JPS60245A - Air straightening device for air curtain - Google Patents

Abstract

PURPOSE:To improve the variability of airstream along the whole length of the blow-off port of the air curtain and uniform the airstream by a method wherein an airstream straightening plate, driving the box of the fan lengthwisely into two parts including the axial line of the axial flow fan, is provided in the device. CONSTITUTION:The variabilities of airstreams at respective points along the whole length of the blow-off port 3 may be improved remarkably by a method wherein the air straightening plate 6, dividing the box 1 of the fan into two parts containing the axial line 5 of the axial fan 4, is provided to blow the airstream off as a curtain stream from the blow-off port 3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an air curtain device using an axial flow as an airflow generation source, and its purpose is to provide a means for forming a homogeneous airflow throughout the air curtain.

Using an axial flow as the airflow generation source of the air curtain has the best energy consumption efficiency with respect to the air volume of the entire air curtain. However, while the direct galvanic current generated by axial flow spreads out in a conical shape, the airflow required for the air curtain is almost flat, so generally the airflow is shown in Figure 3 or Figure 4. Conventionally, in order to transform the shape of the airflow using a gutter-like housing having a funnel-like cross section, and to make the airflow homogeneous in the longitudinal direction of the outlet of the air curtain flow, .72
Based on experience, it was considered optimal to provide a rectifying plate as shown in .

By the way, when the wind speed was actually measured at each point along the length of the air outlet 3 for the airflow generated by the conventional device shown in FIGS. 1 and 3, a characteristic curve as shown in FIG. 5 was obtained. . In other words, the velocity is approximately 10 m/sec or less near the longitudinal center of the outlet 3, while it is 90 m/sec at both longitudinal ends.
% is also large, 19III/sec, and the unevenness is severe in the intermediate part between them. However, the capacity of the axial flow type 4 used in the test is 2.2 KW.

The dimensions (mm) of each part of the device are as shown in the figure, the width of the air outlet 3 is 200 mm, and the measurement points are as shown in FIG. The measured values at measurement points (1) to (24) are shown in Table 1, and the curves in Figure 5 are, for example, (1) and (z), , (3) and (4).
), where the wind speed is high when plotted by the average value of the measured values at measurement points adjacent to the short side of the air outlet 3,
The airflow generated by the axial fan is vortex-like, and this is due to the funder effect, which causes the airflow to flow along the surface of the wall when it hits the wall. Even if the rectifying plates 71 and 72 are installed at the optimum positions based on experience, as shown, the rectifying effect is still very incomplete, and an air curtain with uniform airflow cannot be obtained at all.

In order to further reduce the above-mentioned variations in airflow, either reduce the airflow volume to increase the static pressure inside the housing, or improve the shape and position of the rectifier plate as shown at 71°72 to place it in a location where the airflow is weak. It is conceivable that airflow could be used, but this would not only reduce the meaning of using an axial fan due to the increase in air resistance, but would also cause other drawbacks such as creating a shadow behind the current plate.

By the way, the inventor has found that by providing a rectifying plate 6 that bisects the length of the fourth saliva-holding body 1 in FIG. It was discovered that an air curtain flow close to the ideal can be obtained. That is, this invention:
An intake port 2 is bored in the center of a wide top wall 11 of a gutter-like casing 1 having a short vertical cross section in the shape of a funnel, and a narrow bottom surface is formed as an air outlet 3, which is provided in the intake port 2. In a conventional device in which the airflow generated by the axial fan 4 is blown out from the outlet 3 as an air curtain flow, the airflow is rectified at a position that includes the axis 5 of the axial flow M4 and bisects the length of the housing 1. This is an air curtain rectifier equipped with a plate 6.

FIGS. 2 and 4 show an example of the apparatus according to the invention described above. The dimensions of the housing 1 and the dimensions and capacity of the axial fan 4 are the same as those of the conventional device shown in FIGS. 1 and 3. Each point along the length of the air outlet 3 (the seventh
When the wind speed was actually measured using the air conditioner (see figure), the results shown in Table 2 were obtained. FIG. 6 is a characteristic diagram plotting the average values of each left and right side in Table 2.

The lowest value was 14.3 m7 seconds, while the highest value was 1
7.4 * m7 seconds, the difference is only 20% of the lowest value,
Compared to the conventional device described above, the unevenness of the characteristic line is significantly smaller. In other words, an extremely homogeneous air curtain flow with little variation can be obtained in practice. The average wind speed along the length of the outlet 3 is 15.05 m7 seconds, and the total air volume is 271. It was also found that the wind speed and air volume in m3/min were both higher than those obtained with the conventional device described above. In the illustrated example, the current plate 6 extends to the edge of the outlet 3, but it is not necessarily necessary to do so, and even if it extends far beyond the edge, the characteristics will not be affected much.

Thus, it is clear that according to the present invention, a significantly homogenized air curtain flow can be obtained in an air curtain device using an axial flow station as an air flow generation source. In addition, when attempting to homogenize the airflow by the conventional means shown in FIGS. It is necessary to put it on one side of the hand and leave a space on the other side, which often causes vibrations.In contrast, the rectifying plate 6 in this invention is provided over the entire width of the short side of the housing 1. This is extremely advantageous in terms of construction and reinforcing the casing.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view taken along the length of a conventional air curtain straightening device using an axial fan, FIG. 2 is a longitudinal sectional view similar to FIG. 1 of an air curtain straightening device according to the present invention, and FIG. Fig. 4 is a longitudinal sectional view along the short side of the device shown in Fig. 1, Fig. 5 is a longitudinal sectional view taken along the short side of the device shown in Fig. 2, and Fig. 5 is the wind speed characteristic line of the device shown in Figs. FIG. 6 is a wind speed characteristic diagram of the apparatus shown in FIG. M2 and FIG. 4, and FIG. 7 is a diagram showing measurement points at the outlet. 1 is a housing, 2 is an intake port, 3 is an air outlet, 4 is an axial fan, 5 is an axis, and 6, 71, and 72 are rectifying plates. Patent Applicant Japan Air Curtain Co., Ltd. Representative Patent Attorney Masayoshi Ojo;, l 'lli'・ : ・ $la ２! , 0-

Claims (1)

[Claims] An intake port 2 is bored in the center of a wide top wall 11 of a gutter-like casing 1 having a short vertical cross section in the shape of a funnel, and a narrow bottom surface is formed as an air outlet 3, which is provided in the intake port 2. In the device in which the airflow generated by the axial flow 4 is blown out from the outlet 3 as an air curtain flow, a rectifier plate 6 is provided at a position that includes the axis 5 of the axial flow 4 and bisects the length of the housing 1.
An air curtain rectifier equipped with