JP3982375B2 - Cross-flow fan - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a once-through fan used in an air conditioner that performs indoor cooling or heating.
[0002]
[Prior art]
FIG. 5 is a front view of a cross-flow fan in the prior art, and FIG. 6 is a cross-sectional view taken along line X1-X2 of FIG. FIG. 7 is an enlarged view of part a in FIG.
[0003]
As shown in FIG. 7, the thickness gradually increases from the outer peripheral end O toward the inner peripheral direction, and reaches the maximum thickness at the A1-A2 position. The wall thickness gradually decreases from the A1-A2 position to the B1-B2 position, and rapidly expands at the level difference at the B1-B2 position. The wall thickness gradually decreases from the B1-B2 position to the inner peripheral edge I. Further, the outer peripheral end O and the inner peripheral end I have a round shape (for example, Japanese Patent Application Laid-Open No. 2003-28089 ).
[0004]
In addition, a blade whose thickness gradually increases from the outer peripheral end toward the inner peripheral direction is known (for example, see Patent Document 1).
[0005]
[Patent Document 1]
Japanese Patent Laid-Open 2001-323891 [0006]
[Problems to be solved by the invention]
However, in the above-described conventional technology, small peeling occurs due to a step at the front edge of the blade of the crossflow fan. The turbulence is increased by the occurrence of the separation, leading to deterioration of the air flow performance. Further, it leads to an increase in noise when disturbed fluid is released into the room.
[0007]
[Means for Solving the Problems]
In order to solve the above-described problems in the prior art, the present invention provides an air conditioner including a cross-flow fan for an indoor unit, and the cross-sectional shape of the blade of the cross-flow fan becomes narrower from the inner peripheral side toward the outer peripheral side. As the cross-sectional width of the inner peripheral side end portion is larger than the cross-sectional width of the main wing portion, a step substantially perpendicular to the camber line is provided, and the corner portion of the main wing portion and the step, and the step portion and the inner peripheral side are provided. The cross-flow fan is characterized in that an inclined portion is provided in at least one of the corner portions with the end portion. That is, the blade shape of the cross-flow fan is characterized in that in the thickness distribution of each blade, a step is provided in the middle and an inclined portion is provided so as to sandwich the step.
[0008]
With this shape, the stepped portion becomes smaller, the turbulence component generated from the portion becomes smaller, and the deterioration of the air flow performance is suppressed and the increase in noise is suppressed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
In the cross-flow fan according to the first embodiment of the present invention, the cross-sectional shape of the blade of the cross-flow fan becomes narrower from the inner peripheral side toward the outer peripheral side, and the cross-sectional width of the inner peripheral side end portion is larger than the cross-sectional width of the main wing portion. As shown in the figure, a step substantially perpendicular to the camber line is provided, and an inclined portion is provided at at least one of the corner between the main wing and the step and the corner between the step and the inner peripheral end. It is a once-through fan characterized by that. That is, in the thickness distribution of each blade, the blade shape of the cross-flow fan is characterized in that a step is provided in the middle and an inclined portion is provided so as to sandwich the step .
[0010]
Na us, stepped difference portion of the present invention, For the inclined portion may be provided on both sides of each blade.
[0011]
(Embodiment 1)
FIG. 1 is a front view of a cross-flow fan according to a first embodiment of the present invention, and FIG. 2 is a sectional view taken along line X1-X2 of FIG. FIG. 3 is an enlarged view of part a in FIG. A one-dot chain line indicates a camber line.
[0012]
As shown in FIG. 3, the wall thickness of the main wing part 4 gradually increases from the outer peripheral end O toward the inner peripheral direction in a curved manner to the A1-A2 position, and is linear from the A1-A2 position to the B1-B2 position. The wall thickness suddenly increases. As a step from the B1-B2 position to the C1-C2 position, the distance further increases rapidly. From the C1-C2 position to the D1-D2 position, the inner peripheral side end portion 5 is formed in a blunt airfoil by linearly expanding again.
[0013]
By adopting such a shape, the step from the B1-B2 position to the C1-C2 position can be further reduced as compared with the conventional technique. As a result, it is possible to suppress the peeling that occurs from the step, and to reduce the turbulence component that occurs from that portion. This leads to improved air flow performance and lower noise.
[0014]
Incidentally, FIG. 4 is an enlarged view of a portion of FIG. 2 according to another embodiment of the present invention. As shown in FIG. 4, 8% to 30% near-Ru stage difference chord length from the inner peripheral edge and (C1-C2 position ~ D1-D2 position), the inclined portions (A1-A2 position ~ B1-B2 position) A plane (B1-B2 position to C1-C2 position) (D1-D2 position to E1-E2 position) may be provided between (E1-E2 position to F1-F2 position) .
[0015]
Before SL stepped portion, For the inclined portion may be provided on both sides of each blade.
[0016]
【The invention's effect】
As apparent from the above-described embodiment, the invention of claim 1 has a high static pressure, so that it is difficult for abnormal sound such as a backlash to occur even if a significant load is applied to the air conditioner body. The flow separation at the inner and outer peripheral portions of the blade is reduced and the air flow performance is improved.
[Brief description of the drawings]
Front view of the cross-flow fan according to the first embodiment of the present invention; FIG 2 shows X1-X2 cross-sectional view of FIG. 1 FIG. 3 a part enlarged view of FIG. 2 and FIG. 4 is another of the present invention Enlarged view of the blade in the embodiment. FIG. 5 is a front view of the cross-flow fan in the prior art. FIG. 6 is a sectional view taken along line X1-X2 in FIG.
1 blade 2 impeller end plate 3 the impeller shaft 4 wing portion 5 inner peripheral end O peripheral end I inner end
A1-A2 position to B1-B2 position Inclined part
B1-B2 position to C1-C2 position Step
C1-C2 position to D1-D2 position inclined part

Claims (1)

  In the cross-flow fan configured by arranging a plurality of blades in an annular shape, the cross-sectional shape of the blades becomes narrower from the inner peripheral side toward the outer peripheral side, and the cross-sectional width of the inner peripheral side end is larger than the cross-sectional width of the main wing part. As shown in the figure, a step substantially perpendicular to the camber line is provided, and an inclined portion is provided at at least one of the corner between the main wing and the step and the corner between the step and the inner peripheral end. Cross-flow fan characterized by that.

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