JPH10246549A - Operating method of showcase and controller therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effect predetermined cooling operation surely without any problem and without generating faulty defrosting even when a service interruption for a short period of time is generated by a method wherein the operation is re-started under an operating condition immediately before the service interruption, when is stored in a memory unit, upon restoration of power supply. SOLUTION: The condition of a power supply is monitored by a power supply detecting means 12 at all times during operation. When the power supply is in a normal state, the memory is renewed at all times and the newest operating condition is stored in an operating condition memory unit 13. When artificial power supply OFF due to maintenance and the like or the interception of the power supply due to service interruption, the operating condition upon the interception of the power supply is stored in the operating condition memory unit 13. When the power supply is returned to the normal condition of the same by the restoration of the putting ON of the power supply or the restoration of the service interruption, the power supply detecting means 12 detects it and an operating condition immediately before the interception of the power supply due to the putting OFF of the power supply or the service interruption, which are stored in the operating condition memory unit 13, is decided and the operation is re-started under the operating condition immediately before the interception of the power supply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a showcase operating method and control device, and more particularly, to a showcase operating method and a control device thereof when a power supply cutoff occurs in a showcase in which a plurality of coolers are alternately defrosted. It is related to the configuration of

[0002]

2. Description of the Related Art As shown in FIG.
The showcase 1 provided with B suppresses temperature fluctuations in the showcase (inside the refrigerator) by alternately performing the defrosting operation of the coolers A and B, and performs efficient defrosting using the properties of the refrigerant. The frost operation can be performed. Such 2
As a countermeasure at the time of power interruption in the showcase 1 provided with the system coolers A and B, for example, Japanese Patent Publication No. 7-186
As described in Japanese Patent Publication No. 01, when the operation state immediately before the power shutoff is the cooling operation, the cooling operation is restarted when the power is restored, and when the defrosting operation is performed, the pump down for collecting the refrigerant in the cooler is performed. A method of resuming driving from driving is known.

[0003]

However, the above-mentioned method has no problem when the power is cut off for a relatively long time, but the current power outage in Japan is a short-time power outage such as an instantaneous power outage of 1 second or less. In most cases, power outages over a long period of time are extremely small. Therefore, when a short-time power failure occurs during the defrosting operation, when the operation is resumed from the pump-down operation as described above, the defrost of the cooler is not sufficiently performed and the pump-down operation is performed. Because it shifts, there is a possibility that poor defrosting of the cooler will occur,
There is a possibility that the temperature inside the refrigerator may be increased by affecting the next cooling operation.

Accordingly, the present invention provides a method of controlling a showcase and a control method for the showcase which can reliably perform a predetermined cooling operation without causing a problem of defrosting even when a short-time power failure occurs. It is intended to provide a device.

[0005]

To achieve the above object, a showcase operating method according to the present invention comprises a plurality of coolers and alternately performs a defrosting operation of each cooler. In the above, the state of the power supply is detected by the power supply detecting means, and the operation state at the time of power supply interruption is stored in the storage unit based on the detection signal. It is characterized by restarting the operation in the state.

According to the above configuration, if a short-time power interruption occurs during the defrosting operation, the operation is restarted from the defrosting operation when the power is restored, so that a sufficient defrosting operation can be performed. In addition, it is possible to prevent poor defrosting of the cooler. Further, during the cooling operation, since the cooling operation is restarted, there is no occurrence of cooling failure due to the cooling operation time being completed in a short time. It should be noted that there is no problem during the pump down operation because the operation is restarted from the pump down operation.

On the other hand, when the power supply is cut off for a long time, the compressor and the solenoid valve of the refrigerator do not operate due to the power supply cutoff, and an off-cycle state is set, so that the cooler is naturally defrosted. . In this case, even when the power is cut off and the operation is restarted from the cooling operation, the predetermined cooling operation can be performed because the cooler is in a defrosted state. In addition, when the power supply shuts down during the defrosting operation, the operation is restarted from the defrosting operation. Thus, the cooling operation can be restarted, and the inside of the refrigerator can be cooled to a predetermined temperature.

Further, the showcase control device of the present invention comprises a plurality of coolers, and in a showcase control device which alternately performs a defrosting operation of each cooler, a power supply detecting means for detecting a power supply state. An operation state storage unit that stores an operation state at the time of power supply interruption based on a detection signal from the power supply detection unit, and outputs an operation state immediately before the power supply interruption when the power supply is restored after the power supply interruption occurs. Features.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing a main part of a control device for a showcase of the present invention. FIG. 2 is a flowchart showing an example of an operation procedure of the method of the present invention.
5 is a flowchart illustrating another function of the control unit of the apparatus of the present invention.

First, as shown in FIG. 1, the control device of the present invention is applied to a showcase having a plurality of, for example, two systems of coolers A and B, as in the showcase 1 shown in FIG. The control unit 11 includes a normal control unit (not shown), for example, a control unit that performs temperature control and defrost control.
A power supply detecting means 12 for detecting a state of a power supply, and based on a detection signal from the power supply detecting means 12, an operation state at the time of power supply interruption is stored. Output operating state storage unit 13
And an elapsed time measuring unit 14 for measuring an elapsed time from the previous defrosting operation, an elapsed time setting unit 15 for setting an allowable elapsed time since the previous defrosting operation, and an elapsed time measuring unit 14. When a predetermined defrosting operation is not performed even when the elapsed time of the elapsed time timer 14 reaches the elapsed allowable time of the elapsed time setting unit 15 by comparing the elapsed time with the allowable elapsed time of the elapsed time setting unit 15 The control unit 11 is provided with a comparison operation unit 16 which sends out a signal for defrosting all the coolers by stopping the supply of the refrigerant to all the coolers provided in the showcase. Have been.

By forming the control device of the showcase as described above, when the power supply is cut off, the elapsed time from the previous defrosting operation is less than the allowable elapsed time set in the elapsed time setting unit 15. If not, the operation is restarted in the operation state at the time of power-off stored in the operation state storage unit 13. Further, when the defrosting operation is not performed even if the elapsed time from the previous defrosting operation reaches the permissible time set in the elapsed time setting unit 15, that is, the predetermined defrosting operation is performed for some reason. If not, or if the power cutoff time is long, the supply of the refrigerant to all the coolers is stopped, and the operation is restarted in an operation state in which the defrost of all the coolers is forcibly performed.

FIG. 2 shows an example of a flowchart for carrying out the method of the present invention. First, step 2
The line from 1 to step 26 shows the flow of the normal operation state.
A normal cooling operation using a system cooler is performed. At this time, the control unit 11 outputs a temperature control output according to a change in the internal temperature and the like detected by various temperature sensors.

Next, in step 22, a defrosting operation A for defrosting one of the coolers is performed according to a preset defrosting start condition. The defrosting operation A is performed for a predetermined time or until the temperature of the cooler portion rises to a predetermined temperature by supplying the high-pressure refrigerant to the cooler that performs the defrosting operation.
Subsequently, in step 23, a refrigerant recovery operation (pump-down operation) A for recovering the high-pressure refrigerant in the cooler is performed,
Preparation for the cooling operation of the cooler is performed.

When the defrosting of one of the coolers is completed as described above, the cooling operation by the two coolers is started again in step 24, and the same control as in step 21 is performed.
Next, in step 25, a defrosting operation B for defrosting the other cooler is performed, and subsequently, in step 26, a refrigerant recovery operation B for this cooler is performed, and then the first operation state, step 21 is performed. Return to

During the operation of steps 21 to 26, the state of the power supply is constantly monitored by the power supply detecting means 12. When the power supply is in a normal state, the memory is always updated, and the latest operation is performed. The state is stored in the operation state storage unit 13. If the power supply is turned off due to an artificial power OFF or power failure due to maintenance or the like, the operation proceeds to step 27 in any of the operation states of steps 21 to 26, and the operation state at the time of power supply interruption is stored in the operation state storage. It is stored and held in the unit 13.

When the power supply returns to a normal state due to power-on or recovery from a power failure, the power supply detecting means 12 detects this in step 28, and in step 29, the power-off and power failure stored in the operation state storage unit 13 causes The operation state immediately before the power cutoff is determined, and the process returns to any one of the steps 21 to 26 to resume the operation in the operation state immediately before the power cutoff.

Thus, if the cooling operation has been performed, the state of the cooling operation (step 21 or step 2)
Since the operation is restarted in 4), a predetermined cooling operation can be performed without increasing the temperature in the refrigerator. Further, when either of the defrosting operations A and B has been performed (step 22 or step 25), the defrosting operation is restarted.
After the defrost of the cooler is sufficiently performed, the process proceeds to the next refrigerant recovery operation (Step 23 or Step 26).

Therefore, when the power supply shuts down immediately after the start of the defrosting operations A and B and the power supply is recovered in a short time (recovery from power failure), the predetermined defrosting operation can be continued. Thus, sufficient defrosting can be performed in the same manner as in the normal case. Accordingly, the refrigerant recovery operation is performed while the defrosting is insufficient, and the cooling operation is started. The cooling operation is prevented from being affected by the frost remaining in the cooler, and the predetermined cooling operation can be performed.

FIG. 3 is a flowchart for explaining other functions of the control device having the configuration shown in FIG. Step 21 to Step 2 in this flowchart
6 is the same as the flowchart shown in FIG.
Step 21 is a cooling operation, Step 22 is a defrosting operation A,
Step 23 is a refrigerant recovery operation A, step 24 is a cooling operation again, step 25 is a defrost operation B, and step 26 is a refrigerant recovery operation B, which is a loop during normal operation.

In this flowchart, in parallel with the cooling operation in step 21 and the cooling operation in step 24, the elapsed time from the previous defrosting operation measured by the elapsed time timer 14 and the elapsed time Steps 31 and 32 are provided for comparing the elapsed allowable time set in the setting unit 15 with the comparison calculation unit 16, respectively. In addition to the steps 31 and 32, the forced elimination for stopping the supply of the refrigerant to the cooler is performed. Steps 33 and 34 for performing frost are provided,
Further, the elapsed time measured by the elapsed time timer 14 is reset after the steps 33 and 34, after the defrosting operation A at the step 22 and after the defrosting operation B at the step 25. Steps 35, 36, 37 and 38 are provided. Therefore, when the normal operation state is being performed, the next step 35 or step 3 is performed after the completion of the defrosting operation in step 22 or 25.
In step 6, the elapsed time is reset, and the normal operation loop from step 21 to step 26 is continued.

That is, during the cooling operation in step 21 or step 24, the elapsed time from the previous defrosting operation and the allowed permissible time are constantly compared in step 31 or step 32. If the elapsed time from the time has not reached the permissible elapsed time, step 2
Returning to the cooling operation of 1 or step 24, the cooling operation is continued for a predetermined time. On the other hand, the cooling operation in step 21 or step 24 is continued for a long time for some reason, and the process does not proceed to the defrosting operation A in step 22 or the defrosting operation B in step 25. If it is determined that the elapsed time since the defrosting operation has reached the permissible elapsed time,
Proceeding to step 33 or step 34, the defrosting of all the coolers is forcibly performed by performing the forced defrost for stopping the supply of the refrigerant to all the coolers.

Thus, it is possible to prevent the cooling operation from being continued for a long time for some reason, thereby increasing the amount of frost formed on the cooler and causing a cooling failure. This forced defrosting is terminated by a normal defrosting operation such as a method in which a temperature sensor detects a temperature of a cooler portion or a cool air temperature in a cool air blowing section and terminates when the detected temperature is equal to or higher than a predetermined temperature. It can be terminated in the same way as the procedure.

When the forced defrost in step 33 or step 34 is completed, step 37 or step 38
After resetting the elapsed time of the elapsed time counting unit 14, the process returns to the cooling operation in step 21 or 24, and returns to the loop for performing the normal operation procedure. If a relatively long power interruption occurs and the power interruption time exceeds the above-mentioned abnormal allowable time period, steps 33 and 3 are executed.
Although the forced defrosting of 4 is performed, if the defrosting of the cooler is sufficiently performed while the power is shut off as described above, the process returns to the predetermined cooling operation immediately after step 37 or step 38. Thus, the inside of the refrigerator can be cooled to a predetermined temperature in a short time.

The permissible elapsed time set in the elapsed time setting section 15 is determined by taking into account the defrost timing in the normal operation state and the time when there is no problem in restarting the cooling operation at the time of power-off recovery. It can be set appropriately according to the operating temperature of the showcase.

[0025]

As described above, according to the showcase operating method and control device of the present invention, the operation can be efficiently restarted after the power is cut off due to a power failure or the like, and the defrosting is insufficient. There is no occurrence of poor cooling or the like due to the above.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main part of a control device for a showcase of the present invention.

FIG. 2 is a flowchart showing an example of an operation procedure of the method of the present invention.

FIG. 3 is a flowchart illustrating another function of the control device.

FIG. 4 is a schematic sectional view of a showcase provided with two systems of coolers.

[Explanation of symbols]

 A, B cooler 1 showcase 11 control unit 12 elapsed time counting unit 13 elapsed time setting unit 14 comparison operation unit 15 power supply detection means 16 operation state storage unit

Claims (2)

[Claims] 1. A showcase operating method comprising a plurality of coolers and alternately performing a defrosting operation of each cooler, wherein a power supply state is detected, and based on the detection signal, an operation state at the time of power supply cutoff is detected. A showcase operation method, wherein the operation is restarted in an operation state immediately before the power is turned off when the power is restored. 2. A control device for a showcase comprising a plurality of coolers and alternately performing a defrosting operation of each cooler, wherein a power supply detecting means for detecting a power supply state, and a detection signal from the power supply detecting means. Memorize the operation state at the time of power off based on
A control unit for a showcase, comprising: an operation state storage unit that outputs an operation state immediately before the power supply is cut off when the power supply is restored after the power supply is cut off.