JPS5938497B2 - Air volume control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air volume control device for an air conditioning supply/exhaust system, and more particularly to a suitable air volume control device that prevents noise generated during air volume control.

As shown in FIG. 1, the air volume control device in a conventional air conditioning air supply/exhaust system includes two blades 2A, 2 inside a casing 1 that rotate in opposite directions in conjunction with each other around rotating shafts 3A, 3B.
B, or a parallel airfoil damper with two parallel blades 2C and 2D that rotate in the same direction around rotational axes 3C and 3D in the casing 1 as shown in Fig. 2. Either a damper or a single-blade damper (not shown) is used, which has a single blade inside the casing and controls the air volume by rotating the blade around a central rotating shaft.

These air volume control devices are provided in the middle or at the end of the air conditioning duct system.

The air volume is controlled by rotating the blades 2A and 2B of the opposed airfoil damper shown in FIG. This is done by rotating the blades 2C and 2D to control the flow path area.

However, in such a conventional air volume control device, since the blades 2A, 2B, 2C, and 2D are flat, drifting and separation occur in the air flow when the blades 2A, 2B, 2C, and 2D open and close. These have the drawback of being easy to induce and generate swirling noise.

The object of the present invention occurs during air volume control.

An object of the present invention is to provide an air volume control device that can reduce noise.

The present invention has confirmed through basic experiments regarding airflow noise that airflow and noise can be reduced by colliding and merging two flows, breaking the ejected part, and creating a Kashihara state. It is divided into two passages, a single-blade damper is installed in each passage, and each deck is rotated in opposite directions to control the air volume, making the two flows contradictory.
The idea is to reduce the generation of airflow noise by merging them together.

Examples of the present invention will be described below.

FIG. 3 shows a perspective view of an air volume control device showing one embodiment of the present invention.

In the figure, a casing 10 serving as an airflow passage is provided with a partition plate 13 approximately at the center with respect to the airflow direction X so that the cross-sectional shapes of the two passages 11 and 12 are the same.

In these two passages 11° 12, a rotating shaft 14B is provided perpendicularly to the partition plate 13.

A single blade damper 14, 15 is provided so as to be rotatable by the damper 15B.

This one-blade damper 14 has a blade 14A having the same width as the passage 110 and a length long enough to close the passage 11 when it is fully closed, and a blade 14A for rotating the blade 14A. It consists of a rotating shaft 14B.

Similarly, the single blade damper 15 has a blade 15A and a rotary shaft 1.
It consists of 5B.

Flanges 16 are provided at both ends of the casing 1.

The two single-bladed dampers 14 and 15 are configured to rotate in opposite directions.

That is, the single-blade damper is rotated in the opposite direction as the damper changes from fully open to closed.

The opening degree of this pair of blades (two blades next to each other) is the same, but the direction of the gas flowing out is diagonally downward and toward the soil, so they interfere with each other. to eliminate the noise generated.

As a method of making the blades rotate in the opposite direction, there is a method of installing a bevel gear between the rotating shafts of the blades to reverse the direction of transmission of the blade angle, or as shown in FIG.
The rotating shaft 15B of A is doubled, and each rotating shaft 14B, 1
This can also be done by turning 5B in the R1S direction.

In this way, the directions of the vortices generated after passing through the openings of adjacent dampers 14.15 are opposite,
The rotation direction of the dampers 14 and 15 is opposite, and they are configured to rotate in conjunction with each other so as to maintain the same opening degree, and the air volume that generates the vortex is the same, so the air after passing through the dampers 14 and 15 is When the vortexes merge, the vortexes in different directions collide with each other, dividing the vortex flow into small pieces, thereby suppressing the generation of noise.

Figure 5 shows the noise generated during air volume control using the present embodiment and the conventional single-blade damper (wind speed -9m/s diameter 3oox3o).
Comparative experimental results for o) are shown.

According to this embodiment, when the opening degree θ of the damper is θ=45°, the result B of this embodiment is much lower than the conventional example A, and θ=2
Even at 2.5°, the results of this example are significantly lower than those of conventional example C.

That is, there is a noise reduction effect of 5 to 10 dB regardless of the opening degree of the blades.

Further, according to this embodiment, even in pressure loss, which generally increases when noise countermeasures are taken, there is almost no difference between the embodiment B and the conventional example A, as shown in FIG.

In the above embodiments, the air volume control device was divided into two passages, but it may have multiple passages, such as three passages or four passages.

Further, in the above embodiment, the blades 14A and 15A are formed into plate shapes, but if they are formed of perforated plates and filled with a sound absorbing material inside, the sound absorption effect will have a sound silencing effect when controlling the air volume. increases.

As described above, according to the present invention, it is possible to reduce noise generated during air volume control.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an air volume control device using a conventional opposed vane damper, FIG. 2 is a sectional view of a conventional air volume control device using a parallel vane damper, and FIG. 3 is a sectional view of an air volume control device using a conventional parallel vane damper. FIG. 4 is a perspective view of the blade of the embodiment shown in FIG.
FIG. 5 is a diagram showing measurement results of noise generated in the embodiment shown in FIG. 3 and the conventional example, and FIG. 6 is a diagram showing pressure loss characteristics of the embodiment shown in FIG. 3 with respect to the conventional example. 10...Casing, 11.12...Passage, 13.
...Block plate, 14.15...Single blade damper, 14
A. 15A...Blade, 14B, 15B... Rotating shaft, 16
...flange, 17...bulkhead.

Claims (1)

[Scope of Claims] 1. The inside of an air conditioning duct is divided into two or more passages in the direction of airflow, and each passage is equipped with a single blade-shaped damper with each rotating shaft substantially perpendicular to the direction of airflow. Place it so that it is on the line,
The single-blade dampers installed in each channel alternately operate in opposite directions and rotate while maintaining the same opening to adjust the opening, thereby changing the flow area of the air conditioning duct and providing air conditioning. An air volume control device characterized by controlling the air volume in a duct and merging the controlled air flows in each passage. 2. The air volume control device according to claim 1, wherein the passage is on a side that is a multiple of 2. 3. The air volume control device according to claim 1 or 2, wherein the two or more passages are arranged in parallel in the flow direction of the air conditioning duct. 4. The air volume control device according to any one of claims 1 to 3, wherein the single-blade damper is constructed of a perforated plate. 5. The air volume control device according to claim 4, wherein a sound absorbing member is filled inside the single-bladed damper made of the perforated plate.