JPH0338479Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electric blower used in a vacuum cleaner or the like.

[Prior Art] In the conventional electric blower shown in FIG. 6, a rotor 1 and a fan 3 attached to the rotor shaft 2 are rotated by operating the motor. Then, the air sucked in from the suction port 4a of the fan cover 4 passes through the fan 3 as shown by the arrow and is discharged from there, and then passes through the inlet 5a of the baffle plate 5 and the inside of the case end plate 6. The main body 7 is guided into the case main body 7 through the hole 6a.
The air is circulated through the air. In such an electric blower, a dustproof disk 8 is attached to the rotor shaft 2 with a retaining ring 9. As shown in FIG. 7, this dustproof disk 8 is provided on the case end plate 6 and covers an opening facing into the case body 7 of a bearing housing 6b containing a bearing 10 that supports the rotor shaft 2. This ensures that the bearing part is dust-proof. In order to prevent dust by rotating together with the rotary shaft 2, the dust-proof disc 8 has a stepped part 8a in the middle part and is spaced apart from the outer ring 10a of the bearing 10, and its periphery is connected to the opening of the housing 6b. They are placed close to each other with a slight gap G between them.

[Problems to be solved by the invention] By the way, in the operating state of the electric blower,
The fan 3 and the rectifier plate 5 are
While the air in the gap A between the case body 7 and the case body 7 is sucked out toward the outer circumferential side, air is sent into the case body 7 as described above. As a result, the pressure in the gap A becomes low, and the pressure in the portion B below the dustproof disc 8 in FIGS. 6 and 7 becomes high.

In the conventional structure described above, the opposing area between the outer circumferential end of the dustproof disk 8 and the bearing housing 6b is extremely small, and therefore the flow path resistance of the gap G is small. As a result, a part of the blown air flow easily enters the bearing 10 through the gap G and flows back into the gap A due to the above pressure difference, so that the dust contained in the intruding air can be transferred to the grease inside the bearing 10. It adheres to things such as. This poses problems in that noise may be generated and the bearing 10 may seize.

[Means for Solving the Problems] The present invention provides a case end plate with an annular convex portion that surrounds a bearing housing provided thereon and is concentric with the housing, so that the case end plate rotates with the rotor shaft and the bearing housing By providing an annular convex cover which is curved along the annular convex part and forms a minute gap between the annular convex part and the dust-proof disc covering the opening of the conventional This problem was solved.

[Function] In the electric blower equipped with the above-mentioned solving means, the minute gap between the dust-proof disk that protects the bearing portion through which the rotor shaft passes and the case end plate is connected to the annular convex portion of the case end plate. , and the annular convex cover of the dust-proof disk, which is curved so as to overlap with the convex part, so that it can be secured for a long time. Furthermore, the annular convex portion and the annular convex portion cover allow the above
Since the gap is bent, the flow path resistance of this gap is large. This prevents the air from circulating through the bearing due to the pressure difference between the inside of the motor case and the outside of the bearing on the fan side.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

In the figure, reference numeral 11 denotes a metal case body that is approximately cylindrical with a bottom and has an annular flat portion 12 integrally provided at one end of the opening edge. A metal case end plate 13 is attached to one open end of the main body 11, and the case main body 11 and the case end plate 13 form a motor case 14.

A bearing housing 16 containing a bearing 15 is integrally provided at the center of the bottom wall of the case body 11. A bearing 1 is also provided in the center of the case end plate 13.
A bearing housing 18 containing 7 is integrally provided. The motor case 14 has a bearing 1.
The rotor shaft 19 is supported by the rotor 20
is housed, and a stator 21 is housed surrounding the rotor 20.

The case end plate 13, which is provided to cross the opening of the case body 11 in the radial direction, has a substantially band-like planar shape as shown in FIG. 4, and has a bearing housing formed in the center thereof. Both sides of the housing 18 are inclined downward in the figure toward the fixed side end portion from the housing 18 to the annular plane portion 12. Along with this, the case end plate 13 has an annular protrusion 22 surrounding the bearing housing 18 and concentric with the housing 18.
are integrally bent. This annular convex portion 22
For example, it protrudes toward the bottom side of the case body 11, and its cross section has a curved shape as illustrated in FIG.

A dustproof disk 23 is attached to the rotor shaft 19 to cover the opening of the bearing housing 18 facing into the case body 11. This disk 23
is a molded product made of metal or synthetic resin, and is sandwiched between the retaining ring 24 and the inner ring 17a of the bearing 17 so as to be rotated together with the rotor shaft 19. Further, an annular convex cover 25 is provided on the peripheral edge side of the dustproof disc 23. Convex cover 2
5 is a convex portion 2 extending over the entire annular convex portion 22.
2, and covers the annular protrusion 22 with a minute gap g formed therebetween.

Further, a commutator 26 is attached to the rotor shaft 19, and a centrifugal fan 27 is attached with a nut 28 to the end of the shaft 19 passing through the bearing 17 and the bearing housing 18. Then, this fan 27 and the case end plate 1
3, a flow regulating plate 29 made of synthetic resin is provided which is screwed to the case end plate 13 or the like.
This rectifier plate 29 covers one end opening of the case body 11, and in this embodiment, accommodates the case end plate 13 inside. Also, 30 in Figure 3
1 is a fan cover having an intake port 30a in the center, which is fitted into a fitting cylindrical portion 31 that covers the fan 27 and the rectifying plate 29 and continues to the annular flat portion 12. In addition, 32 in the figure is an air passage in the case formed between the case body 11 and the stator 21;
3 is an exhaust hole, and 34 is a brush device.

In the above structure, when the drive motor formed by the motor case 14, bearings 15, 17, rotor 20, and stator 21 is operated, the rotor shaft 19 of the rotor 20, the dustproof disc 23, and the fan 27 is rotated. Therefore, due to the rotation of the fan 27, as shown by the arrow in FIG. An air blowing effect can be obtained by passing through the vent hole, the case internal air passage 32, and the exhaust hole 33 in the order described.

By the way, in the electric blower having the above structure, the dust-proof disc 23 that rotates together with the rotor shaft 19 is provided to cover the opening of the bearing housing 18, and the annular convex portion of the dust-proof disc 23 Since the cover 25 surrounds the bearing housing 18 and covers the annular convex portion 22 provided on the case end plate 13, the bearing 17 is protected from dust.

In other words, due to the overlapping relationship between the annular convex portion 22 and the convex portion cover 25 as described above, the length of the minute gap g formed between them is ensured to be long, and both are not bent. The gap g between the annular protrusion 22 and the annular protrusion cover 25 has a curved structure. Therefore, the passage resistance of the long and curved gap g as described above is large.

Therefore, in the above-mentioned air blowing operation, the bearing 17
Although the pressure inside the motor case 14 is higher than the pressure outside the motor case 14 of the bearing 17 and on the fan 27 side, in this embodiment, especially the structure of the case end plate 13 and its rectifying plate 29
This pressure difference prevents the air from circulating through the bearing 17 within the bearing housing 18, even though the inward placement tends to direct air to the open side of the bearing housing 18. This prevents dust contained in the wind from adhering to the bearing 17.

Due to the above-described dust-proofing effect, it is possible to prevent the generation of noise in the bearing 17 due to the intrusion of dust, and it is also possible to prevent the bearing 17 from seizing. Moreover, by preventing the circulation of the airflow as described above, the airflow performance can also be improved.

Further, in the present invention, as in the other embodiment shown in FIG. It may also be carried out by attaching it to By doing this, it is possible to reduce the number of parts and simplify the mounting structure of the dustproof disc 23, as well as to
3a prevents the surface of the dust-proof disc 23 from touching, so it is possible to prevent the convex cover 25 from coming into contact with the case end plate 13, and to further improve the dust-proof effect by narrowing the width of the gap g. can.

Furthermore, in the present invention, the annular convex portion 22 and the convex portion cover 25 may be provided so as to protrude in the same direction as the direction in which the bearing housing 18 protrudes. Moreover, a plurality of annular convex portions 22 and convex portion covers 25 may be provided.

In addition, when implementing the present invention, unless it is contrary to the gist of the invention, the case body, case end plate,
The specific structure, shape, position, material, etc. of the stator, rotor, rotor shaft, fan, bearing housing, bearing, annular protrusion, dustproof disc, protrusion cover, etc. are limited to the above embodiments. Of course, the present invention can be configured and implemented in various ways without being limited to the above.

[Effects of the invention] According to the present invention, which has the structure described in the claims for utility model registration, the annular protrusion of the case end plate and the annular protrusion cover of the dustproof disc create a space between them. The minute gap provided is long and curved to increase the flow path resistance between the edges, so a part of the airflow flowing into the motor case is transferred to the bearing attached to the case end plate. The dust-proofing performance of the bearing can be improved by preventing the flow from flowing back through the fan to the fan side, thereby preventing seizure accidents of the bearing and noise generation at the bearing, and its practical effects. is large.

[Brief explanation of the drawing]

1 to 4 show an electric blower for a vacuum cleaner according to an embodiment of the present invention, FIG. 1 is a cross-sectional view of the main parts, FIG. 2 is a perspective view of the dust-proof disc turned over,
FIG. 3 is a partially sectional side view of the whole, and FIG. 4 is a partially perspective view. FIG. 5 is a sectional view showing the main parts of another embodiment of the present invention. Figures 6 and 7
The figures show a conventional example, with FIG. 6 being a partially sectional side view of the whole, and FIG. 7 being a partially sectional view. 11...Case body, 13...Case end plate,
14...Motor case, 17...Bearing, 18...
Bearing housing, 19... Rotor shaft, 20... Rotor, 21... Stator, 22... Annular convex portion, 23
...Dust-proof disc, 25...Protrusion cover, g...Gap.

Claims (1)

[Scope of utility model registration request] A stator and a rotor are housed in a motor case consisting of a case body and a case end plate attached to one open end of the motor case, and the rotor of the rotor passes through a bearing built into a bearing housing of the case end plate. A dust-proof disk is attached to the shaft to cover an opening facing into the case body of the bearing housing, and a fan is attached to the rotor shaft so that air discharged from the fan is circulated inside the motor case. In the electric blower, the case end plate is provided with an annular protrusion that surrounds the bearing housing and is concentric with the housing, and the dustproof disc is curved along the annular protrusion and has the annular protrusion. An electric blower characterized in that an annular convex cover is provided to form a small gap between the convex part and the convex part.