JPH08107662A - Brushless dc motor - Google Patents

Abstract

PURPOSE: To lift a rotor without any bearing and to drive it by lifting a rotary disk by the repulsion force between same electrodes and at the same time rotating the rotary disk with the attraction force between a stator magnetic pole and a magnet magnetic pole. CONSTITUTION: 2n (n>=2) sets of magnetic poles of a magnet 14 with N and S poles are laid out on the plane of a rotary disk 13 while the same poles are aligned at an equal space and the magnetic pole of 3n stators for performing three-phase conduction so that it is the same electrode as the magnetic electrode of the magnet 14 on the rotary disk 13 are laid out while it opposes the magnetic pole of the magnet 14 on the rotary disk 13. Then, two phase out of the three-phase stator magnetic pole are allowed to conduct and the magnetic pole of the magnet 14 on the rotary disk 13 is lifted in repulsion, at the same time the rotary disk 13 is rotated and moved by the attraction force between the remaining one-phase non-conduction stator and the magnetic pole of the magnet 14 on the rotary disk 13. Further, by switching a conduction pattern, a stable still magnetic lifting and rotation can be obtained, thus lifting the rotor without any bearing and driving it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brushless DC motor, and more particularly to a rotor having magnet poles of two or more pairs of N and S poles arranged axially symmetrically, and a stator winding arranged on the outer periphery of the rotor. Brushless DC with a fixed stator
Regarding motors.

[0002]

2. Description of the Related Art FIG. 16 shows an example of such a conventional brushless DC motor and its driving method.
Shows the cross-sectional structure, and (B) shows a time chart of current switching of the stator winding. The rotor 1 of this brushless DC motor has a total of 4 magnetic poles of 2 pairs of N and S poles.
The poles are arranged at axially symmetrical positions on the outer peripheral surface of the cylindrical rotor 1. The magnetic pole surface of the stator iron core 4 is arranged on the outer periphery of the rotor 1 so as to be separated from and face the magnet magnetic pole surface of the rotor 1, and the stator winding 3 is wound around the iron core 4. The stator iron core 4 has a structure protruding from the stator (stator) 2, and is made of a magnetic material having a high magnetic permeability such as silicon steel. As shown in the figure, the stator 2 includes a stator iron core 4 having 6 poles, and each iron core 4 is wound with U, V, and W phase windings 3. Further, although not shown, a rotation position detecting device such as a hall element for detecting the magnetic pole position of the outer peripheral surface of the rotor 1 in which magnet magnetic poles are arranged is provided, and the on / off of the electric current supplied to each winding 3 according to the rotation state of the rotor is turned on / off. An energization control device for switching between inversion and inversion is provided.

The operation of this brushless DC motor is as follows. As shown in the drawing, in the state where the center of the pole width of the S pole of the rotor 1 is at the position coincident with the W-phase iron core, the winding 3 of the W-phase iron core is not energized and the U- and V-phase iron cores on both sides thereof are not energized. To U
The phase iron core is energized so as to become the N pole, and the V phase iron core is energized so as to become the S pole. Then, the repulsive force acts on the N-pole magnet of the rotor and the U-phase magnetic pole (N-pole) of the stator, and the attractive force acts on the N-pole magnet of the rotor and the V-phase magnetic pole (S-pole) of the stator, so that the rotor 1 A rotational force in the direction indicated by the arrow in the figure is applied. When the rotor 1 rotates 30 °, the center of the magnetic pole width of the S pole of the rotor 1 reaches a position facing the U-phase iron core of the stator 2. At this point, the energization of the U-phase iron core to the winding 3 is stopped, and the winding 3 is energized so that the V-phase iron core becomes the N pole and the W-phase iron core becomes the S pole. Then, a repulsive force is generated between the V-phase stator core (N pole) and the rotor N-pole, and an attractive force is generated between the W-phase stator core (S pole) and the rotor N-pole. Occurs. In this way, the rotor 1 is set at a mechanical angle of 3
A rotating magnetic field is formed by switching the energization of each winding 3 of each phase iron core 4 on the side of the stator 2 every 0 ° rotation, and the rotor 1 rotates in synchronization with this.

However, in such a brushless DC motor, although the forces applied to the rotor 1 seem to be balanced at first glance, the rotor magnetic pole is a magnet between the stator iron core 4 and the rotor magnetic pole which are not energized. Therefore, the suction force always works. When the center of the rotor 1 is deviated, the balance of the force acting on the rotor 1 is lost, and the attraction force acts on the rotor 1 in the more deviated direction, and the bearing supporting the rotor 1 supports this unbalanced load. I had to do it. Incidentally, Japanese Patent Laid-Open No. 3-22845 discloses a prior art related to a brushless DC motor.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and a levitation force is always applied to a rotor in which magnet magnetic poles of a brushless DC motor are arranged in axially symmetrical positions. An object of the present invention is to provide a brushless DC motor that can operate.

[0006]

In the brushless DC motor according to the first aspect of the present invention, 2n sets (n ≧ 2) of magnet magnetic poles of N and S poles are arranged on the plane of the rotating disk at equal intervals. Three-phase stators are arranged side by side, and the magnetic poles of the 3n stators that perform three-phase energization so as to be the same poles as the magnet magnetic poles on the rotating disk are arranged facing the magnet magnetic poles on the rotating disk. By energizing two phases among the magnetic poles, the magnetic poles on the rotating disk are repelled and levitated, and the rotating disk is rotated by the attraction force between the remaining one-phase non-energized stator and the magnetic poles on the rotating disk. Further, the rotation is continuously maintained by switching the three-phase energization pattern in accordance with the position of the magnet magnetic pole.

According to the second aspect of the present invention, all the magnet magnetic poles arranged on one surface of the rotating disk are N poles, and all the magnetic poles arranged on the opposite surface are S poles. The stator magnetic pole surface is inclined from the plane perpendicular to the axis of the rotating disk, and the stator magnetic pole structure is provided by sandwiching the magnet magnetic pole surfaces on both sides of the rotating disk with the stator iron cores so as to have the same poles. .

According to a third aspect of the present invention, there is provided an energization pattern in which the three-phase energization pattern is rotationally driven and the three-phase all-phase direct current is energized to repel and stand up. It is characterized by performing.

In the brushless DC motor according to a fourth aspect of the present invention, 2n sets (n ≧ 2) of permanent magnets having N and S poles are arranged on the rotor circumference so that all surfaces facing the stator magnetic poles have the same pole. 2n rotor magnetic poles are arranged at equal intervals and
The stator magnetic poles facing the rotor magnetic poles are magnetic poles formed by winding 3n number of windings and three phases of windings at equal intervals. It is characterized in that the two-phase stator magnetic poles become the same poles as the rotor magnetic poles and repel each other, the rotor is rotationally moved, and the three-phase energization pattern is switched to continuously rotate the rotor.

According to a fifth aspect of the present invention, the stator magnetic pole is composed of a permanent magnet and a winding, or a permanent magnet, an iron core and a winding. Both phases repel the rotor magnetic poles, and by energizing only two of the three phases in opposite directions, three types of three-phase energization are achieved, so that at least two-phase stator magnetic poles repel the rotor magnetic poles. In addition, the rotor is rotationally driven, and the energization pattern is switched to continuously rotate the rotor.

The invention according to claim 6 is characterized in that the diameter of the circumference connecting the centers of the stator magnetic poles is larger or smaller than the diameter of the circumference connecting the centers of the rotor magnetic poles.

According to the structure of claim 1 of the present invention described above, among the three-phase stator magnetic poles, two phases are energized so that the two magnetic poles have the same polarity as the opposing magnetic poles, so that repulsive levitation is caused on the rotating disk. Power can be applied. By deenergizing the remaining one phase of the three-phase stator magnetic poles, an attractive force acts between the stator magnetic poles, which are magnetic materials, and the magnet magnetic poles to rotate the rotating disk.

According to the second aspect of the present invention, since the magnet magnetic pole and the stator magnetic pole surface are arranged so as to be inclined with respect to the plane perpendicular to the rotating disc axis, the attractive force and the repulsive force are directed in the direction perpendicular to the rotating disc axis. It has a component, namely centripetal force. Therefore, the rotating disk rotates while being sandwiched between the stator magnetic poles and being floated and held at the axial center portion thereof.
That is, the rotor of the motor can be rotatably supported by a shaft without using a bearing. Also, one side of the magnet magnetic pole arranged on the rotating disk is the N pole, and the other side is the S pole.
By using the poles, the configuration can be simplified.

Further, according to the third aspect of the present invention, since it is possible to switch between the energization pattern for rotational driving and the energization pattern for repulsive floating and stationary, it is possible to arbitrarily control the rotation / stop of the motor.

According to the configuration of claim 4 of the present invention, 3
The rotor can be repulsively levitated by energizing so that at least two phases of the stator magnetic poles of the phases have the same poles as the opposing magnet magnetic poles. Further, the rotor can be rotated by applying three types of forces (at least two types of which are repulsive forces) to the three-phase stator and the rotor magnetic poles.

According to the invention of claim 5, the stator magnetic pole is composed of a permanent magnet and a winding, or a permanent magnet, an iron core and a winding, and the stator magnetic pole is the same as the rotor magnetic pole in advance. The rotor can be repulsively levitated even when the power is off. Further, the stator poles of the three-phase can obtain three kinds of magnetic force (of which at least two phases are the same pole as the rotor magnetic pole) only by passing the same current in opposite directions to only two phases of the three-phase windings. Therefore, the rotor can be rotationally moved by an easy energization method.

According to the invention of claim 6, the diameter of the circumference connecting the center of the magnetic poles of the stator is larger or smaller than the diameter of the circumference connecting the center of the magnetic poles of the rotor. Centripetal force is given from the stator magnetic poles, and the gyro effect during rotation is also superimposed, so that stable centripetal force can be obtained.

Further, if the motor of the present invention is a combination of two motors composed of disc rotors as shown in the following embodiments, the rotor can obtain centripetal force in the axial direction and the radial direction. Therefore, the motor only needs to have the auxiliary bearing.

[0019]

Embodiments of the present invention will be described below with reference to the accompanying drawings 1 to 15. In the drawings, the same reference numerals indicate the same or corresponding parts.

FIG. 1 shows a planar structure of a brushless DC motor of the first embodiment of the present invention, and FIG. 2 shows a sectional structure taken along line XX of FIG. This motor is suitable for a scanner motor that rotates a polygon mirror or the like at high speed. Conventionally, since this type of motor is driven at the highest possible speed of rotation, it has been common to use an air bearing, a magnetic bearing, or the like machined with high precision as a bearing for supporting the rotor. Therefore, the cost required to manufacture the bearing is high. The brushless DC motor of this embodiment has both the rotational drive function and the magnetic bearing function of repulsion-free control so that the rotor can be levitated and driven without a bearing.

A rotating disk 13 made of a non-magnetic material is fitted on the outer circumference of the output shaft 10, and a magnet 14 is mounted on the outer circumference thereof.
The magnet magnetic pole has one surface as an N pole and the opposite surface as an S pole, and the magnet magnetic pole surface and the stator magnetic pole surface are inclined from the plane perpendicular to the axis of the rotating disk. The magnetic pole surfaces on both sides of the rotating disk are sandwiched between the magnetic pole surfaces of the stator iron core 11.

The stator iron core 11 has a U-shaped iron core around which the stator winding 12 is wound to form an electromagnet, and three sets of stator iron core magnetic pole surfaces are evenly provided for each rotating disk magnetic pole surface. In this case, each magnetic pole surface is sandwiched with a predetermined gap from the rotor magnetic pole surface so that each rotating disk magnetic pole surface faces the stator core magnetic pole surface. In this embodiment, an example is shown in which one side has eight poles on the rotating disk side and twelve poles on the stator side.

A method of driving the motor of this embodiment is shown in FIGS. 3 to 6. 3 and 5 are plan views showing the arrangement of magnetic poles on the rotor side and the stator side, and FIGS. 4 and 6 are time charts for current switching. 3 and 4 show the energized state when the levitation is stationary, and FIGS. 5 and 6 show the energized state when the rotary drive is performed. 3 and 5, the rotor magnetic pole position is difficult to see when viewed from the top of the motor as in FIG. 1, and therefore the stator is open to the outer periphery.

During stationary levitation, a constant DC current is supplied to each of the U, V and W phases. All the stator magnetic poles facing the N pole of the magnet magnetic pole are N poles, and all the stator magnetic poles facing the S pole of the magnet magnetic pole are S poles.
4 receives the repulsive force and the rotating disk 13 floats still. Since the magnet magnetic pole (N1 pole) with the rotor position angle of 0 ° directly faces the U-phase stator magnetic pole, it becomes unstable due to rotational forces in both left and right directions. On the other hand, the magnet magnetic pole (N2 pole) with the rotor position angle of 45 ° is V phase (30
°) and the W-phase (60 °) stator magnetic poles receive a repulsive force of the same magnitude and enter a stable state. When energized, the positions N1 'and N2' shown by dotted lines in the figure, which are the positions for balancing these forces, are shown.
Stop ascending at.

During rotational driving, the position of the magnet pole is detected by a position detector (not shown) such as a Hall element in FIG. 5, and the center position of each magnet pole is located at 0 °, 90 °, 180 ° and 270 °. The U-phase and the V-phase stator iron cores at the positions of 30 °, 120 °, 210 °, and 300 ° facing each other are energized so that the magnetic pole surfaces facing the magnet magnetic poles have the same polarity. Therefore, the rotating disk 13
Is repelled in the direction of the rotation axis and is given a levitation force. Further, the V-phase stator iron core becomes the same pole as the rotor-side magnet magnetic pole and repels to generate a rotational force in the circumferential direction. Further, the W-phase stator iron core is de-energized, and even when de-energized, the armature iron core and the magnet magnetic poles are attracted to each other to de-energize and obtain a rotational force in the arrow direction. That is, the magnet magnetic pole N1 moves to the position of N1 'due to the repulsive force of the U phase, and the magnet magnetic pole N2 moves to the position of N2' due to the repulsive force of the V phase and the attraction force of the non-energized iron core of the W phase. . This energization pattern has a rotational position angle of 0 to 15
It is the same up to °. Therefore, when it reaches 15 °, the current is switched as shown in FIG.
Is a repulsive force (levitation force) in the rotation axis direction and a repulsive force in the rotation direction from the W-phase magnetic pole, and the magnet magnetic pole N1 'is a non-energizing attraction force from the V-phase magnetic pole and a repulsive force (rotational driving force) from the U-phase magnetic pole.
Is given. Therefore, if this is driven back every 15 °, the rotating disk can be continuously floated and driven to rotate. This relationship is due to the front surface (N pole) and back surface (S
The same).

By the brushless DC motor and its driving method of the present embodiment, the rotor magnetic pole and the magnetic pole of the stator iron core repel the same polarity to levitate and drive the rotor while giving a centripetal force in the axial and radial directions. It is possible. It is also possible to levitate by switching the energization pattern. Since stable static magnetic levitation and rotation can be obtained, a bearing is not required, cost is reduced, and the output shaft 10 can be rotated at high speed. Also, since the magnetic levitation principle is repulsive,
No special control other than motor drive control is required.

Next, the brushless D according to the second embodiment of the present invention.
FIG. 7 shows a sectional structure of the C motor, FIG. 8 shows a stator structure seen from the XX section, and FIG. 9 shows a rotor structure seen from the YY section. This motor is also suitable as a drive motor for rotating a polygon mirror or the like at a high speed, like the motor of the first embodiment. Also in the brushless DC motor of this embodiment, the rotor is levitated and driven only by the bearing in the auxiliary radial direction, by having both the rotational drive and the magnetic bearing function of non-repulsion control. .

A rotating disk 13 made of a non-magnetic material is fitted on the outer circumference of the output shaft 10, and a rotor magnet magnetic pole 14 is mounted on the outer circumference thereof. The rotor magnet magnetic pole 14 has an N pole on one side and an S pole on the opposite side, and the surface on the N pole side faces the N pole of the magnet pole of the stator pole 15.
Further, the output shaft 10 is supported at two places sandwiching the rotating disk by a shaft that is supported auxiliary in the radial direction and an auxiliary bearing 16 having a proper clearance, but in the thrust direction the weight of the rotating body is not supported. On the other hand, the levitation force is applied by the repulsive force between the rotor magnet magnetic pole and the stator magnet magnetic pole.

In this embodiment, the play in the thrust direction is large, but if two rotary discs and stators are provided and the rotary disc is sandwiched, the play in the thrust direction is regulated and becomes small. It is omitted here for the sake of simplicity.

The stator poles 15 are obtained by winding a stator winding around a magnet. Here, the rotor poles shown in FIG. 9 are replaced by the stator poles 12 shown in FIG. It is fixed at equal intervals on the circumference. In the stator, as shown in FIG. 8, three phases U, V, W are U1, V1, W1,
Four sets are lined up in the order of U2 ....

The stator base 17 may be made of a non-magnetic material, but a magnetic material may be used for the purpose of reducing the influence of an external magnetic field or the like. The main shaft 10 having the rotor 13 mounted therein is loaded in the recess on the stator base 17 having the stator magnetic poles 15 mounted thereon, and the cover 20 made of a non-magnetic material is fastened from above the main shaft 10 with bolts 21 to form a motor.

The stator pole 15 has an N pole on one side,
The opposite side is the S pole, and the surface on the N pole side is the N pole of the rotor pole.
It faces the pole side. At this time, the rotor magnetic pole center and the stator magnetic pole center do not coincide, and the repulsive force is always arranged so that the centripetal force acts in the radial direction. That is, the diameter of the circle connecting the centers of the rotor magnetic poles 14 and the diameter of the circle connecting the centers of the stator magnetic poles 15 are different as shown in FIG. As a result, a repulsive force is generated in the axial direction, so that the rotor 1 is uncontrolled.
It is possible to obtain a radial force in the direction in which the rotation axis of No. 3 is aligned with the central axis of the stator magnetic pole 15.

FIG. 10 shows the positional relationship between the rotor magnetic poles and the stator magnetic poles when the power is off. However, FIG. 10 shows YY of FIG.
Although the rotor and the stator magnetic poles are viewed from the cross section, the rotor magnetic pole positions overlap with each other and are difficult to understand. Therefore, the stator magnetic poles 15 are opened to the outside for convenience of description. When the rotor 13 is not energized, the rotor 13 floats from the stator due to the repulsive force between both magnetic poles, but it does not float stably without an auxiliary bearing. When the rotation angle is 0 ° when the rotor magnetic poles and the stator magnetic poles are radially overlapped with each other at the center position while the rotor is supported by the auxiliary bearings, the number of magnetic poles of the rotor and the stator of this embodiment is 8 and 12, respectively. As for the polar relationship, they stand still at a position of about 7.5 ° at which the repulsive force between the same poles stabilizes.

FIG. 11 is a diagram for explaining the principle of rotation from the time when the power is not supplied to the status shown in FIG. Figure 11
U1, U2, U3, U4 have the same U phase, V1,
For V2, V3, V4, the same V phase, W1, W2, W
3 and W4 are three-phase energization patterns in which in-phase W phases are connected so as to be supplied respectively. U phase of the present embodiment,
A wiring diagram of the V phase and the W phase is shown in FIG. In the energization method of the present embodiment, only two phases out of the three phases U, V and W are energized.
The phases are de-energized. Since the two phases that are further energized are DC pulse energized, when one is energized in the forward direction, the other is energized in the reverse direction.

According to the energization method of this embodiment, as shown in FIG. 13 or 14, the repulsive force is large in the forward direction, the repulsive force is in the non-energized state, and the repulsive force is small in the reverse direction. The amount changes. Incidentally, FIG. 13 shows a case where the current passing through the stator magnetic pole winding 12 is relatively small.
Indicates the case where the current passing through the stator magnetic pole winding 12 is relatively large. In this way, at least two phases generate repulsive force with respect to the rotor magnetic poles to generate three types of three types of magnetic force.

As shown in FIG. 12, the rotor rotation angle is from 0 ° to
During 15 °, the U-phase is energized in the forward direction and has a large repulsive force, the V-phase is in a non-energized repulsive force, and the W-phase is reversely energized and has a small repulsive force. In the relationship between the rotor magnetic poles and the stator magnetic poles in FIG. 11, the rotor rotation angle is 7.5.
The rotational force acts in the direction of the arrow in the figure, and the rotational force is in the same direction in the entire section of 0 ° to 15 °.

When the rotation angle of the rotor reaches 15 °, the energization switches to the state of the rotor rotation angle of 15 ° to 30 ° in FIG. 12, but a rotational force for driving the rotor in the same direction is generated. Similar rotational force is generated even when the rotation angle of the rotor is 30 ° to 45 °. In the case of the present embodiment, the rotor rotation angle is 45 ° and one cycle is performed, and the rotor makes one rotation (360 °) in four cycles.

The rotation angle of the rotor 13 may be detected by a non-contact rotation position angle sensor such as an optical sensor 19 as shown in FIG. 7, but in this embodiment, only two of the three phases are energized. Therefore, the rotation angle of the rotor 13 can be detected by using the counter electromotive voltage generated in the winding 12 of the remaining non-energized phase.

In the present embodiment, as described above, the energization pattern is switched according to the rotor rotation angle. However, even if the rotor rotation angle is not detected, the repulsive levitation force between the same poles is always generated. Therefore, even if you lose step, you can immediately return to the original pattern. Therefore, depending on the moment of inertia of the rotor, regardless of the rotation angle of the rotor, the rotation can be started up by gradually increasing the frequency.

In summary, according to the brushless DC motor and its driving method of the present embodiment, the repulsive action of the same poles of the rotor magnetic pole and the stator magnetic pole causes the rotor to levitate due to the repulsive force in the axial direction even when no power is supplied. It is possible to drive the levitation rotation while applying a repulsive force in the circumferential direction by energization. Also, the diameter of the rotor poles arranged on the circumference,
A radial centripetal force is created in the rotor by making the stator poles different in diameter from the circumference.
With the rotation, not only this magnetic centripetal force but also the gyro effect of the rotating body overlap, the centripetal force becomes large, and the radial bearing may be supplementary and simple, cost reduction, and the output shaft rotates at high speed. It is possible. Further, since the magnetic levitation principle is repulsive, no special control other than drive control of the motor is required, and the control system is simple.

In this embodiment, a magnet (permanent magnet) is used for the stator magnetic poles. However, even in the case of a coreless structure having only windings, similar to this embodiment, if repulsive excitation energization is performed, the same result is obtained. It goes without saying that such effects can be obtained.

In this embodiment, the rotor magnetic pole has 8 poles and the stator magnetic pole has 12 poles, but 2n rotor magnetic poles (n≥
2), it goes without saying that the same effect can be obtained even with 3n stator magnetic poles.

Further, in the present embodiment, both the rotor magnetic pole surface and the stator magnetic pole surface are flat surfaces, but it is needless to say that the same action and effect can be obtained even if both are arranged between the cylindrical surfaces. .

Further, as shown in FIG. 2, it is necessary to form an angle between the rotating disk magnetic pole surface and the stator magnetic pole surface with respect to the direction orthogonal to the axis.
This is to obtain the radial centripetal force (radial bearing force),
It goes without saying that there are various ways to attach the angle depending on the application.

[0045]

As described above, according to the present invention, it is possible to apply a centripetal force and a levitation force to the rotating disc while rotating the rotating disc fixed to the output shaft. According to such a brushless DC motor, it becomes possible to perform high-speed rotation drive and stop control of a scanner motor equipped with a polygon mirror, for example, without the need for supporting in the radial direction and the axial direction by an air bearing or a magnetic bearing.

[Brief description of drawings]

FIG. 1 is a plan view showing the structure of a brushless DC motor according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 to FIG. 6 are diagrams illustrating a method of driving a brushless DC motor according to an embodiment of the present invention, and FIG. 3 is an explanatory diagram showing a magnetic pole position relationship during stationary levitation.

FIG. 4 is a time chart of the same as above when a person is standing still.

FIG. 5 is an explanatory diagram showing a magnetic pole position relationship during rotational driving.

FIG. 6 is a time chart during rotation driving.

FIG. 7 is a sectional view showing the structure of a brushless DC motor according to a second embodiment of the present invention.

8 is a plan view of a stator magnetic pole as seen from the XX section of FIG. 7. FIG.

9 is a plan view of a rotor magnetic pole viewed from the YY cross section of FIG. 7. FIG.

FIG. 10 to FIG. 14 are views for explaining a driving method of the brushless DC motor according to the second embodiment of the present invention,
FIG. 10 is an explanatory diagram showing the positional relationship between the rotor magnetic poles and the stator magnetic poles during stationary levitation.

FIG. 11 is a diagram for explaining the principle of rotational driving, and an explanatory diagram showing the relationship between the magnetic pole strength of each magnetic pole of the stator with respect to the rotor magnetic poles.

FIG. 12 shows U, V, with respect to rotor position angles during rotational driving.
The time chart which shows the energization state of W phase.

FIG. 13 is an explanatory diagram showing changes in the amount of magnetic flux due to non-energization, forward energization, and reverse energization, showing a case where the energization current is relatively small.

FIG. 14 is an explanatory diagram showing changes in the amount of magnetic flux due to non-energization, forward energization, and reverse energization, showing a case where the energization current is relatively large.

FIG. 15 is an explanatory diagram showing a U-phase, V-phase, and W-phase connection state.

FIG. 16 is a cross-sectional view showing a magnetic pole arrangement (A) illustrating a conventional brushless DC motor, and (B) a time chart showing current switching.

[Explanation of symbols]

 11 Stator Iron Core 12 Stator Winding 13 Rotating Disc 14 Rotor Magnet 15 Stator Magnetic Pole N1, N2 ... Magnet Magnetic Pole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasushi Hisabe 4-1-1 Motofujisawa, Fujisawa-shi, Kanagawa Ebara Densan Co., Ltd.

Claims (6)

[Claims] 1. 2n sets (n ≧ 2) of magnetic poles of N and S poles are arranged on the plane of a rotating disc with the same poles arranged at equal intervals, and become the same poles as the magnetic poles on the rotating disc. The magnets on the rotating disk are arranged by arranging the magnetic poles of 3n stators that perform such three-phase energization so as to face the magnet magnetic poles on the rotating disk, and by energizing two phases of the three-phase stator magnetic poles. The magnetic pole is repelled and levitated, and the attracting force between the remaining one-phase non-energized stator and the magnet magnetic pole on the rotating disc causes the rotating disc to rotate, and a three-phase energization pattern is created according to the position of the magnetic pole. Brushless DC motor characterized by continuing rotation by switching. 2. The magnet magnetic poles arranged on one surface of the rotating disk are all N poles, and the magnetic poles arranged on the opposite surface are all S poles, and the magnet magnetic poles and the stator magnetic pole surface on the rotating disk rotate. 2. A brushless structure according to claim 1, further comprising a stator magnet structure which is inclined from a plane perpendicular to the disc axis and in which magnet pole faces on both sides of the rotating disc are sandwiched by stator iron cores so as to have the same poles. DC motor. 3. A three-phase energization pattern is used for rotation driving, and a three-phase all-phase direct current is energized to provide a repulsive stationary levitating energization pattern, and rotation / static control is performed by switching between both patterns. The brushless DC motor according to claim 2. 4. A set of 2n rotor magnetic poles having 2n sets of N and S poles (n ≧ 2) are arranged at equal intervals on the rotor circumference so that all surfaces facing the stator poles have the same pole. The stator magnetic poles, which are configured and opposed to the rotor magnetic poles, are magnetic poles formed by winding 3n windings and three-phase windings at equal intervals, and the stator windings have three different three-phase windings. A brushless DC motor characterized in that at least two-phase stator magnetic poles become the same poles as the rotor magnetic poles due to energization, repels the rotor, and the rotor is rotationally moved, and further three-phase energization patterns are switched to continuously rotate the motor. . 5. The stator magnetic pole is composed of a permanent magnet and a winding, or a permanent magnet, an iron core and a winding, and when there is no energization, the stator magnetic pole is all the same as the rotor magnetic pole, and all three phases are repulsive to the rotor magnetic pole. In addition, by energizing only two of the three phases in opposite directions, three types of energization are provided for each of the three phases, so that at least two-phase stator poles repel the rotor poles and the rotor is driven to rotate. The brushless DC motor is characterized by being continuously rotated by switching the energizing pattern. 6. The brushless DC according to claim 1, wherein the diameter of the circumference connecting the centers of the stator magnetic poles is larger or smaller than the diameter of the circumference connecting the centers of the rotor magnetic poles.
motor.