JP4148584B2 - Cooling storage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce energy loss by effectively cooling the inside of a chamber and eliminate the heed of the execution of defrosting operation of a cooler. SOLUTION: A cooling storage chamber is adapted such that there are provided a compressor, a condenser, a pressure reducer, a cooler, and an air fan for the cooler, wherein a controller interrupts the operation of the compressor based upon a temperature difference in the chamber with respect to set temperature. In the cooling storage chamber, the controller operates the air fan for the cooler only in the case where cooler temperature is lower than the temperature in the chamber.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cooling storage such as a refrigerator or a freezer.
[0002]
[Prior art]
2. Description of the Related Art Generally, a cooling storage is known that includes a compressor, a condenser, a decompression device, and a cooler (evaporator) to form a refrigeration circuit, and cools the interior of the warehouse with the evaporator.
[0003]
In the refrigeration circuit, heat is deprived by forcibly changing the pressure of the refrigerant using a compressor or a decompression device. In the cooling storage as described above, the liquid refrigerant whose pressure is reduced by the decompression device absorbs the heat in the warehouse by being vaporized by the cooler, and the gas refrigerant whose pressure is increased by the compressor is condensed. The heat of the refrigerant is dissipated to the outside by being liquefied by the vessel. By periodically repeating these series of operations, the heat in the cabinet is radiated to the outside.
[0004]
As shown in FIG. 4, a general compressor is operated / stopped by operating the compressor (ON operation) when the internal temperature of the cooling storage reaches (set temperature + α) ° C. (point a in FIG. 4). Then, the compressor is controlled to be stopped (OFF operation) when the internal temperature reaches (set temperature−α) ° C. (point b in FIG. 4). Here, α is a constant set according to the specification of the device. Therefore, the refrigerant temperature (cooler temperature) in the cooler periodically changes in the range of {(set temperature) ± (α + β)} ° C., where β is the maximum temperature difference between the cooler temperature and the internal temperature. To do.
[0005]
The cooler blower that circulates the air (cold air) cooled by the cooler in the refrigerator is always operated (ON operation) regardless of the operation / stop of the compressor, the internal temperature, or the cooler temperature.
[0006]
[Problems to be solved by the invention]
In the cooling storage as described above, when the compressor is stopped due to the temperature difference between the set temperature and the internal temperature, as shown in FIG. 4, the cooler temperature starts from the moment when the compressor is stopped (point b in FIG. 4). 4 rises rapidly with the point c in FIG. 4 as the lowest point, and immediately after that, becomes the internal temperature or higher. This is because the high-temperature and high-pressure gas refrigerant in the compressor leaks and flows into the cooler when the compressor is stopped. At this time, since the cooler fan is operated, the internal temperature also rises due to the rise in the cooler temperature. That is, the internal temperature periodically changes in the vicinity of a range of approximately (set temperature ± α) ° C. so as to always follow the change in the cooler temperature.
[0007]
Therefore, even if the compressor is operated (point a in FIG. 4) and the cooler temperature starts to decrease with the point d in FIG. 4 as the uppermost point, the internal temperature does not necessarily decrease. When the compressor is stopped (point b in FIG. 4) and the cooler temperature starts to rise from the point c, the internal temperature rises rapidly following the cooler temperature. Thus, not only the inside of a store | warehouse | chamber cannot be cooled efficiently but an energy loss is large, and the start / stop of a compressor becomes frequent and energy consumption will increase.
[0008]
Moreover, in the conventional cooling storage, in order to prevent that a frost adheres to a cooler and a cooling function is impaired, it is necessary to perform a defrosting operation | movement of a cooler regularly. In order to carry out this defrosting operation, the cooler temperature must be increased intentionally, so that the internal temperature rises during this defrosting operation, and energy loss increases.
[0009]
The object of the present invention has been made in consideration of the above-mentioned circumstances, and provides a cooling storage that can cool the interior efficiently and reduce energy loss, and can eliminate the need for the defrosting operation of the cooler. There is to do.
[0010]
[Means for Solving the Problems]
The invention described in claim 1 includes a compressor, a condenser, a decompression device, a cooler, and a fan for the cooler, and the control device is based on a temperature difference of the internal temperature with respect to the set temperature, and the blower for the compressor and the cooler. In the cooling storage that operates and stops the compressor , the controller controls the cooler blower and stops the compressor when the cooler temperature is lower than the internal temperature after the compressor is operated. Thereafter, when the cooler temperature becomes higher than the internal temperature, the operation and stop of the cooler fan are repeatedly controlled so that the cooler fan is stopped .
[0011]
The invention described in claim 1 has the following action.
[0012]
Since the cooler blower is operated only when the cooler temperature of the cooler is equal to or lower than the internal temperature, the internal temperature can be quickly lowered to a desired temperature range. In addition, when the cooler temperature of the cooler is higher than the internal temperature, the cooler blower is stopped. At this time, air around the cooler having a temperature higher than the internal temperature is supplied into the internal store. Therefore, the rise in the internal temperature can be moderated. As a result, the interior can be efficiently cooled and energy loss can be reduced.
[0013]
Also, when the compressor is stopped and the cooler temperature of the cooler is higher than the internal temperature, the cooler blower is stopped. At this time, the cooler is supplied with high-temperature and high-pressure gas from the stopped compressor. The refrigerant leaks and flows, and the liquid refrigerant from the condenser flows without being depressurized even after passing through the decompression device. Thus, when the compressor and cooler blower are stopped, the heat of the compressor and condenser is transferred to the cooler and the temperature of the cooler rises, so that the frost adhering to the cooler can be naturally dissolved and cooled. It is possible to eliminate the need for defrosting operation.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0015]
In FIG. 1, a cooling storage 1 is a cooling storage such as a commercial refrigerator. The cooling storage 1 includes a heat insulating box 7 having a heat insulating door 5, and a machine room 3 is formed on the heat insulating box 7. Inside the machine room 3, a compressor 13 (rotary compressor), a condenser 15 and a condenser blower 17 constituting the refrigeration apparatus 11 are housed, and these are mounted on the upper surface of a mounting base 19 made of a heat insulating member. Is provided.
[0016]
In addition, a grill 25 is disposed on the front surface of the machine room 3, and a part of the control panel 23 storing the control device 21 is attached to the outside of the grill 25 so as to be exposed to the outside.
[0017]
The storage 27 of the heat insulating box 7 is provided with a cooler 29 and a cooler blower 31 constituting the refrigeration apparatus 11, and these are provided on the lower surface of the mounting base 19. In the storage 27, a storage temperature sensor 33 is provided, and shelves 35 (net racks) for placing food and the like are provided in three stages. The internal temperature sensor 33 detects the internal temperature of the storage 27.
[0018]
The cooler 29 is provided with a cooler temperature sensor 37 that detects the temperature of the refrigerant in the cooler 29 (hereinafter referred to as “cooler temperature”). In addition, at the lower part of the cooler 29, an defining plate 39 that defines the periphery of the cooler 29 and the interior of the storage 27 is provided. The air (cold air) around the cooler 29 surrounded by the inside of the defining plate 39 circulates in the storage 27 as indicated by the solid arrow by the action of the cooling fan 31.
[0019]
The refrigerant circuit of the refrigeration apparatus 11 is configured as shown in FIG.
[0020]
The compressor 13, the condenser 15, the decompressor 16, the cooler 29, and the check valve 30 are connected by the refrigerant pipe 12, and the refrigerant 18 discharged from the compressor 13 is sequentially passed through the refrigerant pipe 12. Washed away. Reference numeral 17 denotes a condenser blower, and 31 denotes a cooler blower. Here, the check valve 30 prevents the high-pressure gas refrigerant compressed by the compressor 13 from rapidly flowing back to the cooler 29 side when the compressor 13 (rotary compressor) is stopped. The reverse rotation of the compressor 13 is prevented.
[0021]
A control device 21 is connected to the compressor 13 via a control signal line 14, and the above-described internal temperature sensor 33 and cooler temperature sensor 37 are connected to the control device 21. The control device 21 executes the following control.
[0022]
In this embodiment, as shown in FIG. 3, the temperature difference with respect to the set temperature is set to ± α ° C. That is, the cooling storage unit controls the internal temperature to the set temperature by operating and stopping the compressor 13 at a predetermined temperature difference (± α ° C.) with respect to the set temperature. Here, α is a constant set based on the specification of the device.
[0023]
That is, the controller 21 detects the internal temperature sensor when the internal temperature detected by the internal temperature sensor 33 becomes (set temperature−α) ° C. during operation of the compressor 13 (point A in FIG. 3). Based on the detection signal from 33, a stop signal is output to the compressor 13, and the compressor 13 is stopped from the operating state (OFF operation).
[0024]
When the compressor 13 is stopped, the cooler temperature rises as will be described later. When the cooler temperature rises, the internal temperature rises and the internal temperature reaches (set temperature + α) ° C. (point in FIG. 3). B) The control device 21 outputs an operation signal to the compressor 13 based on the detection signal from the internal temperature sensor 33, and operates (ON operation) the compressor 13 from a stopped state. The internal temperature decreases due to the operation of the compressor 13. The control device 21 repeats the operation and stop of the compressor 13 as described above.
[0025]
By the way, when the compressor 13 is operated, the cooler temperature of the cooler 29 rapidly decreases, and when the internal temperature becomes (set temperature−α) ° C. (point A in FIG. 3), {(set Temperature) − (α + β)} (point C in FIG. 3). Here, β is the maximum temperature difference between the cooler temperature and the internal temperature.
[0026]
When the compressor 13 is stopped, the high-temperature and high-pressure gas refrigerant from the stopped compressor 13 leaks the check valve 30 in FIG. 2 and flows into the cooler 29, and the liquid refrigerant from the condenser 15 is depressurized. Even after passing through the device 16, it flows into the cooler 29 without being reduced in pressure. For this reason, the cooler temperature of the cooler 29 rises rapidly and reaches point D in FIG. This cooler temperature is maintained at a constant high temperature state (described later) because the cooler blower 31 is also stopped when the compressor 13 is stopped, and at the start of operation of the compressor 13 (point E in FIG. 3). It starts to descend and continues to descend rapidly during the operation of the compressor 13.
[0027]
On the other hand, the control device 21 operates the cooler blower 31 only when the cooler temperature is equal to or lower than the internal temperature, and stops the cooler blower 31 when the cooler temperature is higher than the internal temperature.
[0028]
That is, the controller 21 stops the compressor 13 (point A and point C in FIG. 3), and then the cooler temperature becomes higher than the internal temperature based on the detection signal from the cooler temperature sensor 37. Sometimes (point F in FIG. 3), a stop signal is output to the cooler blower 31 to stop the cooler blower 31. Further, the control device 21 operates the compressor 13 (points B and E in FIG. 3), and then, based on the detection signal from the cooler temperature sensor 37, the cooler temperature becomes lower than the internal temperature. (Point G in FIG. 3), an operation signal is output to the cooler blower 31 to cause the cooler blower 31 to operate. The control device 21 repeatedly controls the operation and stop of such a cooling fan 31. Naturally, at the beginning of the operation of the cooling storage 1, the control device 21 operates the cooler blower 31 because the cooler temperature becomes equal to or lower than the internal temperature due to the operation of the compressor 13.
[0029]
Here, the air temperature inside the defining plate 39 is substantially equal to the cooler temperature of the cooler 29. For this reason, air (cold air) inside the separating plate 39 is fed into the storage 27 by the operation of the cooling fan 31 performed only when the cooler temperature is equal to or lower than the internal temperature. Since it is circulated, the internal temperature is rapidly cooled to a temperature close to the cooler temperature.
[0030]
According to the above embodiment, the following effects (1) to (5) are achieved.
[0031]
(1) Since the cooler blower 31 is operated only when the cooler temperature of the cooler 29 is equal to or lower than the internal temperature of the storage 27, the internal temperature of the storage 27 is quickly lowered to a desired temperature range. Can do. Further, when the cooler temperature of the cooler 29 is higher than the internal temperature of the storage 27, the cooler blower 31 is stopped. At this time, the surroundings of the cooler 29 whose temperature is higher than the internal temperature of the storage 27 The air inside the defining plate 39 is not supplied to the inside of the storage 27, and the temperature inside the storage 27 can be moderately increased. As a result, the inside of the storage 27 can be efficiently cooled and energy loss can be reduced.
[0032]
(2) Since the inside of the storage 27 is efficiently cooled, it is possible to suppress a decrease in the life of the compressor 13 due to frequent start and stop of the compressor 13, and further it is possible to reduce energy consumption.
[0033]
(3) The operation time of the cooler blower 31 can be reduced by stopping the cooler blower 31, and the operation time of the compressor 13 can be shortened by efficiently cooling the inside of the storage 27. Also from these things, energy consumption can be suppressed.
[0034]
(4) When the cooler temperature of the cooler 29 is the lowest and the compressor 13 is stopped (point C in FIG. 3), the cooler temperature is lower than the internal temperature of the storage 27. 31 is in an operating state. For this reason, cold air continues to be fed into the storage 27 by the cooler blower 31, improving the cooling efficiency of the refrigeration apparatus 11, and preventing variations in the temperature of each part in the storage 27 at this time.
[0035]
(5) When the compressor 13 is stopped and the cooler temperature of the cooler 29 is higher than the internal temperature of the storage 27, the cooler blower 31 is stopped. At this time, the cooler 29 is stopped. The high-temperature and high-pressure gas refrigerant leaks through the check valve 30 and flows from the compressor 13, and the liquid refrigerant from the condenser 15 flows without being decompressed even after passing through the decompressor 16. Thus, when the compressor 13 and the cooler blower 31 are stopped, the heat of the compressor 13 and the condenser 15 is transferred to the cooler 29 and the temperature of the cooler 29 rises, so that it adheres to the cooler 29. The frost thus melted can be naturally melted, and the defrosting operation of the cooler 29 can be dispensed with.
[0036]
As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this.
[0037]
【The invention's effect】
As described above, according to the cooling storage according to the present invention, the control device operates the cooler fan only when the cooler temperature of the cooler is equal to or lower than the cooler temperature, thereby efficiently cooling the cooler. As a result, energy loss can be reduced, and the defrosting operation of the cooler can be omitted.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an embodiment of a cooling storage according to the present invention.
FIG. 2 is a circuit diagram showing a refrigeration apparatus in the cooling storage of FIG.
FIG. 3 is a time flowchart showing the internal temperature and cooler temperature in the cooling storage of FIG. 1;
FIG. 4 is a time flowchart showing the internal temperature and cooler temperature in a conventional cooling storage.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cooling storage 11 Refrigeration apparatus 13 Compressor 15 Condenser 16 Depressurization apparatus 21 Control apparatus 27 Storage 29 Cooler 31 Cooler blower 33 Internal temperature sensor 37 Cooler temperature sensor

Claims (1)

In the cooling storage that includes a compressor, a condenser, a decompression device, a cooler, and a fan for the cooler, and the control device operates and stops the fan for the compressor and the cooler based on the temperature difference of the internal temperature with respect to the set temperature.
After the compressor is operated, when the cooler temperature is equal to or lower than the internal temperature , the control device operates the cooler blower and stops the compressor, and then the cooler temperature is the internal temperature. When it becomes higher than, the operation and stop of the cooling fan are repeatedly controlled so as to stop the cooling fan.
Cooling storage characterized by that.

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