WO2016088153A1

WO2016088153A1 - Freezing device

Info

Publication number: WO2016088153A1
Application number: PCT/JP2014/006050
Authority: WO
Inventors: 隆一郎弘野
Original assignee: 三菱電機株式会社
Priority date: 2014-12-04
Filing date: 2014-12-04
Publication date: 2016-06-09

Abstract

This freezing device is provided with: a refrigerated storage compartment 1; a refrigerant circuit 16 in which a compressor 7, a condenser 8, an expansion valve 11, and an evaporator 12 are connected in a loop; an evaporator fan 13; a trapped worker alarm switch 5 able to be turned on by a worker inside the compartment; a defrosting means 17 for eliminating frost from the evaporator 12; an operation switching means of a control device 4 for switching between refrigeration operation to refrigerate the refrigerated storage compartment 1 interior and defrost operation to eliminate frost from the evaporator 12; and a first operation control means of the control device 4, for switching to defrost operation when the trapped worker alarm switch 5 is turned on during refrigeration operation, and continuing in defrost operation when the trapped worker alarm switch 5 is turned on during defrost operation, thereby quickly raising the temperature inside the compartment and reducing the risk of endangering life when a worker has become shut inside the refrigerated storage compartment.

Description

Refrigeration equipment

This invention relates to control of a refrigeration apparatus when a person is confined in a cooling storage.

Conventionally, in large-scale cooling storages such as prefabricated refrigerators, assuming that people are accidentally trapped in the cooling storage (confinement), a switch is provided in the cooling storage, and an alarm device connected to this switch is located outside the cooling storage. Has been deployed. According to this cooling storage, when a person in the warehouse turns on the switch, the person outside the warehouse is informed that the person is confined in the warehouse (for example, see Patent Document 1). .

However, if confined during cooling operation, it may be exposed to the low temperature environment in the cooling storage for a long time. Therefore, for the purpose of reducing the possibility of falling into the above situation as much as possible, when the switch is operated, the operation of the refrigeration apparatus is stopped, and further, for defrosting attached to the unit cooler in the cooling storage. There is also known a refrigeration apparatus that energizes a heater and attempts to raise the temperature in the cooling storage as much as possible (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 8-200302 (FIG. 1) Japanese Patent Laid-Open No. 2001-280816 (FIG. 4)

In the technique of Patent Document 1, since the operation of the refrigeration apparatus is continued only by informing the outside that a person is confined in the cooling storage, the object to be cooled in the cooling storage is protected. The risk of being exposed to a low temperature environment for a long time cannot be reduced.
On the other hand, the technique of Patent Document 2 is exposed to a low temperature environment in a confined human cooling storage for a long time by energizing a defrosting heater attached to a unit cooler installed in the cooling storage. This can reduce the risk. However, there is a problem that it takes time to raise the internal temperature only by energizing the defrosting heater. Furthermore, there is a desire to protect the object to be cooled in the cooling storage to some extent while preventing a person from being exposed to the low temperature environment in the cooling storage for a long time, but there is a problem that this request cannot be met. .

The present invention has been made to solve the above-described problems. The first object is to quickly increase the internal temperature when a person is trapped in the cooling storage, and It is to obtain a refrigeration apparatus that can reduce the risk of being exposed to a low temperature environment for a long time.

Also, a second object is to obtain a refrigeration apparatus that can protect an object to be cooled in the cooling storage to some extent while preventing a person from being exposed to a low temperature environment in the cooling storage for a long time.

A refrigeration apparatus according to the present invention includes a cooling storage that is cooled by an evaporator disposed in a warehouse, a refrigerant circuit in which a compressor, a condenser, an expansion valve, and an evaporator are annularly connected in the order described, Cooling by the operation of the evaporator fan that blows air inside the evaporator to the evaporator, the confinement alarm switch that is turned on by a person in the cooling storage, the defrosting means that removes frost on the surface of the evaporator, and the operation of the refrigerant circuit Operation switching means that switches between the cooling operation for cooling the inside of the storage and the defrosting operation for removing frost on the surface of the evaporator by the operation of the defrosting means, and the operation when the confinement alarm switch is turned on during the cooling operation And a first operation control means for operating the switching means and the defrosting means to switch to the defrosting operation and for continuing the defrosting operation when the confinement alarm switch is turned on during the defrosting operation. thing It is an feature.

The refrigeration apparatus of the present invention starts the defrosting operation when the confinement alarm switch is turned on during the cooling operation, and continues the defrosting operation when the confinement alarm switch is turned on during the defrosting operation. Since it comprised as mentioned above, even if a person is confine | sealed in the cooling storage, it has the effect that the internal temperature can be raised.

It is a block diagram which shows schematic structure of the freezing apparatus in Embodiment 1, 2 of this invention. It is a control block diagram which shows the structure of the control apparatus of the said freezing apparatus. It is a flowchart which shows the control procedure by the control apparatus in Embodiment 1 of this invention. It is a figure of the graph which shows typically a time-dependent change of the inside temperature of the cooling storage in Embodiment 1 of this invention, and (a) is a figure at the time of a confinement alarm switch being turned on during cooling operation, b) is a diagram when the confinement alarm switch is turned on during the defrosting operation. It is a flowchart which shows the control procedure by the control apparatus in Embodiment 2 of this invention.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a schematic configuration of a refrigeration apparatus according to Embodiments 1 and 2 of the present invention.
In FIG. 1, a refrigeration apparatus according to this embodiment includes a condensing unit 2 disposed outside, a unit cooler 3 disposed in a cooling storage 1 that accommodates an object to be cooled, and these condensing units 2 and A control device 4 that performs various controls on the unit cooler 3, a confinement alarm switch 5 that is provided in the cooling storage 1 and is turned on by a person in the storage, and a thermistor that detects the internal temperature Example of temperature detector) 6.

The condensing unit 2 includes a compressor 7 that compresses and discharges refrigerant, a condenser 8 that performs heat exchange between the refrigerant from the compressor 7 and outdoor air, and a condenser that blows outdoor air to the condenser 8. A fan 9 is provided. The unit cooler 3 includes an expansion valve 11 that squeezes the refrigerant from the condenser 8 to reduce the pressure, an electromagnetic valve 10 disposed between the condenser 8 and the expansion valve 11, a refrigerant from the expansion valve 11, and internal air The evaporator 12 that cools the interior by performing heat exchange, the evaporator fan 13 that blows the air in the warehouse to the evaporator 12, and the frost formation on the surface of the evaporator that is disposed in the vicinity of the evaporator 12 A defrosting heater 14 that is removed by being removed is provided. The defrost heater 14 is heated to a high temperature and melts and removes frost adhering to the surface of the evaporator 12. The compressor 7, the condenser 8, the electromagnetic valve 10, the expansion valve 11, and the evaporator 12 described above are arranged in this order and are connected annularly via the refrigerant pipe 15 to constitute the refrigerant circuit 16.

As shown in FIG. 2, the control device 4 includes a microcomputer 41, a nonvolatile memory 42, a timer, a data bus, an input / output port, and the like. Input means 43A and 43B for capturing signals from the confinement alarm switch 5 and the thermistor 6 are connected to the input side of the data bus. Output means 44A to 44E for driving the compressor 7, the condenser fan 9, the evaporator fan 13, the expansion valve 11 and the like are connected to the output side of the data bus.

The microcomputer 41 includes a normal operation control means 45, an operation switching means 46, a defrosting operation control means 47, a fan control means 48, a first operation control means 49, a second operation control means 50, which will be described in detail later. And each function of the 3rd operation control means 51 is provided as program software. Each of these functions is stored in advance in the memory 42 as program data, and is extracted from the memory 42 and used in the microcomputer 41 as necessary. The memory 42 stores in advance a set temperature related to the internal temperature of the cooling storage 1.

The function of the normal operation control means 45 of the microcomputer 41 is based on the operation information (room air temperature, set temperature, refrigerant pipe temperature, etc.) obtained according to the program read from the memory 42, and the motor speed of the compressor 7 , Predetermined control is performed for the fan speed of the condenser fan 9, the opening / closing of the electromagnetic valve 10, the opening degree of the expansion valve 11, the fan speed of the evaporator fan 13, the energization power of the defrost heater 14 Is. Incidentally, in a normal refrigeration apparatus, a control device for an outdoor unit and a control device for an indoor unit are independent, and these control devices are connected via a contact or a communication line.

Next, operation | movement of this freezing apparatus is demonstrated. In the refrigeration apparatus configured as described above, the operation mode is roughly divided into a cooling operation and a defrosting operation.
In the cooling operation, the refrigerant in the refrigerant circuit 16 is made high temperature and high pressure by the compressor 7, discharged from the compressor 7, and flows into the condenser 8. The refrigerant flowing into the condenser 8 exchanges heat with the air sent from the condenser fan 9 and is condensed and liquefied. The condensed and liquefied refrigerant flows through the connection pipe 15, passes through the electromagnetic valve 10, and flows into the expansion valve 11. The refrigerant flowing into the expansion valve 11 is decompressed and expanded, and changes its state to a low-temperature and low-pressure gas-liquid two-phase refrigerant. This gas-liquid two-phase refrigerant flows into the evaporator 12, heat exchanges with the internal air sent by the evaporator fan 13, and evaporates to gasify. The evaporated gas refrigerant flows out of the evaporator 12, flows through the connection pipe 15, and is sucked again into the suction side of the compressor 7. Such a refrigeration cycle operation of the refrigerant circuit 16 is repeated. On the other hand, the cooling operation is stopped by stopping the compressor 7, the condenser fan 9 and the evaporator fan 13 of the refrigerant circuit 16 and closing the solenoid valve 10.

On the other hand, the defrosting operation is an operation mode for melting frost adhering to the surface of the evaporator 12 of the unit cooler 3. Here, for example, a heater defrosting method is adopted in which the defrosting heater 14 is energized and the frost is melted by the generated heat. That is, the defrosting means 17 is comprised from the defrosting operation control means 47 of the control apparatus 4, the output means 44C, and the defrosting heater 14 of the unit cooler 3. FIG. During such defrosting operation, the temperature of the unit cooler 3 is high in order to melt the frost. Normally, during the defrosting operation, the evaporator fan 13 of the unit cooler 3 is stopped because it is not desired to circulate the warmed air in the cooling storage 1.

FIG. 3 is a flowchart showing the control in Embodiment 1 of the present invention, and the control procedure will be described according to this flowchart.
When the controller 4 detects that the confinement alarm switch 5 is turned on by a person inside the refrigerator during the operation of the refrigeration apparatus, the controller 4 first checks the operating state (step 11). The function of the operation switching means 46 of the microcomputer 41 stops the cooling operation if the operation state is during the cooling operation, and starts the operation by switching the operation state to the defrosting operation (step 12). On the other hand, when the operating state is the defrosting operation, the function of the operation switching means 46 continues the defrosting operation as it is (step 13). That is, the function of the first operation control means 49 of the microcomputer 41 is to operate the operation switching means 46 and the defrosting means 17 when the confinement alarm switch 5 is turned on by a person in the cabinet during the cooling operation. Switching to the defrosting operation, the defrosting operation is continued when the confinement alarm switch 5 is turned on during the defrosting operation. Thus, by performing the defrosting operation, the effect of increasing the internal temperature by the operation of the defrosting heater 14 can be expected.

Although the air around the unit cooler 3 in the cooling storage 1 is warmed by the start of the defrosting operation, the unit cooler 3 is usually installed at a position close to the ceiling in the cooling storage 1 so that it is trapped. It takes time to warm up to the air around the floor where people are. Therefore, the function of the fan control means 48 of the microcomputer 41 is to drive the evaporator fan 13 which is stopped during normal defrosting operation when the confinement alarm switch 5 is turned on by a person in the cooling storage 1. Is started (step 14). Thereby, the effect of warming the air per floor where the trapped person exists by circulating the warmed air in the cooling storage 1 more quickly can be expected.

FIG. 4 schematically shows the change in the internal temperature with time when this embodiment is implemented. As shown in FIG. 4A, when the microcomputer 41 detects that the confinement alarm switch 5 is pressed during the cooling operation, the defrosting operation is started, so that the temperature inside the chamber stops decreasing and rises. Begins. On the other hand, as shown in FIG. 4B, when the microcomputer 41 detects that the confinement alarm switch 5 is pressed during the defrosting operation, the internal temperature rises by continuing the defrosting operation. Continue.

The temperature in the cooling storage 1 can be raised by the defrosting operation and the operation of the evaporator fan 13. However, in the case of this heater defrosting system, the defrosting heater 14 itself becomes a high temperature exceeding 200 ° C. Therefore, when the defrost heater 14 is continuously energized for a long time, the internal temperature rises too much, and there is a possibility that a person trapped on the contrary is exposed to a high temperature environment for a long time. In general, the cooling storage 1 includes a thermistor 6 for measuring the internal temperature. Using this, the function of the second operation control means 50 of the microcomputer 41 is that the confinement alarm switch 5 is turned on, and the internal temperature detected by the thermistor 6 is set for the comfort of the person and When the temperature reaches an appropriate set temperature (for example, 25 ° C.) with respect to the storage stability of the object to be cooled, the operation of the refrigerant circuit 16 is stopped (steps 15 and 16). The operation stop here means that the defrosting operation is stopped and the operation of the evaporator fan 13 is also stopped. By controlling in this way, it is possible to prevent the internal temperature from rising excessively.

As described above, in the refrigeration apparatus of this embodiment, when it is detected that the confinement alarm switch 5 is operated, if the cooling operation is in progress, the frost removal operation is performed by switching to the defrosting operation. If so, it is configured to continue the defrosting operation as it is, so the temperature rise in the cooling storage 1 can be expected, and the risk that the trapped person will be exposed to the low temperature environment in the cooling storage for a long time is reduced. it can.

In addition, since the operation of the evaporator fan 13 that is stopped is started during the normal defrosting operation, the effect of warming the air around the floor where the confined person is present can be expected more quickly. The risk of being exposed to a low temperature environment for a long time can be reduced.

And, since the operation of the refrigerant circuit 16 is stopped when the internal temperature reaches an appropriate set temperature with respect to preset human comfort and preservability of the object to be cooled, On the other hand, it is possible to reduce the possibility that the trapped person is exposed to the low temperature environment in the cooling storage for a long time due to the excessive temperature rise.

Embodiment 2. FIG.
Next, a description will be given of a second embodiment that provides a refrigeration apparatus that prevents a person from being exposed to a low-temperature environment in a cooling storage for a long time and can also protect the state of the object to be cooled in the cooling storage 1 to some extent. To do. The figure which shows the structure of the freezing apparatus in Embodiment 2 is the same as what represented Embodiment 1, and is FIG. 1 and FIG.
FIG. 5 is a flowchart showing the control in the second embodiment of the present invention. The operation will be described according to this flowchart. In the control device 4 of the refrigeration apparatus according to this embodiment, the microcomputer 41 has the function of the third operation setting means 51. The function of the third operation setting means 51 is to stop the cooling operation and continue to drive the evaporator fan 13 when the confinement alarm switch 5 is turned on during the cooling operation. On the other hand, the function of the third operation setting means 51 is to stop the operation of the refrigerant circuit 16 when the confinement alarm switch 5 is turned on during the defrosting operation.

Specifically, when the function of the third operation setting means 51 of the microcomputer 41 detects that the confinement alarm switch 5 is operated during the operation of the refrigeration apparatus, the operation state is first confirmed (step 21), and the cooling operation is performed. If it is inside, the cooling operation is stopped. Incidentally, although the evaporator fan 13 is also stopped when the normal cooling operation is stopped, the operation of the evaporator fan 13 is continued here (step 22). By doing so, since the cooling operation is stopped, the temperature in the cooling storage 1 is not further reduced, but by circulating the air in the storage, temperature unevenness in the storage can be prevented, The cooling material can be protected from temperature rise to some extent.

On the other hand, if the defrosting operation is being performed based on the confirmation of the operation state (step 21), the operation of the refrigerant circuit 16 is stopped (step 23). Here, the evaporator fan 13 is already stopped during the defrosting operation. By doing in this way, it can prevent that the temperature in the cooling storage 1 raises further, and can protect a to-be-cooled object from temperature rise to some extent.

As described above, in the refrigeration apparatus according to the second embodiment, when it is detected that the confinement alarm switch 5 is operated, the operation of the evaporator fan 13 is continued while the cooling operation is stopped during the cooling operation. Since it is comprised in this way, the temperature rise and temperature nonuniformity in the cooling storage 1 can be suppressed. In addition, since the operation of the refrigerant circuit 16 is stopped during the defrosting operation, the temperature rise in the cooling storage 1 can be suppressed, and the stored object to be cooled can be more or less from the temperature rise. I can protect it. The control as shown in the second embodiment is a control that can be a particularly realistic choice when the temperature setting in the cooling storage 1 is relatively high.

In the above-described embodiment, the defrosting means 17 including the defrosting operation control means 47, the output means 44C, and the defrosting heater 14 is exemplified, but the defrosting means of the present invention is not limited thereto. For example, a four-way switching valve (not shown) for reversing the refrigerant flow direction of the refrigerant circuit 16 is newly provided in the refrigerant circuit 16, and the refrigerant flow path of the four-way switching valve is switched from the compressor 7 during the defrosting operation. It is also possible to make the defrosting means different from the defrosting means 17 by flowing the high-temperature and high-pressure refrigerant to the evaporator 12.

DESCRIPTION OF SYMBOLS 1 Cooling storage 2 Condensing unit 3 Unit cooler 4 Control device 5 Confinement alarm switch 6 Thermistor (inside temperature detector)
DESCRIPTION OF SYMBOLS 7 Compressor 8 Condenser 9 Condenser fan 10 Solenoid valve 11 Expansion valve 12 Evaporator 13 Evaporator fan 14 Defrost heater 15 Refrigerant piping 16 Refrigerant circuit 17 Defrost means 41 Microcomputer 45 Normal operation control means 46 Operation switching means 47 Defrosting operation control means 48 Fan control means 49 First operation control means 50 Second operation control means 51 Third operation control means

Claims

A cooling storage that is cooled by an evaporator installed in the storage;
A refrigerant circuit in which a compressor, a condenser, an expansion valve, and the evaporator are annularly connected in the described order;
An evaporator fan for blowing air in the cabinet to the evaporator;
A confinement alarm switch that is turned on by a person in the cooling storage;
Defrosting means for removing frost formation on the surface of the evaporator;
An operation switching means for switching between a cooling operation for cooling the inside of the cooling storage by the operation of the refrigerant circuit and a defrosting operation for removing frost on the surface of the evaporator by the operation of the defrosting means;
When the confinement alarm switch is turned on during the cooling operation, the operation switching means and the defrosting means are operated to switch to the defrosting operation, and the confinement alarm switch is turned on during the defrosting operation. First operation control means for continuing the defrosting operation when operated;
A refrigeration apparatus comprising:
The refrigeration apparatus according to claim 1, further comprising fan control means for driving the evaporator fan when the confinement alarm switch is turned on.
An internal temperature detector for detecting the internal temperature of the cooling storage;
A second operation control means for stopping the operation of the refrigerant circuit when the confinement alarm switch is turned on and the internal temperature detected by the internal temperature detector reaches a preset temperature;
The refrigeration apparatus according to claim 1 or 2, further comprising:
A cooling storage that is cooled by an evaporator installed in the storage;
A refrigerant circuit in which a compressor, a condenser, an expansion valve, and the evaporator are annularly connected in the described order;
An evaporator fan for blowing air in the cabinet to the evaporator;
A confinement alarm switch that is turned on by a person in the cooling storage;
Defrosting means for removing frost formation on the surface of the evaporator;
An operation switching means for switching between a cooling operation for cooling the inside of the cooling storage by the operation of the refrigerant circuit and a defrosting operation for removing frost on the surface of the evaporator by the operation of the defrosting means;
When the confinement alarm switch is turned on during the cooling operation, the cooling operation is stopped and the evaporator fan is continuously driven, and the confinement alarm switch is turned on during the defrosting operation. A third operation control means for stopping the operation of the refrigerant circuit in the case;
A refrigeration apparatus comprising: