JPH048711B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an airflow circulation method for an open show case in which at least two or more layers of air curtains are formed in openings for storing and taking out products. The purpose is to prevent

Generally, as shown in FIG. 1, this type of open case main body 1 has an opening 4 for storing and taking out products on one side, for example, the front, of an inner box defining a storage chamber 2, and a plurality of sheets surrounding the inner box 3. A plurality of passages 7, 8 are provided by discharging the partition walls 5, 6, and air outlets 9, 11 and suction ports 10 of the passages are provided on both sides of the opening.
12, a cooler 13 in the inner passage 7, a blower 14 that divides the passage 7 into two and divides the circulating air flow into a high-pressure side and a low-pressure side, and an outer passage 8 with a cooler 13, and a blower 14 in the outer passage 8.
A blower 15 is installed which divides the circulating air into two parts, a high pressure side and a low pressure side.

By operating the cooler 13 and the blower 14, a high-velocity cooling air flow indicated by a solid line is circulated through the inner passage 7, and a low-velocity protective air flow indicated by a dashed line is circulated through the outer passage 8. Low temperature air curtain 16, protective air curtain 17 on the outside
This is to cool the storage chamber 2 by forming an air pocket, and to protect the air mass of the storage chamber 2 from the outside air.

The cooling and protective air flows forming the air curtains cannot maintain the initial velocity at the air outlets 9 and 11 due to air resistance while passing through the opening 4, and as they flow down, the cold air from the storage chamber 2 is dissipated in the inner part. Since the air mass and the outside part are expanded by drawing in still air, the majority of the cooling air flow includes the cold air mass and a part of the protection air flow, and the majority of the protection air flow includes the cooling air flow and a part of the outside air. However, the diffused part of the protective air overflows from the opening 4 and stays on the floor at the front of the main unit, creating a cooling sensation on the customer's feet. It will be a cold yell to give.

That is, although the volume of each cold air flow blown out from both the air outlets 9 and 11 and the intake volume of each air flow sucked in from the suction ports 10 and 12 are equal because they circulate through the same passages 7 and 8, The suction air volume of the suction port 12 is smaller than that of the suction port 10, and the air curtain is sucked into each passage 7, 8 sequentially from the inside of the storage room, which is a closed space, and is diffused to the outside of the storage room, which is an open space. Since the outside air near the suction port 12 is taken in instead of a part of the airflow to supplement the suction air volume, there is a drawback that cold air occurs and the refrigeration load increases.

Among the above drawbacks, as a means to prevent overflow,
A method has been adopted in which a through hole 18 is formed in the partition wall 6 and a portion of the protective airflow is discharged to the outside to reduce the amount of air blown out. Although this method can certainly reduce overflow, On the contrary, there was a drawback that the amount of outside air sucked in from the suction port 12 increased, and the refrigeration load further increased.

The present invention has been made in view of these drawbacks.
The embodiment will be explained below with reference to FIGS. 2 and 3. In addition, in FIGS. 2 and 3, the same reference numerals as in FIG. 1 indicate the same parts.

19 shown in FIG. 2 represents the inner passage 7 and the outer passage 8.
The outlet side of the partition wall 5 that partitions the two passages 7,
A blower 14, which divides both the passages 7 and 8 into two and divides the circulating air flow into a high-pressure side and a low-pressure side, with a flow path formed in a portion located on the windward side of each blower 14, 15 of 8.
It is located on the high pressure side when viewed from 15, and communicates both passages 7 and 8. Reference numeral 20 shown in FIG. 3 is a guide plate disposed on the inner passage 7 side of the flow path 19, which functions as a resistance plate and an ejector device for reducing the passage of air flow in the flow path 19.

That is, as shown in FIG.
Before forming the air curtain 17, which has a lower speed than the air curtain 17 (naturally, the air curtain 16 is higher than the air curtain 17 in terms of air pressure), a part of the protective airflow in the passage is used to form the air curtain 16, which has a faster speed. A flow path forcibly introduced into the inner passage 7 from which the cooling air flow is blown out, in other words, the speed of the cooling air flow passing through the inner passage 7 is faster than the protective air flow, and the opening area is made smaller by the guide plate 20. Even with the ejector effect using the flow path 19, a part of the protective airflow can be forcibly introduced into the inner passage 7, and the blowing air volume of the inner passage 7 can be increased compared to the state without the flow passage 19. By setting the air volume of the air flow smaller than that without the flow path 19 and maintaining the sum of the air volumes of both air flows the same as compared to the state without the flow path 19, the circulation of the entire open show case 1 is improved. While the blowing speed of the inner passage 7 can be increased without changing the amount of air, the blowing speed of the outer passage 8 can be slowed down.
In the turbulent region where the initial velocity cannot be maintained due to the decrease in the air velocity, the air curtain 17 is gradually attracted by the fast-moving air curtain 16, so the diffusion width of the air curtain 17 is small, that is, the air curtain 1
7 is reduced, and overflow of the protective airflow from the opening 4 can be prevented.

According to the present invention described above, a slow air flow is allowed to pass through the outermost passage, while a fast air flow is passed through the inner passage adjacent to the outermost passage, and both the passages are partitioned. A flow path is formed in the partition wall that connects both passages on the high pressure side, and a portion of the air flow from the outermost passage is forcibly introduced into the inner passage, reducing the airflow volume from the inner passage to the state where there is no flow passage. The output air volume of the outermost passage is set to be smaller than when there is no flow passage, and the sum of the suction air volumes of both air flows is maintained at the same level compared to when there is no flow passage. Since the amount of air blown from the outside passage can be increased, the airflow speed from the inside passage can be increased without changing the amount of circulating air in the entire open case.
The protective airflow that can slow down the blowout speed of the outer passage and thus forms an air curtain in contact with still air, has a lower flow rate at the opening, and in the turbulent area where the initial velocity cannot be maintained, the protective airflow gradually changes to the faster air curtain. Because it will be attracted to
The diffusion width of the air curtain is small, that is, the turbulence of the air curtain is reduced, and overflow of the protective airflow from the opening can be prevented. As a result, the refrigeration load on the opening can be reduced.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of a conventional open-shoulder case, FIG. 2 is a vertical cross-sectional view of the open-shallow case of the present invention, and FIG. 3 is an enlarged view of the same essential parts. 5... Partition wall, 7, 8... Passage, 9, 11...
Air outlet, 10, 12... Suction port, 16, 17...
Air curtain, 19... flow path.

Claims (1)

[Claims] 1. A storage room with an opening for storing and taking out products on one side, and a blower surrounding each storage room. and a plurality of passages with the windward side being the low pressure side of the circulating air, and each air flow that has passed through each passage is blown out to the opening to form a multilayer air curtain including a low temperature air curtain in the innermost layer. In an open show case, the outermost passage allows a slow air flow to pass through, while the inner passage adjacent to the outermost passage allows a fast air flow to pass through, and a partition partitions the two passages. A flow path is formed in the wall that connects both passages on the high-pressure side, and a part of the airflow from the outermost passage is forcibly introduced into the inner passage, thereby increasing the suction air volume of the inner passage. The open air case is configured such that the intake air volume of the outermost passage is set to be larger than that of the state in which there is no flow path, and the suction air volume of the outermost passage is set to be smaller than that of the state where there is no flow path, thereby maintaining the sum of the outlet air volume of both air flows at a constant value. airflow circulation method.