JPH07180862A - Outdoor machine for air conditioner - Google Patents

Abstract

PURPOSE:To diminish an unstable area taking place on the hub side and thereby to attain reduction of a sound of operation and improvement in efficiency, by accelerating a flow on the hub side. CONSTITUTION:In an outdoor machine for an air conditioner wherein a heat exchanger 2 is disposed on the inlet side of an axial flow fan 1 composed of a plurality of vanes 4 and a hub 5 fixing the vanes 4 and an outlet grille 3 not being axially symmetric is disposed on/the outlet side, the rear-end outside diameter Dh2 of the hub 5 is made larger than the front-end outside diameter Dh1 thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outdoor unit for an air conditioner, and more particularly to an improvement of an axial fan used in an outdoor unit for an air conditioner.

[0002]

2. Description of the Related Art As shown in FIG. 16, a conventional outdoor unit for an air conditioner has a plurality of blades 4 ', 4'.
Axial fan 1'comprising hub 5'for fixing 4 '...
The heat exchanger 2'is arranged on the suction side and the blowing grille 3'is arranged on the blowing side. Reference numeral 6'is a fan guide,
7'is a partition plate and 8'is a fan motor.

In the case of the axial fan 1'used in the outdoor unit for an air conditioner having the above structure, it is operated in the medium air volume range due to the presence of the heat exchanger 2'disposed on the suction side. Since the main flow direction of the blowout flow W is a diagonal flow inclining toward the radial direction in the vicinity of the point of use, due to collision with the front end of the hub 5 ′, from the blade front edge side to the rear edge side on the hub 5 ′ side. There was an unstable region E that expanded.

Further, as an outlet grill 3'in the outdoor unit for an air conditioner, a non-axisymmetric one shown in FIG. 17 (that is,
(Grid grill) may be used, but in this case,
Since the blowout flow W of the single axial fan 1'is substantially axisymmetric, each blade 4'has a portion X where the blowout flow W and the blowout grill 3'are likely to interfere with each other during one rotation. By alternately passing Y and Y, the blowout flow W becomes an unsteady state. Along with this, the unstable region E existing on the hub 5 ′ side also repeats expansion (see FIG. 18A) and contraction (see FIG. 18B), and the pressure fluctuation on the blade surface is very large. Become. Therefore, there has been a problem that the operating noise of the outdoor unit is increased and the efficiency is lowered. Further, the non-uniform axial flow velocity distribution due to the reduction of the flow velocity on the hub 5'side also causes a noise increase.

In order to prevent the occurrence of the unstable region on the hub side as described above, there is disclosed in JP-A-3-23397, a hub using a hub having a shape capable of intentionally separating the flow on the hub side. There is.

[0006]

However, in the above-mentioned known example, the flow before and after the fan is centripetal, and it is considered that it is used in a large air volume range. However, as described above, in the case of the axial fan used in the outdoor unit for the air conditioner, since it is operated in the medium air volume range due to the resistance of the flow path, it becomes a diagonal flow in the radial direction. It is not possible to expect the effects of this technology.

The present invention has been made in view of the above points, and by accelerating the flow on the hub side, the unstable region occurring on the hub side is suppressed to a small level, thereby reducing the operating noise and increasing the efficiency. The purpose is also to improve.

[0008]

In the invention of claim 1, as a means for solving the above-mentioned problems, as shown in the drawings, a plurality of blades 4, 4, ... The heat exchanger 2 is provided on the suction side of the axial fan 1 including the hub 5 to be fixed.
In the outdoor unit for an air conditioner in which the non-axisymmetric blowout grill 3 is arranged on the blowout side, the rear end outer diameter Dh ₂ of the hub 5 is made larger than the front end outer diameter Dh ₁ .

According to a second aspect of the present invention, as means for solving the above-mentioned problems, as shown in the drawings, in the outdoor unit for an air conditioner according to the first aspect, the front end surface 5a of the hub 5 is fixed to the blade 4 The front edge root portion 4a ₁ is projected forward and the outer peripheral portion is formed in a smooth arc.

In the invention of claim 3, as a means for solving the above problems, as shown in the drawings, in the outdoor unit for an air conditioner according to claim 1, the front end surface 5 of the hub 5 is used.
The a is formed into a substantially hemispherical shape that protrudes forward from the front edge root portion 4a ₁ of the blade 4.

In the invention of claim 4, as means for solving the above-mentioned problems, as shown in the drawings, said claim 1,
In the outdoor unit for an air conditioner described in 2 or 3, the rear end surface 5b of the hub 5 is made to project rearward from the rear edge root portion 4b ₁ of the blade 4.

In the invention of claim 5, as means for solving the above-mentioned problems, as shown in the drawings, the above-mentioned claim 1,
In the outdoor unit for an air conditioner according to 2, 3, or 4,
The front end outer diameter and the rear end outer diameter of the hub 5 are set to Dh ₁ and D
When h ₂ and the outer diameter of the blade are D, a = (Dh ₂ −Dh ₁ ) /
(D-Dh ₁ ), 0.05 ≦ a ≦ 0.25.

[0013]

According to the first aspect of the invention, the following actions can be obtained by the above means.

That is, the rear end outer diameter Dh ₂ of the hub 5 is changed to the front end outer diameter Dh.
By making it larger than h ₁ , the flow passage cross-sectional area becomes smaller on the trailing edge 4b side than on the blade leading edge 4a side, the flow velocity on the hub 5 side is accelerated, and the unstable region is suppressed to a small value. The distribution will also be made uniform.

According to the second aspect of the invention, the following effects can be obtained by the above means.

That is, the front end surface 5a of the hub 5 is projected forward from the front edge root portion 4a ₁ of the blade 4, and the outer peripheral portion is formed by a smooth arc, so that the suction on the hub 5 side is performed. Guided by the arc-shaped part, it becomes smooth.

According to the third aspect of the invention, the following actions can be obtained by the above means.

That is, since the front end surface 5a of the hub 5 is formed into a substantially hemispherical shape which projects forward from the front edge root portion 4a ₁ of the blade 4, the suction on the hub 5 side is guided to the substantially hemispherical portion and smoothed. become.

According to the invention of claim 4, the following effects can be obtained by the above means.

That is, by making the rear end surface 5b of the hub 5 project rearward from the rear edge root portion 4b ₁ of the blade 4, it is possible to further accelerate the hub 5 on the outlet side of the blade 4. Become.

According to the invention of claim 5, the following effects can be obtained by the above means.

That is, when the outer diameters of the front end and the rear end of the hub 5 are Dh ₁ and Dh ₂ and the outer diameter of the blades is D, a = (D
By setting so that h ₂ −Dh ₁ ) / (D−Dh ₁ ), 0.05 ≦ a ≦ 0.25, the flow passage cross-sectional area on the leading edge 4a side and the trailing edge 4b side of the blade 4 is set. Is optimized, and as a result, the acceleration on the hub 5 side is also optimized. By the way,
In the case of a <0.05, there is no difference from the conventional axial fan (that is, the axial fan having a cylindrical hub), and the unstable region becomes large. In the case of a> 0.25, There is a possibility that the flow passage cross-sectional area on the trailing edge side of the blade 4 becomes too small and the resistance increases.

[0023]

According to the first aspect of the present invention, the heat exchanger is provided on the suction side of the axial flow fan 1 including the plurality of blades 4, 4, ... And the hub 5 for fixing the blades 4, 4. 2 is an outdoor unit for an air conditioner in which a non-axisymmetric outlet grill 3 is arranged on the outlet side, the rear end outer diameter Dh ₂ of the hub 5 is made larger than the front end outer diameter Dh ₁ , and the flow passage cross-sectional area is Trailing edge 4b from front edge 4a side of blade 4
Since it is made smaller on the side, the flow velocity on the hub 5 side is accelerated, the unstable region is suppressed to be small, and the flow velocity distribution is made uniform, which greatly contributes to the reduction of operating noise and the improvement of efficiency. It has an excellent effect.

According to the second aspect of the present invention, in the outdoor unit for an air conditioner according to the first aspect, the front end surface 5a of the hub 5 is made to project forward from the front edge root portion 4a ₁ of the blade 4, and the outer periphery thereof is formed. Since the portion is formed by a smooth arc, the suction on the hub 5 side is guided by the arc-shaped portion and becomes smooth, which has an excellent effect of greatly reducing the driving noise and improving efficiency.

According to the third aspect of the invention, in the outdoor unit for an air conditioner according to the first aspect, the front end surface 5a of the hub 5 has a substantially hemispherical shape that protrudes forward from the front edge root portion 4a ₁ of the blade 4. Therefore, the suction on the hub 5 side is guided and smoothed in the substantially hemispherical portion, and there is an excellent effect that it greatly contributes to a reduction in operating noise and an improvement in efficiency.

According to the invention of claim 4, in the outdoor unit for an air conditioner according to claim 1, 2 or 3, the rear end surface 5b of the hub 5 projects rearward from the rear edge root portion 4b ₁ of the blade 4. Since it is made possible, the acceleration of the hub 5 side at the outlet side of the blade 4 can be further obtained, which has an excellent effect of greatly contributing to the reduction of operating noise and the improvement of efficiency.

According to the invention of claim 5, in the outdoor unit for an air conditioner according to claim 1, 2, 3 or 4, the front end outer diameter and the rear end outer diameter of the hub 5 are Dh ₁ and D.
When h ₂ and the outer diameter of the blade 4 are D, a = (Dh ₂ −Dh ₁ )
/ (D-Dh ₁ ), 0.05 ≦ a ≦ 0.25, so that the ratio of the flow passage cross-sectional areas on the leading edge 4a side and the trailing edge 4b side of the blade 4 is in the optimum state. As a result, the acceleration on the hub 5 side is also in an optimum state, and there is an excellent effect that it is optimum for reducing operating noise and improving efficiency.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

Embodiment 1 FIGS. 1 and 2 show an outdoor unit for an air conditioner according to Embodiment 1 of the present invention. In this embodiment, claim 1
And 5 corresponds to the invention.

The outdoor unit for an air conditioner of this embodiment also has the same basic structure as that of the conventional one (shown in FIG. 16), and a plurality of blades 4, 4, ... And the blades 4, 4 ,. The heat exchanger 2 is arranged on the suction side of the axial fan 1 composed of the hub 5 to be fixed, and the blowing grill 3 is arranged on the blowing side. In the case of the present embodiment, a non-axisymmetric one (for example, a lattice grill) is used as the blowout grill 3 (see FIG. 2). Reference numeral 6 is a fan guide, 7 is a partition plate, and 8 is a fan motor.

Therefore, the hub 5 of the axial fan 1 has a truncated cone shape whose rear end outer diameter Dh ₂ is larger than its front end outer diameter Dh ₁ . When the outer diameter of the blade 4 is D, a = (Dh ₂ −Dh ₁ ) / D−Dh ₁ ), 0.05 ≦ a ≦
It is desirable to set it to 0.25.

The air conditioner outdoor unit configured as described above has the following effects.

The blowout flow W in the axial fan 1 becomes an oblique flow inclined toward the radial direction, and the flow velocity on the hub 5 side tends to decrease, but the rear end outer diameter Dh ₂ of the hub 5 is set outside the front end. By making the diameter larger than the diameter Dh _1, the flow on the hub 5 side is accelerated, and the unstable region that has conventionally occurred on the hub 5 side can be suppressed to a small value. In addition, the acceleration on the hub 5 side also improves the axial flow velocity distribution.

Further, the repeated expansion and contraction of the unstable region, which has been conventionally caused by the existence of the non-axisymmetric blowout grill 3, does not lead to an increase in noise because the unstable region is suppressed to a small value.

In FIG. 14, the air volume coefficient φ and the specific noise KSA (d
BA) is shown, but in the case of this example (dotted line), not only the minimum specific noise is lower than the conventional example (chain line), but also the bottom before and after the minimum specific noise is wide and the operating point is The specific noise on the lower air volume side than P is lower than that of the conventional example. Therefore, the increase in noise during frost in winter can be suppressed as compared with the conventional example.

FIG. 15 shows the coefficient a and the minimum specific noise KSAmin.
According to this, it is found that 0.05 ≦
It can be seen that the optimum state is realized in the range of a ≦ 0.25. By the way, in the case of a <0.05, there is no difference from the conventional axial flow fan (that is, the axial flow fan having the cylindrical hub), and the unstable region becomes large, and a> 0.25
In this case, the flow passage cross-sectional area on the trailing edge side of the blade 4 becomes too small, which may increase resistance.

Embodiment 2 FIG. 3 shows an axial flow fan used in an outdoor unit for an air conditioner according to Embodiment 2 of the present invention. The present embodiment corresponds to the inventions of claims 1, 4 and 5.

In the case of this embodiment, the rear end surface 5b of the hub 5 is made to project rearward from the rear edge root portion 4b _{1 of the} blade 4. Since other configurations are the same as those in the first embodiment, the description will be omitted to avoid duplication.

Due to the above configuration, the blade 4
Therefore, the acceleration on the hub 5 side at the exit side can be further obtained. Other functions and effects are similar to those of the first embodiment.

Embodiment 3 FIG. 4 shows an axial flow fan used in an outdoor unit for an air conditioner according to Embodiment 3 of the present invention. The present embodiment corresponds to the inventions of claims 1, 4 and 5.

In the case of this embodiment, the rear end surface 5b of the hub 5 is made to project rearward from the rear edge root portion 4b _{1 of the} blade 4 as in the case of the second embodiment. A concave curved surface R extending from the edge root portion 4b ₁ to the rear end surface 5b
Are formed. Other configurations, functions and effects are the same as those of the second embodiment, and the description thereof will be omitted to avoid duplication.

Embodiment 4 FIG. 5 shows an axial fan used in an outdoor unit for an air conditioner according to Embodiment 4 of the present invention. The present embodiment corresponds to the inventions of claims 1, 4 and 5.

This embodiment is similar to the second embodiment in that the rear end surface 5b of the hub 5 is projected rearward from the rear edge root portion 4b _{1 of the} blade 4, but the entire side surface of the hub 5 is provided. Is a concave curved surface R. Other configurations, functions and effects are the same as those of the second embodiment, and the description thereof will be omitted to avoid duplication.

Embodiment 5 FIG. 6 shows an axial flow fan used in an outdoor unit for an air conditioner according to Embodiment 5 of the present invention. The present embodiment corresponds to the inventions of claims 1, 4 and 5.

In the case of this embodiment, the hub 5 has a cylindrical portion 5c from the blade leading edge root portion 4a ₁ to the blade trailing edge root portion 4b _1.
When is configured on the wing trailing edge root portion 4b ₁ outwardly formed over the rear surface 5b of by the convex arc-shaped portion 5d. With this configuration, the cavity flow Wc is generated in the rotating triangular portion formed by the cylindrical portion 5c and the arc-shaped portion 5d of the hub 5, and the flow outside the cavity flow Wc becomes smooth. Other configurations, functions and effects are the same as those of the first embodiment, and the description will be omitted to avoid duplication.

Sixth Embodiment FIG. 7 shows an axial flow fan used in an outdoor unit for an air conditioner according to a sixth embodiment of the present invention. The present embodiment corresponds to the inventions of claims 1, 4 and 5.

In the case of the present embodiment, the cylindrical portion 5c and the arcuate portion 5d of the hub 5 of the fifth embodiment are formed into a smooth curved surface 5e.
It is made continuous with. Also in this case, the same effect as that of the fifth embodiment can be obtained. Other configurations, functions and effects are the same as those of the first embodiment, and the description will be omitted to avoid duplication.

Embodiment 7 FIG. 8 shows an axial flow fan used in an outdoor unit for an air conditioner according to Embodiment 7 of the present invention. The present embodiment corresponds to the inventions of claims 1, 2 and 5.

[0049] In the present embodiment, together with allowed to protrude forward from the blade front end surface 5a of the hub 5 of the front edge root portion 4a ₁ Example 1 to form the outer peripheral portion in a smooth arc. With this configuration, the suction on the hub 5 side is guided by the arc-shaped portion and becomes smooth. In this case, the specific noise is almost the same as that of the first embodiment as shown by the solid line in FIG. Other configurations, functions and effects are the same as those of the first embodiment, and the description will be omitted to avoid duplication.

Embodiment 8 FIG. 9 shows an axial flow fan used in an outdoor unit for an air conditioner according to Embodiment 8 of the present invention. The present embodiment corresponds to the inventions of claims 1, 2, 4 and 5.

In the case of this embodiment, the same shaped portion as that of the seventh embodiment is formed on the front portion of the hub 5 of the third embodiment. Therefore, the same effects as those in the third and seventh embodiments can be expected.

Ninth Embodiment FIG. 10 shows an axial flow fan used in an outdoor unit for an air conditioner according to a ninth embodiment of the present invention. The present embodiment corresponds to the inventions of claims 1, 3, 4 and 5.

In the case of this embodiment, the front end surface 5a of the hub 5 of the third embodiment has a substantially hemispherical shape which projects forward from the blade front edge root portion 4a ₁ . With this configuration, the hub 5
The suction on the side is guided by the hemispherical portion and becomes smooth. Other configurations, functions, and effects are the same as those in the third embodiment, and the description thereof will be omitted to avoid duplication.

Embodiment 10 FIG. 11 shows an axial flow fan used in an outdoor unit for an air conditioner according to Embodiment 10 of the present invention. The present embodiment corresponds to the inventions of claims 1, 2, 4 and 5.

In the case of this embodiment, the same shaped portion as that of the seventh embodiment is formed on the front portion of the hub 5 of the fourth embodiment. Therefore, the same effects as those in the fourth and seventh embodiments can be expected.

Embodiment 11 FIG. 12 shows an axial flow fan used in an outdoor unit for an air conditioner according to Embodiment 11 of the present invention. The present embodiment corresponds to the inventions of claims 1, 2, 4 and 5.

In the case of this embodiment, the same shaped portion as that of the seventh embodiment is formed on the front portion of the hub 5 of the fifth embodiment. Therefore, the same effects as those in the fifth and seventh embodiments can be expected.

Embodiment 12 FIG. 13 shows an axial flow fan used in an outdoor unit for an air conditioner according to Embodiment 12 of the present invention. The present embodiment corresponds to the inventions of claims 1, 2, 4 and 5.

In the case of this embodiment, the same shaped portion as that of the ninth embodiment is formed on the front portion of the hub 5 of the sixth embodiment. Therefore, the same effects as those in the sixth and ninth embodiments can be expected.

The invention of the present application is not limited to the configuration of each of the above-described embodiments, and it goes without saying that the design can be appropriately changed without departing from the gist of the invention.

[Brief description of drawings]

FIG. 1 is a cross-sectional plan view of an outdoor unit for an air conditioner according to a first embodiment of the present invention.

FIG. 2 is a partial front view of the blowout grill in the outdoor unit for an air conditioner according to the first embodiment of the present invention.

FIG. 3 is a vertical cross-sectional side view of an axial flow fan used in an outdoor unit for an air conditioner according to a second embodiment of the present invention.

FIG. 4 is a vertical cross-sectional side view of an axial flow fan used in an outdoor unit for an air conditioner according to a third embodiment of the present invention.

FIG. 5 is a vertical cross-sectional side view of an axial flow fan used for an outdoor unit for an air conditioner according to a fourth embodiment of the present invention.

FIG. 6 is a vertical cross-sectional side view of an axial flow fan used in an outdoor unit for an air conditioner according to a fifth embodiment of the present invention.

FIG. 7 is a vertical cross-sectional side view of an axial fan used for an outdoor unit for an air conditioner according to a sixth embodiment of the present invention.

FIG. 8 is a vertical cross-sectional side view of an axial fan used in an outdoor unit for an air conditioner according to a seventh embodiment of the present invention.

FIG. 9 is a vertical cross-sectional side view of an axial flow fan used in an outdoor unit for an air conditioner according to Embodiment 8 of the present invention.

FIG. 10 is a vertical cross-sectional side view of an axial fan used in an outdoor unit for an air conditioner according to a ninth embodiment of the present invention.

FIG. 11 is a vertical cross-sectional side view of an axial fan used in the outdoor unit for an air conditioner according to Embodiment 10 of the present invention.

FIG. 12 is a vertical cross-sectional side view of an axial fan used in an outdoor unit for an air conditioner according to Example 11 of the present invention.

FIG. 13 is a vertical cross-sectional side view of an axial fan used in an outdoor unit for an air conditioner according to a twelfth embodiment of the present invention.

FIG. 14 is a characteristic diagram showing changes in the specific noise KSA (dBA) with respect to the air volume coefficient φ, together with the conventional example and Examples 1 and 2.

FIG. 15 is a characteristic diagram showing changes in the minimum specific noise KSAmin with respect to the coefficient a in the first embodiment.

FIG. 16 is a cross-sectional plan view of a conventional air conditioner outdoor unit.

FIG. 17 is a partial front view of an outlet grill in a conventional outdoor unit for an air conditioner.

18 (a) and 18 (b) are explanatory views showing unstable regions in the X portion and the Y portion in FIG.

[Explanation of symbols]

1 axial fan 2 is the heat exchanger, the outlet grille 3, the blade, 4a leading edge, 4a ₁ leading edge root portion, 4b is rear edge 4, 4b ₁
Is a rear edge root part, 5 is a hub, 5a is a front end face, 5b is a rear end face,
5c is a cylindrical shape, 5d is an arc shape part, Dh ₁ is the front end outer diameter,
Dh ₂ is the rear end outer diameter, D is the blade outer diameter, and a is the coefficient.

Claims (5)

[Claims] 1. A plurality of blades (4), (4) ... And said blades
The heat exchanger (2) is provided on the suction side of the axial fan (1) consisting of the hub (5) fixing the (4), (4), ... And the non-axisymmetric blow-out grill (3) is provided on the blow-out side. An outdoor unit for an air conditioner arranged, wherein the rear end outer diameter (Dh ₂ ) of the hub (5) is larger than the front end outer diameter (Dh ₁ ). Machine. 2. The front end surface (5a) of the hub (5) has blades (4).
It is projected forward from the front edge root part (4a ₁ ) of
The outdoor unit for an air conditioner according to claim 1, wherein the outer peripheral portion is formed by a smooth arc. 3. The front end surface (5a) of the hub (5) has blades (4).
The outdoor unit for an air conditioner according to claim 1, wherein the outdoor unit for an air conditioner has a substantially hemispherical shape protruding forward from a front edge root portion (4a ₁ ) of the. 4. The blade (4) has a rear end surface (5b) of the hub (5).
The outdoor unit for an air conditioner according to claim 1, 2 or 3, wherein the outdoor unit protrudes rearward from a rear edge root portion (4b ₁ ). 5. When the outer diameters of the front end and the rear end of the hub (5) are Dh ₁ and Dh ₂ and the outer diameter of the blade is D, a =
_{(Dh 2 -Dh 1) / (} D-Dh 1), air in the claim 1, 2, 3 or 4, wherein it is set such that 0.05 ≦ a ≦ 0.25 An outdoor unit for a harmony machine.