JP2005020931A - Commutator motor and motor driven blower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a commutator motor which can realize the reduction of mechanical vibrations caused by torque pulsation and the improvement of rectification performance. <P>SOLUTION: The AC commutator motor 1 is provided with a stator 3 composed of a stator iron core 33, which has a yoke 31 and a magnetic pole 32, and a field winding 5 wound to the magnetic pole 32, and a rotor 4 composed of an armature 43 in which an armature winding 42 is wound in eggplant-shaped slots S1-S12 formed to the outer peripheral part of an armature iron core 41 arranged between the magnetic poles 32, and a commutator 44 to which the armature winding 42 is connected. A single slit 32b open to the outside along in the opposing direction of the magnetic poles 32 is formed to the vicinity of the inner face 32a of the magnetic pole 32. Therefore, a magnetic bridge 32c is provided to the inside of the slit 32b in the vicinity of the center of the magnetic pole 32. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a commutator motor, and more particularly to a stator structure of an AC commutator motor used for a vacuum cleaner, a motor for an electric tool, and the like.
[0002]
[Prior art]
AC commutator motors used in vacuum cleaners, motors for electric tools, etc. are mainly composed of an annular stator and an armature disposed between magnetic pole portions formed facing the inner side of the stator. It is configured. This type of AC commutator motor is always required to be small, light, long brush life and low vibration. In order to reduce the vibration, it is desired to reduce the armature reaction (a phenomenon in which the magnetic field generated by the rotating armature affects the flow of the magnetic field passing through the magnetic pole portion of the stator). Yes.
[0003]
Conventionally, as a technique for reducing armature reaction, there has been proposed a structure in which a plurality of slits and slits penetrating inside and outside the stator are provided in the magnetic pole portion of the stator core (Patent Document). 1). Further, as another technique for reducing the armature reaction, a structure in which a slit having a shape different from the above technique is provided in the magnetic pole portion of the stator has been proposed (Patent Document 2). Furthermore, as another method for reducing the armature reaction, a structure has been proposed in which a slit that is not opened outside and inside the stator is provided at the center of the magnetic pole portion of the stator (Patent Document 3).
[0004]
[Patent Document 1]
Japanese Utility Model Publication No. 62-21744 (page 4, FIGS. 1 to 5)
[Patent Document 2]
JP-A-6-6943 (paragraph number [0021], FIG. 4)
[Patent Document 3]
Japanese Patent Laid-Open No. 7-123669 (paragraph numbers [0014], [0018], FIG. 1)
[0005]
[Problems to be solved by the invention]
By the way, with the advancement of FEM (finite element method) structural analysis software and computers in recent years, methods for predicting motor performance with high accuracy by magnetic field analysis have been developed. The characteristics of a motor rotating by applying a magnetic field have not been predicted so far. Therefore, the inventors of the present application analyzed the conventional structure as described above by using such a high-precision method for the analysis of the AC commutator motor, and the armature reaction was the main cause. It was derived that the state of the generated torque pulsation and the magnetic flux density distribution around the armature is not preferable. Therefore, it was necessary to develop a new shape of the slit that can make such a torque pulsation and magnetic flux density distribution desirable.
[0006]
Therefore, the object of the present invention is to reduce the mechanical vibration due to the torque pulsation and improve the rectification performance by forming a slit that contributes to reducing the torque pulsation and making the magnetic flux density distribution desirable. An object of the present invention is to provide a commutator motor that can be used.
[0007]
[Means for Solving the Problems]
According to one aspect of the present invention that solves the above-described problem, a stator core having an annular yoke portion and a magnetic pole portion formed to face the inside of the yoke portion, and a field wound around the magnetic pole portion A stator composed of magnetic windings, an armature in which armature windings are wound in a gap formed in an outer periphery of an armature core disposed between the magnetic pole portions, and the armature windings In the commutator motor provided with a commutator comprising a commutator to which the magnetic pole is connected, a single slit that opens outward in a direction in which the magnetic pole portion faces is provided near the center of the magnetic pole portion. By forming up to the vicinity of the inner surface of the portion, the magnetic bridge portion is provided inside the slit, so that torque pulsation is reduced and the magnetic flux density distribution is in a desirable state. Therefore, it is possible to reduce mechanical vibration due to torque pulsation and improve rectification performance.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a commutator motor according to the present invention will be described in detail with reference to FIGS.
FIG. 1 shows the structure of an AC commutator motor that is an embodiment of a commutator motor according to the present invention, and FIG. 2 shows the structure of a stator core. In FIG. 1, an AC commutator motor 1 is mainly composed of a substantially cylindrical housing 2, a stator 3 fixed to the housing 2, and a rotor 4 rotating with respect to the stator 3. Yes. The stator 3 is wound around each magnetic pole portion 32 and a stator core 33 having an annular yoke portion 31 having a substantially octagonal front view and a magnetic pole portion 32 formed to face the inside of the yoke portion 31. And field winding 5 to be formed. In the following description, the direction in which the two magnetic pole portions 32 and 32 face each other will be referred to as the vertical direction, and the direction perpendicular to the vertical direction and the axial direction of the rotor 4 will be described as the horizontal direction.
[0009]
As shown in FIG. 2, the yoke portion 31 includes an upper long side portion 31 a and a lower long side portion 31 b that are disposed to face each other in the vertical direction, and a left long side portion that is disposed to face the left and right directions. 31c and the right long side portion 31d, and four short side portions 31e,... Connecting these long side portions 31a to 31d are mainly configured, and the four short side portions 31e,. (See FIG. 1). In addition, a wide concave portion 31f that opens upward is formed in a substantially central portion of the upper surface of the upper long side portion 31a, and a wide concave portion that opens downward is formed in a substantially central portion of the lower surface of the lower long side portion 31b. 31 g is formed.
[0010]
The upper magnetic pole portion 32 extends downward (inward) from the upper long side portion 31a, and the left and right lower portions thereof extend in the left and right direction so as to cover the outer peripheral surface of the rotor 4 (see FIG. 1). It bulges out. Contrary to this, the lower magnetic pole portion 32 extends upward from the lower long side portion 31 b, and upwards to the left and right so that the left and right upper portions cover the outer peripheral surface of the rotor 4. Bulges. Further, the inner surface 32 a of each magnetic pole portion 32 is formed in a shape along the outer peripheral surface of the rotor 4. Furthermore, a single slit 32b that opens to the outside is formed in the vicinity of the inner surface 32a in the vertical direction near the center in the left-right direction of each magnetic pole portion 32. The slit 32b is formed so that its width (length in the left-right direction) is substantially constant. The width of the slit 32b may be set in any way, but is preferably equal to or greater than the thickness of the laminated steel plate (the member constituting the stator core 33) (for example, 0.5 mm or more).
[0011]
By forming the slit 32b up to the vicinity of the inner surface 32a in this way, a magnetic bridge portion 32c having a predetermined thickness is formed inside the slit 32b. Although the thickness of the magnetic bridge portion 32c can be changed as appropriate, it is desirable to form it thin. For example, when the stator core 33 is formed by laminating plate materials having a plate thickness of 0.35 mm, the minimum thickness of the magnetic bridge portion 32c is set to 0.35 mm, and the thickness is set to 0.35 mm to 2 mm. It is desirable to set within the range.
[0012]
As shown in FIG. 1, the rotor 4 has an armature in the slots (gap portions) S <b> 1 to S <b> 12 formed in the outer peripheral portion of the armature core 41 disposed between the two magnetic pole portions 32 and 32. The armature 43 is mainly composed of a winding 42 and a commutator 44 (see FIG. 3B) to which the armature winding 42 is connected. The armature core 41 has 13 teeth Te,... Having a substantially T-shaped cross-section by forming twelve slots S1 to S12 at a predetermined interval along the circumferential direction on the outer periphery thereof. -Has a shape formed at predetermined intervals along the circumferential direction. Further, a shaft hole 41 a into which a shaft (not shown) is fitted is formed in the central portion of the armature core 41.
[0013]
Further, as shown in FIG. 3B, the armature winding 42 has a plurality of inner sides whose both ends are connected to any two of the 24 commutator pieces P1 to P24 constituting the commutator 44. The coil 42a and the outer coil 42b are configured. Specifically, for example, the inner coil 42a, one end of which is connected to the commutator piece P23, is wound so as to pass through a pair of the first egg shaped slot S1 and the sixth egg shaped slot S6. The end is connected to the commutator piece P24 adjacent to the commutator piece P23. The outer coil 42b, one end of which is connected to the commutator piece P24, is wound so as to pass through the first egg-shaped slot S1 and the sixth egg-shaped slot S6, and the other end thereof is the commutator piece. It is connected to the commutator piece P1 adjacent to P24. Similarly, the inner coil 42a and the outer coil 42b passing through the other pair of slots (S2, S7), (S3, S8),..., (S12, S5) are also connected to the pair of commutator pieces ( P1, P2), (P2, P3),... (P22, P23) are sequentially connected.
[0014]
Next, the results obtained by simulating with the FEM structural analysis software using the AC commutator motor 1 configured as described above and the AC commutator motor having another structure as an analysis model will be described. Initially, with reference to FIG. 3, the conditions which calculated the torque of the motor by giving an alternating magnetic field are shown. Here, FIG. 3A shows a mesh model used for analysis and calculation conditions. FIG. 3B shows a connection diagram of the armature winding in a state where the substantially cylindrical armature is developed on a plane. FIG. 3C shows an example of the input current pattern. FIG. 3D shows a change in current flowing through each coil.
[0015]
As shown in FIG. 3A, first, the stator core 33, the field winding 5, the armature core 41, and the armature winding 42, which are components of the AC commutator motor 1, are combined. It is divided into a plurality of elements so that the number is 25402E. As shown in FIG. 3B, the wiring conditions around the commutator 44 include connecting the coils 42a and 42b constituting the armature winding 42 to the commutator 44 under the above-described conditions, The two brushes 6 are contacted so as to straddle any three of the commutator pieces P1 to P24. The two brushes 6 are provided so as to face each other in the radial direction of the armature 43 having a substantially cylindrical shape. Further, as shown in FIG. 3 (c), the condition of the alternating current applied to the alternating current commutator motor 1 is that the maximum absolute value of the current value is 6A (ampere), and the period is 3600 ° (deg). It has become. Here, in this simulation, since the rotation speed of the motor is set to 30000 rpm, in other words, the cycle of the alternating current is 50 Hz (Hertz).
[0016]
Incidentally, in the AC commutator motor 1, an AC current is given in the order of the field winding 5 on the stator 3 side, the brush 6, the commutator 44, the armature winding 42 on the armature 43 side, and the armature 43 side. This is a motor that rotates by controlling the current in the direction in which torque is generated by switching between plus and minus of the current flowing through the arm 6 every half rotation of the armature 43 by the brush 6. Therefore, when this motor is rotated counterclockwise at 30000 rpm and a current of 50 Hz is given as an input, one cycle of the current of 50 Hz is 0.02 seconds. Therefore, during this 0.02 seconds, the motor rotates 10 times. (3600 °). Further, as shown in FIG. 3D, in each of the coils 42 a and 42 b of the armature 43, each time the armature 43 makes a half rotation (180 °), each coil 42 a, The positive and negative of the alternating current supplied to 42b are mechanically switched, and the positive and negative of the current are electrically switched every 0.01 second (1800 °) which is a half cycle of the alternating current.
[0017]
Subsequently, magnetic flux density distribution and output torque calculation results calculated under the above conditions are shown in FIGS. 4 shows a motor structure showing Comparative Example 1, FIG. 5 shows a motor structure showing Comparative Example 2 provided with a slit that opens only inside, and FIG. 6 shows a motor structure showing Comparative Example 3 with slits from the inside to the outside. Reference numeral 7 denotes a structure in which slits are formed only on the outside of the present invention (a magnetic bridge is formed on the inside). FIG. 4A shows the slit shape, FIG. 5B shows the magnetic flux lines, FIG. 5C shows the gap magnetic flux density at the maximum torque, and FIG. 4D shows the output torque calculation result.
[0018]
As shown in FIG. 4A, the motor structure of Comparative Example 1 has a structure in which no slit is formed in the magnetic pole portion 32. In the following description, the right axis among the axes drawn from the central axis of the armature 43 in the vertical and horizontal directions is set to 0 deg, and the other axes are set to 90, 180, and 270 deg in order counterclockwise.
[0019]
The FEM analysis result of Comparative Example 1 shows that the shape of the magnetic pole portion 32 is symmetric about the axis of 90 deg, whereas the magnetic flux density distribution of the gap (gap between the stator 3 and the armature 43) is as shown in FIG. As shown in (c), the left and right of 90 deg, that is, between 0 and 90 deg and between 90 and 180 deg, is not symmetrical. This occurs due to the effect of magnetizing and demagnetizing due to the effect of the armature reaction. Incidentally, the left side of the upper magnetic pole portion 32 is a demagnetization side, and the right side is a magnetization side. In addition, as can be seen from FIG. 4B, the degree of influence thereof, when attention is paid to the upper magnetic pole portion 32 of the stator 3, the magnetic flux density on the right side of the magnetic pole portion 32 increases due to the inflow of magnetic flux from the left side to the right side. You can see that Due to this influence, the output torque pulsates and becomes a torque waveform as shown in FIG. 4D. The average torque is 0.523 N · m (Newton meter), whereas the maximum value of torque pulsation is 0.16 N.・ It becomes large with m.
[0020]
As shown in FIG. 5A, the motor structure of Comparative Example 2 has a structure in which slits 71 opening inward are formed in the magnetic pole portion 32 along the vertical direction. The structure of Comparative Example 2 was also analyzed by FEM as described above. As a result of calculation under the same conditions except for the slit 71 such as the current condition, the results shown in FIGS. By providing the slit 71, as shown in FIG. 5C, the gap magnetic flux density in the vicinity of 90 deg and 270 deg is reduced. Further, according to FIG. 5B, in the magnetic pole portion 32 on the upper side of the stator 3, the inflow of the magnetic flux from the left side to the right side is somewhat suppressed. It can be seen that the magnetic flux density on the right side of FIG. Further, as the magnetic flux density of the magnetic pole portion 32 on the left side (demagnetization side) slightly increases, the average torque increases by about 0.7% with respect to the comparative example 1, and the torque pulsation also decreases to 0.13 N · m. However, it can be seen that the reduction rate with respect to torque pulsation in Comparative Example 1 is as small as 0.83%.
[0021]
As shown in FIG. 6A, the motor structure of Comparative Example 3 has a structure in which slits 72 that open inward and outward (up and down) are formed in the magnetic pole portion 32 along the vertical direction. The structure of Comparative Example 3 was also analyzed by FEM as described above. As a result of calculation under the same conditions except for the slit 72 such as the current condition, the results shown in FIGS. 6B to 6D were obtained.
[0022]
By providing the slit 72, as shown in FIG. 6C, the gap magnetic flux density in the vicinity of 90 deg and 270 deg is greatly reduced. Further, according to FIG. 6B, inflow of magnetic flux from the left side to the right side is blocked at the magnetic pole portion 32 on the upper side of the stator 3. As a result, the magnetic flux density on the left side (demagnetization side) of the magnetic pole portion 32 is increased and the average torque is also improved by 0.7%, but the torque pulsation is as large as 0.17 N · m.
[0023]
FIG. 7A shows a calculation result of a structure employing the slit 32b according to the present invention. Since the magnetic bridge portion 32c made of a silicon steel plate or the like formed on the inner side of the slit 32b is magnetically saturated, as shown in FIG. 7C, the vicinity of 90 deg and 270 deg is the same as the slit 71 and slit 72 described above. The gap magnetic flux density has fallen. Further, the magnetic saturation of the magnetic bridge portion 32c and the slit 32b block the flow of magnetic flux from the left side to the right side in the magnetic pole portion 32 on the upper side of the stator 3, as shown in FIG. 7B. As a result, the magnetic flux density on the left side (demagnetization side) of the magnetic pole portion 32 is increased, and the average torque is greatly improved (2.7%) as shown in FIG. Further, since the change in the magnetic flux density is reduced (see FIG. 7C), it can be seen that the torque pulsation is greatly reduced to 0.03 N · m, and the reduction rate of the torque pulsation is increased to 27%.
[0024]
Next, comparison of torque pulsation is shown in FIG. Compared to the structure of the normal AC commutator motor (Comparative Example 1), the structure of Comparative Example 2 provided with the slit 71 also shows the effect of reducing torque pulsation, but in the structure of providing the slit 32b outside the present invention, Torque pulsation can be significantly reduced as compared with Comparative Example 2 and about 1/5 or less than Comparative Example 1. Up until now, this has not been clearly confirmed in the prototype evaluation due to manufacturing errors and measurement difficulties, but this was confirmed for the first time by applying FEM analysis, which is a highly accurate calculation method. It is.
[0025]
When the torque pulsation is large, the vibration of the rotor 4 becomes large, so that the commutation action by the commutator 44 and the brush 6 is complemented, the spark from the brush 6 becomes large, and a short circuit flows between the brush 6-coils 42a and 42b. As the current increases, the stray loss increases, so that the performance deteriorates and the brush life is shortened. However, by providing the slit 32b as in the present invention, the torque pulsation is reduced by 80%. As a result, the vibration of the rotor 4 is reduced, the spark from the brush 6 is reduced, the performance is improved, and the brush life is extended. is there.
[0026]
According to the above, the following effects can be obtained in the present embodiment.
A single slit 32b that opens outward is formed in the vicinity of the central portion of the magnetic pole portion 32 of the stator core 33, and a magnetic bridge portion 32c is provided on the inner side of the slit 32b. Since the flow is adjusted, the influence of the armature reaction can be reduced. Furthermore, according to this structure, the torque pulsation is reduced and the magnetic flux density distribution is in a desirable state based on the simulation result, so that mechanical vibration due to the torque pulsation is reduced and the rectification performance is improved. be able to. Incidentally, the present invention has found a structure capable of improving commutation and increasing torque as a result of predicting the generated torque by applying an alternating magnetic field to derive the magnetic flux density of the motor core and gap portion by calculation.
[0027]
As mentioned above, this invention is implemented in various forms, without being limited to the said embodiment. Other embodiments will be described below.
[0028]
The AC commutator motor 1 may be used for any electric device, but for example, when used as a motor of an electric blower that is a drive system of a vacuum cleaner, the following effects are exhibited. As shown in FIG. 9, the electric blower 8 is mainly composed of a fan 81 and an AC commutator motor 1. Here, in general, in the electric blower, in order to reduce the size of the material to be used from the viewpoint of environmental problems, it is necessary to increase the rotational speed of the motor. However, if the torque pulsation is large, the vibration is increased and the rotational speed is increased. There is a problem that can not be up. On the other hand, in the present invention, the torque pulsation is reduced, so that the number of rotations can be increased, thereby reducing the size and weight, thereby improving the environmental problem.
[0029]
FIG. 10 shows an application example of a structure in which a slit that opens to the outside is provided. FIG. 10A shows a structure in which the width of the magnetic pole portion 32 is changed on the left and right sides of the slit 32b. In order to reduce the influence of the armature reaction, it is necessary to consider the magnetic flux density balance on the magnetizing side and the demagnetizing side. Therefore, the method of adjusting the width (cross-sectional area) of the magnetic pole portion 32 is effective. That is, when the AC commutator motor 1 is driven, the width of the magnetic pole part 32 that is the demagnetization side (refers to the left side of the upper magnetic pole part 32 and the right side of the lower magnetic pole part 32 in the figure) It is desirable that it be formed larger than the width of the magnetic pole portion 32 (referring to the right side of the upper magnetic pole portion 32 and the left side of the lower magnetic pole portion 32 in the figure). According to this structure, since the width of the magnetic pole portion 32 on the demagnetization side is large, many magnetic lines of force flow on the demagnetization side, and the magnetic flux density balance between the demagnetization side and the demagnetization side is made appropriate. Can do. Further, as shown in FIG. 10B, a structure in which the slit 32d is provided inclined from the central axis (vertical direction) of the magnetic pole portion 32 is also considered effective.
[0030]
FIG. 11 shows a structure in which a non-magnetic material is inserted as a filler into the slit 32b. In this way, the mechanical strength can be ensured by forming the structure MB such as an organic material or a metal material, which is a non-magnetic material, by bonding, injection, press fitting, or the like in the slit 32b.
[0031]
FIG. 12 shows an example of a shape in which the slit shape is enlarged and the magnetic bridge portion 32c is formed longer. Specifically, the slit 32e is formed so as to widen from the inner side toward the outer side, and the width of the inner part thereof is formed to be larger. By forming the slit 32e in this manner, the magnetic pole portion 32 is divided so as to be independent on the left and right, so that the flow of magnetic flux is prevented from being biased to the left or right, and the same effect as the slit 32b of the present invention. Can be obtained.
[0032]
【The invention's effect】
According to the present invention, it is possible to reduce mechanical vibration due to torque pulsation and improve rectification performance.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a structure of an AC commutator motor that is an embodiment of a commutator motor according to the present invention.
2 is a perspective view showing the structure of the stator core shown in FIG. 1. FIG.
FIG. 3 is a cross-sectional view (a) showing a mesh model used for analysis, a connection diagram (b) showing a connection state of armature windings in a state where the armature is developed on a plane, and an example of an input current pattern; (C) which shows this, and (d) which shows the change of the electric current which flows through each coil.
4A is a cross-sectional view showing the motor structure of Comparative Example 1, FIG. 4B is a cross-sectional view showing the flow of magnetic flux lines, FIG. 4C is a view showing the gap portion magnetic flux density at the maximum torque, and FIG. It is a figure (d) which shows a calculation result.
5A is a cross-sectional view showing the motor structure of Comparative Example 2, FIG. 5B is a cross-sectional view showing the flow of magnetic flux lines, FIG. 5C is a diagram showing gap part magnetic flux density at the maximum torque, and FIG. It is a figure (d) which shows a calculation result.
6A is a cross-sectional view showing the motor structure of Comparative Example 3, FIG. 6B is a cross-sectional view showing the flow of magnetic flux lines, FIG. 6C is a view showing the gap portion magnetic flux density at the maximum torque, and FIG. It is a figure (d) which shows a calculation result.
FIG. 7 is a cross-sectional view (a) showing the motor structure according to the present embodiment, a cross-sectional view (b) showing the flow of magnetic flux lines, a view (c) showing the gap portion magnetic flux density at the maximum torque, and an output. It is a figure (d) which shows a torque calculation result.
FIG. 8 is a diagram showing a maximum value of torque pulsation in each motor structure.
FIG. 9 is a cross-sectional view showing a state in which the motor according to the present invention is applied to an electric blower.
10A and 10B are views showing a motor structure according to another embodiment of the present invention, a cross-sectional view showing a structure in which the slit is shifted from the center of the magnetic pole part, and a cross-section showing a structure formed by inclining the slit. FIG.
FIG. 11 is a cross-sectional view showing a form in which a slit is filled with a filler.
FIG. 12 is a cross-sectional view showing a form in which slits are formed so as to widen from the inside toward the outside.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 AC commutator motor 2 Housing 3 Stator 31 Yoke part 32 Magnetic pole part 32a Inner surface 32b Slit 32c Magnetic bridge part 33 Stator iron core 4 Rotor 41 Armature iron core 42 Armature coil | winding 43 Armature 44 Commutator 5 Field winding Lines S1 to S12 Egg slot (gap)

Claims (7)

A stator core comprising a stator core having an annular yoke portion and a magnetic pole portion formed facing the inside of the yoke portion, and a field winding wound around the magnetic pole portion;
A rotation composed of an armature in which an armature winding is wound in a gap formed in an outer peripheral portion of an armature core disposed between the magnetic pole portions, and a commutator to which the armature winding is connected. A commutator motor including a child,
In the vicinity of the center of the magnetic pole part, a magnetic slit is provided on the inner side of the slit by forming a single slit that opens to the outside along the direction in which the magnetic pole part is opposed to the inner surface of the magnetic pole part. A commutator motor characterized by that. The commutator motor according to claim 1, wherein the magnetic bridge portion has a thickness of 0.35 mm to 2 mm. The commutator motor according to claim 1, wherein the slit is filled with a filler that is a non-magnetic material. The commutator motor according to any one of claims 1 to 3, wherein the slit is formed so as to expand from the inside toward the outside. 5. The commutator motor according to claim 1, wherein the slit is formed to be inclined with respect to a direction in which the magnetic pole portions are opposed to each other. In the commutator motor according to any one of claims 1 to 5,
Of the magnetic pole portions divided around the slit, the width of the magnetic pole portion on the demagnetization side when the commutator motor is driven is formed larger than the width of the magnetic pole portion on the magnetization side. A commutator motor characterized by An electric blower using the commutator motor according to any one of claims 1 to 6 as a motor of an electric blower that is a drive system of a vacuum cleaner.

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