JPWO2022202274A5 - - Google Patents

Description

The present disclosure relates to electric motors and electric blowers.

Electric motors are widely used in the field of electrical equipment installed in vehicles such as automobiles. For example, electric motors are used in two-wheel or four-wheel vehicles to drive cooling fans that cool radiators and batteries.

As electric motors, brushed electric motors that use brushes and brushless electric motors that do not use brushes are known. Among these, a brushed electric motor consists of a stator, a rotor that rotates due to the magnetic force of the stator, a commutator attached to the rotor's rotating shaft, a brush that makes sliding contact with the commutator, and a brush that pushes the brush against the commutator. and a spring for application (see, for example, Patent Document 1). In such electric motors, depending on the operating time, the brushes wear and their length decreases. In the electric motor described in Patent Document 1, by using a constant force spring as a spring for pressing the brush against the commutator, as the length of the brush decreases, the constant force spring pushes the brush against the commutator. I'm trying to suppress fluctuations in the applied force.

Japanese Patent Application Publication No. 2014-147171

The constant force spring described in Patent Document 1 is made of a band-shaped wire rod. This strip-shaped wire is made of a non-magnetic material so as not to be affected by the magnetic flux generated by the armature winding. However, for example, even if the constant force spring is made of austenitic stainless steel, which is one of the non-magnetic materials, it becomes magnetic due to processing stress during winding of the band-shaped wire. In particular, since the constant force spring has a band-like shape, its surface area is large. Therefore, when a constant force spring is magnetic, the force exerted by the magnetic flux cannot be ignored. Therefore, the constant force spring is drawn toward the armature winding by the magnetic flux generated by the armature winding. As a result, the direction in which the constant force spring pushes the brush may vary, or the load may vary.

The present disclosure has been made in order to solve such problems, and it is an object of the present disclosure to provide an electric motor that can suppress the influence of magnetic flux generated by an armature winding on a constant load spring, and an electric blower equipped with the electric motor. purpose.

In order to achieve the above object, one aspect of the electric motor according to the present disclosure includes a rotor having a rotating shaft, a commutator attached to the rotor, a brush in contact with the commutator, and a brush connected to the commutator. a plurality of armature windings arranged between the plurality of armature windings, a constant force spring configured of a band-shaped wire material and pressing the brush against the commutator, and arranged between the plurality of armature windings and the constant force spring, and a soft magnetic member that shields magnetic flux generated by the plurality of armature windings.

In order to achieve the above object, one aspect of the electric blower according to the present disclosure includes the above electric motor and a fan attached to the rotating shaft.

According to the present disclosure, it is possible to realize an electric motor that can suppress the influence of magnetic flux generated by an armature winding on a constant load spring, and an electric blower equipped with the electric motor.

FIG. 1 is an external perspective view of the electric motor according to the embodiment when viewed from below. FIG. 2 is an external perspective view of the electric motor according to the embodiment when viewed from above. FIG. 3 is a sectional view of the electric motor according to the embodiment. FIG. 4 is a perspective view showing the internal structure of the brush holder in the electric motor according to the embodiment. FIG. 5 is a perspective view showing the configuration of the constant force spring according to the embodiment. FIG. 6 is an enlarged sectional view of a part of the electric motor according to the embodiment. FIG. 7 is a plan view showing a modification of the arrangement of the constant force spring 110 and the brush 40. FIG. 8 is a perspective view showing a fan attached to the electric motor according to the embodiment. FIG. 9 is a schematic diagram of an electric blower including a fan attached to an electric motor.

Embodiments of the present disclosure will be described below with reference to the drawings. Note that the embodiments described below each represent a specific example of the present disclosure. Therefore, the numerical values, shapes, materials, components, arrangement positions and connection forms of the components, etc. shown in the following embodiments are merely examples and do not limit the present disclosure. Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims representing the most important concept of the present disclosure will be described as arbitrary constituent elements.

Note that each figure is a schematic diagram and is not necessarily strictly illustrated. Further, in each figure, substantially the same configurations are denoted by the same reference numerals, and overlapping explanations will be omitted or simplified. Furthermore, in this specification, the terms "upper" and "lower" do not necessarily refer to the upper direction (vertically upward) and the downward direction (vertically downward) in absolute spatial recognition.

(Embodiment)
[1. overall structure]
First, the overall configuration of the electric motor 1 according to the embodiment will be described using FIGS. 1 to 4. FIG. 1 is an external perspective view of an electric motor 1 according to the present embodiment, viewed from below. FIG. 2 is an external perspective view of the electric motor 1 viewed from above. FIG. 3 is a sectional view of the electric motor 1. Specifically, FIG. 3 is a III-III cross-sectional view of the electric motor 1 shown in FIG. be. FIG. 4 is a perspective view showing the internal structure of the brush holder 50 in the electric motor 1. As shown in FIG. Note that in FIG. 3, only the portion that appears in the cross section of the electric motor 1 is illustrated. Further, FIG. 4 shows a perspective view of the brush holder 50 from below with the cover plate 131 removed.

As shown in FIG. 3, the electric motor 1 includes a stator 10 (stator) and a rotor 20 (rotor) that rotates due to the magnetic force of the stator 10. The electric motor 1 according to the present embodiment is a brushed electric motor, and further includes a commutator 30 attached to a rotating shaft 21 provided on a rotor 20, as shown in FIG. Two brushes 40 are provided in contact with the brush 30.

As shown in FIGS. 3 and 4, the electric motor 1 further includes a brush holder 50 that holds the brush 40, and a constant force spring 110 that presses the brush 40 against the commutator 30. The electric motor 1 also includes a bearing 91, a first bracket 101, and a second bracket 102.

The electric motor 1 according to the present embodiment is a type of DC motor driven by direct current, and includes a magnet 11 as a stator 10 and an armature winding 22 as a rotor 20. child is used. Further, in this embodiment, the electric motor 1 is a flat brushed coreless motor (flat motor) mounted on a two-wheeled or four-wheeled vehicle. Therefore, the stator 10 and the rotor 20 do not have a core (iron core), and the electric motor 1 as a whole is thin and light. In this embodiment, the thickness of the electric motor 1 (that is, the dimension in the direction of the axis C of the rotating shaft 21) is smaller than the outer diameter (the dimension in the direction perpendicular to the direction of the axis C). Specifically, the electric motor 1 according to the present embodiment is a small motor used for a cooling fan of a radiator in a vehicle, and the outer diameter (diameter) of the electric motor 1 is 120 mm or less. As an example, the outer diameter of the electric motor 1 is 62 mm. Note that the electric motor 1 is driven by an input voltage of 12V DC.

Each component of the electric motor 1 will be explained in detail below.

As shown in FIG. 3, the stator 10 is arranged with a small air gap 12 interposed between the stator 10 and the rotor 20. As shown in FIG. Stator 10 generates magnetic force that acts on rotor 20. The stator 10 is configured to generate magnetic flux on an air gap surface 12a with the rotor 20, and forms a magnetic circuit together with the rotor 20, which is an armature. Specifically, the stator 10 has a substantially donut shape as a whole, and N poles and S poles are alternately and evenly present on the air gap surface 12a with the rotor 20 along the circumferential direction of the rotating shaft 21. It is configured as follows. The stator 10 is a field that generates magnetic flux for generating torque, and in this embodiment, is composed of a plurality of magnets 11 (magnets). The magnet 11 is, for example, a permanent magnet having an S pole and an N pole.

The plurality of magnets 11 constituting the stator 10 are arranged so that N poles and S poles are alternately and evenly distributed over the circumferential direction. In this embodiment, the direction of the main magnetic flux generated by the stator 10 (magnet 11) is along the direction in which the rotating shaft 21 extends. The direction of the main magnetic flux is generated in a direction according to the magnetic poles of the magnet 11. Stator 10 is fixed to first bracket 101.

As shown in FIG. 3, the rotor 20 has a rotating shaft 21 and rotates around an axis C of the rotating shaft 21. As shown in FIG. The rotor 20 generates magnetic force that acts on the stator 10. In this embodiment, the direction of the main magnetic flux generated by rotor 20 is along the direction in which rotating shaft 21 extends. The direction of the main magnetic flux is generated in a direction according to the direction of the current flowing through the armature winding 22.

The rotor 20 is arranged facing the stator 10. In this embodiment, the rotor 20 faces the stator 10 in the direction of the axis C of the rotating shaft 21.

The rotating shaft 21 is a shaft having an axis C, and is a long rod-like member such as a metal rod. The axis C of the rotating shaft 21 is the center around which the rotor 20 rotates. The longitudinal direction of the rotating shaft 21, that is, the direction in which the rotating shaft 21 extends (stretching direction) is also referred to as the direction of the axial center C (axial center direction).

The rotating shaft 21 is supported by a bearing 91. As an example, the bearing 91 is a bearing such as a ball bearing.

In this embodiment, the first end 21 a of the rotating shaft 21 is an output side end (output shaft) and protrudes from the first bracket 101 and the bearing 91 . A load such as a fan is attached to the first end 21a. Note that the second end 21 b of the rotating shaft 21 is an end on the opposite output side (anti-output shaft) and protrudes from the second bracket 102 .

The bearing 91 is held by the first bracket 101. Specifically, the bearing 91 is fixed to a recess provided in the first bracket 101.

The first bracket 101 is a member that constitutes a housing together with the second bracket 102. A stator 10 and a rotor 20 are arranged in a casing made up of a first bracket 101 and a second bracket 102. In the present embodiment, the first bracket 101 is an outer member of the electric motor 1, and is formed into a bottomed cylindrical shape having a bottom portion and a cylindrical side wall portion. A magnet 11 constituting the stator 10 is fixed to the bottom of the first bracket 101. Further, the armature winding 22 of the rotor 20 is surrounded by the side wall portion of the first bracket 101. The first bracket 101 is made of, for example, a metal material. For example, the first bracket 101 is made of iron-based material such as cold rolled steel plate (SPC material) or metal such as aluminum. Note that the material of the first bracket 101 is not limited to a metal material, and may be a resin material, but from the viewpoint of suppressing noise generated from the electric motor 1, the first bracket 101 is made of a metal material. It would be good if it was done.

The second bracket 102 is a member that constitutes a housing together with the first bracket 101. The second bracket 102 is made of a plate-shaped soft magnetic material. The second bracket 102 is an example of a soft magnetic member that is disposed between the plurality of armature windings 22 and the constant load spring 110 and shields the magnetic flux generated by the plurality of armature windings 22. In this embodiment, the second bracket 102 is made of an iron plate. Note that the soft magnetic material forming the second bracket 102 is not limited to iron. As the soft magnetic material, for example, permalloy, silicon iron, etc. can be used.

As shown in FIG. 3, the rotor 20 includes a rotating shaft 21, a plurality of armature windings 22, and a molded resin 23 that covers the plurality of armature windings 22.

Each of the plurality of armature windings 22 is made of an electric wire, and is wound so as to generate a magnetic force acting on the stator 10 when a current flows therethrough. In this embodiment, the direction of the main magnetic flux generated by each armature winding 22 is in the direction of the axis C of the rotating shaft 21. That is, the magnets 11 of the stator 10 and the armature windings 22 of the rotor 20 are aligned in the direction of the axis C of the rotating shaft 21.

Each armature winding 22 is constituted by an insulated wire having a core wire made of a metal such as copper or aluminum and an insulating film covering the core wire. In this embodiment, each of the plurality of armature windings 22 is a thin wire-wound coil having a coil layer in which a conductive wire is wound in a planar shape. Specifically, each of the plurality of armature windings 22 is constituted by, for example, one or more coil layers in which insulated wires are wound in a substantially fan shape in plan view. The plurality of armature windings 22 configured in this manner are arranged so as to surround the rotating shaft 21 when viewed from the direction of the axis C of the rotating shaft 21.

Each of the plurality of armature windings 22 is connected to a commutator 30. Specifically, each of the plurality of armature windings 22 is electrically connected to one of the plurality of commutator pieces 31 of the commutator 30.

The plurality of armature windings 22 are integrally molded together with the mold resin 23 by being covered with the mold resin 23. The mold resin 23 is made of an insulating resin material such as phenol resin or unsaturated polyester (BMC).

As shown in FIG. 3, the commutator 30 is attached to the rotating shaft 21. Therefore, the commutator 30 rotates together with the rotating shaft 21 as the rotor 20 rotates. The commutator 30 attached to the rotating shaft 21 may be a part of the rotor 20.

The commutator 30 has a plurality of commutator pieces 31 (commutator segments) provided along the rotational direction of the rotating shaft 21. Specifically, the plurality of commutator pieces 31 are arranged in an annular shape along the rotation direction of the rotation shaft 21 so as to surround the rotation shaft 21 . Note that each commutator piece 31 is a long member extending in the longitudinal direction of the rotating shaft 21.

Each of the plurality of commutator pieces 31 is a conductive terminal made of a metal material such as copper, and is electrically connected to the armature winding 22 of the rotor 20. The plurality of commutator pieces 31 are arranged to be insulated and separated from each other, but are electrically connected by the armature winding 22 of the rotor 20. For example, two adjacent commutator pieces 31 are electrically connected by the armature winding 22.

As an example, the commutator 30 is a molded commutator, and has a configuration in which a plurality of commutator pieces 31 are molded with a molded resin 32. In this case, the plurality of commutator pieces 31 are embedded in the mold resin 32 so that the surfaces thereof are exposed. The molded resin 32 is a commutator body, and is a substantially cylindrical member having a through hole into which the rotating shaft 21 is inserted. The mold resin 32 is, for example, a resin molded body made of an insulating resin material such as a thermosetting resin.

As shown in FIG. 3, two brushes 40 are in contact with the commutator 30. Specifically, each of the two brushes 40 is in contact with the commutator piece 31 of the commutator 30. Since the commutator 30 is rotated by the rotation of the rotating shaft 21, the brush 40 continues to contact all the commutator pieces 31 one after another. Note that the number of brushes 40 is not limited to two, and may be four, for example.

As shown in FIG. 4, two brushes 40 are placed in a brush holder 50. Specifically, each of the two brushes 40 is arranged in the brush holder 50 so that its longitudinal direction is perpendicular to the axis C of the rotating shaft 21 (that is, the radial direction of rotation of the rotating shaft 21). There is.

In this embodiment, the angle formed by the longitudinal directions of the two brushes 40 is 180°. Note that the angle between the two brushes 40 in the longitudinal direction may be less than 180°.

Each of the brushes 40 is a power supply brush (current-carrying brush) that supplies power to the armature winding 22 by contacting the commutator piece 31 . The brush 40 includes a first end 41 in contact with the commutator 30 and a second end 42 located on the opposite side of the first end 41. The brush 40 is a conductor having electrical conductivity. As an example, the brush 40 is an elongated, substantially rectangular carbon brush made of carbon. In this embodiment, the brush 40 is preferably a carbon brush containing metal such as copper. Thereby, the contact resistance between the brush 40 and the commutator piece 31 can be reduced. Such a brush 40 can be produced, for example, by pulverizing a mixture of graphite powder, copper powder , binder resin, and hardening agent, compression molding it into a rectangular parallelepiped, and firing it.

As shown in FIGS. 3 and 4, the same number of constant force springs 110 as the number of brushes 40 are arranged in the brush holder 50. In this embodiment, two constant force springs 110 are arranged. The brush 40 is attached so as to be constantly in contact with the commutator piece 31 of the commutator 30 under a pressing force from the constant force spring 110. That is, the brush 40 is pressed against the commutator 30 by the constant force spring 110.

As shown in FIG. 3, the constant force spring 110 applies pressure (spring pressure) to the brush 40 using spring elastic force (spring restoring force), thereby urging the brush 40 toward the commutator 30. The configuration of the constant force spring 110 will be explained using FIG. 5 as well. FIG. 5 is a perspective view showing the configuration of constant force spring 110 according to this embodiment. As shown in FIG. 5, in this embodiment, the constant force spring 110 is made of a band-shaped wire rod and is a spring that presses the brush 40 against the commutator 30. In other words, the constant force spring 110 is made of a long thin plate. The constant force spring 110 is located at one end of a spiral part 111 around which a band-shaped wire is wound, a fixed part 112 located at the other end, and between the spiral part 111 and the fixed part 112. , and a flat portion 113 in which a band-shaped wire rod has a flat shape. As shown in FIG. 4, the spiral portion 111 contacts the second end 42 of the brush 40. As shown in FIG. The fixing part 112 is fixed to the hook-shaped part 60 of the brush holder 50. In this embodiment, the fixing part 112 is fixed to the brush holder 50 by hooking the opening 117 (see FIG. 5) formed in the fixing part 112 onto the hook-shaped part 60.

The hook-shaped portion 60 on which the fixed portion 112 of the constant force spring 110 is hooked is arranged near the first end portion 41 of the brush 40 . As a result, the spiral portion 111 of the constant force spring 110 pushes the second end 42 of the brush 40 in a direction closer to the first end 41 of the brush 40 where the fixing portion 112 is arranged. Therefore, the first end 41 of the brush 40 is always in contact with the commutator piece 31 due to the pressing force of the constant force spring 110. In this way, since the brush 40 continues to be in contact with the commutator piece 31, it wears out due to friction as the commutator piece 31 rotates. Therefore, due to the pressing force from the constant force spring 110, it moves in the direction (radial direction) toward the axis C of the rotating shaft 21. For example, a metal material can be used as the material constituting the constant force spring 110. In this embodiment, constant force spring 110 is made of austenitic stainless steel, which is a non-magnetic material.

Electric power is supplied to the brush 40 from an external power source located outside the electric motor 1. The external power source is a power source that exists outside the electric motor 1 and supplies a predetermined input voltage to the electric motor 1. In this embodiment, the external power supply is a DC power supply that supplies the motor 1 with an input voltage of 12V DC. Note that the DC power source is not particularly limited as long as it is a power source that outputs DC power, and includes, for example, a generator, a converter, and a battery.

In the electric motor 1 configured as described above, the current supplied to each of the two brushes 40 flows as an armature current (drive current) to the armature winding 22 via the commutator pieces 31 of the commutator 30. As a result, magnetic flux is generated in the rotor 20 (armature winding 22). The magnetic force generated by the interaction between the magnetic flux generated in the rotor 20 and the magnetic flux generated from the stator 10 becomes a torque that rotates the rotor 20. At this time, the direction in which the current flows is switched depending on the positional relationship between the commutator piece 31 of the commutator 30 and each of the two brushes 40. In this way, by switching the direction in which the current flows, a rotational force in a certain direction is generated by the repulsion and attraction of the magnetic force generated between the stator 10 and the rotor 20, and the rotor 20 rotates. Rotates around axis 21.

The brush holder 50 is a holding member that holds the two brushes 40. The brush holder 50 is made of, for example, an insulating resin material. In this embodiment, the brush holder 50 is a resin molded product formed by integral molding using a resin material. As shown in FIG. 3, in this embodiment, the brush holder 50 is an outer shell member that forms the outer shell of the electric motor 1, and covers the second bracket 102 from the outside.

The brush holder 50 includes a holder main body 50a and a hook-shaped portion 60. The holder main body 50a is a portion of the brush holder 50 where the brush is arranged. In other words, the holder main body 50a is a portion of the brush holder 50 other than the hook-shaped portion 60. As shown in FIG. 4, the holder main body 50a of the brush holder 50 has two brush storage parts 51. A brush 40 is stored in each of the two brush storage sections 51. The brush storage portion 51 is formed in a concave shape on the inner surface of the brush holder 50. In this embodiment, the brush storage section 51 has a concave shape, but it may have a box-like shape in which the brush storage section 51 and the cover plate 131 are integrated. The hook-shaped portion 60 is a portion that protrudes from the holder main body 50a along the rotating shaft 21, and is used to fix the constant force spring 110.

In the present embodiment, the brush storage portion 51 is elongated in a direction perpendicular to the axis C of the rotating shaft 21 (that is, in the radial direction of rotation of the rotating shaft 21), and has a concave cross-sectional shape. .

As shown in FIG. 4, each of the two brush storage sections 51, each containing a brush 40, is covered by a cover plate 131. The two cover plates 131 are made of, for example, brass plates, and are arranged so as to cover the brush storage section 51, respectively.

Note that, as shown in FIG. 4, a constant force spring 110 is housed in the brush housing section 51 together with the brush 40.

[2. effect]
Next, the effects of the electric motor 1 according to this embodiment will be explained using FIG. 6. FIG. 6 is an enlarged sectional view of a part of the electric motor 1 according to the present embodiment. In FIG. 6, the constant load spring 110, the armature winding 22, and their surroundings are shown in an enlarged manner in the cross section of the electric motor 1.

Armature winding 22 produces magnetic flux in the direction as shown by the block arrows in FIG. Further, as described above, the constant force spring 110 is made of austenitic stainless steel, which is a non-magnetic material. However, when forming the spiral portion 111 of the constant force spring 110 from a band-shaped wire made of austenitic stainless steel, the constant force spring 110 becomes magnetic due to processing stress. Therefore, if there is no magnetic flux shielding member interposed between the constant force spring 110 and the armature winding 22, the constant force spring 110 is caused by the magnetic flux generated by the armature winding 22. A force is applied in the direction approaching the line 22 (that is, in the direction shown by the dashed arrow in FIG. 6). That is, the constant force spring 110 is attracted to the armature winding 22. In this case, the direction in which the constant force spring 110 pushes the brush 40 may vary, or the load may vary.

In this embodiment, since the second bracket 102 made of a soft magnetic material is arranged between the constant force spring 110 and the armature winding 22, the magnetic flux generated by the armature winding 22 is 2 bracket 102. Therefore, the magnetic flux generated by the armature winding 22 and reaching the constant force spring 110 can be reduced. Thereby, the influence of the magnetic flux generated by the armature winding 22 on the constant force spring can be suppressed. That is, it is possible to suppress fluctuations in the direction in which the constant force spring 110 pushes the brush 40 and fluctuations in the load.

Further, in this embodiment, as shown in FIG. 6, the fixed portion 112 and the flat portion 113 of the constant force spring 110 are located on the opposite side of the brush 40 from the side where the plurality of armature windings 22 are arranged. , placed. In other words, in FIG. 6, the plurality of armature windings 22 are arranged below the brush 40, whereas the fixed part 112 and the flat part 113 of the constant force spring 110 are arranged above the brush 40. be done. The closer the flat portion 113 of the constant force spring 110 is to the plurality of armature windings 22, the greater the force that the flat portion 113 receives from the magnetic flux generated by the plurality of armature windings 22. Therefore, compared to the case where the flat part 113 of the constant force spring 110 is arranged between the brush 40 and the plurality of armature windings 22 (that is, below the brush 40 in FIG. 6), By arranging it on the opposite side to the side where the plurality of armature windings 22 are arranged, the force that the plane portion 113 receives from the magnetic flux generated by the plurality of armature windings 22 can be reduced. Therefore, the influence of the magnetic flux generated by the armature winding 22 on the constant force spring 110 can be further suppressed.

(Modified example)
The electric motor according to the present disclosure has been described above based on the embodiments, but the present disclosure is not limited to the above embodiments.

For example, in the electric motor 1 according to the embodiment described above, the second bracket 102 is a soft magnetic member, but other members disposed between the constant force spring 110 and the plurality of armature windings 22 are soft magnetic members. It may also be a magnetic member. For example, the cover plate 131 may be a soft magnetic member.

Further, although the flat portion 113 of the constant force spring 110 is arranged on the opposite side of the brush 40 to the side where the plurality of armature windings 22 are arranged, the arrangement of the flat portion 113 is not limited to this. For example, the plane portion 113 may be arranged in a circumferential direction with respect to the brush 40, with the axis C direction of the rotating shaft 21 as the center, as shown in FIG. Note that the arrows in FIG. 7 indicate the circumferential direction centered on the axis C direction of the rotating shaft 21. Note that FIG. 7 is a plan view showing a modification of the arrangement of the constant force spring 110 and the brush 40. Such an arrangement can also prevent the flat portion 113 of the constant force spring 110 from being attracted by the magnetic flux generated by the armature winding 22.

Further, in the embodiment described above, the stator 10 is made up of only permanent magnets, but the invention is not limited to this. For example, the stator 10 may be a stator composed of a permanent magnet and an iron core, or may be a stator composed of a stator winding and an iron core without using a permanent magnet.

Further, in the above embodiment, the electric motor 1 is a vehicle motor used in a vehicle, but the present invention is not limited to this. The technology of the present disclosure can also be applied to motors used in various other electrical devices, such as motors used in electric blowers installed in vacuum cleaners and the like.

Here, an example in which the electric motor 1 according to the above embodiment is applied to an electric blower will be described using FIG. 7. FIG. 8 is a perspective view showing a fan 190 attached to the electric motor 1 according to the above embodiment. FIG. 9 is a schematic diagram of an electric blower 600 including a fan 190 attached to the electric motor 1. An electric blower 600 can be realized by attaching a fan 190 as shown in FIG. 8 to the rotating shaft 21 of the electric motor 1 according to the above embodiment. That is, the electric blower according to the present disclosure includes the electric motor 1 of the embodiment described above and the fan 190 attached to the rotating shaft 21 of the electric motor 1. Note that the fan 190 shown in FIG. 8 is an example, and fans having other shapes and structures may be attached to the electric motor 1 according to the above embodiment. Since such an electric blower includes the electric motor 1 according to the embodiment described above, it has the same effects as the electric motor 1 according to the embodiment described above.

Other embodiments may be obtained by making various modifications to the above embodiments that those skilled in the art would think of, or by arbitrarily combining the components and functions of the embodiments and modifications without departing from the spirit of the present disclosure. The present disclosure also includes forms in which:

The technology of the present disclosure can be widely used in various products equipped with electric motors, including products in the field of electrical equipment such as automobiles and the field of household electrical equipment.

1 Electric motor 10 Stator 11 Magnet 12 Air gap 12a Air gap surface 20 Rotor 21 Rotating shaft 21a First end 21b Second end 22 Armature winding 23, 32 Molded resin 30 Commutator 31 Commutator piece 40 Brush 41 First end portion 42 Second end portion 50 Brush holder 50a Holder body 51 Brush storage portion 60 Hook-shaped portion 91 Bearing 101 First bracket 102 Second bracket 110 Constant force spring 111 Spiral portion 112 Fixed portion 113 Plane portion 117 Opening 131 Cover Plate 190 Fan 600 Electric blower

Claims (6)

a rotor having a rotating shaft;
a commutator attached to the rotor;
a brush in contact with the commutator;
a plurality of armature windings connected to the commutator;
a constant force spring configured of a band-shaped plate material and pressing the brush against the commutator;
a soft magnetic member disposed between the plurality of armature windings and the constant load spring and shielding magnetic flux generated by the plurality of armature windings;
Electric motor. The constant force spring is located at one end of a spiral part around which the strip-shaped plate material is wound, a fixed part located at the other end, and between the spiral part and the fixed part, the strip-shaped plate material has a planar portion having a planar shape;
The flat portion is arranged at a position opposite to the plurality of armature windings when viewed from the brush, or in a circumferential direction centered on the axial direction of the rotating shaft with respect to the brush.
The electric motor according to claim 1. The soft magnetic member is composed of an iron plate.
The electric motor according to claim 1 or 2. further comprising a molded resin covering the plurality of armature windings;
The electric motor according to any one of claims 1 to 3. The thickness of the electric motor is smaller than the outer diameter of the electric motor.
The electric motor according to any one of claims 1 to 4. The electric motor according to any one of claims 1 to 5,
a fan attached to the rotating shaft;
Electric blower.

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