JP2001193956A - Indoor unit of air-conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that two-dimensional flow can easily collapse since blade length differs when a load is applied (for example, when dust adheres to a filter for cleaning air) and hence the two-dimensional flow easily collapses near a side wall part for causing an intermittent, abnormal, bustling sound to occur and for causing discomfort. SOLUTION: In an air-conditioner with a once-through fan as the blowing fan of an indoor machine, the maximum thickness position of the blade shape of the once-through fan is set inside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cross-flow fan used in an indoor unit of an air conditioner for cooling or heating a room.

[0002]

2. Description of the Related Art A conventional air conditioner is disclosed in JP-A-9-1007.
As described in Japanese Patent Publication No. 95, the shape is as shown in FIG. The cross-flow fan 1 is divided into a plurality of blocks partitioned by a disk 2 and has a portion where the outer diameter of the blade 3 of at least one block changes between the disks of the block, and is adjacent to the at least one block. The structure is such that the outer diameters of the blades are different at the adjacent portions of the blocks.

A conventional air conditioner is disclosed in Japanese Patent Application Laid-Open No. 10-7798.
As described in Japanese Unexamined Patent Publication No. 8 (KOKAI) No. 8, the shape is as shown in FIG. A pair of disk-shaped or annular end plates 2-1 and 2
, A plurality of blades 3 are arranged in a ring at a predetermined mounting pitch in the circumferential direction and fixed laterally between them, and an end plate 2 is provided at an intermediate portion of the blades 3 in the axial direction.
Is arranged. Both ends in the axial direction of the blade 3 are formed into widened portions Lb and Lc having a long chord length, while the intermediate portion La in the axial direction is integrally connected to a chord width portion La having a short chord length.

The thickness distribution of these blade shapes is classified into the following two types. First, the thickness is constant from the leading edge to the trailing edge. Second, the maximum thickness position is located between the leading edge and the trailing edge.

[0005]

However, in the fan blade of the first conventional example, the length of the blade differs when a load is applied (for example, when dust adheres to the air cleaning filter). Two-dimensional flow easily collapses. Therefore, especially in the vicinity of the side wall, the two-dimensional flow is easily broken, and an intermittent abnormal sound called “unsteady sound” is generated. Further, when a load is applied, the air blowing performance is significantly deteriorated, so that the cooling capacity or the heating capacity is reduced.

The above-mentioned second conventional fan blade also has the same problem. Also, as shown in FIG.
As is apparent from the flow velocity vector of the blow-out portion due to the conventional blade shape, it can be seen that the flow is separated at the leading edge and turbulent flow occurs. The present invention is to solve such a conventional problem, as a way of giving the thickness distribution of the blade shape of the once-through fan, even when a load is applied by setting the maximum thickness position inside the center, A stable flow field can be formed.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to an air conditioner provided with a once-through fan as a blower fan for an indoor unit, and a method of giving a blade-shaped thickness distribution of the once-through fan. , Characterized in that the maximum thickness position is on the inside.

Further, in order to exhibit a remarkable effect, the maximum thickness position of the blade shape of the once-through fan is set at a position of 2% to 35% from the inside of the chord length.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of a cross-flow fan mounted on an indoor unit of an air conditioner and an enlarged view of one blade of the cross-flow fan in the first embodiment of the present invention. The chord length of the blade is represented by a line segment IO. The blade shape is characterized in that the maximum thickness position is disposed inside the center of the line segment.

The maximum thickness position is 2% to 6% from the inside of the chord length.
FIG. 2 shows the result of analyzing the PQ characteristics by changing the position to 0%. The slope at the open point indicates the level of static pressure. FIG. 3 shows the relationship between the inclination and the thickness distribution position. From this, the peak where the static pressure rises is around 4% and 20%
And the static pressure tends to increase as the maximum thickness position moves toward the inner peripheral side. Therefore, it is understood that a high static pressure can be stably obtained at the position where the maximum thickness position is 2% to 35%. FIG. 4 shows the air volume performance per noise. Thus, the maximum thickness position is 2% to 3% from the inside of the chord length.
In the region of 5%, it is almost stable. Here also, it can be seen that the air volume performance per noise is stable when the maximum thickness position is at a position of 2% to 35% inside the center.

Thus, as is apparent from the flow velocity vector of the blow-off portion having the blade shape of the present embodiment shown in FIG. 5, the separation of the flow at the leading edge is reduced, so that a smooth flow is produced and the air volume performance is improved. Could be improved.

[0013]

As is apparent from the above embodiment, since the static pressure is increased, an abnormal noise is less likely to occur even if a load is applied to the air conditioner body. In addition, when the flow condition is analyzed by paying attention to the blowout portion during cooling and heating, the separation of the flow at the leading edge is reduced, and the air volume performance is improved. In addition, since the width gradually increases from the shortest distance between the blades to the blowout portion, trailing edge separation is reduced and the air volume performance is improved.

From the above situation, the turbulence component is reduced and the noise is reduced, and the air volume performance per the same noise is improved. Furthermore, the pressure near the open point will increase, and when it is applied to air conditioners, etc., the heat exchanger will be exposed to dew during cooling, and the dust generated on the filter (buzzing noise) will be generated. Can be suppressed.

Further, when a load is applied, the air blowing performance is significantly deteriorated, so that the cooling capacity or the heating capacity is reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention and an enlarged view of one blade.

FIG. 2 is a graph showing PQ characteristics.

FIG. 3 is a diagram showing the relationship between the level of static pressure and the thickness distribution position.

FIG. 4 is a diagram showing air volume performance per noise;

FIG. 5 is a flow velocity vector diagram of a blade blowing portion according to one embodiment of the present invention.

FIG. 6 is a front view of a conventional once-through fan.

FIG. 7 is a front view of a conventional once-through fan.

FIG. 8 is a flow velocity vector diagram of a conventional blade blowing section.

[Explanation of symbols]

 1 once-through fan 2 disk 3 blade

Continued on the front page (72) Inventor Shigeru Nari 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. Reference) 3H031 AA03 BA02 3H033 AA02 AA18 BB02 BB09 DD03 EE06 EE08 3H035 CC01 CC06 3L049 BB07 BD02

Claims (2)

[Claims] 1. An air conditioner having a cross-flow fan as a blower fan for an indoor unit, wherein the blade shape of the cross-flow fan is such that a maximum thickness position is located inside (inner diameter side) from a center. Indoor unit of the machine. 2. The cross-flow fan for an indoor unit of an air conditioner, wherein the maximum thickness position of the blade shape of the cross-flow fan is 2% to 35% from the inside of the chord length.