JPH11182495A - Vane of impeller for blower and impeller for blower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a swish and a resonance phenomenon in a vane of hollow structure furnished with a water draining hole. SOLUTION: Each vane 3 of the impeller for a blower is composed of a vane body 21, lid 22, and a hollow part between them, and has a draining hole 22a at the front edge of the peripheral circumference. The draining hole 22a is furnished in the lid 22 and in communication to the outside of the lid 22, and at the time of rotating, the part 23 situated upstream about the rotating direction of the draining hole 22a is positioned outside more than the surface of the draining hole 22a so as to suppress influx of the air.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blade of an impeller for a blower, and more particularly to a blade having a hollow portion inside and a discharge port communicating from the hollow portion to the outside, and an impeller for a blower having the blade.

[0002]

2. Description of the Related Art With respect to the blades of an impeller for a blower, a technique of forming an airfoil cross section (thick blade shape) in order to improve the blowing performance is widely known. When the airfoil shape is adopted, the separation of the airflow is suppressed irrespective of the fluctuation of the inflow angle of the air, so that the air blowing performance is improved as compared with the thin blade.

[0003] As a countermeasure for reducing the drawback of the airfoil-shaped wing, in which the weight of the wing is increased as compared with the thin wing-shaped wing, it is known that the wing has a hollow structure. However, when the wing has a hollow structure, the wing is manufactured by joining two or more shells, or the wing is manufactured by air-assist molding. In the wing manufactured by these methods, a gap is inevitably formed from the outside of the wing to the hollow part to some extent, and when liquid enters the hollow part, freezing or the like causes a rotational imbalance of the impeller.

In order to suppress this drawback, Japanese Patent Application Laid-Open No. 9-88
Japanese Patent Application Publication No. 890 discloses a technique for positively providing a water discharge port from the hollow portion to the outside of the blade, and discharging the intruding water by using centrifugal force during rotation.

[0005]

In the case where the above-mentioned water discharge port is provided on the blade, it is desirable that the position of the water discharge port is a position where water can easily escape regardless of the rotational position of the impeller. For example, many propeller fans have a shape in which the leading edge of the blade is located closer to the outer circumferential side in the rotational direction for the purpose of higher performance, that is, a so-called “forward blade”. In this case, as shown in FIG. It is necessary to provide a water discharge port 122a at the leading edge of the blade 103.

However, at the leading edge of the blade 103, when the impeller rotates, a phenomenon occurs in which the air flowing into the blade 103 once separates on the negative pressure side (upper side in FIG. 9) and adheres again (FIG. 9). (See the gas flow indicated by the two-dot chain line.) Therefore, when the water discharge port 122a is provided on the suction side of the leading edge of the wing 103, the flow of air that re-adheres or the vortex of air due to separation flows into the hollow portion 103c, and the wind noise is generated. It occurs and resonates in the hollow portion 103c. Further, since the pressure side (the lower side in FIG. 9) of the blade 103 must be a smooth surface, it is difficult to provide a water discharge port.

SUMMARY OF THE INVENTION It is an object of the present invention to suppress the phenomenon that air flows into a hollow portion of a wing when the impeller rotates, thereby suppressing wind noise and resonance phenomena. It is in.

[0008]

According to a first aspect of the present invention, there is provided an impeller for a blower including a shell, a hollow portion, and a discharge port. The hollow portion is a space formed inside the shell. The discharge port is provided in the shell and communicates from the hollow portion to the outside of the shell. In this blade, a portion that is upstream in the rotation direction of the outlet during rotation is located outside the surface of the outlet.

When the impeller for a blower having the blade according to the present invention rotates, gas (air) flows relatively to the blade.
Then, the gas flow approaching the wing surface again is generated partially on the wing surface after separation from the wing surface. Here, assuming that a discharge port is provided at a position where a gas (hereinafter, referred to as a re-adhesion gas) approaching the blade surface again at an angle after the separation comes into contact with the blade surface, the gas flows into the hollow portion. Flowing in, wind noise is generated, and resonance occurs in the hollow portion. However, in this case, the portion on the upstream side in the rotation direction of the discharge port at the time of rotation is structured to be located outside the surface of the discharge port, so the position of the wing surface where the reattached gas hits is more than the position of the discharge port On the downstream side, the position where the vortex is generated due to the separation changes, and the phenomenon that gas flows into the hollow portion through the discharge port when the impeller rotates is suppressed, and the wind noise and resonance phenomenon are suppressed.

[0010] The blade of the impeller for a blower according to claim 2 is
A shell, a hollow portion, an outlet, and a projection are provided.
The hollow portion is a space formed inside the shell. The discharge port is provided in the shell and communicates from the hollow portion to the outside of the shell. The projection is located at a portion which is located on the upstream side in the rotation direction of the outlet during rotation, and has a surface outside the surface of the outlet.

In the impeller for a blower, if an exhaust port is provided at a position where the re-adhered gas hits the blade surface, the gas flows into the hollow portion, and a wind noise is generated to resonate in the hollow portion. Would. However, here, a projection having a surface located outside the surface of the discharge port is arranged at a portion on the upstream side in the rotation direction of the discharge port during rotation. For this reason, the position of the wing surface where the reattached gas hits is downstream of the position of the discharge port, the position where the vortex occurs due to separation changes, and the phenomenon that gas flows into the hollow part when the impeller rotates is suppressed. Wind noise and resonance phenomena are suppressed.

[0012] The blade of the impeller for a blower according to claim 3 is:
The wing according to claim 2, wherein the projection is formed integrally with the shell. Here, since the projections are integrally formed as a part of the shell, steps such as separately joining the projections can be omitted. The wing of the impeller for a blower according to claim 4 is the wing according to claim 2 or 3, wherein the protrusion has a smooth hill shape.

In this case, since the projections have a hill shape, the resistance is reduced and the rotation efficiency is improved. The blade of the impeller for a blower according to claim 5 is the blade according to any one of claims 2 to 4, wherein the protrusion has an inclined portion closer to the outlet than an inclined portion farther from the outlet. The shape is steep.

Here, by steepening the inclination of the protrusion near the discharge port, the amount of gas flowing along the surface of the protrusion near the discharge port and flowing into the discharge port is reduced. Therefore, the phenomenon that gas flows into the hollow portion is further suppressed, and wind noise and resonance phenomenon are suppressed. The blade of the impeller for a blower according to claim 6 is the blade according to any one of claims 2 to 5, wherein the protrusion is located forward of the outlet in the rotation direction upstream of the surface of the outlet. It includes the excitement. In addition, the projection includes a portion that is higher than the surface of the discharge port laterally toward the upstream side in the rotation direction of the discharge port.

The flow direction of the gas flowing into the blades of the impeller for a blower is not limited to one direction, and the direction often fluctuates. For example, an L-shaped heat exchanger may be provided in an outdoor unit for an air conditioner.
Since the air is sucked from the surface, the direction of the air flowing into the impeller tends to fluctuate. Here, since the projection includes not only the upstream side in the rotation direction of the discharge port but also a portion that rises from the surface of the discharge port toward the upstream side in the rotation direction, the gas flowing into the blades Even when the flow direction changes, it is possible to suppress the gas from flowing into the outlet.

[0016] The blade of the impeller for a blower according to claim 7 is:
The blade according to claim 1, wherein a surface around the outlet is depressed inward. Then, there is a step between the portion on the upstream side in the rotation direction of the discharge port during rotation and the surface around the discharge port. In this blade, due to the step, the portion that is upstream in the rotation direction of the discharge port during rotation is positioned outside the surface of the discharge port. In addition, by depressing the surface around the discharge port, the generation position and vector of the vortex due to separation are positively changed, and the phenomenon that gas flows into the hollow portion when the impeller rotates is further suppressed.

The blade of the impeller for a blower according to claim 8 is:
A shell, a hollow portion, and an outlet are provided. The hollow portion is a space formed inside the shell. The outlet is
The shell is provided so as to communicate from the hollow portion to the outside of the shell, and is located at a position different from a position where an airflow separates from the surface of the shell during rotation and then collides with the surface of the shell.

When the impeller for a blower having the blade according to the present invention rotates, gas flows relatively to the blade. And
On the surface of the wing, there is a flow of gas that is partially separated from the surface of the shell and then impinges again on the surface of the shell. Here, assuming that a discharge port is provided at a position where a gas (hereinafter, referred to as a re-adhesion gas) approaching the surface of the shell again at an angle after the peeling as described above is provided at a position where the gas comes into contact with the shell surface, the gas flows into the hollow portion. And wind noise is generated, causing resonance in the hollow part. However, in this case, the discharge port is located at a position different from the position where the airflow separates from the surface of the shell during rotation and then collides with the surface of the shell. Deviates from position. Therefore, a phenomenon in which gas flows into the hollow portion through the discharge port when the impeller rotates is suppressed, and wind noise and a resonance phenomenon are suppressed.

[0019] The wing of the impeller for a blower according to claim 9 is:
In the wing according to any one of claims 1 to 8, the outlet is provided at a front edge of the shell. At the leading edge of the wing,
When the impeller rotates, the inflowing air tends to peel off once and adhere again. Therefore, when the impeller rotates by adopting a structure in which the portion on the upstream side in the rotation direction of the discharge port during rotation with respect to the discharge port at the front edge of the shell is located outside the surface of the discharge port. Thus, the effect of suppressing the phenomenon that air flows into the hollow portion of the airfoil and the effect of suppressing the wind noise and the resonance phenomenon are increased.

According to a tenth aspect of the present invention, there is provided an impeller for a blower according to the second aspect, wherein the shell comprises a wing body and a lid. The wing main body includes a surface facing the pressure side. The lid faces the suction side. The projection is formed integrally with the front edge of the wing body. The outlet is provided at the front edge of the lid. Here, the shell has a two-body structure of the wing body and the lid, and the hollow portion is a space formed between the wing body and the lid. The discharge port is provided at least at the front edge of the lid, so that unnecessary foreign matter such as water stays at the front edge of the blade.
Further, since the outlet is provided not on the blade body but on the lid on the suction side, an increase in resistance of the blade due to the presence of the outlet is suppressed to a small level.

According to an eleventh aspect of the present invention, there is provided an impeller for a blower comprising a hub and the blades of the plurality of impellers for the air blower according to any one of the first to tenth aspects. The hub is mounted on a rotating shaft of a drive source. The wings are respectively mounted on the outer periphery of the hub. The impeller for a blower according to the present invention is an impeller having a hollow structure wing provided with a water discharge port and having a high blowing performance and a high rotational balance, and is provided in a hollow portion of the wing when the impeller rotates. The amount of air flowing in is reduced, and wind noise and resonance phenomena are reduced.

[0022]

[First Embodiment] FIG. 1 shows a propeller fan (an impeller for a blower) according to an embodiment of the present invention. The propeller fan 1 is used to blow air in an outdoor unit 10 for an air conditioner as shown in FIGS. 2 and 3.

As shown in FIG. 2, the outdoor unit 10 comprises a heat exchange room 8 and a machine room 9, both of which are separated by a partition plate. The heat exchange room 8 contains the propeller fan 1
Are mounted on a rotating shaft 4a, and a heat exchanger 5 having an L-shaped cross section, and a bar-shaped blowing grill 6 is fitted on the front surface. When the propeller fan 1 is rotated by the motor 4, air passing through the heat exchanger 5 is blown out from the grill 6 along the direction indicated by the two-dot chain line in FIG. 2 and forward of the outdoor unit 10 (the lower side in FIG. 2).
Flows to The propeller fan 1 rotates in the direction of the arrow shown in FIG. The machine room 9 includes a compressor unit 7
And electrical components (not shown) are provided.

The propeller fan 1 has a cylindrical hub 2.
And three blades 3 joined to the outer peripheral surface of the hub 2 at a predetermined inclination angle in the blowing direction. A groove or the like (not shown) is formed in the inner peripheral portion of the hub 2 so as to be non-rotatably fitted with the rotating shaft 4 a of the motor 4. Although the propeller fan 1 having three blades is employed here, a fan having four or five blades may be used.

The wing 3 is a so-called forward wing, and has a shape in which the leading edge advances in the rotational direction toward the outer peripheral side in order to improve aerodynamic performance (see FIGS. 1 and 3). Further, a hollow structure is adopted, and the wing 3 is a thick wing (airfoil-shaped wing) and a lightweight wing. Since the wing 3 is a thick wing, its leading edge is rounded (see FIG. 5).
The degree of separation of airflow (air) flowing from various directions can be reduced, particularly the degree of occurrence of leading edge separation.

Specifically, the wing 3 is constituted by a wing body 21 which is a shell and a lid 22. FIG. 4 is an enlarged plan view of the blade 3, and FIG. 5 is a cross-sectional view of the blade 3. Wing body 2
When the lid 1 and the lid 22 are bonded together by ultrasonic bonding or the like, a hollow portion 3c is formed between the two 21 and 22 (see FIG. 5). As shown in FIG. 5, the wing body 21 has a sectional shape such that a solid wing is provided with a concave portion 21a, and includes a front portion 3a, an intermediate thin portion 21b, and a rear portion 3b. A step 21c is formed around the recess 21a, and the peripheral end of the lid 22 fits into the step 21c. Further, as shown in FIG. 4, the wing main body 21 is formed with positioning projections 21e and 21f projecting from the step 21c. Further, a protrusion 23 swelling toward the negative pressure surface side (upper side in FIG. 7) is integrally formed on the outer peripheral portion of the front portion 3a of the wing main body 21. The protrusion 23 will be described later.

The lid 22 is a thin shell and has a curved shape with a front edge extending forward on the outer peripheral side. Lid 22
The edge of is drawn a smooth curve, but the outer peripheral front edge,
An outer peripheral side leading edge outlet 22a, an outer peripheral side trailing edge outlet 22b, and an inner peripheral side trailing edge outlet 22c are formed at the outer peripheral side rear edge and the inner peripheral side rear edge, respectively (FIG. 1). And FIG. 4). These outlets 22a, 22b, 22c communicate with the outside of the blade 3 from the hollow portion 3c. In addition, the lid 22
The positioning recesses 22d and 22e are formed at substantially the center of the outer peripheral edge and the inner peripheral edge. These recesses 22d and 22e are engaged with the positioning protrusions 21e and 21f when the lid 22 is fitted to the wing body 21.

The projection 23 is formed integrally with the wing body 21 and swells toward the negative pressure surface at the outer peripheral portion of the front portion 3a. The point P shown in FIG. 6 and FIG.
Are shown. The protrusion 23 is located at a portion which is located on the upstream side in the rotation direction of the outer peripheral side front edge discharge port 22a when the propeller fan 1 rotates, and the surface thereof has an outer peripheral side front edge discharge port
It is outside the surface of a. Further, the projection 23 has a smooth hill shape, and the rear inclined surface 23b closer to the outer peripheral side front edge outlet 22a is steeper than the front inclined surface 23a farther from the outer peripheral side front edge outlet 22a. (See FIG. 7). Further, the projection 23 extends not only to the front portion of the outer peripheral side front edge discharge port 22a toward the upstream in the rotational direction, but also to the side portion of the outer peripheral side front edge discharge port 22a toward the upstream in the rotational direction. As a result, it rises higher than the surface of the outer peripheral side front edge discharge port 22a (see FIG. 6).

When the propeller fan 1 of the present embodiment rotates, air flows into the blades 3. Then, on the surface of the wing 3, a gas flow that partially comes off the surface of the wing 3 and then approaches the surface of the wing 3 again is generated. Here, as shown in FIG. 9, assuming that a water discharge port 122 a is provided at a position where air (hereinafter, referred to as re-adhered gas) approaching the surface of the wing 103 at an angle meets the surface of the wing 103. The air flows into the hollow portion 103c, and a wind noise is generated to cause resonance in the hollow portion 103c.

On the other hand, in the blade 3 of the propeller fan 1 according to the present embodiment, the projection 23 is disposed at a portion on the upstream side in the rotation direction of the outer peripheral side front edge discharge port 22a during rotation.
As shown in FIG. 8, the position of the surface of the wing 3 (the position of the surface of the lid 22) where the reattached gas collides with the outer peripheral side front edge outlet 22 a.
8, the position and vector of the eddy current generated by the separation change, the phenomenon that air flows into the hollow portion 3c is suppressed, and the wind noise and the resonance phenomenon are suppressed (see the two-dot chain line in FIG. 8). Air flow shown).

In other words, by forming the projections 23, the outer peripheral side front edge outlet is located at a position different from the position where the airflow collides with the surface of the lid 22 after the propeller fan 1 rotates and separates from the surface of the blade body 21. 22a has been positioned. In addition, since the projections 23 are integrally formed as a part of the wing body 21, a step of joining the projections is not required. Since the projections 23 are formed in a hill, the rotational resistance of the propeller fan 1 is reduced. And rotation efficiency is good.

Further, since the inclination of the rear inclined surface 23b is steeper than that of the front inclined surface 23a, the amount of air flowing along the rear inclined surface 23b and flowing into the outer peripheral side front edge outlet 22a is reduced. . Thereby, the phenomenon that air flows into the hollow portion 30c is further suppressed, and the wind noise and the resonance phenomenon are also suppressed. In addition, the outdoor unit 1 for an air conditioner
0 is provided with an L-shaped heat exchanger 5, and air is sucked in from two surfaces of the heat exchanger 5, so that the direction of the air flowing into the blades 3 tends to fluctuate. On the other hand, in the propeller fan 1 of the present embodiment, the protrusions 23
The flow of the air flowing into the blades 3 includes not only the upstream side in the rotation direction of 2a but also the side toward the upstream side in the rotation direction, which includes a portion rising from the surface of the outer peripheral front edge outlet 22a. Even if the direction changes, the outer peripheral side leading edge outlet 2
The flow of air into 2a can be suppressed.

The lid 22 of the wing 3 has an outer peripheral front edge,
An outer peripheral side front edge outlet 22a, an outer peripheral side trailing edge outlet 22b, and an inner peripheral side trailing edge outlet 22c are formed on the outer peripheral side rear edge and the inner peripheral side rear edge, respectively. Therefore, regardless of the rotational position of the propeller fan 1, the rainwater flowing into the hollow portion 3 c of each blade 3 is easily discharged.
Further, when centrifugal force acts on water in the hollow portion 3c due to the rotation of the propeller fan 1, the water is effectively discharged from the outer peripheral side leading edge outlet 22a and the outer peripheral side trailing edge outlet 22b to the outside of the blade 3.

[Second Embodiment] In the first embodiment,
By forming the projection 23 on the upstream side of the outer peripheral side leading edge discharge port 22a provided at the leading edge of the blade 3 (see FIG. 8 and the like).
Although the inflow of air into the hollow portion 3c is suppressed, the inflow of air into the hollow portion of the blade can be suppressed by the following configuration. The configuration other than the outer peripheral side front edge portion of the blade is the same as that of the first embodiment, and thus the description is omitted.

The wing 30 of the present embodiment employs a hollow structure, and is constituted by a wing body 41 and a lid 42, which are shells, and a hollow portion 30c is formed between the two 41, 42. ). The wing body 41 has a cross-sectional shape such that a concave portion is provided in a solid wing.
1b, and the rear. The peripheral end portion of the lid 42 fits into a step formed on the front side and the rear side of the concave portion.

A concave portion 42f whose surface is concave toward the hollow portion 30c is formed at the outer peripheral side front edge portion of the lid 42.
At the front end of the recess 42f, an outer peripheral side front edge discharge port 42a adjacent to the wing body 41 is formed (see FIG. 10). The outer peripheral side leading edge outlet 42a communicates from the hollow portion 30c to the outside of the blade 30. Wing body 41 and lid 42
Are joined, the leading edge portion of the wing 30 is in a state as shown in FIG. That is, the suction side surface of the leading edge of the blade 30 is more concave than the other surface around the discharge port 42a, the downstream side of the discharge port 42a has a smooth slope, and the upstream side of the discharge port 42a is A steep wall surface (step) 50 is formed by the main body 41. Further, the wall surface 50 extends not only in a front portion toward the upstream side of the outlet 42a but also in a side portion toward the upstream side of the outlet 42a.

When the wing 30 of this embodiment rotates, the wing 30
The air flows relatively to. Then, on the surface of the wing 30, a gas flow that partially comes off the surface of the wing 30 and then approaches the surface of the wing 30 again is generated. Here, as shown in FIG. 9, air (hereinafter, referred to as re-adhered gas) approaching the surface of the blade 103 at an angle is referred to as a blade 10.
Assuming that the water discharge port 122a is provided at a position where the water discharge port 122a comes into contact with the surface of the third surface 3, air flows into the hollow portion 103c,
Wind noise is generated and resonates in the hollow portion 103c.

On the other hand, in the blade 30 of the present embodiment, since the wall surface 50 exists at a portion on the upstream side of the outer peripheral side leading edge discharge port 42a during rotation, as shown in FIG. The position of the surface of the wing 30 (the position of the surface of the lid 42) on the downstream side is located downstream of the position of the outer peripheral side front edge outlet 42a, and the position and vector of the vortex caused by separation due to the presence of the wall surface 50 and the recess 42f. Is positively changed (see the flow of air indicated by the two-dot chain line in FIG. 10), the phenomenon that air flows into the hollow portion 30c is suppressed, and the wind noise and resonance phenomenon are suppressed.

Also, since the inclination of the wall surface 50 is steep,
The amount of air flowing along the wall surface 50 and flowing into the outer peripheral side front edge outlet 42a is reduced. Thereby, the phenomenon that air flows into the hollow portion 30c is further suppressed, and the wind noise and the resonance phenomenon are also suppressed. Further, since the wall surface 50 exists not only on the upstream side of the outer peripheral side front edge discharge port 42a but also on the side toward the upstream side, even when the flow direction of the air flowing into the blade 30 changes, the outer peripheral side is not removed. The flow of air into the leading edge outlet 42a can be suppressed.

[0040]

According to the present invention, the portion of the blade on the upstream side of the discharge port during rotation is located outside the surface of the discharge port. It is on the downstream side from the position, and the position where the vortex is generated by the separation changes, the phenomenon that gas flows into the hollow part through the discharge port when the impeller rotates is suppressed, and the wind noise and resonance phenomenon are suppressed. You.

[Brief description of the drawings]

FIG. 1 is a perspective view of a propeller fan according to an embodiment of the present invention.

FIG. 2 is a cross-sectional plan view of the outdoor unit for an air conditioner.

FIG. 3 is a front view of an outdoor unit for an air conditioner.

FIG. 4 is an enlarged plan view near a wing.

FIG. 5 is a sectional view taken along line VV of FIG. 4;

6 is an enlarged view of VI in FIG. 4;

FIG. 7 is a sectional view taken along line VII-VII of FIG. 6;

FIG. 8 is an airflow diagram at the leading edge of the wing according to the first embodiment.

FIG. 9 is an airflow diagram at the leading edge of a conventional wing.

FIG. 10 is an airflow diagram at a leading edge of a wing according to the second embodiment.

[Explanation of symbols]

 Reference Signs List 1 propeller fan (impeller for blower) 2 hub 3 blade 3a front part (front edge) 3b rear part 3c hollow part 21, 41 blade body (shell) 22, 42 lid (shell) 22a, 42a outer peripheral side front edge outlet (Discharge port) 23 Projection 50 Wall surface (step)

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Takahisa Sueoka 1304 Kanaokacho, Sakai City, Osaka Daikin Industries Inside Kanaoka Plant of Sakai Seisakusho Co., Ltd. (72) Eiichi Kitano 1304 Kanaokacho, Sakai City, Osaka Daikin Industries, Ltd. (72) Inventor Yoshimasa Kikuchi 1304 Kanaokacho, Sakai-shi, Osaka Daikin Industries Kanaoka Plant, Sakai Plant

Claims (11)

[Claims] 1. Shells (21, 22), (41, 42)
And hollow portions (3c) and (30c) formed inside the shells (21, 22) and (41, 42); and the shell (2) from the hollow portions (3c) and (30c).
Outlets (22a) and (42a) provided in the shells (21, 22) and (41, 42), which communicate with the outside of (1, 22) and (41, 42). Portions upstream of the outlets (22a) and (42a) in the rotational direction are the outlets (22a) and (42).
The blades (3) and (30) of the impeller for the blower located outside the surface of a). 2. A shell (21, 22), a hollow part (3c) formed inside the shells (21, 22), and from the hollow part (3c) to the outside of the shells (21, 22). A discharge port (22a) provided in the shells (21, 22), which is in communication with the discharge port (22a); And a projection (23) outside the surface of (3). 3. The projection (23) is provided on the shell (21, 21).
The impeller blade (3) for a blower according to claim 2, which is formed integrally with (2). 4. The blade (3) of an impeller for a blower according to claim 2, wherein the projection (23) has a smooth hill shape. 5. The projection (23) is provided with the discharge port (22).
The inclined portion (23b) on the side closer to a) is the outlet (22).
A blade (3) for an impeller for a blower according to any one of claims 2 to 4, wherein the blade (3) is steeper than the inclined portion (23a) farther from a). 6. The projection (23) is provided with the discharge port (22).
The impeller for a blower according to any one of claims 2 to 5, further comprising a portion that is raised from the surface of the discharge port (22a) forward and laterally toward the upstream side in the rotation direction of (a). Wings (3). 7. A surface around the discharge port (42a) is depressed inward, and a portion between the portion upstream of the discharge port (42a) in the rotation direction during rotation and a surface around the discharge port (42a) is rotated. The fan impeller blade (30) according to claim 1, wherein there is a step (50) between them. 8. Shells (21, 22), (41, 42)
And hollow portions (3c) and (30c) formed inside the shells (21, 22) and (41, 42); and the shell (2) from the hollow portions (3c) and (30c).
(22), (41, 42), and after the airflow separates from the surfaces of the shells (21, 22), (41, 42) during rotation, the shells (21, 22), (4)
(22), (42a) provided at the shell (21, 22), (41, 42) at a position different from the position where the surface collides with the surface of the fan (1, 42). Wings (3), (30). 9. The discharge ports (22a) and (42a) are provided at front edges (3) of the shells (21, 22) and (41, 42).
The blades (3), (3) of the impeller for a blower according to any one of claims 1 to 8, provided in (a) and (30a).
0). 10. The shell (21, 22) comprises a wing body (21) including a surface facing the pressure side, and a lid (22) facing the suction side. 23) The wing body (21) is formed integrally with the front edge of the wing body (21), and the outlet (22a) is provided at the front edge of the lid (22). The blade (3) of the impeller for a blower according to the present invention. 11. A plurality of blowers according to claim 1, wherein a hub (2) is mounted on a rotating shaft (4a) of a drive source, and a plurality of blowers are mounted on an outer periphery of said hub (2). An impeller (1) for a blower, comprising wings (3) and (30) of an impeller.