JP4116359B2 - Centrifugal blower - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a centrifugal blower used for a vehicle air conditioner or the like.
[0002]
[Prior art]
FIG. 3 is a schematic longitudinal sectional view showing an example of a centrifugal blower used for a vehicle air conditioner and the like, and FIG. 4 is a sectional view taken along line BB in FIG. The centrifugal fan includes a centrifugal fan 1, a drive motor 2 that rotationally drives the centrifugal fan 1, and a scroll casing 3 that houses the centrifugal fan 1.
[0003]
The centrifugal fan 1 includes a rotary shaft 4 that extends vertically, a bottom wall 5 that is circular in plan view, the center of which is fixed to the rotary shaft 4, and a lower end portion that is erected around the rotary shaft 4 at a predetermined angular interval. .. Are fixed to the peripheral edge of the bottom wall 5, and a holding ring 7 that fixes the upper ends of these blades 6, 6.
[0004]
The drive motor 2 includes a rotating unit 8 and a fixed unit 9. The rotating unit 8 is fixed to the rotating shaft 4 of the centrifugal fan 1, and the fixed unit 9 is fixed to the scroll casing 3. The bottom wall 5 of the centrifugal fan 1 is formed in a mountain shape in cross section so that the rotating portion 8 of the drive motor 2 can be received from below. Further, the bottom wall 5 is formed with a plurality of through holes 5a, 5a.
[0005]
The scroll casing 3 is formed of synthetic resin or the like, has a bell mouth 10 that forms an air intake port on the upper surface, and has an opening 11 that receives the fixing portion 9 of the drive motor 2 on the bottom surface. Around the opening 11, there is formed an air flow path 12 for discharging the air blown by the centrifugal fan 1 in a spiral around the centrifugal fan 1 as indicated by arrows in FIG. Reference numeral 13 denotes a discharge port.
[0006]
When the drive motor 2 is driven, the centrifugal fan 1 rotates about the rotation shaft 4, and air is sucked in the direction of the rotation shaft 4 from above the scroll casing 3. This air passes between the blades 6, 6... Is blown outward in the radial direction, and circulates in the air flow path 12 in a spiral shape and is discharged from the discharge port 13.
[0007]
At this time, if the air flowing in the air flow path 12 flows into the drive motor 2 side, abnormal noise is generated. Therefore, an annular rib 14 projecting upward is formed in a portion around the drive motor 2 inside the scroll casing 3. The air in the air flow path 12 is prevented from flowing into the drive motor 2 side.
[0008]
If the ribs 14 are in an endless state, the water sucked together with the air by the centrifugal fan 1 may stay inside the ribs 14 to give off a strange odor or corrode the drive motor 2. Therefore, a notch 15 is provided in the rib 14 so that water inside the rib 14 is discharged into the air flow path 2 together with the air flow generated by the centrifugal fan 1.
[0009]
[Problems to be solved by the invention]
However, when such a notch 15 is provided, there is a problem that an abnormal noise is generated when the air flow passing through the air flow path 12 hits the notch 15. In particular, when the centrifugal blower is installed so that the discharge port 13 faces downward, the notch 15 is provided in the lowest part of the rib 14, that is, in the vicinity of the discharge port 13 in order to drain the water inside the rib 14. There is a need. However, since the air blowing pressure is large in the vicinity of the discharge port 13, if the cutout portion 15 is provided in this part, abnormal noise increases. Therefore, conventionally, the notch 15 cannot be provided in the vicinity of the discharge port 13, and the centrifugal blower cannot be installed so that the discharge port 13 faces down.
[0010]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a centrifugal fan that reduces noise and improves the degree of freedom of installation posture.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, according to a first aspect of the present invention, a large number of blades are provided at predetermined intervals around a rotating shaft extending vertically, and air sucked from the direction of the rotating shaft is blown outwardly. A centrifugal fan, a drive motor that rotationally drives the centrifugal fan, and a scroll that houses the centrifugal fan and has an air flow path for discharging the air blown by the centrifugal fan in a spiral around the centrifugal fan An annular rib that is formed so as to protrude upward in a portion around the drive motor inside the scroll casing and prevents air in the air flow path from flowing into the drive motor side; A centrifugal blower provided with a notch for draining the water inside the rib into the air flow path formed in the rib, and flows in the air flow path A guide for straightening member so as not to hit the air to the notch is provided, it is characterized in that the tip of the rectifying member is provided to extend toward the nose portion.
[0012]
According to a second aspect of the present invention, in the centrifugal blower according to the first aspect, the rectifying member is formed integrally with the scroll casing.
[0014]
【The invention's effect】
According to the first aspect of the present invention, since the air flowing in the air flow path is guided so that the rectifying member does not hit the notch, no abnormal noise is generated. Accordingly, since it is possible to discharge opening is disposed such that the bottom, thereby improving the degree of freedom of installation posture.
[0015]
According to the second aspect of the present invention, the number of parts and the manufacturing cost are reduced by integrally forming the flow regulating member in the scroll casing.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic longitudinal sectional view of a centrifugal fan according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line AA in FIG. In the present embodiment, the same or similar parts as those in the conventional example are denoted by the same reference numerals, and redundant description is omitted.
[0018]
This centrifugal blower is a part of an air conditioning unit for a vehicle, and is taken in from an outside air intake (not shown) for taking in air outside the passenger compartment and an inside air inlet (not shown) for taking in air inside the passenger compartment. Air is guided to an evaporator (not shown).
[0019]
In the present embodiment, the notch 15 is provided in the vicinity of the discharge port 13 in the rib 14. The rib 14 is opposed to the upstream portion 14 a of the notch 15, substantially parallel to the air flow path 12, and is opposed to the outer surface of the downstream portion 14 b of the notch 15 in the rib 14 with a gap 16. The extension portion 14c (rectifying member) is integrally formed. Note that the tip of the extension portion 14 c is separated from the nose portion 3 a of the scroll casing 3.
[0020]
According to such a configuration, the water inside the rib 14 enters the gap 16 from the notch 15 together with the air flow generated by the centrifugal fan 1, passes between the extension portion 14 c and the nose portion 3 a, and passes through the air flow path 12. Flows in.
[0021]
And since the air which flows through the inside of the air flow path 12 is guide | induced to the direction of the discharge outlet 13 by the extension part 14c, and it strikes against the notch part 15, an abnormal noise does not arise. Therefore, there is no problem even if the notch 15 is located in the vicinity of the discharge port 13 where the blowing pressure is high.
[0022]
In this embodiment, since the extension portion 14c is formed so as to extend substantially parallel to the air flow path 12, the air resistance generated between the air flowing in the air flow path 2 and the extension portion 14c is small, The blowing resistance does not increase during blowing.
[0023]
According to the present invention, the notch portion can be provided in any part of the rib, and the centrifugal blower can be installed so that the discharge port side having a high blowing pressure is at the bottom. The degree of freedom is improved and the design becomes easy, and the performance of the air conditioner and the like can be improved.
[0024]
In addition, this invention is not limited to the said embodiment, A various deformation | transformation can be given to the said embodiment in the range which does not deviate from the summary of this invention.
[Brief description of the drawings]
FIG. 1 is a schematic longitudinal sectional view of a centrifugal blower that is an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
FIG. 3 is a schematic longitudinal sectional view of a conventional centrifugal blower.
4 is a cross-sectional view taken along line BB in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Centrifugal blower 2 Drive motor 3 Scroll casing 4 Rotating shaft 6 Wing 12 Air flow path 13 Discharge port 14 Rib 14c Extension part (rectifying member)
15 Notch

Claims (2)

A centrifugal fan in which a large number of blades are provided at predetermined intervals around a rotating shaft extending vertically, and blows air sucked from the direction of the rotating shaft in a radially outward direction, a driving motor that rotationally drives the centrifugal fan, A scroll casing that houses a centrifugal fan and has an air flow path for discharging the air blown by the centrifugal fan around the centrifugal fan in a spiral shape, and around the drive motor inside the scroll casing An annular rib that is formed so as to protrude upward in the portion and prevents the air in the air flow path from flowing into the drive motor side, and water that is formed in the rib and that is inside the rib is passed through the air flow path. In a centrifugal blower provided with a notch for draining into the air, rectification for guiding the air flowing in the air flow path so as not to hit the notch The timber is provided, a centrifugal blower, characterized in that the tip of the rectifying member is provided to extend toward the nose portion.   The centrifugal blower according to claim 1, wherein the rectifying member is formed integrally with the scroll casing.

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