JP6020744B2 - Commutator motor, electric blower, vacuum cleaner, and commutator motor manufacturing method - Google Patents

Description

  The present invention relates to a commutator motor, an electric blower, a vacuum cleaner, and a commutator motor manufacturing method.

  There is known an electric blower in which a blower unit and a motor are integrated. The electric blower is mounted on a vacuum cleaner or the like. Generally, the electric blower is used at a high speed rotation of 30000-45000 rotations per minute. Therefore, an electric blower uses a commutator motor including a stator having two magnetic poles and field windings, and a rotor inside the stator and having armature windings and commutators.

  In a conventional electric blower, the stator core has a substantially square frame shape, and includes substantially crescent-shaped magnetic poles projecting inwardly from two sides facing each other by 180 °. The magnetic flux flows from the surface of the rotor core across the gap between the opposing surfaces of the stator core and the rotor core, enters the tip of one magnetic pole, splits into two hands at the back of the magnetic pole, merges through the yoke to the back of the other magnetic pole, The rotor core enters from the tip of the magnetic pole across the gap between the opposing surfaces of the stator core and the rotor core, crosses the rotor core in the direction connecting the two magnetic poles, returns to the initial position, and goes around. The yokes are the two sides of the stator core without the magnetic poles. In the base part of the magnetic pole and the corner part of the frame shape, the magnetic flux gradually changes its direction while drawing an arc. That is, in the conventional stator core, the direction of the magnetic flux varies depending on the location in the stator core. Therefore, as a material for the stator core, a non-oriented electrical steel sheet whose magnetic properties do not have directionality is usually used. That is, the stator core is formed by laminating and fixing the non-oriented electrical steel sheets punched out by pressing in the axial direction of the motor. The rolling direction of the grain-oriented electrical steel sheet having magnetic properties is called the easy magnetization direction, and the magnetic characteristics are superior to the non-oriented electrical steel sheet. On the other hand, the direction perpendicular to the rolling direction of the grain-oriented electrical steel sheet is inferior in magnetic properties to the non-oriented electrical steel sheet. When a directional electrical steel sheet is used for a conventional stator core, the efficiency of the magnetic circuit is increased in a part where the direction of magnetic flux and the easy magnetization direction are compared with the case where a non-oriented electrical steel sheet is used, but the part where they do not match Then the efficiency of the magnetic circuit decreases. As a result, the total efficiency of the magnetic circuit decreases and the motor efficiency decreases. Therefore, it has been difficult to adopt a grain-oriented electrical steel sheet for a conventional stator core.

  Patent Document 1 listed below discloses a technique in which a plurality of blocks made of laminated grain-oriented electrical steel sheets are combined to form a stator core, and the direction of magnetic flux and the direction of easy magnetization are substantially matched for each block.

Japanese Unexamined Patent Publication No. 2010-093945

  The technique of Patent Document 1 has the following problems. At the base part of the magnetic pole of the stator core and the corner part of the frame shape, the magnetic flux gradually changes its direction while drawing an arc. In these portions, the direction of the magnetic flux and the direction of easy magnetization do not match sufficiently. For this reason, the technique of Patent Document 1 cannot sufficiently improve the efficiency of the magnetic circuit. Further, on the joint surface of the block, that is, the split surface of the stator core, distortion due to the stamping of the grain-oriented electrical steel sheet in the press exists in the regions on both sides with the split surface as a boundary, and the magnetic characteristics deteriorate in that region. In the technique of Patent Document 1, the split surfaces of the stator core exist at the base portion of the magnetic pole and the corner portion of the frame shape. Therefore, since all the magnetic flux crosses the dividing surface of the stator core, it is affected by the efficiency reduction in the regions on both sides of the dividing surface with low magnetic characteristics. In the technique of Patent Document 1, it is necessary to divide the stator core into more blocks in order to sufficiently match the direction of magnetic flux and the direction of easy magnetization. However, the more the stator core is divided into more blocks, the more the number of divided surfaces of the stator core increases. Therefore, the stator core is further affected by the efficiency reduction due to the divided surfaces of the stator core, and the efficiency of the magnetic circuit cannot be sufficiently improved.

  The present invention has been made to solve the above-described problems, and a commutator motor and an electric motor capable of sufficiently improving the efficiency of a magnetic circuit of a commutator motor having a stator core using a directional electromagnetic steel sheet. It aims at providing a blower, a vacuum cleaner, and a commutator motor manufacturing method.

  A commutator motor of the present invention includes a stator having a stator core and a field winding, and a rotor having an armature winding and disposed inside the stator, and the stator core has a longitudinal direction as an easy magnetization direction. And the normal of the surface of the grain-oriented electrical steel sheet is perpendicular to the rotation axis of the rotor, and the stator core includes the first stator core and The number of layers of grain-oriented electrical steel sheets to be laminated decreases as it is divided into second stator cores and closer to the core dividing surface.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to fully improve the efficiency of the magnetic circuit of the commutator motor which has a stator core using a grain-oriented electrical steel sheet.

It is a longitudinal cross-sectional view which shows the electric blower of Embodiment 1 of this invention. It is sectional drawing which looked at the principal part of the commutator motor of Embodiment 1 of this invention from the blower part side of the rotating shaft direction of the rotor. It is the figure which extracted only the stator core from FIG. It is an example of the magnetic flux diagram of the commutator motor of Embodiment 1 of this invention calculated | required by the electromagnetic field analysis. It is a schematic diagram showing a flyer winding machine which is an example of an automatic machine for performing aligned winding of field windings. It is sectional drawing which looked at the principal part of the commutator motor of Embodiment 2 of this invention from the blower part side of the rotating shaft direction of the rotor. It is the figure which extracted only the stator core from FIG. It is an example of the magnetic flux diagram of the commutator motor of Embodiment 2 of this invention calculated | required by the electromagnetic field analysis. It is a schematic diagram which shows the example of the cutting process of the commutator motor manufacturing method of Embodiment 3 of this invention. It is a schematic diagram which shows the example of the bending process of the commutator motor manufacturing method of Embodiment 3 of this invention. It is sectional drawing which shows the vacuum cleaner of Embodiment 4 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted. In addition, the present invention includes all combinations of the embodiments described below.

Embodiment 1 FIG.
FIG. 1 is a longitudinal sectional view showing an electric blower according to Embodiment 1 of the present invention. As shown in FIG. 1, the electric blower 1 of the first embodiment includes a blower unit 2 that generates suction force and a commutator motor 3 that drives the blower unit 2. The electric blower 1 can be applied to a vacuum cleaner, for example.

  The blower unit 2 includes a fan 4 having a plurality of blades and a fan guide 5 that covers the fan 4. The fan guide 5 guides the air flowing along with the rotation of the fan 4 to the inside of the commutator motor 3. This flowing air is discharged from an opening (not shown) provided in the frame 6 while cooling the commutator motor 3 that generates heat during operation.

  The commutator motor 3 includes a stator 7 fixed inside a cup-shaped or cylindrical frame 6, and a rotor 8 disposed facing the inside of the stator 7 via a gap 20. The stator 7 serves as a field. The rotor 8 is rotatably supported and serves as an armature. A part of the commutator motor 3 that does not fit inside the frame 6 protrudes outward from an opening or notch formed in the frame 6.

  The stator 7 includes a stator core 9 formed by laminating and fixing a plurality of directional electromagnetic steel sheets, and a field winding 10 wound around the stator core 9 via an insulating member 24. A magnetic field is generated inside the stator 7 by passing a current through the field winding 10.

  The rotor 8 is separated from the rotor core 12 by a shaft 11 disposed in the center, an annular rotor core 12 fixed around the shaft 11, an armature winding 17 wound around the rotor core 12 via an insulating member 22, and the rotor core 12. And a commutator 13 fixed around the shaft 11 at a certain position. The rotor core 12 is formed by laminating and fixing a plurality of electromagnetic steel plates. The shaft 11 is supported by the frame 6 via bearings 14 and 15. Thereby, the rotor 8 is freely rotatable with respect to the frame 6. One bearing 14 located on the blower unit 2 side is accommodated in a bracket 21 provided so as to cross-link across the opening of the frame 6. The other bearing 15 located on the side opposite to the blower unit 2 side is housed in the bottom of the frame 6.

  The fan 4 is fixed to the end portion 16 of the shaft 11 on the blower portion 2 side. As the rotor 8 rotates, the fan 4 is driven to rotate. The starting end or end of winding of the plurality of coils constituting the armature winding 17 and the terminal or end of winding end are electrically connected to the segment 18 of the commutator 13 by a method such as fusing or heat caulking. The pair of brushes 19 are held by the frame 6, pressed against the commutator 13 by a spring, and slidably contact the commutator 13. The brush 19 is connected to a power source (not shown) and supplies a current, that is, an armature current to the armature winding 17 via the commutator 13. The field winding 10 is connected in series with the armature winding 17 and supplies current to the field winding 10 from the same power source. Rotational torque is generated in the rotor 8 by the magnetic field generated by the stator 7 and the armature current. In order to make the rotation direction of the rotor 8 constant, the armature winding 17 and the segment 18 are connected so that the coil through which the armature current flows is switched in accordance with the phase of the rotor 8.

  FIG. 2 is a cross-sectional view of the main part of the commutator motor 3 according to the first embodiment as viewed from the blower part 2 side in the rotation axis direction of the rotor 8. FIG. 3 is a diagram in which only the stator core 9 is extracted from FIG. The rotation direction of the rotor 8 can be set by a combination of the connection between the armature winding 17 and the segment 18. The rotation direction of the rotor 8 is determined from the direction of the blades of the blower unit 2. In the first embodiment, it is assumed that the rotation direction of the rotor 8 is counterclockwise, that is, counterclockwise in FIG.

  As shown in FIGS. 2 and 3, the stator core 9 has an annular shape when viewed from the rotation axis direction of the rotor 8. The stator core 9 is divided into a first stator core 9A and a second stator core 9B, with two core division surfaces 25a and 25b as a boundary. The first stator core 9A and the second stator core 9B are substantially C-shaped. When viewed from the rotational axis direction of the rotor 8, the core dividing surfaces 25 a and 25 b are located at positions shifted rearward in the rotational direction of the rotor 8 with respect to the magnetic pole center line of the stator core 9. In the first embodiment, the core split surfaces 25a and 25b are in the vicinity of the direction perpendicular to the electrical neutral axis during the rated operation of the commutator motor 3. In the following description, the electric neutral shaft at the rated operation of the commutator motor 3 is simply referred to as “electric neutral shaft”. In the first embodiment, the core dividing surfaces 25 a and 25 b are perpendicular to the electrical neutral axis and are in the position of the plane passing through the center of the rotor 8 or the vicinity thereof. The core dividing surfaces 25a and 25b are located behind the magnetic pole center line in the rotation direction of the rotor 8. The core dividing surface is at a position obtained by rotating the magnetic pole center line by an acute angle in the direction opposite to the rotation direction of the rotor 8. This means that there are 25a and 25b.

  The first stator core 9A includes a magnetic pole portion 91A located on the core dividing surface 25a side, a magnetic pole portion 92A located on the core dividing surface 25b side, and a winding mounting portion 93A located between the magnetic pole portions 91A and 92A. Have. The second stator core 9B includes a magnetic pole portion 91B located on the core dividing surface 25b side, a magnetic pole portion 92B located on the core dividing surface 25a side, and a winding mounting portion 93B located between the magnetic pole portions 91B and 92B. Have. The magnetic pole portions 91 </ b> A, 92 </ b> A, 91 </ b> B, 92 </ b> B have an arc shape centered on the rotation axis of the rotor 8. The field winding 10 is wound around the winding mounting portion 93A of the first stator core 9A and the winding mounting portion 93B of the second stator core 9B via the insulating member 24. The armature winding 17 wound around the rotor core 12 via the insulating member 22 is prevented from coming off by a wedge 23.

  As shown in FIG. 3, the magnetic pole portion 91 </ b> A of the first stator core 9 </ b> A and the magnetic pole portion 92 </ b> B of the second stator core 9 </ b> B form one magnetic pole 26 a of the stator core 9. The magnetic pole portion 92A of the first stator core 9A and the magnetic pole portion 91B of the second stator core 9B form the other magnetic pole 26b of the stator core 9. The inner peripheral sides of the magnetic poles 26a and 26b face the rotor 8 with a predetermined gap 20 therebetween. A straight line connecting the center of the length of the magnetic pole 26a in the circumferential direction around the rotation axis of the rotor 8 and the center of the length of the magnetic pole 26b in the circumferential direction around the rotation axis of the rotor 8 is a magnetic pole center line It corresponds to. In the first embodiment, the core dividing surfaces 25a and 25b are inclined with respect to the magnetic pole center line. However, it is not limited to such a configuration, and the core dividing surfaces 25a and 25b may be positioned at the magnetic pole center line.

  The first stator core 9A and the second stator core 9B have a shape that swells outward at a position substantially perpendicular to the magnetic pole center line. Due to the swollen shape, winding mounting portions 93A and 93B around which the field winding 10 is wound are formed. The winding mounting portions 93A and 93B are located farther from the rotating shaft of the rotor 8 than the magnetic pole portions 91A, 92A, 91B, and 92B. A region 30 is formed between the winding mounting portion 93 </ b> A and the outer periphery of the rotor 8, and a region 31 is formed between the winding mounting portion 93 </ b> B and the outer periphery of the rotor 8. The field winding 10 is mounted by a toroidal winding around the winding mounting portion 93A using the region 30 and the region 32 on the opposite side of the region 30 across the winding mounting portion 93A. Similarly, the field winding 10 is mounted by a toroidal winding around the winding mounting portion 93B using the region 31 and the region 33 on the opposite side of the region 31 across the winding mounting portion 93B. .

  The winding direction of the field winding 10 is indicated by a dot mark and a cross mark in FIG. The dot mark indicates the current flow from the back of the paper to the front, and the cross mark indicates the current flow from the front of the paper to the back. The winding direction of the field winding 10 may be a combination of directions opposite to those in the example of FIG. In addition to the toroidal winding, the field winding 10 may be wound around the region 30 from the region 30 to the region 31 while avoiding interference with the rotor 8, and the region 31 on the opposite side of the rotor 8 in the rotation axis direction. There is also a method of avoiding interference with the rotor 8 and returning to the area 30 by detouring and repeating this by a predetermined number of turns. This method has an advantage that it is not necessary to use the regions 32 and 33 as compared with the toroidal winding. On the other hand, this method has a demerit that it is difficult to arrange windings and that the winding length is long due to the detour shape of the coil end to avoid interference with the rotor 8. For this reason, toroidal winding is usually a better choice.

  The magnetic flux generated by the field winding 10 is in a direction along the magnetic pole center line between the magnetic poles 26a and 26b. The electrical neutral axis is an axis perpendicular to the direction of the combined magnetic flux of the magnetic flux generated by the field winding 10 and the magnetic flux generated by the armature winding 17. The direction perpendicular to the electrical neutral axis is shifted backward in the rotational direction of the rotor 8 with respect to the magnetic pole center line. Accordingly, the angle between the positions of the two core dividing surfaces 25a and 25b and the magnetic pole center line is set by the balance of magnetic flux generated by the field winding 10 and the armature winding 17, respectively. Specifically, it may be determined using the result of electromagnetic field analysis or prototype evaluation.

  The stator core 9 is configured by laminating and fixing a plurality of bent directional electromagnetic steel sheets 94. The longitudinal direction of the band-shaped grain-oriented electrical steel sheet 94 is the easy magnetization direction. Moreover, the normal line of the surface of each directional electromagnetic steel sheet 94 to be laminated is perpendicular to the rotation axis of the rotor 8. That is, the direction in which the directional electromagnetic steel sheets 94 are stacked is substantially perpendicular to the longitudinal direction of the magnetic path of the stator core 9 when viewed from the rotational axis direction of the rotor 8. Moreover, the easy magnetization direction of the grain-oriented electrical steel sheet 94 is a direction along the magnetic path. The thickness of the laminated directional electromagnetic steel sheets 94 corresponds to the magnetic path width (width of the magnetic pole and yoke) of the stator core 9 when viewed from the direction of the rotation axis of the rotor 8. Further, the width of the belt-shaped directional electromagnetic steel sheet 94, that is, the length in the short side direction, corresponds to the length of the stator core 9 in the direction of the rotation axis of the rotor 8.

  Each of the plurality of strip-shaped directional electromagnetic steel plates 94 constituting the first stator core 9A is continuous from the magnetic pole portion 91A to the magnetic pole portion 92A via the winding mounting portion 93A. Similarly, each of the plurality of strip-shaped directional electromagnetic steel plates 94 constituting the second stator core 9B is continuous from the magnetic pole portion 91B to the magnetic pole portion 92B via the winding mounting portion 93B.

  FIG. 4 is an example of a magnetic flux diagram of the commutator motor 3 of the first embodiment obtained by electromagnetic field analysis. As shown in FIG. 4, the magnetic flux lines of the stator core 9 are along the longitudinal direction of the directional electromagnetic steel sheet 94, that is, the easy magnetization direction, except for the vicinity of the core dividing surfaces 25a and 25b. In particular, in the bent portion between the magnetic pole portions 91A and 92A and the winding mounting portion 93A and the bent portion between the magnetic pole portions 91B and 92B and the winding mounting portion 93B, the direction and direction of the magnetic flux The longitudinal direction of the magnetic conductive steel sheet 94, that is, the direction of easy magnetization is substantially the same. The grain-oriented electrical steel sheet 94 has excellent magnetic properties in the easy magnetization direction, but is inferior in the perpendicular magnetic properties. According to the commutator motor 3 of the first embodiment, the degree of coincidence between the direction of the magnetic flux of the stator core 9 and the direction of easy magnetization of the directional electromagnetic steel sheet 94 is increased without increasing the number of divisions of the stator core 9. be able to. Therefore, in the stator core 9, only the better magnetic properties of the grain-oriented electrical steel sheet 94 can be mainly utilized, so that the efficiency of the magnetic circuit can be improved. As a result, the efficiency of the commutator motor 3 and the electric blower 1 can be improved.

  Furthermore, in the first embodiment, the core split surfaces 25a and 25b of the stator core 9 are located behind the magnetic pole center line in the rotational direction of the rotor 8 when viewed from the rotational axis direction of the rotor 8. In particular, the following effects can be obtained by being in the vicinity of the direction perpendicular to the electrical neutral axis. As shown in FIG. 4, the magnetic flux lines are divided into two circuits, a circuit that circulates on the left side and a circuit that circulates on the right side across a straight line connecting the core split surfaces 25a and 25b in the vicinity of the direction perpendicular to the electrical neutral axis. Divided into For this reason, the magnetic flux does not cross the core dividing surfaces 25a and 25b. Therefore, in this Embodiment 1, since the influence of the efficiency fall by magnetic flux crossing the division | segmentation surface of the stator core 9 is suppressed reliably, the efficiency of a magnetic circuit further improves.

  Since the magnetic flux density is low in the vicinity of the core dividing surfaces 25a and 25b, even if the core dividing surfaces 25a and 25b are slightly deviated from the direction perpendicular to the electrical neutral axis, the influence is small. That is, the same effect as described above can be obtained even if the core split surfaces 25a and 25b are slightly deviated from the direction perpendicular to the electrical neutral axis. Therefore, the above effect can be achieved even if the electrical neutral axis is slightly deviated due to a change in the balance of magnetic flux due to a change in load during operation of the commutator motor 3. Further, for the purpose of improving the rigidity of the stator core 9 or improving the assemblability of the commutator motor 3, the first stator core 9A and the second stator core 9B are welded to the core dividing surfaces 25a and 25b after the field winding 10 is mounted. You may join using methods, such as adhesion | attachment. Even in such a case, since the influence on the magnetic flux is small, the same effect as described above can be obtained.

  As the rotor 8 rotates, the magnetic flux lines rotate relative to the rotor core 12. For this reason, it is preferable to comprise the rotor core 12 with a non-oriented electrical steel plate. That is, the rotor core 12 is preferably configured by laminating and fixing a plurality of non-oriented electrical steel sheets in the direction of the rotation axis of the rotor 8.

  In the first embodiment, the stator core 9 is divided into the first stator core 9A and the second stator core 9B, so that the field windings 10 can be easily aligned. FIG. 5 is a schematic diagram showing a flyer winding machine that is an example of an automatic machine that performs aligned winding of the field winding 10. The flyer winding machine shown in FIG. 5 includes a core fixing jig 27 for fixing the first stator core 9A or the second stator core 9B, and a flyer arm 28 having a nozzle 29 for guiding the wire 34 at the tip. The core fixing jig 27 fixes the first stator core 9A or the second stator core 9B so that the rotation axis of the flyer arm 28 and the central axis of the winding mounting portion 93A or 93B coincide. The wire 34 is fed out from the nozzle 29 through the flyer arm 28. The flyer arm 28 moves in the direction of its rotation axis while rotating. With such a flyer winding machine, the field winding 10 can be formed by winding the wire 34 around the winding mounting portion 93A of the first stator core 9A or the winding mounting portion 93B of the second stator core 9B. it can. The position where the wire 34 is placed is controlled by controlling the rotation of the flyer arm 28 and the movement in the direction of the rotation axis in synchronization. However, since the wire 34 normally uses a copper wire or an aluminum wire having a diameter of 2 mm or less, its rigidity is small. In addition, the bending history remains on the wire 34 due to the deformation history until the nozzle 29 is inserted. For these reasons, the wire 34 coming out from the outlet of the nozzle 29 may not be straight, the position where the wire 34 is placed may be shifted from the target position, and the aligned windings may be disturbed. In order to suppress this phenomenon, the closer the nozzle 29 is to the surface on which the wire 34 is placed, the better. Therefore, it is suitable for the aligned winding that the left and right spaces of the field winding 10 are opened and the nozzle 29 can be brought closer. In the first embodiment, since the stator core 9 is divided into the first stator core 9A and the second stator core 9B, the nozzle 29 can be brought close to the winding mounting portion 93A or 93B. Ten aligned windings can be easily and accurately performed. The situation is the same in the case where a so-called spindle winding method is adopted in which the nozzle 29 is fixed and the first stator core 9A or the second stator core 9B is rotated. Is obtained.

Embodiment 2. FIG.
Next, the second embodiment of the present invention will be described with reference to FIG. 6 to FIG. 8. The description will focus on the differences from the first embodiment described above, and the same or corresponding parts will be denoted by the same reference numerals. The description is omitted.

  FIG. 6 is a cross-sectional view of the main part of the commutator motor 3 according to the second embodiment as viewed from the blower part 2 side in the rotation axis direction of the rotor 8. FIG. 7 shows only the stator core 9 extracted from FIG. As shown in FIGS. 6 and 7, in the second embodiment, in the magnetic pole portions 91 </ b> A, 92 </ b> A, 91 </ b> B, and 92 </ b> B of the stator core 9, The number of layers gradually decreases. Further, in the magnetic pole portions 91 </ b> A, 92 </ b> A, 91 </ b> B, and 92 </ b> B of the stator core 9, the end portions 941 of the plurality of layers of the directional electromagnetic steel sheet 94 face the rotor 8. That is, the end portion 941 of each layer of the laminated grain-oriented electrical steel sheets 94 forms a surface facing the rotor 8, that is, the inner peripheral surface of the stator core 9. The distance between the end portion 941 of the grain-oriented electrical steel sheet 94 and the core dividing surfaces 25a and 25b increases as the layer becomes closer to the magnetic pole portions 91A, 92A, 91B, and 92B. The closer to the core dividing surfaces 25a, 25b, the smaller the magnetic path width of the stator core 9 becomes.

  In the second embodiment, the configuration as described above makes the intervals between the magnetic flux lines more uniform, and the magnetic flux density in each directional electromagnetic steel sheet 94 becomes more uniform. The degree of coincidence with the easy magnetization direction of the grain-oriented electrical steel sheet 94 can be further increased as compared with the first embodiment. In the second embodiment, the core dividing surfaces 25a and 25b are inclined with respect to the magnetic pole center line. However, it is not limited to such a configuration, and the core dividing surfaces 25a and 25b may be positioned at the magnetic pole center line. Even when the core dividing surfaces 25a and 25b are positioned at the magnetic pole center line, the closer the core dividing surfaces 25a and 25b are to the core dividing surfaces 25a and 25b, the more the number of layers of the directional electromagnetic steel sheets 94 is reduced. Similar effects can be obtained. In this Embodiment 2, it is preferable to comprise so that a layer may reduce in order from the inner layer of the laminated grain-oriented electrical steel sheet 94 as it approaches the core division | segmentation surfaces 25a and 25b.

  FIG. 8 is an example of a magnetic flux diagram of the commutator motor 3 according to the second embodiment obtained by electromagnetic field analysis. As shown in FIG. 8, the magnetic flux lines are divided into two circuits, a circuit that circulates on the left side and a circuit that circulates on the right side across a straight line connecting the core dividing surfaces 25a and 25b in the vicinity of the direction perpendicular to the electrical neutral axis. Divided into Magnetic flux lines from the rotor core 12 to the stator core 9 near the core dividing surface 25a cross from the stator core 9 to the rotor core 12 near the core dividing surface 25b. The magnetic flux lines extending from the rotor core 12 to the stator core 9 at a location far from the core dividing surface 25a pass from the stator core 9 to the rotor core 12 at a location far from the core dividing surface 25b. Accordingly, the number of magnetic flux lines in the magnetic poles 26a and 26b is small near the core dividing surfaces 25a and 25b, and gradually increases as the distance from the core dividing surfaces 25a and 25b increases. In the second embodiment, the closer to the core dividing surfaces 25a and 25b, the smaller the magnetic path width, so that the intervals between the magnetic flux lines become more uniform and the magnetic flux density becomes more uniform. In the lamination of the directional electromagnetic steel sheets 94, the laminated end portions 941 are used as surfaces facing the rotor 8, that is, the inner peripheral surfaces of the stator core 9, and the directional electromagnetic steel sheets 94 are closer to the core dividing surfaces 25 a and 25 b. By configuring so that the number of stacked layers gradually decreases, the above-described effects can be reliably realized. According to the second embodiment, the efficiency of the magnetic circuit can be further improved as compared with the first embodiment. As a result, the efficiency of the commutator motor 3 and the electric blower 1 can be further improved. Further, according to the second embodiment, the amount of the directional electromagnetic steel sheet 94 used can be reduced compared to the first embodiment, and the commutator motor 3 and the electric blower 1 can be reduced in weight.

Embodiment 3 FIG.
Next, the third embodiment of the present invention will be described with reference to FIGS. 9 and 10. The third embodiment will be described mainly with respect to the differences from the above-described embodiments, and the same or corresponding parts will be denoted by the same reference numerals. The description is omitted.

  FIG. 9 is a schematic diagram illustrating an example of a cutting process of the commutator motor manufacturing method according to the third embodiment of the present invention. FIG. 10 is a schematic diagram illustrating an example of a bending process of the commutator motor manufacturing method according to the third embodiment of the present invention.

  The commutator motor manufacturing method of the third embodiment is a method of manufacturing the commutator motor 3 of the present invention. The commutator motor manufacturing method according to the third embodiment is characterized by the process of manufacturing the stator core 9. The process of manufacturing the stator core 9 includes a cutting process, a bending process, and a lamination fixing process of the grain-oriented electrical steel sheet 94.

  In the cutting step, the grain-oriented electrical steel sheet 94 is cut into a rectangular strip having a predetermined length L and width W. The longitudinal direction of the grain-oriented electrical steel sheet 94, that is, the direction of the length L is the easy magnetization direction. The length L of the directional electromagnetic steel sheets 94 of each layer stacked in the first stator core 9A or the second stator core 9B corresponds to the magnetic path length of each layer and is different. On the other hand, the width W of the directional electromagnetic steel sheet 94, that is, the length in the short side direction, corresponds to the length of the stator core 9 in the direction of the rotation axis of the rotor 8. For this reason, the width W of the directional electrical steel sheet 94 of each layer is equal. Therefore, when manufacturing the stator core 9, as shown in FIG. 9, it is preferable to prepare a coil material 101 obtained by winding a strip-shaped directional electromagnetic steel sheet 94 that has been slit in advance so as to have a width W. The apparatus 100 used in the cutting process includes an uncoiler 102 that feeds the directional electromagnetic steel plate 94 from the coil material 101, a roll feeder 103 that feeds the directional electromagnetic steel plate 94 fed from the uncoiler 102 with a pair of rollers, and a roll feeder 103. And a discharge mechanism 105 for discharging the directional electromagnetic steel sheet 94 cut by the blade 104. The cutting method may be any method such as shearing or pressing.

  The length L of the grain-oriented electrical steel sheet 94 varies depending on the position in the stacking direction of the first stator core 9A or the second stator core 9B. For this reason, in the cutting process, it is necessary to change the length L of the grain-oriented electrical steel sheet 94 for each sheet. In order to cope with this, the apparatus 100 has a servo mechanism that controls the relative position of the blade 104 with respect to the longitudinal direction of the grain-oriented electrical steel sheet 94. That is, the apparatus 100 has a servo mechanism that controls the feed amount of the directional electromagnetic steel sheet 94 according to the roll rotation angle of the roll feeder 103 and the timing to lower the blade 104. By controlling the relative position of the blade 104 with respect to the longitudinal direction of the directional electromagnetic steel sheet 94, the length L of the directional electromagnetic steel sheet 94 can be controlled. According to the cutting process using such an apparatus 100, the grain-oriented electrical steel sheets 94 having different lengths L for each sheet can be manufactured with high productivity.

  The configuration of the servo mechanism that controls the relative position of the blade 104 with respect to the longitudinal direction of the grain-oriented electrical steel sheet 94 is not limited to the configuration of the third embodiment. Instead of the configuration of the third embodiment, the cutter 104 may be moved in the longitudinal direction of the directional electromagnetic steel plate 94.

  The bending process is a process of bending the grain-oriented electrical steel sheet 94 cut in the cutting process at a predetermined bending position and bending radius. As a bending method, roll bending is suitable. In the bending process, as shown in FIG. 10, roll bending is performed by an apparatus 110 that includes a roll feeder 112 that feeds a directional electromagnetic steel sheet 94 between a pair of rollers and a plurality of bending rollers 113. The bending position and bending radius of the grain-oriented electrical steel sheet 94 vary depending on the position in the stacking direction of the first stator core 9A or the second stator core 9B. For this reason, in a bending process, it is necessary to change the bending position and bending radius of the grain-oriented electrical steel sheet 94 for each sheet. In order to cope with this, the apparatus 110 has a servo mechanism that controls the relative position of the bending roller 113 with respect to the grain-oriented electrical steel sheet 94. That is, the apparatus 110 sends the feed amount of the directional electromagnetic steel sheet 94 according to the roll rotation angle of the roll feeder 112 and the movement amount by which the bending roller 113 is moved in the vertical direction in FIG. It has a servo mechanism to control. By controlling the feed amount of the directional electromagnetic steel sheet 94 by the roll feeder 112 and the relative position of the bending roller 113 with respect to the roll feeder 112, the bending position and the bending radius of the directional electromagnetic steel sheet 94 can be controlled. According to the bending process using such an apparatus 110, the grain-oriented electrical steel sheet 94 having different bending positions and bending radii can be manufactured with high productivity for each sheet.

  The configuration of the servo mechanism that controls the relative position of the bending roller 113 with respect to the grain-oriented electrical steel sheet 94 is not limited to the configuration of the third embodiment. Instead of the configuration of the third embodiment, the roll of the roll feeder 112 may be moved in the vertical direction in FIG. Further, as a bending method other than roll bending, for example, there is a press die bending using a die and a punch, but in order to change the bending position and the bending radius, it is necessary to prepare a plurality of types of dies, which is expensive. Therefore, it is not suitable.

  In the lamination fixing step, the plurality of grain-oriented electrical steel sheets 94 formed through the cutting step and the bending step are fixed in a stacked state. As a fixing method, there are methods such as welding and adhesion. By the above method, the stator core 9 can be manufactured at low cost and at high speed. In the commutator motor manufacturing method according to the third embodiment, a known method can be applied except for the process of manufacturing the stator core 9.

Embodiment 4 FIG.
Next, the fourth embodiment of the present invention will be described with reference to FIG. 11. The description will focus on the differences from the above-described embodiment, and the same or corresponding parts will be described with the same reference numerals. Omitted.

  FIG. 11: is sectional drawing which shows the vacuum cleaner of Embodiment 4 of this invention. As shown in FIG. 11, the electric vacuum cleaner 40 according to the fourth embodiment includes a cleaner main body 41 on which the electric blower 1 of the present invention is mounted, an inlet 42 for sucking outside air into the cleaner main body 41, and The vacuum cleaner main body 41 has a dust collecting unit 43 that collects dust in the air sucked into the cleaner body 41 and a discharge port 44 that discharges the air sucked into the cleaner main body 41 to the outside of the cleaner main body 41. The electric blower 1 generates an air flow that sucks outside air from the suction port 42 and discharges it from the discharge port 44. The air sucked from the suction port 42 is discharged to the outside of the cleaner body 41 through the dust collection unit 43, the electric blower 1, and the discharge port 44.

  As described above, the efficiency of the electric vacuum cleaner 40 can be improved by incorporating the electric blower 1 into the electric vacuum cleaner 40. In addition, although the case where the electric blower 1 was mounted in the vacuum cleaner 40 was demonstrated as an example, the product incorporating the electric blower 1 of this invention is not limited to the vacuum cleaner 40, For example, a hand dryer etc. It can also be incorporated into other products. Moreover, the use of the commutator motor 3 of the present invention is not limited to the electric blower 1 and the electric vacuum cleaner 40, and can be applied to, for example, an electric tool, a mixer, a coffee mill, and the like.

DESCRIPTION OF SYMBOLS 1 Electric blower, 2 Blower part, 3 Commutator motor, 4 Fan, 5 Fan guide, 6 Frame, 7 Stator, 8 Rotor, 9 Stator core, 9A 1st stator core, 9B 2nd stator core, 10 Field winding, 11 shaft, 12 rotor core, 13 commutator, 14, 15 bearing, 16 end, 17 armature winding, 18 segment, 19 brush, 20 air gap, 21 bracket, 22, 24 insulation member, 23 wedge, 25a, 25b core Dividing surface, 26a, 26b Magnetic pole, 27 Core fixing jig, 28 Flyer arm, 29 Nozzle, 30, 31, 32, 33 area, 34 Wire, 40 Vacuum cleaner, 41 Vacuum cleaner body, 42 Suction port, 43 Dust collection Part, 44 discharge port, 91A, 92A, 91B, 92B magnetic pole part, 93A, 93B winding Wire mounting part, 94 grain-oriented electrical steel sheet, 100, 110 device, 101 coil material, 102 uncoiler, 103, 112 roll feeder, 104 blade, 105 discharging mechanism, 113 bending roller, 941 end

Claims (8)

A stator having a stator core and field windings;
A rotor having armature windings and disposed inside the stator;
With
The stator core is formed by laminating band-shaped grain-oriented electrical steel sheets whose longitudinal direction is the easy magnetization direction,
The normal of the surface of the grain-oriented electrical steel sheet is perpendicular to the rotation axis of the rotor,
The stator core is divided into a first stator core and a second stator core with a core dividing surface as a boundary,
The commutator motor in which the number of layers of the grain-oriented electrical steel sheets to be stacked decreases as the distance from the core dividing surface decreases. The stator core has a magnetic pole portion that forms a magnetic pole, and a winding mounting portion that is farther from the rotation axis of the rotor than the magnetic pole portion,
The commutator motor according to claim 1, wherein the field winding is mounted on the winding mounting portion.   3. The commutator motor according to claim 1, wherein the core dividing surface is located behind the magnetic pole center line of the stator in the rotation direction of the rotor when viewed from the rotation axis direction of the rotor.   The commutator motor according to any one of claims 1 to 3, wherein the core dividing surface is in the vicinity of a direction perpendicular to an electrical neutral axis during rated operation of the commutator motor.   5. The commutator motor according to claim 1, wherein, in the magnetic pole portion of the stator core, end portions of the plurality of layers of the grain-oriented electrical steel sheet respectively face the rotor. The commutator motor according to any one of claims 1 to 5,
A fan driven by the commutator motor;
An electric blower.   A vacuum cleaner comprising the electric blower according to claim 6. A commutator motor manufacturing method comprising a step of manufacturing a stator core of a commutator motor according to any one of claims 1 to 5,
A cutting step of cutting the short side of the band-shaped grain-oriented electrical steel sheet whose longitudinal direction is the easy magnetization direction;
Bending process for bending the grain-oriented electrical steel sheet cut in the cutting process;
A lamination fixing step of fixing the grain-oriented electrical steel sheet bent in the bending step as a laminated state;
With
In the cutting step, the length of the directional electromagnetic steel sheet is controlled by a device having a blade and a servo mechanism that controls the relative position of the cutter with respect to the longitudinal direction of the directional electromagnetic steel sheet,
In the bending process, a bending position and a bending radius of the directional electromagnetic steel sheet are controlled by a device having a plurality of bending rollers and a servo mechanism that controls a relative position of the bending roller with respect to the directional electromagnetic steel sheet. ,
A commutator motor manufacturing method for manufacturing the stator core through the cutting step, the bending step, and the lamination fixing step.

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