JP2019186994A - Electric motor, electric blower provided with electric motor, and electric vacuum cleaner provided with electric blower - Google Patents

Abstract

To provide an electric motor in which the movement of a sleeve can be easily regulated and the mounting work of the sleeve is not complicated.SOLUTION: An electric motor includes a shaft rotatably supported, a rotor core having a plurality of magnetic poles and attached to or integrally formed with the outer periphery of the shaft, and a pair of bearings attached to the outer periphery of the shaft and rotatably supporting the shaft, and a first end cap and a second end cap are respectively attached to the positions corresponding to both ends of the rotor core when viewed in the longitudinal direction of the shaft, and a cylindrical sleeve is provided to cover the outer periphery of the rotor core and cover a part of the outer periphery of the first end cap and the second end cap, and the electric motor is provided with a step portion that restricts the sleeve from moving toward the end of the shaft at the second end cap attached to the end side of the shaft.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an electric motor, and relates to an electric blower provided with the electric motor and a vacuum cleaner provided with the electric blower.

  In recent years, the market demand for the reduction in size and weight of vacuum cleaners has increased, and accordingly, the development of reduction in size and weight of electric motors used in vacuum cleaners has also been advanced. Small and lightweight motors must be rotated at high speed as an electric blower in order to obtain the same amount of air as a conventional motor. An electric motor having a sleeve covering the rotor core so as not to scatter is known (for example, see Patent Document 1).

Japanese Patent Laying-Open No. 2014-003894 (5th page, FIG. 2)

  The conventional electric motor described in Patent Document 1 includes end caps that are members for adjusting the balance at both ends of the rotor core, and a sleeve is provided so as to cover the end cap and the rotor core. And it is fixed with the rotor core and adhesive.

However, since the diameter of the inner circumference of the sleeve is larger than the diameter of the outer circumference of the rotor core and the end cap in the conventional electric motor described in Patent Document 1, the movement of the sleeve is not restricted and the outer circumference of the rotor core and the end cap is free. Will pass through.

Therefore, when performing the installation work as it is, it is difficult to stop the sleeve at a specific position, and separately prepare a tool that determines the position of the sleeve, such as a mounting jig, and fix the position with the adhesive after fixing the position with the mounting jig. There is a problem that it is necessary to perform the operation, and the work is complicated and takes time.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an electric motor in which the movement of the sleeve can be easily regulated and the mounting operation of the sleeve is not complicated.

  An electric motor of the present invention that solves the problem supports a shaft that is rotatably supported, a rotor core that is attached to or integrally formed with the outer periphery of the shaft, and has a plurality of magnetic poles, and that rotatably supports the shaft. And a pair of bearings attached to the outer periphery of the shaft, and the first end cap and the second end cap are respectively attached at positions corresponding to both ends of the rotor core when viewed in the longitudinal direction of the shaft. A second end cap that covers the outer periphery of the rotor core and is provided with a cylindrical sleeve so as to cover a part of the outer periphery of the first end cap and the second end cap, and is attached to the end of the shaft Is provided with a step portion for restricting the sleeve from moving toward the end of the shaft.

  According to the present invention, the cylindrical sleeve is provided so as to cover a part of the outer periphery of the first end cap, the rotor core, and the second end cap, and the second end is attached to the end portion side of the shaft. Since the cap is provided with a stepped portion that restricts the sleeve from moving toward the end of the shaft, the stepped portion of the second endcap after the sleeve has passed through the first endcap and the rotor core. Thus, the sleeve does not move any more, and the sleeve can be held at a predetermined mounting position without using a mounting jig and can be easily fixed with an adhesive.

It is an external appearance perspective view of the electric motor which concerns on Embodiment 1 of this invention. It is sectional drawing seen from the side surface direction of the electric motor which concerns on Embodiment 1 of this invention. It is sectional drawing seen from the side surface direction of the rotor assembly of the electric motor which concerns on Embodiment 1 of this invention. It is a principal part enlarged view of the position where the outer diameter of the axis | shaft of the electric motor which concerns on Embodiment 1 of this invention shown in the A section of FIG. 3 changes. It is a principal part enlarged view of the rotor assembly of the electric motor which concerns on Embodiment 1 of this invention shown in the B section of FIG. It is the perspective view seen from the side surface direction which shows the state before attaching a bearing to the rotor assembly of the electric motor which concerns on Embodiment 1 of this invention. It is an exploded view of the electric blower incorporating the electric motor according to Embodiment 1 of the present invention. It is sectional drawing seen from the side surface direction of the electric blower incorporating the electric motor which concerns on Embodiment 1 of this invention. It is a perspective view which shows the external appearance of the electric vacuum cleaner incorporating the electric motor which concerns on Embodiment 1 of this invention. It is the external view which looked at the main-body part of the vacuum cleaner incorporating the electric motor which concerns on Embodiment 1 of this invention from the side surface direction. It is sectional drawing seen from the side surface direction of the main-body part of the vacuum cleaner incorporating the electric motor which concerns on Embodiment 1 of this invention.

Embodiment 1
(Configuration of electric motor)
Hereinafter, the configuration of the electric motor according to the first embodiment of the present invention will be described with reference to FIGS.
Note that in each drawing, the same reference numerals are given to the same portions or corresponding portions, and a part of the description may be omitted.
The present invention is not limited to the following embodiments, and various modifications and changes can be made without departing from the spirit of the present invention.

  1 is an external perspective view of an electric motor according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view of the electric motor according to Embodiment 1 of the present invention as viewed from the side, and FIG. 3 is Embodiment 1 of the present invention. Fig. 4 is a cross-sectional view of the rotor assembly of the electric motor according to the present invention as viewed from the side, and Fig. 4 is an enlarged view of the main part at the position where the outer diameter of the shaft of the electric motor according to Embodiment 1 of the present invention shown in part A of Fig. 3 changes. 5 is an enlarged view of a main part of the rotor assembly of the electric motor according to the first embodiment of the present invention shown in part B of FIG. 3, and FIG. 6 is a view showing a bearing in the rotor assembly of the electric motor according to the first embodiment of the present invention. It is the perspective view seen from the side surface direction which shows the state before attaching.

  As shown in FIGS. 1 and 2, the electric motor 21 according to the first embodiment of the present invention is a brushless motor, and includes a rotor assembly 6, a stator assembly 7, and a frame 5. The frame 5 is a member that forms a part of the outer shell of the electric motor 21, for example, an aluminum alloy formed by press molding, and has a cylindrical body portion that is open at one end side, and a side opposite to the open side. A housing part 17 having a diameter smaller than that of the body part is formed on the body. There is an opening at the front end of the housing portion 17, and a shaft 8 of the rotor assembly 6 described later passes through the opening.

  The rotor assembly 6 includes a shaft 8, a rotor core 9, a first end cap 10a, a second end cap 10b, a sleeve 11, a first bearing 13a, a second bearing 13b, a wave washer 14, a spacer 15, and a cushion. 16.

  The rotor core 9 is a plastic magnet, and is formed by injection molding by kneading a magnetic material powder or finely pulverized material into a molding material such as resin or elastomer. The shaft 8 is made of, for example, stainless steel. As a manufacturing method, the shaft 8 is set in an injection mold, the plastic magnet molding material rotates around the shaft 8 and injection molding is performed, and the rotor core 9 is integrated with the shaft 8. Is done. By forming in this way, the assembly is more stable than the method in which the separately formed rotor core 9 is bonded and fixed to the shaft 8, and the reliability of the electric motor 21 can be improved and the life can be extended.

  The plastic magnet that constitutes the rotor core 9 is less likely to crack or chip than a sintered magnet. However, since it rotates at a high speed, for example, 100,000 revolutions per minute, it prevents scattering when it breaks. In addition, as shown in FIGS. 3 and 5, the first end cap 10 a and the second end cap 10 b are attached to both ends of the rotor core 9 in the longitudinal direction of the shaft 8. The first end cap 10a and the second end cap 10b are formed of a nonmagnetic metal material, such as brass.

When the first end cap 10a and the second end cap 10b are made of a magnetic material, an unnecessary magnetic flux passage path is formed, which may adversely affect the magnetic circuit when the rotor assembly 6 is rotated. Therefore, the first end cap 10a and the second end cap 10b are formed of a nonmagnetic metal material so as not to affect the magnetic circuit.

  As shown in FIG. 3, the first end cap 10a is attached to a position near a pair of bearings 13 described later. The second end cap 10 b is attached to the end side of the shaft 8.

  The inner peripheral diameters of the first end cap 10a and the second end cap 10b are smaller than the outer peripheral diameter of the shaft 8, and are press-fitted and attached. A second end cap 10b is attached to the end of the shaft 8 by press-fitting, and a first end cap 10a is attached to the opposite end by press-fitting.

  An inclined portion 10a1 is provided over the entire circumference at the inner circumferential end of the first end cap 10a. Similarly, an inclined portion 10b1 is provided over the entire circumference at the inner circumferential end of the second end cap 10b.

  The inclined portion 10a1 and the inclined portion 10b1 are, for example, C0.5 chamfered shapes. These inclined portions 10a1 and 10b1 are for relaxing the resistance at the time of press-fitting. By providing the inclined portions 10a1 and 10b1, end portions on the inner circumferences of the first end cap 10a and the second end cap 10b are provided. Compared to the case of a corner, it can be easily inserted into the shaft 8.

In the embodiment of the present invention, the inner end portions of the first end cap 10a and the second end cap 10b are inclined portions. However, for example, an R shape such as R0.5 may be used. Compared to the case where the end is a corner, it can be easily inserted into the shaft 8.

  The first end cap 10a and the second end cap 10b can be held with a high holding force by being press-fitted and attached, and the first end cap 10a and the second end cap 10b are bonded to the shaft 8. Compared to the fixing method, the assembly is stable, the reliability of the electric motor 21 can be improved, and the life can be extended.

  In a state where the first end cap 10a and the second end cap 10b are press-fitted to a predetermined position, the end of the rotor core 9 in the longitudinal direction of the shaft 8 and the longitudinal direction of the first end cap 10a and the shaft 8 As shown in FIG. 5, a minute gap W remains between the other end of the rotor core 9 and between the rotor core 9 and the second end cap 10b. The minute gap W is a gap of about 0.01 mm, for example.

Between the end of the rotor core 9 in the longitudinal direction of the shaft 8 and the first end cap 10a, between the end of the other end of the rotor core 9 in the longitudinal direction of the shaft 8 and the rotor core 9 and the second end cap 10b. The reason why the minute gap W remains is to prevent residual stress from being applied to the rotor core 9 when the first end cap 10a and the second end cap 10b are press-fitted.

  When the first end cap 10a and the second end cap 10b are press-fitted into contact with the rotor core 9, residual stress is applied to the rotor core 9, and as described above, the electric motor 21 that is a brushless motor is as described above. Since the rotor rotates at a high speed of 100,000 rpm, the rotor core 9 may be damaged.

Therefore, a gap is left between the first end cap 10a and the second end cap 10b and the rotor core 9 so that residual stress is not applied to the rotor core 9. In this embodiment, a gap is left. However, if no residual stress is applied, for example, the contact may be made with a gap of 0 mm.

Furthermore, in order to suppress damage to the rotor core 9, a cylindrical sleeve 11 is inserted so as to cover the outer periphery of the rotor core 9. The sleeve 11 is made of non-magnetic, for example, a composite material of carbon fiber and resin. A composite material of carbon fiber and resin is lightweight, high in strength, and excellent in heat resistance.

  The diameter of the outer periphery of the rotor core 9 and the diameter of the outer periphery of the first end cap 10a are the same and are φ3. The inner diameter of the sleeve 11 is φ4, and the dimensional relationship with the outer diameter of the rotor core 9 and the first end cap 10a is φ4> φ3. The inner diameter of the sleeve 11 is the rotor. It is larger than the outer diameter of the core 9 and the first end cap 10a. Therefore, the sleeve 11 is inserted smoothly. The sleeve 11 can be inserted even if the inner diameter of the sleeve 11 is the same as the outer diameter of the rotor core 9 and the first end cap 10a.

  The second end cap 10b is provided with a sleeve receiving portion 10b3 that is a step portion for preventing the sleeve 11 from coming off. The outer diameter φ6 of the small diameter portion 10b3 of the second end cap 10b is the same as the outer diameter of the rotor core 9 and φ3 which is the outer diameter of the first end cap 10a, that is, φ6 = φ3. . The outer diameter φ5 excluding the small diameter portion 10b3 of the second end cap 10b is larger than the inner diameter φ4 of the sleeve 11.

Therefore, the sleeve 11 is inserted up to the small diameter portion 10b3 of the second end cap 10b, covers a part of the outer periphery of the second end cap 10b, contacts the sleeve receiving portion 10b3 which is a step portion, and does not move any further. It becomes like this. The position where the sleeve 11 contacts the sleeve receiving portion 10b3 and no longer moves is the attachment position where the sleeve 11 described later is fixed to the rotor core 9, the first end cap 10a and the second end cap 10b. Become.

  Since a gap is formed between the inner periphery of the sleeve 11 and the outer periphery of the rotor core 9 and the first end cap 10a, the sleeve 11 is not stabilized as it is and becomes unbalanced during high-speed rotation. Therefore, an adhesive is injected into the gap between the inner periphery of the sleeve 11 and the outer periphery of the rotor core 9 and the first end cap 10a, so that the sleeve 11, the rotor core 9, the first end cap 10a, and the second end cap 10a. The sleeve 11 is stabilized by fixing the end cap 10b.

  When an adhesive is injected into the gap between the inner periphery of the sleeve 11 and the outer periphery of the rotor core 9 and the first end cap 10a, the end portion of the rotor core 9 in the longitudinal direction of the shaft 8 and the first end cap The adhesive enters and is injected also into the end portion on the other end side of the rotor core 9 in the longitudinal direction of the shaft 10a and the minute gap W between the rotor core 9 and the second end cap 10b. Stability during rotation can be improved by filling the gap with an adhesive.

In the embodiment of the present invention, the outer diameter of the rotor core 9 and the outer diameter of the first end cap 10a are the same. However, the outer diameter of the first end cap 10a is made smaller. Alternatively, by reducing the diameter of the outer periphery of the first end cap 10a, the difference from the diameter of the inner periphery of the sleeve 11 can be increased and used as an adhesive reservoir.

  The first end cap 10 a and the second end cap 10 b have the purpose of stabilizing the rotation of the rotor assembly 6 in addition to the purpose of protecting the rotor core 9. As shown in FIG. 3, the shaft 8 of the rotor assembly 6 is rotatably supported by a pair of bearings 13 including a first bearing 13a and a second bearing 13b. Since the electric motor 21 which is a brushless motor rotates at a high speed, if the balance is not good when the rotor assembly 6 rotates, vibration is generated and the electric motor 21 is damaged. Therefore, the first end cap 10a and the second end cap 10b are formed to have the same mass.

However, even if the mass is the same, the rotation balance may be poor when the rotor assembly 6 rotates due to the accuracy of press-fitting and the accuracy of parts. Therefore, the rotation balance may be adjusted by cutting one or both of the first end cap 10a and the second end cap 10b.

The balance adjustment is performed after the sleeve 11, the rotor core 9, the first end cap 10a, and the second end cap 10b are fixed with an adhesive. Therefore, as shown in FIGS. 3 and 5, the first end cap 10 a and the second end cap 10 b are provided with portions where the sleeve 11 is not covered, respectively, and the first portion where the sleeve 11 is not covered is provided. The rotation balance can be adjusted by cutting one or both of the end cap 10a and the second end cap 10b. Since the rotation balance can be adjusted in this way, the rotation balance can be easily stabilized.

  When the first end cap 10a is press-fitted, the shaft from the impeller mounting portion 8d side of the shaft 8 to which the impeller 12 (see FIGS. 8 and 9), which is a fan for generating suction air, which will be described later, shown in FIG. 8 is inserted.

  When moving to the position where the first end cap 10a is fixed, the first end cap 10a passes the position where the pair of bearings 13 shown in FIG. 3 are attached. When the first end cap 10a is press-fitted, as shown in FIG. 6, the first bearing 13a and the second bearing 13b constituting the pair of bearings 13 are not yet attached, and the first end cap 10 It is attached after 10a is press-fitted.

  The first bearing 13a and the second bearing 13b constituting the pair of bearings 13 are attached by being press-fitted into the shaft 8 as will be described later. The attachment of the first bearing 13 a and the second bearing 13 b constituting the pair of bearings 13 greatly contributes to stable rotation of the rotor assembly 6. In order for the first bearing 13a and the second bearing 13b constituting the pair of bearings 13 to be press-fitted satisfactorily, it is necessary to pay close attention to scratches on the surface of the shaft 8.

  As described above, when the first end cap 10a moves to the position where it is fixed, it passes through the position where the first bearing 13a and the second bearing 13b constituting the pair of bearings 13 are attached. Sometimes the surface of the shaft 8 can be damaged.

Therefore, as shown in FIG. 4, the outer diameter φ1 of the shaft large-diameter portion 8a of the shaft 8 at the position where the first end cap 10a and the second end cap 10b are attached constitutes a pair of bearings 13. It is larger (thicker) than the diameter φ2 of the outer periphery of the shaft small diameter portion 8b of the shaft 8 at the position where the first bearing 13a and the second bearing 13b are attached. For example, the outer diameter φ2 of the small shaft diameter portion 8b is 5 mm, and the outer diameter φ1 of the large shaft diameter portion 8a is 5.2 mm.

That is, since the outer diameter of the shaft small diameter portion 8b of the shaft 8 is smaller (thinner) than the inner diameter of the first end cap 10a, the first end cap 10a constitutes a pair of bearings 13. Since the first bearing 13a and the second bearing 13b to be attached can be passed through with sufficient margins, the possibility of damaging the surface of the shaft 8 can be suppressed. Thereby, the first bearing 13a and the second bearing 13b constituting the pair of bearings 13 can be press-fitted satisfactorily, and the rotor assembly 6 can be stably rotated, so that the life of the electric motor 21 can be increased.

  When moving from the small shaft diameter portion 8b of the shaft 8 to the large shaft diameter portion 8a to the position where the first end cap 10a is fixed, the first end cap 10a is inclined from the small shaft diameter portion 8b so that the first end cap 10a can move smoothly. The portion 8c is connected to the shaft large diameter portion 8a.

In other words, the inclined portion 8c changes the diameter from the small shaft diameter portion 8b to the large shaft diameter portion 8a. As shown in FIG. 3, the inclined portion 8c is provided between a position where the pair of bearings 13 and the first end cap 10a are attached. By this inclined portion 8c, the first end cap 10a can be smoothly moved to the large-diameter portion 8a having the same diameter as the position where the first end cap 10a is press-fitted and fixed, and the first end cap 10a is easily press-fitted.

  After the first end cap 10a is press-fitted into the shaft 8, the first bearing 13a is press-fitted into the mounting position of the small shaft diameter portion 8b. Thereafter, the wave washer 14, the spacer 15, and the cushion 16 are inserted.

At this time, the shaft small diameter portion 8b of the shaft 8 penetrates the wave washer 14, the spacer 15, and the cushion 16. However, the wave washer 14, spacer 15 and cushion 16 penetrate through the shaft small diameter portion 8b of the shaft 8 (not shown). The diameter of the inner periphery of the hole is larger than the diameter of the outer periphery of the small shaft diameter portion 8 b of the shaft 8, and the wave washer 14, the spacer 15, and the cushion 16 are not press-fitted into the small shaft diameter portion 8 b of the shaft 8.

Next, the second bearing 13b is press-fitted into the mounting position of the small shaft diameter portion 8b to complete the rotor assembly 6 shown in FIG.

  The wave washer 14 is an annular push spring and applies preload in a direction in which the first bearing 13a and the second bearing 13b are separated from each other. Since the wave washer 14 is attached in an elastically deformed state, the repulsive force acts in a direction in which the first bearing 13 a and the spacer 15 are separated from each other, and the second bearing is interposed via the spacer 15 and the cushion 16. A repulsive force acts in the direction in which 13b is separated.

When the wave washer 14 is attached, a repulsive force acts in advance in the direction in which the first bearing 13a and the second bearing 13b are separated from each other, that is, a preload is applied. The first bearing 13a and the second bearing 13b are ball bearings, and the behavior of the bearing is stabilized by applying preload, and the life of the motor 21 can be extended by stabilizing the rotation of the motor 21.

The cushion 16 is formed of a rubber material such as silicone rubber, urethane rubber, or chloroprene rubber, and receives the preload of the wave washer 14 to prevent the second bearing 13b from creeping during operation of the electric motor described later due to friction. Is.

  The stator 7a of the stator assembly 7 shown in FIG. 2 is configured by winding a coil (not shown) around a stator core (not shown) that is an iron core. The stator 7 a is arranged in the inner space of the frame 5 so as to surround the rotor core 9 of the rotor assembly 6. The stator 7 a is for generating a magnetic force acting on the rotor assembly 6.

  As described above, the frame 5 is a member that forms the outline of the electric motor 21, and has a cylindrical body portion that is open on one end side, and a housing portion 17 that is smaller in diameter than the body portion on the opposite side of the open side. The stator assembly 7 and the rotor core 9 portion of the rotor assembly 6 are housed in a cylindrical body.

  In the housing part 17, the first bearing 13a, the wave washer 14, the spacer 15, the cushion 16, and the second bearing 13b of the rotor assembly 6 are accommodated. The outer peripheral diameter of the spacer 15 can be accommodated in the housing part 17 without applying stress to the spacer 15 with respect to the inner peripheral diameter of the housing part 17. The spacer 15 is fixed in the housing portion 17 by caulking from the outer periphery of the housing portion 17. Thereby, the rotor assembly 6 is fixed to the frame 5. The spacer 15 has been described as being fixed in the housing portion 17 by caulking from the outer periphery of the housing portion 17. However, an adhesive is injected between the inner periphery of the housing portion 17 and the outer periphery of the spacer 15. You may make it fix and fix.

At this time, the first bearing 13 a and the second bearing 13 b are not directly fixed in the housing portion 17 of the frame 5. Since the spacer 15 is sandwiched between the first bearing 13 a and the second bearing 13 b that are press-fitted into the mounting position of the shaft small diameter portion 8 b of the shaft 8, the mounting position is determined, so that the spacer 15 is fixed to the housing portion 17 of the frame 5. As a result, the first bearing 13 a and the second bearing 13 b press-fitted into the shaft small diameter portion 8 b of the shaft 8 so as to sandwich the spacer 15 in the axial direction of the shaft 8 are indirectly in the housing portion 17 of the frame 5. Fixed and contained.

As described above, the inner peripheral diameter of the through hole through which the small shaft diameter portion 8b of the shaft 8 of the spacer 15 passes is larger than the outer diameter of the small shaft diameter portion 8b of the shaft 8, and the spacer 15 has a small shaft diameter of the shaft 8. Since it is not press-fitted into the portion 8 b, the shaft 8 can rotate with respect to the spacer 15.

The first bearing 13 a and the second bearing 13 b are press-fitted into the shaft small diameter portion 8 b of the shaft 8, but the first bearing 13 a and the second bearing 13 b are directly fixed in the housing portion 17 of the frame 5. Absent. Since the spacer 15 is fixed to the housing portion 17 of the frame 5, the rotor assembly 6 is fixed to the frame 5 so that the shaft 8 can rotate.

In the embodiment of the present invention, the spacer 15 is press-fitted into the mounting position of the housing portion 17. However, the spacer 15 may be fixed with an adhesive. The rotor assembly 6 can be fixed to the frame 5 so that the shaft 8 can rotate.

As described above, the second end cap 10b is provided with the sleeve receiving portion 10b3 which is a step portion for preventing the sleeve 11 from coming off, so that it passes through the first end cap 10a and the rotor core 9. The end portion of the sleeve 11 is inserted to the small diameter portion 10b3 of the second end cap 10b, covers a part of the outer periphery of the second end cap 10b, contacts the sleeve receiving portion 10b3 which is a step portion, and more. Stops moving.

The position where the movement has stopped is an attachment position where the sleeve 11 is fixed to the rotor core 9 and the first end cap 10a and the second end cap 10b, so that the sleeve can be attached without using an attachment jig. It can be held in position and can be easily fixed with an adhesive.

Further, since the outer diameters of the first end cap 10a and the rotor core 9 are smaller than or equal to the inner diameter of the sleeve 11, the sleeve 11 can be easily inserted.

Furthermore, since the diameter of the outer periphery excluding the small diameter portion 10b3 of the second end cap 10b is larger than the diameter of the inner periphery of the sleeve 11, the sleeve 11 does not come out and the movement of the sleeve 11 can be easily restricted.

Then, an inclined portion 10a1 is provided at the inner peripheral end portion of the first end cap 10a, and an inclined portion 10b1 is provided at the inner peripheral end portion of the second end cap 10b over the entire circumference. Therefore, the resistance at the time of press-fitting can be relaxed, and the insertion into the shaft 8 can be facilitated as compared with the case where the inner peripheral end is a corner.

  As described above, there is an opening at the front end of the housing portion 17 of the frame 5, and when the rotor assembly 6 is fixed to the frame 5, the shaft 8 of the rotor assembly 6 passes through the opening as shown in FIG. Then protrude. An impeller mounting portion 8 d is provided on the shaft 8 protruding from the housing portion 17 of the frame 5.

(Configuration of electric blower)
Hereinafter, the configuration of the electric blower 1 incorporating the electric motor 21 according to the first embodiment of the present invention will be described with reference to FIGS.
Note that in each drawing, the same reference numerals are given to the same portions or corresponding portions, and a part of the description may be omitted.
The present invention is not limited to the following embodiments, and various modifications and changes can be made without departing from the spirit of the present invention.

  FIG. 7 is an exploded view of the electric blower incorporating the electric motor according to Embodiment 1 of the present invention, and FIG. 8 is a cross-sectional view seen from the side of the electric blower incorporating the electric motor according to Embodiment 1 of the present invention. .

  As shown in FIG. 7, the electric blower 1 incorporating the electric motor 21 according to the first embodiment of the present invention includes a housing of the frame 5 of the electric motor 21 including the rotor assembly 6, the stator assembly 7, and the frame 5. The bracket 4 is attached to the portion 17 side.

Here, the bracket 4 is not yet fixed to the frame 5. The bracket 4 forms a part of the outline of the electric blower 1. The bracket 4 is formed by injection molding of a resin material.

  Next, the diffuser 3 is attached. The diffuser 3 is for increasing the pressure of air generated by an impeller 12 (described later) attached to the electric motor 21, stabilizing it, and sending it efficiently. The diffuser 3 is formed by injection molding of a resin material. After the diffuser 3 is attached, the diffuser 3 and the bracket 4 are fastened to the frame 5 together with screws 18.

  Next, the impeller 12 is attached to the impeller attachment portion 8 d provided on the shaft 8 of the rotor assembly 6 of the electric motor 21 that passes through the housing portion 17, the bracket 4, and the diffuser 3 of the frame 5. The impeller 12 is rotated by the electric motor 21 to generate air blowing. The impeller 12 is formed by injection molding of a resin material. The impeller 12 may be formed of a metal material, but is formed of a resin material in order to reduce the weight of the electric blower 1.

A screw (not shown) is cut at the tip of the impeller mounting portion 8d, and the impeller 12 is fixed to the shaft 8 by inserting the impeller 12 into the impeller mounting portion 8d and fitting and tightening the nut 19 to the screw at the tip. The

  Next, the fan cover 2 is attached so as to cover the impeller 12. The fan cover 2 is a casing that is combined with the bracket 4 to form a ventilation path. The fan cover 2 is formed by injection molding of a resin material.

  As shown in FIG. 8, the fan cover 2 is provided with an intake port 1 a for sucking air from the electric blower 1. The impeller 12 is rotated by the rotation of the electric motor 21, and air is sucked from the intake port 1a. The sucked air is sent out of the electric blower 1 from the exhaust port 1b.

As described above, since the electric blower 1 is configured by incorporating the electric motor 21 which can achieve stable rotation of the rotor assembly 6 and has a long life, the long life can be achieved by stable rotation. The electric blower 1 which can be obtained can be obtained.

(Configuration of vacuum cleaner)
Hereinafter, the structure of the electric vacuum cleaner 100 incorporating the electric blower 1 incorporating the electric motor 21 according to the first embodiment of the present invention will be described with reference to FIGS. 9 to 11.
Note that in each drawing, the same reference numerals are given to the same portions or corresponding portions, and a part of the description may be omitted.
The present invention is not limited to the following embodiments, and various modifications and changes can be made without departing from the spirit of the present invention.

  FIG. 9 is a perspective view showing an external appearance of the electric vacuum cleaner incorporating the electric motor according to Embodiment 1 of the present invention, and FIG. 10 is a side view of the main body of the electric vacuum cleaner incorporating the electric motor according to Embodiment 1 of the present invention. FIG. 11 is a cross-sectional view seen from the side of the main body of the electric vacuum cleaner incorporating the electric motor according to Embodiment 1 of the present invention.

  The vacuum cleaner 100 incorporating the electric blower 1 incorporating the electric motor 21 according to the first embodiment of the present invention includes a main body 101, a dust collecting portion 102, an extension pipe 103, and a suction tool 104, as shown in FIG. Composed.

  The main body 101 is provided with a handle 101b for handling the electric vacuum cleaner 100. In addition, the main body 101 is provided with an operation unit 101c including a switch (not shown) for driving the electric blower 1 when the electric vacuum cleaner 100 is operated.

  The extension pipe 103 is used to connect the main body 101 and the suction tool 104 so as to allow ventilation, and is connected to the main body pipe portion 101a of the main body 101 shown in FIG. The suction tool 104 is connected to the end of the extension pipe 103 opposite to the end connected to the main body pipe 101a. Although not shown, the main body 101 and the suction tool 104 can be connected without using the extension tube 103.

  The suction tool 104 sucks in air containing dust from a surface to be cleaned such as a floor. The suction tool 104 is provided with an opening (not shown) on a surface facing the surface to be cleaned such as a floor. This opening is an opening for sucking in air containing dust.

  As shown in FIG. 11, the dust collection unit 102 has a dust collection chamber 102a. The dust collection chamber 102a is for containing dust. A separation unit 114 is provided in the dust collection chamber 102a. The separation unit 114 is for separating the dust by swirling the air containing the dust. The separated dust is accommodated in the dust collection chamber 102a. The vacuum cleaner 100 is a cyclone type vacuum cleaner.

  A secondary battery 111 that supplies electric power for driving the electric blower 1 is housed inside the main body 101. The vacuum cleaner 100 is a cordless vacuum cleaner that drives the electric blower 1 with the secondary battery 111.

Moreover, the electric blower 1 incorporating the electric motor 21 according to the first embodiment of the present invention is accommodated in the main body 101. The electric blower 1 generates suction air that the vacuum cleaner 100 sucks in air containing dust. The electric blower 1 is the heart of the electric vacuum cleaner 100. The air inlet 1a of the electric blower 1 is disposed so as to be able to ventilate the dust collecting portion 102.

  In the operation of the electric vacuum cleaner 100, when a switch (not shown) for driving the electric blower 1 of the operation unit 101c is turned on, power is supplied from the secondary battery 111 to the electric blower 1. When the electric blower 1 to which electric power is supplied starts driving, suction of air containing dust from the opening of the suction tool 104 is started by the suction air generated by the electric blower 1.

Air containing dust sucked from the opening of the suction tool 104 passes through a ventilation path (not shown) of the extension pipe 103, passes through a suction air path 112 in the main body pipe portion 101 a of the main body 101, and swirls the dust collection portion 102. Sent to the unit 113.

The air containing dust is swirled by the swivel unit 113 and centrifuged, and the separation unit 114 separates the dust and air. The separated dust is accommodated in the dust collection chamber 102 a, and the separated air is sucked into the electric blower 1 from the intake port 1 a of the electric blower 1 and sent out of the electric blower 1 from the exhaust port 1 b of the electric blower 1. Then, the air is discharged out of the main body 101 from a main body exhaust port 101d provided in the main body 101 shown in FIG.

In this way, the vacuum cleaner 100 generates suction air by driving the electric blower 1, sucks air containing dust, separates the dust, and stores it in the dust collecting chamber 102a to perform cleaning. Since the electric vacuum blower 100 incorporating the electric blower 1 incorporating the electric motor 21 according to the first embodiment of the present invention incorporates the electric blower 1 that can achieve a long life by stable rotation, so to speak. Since the lifetime of the electric blower 1 that is the heart of the vacuum cleaner 100 can be increased, the lifetime of the vacuum cleaner 100 can also be increased.

  DESCRIPTION OF SYMBOLS 1 Electric blower, 1a Intake port, 1b Exhaust port, 2 Fan cover, 3 Diffuser, 4 Bracket, 5 Frame, 6 Rotor assembly, 7 Stator assembly, 7a Stator, 8 shaft, 8a shaft large diameter part, 8b shaft small diameter Portion, 8c inclined portion, 8d impeller mounting portion, 9 rotor core (plastic magnet), 10a first end cap, 10a1 inclined portion, 10a2 stepped portion, 10b second end cap, 10b1 inclined portion, 10b2 small diameter portion, 10b3 Sleeve receiving portion (stepped portion), 11 sleeve, 12 impeller, 13 pair of bearings, 13a first bearing (stepped portion side bearing), 13b second bearing (impeller side bearing), 14 wave washer, 15 spacer, 16 Cushion, 17 Housing part, 17a Tip part, 17b Mouth, 18 screw, 19 nut, 21 electric motor, 100 vacuum cleaner, 101 main body, 101a main body pipe section, 101b handle, 101c operation section, 101d main body exhaust port, 102 dust collection section, 102a dust collection chamber, 103 extension pipe, 104 Suction tool, 111 Secondary battery, 112 Suction air passage, 113 Swivel part, 114 Separation part.

Claims (10)

A shaft that is rotatably supported;
A rotor core having a plurality of magnetic poles attached to or integrally formed with the outer periphery of the shaft;
A pair of bearings attached to the outer periphery of the shaft for rotatably supporting the shaft;
With
When viewed in the longitudinal direction of the shaft, a first end cap and a second end cap are respectively attached to positions that become both ends of the rotor core;
A cylindrical sleeve is provided so as to cover the outer periphery of the rotor core and to cover a part of the outer periphery of the first end cap and the second end cap,
The electric motor in which the second end cap attached to the end portion side of the shaft is provided with a step portion that restricts the sleeve from moving toward the end portion of the shaft.   A diameter of an outer periphery of the first end cap attached to the pair of bearings is the same as or smaller than an inner diameter of the sleeve, and a second end cap attached to the end of the shaft. 2. The electric motor according to claim 1, wherein a diameter of an outer periphery of the shaft from the step portion is larger than an inner diameter of the sleeve. The first end cap and the second end cap are attached by press-fitting into the shaft,
3. The electric motor according to claim 1, wherein inner end portions of the first end cap and the second end cap are provided with inclined portions.   The electric motor according to any one of claims 1 to 3, wherein the first end cap and the second end cap have the same mass.   The electric motor according to any one of claims 1 to 4, wherein an adhesive is injected between an outer periphery of the rotor core and an inner periphery of the sleeve.   When the first end cap and the second end cap are press-fitted to a position where the first end cap and the second end cap are held by the shaft, the end portion of the first end cap near the rotor core and one end of the rotor core, and the rotor The electric motor according to any one of claims 1 to 5, wherein a minimal gap is provided between an end portion of the second end cap near the core and the other end of the rotor core.   Adhesive between the end of the first end cap near the rotor core and one end of the rotor core, and between the end of the second end cap near the rotor core and the other end of the rotor core The electric motor according to claim 6 in which is injected.   The shaft of the shaft to which the rotor core is attached is formed by scraping either one or both of the portion of the first end cap that is not covered by the sleeve and / or the portion of the second end cap that is not covered by the sleeve. The electric motor according to any one of claims 1 to 7, wherein a rotation balance is adjusted. The electric motor according to any one of claims 1 to 8,
An impeller attached to one end of the shaft of the electric motor for generating airflow;
Electric blower equipped with.   A vacuum cleaner comprising the electric blower according to claim 9.

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