JP2001140797A - Blower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent separation of an air flow from a guide and suppress deterioration of noise performance when an air passage between the slope of a guide mounted downstream from an impeller and the discharge surface of a fan casing is operated as a diffuser. SOLUTION: A guide 10 situated in the vicinity of an impeller 4 and vertically to the rotary shaft of an impeller 4 and gradually increased in diameter from approximately the same diameter as diameter of the end face, situated downstream, of the hub part 3 of the impeller 4 is mounted in a position situated downstream from the impeller 4. An annular groove 13 having a central axis being the rotary shaft of the impeller 4 is formed in the slope of the guide 10. The groove of the slope of the guide 10 is brought into a negative pressure, an air flow is attracted to the slope of the guide 10, separation of an air flow is suppressed, and deterioration of noise performance is prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blower used for a refrigerator, an air conditioner and the like.

[0002]

2. Description of the Related Art In recent years, blowers have been required to be smaller, have lower noise, and have higher performance.

A conventional blower is disclosed in Japanese Patent Laid-Open No. 63-24 / 1988.
There is one disclosed in Japanese Patent No. 3494.

Hereinafter, the above-described conventional blower will be described with reference to the drawings.

FIG. 8 shows the structure of a conventional blower. In FIG. 8, reference numeral 1 denotes a blower, which is an impeller 4 composed of a blade 2 and a hub portion 3 for performing a boosting and blowing operation, a cone-shaped guide 5, and a first air path member installed on a downstream end face of the guide 5. 6, a fan casing 7, and a second air passage member 8 attached to the outer periphery of the outlet end of the fan casing 7.

The operation of the blower constructed as described above will be described below.

First, air pressurized by the action of the impeller 4 rotated by the motor is supplied to the guide 5 and the first air path member 6.
Accordingly, the air is directed substantially in the radial direction with almost no pressure loss, and is blown out from between the first air passage member 6 and the second air passage member 8. At this time, since the cross-sectional area of the air passage increases toward the downstream side, the air is decelerated and the velocity energy is converted to static pressure.

[0008]

In the above configuration, the guide 5 for controlling the air flow exists immediately after the impeller 4, and the flow is a decelerating flow in which the air flow is easily separated. Unless the dimensions are properly determined, it is difficult to improve the noise performance of the blower.

However, refrigerators and air conditioners are often used under conditions of high air flow resistance due to the product dimensions and the configuration of the product air flow path.

When an axial fan and a diagonal fan are used for the impeller 4 under the condition of high wind path resistance, the radial velocity component of the airflow discharged from the impeller 4 becomes larger than the axial velocity component, and However, it is easy to separate from the guide 5.

Further, since the air path resistance is not stable due to the dew of the heat exchanger incorporated in the product air path, it is very difficult to determine the shape and dimensions of the guide 4, and the air flow is changed along with the air path resistance. However, there has been a problem that vortices are generated by peeling off from the guide 4 and become a noise source.

Further, due to the configuration of the product air path, there is a problem that a specific direction of the air path outlet is sealed or narrowed, and the air blowing performance is reduced.

An object of the present invention is to prevent airflow from separating from a guide in a blower and control deterioration of noise performance.

[0014]

In order to solve this problem, a blower according to the present invention is provided downstream of an impeller of an axial fan or a mixed flow fan, close to the impeller and perpendicular to the rotation axis of the impeller. A guide whose diameter gradually increases from the diameter substantially the same as the diameter of the downstream end face of the hub portion of the impeller toward the downstream;
An air passage is formed by the discharge surface of the fan casing facing the inclined surface of the guide, and the inclined surface of the guide has an annular groove centered on the rotation axis of the impeller.

With this configuration, the inside of the groove on the inclined surface of the guide becomes negative pressure, and the air flow is drawn to the inclined surface of the guide, preventing the air flow from separating and controlling the deterioration of the noise performance.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION
On the downstream side of the impeller of the axial flow fan or the mixed flow fan, installed close to the impeller and perpendicular to the rotation axis of the impeller,
An air path is formed by a guide whose diameter gradually increases downstream from a diameter substantially the same as the diameter of the downstream end surface of the hub portion of the impeller, and a discharge surface of a fan casing facing the inclined surface of the guide. A fan having an annular groove on the inclined surface of the guide with the rotation axis of the impeller as a central axis, and the groove on the inclined surface of the guide becomes negative pressure, and has an effect of attracting airflow to the inclined surface of the guide. .

According to a second aspect of the present invention, the groove of the inclined surface of the guide according to the first aspect of the present invention is passed through the inside of the guide again to the downstream side of the air passage between the guide and the discharge surface of the fan casing. The fan has a function of attracting airflow to the guide inclined surface when the groove on the guide inclined surface becomes negative pressure.

Further, there is also an effect that a part of the air flow forms an auxiliary air passage which enters the guide from the upstream groove and exits from the downstream.

The third aspect of the present invention is the first or second aspect.
This is a blower in which the width of the groove is partially changed, and has a function of attracting airflow to the guide inclined surface when the groove of the guide inclined surface becomes a negative pressure.

Further, the pressure is lower at a place where the groove is wide than at a place where the groove is narrow, so that the air flow at the place where the groove is narrow flows to the place where the groove is wide.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

The same components as in the conventional example are denoted by the same reference numerals to avoid duplication, and description thereof is omitted.

(Embodiment 1) FIGS. 1 to 4 show Embodiment 1 of the present invention.
FIG.

1 to 4, reference numeral 9 denotes a blower, which is installed downstream of the impeller 4 and close to the impeller 4 and perpendicular to the rotation axis of the impeller 4, and downstream of the hub 3 of the impeller 4. An air passage 12 is formed by a frusto-conical guide 10 whose diameter gradually increases downstream from a diameter substantially equal to the diameter of the side end face, and a discharge surface of a fan casing 11 opposed to the inclined surface of the guide 10.
An annular groove 13 having the rotation axis of the impeller 4 as a central axis is provided on the inclined surface of the guide 10.

With this configuration, when the impeller 4 rotates,
The air pressurized by the operation of the impeller 4 is discharged from the fan casing 11 to the air passage 12 formed by the guide 10 and the discharge surface of the fan casing 11.

At this time, the discharged air is supplied to the guide 10
Since the inside of the groove 13 becomes a negative pressure, it is attracted to the groove 13, and it is possible to suppress the air flow from separating from the guide 10 and increase in noise.

In this embodiment, the shape of the guide 10 is a truncated cone. However, as shown in FIG. 3, the portion corresponding to the inclined surface of the cross section of the guide by the plane including the rotation axis of the impeller is the rotation of the impeller. The same effect can be obtained with a guide having a curved curve with a convex radius of curvature toward the axis.

In this embodiment, the groove 13 is provided perpendicular to the rotation axis of the impeller 4, but as shown in FIG.
A similar effect can be obtained even if a groove is provided substantially perpendicularly to the 0 inclined surface.

(Embodiment 2) FIG. 5 shows a blower according to Embodiment 2 of the present invention.

In FIG. 5, reference numeral 14 denotes a blower, which has an annular groove 18 on the inclined surface of the guide 15 with the rotation axis of the impeller 4 as a center axis. The structure returns to the downstream side of the air passage 17 between the fan case 16 and the discharge surface of the fan casing 16.

With this configuration, when the impeller 4 rotates,
The air pressurized by the operation of the impeller 4 is discharged from the fan casing 16 to the air passage 17 formed by the guide 15 and the discharge surface of the fan casing 16.

At this time, a part of the discharged air enters the guide 15 through the groove 18 on the upstream side of the guide 15,
To return to the air path 17 from the downstream groove 18, the upstream groove 1
8 becomes negative pressure, the main flow of the air flow is attracted to the groove 18,
It is possible to prevent the airflow from separating from the guide 15 and increase the noise.

Further, since the air flow entering the guide 15 from the groove 18 on the upstream side of the guide 15 returns to the air path 17 from the downstream side again, the guide blower and the entirety of the guide are not connected at the upstream and downstream sides. Guide 1 even if the air volume of the
The amount of air passing through the air passage 17 between the fan 5 and the fan casing 16 decreases.

As a result, the flow velocity of the air flow is reduced, and the guide 15 and the fan casing 16 acting as a diffuser are reduced.
And the width of the air path 17 between the two can be reduced, and the size of the blower can be reduced. Further, if the widths of the air passages 17 are made equal, the blowing performance can be improved.

(Embodiment 3) FIGS. 6 and 7 show Embodiment 3 of the present invention.
FIG.

6 and 7, reference numeral 19 denotes a blower.
The outlet of the air passage 22 is sealed in a specific direction by an air passage member 23, has a groove 24 on the inclined surface of the guide 20, and has a width of the groove 24 where the outlet of the air passage 22 is open. It has a structure in which the width of the groove is smoothly changed so as to be wide and narrow at the place where it is sealed.

With this configuration, when the impeller 4 rotates,
The air pressurized by the operation of the impeller 4 is discharged from the fan casing 21 to the air passage 22 formed by the guide 20 and the discharge surface of the fan casing 21.

At this time, the discharged air is supplied to the guide 20.
Since the groove 24 becomes negative pressure, the groove 24 is attracted to the groove 24, so that it is possible to suppress the air flow from separating from the guide 20 and increasing the noise.

Further, the groove where the air passage is opened is
Because it is wider than the groove where it is sealed, it becomes more negative pressure and attracts airflow, so that the airflow that goes to the sealed place is directed to the open side and the blowing performance is improved. Can be.

In this embodiment, the wind path is a wind path in which a specific direction of the air path is completely sealed. However, in a wind path in which discharge from the air path is difficult because a part of the air path is narrowed. Has the same effect.

[0041]

As described above, according to the present invention, the hub of the impeller is installed on the downstream side of the impeller of the axial flow fan or the mixed flow fan, close to the impeller and perpendicular to the rotation axis of the impeller. An air path is formed by a guide whose diameter gradually increases downstream from a diameter substantially the same as the diameter of the downstream end surface of the portion, and a discharge surface of the fan casing facing the inclined surface of the guide. By adopting a configuration that has an annular groove with the rotation axis of the impeller as the center axis, even if the airflow resistance changes and the air flow separates from the guide, the guide groove becomes negative pressure The effect of suppressing separation due to attraction of the air flow and suppressing an increase in noise can be obtained.

Further, the guide inclined surface has an annular groove centered on the rotation axis of the impeller, and the groove passes through the inside of the guide again to the downstream side of the air passage between the guide and the discharge surface of the fan casing. By the configuration of returning, even if the airflow resistance changes and the airflow becomes a flow that separates from the guide, part of the discharged air enters the guide from the groove on the upstream side of the guide, To return to the air channel from the downstream groove,
Since the groove becomes negative pressure and attracts airflow, peeling is suppressed,
The effect of suppressing an increase in noise is obtained.

In addition, since the air flow entering the guide from the groove on the upstream side of the guide returns to the air path again from the downstream side, the effect of improving the blowing performance can be obtained.

Further, by providing a groove on the inclined surface of the guide with the rotation axis of the impeller as the center axis and the width of the groove partially changing, the airflow resistance changes and the airflow is reduced. Even if the flow is such that it separates from the guide, the groove of the guide becomes negative pressure and attracts the airflow, so that the effect of suppressing separation and suppressing an increase in noise can be obtained.

Moreover, the groove where the air passage is opened is
Because it is wider than the groove in the sealed place, it becomes more negative pressure and attracts the airflow, so the airflow that goes to the sealed place is directed to the open side and the blowing performance is improved The effect is also obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a blower according to Embodiment 1 of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a sectional view of another blower according to the first embodiment of the present invention.

FIG. 4 is a sectional view of another blower according to the first embodiment of the present invention.

FIG. 5 is a sectional view of a blower according to a second embodiment of the present invention.

FIG. 6 is a sectional view of a blower according to a third embodiment of the present invention.

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

FIG. 8 is a sectional view of a conventional blower.

[Explanation of symbols]

 Reference Signs List 3 hub part 4 impeller 9, 14, 19 blower 10, 15, 20 guide 11, 16, 21 fan casing 12, 17, 22 air path 13, 18, 24 groove 23 air path member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kenichi Morishita 4-5-2-5 Takaidahondori, Higashi-Osaka-shi, Osaka Inside Matsushita Refrigerating Machinery Co., Ltd. 4-5-2, Matsushita Refrigeration Co., Ltd. F-term (reference) 3H034 AA02 AA18 BB02 BB07 BB08 CC03 DD12 DD28 EE06 EE08

Claims (3)

[Claims] 1. A diameter of a downstream end face of a hub portion of the impeller, which is installed on a downstream side of an axial flow type or mixed flow type impeller, close to the impeller and perpendicular to a rotation axis of the impeller. An air path is formed by a guide whose diameter gradually increases from substantially the same diameter toward the downstream and a discharge surface of a fan casing facing the inclined surface of the guide, and the impeller rotates on the inclined surface of the guide. A blower characterized by having an annular groove centered on a shaft. 2. The groove on the inclined guide surface is a groove that passes through the inside of the guide and returns to the downstream side of the air path between the guide and the discharge surface of the fan casing again. Blower. 3. The blower according to claim 1, wherein the width of the groove on the inclined surface of the guide is partially changed.