JPS6087649A - 6-pole, 2-coil, small-sized dc brushless motor - Google Patents

Abstract

PURPOSE:To enable to manufacture a DC brushless motor inexpensively in a mass production by generating poles of opposite polarity in salient poles on which drive coil are wound, and salient poles on which drive coils are not wound, thereby reducing the drive coils. CONSTITUTION:Drive coils 56-1, 56-2 are wound only on T-shaped salient poles 54-1, 54-2 of a brushless motor 36'. Drive coils 56-1 are energized to generate S- poles at the poles 54-1 and to generate N-poles at the poles 54-3 on which the drive coil is not wound and symmetrical with the pole 54-1 so as to generate the same polarity as the pole 51 of a field magnet 48 to repel them from each other. Then the drive coil 56-2 of the pole 54-2 is energized to generate the S-pole and to generate the N-pole at the pole 54-4. The pole 54 is repelled from the magnet 48 by the above operation to rotate in the direction A.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a 6-pole device with good efficiency, smooth rotation, very low rotational noise, and the ability to reduce the number of armature coils to half, which is inexpensive and has good efficiency. , relates to a small two-coil DC brushless motor.

Conventionally, the two-pole field magnet shown in Fig. 1,
3-phase small DC brushless motor with 3 salient poles and 3 coils 1
is 1. It is well known that it can be produced at low cost and with good efficiency. This type is the most commonly used commutator motor. This is because it is cheaper and more efficient than a small 2-phase 4-coil DC motor.

The structure of this 2-pole, 3-coil, 3-phase small DC brushless motor 1 will be explained below. This □ brushless motor 1 has a stator core 2 shown in FIG. 2 on the fixed side. A two-pole field magnet 6 whose outer periphery is shown in FIG. 3 rotates, and does not require brushes or commutators. This DC brushless motor 1 has a stator core 2 having three salient poles shown in FIG. 2 fixed on a fixed base 4. As shown in FIG. In the stator core 2, each salient pole 5 has a single-shape shape, and the three salient poles 5 are radially connected at equal intervals, and a rotating shaft insertion hole 6 is formed in the center of the joint. A drive coil 7 is connected to the T-shaped salient pole 5 of the fixed tongue core 2 in an i-line. This single-shaped salient pole 5 is connected to the coil 7
The portion 8 is wound thinly, and the outer circumferential portion 9 is widened in the circumferential direction. The opening angle of the outer periphery 9 of the T-shaped portion is 180 degrees or less, such as 90 degrees (depending on the object). Therefore, counter torque enters and the efficiency is poor, but a considerable rotational torque can still be obtained. It is something that can be done. Bearings 10 and 11 are fixed to the inner circumference of the rotating shaft insertion hole 6 by a bearing support member 12.

The rotating shaft 16 is rotatably supported by bearings 10 and 11, and a rotor yoke 14 is attached to the rotating shaft 16.
is fixed, and the stator core 2 of the force/impump type rotor yoke is
On the inner circumferential surface facing the
A two-pole annular field magnet 3 whose poles are magnetized with an opening angle width of 180 degrees is fixedly installed, and rotates around the outer periphery of the stator core 2. Position detection elements 15 such as three Hall elements and Hall ICs are arranged at appropriate locations on the outer periphery of the stator iron rcs 2, and detect the N and S magnetic poles of the field magnet 6 to detect the drive coils 7 groups. The rotor is rotated in a predetermined direction by sequentially applying current in an appropriate direction to the rotor. 16 is a printed circuit board.

In the small DC brushless motor 1 having such a configuration, during rotation operation, when the rotor is rotated from a stable position through an unstable state to a stable position by energizing the coil 7, a large coking angle occurs, resulting in smooth rotation. It has the disadvantage of not being able to operate. As a result, when rotating at high speeds, a loud rotation noise is produced that is unpleasant to the ears. Therefore, it is not suitable for brushless fuzzy motors used in office machines, automobiles, etc., which must rotate quietly, and all companies have been struggling with the problem of eliminating this harsh and loud rotating sound. .

However, regarding this issue, due to the corrosive nature of the rotating motor,
This is a situation that is difficult to resolve.

For this purpose, as shown in Fig. 4, there is a design in which the number of salient poles 17 is doubled to 6, and a luer is wound around each of them, but there is not much difference in terms of efficiency (and vice versa). had the disadvantage of being expensive.

Particularly in the case of small motors, it is impossible to raise the price to an extreme degree because there are very strict conditions for improving efficiency and keeping the price the same, or reducing the price while maintaining the same efficiency. For this reason, motors are rotary motors that are simple in principle with few components, but even slight improvements can result in large differences and benefits in terms of efficiency, etc., so there have been many The current situation is that many inventions have been made and a large number of applications have been filed. In addition, we increased the number of poles of the field magnet to twice that of 4 poles, and
JP-A-54, which reduced coking and enabled smooth rotation.
Although this improves the performance of the 4-pole, 3-salient-pole, 3-coil, 3-phase brushless motor shown in No. 57608, it also has the disadvantage of being extremely expensive.

An example of a structure with grooves on the salient pole is the Japanese Patent Application Laid-Open No. 53
There is also a 2-pole, 3-salient pole, and 3-coil type shown in No. 147216, but they have the same disadvantage of being expensive, and they also introduce counter torque, so they do not increase efficiency. In addition, it is a 3-phase brushless motor with 3 salient poles and 3 coils, which is said to be better than a 2-phase motor because it can obtain a large rotational torque and is better in terms of efficiency. However, since it has 4 salient poles, it can rotate smoothly (if possible, a 2-phase small DC brushless motor with 4 salient poles and 4 coils will reduce the rotation noise of a fan motor, etc.). It has attracted interest as it is suitable for fields of concern.

A typical 4 salient pole, 4 coil, 2-phase small DC brushless motor will be explained using FIG. 5. This 2-phase small DC brushless motor 18 is an outer rotor motor. , field magnet 19 is N, S
It has four driving magnetic poles with alternating magnetic poles,
It is fixed to the rotor yoke 20 and rotates around the outer periphery of the stator core 21. The stator core 21 is 4
T-shaped salient poles 22 are formed at regular intervals, and a drive coil 26 is wound around each salient pole 22. A Hall IC 24 is used as the position detection element.

The drive coil 23 has two coils for the first Aikawa Ichi and second furnaces wound in a bifurcated manner so that each coil is excited by opposite magnetic poles. In this brushless motor 18 of FIG. 5,
The feature is that the gap length of the salient pole portion of the stator core gradually increases in the clockwise direction, and the structure is simple, but the disadvantage is that the efficiency is poor because the gap length is inevitably long. Another conventional example is U.S. Patent 3
．． There is one shown in FIG. 6 disclosed in No. 299,635. The motor shown in Fig. 6 is an inner rotor motor, and utilizes auxiliary salient poles.

The stator core 25 has four main salient poles 26 radially formed at equal intervals, and a driving filter 28 is wound around the salient poles 26, and small auxiliary protrusions 27 are formed between the main salient poles 26.
is formed. Field Magne Nod.

29 is alternately magnetized with N pole, S pole, and 0 pole (non-magnetic pole). Such a two-phase small DC brushless motor 60 shown in FIG.
is certainly useful, but since there is a non-magnetized portion, there is a large dork crease, which prevents smooth rotation, and it also has the disadvantage of being extremely inefficient. - A two-phase small DC brushless motor shown in FIG. 7 is attracting attention as a motor that eliminates the drawbacks of the motors shown in FIGS. 5 and 6. In the brushless motor shown in FIG. 7, the field magnet 61 shown in FIG. 7(a) is
It becomes an outer rotor motor that rotates around the outer periphery of the stator core 62 shown in FIG.

As is clear from FIG. 7(a), the field magnet 31 is a four-pole ms magnet with N and S magnetic poles alternately spaced at equal intervals.
8 in which magnetic pole 51a and N and S magnetic poles are alternately magnetized.
The ratio a:b of the driving magnetic pole 31a and the auxiliary magnetic pole 31b is 2:j, and the auxiliary magnetic pole 31 of the 4-pole driving magnetic pole 31a is
The two poles of b overlap. Similar to the brushless motor 30 shown in FIG. 6, the stator core 32 has four main salient poles 63 and four salient poles between them (although there is a difference between the outer rotor type and the inner rotor type). Auxiliary salient pole 34
The drive coil 35 is wound only around the main salient pole 63,
So that the polarity is the same as the pole located 80 degrees opposite,
It has two sets of windings with two sets connected in series. A Hall element is provided at a location (not shown) to detect the position of the rotor, and the field current is switched by a transistor depending on the relative position to the stator core 62 to obtain torque in a fixed direction.

In the brushless motor having such a configuration, dead points are eliminated by the above-described composite field magnet 67 and auxiliary salient poles 34. Furthermore, the generated torque may be generated by combining the four driving magnetic poles 31a and the eight auxiliary magnetic poles 61b).

Brushless motors with such a configuration are known to be practically useful because they only require one position detection element, and because they operate in two-phase, half-wave IJ17 mode, the number of circuit components is small and each circuit can be made small. It is being

However, even though the brushless motor is known to be useful, it has auxiliary salient poles, so
Since it is necessary to use a composite field magnet L1, the structure is complicated and difficult to manufacture, and it is also expensive. Furthermore, since there is an auxiliary salient pole, it is difficult to wind the drive coil around the main salient pole, making it difficult to mass-produce it.

Furthermore, a driving magnetic pole 31 for generating the main torque
Since a has four poles, even though the N and S poles are magnetized with an opening angle of 90 degrees, the opening angle of the main salient pole 33 is formed to be less than 90 degrees. Because of this, counter-torque was introduced and the efficiency was poor (although it goes without saying that it is still more efficient than the conventional one). Therefore, based on the above technical background, the present applicant developed a two-phase compact DC brushless motor that can be mass-produced with high efficiency and low cost, which can rotate smoothly at the beginning, does not generate harsh and loud rotation noise, and can also obtain large rotational torque. The motor was provided. This 6-pole, 4-coil, 2-phase compact brushless motor will be described below with reference to FIG. 8 and subsequent drawings.

Referring to FIG. 8, 36 is a two-phase small DC brushless motor having a six-pole field magnet, four salient poles, and four coils, and is an outer rotor motor. 37 is a flat fixed side cup body, 68 is a stator core, and 39 is a stator core support body, which is fixed to the cup body 37. Reference numeral 40 denotes a disk-shaped printed circuit board, which is fixed to the cup body 37 and the support body 39, and is provided between the inner surface of the cup body 37 and the printed circuit board 40 for the electrical components 41 for the energization control circuit arranged on the printed circuit board 40. A storage space 42 is formed.

46 is a fixed shaft, and 46 is a rotor, which rotates around the outer periphery of the fixed shaft 46 by bearings 44 and 45. 47
is a flat cup-shaped rotor yoke fixed to the connecting member 49, and the rotor yoke 47 has six cylindrical poles on the inner circumferential surface 50 with N and S magnetic poles alternately magnetized in the circumferential direction. A field magnet 48 having a driving magnetic pole 51 is fixedly provided and faces the outer periphery of the stator core 38 . On the lower end surface of the field magnet 48, six position detecting magnetic poles 52 are formed at positions in the same phase as the driving magnetic poles 51 by double magnetization means or the like. The N and S poles of the position detecting magnetic pole 52 are formed at the same magnetic pole positions as the driving magnetic pole 51. 53 is a Hall element, Hall IC.

The field magnet 48 is a position detection element such as a magnetic resistance element.
It is disposed by soldering at a position on the printed circuit board 40 facing the position detection magnetic pole 52 .

Referring to FIG. 9, the driving magnetic pole 51 and the position detection magnetic pole 5
2 are formed so that the N or S magnetic poles are within the same magnetic pole, and the six-pole field magnet 48 having such magnetic poles 51 and 52 rotates around the outer periphery of the stator core 68. There is.

Since the field magnet 48 has six drive magnetic poles 51 (same as the position detection magnetic poles 52), the N and S poles are each magnetized with an opening angle width of 60 degrees. The stator core 38 is made of, for example, a silicon steel plate.
The four salient poles are formed by radially connecting four T-shaped salient poles 54 at equal intervals μ, and a drive coil 56 is wound around the constriction 55 of each of the four T-shaped salient poles 54. There is a line. The circumferential umbrella portion 57 of the T-shaped salient pole 54 facing the field magnet 48 is formed to have an opening angle approximately equal to the magnetic pole width of the field magnet 48, that is, an opening angle of 60 degrees. In this way, there is no counter-torque as in the conventional case, a large rotational torque is obtained, and the motor becomes an efficient two-phase small DC brushless motor. As is clear from FIG. 9, the T-shaped salient poles 54-1 and 54-3, 54-2 and 54-4 are formed at 180 degree symmetrical positions, and two symmetrical salient poles, for example 54- 1. When 54-3 faces the north pole or the south pole, the remaining two salient poles 54-2 and 54-4 face the dead point (the boundary between the north pole and the south pole). There is. If the field magnet 48 is 41rIjA, four salient poles 54-1. . . , 54-4 may face a dead point and become unable to start automatically, but this motor 36 does not have such a risk.

FIG. 10 shows the field magnet 48 and the drive coil 56-1.
..., 56-4, each drive coil 56-1
．． . . , 56-4 are respective salient poles 54-1 . ...
, 54-4. As is clear from this developed view, the opening angle of the conductor portions 56a and 56b of the drive filters 56-1°..., 56-4 that contribute to rotational torque is the same width as 1fix of the field magnet 48, that is, Since the motor has a high rotational speed, no counter-torque is generated, a large rotational torque is obtained, and the motor becomes an efficient two-phase rotational motor. This happens because the T-shaped salient poles 54-1..., 56-4 are not actually formed to have an opening angle of 60 degrees. ..., 54-4
This is because the peripheral umbrella portion 57 is formed to have an opening angle width of 60 degrees. Drive coil 56-1. . . , 56-4 are each connected to the energization control circuit 58 at one end, and the other ends are commonly connected to the positive power terminal 59.

60 is ground.

The position detection elements 53-1 and 53-2 are respectively arranged at positions facing the conductor portions 56a that contribute to the rotational torque of the drive coils 5 (S-1, 56-2).

In the state shown in FIG. 10, the position detection element 53-2 detects the S pole of the position detection magnetic pole 52, so the transistor q is made conductive and the drive coil 56- is connected to the transistor Q.
Rotation torque in a predetermined direction is obtained by conducting current through the drive coil 56-4 in a suitable direction as described above. In addition, the position sensing element 53-1 is the N pole or the S pole.
When a pole is detected, transistor Q1 or Q becomes conductive, and
Rotational torque in a predetermined direction can be obtained by applying current in a predetermined direction to the drive coil 56-1, 56-3.

In this way, a 2-phase small DC brushless motor with 6 pole field magnets, 4 salient poles, and 4 coils has the following features: (1) The N and S driving magnetic poles of the field magnet are made into 6 poles and spaced at equal intervals. The circumferential umbrella portion facing the formed four T-shaped salient pole field magnets is connected to the driving G? Since the opening angle width is approximately equal to the magnetic pole width of 1 jN, no counter torque is generated, large torque is obtained, and a highly efficient two-phase compact brushless smoke is obtained.

(2) Also, in this case, since the field magnet has six poles instead of four, it can be self-starting, and the rotor rotates smoothly because the current is rectified more smoothly than a four-pole one. (3) Since the stator core has 4 salient poles, it has a better balance than the conventional 3 salient pole, and the rotor rotates smoothly, and even when rotating at high speeds, it does not produce loud rotational noise. It will significantly stop occurring. (4) Unlike conventional two-phase small DC brushless motors, there is no need to use auxiliary salient poles or composite magnets, so the configuration is simple and one production can be done at low cost. (5) Also, since there is no auxiliary salient pole, or the width between the salient poles is narrower compared to the one with three salient poles, 5! T.I.J.
) This has a tremendous practical effect in that a coil can be wound into a salient pole extremely easily.

It is clear that it would be more convenient if this useful small DC brushless motor could be mass-produced at a lower cost.

The present invention was made based on such circumstances, and moreover, it was made for the purpose of obtaining a small, inexpensive DC brushless motor. In addition, the above figures 5, 6 and 7
The DC brushless motor shown in the figure cannot be started if the number of drive coils is reduced by half as in the present invention.

The present invention will be described in detail with reference to FIG. 11 and subsequent drawings.

Referring to FIG. 11, it is an explanatory diagram of the structure of a small DC brushless mocrochronograph with 6fL4 salient poles and 2 coils according to the first embodiment of the present invention, and its structure is almost the same as that shown in No. 9;21. However, in this brushless motor 36', the drive coil 56-1.56 is attached only to the salient pole 541.54-2.
FIG. 12, in which the wire is wound, is a developed view of the field magnet and the drive coil, and corresponds to FIG. 10. 1st
In the state shown in FIG.
Salient pole 54-6 with no drive coil wound symmetrical to -1
The figure shows a state in which a N pole is generated, the polarity is the same as that of the magnetic pole 51 of the field magnet 48, and the rotor is rotated by a half magnetic pole in the direction of arrow A. Furthermore, in the state shown in FIG. 11, if the drive coil 56-2 of the salient pole 54-2 is energized to generate an S polarity, the salient pole 54-4 can generate an N polarity. , field magnet 4
8 and rotate in the direction of arrow A in the same manner as above.

12 is the same as that explained in FIG. 10, so a description thereof will be omitted.

FIG. 13 shows a second embodiment of the present invention, and is an explanatory diagram of the structure of a small DC brushless motor 36' in which salient poles are devised so that only one position detection element 53 is required.

The structure and operation are almost the same as those shown in FIG. 11, but the salient pole 54-1. ..., 54-4 has been devised. Each thrust 41M54-1. ..., 54-4 is
The salient pole surface 54a is connected to the field magnet 48.
The air gap 61 between the position sensing elements 5
We have devised a way to be able to drive even one 3. In this way, the salient poles are positioned in the narrow portion of the air gap 61 and stabilized. That is, when the motor 36' is stopped, it always stops at a position where it can self-start, avoiding a dead point, so that even one position sensing element 56 can be self-starting.

FIG. 14 is a torque waveform of the brushless motor 3f shown in FIG. 13, and shows the relationship between the position of the rotor (field magnet 4B) and the torque (curve 62 in FIG. 14). The torque curve 62 is the salient pole 54-1. ..., the torque due to coking by 54-4, at the stable point 66, the curve 6
2 cuts 0 in the upper right direction. These stable points 66 and 63
There are zero torque points 64 between the two, but these are unstable points and tend to rotate in either direction with a small amount of external force. A brushless motor 66" has a 6 field magnet 48 and four salient poles 5.4-1...

54-4, the torque curve 62 of FIG. 14 is obtained. Next, the relationship between torque and rotation angle % when current flows through the drive coils 56-1 and 56-2 is shown by curve 65.
It will be like 65. Zero point 6 of these curves 65.65'
6 is a salient pole 54-1. ....

There is a slight CW force direction from the zero point 66 of the torque due to coking of 54-4. Position detection element 56 and energization control circuit 58
(See Figure 15), the torque due to the drive coil 56-1, 56-2 and the field magnet 48 becomes the upper half of the curve 65°65' (the part shown by the dotted line). Therefore, the torque curve obtained by combining with the torque curve 64 becomes as shown by the reference numeral 67. In other words, there is no dead point and the brushless motor '5
6' becomes stable and rotates.

FIG. 15 shows the field magnet 48 and the drive coil 56-1.
56-2. The other end of the drive coil 56-1 and one end of the drive coil 56-2 are connected, and the drive coil 56
-1 is connected to a connection point 68 between the collectors of transistors Ql and Q2 in the energization control circuit 58, and the other end of the drive coil 56-2 is connected to a connection point 69 between the collectors of transistors Q3 and Q4. There is. transistor q and q3
The emitter of transistor Q2 is connected to the positive power supply terminal 59.
The emitters of Q4 and Q4 are connected to ground 60. The position detection element 53 is disposed by soldering on the printed circuit board 40 at a position opposite to the radial position detection magnetic pole 52 of the conductor portion 56a that contributes to the generated torque of the drive coil 56-2 (see FIG. 8). ).

Therefore, in FIG. 15, since the position detection element 53 detects the S pole of the position detection magnetic pole 52, the signal from the output terminal 70 of the position detection element 53 turns on transistors q and q and drives them. The coils 56-1 and 56-2 are energized, a rotational torque in a predetermined direction is obtained from the drive coil 56-2 (in the figure, no rotational torque is generated from the drive coil 56-1), and the field is A rotor having a magnet 48 rotates in a predetermined direction. Position detection 21
When one element 56 detects the N pole, a signal via the output terminal 71 energizes the drive coil 56-1. It will be done.

As is clear from the above, the 6-pole, 2-coil compact DC brushless motor of the present invention has the following advantages: (1) It has a good rotational balance, so the rotation noise is extremely low, (2) It is easy to wind the drive coil, and (3) ) The configuration is very simple, and the drive coil is half that of the conventional one, so the small DC brushless motor with good performance can be mass-produced at low cost. Since there are no
The effect of obtaining a product having the characteristics of 3) is enormous.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a conventional three-phase small DC brushless motor with two pole field magnets, three salient poles, and three coils.
Fig. 2 is a perspective view of the stator core shown in Fig. 1, Fig. 3 is a perspective view of the two-pole field magnet shown in Fig. 1, and Fig. 4 is a conventional two-pole field magnet, six salient poles, A plan view showing the state of the field magnet and stator core in a 3-phase small DC brushless motor with 6 coils. A cross-sectional view of a small DC brushless motor, FIGS. 6 and 7 are explanatory diagrams of other conventional small two-phase DC brushless motors having four coils, and FIG. 8 is a cross-sectional view of a small DC brushless motor according to the applicant's earlier application. An example of a 6-pole field magnet, 4 salient poles, 4
A vertical cross-sectional view of a two-phase small DC brushless motor with coils, FIG. 9 is an explanatory diagram showing the relationship between the field magnet and the stator core in FIG. 8, and FIG. 10 is a diagram showing the relationship between the field magnet and the drive coil group. , FIG. 11 is a structural explanatory diagram of a small DC brushless motor according to the first embodiment of the present invention, FIG. 12 is a developed diagram of the field magnet and drive coil group in the motor of FIG. 11, and FIG. A structural explanatory diagram of a small DC brushless motor according to a second embodiment of the present invention, FIG. 14 is a torque curve of the motor of FIG. 13, and FIG. 15 is a developed view of the field magnet and drive coil group in the motor of FIG. 13. 01... 3-phase small DC brushless motor, 2...
3 salient pole stator core, 3...2 pole field magnet 7
), 4... Fixed pedestal, 5... T-shaped salient pole piece, 6
... Rotating shaft insertion hole, 7... Drive coil, 8...
Coil winding is as follows: 9...outer circumference, 10, 11...
・Bearing, 12... Bearing support member, 13... Rotating shaft,
14... Cup-shaped rotor yoke, 15... Position detection element, 16... Printed circuit board, 17... Salient pole piece, 1
8... 4-pole field magnet, 4 salient poles, 2-phase small DC brushless motor with 4 coils, 19... Field magnet, 20... Rotor yoke, 21... Stator core, 22... Salient pole, 26... Drive coil, 24
...Hall IC125...Stator core, 26...
-Main salient pole, 27...Auxiliary salient pole, 28...Drive coil, 29...Field magnet, 60...2-phase small DC brushless motor, 61...Field magnet soto, 31a ... Drive magnetic pole, 31b... Auxiliary magnetic pole,
62... Stator core, 63... Main salient pole, 64...
...Auxiliary salient pole, 65...Drive coil, 66...6
A small 2-phase DC brushless motor with a field magnet, 4 salient poles, and 4 coils; A small DC brushless motor with a 36', 56...6 pole field magnet, 4 salient poles, and 2 coils; 67...Flat fixed side cup body, 38...Stator core, 69...Stator core support, 40...Printed circuit board, 41...Electrical component for energization control circuit, 42... Gap, 43... Fixed shaft, 44. 45... Bearing, 46... Rotor, 47...
...Rotor yoke, 48...6-pole field magnet,
49... Connection member, 50... Inner peripheral surface, 51... Drive magnetic pole, 52... Position detection magnetic pole, 56... Position detection element, 54... T-shaped salient pole, 55 ... Constriction part, 56 ... Drive coil, 57 ... Circumferential umbrella part, 58
...Electrification control circuit, 59...Plus power terminal, 6
0...Ground, 61...Air gap, 62.
...Torque curve due to coking, 66...Stable point, 6
4... Zero point, 65.65'... Coil generated torque curve, 66... Zero point, 67... Composite torque curve. Patent Applicant No. 1M Figure 2 Figure 3: 4th Edict Figure 5 also 6 Figure 7 7 Figure 7 Procedural Amendment 1981/P Month 2P Director General of the Patent Office Kazuo Wakasugi Tono Motor 3 Person making the amendment Drawing 5 Contents of amendment (1) Figure 13 of the drawing will be revised as shown in the attached sheet.

Claims (2)

[Claims] (1) Four T-shaped salient poles are radially connected at equal intervals, and a drive coil is wound around two adjacent protrusions of the salient poles,
A six-pole field magnet having N and S driving magnetic poles alternately is provided on the surface facing the circumferential surface of the salient pole, and the opening angle of the circumferential surface of the T-shaped salient pole is determined by the magnetic pole width of the field magnet. , the iron core side having the salient poles is used as a stator, the field magnet is used as a rotor, and the drive coil is wound by energizing the drive coil to form a coil with the salient poles. A salient pole with a polarity opposite to that around which the drive coil is wound and 180
A small 6-pole, 2-coil direct current brushless motor, characterized in that the rotor is rotated by forming degree-symmetrical drive coils on unwound salient poles. (2) In the above-mentioned 6-pole, 2-coil small DC motor, the air gap between the salient pole surface and the field magnet gradually increases in a predetermined direction, causing coking. 6 poles according to claim (1), characterized in that the six poles can be driven by one position detection element;
A small DC brushless motor with 2 coils.