JP2013242104A - Showcase - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a showcase capable of avoiding deterioration of performance of a heat exchanger and achieving a stable cooling capability without using a great deal of costs even if refrigerant piping passing through fins are widely arranged for preventing accumulation of air caused by frost formation.SOLUTION: A showcase includes a blower, and a heat exchanger passing air from the blower. Refrigerant piping provided in an upwind side of fins of the heat exchanger is coarsely arranged, and refrigerant piping provided in a downwind side of the fins is arranged more densely than the refrigerant piping provided in the upwind side of the fins.

Description

The present invention relates to a showcase for storing food and the like in a fresh state for a long time when the food and the like are sold at a store.

In recent years, in the air conditioning industry, a transition to an alternative refrigerant that does not destroy the ozone layer has been promoted from the viewpoint of environmental protection and the like, and development using a new refrigerant is also promoted in the showcase industry.

When a new refrigerant such as CO ₂ is used instead of the conventional refrigerant (for example, R404a, etc.), the pressure loss may be larger than that of the conventional refrigerant. Large refrigerant piping must be used. However, in order to use refrigerant pipes with larger pipe diameters than before, custom-made refrigerant pipes must be prepared, and expansion equipment for expanding the pipe diameter of refrigerant pipes and hairpin headers that curve refrigerant pipes Enormous capital investment costs such as equipment are generated.

Therefore, as a method to reduce the capital investment cost, it is possible to divert heat exchangers equipped with refrigerant pipes with large diameters for new refrigerants already used in air conditioners, but in the case of heat exchangers dedicated to air conditioners Since the intervals between the refrigerant pipes passing through the fins are narrow, frost is likely to be formed, and the performance of the heat exchanger may be deteriorated.

That is, in the case of an open showcase with an open front side, outside air can freely enter the storage chamber, so moisture contained in the outside air is cooled in contact with the fins or refrigerant piping of the heat exchanger, and frost is generated. It may be attached. Moreover, since air with a higher water content flows on the leeward side of the fins than on the leeward side of the fins of the heat exchanger, frost is easily formed. In particular, when the straight pipe portions of a plurality of refrigerant pipes are densely arranged in the heat exchanger, the gap between the straight pipe portions is reduced, the air passing through the gap portion is overcooled, and frost is generated. There is a possibility that the performance of the heat exchanger may be deteriorated because air cannot pass through by being easily attached.

Therefore, heat exchangers dedicated to showcases tend to have wider intervals between the refrigerant pipes that pass through the fins compared to heat exchangers such as air conditioners. When using heat exchangers dedicated to air conditioners, they pass through the fins. Since the interval between the refrigerant pipes is narrow, there is a problem that frost is easily formed and the performance of the heat exchanger is deteriorated.

Therefore, the holes are formed in a plurality of rows along a straight line that forms an angle of 60 degrees with respect to the flow direction of the air to be cooled, so that the straight pipe portion of the refrigerant pipe is not concentrated in part. By arranging the refrigerant pipes on the fins so that the straight pipe parts of the refrigerant pipes are spaced apart every other row, the distance between the straight pipe parts is increased, air is prevented from overcooling, and frost is attached. A showcase that makes it difficult has been proposed (see, for example, Patent Document 1).

JP 2008-128562 A (3rd page, FIG. 7)

However, with the conventional arrangement of refrigerant pipes in showcases, the number of refrigerant pipes that pass through the fins is reduced by the distance between the straight pipe parts, so the number of refrigerant pipes that are struck by captured air is reduced and heat exchange is performed. There was a problem that the heat exchange efficiency performance of the vessel would decrease. As a solution to solve this problem, a method of increasing the number of refrigerant pipes is also conceivable. However, the area of the fins must be increased by increasing the number of refrigerant pipes, and there is a possibility that the showcase body becomes large. In spite of reducing the capital investment cost by diverting the heat exchanger for use, there is a problem that a large amount of costs such as material costs and processing costs are generated as a result.

The present invention has been made in order to solve the above-described problems, and even if the refrigerant pipes passing through the fins are arranged with a wide interval in order to prevent stagnation of air due to frost formation, a large cost is required. It is another object of the present invention to provide a showcase capable of realizing a stable cooling performance while avoiding a decrease in performance of a heat exchanger.

In the showcase according to the present invention, the refrigerant pipes provided on the leeward side of the fins of the heat exchanger are arranged roughly and the refrigerant pipes provided on the leeward side of the fins are provided on the leeward side of the fins. It is arranged more densely.

In the showcase according to the present invention, the refrigerant pipes provided on the leeward side of the fins are arranged densely, and the refrigerant pipes provided on the leeward side of the fins are arranged closely so that air with a high water content flows. On the leeward side of the fins, the refrigerant piping is widened to prevent stagnation of air due to frost formation. By arranging more pipes than on the windward side and increasing the heat exchange efficiency of the air, it is possible to achieve a stable cooling performance by avoiding a decrease in the performance of the heat exchanger without incurring significant costs. .

It is a perspective view which shows the showcase which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the structure of the showcase which concerns on Embodiment 1 of this invention. It is a figure which shows the cooler of the showcase which concerns on Embodiment 1 of this invention. It is a figure which shows the cooling part of the showcase which concerns on Embodiment 1 of this invention. It is the figure which expanded the cooling part of the showcase which concerns on Embodiment 1 of this invention. It is a figure which shows the left side surface of the cooling part of the showcase which concerns on Embodiment 1 of this invention.

Hereinafter, preferred embodiments of a showcase according to the present invention will be described with reference to the drawings. Note that the present invention is not limited by these embodiments.

Embodiment 1 FIG.
FIG. 1 shows a showcase according to an embodiment of the present invention as viewed obliquely from the front right side, FIG. 2 shows an internal configuration of the showcase according to the present embodiment, and FIG. 3 shows an embodiment of the present invention. 4 to 6 show a cooling unit of the showcase according to the embodiment of the present invention.

The showcase 1 described in the present embodiment is of a multistage open type with the front surface opened as shown in FIGS. The showcase 1 includes a showcase body 2 having an open front surface, a ventilation path 3 provided inside the showcase body 2 and formed along the top surface, the back surface, and the bottom surface of the showcase body 2. A blower 4 that is provided and sends air in the ventilation path 3 upward, and a cooler (evaporator) 5 that is provided leeward of the blower 4 and cools the air in the ventilation path 3.

The showcase body 2 is provided with a storage chamber 7 surrounded by a U-shaped heat insulating wall portion 6, and a display shelf 9 is attached to the inner wall portion 8 of the storage chamber 7. A machine room 10 having an open front is provided below the storage room 7 of the showcase body 2. The machine room 10 includes a compressor 11, a condenser 12, a throttle device 13, a heat radiating fan 14, and a control device 15. Is provided. Further, the front opening of the machine room 10 is closed by a front panel 16 in which an intake hole is formed.

The ventilation path 3 is formed between the heat insulating wall 6 and the inner wall 8, a cold air outlet 17 is formed at the upper end of the ventilation path 3, and the cold air is discharged at the lower end of the ventilation path 3. A suction port 18 is formed. Thereby, after the air sent by the blower 4 is cooled by the cooler 5, it is sent to the upper side and discharged from the cold air outlet 17 to the vicinity of the display shelf 9, while the cold air near the display shelf 9 is The air is sucked into the ventilation path 3 from the cold air inlet 18 and is again sent to the cooler 5 by the blower 4. This air circulation flow is indicated by arrows in FIG.

The cooler 5 is connected to a compressor 11 provided in the machine room 10 via a refrigerant pipe 19, and a refrigeration cycle is configured between the compressor 11 and the cooler 5. The refrigeration cycle includes a refrigerant pipe 19 that sequentially connects the compressor 11, the condenser 12, the expansion device 13, and the cooler 5 in an annular manner, and CO 2 refrigerant circulates in the refrigerant pipe 19.

The refrigerant discharged from the compressor 11 is cooled by radiating heat to the air blown by the heat radiating blower 14 in the condenser 12, depressurized by the expansion device 13, evaporated by the cooler 5, and again compressed by the compressor 11. The refrigeration cycle of the showcase is formed by returning to At this time, the heat radiating fan 14 cools the refrigerant by the air taken in from the intake holes of the front panel 16, and the air after the heat exchange passes between the showcase body 2 and the heat insulating wall 6 and externally from above. Is discharged.

As shown in FIGS. 3 to 5, the cooler 5 includes a cooling unit 20 and a cover 21 provided on the front surface of the cooling unit 20, and the cooling unit 20 penetrates the plurality of fins 22 and the plurality of fins 22. It is a fin and tube type heat exchanger provided with the refrigerant | coolant piping 23 to perform and the side surface metal fitting 24 which comprises both sides.

Each of the fins 22 has a flat plate shape, and as shown in FIG. 4, the fins 22 are arranged substantially in parallel along the longitudinal direction, and are arranged with a predetermined interval therebetween. The fin 22 has a plurality of holes 25 through which the refrigerant pipe 23 is inserted, and the plurality of holes 25 are arranged in four rows in the longitudinal direction of the fin.

The plurality of hole portions 25 formed in the fin 22 are formed such that arbitrarily selected three adjacent hole portions (for example, indicated by reference numerals S1, S2, and S3 in FIG. 6) form a vertex of the triangle. The holes are arranged, and the hole pitch between the adjacent holes 25 is constant. This hole pitch coincides with the interval P1 of the U-shaped straight tube portion of the long U-shaped tube 23a.

The refrigerant pipe 23 is connected to the refrigerant pipe 19 constituting the refrigeration cycle, and as shown in FIG. 4, a plurality of long U-shaped tubes 23a and a plurality of short U-shaped tubes (first short U-shaped tube 23b, first 1 short U-shaped tube 23c) is connected by welding to form a CO2 refrigerant flow path.

In the first short U-shaped tube 23b, the interval P between the U-shaped straight tube portions matches the interval P1 between the U-shaped straight tube portions of the long U-shaped tube 23a, and the first short U-shaped tube 23c. Has a longer interval P between the U-shaped straight pipe portions than the first short U-shaped pipe 23b. By using the first short U-shaped tube 23b and the first short U-shaped tube 23c, the refrigerant pipe 23 can be configured to penetrate the plurality of fins 22 while repeating meandering.

Moreover, the pipe diameter of the refrigerant pipe 23 is the same as the pipe diameter of the refrigerant pipe 19, and the refrigerant pipe is thicker than the refrigerant pipe used in a circuit using a general refrigerant (for example, R404a). Things are used.

As shown in FIG. 6, the refrigerant pipe 23 has long U-shaped tubes 23 a inserted through the refrigerant pipe 23 on the leeward side so as to extend in two adjacent rows, and the long U-shaped tubes are inserted into all the holes 25. It arrange | positions so that 23a may be penetrated. The refrigerant pipe 23 on the leeward side easily collides with the air flowing through the ventilation path 3, and the straight pipe portion of the long U-shaped pipe 23 a is arranged densely to increase resistance to the air flowing through the ventilation path 3. The heat exchange efficiency can be increased. In addition, a first short U-shaped tube 23b having the same interval P between U-shaped straight tube portions is connected to the long U-shaped tube 23a.

Further, in the refrigerant pipe 23 on the windward side, the straight pipe portion of the long U-shaped pipe 23 a is the pitch between the hole portions 25 in the hole portions 25 in the middle two rows among the four rows of hole portions 25 formed in the fins 22. It is inserted at a longer pitch. A path through which the frosting resistance is improved and air is sent is provided in the middle row of the fins 22 by providing a pass-extracting portion in which the long U-shaped tube 23a is not inserted through the fins 22 continuously from the windward side to the leeward side. Even when frost is formed on the surface of the straight pipe portion of the long U-shaped tube 23a, the gap between the long U-shaped tubes 23a in the direction intersecting with the air flow direction is blocked and the windward side Problems such as blocking the flow of air flowing to the leeward side can be prevented.

Of the four rows of hole portions 25 formed in the fin 22, the hole portions 25 at both ends have holes 25 adjacent to the straight tube portions of the long U-shaped tubes 23 a arranged in the middle two rows. In addition, the straight tube portion of the long U-shaped tube 23a is arranged to be inserted therethrough. In this way, a path through which air is sent is formed by arranging the straight pipe portions of the long U-shaped pipe 23a so as to easily collide with the air flowing through the ventilation path 3 while providing a path-excluding portion. The resistance to the air flowing through the ventilation path 3 can be increased while the heat exchange efficiency of the air can be further increased.

In addition, about the refrigerant | coolant piping 23 of the windward side of the fin 22, either the 1st short U-shaped pipe 23b or the 1st short U-shaped pipe 23c is made into the length of the pitch of the straight pipe part of the long U-shaped pipe 23a. By selecting and connecting them together, the straight tube portion of the long U-shaped tube 23a can be arranged even at a pitch between the holes 25 or at a pitch longer than the pitch between the holes 25.

6 is a left side view of the cooling unit 20 shown in FIG. The side fitting 24 is formed with a plurality of holes 26 into which the refrigerant pipe 23 is inserted, and the inserted refrigerant pipe 23 and the side fitting 24 are fixed by welding.

Next, based on FIG. 2, the operation | movement at the time of the driving | running | working of the showcase which concerns on Embodiment 1 is demonstrated.
When the operation of the showcase 1 is started, air in the ventilation path 3 is cooled by the cooler 5, and the blower 4 is driven, so that outside air is sucked into the ventilation path 3 from the cold air inlet 18. The sucked outside air flows into the cooler 5 and collides with the refrigerant pipe 23, is absorbed by the refrigerant in the refrigerant pipe 23, exchanges heat, and becomes cold air.

At this time, the outside air passing through the gap between the long U-shaped pipes 23a having a narrow pitch on the windward side of the fins 22 is supercooled between the refrigerant pipes 23 placed at a narrow distance, and the moisture contained in the outside air Becomes frost and adheres to the long U-shaped tube 23a. Narrow gaps between the long U-shaped tubes 23a that are separated only by the pitch between the holes 25 are blocked by frost. Further, since the outside air passing through the gap between the long U-shaped pipes 23a having a wide pitch provided as a path in the middle row has a large distance between the long U-shaped pipes 23a, there is no possibility of being overcooled. The long U-shaped tube 23a frosts and flows toward the leeward side without closing the gap between the long U-shaped tubes 23a.

The outside air that has passed through the windward side of the fin 22 passes through the gap between the long U-shaped pipes 23a having a narrow pitch on the leeward side of the fin 22 and is cooled between the refrigerant pipes 23 placed at a narrow distance. Since the outside air flowing on the leeward side has already undergone heat exchange on the leeward side, the amount of moisture contained is small, and even if it adheres to the refrigerant pipe as frost, it does not grow so much, so between the long U-shaped tubes 23a There is no possibility that the narrow air gap is blocked and the flow of the outside air flowing through the cooler 5 is retained.

The outside air that has been cooled and exchanged heat by the cooling unit 5 is blown out from the outlet 17 toward the display shelf 9 through the ventilation path 3. A cold air curtain is formed in the opening of the storage chamber 7 by the cold air blown out from the air outlet 17, and the intrusion of outside air from the opening is prevented or suppressed. The cold air blown out from the cold air outlet 17 toward the vicinity of the display shelf 9 is again sucked into the ventilation path 3 from the cold air inlet 18 and circulates in the storage chamber 7 to cool the inside of the storage chamber 7.

As described above, a heat exchanger provided with a refrigerant pipe with a large pipe diameter for a new refrigerant already used in an air conditioner is diverted, and the refrigerant pipe provided on the windward side of the fin of the heat exchanger is used as a fin. Provided with a pitch wider than the pitch of the formed holes and arranged densely, and provided the refrigerant piping provided on the leeward side of the fin at the same pitch as the pitch of the holes formed in the fin, provided on the leeward side of the fin Since it is arranged more densely than the refrigerant pipe, it is possible to prevent stagnation of air due to frost formation on the leeward side of the fin, and to increase the heat exchange efficiency of air on the leeward side of the fin.

In addition, when the refrigerant pipe arrangement on the windward side of the fins of the heat exchanger is aligned with the straight pipe portion of the long U-shaped pipe 23a crossing the air flow direction, the pipe surface is frosted. In order not to block the air flow direction, the pass-extracted portion where the long U-shaped tube 23a is not inserted into the fin 22 is arranged in the middle row so as to be continuously provided from the leeward side to the leeward side. Therefore, the frosting resistance is improved and a path through which air is sent is easily formed, and the retention of air due to the frosting of the heat exchanger can be prevented.

Therefore, according to the present embodiment, air is prevented from staying due to frost adhering to the heat exchanger, and a stable cooling performance is avoided without deteriorating the performance of the heat exchanger, without incurring a great expense. Showcase can be provided.

In this embodiment, a path that forms a path through which air is sent is provided in the middle row, but a path that forms a path through which air is sent according to the direction of air flow and the performance of the heat exchanger. The position for providing the position may be shifted.

DESCRIPTION OF SYMBOLS 1 Showcase, 2 Showcase main body, 3 Ventilation channel, 4 Blower, 5 Cooler, 6 Thermal insulation wall part, 7 Storage room, 8 Inner wall part, 9 Display shelf, 10 Machine room, 11 Compressor, 12 Condenser, 13 Throttle device, 14 Fan for heat dissipation, 15 Control device, 16 Front panel, 17 Cold air outlet, 18 Cold air inlet, 19 Refrigerant piping (refrigeration cycle side), 20 Cooling unit, 21 Cover, 22 Fin, 23 Refrigerant piping (cooling) Device side), 23a long U-shaped tube, 23b first short U-shaped tube, 23c second short U-shaped tube, 24 side fittings, 25 holes (fin side), 26 holes (side fitting side)

Claims (6)

A cooler having a plurality of holes formed on the surface, a plurality of flat fins arranged at intervals, and a plurality of refrigerant pipes communicating with the holes formed in the fins;
A blower for sending air between the fins of the cooler;
With
The refrigerant piping provided on the leeward side of the fins is densely arranged, and the refrigerant piping provided on the leeward side of the fins is arranged more densely than the refrigerant piping formed on the leeward side of the fins. Showcase featured. A cooler having a plurality of holes formed on the surface, a plurality of flat fins arranged at intervals, and a plurality of refrigerant pipes communicating with the holes formed in the fins;
A blower for sending air between the fins of the cooler;
With
Refrigerant piping provided on the leeward side of the fins is arranged at a pitch equal to the pitch of the holes formed in the fins,
The showcase, wherein the refrigerant pipe provided on the windward side of the fin has a portion arranged at a pitch longer than a pitch of holes formed in the fin. Holes formed in the fins are arranged side by side along the direction of air flow from the blower, and at least one row continuously arranged from the windward side to the leeward side of the fins is inserted through the refrigerant pipe. The showcase according to claim 1, wherein the non-insertion hole is not formed. The holes formed in the fins are arranged in three or more rows along the flow direction of air from the blower,
Of the refrigerant pipes provided on the windward side of the fins, the refrigerant pipes provided in the central row of the hole portions are arranged more densely than the refrigerant pipes provided in adjacent rows. The showcase according to any one of claims 1 and 3. The holes formed in the fins are arranged in three or more rows along the flow direction of air from the blower,
Of the refrigerant pipes provided on the windward side of the fins, the refrigerant pipes provided in the central row of the hole portions have portions arranged at a longer pitch than the refrigerant pipes provided in adjacent rows. The showcase according to claim 2, wherein the showcase is characterized in that The said hole row | line | column consisting of the non-insertion hole which does not penetrate the said refrigerant | coolant piping provided in the said fin is provided so that the flow direction of the air from the said air blows may be provided. Showcase described.

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