JPS62129599A - Cross flow fan - Google Patents

Abstract

PURPOSE:To restrain a drop in air volume by enlarging the length of the wall of a tongue opposite to a wheel and making an eddy current give much the same speed as a flow along the scroll of a casing. CONSTITUTION:A wall 11 opposing a tonque 10 orthogonally intersects an X-axis 50 connecting the apex of said wall 11 to the central point 14 of a cross flow fan 8, and a Y-axis is laid, orthogonally intersecting the X-axis and passing the central point 14. Provided that the outer diameter of a wheel be 'D', a circle having a diameter of 0.15D and a center at (0.1D, -0.15D) and another circle having a diameter of 0.3D and a center at (-0.4D, -0.1D) are drawn respectively, so that a scroll part will be formed on a casing, with a central point set within a region connecting both circles as an end. Consequently, the speed of an eddy current becomes much the same as that of a flow along the scroll, and a drop in air volume can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a cross-flow blower in which an impeller is rotatably housed in a casing.

(b) Prior Art An example of the structure of a cross-flow blower in which an impeller is rotatably housed in a casing is disclosed in Japanese Utility Model Publication No. 58-24099.

According to this content, a guide member having a tongue portion of the impeller is disposed at the front lower part of the impeller, and the back wall of the casing facing the impeller has a smooth spiral curved shape.

By rotating the impeller, a vortex is formed near the tongue, and this vortex guides the air inside the casing from the suction port to the discharge port.

(c) Problems to be solved by the invention In such a cross-flow blower, since the guide member is located at the inferior front part of the impeller, the width dimension of the air passage made up of the guide member and the casing is There was a risk that it would become smaller. As described above, when the width of the air passage becomes smaller, there is a risk that the amount of air discharged will decrease.

An object of the present invention is to suppress a decrease in the amount of air discharged from a cross-flow blower.

(d) Means for solving the problem In order to achieve this object, the present invention arranges the wall surface of the tongue portion to be substantially orthogonal to a line passing through the center point of the impeller, and the length of this wall surface is The dimensions are 10% to 35% of the outer diameter of the impeller.
%, and the horizontal axis is a line passing through the vertex of this tongue and the center point of the impeller, and the vertical axis is a line perpendicular to this horizontal axis and passing through the center point of this impeller. , (0,
A circle with a diameter of 0.15D centered at (1D, -o, 1sp) and a circle with a diameter of 0, centered at (-0,4D, -0,1D).
A scroll portion is formed on the casing of the impeller by drawing a 3D circle and setting the center point within a region connecting both circles as ends.

In addition, the length of the wall surface of the tongue facing the impeller is increased to stabilize the vortex generated by the rotation of the impeller, and this vortex and the flow along the scroll of the casing are approximately the same. −
The speed is set to .

(f) Embodiment FIG. 1 is a longitudinal sectional view of an indoor unit 1 of a separate air conditioner, in which 2 is a main body, and 3 is a front grill that is mounted from the front of this main body. This front grille 3 is provided with a suction port 4 at the top and a discharge port 5 at the bottom.

The main body 2 includes a heat exchanger 6, a drain pan 7 that receives drain water that adheres to the heat exchanger 6 and drips, and a cross-flow fan that exchanges heat between the refrigerant flowing inside the heat exchanger 6 and indoor air. Impeller) 8 has been completely installed. The diameter of this cross flow fan 8 is 90 m. The back surface of the main body 2 has a smooth curved shape (described later) and also serves as a casing 9 of the cross flow fan 8. Drain pan 7
The rear part of the tongue part 10 also serves as a tongue part 10, and the wall of this tongue part 10 is connected to an opposing wall 11 facing the cross flow fan 8 and an outlet wall 1.
It is composed of 2.

The dimensional relationship between the casing 9, the diameter of the cross flow fan 8, and the tongue portion 10 is as described below.

That is, the opposing wall 11 of the tongue portion 10 is 1. An X connecting the apex of this opposing wall 11 and the center point 14 of the cross flow fan 8
It is arranged perpendicularly to the axis 50, and this opposing wall 11
The dimension is 22 mm. 13 is orthogonal to this y-axis,
The y-axis passes through the center point 14 of the crossflow fan.

15 is the center point 17.1 of the scroll portion 16 of the casing
This area 15, where 8 is located, is determined as follows. In other words, with the X-axis 50 and the y-axis 13 as the coordinate axes, draw a circle with a diameter of 13.5111 m (7) centered on point A (9 m, -13,5ff1111), and draw a circle with a diameter of 13.5111 m (7) with point B (-36 mm, -13,5 mm) as the center. Diameter 27 at the center
This is the part that draws a 111m circle and connects the upper and lower parts of the two days with a straight line. 19 is a part of a circular arc having a radius of 52+11111 centered on the center point 17 in the first scroll.

A second scroll 20 is connected to the first scroll 19 and is part of a circular arc with a radius of 72 mm centered on the center point 18. 21 is the straight part and the second scroll 20
is connected to Further, 22 is the angle (
The magnification angle) is set to 17°.

In a cross-flow blower arranged in such a dimensional relationship, when the cross-flow fan 8 is rotated, the air sucked in from the suction port 4 undergoes a heat exchange action in the heat exchanger 6, and then reaches the position indicated by the solid line arrow in FIG. It flows like that. That is, the tongue portion 10
A vortex 25 is formed diagonally above the opposing wall 11 of the . and,
The air 26 flowing along the first scroll 19 and the second scroll 20 spreads approximately concentrically with the center of the vortex 25. In this way, the air flowing along the scroll shows the frequency on the horizontal axis and the noise value on the vertical axis. From this figure, the noise at all frequencies was relatively low and almost unnoticeable. This is believed to be because the speed of the air 26 flowing along the scrolls 19, 20 is slightly lower than or the same as the speed of the vortex 25. still,
The dimension of the wall 11 facing the tongue portion 100 is 22 mm, and this dimension ranges from 10% to 35% of the diameter of the impeller 8.
% is good. Further, if the angle between the opposing wall 11 and the X-axis 50 is approximately 90°±10°, the vortex 25 formed obliquely above the opposing wall 11 of the tongue portion 10 will be stable.

Further, the center of the scroll 19.20 is set to the area 15 mentioned above.
When set to , if the expansion angle 22 is in the range of 5° to 25°, it is considered that air can easily flow along the bulge of the scroll 19, 20.

FIG. 4 shows another embodiment of the cross-flow blower of the present invention, in which the center point 29 of the first scroll 27 and the second scroll 28.
30 is set within the area 15 with an enlarged angle of 6°. It is believed that by rotating the cross flow fan 8, air flows as shown in FIG.
In this case as well, it is thought that the flow 31 along the scrolls 27 and 28 spreads concentrically around the center of the vortex flow 32, similar to the flow of the wind shown in FIG.

Next, five types of cross-flow blowers in which the center of the scroll arc is set outside the area 15 described above will be described. FIG. 6 shows the center point 3 of the scroll 33, 34 above the area 15.
5.36 and the expansion angle is set to 11 degrees. In this case, since there is no bulge in the scrolls 33 and 34, the flow 37 near the scroll becomes faster, and the speed of the vortex 38 increases. It is thought that the speed will also be faster (see Figure 7). As a result, as shown in Figure 8, 715H2 has 3
A high frequency sound of 3.7 dB was generated.

Similarly to FIG. 6, in FIG. 9, the center point 41.42 of the scroll 39.40 is set above the area 15, and the enlargement angle is set to 5°.
In this case, the casing 39
．． Since there is no bulge in 40, the flow near the casing 4
3 is as shown in FIG. 10, and high-frequency sound is expected to be generated.

FIG. 11 shows the center point 4 of the scroll 44 below the area 15.
5 and the expansion angle is set to 30 degrees. In this case, the bulge of the scroll 44 is too large, and as shown in FIG. A vortex 47 is generated, and the scroll 4
The flow velocity of the air 46 in the vicinity of the discharge port 5 decreases, and the amount of air blown out from the discharge port 5 decreases. Also, as shown in Figure 13, 7
A high frequency sound of 28.6 dB at 32 Hz was generated.

14, as well as FIG. 16, the center point 50, 51, 54 of scroll 48, 49, 52, 53 below the area 15.
．． 55 is set, and the enlargement angle is set to 17° and 18°, respectively. In both cases, as shown in Fig. 11, the scroll has a large bulge and there is a vortex 55.55 on the inside of the scroll.
56 (see FIGS. 15 and 17), the amount of air blown out from the outlet 5 is expected to decrease.

In this way, Figure 6, Figure 9, Figure 11, Figure 14, Figure 1
If the center point of the scroll is set outside the area 15 as shown in FIG. 6, the shape of the scroll will not follow the flow of air.

The table below shows the air volume of the blower of the present invention (Figure 1) and the blower used in the experiment (Figures 6 and 11).
With the power of the blower of this invention, a large amount of air was obtained.

(G) Effects of the Invention As described above, the present invention increases the length of the wall surface of the tongue facing the impeller to stabilize the vortex generated by the rotation of the impeller. . Furthermore, since the shape of the blade casing is approximately concentric with the vortex, the speed of the vortex and the speed of the flow along the scroll are approximately the same, making it possible to suppress the noise discharged from the discharge port to a low level.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a heat exchange unit using a cross-flow blower according to an embodiment of the present invention, Fig. 2 is an explanatory diagram showing the air flow inside the unit, and Fig. 3 is a cross-sectional view of a heat exchange unit using a cross-flow blower according to an embodiment of the present invention. A noise characteristic diagram, FIG. 4 is a sectional view of a heat exchange unit using a cross-flow blower according to another embodiment of the present invention, and FIG. 5 is an explanatory diagram showing the air flow inside the blower shown in FIG. 4. 6, 9, 11, 14, and 16 are cross-sectional views of the blower in which the center point of the scroll is set outside the area shown in the present invention, and FIG. 7 and FIG. 10, respectively. , Fig. 12, Fig. 15, Fig. 17
The figures are Fig. 6, Fig. 9, Fig. 11, Fig. 14, and Fig. 16, respectively.
8 and 13 are noise characteristic diagrams when the blower shown in FIGS. 6 and 11 is used. 7...Guide member, 8...Cross flow fan,
9...Casing, 10...Tongue, 15.
...Area, 17.18...Center point, 19.20.
··scroll. Applicant Sanyo Electric Co., Ltd. and 1 other representative Patent attorney Shizuo Sano Figure 1 Figure 3 mK number (H2) Figure 14 Figure 16 Figure 15 Figure 117

Claims (1)

[Claims] (1) In a cross-flow blower in which an impeller is installed inside a casing and a guide member serving as a tongue of the impeller is disposed in front of the impeller, the wall surface of the tongue is a line passing through the center of the impeller. and the length h of this wall surface is 10% to 35% of the outer diameter D of the impeller.
The horizontal axis is a line passing through the vertex of this tongue and the center point of the impeller, and the vertical axis is a line that is perpendicular to the horizontal axis and passes through the center point of the impeller. 1D, -0
．． 15D) with a diameter of 0.15D as the center, (-0
．． 4D, -0.1D) with a diameter of 0.3D as the center, and a scroll is formed on the casing, the center point being within a region connecting both circles as ends. .