JP2019056369A - Serial axial flow fan - Google Patents

Abstract

To improve ventilation efficiency of a serial axial flow fan.SOLUTION: A serial axial flow ran 100 includes a first axial flow fan 1, a second axial flow fan 2 and a current plate 3. A plurality of hollow cells of a current plate are partitioned by a lattice-shaped partitioning wall, penetrated in an axial direction, and uniformly two-dimensionally arranged to an outer edge portion. An axial lower end portion of a first housing 13 of the first axial flow fan and an axial upper end portion of a second housing 23 are directly connected, and the current plate is disposed on a connection portion of both. An axial lower end portion of a first cylindrical portion of the first housing is axially opposed to an axial upper end portion of a second cylindrical portion of the second housing through the current plate. An axial end face of at least one of the cylindrical portions of the axial lower end face of the first cylindrical portion and an axial upper end face of the second cylindrical portion is provided with a recessed portion recessed to a side opposite to the axial connection portion. A lead wire of at least one of the first axial flow fan and the second axial flow fan is housed in the recessed portion. At least a part of the recessed portion is axially overlapped to a part of the current plate.SELECTED DRAWING: Figure 3

Description

  The present disclosure relates to a series axial fan.

  Conventionally, a series axial fan in which two axial fans are connected in the axial direction to increase the air flow rate is known. In the serial axial fan, the airflow sent from the upstream axial fan that sucks the air outside the serial axial fan is sucked into the downstream axial fan. The airflow whose flow velocity is increased by the subsequent axial fan is sent out of the axial fan from the downstream axial fan. Here, in addition to the axial component, the flow of the airflow sent from the upstream axial fan has the same swirl component as the impeller rotational direction. However, it is difficult for the swirl component of the airflow to flow in the axial direction by the subsequent axial fan.

  Therefore, for example, in the unit type fan disclosed in Japanese Patent Application Laid-Open No. 2003-56498, by disposing the static blade fan frame structure between the two heat dissipating fans, the interference between the two heat dissipating fans is suppressed and the heat dissipating is performed. Increase the air volume and pressure of the airflow generated when the fan is operating.

  In Chinese Patent Application No. 20121246347, a fan casing is attached to the exhaust side of an axial fan. In the fan casing, a convex portion having a honeycomb structure is provided, and a plate-like frame screwed to the axial fan is spread from the outer surface of the convex portion in a direction perpendicular to the axial direction. The convex portion having the honeycomb structure concentrates the airflow more by guiding the airflow sent from the axial fan.

JP 2003-56498 A Chinese Patent Application No. 20121246347

  By the way, in order to draw out the lead wire extended from a motor part in the connection part of two axial flow fans, the recessed part dented in an axial direction from a connection part may be provided in the housing of an axial flow fan. In this case, a part of the airflow sent from the upstream axial fan tends to flow outside the serial axial fan through the recess. Therefore, turbulent flow is likely to occur near the recess. Generation | occurrence | production of such a turbulent flow influences the ventilation efficiency of a serial axial fan.

  An object of this indication is to further improve the ventilation efficiency of a serial axial fan.

  An exemplary series axial fan of the present disclosure includes a first axial fan, a second axial fan connected in series with the first axial fan, and a partition wall that is partitioned by a lattice-like partition and is axially arranged. And a rectifying plate in which a plurality of hollow cells passing therethrough are uniformly two-dimensionally arranged to the outer edge. The first axial fan includes a first impeller having a first blade that is rotatable about a central axis extending in a vertical direction, and a first motor unit that drives the first impeller to rotate the first blade. And a first housing having a cylindrical shape extending in the axial direction and having a first cylindrical portion that accommodates the first impeller and the first motor portion, and a first lead wire extending from the first motor portion. . The second axial fan includes a second impeller having second blades rotatable about the central axis, a second motor unit that drives the second impeller to rotate the second blades, and a shaft A second housing having a cylindrical shape extending in a direction and having a second cylindrical portion that accommodates the second impeller and the second motor portion; and a second lead wire extending from the second motor portion. An axial lower end portion of the first housing and an axial upper end portion of the second housing are directly connected. The rectifying plate is provided at a connection portion between the first housing and the second housing. The lower end portion in the axial direction of the first cylindrical portion is opposed to the upper end portion in the axial direction of the second cylindrical portion in the axial direction via the current plate. On the axial end surface of at least one of the axial lower end surface of the first cylindrical portion and the axial upper end surface of the second cylindrical portion, there is a recess that is recessed on the opposite side to the connecting portion in the axial direction. Provided. At least one of the first lead wire and the second lead wire is received in the recess. At least a part of the recess overlaps a part of the current plate in the axial direction.

  According to the exemplary series axial fan of the present disclosure, the air blowing efficiency of the series axial fan can be further improved.

FIG. 1 is a perspective view illustrating an example of an in-line axial fan according to the embodiment. FIG. 2 is a cross-sectional view of the serial axial fan taken along the one-dot chain line AA of FIG. FIG. 3 is a cross-sectional view of the serial axial fan along the alternate long and short dash line BB in FIG. 2. FIG. 4A is a perspective view showing a first example of a strip-shaped member covering the first opening. FIG. 4B is a perspective view showing a second example of a belt-shaped member covering the first opening. FIG. 4C is a perspective view showing a third example of a band-shaped member covering the first opening. FIG. 5 is a cross-sectional view showing an example of a second recess provided in the second cylinder portion. FIG. 6 is a cross-sectional view illustrating an example of a second leg portion provided in the second cylinder portion. FIG. 7 is a perspective view illustrating an example of a current plate. FIG. 8 is a cross-sectional view of a serial axial fan according to a first modification. FIG. 9 is a perspective view showing an example of an in-line axial fan according to the second modification. FIG. 10 is a perspective view showing an example of an in-line axial fan according to the third modification. FIG. 11 is a cross-sectional view of the serial axial fan taken along the dashed line EE in FIG. FIG. 12 is a cross-sectional view illustrating an example of the second wall portion.

  Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings.

  In the present specification, in the series axial fan 100, a direction parallel to the central axis CA is referred to as an “axial direction”. In the axial direction, a direction from the second axial fan 2 described later to the first axial fan 1 described later is referred to as “axial upper side”, and a direction directed from the first axial fan 1 to the second axial fan 2 is referred to as “axial upper side”. This is called “the lower side in the axial direction”. In each component, the end on the upper side in the axial direction is referred to as “the upper end in the axial direction”, and the position of the upper end in the axial direction in the axial direction is referred to as “the upper end in the axial direction”. Further, the end portion on the lower side in the axial direction is referred to as “the lower end portion in the axial direction”, and the position of the lower end portion in the axial direction in the axial direction is referred to as “the lower end in the axial direction”. In addition, on the surface of each component, the surface facing the upper side in the axial direction is referred to as “axial upper end surface”, and the surface facing the lower side in the axial direction is referred to as “axial lower end surface”. Further, the generic term “the upper end surface in the axial direction” and “the lower end surface in the axial direction” is referred to as “the end surface in the axial direction”.

  A direction orthogonal to the central axis CA is referred to as a “radial direction”, and a rotation direction around the central axis CA is referred to as a “circumferential direction”. In the radial direction, a direction toward the central axis CA is referred to as “radial inner side”, and a direction away from the central axis CA is referred to as “radial outer side”. In each component, an end portion on the radially inner side is referred to as a “radial inner end portion”, and a position of the radial inner end portion in the radial direction is referred to as a “radial inner end”. Further, the end portion on the radially outer side is referred to as a “radial outer end portion”, and the position of the radial outer end portion in the radial direction is referred to as a “radial outer end”. In addition, among the side surfaces of each component, a side surface facing radially inward is referred to as a “radially inner side surface”, and a side surface facing radially outward is referred to as a “radial outer surface”.

  Note that the names such as direction, end, position, and surface described above do not indicate the positional relationship and direction when incorporated in an actual device.

<1. Embodiment>
FIG. 1 is a perspective view showing an example of an in-line axial fan 100 according to the embodiment. FIG. 2 is a cross-sectional view of the serial axial fan 100 taken along the one-dot chain line AA of FIG. 3 is a cross-sectional view of the serial axial fan 100 taken along the one-dot chain line BB in FIG. FIG. 2 shows a cross-sectional structure of the serial axial fan 100 cut along a virtual plane perpendicular to the axial direction. FIG. 3 shows a cross-sectional structure when the serial axial fan 100 is cut along a virtual plane including the central axis CA.

<1-1. Fan motor configuration>
As shown in FIG. 1, the serial axial fan 100 includes a first axial fan 1, a second axial fan 2, and a rectifying plate 3. The serial axial fan 100 is a blower in which a first axial fan 1 at the front stage and a second axial fan 2 at the rear stage are connected in series with the rectifying plate 3 interposed therebetween.

  The serial axial fan 100 includes the first axial fan 1 as described above. The first axial fan 1 includes a first impeller 11, a first motor unit 12, a first housing 13, and a first lead wire 14. The first housing 13 includes a first tube part 131, a first flange part 132, and a first rib 133. Further, the serial axial fan 100 includes the second axial fan 2 as described above. The second axial fan 2 is connected in series with the first axial fan 1. The second axial fan 2 includes a second impeller 21, a second motor unit 22, a second housing 23, and a second lead wire 24. The second housing 23 includes a second cylinder portion 231, a second flange portion 232, and a second rib 233.

  Hereinafter, the first housing 13 and the second housing 23 are collectively referred to as “housings 13 and 23”. Further, the generic name of the first lead wire 14 and the second lead wire 24 is referred to as “lead wires 14, 24”. In addition, the generic name of the first cylinder part 131 and the second cylinder part 231 is referred to as “cylinder parts 131 and 231”. The generic name of the first flange portion 132 and the second flange portion 232 is referred to as “flange portions 132 and 232”. Further, the generic name of the first rib 133 and the second rib 233 is referred to as “ribs 133 and 233”. Description of each component of the 1st axial flow fan 1 and the 2nd axial flow fan 2 is mentioned later.

  The rectifying plate 3 is provided at a connecting portion 100 a between the first housing 13 and the second housing 23. The rectifying plate 3 provided in the connecting portion 100 a between the first housing 13 and the second housing 23 rectifies the airflow sent from the first axial fan 1 to the lower side in the axial direction. The second axial fan 2 sucks the airflow rectified by the rectifying plate 3. The rectified airflow has a small swirling component and easily flows in the axial direction by the second axial fan 2. Thereby, the pressure and the air volume of the airflow sent from the second axial fan 2 are increased. As a result, the amount of air sucked or delivered by the serial axial fan 100 can be increased. Therefore, the blowing efficiency of the serial axial fan 100 can be further improved. The material of the current plate 3 is aluminum in the present embodiment, but is not limited to this example, and may be other metal material, ceramic material, or the like. A more detailed configuration of the current plate 3 will be described later.

<1-2. First axial fan>
Next, each component of the first axial fan 1 will be described with reference to FIGS. 1 to 3.

  The first axial fan 1 has the first impeller 11 as described above. The first impeller 11 has a first blade 111. The first blade 111 is rotatable about a central axis CA that extends in the vertical direction. When the first motor unit 12 drives the first impeller 11, the first blade 111 rotates about the central axis CA. Thus, the first axial fan 1 sucks air from the upper side in the axial direction of the serial axial fan 100 at the upper end in the axial direction of the first axial fan 1. The first axial fan 1 generates an airflow that flows downward in the axial direction, and sends the airflow from the lower end in the axial direction of the first axial fan 1.

  The first axial fan 1 has the first motor unit 12 as described above. The first motor unit 12 drives the first impeller 11 to rotate the first blade 111. The lower end portion in the axial direction of the first motor unit 12 may be in contact with the upper end surface in the axial direction of the rectifying plate 3. Alternatively, the lower end portion in the axial direction of the first motor unit 12 may be opposed to the upper end surface in the axial direction of the rectifying plate 3 in the axial direction with a gap.

  The first axial fan 1 has the first housing 13 as described above. The first housing 13 has the first cylindrical portion 131 as described above. The 1st cylinder part 131 is a cylinder shape extended in an axial direction, and accommodates the 1st impeller 11 and the 1st motor part 12 inside. The lower end portion in the axial direction of the first cylindrical portion 131 is opposed to the upper end portion in the axial direction of the second cylindrical portion 231 in the axial direction via the rectifying plate 3. Moreover, the axial direction lower end part of the 1st cylinder part 131 contact | abuts to the axial direction upper end surface of the baffle plate 3 in this embodiment. By so doing, the airflow can be prevented from flowing in the radial direction at the lower end portion in the axial direction of the first tube portion 131. Therefore, the occurrence of turbulent flow at the lower end in the axial direction of the first tube portion 131 can be prevented. However, the present invention is not limited to this example, and there may be a gap between the first tube portion 131 and the rectifying plate 3 in the axial direction.

  In the present embodiment, the first cylindrical portion 131 is provided with a first concave portion 131a that is recessed on the opposite side of the axially connecting portion 100a on the lower end surface in the axial direction. The first recessed portion 131a is recessed upward in the axial direction at the lower end surface in the axial direction of the first cylindrical portion 131, and penetrates the first cylindrical portion 131 in the radial direction.

  Further, the first housing 13 further includes the first flange portion 132 as described above. The first flange portion 132 extends radially outward from the axial end on the connecting portion 100 a side of the first tube portion 131. In other words, the first flange portion 132 extends radially outward from the lower end portion in the axial direction of the first tube portion 131. Furthermore, a first flat surface portion 132 a and a first leg portion 132 b are provided on the lower end surface in the axial direction of the first flange portion 132. The first flat surface portion 132 a abuts on the axial upper end surface of the rectifying plate 3. The first leg portion 132 b protrudes downward in the axial direction of the first flange portion 132. There are a plurality of first leg portions 132b, which are respectively provided in the circumferential direction. The lower end portion in the axial direction of the first leg portion 132b abuts on the second flange portion 232. Thereby, in the axial direction, a space in which the rectifying plate 3 is accommodated is provided between the first tube portion 131 and the second tube portion 231. The axial length df1 shown in FIG. 3 of the first leg portion 132b is equal to or less than the axial length dc shown in FIG. The axial length df1 of the first leg portion 132b is an axial width between the first flat portion 132a and the lower end portion in the axial direction of the first leg portion 132b. Therefore, the rectifying plate 3 is sandwiched and held between the lower end in the axial direction of the first cylindrical portion 131 and the upper end in the axial direction of the second cylindrical portion 231 in the axial direction. Further, when viewed from the axial direction, the first leg portion 132b is provided on the outer side in the radial direction than the first concave portion 131a.

  The first housing 13 further includes the first rib 133 as described above. The radially inner end of the first rib 133 supports the first motor unit 12. A radially outer end portion of the first rib 133 is connected to the first tube portion 131.

  The first rib 133 is opposed to the axial upper end surface of the rectifying plate 3 in the axial direction with a gap. The minimum axial width of the gap (Wri1 in FIG. 3) is narrower than the width (for example, the width Wc shown in FIG. 7) in the direction perpendicular to the axial direction of the hollow cell 3a of the rectifying plate 3. In this way, by providing a gap narrower than the width in the direction perpendicular to the axial direction of the hollow cell 3a between the first rib 133 and the rectifying plate 3, while maintaining the rectifying effect by the first rib 133, the first It is possible to prevent a decrease in the amount of airflow passing through the hollow cell 3a that overlaps the one rib 133 in the axial direction. This is because, in the axial direction, when there is no gap between the first rib 133 and the rectifying plate 3, the amount of airflow passing through the hollow cell 3a overlapping the first rib 133 in the axial direction is reduced. On the other hand, when the axial width of the gap between the first rib 133 and the rectifying plate 3 is too wide, the effect of rectifying the airflow flowing in the axial direction by the first rib 133 is reduced.

  Further, the axial width Wri1 of the gap between the first rib 133 and the axial upper end surface of the rectifying plate 3 in the radial direction is equal to the gap of the gap between the first rib 133 and the axial upper end surface of the rectifying plate 3 in the radial direction. It is smaller than the axial width Wro1. In this embodiment, as shown in FIG. 3, the axial width Wri1 is smaller than the width Wc between the two sides of the hexagonal hollow cell 3a in the rectifying plate 3. On the other hand, the axial width Wro1 is larger than the width Wc between two sides of the hexagonal hollow cell 3a. The optimum value of the axial width of the gap for improving the air pressure and the air flow and suppressing the occurrence of turbulent flow is different between the radially inner side and the radially outer side of the first rib 133. In particular, the optimum value is influenced by the radially inner side surface of the first cylindrical portion 131 at the radially outer end portion of the first rib 133. Therefore, by making the axial width Wro1 of the gap larger than the width Wc between the two sides of the hollow cell 3a, the pressure-air volume characteristic of the series axial fan 100 can be improved.

  Further, the width dr1 of the portion of the first rib 133 facing the rectifying plate 3 in the axial direction is preferably not more than the width Wc between the two sides of the hexagonal hollow cell 3a. In addition, this site | part is the axial direction lower end part of the 1st rib 133, for example. The width dr1 is, for example, the minimum width in a direction perpendicular to the axial direction of the first rib 133. If it carries out like this, the pressure and air volume of the airflow which flow the baffle plate 3 from the 1st axial flow fan 1 to the 2nd axial flow fan 2 can be improved, and generation | occurrence | production of a turbulent flow can be suppressed.

  In the present embodiment, the first housing 13 is provided with four first openings 13a as shown in FIG. The first opening 13a is provided at the lower end in the axial direction of the first housing 13, and is recessed upward in the axial direction. The first opening 13a penetrates the first housing 13 in the radial direction, and particularly penetrates a part of the first tube part 131 and a part of the first flange part 132 in the radial direction. In the first opening 13 a, the radially outer end surface of the rectifying plate 3 is exposed to the outside of the serial axial fan 100. In addition, the radial direction outer end part of the baffle plate 3 exists in the radial inside rather than the 1st opening part 13a as shown in FIG. 2, or the 1st opening part 13a.

  In addition, it is not limited to the illustration of FIG. 1, The baffle plate 3 does not need to be exposed in the 1st opening part 13a. For example, the serial axial fan 100 may further include a belt-like member 4 provided on the radially outer surface of the connecting portion 100a. In other words, the belt-like member 4 may cover the first opening 13a. 4A to 4C are perspective views showing first to third examples of the belt-like member 4 covering the first opening 13a, respectively.

  For example, as shown in FIG. 4A, all the first openings 13 a may be covered with the band-shaped member 4. If it carries out like this, the leak of the air in all the 1st opening parts 13a of the connection part 100a can be suppressed or prevented by the strip | belt-shaped member 4 provided for every 1st opening part 13a.

  Alternatively, as shown in FIG. 4B, a part of the first openings 13 a may be covered with the belt-shaped member 4. By so doing, only a part of the plurality of first openings 13a is covered with the band-shaped member 4, so that the band-shaped member 4 can be saved.

  In addition, although the strip | belt-shaped member 4 is provided for every 1st opening part 13a in FIG. 4A and FIG. 4B, you may be provided with one connection like FIG. 4C. That is, the belt-like member 4 may be wound over the entire circumference in the circumferential direction on the radially outer surface of the connecting portion 100a. If it carries out like this, the operation | work which provides the strip | belt-shaped member 4 will become easy.

  Next, the first axial fan 1 has the first lead wire 14 as described above. The first lead wire 14 extends from the first motor unit 12. In the present embodiment, the first lead wire 14 is accommodated in the first recess 131a. More specifically, the first lead wire 14 is inserted into the first recess 131a and pulled out of the first housing 13 through the first recess 131a.

<1-3. Second axial fan>
Next, each component of the second axial fan 2 will be described with reference to FIGS. 1 and 3.

  The second axial fan 2 has the second impeller 21 as described above. The second impeller 21 has second blades 211. The 2nd blade | wing 211 is rotatable centering on the central axis CA extended in an up-down direction. When the second motor unit 22 drives the second impeller 21, the second blade 211 rotates about the central axis CA. Thus, the second axial fan 2 sucks the airflow sent from the first axial fan 1 at the upper end in the axial direction of the second axial fan 2 via the rectifying plate 3. The second axial fan 2 accelerates the flow velocity of the airflow flowing downward in the axial direction, and sends the airflow from the lower end in the axial direction of the second axial fan 2 to the lower side in the axial direction of the serial axial fan 100. .

  The second axial fan 2 has the second motor unit 22 as described above. The second motor unit 22 drives the second impeller 21 to rotate the second blade 211.

  The second axial fan 2 includes the second housing 23 as described above. The 2nd housing 23 has the 2nd cylinder part 231 as mentioned above. The 2nd cylinder part 231 is a cylinder shape extended in an axial direction, and accommodates the 2nd impeller 21 and the 2nd motor part 22 inside. The upper end portion in the axial direction of the second cylindrical portion 231 is in contact with the lower end surface in the axial direction of the rectifying plate 3 in the present embodiment. By so doing, the airflow can be prevented from flowing in the radial direction at the axial upper end of the second cylindrical portion 231. Accordingly, it is possible to prevent the occurrence of turbulent flow at the upper end in the axial direction of the second cylindrical portion 231. However, the present invention is not limited to this example, and there may be a gap between the second cylindrical portion 231 and the current plate 3 in the axial direction.

  The second housing 23 further includes the second flange portion 232 as described above. The second flange portion 232 spreads radially outward from the axial end on the connecting portion 100a side of the second cylindrical portion 231. In other words, the second flange portion 232 extends outward in the radial direction from the upper end portion in the axial direction of the second cylindrical portion 231. The second flange part 232 is connected to the first flange part 132. Thereby, the axial direction lower end part of the 1st housing 13 and the axial direction upper end part of the 2nd housing 23 are connected directly. By doing so, it is possible to ensure assembling performance equivalent to a configuration in which the rectifying plate 3 is not provided in the connecting portion 100a between the first housing 13 and the second housing 23.

  A second flat surface portion 232 a is provided on the upper end surface in the axial direction of the second flange portion 232. The second flat surface portion 232 a contacts the lower end surface in the axial direction of the rectifying plate 3. In the following, the generic name of the first plane part 132a and the second plane part 232a is referred to as “plane part 132a, 232a”. As described above, in the present disclosure, the first flange portion 132 and the second flange portion 232 are provided with the flat portions 132a and 232a that come into contact with the axial end surface of the current plate 3. Thereby, the baffle plate 3 provided between the 1st cylinder part 131 and the 2nd cylinder part 231 can be pinched | interposed by the 1st plane part 132a and the 2nd plane part 232a. Therefore, the current plate 3 can be held more reliably in the axial direction. However, the present invention is not limited to this example, and there may be a gap between at least one of the first flange portion 132 and the second flange portion 232 and the current plate 3 in the axial direction. By providing such a gap, it is possible to suppress vibration of the rectifying plate 3 and generation of noise associated therewith.

  The second housing 23 further includes the second rib 233 as described above. A radially inner end portion of the second rib 233 supports the second motor portion 22. A radially outer end portion of the second rib 233 is connected to the second cylindrical portion 231.

  As described above, the second axial fan 2 has the second lead wire 24. The second lead wire 24 extends from the second motor unit 22.

<1-4. Modified Examples of First Axial Flow Fan and Second Axial Flow Fan>
<1-4-1. Modification of first recess>
In the above-described embodiment, as shown in FIG. 3, the first cylindrical portion 131 is provided with the first recess 131 a for pulling out the first lead wire 14 to the outside of the first housing 13. Similarly, as shown in FIG. 5, a second recess 231 a for pulling out the second lead wire 24 to the outside of the second housing 23 may be provided in the second cylindrical portion 231. FIG. 5 shows an example of the second recess 231 a provided in the second cylinder portion 231. 5 corresponds to a portion C surrounded by a broken line in FIG. In FIG. 5, the 2nd recessed part 231a dented on the opposite side to the connection part 100a of an axial direction is provided in the axial direction upper end surface of the 2nd cylinder part 231. As shown in FIG. The second recessed portion 231a is recessed downward in the axial direction on the upper end surface in the axial direction of the second cylindrical portion 231 and penetrates the second cylindrical portion 231 in the radial direction. The serial axial fan 100 may be provided with both the first recess 131a and the second recess 231a, or may be provided with a second recess 231a instead of the first recess 131a. Hereinafter, the first recess 131a and the second recess 231a are collectively referred to as “recesses 131a and 231a”. Thus, in the present disclosure, the axial end surface of at least one of the cylindrical portions 131 and 231 out of the axial lower end surface of the first cylindrical portion 131 and the axial upper end surface of the second cylindrical portion 231 has an axial direction. Concave portions 131a and 231a that are recessed on the side opposite to the connecting portion 100a are provided.

  Further, in FIG. 3, the first lead wire 14 is drawn out of the first housing 13 through the first recess 131a, and in FIG. 5, the second lead wire 24 is drawn out of the second housing 23 through the second recess 231a. However, the present invention is not limited thereto, and both the first lead wire 14 and the second lead wire 24 may be drawn out of the housings 13 and 23 through the first recess 131a or the second recess 231a. That is, in the present disclosure, at least one of the first lead wire 14 and the second lead wire 24 is accommodated in the recesses 131a and 231a.

  In the present disclosure, at least a part of the recesses 131a and 231a provided on at least one of the lower axial end surface of the first cylindrical portion 131 and the upper axial end surface of the second cylindrical portion 231 is preferably rectified. It overlaps with a part of the plate 3 in the axial direction. Thus, even if at least one of the lead wires 14 and 24 accommodated in the recesses 131a and 231a is bent, the movement of the lead wires 14 and 24 toward the connecting portion 100a in the axial direction can be suppressed by the rectifying plate 3. . Furthermore, the airflow turbulence caused by the recesses 131a and 231a can be suppressed by the current plate 3. Therefore, the pressure-air volume characteristic of the serial axial fan 100 can be improved, and the blowing efficiency of the serial axial fan 100 can be further improved. Further, noise generated by the serial axial fan 100 can be reduced.

  In the present disclosure, when viewed from the axial direction, the radially outer end of the rectifying plate 3 is preferably the same as the radially outer end of the recesses 131a and 231a or has a diameter larger than the radially outer end of the recesses 131a and 231a. Inside the direction. In this way, when viewed from the axial direction, the radially outer end of the rectifying plate 3 is not on the radially outer side than the radially outer ends of the recesses 131a and 231a. Therefore, for example, as shown in FIG. 3, even when the second lead 24 extends in the axial direction along the radially outer surface of the second cylindrical portion 231 to the radially outer end of the first recess 131 a, The radially outer end does not become an obstacle. Therefore, the arrangement of the second lead wires 24 can be designed more freely. At this time, since the radially outer end portion of the rectifying plate 3 is not pushed radially inward by the second lead wire 24, deformation of the radially outer end portion of the rectifying plate 3 can be prevented.

<1-4-2. Modification of first leg>
In the embodiment described above, for example, as shown in FIG. 3, the first leg portion 132 b is provided on the first flange portion 132. Similarly, as shown in FIG. 6, the second flange portion 232 may be provided with a second leg portion 232 b protruding upward in the axial direction. FIG. 6 is a cross-sectional view showing an example of the second leg portion 232b provided in the second cylinder portion 231. As shown in FIG. 6 corresponds to a portion D surrounded by a broken line in FIG. The serial axial fan 100 may be provided with a second leg 232b instead of the first leg 132b. Or both the 1st leg part 132b and the 2nd leg part 232b may be provided like FIG. Further, the upper end portion in the axial direction of the second leg portion 232b may abut on the first flange portion 132 or may abut on the first leg portion 132b as shown in FIG. Hereinafter, the first leg 132b and the second leg 232b are collectively referred to as “legs 132b and 232b”.

  As described above, in the present disclosure, the leg portion 132b protruding in the axial direction is formed on the axial end surface on the connecting portion 100a side of at least one of the first flange portion 132 and the second flange portion 232. 232b is provided. The leg portions 132b and 232b provided on one flange portion 132 and 232 abut on the other flange portions 132 and 232 or the leg portions 132b and 232b provided on the other flange portions 132 and 232, respectively. In this way, in the axial direction, a space having the same axial length as the legs 132b and 232b can be provided between the first cylindrical portion 131 and the second cylindrical portion 231. Accordingly, by connecting the first flange portion 132 and the second flange portion 232, the first housing 13 and the second housing 23 can be directly connected, and between the first tube portion 131 and the second tube portion 231. The current plate 3 can be accommodated in a space in the axial direction.

  Moreover, the 2nd leg part 232b is provided in the radial direction outer side rather than the 2nd recessed part 231a in FIG. Thus, in the present disclosure, the leg portions 132b and 232b are provided on the outer side in the radial direction than the concave portions 131a and 231a when viewed from the axial direction. If it carries out like this, leg part 132b, 232b will not overlap with recessed part 131a, 231a in an axial direction. Therefore, the lead wires 14 and 24 can be easily accommodated in the recesses 131a and 231a, and the current plate 3 and the recesses 131a and 231a can be easily stacked in the axial direction. Further, the airflow can be smoothly flowed in the axial direction without being affected by the legs 132b and 232b in the portions overlapping the recesses 131a and 231a of the rectifying plate 3. Further, when the housings 13 and 23 having the leg portions 132b and 232b on the flange portions 132 and 232 are molded by a mold, the mold can be opened in the vertical direction. Therefore, the mold structure can be simplified, and the molding process of the housings 13 and 23 using the mold can be easily performed.

  Moreover, the axial direction length df2 shown in FIG. 6 of the 2nd leg part 232b is below the axial direction length dc shown in FIG. The axial length df2 of the second leg 232b is the axial width between the second flat surface 232a and the upper end of the second leg 232b in the axial direction. Hereinafter, a general term of the axial length df1 of the first leg 132b and the axial length df2 of the second leg 232b is referred to as an “axial length df”. Thus, in the present disclosure, the axial length df of the leg portions 132b and 232b is equal to or less than the axial length dc of the rectifying plate 3. The axial length df of the leg portions 132b and 232b is determined by the axial end portions of the flange portions 132 and 232 provided with the leg portions 132b and 232b on the flat surface portions 132a and 232a and the connecting portions 100a side of the leg portions 132b and 232b. Is the axial width between. In this way, in the axial direction, the current plate 3 can be held between the lower end portion in the axial direction of the first cylindrical portion 131 and the upper end portion in the axial direction of the second cylindrical portion 231.

  Moreover, the 2nd leg part 232b is plural, and each is provided in the circumferential direction. That is, there are a plurality of leg portions 132b and 232b, which are respectively provided in the circumferential direction.

<1-5. Current plate>
Next, the configuration of the rectifying plate 3 will be described with reference to FIG. FIG. 7 is a perspective view showing an example of the current plate 3.

  The serial axial fan 100 includes the rectifying plate 3 as described above. The rectifying plate 3 includes a plurality of hollow cells 3 a and a lattice-shaped partition wall 31. Each of the hollow cells 3a of the rectifying plate 3 is partitioned by a partition wall 31 and penetrates in the axial direction. Further, the plurality of hollow cells 3a are uniformly two-dimensionally arranged from the central portion of the rectifying plate 3 to the outer edge portion. According to such a structure, a frame or the like is not provided on the outer edge portion of the current plate 3. Therefore, the airflow rectifying effect by the hollow cell 3a can be obtained up to the outer edge. Further, the current plate 3 can be created without using a mold or the like. In other words, the plurality of hollow cells 3 a have a structure that is partitioned by the lattice-shaped partition walls 31 and penetrate the rectifying plate 3 in the axial direction. Therefore, the rectifying plate 3 can ensure the maximum air flow path in the axial direction.

  In this embodiment, the rectifying plate 3 has a honeycomb structure in which hexagonal hollow cells 3a are two-dimensionally arranged when viewed from the axial direction. In this way, by adopting a honeycomb structure for the rectifying plate 3, the effect of rectifying the airflow sent from the first axial fan 1 can be improved and the air resistance during rectification can be reduced. Therefore, the pressure-air volume characteristic of the serial axial fan 100 can be enhanced. However, it is not limited to this illustration, The shape seen from the axial direction of the hollow cell 3a may be a polygonal shape other than a hexagonal shape, a circular shape, or the like.

  The opening ratio of the hollow cells 3a of the rectifying plate 3 having a honeycomb structure is 90% or more. Here, the opening ratio is a ratio of the sum of the opening areas of all the hollow cells 3 a whose entire circumference is partitioned by the partition walls 31 to the total area of the axial end surfaces of the rectifying plate 3. In the current plate formed by resin molding or the like, it is difficult to make the aperture ratio 90% or more. In the rectifying plate 3 having a honeycomb structure, by setting the aperture ratio to 90% or more, a higher rectifying effect and a lower air resistance can be realized than the rectifying plate having other structure formed by resin molding. .

  The width Wc between two sides of the hexagonal hollow cell 3a facing and parallel to each other is larger than the radial width of the axial end portion of the first cylindrical portion 131 and the second cylindrical portion 231 on the connecting portion 100a side. . That is, the width Wc is larger than the radial width dt1 shown in FIG. 2 at the lower end portion in the axial direction of the first cylindrical portion 131 and the radial width at the upper end portion in the axial direction of the second cylindrical portion 231. In this way, when viewed from the axial direction, in the hollow cell 3a that overlaps the axial end on the connecting portion 100a side of the first cylindrical portion 131 and the second cylindrical portion 231, the axial end covers all the hollow cells 3a. I can not. Therefore, when viewed from the axial direction, the hollow cell 3a that overlaps the axial direction end portion on the connecting portion 100a side of the first cylindrical portion 131 and the second cylindrical portion 231 covers the vicinity of the inner wall of the first cylindrical portion 131 and the second cylindrical portion 231. The flowing airflow can be rectified. Therefore, generation | occurrence | production of the turbulent flow near the inner wall in this axial direction edge part of the 1st cylinder part 131 and the 2nd cylinder part 231 can be suppressed or prevented.

<2. Modification of Embodiment>
Next, a modification of the embodiment will be described. Hereinafter, a configuration different from the above-described embodiment will be described. Moreover, the same code | symbol is attached | subjected to the component similar to the above-mentioned embodiment, and the description may be abbreviate | omitted.

<2-1. First Modification>
In the above-described embodiment, the second rib 233 is provided at the lower portion in the axial direction of the second axial fan 2 (see FIG. 3). However, the second rib 233 may be provided at the upper part in the axial direction of the second axial fan 2 without being limited to this example.

  FIG. 8 is a cross-sectional view illustrating a first modification of the serial axial fan 101 according to the first modification. FIG. 8 shows a cross-sectional structure when the serial axial fan 101 is cut along a virtual plane including the central axis CA. In FIG. 8, the arrangement of the respective components of the first axial fan 1 and the rectifying plate 3 is the same as in FIG. However, the arrangement of the components of the second axial fan 2 is opposite to that in FIG.

  In the first modification, the second rib 233 has a gap with the lower end surface in the axial direction of the rectifying plate 3 and faces the axial direction. The minimum axial width of the gap (Wri2 in FIG. 8) is preferably smaller than the width (for example, the width Wc shown in FIG. 7) in the direction perpendicular to the axial direction of the hollow cell 3a of the rectifying plate 3. In this way, by providing a gap narrower than the width in the direction perpendicular to the axial direction of the hollow cell 3a between the second rib 233 and the rectifying plate 3, while maintaining the rectifying effect by the second rib 233, the first It is possible to prevent a decrease in the amount of airflow passing through the hollow cells 3a that overlap the two ribs 233 in the axial direction.

  As described above, according to the above-described embodiment and the first modification, at least one of the first rib 133 and the second rib 233 is opposed to the axial direction through the current plate 3. The minimum axial width of the gap between the second rib 233 and the rectifying plate 3 is preferably smaller than the width Wc between the two sides of the hexagonal hollow cell 3a of the rectifying plate 3 having a honeycomb structure. In this way, the gap between at least one of the ribs 133 and 233 and the rectifying plate 3 is provided to be narrower than the width Wc in the direction perpendicular to the axial direction of the hollow cell 3a. While maintaining the rectifying effect, it is possible to prevent a decrease in the amount of airflow passing through the hollow cell 3a that overlaps at least one of the ribs 133 and 233 in the axial direction. The reason is that when there is no gap between at least one rib 133, 233 and the rectifying plate 3 in the axial direction, the size of the opening on the inlet side and the outlet side of the hollow cell 3a is different. This causes the effect of the current plate 3 to be reduced. Furthermore, when the axial width of the gap between at least one of the ribs 133 and 233 and the rectifying plate 3 is too wide, the effect of rectifying the airflow flowing in the axial direction by the at least one of the ribs 133 and 233 is reduced. .

  The axial width Wri2 of the gap on the radially inner side between the second rib 233 and the axial lower end surface of the rectifying plate 3 is preferably the radially outer side between the second rib 233 and the axial lower end surface of the rectifying plate 3. Is smaller than the axial width Wro2 of the gap. Hereinafter, the axial width Wri1 of the gap between the first rib 133 and the rectifying plate 3 in the radial direction and the axial width Wri2 of the gap between the second rib 233 and the rectifying plate 3 in the radial direction will be collectively referred to. Is referred to as “axial width Wri”. The axial width Wro1 of the gap on the radially outer side between the first rib 133 and the rectifying plate 3 and the axial width Wro2 of the gap on the radially outer side of the second rib 233 and the rectifying plate 3 are collectively referred to as “axis”. This is referred to as “direction width Wro”.

  Furthermore, in this embodiment, as shown in FIG. 7, the axial width Wri2 is smaller than the width Wc between the two sides of the hexagonal hollow cell 3a in the rectifying plate 3. On the other hand, the axial width Wro is larger than the width Wc between two sides of the hexagonal hollow cell 3a. Thus, in the present disclosure, the axial width Wri of the gap between the radial inner ends of the ribs 133 and 233 and the rectifying plate 3 is smaller than the width Wc between the two sides of the hexagonal hollow cell. On the other hand, the axial width Wro of the gap between the radially outer ends of the ribs 133 and 233 and the rectifying plate 3 is larger than the width Wc between the two sides of the hexagonal hollow cell 3a. The optimum value of the axial width of the gap for improving the air pressure and air flow and suppressing the occurrence of turbulent flow differs between the radially inner end and the radially outer end of the ribs 133 and 233. . The radially outer ends of the ribs 133 and 233 are easily affected by the radially inner side surfaces of the cylindrical portions 131 and 231. Therefore, by making the axial width Wro of the gap larger than the width Wc between the two sides of the hollow cell 3a, the pressure-air flow characteristics of the series axial fan 101 can be improved.

  In addition, the width of the portion of the second rib 233 facing the rectifying plate 3 in the axial direction is preferably equal to or less than the width Wc between the two sides of the hexagonal hollow cell 3a. In addition, this part is the axial direction upper end part of the 2nd rib 233, for example. For example, the width is the minimum width in a direction perpendicular to the axial direction of the second rib 233. That is, in the first modification, the width of the portion of the at least one rib 133, 233 facing the rectifying plate 3 in the axial direction is equal to or smaller than the width (Wc) between the two sides of the hexagonal hollow cell 3a. In this way, the hexagonal hollow cell 3a is not blocked by at least one of the ribs 133 and 233, and therefore the pressure of the airflow flowing through the rectifying plate 3 from the first axial fan 1 to the second axial fan 2 and The air volume can be improved and the occurrence of turbulent flow can be suppressed.

  In the first modified example, the lower end portion in the axial direction of the first motor unit 12 faces the upper end portion in the axial direction of the second motor unit 22 via the rectifying plate 3. Here, at least one of the lower end portion in the axial direction of the first motor unit 12 and the upper end portion in the axial direction of the second motor unit 22 may be in contact with the end surface in the axial direction of the rectifying plate 3. For example, when both the lower end in the axial direction of the first motor unit 12 and the upper end in the axial direction of the second motor unit 22 are in contact with the rectifying plate 3, the rectifying plate 3 is moved by the first motor unit 12 and the second motor unit 22. Can be sandwiched and held. Alternatively, both the lower end in the axial direction of the first motor unit 12 and the upper end in the axial direction of the second motor unit 22 may be opposed to the axial end surface of the rectifying plate 3 in the axial direction with a gap.

<2-2. Second Modification>
In the embodiment and the first modification described above, the first opening 13 a is provided in the first housing 13. Similarly, the second opening 23 a may be provided in the second housing 23. FIG. 9 is a perspective view of the serial axial fan 102 according to the second modification.

  The second opening 23a is provided at the upper end in the axial direction of the second housing 23 and is recessed downward in the axial direction. The second opening 23a is provided at the same circumferential position as the first opening 13a. Hereinafter, the first opening 13a and the second opening 23a are collectively referred to as “openings 13a and 23a”.

  The second opening 23 a penetrates the second housing 23 in the radial direction, and particularly penetrates a part of the second cylinder part 231 and a part of the second flange part 232 in the radial direction. In the second opening 23 a, the radially outer end surface of the rectifying plate 3 is exposed to the outside of the serial axial fan 102. Moreover, the radial direction outer end part of the baffle plate 3 exists in the radial inside rather than the 2nd opening part 23a, or the same position as the 2nd opening part 23a.

  The serial axial fan 102 may be provided with a second opening 23a together with the first opening 13a, or may be provided with a second opening 23a instead of the first opening 13a. When the second opening 23a is provided together with the first opening 13a, the second opening 23a is preferably provided at the same circumferential position as the first opening 13a. As described above, in the present disclosure, in the connecting portion 100a, at least one of the first housing 13 and the second housing 23 has an opening penetrating the at least one housing 13, 23 in the radial direction. Portions 13a and 23a are provided.

  Here, in FIG. 4A to FIG. 4C, the first opening 13 a is covered with the belt-like member 4. Similarly to this, the second opening 23 a may be covered with the belt-like member 4. Thus, in the present disclosure, the belt-like member 4 covers the openings 13a and 23a. If it carries out like this, the leak of the air in the opening parts 13a and 23a of the connection part 100a can be suppressed or prevented by the strip | belt-shaped member 4. FIG. Therefore, it is possible to improve the pressure-air volume characteristic of the serial axial fan 102. Furthermore, the generation of noise due to air leakage can be suppressed or prevented.

  More specifically, when there are a plurality of openings 13a and 23a, the belt-like member 4 may cover all the openings 13a and 23a as in FIG. 4A. If it carries out like this, the leak of the air in all the opening parts 13a and 23a of the connection part 100a can be suppressed or prevented by the strip | belt-shaped member 4. FIG.

  Alternatively, when there are a plurality of openings 13a and 23a, the belt-like member 4 may cover some of the openings 13a and 23a as in FIG. 4B. In this way, since only some of the openings 13a and 23a are covered with the strip member 4, the strip member 4 can be saved. For example, when installing each of the openings 13a and 23a adjacent to each other when installing a plurality of series axial fans 102, air leakage is suppressed even if the openings 13a and 23a are not covered with the belt-like member 4. This is particularly effective because it can be prevented.

  Or similarly to FIG. 4C, the strip | belt-shaped member 4 may be wound over the perimeter of the circumferential direction in the radial direction outer surface of the connection part 100a. And the strip | belt-shaped member 4 may cover all the opening parts 13a and 23a. If it carries out like this, the operation | work which provides the strip | belt-shaped member 4 will become easy. Moreover, since the strip | belt-shaped member 4 covers all the opening parts 13a and 23a, the leak of the air in the opening parts 13a and 23a can be prevented more reliably. Moreover, since the number of steps of the tape application work is reduced, the tape application work becomes easy.

<2-3. Third Modification>
In the embodiment, the first modification, and the second modification, the openings 13a and 23a are provided in the housings 13 and 23, respectively. However, the present invention is not limited to these examples, and the openings 13 a and 23 a may not be provided in the housings 13 and 23.

  FIG. 10 is a perspective view of the serial axial fan 103 according to the third modification. FIG. 11 is a cross-sectional view of the serial axial fan 103 taken along the dashed-dotted line EE in FIG. FIG. 10 shows a cross-sectional structure when the serial axial fan 103 is cut along a virtual plane including the central axis CA. FIG. 11 shows a cross-sectional structure of the serial axial fan 103 cut along a virtual plane perpendicular to the axial direction.

  In the third modification, the openings 13 a and 23 a are not provided in the housings 13 and 23. On the other hand, as shown in FIGS. 10 and 11, the first housing 13 further includes a first wall portion 134. The first wall portion 134 is provided between the first leg portions 132b adjacent in the circumferential direction. That is, one end portion in the circumferential direction of the first wall portion 134 is connected to one of the first leg portions 132b adjacent in the circumferential direction. The other end portion in the circumferential direction of the first wall portion 134 is connected to the other one of the first leg portions 132b adjacent in the circumferential direction.

  Further, the first wall portion 134 is provided at the lower end portion in the axial direction of the first housing 13 and protrudes downward in the axial direction from the radially outer end portion of the lower end surface in the axial direction of the first housing 13. The first wall portion 134 is in contact with the axial upper end surface of the second housing 23. More specifically, in the third modification, the first wall portion 134 is provided on the lower end surface in the axial direction of the first tube portion 131 and the lower end surface in the axial direction of the first flange portion 132. That is, a part of the first wall portion 134 protrudes downward in the axial direction from the radially outer end portion of the lower end surface in the axial direction of the first cylindrical portion 131 and comes into contact with the upper end portion in the axial direction of the second cylindrical portion. Further, the remaining part of the first wall portion 134 protrudes downward in the axial direction from the radially outer end portion of the lower end surface in the axial direction of the first flange portion 132 and contacts the upper end portion in the axial direction of the second flange portion 232. Touch. Thereby, without exposing the radial direction outer side surface of the baffle plate 3 to the exterior of the 1st housing 13, it is between the 1st cylinder part 131 and the 2nd cylinder part 231 in an axial direction, and from the 1st wall part 134. The rectifying plate 3 can be accommodated in the radially inner space. Further, for example, as shown in FIG. 11, when the radially outer end of the rectifying plate 3 is in contact with the radially inner side surface of at least a part of the first wall portion 134, the rectifying plate 3 in the direction perpendicular to the axial direction Positioning is possible.

  10 and 11, the second housing 23 may have a second wall portion 234 as shown in FIG. 12. FIG. 12 is a cross-sectional view illustrating an example of the second wall portion 234. 12 corresponds to, for example, a cross-sectional structure taken along one-dot chain line FF in FIG.

  The second wall portion 234 is provided at the upper end portion in the axial direction of the second housing 23. The second wall portion 234 protrudes axially upward from the radially outer end portion of the axial upper end surface of the second housing 23 and abuts on the axial lower end surface of the first housing 13. For example, the second wall portion 234 contacts the lower end surface in the axial direction of the first tube portion 131 and the lower end surface in the axial direction of the first flange portion 132. Or the 2nd wall part 234 contact | abuts the axial direction lower end part of the 1st wall part 134 provided in the 1st housing 13 like FIG. In the following, the generic name of the first wall portion 134 and the second wall portion 234 will be referred to as “wall portions 134, 234”.

  As described above, in the present disclosure, at least one of the first housing 13 and the second housing 23 has an axial end on the connection portion 100a side of at least one of the housings 13, 23. Wall portions 134 and 234 projecting in the axial direction from the radially outer end portion are provided. The wall parts 134 and 234 are provided between the leg parts 132b and 232b adjacent in the circumferential direction. In this way, one of the walls 134 and 234 provided at one axial end of the housings 13 and 23 is a wall provided at the other axial end of the housings 13 and 23 or the other axial ends of the housings 13 and 23. It abuts against the other of the parts 134 and 234. Thereby, without exposing the radial direction outer side surface of the baffle plate 3 to the exterior of the housings 13 and 23, between the 1st cylinder part 131 and the 2nd cylinder part 231, and wall part 134,234 in an axial direction. The rectifying plate 3 can be accommodated in the radially inner space. Therefore, the leakage of the airflow in the connection part 100a can be further suppressed. Therefore, the pressure-air volume characteristic of the serial axial fan 103 can be improved. Furthermore, the generation of noise due to air leakage can be suppressed or prevented. Further, for example, as shown in FIG. 11, the radially outer end portion of the rectifying plate 3 abuts against the radially inner side surfaces of at least some of the wall portions 134 and 234, so that the rectifying plate 3 in the direction perpendicular to the axial direction is Positioning is possible. Therefore, the assembly work of the serial axial fan 103 is facilitated, and the assembly tolerance of the serial axial fan 103 can be reduced.

<3. Other>
In the foregoing, an exemplary embodiment has been described in the present disclosure. Note that the scope of the present invention is not limited to the present disclosure. The present disclosure can be implemented with various modifications without departing from the gist of the present invention. In addition, the items described in the present disclosure can be arbitrarily combined as long as no contradiction occurs.

  The present disclosure is useful for an apparatus in which two axial fans 1 and 2 are connected in series.

  DESCRIPTION OF SYMBOLS 100, 101, 102, 103 ... Series type axial fan, 100a ... Connection part, 1 ... 1st axial fan, 11 ... 1st impeller, 111 ... 1st blade | wing, 12 ... 1st motor part, 13 ... 1st housing, 13a ... 1st opening part, 131 ... 1st cylinder part, 131a ... 1st recessed part, 132 ... 1st flange part , 132a... First plane portion, 132a... First leg portion, 133... First rib, 134... First wall portion, 14. Two-axis fan, 21 ... second impeller, 211 ... second blade, 22 ... second motor part, 23 ... second housing, 23a ... second opening, 231 ... Second cylindrical portion, 231a, second concave portion, 232, second flange portion, 232a, second flat portion, 233, 2nd rib, 234 ... 2nd wall part, 24 ... 2nd lead wire, 3 ... Current plate, 3a ... Hollow cell, 31 ... Partition, 4 ... Strip member, CA ... Center axis

Claims (15)

A first axial fan;
A second axial fan connected in series with the first axial fan;
A rectifying plate in which a plurality of hollow cells that are partitioned by a lattice-shaped partition wall and penetrate in the axial direction are two-dimensionally arranged evenly to the outer edge,
With
The first axial fan is
A first impeller having a first blade rotatable about a central axis extending in the vertical direction;
A first motor unit that drives the first impeller to rotate the first blade;
A first housing that is axially extending in the axial direction and has a first cylindrical portion that houses the first impeller and the first motor portion;
A first lead wire extending from the first motor section;
Have
The second axial fan is
A second impeller having a second blade rotatable about the central axis;
A second motor unit that drives the second impeller to rotate the second blade;
A second housing having a cylindrical shape extending in the axial direction and having a second cylindrical portion that houses the second impeller and the second motor portion;
A second lead wire extending from the second motor portion;
Have
An axial lower end portion of the first housing and an axial upper end portion of the second housing are directly connected,
The rectifying plate is provided at a connecting portion between the first housing and the second housing,
The lower end portion in the axial direction of the first cylindrical portion is opposed to the upper end portion in the axial direction of the second cylindrical portion in the axial direction via the current plate,
On the axial end surface of at least one of the axial lower end surface of the first cylindrical portion and the axial upper end surface of the second cylindrical portion, there is a recess that is recessed on the opposite side to the connecting portion in the axial direction. Provided,
At least one of the first lead wire and the second lead wire is received in the recess,
A serial axial fan in which at least a part of the recess overlaps with a part of the current plate in the axial direction.   2. The series type according to claim 1, wherein when viewed from the axial direction, the radially outer end of the current plate is the same as the radially outer end of the recess or radially inward of the radially outer end of the recess. Axial fan. The first housing has a first flange portion that extends radially outward from an axial end portion on the connecting portion side of the first cylindrical portion,
The second housing has a second flange portion that extends radially outward from an axial end portion on the connecting portion side of the second cylindrical portion,
The leg part which protrudes in an axial direction is provided in the axial direction end surface in the said connection part side of the at least one flange part of the said 1st flange part and the said 2nd flange part. The described series axial fan.   4. The serial axial fan according to claim 3, wherein when viewed from the axial direction, the leg portion is provided radially outside the concave portion. 5.   5. The serial axial fan according to claim 3, wherein an axial length of the leg portion is equal to or less than an axial length of the rectifying plate. There are a plurality of flange portions provided with the leg portions, each provided in the circumferential direction,
A wall portion protruding in the axial direction from a radially outer end portion of the at least one housing is provided at an axial end portion on the connecting portion side of at least one of the first housing and the second housing. And
The serial axial fan according to any one of claims 3 to 5, wherein the wall portion is provided between the leg portions adjacent to each other in the circumferential direction.   The serial axial fan according to any one of claims 3 to 6, wherein the first flange portion and the second flange portion are provided with a flat portion that comes into contact with an axial end surface of the rectifying plate. . The rectifying plate has a honeycomb structure in which the hexagonal hollow cells are two-dimensionally arranged when viewed from the axial direction,
The width between two sides of the hexagonal hollow cell facing and extending in parallel with each other is larger than the radial width of the axial end portion on the connecting portion side of the first tube portion and the second tube portion, The in-line axial fan according to any one of claims 1 to 7.   The series axial fan according to claim 8, wherein an opening ratio of the hollow cells of the rectifying plate having the honeycomb structure is 90% or more. The first housing further includes a first rib that supports the first motor portion at a radially inner end portion and has a radially outer end portion connected to the first cylindrical portion;
The second housing further includes a second rib that supports the second motor portion at a radially inner end portion and has a radially outer end portion connected to the second tubular portion;
At least one of the first rib and the second rib is opposed to the current plate in the axial direction with a gap,
The series axial flow according to claim 8 or 9, wherein a minimum axial width of the gap is narrower than a width between the two sides of the hexagonal hollow cell of the rectifying plate having the honeycomb structure. fan.   11. The serial axial fan according to claim 10, wherein a width of a portion of the at least one rib facing the current plate in the axial direction is equal to or smaller than a width between the two sides of the hexagonal hollow cell. The axial width of the gap between the radial inner end of the at least one rib and the rectifying plate is smaller than the width between the two sides of the hexagonal hollow cell,
The axial width of the gap between the radial outer end of the at least one rib and the rectifying plate is larger than the width between the two sides of the hexagonal hollow cell. A series axial fan described in 1. A belt-like member provided on the radially outer side surface of the connecting portion;
In the connecting portion, at least one of the first housing and the second housing is provided with an opening that penetrates the at least one housing in a radial direction,
The serial axial fan according to any one of claims 1 to 12, wherein the belt-shaped member covers the opening. The openings are plural,
The series-type axial fan according to claim 13, wherein the belt-shaped member covers a part of the opening.   The series-type axial fan according to claim 13, wherein the belt-like member is wound around the entire circumference in the radial direction outer surface of the connecting portion and covers all the openings.

Images