Centrifugal fans and rotating motors

Abstract

A centrifugal fan and a rotary motor increase the air volume in the axial direction of the centrifugal fan. The centrifugal fan (1) is composed of a main plate (2) which is annularly arranged around a rotating shaft and has a plurality of plate-shaped blades (4) formed in a range with increasing radius from the front to the rear in the rotating direction. The blades (4) are erected from an arm-shaped plate (3) formed by protruding from the outer diameter side of the plane portion of the main plate (2), and at least one of the plurality of blades (4) has a curved portion (4c) in a part of the face portion constituting the blade (4). The region of the blade (4) provided with the curved portion (4c) is formed in a shape that tilts forward in the rotating direction.

Description

Technical Field

[0001] The present application relates to a centrifugal fan and a rotating electric machine. Background Art

[0002] Centrifugal fans are used as components of rotating electrical machines such as vehicle-mounted alternators. In conventional centrifugal fans, various blade shapes have been designed to improve air volume characteristics and reduce noise.

[0003] For example, an example is disclosed in which a blade of a cooling fan used as an AC generator is formed into a shape obtained by bending a metal plate so as to have a predetermined angle with respect to a main plate (for example, refer to Patent Document 1).

[0004] Furthermore, it is disclosed that support columns of a casing that accommodates an impeller of a conventional centrifugal fan are arranged at different intervals in the circumferential direction to reduce noise (for example, refer to Patent Document 2).

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Laid-Open No. 9-154256

[0008] Patent Document 2: Japanese Patent No. 5727833

[0009] The cooling fan blade disclosed in Patent Document 1 has a blade shape in which the end of the main plate is bent at a predetermined angle. Therefore, although the air volume in the axial direction is increased, the overall air volume and the air volume in the centrifugal direction may be limited.

[0010] Furthermore, in the centrifugal fan disclosed in Patent Document 2, noise can be reduced as an effect of deformation of the casing, but a plurality of blades have the same shape, and it is not shown that the air volume characteristics can be improved by deformation of the blade shape. Summary of the invention

[0011] The present application is made to solve the technical problems mentioned above, and its purpose is to obtain a centrifugal fan that can adjust the air volume characteristics by deforming the blade shape to improve the cooling performance, and a rotating motor including the centrifugal fan.

[0012] The centrifugal fan of the present application includes a main board, which is annularly arranged around a rotating shaft and has a plurality of plate-shaped blades formed in a range with a radius increasing from the front toward the rear in the rotation direction, the blades are arranged upright from the planar portion of the main board, at least one of the plurality of blades has a curved portion in a part of the face portion constituting the blade, and the area of ​​the blade where the curved portion is provided is a shape tilted forward in the rotation direction.

[0013] In addition, the rotating motor of the present application is a rotating motor in which the centrifugal fan is installed at one end of the rotor, and the planar portion of the main board is configured at the axial end of the excitation core constituting the rotor so that the blade is located on the outside, and the curved portion of the blade is configured to overlap axially with the outer edge area of ​​the gap portion between the claw-shaped magnetic poles constituting the excitation core.

[0014] According to the centrifugal fan of the present application, since the axial air volume can be increased by providing a curved portion on the blade and setting a part of the blade to a shape tilted forward in the rotation direction, the air volume in the axial and centrifugal directions of the blade can be adjusted, thereby improving the cooling performance.

[0015] Furthermore, according to the rotating electrical machine of the present application, by installing the centrifugal fan on the rotor, the amount of air delivered in the axial direction of the rotor can be increased, thereby improving the cooling performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a perspective view of the centrifugal fan according to the first embodiment.

[0017] Figure 2 This is a characteristic diagram comparing the performance of the centrifugal fan according to the first embodiment with that of a comparative example.

[0018] Figure 3 This is an enlarged view of a main part of the centrifugal fan of the second embodiment.

[0019] Figure 4 It is a cross-sectional view of a blade of a centrifugal fan according to a third embodiment.

[0020] Figure 5 It is a cross-sectional view of a blade of a centrifugal fan according to a fourth embodiment.

[0021] Figure 6 This is a perspective view of the main parts of the blades of the centrifugal fan according to the fifth embodiment.

[0022] Figure 7 This is a perspective view of the main parts of the blades of the centrifugal fan according to the fifth embodiment.

[0023] Figure 8 It is a cross-sectional view showing a rotating electrical machine according to a seventh embodiment.

[0024] Fig. 9 It is a side view showing a field core of a rotating electrical machine according to a seventh embodiment.

[0025] (Explanation of symbols)

[0026] 1 centrifugal fan

[0027] 2 Motherboard

[0028] 3 arm plate

[0029] 4 blades

[0030] 4a Front edge

[0031] 4b trailing edge

[0032] 4c bending part

[0033] 4d Upper end of leading edge

[0034] 5 Opening

[0035] 7 Pulley

[0036] 8 rotors

[0037] 9 Stator

[0038] 10 collector ring

[0039] 11 Brush

[0040] 12 Voltage Regulator

[0041] 13. Rectification device

[0042] 17 Brush Holder

[0043] 18 Radiator

[0044] 20 Connectors

[0045] 24 Circuit Boards

[0046] 24a terminal

[0047] 27 Protective cover

[0048] 30 rear side housing

[0049] 31 front shell

[0050] 32 Shell

[0051] 32r shell air inlet outer diameter

[0052] 33 bearings

[0053] 34 Axis

[0054] 81 Field winding

[0055] 82 excitation core

[0056] 91 stator core

[0057] 92 stator winding

[0058] 92a wire

[0059] 100 Rotating Motor DETAILED DESCRIPTION

[0060] Implementation Method 1

[0061] use Figure 1 and Figure 2 , the centrifugal fan 1 according to the first embodiment of the present application is described. Figure 1 The centrifugal fan 1 is a perspective view of a centrifugal fan 1 used in, for example, a vehicle-mounted rotating electrical machine 100 , in which blades 4 are arranged on an axial end surface of a rotor 8 (described later) so as to protrude axially outward. Figure 2 It is a characteristic diagram comparing the performance of the centrifugal fan 1 of the present application and the performance of a comparative example.

[0062] like Figure 1 As shown, the centrifugal fan 1 is mainly composed of a main board 2, which is annularly arranged around a through hole for inserting a shaft 34 (described later) of the rotating electric machine 100. The main board 2 has a plurality of blades 4, and the plurality of blades 4 are formed in a range of increasing radius from the front toward the rear in the rotation direction. The blades 4 are erected from an arm-shaped plate 3 protruding in an arm shape from the outer peripheral side of the planar portion of the main board 2. As described above, the arm-shaped plate 3 is a part of the main board 2, and is arranged in a flat plate shape extending radially outward from the outer peripheral portion of the planar portion of the main board 2. The erection angle of the blades 4 from the planar portion of the main board 2 can be set, for example, vertical (or approximately vertical).

[0063] At least one of the plurality of blades 4 located at the end of the main board 2 has a curved portion 4c at a portion of the face (wing surface) constituting the blade 4, and the region of the blade 4 provided with the curved portion 4c is in a shape tilted forward in the rotation direction. Here, the region of the blade 4 provided with the curved portion 4c is different from other portions of the blade 4, and a local curved surface shape is formed to constitute an inclined surface.

[0064] like Figure 1 As shown, one of the plurality of arm-shaped plates 3 included in the centrifugal fan 1 is provided with an opening 5 that penetrates in the axial direction on the radially inner side of the blade 4 .

[0065] In addition, Figure 1 In the example of , fourteen arm-shaped plates 3 are arranged in the circumferential direction. In addition, a step portion may be formed on the inner periphery of the through hole at the center of the main plate 2.

[0066] like Figure 1 As shown, fourteen arm plates 3 are arranged at varying intervals in the circumferential direction of the plane portion of the main plate 2. The radial dimension of the arm plates 3 is smaller on the front side in the rotation direction Rot and larger on the back (or rear) side in the rotation direction Rot.

[0067] In addition, arm-shaped plates 3 having different distances from the rotation center O to the radial outer edge are mixed among the plurality of arm-shaped plates 3, and the distances of the blades 4 from the rotation center O are also varied. Although the curved portion 4c for increasing the axial air volume is selectively provided on the blade 4, arranging the curved portion 4c on the blade 4 that is close to the rotation center O will more effectively improve the cooling performance.

[0068] like Figure 1 As shown, the blade 4 is formed into a single plate by integrating a trailing edge 4b ​​located at the rear side in the rotation direction (or radially outward) and a leading edge 4a located at the front side in the rotation direction (or radially inward).

[0069] The distance from the rotation center C of the centrifugal fan 1 to the trailing edge 4 b of the blade 4 is greater than the distance from the rotation center O to the leading edge 4 a of the blade 4 .

[0070] Furthermore, the shape of the blade 4 projected onto a plane perpendicular to the axis can be approximated to an arc having a gentle curve formed convex toward the rotation center O with respect to a line connecting the leading edge 4a and the trailing edge 4b.

[0071] Here, in order to reduce the blowing sound generated by the front edge portion 4a when the centrifugal fan 1 rotates, the front edge portion 4a of the blade 4 may be inclined toward the rotation center O or to the rear side in the rotation direction.

[0072] In this way, the centrifugal fan 1 composed of the main board 2 with blades 4 generates an airflow that flows radially outward (centrifugal direction) along the blades 4. Thus, the centrifugal fan 1 converts the airflow toward the central part of the main board 2 into an airflow toward the radial outward. In addition, the shape of the main board 2 is not limited to annular, and no step portion may be provided on the inner periphery. In addition, the central part of the main board 2 may also be in the shape of a bowl-shaped protrusion. In addition, the number of arm-shaped plates 3 is not limited to 14, and may be more than four, or may be an odd number. In addition, the configuration of the plurality of arm-shaped plates 3 may also be equally spaced, and reinforcing ribs may be provided on each arm-shaped plate 3.

[0073] In addition, the shape of the projection of the blade 4 onto the surface perpendicular to the axis may also be a straight line or an S-shaped shape, and the shapes of the blades 4 may also be different. In addition, the blade 4 may not protrude from the outer peripheral end of the arm-shaped plate 3 but protrude from a position close to the center in the plane. In addition, an annular shield may also be configured on the radially outer side of the blade 4.

[0074] In addition, the shape of the opening 5 is not limited to Figure 1In addition to the circle shown, different shapes such as ellipse, polygon, etc. can also be set. In addition, in order to reduce the resistance applied to the airflow through the opening 5 and reduce the flow rate of the air flowing in the axial direction, the edge of the opening 5 can also be formed into a circular shape or a rounded shape.

[0075] In addition, the opening 5 only needs to be arranged in the flat surface of the main plate 2 , and may be arranged in a region other than the arm plate 3 .

[0076] Furthermore, when two adjacent arm-shaped plates 3 are close to each other, the two arm-shaped plates 3 may be integrated, and the opening 5 may be formed in the integrated arm-shaped plate 3 .

[0077] In addition, although Figure 1 2 shows an example in which two openings 5 ​​are provided on the main board 2, but the number of openings 5 ​​can be adjusted, and the number can be one, one can be provided on each arm-shaped plate 3, or one opening can be provided in each arm-shaped plate 3 arranged sequentially in the circumferential direction. In addition, a plurality of openings 5 ​​can be provided on one arm-shaped plate 3, and the shapes of the openings 5 ​​can be made various.

[0078] By increasing the openings 5 ​​and reducing the weight, the centrifugal fan 1 is brought closer to the center of gravity of the centrifugal fan 1 and thus the rotation of the centrifugal fan 1 can be stabilized. In this case, the arrangement, number and size of the openings 5 ​​provided on each arm plate 3 can also be determined in consideration of the circumferential weight balance of the centrifugal fan 1.

[0079] In the centrifugal fan 1 of the present application, the outer side of the blade 4 is a positive pressure surface (the surface on the front side of the rotation direction) for releasing the airflow, and the inner side of the blade 4 is a negative pressure surface (the surface on the rear side of the rotation direction). In addition, the axial dimension (standing height) of the blade 4 is smaller at the leading edge 4a in the rotation direction and larger at the trailing edge 4b, thereby suppressing the collision of wind at the leading edge 4a. That is, Figure 1 As shown in the front edge side upper end portion 4 d of the blade 4 , the amount of axial protrusion of the front edge side upper end portion 4 d from the main plate 2 (arm plate 3 ) is suppressed to be small, so that the wind noise can be reduced compared with other parts of the blade 4 .

[0080] In the centrifugal fan 1 as described above, at least one blade 4 is formed with a curved portion 4c on a portion of the face portion constituting the blade 4, and the region of the blade 4 provided with the curved portion 4c is in a shape tilted forward in the rotation direction. Here, the curved portion 4c refers to, for example, a portion formed on the face portion serving as the positive pressure surface of the blade 4, the curvature radius of which changes along the axial direction. The curved portion 4c is sometimes formed by extending along the face portion of the blade 4 in the radial direction and the axial direction.

[0081] In the example of the first embodiment, the curved portion 4c is arranged behind the rotation direction of the blade 4 or on the outer diameter side of the blade 4, that is, the trailing edge portion 4b. In this case, the curved portion 4c is arranged so that the outer diameter side of the blade 4 is tilted in the rotation direction, and the positive pressure surface of the blade 4 is arranged in a shape in which the radius of curvature increases (the curvature decreases) as it moves from the outer diameter side to the inner diameter side. Thus, the positive pressure surface of the blade 4 can be made to have a concave curve at the trailing edge portion 4b, thereby increasing the airflow flowing in the axial direction.

[0082] In this way, in the area where the blade 4 of the centrifugal fan 1 is provided with the curved portion 4c, a twist is applied to the face of the blade 4, so that the area of ​​the blade 4 projected onto the surface perpendicular to the axis can be increased, thereby increasing the axial air volume. Therefore, by adjusting the curvature and the formation range of the curved portion 4c, the axial and radial air volumes of the centrifugal fan 1 can be balanced, thereby improving the cooling performance.

[0083] In addition, although Figure 1 In the example, the curved portion 4c is provided in a space between the blades 4 arranged in the circumferential direction, but the curved portion 4c may be provided on only one blade 4, or on a plurality of blades 4 with the curved portion 4c being provided at varying intervals, or on each blade 4.

[0084] Figure 2 The bar graph shows the centrifugal fan of the present invention not being applied and the blade 4 not being provided with the curved portion 4c, ... Figure 2 The present application) is a characteristic diagram showing the results of comparing the cooling air volume in the overall, centrifugal and axial directions with reference to Comparative Example 1. The overall air volume represents the sum of the air volumes in the centrifugal and axial directions.

[0085] Figure 2 The following is shown: by applying the centrifugal fan 1 of the present application, the axial air volume can be increased without reducing the air volume in the centrifugal direction, compared with Comparative Examples 1 and 2, thereby increasing the overall cooling air volume.

[0086] Implementation Method 2

[0087] Although the example in which the curved portion 4c is provided on the trailing edge portion 4b side of the blade 4 is shown in the above-mentioned first embodiment, in the second embodiment, the curved portion 4c is provided on the trailing edge portion 4b side of the blade 4. Figure 3 The case where the curved portion 4c is provided at a position closer to the inner diameter side than the trailing edge portion 4b of the blade 4 will be described. Figure 3, the distance between the rotation center O and the leading edge 4a of the blade 4 (the radial position is shown as point A) is set as RA, the distance between the rotation center O and the trailing edge 4b ​​of the blade 4 (the radial position is shown as point B) is set as RB, and the distance between point C on the face between the leading edge 4a and the trailing edge 4b ​​of the blade 4 and the rotation center O is set as RC (RA<RC<RB). Point C shows the middle position of the edge of the blade 4 in the rotation direction and the radial direction.

[0088] At this time, at least one blade 4 is provided with a curved portion 4c between RA and RC, that is, at a position closer to the inner diameter side than the trailing edge portion 4b of the blade 4, and a part of the blade 4 is formed into a curved shape. The radial position of the curved portion 4c is shown as point D. The distance from point D to the rotation center O is shown as RD. The curved portion 4c is provided at the position indicated by point D of the blade 4, so that the relationship of RD<RC<RB is formed.

[0089] Even when a curved portion 4c is provided near the inner diameter of the blade 4, the airflow in the axial direction can be increased compared to a case where the curved portion 4c is not provided. In addition, by adopting the above-mentioned structure, the blowing sound generated at the leading edge 4a of the blade 4 can be suppressed.

[0090] In addition, although Figure 3 In the example, the radius (RB) of the trailing edge portion 4b of the blade 4 provided with the curved portion 4c is smaller than the outer diameter RO of the centrifugal fan 1, but there is also a case where the curved portion 4c is formed so that the size of the blade 4 is the outer diameter RO. In this case, the relationship of RD<RC<RO is formed, which can reduce the gust of wind generated by the airflow and increase the axial airflow.

[0091] Implementation Method 3

[0092] In the first and second embodiments, the radially curved portion 4c of the blade 4 is arranged on the trailing edge 4b ​​side and closer to the inner diameter side than the trailing edge 4b. Figure 4 An example of arrangement of the curved portion 4 c of the blade 4 in the axial direction will be described. Figure 4 Equivalent to Figure 3 The cross-sectional view of the blade 4 at point C on the face of the blade 4 along the axial circumferential direction. The inclined surface of the blade 4 provided with the curved portion 4c is set in a shape in which the radius of curvature decreases (the curvature gradually increases) as it moves from the end (suction side) of the blade 4 toward the plane portion of the main board 2 along the axial direction. The radius of curvature of the suction side (L2) of the end of the blade 4 is a value larger than the radius of curvature of the plane portion side (L1) of the main board 2.

[0093] In this way, by increasing the curvature at a position closer to the flat surface of the main plate 2 than the end of the blade 4, the flow of the cooling air can be adjusted, thereby improving the cooling performance.

[0094] Implementation Method 4

[0095] In the third embodiment, the blade 4 is provided with a curved portion 4c, and the blade shape is formed so that the curvature radius decreases as it moves from the suction side toward the flat portion side of the main plate 2 in the axial direction. Figure 5 The following describes a case where the blade shape is formed so that the curvature radius increases from the suction side toward the flat portion side of the main plate 2 in the axial direction, which is opposite to the third embodiment. Figure 5 As shown in the axial circumferential cross-sectional view of the blade 4, when the blade is curved into a blade shape with a curvature radius gradually increasing from the suction side (L2) toward the plane side (L1) of the main board 2, the flow of cooling air can be adjusted and the cooling performance can be improved.

[0096] In addition, Figure 5 The example of FIG. 1 shows a state in which an inclined surface with a large curvature is provided at a position closer to the depth side, that is, the inner diameter side than the cross-sectional portion of the blade 4.

[0097] Implementation Method 5

[0098] also, Figure 6 , Figure 7 An example of the blade shape of the centrifugal fan 1 according to the fifth embodiment of the present application is shown. Figure 6 This is a perspective view of the main parts of the blade 4 of the centrifugal fan 1, in which the negative pressure surface of the blade 4 is shown on the near front side, and shows cross sections along the radial direction at two locations of the blade 4, in front and behind the rotation direction. Figure 7 This is a perspective view of the main parts of the blade 4 of the centrifugal fan 1, in which the positive pressure surface of the blade 4 is shown on the near side, and shows cross sections along the circumferential direction at two locations of the blade 4, front and rear in the rotation direction. Figure 7 In the figure, the section near the leading edge 4a is marked with a mark (L2_F) indicating the suction side and a mark (L1_F) indicating the plane side of the main board 2, and the section near the trailing edge 4b ​​is marked with a mark (L2_R) indicating the suction side and a mark (L1_R) indicating the plane side of the main board 2. In both cases, the curved degree of the blade 4 is greater on the side near the leading edge 4a, and the curved degree becomes smaller as it approaches the trailing edge 4b, and a curved portion 4c is provided in a wide range from the leading edge 4a to the trailing edge 4b ​​on the face of the blade 4.

[0099] like Figure 6 , Figure 7As shown, the blade 4 is set in the following shape: in the area where the curved portion 4c is provided, from the front to the rear in the rotation direction, the position where the axial curvature radius of the blade 4 is the smallest is offset in the direction approaching the arm plate 3 (the flat portion of the main plate 2) from the axial suction side of the blade 4. In addition, although the offset direction of the position where the axial curvature radius is the smallest is indicated by an arrow as the curved portion 4c, the portion indicated by the arrow shows the position where the axial curvature radius is the smallest, and of course, a curved shape is formed on the face portion located around the arrow.

[0100] In this way, a curved portion 4c is provided on the blade 4 from the front to the rear in the rotation direction, and the blade 4 is formed into a shape in which the position with the smallest radius of curvature in the axial direction approaches the planar portion of the main board 2 from the front to the rear in the rotation direction (as the distance from the rotation center O increases), thereby obtaining a blade shape with a changed curvature in the radial and axial directions, and improving the rectification performance of the centrifugal fan 1.

[0101] Implementation Method 6

[0102] As described above, the centrifugal fan 1 has a structure in which a plurality of blades 4 are arranged in the circumferential direction. However, in the sixth embodiment, it will be described which blade 4 among the plurality of blades 4 is more effective in improving the cooling performance by providing the curved portion 4 c.

[0103] The amount of air borne by the blade 4 of the centrifugal fan 1 tends to increase as the distance between the blade 4 located in front of the rotation direction of the blade 4 increases. Therefore, when the distance between the ends of the two adjacent blades 4 in the rotation direction of the centrifugal fan 1 is the largest, or the distance is greater than a specified value and the amount of air colliding with the positive pressure surface of the blade 4 is large, the amount of air in the axial direction can be effectively increased by providing a curved portion 4c on the blade 4 located in the rear of the rotation direction.

[0104] Implementation Method 7

[0105] The centrifugal fan 1 disclosed in the above-mentioned first to sixth embodiments can be applied to a rotating electric machine 100. For example, it can also be mounted on a rotor 8 of a rotating electric machine 100 such as an on-vehicle AC generator, a motor, or an on-vehicle drive device for use. Here, as an example, a vehicle AC generator is shown as a rotating electric machine 100 to which the centrifugal fan 1 of the present application is applied. Figure 8 This is a cross-sectional view of the rotating electrical machine 100 as viewed from the side.

[0106] Figure 8In the embodiment, the rotating electric machine 100 has a housing 32, which is composed of a front housing 31 and a rear housing 30 made of aluminum alloy, each of which is roughly bowl-shaped. In addition, the rotating electric machine 100 has a shaft 34, which is rotatably supported by the housing 32 through a pair of bearings 33, and a pulley 7, which is fixed to the end of the shaft 34 protruding on the front side of the housing 32. The front bearing 33 is supported by the front housing 31, and the rear bearing 33 is supported by the rear housing 30.

[0107] In addition, the rotating electric machine 100 has a rotor 8 and a stator 9, wherein the rotor 8 is fixed to the shaft 34 and arranged in the housing 32, and rotates integrally with the shaft 34, and the stator 9 is fixed to the housing 32 in a manner surrounding the rotor 8. In addition, the rotating electric machine 100 has: a pair of slip rings 10, the pair of slip rings 10 are fixed to the protruding portion of the shaft 34 protruding on the rear side of the housing 32, and supply current to the rotor 8; a pair of brushes 11, the pair of brushes 11 are accommodated in the brush holder 17, and slide on the surface of each slip ring 10; and a voltage regulator 12, which is arranged adjacent to the pair of brushes 11 and adjusts the magnitude of the AC voltage generated by the stator 9.

[0108] In addition, the rotating motor 100 has: a rectifier 13, which converts the AC voltage generated by the stator 9 into a DC voltage; a connector 20, which transmits signals between the voltage regulator 12 and an external device; and a protective cover 27, which is installed on the rear shell 30 to cover the voltage regulator 12, the rectifier 13 and the brush holder 17.

[0109] The rotor 8 is a Lundell-type rotor having an excitation winding 81 and an excitation core 82, wherein the excitation winding 81 generates magnetic flux by allowing an excitation current to flow, and the excitation core 82 is arranged to be fixed to the shaft 34 passing through the axial center position and covering the excitation winding 81, and forming magnetic poles through the magnetic flux generated by the excitation winding 81.

[0110] The centrifugal fan 1 according to the first embodiment of the present application is arranged on the mounting surface of the rotor 8 on the pulley 7 side or on the mounting surface on the opposite side to the pulley 7 .

[0111] The stator 9 is coaxially arranged on the outer periphery of the rotor 8. The stator 9 includes: a cylindrical stator core 91; a stator winding 92, which is mounted on the stator core 91 and generates alternating current according to the change of magnetic flux from the excitation winding 81 as the rotor 8 rotates. The stator core 91 is clamped from both sides of the axial direction between the front housing 31 and the rear housing 30. The wire 92a of the stator winding 92 is led out from the rear housing 30 and connected to the terminal 24a of the circuit board 24. Thus, the rectifier 13 is electrically connected to the stator winding 92. The rectifier 13 includes a heat sink 18 on which a plurality of rectifier elements are mounted and a circuit board 24.

[0112] In the rotating electric machine 100 constructed as described above, the rotational torque of the engine (not shown) is transmitted to the shaft 34 through the pulley 7, so that the rotor 8 rotates. At this time, the current is supplied to the excitation winding 81 of the rotor 8 through the brush 11 and the slip ring 10, thereby generating a magnetic flux. Through the above-mentioned magnetic flux, N poles and S poles are alternately formed in the circumferential direction on a plurality of claw-shaped magnetic poles arranged on the outer periphery of the excitation core 82. As a result, a rotating magnetic field is provided to the stator winding 92 of the stator 9, thereby generating an electromotive force of alternating current in the stator winding 92. The electromotive force of the above-mentioned alternating current is supplied to the rectifier 13 through the conductor 92a, thereby being rectified in the rectifier 13, and the magnitude of the electromotive force of the alternating current is adjusted by the voltage regulator 12, and then supplied to the battery and the vehicle-mounted electrical installation parts.

[0113] Here, as the rotor 8 rotates, the centrifugal fan 1 fixed to the pulley 7 side of the field core 82 rotates. As the centrifugal fan 1 rotates, external air is sucked into the interior of the housing 32 from the opening formed in the front housing 31. The external air sucked into the interior of the housing 32 flows axially in the front housing 31 and reaches the field core 82, and the front coil ends of the field winding 81 and the stator winding 92 are cooled.

[0114] Fig. 9 The figure shows the mounting surface G side of the centrifugal fan 1 of the field core 82 of the rotating electrical machine 100. The mounting surface G of the centrifugal fan 1 is provided on the side opposite to the side from which eight claw-shaped magnetic poles provided on the field core 82 extend. Fig. 9 The area F indicated by the oblique lines in the middle indicates the range in which cooling air can flow when the field winding 81 is effectively cooled, and corresponds to the area obtained by projecting the gaps (or gap portions) between the claw-shaped magnetic poles provided in the field core 82 onto the centrifugal fan mounting surface G.

[0115] When the centrifugal fan 1 is mounted on the mounting surface G, the overlap between the curved portion 4c and the region F is increased in the axial direction, thereby increasing the axial airflow. On the other hand, when the curved portion 4c overlaps the mounting surface G in the axial direction, the airflow collides with the excitation core 82, increasing the blowing sound.

[0116] Therefore, by arranging the bent portion 4 c of the centrifugal fan 1 at a portion overlapping the region F when projected onto the mounting surface G, the airflow flowing in the axial direction can be increased without increasing the generated blowing sound, thereby effectively cooling the field winding 81 .

[0117] Therefore, it is possible to improve the cooling capacity of the field winding 81 of the field core 82 and the coil ends of the stator winding 92. As a result, it is possible to increase the power generation output of the vehicle-mounted rotating electrical machine.

[0118] At this time, by arranging the arm-shaped plate 3 of the centrifugal fan 1 to overlap the mounting surface G of the field core 82 and arranging the rising portion of the blade 4 to overlap the outer edge of the claw-shaped magnetic pole of the field core 82, it is possible to ensure a wide opening for conveying cooling air in the axial direction. Therefore, the flat portion of the main plate 2 of the centrifugal fan 1 is arranged at the axial end of the field core 82 of the rotor 8 so that the blade 4 faces outward, and further, the curved portion 4c of the blade 4 is arranged to overlap the outer edge area of ​​the gap between the claw-shaped magnetic poles constituting the field core 82 in the axial direction, more specifically, the outer edge area of ​​the V-shaped portion in the rotation direction rearward, thereby effectively increasing the axial air volume while suppressing the blowing sound.

[0119] In addition, if Fig. 9 As shown, for example, when the maximum outer diameter of the mounting surface G of the centrifugal fan 1 is set to R1, the curved portion 4c of the centrifugal fan 1 is set within the radius R1 from the rotation center O (the inner diameter side of the maximum outer diameter portion), so that the amount of air flowing in the axial direction can be more effectively increased, and the excitation winding 81 can be effectively cooled. The area outside the radius R1 is a space required for the exhaust gas to flow after cooling the excitation winding 81. Therefore, in order to blow out the air that has become heated by cooling the excitation winding 81 in the axial direction, it is necessary to arrange the curved portion 4c of the centrifugal fan 1 in an area that does not hinder the exhaust gas flow and is closer to the inner diameter side than R1. By arranging the curved portion 4c in an area that is closer to the inner diameter side than R1, the cooling of the excitation winding 81 can be improved while suppressing the sound of wind blowing. In addition, in Fig. 9 In FIG. 8 , the minimum outer diameter of the mounting surface G is represented as R2, and the maximum outer diameter of the field core 82 is represented as R0.

[0120] In addition, Fig. 9The maximum opening radius of the air inlet hole of the shell 32 is shown as the shell air inlet outer diameter 32r. In the axial direction, the edge of the air inlet hole of the shell 32 overlaps with the circle with the shell air inlet outer diameter 32r as the radius. In the plane perpendicular to the axis, the curved portion 4c of the centrifugal fan 1 is arranged at a position closer to the inside than the edge of the air inlet hole of the shell 32, that is, arranged on the inside of a circle with a radius smaller than the shell air inlet outer diameter 32r, so that the turbulence of the air flow generated at the air inlet hole of the shell 32 can be suppressed to a smaller extent, the air volume in the axial direction can be effectively increased while suppressing the sound of blowing wind, and the excitation winding 81 can be cooled more effectively.

[0121] Although the present disclosure describes exemplary embodiments, various features, aspects, and functions described in the embodiments are not limited to being applied to specific embodiments, and can be applied to the embodiments alone or in various combinations.

[0122] Therefore, numerous modifications not shown in the examples are conceivable within the technical scope disclosed in the present specification, including, for example, modifying at least one component, adding at least one component, or omitting at least one component.

Claims

1. A centrifugal fan, characterized in that: The centrifugal fan includes a main plate which is annularly arranged around a rotating shaft and has a plurality of plate-shaped blades formed in a range with increasing radius from the front to the rear in the rotating direction. The blades are arranged upright from the plane portion of the main board. At least one of the plurality of blades has a curved portion, the curved portion is formed at a portion of a face portion serving as a positive pressure surface of the blade, and a radius of curvature of the curved portion changes along an axial direction. The region of the blade where the curved portion is provided has a shape that is tilted forward in the rotation direction.

2. The centrifugal fan according to claim 1, wherein: The curved portion is provided at a trailing edge portion of the blade located on the outer diameter side.

3. The centrifugal fan according to claim 1, wherein: The curved portion is provided at a position closer to the inner diameter side than a trailing edge portion located on the outer diameter side of the blade.

4. The centrifugal fan according to any one of claims 1 to 3, characterized in that: The region of the blade where the curved portion is provided is provided in a shape in which a radius of curvature decreases as it moves from an end portion of the blade toward a flat surface portion of the main plate in the axial direction.

5. The centrifugal fan according to any one of claims 1 to 3, characterized in that: The region of the blade where the curved portion is provided is provided in a shape in which a radius of curvature increases from an end portion of the blade toward a flat surface portion of the main plate in an axial direction.

6. The centrifugal fan according to any one of claims 1 to 3, characterized in that: The curved portion of the blade is arranged from the front to the rear in the rotation direction, The blade is formed in a shape in which a position where the radius of curvature in the axial direction is the smallest approaches the flat surface portion of the main plate as it moves from the front toward the rear in the rotation direction of the blade.

7. The centrifugal fan according to any one of claims 1 to 3, characterized in that: When the interval between the ends of the two adjacent blades at the front in the rotation direction is the largest, the curved portion is provided on the blade located at the rear in the rotation direction.

8. A rotating electric machine, wherein the centrifugal fan according to any one of claims 1 to 7 is mounted on one end of a rotor, wherein: The flat surface of the main plate is arranged at an axial end of the field core constituting the rotor so that the blades are located outside. The curved portion of the blade is arranged so as to overlap with an outer edge region of a gap portion between claw-shaped magnetic poles constituting the field core in the axial direction.

9. The rotating electrical machine according to claim 8, characterized in that The curved portion of the blade is arranged at a position closer to the inner diameter side than a maximum outer diameter portion of the mounting surface of the field core.

10. The rotating electrical machine according to claim 8 or 9, characterized in that: The curved portion of the blade is provided at a position closer to the inner diameter side than an edge portion of an air inlet hole of a housing surrounding the centrifugal fan.

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