the rotor 2 is always in the forward direction (the direction of the arrow A in FIG. 3), and it can be seen that the rotor 2 rotates without stopping.

In the case of the first embodiment, the rotor 2 rotates by 120 ° every time one driving pulse P is applied, so that the rotor 2 makes one rotation with three pulses. Therefore, if the repetition frequency of the drive pulse P is variably controlled, the rotation speed of the motor can be freely changed. Further, the drive pulse P to be applied is O at a predetermined duty ratio.
A single pulse train for N-OFF may be used, and unlike a conventional stepping motor, a plurality of parallel supply pulse trains with slightly different phases for generating a rotating magnetic field are not required, so that the driving circuit configuration is extremely simple. Become. Further, since it is not necessary to detect the positions of the magnetic poles 2a to 2c of the rotor 2, a magnetic pole position sensor such as a Hall element is not required unlike a conventional DC brushless motor, and the structure of the motor itself can be extremely simplified. .

In the first embodiment, as shown in a combination (1) in FIG.
The poles, the second stator pole 5 are S poles, the third stator pole 6 is N poles, and the three rotor poles 2a, 2b, 2c are all set to S poles. As shown by a combination (2) in FIG. 5, the first stator pole 4 is an S pole, the second stator pole 5 is an N pole, the third stator pole 6 is an S pole, and two rotor poles 2a. The same can be realized even if the magnetic pole relationships are set such that all of the magnetic poles 2c to 2c are N poles.

FIG. 7 shows a second embodiment of the present invention.
The second embodiment is an example of a so-called outer rotor type motor in which a rotor is positioned outside the stator and rotates, and the rotor and the stator of the first embodiment are inverted inside and outside. is there. That is, as shown in FIG. 7, the cylindrical rotor 1 is located inside the outer case 11.
2 is rotatably supported by a rotating shaft 13,
The stator poles 14, 15, and 16 formed in a trifurcated shape are fixedly arranged inside the rotor 12. The first stator pole 14 and the second stator pole 15 have the driving winding 1
7 and 18 are wound and used as electromagnets, the third stator pole 16 is used as a permanent magnet, and its magnetic pole surface is magnetized with an N pole. The rotor 12 is magnetized with S poles made of permanent magnets at intervals of 120 ° on the circumference.

The motor according to the second embodiment differs from the motor according to the first embodiment only in that the positions of the rotor and the stator are reversed inside and outside.
Since the operation is exactly the same as that of the first embodiment, the description of the operation will be omitted. Further, as shown in FIG. 8, the polarity relationship between the stator pole and the rotor pole may be reversed.

FIG. 9 shows a third embodiment of the present invention.
In the third embodiment, the stator has a two-pole structure, and the rotor 22 is provided inside the outer case 21 with the rotating shaft 2.
3 and a first stator pole 2 made of an electromagnet outside the rotor 22.
4 and a second stator pole 25 made of a permanent magnet. The rotor 22 has three rotor poles 22a, 22b, and 22c formed of permanent magnets magnetized such that the outer surface thereof is an S pole at intervals of 120 ° on the circumference.

A driving winding 26 is wound around the first stator pole 24. When a driving pulse P as shown in FIG. 10 is applied to this winding, an S pole is formed on the surface thereof. Is configured to occur. On the other hand, the second stator pole 25 made of a permanent magnet is magnetized so that an N pole is generated on the surface thereof, and is shifted from the position opposite to the first stator pole 24 by 180 ° by a deviation angle α = 15 °. It is arranged at a position shifted counterclockwise. By providing such a deviation angle, a rotational force in the direction of arrow A is always generated on the rotor 22.

The motor according to the third embodiment rotates as follows. That is, when the driving pulse is not applied, when the rotor 22 is stopped, the rotor 22 is connected to one of the three rotor poles, for example, as shown in FIG. And stopped at the illustrated position. In this state, FIG.
When the driving pulse P is applied, an S pole is generated on the surface of the first stator pole 24. Therefore, the S pole of the first stator pole 24 repels the S pole of the rotor pole 22b, and the rotor 22 starts rotating in the direction of arrow A. At this time, the second stator pole 25 and the rotor pole 22a attract each other,
A driving pulse P having a current value large enough to overcome this force
May be applied.

When the rotor 2 rotates, the second rotor pole 22b
Is turned off from the magnetic pole surface of the first stator pole 24, the drive pulse P is turned off. The rotor 2 continues to rotate as it is due to its inertia and the attraction between the rotor pole 22b and the second stator pole 25 made of a permanent magnet. And the third
Of the second rotor pole 22c shown in FIG.
At the time when the motor rotates to the position b, the drive pulse P is applied again. In this manner, by applying the drive pulse P at a constant cycle, the rotor 22 continues to rotate and functions as a motor.

As apparent from the above description, in order for the motor according to the third embodiment to rotate, the first
The reluctance (non-energized) torque of the stator pole 24
1, when the torque when the first stator pole 24 is energized is T2, and when the constant torque of the second stator pole 25 is T3,
It is necessary that the condition of 1 <T3 <T2 be satisfied. Also, in the case of the third embodiment, as shown in FIG. 11, the same can be realized even if the magnetic pole relationship between the stator pole and the rotor pole is reversed. Further, instead of the illustrated inner rotor type, an outer rotor type may be configured.

FIG. 12 shows a fourth embodiment of the present invention. In the fourth embodiment, a rotor 32 is rotatably supported by a rotating shaft 33 inside an outer case 31, and first and second two stators made of electromagnets are provided outside the rotor 32. The poles 34 and 35 are arranged. The rotor 32 has a first rotor pole 32a composed of N poles, a second rotor pole 32b composed of S poles, and a small starting auxiliary pole 32c composed of N poles.
The first rotor pole 32a and the second rotor pole 32b are about 13
The auxiliary poles 32c are arranged at an interval of 5 °, and the first and second rotor poles 32a, 32
It is located at the opposite position on the bisector of b.

Further, a drive winding 36 is wound on the first stator pole 34, and a drive winding 37 is wound on the second stator pole 35, respectively.
3, the driving pulses P ₊ and P ₋ inverted to positive and negative are applied. When the positive driving pulse P ₊ is applied, the first stator pole 34 has an N pole, and the second stator pole 35 has an S pole. Occurs, and when a negative drive pulse P _- is applied,
The first stator pole 34 is configured to generate an S pole, and the second stator pole 35 is configured to generate an N pole. The second stator pole 35 is disposed at a position shifted clockwise by a deviation angle α = 15 ° from a position 180 ° opposite to the first stator pole 34, and by providing such a deviation angle, the rotor is rotated. 32 is configured to always generate a rotational force in the direction of arrow A.

The motor according to the fourth embodiment rotates as follows. That is, when the drive pulse is not applied, the rotor 32 is stopped in the state shown in FIG. In this state, FIG.
When the positive drive pulse P ₊ is applied, an N pole is generated on the surface of the first stator pole 34 and an S pole is generated on the surface of the second stator pole 35. As a result, the first stator pole 34 and the first rotor pole 32a have the same polarity as the N poles, and
The second stator pole 35 and the second rotor pole 32b become the same pole of the S pole, a repulsive force acts between the magnetic poles, and the rotor 32 starts rotating in the direction of arrow A.

When the rotor 32 rotates in the direction of arrow A, the starting auxiliary pole 32c approaches the second stator pole 35, so that an attractive force is applied between the starting auxiliary pole 32c and the second stator pole 35. Acting, the rotor 32 rotates further.
Then, the rotor 2 further rotates, and the first rotor pole 32
When “a” approaches the second stator pole 35, an attractive force acts between the first rotor pole 32 a and the second stator pole 35, and the second rotor pole 32 b also acts on the first stator pole 34. Since it approaches, the attraction force acts between the first rotor pole 32a and the first stator pole 34, and the rotor 32 further rotates.

When the magnetic pole face of the first rotor pole 32a overlaps the magnetic pole face of the second stator pole 35, the positive drive pulse P ₊ is turned off as shown in FIG. Then, when the rotor 2 is first rotor poles 32a rotating at its inertia has reached the position of the second rotor pole 32b in FIG. 12, as shown in FIG. 13, this time negative driving pulse P _- Is applied.

As a result, an S pole is generated on the surface of the first stator pole 34, and an N pole is generated on the surface of the second stator pole 35. Therefore, the first stator pole 34 and the second
Rotor pole 32b has the same polarity as the S pole, and the second stator pole 35 and the first rotor pole 32a have the same polarity as the N pole. A repulsive force acts between the magnetic poles. Rotate further in the direction of arrow a. In this way, by applying the positive and negative drive pulses every half rotation of the rotor 32, the rotor 32 rotates continuously.

It should be noted that also in the case of the fourth embodiment, FIG.
As shown in FIG. 4, the same can be realized even if the polarity relationship between the stator poles and the rotor poles is reversed. Further, instead of the illustrated inner rotor type, an outer rotor type may be configured.

FIG. 15 shows a fifth embodiment of the present invention. The fifth embodiment is an example of a so-called outer rotor type motor in which the positions of the rotor and the stator of the fourth embodiment are reversed inside and outside. That is, as shown in FIG. 15, a cylindrical rotor 42 is rotatably supported by a rotating shaft 43 inside the outer case 41, and a stator pole 44, 4
5 is even fixed. Drive windings 46 and 47 are wound around the first stator pole 44 and the second stator pole 45, and each is an electromagnet. Also, the rotor 42
A first rotor pole 42a composed of N poles, a second rotor pole 42b composed of S poles, and a small third rotor pole 42b composed of N poles are magnetized.

The motor according to the fifth embodiment differs from the motor according to the fourth embodiment only in that the positions of the rotor and the stator are reversed inside and outside, and the operation itself is exactly the same. The operation is omitted. Also,
As shown in FIG. 16, the N and S relationships between the stator pole and the rotor pole may be reversed.

FIG. 17 shows a sixth embodiment of the present invention. The sixth embodiment has the same structure as the motor according to the fourth embodiment shown in FIG. 12 in terms of structure. Only. That is, all of the first and second rotor poles 32a and the starting auxiliary pole 32c are
The first and second stator poles 3
The configuration is such that both 4 and 35 are simultaneously magnetized to the same N-pole, and are driven to rotate by a unipolar drive pulse P shown in FIG. Accordingly, since the structure of the motor itself is the same, the same portions as those of the motor according to the fourth embodiment are denoted by the same reference numerals, and the detailed description of the structure is omitted.

The motor according to the sixth embodiment rotates as follows. In other words, when the driving pulse is not applied, the operation is stopped in the state shown in FIG. When the drive pulse P shown in FIG. 18 is applied in this state, the first and second stator poles 34, 3
An N-pole is generated on each surface of No. 5. As a result, the first stator pole 34 and the first rotor pole 32a
The poles are the same, and the second stator pole 35 and the second rotor pole 32b are the same poles of the N poles. A repulsive force acts between the magnetic poles, and the rotor 32 rotates in the direction of arrow a. Start.

Then, the first and second rotor poles 32
The drive pulse P is turned off at the time when the a and 32b depart from the magnetic pole surfaces of the first and second stator poles 34 and 35, and the first
Then, the excitation of the second stator poles 34, 35 is stopped.
The rotor 2 continues to rotate due to its inertia, and when the first rotor pole 32a reaches the position of the second rotor pole 32b in FIG. 17, the drive pulse P is applied again as shown in FIG. Thereby, the first and second rotor poles 3
2a and 32b receive the repulsive force of the same magnetic pole from the stator poles 34 and 35 again, and rotate in the direction of arrow a in the same manner as described above. Thus, by applying the drive pulse P every half rotation of the rotor 32, the rotor 32 rotates continuously.

In the case of the sixth embodiment, FIG.
As shown in FIG. 9, the same can be realized even if the magnetic pole relationship between the stator pole and the rotor pole is reversed. Further, instead of the illustrated inner rotor type, an outer rotor type may be configured.

Although the embodiments of the present invention have been described above, these examples show an example in which the numbers of the stator poles and the rotor poles are the smallest basic numbers. May be provided with a plurality of the above basic combinations. When a plurality of sets of stator poles and rotor poles are provided, the rotational torque of the motor can be increased.

[0048]

As described above, according to the first aspect of the present invention, a rotor in which an odd number of rotor poles having the same polarity are magnetized at equal intervals on the circumference and a rotor having a different polarity from the rotor poles is excited. A first stator pole made of an electromagnet to be formed, a second stator pole made of an electromagnet excited to the same pole as the rotor pole, and a third stator made of a permanent magnet magnetized to a polarity different from that of the rotor pole. A stator pole, and the second stator pole is arranged in a circumferential direction (9) with respect to the first stator pole.
0 + α) °, and the third stator pole is arranged in a circumferential direction (18) with respect to the first stator pole.
0 + α) °, and the air gap of each of the stator poles is made asymmetrical with respect to each of the rotor poles, so that a magnetic pole position sensor such as a Hall element is not required, and a unipolar ON / OFF switch is provided. It is possible to provide an inexpensive pulse-driven brushless motor that has a simple structure and can be driven to rotate simply by applying a driving pulse.

According to the second aspect of the present invention,
A rotor in which an odd number of rotor poles of the same polarity are magnetized at equal intervals on the circumference, a first stator pole made of an electromagnet excited to the same polarity as the rotor poles, and a rotor having a different polarity from the rotor poles. And a second stator pole made of a magnetized permanent magnet, and the second stator pole is arranged at a position (180 + α) ° in the circumferential direction with respect to the first stator pole, so that a Hall element or the like can be used. No need for a magnetic pole position sensor,
In addition, it is possible to provide an inexpensive pulse-driven brushless motor that can be rotationally driven only by applying a unipolar driving pulse to be turned on / off.

According to the third aspect of the present invention,
A rotor in which two rotor poles having different polarities and one starting auxiliary pole are magnetized at predetermined intervals on the circumference, and first and second stator poles composed of electromagnets which are alternately excited with different polarities; And the second stator pole is arranged at a position of (180 + α) ° in the circumferential direction with respect to the first stator pole, so that a magnetic pole position sensor such as a Hall element is not required, and moreover, It is possible to provide an inexpensive pulse-driven brushless motor having a simple structure, which can be rotationally driven only by providing alternately switched bipolar drive pulses.

Further, according to the present invention, two rotor poles having the same polarity and one starting auxiliary pole are magnetized at the same polarity as the rotor which is magnetized at a predetermined interval on the circumference. And first and second stator poles made of electromagnets, and the second stator pole is disposed at a position in the circumferential direction (180 + α) ° with respect to the first stator pole, so that a Hall element or the like can be used. No need for a magnetic pole position sensor,
In addition, it is possible to provide an inexpensive pulse-driven brushless motor that can be rotationally driven only by applying a unipolar driving pulse to be turned on / off.

[Brief description of the drawings]

FIG. 1 is a principle structural diagram of a first embodiment.

FIG. 2 is an external perspective view showing a state where an eccentric weight is attached to the motor.

FIG. 3 is an explanatory diagram of a rotation operation according to the first embodiment.

FIG. 4 is a waveform diagram of a driving pulse used in the first embodiment.

FIG. 5 is a combination diagram of a stator pole and a rotor pole in the first embodiment.

FIG. 6 is a diagram showing a rotational torque characteristic of the motor according to the first embodiment.

FIG. 7 is a principle structural diagram of a second embodiment.

FIG. 8 is a combination diagram of a stator pole and a rotor pole in a second embodiment.

FIG. 9 is a principle structural diagram of a third embodiment.

FIG. 10 is a waveform diagram of a drive pulse used in the third embodiment.

FIG. 11 is a combination diagram of a stator pole and a rotor pole in a third embodiment.

FIG. 12 is a principle structural diagram of a fourth embodiment.

FIG. 13 is a waveform diagram of a driving pulse used in the fourth embodiment.

FIG. 14 is a combination diagram of a stator pole and a rotor pole in a fourth embodiment.

FIG. 15 is a principle structural diagram of a fifth embodiment.

FIG. 16 is a combination diagram of a stator pole and a rotor pole in a fifth embodiment.

FIG. 17 is a principle structural diagram of a sixth embodiment.

FIG. 18 is a waveform diagram of a drive pulse used in the sixth embodiment.

FIG. 19 is a combination diagram of a stator pole and a rotor pole according to a sixth embodiment.

[Explanation of symbols]

 Reference Signs List 1 outer case 2 rotor 2a first rotor pole 2b second rotor pole 2c third rotor pole 3 rotating shaft 4 first stator pole (electromagnet) 5 second stator pole (electromagnet) 6 third stator pole (Permanent magnet) 7 Drive winding 8 Drive winding 9 Weight 11 Outer case 12 Rotor 12a First rotor pole 12b Second rotor pole 12c Third rotor pole 13 Rotation axis 14 First stator pole (electromagnet) 15 Second stator pole (electromagnet) 16 Third stator pole (permanent magnet) 17 Drive winding 19 Drive winding 21 Outer case 22 Rotor 22a First rotor pole 22b Second rotor pole 22c Third rotor pole 23 Rotation axis 24 First stator pole (electromagnet) 25 Second stator pole (permanent magnet) 26 Drive winding 31 Outer case 32 Rotor 32a First rotor pole 32b Second Rotor pole 32c starting auxiliary pole 33 rotating shaft 34 first stator pole (electromagnet) 35 second stator pole (electromagnet) 36 drive winding 37 drive winding 41 outer case 42 rotor 42a first rotor pole 42b first Second rotor pole 42c Third rotor pole 43 Rotation axis 44 First stator pole (electromagnet) 45 Second stator pole (electromagnet) 46 Drive winding 47 Drive winding G Air gap

Claims (4)

[Claims] 1. A rotor in which an odd number of rotor poles having the same polarity are magnetized at equal circumferential intervals, a first stator pole made of an electromagnet excited to a polarity different from that of the rotor poles, and A second stator pole made of an electromagnet excited to the same polarity; and a third stator pole made of a permanent magnet magnetized to a polarity different from that of the rotor pole. And the third stator pole is arranged in a circumferential direction (180 + α) with respect to the first stator pole. °, and the air gap of each of the stator poles is asymmetric with respect to each of the rotor poles. 2. A rotor in which an odd number of rotor poles having the same polarity are magnetized at equal intervals on a circumference, a first stator pole made of an electromagnet excited with the same polarity as the rotor poles, and the rotor poles. The second consists of a permanent magnet magnetized to a different polarity
Pulse driving, wherein the second stator pole is disposed at a position in a circumferential direction (180 + α) ° (α is a predetermined deviation angle) with respect to the first stator pole. Type brushless motor. 3. A first and a second rotor comprising two rotor poles having different polarities and one starting auxiliary pole magnetized at predetermined intervals on a circumference, and electromagnets which are alternately excited with different polarities. Wherein the second stator pole is disposed at a position in a circumferential direction (180 + α) ° (α is a predetermined deviation angle) with respect to the first stator pole. Driven brushless motor. 4. A first and a second rotor comprising a rotor in which two rotor poles having the same polarity and one starting auxiliary pole are magnetized at a predetermined interval on a circumference, and electromagnets excited in the same polarity. And a stator pole, wherein the second stator pole is disposed at a position in a circumferential direction (180 + α) ° (α is a predetermined deviation angle) with respect to the first stator pole. Brushless motor.