JP6359336B2 - Cooling device and heating device - Google Patents

Description

  The present invention relates to a technique for cooling or heating the inside of a refrigerator.

  Conventionally, the temperature control of the open showcase that starts the operation of the cooler when the temperature detected by the temperature sensor that detects the temperature inside the chamber rises to the cooling start temperature, and stops the cooler when it falls to the cooling stop temperature. The device is known. In such an internal temperature control device, in order to maintain an appropriate internal temperature with little influence of the outside air temperature, when the outside air temperature detected by the outside air temperature sensor does not match the standard outside air temperature, cooling starts. A technique for correcting the temperature and the cooling stop temperature is known (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 06-180174

  However, according to the conventional technology described above, there is a problem that the configuration of the apparatus becomes complicated because it is necessary to provide an outside air temperature sensor in addition to the temperature sensor for detecting the temperature in the warehouse.

  In this specification, when the internal temperature rises to the cooling start temperature, the operation of the cooler is started, and when the internal temperature decreases to the cooling suppression temperature, the ambient temperature is detected in the cooling device that suppresses the operation of the cooler. Disclosed is a technique for reducing the difference between the inside average temperature and the inside set temperature without providing an outside air temperature sensor.

  Further, in this specification, in the heating device that starts the operation of the heater when the internal temperature decreases to the heating start temperature and suppresses the operation of the heater when the internal temperature increases to the heating suppression temperature, the ambient temperature is Disclosed is a technique for reducing the deviation between the inside average temperature and the inside set temperature without providing an outside temperature sensor to detect.

  The cooling device disclosed by this specification is provided with the cooler which cools the inside of a store | warehouse | chamber, the internal temperature sensor which detects the internal temperature, and a control part, The said control part is based on the said internal temperature sensor. The detected internal temperature is monitored, and when the internal temperature rises to the cooling start temperature, the operation of the cooler is started, and when the internal temperature decreases to the cooling suppression temperature lower than the cooling start temperature, A control process for suppressing operation and a change process for changing at least one of the cooling start temperature and the cooling suppression temperature based on the operating rate of the cooler are executed.

  If the temperature around the cooling device is high, the internal temperature is difficult to decrease, and the operating rate of the cooler increases. On the other hand, if the temperature around the cooling device is low, the internal temperature tends to decrease, so the operating rate of the cooler decreases. Thus, the operating rate of the cooler has a correlation with the temperature around the cooling device. According to the cooling device, since at least one of the cooling start temperature and the cooling suppression temperature is changed based on the operation rate of the cooler, the inside average temperature without the outside temperature sensor for detecting the ambient temperature of the cooling device and Deviation from the set temperature in the cabinet can be reduced.

  Moreover, the said control part may make the said cooling suppression temperature high when the operation rate of the said cooler becomes more than a reference | standard operation rate in the said change process.

  According to the cooling device, since the cooling suppression temperature is increased when the operating rate of the cooler is equal to or higher than the reference operating rate, the internal average temperature and the internal set temperature are not provided with an outside air temperature sensor that detects the ambient temperature. Deviation can be reduced.

  Moreover, the cooling device disclosed by this specification is equipped with the cooler which cools the inside of a store | warehouse | chamber, the interior temperature sensor which detects the interior temperature, and a control part, The said control part is the said interior temperature. The internal temperature detected by the sensor is monitored, and when the internal temperature rises to the cooling start temperature, the operation of the cooler is started. When the internal temperature decreases to the cooling suppression temperature lower than the cooling start temperature, the cooling is started. At least one of the cooling start temperature and the cooling suppression temperature is changed based on a control process that suppresses the operation of the machine and a difference between the average value of the internal temperature detected by the internal temperature sensor and the internal set temperature. Change processing to be executed.

  According to the cooling device, since at least one of the cooling start temperature and the cooling suppression temperature is changed based on the difference between the average value of the inside temperature and the set temperature in the inside, the outside air temperature sensor that detects the ambient temperature is provided. In addition, the difference between the inside temperature and the set temperature can be reduced.

  Further, in the change process, the control unit may increase the cooling suppression temperature when an average value of the internal temperature detected by the internal temperature sensor is lower than a reference value with respect to the internal set temperature. Good.

  According to the above cooling device, since the cooling suppression temperature is increased when the average value of the internal temperature detected by the internal temperature sensor becomes lower than the reference value with respect to the internal set temperature, the outside temperature sensor detects the ambient temperature. It is possible to reduce the divergence between the average temperature inside the cabinet and the set temperature inside the cabinet without providing.

  Moreover, the cooling device disclosed by this specification is equipped with the cooler which cools the inside of a store | warehouse | chamber, the interior temperature sensor which detects the interior temperature, and a control part, The said control part is the said interior temperature. The internal temperature detected by the sensor is monitored, and when the internal temperature rises to the cooling start temperature, the operation of the cooler is started. When the internal temperature decreases to the cooling suppression temperature lower than the cooling start temperature, the cooling is started. Based on the control process for suppressing the operation of the machine, the change width of the operating rate of the cooler, and the difference between the average value of the internal temperature detected by the internal temperature sensor and the internal set temperature, And a change process for changing at least one of the cooling start temperature and the cooling suppression temperature.

  According to the above cooling device, the cooling start temperature and the cooling suppression temperature are based on the range of change of the operating rate of the cooler and the difference between the average value of the internal temperature detected by the internal temperature sensor and the internal set temperature. Therefore, it is possible to accurately determine whether or not to change the cooling start temperature or the cooling suppression temperature while suppressing the unstable operation of the cooler.

  Further, in the change process, the control unit has a change width of the operating rate of the cooler that is equal to or larger than a first reference value, and an average value of the internal temperature detected by the internal temperature sensor is When the temperature is lower than the second reference value by the internal set temperature, the cooling suppression temperature may be increased.

  According to the cooling device, the change width of the operating rate of the cooler is equal to or greater than the first reference value, and the average value of the internal temperature detected by the internal temperature sensor is the second relative to the internal set temperature. Since the cooling suppression temperature is increased when the reference value is lower than the reference value, it is possible to accurately determine whether or not to change the cooling suppression temperature while suppressing the unstable operation of the cooler.

  Moreover, the said control part WHEREIN: In the said change process, the said cooling start temperature after a change or the said cooling suppression temperature after a change is the average value of the internal temperature detected by the said internal temperature sensor, and the said internal setting temperature It may be determined on the basis of the difference.

  According to the above cooling device, there is a possibility that the difference between the average value of the internal temperature and the internal set temperature can be reduced compared to the case where the cooling suppression temperature and the cooling start temperature after the change are fixedly determined. Get higher.

  Moreover, the heating apparatus disclosed by this specification is equipped with the heating machine which heats the inside of a store | warehouse | chamber, the interior temperature sensor which detects the interior temperature, and a control part, The said control part is the said interior temperature. The internal temperature detected by the sensor is monitored, and the operation of the heater is started when the internal temperature decreases to the heating start temperature, and when the internal temperature rises to a heating suppression temperature higher than the heating start temperature, the heating is started. A control process that suppresses the operation of the machine and a change process that changes at least one of the heating start temperature and the heating suppression temperature based on the operating rate of the heater.

  According to the heating device, since at least one of the heating start temperature and the heating suppression temperature is changed based on the operating rate of the heater, the inside average temperature and the inside setting are provided without an outside temperature sensor that detects the ambient temperature. Deviation from temperature can be reduced.

  Moreover, the heating apparatus disclosed by this specification is equipped with the heating machine which heats the inside of a store | warehouse | chamber, the interior temperature sensor which detects the interior temperature, and a control part, The said control part is the said interior temperature. The internal temperature detected by the sensor is monitored, and the operation of the heater is started when the internal temperature decreases to the heating start temperature, and when the internal temperature rises to a heating suppression temperature higher than the heating start temperature, the heating is started. At least one of the heating start temperature and the heating suppression temperature is changed based on a control process that suppresses the operation of the machine and a difference between the average value of the internal temperature detected by the internal temperature sensor and the internal set temperature. Change processing to be executed.

  According to the above heating device, since at least one of the heating start temperature and the heating suppression temperature is changed based on the difference between the average value of the internal temperature and the set temperature in the internal storage, an outside air temperature sensor that detects the ambient temperature is provided. In addition, the difference between the inside temperature and the set temperature can be reduced.

  Moreover, the heating apparatus disclosed by this specification is equipped with the heating machine which heats the inside of a store | warehouse | chamber, the interior temperature sensor which detects the interior temperature, and a control part, The said control part is the said interior temperature. The internal temperature detected by the sensor is monitored, and the operation of the heater is started when the internal temperature decreases to the heating start temperature, and when the internal temperature rises to a heating suppression temperature higher than the heating start temperature, the heating is started. Based on the control process for suppressing the operation of the machine, the change width of the operating rate of the heater, and the difference between the average value of the internal temperature detected by the internal temperature sensor and the internal set temperature, And a change process for changing at least one of the heating start temperature and the heating suppression temperature.

  According to the above heating device, the heating start temperature and the heating suppression temperature are changed based on the change width of the operating rate of the heater and the difference between the average value of the internal temperature detected by the internal temperature sensor and the internal set temperature. Since at least one of them is changed, it is possible to accurately determine whether or not to change the heating start temperature and the heating suppression temperature while suppressing the unstable operation of the heater.

  According to the above cooling device, in the cooling device that starts the operation of the cooler when the internal temperature rises to the cooling start temperature and suppresses the operation of the cooler when the internal temperature decreases to the cooling suppression temperature, the ambient temperature is reduced. The divergence between the inside average temperature and the inside set temperature can be reduced without providing the outside temperature sensor to be detected.

  Further, according to the above heating device, in the heating device that starts the operation of the heater when the internal temperature decreases to the heating start temperature and suppresses the operation of the heater when the internal temperature rises to the heating suppression temperature, The difference between the inside average temperature and the inside set temperature can be reduced without providing an outside temperature sensor for detecting the temperature.

FIG. 3 is a cross-sectional view of the open showcase according to the first embodiment. The block diagram which shows the electrical constitution of an open showcase. The graph which shows the change of the internal temperature in a normal environment. The graph which shows the change of the internal temperature in case the cooling suppression temperature is not made high in a severe environment. The graph which shows the change of the temperature in a store | warehouse | chamber when the cooling suppression temperature is made high in a severe environment. The schematic diagram for demonstrating a cooling suppression temperature change process. The graph which shows the chamber internal temperature in 1 cycle in the normal environment which concerns on Embodiment 2. FIG. The graph which shows the internal temperature in 1 cycle in a severe environment. The schematic diagram for demonstrating the cooling suppression temperature change process which concerns on Embodiment 3. FIG.

<Embodiment 1>
The first embodiment will be described with reference to FIGS.
(1) Configuration of Open Showcase First, the configuration of an open showcase 1 as a cooling device according to Embodiment 1 will be described with reference to FIG. In the following description, it is assumed that the left side in FIG. 1 is the front side of the open showcase 1 and the right side is the rear side.

  The open showcase 1 includes a main body portion 11 that constitutes a refrigerator 10 that is open on the front side, and a machine room 12 that is provided below the main body portion 11. An inside bottom plate 13, a back panel 14, and an inside top plate 15 are provided inside the main body 11. A circulation ventilation path 16 is formed by these plates and panels and the main body 11. A plurality of shelves 17 for displaying products are attached to the front side of the back panel 14 so as to be spaced apart in the vertical direction.

  An internal fan 18, an evaporator 19, and an internal temperature sensor 20 are provided between the bottom surface of the main body 11 and the internal bottom plate 13. As shown in FIG. 1, the internal temperature sensor 20 is provided between the internal fan 18 and the evaporator 19.

  A suction port 21 is provided on the front side of the inner bottom plate 13 for sucking the air in the warehouse into the circulation ventilation path 16. Further, an air outlet 22 is provided on the front side of the internal upper plate 15 to blow out the air in the circulation ventilation path 16 into the internal space. When the internal fan 18 rotates, the internal air is sucked into the circulation ventilation path 16 from the suction port 21. The sucked air is cooled by the evaporator 19 and blown out from the outlet 22 into the cabinet.

  As shown in FIG. 1, the air outlet 22 is provided so as to blow air toward the suction port 21, and an air curtain is formed by the air blown from the air outlet 22 toward the suction port 21. Further, the back panel 14 is provided with a plurality of holes (not shown), and the air flowing through the circulation ventilation path 16 also flows into the cabinet through the holes.

  The machine room 12 is provided with a compressor 23, a condenser 25, a capillary tube 24 that connects the condenser 25 and the evaporator 19, a condenser fan 26 that cools the condenser 25, and the like. The compressor 23, the condenser 25, the capillary tube 24, the evaporator 19, and the condenser fan 26 constitute a cooler.

(2) Electrical configuration of the open showcase Next, the electrical configuration of the open showcase 1 will be described with reference to FIG. The open showcase 1 includes a control unit 30. The compressor 30, the internal fan 18, the internal temperature sensor 20, and the condenser fan 26 described above are electrically connected to the control unit 30.

  The control unit 30 includes a CPU 31, a ROM 32, a RAM 33, and the like. The CPU 31 controls each part of the open showcase 1 by executing a control program stored in the ROM 32. The ROM 32 stores a control program executed by the control unit 30 and various data used for control. The RAM 33 is used as a main storage device for the CPU 31 to execute various processes.

(3) Temperature Control Process Next, the temperature control process executed by the control unit 30 will be described with reference to FIG. The temperature control process is an example of a control process. Here, the standard temperature of the environment where the open showcase 1 is installed is assumed in advance. In the example shown in FIG. 3, the temperature of the environment in which the open showcase 1 is installed is assumed to be the standard temperature described above or the surrounding temperature. In the following description, the standard temperature described above or the surrounding temperature is referred to as a normal temperature, and an environment where the ambient temperature of the open showcase 1 is a normal temperature is referred to as a normal environment.

  The controller 30 monitors the internal temperature detected by the internal temperature sensor 20, and starts the operation of the compressor 23 when the internal temperature rises to a preset cooling start temperature. When the operation of the compressor 23 is started, the internal temperature gradually decreases. The controller 30 stops the operation of the compressor 23 when the internal temperature drops to the cooling suppression temperature lower than the cooling start temperature. When the operation of the compressor 23 is stopped, the internal temperature gradually rises. By repeating this, the internal temperature is maintained between the cooling start temperature and the cooling suppression temperature.

  Here, starting the operation of the compressor 23 is an example of starting the operation of the cooler. Moreover, stopping the operation of the compressor 23 is an example of suppressing the operation of the cooler. In addition, you may suppress the driving | operation of the compressor 23 by reducing the cooling effect rather than stopping the driving | operation of the compressor 23 completely.

  The above-described cooling start temperature and cooling suppression temperature are determined in advance by experiments or the like so that the average value of the internal temperature (hereinafter referred to as “internal average temperature”) and the internal set temperature in the normal environment substantially coincide with each other. It is. For this reason, in the case of a normal environment, by performing the above-described temperature control process, the inside temperature in the box and the set temperature in the box almost coincide as shown in FIG. That is, in the normal environment, the difference between the inside average temperature and the inside set temperature is small.

(4) Change of cooling suppression temperature Next, with reference to FIG. 4, the temperature change at the time of performing the temperature control process mentioned above in the environment where the ambient temperature of the open showcase 1 is higher than the normal temperature mentioned above is demonstrated. . In the following description, an environment in which the temperature around the open showcase 1 is higher than the normal temperature is referred to as a severe environment.

  As shown in FIG. 4, in a severe environment, the internal temperature is difficult to decrease due to the high ambient temperature. For this reason, in a severe environment, it takes a long time for the internal temperature to drop to the cooling suppression temperature after the operation of the compressor 23 is started. However, since the ambient temperature is high in a harsh environment, the time from when the operation of the compressor 23 is stopped until the internal temperature reaches the cooling start temperature is largely different from that in the normal environment (in the case shown in FIG. 3). Absent.

That is, the operating time of the compressor 23 is longer than that of the normal environment in a harsh environment, but the operation time of the compressor 23 is higher than that of the normal environment because the stop time of the compressor 23 is not significantly different from that of the normal environment. . Here, it is assumed that the operating rate is expressed by the following formula 1.
Operation rate = Operation time / (Operation time + Stop time) ・ ・ ・ Equation 1

  When the operation rate of the compressor 23 is high, the average temperature inside the compartment is lower than the preset temperature inside the compartment as shown in FIG. That is, when the operation rate of the compressor 23 is high, the difference between the internal temperature and the internal set temperature becomes large. Therefore, the control unit 30 changes at least one of the cooling start temperature and the cooling suppression temperature based on the operating rate of the compressor 23 in order to reduce the difference between the internal average temperature and the internal set temperature. Specifically, the control unit 30 according to the first embodiment increases the cooling suppression temperature when the operation rate of the compressor 23 increases.

  With reference to FIG. 5, the change in the internal temperature when the cooling suppression temperature is increased will be described. As shown in FIG. 5, when the cooling suppression temperature is increased, the internal temperature decreases to the cooling suppression temperature at a point earlier than when the cooling suppression temperature is not increased (in the case illustrated in FIG. 4). When the internal temperature is lowered to the cooling suppression temperature at an early point, the operation time of the compressor 23 is shortened, so that the operation rate of the compressor 23 is lowered. Thereby, compared with the case where a cooling suppression temperature is not made high, the deviation between the inside average temperature and the inside set temperature can be reduced.

  Here, in the first embodiment, the changed cooling suppression temperature is fixed and determined in advance. The cooling suppression temperature after the change can be determined as appropriate, but if it is too high, the average temperature in the cabinet may greatly exceed the preset temperature in the cabinet. It is desirable that the temperature be such that the difference between the inner average temperature and the set temperature in the cabinet is small.

  Next, the cooling suppression temperature changing process executed by the control unit 30 will be described with reference to FIG. The cooling suppression temperature changing process is an example of a changing process. In the following description, operating the compressor 23 in a normal environment is referred to as normal operation, and operating the compressor 23 in a severe environment is referred to as severe operation.

  Every time a predetermined time such as 1 second elapses, the control unit 30 starts from that time, and a reference operation in which the operation rate of the compressor 23 in the past fixed time (Ta time in the figure) is set in advance. It is judged whether or not it is higher than the rate. And the control part 30 raises cooling suppression temperature, when an operation rate is more than a reference | standard operation rate.

  For example, the time T1 includes a period in which the compressor 23 is severely operated within the past Ta time from that time (time T1), but includes a period in which the compressor 23 is normally operated. Then, it is assumed that the operation rate of the compressor 23 in the past Ta time has not yet exceeded the reference operation rate. For this reason, the control unit 30 does not yet increase the cooling suppression temperature at the time point T1.

  Then, it is assumed that the operation rate in the past Ta time becomes equal to or higher than the reference operation rate for the first time at time T2. In this case, the control unit 30 increases the cooling suppression temperature at time T2. As described above, since the operation time of the compressor 23 is shortened when the cooling suppression temperature is increased, the operation time of the compressor 23 is shortened in the severe operation after the time point T2 as compared with the severe operation before the time point T2.

  By the way, if the cooling suppression temperature is kept high, the operating rate of the compressor 23 is reduced when the surrounding environment returns to the normal environment, and the average temperature in the storage greatly exceeds the set temperature in the storage. There is a fear. For this reason, when the operation rate of the compressor 23 becomes less than the reference operation rate, it is desirable to return the cooling suppression temperature to the original.

(5) Effects of the embodiment According to the open showcase 1 according to the first embodiment described above, the cooling suppression temperature is increased when the operation rate of the compressor 23 is equal to or higher than the reference operation rate, so that the outside air that detects the ambient temperature is detected. A deviation between the inside average temperature and the inside set temperature can be reduced without providing a temperature sensor.

  Also, when an outside temperature sensor that detects the ambient temperature is used, the intended effect cannot be obtained under conditions in which the temperature changes locally only around the outside temperature sensor, and there is a risk that the effect may be adversely affected. is there. On the other hand, according to the open showcase 1, since the outside temperature sensor is not used, the intended effect can be obtained more reliably.

  Further, when the cooling suppression temperature is increased, the time for operating the evaporator 19 at a low temperature is shortened. Therefore, in the case of a cooling device that is easily frosted like the open showcase 1, it is also effective in suppressing frosting. Moreover, since it is necessary to stop the compressor 23 in the defrost operation which melt | dissolves the frost adhering to the evaporator 19, it is easy to raise the internal temperature. As described above, when the cooling suppression temperature is increased, frosting is suppressed, so that the number of defrosting operations can be suppressed. Thereby, it can also suppress that the internal temperature rises by defrost operation.

<Embodiment 2>
Next, a second embodiment will be described with reference to FIGS.
The control unit 30 according to the first embodiment described above changes at least one of the cooling start temperature and the cooling suppression temperature based on the operation rate of the compressor 23. On the other hand, the control unit 30 according to the second embodiment has at least one of the cooling start temperature and the cooling suppression temperature based on the difference between the average value of the internal temperature detected by the internal temperature sensor 20 and the internal set temperature. To change.

(1) Change of cooling suppression temperature With reference to FIG.7 and FIG.8, the internal temperature detected in 1 cycle in a normal environment and the internal temperature detected in 1 cycle in a severe environment are demonstrated. . Here, one cycle refers to a period from the start of the operation of the compressor 23 to the stop of the operation and the subsequent start of the operation.

  As shown in FIG. 7, in the normal environment, the average value of the internal temperature detected during one cycle is substantially the same as the internal set temperature. On the other hand, as shown in FIG. 8, in a severe environment, the operation time of the compressor 23 is longer than in a normal environment, so the average value of the internal temperature detected during one cycle is lower than the internal set temperature. . That is, in a severe environment, the difference between the internal average temperature and the internal set temperature becomes large.

  Therefore, the controller 30 monitors the internal temperature detected by the internal temperature sensor 20 at a predetermined time interval such as 1 second, and is detected during one cycle every time one cycle is completed. Calculate the average value of the internal temperature. And the control part 30 will raise cooling suppression temperature, if the computed average value becomes more than a reference value (for example, 1 degreeC) with respect to preset temperature in a store | warehouse | chamber. Here, also in the second embodiment, it is assumed that the changed cooling suppression temperature is fixed and determined in advance.

  By the way, if the cooling suppression temperature is kept high, when the surrounding environment returns to the normal environment, the operating rate is conversely reduced, and there is a possibility that the internal temperature inside the storage becomes higher than the internal set temperature. For this reason, it is desirable to return the cooling suppression temperature to the original when the difference between the average value of the internal temperature during one cycle and the internal set temperature returns below the reference value.

(2) Effects of the embodiment According to the open showcase according to the second embodiment described above, cooling is performed when the average value of the internal temperature detected by the internal temperature sensor 20 is lower than the reference value with respect to the internal set temperature. Since the suppression temperature is increased, the difference between the inside average temperature and the inside set temperature can be reduced without providing an outside air temperature sensor that detects the ambient temperature.

<Embodiment 3>
Next, Embodiment 3 will be described with reference to FIG.
The operating rate of the compressor 23 does not necessarily correspond to the average value of the internal temperature with high accuracy. For this reason, judging whether or not to increase the cooling suppression temperature based only on the operating rate, the cooling suppression temperature can be increased or the internal temperature can be increased despite the small difference between the average value of the internal temperature and the internal temperature setting. It cannot be said that the cooling suppression temperature is not increased even though the difference between the average value of the values and the set temperature in the cabinet is large.

  On the other hand, since the average value of the internal temperature detected by the internal temperature sensor 20 represents the average value of the actual internal temperature, it is based on the difference between the average value of the internal temperature and the set temperature in the internal storage. If the cooling suppression temperature is increased, the cooling suppression temperature can be increased or the average value of the internal temperature and the internal set temperature can be increased even though the difference between the average value of the internal temperature and the internal set temperature is small. In spite of the large difference, the cooling suppression temperature is not likely to increase. That is, it can be accurately determined whether or not the cooling suppression temperature is increased.

  However, since the internal temperature is easily affected by external factors such as the ambient temperature, the difference between the average value of the internal temperature and the internal set temperature may temporarily increase within a range where the operating rate does not change greatly. possible. Even in this case, if the cooling suppression temperature is increased, the operation of the cooling device may become unstable.

  Therefore, the control unit 30 according to the third embodiment is based on the change width of the operating rate of the compressor 23 and the difference between the average value of the internal temperature detected by the internal temperature sensor 20 and the internal set temperature. Then, at least one of the cooling start temperature and the cooling suppression temperature is changed. Specifically, in the control unit 30 according to the third embodiment, the change rate of the operation rate of the compressor 23 is equal to or greater than the first reference value, and the average value of the internal temperature is the internal set temperature. When the temperature is lower than the second reference value, the cooling suppression temperature is increased.

(1) Change of operation rate With reference to FIG. 9, the change of an operation rate is demonstrated. Each time one cycle is completed, the control unit 30 determines that the difference between the operation rate of the cycle having the highest operation rate and the operation rate of the cycle having the lowest operation rate among the last three previous cycles is the first reference value (for example, 10%) or more. If it is greater than or equal to the first reference value, it is determined that the operating rate has changed. The difference between the largest operation rate and the smallest operation rate is an example of the range of change.

  For example, in FIG. 9, when the cycle C is completed as an example, the last three cycles in the past are cycle A, cycle B, and cycle C. Here, it is assumed that the operation rate of cycle C is the largest and the operation rate of cycle A is the smallest. Further, it is assumed that the operation rate of cycle C is 70% and the operation rate of cycle A is 50%. In this case, since the difference between the largest operation rate and the smallest operation rate is 20% (= 70% -50%), the control unit 30 determines that the operation rate has changed.

(2) Change of cooling suppression temperature When the control unit 30 determines that the operation rate has changed, the average value of the internal temperature during the last one cycle among the last three cycles in the past becomes the internal set temperature. On the other hand, it is determined whether or not it is lower than a second reference value (for example, 1 ° C.). When the control unit 30 determines that the temperature is lower than the second reference value, the control unit 30 increases the cooling suppression temperature.

  By the way, the operation rate changes not only when the surrounding environment changes from the normal environment to the harsh environment but also when the environment changes from the harsh environment to the normal environment. In that case, since the last one cycle is the operation in the normal environment, the difference between the average value of the internal temperature in the single cycle and the internal set temperature is less than the second reference value. If the cooling suppression temperature is kept high, the operating rate will be reduced when returning to the normal environment, and the average temperature inside the cabinet may become higher than the set temperature inside the cabinet, so the operating rate has changed. In this case, when the difference between the average value of the internal temperature during the last one cycle and the internal set temperature is less than the second reference value, it is desirable to return the cooling suppression temperature to the original value.

(3) Correction value of cooling suppression temperature When the control unit 30 according to the third embodiment changes the cooling suppression temperature, the average value of the internal temperature detected by the internal temperature sensor 20 is the changed cooling suppression temperature. And is determined based on the difference between the set temperature in the cabinet. Specifically, when changing the cooling suppression temperature, the control unit 30 according to the third embodiment calculates a correction value using the following Equation 2. Then, the control unit 30 determines the changed cooling suppression temperature by adding the calculated correction value to the reference cooling suppression temperature.
Correction value = (Set temperature in the chamber−Average temperature in the last one cycle) / 2

(4) Effects of Embodiment According to the open showcase according to Embodiment 3 described above, the change width of the operating rate of the compressor 23 is equal to or greater than the first reference value and is detected by the internal temperature sensor 20. When the average value of the internal temperature is lower than the second reference value by the second reference value or higher, the cooling suppression temperature is increased, so that the unstable operation of the compressor 23 is suppressed and the cooling suppression temperature is increased. Whether or not to do so can be determined with high accuracy.

  Furthermore, according to the open showcase according to the third embodiment, the changed cooling suppression temperature is determined based on the difference between the average value of the internal temperature detected by the internal temperature sensor 20 and the internal set temperature. As compared with the case where the changed cooling suppression temperature is fixed and determined, there is a high possibility that the difference between the inside average temperature and the inside set temperature can be reduced.

<Embodiment 4>
Next, a fourth embodiment will be described.
The fourth embodiment is a modification of the first embodiment. The open showcase according to Embodiment 1 described above cools the interior of the cabinet, while the open showcase according to Embodiment 4 heats the interior of the cabinet. The configuration of the open showcase according to the fourth embodiment is substantially the same as the configuration of the open showcase according to the first embodiment except that a heater is provided instead of the cooler. The open showcase according to Embodiment 4 is an example of a heating device.

  The control unit 30 according to the fourth embodiment starts the operation of the heater when the internal temperature decreases to the heating start temperature, and stops the operation of the heater when the internal temperature rises to the heating suppression temperature. In the case of a heating device, if the ambient temperature is low, it is difficult to increase the internal temperature, so that the time during which the heater is operated increases. When the time during which the heater is operated becomes longer, the operating rate of the heater increases. When the operating rate of the heater increases, the average temperature inside the chamber rises more than the set temperature inside the chamber.

  Therefore, when the operating rate of the heater is equal to or higher than the reference operating rate, the control unit 30 according to the fourth embodiment reduces the heating suppression temperature so that the difference between the internal average temperature and the internal set temperature does not increase. To do. If the heating suppression temperature is lowered, the operating time of the heater is shortened, so the operating rate of the heater is lowered. When the operating rate of the heater is lowered, the internal temperature is lowered. Thereby, the deviation between the inside average temperature and the inside set temperature can be reduced.

  According to the open showcase according to the fourth embodiment described above, since the heating suppression temperature is lowered when the operating rate of the heater is equal to or higher than the reference operating rate, the inside average without the outside temperature sensor for detecting the ambient temperature is provided. The difference between the temperature and the set temperature in the cabinet can be reduced.

<Embodiment 5>
Next, Embodiment 5 will be described.
The fifth embodiment is a modification of the second embodiment. The open showcase according to the second embodiment described above cools the inside of the cabinet, while the open showcase according to the fifth embodiment heats the inside of the cabinet. The configuration of the open showcase according to the fifth embodiment is substantially the same as the configuration of the open showcase according to the second embodiment except that a heater is provided instead of the cooler. The open showcase according to Embodiment 5 is an example of a heating device.

  The control unit 30 according to the fifth embodiment starts the operation of the heater when the internal temperature decreases to the heating start temperature, and stops the operation of the heater when the internal temperature rises to the heating suppression temperature. In the case of a heating device, if the ambient temperature is low, it is difficult to increase the internal temperature, so that the time during which the heater is operated increases. When the time during which the heater is operated becomes long, the average temperature inside the chamber rises more than the preset temperature inside the chamber.

  Therefore, when the average value of the internal temperature detected by the internal temperature sensor 20 is higher than the reference value (for example, 1 ° C.) by the internal temperature sensor 20, the control unit 30 according to the fifth embodiment The heating suppression temperature is lowered so that the difference between the temperature and the set temperature in the cabinet does not increase.

  According to the open showcase according to the fifth embodiment described above, the heating suppression temperature is lowered when the average value of the internal temperature detected by the internal temperature sensor 20 is higher than the reference value with respect to the internal set temperature. The divergence between the inside average temperature and the inside set temperature can be reduced without providing an outside air temperature sensor for detecting the ambient temperature.

<Embodiment 6>
Next, Embodiment 6 will be described.
The sixth embodiment is a modification of the third embodiment. The open showcase according to Embodiment 3 described above cools the interior of the cabinet, while the open showcase according to Embodiment 6 heats the interior of the cabinet. The configuration of the open showcase according to the sixth embodiment is substantially the same as that of the open showcase according to the third embodiment except that a heater is provided instead of the cooler. The open showcase according to Embodiment 6 is an example of a heating device.

  The control unit 30 according to the sixth embodiment starts the operation of the heater when the internal temperature decreases to the heating start temperature, and stops the operation of the heater when the internal temperature rises to the heating suppression temperature. And the control part 30 which concerns on Embodiment 6 has the change width of the operating rate of a heater more than a 1st reference value, and the average value of the chamber temperature detected by the chamber temperature sensor 20 is the inside of a store | warehouse | chamber When the set temperature is higher than the second reference value, the heating suppression temperature is lowered.

  According to the open showcase according to the sixth embodiment described above, the change width of the operating rate of the heater is equal to or greater than the first reference value, and the average value of the internal temperature detected by the internal temperature sensor 20 is Since the heating suppression temperature is lowered when it is higher than the second reference value with respect to the internal set temperature, it is possible to accurately determine whether or not to lower the heating suppression temperature while suppressing unstable operation of the heater. .

  Furthermore, according to the open showcase according to the sixth embodiment, the changed heating suppression temperature is determined based on the difference between the average value of the internal temperature detected by the internal temperature sensor 20 and the internal set temperature. The possibility that the difference between the in-chamber average temperature and the in-chamber set temperature can be reduced is higher than when the changed heating suppression temperature is fixed.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and the drawings, and for example, the following embodiments are also included in the technical scope.

  (1) In the first embodiment, the case where the cooling suppression temperature is increased when the operation rate of the cooler in the past predetermined time Ta is equal to or higher than a preset reference operation rate has been described as an example. On the other hand, every time one cycle is completed, it is determined whether or not the average operation rate in the last three cycles in the past is equal to or higher than the reference operation rate. It may be. Note that the most recent three cycles in the past are examples, and for example, the operation rate of the most recent one cycle in the past may be used. The same applies to the fourth embodiment.

  (2) In the first and second embodiments, the case where the cooling suppression temperature after the change is fixed and determined in advance when the cooling suppression temperature is increased has been described as an example. On the other hand, in the first and second embodiments, similarly to the third embodiment, a temperature obtained by adding the correction value calculated by Expression 2 to the reference cooling suppression temperature may be used as the changed cooling suppression temperature. The same applies to the fourth and fifth embodiments.

  (3) In the first embodiment, the example in which the cooling suppression temperature is increased when the temperature around the cooling device is high (when the operating rate of the cooler is high) has been described. Instead of this, or in addition to this, when the temperature around the cooling device is high, the cooling start temperature may be increased. In the case of the cooling device, if the cooling start temperature is raised, the cooling machine's stop time becomes longer, so the operating rate of the cooling machine becomes lower. When the operating rate of the cooler decreases, the average value of the internal temperature increases. Thereby, the deviation between the inside average temperature and the inside set temperature can be reduced. Although the first embodiment has been described here as an example, the same applies to the second and third embodiments.

  (4) In the first embodiment, the example in which the cooling suppression temperature is increased when the temperature around the cooling device is high (when the operating rate of the cooler is high) has been described. Instead of this, or in addition to this, when the temperature around the cooling device is low (when the operating rate of the cooler is low), the cooling suppression temperature may be lowered. If the temperature around the cooling device is low, the internal temperature tends to decrease, so the operating time of the cooler is shortened. When the operation time of the cooler is shortened, the operation rate of the cooler is lowered. When the operating rate of the cooler decreases, the average value of the internal temperature increases. In this case, if the cooling suppression temperature is lowered, the operation time of the cooler becomes longer, so the operation rate of the cooler becomes higher. When the operating rate of the cooler increases, the average value of the internal temperature decreases. Thereby, the deviation between the inside average temperature and the inside set temperature can be reduced.

Further, when the temperature around the cooling device is low, the cooling start temperature may be lowered instead of lowering the cooling suppression temperature. When the cooling start temperature is lowered, the cooling machine stop time is shortened, so that the operating rate of the cooling machine is increased. When the operating rate of the cooler increases, the average value of the internal temperature decreases. Thereby, the deviation between the inside average temperature and the inside set temperature can be reduced.
Although the first embodiment has been described here as an example, the same applies to the second and third embodiments.

  (5) In the said Embodiment 4, when the temperature around the heating apparatus was low (when the operating rate of a heater was high), the case where heating suppression temperature was made low was demonstrated to the example. Instead of this, or in addition to this, when the temperature around the heating device is low, the heating start temperature may be lowered. In the case of a heating device, if the heating start temperature is lowered, the operation time of the heater is lowered because the stop time of the heater is lengthened. When the operating rate of the heater is lowered, the average value of the inside temperature is lowered. Thereby, the deviation between the inside average temperature and the inside set temperature can be reduced. Although the fourth embodiment has been described here as an example, the same applies to the fifth and sixth embodiments.

  (6) In the fourth embodiment, the example in which the heating suppression temperature is lowered when the temperature around the heating device is low (when the operating rate of the heater is high) has been described. Instead of this, or in addition to this, when the temperature around the heating device is high (when the operating rate of the heater is low), the heating suppression temperature may be increased. If the temperature around the heating device is high, the internal temperature tends to rise, so the operation time of the heater is shortened. When the operation time of the heater is shortened, the operation rate of the heater is lowered. When the operating rate of the heater is lowered, the average value of the inside temperature is lowered. In this case, since the operation time of a heater will become long when heating suppression temperature is made high, the operating rate of a heater becomes high. As the operating rate of the heater increases, the average value of the internal temperature increases. Thereby, the deviation between the inside average temperature and the inside set temperature can be reduced.

Further, when the temperature around the heating device is high, the heating start temperature may be increased instead of increasing the heating suppression temperature. If the heating start temperature is increased, the stop time of the heater is shortened, so that the operating rate of the heater is increased. As the operating rate of the heater increases, the average value of the internal temperature increases. Thereby, the deviation between the inside average temperature and the inside set temperature can be reduced.
Although the fourth embodiment has been described here as an example, the same applies to the fifth and sixth embodiments.

  (7) In the first to third embodiments, the open showcase that cools the inside of the warehouse as the cooling device has been described as an example. However, the cooling device is not limited to an open showcase as long as it cools the inside of the cabinet. For example, the cooling device may be a refrigerator or a freezer.

  In the case of a cooling device having a door such as a refrigerator, whether or not to change the cooling start temperature or the cooling suppression temperature may be determined in consideration of the frequency of opening and closing the door.

  (8) In Embodiments 4 to 6 described above, the open showcase that heats the interior as the heating device has been described as an example. However, the heating device is not limited to an open showcase as long as it heats the interior of the cabinet. For example, the heating device may be an oven or a fryer.

  In the case of a heating apparatus having a door such as an oven, whether to change the heating start temperature or the heating suppression temperature may be determined in consideration of the opening / closing frequency of the door.

  (9) In the above embodiment, the case where the control unit 30 includes the CPU 31 has been described as an example. On the other hand, the control unit 30 may include a field programmable gate array (FPGA) instead of the CPU 31. Moreover, the control part 30 may be comprised by ASIC.

DESCRIPTION OF SYMBOLS 1 ... Open showcase, 10 ... Cooling box, 20 ... Inside temperature sensor, 23 ... Compressor, 24 ... Capillary tube, 25 ... Cooling fan, 25 ... Condensation Device, 30... Control unit

Claims (4)

A cooler that cools the inside of the cabinet;
An internal temperature sensor for detecting the internal temperature,
A control unit;
With
The controller is
The inside temperature detected by the inside temperature sensor is monitored, and when the inside temperature rises to the cooling start temperature, the operation of the cooler is started, and the inside temperature reaches a cooling suppression temperature lower than the cooling start temperature. A control process that suppresses the operation of the cooler when lowered, and
Based on the change width of the operating rate of the cooler and the difference between the average value of the internal temperature detected by the internal temperature sensor and the internal set temperature, at least the cooling start temperature and the cooling suppression temperature. Change process to change one,
Perform the cooling device. The cooling device according to claim 1 ,
In the change process, the controller is configured such that a change width of the operating rate of the cooler is equal to or greater than a first reference value, and an average value of the internal temperature detected by the internal temperature sensor is the internal temperature. A cooling device that increases the cooling suppression temperature when the temperature is lower than a second reference value with respect to a set temperature. The cooling device according to claim 1 or 2 ,
In the change process, the control unit sets the cooling start temperature after the change or the cooling suppression temperature after the change between an average value of the internal temperature detected by the internal temperature sensor and the internal set temperature. A cooling device that is determined based on the difference. A heating machine for heating the inside of the cabinet;
An internal temperature sensor for detecting the internal temperature,
A control unit;
With
The controller is
The internal temperature detected by the internal temperature sensor is monitored, and when the internal temperature decreases to the heating start temperature, the operation of the heater is started, and the internal temperature reaches a heating suppression temperature higher than the heating start temperature. A control process that suppresses the operation of the heater when it rises;
Based on the change width of the operating rate of the heater and the difference between the average value of the internal temperature detected by the internal temperature sensor and the internal set temperature, at least the heating start temperature and the heating suppression temperature Change process to change one,
Perform the heating device.

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