JP6382122B2 - Electric blower and vacuum cleaner equipped with the same - Google Patents

Description

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

  As an electric blower for a conventional vacuum cleaner, there is one using a DC brushless motor for miniaturization, for example, one disclosed in JP 2010-196707 A (Patent Document 1).

  In the rotor assembly constituting the electric blower disclosed in JP 2010-196707, a rotor core (magnet) is attached to one end of the shaft, and an impeller is attached to the other end of the shaft. . A bearing cartridge is attached to the shaft between the rotor core and the impeller. The bearing cartridge includes a pair of bearings press-fitted into the shaft, a preload spring disposed between the bearings, and a sleeve surrounding the pair of bearings, and the sleeve has a thermal expansion coefficient substantially matching the shaft. ing.

  As another conventional technique, for example, there is one disclosed in Japanese Patent Laid-Open No. 2014-219006 (Patent Document 2).

  The compressor disclosed in Japanese Patent Application Laid-Open No. 2014-219006 includes a frame, a rotor assembly, and a seat sink assembly. The rotor assembly has an impeller, a bearing assembly, and a rotor core (magnet) fixed to a shaft. The bearing assembly includes a pair of bearings. The heat sink assembly includes a sleeve having a heat sink, and a heat sink having a plurality of legs extending in a radial direction is installed on an end side of the sleeve. The sleeve is fixed to the bearing, and the heat sink is fixed to the frame.

JP 2010-196707 JP 2014-219006

  In the rotor assembly of Patent Document 1, the sleeve of the bearing cartridge is fixed to the housing of the electric blower. Since the sleeve and the housing are separately manufactured and fixed, the accuracy of the coaxiality may be reduced due to the dimensional accuracy of the sleeve and the housing. As a result, the center axis of the stator core and the rotor core attached to the housing do not coincide with each other, and there is a risk that motor efficiency is reduced, vibration, and noise are generated.

  Further, although the cylindrical sleeve functions as a heat sink, the cylindrical sleeve has a small surface area and insufficient cooling of the bearing, which may impair the reliability of the bearing.

  In the technique described in Patent Document 2, a heat sink having a plurality of legs extending in the radial direction is provided on the end side of the sleeve, and the heat sink is fixed to the frame. was there.

  The object of the present invention is to solve the above-mentioned problems, to reduce the weight of the electric blower, to cool the bearing efficiently, and to improve the motor efficiency, that is, to improve the electric blower efficiency and to reduce vibration and noise. It is providing the electric blower and vacuum cleaner which can aim at.

  Furthermore, when a brushless motor driven by a low-voltage battery is used, the efficiency of the electric blower improves, so that the electric blower input can be lowered to obtain the same output, and a vacuum cleaner with a longer operation time can be obtained. It is to provide.

  In order to solve the above problems, one of the representative electric blowers of the present invention includes a rotating shaft provided rotatably, a rotor core integrally formed at one end of the rotating shaft, and the rotating shaft. A centrifugal impeller attached to an end; a bearing to which the rotary shaft is attached between the rotor core and the centrifugal impeller; a bearing cover containing the bearing; and the bearing cover integrally formed A resin housing, a diffuser blade, a guide blade having a return guide blade on the back surface of the diffuser blade, a fan casing containing the centrifugal impeller and the guide blade, and on the outer periphery of the bearing cover Is provided with a reference surface on which the heat sink is not provided on the side surface of the bearing cover, and the reference surface is an interface between the bearing cover and the resin housing. It is accomplished by a reference at the time of inner diameter cutting to a fixed reference plane during insert molding and the outer ring of the bearing.

  According to the present invention, the electric blower can be reduced in weight compared to the conventional one, and the heat generated in the bearing can be effectively radiated by the heat sink provided in the bearing cover, which is highly reliable and highly efficient. An electric blower and a vacuum cleaner provided with the same can be provided.

  Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

The external view of the electric blower in one Example of this invention. The longitudinal cross-sectional view of an electric blower. (A) is a perspective view of the centrifugal impeller in one Example of this invention, (b) is a longitudinal cross-sectional view of a centrifugal impeller. BRIEF DESCRIPTION OF THE DRAWINGS It is an external view of the shroud board which comprises the centrifugal impeller in one Example of this invention, (a) is a perspective view, (b) is a side view, (c) is a rear view. It is a perspective view of the hub board which has the blade | wing which comprises the centrifugal impeller in one Example of this invention. (A) is a perspective view of one Example of the guide blade in this invention, (b) is a rear view of a guide blade, (c) is a longitudinal cross-sectional view of a guide blade. It is explanatory drawing which shows the flow in the diffuser in one Example of this invention. (A) is a perspective view of one Example of the fan casing in this invention, (b) is a longitudinal cross-sectional view of a fan casing. (A) is the perspective view which integrated the housing and bearing cover in one Example of this invention, (b) is the rear view which integrated the housing and bearing cover. It is sectional drawing in the AA line of the electric blower of Fig.1 (a). (A) is sectional drawing in the BB line of Fig.8 (a), (b) is sectional drawing in the CC line of Fig.8 (a). It is a perspective view of the bearing cover in one Example of this invention. 1 is a perspective view of a vacuum cleaner to which an electric blower according to an embodiment of the present invention is applied. It is sectional drawing which showed typically the cleaner body in the vacuum cleaner of FIG.

  An embodiment of the present invention will be described below with reference to the drawings.

  A vacuum cleaner 300 according to an embodiment of the present invention will be described with reference to FIGS. 12 and 13. FIG. 12 shows a perspective view of a vacuum cleaner to which the electric blower of the present embodiment is applied.

  As shown in FIG. 12, reference numeral 100 denotes a dust collecting chamber 101 for collecting dust and a vacuum cleaner main body that houses an electric blower 200 (FIG. 13) that generates a suction airflow necessary for collecting dust, and 102 denotes a vacuum cleaner main body. A holding part to which 100 is attached, 103 is a grip part provided at one end of the holding part 102, and 104 is a switch part for turning on and off the electric blower 200 provided in the grip part. A suction body 105 is attached to the other end of the holding part 102, and the cleaner body 100 and the suction body 105 are connected by a connection part 106. Reference numeral 107 denotes a charging stand for charging the battery unit 108 (FIG. 13).

  In the above configuration, when the switch unit 104 of the grip unit 103 is operated, the electric blower 200 housed in the cleaner body 100 is operated to generate a suction airflow. Then, dust is sucked from the suction body 105 and collected in the dust collecting chamber 101 of the cleaner body 100 through the connecting portion 106.

  Next, the cleaner body 100 will be described using a cross-sectional view schematically showing the cleaner body 100 in the electric vacuum cleaner shown in FIG.

An electric blower 200 that generates suction force, a battery unit 108 that drives the electric blower 200, a drive circuit 109, and a dust collection chamber 101 are disposed inside the cleaner body 100.
The vacuum cleaner main body 100 can be removed from the holding portion 102 and used as a handy vacuum cleaner. The vacuum cleaner main body 100 is provided with a main body blip portion 110 and a mouth opening 111. 112 (FIG. 12) is a main body switch unit for turning on and off the electric blower 200 when used as a handy cleaner. The main body switch 112 can be operated even when the cleaner main body 100 is attached to the holding unit 102.

  Next, the electric blower 200 will be described with reference to an external view of the electric blower shown in FIG. 1A and a longitudinal sectional view of the electric blower shown in FIG. The electric blower 200 is roughly divided into a blower unit 201 and an electric motor unit 202. The blower unit 201 includes a centrifugal impeller 203, a fan casing 204 that houses the centrifugal impeller 203, a diffuser 205a including a plurality of diffuser blades 13, and a plurality of return guide blades 14 on the back surface of the diffuser 205a. The guide vane 205 is provided with a return guide 205b. The fan casing 204 is provided with an air suction port 206. The centrifugal impeller 203 is made of a thermoplastic resin and is directly connected to the rotating shaft 207.

  In this embodiment, the centrifugal impeller 203 is press-fitted and fixed to the rotary shaft 207. However, a screw may be provided at the end of the rotary shaft 207 and the centrifugal impeller 203 may be fixed using a fixing nut.

  The electric motor unit 202 includes a rotor core 209 fixed to a rotating shaft 207 housed in a housing 208 and a stator core 210 fixed to the housing 208. A conductive wire 211 is wound around the stator core 210 to form a phase winding together. The phase winding is electrically connected to a circuit unit (not shown) provided in the electric blower 200.

  The rotor core 209 is formed at the end of the rotating shaft 207 opposite to the end to which the centrifugal impeller 203 is fixed, and is made of a rare earth bond magnet. A rare earth bond magnet is made by mixing a rare earth magnetic powder and an organic binder. As the rare earth bond magnet, for example, a samarium iron nitrogen magnet, a neodymium magnet, or the like can be used. The rotor core 209 is integrally formed with the rotating shaft 207.

  In the present embodiment, a permanent magnet is used for the rotor core 209. However, the reluctance motor, which is a kind of a non-commutator electric motor capable of high-speed rotation of 80,000 rotations per minute or the like, is not limited thereto. May be used.

  A bearing 212 is provided between the centrifugal impeller 203 and the rotor core 209, and the rotary shaft 207 is rotatably supported. A ring 213 for balance adjustment is attached to the end of the rotating shaft 207 on the rotor core 209 side and closer to the end than the rotor core 209. The two-surface balance can be corrected by rotating the rotating body and scraping the back surface of the centrifugal impeller 203 and the ring 213. The balance adjusting ring 213 is a metal material having a specific gravity greater than that of the rotor core 209, and is manufactured by, for example, a sintered product such as a copper material or machining.

  A positioning sleeve 214 for the bearing 212 is disposed between the bearing 212 on the rotor core 209 side and the rotor core 209.

  The housing 208 is made of synthetic resin and has a support portion 26 that fixes a bearing cover 215 that encloses the bearing 212. A bearing 212, a sleeve 216, and a spring 217 are provided in the bearing cover 215. The springs 217 are arranged in a compressed state and abut against the outer rings of the bearings 212 to apply preload.

  On the outer periphery of the bearing cover 215, a plurality of cooling fins 27 that are long in the direction of the rotation axis, which is a heat sink for cooling the bearing 212, are provided. The bearing cover 215 is made of a nonmagnetic metal material and is integrated with the resin housing 208 by insert molding.

  A screw hole 28 extending in the rotation axis direction is formed at the end of the support portion 26 of the resin housing 208. A fixing screw 218 can be screwed into the screw hole 28, and the guide blade 205 is fixedly installed on the resin housing 208 by screwing the fixing screw 218.

  The housing 208 is provided with an opening 34 so that air flows into the housing 208 and an exhaust port 35 for discharging air to the outside of the electric blower 200.

  The stator core 210 disposed at the end of the housing 208 is fixed to the housing 208 by a fixing screw 219.

  Next, the flow of air in the electric blower 200 will be described. When the motor section 202 is driven to rotate the centrifugal impeller 203, air flows from the air suction port 206 of the fan casing 204 and flows into the centrifugal impeller 203. The air that has flowed in is boosted and accelerated in the centrifugal impeller 203 and is discharged from the centrifugal impeller 203. The air flow discharged from the centrifugal impeller 203 is guided to the guide blade 205.

  The diffuser 205a of the guide vane 205 is provided with a plurality of diffuser blades 13 (FIG. 5), and the air flow is decelerated between the vanes of the diffuser blade 13 so that the kinetic energy of the air flow is converted into pressure energy and the pressure is increased. To rise. The airflow discharged from the diffuser 205a flows into the return guide 205b from the flow path 18 (FIG. 6) formed between the inner surface of the fan casing 204 and the rear edge of the diffuser 205a. In addition, although the diffuser with a blade | wing is used in a present Example, it is good also as a diffuser without a blade | wing. In that case, a plurality of support columns are provided on the outer diameter side of the guide vanes to support the fan casing 204.

  The air flow that has passed through the return guide blade 14 of the return guide 205 b flows into the housing 208 through the opening 34 of the housing 208, the cooling fins 27 of the bearing cover 215 are cooled, and the bearing 212 is cooled via the bearing cover 215. The Further, the rotor core 209, the stator core 210, and the conducting wire 211 are cooled and discharged to the outside. Thereby, each part in the housing 208 is cooled. A part of the air flow that has passed through the return guide blade 14 is discharged to the outside from the exhaust port 35 of the housing 208.

  A blower unit 201 according to an embodiment of the present invention will be described with reference to FIGS. 2A is a perspective view of an embodiment of a centrifugal impeller according to the present invention, FIG. 2B is a sectional view of the centrifugal impeller, FIG. 3 is an external view of a shroud plate constituting the centrifugal impeller, and FIG. FIG. 5A is a perspective view of a guide blade according to the present invention, FIG. 5B is a rear view, FIG. 5C is a cross-sectional view, and FIG. FIG. 7A is a perspective view of a fan casing according to the present invention, and FIG. 7B is a cross-sectional view thereof.

  First, a centrifugal impeller 203 according to an embodiment of the present invention will be described with reference to FIGS. A centrifugal impeller 203 according to an embodiment of the present invention includes a shroud plate 1, a hub plate 2, and a plurality of blades 3. The hub plate 2 and the blade 3 are integrally formed of a thermoplastic resin.

  The shroud plate 1 made of a thermoplastic resin is formed with an annular suction opening 4 for sucking air at the center. The suction opening 4 is provided with a straight portion 5 substantially parallel to the rotation shaft 207, and the tip is thin. The shroud plate 1 is provided with a curved surface portion 6 for turning the axial flow flowing from the suction opening 4 into a radial flow, the straight portion 5 and the curved surface portion 6 are smoothly connected, and the radial direction from the curved surface portion 6 to the outer diameter is provided. It is formed to face.

  On the flow path surface of the shroud plate 1, a concave groove 7 is formed at a position corresponding to the blade 3 from the curved surface portion 6 to the outer diameter, and extends to the outer diameter side. The concave groove 7 is provided with a through hole 8.

  At the center of the hub plate 2 is formed a convex boss 9 into which the rotary shaft 207 is inserted and fixed. The blades 3 formed integrally with the hub plate 2 are installed at equal intervals in the circumferential direction, and have a blade shape that retreats in the rotation direction from the inner diameter side toward the outer diameter direction. The boss 9 is formed with a curved surface 9a so as to extend from the axial direction to the radial direction.

  A convex portion 2 a is provided on the outer periphery of the rear surface side of the blade 3 of the hub plate 2. The two-surface balance can be corrected by rotating the rotating body and scraping off the balance adjusting ring 213 attached to the projection 2a and the shaft end of the rotating shaft 207. Thereby, the unbalance amount of the rotating body including the centrifugal impeller 203 can be reduced, vibration and noise can be reduced, and high-speed rotation of 80,000 rotations per minute or more can be achieved.

  Protruding claws 10 are formed on the upper surface of the blade 3. A welding rib 11 is formed on the upper surface of the blade 3 on the outer diameter side from the claw 10. An inclined surface 12 is formed on the pressure surface (convex surface) side of the blade 3 so that the upper surface of the blade 3 on the inner diameter side from the claw 10 of the blade 3 is in close contact with the curved surface portion 6 of the shroud plate 1. The shape of the welding rib 11 may be a triangle, a semicircle, or a trapezoid.

  Centrifugal impeller by engaging the projection 3 of the blade 3 and the through hole 8 of the shroud plate 1 and the concave groove 7 of the shroud plate 1 and the blade 3 and joining the claw 10 and the welding rib 11 by welding. 203 is formed. The curved surface portion 6 of the shroud plate 1 and the inclined surface 12 of the blade 3 are not welded.

  In the present embodiment, since the curved surface portion 6 of the shroud plate 1 and the inclined surface 12 of the blade 3 are not welded, the welding processing from the curved surface portion 6 of the shroud plate 1 to the outer diameter from the substantially axial direction. Can only be done.

  The welding rib 11 melts in the concave groove 7, but the volume of the welding rib 11 is made smaller than the volume of the gap when the blade 3 is inserted into the concave groove 7. Therefore, it can suppress that the melted resin material protrudes in the centrifugal fan flow path.

  Moreover, since the welding rib 11 of the blade 3 is melted and welded to the shroud plate 1 in the flow channel where the pressure from the vicinity of the channel to the outlet becomes high, leakage between the blades 3 can be prevented. it can.

  In addition, an inclined surface 12 is formed on the front edge side of the blade 3, which is the front edge side of the centrifugal impeller 203, so as to coincide with the shape of the curved surface portion 6 of the shroud plate 1. In the centrifugal impeller 203, the inlet flow is particularly important, and the curved surface portion 6 of the shroud plate 1 is not welded, so that no burr or the like due to welding occurs on the inclined surface 12 portion of the blade 3. That is, the air can be smoothly introduced into the blade 3 without disturbing the flow on the inlet side.

Further, the suction opening 4 of the shroud plate 1 is formed, the straight portion 5 is provided, and the curved surface portion 6 is smoothly formed. Is formed. Therefore, the axial flow flowing in from the suction opening 4 can be smoothly turned into the radial flow, can flow into the blade 3, and the bending loss at the inlet can be reduced.
During operation, the front edge side works so that the curved surface portion 6 of the shroud plate 1 and the inclined portion 12 of the blade 3 are in close contact with each other, so there is no gap between the blade 3 and the shroud plate 1 on the inlet side. Efficiency can be improved.

  Although the centrifugal impeller 203 is made of a thermoplastic resin, an engineering plastic material having a heat resistance of 100 ° C. or higher and a tensile strength of 100 MPa or higher is preferred in order to withstand centrifugal stress in order to prevent deformation caused by heat generated by an electric motor or the like. . For example, it is more desirable that the polyether ether ketone (PEEK) or PEEK contains carbon fibers. Accordingly, the resin centrifugal impeller 203 can be realized that is lighter than the metal centrifugal impeller, can secure strength, and can withstand high-speed rotation.

  Next, a guide blade 205 according to an embodiment of the present invention will be described with reference to FIGS. The guide vane 205 of one embodiment according to the present invention is made of resin, and includes a plurality of diffuser vanes 13, a plurality of return guide vanes 14 formed on the downstream side of the diffuser vanes 13, a diffuser vane 13 and a return. A partition plate 15 that partitions the guide blade 14 is integrally formed.

  A rib 13a is formed on the upper surface of the diffuser blade 13 and is in contact with the inner surface (25 in FIG. 7) of the fan casing 204. In the diffuser 205 a, a diffuser flow path is formed by the fan casing 204, the diffuser blade 13, and the partition plate 15, and in the return guide 205 b, a return guide flow path is formed by the partition plate 15 and the return guide blade 14. The outer diameter side of the diffuser blade 13 is gently inclined in the axial direction to form a diffuser channel inclined in the axial direction.

  The partition plate 15 is provided with a through hole 16 for fixing the guide vane 205 to the resin housing 208. A fixing screw 218 is inserted into the through hole 16, and the guide blade 205 is fixed to the housing 208 by the screw hole 28 and the fixing screw 218 of the housing 208.

  A cylindrical convex portion 17 is provided on the outer periphery of the through hole 16 on the return guide 205b side. By fitting the convex portion 17 and the concave portion 29 (FIG. 10) of the housing 208, leakage to the blower portion 201 side is prevented.

  As shown in FIG. 6, a substantially triangular flow path 18 is formed on the outer peripheral end side of the diffuser blade 13 so that the air flowing out from the diffuser blade 13 flows to the return guide blade 14 side. The incoming flow 19 to the diffuser blade 13 is decelerated in a flow passage surrounded by the adjacent diffuser blade 13, the partition plate 15 and the fan casing 204, hits the inner surface of the fan casing 204, and has a substantially triangular shape. The effluent stream 20 is turned axially through 18. The outflow flow 20 has a swirl direction flow component, and the return guide vane 14 turns the swirl flow into a radially inward flow.

  The return guide blade 14 is provided so as to be located at the opening 34 of the housing 208. The flow turned inward in the radial direction by the return guide vanes 14 hits the cooling fins 27 of the bearing cover 215 from the openings 34 of the housing 208, and the bearings 212 are effectively cooled. Thereby, the electric blower 200 with high bearing reliability is obtained.

  Since the diffuser flow path formed by the fan casing 204, the diffuser blades 13 and the partition plate 15 is gently inclined, it can smoothly flow from the substantially triangular channel 18 to the return guide blades 14. Bending loss can be reduced. Thereby, fan efficiency can be improved. Moreover, sufficient airtightness is obtained by the cylindrical convex portion 17 of the return guide 205b and the concave portion 29 of the housing 208, and the blower efficiency can be improved.

  Next, a fan casing 204 according to an embodiment of the present invention will be described with reference to FIG. The fan casing 204 of one embodiment according to the present invention covers the centrifugal impeller 203 and the guide vane 205 from the outside, and is continuous with the upper plate 21 having a circular shape in plan view and the peripheral portion of the upper plate 21. And an annular side plate 22 extending in the direction. A protrusion 23 is provided at an end of the side plate 22 of the fan casing 204 on the side opposite to the upper plate 21, and a mounting hole 24 for fixing the fan casing 204 to the housing 208 is provided.

  An air suction port 206 is provided in the center of the upper plate 21 of the fan casing 204. A concave portion 204a is provided on the inner peripheral surface of the air suction port 206, and the straight portion 5 of the centrifugal impeller 203 is disposed in the concave portion 204a. The centrifugal impeller 203 is arranged so that there is a small gap between the fan casing 204 and the tip of the straight portion 5, and the amount of air leaked to the suction opening 4 side of the centrifugal impeller 203 is reduced. It has a structure. By disposing the sealing member in the recess 204a, the sealing effect can be enhanced, and the fan efficiency can be further improved.

  An airtight holding member 25 using an elastic body is disposed on the inner surface of the upper plate 21 of the fan casing 204. The airtight holding member 25 is made of an elastic material such as rubber or elastomer and is integrally formed with the fan casing 204. In this embodiment, the elastic member 25 and the fan casing 204 are integrally formed by insert molding. The rib 13 a provided on the diffuser blade 13 bites into the airtight portion holding member 25, whereby the airtightness between the fan casing 204 and the guide blade 205 is maintained. As a result, leakage between the diuser blades 13 of the guide vanes 205 can be prevented, and the fan efficiency can be improved.

  Next, an electric motor unit 202 according to an embodiment of the present invention will be described with reference to FIGS. 8A is a perspective view of an embodiment in which the bearing cover 215 and the housing 208 according to the present invention are integrated, FIG. 8B is a rear view, and FIG. 9 is A of the electric blower 200 of FIG. FIG. 10A is a longitudinal sectional view taken along line BB in FIG. 8A, FIG. 10B is a longitudinal sectional view taken along line CC, and FIG. It is a perspective view of one Example of the bearing cover by.

  The housing 208 is made of synthetic resin and has a support portion 26 that fixes a bearing cover 215 that encloses the bearing 212. The support portion 26 has a substantially double cylindrical shape and is located inside the front portion of the housing 208. A bearing cover 215 made of a nonmagnetic metal material is fixed to the substantially cylindrical portion 26 a inside the support portion 26. A plurality of cooling fins 27 that are long in the direction of the rotation axis, which is a heat sink for cooling the bearing 212, are provided on the substantially cylindrical portion 26 b on the outer periphery of the bearing cover 215, and are integrally formed with the support portion 26 of the housing 208. Due to the complicated shape in which the cooling fins 27 are provided on the outer periphery of the bearing cover 215, the production cost can be reduced and high dimensional accuracy can be obtained by manufacturing by die casting. The material used for the bearing cover 215 and the cooling fin 27 is preferably a nonmagnetic metal aluminum alloy having high thermal conductivity.

  In the present embodiment, the housing 208 is formed by insert molding using the bearing cover 215 as an insert product. A screw hole 28 extending in the rotation axis direction is formed at the end of the support portion 26 of the resin housing 208. A fixing screw 218 can be screwed into the screw hole 28, and the guide blade 205 is fixedly installed on the housing 208 by screwing the fixing screw 218.

  A recess 29 is provided on the outer diameter side of the screw hole 28. By fitting the concave portion 29 and the cylindrical convex portion 17 on the return guide 205b side, air leakage from the electric motor unit 202 side to the blower unit 201 side can be prevented.

  The outer peripheral portion of the support portion 26 is connected to a substantially cylindrical frame 31 by a bridge 30. A screw hole 32 for fixing the stator core 210 is provided at an end portion of the frame 31 where the bridge 30 is provided. A fixing screw 219 can be screwed into the screw hole 32, and the stator core 210 is fixedly installed on the housing 208 by screwing the fixing screw 219.

  Further, a claw-like protrusion 33 is provided at an end of the frame 31 on the blower unit 201 side, and is fitted and connected to the mounting hole 24 of the fan casing 204. Positioning accuracy in the axial direction of the fan casing can be ensured by connection by fitting instead of connection by adhesive, and airtightness between the fan casing 204 and the guide blade 205 can be secured. Moreover, the dispersion | variation in the front-end | tip clearance gap of the recessed part 204a of the fan casing 204 and the linear part 5 of the centrifugal impeller 203 can be made small, and the performance improvement and performance dispersion | variation of the electric blower 200 can be made small.

  The housing 208 has a plurality of openings 34 formed between the bridges 30 so that air flows into the housing 208, and a plurality of exhaust ports 35 that directly discharge the air to the outside without cooling the rotor core 209, the stator core 210, and the conductor 211. One is provided.

  An inclined portion 36 is provided inside the frame 31. Air that has flowed out of the substantially triangular shaped flow path 18 of the guide vane 205 is structured to easily flow into the opening 34 by the return guide blade 14 and the inclined portion 36. The air flowing from the opening 34 hits the cooling fins 27 that are long in the direction of the rotation axis, which is a heat sink provided in the bearing cover 215. The cooling fin 27 has a rectangular plate shape. The heat generated in the bearing 212 is transmitted through the bearing cover 215 made of a non-magnetic metal material by heat conduction, dissipated by the cooling fins 27, and the bearing 212 is effectively cooled.

  In the motor part 202, the mechanical loss generated in the bearing 212 is larger than the ratio of the copper loss generated in the conducting wire 211 wound around the stator core 210, and it is important to cool the bearing 212 effectively. Even if the housing 208 is made of resin, the heat generated in the bearing 212 can be effectively dissipated by the heat sink provided in the bearing cover 215, the bearing 212 can be effectively cooled, and the electric blower 200 has high reliability. Can be provided. Furthermore, since the housing 208 is made of resin, the housing 208 can be reduced in weight, and the electric blower 200 can be reduced in weight. In this embodiment, the bearing cover 215 and the resin housing 208 are integrated by insert molding, but the bearing cover 215 may be press-fitted into the resin housing 208.

  As shown in FIG. 9, the bearing cover 215 is provided so that the cooling fin 27 is disposed at the position of the opening 34 of the housing 208. The cooling fins 27 are not disposed on the bridge 30 portion of the housing 208. Further, as shown in FIG. 8B, the bridge 30 is provided with a rib 26c instead of the cooling fin 27. The rib 26 c is connected to the bridge 30 and the substantially double cylindrical support portion 26 (26 a, 26 b) of the support portion of the housing 208, and has an effect of increasing the rigidity of the housing 208.

  The air having the swirl flow component flowing out from the substantially triangular flow path 18 is turned by the return guide vane 14 into a swirl flow inward in the radial direction and directly hits the cooling fins 27 of the heat sink. A sufficient cooling effect can be obtained. A sufficient cooling effect can be obtained without providing the cooling fins 27 on the bridge 30 part, and the number of cooling fins can be reduced compared with the number of cooling fins evenly provided in the circumferential direction, and the weight can be reduced while providing a sufficient heat dissipation effect. The effect of can also be produced.

  The resin housing 208 and the nonmagnetic metal material bearing cover 215 are integrated by insert molding. As shown in FIG. 10, the support portion 26 of the housing has a substantially double cylindrical shape, and the support portion 26 a on the inner diameter side extends to almost the same end as the end of the cooling fin 27. The support portion 26b on the radial side is about half the length of the cooling fin 27.

  Since the cooling fin 27 is provided on the bearing cover 215, the bearing cover 215 has high rigidity so that the cooling fin 27 is included by the substantially cylindrical portion 26a on the inner side and the substantially cylindrical portion 26b on the outer side of the substantially double cylindrical support portion 26 ( Since the housing 208 is integrally formed (so that the cooling fin 27 crosses the inner substantially cylindrical portion 26a and the outer substantially cylindrical portion 26b), the rigidity of the bearing cover 215 and the housing 208 can be increased, and 80 / min. , 000 rotations or more can be achieved.

  In the present embodiment, the outer diameter side support portion 26b is about half of the length of the cooling fin 27. However, if the rigidity of the housing 208 is sufficiently high, the outer diameter side support portion 26b is formed on the outer diameter side in order to enhance the cooling effect. The length of the support portion 26b may be shortened, and the length of the portion of the cooling fin 27 that receives the cooling air may be increased.

  A cylindrical reference surface 37 on which the cooling fins 27 are not provided is provided at the end of the bearing cover 215. The reference surface 37 is a reference surface when the bearing cover 215 and the resin housing 208 are insert-molded, and serves as a reference for the inner diameter cutting for fixing the outer ring of the bearing 212. By making the reference surface 37 into a cylindrical shape, the reference surface at the time of internal diameter cutting by a lathe or the like can be easily configured. In addition, the number of places to be machined by a lathe can be reduced. As a result, the dimensional accuracy is improved, the center axis of the stator core 210 attached to the housing 208 and the center axis of the rotor core 209 attached to the rotary shaft 207 are matched, the efficiency of the electric motor unit 202 is improved, and further vibration and noise are reduced. An electric blower that can be reduced can be obtained. In this embodiment, the reference surface has a cylindrical shape. However, the reference surface is not limited to this, and may be a polyhedron shape. Any shape can be used as long as the reference for cutting the inner diameter and the reference for insert molding of the housing 208 can be used. good.

  Here, the rotor core 209 is magnetized and then incorporated into the housing 208. However, since the bearing cover 215 is made of a nonmagnetic metal, it is not affected by the attractive force of the magnet and is excellent in assemblability. .

  In this embodiment, a plurality of cooling fins 27 that are long in the direction of the rotation axis are used as heat sinks, and the cooling fins 27 have a rectangular plate shape, but may have a pin shape such as a large number of cylindrical shapes, conical shapes, and prismatic shapes. In other words, any shape may be used as long as the cooling fin 27 protrudes in the circumferential direction so that the cooling fin 27 crosses the inner substantially cylindrical portion 26a and the outer approximately cylindrical portion 26b in order to radiate heat from the bearing. By adopting a pin shape, the volume can be reduced to obtain the same surface area, and the mass can be reduced.

  According to the electric blower 200 of the present embodiment described above, the resin material melted by welding does not protrude into the flow path of the centrifugal impeller 203, and the airtightness in the flow path can be reliably obtained. Thereby, the efficiency of the electric blower 200 can be improved reliably.

  Further, the inclined surface 12 is formed on the front edge side of the centrifugal impeller 203 so as to coincide with the shape of the curved surface portion 6 of the shroud plate 1. During operation, the front edge side works so that the curved surface portion 6 of the shroud plate 1 and the inclined portion 12 of the blade 3 are in close contact with each other, so there is no gap between the blade 3 and the shroud plate 1 on the inlet side of the centrifugal impeller 203. The efficiency of the electric blower 200 can be improved.

  Furthermore, since the diffuser flow path formed by the fan casing 204, the diffuser blades 13 and the partition plate 15 is gently inclined, it flows smoothly from the substantially triangular channel 18 to the return guide blades 14. And bending loss can be reduced. Thereby, fan efficiency can be improved.

  Further, the rib 13 a provided on the diffuser blade 13 bites into the airtight portion holding member 25 of the fan casing 204, whereby the airtightness between the fan casing 204 and the guide blade 205 is maintained. As a result, leakage between the diuser blades 13 of the guide vanes 205 can be prevented, and the fan efficiency can be improved.

  Further, by fitting the concave portion 29 of the housing 208 and the cylindrical convex portion 17 of the guide blade 205, leakage from the electric motor portion 202 side to the blower portion 201 side can be prevented, and the blower efficiency can be improved. it can.

  Furthermore, even if the housing 208 is made of resin, the heat generated in the bearing 212 can be effectively dissipated by the heat sink provided in the bearing cover 215, the bearing 212 can be effectively cooled, and the reliability is high. The electric blower 200 can be reduced in weight.

  A cylindrical reference surface 37 on which the cooling fins 27 are not provided is provided at the end of the bearing cover 215. By using this reference surface 37 as a bearing cover 215 and a resin housing 208 as a reference surface for inner diameter cutting that fixes the reference surface at the time of insert molding and the outer ring of the bearing 212, the dimensional accuracy is improved and the housing 208 is attached. The stator core 210 and the central axis of the rotor core 209 attached to the rotating shaft 207 coincide with each other, so that the efficiency of the electric motor unit 202 can be improved, and an electric blower that can further reduce vibration and noise can be obtained.

  Further, by producing the bearing cover 215 by aluminum die casting, the production cost can be reduced and high dimensional accuracy can be obtained.

  Further, by cutting the balance adjusting ring 213 attached to the convex portion 2a of the centrifugal impeller 203 and the shaft end of the rotating shaft 207, the two-surface balance can be corrected, and vibration and noise are reduced. An electric blower that can be obtained can be obtained.

  Further, since the bearing cover 215 is made of a nonmagnetic metal, it is not affected by the attractive force of the magnet, and a highly reliable electric blower excellent in assemblability can be obtained.

  By mounting the electric blower 200 on the vacuum cleaner, the output of the vacuum cleaner can be improved. Further, by improving the efficiency of the electric blower 200, the input of the electric blower 200 can be lowered when the same output is obtained, and the operation time can be extended in the rechargeable cleaner using a battery as a drive source. .

Reference Signs List 1 shroud plate 2 hub plate 3 blade 4 suction opening 5 linear portion 6 curved portion 7 concave groove 8 through hole 9 boss 10 projecting claw 11 rib 12 inclined surface 13 diffuser blade 14 return guide blade 15 partition plate 16 through hole 17 convex Portion 18 Approximately triangular channel 19 Inflow flow to diffuser blade 20 Outflow flow from diffuser blade 21 Fan casing upper plate 22 Fan casing side plate 23 Projection 24 Mounting hole 25 Airtight holding member 26 Housing support portion 27 Cooling fin 28 Screw hole DESCRIPTION OF SYMBOLS 29 Recess 30 Bridge 31 Frame 32 Screw hole 33 Claw-shaped protrusion 34 Open 35 Exhaust port 36 Inclined part 37 Reference plane 100 Vacuum cleaner body 200 Electric blower 201 Blower part 202 Electric motor part 203 Centrifugal blower 204 Fan casing 205 Guide vane 205a De Fuser 205b return guide 206 inlet 207 rotating shaft 208 housing 209 rotor core 210 stator 211 conductor 212 bearing 213 balance adjustment ring 214 positioning sleeve 215 bearing cover 216 sleeve 217 spring 218 guide vane fixing screw 219 stator core fixing screw

Claims (4)

A rotating shaft provided rotatably, a rotor core formed integrally with one end of the rotating shaft, a centrifugal impeller attached to the other end of the rotating shaft, and between the rotor core and the centrifugal impeller A bearing to which the rotating shaft is attached;
A bearing cover containing the bearing, and a resin housing integrally formed with the bearing cover,
A diffuser blade, a guide blade having a return guide blade on the back surface of the diffuser blade, and a fan casing containing the centrifugal impeller and the guide blade,
A heat sink is provided on the outer periphery of the bearing cover, and a reference surface not provided with the heat sink is provided on a side surface of the bearing cover,
The reference plane is a reference plane at the time of insert molding of the bearing cover and the resin housing and a reference at the time of inner diameter cutting for fixing the outer ring of the bearing, and an electric blower including the electric blower Electric vacuum cleaner.   2. The electric blower according to claim 1, wherein the bearing cover is made of a nonmagnetic metal material, and a vacuum cleaner provided with the electric blower.   3. The electric blower according to claim 1 or 2, and an electric vacuum cleaner provided with the electric blower, wherein the heat sink has a plurality of fin shapes or a plurality of pin shapes long in the rotation axis direction. In the electric blower according to any one of claims 1 to 3,
An electric blower characterized in that the bearing cover is manufactured by die casting and integrated with the resin housing by insert molding, and a vacuum cleaner provided with the electric blower.