TWI546454B - Electric blowers and vacuum cleaners - Google Patents

Description

Electric blower and vacuum cleaner

The present invention relates to an electric blower and a vacuum cleaner.

In general, a DC blower motor is used as an electric blower for use in a vacuum cleaner in order to reduce vibration and noise (for example, refer to Patent Document 1).

In the rotor assembly of the electric blower of Patent Document 1, a magnet is attached to one end of the shaft, and an impeller is attached to the other end of the shaft. A bearing bore is mounted between the magnet of the shaft and the impeller. The bearing bore includes a pair of bearings that are pressed into the shaft, a preload spring that is disposed between the bearings, and an outer casing that is externally fitted to the pair of bearings.

This rotor assembly system is assembled into the outer casing after assembly.

[prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Publication No. 2012-518751

The electric blower of Patent Document 1 mounts a magnet to a shaft by an adhesive. Thereby, a gap is formed between the magnet and the shaft due to the adhesion of the adhesive. Therefore, it is difficult to adjust the homocentricity between the magnet and the shaft, and there is a problem that vibration and noise are generated because the same core degree is lowered.

* Since the structure of "impeller", "shell and rotor" is not installed in the above request, the problem of "offset from the same core of the shaft and the impeller" and "the deviation of the core between the outer casing and the rotor" is not Recorded.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to provide an electric blower and a vacuum cleaner which can reduce vibration and noise.

The electric blower according to the present invention is characterized in that it includes a rotor having a shaft that is rotatably provided and a rare earth-based bonded magnet integrally formed on the shaft.

Further, the vacuum cleaner of the present invention is characterized in that it is provided with the above-described electric blower.

According to the present invention, since the bonded magnet is integrally formed on the shaft, the same core degree of the shaft and the bonded magnet can be ensured with high precision.

According to the present invention, an electric blower and a vacuum cleaner capable of reducing vibration and noise can be obtained.

1‧‧‧ vacuum cleaner

10‧‧‧Electric blower

20‧‧‧ Shell

22‧‧‧ bearing cap

30‧‧‧Rotor assembly (rotor)

31‧‧‧Axis

32‧‧‧Rotor core (bonded magnet)

33‧‧‧ bearing assembly

34‧‧‧ Impeller

36, 37‧‧‧ bearing

40‧‧‧stator assembly

41‧‧‧Silker core

Di‧‧‧ outer diameter of the impeller

Db‧‧‧ outer diameter of the bearing

Dc‧‧‧Minimum inner diameter of bearing cap

Dm‧‧‧ outer diameter of the rotor core

Fig. 1 is a perspective view showing the appearance of a vacuum cleaner to which an electric blower according to the present embodiment is applied.

Fig. 2 is a cross-sectional view schematically showing the cleaner body.

Fig. 3 is a cross-sectional view showing the electric blower of the embodiment.

Fig. 4 is a perspective view showing a portion of the electric blower cut away in cross section.

Fig. 5(a) is a side view of the rotor assembly, and Fig. 5(b) is a cross-sectional view of the rotor assembly.

Fig. 6(a) is an explanatory view showing the assembly of the rotor assembly to the outer casing, (b) is an enlarged cross-sectional view showing one end portion of the bearing cap, and (c) is an explanatory view showing the same assembled dice.

7(a) to 7(c) are explanatory views showing the assembly procedure of the rotor assembly.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, when referring to the "front and rear" of the electric blower, the direction shown in Fig. 3 is used as a reference.

As shown in Fig. 1, the cleaner 1 includes a cleaner body 2, a hose 3, an operation tube 4 provided with a hand-held operation SW, an extension tube 5 as a joint tube, and first and second suction members 6 and 7. .

As shown in FIG. 2, the inside of the cleaner body 2 is arranged to: attract the attraction The generated electric blower 10, the paper bag 8 (collection member) disposed in the dust collecting chamber 2c for collecting dust sucked by the suction force of the electric blower 10, and the filter 9 for passing air through which the dust is removed through the paper bag 8 Wait.

The electric blower 10 is housed in the anti-vibration rubber 2b. The electric blower chamber 2a of the cleaner body 2. As shown in FIG. 3, the electric blower 10 is provided with the outer casing 20, the rotor assembly (rotor) 30, and the stator assembly 40.

〔shell〕

As shown in FIG. 3, the outer casing 20 is made of synthetic resin and has a support portion 21 that supports the rotor assembly 30. The support portion 21 has a substantially cylindrical shape and is located inside the front portion of the outer casing 20. A cylindrical bearing cap 22 made of metal is fixed to the inside of the support portion 21. The bearing cap 22 is integrally formed on the outer casing 20 (support portion 21). In the present embodiment, the outer casing 20 is formed by insert molding the bearing cap 22 as an insert. Bearings 36 and 37 provided in the rotor assembly 30 are fitted into the inner surface of the bearing cap 22.

A front end portion of the support portion 21 is formed to extend in the axial direction Screw hole 21a. The fixing screw 21b can be screwed into the screw hole 21a. At the front end portion of the support portion 21, a diffusion plate 25 (static blade) is fixedly provided by screwing of the fixing screw 21b.

On the outer peripheral surface of the rear portion of the outer casing 20, a radial extension is formed. Extending extension 23. The extension portion 23 supports the rear end portion of the outer casing 26 that is disposed around the outer casing 20. A space in which the stator assembly 40 is disposed is formed in the inner space of the rear portion of the outer casing 20.

[rotor assembly]

As shown in FIGS. 5( a ) and 5 ( b ), the rotor assembly 30 includes a shaft 31 , a rotor core 32 , a bearing assembly 33 , and an impeller 34 . The rotor core 32, the bearing assembly 33, and the impeller 34 are attached to the shaft 31.

The shaft 31 extends in the front-rear direction and is formed in a cylindrical shape having a stage. The rotor core 32 is formed around one end of the shaft 31, that is, around the rear portion 31a, and is composed of a rare earth-based bonded magnet. The rare earth-based bonded magnet can be prepared by mixing a rare earth-based magnetic powder and an organic binder. As the rare earth-based bonded magnet, for example, a neodymium iron nitrogen magnet or the like can be used.

The rotor core 32 is integrally formed on the shaft 31. In the present embodiment, the rotor core 32 is molded by insert molding. That is, the rotor core 32 is integrally formed on the shaft 31, and there is no gap caused by the adhesive interposed therebetween. Further, since the neodymium iron nitrogen magnet is stronger than the normal (sintered) ferrite magnet and is also easy to process, it is suitable as the electric blower 10 of the vacuum cleaner 1 which is required to be small and rotates at a high speed.

Further, ferrite processing is performed on the outer peripheral surface of the rear portion 31a of the shaft 31. The rotor core 32 can be strongly bonded to the shaft 31 by knurling.

The bearing assembly 33 is a member for fixing the rotor assembly 30 to the outer casing 20, and is disposed between the rotor core 32 and the impeller 34. The bearing assembly 33 includes a pair of bearings 36 and 37, a spacer 38, and a spring 39.

The same is used for the pair of bearings 36, 37. The spacer 38 is responsible for arranging a pair of cylindrical bearings 36 and 37 with a predetermined distance therebetween. Business. The spring 39 is a coil spring that surrounds the spacer 38, and is disposed in a compressed state, and abuts against the outer rings of the respective bearings 36 and 37 to impart a preload.

The impeller 34 is made of synthetic resin and is directly coupled to the shaft 31. The other end side is also the front part. The impeller 34 is a centrifugal impeller that uses centrifugal force, and the pressure rise in the impeller 34 is increased when rotating at a high speed, and the air is taken in from the suction portion 26c formed in the opening of the lid portion 26b of the outer casing 26. The sucked air is discharged to the outer peripheral side by the high-speed air flow by the impeller 34 (see FIGS. 3 and 4). The air flow discharged from the impeller 34 is guided to the diffusion plate 25. The diffusion plate 25 is formed with a diffusion plate flow path that guides the flow of air discharged from the impeller 34 in the outer circumferential direction. As shown in FIG. 4, the air flow passing through the diffuser flow path is guided to the space S1 of the outer casing 20 and the outer casing 26 (main body portion 26a), and is led out from the outlet port 23a to the outside of the electric blower 10. The outlet port 23a is formed at the extension portion 23 of the outer casing 20.

Further, the air flow guided to the space S1 flows into the outer casing 20 through the slit S2 of the outer casing 20, and is passed between the rotor core 32 and the stator assembly 40 and between the wires (not shown) of the stator assembly 40, and is led to The outside of the electric blower 10. Thereby, each part in the outer casing 20 is cooled.

A metal support sleeve 34a formed by sintering or the like is attached to the center portion of the impeller 34. The support sleeve 34a has an inner peripheral surface into which the shaft 31 is pressed. This support sleeve 34a is embedded in the impeller 34. The impeller 34 is fixed to the front portion of the shaft 31 by pressing the shaft 31 into the support sleeve 34a.

[stator assembly]

As shown in FIG. 3, the stator assembly 40 is disposed in the rear inner space of the outer casing 20. The stator assembly 40 includes a stator core 41 that is disposed on the opposite side of the rotor core 32. A wire (not shown) is wound around the stator core 41 to form a phase winding wire. The phase winding wire is electrically connected to a circuit portion (not shown) provided in the electric blower 10.

As shown in FIG. 6, in the electric blower 10 as above, When the outer diameter of the impeller 34 (outer diameter of the bottom portion 34c) is Di, the outer diameter of the bearings 36, 37 is Db, the minimum inner diameter of the bearing cap 22 is Dc, and the outer diameter of the rotor core 32 is Dm, the relationship is set. Di>Db>Dc>Dm.

As such, the outer diameter Db of the bearings 36, 37 is greater than that of the impeller 34 The outer diameter Di is small, and the minimum inner diameter Dc of the bearing cap 22 (the inner diameter of the opening edge 22b of the one end opening 22a, see FIG. 6(b)) is smaller than the outer diameter Db, and the outer diameter Dm of the rotor core 32 is smaller than the minimum inner diameter. Since Dc is small, the rotor core 32 inserted into the bearing cap 22 is inserted into the inside of the stator assembly 40 through a portion of the minimum inner diameter Dc of the one end opening 22a (refer to FIG. 3). At the same time, the bearing assembly 33 is inserted into the bearing cap 22, and the bearing 36 on the rear side abuts against the opening edge 22b of the bearing cap 22 from the inner side (front side), and is positioned at the opening edge 22b (see FIG. 6(c)).

Next, the manufacture and assembly of the rotor assembly 30 will be described. First, as shown in FIG. 7(a), the rotor core 32 is integrally molded to the rear portion 31a of the shaft 31 by insert molding. At this time, it is possible to have a slope for magnetizing the rotor core 32 by insert molding while applying a magnetic field. Further, the impeller 34 is additionally formed by insert molding the support sleeve 34a as an insert.

Thereafter, as shown in FIG. 7(b), at the center periphery of the shaft 31 The bearing assembly 33 is attached to the surface 31c. In this case, the bearing 36 on the rear side is press-fitted and fixed to the shaft 31, and after assembling the spacer 38 and the spring 39, the bearing 37 on the front side is press-fitted. The bearing 36 on the rear side is positioned at a predetermined position by the projection 31b of the shaft 31.

Then, as shown in FIG. 7(c), the shaft is placed via the spacer 35. The front portion of the 31 is pressed into the support sleeve 34a of the impeller 34, and the impeller 34 is fixed to the shaft 31 by fastening. The inner surface of the impeller 34-based support portion 34b abuts on the inclined portion 31e at the front portion of the shaft 31 and the small-diameter portion 31d, and is positioned at the front portion of the shaft 31.

The rotor assembly 30 is assembled according to the above.

Further, as shown in FIG. 5(b), the support sleeve 34a is disposed at a position close to the bottom portion 34c of the impeller 34 and is fixed to the shaft 31. Thereby, it is possible to appropriately suppress the wobble of the center of the intersection Y1 of the bottom portion 34c and the center of the shaft 31 (the shaking of the impeller 34 in the direction of the arrow X1 in the figure).

Next, the rotational balance of the rotor assembly 30 is adjusted. A special tool is used for the adjustment, and the rotor assembly 30 is actually rotated at a high speed to observe the balance. For example, remove the imbalance and so on to adjust the balance. Further, since the magnetization is not performed at this point, the rotor core 32 can be removed to achieve balance.

After the adjustment balance is completed, magnetization is performed to make the rotor core 32 have a magnetic force. After the magnetization is completed, the rotor assembly 30 is assembled in the outer casing 20. That is, the rotor assembly 30 is assembled into the outer casing 20 after adjusting the balance, so that it can be maintained well. In the balanced state, the electric blower 10 is assembled.

Further, as shown in FIG. 6(a), the diffuser 25 is fixed to the outer casing 20 in advance, and the rotor assembly 30 is inserted into the outer casing 20 through the diffuser 25.

The rotor assembly 30 and the bearing cover 22 are as described above, and the bearing The outer diameter Db of 36, 37 is smaller than the outer diameter Di of the impeller 34, the minimum inner diameter Dc of the bearing cap 22 is smaller than the outer diameter Db, and the outer diameter Dm of the rotor core 32 is smaller than the minimum inner diameter Dc, so that the rotor can be assembled The body 30 is smoothly assembled to the outer casing 20 (bearing cover 22) (refer to Fig. 6(c)).

The bearings 36, 37 can be secured to the bearing cap 22 by an adhesive.

Electric blower according to the embodiment described above 10. Since the rotor core 32 is formed on the shaft 31 by insert molding (integral molding), the same core degree of the shaft 31 and the rotor core 32 can be improved without requiring a gap which is conventionally provided for the adhesive. Therefore, the electric blower 10 which can reduce vibration and noise is obtained.

Further, a knurling is applied to the surface of the rear portion 31a of the shaft 31. The rotor core 32 can be strongly coupled to the shaft 31, so that the rotor core 32 can be prevented from being idling.

Moreover, the impeller 34 is press-fitted by the support sleeve 34a. It is fixed to the shaft 31 by fastening and fitting, and the same core degree of the shaft 31 and the impeller 34 can be raised without requiring a gap which is conventionally provided for the adhesive. Therefore, the electric blower 10 which can reduce vibration and noise is obtained.

In this manner, the rotor assembly 30 having excellent core strength is formed by insert molding and press-fitting without using an adhesive, and thus the electric blower 10 that reduces vibration and noise is obtained.

The rotor assembly 30 is assembled into the outer casing 20 after adjusting the balance of the entire body, so that the electric blower 10 that reduces vibration and noise is obtained.

Further, in the rotor assembly 30 and the bearing cap 22, the outer diameter Db of the bearings 36, 37 is smaller than the outer diameter Di of the impeller 34, and the minimum inner diameter Dc of the bearing cap 22 is smaller than the outer diameter Db, and the outer diameter of the rotor core 32 is further increased. Since Dm is smaller than the minimum inner diameter Dc, the assembly of the outer casing 20 by the rotor assembly 30 is smooth and excellent in assemblability. Moreover, since the assemblability is excellent, the balance of the rotor assembly 30 adjusted before assembly can be favorably maintained after assembly.

In the above embodiment, the rotor core 32 is provided on the rear portion 31a of the shaft 31. However, the present invention is not limited thereto, and may be integrally formed at another position of the shaft 31.

Further, the shape of the outer casing 20 or the like may be any shape as long as it can support the rotor assembly 30.

10‧‧‧Electric blower

20‧‧‧ Shell

21‧‧‧Support

21a‧‧‧ screw holes

21b‧‧‧ fixing screws

22‧‧‧ bearing cap

22a‧‧‧ Opening

23‧‧‧Extension

25‧‧‧Diffuser

26‧‧‧Outer box

26a‧‧‧ Main body

26b‧‧‧Cap

26c‧‧Inhalation

30‧‧‧Rotor assembly (rotor)

31‧‧‧Axis

32‧‧‧Rotor core (bonded magnet)

33‧‧‧ bearing assembly

34‧‧‧ Impeller

34a‧‧‧Support sleeve

35, 38‧‧‧ spacers

36, 37‧‧‧ bearing

39‧‧‧ Spring

40‧‧‧stator assembly

41‧‧‧Silker core

Claims (4)

An electric blower characterized by comprising a rotor having a shaft that is rotatably provided, and a rare earth-based bonded magnet integrally formed on the shaft, wherein the rare earth-based bonded magnet is integrally formed at one end of the shaft The rotor includes: an impeller attached to the other end of the shaft; and a bearing attached to the shaft between the rare earth-based bonded magnet and the impeller, and a bearing cover provided to support the bearing In the outer casing, when the outer diameter of the impeller is Di, the outer diameter of the bearing is Db, the minimum inner diameter of the bearing cap is Dc, and the outer diameter of the rare earth bonded magnet is Dm, Di>Db>Dc>Dm is satisfied. relationship. An electric blower characterized in that it has a rotor having a shaft that is rotatably provided, and a rare earth-based bonded magnet integrally formed on the shaft, and has a support sleeve that presses the shaft into the shaft The inner circumferential surface, the support sleeve is integrally formed on the impeller. The electric blower of claim 1, wherein the bearing cap is integrally formed in the outer casing. A vacuum cleaner comprising the electric blower according to any one of claims 1 to 3.