JPH06200898A - Motor-driven air blower - Google Patents

Abstract

PURPOSE:To provide a motor-driven air blower allowing to reduce a current due to blast operation and to reduce its axial dimension. CONSTITUTION:A motor-driven air blower is of wet and dry type and is used for a vacuum cleaner. A fan cover 43 is supported on a fan cover-mounting wall projected with the outside of a stator 15 surrounded. An internal air course compartment 45 is positioned between the wall and a centrifugal blast fan 41 mounted on one end of the rotor shaft 22 of a rotor 21 and covered with a cover 43. The compartment 45 has a ring partition wall 77 adjacent to the face of the wall at the fan side 41 and an outer peripheral wall 48. On the wall, a blast exhaust part 49 passing air discharged from the blast fan 41 to the rotor 21 in the axial direction is provided at the outside of the partition wall 47. The tip of the outer peripheral wall 48 facing the fan cover 43 is approached to the wall to increase air course length reaching the exhaust part 49 from the fan 41.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric blower used in, for example, a wet and dry type vacuum cleaner.

[0002]

2. Description of the Related Art An electric blower for a wet-and-dry type vacuum cleaner is provided with a centrifugal blower fan for sucking and blowing air containing water at one end of a rotor shaft and the other end of the rotor shaft. A cooling fan that sends air for cooling the stator and the rotor is attached to the section. Electric blowers of this type are known from Japanese Utility Model Publication No. 59-1644 and Japanese Patent Publication No. 57-122835.

As disclosed in these publications, conventionally, a large number of exhaust holes are formed at intervals in the circumferential direction on a cover peripheral wall of a fan cover which covers a blower fan, and these exhaust holes are provided with these exhaust holes. The air discharged from the blower fan is discharged to the outside of the peripheral wall of the cover so that the stator and the rotor are not exposed to the air containing water.

[0004]

By the way, since the outlet of the blower fan and the cover peripheral wall of the fan cover are closely opposed to each other, the air discharged from the blower fan is discharged through the cover peripheral wall as described above. The conventional configuration has a problem that a large wind noise is generated because the very high-speed wind, which has a strong momentum immediately after being discharged from the blower fan, directly passes through the exhaust hole.

Further, in the electric blower, an annular support rubber is fitted to an outer surface of a corner portion formed by a portion where the cover peripheral wall and the cover end wall of the fan cover are continuous, and is supported through this rubber. Has become. Therefore, in the conventional configuration in which there is one blower fan and the exhaust holes are formed in the cover peripheral wall of the fan cover, the depth of fitting of the support rubber to the corners is adjusted so that the support rubber does not block the exhaust holes. It needs to be shallow.

Therefore, the mounting state of the support rubber becomes unstable, and the support rubber is liable to drop when the electric blower is assembled in the cleaner body of the electric vacuum cleaner, which is inconvenient for assembly. Therefore, conventionally, the blower fans are provided in multiple stages to increase the axial dimension of the fan cover, thereby ensuring a large fitting depth of the support rubber with respect to the corner portion and blocking the exhaust hole with this rubber. Are forced to avoid. Therefore, the conventional electric blower of this kind also has a problem that the axial dimension is long.

An object of the present invention is to provide an electric blower capable of reducing the noise generated by the blowing operation of a blower fan and shortening the axial dimension thereof.

[0008]

According to the present invention, a centrifugal blower fan is attached to one end of a rotor shaft of a rotor arranged inside a stator, and the stator and the stator are attached to the other end of the rotor shaft. A cooling fan for cooling the rotor was attached, a fan cover mounting wall surrounding the stator and projecting outward was provided on the blower fan side, and a fan cover for covering the blower fan was attached to the mounting wall. It is applied to electric blowers.

In order to achieve the above object, an internal air passage partition having an annular partition wall that abuts against the surface of the fan cover mounting wall on the side of the blower fan is provided with the fan cover mounting wall and the blower fan. And an air exhaust unit for exhausting the air discharged from the air blowing fan in the axial direction of the rotor shaft on the fan cover mounting wall, the air exhaust unit being located outside the annular partition wall. Also, an outer peripheral wall facing the inner peripheral surface of the fan cover is provided on the peripheral edge of the internal air passage partitioning body located radially outside the fan cover mounting wall so as to project toward the fan cover mounting wall.

[0010]

In the structure of the present invention, the blower / exhaust section is provided not on the peripheral wall of the fan cover but on the fan cover mounting wall that surrounds the stator and projects outward. Therefore, the blower / exhaust section and the outlet of the blower fan are connected to each other. A long distance can be secured. Then, the fan cover receives the air discharged in the centrifugal direction from the discharge port on the inner surface of the cover peripheral wall, and changes the direction of the air toward the air exhaust unit. Moreover, the internal air passage partition prevents the air blown by the air blower fan from reaching the stator side, and the outer peripheral wall thereof blows air together with the cover peripheral wall on the outer side in the radial direction of the fan cover mounting wall with respect to the air blower exhaust part. By guiding to the exhaust section side, a longer air passage between the blower exhaust section and the outlet of the blower fan is secured. The blower / exhaust unit exhausts the wind, which is changed in direction by the fan cover and guided between the outer peripheral wall and the annular partition wall, in the axial direction of the rotor.

Therefore, a very high-velocity, high-speed wind does not directly pass through the blower / exhaust unit, and the wind force can be killed and passed through the blower / exhaust unit.

Further, since the blower / exhaust section is provided on the fan cover mounting wall, the blower / exhaust section is not blocked by the support rubber fitted to the outside of the fan cover.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The first embodiment of the present invention will be described below with reference to FIGS.
An example will be described. Reference numeral 1 in FIGS. 1, 4, and 13
The electric motor frame shown by is integrally made of metal, and one end (upper end in FIG. 1) of the cylindrical wall 2 as the first electric motor frame is integrally provided with an end wall 3 for closing the end, and the other end of the cylindrical wall 2 ( The lower end (in FIG. 1) is opened, and the fan cover mounting wall 4 is provided so as to integrally project outward from the edge of this opening.
As shown in FIGS. 1 and 4, a bearing mounting portion 5 is integrally formed in the central portion of the end wall 3, and the end wall 3 is located around the mounting portion 5 and has a plurality of cooling members. The through hole 6 is opened.

As shown in FIG. 1, the opening of the cylindrical wall 2 is formed so that its diameter gradually increases toward the fan cover mounting wall 4 side and is continuous with the fan cover mounting wall 4. The fan cover mounting wall 4 is formed by bending an overhanging peripheral portion 4b around the peripheral edge of the overhanging plate portion 4a and bending an overhanging edge portion 4c at the tip of this peripheral portion 4b. The projecting plate portion 4 a is projected outward so as to be orthogonal to the cylindrical wall 2. The overhanging peripheral portion 4b extends substantially parallel to the cylindrical wall 2 in the direction of the end wall 3, and the overhanging edge portion 4c is provided in parallel with the overhanging plate portion 4a.

As shown in FIG. 3, a sheet metal frame end face plate 7 as a second electric motor frame is horizontally mounted on the projecting plate portion 4a. The end face plate 7 has a shape that traverses the opening of the cylindrical wall 2 in the radial direction, and forms an electric motor frame body together with the electric motor frame 1. The frame end face plate 7 is positioned by inserting the bending claws 7a at both ends in the length direction into a plurality of long holes 8 (see FIGS. 3 and 4) provided in the projecting plate portion 4a, and at the same time, these long holes are formed. 8 is attached to the fan cover mounting wall 4 by screwing screws 10 (see FIG. 3) passing through both ends of the frame end face plate 7 in the length direction into a plurality of screw holes 9 provided in the vicinity of There is.

A bearing mounting portion 11 is integrally formed at the center of the frame end face plate 7 in the longitudinal direction. It should be noted that 7b in FIG. 3 may be omitted in the present invention, but in the present embodiment, it is a hole provided for weight reduction and the like. Further, the frame end face plate 7 is inclined so as to gradually separate from the opening of the cylindrical wall 2 from both ends thereof toward the bearing mounting portion 11, but this inclination may be omitted. Further, 12 in FIG. 4 is a screw hole provided in the projecting plate portion 4a, and 13 in FIG. 4 is also a screw hole.

A stator 15 is built in the electric motor frame 1. Therefore, the stator 15 is surrounded by the fan cover mounting wall 4. The stator 15 includes a pair of salient poles 1 of a stator core 16 made of silicon steel plates laminated as shown in FIGS. 1, 3 and 8.
6a (see FIG. 8), the stator windings 17 are attached to each other via insulating slots (not shown).

The stator core 16 has a substantially quadrangular outer diameter shape when viewed from the end face direction, and its four corner outer surfaces are curved surfaces along the inner peripheral surface of the cylindrical wall 2. The stator 15 has its four corner outer surfaces brought into contact with the inner peripheral surface of the cylindrical wall 2, and is press-fitted into the cylindrical wall 2 from its opening side to be housed and fixed.

A pair of closing plates 18 are sandwiched between an end surface of the stator core 16 located on the opening side of the cylindrical wall 2 and the pair of stator windings 17, respectively. These closure plates 1
8 are combined with each other to form a circular outer circumference, and the outer circumference is in contact with the inner peripheral surface of the cylindrical wall 2. As a result, the pair of closing plates 18 close the gap G between the flat outer surface between the corners of the stator core 16 and the inner peripheral surface of the cylindrical wall 2 from the opening side of the cylindrical wall 2.

The construction of the closure plate 18 is shown in FIGS. That is, in the closing plate main portion 61 having the substantially arcuate peripheral end surface 61a along the inner peripheral surface of the cylindrical wall 2, the cooling fan side portion 17a of the stator winding 17 and the rotor 21 described later.
Is formed with a recess 62 for passing through. The first and second parts are provided on both side portions of the closing plate main portion 61 that sandwich the recess 62.
The engaging protrusions 63 and 64 are separately provided integrally with each other, and a slanted tongue 65 is integrally provided on the first engaging protrusion 63 side.

The first engaging projection 63 is formed on one side of the closing plate main portion 61 so as to be slightly raised to form a step.
The second engagement protrusion 64 is formed on the other surface side of the closing plate main portion 61 so as to be slightly raised to form a step. Rectangular engaging holes 66 are formed in the engaging protrusions 63 and 64, respectively. Further, slanting first and second hooking pieces 67 and 68 are respectively cut and raised in opposite directions on the both side portions of the closing plate main portion 61.

In the closing plate 18 having this structure, the first and second engaging protrusions 63, 6 are arranged so that the closing plate main portion 61 overlaps with the end surface of the stator core 16 on the blower fan side from the outside of the stator 15.
4 by inserting the stator core 16
And the cooling fan side portion 17a of the stator winding 17 are sandwiched and attached. Moreover, in this insertion, the pair of closing plates 18 are attached so that the center of the rotor 21 is arranged in point symmetry.

As a result, as shown in FIG. 8, the engaging hole 66 of the first engaging projection 63 of the one closing plate 18 and the second engaging piece 68 of the other closing plate 18 are engaged with each other. With
Hooking hole 66 of the second engaging projection 64 of the one closing plate 18
And the first hooking piece 67 of the other closing plate 18 are engaged with each other, and the slanted tongue pieces 65 of both closing plates 18 overlap one surface of the corresponding closing plate main portion 61, so that both closing plates 18 are Connected to each other.

As shown in FIG. 1, a rotatable rotor 21 passing through the stator 15 is arranged inside the stator 15. Both ends of the rotor shaft 22 of the rotor 21 are separately supported by bearings 23 and 24 respectively incorporated in the bearing mounting portions 5 and 11, and these bearings 23 and 2 are also supported.
Penetrates 4 As shown in FIG. 1, a cooling passage 25 is formed between the outer peripheral surface of the rotor 21 and the inner peripheral surface of the stator core 16 which are opposed to each other. The closing plate 18 does not close the cooling passage 25.

A commutator 26 is attached to the rotor shaft 22. Brush devices 27 are attached to the cylindrical wall 2 at two locations corresponding to the radial direction, respectively, penetrating the cylindrical wall 2.
A brush (not shown) included in these devices 27 is a commutator 26.
The commutator pieces are pressed against the outer peripheral surfaces arranged in the circumferential direction. In addition, a motor frame body composed of the motor frame 1 and the frame end face plate 7, a stator 1
5, the closing plate 18, the rotor 21, the commutator 26, and the brush device 27 constitute an electric motor section of the electric blower.

As shown in FIG. 1, a motor holder 31 made of synthetic resin is attached to the end wall 3 side of the motor frame 1. The holder 31 includes a cylindrical wall cover portion 32 fitted to the outer periphery of the cylindrical wall 2 and having a clearance groove formed of a notch corresponding to the brush device 27 and the like, and the cover portion 3
It is formed of a cylindrical holder portion 33 having a diameter smaller than 2, and a step portion 34 that integrally connects the holder portions 33 and contacts the outer surface of the peripheral portion of the end wall 3.

The holder portion 33 has mounting projections at two locations (not shown) on the inside thereof, and these are provided on screw receiving projections 3a (see FIG. 4) projectingly formed at two locations on the end wall 3. I have come into contact with them. Then, these screw receiving projections 3a
Corresponding to the concave portion 33a provided on the outer surface of the holder portion 33
The electric motor holder 31 is fixed to the electric motor frame 1 by screwing these screws 35 into the screw holes 36 (see FIG. 4) of the screw receiving projection 3a from the mounting screws 35 (see FIG. 2).

One end portion (upper end portion in FIG. 1) of the rotor shaft 22 penetrating the bearing mounting portion 5 and the bearing 23 is located at the inner center of the cylindrical holder portion 33, and the axial flow is at this one end portion. Shaped cooling fan 37 is fixed. In addition,
38 is a nut for fixing the fan. This cooling fan 3
The periphery of 7 is surrounded by the inner peripheral surface of the cylindrical holder portion 33, and the blowing air of the cooling fan 37 is guided by the inner surface of the electric motor holder 31 and guided to the cooling through hole 6.

One sheet metal blower fan 41 is attached via a nut 42 to the other end portion (the lower end portion in FIG. 1) penetrating the bearing mounting portion 11 and the bearing 24 of the rotor shaft 22. The blower fan 41 has a suction port 4 at the center.
1a and a discharge port 41b at the peripheral portion thereof, and discharges the air sucked from the suction port 41a.
It is a centrifugal type which discharges from b in the centrifugal direction.

As shown in FIG. 1, the blower fan 41 is covered with a fan cover 43 made of sheet metal. The fan cover 43 is formed by integrally connecting a cover end wall 43b to a lower end of a cover peripheral wall 43a having a cylindrical shape in FIG. 1, and providing an intake port 44 in a central portion of the wall 43b so as to closely face the intake port 41a. ing. This fan cover 43
Is attached to the fan cover mounting wall 4 by fitting the upper end opening (in FIG. 1) of the cover peripheral wall 43a to the projecting edge 4c of the fan cover mounting wall 4. By this attachment, the inner surface of the cover peripheral wall 43a and the blower fan 4
The first discharge port 41b is opposed to the first discharge port 41b.

Inside the fan cover 43, between the blower fan 41 and the fan cover mounting wall 4, an internal air duct section 4 made of synthetic resin for covering the opening of the electric motor frame 1 is provided.
5 are arranged. This partition 45 is shown in FIGS.
Further, as shown in FIG. 10, an annular partition wall 47 and an outer peripheral wall 48 are integrally provided on the peripheral portion of the disk-shaped base wall 46 facing the blower fan 41, respectively.

The base wall 46 has a diameter larger than that of the blower fan 41, and the central portion thereof is fitted to the outside of the bearing mounting portion 11 of the frame end face plate 7. Note that FIG. 9 and FIG.
The inside 46c is a fitting hole. The base wall 46 has a screw 80 (2 in FIG. 3) screwed into a screw hole 7c (see FIG. 3) provided in the frame end face plate 7 in the vicinity of the bearing mounting portion 11.
It is fixed to the frame end face plate 7 via the dotted chain line).

The annular partition wall 47 is projected in the axial direction of the rotor 21, and the projecting tip end surface is in contact with the surface of the overhanging plate portion 4a of the fan cover mounting wall 4 on the side of the blower fan 41 and is adhesively sealed. In addition, this annular partition 47
A recess 47d (see FIG. 10) that fits into both ends 7d of the frame end face plate 7 in the longitudinal direction is provided at the front end of the frame.

The outer peripheral wall 48 is provided so as to project from the peripheral edge of the internal air duct dividing body 45 toward the fan cover mounting wall 4 side. The periphery of the internal air duct partition body 45 has a blower exhaust unit 4 which will be described later.
It is located outside the fan cover mounting wall 4 in the radial direction. The outer peripheral surface of the outer peripheral wall 48 is the fan cover 43.
The inner peripheral surface of the cover peripheral wall 43a and the inner peripheral surface of the cover peripheral wall 43a face the outer peripheral surface of the annular partition wall 47, respectively. The protruding tip of the outer peripheral wall 48 is the protruding plate portion 4a of the fan cover mounting wall 4.
Is approached to face. Then, for example, the air-blowing distance A between the cover peripheral wall 43a and the outer peripheral wall 48 is 3.3 mm, the protruding length H of the outer peripheral wall 48 is 7.0 mm, the protruding tip of the outer peripheral wall 48 and the protruding plate portion 4a of the fan cover mounting wall 4 are The interval I is set to 5.6 mm.

1 and 9, reference numeral 46a denotes a straightening vane integrally provided on the peripheral portion of the base wall 46 in the direction of the cover end wall 43b so as to contact the inner surface of the cover end wall 43b. As shown in FIG. 9, a plurality of rectifying air passages 46b are formed in an arc shape and surround each other, and a large number of fans are provided so as to surround the blower fan 41. The rectifying air passage 46b is formed so as to gradually increase the air passage cross-sectional area from the inlet on the side of the outlet 41b toward the outlet on the side of the cover peripheral wall 43a, and the wind of the air discharged from the blower fan 41 is formed. A long path is secured to guide the wind while rectifying it. In the present invention, the flow straightening vanes 46a forming the flow straightening air passages 46b may be omitted. Moreover, 46c in FIG. 10 is a rectification rib.

As shown in FIGS. 1 to 4, the protruding plate portion 4a of the fan cover mounting wall 4 is provided with a plurality of first exhaust holes 49 as blower exhaust portions, and
A plurality of second exhaust holes 50 as cooling air exhaust units are provided. Each of the first exhaust holes 49 is formed in a portion located outside the annular partition wall 47 with respect to the projecting plate portion 4a,
Each second exhaust hole 50 is formed in a portion located inside the annular partition wall 47 with respect to the projecting plate portion 4a.

The passage area of the first exhaust hole 49 is equal to that of the second exhaust hole 5.
It is larger than the passage area formed by 0. As shown in FIG. 3, the first exhaust holes 49 and the second exhaust holes 50 are provided on both sides in the width direction of the frame end face plate 7 corresponding to the blower fan side portions 17a of the pair of stator windings 17, respectively. Has been.

In the electric blower FM having the above-mentioned structure, the external air passage partitioning body 75 is attached to the projecting plate portion 4a of the fan cover mounting wall 4. The partition 75 constitutes an electric blower together with the electric blower FM and the air passage partition wall described later, and is shown in FIGS. 1, 2, 11, and 12.
As shown in (1), it is formed in a ring shape from synthetic resin.

The external air duct partition 75 includes an inner peripheral wall 76, an outer peripheral wall 77 parallel to the wall 76, and both the walls 76, 77.
Is formed in a ring shape from a bottom wall 78 that is integrally connected with the above. The inner peripheral wall 76 has the same diameter as the annular partition wall 47 of the internal air duct dividing body 45, and the outer peripheral wall 77 has a diameter larger than the outer diameter of the fan cover 43.

The external air duct partition 75 is attached to the projecting plate portion 4a via screws 79 which are screwed into four screw holes 13 (see FIG. 4) formed in the projecting plate portion 4a of the fan cover mounting wall 4. It is fixed. Inside the annular recess formed by the walls 76 to 78, the portion of the overhanging plate portion 4a located outside the annular partition wall 47, and the fan cover 43.
The opening side portion of the cooling fan 37 side is housed.

Specifically, the inner peripheral wall 76 sandwiches the projecting plate portion 4a between the inner peripheral wall 76 and the annular partition wall 47, and abuts on the surface of the plate portion 4a on the side of the cooling fan 37 and is adhesively sealed so that the air passage partition wall 4 is formed.
It is located on the extension line of 7. The outer peripheral wall 77 is located so as to surround the opening side portion of the cover peripheral wall 43a of the fan cover 43 on the cooling fan 37 side. The bottom wall 78 is located so as to face the outer peripheral side of the first exhaust hole 49 of the fan cover mounting wall 4.

The base wall 46 of the internal air duct dividing body 45
Of air between the outer peripheral surface of the fan cover 43 and the peripheral wall 43a of the fan cover 43, a gap of air between the annular peripheral wall 47 of the internal air duct partitioning body 45 and the peripheral wall 43a, and a first gap as a ventilation gap.
The diameter C of the exhaust hole 49 and the inner peripheral wall 76 of the external air duct partitioning body 75
Between the fan cover mounting wall 4 and the overhanging peripheral portion 4c of the fan cover mounting wall 4, the air blowing gap E between the opening edge of the fan cover 43 and the bottom wall 78 of the external air duct partition 75, and the fan cover 4
The ventilation gap F between the peripheral wall 43a of No. 3 and the outer peripheral wall 77 of the external air duct partitioning body 75 is defined as E <A <F <C <D <B. As a result, the first exhaust air passage 57 (see FIG.
The air blowing path composed of the air blowing gaps A to E leading to the air passages has a passage configuration in which the air blowing path is narrowed and then enlarged.

The electric blower FM having the above-described structure is provided in the main body case of a wet and dry type electric vacuum cleaner as shown in FIG.
As shown in FIG. 3, the cooling fan 37 is built in so that the blower fan 41 is located above and the blower fan 41 is located below. The cooling fan 37 side of the electric blower FM has an annular support rubber 51 fitted to the outside of the holder portion 33 of the electric motor holder 31.
While being supported by the ribs 52 of the main body case via the, the blower fan 41 side of the electric blower FM is fitted to the outside of the corner formed by the cover peripheral wall 43a of the fan cover 43 and the fan cover end wall 43b. Annular support rubber 53
Is supported by the ribs 54a and 54b of the main body case.

Further, reference numeral 55 in FIG. 13 denotes an air duct partition of the main body case, which supports the external air duct partition 71 via an annular support rubber 56. This airway partition 55
The first exhaust passage 57 for blowing air is formed between the air passage and the rib 54a, and the exhaust air passage 57 prevents the air containing water from flowing to the brush device 27 side. Second exhaust passage 5 for cooling air is provided between
8 is formed.

When the electric blower FM having the above structure is operated, the cooling fan 37 and the blower fan 41 are rotated together with the rotor 21. Therefore, due to the rotation of the cooling fan 37, the wind sent in the axial direction of the cooling fan 37 will not be discharged.
Through the cooling through hole 6 and flows into the electric motor frame 1 so as to be blown to the cooling fan side portion 17b of the stator winding 17. This wind has a configuration in which a closing plate 18 that closes a gap G between the stator 15 and the electric motor frame 1 is attached to the cooling passage 2 between the stator 15 and the rotor 21.
5, the stator 15 and the rotor 21 are cooled.

The wind that has passed through the cooling passage 25 is guided to the inner surface of the internal air passage compartment 45, passes through the second exhaust holes 50 formed in the projecting plate portion 4a of the fan cover mounting wall 5, and passes through the motor frame 1 It is discharged outside. Moreover, in the guide of the cooling air in the internal air passage partition body 45, the cooling passage 25 is located between the pair of stator windings 17, and
The exhaust hole 50 is the portion 17 of the stator winding 17 on the blower fan side.
Since the cooling air passing through the cooling passage 25 is provided at the outer position so as to be sandwiched between the cooling passage 25 and the cooling passage 25, the internal air passage partition body 45 is arranged so as to be along the blower fan side portion 17a.
The second exhaust hole 50 is reached while being guided by. The flow of the cooling air caused as described above is shown by a dotted arrow in FIG.

Therefore, this cooling air can reduce the temperature rise of the electric motor section. That is, as described above, not only the cooling air is blown to the blower fan side portion 17b of the stator winding 17 and then the cooling air is concentratedly passed through the cooling air passage 25, but also the blower fan side portion 17a of the stator winding 17 is provided. Since the cooling air can be made to flow along the
5 and the rotor 21 can be effectively air-cooled to reduce the temperature rise of the electric motor section.

The cooling air discharged to the outside of the electric motor frame 1 through the second exhaust holes 50 passes between the outer peripheral surface of the cylindrical wall 2 of the electric motor frame 1 and the inner peripheral surface of the external air duct partition 75. It is guided to the second exhaust air passage 58 through which the air is appropriately exhausted to the outside of the main body case.

On the other hand, the rotation of the blower fan 41 forms the flow of blown air shown by the solid line in FIG. That is, the air sucked into the blower fan 41 through the intake port 44 of the fan cover 43 and the suction port 41a of the blower fan 41 is discharged from the discharge port 41b of the fan 41 in the centrifugal direction.

After passing through the rectifying air passage 46b, the discharged very high-speed air hits the inner surface of the cover peripheral wall 43a of the fan cover 43, changes its direction to the fan cover mounting wall 4 side, and flows, while flowing in the inner air passage. Outer peripheral wall 4 of partition 45
8 and the cover peripheral wall 43a of the fan cover 43 and pass between them. After this, the direction is changed to the outer peripheral wall 48.
Of the protruding end of the fan and the protruding plate portion 4 of the fan cover mounting wall 4
The first exhaust gas that flows into the space between the annular partition wall 47 and the outer peripheral wall 48 of the internal air duct partitioning body 45 through the gap between the first exhaust gas and the fan cover mounting wall 4 formed on the projecting plate portion 4a. It is discharged to the outside of the motor frame 1 through the hole 49 along the axial direction of the rotor 21.

In this air blowing operation, the internal air duct division body 4
The annular partition wall 47 of 5 divides the air passage so that the cooling air and the blown air do not mix in the fan cover 43, and the respective winds are directed toward the corresponding exhaust holes 49, 50 to the shaft of the rotor 21. I will guide you in the direction. Therefore, it is possible to prevent a smooth flow of cooling air from being impaired and impair the air-cooling action of the electric motor unit, and it is also possible to prevent disturbance of the air flow,
A good air-blowing action can be maintained.

The blown air discharged to the outside of the electric motor frame 1 through the first exhaust hole 49 is formed between the inner peripheral surface of the projecting peripheral portion 4b of the fan cover mounting wall 4 and the outer peripheral surface of the external air duct partitioning body 75. It is guided to the first exhaust air passage 57 through the space and is appropriately exhausted from the air passage 57 to the outside of the main body case.

As described above, the cooling air and the blown air discharged from the exhaust holes 49 and 50 are separately guided by the external air passage partitioning body 75 and the air passage partition wall 55, so that these air streams are mixed. And the first and second exhaust air passages 5
Since the cooling air and the blast are separately guided and exhausted by 7, 58, even if the air sucked into the blast fan 41 contains water, the electric blower FM may be exposed to the water from the outside. Absent. Further, in the air blowing operation, the air blown by the rotation of the air blower fan 41 has a higher pressure than the cooling air, but the internal air passage partitioning body 45 prevents the air blown from being sent into the electric motor section of the electric blower FM. It can be prevented. Therefore, even if the air sucked by the blower fan 41 contains water, the inside of the electric motor unit is not exposed to this water. Since the water contained in the blown air does not act on the inside and outside of the electric motor unit in this manner, it is possible to prevent adverse effects of water such as rusting the iron-based parts of the electric motor unit.

Further, according to the blowing operation, the high-speed air is not exhausted directly through the cover peripheral wall 43a of the fan cover 43, and the wind is diverted by the cover peripheral wall 43a. Thus, by providing the first exhaust hole 49 in the projecting plate portion 4a of the fan cover mounting wall 4, it is possible to increase the physical air passage distance from the discharge port 43a to the first exhaust hole 49. In addition, the internal air duct partition 45
The outer peripheral wall 48 prevents the wind from flowing as shown by the dotted arrow a in FIG. 1, guides the wind as shown by the solid arrow b, and changes the direction of the wind so that the wind flows in the actual wind path. The length can be made longer.

In this way, the discharge port 41 of the blower fan 41
Immediately after being discharged from b, the force of the high-speed high-speed wind can be killed and discharged from the first exhaust hole 49 in the axial direction of the rotor 21, so that it occurs when the wind passes through the first exhaust hole 49. Wind noise can be reduced. Therefore, it is not necessary to bend the edge of the first exhaust hole 49 to reduce wind noise.

If a quieter operation is required, it is effective to bend the edge of the first exhaust hole 49 to reduce wind noise. Moreover, since the projecting plate portion 4a provided with the first exhaust holes 49 is not a curved surface but a flat surface, it is possible to easily perform the boring process of the first exhaust holes 49 provided therein.

Moreover, in the present embodiment, due to the structure of the external air duct partitioning body 75, the air blown out from the first exhaust holes 49 is supplied to the bottom wall 78 and the outer peripheral wall 7 of the external air duct partitioning wall 75.
Since the air is guided to the first exhaust air passage 56 while changing the direction by 7 and making a U-turn, it is possible to further weaken the force of the air blowing and further reduce the wind noise caused by the air blowing operation. At this time, since the air blown from the air blower fan 41 to the first exhaust air passage 57 repeats expansion and contraction a large number of times due to the configuration of the air blow gaps A to F as described above, the wind noise is further reduced by the sound deadening effect. The sound can be made quieter.

The reduction of the driving noise as described above was clarified in the following noise measurement test. In this measurement test, the electric blower was installed as a single unit on a urethane resin measuring table having a thickness of 60 mm and about 21 Kg / m3, and the intake port 44 of the fan cover 43 was kept open,
The measurement result is shown in FIG. 14, which was carried out with the microphone placed 1 m away from the surface of the electric blower. Note that FIG. 15 shows the outer peripheral wall 4 having a protrusion length H of 10 mm.
8 is a measurement result of an electric blower using the internal air duct partitioning body 45 including 8 and FIG. 16 is a measurement result of an electric blower using the internal air duct partitioning body 45 not including the outer peripheral wall 48.

The noise level of the electric blower of this embodiment shown in FIG. 14 is 85.4 dB.
Noise level of the electric blower shown in FIG. 16 with no configuration
It was found that the noise level can be reduced by 1.4 dB compared to 86.8 dB. As can be seen from the comparison between FIG. 14 and FIG. 16, in the present embodiment, the frequency characteristic of the L portion in FIG. 16 can be improved, and thereby the noise level can be reduced. Further, even if the protrusion length H has the outer peripheral wall 48 of 10 mm, the noise level is 85.6 dB as shown in FIG.
It turns out that it can be made smaller.

As described above, the wind formed by the blower fan 41 is directed to the fan cover mounting wall 4 in the axial direction of the rotor 21.
The support rubber 53 fitted to the outer side of the fan cover 43 does not block the first exhaust hole 49 because it is discharged from the above. Therefore, the fitting depth K (see FIG. 13) of the support rubber 53 with respect to the fan cover 43 can be secured deep, and the mounting state of the rubber 53 can be stabilized.

Therefore, when the electric blower FM is assembled in the main body case of the electric vacuum cleaner, the support rubber 53 does not drop accidentally and the assembling work can be facilitated. Nevertheless, there is no need to provide fan fans in multiple stages to lengthen the fan cover 43 in order to increase the fitting depth of the support rubber 53.
Since only one is required, the axial length of the electric blower FM can be shortened.

Further, according to the flow of the air formed by the blower fan 41, there is no need to provide a space around the fan cover 43 for the air to flow. Therefore, electric blower FM
This blower FM can reduce the substantial installation space of
It is advantageous when the other parts around the are arranged close to each other, or when the main body case of the electric vacuum cleaner is downsized along the radial direction of the electric blower FM.

FIG. 17 shows a second embodiment of the present invention. In the description of this embodiment, the same components as those in the first embodiment will be designated by the same reference numerals as those in the first embodiment, and the description thereof will be omitted. Only the components different from the first embodiment will be described below. To do.

The second embodiment differs from the first embodiment in the configuration of the outer peripheral wall 48a of the internal air duct dividing body 45,
The rest of the configuration is the same as that of the first embodiment including parts not shown. That is, the outer peripheral wall 48a whose protruding tip is brought closer to the projecting plate portion 4a of the fan cover mounting wall 4 is gradually inclined closer to the cover peripheral wall 43a of the fan cover 43 as it goes toward the protruding tip direction.

In the structure of the second embodiment, in addition to achieving the intended object of the present invention by the same operation as that of the first embodiment, noise reduction can be further promoted. That is, the rectifying air passage 4 discharged from the blower fan 41
The air flowing toward the first exhaust portion 49 through 6b is guided obliquely outward between the cover peripheral wall 43a of the fan cover 43 and the outer peripheral wall 48a of the internal air passage partitioning body 45, and the flow of the wind is Since it is possible to reduce abrupt changes such as bending at a right angle, it is possible to reduce the occurrence of turbulence. Therefore, the generation of sound due to turbulence is suppressed, and the overall noise level can be lowered. Moreover, since the generation of turbulence is suppressed as described above, the energy loss of the wind is reduced and the wind easily flows, so that the motor efficiency can be improved.

FIG. 18 shows a third embodiment of the present invention. In the description of this embodiment, the same components as those in the first embodiment will be designated by the same reference numerals as those in the first embodiment, and the description thereof will be omitted. Only the components different from the first embodiment will be described below. To do.

The third embodiment differs from the first embodiment in the structure of the outer peripheral wall 48a of the internal air duct partitioning body 45 and the cover peripheral wall 43c of the fan cover 43, and other structures are not shown. The structure is the same as that of the first embodiment including the part.

That is, the outer peripheral wall 48a whose protruding tip is brought closer to the protruding plate portion 4a of the fan cover mounting wall 4 is inclined toward the cover peripheral wall 43c side of the fan cover 43 in the direction of the protruding tip. There is. The portion of the cover peripheral wall 43c that faces the outer peripheral wall 48a is inclined parallel to the outer peripheral wall 48a.

Also in the structure of the third embodiment, the intended object of the present invention can be achieved by the same operation as that of the first embodiment, and the noise reduction can be further promoted. The reason for this is the same as in the second embodiment, so a description thereof will be omitted.

The present invention is not limited to the above embodiments. For example, one end of the stator core is connected to a first electric motor frame forming a fan cover mounting wall, and the other end of the stator core is connected to a second electric motor frame to which a brush device is attached. The present invention can also be applied to an electric blower having a configuration in which the is exposed. When providing a closing plate for this type of implementation, the closing plate may be attached to the stator so as to close the gap between the second motor frame and the stator.

Further, in the present invention, the ventilation exhaust unit 49 is
It may be formed by an elongated hole extending in the circumferential direction of the projecting plate portion 4a. Further, in each of the above-mentioned embodiments, the blower exhaust part 49 and the cooling exhaust part 50 are formed by separate exhaust holes, respectively.
Instead of this, a hole which is divided into two by the annular partition 47 is provided in the projecting plate portion 4a, and the hole portion of the hole located outside the annular partition 47 is used as the blower exhaust part 49, and the annular partition is provided. You may use the hole part located inside 47 as the cooling exhaust part 50.

Moreover, the closing plate 18 may be omitted in the present invention. That is, since the blower fan side portion 17a of the stator winding 17 is bent outward in the radial direction so as to be away from the rotor shaft 21, and a part thereof has a relationship facing the gap G when the closing plate 18 is not provided, Along with the cooling air that passes through the cooling passage 25 and reaches the cooling exhaust portion 50, the gap G
This is because the blower fan side portion 17a can be air-cooled even with the cooling air that passes through to the cooling exhaust portion 50.

Further, in each of the above-mentioned embodiments, the external air duct partitioning body 75 is attached to the electric blower, but these are provided on a blower setting member such as the main body case of the electric vacuum cleaner, and the electric blower is installed on this member. Alternatively, it may be carried out by hitting the surface of the fan mounting wall of the electric blower on the cooling fan side.

[0074]

As described in detail above, according to the electric blower of the present invention, the force of the high-speed wind discharged from the blower fan is killed, and the blower exhaust portion of the fan cover mounting wall is arranged along the axial direction of the rotor. In addition, the outer peripheral wall of the inner air passage partition can ensure a long air passage length from the air blower fan to the air blower exhaust unit, so that the wind noise accompanying the air blow operation can be reduced and the air blower exhaust unit covers the fan. Since it is not blocked by the support rubber fitted to the outside of the fan and it is not necessary to provide blowers in multiple stages, the axial dimension of the entire electric blower can be shortened.

[Brief description of drawings]

FIG. 1 is a side view showing a partial cross-section of the configuration of an electric blower according to a first embodiment of the present invention.

FIG. 2 is a diagram showing the configuration of the electric blower according to the first embodiment as viewed from the direction of arrow Y in FIG.

FIG. 3 is a diagram showing a configuration of an electric motor unit of the electric blower according to the first embodiment as viewed from a direction of an arrow X in FIG. 1.

FIG. 4 is a diagram showing a configuration of an electric motor frame of the electric blower according to the first embodiment as viewed from a direction of an arrow X in FIG. 1.

FIG. 5 is a plan view showing the configuration of the closing plate according to the first embodiment.

6 is a side view of the closing plate shown in FIG.

FIG. 7 is a cross-sectional view of the closing plate taken along line WW in FIG.

8 is a plan view showing a state in which the pair of closing plates shown in FIG. 5 are attached to a stator.

FIG. 9 is a diagram showing the internal air passage compartment according to the first embodiment as viewed from the direction of arrow X in FIG.

FIG. 10 is a view showing the internal air duct partitioning body according to the first embodiment as viewed from the direction of the arrow Y in FIG.

FIG. 11 is a plan view showing a configuration of an external air duct partitioning body according to the first embodiment.

FIG. 12 is a side view showing a partial cross section of the external air duct partitioning body shown in FIG. 11.

FIG. 13 is a view showing a mounting state of the electric blower according to the first embodiment.

FIG. 14 is a diagram showing a result of noise measurement of the electric blower according to the first embodiment.

FIG. 15 is a first part of the electric blower according to the first embodiment.
The figure which shows the result of the noise measurement about the electric blower which concerns on a comparative example.

FIG. 16 is a second part of the electric blower according to the first embodiment.
The figure which shows the result of the noise measurement about the electric blower which concerns on a comparative example.

FIG. 17 is a side view showing a partial cross section of the configuration of the electric blower according to the second embodiment of the present invention.

FIG. 18 is a side view showing a partial cross section of the configuration of the electric blower according to the third embodiment of the present invention.

[Explanation of symbols]

4 ... Fan cover mounting wall, 4a ... Overhanging plate part, 6 ...
Cooling through hole, 15 ... Stator, 21 ... Rotor, 22 ... Rotor shaft, 25 ... Cooling passage, 37 ... Cooling fan, 41 ... Blower fan, 43 ... Fan cover, 43a, 43c ... Cover peripheral wall, 45 ... Internal air passage Partition, 46 ... Base, 47
... annular partition wall, 48, 48a ... Outer peripheral wall, 49 ... First exhaust hole (blast exhaust section), 50 ... Second exhaust hole (cooling exhaust section).

Claims (1)

[Claims] 1. A centrifugal fan is attached to one end of a rotor shaft of a rotor arranged inside a stator, and a cooling fan for cooling the stator and the rotor to the other end of the rotor shaft. In the electric blower, a fan cover mounting wall that surrounds the stator and extends outward is provided on the side of the blower fan, and a fan cover that covers the blower fan is mounted on the mounting wall. An internal air passage partition having an annular partition wall that abuts the surface of the wall on the side of the blower fan is arranged between the fan cover mounting wall and the blower fan, and discharges from the blower fan to the fan cover mounting wall. A blower / exhaust part for discharging the generated wind in the axial direction of the rotor shaft is provided outside the annular partition wall, and is provided in front of the blower / exhaust part. An outer peripheral wall facing the inner peripheral surface of the fan cover is provided on the peripheral edge of the internal air passage partitioning body located radially outside of the fan cover mounting wall so as to project toward the fan cover mounting wall. Electric blower.