JP2016223334A - Blower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blower capable of directly cooling the inside of an electric motor by using a recirculating air flow.SOLUTION: A blower 3 includes an outer rotor type electric motor 10, and an impeller 30 having a hub 31 covering a rotor yoke 20 of the electric motor 10 in the axial direction and a plurality of vanes 34 fixed to the hub 31. The rotor yoke 20 has a yoke through-hole 22a passing therethrough in the axial direction, and the hub 31 has a hub through-hole 32b passing therethrough in the axial direction so as to communicate with the yoke through-hole 22a. Part of an air flow generated by the rotation of the impeller 30 passes through the inside of the electric motor 10 in the axial direction to form a recirculating air flow RA which passes through the yoke through-hole 22a and the hub through-hole 32b, in sequence. To the hub 31, a hub cover 50 is mounted as a straightening mechanism for straightening the recirculating air flow RA passing through the hub through-hole 32b into an air flow which moves to the vanes 34.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a blower, and more particularly to a rectifying mechanism for a recirculated airflow formed in the blower.

  For example, a blower used for an air conditioner is generally known to have a configuration in which a hub of an impeller is fixed to an output shaft of an inner rotor type electric motor. Further, in order to cool the electric motor, a configuration in which a part of the suction main flow generated by the rotation of the impeller is used as air cooling of the housing of the electric motor and a recirculation air flow that joins the suction main flow again is widely known. Yes.

  As a blower having such a configuration, for example, the blower of Patent Document 1 has a configuration in which a hub of an impeller is fixed to an output shaft of an inner rotor type electric motor, and has a truncated cone shape for forming a recirculation airflow. A plurality of through holes formed on the side peripheral surface of the hub, and a hub cover that covers the through holes. The hub cover is fixed to the impeller. According to this configuration, a part of the suction main flow passing between the blades adjacent to each other in the circumferential direction passes through the periphery of the electric motor housing from the side opposite to the blades on the main plate of the impeller as a recirculation airflow. The airflow flowing out toward the outer side in the radial direction of the hub through the through-holes flows along the inclined portion of the hub.

JP-A-11-101194

  However, in a blower including an inner rotor type electric motor, components such as a rotor and a stator of the electric motor are sealed by the housing, so that the recirculated airflow only contacts the outer surface of the housing and cools down. It is difficult to cool the inside of the motor efficiently.

  In order to solve the above-described problems, an object of the present invention is to provide a blower that can directly cool the inside of an electric motor by a recirculation airflow.

  A blower that solves this problem includes a coil that generates a magnetic field, a cup-shaped rotor yoke that rotates around a rotating shaft and covers one of the coils in the axial direction and the outside of the coil in the radial direction, and the radial direction. An outer rotor type electric motor comprising a permanent magnet held by the rotor yoke in a state of being opposed to each other with a gap on the outside of the coil, a hub covering the rotor yoke in the axial direction, and a plurality fixed to the hub The rotor yoke is provided with an impeller that rotates integrally with the rotor yoke, and the rotor yoke is provided with a yoke through-hole penetrating in the axial direction, and the hub is provided with the yoke. A hub through hole penetrating in the axial direction is formed so as to communicate with the through hole, and a part of the air flow generated by the rotation of the impeller A recirculation airflow that passes through the coil in the axial direction and sequentially passes through the yoke through hole and the hub through hole is formed, and the hub heads the recirculation airflow that has passed through the hub through hole toward the blades. It has a rectifying mechanism that rectifies airflow.

  According to this configuration, the coil in the electric motor can be directly cooled by the recirculation airflow. And since the recirculation airflow which passed the hub through-hole goes to a blade | wing by a rectification | straightening mechanism, it is suppressed that the suction main flow and recirculation airflow which arise by rotation of an impeller collide. Therefore, an increase in the noise of the blower can be suppressed.

  In the blower, the rectifying mechanism is a hub cover attached to the opposite side of the rotor yoke with respect to the hub in the axial direction, and the hub cover is opposed to the hub with a gap in the axial direction. It is preferable to have a part.

  According to this structure, compared with the case where a rectification | straightening mechanism is integrally formed in the hub of an impeller, the shape of a hub can be simplified. For this reason, the metal mold | die structure for manufacturing a hub can be simplified.

  In the blower, it is preferable that the hub has an inclined portion that is inclined toward the outer side in the radial direction, and the hub cover has an inclined cover portion that covers at least an inner portion in the radial direction of the inclined portion.

  According to this configuration, since the recirculated airflow that has passed through the hub through hole flows along the inclined portion of the hub by the inclined cover portion, the collision with the suction main flow caused by the rotation of the impeller is further suppressed. can do.

In the blower, the rectifying mechanism is preferably formed integrally with the hub.
According to this structure, compared with the case where a rectification | straightening mechanism and a hub are formed separately, the number of parts of a fan can be decreased.

  In the blower, rotation of the impeller is limited to one direction, and the rectifying mechanism covers at least a part of the hub through-hole from the side opposite to the rotor yoke in the axial direction, and the blade It is preferable to have a rectification inclination part which inclines toward the said hub as it goes to the front or back of the rotation direction of a vehicle.

  According to this configuration, since the airflow passing through the rectifying inclined portion flows along the rectifying inclined portion, it is possible to suppress the generation of vortices in front of or behind the rotating direction of the rectifying mechanism. Therefore, an increase in the noise of the blower can be suppressed.

  According to this blower, since the recirculation airflow flows into the electric motor by using the outer rotor type electric motor, the inside of the electric motor can be directly cooled by the recirculation airflow.

1 is a schematic cross-sectional view illustrating an overall configuration of a ceiling-embedded air conditioner that employs a blower according to a first embodiment. It is a longitudinal cross-sectional view of a part of the blower. It is a disassembled perspective view of the rotor yoke of the same air blower, an impeller, a connection member, and a hub cover. It is a longitudinal cross-sectional view for recirculation airflow description of the air blower. It is a longitudinal cross-sectional view for recirculation airflow description of the air blower which concerns on a comparative example. It is a perspective view of the hub of the air blower of a 2nd embodiment. It is a top view of the hub of the impeller. It is a longitudinal cross-sectional view for recirculation airflow description of the air blower. It is operation | movement explanatory drawing of the air blower, (a) is a side view of the through-hole cover in the hub of the air blower, (b) is a side view of the through-hole cover in the hub of the air blower concerning a comparative example. It is a perspective view of the hub and hub cover of the air blower concerning a modification. It is a perspective view of the hub of the air blower concerning other modifications. It is a perspective view of the hub of the air blower concerning another modification.

(First embodiment)
With reference to FIG. 1, the schematic configuration of a ceiling-embedded air conditioner equipped with a blower according to the first embodiment will be described.

  The ceiling-embedded air conditioner is inserted and disposed in an opening H formed in the ceiling R. This ceiling-embedded air conditioner includes a main body casing 1 disposed behind the ceiling and a decorative panel 2 disposed below the main body casing 1. The decorative panel 2 is attached through the opening H, and is connected to the main body casing 1 on the upper surface side.

  The main casing 1 is formed in a box shape having a substantially rectangular shape in plan view. In the internal space surrounded by the main body casing 1 and the decorative panel 2, the blower 3 that sucks indoor air into the main body casing 1 through the suction port 2 a of the decorative panel 2 and blows it out in the outer peripheral direction, and the outer periphery of the blower 3 are surrounded. The indoor side heat exchanger 4 arrange | positioned in this way is arrange | positioned.

  The decorative panel 2 is a plate-like body having a substantially rectangular shape in plan view, and a suction port 2a for sucking indoor air is formed in the center, and indoor side heat exchange is performed on each of the four sides located around the suction port 2a. The blower outlet 2b which blows off the air conditioned by the vessel 4 is formed. The suction port 2a is provided with a suction grill 2c and an air filter 5 that removes dust in the air sucked from the suction port 2a.

  The blower 3 is a turbo fan, and includes an electric motor 10 provided below the central portion of the top plate of the main casing 1 and an impeller 30 that is directly connected to the electric motor 10 and rotates integrally with the electric motor 10. Have.

  As shown in FIG. 1, the electric motor 10 is fixed by bolts on a plurality of support pillars 1 a extending downward from the main body casing 1. That is, a gap is formed between the electric motor 10 and the main body casing 1.

  The impeller 30 is formed by resin molding. The impeller 30 has a circular hub 31 that is directly connected to the electric motor 10, a plurality of blades 34 provided on the outer periphery of the lower surface of the hub 31, a lower side of the blade 34, and an opening at the center. And a shroud 35. The blower 3 sucks air into the inside of the impeller 30 through the opening of the shroud 35 by the rotation of the impeller 30, and blows out the sucked air to the outer peripheral side of the impeller 30.

  The indoor side heat exchanger 4 is a cross fin coil type, and is connected to an outdoor unit (not shown) via a refrigerant pipe. The indoor heat exchanger 4 functions as an evaporator during the cooling operation and as a condenser during the heating operation, and adjusts the temperature of the air blown from the blower 3. A drain pan 6 that receives drain generated in the indoor heat exchanger 4 is disposed below the indoor heat exchanger 4. An opening is provided at the center of the drain pan 6. This opening is located at a position corresponding to the air suction port at the center of the shroud 35 and is provided with a bell mouth 7.

  In this way, an air flow passage extending from the suction port 2a of the decorative panel 2 to the air outlet 2b is formed. In the air flow passage, a suction grill 2c, an air filter 5, a bell mouth 7, a blower 3, and an indoor heat exchanger 4 are arranged in this order from upstream to downstream.

Next, the detailed configuration of the electric motor 10 and the hub 31 of the impeller 30 will be described with reference to FIGS.
As shown in FIG. 2, the electric motor 10 includes a stator 10S that generates a magnetic field, a rotor 10R that rotates based on the magnetic field generated by the stator 10S, and a substantially cylindrical support member 11 that supports the stator 10S and the rotor 10R. And a base 12 to which the support member 11 is attached. The base 12 is fixed to the column 1a of the main casing 1 shown in FIG. The electric motor 10 is a so-called outer rotor type motor in which the rotor 10R is disposed on the radially outer side of the stator 10S.

  The stator 10 </ b> S is supported on the outer peripheral portion of the support member 11. The stator 10 </ b> S includes a stator core 13 formed by laminating a plurality of electromagnetic steel plates, and a coil 14 formed by winding an electric wire around the stator core 13.

  The coil 14 generates a magnetic field when electric power is supplied to the electric wire. The coil 14 of this embodiment is a so-called concentrated winding coil in which a plurality of coils are formed by winding an electric wire around each of a plurality of teeth of the stator core 13. Note that the coil 14 may be a so-called distributed winding coil wound around a plurality of teeth of the stator core 13.

  The rotor 10R includes a shaft 15 serving as a rotation shaft, a cylindrical boss 16 fixed to the shaft 15, a cup-shaped rotor yoke 20 fixed to the outer peripheral surface of the boss 16, and a ring-like shape held by the rotor yoke 20. And a permanent magnet 17.

  The shaft 15 is inserted into the support member 11 and is rotatably supported with respect to the support member 11 by two bearings 18 attached in the support member 11. An example of the bearing 18 is a rolling bearing such as a ball bearing. The bearing 18 may be a bearing other than a rolling bearing (for example, a sliding bearing) as long as the shaft 15 can be rotatably supported with respect to the support member 11.

  The boss 16 is fixed to the lower portion of the shaft 15 in the axial direction than the support member 11 by press-fitting or bonding. The upper surface of the boss 16 is in contact with the lower surface of the inner ring of the bearing 18 on the lower side in the axial direction.

  The rotor yoke 20 is formed by pressing a magnetic steel plate. The rotor yoke 20 rotates around the central axis of the shaft 15 to cover the coil 14 (stator 10S) from the lower side in the axial direction and the outer side in the radial direction. The rotor yoke 20 includes a cylindrical magnet holding portion 21 that holds the permanent magnet 17, a substantially disk-shaped stator cover portion 22 that covers the stator 10 </ b> S from the lower side in the axial direction, and a gap between the magnet holding portion 21 and the stator cover portion 22. And a step portion 23 forming a step shape. The permanent magnet 17 is positioned in the axial direction by contacting the stepped portion 23 in the axial direction. And the permanent magnet 17 is arrange | positioned in the state which left the clearance gap and the outer side of the coil 14 (stator 10S) in radial direction.

  The stator cover part 22 has a lower surface parallel to a plane direction orthogonal to the axial direction. At the center of the stator cover portion 22, a cylindrical fixing portion 24 that protrudes downward in the axial direction is formed. The boss 16 is fixed to the fixing portion 24 by press-fitting or bonding.

  As shown in FIG. 3, three yoke through holes 22 a are formed in the outer peripheral portion of the stator cover portion 22. The yoke through hole 22a is formed in an arc shape in plan view with the center of the stator cover portion 22 being the center position of the radius of curvature, and penetrates the stator cover portion 22 in the axial direction.

  The yoke through holes 22a are formed at 120 ° intervals in the circumferential direction. In addition, six screw holes 22 b are formed around the fixed portion 24 in the inner peripheral portion of the stator cover portion 22. The six screw holes 22b are formed at 60 ° intervals in the circumferential direction.

A hub 31 of an impeller 30 is attached to the stator cover portion 22. As a result, the impeller 30 can rotate integrally with the rotor yoke 20.
As shown in FIGS. 2 and 3, the hub 31 is continuous with the yoke cover portion 32 that covers the rotor yoke 20 from the lower side in the axial direction, and the yoke cover portion 32. It is formed in a substantially truncated cone shape having an inclined portion 33 that is inclined.

  As shown in FIG. 3, the yoke cover portion 32 has a fitting hole 32 a fitted into the fixing portion 24, three hub through holes 32 b, three large diameter through holes 32 c, and three small diameters. Through-holes 32d. The fitting hole 32a, the hub through hole 32b, the through hole 32c, and the through hole 32d penetrate the yoke cover portion 32 in the axial direction.

  The hub through hole 32b is formed in a circular arc shape in plan view with the center of the yoke cover portion 32 being the center position of the radius of curvature at a position facing the yoke through hole 22a in the axial direction. The opening area of the hub through hole 32b is larger than the opening area of the yoke through hole 22a. Specifically, the width dimension of the hub through-hole 32b, that is, the hole dimension in the radial direction is equal to or larger than the hole dimension in the radial direction of the yoke through-hole 22a, and the length dimension of the hub through-hole 32b, that is, the hole dimension in the circumferential direction is It is not less than the hole size in the circumferential direction of the yoke through hole 22a.

  The through holes 32c and 32d are formed on the radially inner side than the hub through hole 32b. The through holes 32c are formed at the same phase angle as the hub through holes 32b, and the through holes 32d are formed between the hub through holes 32b in the circumferential direction. The hub 31 is fixed to the rotor yoke 20 by inserting three screws 36 into the three through holes 32c of the yoke cover portion 32 and screwing into the three screw holes 22b.

  A connecting member 40 is attached to the center of the yoke cover portion 32. The connection member 40 includes a hub attachment portion 41 attached to the center of the yoke cover portion 32 and a columnar fitting portion 42 extending from the hub attachment portion 41 in the axially lower side. The hub attachment portion 41 includes a cylindrical portion 41a that is continuous with the fitting portion 42, and a flange 41b that extends radially outward from the upper end portion of the cylindrical portion. In the flange 41b, three through holes 41c are formed through which the three screws 37 are inserted. A small-diameter cylindrical screw fixing portion 42 a is formed at the lower end portion of the fitting portion 42. The connecting member 40 has three screws 37 inserted into the three through holes 41c of the flange 41b and the three through holes 32d of the yoke cover portion 32 and screwed into the three screw holes 22b. 31 is fixed.

A hub cover 50 is attached to the connection member 40 as a rectifying mechanism that covers the hub 31 from the lower side in the axial direction.
The hub cover 50 is continuous with the cover portion 51 facing the yoke cover portion 32 with a gap in the axial direction, and the cover portion 51. The hub cover 50 is inclined to the upper side in the axial direction as it goes radially outward. Are formed in a substantially truncated cone shape.

  A cylindrical fitting portion 51 a extending toward the upper side in the axial direction is formed at the center of the cover portion 51. The hub cover 50 is fixed to the connecting member 40 by screwing the screw 53 into the screw fixing portion 42a in a state where the fitting portion 51a is fitted to the screw fixing portion 42a of the connecting member 40. The lower surface of the cover 51 extends in a plane direction orthogonal to the axial direction, and is formed by a flat surface having no irregularities. Further, it smoothly continues in a curved shape from the outer peripheral side of the cover portion 51 to the inner peripheral side of the inclined cover portion 52. Thereby, the hub cover 50 guides the suction main flow MA (see FIG. 4), which is an air flow sucked into the impeller 30 by the rotation of the impeller 30, to the inclined portion 33 of the hub 31.

  As shown in FIG. 2, the cover portion 51 of the hub cover 50 faces the hub through hole 32 b of the hub 31 in the axial direction. The cover part 51 is smaller than the yoke cover part 32 of the hub 31. Therefore, the inclined cover portion 52 of the hub cover 50 covers the outer peripheral side of the planar portion of the yoke cover portion 32. Further, the inclined cover portion 52 of the hub cover 50 covers the inner peripheral side of the inclined portion 33 of the hub 31 and forms a steeper inclination than the inclined portion 33. For this reason, as shown in FIG. 2, the gap G <b> 2 between the outer peripheral end portion of the inclined cover portion 52 and the inclined portion 33 is smaller than the gap G <b> 1 between the cover portion 51 and the yoke cover portion 32. Further, the gap between the hub cover 50 and the hub 31 is constant at the portion corresponding to the cover portion 51, and gradually decreases at the portion corresponding to the inclined cover portion 52 toward the outer side in the radial direction.

  According to such a configuration, as shown in FIG. 4, a part of the air blown out from the impeller 30 passes between the hub 31 and the top plate of the main body casing 1, and the plurality of through holes in the base 12. A recirculating airflow RA is formed that enters the electric motor 10 via 12a, cools the electric motor 10, and joins the suction main flow MA again to be blown out from the impeller 30. Specifically, the air flowing into the electric motor 10 cools the stator 10S by passing between the coils 14 adjacent in the circumferential direction in the axial direction. The air whose temperature has been increased by cooling the stator 10S is parallel to the gap between the hub 31 and the hub cover 50 in the axial direction through the yoke through hole 22a (see FIG. 2) of the rotor yoke 20 and the hub through hole 32b of the hub 31. It flows out to become. The air flowing into the gap is rectified by the cover portion 51 of the hub cover 50 so as to be an air flow toward the blades 34, and then further rectified by the inclined cover portion 52 so as to be substantially parallel to the suction main flow MA. . The air flowing out from between the inclined cover portion 52 and the inclined portion 33 of the hub 31 is attracted by the suction main flow MA and merges with the suction main flow MA.

  Next, with reference to FIG. 4 and FIG. 5, the effect | action of the air blower 3 of this embodiment is demonstrated. FIG. 5 shows a blower 100 according to a comparative example, in which the connection member 40 and the hub cover 50 are omitted from the blower 3. In addition, in the air blower 100, about the structure common to the air blower 3, the same code | symbol is used and the description is abbreviate | omitted.

  As shown in FIG. 5, in the blower 100, the air of the recirculated airflow RA that flows out from the yoke through hole 22a of the rotor yoke 20 and the hub through hole 32b of the hub 31 flows out along the axial direction. As a result, a vortex (turbulent flow) is generated. This vortex flows radially outward by the suction main flow MA and interferes with the blades 34. Thereby, in the air blower 100, the noise resulting from a vortex generate | occur | produces.

  On the other hand, as shown in FIG. 4, in the blower 3, as described above, the recirculation air flow RA is rectified by the hub cover 50 and merges with the suction main flow MA in a state substantially parallel to the suction main flow MA. Generation of (turbulent flow) is suppressed. Therefore, the blower 3 has less noise than the blower 100.

Since the air blower 3 of this embodiment is comprised as mentioned above, there can exist the following effects.
(1) The blower 3 includes an outer rotor type electric motor 10. For this reason, the recirculation air flow RA of the blower 3 flows into the electric motor 10 through the through hole 12 a of the base 12. For this reason, the stator 10S in the electric motor 10 can be directly cooled.

  Further, the blower 3 rectifies the recirculated air flow RA flowing out along the axial direction through the yoke through hole 22a of the rotor yoke 20 and the hub through hole 32b of the hub 31 into the air flow toward the blades 34 in the same manner as the main flow MA. A hub cover 50 as a rectifying mechanism is provided. For this reason, the air of the recirculation air flow RA that has cooled the stator 10S receives an attractive action when it joins the suction main flow MA and smoothly merges with the suction main flow MA. Therefore, an increase in noise of the blower 3 can be suppressed.

  (2) Since the hub cover 50 is formed separately from the impeller 30, the shape of the hub 31 portion of the impeller 30 is simplified. For this reason, the metal mold | die structure for manufacturing the impeller 30 can be simplified.

  (3) The recirculation air flow RA becomes an air flow along the inclined portion 33 of the hub 31 by the inclined cover portion 52 of the hub cover 50 and the inclined portion 33 of the hub 31. For this reason, it becomes difficult for the recirculation airflow RA to collide with the suction main flow MA, and merges with the suction main flow MA more smoothly.

  (4) The gap between the hub cover 50 and the hub 31 includes a portion that gradually decreases toward the outside in the radial direction, that is, toward the downstream of the recirculation airflow RA. For this reason, since recirculation airflow RA is rectified, generation | occurrence | production of a turbulent flow is suppressed compared with the structure where the clearance gap between the hub cover 50 and the hub 31 becomes small suddenly. Therefore, the generation of noise of the blower 3 is further suppressed.

(Second Embodiment)
With reference to FIGS. 6-9, the structure of the air blower 3 of 2nd Embodiment is demonstrated. In addition, in the air blower 3 of 2nd Embodiment, a common code | symbol is used for the component which is common in the structure of the air blower 3 of 1st Embodiment, and the one part or all part of the description is abbreviate | omitted.

The blower 3 (see FIG. 8) of the present embodiment is different from the blower 3 of the first embodiment in that the rectifying mechanism is changed.
Specifically, in the first embodiment, the hub cover 50 (see FIG. 4) is provided as a member constituting the rectifying mechanism. However, in the second embodiment, instead of the hub cover 50, the hub through hole 32b is provided. The through hole cover 60 is molded integrally with the hub 31 as a rectifying mechanism. Therefore, in the second embodiment, the connecting member 40 (see FIG. 4) for attaching the hub cover 50 is also omitted.

  As shown in FIG. 6, in the impeller 30, a through hole cover 60, which is an example of a rectifying mechanism that covers the three hub through holes 32 b of the yoke cover portion 32 from the axial direction, is integrally formed with the hub 31. Thus, it is different from the impeller 30 of the first embodiment. Moreover, in the air blower 3 of this embodiment, the electric motor 10 (refer FIG. 2) is controlled so that the impeller 30 rotates only in one direction of rotation direction RD.

  The through-hole cover 60 has a curved convex rear wall portion 61 as an example of a rectifying and tilting portion that inclines toward the yoke cover portion 32 toward the rear in the rotational direction RD of the impeller 30, and the rotational direction of the impeller 30. A curved convex front wall portion 62 as an example of a rectifying inclined portion that inclines toward the yoke cover portion 32 toward the front of the RD. The rear wall portion 61 and the front wall portion 62 are formed at positions adjacent to the hub through-hole 32b in the circumferential direction, and partially cover the hub through-hole 32b from the lower side in the axial direction. The through hole cover 60 includes a flat portion 63 that connects the outer peripheral portion of the rear wall portion 61 and the outer peripheral portion of the front wall portion 62 in the circumferential direction. The flat part 63 is parallel to the plane direction orthogonal to the axial direction. On the inner edge of the flat portion 63, a curved convex inner peripheral inclined portion 64 that is inclined toward the yoke cover portion 32 as it goes radially inward is formed (see FIG. 8). The inner peripheral inclined portion 64 extends radially inward from the hub through hole 32b. Further, as shown in FIG. 6, the through-hole cover 60 opens toward the radially outer side.

  As shown in FIG. 7, the through hole cover 60 is formed at the same phase angle as the hub through hole 32b, and covers the entire hub through hole 32b from the axial direction. The through hole cover 60 is formed in an arc shape in plan view with the center of the yoke cover portion 32 being the center position of the radius of curvature.

  As shown in FIG. 8, the recirculation airflow RA passes in the axial direction in the order of the interior of the electric motor 10, the yoke through hole 22a (see FIG. 2), and the hub through hole 32b, as in the first embodiment. To do. Then, the air of the recirculated air flow RA flowing out from the hub through-hole 32b along the axial direction is rectified in the plane direction orthogonal to the axial direction by the through-hole cover 60 and flows toward the blades 34, and merges with the suction main flow MA. .

  9A, when the impeller 30 rotates, the three through-hole covers 60 revolve around the shaft 15 as the yoke cover portion 32 rotates. At this time, an air flow FA along the order of the front wall portion 62, the flat portion 63, and the rear wall portion 61 is formed in the through hole cover 60.

Since the blower 3 of the present embodiment is configured as described above, in addition to the effect (1) of the first embodiment, the following effects can be achieved.
(5) Since the through hole cover 60 as the rectifying mechanism is integrally formed with the impeller 30 by resin molding, compared with the case where the impeller 30 and the rectifying mechanism (through hole cover 60) are formed separately. The number of parts of the blower 3 can be reduced.

  (6) Since the through hole cover 60 includes the rear wall portion 61 and the front wall portion 62, the air flow FA passing through the wall portions 61 and 62 circulates along the wall portions 61 and 62. For this reason, in the through-hole cover 60, generation | occurrence | production of turbulent flows, such as a vortex, is suppressed before and behind the rotation direction RD. Therefore, an increase in noise of the blower 3 can be suppressed.

  (7) The blades 34 extend on both sides in the axial direction from the yoke cover portion 32 of the hub 31. When the resin is molded, the blades are molded using a slide core that can move in the plane direction intersecting the axial direction in the mold. For this reason, it is difficult to use a slide core for the yoke cover portion 32 of the hub 31. For this reason, the yoke cover part 32 needs to be molded only by a mold movable in the axial direction.

  In such a mold restriction, as the blower according to the comparative example shown in FIG. 9B, the peripheral wall 111 extends along the axial direction, and the bottom wall 112 that connects the front end surfaces of the peripheral wall 111 to the peripheral wall 111. When the cover part 110 having a rectangular shape in side view and connected vertically is molded with a mold, a turbulent flow is generated in the air flow FA as the impeller rotates. Specifically, turbulent flow is generated when the air flow FA collides with the peripheral wall 111 in the front in the rotational direction RD, and the air flow FA from the bottom wall 112 toward the peripheral wall 111 in the rear in the rotational direction RD peels from the cover 110. This causes turbulence. Thereby, the noise of an air blower becomes large.

  In view of this, it is conceivable to form an annular cover portion 110 in which the peripheral wall 111 is omitted by filling a portion between the peripheral walls 111 that easily generate turbulence with resin. However, when the portion between the peripheral walls 111 is filled with resin in the hub, the amount of resin used for molding is increased compared with the impeller 30 and the cost is increased.

  In view of such a point, the through-hole cover 60 shown in FIG. 9A suppresses the occurrence of turbulence by the wall portions 61 and 62 as described above. Thereby, since generation | occurrence | production of a turbulent flow can be suppressed, without increasing the quantity of resin used for shaping | molding, the cost increase of the impeller 30 can be suppressed.

(Modification)
The description regarding each said embodiment is an illustration of the form which the air blower according to this invention can take, and is not intending restrict | limiting the form. The blower according to the present invention can take a form in which, for example, modifications of the above-described embodiments described below and at least two modifications not contradicting each other are combined.

  In the first embodiment, the blower 3 may include a hub cover 70 as shown in FIG. 10 instead of the hub cover 50. The hub cover 70 is formed in a disk shape, and is formed with a recess 71 that opens outward in the radial direction at a location corresponding to the hub through hole 32 b of the hub 31. Thereby, the hub cover 70 faces the hub through hole 32b with a gap in the axial direction. Moreover, the recessed part 71 is formed so that the width | variety of the circumferential direction may become large as it goes to radial direction outer side. The inner edge of the recess 71 is located on the radially inner side of the hub through hole 32b. The circumferential width of the recess 71 at a position corresponding to the hub through hole 32b is larger than the circumferential width of the hub through hole 32b. Further, as shown in FIG. 10, the hub cover 70 is formed with a partition wall 72 that constitutes a part of the recess 71 and partitions the hub through-hole 32 b adjacent in the circumferential direction.

  According to such a configuration, the recirculation air flow RA (not shown in FIG. 10) that has flowed out of the electric motor 10 (see FIG. 2) into the recess 71 through the yoke through hole 22a (see FIG. 2) and the hub through hole 32b. 4) is rectified by the concave portion 71 into an air flow toward the radially outer side. Thereby, the effect similar to the effect of (1) and (2) of 1st Embodiment is acquired.

  In addition, in FIG. 10, although the structure which has the six hub through-holes 32b was shown as an example, the number of the hub through-holes 32b is not restricted to this, You may be 5 or less or 7 or more. The number of recesses 71 is set according to the number of hub through holes 32b.

  In the above modification, the partition wall 72 may be omitted from the hub cover 70. In this case, the concave portion 71 is formed in an annular shape whose outer side in the radial direction opens at the outer peripheral portion of the hub cover 70.

In the first embodiment, for example, the inclined cover portion 52 may be omitted from the hub cover 50 as in the hub cover 70 of FIG.
In the first embodiment, the inclined cover portion 52 of the hub cover 50 may be parallel to the inclined portion 33 of the hub 31.

In the first embodiment, the inclined cover portion 52 of the hub cover 50 may be extended so as to cover the outer peripheral portion of the inclined portion 33 of the hub 31.
In the first embodiment, instead of fixing the rotor yoke 20 and the impeller 30 with the screw 36, the rotor yoke 20 and the impeller 30 may be integrally formed by insert molding.

  In the second embodiment, as shown in FIG. 11, the through hole cover 60 of the impeller 30 includes a peripheral wall 65 formed on the front side in the rotation direction RD of the through hole cover 60 and a front in the rotation direction RD. And a rectifying and tilting portion 66 extending so as to tilt toward the yoke cover portion 32. The rectifying inclined portion 66 covers the entire hub through hole 32b from the lower side in the axial direction. According to this configuration, since the air flow that passes through the through hole cover 60 in the circumferential direction flows along the rectifying inclined portion 66, the generation of turbulent flow such as vortex is suppressed in front of the rotation direction RD of the through hole cover 60. Is done. The rectifying and tilting portion 66 may be configured to extend toward the yoke cover portion 32 toward the rear in the rotation direction RD.

  -In the said 2nd Embodiment, as shown in FIG. 12, the through-hole cover 60 of the impeller 30 may open to the front side of the rotation direction RD in the circumferential direction. The through-hole cover 60 includes a rectifying and inclined portion 67 that extends toward the yoke cover portion 32 toward the front in the rotational direction RD. The rectifying inclined portion 67 covers the entire hub through hole 32b from the lower side in the axial direction. According to this configuration, since the airflow that passes through the through hole cover 60 in the circumferential direction flows along the rectifying inclined portion 67, the generation of turbulent flow such as vortex is suppressed in front of the rotation direction RD of the through hole cover 60. Is done.

  In the second embodiment, the rear wall 61 may be formed as a flat inclined portion that is inclined toward the yoke cover portion 32 toward the rear in the rotational direction RD. Alternatively, the front wall portion 62 may be formed as a flat inclined portion that is inclined toward the yoke cover portion 32 toward the front in the rotational direction RD.

In the second embodiment, at least one of the rear wall portion 61 and the front wall portion 62 may be omitted.
-In the said 2nd Embodiment and the modification of the said 2nd Embodiment, even if the through-hole cover 60 is separately formed with the hub 31, it may be the structure by which the through-hole cover 60 is assembled | attached to the hub 31. Good.

In each of the above embodiments, the boss 16 fixed to the shaft 15 may be omitted, and the shaft 15 and the rotor yoke 20 may be directly fixed.
In each of the above embodiments, the number of yoke through holes 22a of the rotor yoke 20 and the number of hub through holes 32b of the hub 31 can be arbitrarily set. For example, the number of yoke through holes 22a and the number of hub through holes 32b may be one, two, or four or more. Further, the number of yoke through holes 22a and the number of hub through holes 32b may be different from each other. In short, it suffices if there is at least one location where the yoke through hole 22a and the hub through hole 32b communicate with each other. In the second embodiment and the modification of the second embodiment, the number of through hole covers 60 is set according to the number of hub through holes 32b communicating with the yoke through holes 22a.

In each of the above embodiments, a gap may be formed between the stator cover portion 22 of the rotor yoke 20 and the yoke cover portion 32 of the hub 31 in the axial direction.
In each of the above embodiments, another annular plate member may be sandwiched between the yoke cover portion 32 and the stator cover portion 22 in the axial direction. When this plate member is comprised by elastic members, such as rubber | gum, propagation of the vibration between the impeller 30 and the electric motor 10 can be suppressed. The plate member is formed with a hole through which the screw 36 or the like passes.

  In each of the above embodiments, the air conditioner to which the present blower is applied is a ceiling-embedded air conditioner, but may be another type of air conditioner. Examples of other types of air conditioners include various air conditioners such as a ceiling-suspended air conditioner, a wall-mounted air conditioner, a trunk-type outdoor unit, and a box-type outdoor type outdoor unit.

  DESCRIPTION OF SYMBOLS 3 ... Blower, 10 ... Electric motor, 14 ... Coil, 15 ... Shaft (rotating shaft), 17 ... Permanent magnet, 20 ... Rotor yoke, 22a ... Yoke through-hole, 30 ... Impeller, 31 ... Hub, 32b ... Hub through-hole , 33 ... inclined part, 34 ... blade, 50 ... hub cover (rectifying mechanism), 51 ... cover part, 52 ... inclined cover part, 60 ... through hole cover (rectifying mechanism), 61 ... rear wall part (rectifying inclined part), 62 ... Front wall portion (rectifying inclined portion), 66 ... Rectifying inclined portion, 67 ... Rectifying inclined portion, 70 ... Hub cover, MA ... Suction main flow, RA ... Recirculating air flow, RD ... Rotating direction.

Claims (5)

A coil (14) that generates a magnetic field, and a cup-shaped rotor yoke (20) that rotates about a rotating shaft (15) and covers one of the coils (14) in the axial direction and the outside of the coil (14) in the radial direction. And an outer rotor type electric motor (10) including a permanent magnet (17) held by the rotor yoke (20) in a state of facing the outer side of the coil (14) with a gap in the radial direction. ,
An impeller having a hub (31) covering the rotor yoke (20) in the axial direction and a plurality of blades (34) fixed to the hub (31) and rotating integrally with the rotor yoke (20). (30) and a blower (3) comprising:
The rotor yoke (20) is formed with a yoke through hole (22a) penetrating in the axial direction.
The hub (31) is formed with a hub through hole (32b) penetrating in the axial direction so as to communicate with the yoke through hole (22a).
A part of the air flow generated by the rotation of the impeller (30) passes through the coil (14) in the axial direction, and passes through the yoke through hole (22a) and the hub through hole (32b) in this order. Forming a circulating airflow (RA),
The hub (31) has a rectifying mechanism (50, 60) that rectifies the recirculated air flow (RA) that has passed through the hub through hole (32b) into an air flow toward the blade (34). Blower. The straightening mechanism (50) is a hub cover (50) attached to the opposite side of the rotor yoke (20) in the axial direction with respect to the hub (31),
The blower according to claim 1, wherein the hub cover (50) has a cover portion (51) facing the hub (31) with a gap in the axial direction. The hub (31) has an inclined portion (33) that is inclined toward the outer side in the radial direction,
The blower according to claim 2, wherein the hub cover (50) has an inclined cover portion (52) that covers at least the radially inner portion of the inclined portion (33). The blower according to claim 1, wherein the rectifying mechanism (60) is formed integrally with the hub (31). The blower (3) is such that the rotation of the impeller (30) is limited to one direction,
The rectifying mechanism (60) covers at least a part of the hub through-hole (32b) from the side opposite to the rotor yoke (20) in the axial direction, and also rotates in the rotational direction (RD) of the impeller (30). The blower according to claim 4, further comprising a rectifying and inclined portion (61, 62, 66, 67) inclined toward the hub (31) toward the front or rear.