JPH1038396A - Method of controlling freezer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an operation control method for a freezer capable of energy saving and uniform temperature control within a refrigerator, in the refrigerator equipped with a plurality of freezers. SOLUTION: A refrigerator has a plurality of freezers 8 equipped with condensing units 5 having compressors and condensers, coolers 6 having refrigerant decompressors and evaporators, and temperature sensors 6 for detecting the temperature within the refrigerator, belonging to the coolers 6. This is an operation control method which stops the freezers in order, starting with the one where the detection value of the temperature sensor 6 is lower, when reducing the number of operated units, by performing the control to reduce the number of operated freezers in stages when the temperature within the refrigerator falls down and the detection value of the temperature sensor 6 comes close to the set temperature within the refrigerator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the operation of a refrigerator when a plurality of refrigerators are installed in one refrigerator.

[0002]

2. Description of the Related Art Conventionally, as a method of controlling the capacity of a refrigerating apparatus in a refrigerator according to the load in a refrigerator, a condensing unit equipped with a plurality of compressors as described in Japanese Patent Application Laid-Open No. Hei 7-190508 is known. And there has been a method of controlling the capacity by increasing or decreasing the number of operating compressors according to the magnitude of the load.

However, when a plurality of refrigeration systems are installed in the same refrigerator, each refrigeration system can be operated or stopped only by a temperature sensor attached to each cooler, regardless of the other refrigeration systems. In particular, the control of capacity control was not performed.

[0004]

As described above, a refrigerator having a plurality of refrigeration units installed in the same refrigerator has a function that, when the temperature detected by a temperature sensor attached to each of the chillers reaches a set temperature, the refrigerator is individually operated. By merely stopping the refrigeration system, the number of operating units could not be controlled when the temperature in the refrigerator gradually approached the set value.

[0005] Therefore, all the refrigerating apparatuses are operated until the set value is reached, and all the refrigerating apparatuses are stopped when the set values are reached.

[0006] Further, since the temperature near the entrance of the refrigerator-freezer where people / goods enter / exit often increases due to the intrusion of outside air, the refrigeration system near the entrance / exit requires a longer operating time than other refrigeration systems, and therefore the refrigeration system near the entrance / exit. There is also a problem that the load on the compressor of the apparatus increases.

Accordingly, a first object of the present invention is to save energy and reduce storage by sequentially stopping a plurality of refrigerating devices when the temperature detected by a temperature sensor attached to a cooler approaches a set value. It is an object of the present invention to provide a method for controlling the operation of a refrigeration system that enables uniform temperature control of the inside of a refrigerator.

A second object of the present invention is to provide a method for controlling the operation of a refrigeration system in which the operation time of a plurality of refrigeration systems is controlled by rotation according to the operation time, thereby making the operation time uniform. .

[0009]

In order to achieve the first object, a first method for controlling operation of a refrigeration system according to the present invention comprises the steps of:
A plurality of refrigeration units including a compressor, a condensing unit having a condenser, a refrigerant decompression device, a cooler having an evaporator, and a temperature sensor attached to the cooler and detecting a temperature inside the refrigerator are provided in the same refrigerator. An operation control method when a table is installed, in which a reference temperature for stopping the refrigerating device in a stepwise manner in a temperature range higher than the set internal temperature is set in advance, and a temperature sensor attached to each cooler is set. Each time the detected temperature decreases and reaches a reference temperature at which the refrigerating apparatus is stopped, a part of the plurality of refrigerating apparatuses is sequentially stopped.

When a part of the plurality of refrigerating apparatuses is stopped at the reference temperature, it is preferable to stop the refrigerating apparatus that detects the lowest temperature among the temperature sensors attached to the individual coolers. Thereby, the temperature inside the refrigerator is made uniform.

Further, all the refrigeration systems are stopped when the set internal temperature is reached, and then, when the internal temperature rises to the operation resuming temperature, the refrigeration system stopped earlier earlier. It is better to start them sequentially from the device. This is effective in averaging the operation time of each refrigeration system.

In order to achieve the second object, a second operation control method for a refrigerating apparatus according to the present invention comprises a condensing unit, a cooler, An operation control method when a plurality of refrigeration units including a temperature sensor and an integrator for integrating the operation time of a compressor are installed in one refrigerator, and a temperature range higher than a set refrigerator temperature. A reference temperature at which the refrigerating apparatus is stopped in a stepwise manner is preset, and each time the detection value of the temperature sensor decreases and reaches the reference temperature, a part of the plurality of refrigerating apparatuses is sequentially stopped, and , The refrigeration system is sequentially stopped from the refrigeration unit in which the attached integrator shows a higher integrated value than the other integrators.

[0013] By controlling the rotation of the refrigerating apparatus based on the operating time of the compressor integrated in each refrigerating apparatus, the operating time of each refrigerating apparatus is made uniform.

Further, in the second operation control method of the refrigerating apparatus, when the set internal temperature is reached, all the refrigerating apparatuses are stopped, and then the internal temperature rises to reach the operation restart temperature. In this case, it is preferable to sequentially start the refrigerating apparatuses that have stopped earlier earlier.

Further, in order to achieve the second object,
The third operation control method for a refrigerating apparatus according to the present invention includes a plurality of refrigerating apparatuses including a condensing unit, a cooler, a temperature sensor, and an integrator, similarly to the operation control method for the second refrigerating apparatus. An operation control method when installed in one refrigerator, wherein two of a plurality of refrigerating devices are combined, at least one set of the combinations is provided, and a condensing unit is provided in each of the refrigerating devices. The operation time of each compressor is switched by connecting the condensing unit of one refrigerating device and the refrigerating device of the other refrigerating device via a switching valve. Is made uniform.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A refrigerating machine operation control method according to an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a configuration of a refrigerator according to a first embodiment of the present invention. The refrigerator 1 has a door 2 through which people and goods enter and exit,
Condensing unit 5 having compressor 3 and condenser 4
And a refrigerating device 8 which is connected to a pressure reducing device and a cooler 7 having an evaporator. In the refrigerating device 8, the refrigerant (gas) is compressed to a high temperature and a high pressure by the compressor 3, cooled and liquefied by a condenser, decompressed by a decompression device to a low temperature and a low pressure, and evaporated by an evaporator. At the time of this evaporation, the refrigerant takes away the heat of evaporation from the air in the refrigerator and cools this air. The evaporated refrigerant returns to the compressor 3.

Each refrigeration unit 8 has its own control unit 9
, And each control device 9 is controlled by one centralized controller 10.

Next, a method for controlling the operation of the refrigeration system will be described with reference to FIG. FIG. 2 shows the relationship between the temperature inside the refrigerator and the operation of sequentially stopping the operation of the plurality of refrigeration systems. In the figure, the horizontal axis represents the cooling operation time, and the vertical axis represents the internal temperature detected by the temperature sensor 6. Here, the target internal temperature is controlled by the central controller 10.
, The plurality of refrigeration units 8 are set in stages according to the set temperature (set temperature in the refrigerator) and the number of connected refrigeration units 8.
Are automatically determined, that is, the operation stop control values A and B (or more control values) for sequentially stopping the operation. The relationship between the number of refrigeration systems and the operation stop control value is experimentally obtained in advance.

The temperature detected by the temperature sensor 6 is sent to the centralized controller 10, and when the temperature drops to the control value A, some of the plurality of refrigeration units are stopped, and the temperature further drops, and the control value is lowered. By controlling the number of operating units such that several units stop when the number of units has decreased to B, energy saving can be achieved.

As a specific example of operation control, 6
When two refrigeration units are installed and the set temperature is set to -10 ° C., two control values of A = −6 ° C. and B = −8 ° C. are automatically set as the number of operating units control values, and Operation control is performed such that two units are stopped when the temperature reaches 6 ° C, and two more units are stopped when the temperature drops to -8 ° C. However, when the number of operating units is reduced and the internal temperature rises, the stopped refrigerating device is immediately restarted.

When reducing the number of operating refrigeration units,
By sequentially stopping the refrigerating devices having the lowest temperature detected by the individual temperature sensors, it is possible to reduce the unevenness of the temperature generated in the refrigerator and to make the temperature in the refrigerator uniform.

Each of the refrigeration units 8 is provided with a meter for measuring the operation time of the compressor, and the measured value is used as the operation time of the refrigeration units 8 to reduce the number of operating units. The operation times are accumulated by the centralized controller 10 and compared, and the stop order is controlled so that the operation times are uniform so that the respective operation times are uniform.

By controlling the rotation order of the refrigeration apparatus in this way, the operation time is made uniform, and the problem that only a specific refrigeration apparatus becomes longer in operation time is eliminated.

Further, after the temperature in the refrigerator has dropped to the thermo OFF value (set temperature in the refrigerator) and all the refrigerating devices have stopped,
The temperature inside the refrigerator rises again,
When the N value is reached, the refrigerating apparatuses that have been stopped earlier are sequentially started up earlier, and control is performed so that all the refrigerating apparatuses operate. When starting up sequentially, it is preferable to start up at a certain time interval.

As a result, the operating time can be made uniform, and an increase in the starting current caused by shifting the starting time can be suppressed.

FIG. 3 shows a unit configuration of a refrigeration apparatus according to a second embodiment of the present invention. This refrigerating apparatus unit includes two condensing units 5A and 5B having a compressor and a condenser, and two coolers 7A and 7B having a decompression device, an evaporator, and a temperature sensor for detecting a temperature in a refrigerator.
Is connected through two switching valves 13 and 14 with piping,
The combination of the condensing unit and the cooler can be switched. When the switching valves 13 and 14 operate in the directions shown by the solid lines, the condensing unit 5A and the cooler 7A are combined, and the condensing unit 5B and the cooler 7B are combined. On the other hand, when the switching valves 13 and 14 operate in the directions indicated by chain lines, the condensing unit 5A and the cooler 7B are combined, and the condensing unit 5B and the cooler 7A are combined.

As the operating time of each compressor is accumulated, the temperature inside the refrigerator near the refrigerator door increases due to the intrusion of outside air, so that the temperature detected by the temperature sensor also increases, and the operating time of the refrigeration system near the door increases. It will be long. Assuming that the cooler 7A of FIG. 3 is near the door, the cooler 7A
Before the switching valves 13 and 14 are switched, the condensing unit 5A is combined with the condensing unit 5A.
The operation time of A is longer than that of 5B. When the difference in the operation time exceeds a set time, the switching valves 13 and 14 are switched, and the condensing unit 5B and the cooler 7A, which have reduced the operation time, are combined to equalize the operation time of each condensing unit. Can be achieved.

Therefore, the operation time of only a certain refrigeration device out of the plurality of refrigeration devices becomes longer, and the problem of increasing the load on the compressor is eliminated.

In a refrigerator having three or more refrigerating devices, a combination of a condensing unit and a refrigerating device is used in a refrigerator having a relatively high cooling efficiency and a relatively low cooling efficiency. Appropriately provided refrigeration equipment
What is necessary is just to combine the required number of sets.

[0030]

As described above, according to the present invention,
When a plurality of refrigerating devices are installed in the same refrigerator, the number of operating units is controlled to be reduced stepwise in a temperature range close to the temperature set in the refrigerator, thereby saving energy and refrigerating with a lower detected temperature. By stopping the apparatus, uniform temperature control in the refrigerator becomes possible.

When the operation stop control is performed, the rotation is stopped in the order of the refrigeration units having the longest operation time, so that the operation time of each refrigeration unit can be made uniform, and the operation time of only a certain refrigeration unit can be reduced. The problem that the load becomes longer and the burden increases is also eliminated.

The operating time can also be made uniform by combining two refrigerating units and switching the combination of the condensing unit and the cooler.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a refrigerator-freezer according to an operation control method according to a first embodiment of the present invention.

FIG. 2 is a diagram showing operation control of controlling the number of operating refrigeration apparatuses of the present invention.

FIG. 3 is a cycle system diagram of a refrigeration apparatus according to an operation control method according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Refrigerator 2 Door 3 Compressor 4 Condenser 5 Condensing unit 6 Temperature sensor 7 Cooler 8 Refrigerator 9 Condensing unit / cooler controller 10 Centralized controller 11 Refrigerant piping 12 Electric wiring 13, 14 Switching valve

Claims (6)

[Claims] 1. A plurality of refrigerating apparatuses each comprising a condensing unit having a compressor and a condenser, a cooler having a refrigerant pressure reducing device and an evaporator, and a temperature sensor attached to the cooler and detecting a temperature in a refrigerator. In the operation control method of the refrigerating apparatus when installed in one refrigerator, a reference temperature at which the refrigerating apparatus is stopped stepwise in a temperature range higher than the set internal temperature is preset, and the detection value of the temperature sensor is set. A method of controlling the operation of a refrigerating apparatus, wherein a part of the plurality of refrigerating apparatuses is sequentially stopped each time the temperature of the refrigerating apparatus decreases to reach the reference temperature. 2. The refrigeration system according to claim 1, wherein when a part of the plurality of refrigeration systems is stopped at the reference temperature, the refrigeration system stops operation in order from a refrigeration system which detects a temperature lower than other temperature sensors. Operation control method. 3. When all of the refrigeration systems are stopped when the set temperature inside the refrigerator is reached, when the temperature inside the refrigerator rises again to reach the operation restart temperature, it is stopped earlier. 2. The operation control method for a refrigeration apparatus according to claim 1, wherein the operation is sequentially started from the refrigeration apparatus. 4. A condensing unit having a compressor and a condenser, a cooler having a refrigerant decompression device and an evaporator, a temperature sensor attached to the cooler and detecting a temperature in a refrigerator, and operation of the compressor. In a method for controlling operation of a refrigerating apparatus when a plurality of refrigerating apparatuses including an integrator for accumulating time are installed in one refrigerator, the refrigerating apparatuses are gradually stopped in a temperature range higher than a set internal temperature. A reference temperature is set in advance, and each time the detection value of the temperature sensor decreases and reaches the reference temperature, a part of the plurality of refrigerating devices is sequentially stopped, and when the part is stopped, an additional An operation control method for a refrigeration system, wherein the refrigeration system in which the integrators perform the operation is sequentially stopped from the refrigeration system having the higher integrated value than other integrators. 5. When all of the refrigeration systems are stopped when the set internal temperature is reached, when the internal temperature rises again to reach the operation restart temperature, the operation is stopped earlier. 5. The operation control method for a refrigeration apparatus according to claim 4, wherein the operation is sequentially started from the refrigeration apparatus. 6. A condensing unit having a compressor and a condenser, a cooler having a refrigerant decompression device and an evaporator, a temperature sensor attached to the cooler and detecting a temperature in a refrigerator, and operation of the compressor. In an operation control method of a refrigerating apparatus when a plurality of refrigerating apparatuses including an integrator that accumulates time are installed in one refrigerator, at least one combination of two of the plurality of refrigerating apparatuses is provided, In the combination, a switching valve is connected so as to connect the condensing unit and the cooler in each refrigeration unit, or to connect the condensing unit of one refrigeration unit and the cooler of the other refrigeration unit to each other. The operation control method of a refrigerating apparatus, characterized in that the operation times of the respective compressors are made uniform by switching over the compressor.