JP3157360B2 - Cooler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called plate-fin type cooler disposed in a cool air duct such as a low-temperature showcase.

[0002]

2. Description of the Related Art Conventionally, in a low-temperature showcase,
For example, JP-A-63-58082 (F25D21 /
As shown in 06), a cooler is installed vertically behind the cold air duct formed in the heat insulating wall, and a reduced-pressure refrigerant is supplied to the cooler to evaporate it, thereby exerting a cooling effect, and the cooler is provided with a cooler. The air was circulated from bottom to top by a blower to exchange heat, and then discharged from a discharge port to cool the storage room.

FIG. 3 is a side view of a conventional cooler 100 provided in the low-temperature showcase shown in FIG. Cooler 100
Is a plurality of heat exchange fins 1 made of an aluminum thin plate.
And a refrigerant pipe 101 penetrating the heat exchange fins 105 and arranged in a meandering manner. The refrigerant pipes 101 are provided in two rows between an inlet pipe 102 formed of a branch pipe located at one end of the cooler 100 and an outlet pipe 103 formed of the same branch pipe located at the other end of the cooler 100. Each row is arranged in a meandering manner at intervals from each other.

[0004] When the air flowing through the duct flows from bottom to top as indicated by the arrow in FIG.
00 is installed in the vertical direction. At this time, the inlet pipe 10
Reference numeral 2 denotes an upper end of the cooler 100, that is, a downstream side of the circulation air, and the cooler 100 is disposed in a duct (not shown) such that the outlet pipe 103 is a lower end of the cooler 100, that is, an upstream side of the circulation air. .

[0005]

SUMMARY OF THE INVENTION A cooler 10 having such a configuration is described.
The high-temperature and high-pressure refrigerant discharged from a compressor (not shown) is also condensed in a condenser (not shown) in the refrigerant pipe 101 of the first refrigerant line, and is decompressed by a pressure reducing device (not shown). Then, they are separated and evaporated while flowing down each row, exhibiting a cooling effect and flowing out from the outlet pipe 103 at the lower end. At this time, since the refrigerant starts to evaporate immediately after flowing into the inlet pipe 102, the temperature of the refrigerant pipe 101 and the heat exchange fins 105 near the inlet pipe 102 becomes the lowest and gradually approaches the lower outlet pipe 103. Temperature tends to rise.

Accordingly, in the conventional cooler 100, since the refrigerant is already superheated at the lower portion of the cooler 100 shown in FIG. 3C, it hardly exerts a cooling effect. Therefore, the heat exchange area of the cooler 100 in the portion C hardly contributes to the cooling operation, and is wasted.

The moisture in the flowing air becomes frost due to the cooling action of the cooler 100 and adheres to the refrigerant pipe 101 or the heat exchange fins 105. As shown in FIG. 3, the air flows from bottom to top. In this case, as described above, since the cooling effect is hardly exerted in the portion C, frost formation grows from an intermediate portion (the portion indicated by B in FIG. 3) of the cooler 100 which is a boundary where the temperature of the refrigerant starts to rise. Then, the frost gradually spreads from the portion B to the upper part of the cooler 100 (portion indicated by A in FIG. 3). It becomes harder ice and more than the part.

Accordingly, the air flow passage in the cooler 100 is blocked by the frost in the portion B at a relatively early point in time. In addition, when the cooler 100 is defrosted, it is difficult to melt the ice in the portion B, so that a long time is required for defrosting.

The present invention has been made to solve the above-mentioned conventional technical problem, and can effectively utilize a heat exchange area, make frost blockage less likely to occur, and defrost in a relatively short time. It is an object of the present invention to provide a cooler that can perform the cooling.

[0010]

That is, the cooler 19 of the present invention.
Is composed of heat exchange fins 25 and refrigerant pipes 24 arranged in a meandering manner on the heat exchange fins 25 and rises.
The refrigerant pipe 24 is installed vertically in the flowing air.
Is the upper end located downstream of the circulating air at the refrigerant inlet (inlet
From the refrigerant inlet (inlet pipe) 26.
Once routed to the lower end located upstream of the passing air
Thereafter, it is returned to the upper end side again, and the refrigerant outlet (outlet pipe) 27
Are located in the middle of the upper and lower ends.
You.

According to the cooler 19 of the present invention, the rising flow
Refrigerant inlet (inlet pipe) 2 at the upper end located downstream of the passing air
The refrigerant flowing in from above 6 evaporates once while flowing
Since it reaches the lower end located on the flow side, the upper end of the cooler 19
From the bottom to the lower end.
You. The cooler 19 is installed vertically in the rising flowing air.
As a result, the heat exchange area of the cooler 19 is
You can use your body effectively. Meanwhile, to the cooler 19
The frost forms the refrigerant once it reaches the lower end on the upstream side.
From the pipe 24 or the heat exchange fins 25
It gradually grows to the upper end on the downstream side, but the refrigerant discharges from the lower end.
In the refrigerant pipe 24 reaching the mouth (outlet pipe) 27, the refrigerant
Because it is superheated steam, it is difficult for this part to frost
Become.

Therefore, the inside of the cooler 19 of the superheated steam portion
The air flow path is secured in the
Frost is dispersed without concentrating due to the cooling effect
Therefore, it is difficult to block the frost, and the low-temperature show for a relatively long time
The cooling capacity of the case and the like can be maintained. In particular, wear
Because frost is dispersed, frost tends to melt even during defrosting.
Therefore, the defrosting time can be shortened accordingly.
The refrigerant outlet (outlet pipe) 27 is connected to the upper end and the lower end of the cooler 19.
Because it is in the middle of the edge, it also eliminates the adverse effect on oil return
It becomes possible.

[0013]

Next, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view of a cooler 19 of the present invention, and FIG. 2 is a vertical sectional side view of a low-temperature showcase 1 as an embodiment in which the cooler 19 of the present invention is installed. In FIG. 2, a low-temperature showcase 1 is an open showcase for cooling and displaying refrigerated foods, for example, and is constituted by a heat-insulating wall 4 having a substantially U-shaped cross section opened at a front opening 5. The heat insulating wall 4 is a container-shaped heat insulating panel 3 having a cross section opened upward, a heat insulating panel 2 connected to the upper end of the rear wall of the heat insulating panel 3, and connected to the upper end of the heat insulating panel 2 to extend forward. The interior panel 9 is attached to the inside of the heat insulation panels 2 and 8 with a space therebetween, and the bottom plate 11 is spaced above the bottom wall of the heat insulation panel 3. Is attached.
A storage room 12 is formed inside the storage panel 9 and the bottom plate 11, and a plurality of shelves 13 are installed in the storage room 12.

A series of cold air ducts 14 are formed between the interior panel 9 and the bottom plate 11 and the heat insulating panels 2, 3 and 8, and the cold air ducts 14 are formed at the upper edge of the front opening 5 of the heat insulating wall 4. It is open at a discharge port 16 and a suction port 17 formed at the lower edge of the opening 5. In the cool air duct 14 on the front surface of the rear wall of the heat insulating panel 2 and the heat insulating panel 3, a cooler 19 of the present invention, which constitutes a well-known refrigeration cycle together with a compressor, a condenser and a pressure reducing device (not shown), is vertically installed. A suction type blower 21 is provided in the cool air duct 14 below the bottom plate 11.
Is installed.

The operation of the blower 21 causes the storage room 12
As shown by the arrow in FIG. 2, the air is sucked into the cool air duct 14 from the suction port 17 and rises. After being cooled by exchanging heat with the cooler 19, the air is discharged from the discharge port 16 toward the suction port 17. Is done. The discharged cool air forms an air curtain extending from the discharge port 16 to the suction port 17 to suppress the invasion of the outside air into the storage room 12, and a part of the air is caught in the storage room 12 to keep the inside at a predetermined refrigeration temperature. It cools down.

Next, in FIG. 1, the cooler 19 of the present invention is a so-called plate fin type heat exchanger, and a plurality of heat exchange fins 25 made of an aluminum thin plate and meandering through the heat exchange fins 25. And a refrigerant pipe 24 arranged in a shape. This refrigerant pipe 24 is connected to an inlet pipe 26 (refrigerant inlet) composed of a branch pipe arranged at the upper end of a cooler 19 located downstream of the flowing air (indicated by an arrow in FIG. 1) in the cool air duct 14. After being once routed to the lower end of the cooler 19 located on the upstream side of the circulating air once in two rows spaced apart from each other, it is returned to the upper end direction again, which also comprises a branch pipe. The outlet pipe 27 (refrigerant outlet) is located at an intermediate portion of the cooler 19, which is an intermediate portion between the downstream side and the upstream side.

The high-temperature and high-pressure refrigerant discharged from the compressor is condensed in the condenser, decompressed by a decompression device, and then supplied to a cooler 19 through an inlet pipe 26 at an upper end.
The refrigerant is diverted and evaporated while flowing down the upper part of the cooler 19 (the part indicated by D in FIG. 1).
9, the lower part (part shown by E in FIG. 1), rises again in the refrigerant pipe 24 (part shown by F in FIG. 1) provided in parallel with this E part, and passes through the outlet pipe 27 in the middle part. leak.

At this time, since the refrigerant starts to evaporate immediately after flowing into the inlet pipe 26, the temperatures of the refrigerant pipe 24 and the heat exchange fins 25 in the portion D near the inlet pipe 26 become lowest. However, since the refrigerant pipe 24 is temporarily lowered to the lower E portion immediately after passing through the D portion, the cooling function of the refrigerant is still maintained in the E portion. Then, from the time when the refrigerant has passed through the portion E, the refrigerant becomes superheated steam, reaches the portion F, and rises there to reach the outlet pipe 27.

Therefore, in the cooler 19 of the present invention,
Since the cooling effect is exerted in a wide range from the upper part (downstream of the flowing air) D to the lower part (upstream of the flowing air) E, the entire heat exchange area of the cooler 19 can be effectively used. Will be available. On the other hand, the moisture in the circulating air begins to adhere and grow from the refrigerant pipe 24 or the heat exchange fins 25 in the low temperature portion E located on the upstream side, and gradually spreads and grows to the portion D. As described above, since the refrigerant is superheated in the portion F of this portion, it is difficult for this portion to be frosted.

Therefore, since the air flow passage is secured in the cooler 19 in the F portion, the air can easily flow through the cooler 19 even during the frost growth process. Further, as described above, since the cooling action is exerted in a wide range, the frost is dispersed from the portion E to the portion D without being concentrated, so that the cooler 19 is hardly clogged with the frost, and the frost is hardly blocked. Long time storage room 1
2 can be maintained.

Here, when the cooler 19 is installed vertically, if the position of the outlet pipe 27 is too high, the lubricating oil (compressor oil) in the refrigerant is stored in the refrigerant pipe 24 of the F portion, and Therefore, it is assumed that the position of the outlet pipe 27 is set to an appropriate position in consideration of the adverse effect on the oil return. Further, the frost of the cooler 19 is melted and removed by subsequently stopping the compressor (off-cycle defrost) or directly supplying a high-temperature refrigerant from the compressor (hot gas defrost). Because frost formation is dispersed like
The frost is not hard and easy to melt, and the defrosting time is shortened accordingly. Therefore, the temperature rise in the storage room 12 at the time of defrosting can be suppressed low.

In the embodiment, the present invention is applied to a low-temperature showcase.
But not limited to refrigerators and other empty
It is also effective for conditioning equipment.

[0023]

According to the present invention, as described above,
Inlet at the top of the cooler located downstream of the flowing air
The refrigerant flowing from
From the top to the bottom of the cooler.
The cooling effect can be maintained in the crossing part. And
The cooler is installed vertically in the rising flowing air.
As a result, the entire heat exchange area of the cooler can be used effectively.
Become like In addition, the frost on the cooler is
Adhesive growth begins from the part reaching the lower end on the flow side, and gradually becomes downstream
Grows to the upper end of the side, but from the lower end to the refrigerant outlet
Since the refrigerant is superheated vapor in the refrigerant pipe for
It becomes difficult for frost to adhere to the part.

Therefore, an empty space is provided in the cooler of the superheated steam portion.
Airflow passages are secured, and cooling is performed over a wide area as described above.
The frosting is dispersed without concentration due to the effect
Frost blockage is difficult, and low-temperature showcase
The cooling capacity of the heat source can be maintained. In particular, frost formation
Because it is dispersed, frost tends to melt even during defrosting
Therefore, it is possible to shorten the defrosting time,
Temperature rise in the storage room of the low-temperature showcase
Can be suppressed. The refrigerant outlet is cold.
In the middle of the upper and lower ends of
The adverse effects can be eliminated.

[Brief description of the drawings]

FIG. 1 is a side view of a cooler according to the present invention.

FIG. 2 is a vertical sectional side view of a low-temperature showcase as an embodiment in which the cooler of the present invention is installed.

FIG. 3 is a side view of a conventional cooler.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low-temperature showcase 12 Storage room 14 Cold air duct 19 Cooler 24 Refrigerant piping 25 Heat exchange fin 26 Inlet pipe 27 Outlet pipe

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F25B 39/02

Claims (1)

(57) [Claims] 1. An ascending flow comprising a heat exchange fin and a refrigerant pipe arranged in a meandering manner on the heat exchange fin.
In the cooler vertically installed in the air, the refrigerant pipe,
The upper end located downstream of the circulating air is a refrigerant inlet,
From the refrigerant inlet to the lower end located upstream of the circulating air
And then returned to the upper end side again,
Exits are located midway between the top and bottom
A cooler characterized by: