CN112237357B

CN112237357B - Display cabinet

Info

Publication number: CN112237357B
Application number: CN202010227356.4A
Authority: CN
Inventors: 木下卓; 渡边健
Original assignee: Fuji Electric Co Ltd
Current assignee: Fuji Electric Co Ltd
Priority date: 2019-07-19
Filing date: 2020-03-27
Publication date: 2022-12-13
Anticipated expiration: 2040-03-27
Also published as: CN112237357A; JP2021016518A

Abstract

The display case of the present invention can reduce the amount of frost formation in the evaporator. The showcase includes: a storage chamber (14) in which a plurality of commodity racks (19) are vertically arranged on the front side of a back panel (12 a) extending in the vertical direction; a blowing fan (18) which causes air to pass through a blowing outlet (17) opened at the front upper part of the containing chamber and a suction inlet (16) opened at the front lower part and circulates between a ventilation path (15) communicated to the containing chamber and the containing chamber; and an evaporator (20) provided in the ventilation path and cooling air passing through the ventilation path, wherein the goods placed in the goods placement rack are cooled to a desired temperature state by cooling the internal atmosphere of the storage chamber, and the commodity placement rack is provided with a cooler (21) which is provided on the upstream side of the evaporator in the air passing direction in the ventilation path and cools the air passing through the periphery of the evaporator to a temperature lower than that when the air passes through the suction port and higher than 0 ℃.

Description

Display cabinet

Technical Field

The present invention relates to a display case, and more particularly, to a display case that cools down commodities placed on commodity racks to a desired temperature state.

Background

Conventionally, as a showcase for cooling a commodity placed in a commodity rack to a desired temperature state, a showcase has been known.

For example, a plurality of commodity racks are provided in the storage chamber of the cabinet main body so as to be arranged in the vertical direction, and commodities are placed and displayed on the respective commodity racks. Further, a ventilation path through which air sucked through a suction port provided at a lower front portion of the storage chamber passes is formed inside the cabinet main body and outside the storage chamber. An evaporator is provided in the ventilation path, and cools air passing by driving of a blower fan provided therein, and the air cooled by the evaporator is blown out from a blow-out port provided in an upper portion in front of the storage chamber.

In the above-described showcase, the inside atmosphere of the storage chamber is cooled, whereby the commodities placed on the commodity placement frame can be cooled to a desired temperature state (see, for example, patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2015-116202

Disclosure of Invention

Technical problem to be solved by the invention

In the above-mentioned display case, when the goods placed on the goods shelf are cooled, the refrigerant passing through the evaporator is generally less than 0 ℃. Therefore, when the air passing through the ventilation path is cooled by heat exchange with the refrigerant in the evaporator, frost formation occurs in which moisture adheres to the surface of the evaporator as frost. Such frost formation is undesirable because it causes a reduction in the air cooling performance of the evaporator. Thus, the defrosting operation for defrosting is performed periodically.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a display case capable of reducing the amount of frost formation in an evaporator.

Technical scheme for solving technical problem

In order to achieve the above object, the display case of the present invention comprises: a storage chamber in which a plurality of commodity racks are vertically disposed in front of a rear plate extending in the vertical direction; a blower fan that circulates air between a ventilation path communicating with the storage chamber and the storage chamber, the blower fan passing through a blow-out port that opens at an upper front portion of the storage chamber and a suction port that opens at a lower front portion of the storage chamber; and an evaporator that is provided in the ventilation path, cools air that has passed through the ventilation path, and cools an internal atmosphere of the storage chamber, thereby cooling the commodity placed in the commodity placement rack to a desired temperature state, wherein the commodity placement rack is provided with a cooler that is provided upstream of the evaporator in a direction of passage of air in the ventilation path, and cools air that has passed around the cooler itself to a temperature that is lower than when the air passes through the suction port and is 0 ℃ or higher.

In the display case, the cooler and the evaporator constitute a common refrigerant circuit.

Effects of the invention

According to the present invention, since the cooler provided on the upstream side in the air passage direction in the ventilation path from the evaporator cools the air passing through the cooler to a temperature lower than that when passing through the suction port and equal to or higher than 0 ℃.

Drawings

FIG. 1 is a cross-sectional side view of a display case schematically illustrating an embodiment of the present invention.

Fig. 2 is a schematic diagram schematically showing a refrigerant circuit including the evaporator and the cooler shown in fig. 1.

Fig. 3 is a schematic diagram showing the flow of the refrigerant in the refrigerant circuit shown in fig. 2.

Fig. 4 is a schematic diagram showing the flow of the refrigerant in the refrigerant circuit shown in fig. 2.

Detailed Description

Hereinafter, preferred embodiments of the showcase according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a cross-sectional side view of a display case schematically illustrating an embodiment of the present invention. The display case illustrated here is a display case that stores commodities in a store such as a supermarket or a convenience store, and is configured to include a case main body 10.

The cabinet body 10 includes a bottom portion 11, a rear portion 12, and a top portion 13, and a storage chamber 14 having an open front and both left and right sides is formed in a portion surrounded by the bottom portion 11, the rear portion 12, and the top portion 13. Further, a ventilation path 15 is provided in the cabinet main body 10 so as to be separated from the storage chamber 14. The ventilation passage 15 is formed inside the bottom surface portion 11, the rear surface portion 12, and the top surface portion 13, and includes a lower ventilation duct 15a, a rear ventilation duct 15b, and an upper ventilation duct 15c.

The lower ventilation duct 15a is formed in a portion of the bottom surface portion 11 below a bottom panel forming the bottom surface of the storage chamber 14. A suction port 16 extending in the left-right direction is formed at the front end portion of the bottom panel. That is, the suction port 16 opens at the front lower portion of the storage chamber 14.

The rear ventilation duct 15b is configured as a portion of the rear section 12 that is located rearward of the rear panel 12a that forms the rear surface of the storage chamber 14. The lower end portion of the rear ventilation duct 15b communicates with the rear end portion of the lower ventilation duct 15 a.

The upper ventilation duct 15c is configured as a portion of the top surface portion 13 above the top panel 13a configuring the top surface of the storage chamber 14. The rear end portion of the upper side ventilation duct 15c communicates with the upper end portion of the rear side ventilation duct 15b. A blow-out port 17 extending in the left-right direction is formed at the front end portion of the top panel 13 a. That is, the outlet 17 opens at the front upper portion of the storage chamber 14.

A blower fan 18 is provided inside the ventilation path 15. The blower fan 18 is for circulating air. In the showcase described above, the air sucked into the air passage 15 through the air inlet 16 is sent to the air outlet 17 by driving the blower fan 18, and the air is blown out to the storage chamber 14 through the air outlet 17, thereby circulating the air between the storage chamber 14 and the air passage 15.

In the storage chamber 14, a plurality of commodity racks 19 (6 tiers in the illustrated example) are provided in the vertical direction. The commodity shelf 19 is attached to shelf supports, not shown, provided on both right and left sides of the back panel 12a, and stores and displays commodities.

The rear ventilation duct 15b in the ventilation path 15 is provided with an evaporator 20 and a cooler 21. As shown in fig. 2, the evaporator 20 is connected in a loop shape to a compressor 22, a condenser 23, and a 1 st electronic expansion valve 24 via a refrigerant pipe 25, and constitutes a refrigerant circuit through which a refrigerant circulates.

The compressor 22 is driven in accordance with a command supplied from the control unit 30, and compresses the refrigerant when driven. Here, the control unit 30 controls the operations of the respective units of the refrigerant circuit in a unified manner based on a program and data stored in a memory, not shown. The control Unit 30 may be realized by software that is a program executed by a Processing device such as a CPU (Central Processing Unit), may be realized by hardware such as an IC (Integrated Circuit), or may be realized by both software and hardware.

The condenser 23 condenses the refrigerant compressed by the compressor 22 and dissipates heat. The 1 st electronic expansion valve 24 adjusts the opening degree in accordance with a command supplied from the control unit 30, adiabatically expands the refrigerant that has been condensed and flows in the condenser 23, and brings the refrigerant into a low-temperature low-pressure state. More specifically, the 1 st electronic expansion valve 24 decompresses the refrigerant flowing therethrough to a low-temperature and low-pressure state of less than 0 ℃.

The evaporator 20 is configured to cool the air passing through the ventilation path 15 by driving the blower fan 18 to exchange heat between the air passing through the ventilation path 15 and the refrigerant in a low-temperature and low-pressure state of less than 0 ℃ by the 1 st electronic expansion valve 24, and more specifically, by evaporating the refrigerant in a low-temperature and low-pressure state. The refrigerant evaporated by the evaporator 20 is drawn into the compressor 22 and circulated in the refrigerant circuit.

Thus, in the showcase, when the compressor 22 and the blower fan 18 are driven, the air passing through the evaporator 20 is circulated and supplied to the storage chamber 14 through the ventilation passage 15, and the storage chamber 14 is maintained at a desired refrigerating temperature.

The cooler 21 is provided below the evaporator 20. That is, the cooler 21 is provided on the upstream side of the evaporator 20 in the air passage direction in the ventilation path 15. The cooler 21 is connected to an inlet pipe 26 on the inlet side and a discharge pipe 27 on the outlet side.

The introduction pipe line 26 is provided so as to be branched at a branching point P1 of the refrigerant pipe line 25 on the upstream side of the 1 st electronic expansion valve 24, and a 2 nd electronic expansion valve 28 is provided midway therebetween. The lead-out pipe line 27 is provided so as to merge at a merging point P2 of the refrigerant pipe lines 25 on the downstream side of the evaporator 20, and a flow rate adjustment valve 29 is provided midway thereof. Thus, the cooler 21 and the evaporator 20 constitute a common refrigerant circuit.

The 2 nd electronic expansion valve 28 adjusts the opening degree in accordance with a command supplied from the control unit 30, reduces the pressure of the refrigerant condensed and flowing in the condenser 23 to a low-temperature and low-pressure state of 0 ℃ or higher (for example, about 0 to 1 ℃), and sends the refrigerant to the cooler 21. More specifically, the 2 nd electronic expansion valve 28 sends the refrigerant in a state in which the refrigerant can cool the air passing through the periphery of the cooler 21 to a temperature lower than that when passing through the suction port 16 and 0 ℃.

The flow rate adjustment valve 29 adjusts the opening degree in accordance with a command supplied from the control unit 30, and reduces the pressure of the refrigerant passing through the cooler 21, specifically, the pressure of the refrigerant reduced by the 1 st electronic expansion valve 24.

In the showcase having the above-described configuration, the control unit 30 drives the compressor 22 and adjusts the opening degrees of the 1 st electronic expansion valve 24, the 2 nd electronic expansion valve 28, and the flow rate adjustment valve 29, whereby the refrigerant circuit sends the refrigerant of less than 0 ℃ to the evaporator 20 and the refrigerant of 0 ℃ or more to the cooler 21, as shown in fig. 3. Thus, by driving the blower fan 18, the air that has passed through the suction port 16 and has been sucked into the lower ventilation duct 15a of the ventilation path 15 passes through the lower ventilation duct 15a and then passes through the rear ventilation duct 15b.

The air passing through the rear ventilation duct 15b is cooled to 0 ℃ or higher by the cooler 21, so that the steam contained in the air can be condensed and separated as water. That is, the air passing through the cooler 21 can be dehumidified. Water generated around the cooler 21 drips downward and is stored in a predetermined area.

The air dehumidified by the cooler 21 is cooled to less than 0 ℃ by the evaporator 20, and the air cooled by the evaporator 20 is blown out from the blow-out port 17 through the upper ventilation duct 15c. The air blown out from the air outlet 17 passes through the front end region of the commodity shelf 19, and is then sucked into the ventilation path 15 from the air inlet 16, whereby the air can be circulated through the storage chamber 14 and the ventilation path 15. This makes it possible to form an air curtain with the air cooled by the evaporator 20 and the cooler 21 on the front surface of the storage chamber 14.

As a result, since an air curtain is formed on the front surface of the storage chamber 14 by the air (cool air) blown out from the air outlet 17, the internal atmosphere of the storage chamber 14 can be cooled, and thus the commodities in the commodity housing 19 placed in the storage chamber 14 can be cooled to a desired temperature state.

As described above, according to the showcase of the embodiment of the present invention, the cooler 21 provided on the upstream side of the evaporator 20 in the air passage direction of the air in the air passage 15 cools the air passing through the cooler to the temperature of 0 ℃.

This can reduce the amount of frost formation in the evaporator 20, and therefore can reduce the number of defrosting operations for removing frost adhering to the evaporator 20, or reduce the time required for 1 defrosting operation, and can avoid damage to merchandise placed on the merchandise rack 19.

During the defrosting operation, the controller 30 can drive the compressor 22, adjust the opening degrees of the 2 nd electronic expansion valve 28 and the flow rate adjustment valve 29, and close the 1 st electronic expansion valve 24. As a result, as shown in fig. 4, the refrigerant circuit sends the refrigerant of 0 ℃. Thus, by driving the blower fan 18, the air cooled to 0 ℃ or higher by the cooler 21 can be sent to the storage chamber 14, and the temperature of the commodity placed on the commodity placement rack 19 can be prevented from rapidly rising, and damage to the commodity can be suppressed.

The preferred embodiments of the present invention have been described above, but the present invention is not limited thereto, and various modifications can be made.

In the above-described embodiment, the cooler 21 and the evaporator 20 constitute a common refrigerant circuit, but in the present invention, the cooler may not constitute a common refrigerant circuit with the evaporator, and may be any one as long as it can cool the air passing through its surroundings to a temperature lower than that when passing through the suction port and 0 ℃.

In the above-described embodiment, the 1 st electronic expansion valve 24 is closed to restrict the delivery of the refrigerant to the evaporator 20 during the defrosting operation, but in the present invention, the delivery of the refrigerant to the evaporator may be restricted without adjusting the opening degree of the 1 st electronic expansion valve by closing a solenoid valve provided upstream of the 1 st electronic expansion valve.

Description of the reference symbols

10. Cabinet main body

12a back panel

14. Storage chamber

15. Ventilation path

15a lower side ventilation duct

15b rear side ventilation duct

15c upper side ventilation duct

16. Suction inlet

17. Blow-out opening

18. Air supply fan

19. Commodity placing rack

20. Evaporator with a heat exchanger

21. Cooling device

22. Compressor with a compressor housing having a plurality of compressor blades

23. Condenser

24. No. 1 electronic expansion valve

25. Refrigerant pipeline

26. Leading-in pipeline

27. Export pipeline

28. No. 2 electronic expansion valve

29. Flow regulating valve

30. A control unit.

Claims

1. A display case, comprising:

a storage chamber (14) in which a plurality of commodity racks (19) are vertically disposed on the front side of a back panel (12 a) extending vertically;

a blower fan (18) that circulates air between a ventilation path (15) that communicates with the storage chamber (14) and the storage chamber (14) by passing the air through a blow-out port (17) that opens at the upper front portion of the storage chamber (14) and a suction port (16) that opens at the lower front portion; and

an evaporator (20) that is provided in the ventilation path (15) and cools air passing through the ventilation path (15),

cooling the goods placed on the goods placing shelf (19) to a desired temperature state by cooling the internal atmosphere of the storage chamber (14),

the display cabinet comprises a cooler (21) which is arranged on the upstream side of the evaporator (20) in the passing direction of the air in the ventilation path (15) and cools the air passing through the periphery of the cooler to be lower in temperature and more than 0 ℃ than the air passing through the suction opening (16),

a refrigerant circuit for circulating a refrigerant is configured by connecting a compressor (22), a condenser (23), a 1 st electronic expansion valve (24) and an evaporator (20) in this order through a refrigerant pipe (25), wherein the 1 st electronic expansion valve (24) decompresses the refrigerant condensed and flowing by the condenser (23) and sets the refrigerant to a low-temperature and low-pressure state of less than 0 ℃,

the cooler (21) is connected at the inlet side with an inlet pipe (26) and at the outlet side with an outlet pipe (27),

the introduction line (26) is provided so as to branch from a 1 st branch point (P1) of the refrigerant line (25) on the upstream side of the 1 st electronic expansion valve (24), and a 2 nd electronic expansion valve (28) is provided midway in the introduction line, and the 2 nd electronic expansion valve (28) reduces the pressure of the refrigerant flowing while being condensed by the condenser (23) to a low-temperature and low-pressure state of 0 ℃ or higher, and sends the refrigerant to the cooler (21),

the lead-out line (27) is provided so as to join at a 2 nd junction (P2) of the refrigerant line (25) on the downstream side of the evaporator (20), and a flow rate adjustment valve (29) is provided midway in the lead-out line, the flow rate adjustment valve (29) reducing the pressure of the refrigerant passing through the cooler (21) to the pressure of the refrigerant reduced by the 1 st electronic expansion valve (24),

the cooler (21) and the evaporator (20) together form a common refrigerant circuit.