JPS6014988B2 - open case - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an open air vent that has an improved forced circulation cold air air curtain that closes the opening.

As shown in Fig. 1, the main body of a general open showcase is composed of a heat insulating wall 2 that forms a closed opening 3 at the front, and a partition plate 4 is disposed at an appropriate distance from the inner wall of the heat insulating wall for cooling. A cold air passage 5 and multiple shelves 9 in which a container 7 and a blower 8 are installed.
. The closed opening 3 is closed and the storage chamber 6 is cooled by an air curtain of a forced circulation cold air flow formed by the operation of the storage chamber 6.

Since the cold air flow blown out from the outlet 12 to the closing port 3 is a flowing gas having a constant speed, it entrains the indoor cold air and the outside air, which are stationary gases, by its entrainment action.

The entrainment effect is large near the outlet 12 where the velocity is farthest, and becomes smaller toward the downstream. Size of entrainment action, air outlet 1
The cold air flow near 2 draws in the cold air in the storage chamber 6 with its inner flow, so that the pressure in the upper storage space near the outlet 12 is lowered than the outside pressure. For this reason, the cold airflow blown out from the outlet 12 is curved toward the indoor side at the upper part of the exit 3, and this curved cold airflow hits the tip of the top shelf 9 and becomes turbulent, increasing the amount of outside air entering and reducing the refrigerating capacity. Undesirable problems such as an increase in indoor temperature and an increase in frost formation on the cooler 7 have occurred. In addition, Fig. 2 shows a structure in which a hole 14 is provided in the ceiling wall 4a of the partition plate 4 and cold air is blown out along the ceiling wall 4a, but this simply raises the temperature of the ceiling wall 4a to be higher than the fog point temperature of the cool air in the room. This prevents fog from forming on the ceiling wall 4a, but does not eliminate the curvature of the cold air flow.

In addition, FIG. 3 shows a structure in which a large number of holes 15 are provided in the back wall 4b of the partition plate 4 to blow out cold air toward the cold air flow that closes the closing opening 3. Since the flow rate and velocity from the hole 15 are inversely proportional,
If the flow rate from the outlet 12 is increased, the flow rate from the hole 16 will decrease, making it impossible to eliminate the curvature, and if the flow rate from the hole 15 is increased, the flow rate from the outlet 12 will decrease, making it possible to cool the opening ○3. If the product cannot be blocked by the airflow and the product is stored, there is a risk that the product will block the hole 15, and in any case, it is difficult to form a normal air curtain at the entrance 3 with the cold airflow blown out from the outlet 12. It was a problem.

In addition, as seen in the refrigerating container of Japanese Patent Publication No. 46-3044, a multilayer air curtain is formed in close contact with each other at the entrance, and the innermost layer of the air curtain is used as a cold air flow. The thickness of the air curtain becomes thicker in the storage room, and the amount of outside air entering the storage room through the openings can be reduced, but since the air curtains are in close contact with each other, the air curtains are substantially thicker than those shown in Figure 1 above. As explained above, the upper storage space becomes negative pressure, and the air curtain flows in a curved manner toward the inside of the storage chamber and hits the tip of the uppermost shelf, resulting in the problem of turbulent flow in the air curtain.

The present invention has been made in view of the above-mentioned problems, and embodiments thereof will be described below with reference to FIGS. 4 to 6.

Note that the same numbers are given to parts corresponding to those of the conventional example. In FIG. 4, reference numeral 16 designates at least one row of blow-off holes formed in the top wall 4a of the partition plate 4 at the rear, which is located near the blow-off port 12 and slightly away from the blow-off port, as shown in FIGS.
It is provided in parallel along the uppermost shelf 9 and is located above the tip of the uppermost shelf 9, and blows out a part of the cold air flow from the cold air passage 5 to the outlet 12 toward the tip of the shelf 9.

Reference numeral 17 denotes a small low-pressure region formed between the cold air flows blown out from the blow-off port 12 and the blow-off hole 16, and the volume between the inner flow of the cold air flow from the blow-off port 12 and the outer flow of the cold air flow from the blow-off hole 16. Formed by embedding action.

This low-pressure region is spaced behind the cold airflow that is blown out from the outlet 12 and forms an air curtain, and the cold airflow from the outlet 16 is directed toward the tip of the shelf 9, and these two cold airflows are merged above the tip of the shelf 9. As a result, it is formed as a result. According to this configuration, the cold air flow that is blown out from the blow-off hole 16 located slightly behind the blow-off port 12 toward the tip of the uppermost shelf 9 and that is separated from the cold air flow that forms an air curtain is directed to the cold air passage 5. It is a part of the cold air flow that passes through the air outlet 12 and reaches the air outlet 12, and forms an air curtain in order to weaken the speed of the cold air flow that is blown out from the air outlet 12 and to reduce the flow rate. It is possible to reduce the pressure drop in the upper storage space of the storage chamber 6 by weakening the entrainment effect of the cold air flow, and on the other hand, the inner flow of the cold air flow blown out from the blow-off hole 16 circulates in the upper storage space and In order to increase the pressure in the space, the pressure drop in the upper storage space due to the entrainment effect of the air curtain can be offset by this pressure increase, and the inner flow of the cold air flow from the outlet 12 By separating the outer flow of cold air from the outlet 16 and then merging it above the tip of the uppermost shelf 9, the entrainment effect of the inner flow of the cool air from the outlet 12 is reduced. By compensating with the outer flow of cold air from the air curtain, it is possible to prevent the air curtain from curving upstream toward the upper storage space.
Moreover, since the blow-off hole 16 is located slightly behind the blow-off hole 12, the cold air flow from this blow-off hole flows away from the air curtain until it reaches the core region where its initial blowing velocity can be maintained, and then passes through the core region. The outer flow merges with the inner flow of the air curtain above the tip of the uppermost shelf 9, and as a result, a low pressure region 17 is formed in the area above the merged portion, and air is emitted from the blowout hole 16. It is possible to prevent the cold air flow from coming into close contact with the air curtain immediately after it is blown out, and it is possible to avoid a pressure drop in the upper storage space due to the close contact between the two.

As described above, the present invention consists of a main body composed of a heat insulating wall that forms a gate on the front, and partition plates are arranged at appropriate intervals from the heat insulating wall to form a cold air passageway in which a cooler and a blower are installed, and a shelf. In an open showcase formed by forming a storage room with a storage room, an air outlet at the upper end of the entrance, an air outlet at the lower end, and closing the openings with an air curtain of forced circulation cold air, A few rows of blow-off holes parallel to the blow-off holes are formed in the rear partition plate wall above the top of the upper shelf and slightly away from the blow-off holes, and air is blown from these blow-off holes toward the top of the top shelf. The inner flow of the cool air flow blown out from the outlet is circulated to the upper storage space, and the inner flow of the cool air flow blown out from the outlet and the outer flow of the cool air flow blown out from the outlet are circulated above the tip of the uppermost shelf. Since it is characterized by merging, as the cold air flow is blown out from the outlet, the speed of the cold air flow from the outlet is weakened and the flow rate is reduced, thereby reducing the entrainment effect of the air curtain. While reducing the pressure drop in the upper storage space by weakening the top, the inner flow of cold air from the outlet can increase the pressure in the upper storage space and offset the pressure drop. The entrainment effect of the inner flow is compensated by the outer flow of cold air from the outlet,
Moreover, this separation relationship between the inside and outside airflows prevents them from coming into close contact with each other, and the upstream side of the air curtain hits the tip of the top shelf due to the curvature, avoiding turbulent airflow and creating a laminar flow of air when the opening is closed. It can form a curtain and contribute to reducing the refrigeration load when the door is closed.

[Brief explanation of the drawing]

Figure 1 is a vertical sectional view of the open showcase of the subordinate structure, Figure 2
3 and 3 are longitudinal cross-sectional views of main parts of a conventional open showcase, FIG. 4 is a longitudinal cross-sectional view of main parts of an open showcase of the present invention, and FIG. 5 is a cross-sectional view taken along the line A-B in FIG. 4. , 6th
The figure is an enlarged perspective view of the figure. 3...Open □, 4...Division board, 4a...
...Husband wall, 5...Cold air pilgrimage, 6...Storage room, 9...Shelf, 12...Air outlet, 16...
...Blowout hole. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1 The main body is composed of a heat insulating wall with an opening in the front, a cold air passageway in which a cooler and a blower are installed by arranging partition plates at an appropriate distance from the heat insulating wall, and a storage room having shelves. In an open case in which an air outlet is formed at the upper end of the opening, an inlet is formed at the lower end of the opening, and the opening is closed with an air curtain of forced circulation cold air, the uppermost shelf of the shelves is At least one row of blow-off holes parallel to the blow-off holes is formed in the top wall of the rear partition plate above the tip and slightly away from the blow-off holes, and the cool air is blown out from the blow-off holes toward the tip of the uppermost shelf. The inner flow of cold air blown out from the outlet is circulated to the upper storage space, and the inner flow of cold air blown out from the outlet and the outer flow of cold air blown out from the outlet are combined above the tip of the uppermost shelf. An open case.