JPH0650287A - Blower - Google Patents

Abstract

PURPOSE:To reduce blowing noise due to turbulence and to improve blowing performance by tilting the outer peripheral part of a blade backward in the anti-rotating direction on the same height, whereby an air flow on the suction surface side in the outer peripheral part of the blade is restrained and prevented from colliding with an air flow on the pressure surface side. CONSTITUTION:A blower 1 comprises an impeller 3 formed by arranging plural blades 8 in the circumference of a hub 4 fitted to a motor 2. The outer peripheral part 8b on the discharge side of each blade 8 is enveloped in an orifice 6. In this case, the outer peripheral part 8b of each blade 8 is tilted backward in the anti-rotating direction on the same height. An air flow W1 having high flow velocity W1, which is blown off from the vicinity of the suction surface side 8b2 to the outer periphery in the outer peripheral part 8b is restrained, whereby the air flow W1 is prevented from colliding with an air flow W2 which wraps round the suction surface side 8b2 from the vicinity of the pressure surface side 8b1, and it is possible to avoid an air flow from being turbulent in the outer periphery of the blade 8 not enveloped in the orifice 6. Thus, it is possible to accomplish lowering of blowing noise and improvement in blowing performance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blower used in an air conditioner or the like.

[0002]

2. Description of the Related Art In recent years, blowers such as axial blowers have been widely used as blowers for separate type air conditioners from commercial use to household use, and are being used for downsizing of equipment and diversification of equipment installation conditions. Accordingly, there is a tendency for higher performance and lower noise.

The conventional blower described above will be described below with reference to the drawings. 5 to 8 show the structure of a conventional blower. In the figure, 1 is a mixed flow blower, 2 is a motor, 3 is an impeller consisting of a hub 4 attached to the motor 2 and a plurality of blades 5 provided around the hub 4, Reference numeral 6 denotes an orifice that surrounds the outer periphery of the discharge side 5c of the blade 5. Reference numeral 7 denotes a panel for deflecting the airflow discharged in a substantially axial direction from the blades 5 arranged on the discharge side of the impeller 3 in a substantially radial direction.

The operation of the blower configured as above will be described below. First, the impeller 3 is driven by the motor 2.
When is rotated in a predetermined rotation direction, air flows into the impeller 3, is subjected to static pressure and dynamic pressure by the action of the vanes 5 and is discharged to the outside of the impeller 3, and is substantially axially moved by the panel 7. The discharged airflow is deflected in a substantially radial direction and blown out of the blower 1 to perform a blowing operation.

[0005]

However, in the above-mentioned configuration, as shown in FIG. 8 based on the airflow vector inside the impeller and the measurement result of the velocity fluctuation in FIG. 9, the impeller 3 is used.
Since the panel 7 is installed on the discharge side of the impeller 3 to deflect the air flow discharged from the impeller 3 from the substantially axial direction to the substantially radial direction, a high static pressure condition is set for the blower 1 and the suction side 5a of the blade 5 of the impeller 3 is provided. Since the air velocity flowing in from the air flow velocity component decreases in the axial direction and increases in the radial velocity component, the air flow is inclined toward the outer peripheral side, and a part of the air flow is in the vicinity of the pressure surface side 5b1 of the outer peripheral portion 5b of the blade 5 and the negative pressure surface side. 5b2 near the outer periphery of the blade 5 is not surrounded by the orifice 6,
It causes a flow to be sucked from the center between the blades of the impeller 3.

In particular, since the pressure distribution between the blades of the impeller 3 is high on the pressure surface side and low on the suction surface side, the velocity of the air flow is very high, and the outer peripheral portion 5b of the blade 5 is moved from the vicinity of the suction surface side 5b2 to the outer periphery. The air flow W1 that blows out to the pressure surface side 5b of the outer peripheral portion 5b
When a collision occurs with the airflow W2 that circulates from the vicinity of 1 to the outer circumference on the suction surface side 5b2 of the outer peripheral portion 5b, it causes a large turbulence and is sucked from the center between the blades of the impeller 3 and the blade 5 The flow is greatly disturbed at the outer peripheral portion 5b. Therefore, there is a problem that the blowing performance of the impeller 3 deteriorates and the turbulent sound generated increases.

In view of the above problems, the present invention provides a blower having a panel for deflecting the air flow discharged to the discharge side of an impeller from a substantially axial direction to a substantially radial direction under a high static pressure condition. Part of the airflow that flows in from the suction side of the impeller, when used in the
It is intended to provide a blower that prevents blown air to the outer periphery of an impeller that is not surrounded by an orifice and that prevents the flow from being sucked from the center of the blades of the impeller, and that suppresses an increase in blast noise as well as deterioration of blast performance.

[0008]

In order to solve this problem, the blower of the present invention comprises a motor, a hub attached to the motor, and a plurality of blades provided around the hub. And an orifice surrounding the discharge side outer periphery of the blade, and the outer peripheral portion of the blade is tilted backward in the counter-rotational direction at the same height.

[0009]

With this configuration, the blower having a panel for deflecting the air flow discharged to the discharge side of the impeller from the substantially axial flow direction to the substantially radial direction is used under high static pressure conditions. In this case, the flow of the strong airflow of the radial component on the suction surface side of the blade outer peripheral portion is suppressed, and the airflow of a high velocity flowing out from the vicinity of the suction surface side of the outer peripheral portion of the blade to the outer periphery is suppressed,
Prevents collision with the air flow that circulates from near the pressure surface side to near the suction surface side, and allows the air flow to smoothly flow in from the outer circumference.
It also suppresses turbulence in the flow on the outer peripheral side.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In addition, in order to avoid duplication, the same components as those of the conventional example will be denoted by the same reference numerals and description thereof will be omitted.

1 to 3 show the structure of a blower according to an embodiment of the present invention. In the figure, 8 is a hub 4.
A plurality of blades are provided around the periphery of the blade, and the outer peripheral portion 8b of the blade 8 is tilted backward in the counter-rotational direction at the same height as shown in FIG.

The operation of the impeller of the blower configured as above will be described below. First, when the impeller 3 is rotated by the motor 2 in a predetermined rotation direction, air flows into the impeller 3, and static pressure and dynamic pressure are added by the action of the blade 8 to be discharged to the outside of the impeller 3. The panel 7 deflects the air flow discharged in the substantially axial direction in the substantially radial direction and blows the air out of the blower 1.

As shown in FIG. 4, in the outer peripheral portion 8b of the blade 8 which is inclined rearward, the strong radial airflow in the vicinity of the suction surface 8b2 is suppressed, and the negative inclination of the rear inclined outer portion 8b is suppressed. The airflow W1 having a high flow velocity blown out from the vicinity of the pressure surface side 8b2 to the outer periphery is suppressed, and it is prevented from colliding with the airflow W2 flowing from the vicinity of the pressure surface side 8b1 to the vicinity of the suction surface side 8b2, and is not surrounded by the orifice 6 of the blade 8. Outer peripheral portion 8b
It is possible to prevent the flow from being greatly disturbed in the outer circumference in the vicinity of the negative pressure surface side 8b2, to smoothly allow the airflow sucked from the outer circumference to the center between the blades, and to suppress the flow disturbance on the outer circumference side.

As described above, according to the present embodiment, by tilting the outer peripheral portion 8b of the blade 8 backward in the counter-rotational direction on the same height, the flow velocity blown to the outer peripheral portion from the vicinity of the suction surface 8b2 of the outer peripheral portion 8b. The airflow W1 is suppressed to prevent the airflow W1 from colliding with the airflow W2 flowing from the vicinity of the pressure surface side 8b1 to the vicinity of the suction surface side 8b2, and the vicinity of the negative pressure surface side 8b2 of the outer peripheral portion 8b not surrounded by the orifice 6 of the blade 8. The flow is prevented from being greatly disturbed on the outer periphery of the blade, the flow is smoothly made from the outer periphery to the center of the blade, and the flow disturbance on the outer peripheral side is suppressed.

Therefore, it is possible to suppress an increase in blast noise due to turbulence of the flow in the outer peripheral portion 8b of the blade 8 and to suppress deterioration of the blast performance of the blower 1.

In this embodiment, the oblique flow type blower has been described as an example, but the same effect can be obtained with an axial flow type blower.

[0017]

As described above, the blower of the present invention includes the motor, the hub attached to the motor, the impeller including the plurality of blades provided around the hub, and the blade. It is composed of an orifice that surrounds the outer circumference of the discharge side,
By tilting the outer peripheral portion of the blade rearward in the counter-rotational direction at the same height, the flow of a strong radial component air flow on the blade outer peripheral negative pressure surface side is suppressed, and the blade outer peripheral portion near the negative pressure surface side. Suppresses the high-velocity airflow that blows out from the outer circumference to prevent collision with the airflow that wraps around from the pressure surface side to near the suction surface side, allows the airflow to smoothly flow in from the outer circumference, and suppresses turbulence on the outer circumference side. . Therefore, while suppressing the increase of blast noise due to the turbulence of the flow in the outer peripheral portion of the blade,
It is possible to suppress deterioration of the blowing performance of the blower.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a mixed flow blower according to an embodiment of the present invention.

FIG. 2 is a plan view of a mixed flow blower according to an embodiment of the present invention.

FIG. 3 is a side view of a main part of the blower shown in FIG. 1 viewed from a direction of an arrow (lateral direction).

FIG. 4 is an enlarged view of a main part showing a state of air flow of a mixed flow type blower in one embodiment of the present invention.

FIG. 5 is a sectional view of a conventional mixed-flow blower.

FIG. 6 is a plan view of a conventional mixed-flow blower.

FIG. 7 is a side view of a main part of the blower shown in FIG. 5, viewed from the direction of the arrow (lateral direction).

FIG. 8 is an enlarged view of a main part showing a state of air flow of a conventional mixed-flow blower.

FIG. 9 is an enlarged view of a main part showing an air flow vector inside the impeller of a conventional mixed-flow blower and a measurement result of speed fluctuation.

[Explanation of symbols]

 1 Blower 2 Motor 3 Impeller 4 Hub 6 Orifice 8 Blade 8b Outer peripheral part

Claims (1)

[Claims] 1. An impeller comprising a motor, a hub attached to the motor, a plurality of blades provided around the hub, and an orifice surrounding an outer periphery of the blade on the discharge side. A blower in which the outer peripheral portions of the blades are tilted backward in the counter-rotational direction on the same height.