JP2956566B2 - Impeller for blower - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an impeller for a blower.

[0002]

2. Description of the Related Art A blade such as an axial flow fan or a mixed flow fan employed in an air conditioner blower generally employs a thin blade structure as shown in FIG. Then, in order to suppress the separation at the leading edge 1A and the separation at the trailing edge 1B, the thin blade 1 is subjected to a leading edge side negative pressure surface cut and a trailing edge side negative pressure surface cut.

[0003] However, in such a case, the leading edge side edge portion causes peeling on the leading edge 1A side negative pressure surface side at the time of medium and low air flow (see FIG. 27), and at the time of large air flow, the leading edge 1A side pressure surface side. Peeling occurs (see FIG. 28), causing strong pressure fluctuations, lowering the air blowing performance and causing aerodynamic noise.

To solve such a problem, for example, an airfoil-structured wing 2 as shown in FIGS.
It is conceivable that this configuration eliminates the flaking on both sides of the leading edge as described above.
There is a problem that the overall thickness is increased, the weight of the blade itself is increased, the cost is increased, and the required driving force is increased.

According to the present invention, the separation of the leading edge side negative pressure surface under the small and medium airflow and the leading edge side pressure under the large airflow can be achieved at low weight and low cost without employing the above-described airfoil blade structure. It is an object of the present invention to provide an impeller for a blower that can prevent peeling on the surface.

[0006]

Means for Solving the Problems In order to achieve the above object, the impeller for a blower of the present invention is provided with the following means for solving the problems.

That is, the impeller for a blower of the present invention is
For example, as shown in FIGS. 1 to 9, a plurality of thin plate-shaped blades 11, 11.
In the impeller for a blower configured to blow in the axial flow direction or the diagonal flow direction by the rotation of 1, 11,..., Each of the thin plate-shaped blades 11, 11,.
In the side pressure surface portion, there is provided a thick portion 12 which bulges out from a front edge to a pressure surface 11b side by drawing a curved surface having a predetermined curvature, and a rear surface of the thick portion 12 is gradually S-shaped toward the rear edge 11c. It is continuous with the pressure surface 11b in a shape of a curve.

The impeller for a blower according to the present invention has a leading edge side negative pressure surface and a pressure surface side thickness formed at the leading edge 11a side extended end of the pressure surface 11b of each blade 11, 11,... A continuous surface with the surface of the portion 12 is formed as a substantially circular arc surface having a predetermined radius of curvature.

The impeller for a blower according to the present invention comprises a front edge 11a and a rear edge 11c of each of the blades 11, 11,...
Are formed in a surface shape substantially close to the cut surface.

In the impeller for a blower according to the present invention, the thick portion 12 is provided in a hollow area on the front edge side from the hub 10 side to the tip side.

[0011]

The blower impeller according to the present invention has the following effects corresponding to the above-described configuration.

That is, first, in the configuration of the impeller for the blower of the present invention, as described above, a plurality of thin plate-type blades 11, 11,... Are provided on the outer periphery of the hub 10, and the blades 11, 1,.
In the impeller for a blower configured to blow air in the axial flow direction or the diagonal flow direction by rotation of the thin plate-type blades, the thin plate-shaped blades 11, 11,. , A curved surface with a predetermined radius of curvature is drawn from the leading edge to the pressure surface 11b side, and further, the rear surface 12b draws a gentle S-shaped curve, and the pressure surface 11b moves toward the trailing edge.
The thick portion 12 swells so as to be continuous.

Therefore, in this configuration, for example, when the air volume is medium or small, a stagnation point of the flow that has flowed into the impeller is formed at a position substantially above the thick portion 12, and the upstream side thereof is round. As a result, the flow entering the negative pressure surface 11d side becomes a smooth flow due to the Coander effect (FIG. 8).
reference).

As a result, the peeling at the negative pressure surface portion on the leading edge 11a side is greatly reduced, whereby the blowing performance is reduced and the noise is considerably improved.

On the other hand, when the air flow is large, a stagnation point of the flow flowing into the impeller is formed on the negative pressure surface 11d side, while the pressure surface 11
The flow flowing into the b side is a smooth flow from the round surface of the thick portion 12 along the S-shaped surface (see FIG. 9).

As a result, the peeling on the side of the pressure surface 11b is eliminated, thereby lowering the blowing performance and considerably improving the noise.

As a result, the air blowing performance and the noise performance are improved over the entire operation range of the impeller.

[0018]

As described above, according to the impeller for a blower of the present invention, it is possible to realize a blower having high blowing performance and silent performance.

[0019]

(Embodiment 1) FIGS. 1 to 9 show the configuration and operation of an impeller for a blower according to Embodiment 1 of the present invention.

FIG. 1 shows a front view of the impeller for the blower. In the drawing, reference numeral 10 denotes a substantially cylindrical hub,
On the outer periphery of the hub 10, a plurality of (four) thin-plate-type blades (wings) 11, 11,... Are provided at a predetermined pitch with a predetermined inclination angle in the blowing direction.

Each of the blades 11, 11,... Has a curved surface having a predetermined curvature from the front edge 11a to the pressure surface 11b at the front edge 11a side pressure surface portion, as shown in FIGS. A thick portion 12 which swells out is provided. As shown in FIG. 12 of an embodiment described later, for example, the thick portion 12 is located in a cutting area on the front edge 11a portion side from the hub mounting end side to the tip end side of the blade 11. Is provided. A continuous surface 12a on the leading edge 11a side and the negative pressure surface 11d side formed at the pressure surface extension end of the thick portion 12 is formed in a substantially positive arc surface with a radius R (see FIG. 7). While the pressure surface 11b side rear surface 1
2b draws a gentle S-shaped curve toward the trailing edge of the blade 11 and smoothly continues to the pressure surface.

Each of the negative pressure surfaces on the leading edge 11a side and the trailing edge 11c side of the blade 11 is formed in a gentle curved shape substantially similar to a conventional cut surface.

Therefore, in the above configuration, for example,
When the air flow is small, the stagnation point of the flow that has flowed into the impeller is formed at a position substantially above the thick portion 12, and the upstream side thereof is an arc surface having an arc surface with a radius R. As a result, the flow entering the negative pressure surface 11d side due to the co-under effect is smooth (see FIG. 8).

As a result, the peeling at the negative pressure surface portion on the leading edge 11a side is greatly reduced, whereby the blowing performance is reduced and the noise is considerably improved.

On the other hand, when the air flow is large, a stagnation point of the flow flowing into the impeller is formed on the negative pressure surface side, while the flow flowing on the pressure surface side is smooth from the round surface of the thick portion 12 along the S-shaped surface. (See FIG. 9).

As a result, the peeling on the pressure surface side is eliminated, thereby lowering the blowing performance and considerably improving the noise.

As a result, the air blowing performance and the noise performance are improved over the entire operation range of the impeller.

(Embodiment 1) Next, FIGS. 11 and 12 show Embodiment 1 of a blower impeller according to the present invention, which is configured based on Embodiment 1 of the present invention.

That is, first, as a thin-plate type blade which is the basis of the blade 11 of the blower impeller according to the first embodiment of the present invention, as shown in FIG. 10, for example, the blade 1 of the impeller of FIG.
1 at the average radius (N = 4) and the chord length (2
26mm), angle of attack (14 °), thickness (3.1mm),
The cut surface R of the leading edge negative pressure surface (R = 7), the cut surface R of the trailing edge negative pressure surface (R = 22), the width of the leading edge edge portion (0.5 m)
m) is adopted. Then, the thick portion 12 having the above-described configuration is provided in a dimensional relationship as shown in FIG. And the thick part 12
Is set to about 1/10 of the chord length (22.4 mm).

The installation position of the thick portion 12 is shown in FIG.
As shown in the figure, the base of the blade 11 on the hub 10 side (root)
From R = Rh (the radius of the hub 10), Re = Rh + (0.7
5 to 0.9) (Rt-Rh). In addition,
Rt is the radius of the impeller. This is a region including the cut area on the substantially front edge 11a side.

B / L = 10%, T / L = 3.3
%, Lt / L = 3.1%, and R = 0.27T.

T is the thickness including the thick portion 12, and B is the thick portion 1
2, L is the chord length, and Lt is the distance from the leading edge of the maximum thickness portion.

(Test Results) First, FIGS. 13 to 15 show the noise reduction effect of the blower impeller having the structure of the first embodiment in comparison with the conventional example. As is clear from the results of these tests, it can be seen that in the configuration of the present embodiment, the blowing performance is improved and the noise is reduced.

FIG. 16 shows the noise reduction effect (the amount of noise reduction with respect to the conventional impeller) of the first embodiment.
The relationship is shown in relation to the width B of the thick portion 12 of the a-side pressure surface portion.

According to the result, for example, 3% <B / L <2
It can be seen that the noise reduction effect is very good in the range of 0%, whereas the wall thickness T becomes large when B / L> 20%.
The problem of increased material costs arises.

FIG. 17 shows the effect of the first embodiment in relation to the maximum thickness T of the thick portion 12 of the pressure surface portion on the leading edge 11a side. According to this result, it is understood that the noise reduction effect is very good in the range of 2% <T / L <5%. On the other hand, if T / L> 5%, the swelling becomes too large, causing a problem of an increase in the strength of the blade 11 and an increase in material cost.

FIG. 18 shows the effect of the first embodiment in relation to the position LT (the distance from the front edge) of the maximum thickness T of the thick portion of the pressure surface portion on the front edge 11a side. According to this, 1.5%
At <LT / L <7%, it can be seen that the low noise effect is very good.

FIG. 19 shows the effect of the first embodiment in relation to the radius R of the radius portion at the position of the pressure surface extension end of the leading edge 11a. According to this, 0.15 <R / T
It can be seen that in the range of <0.4, the noise reduction effect is very good, and outside this range, the effect is significantly reduced.

(Embodiment 2) FIG. 20 shows a configuration of an impeller for a blower according to Embodiment 2 of the present invention.

In this configuration, the thick portion 12 similar to that of the first embodiment is formed with a hollow inside, so that an increase in weight is prevented as much as possible. It is.

According to this configuration, the same operation as that of the first embodiment can be realized without increasing the weight of the blade.

(Third Embodiment) FIGS. 21 to 25 show a configuration of an impeller for a blower according to a third embodiment of the present invention.

In the case of the impeller for a blower according to the present embodiment, the basic structure of the blower is the same as that of FIGS. 1 and 2 described above. (Four) thin plate-shaped blades (wings) 11, 11,... Are provided at a predetermined pitch with a predetermined inclination angle in the blowing direction.

Each of the blades 11, 11,... Has a leading edge 11 as shown in FIGS.
In the a-side pressure surface portion, a thick portion 1 swelling by drawing a radius surface having a predetermined curvature from the front edge 11a to the pressure surface 11b side.
2 are provided. However, as shown in FIG. 25 of a second embodiment described later, the thick portion 12 has the front edge from the mounting end (base end) of the blade 11 to the hub 10 to a predetermined length on the tip end side. It is provided continuously over the area including the peeling area on the 11a part side. As shown in FIG. 7, the continuous surface 12a of the leading edge 11a and the negative pressure surface 11d which is formed at the pressure surface extension end of the thick portion 12 is a substantially circular arc surface having a radius R as shown in FIG. On the other hand, the rear surface 12b on the pressure surface 11b side is smoothly connected to the pressure surface in a gentle S-shaped curve toward the rear edge of the blade 11.

Each of the negative pressure surfaces on the leading edge 11a side and the trailing edge 11c side of the blade 11 is formed in a gentle curved shape substantially similar to a conventional cut surface.

Therefore, in the above configuration, the stagnation point of the flow that has flowed into the impeller is located substantially above the thick portion 12 at the time of, for example, a medium / small air volume, as in the first embodiment. The upstream side is a round surface having an arc surface with a radius R, so that the Kounder effect occurs and the flow entering the negative pressure surface 11d becomes a smooth flow (see FIG. 8 described above). ).

As a result, the peeling at the negative pressure surface portion on the leading edge 11a side is greatly reduced, whereby the blowing performance is lowered and the noise is considerably improved.

On the other hand, when the air flow is large, a stagnation point of the flow flowing into the impeller is formed on the negative pressure surface side, while the flow flowing on the pressure surface side is smooth from the round surface of the thick portion 12 along the S-shaped surface. (See FIG. 9 described above).

As a result, the peeling on the pressure surface side is eliminated, thereby lowering the ventilation performance and considerably improving the noise.

As a result, the air blowing performance and the noise performance are improved over the entire operation range of the impeller.

In the case of this configuration, the thick portion 12 is completely continuous from a predetermined position on the tip end side including the stripped area of each of the blades 11, 11. The blades 11, 11
..The rigidity of itself is improved.

Second Embodiment Next, FIG. 25 shows a second embodiment of the blower impeller according to the present invention, which is configured based on the configuration of the third embodiment of the present invention.

That is, first, as a thin plate-type blade which is the basis of the blade 11 of the impeller for a blower according to the second embodiment of the present invention, as shown in FIG. 10 described above, for example, the blade 11 of the impeller of FIG. At the average radius (N = 4)
Chord length (226 mm), angle of attack (14 °), thickness (3.
1 mm), a cut surface R of the leading edge negative pressure surface (R = 7), a cut surface R of the trailing edge negative pressure surface (R = 22), and a front edge width (0.5 mm). Then, based on the thin plate type blades, in the dimensional relationship shown in FIG.
The thick portion 12 having the configuration as shown in FIGS. 21 to 24 is provided. The thick portion 12 is about 1/1 of the chord length.
Set the length to 0 (about 22.4 mm).

The installation position of the thick part 12 is shown in FIG.
As shown in FIG. 5, from the end (joint end) R = Rh (radius of the hub 10) of the blade 11 to the hub 10, Re = Rh
+ (0.75 to 0.9) (Rt-Rh). Rt is the radius of the impeller. This is a region including the cut area on the substantially front edge 11a side.

B / L = 10%, T / L = 3.3
%, Lt / L = 3.1%, and R = 0.27T.

T is the thickness including the thick portion 12, and B is the thick portion 1
2, L is the chord length, and Lt is the distance from the leading edge of the maximum thickness portion.

(Test Results) With the structure of the second embodiment, the same operation and effect as those of the first embodiment shown in FIGS. 13 to 19 can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view of an impeller part of a blower impeller according to Embodiment 1 of the present invention.

FIG. 2 is a top view of the same.

FIG. 3 is a cross-sectional view of the blade at a portion in the radial direction N = 6 in FIG. 1;

FIG. 4 is a cross-sectional view of the blade at a radial direction N = 4 portion in FIG. 1;

FIG. 5 is a sectional view of the blade at a radial direction N = 2 portion in FIG. 1;

FIG. 6 is a sectional view of the blade at a radial direction N = 1 in FIG. 1;

FIG. 7 is an explanatory diagram showing a thick portion installation region in the blade of the impeller for a blower according to Embodiment 1.

FIG. 8 is an explanatory diagram showing the function and effect of the blade in the small and medium air volume region of the impeller for a blower according to Embodiment 1.

FIG. 9 is an explanatory diagram showing the function and effect of the blade in the large air volume region of the impeller for a blower according to Embodiment 1.

FIG. 10 is a cross-sectional view of a thin plate-type blade that is a basic configuration in the configuration of Example 1 based on the configuration of the impeller for a blower according to Embodiment 1 of the present invention.

FIG. 11 is a cross-sectional view illustrating a configuration of a main part of a blade of the impeller for a blower having the configuration of the first embodiment.

FIG. 12 is a front view showing an installation area of a thick part of the blade of the impeller of the first embodiment.

FIG. 13 is a graph showing the air blowing performance of the impeller of Example 1 in comparison with a conventional example.

FIG. 14 is a graph showing the noise performance of the impeller of the first embodiment in comparison with a conventional example.

FIG. 15 is a graph showing the specific noise performance of the impeller of Example 1 in comparison with a conventional example.

FIG. 16 is a graph showing the noise reduction effect of the impeller of Example 1 in relation to the width of the front edge side thick portion.

FIG. 17 is a graph showing the noise reduction effect of the impeller of Example 1 in relation to the maximum thickness of the leading edge side thick portion.

FIG. 18 is a graph showing the noise reduction effect of the impeller of the first embodiment in relation to the maximum thickness position of the thick portion on the front edge side.

FIG. 19 is a graph showing the noise reduction effect of the impeller of Example 1 in relation to the radius of curvature of the radius of curvature of the leading edge side continuous surface.

FIG. 20 is a cross-sectional view of the blades of the impeller for a blower according to Embodiment 2 of the present invention.

FIG. 21 is a sectional view of the impeller for a blower according to Embodiment 3 of the present invention, taken along the radial direction N = 6 in FIG. 1.

FIG. 22 is a cross-sectional view of the impeller for a blower according to Embodiment 3 of the present invention at a radial direction N = 4 portion in FIG. 1.

FIG. 23 is a sectional view of the impeller for a blower according to Embodiment 3 of the present invention, taken along the radial direction N = 2 in FIG. 1.

24 is a sectional view of the impeller for a blower according to Embodiment 3 of the present invention, taken along a radial direction N = 1 in FIG. 1. FIG.

FIG. 25 is an explanatory diagram showing a thick part installation region in Example 2 based on the configuration of the blade of the impeller for a blower according to Embodiment 3 of the present invention.

FIG. 26 is a sectional view of a blade of a conventional fan for an air blower.

FIG. 27 is an explanatory diagram showing a problem at the time of small and medium airflow of the blade of FIG. 26;

FIG. 28 is a diagram showing a problem when the blade of FIG. 26 has a large air volume.

FIG. 29 is a view showing the operation of the blade of the airfoil structure in which the problem of the blade in FIG.

FIG. 30 is a view showing the operation of the blade of the airfoil structure in which the problem of the blade of FIG. 26 is improved, when the air volume is large.

[Explanation of symbols]

10 is a hub, 11 is a blade, 11a is a leading edge, 11b is a pressure surface, 11c is a trailing edge, 11d is a suction surface, 12 is a thick portion, 1
2b is a rear surface.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenjiro Kinoshita 1304 Kanaokacho, Sakai City, Osaka Daikin Industries, Ltd. Sakai Works Kanaoka Factory (56) References JP-A-4-315000 (JP, A) JP-A-4-339200 (JP, A) JP-A-7-4391 (JP, A) JP-A-56-15498 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F04D 29 / 18-29/38

Claims (4)

(57) [Claims] 1. A plurality of thin plate-shaped blades (11), (11)... Are provided on the outer periphery of a hub (10).
In the impeller for a blower configured to blow air in the axial flow direction or the diagonal flow direction by the rotation of (11)..., The thin plate-type blades (11), (11). In the leading edge side pressure surface portion, the pressure surface (11
b) A thick portion (12) swelled by drawing a curved surface having a predetermined curvature toward the side, and a rear surface of the thick portion (12) is provided.
Shows a gentle S-shaped curve toward the trailing edge (11c).
An impeller for a blower, which is drawn and continuous with the pressure surface (11b) . 2. A continuation of a leading edge side negative pressure surface formed on the leading edge side extension end of the pressure surface (11b) of each blade (11), (11). The impeller for a blower according to claim 1, wherein the surface is formed in a substantially circular arc surface having a predetermined radius of curvature. 3. The negative pressure surface portions of the leading edge (11a) and the trailing edge (11c) of each of the blades (11), (11),. The impeller for a blower according to claim 1 or 2, wherein: 4. The blower according to claim 1, wherein the thick portion (12) is provided in a cutout region at a front edge side from the hub (10) side to the tip side. Impeller.