JP2007335497A - Cooling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling device for controlling cooling operation in accordance with amount of heat generated by a heat generating material having variation in the thermal load while achieving protection of a compressor. <P>SOLUTION: A controller 40 starts operation of the compressor 22 when air temperature within a storing chamber 4 rises to the cooling start setting temperature, and stops the operation of the compressor 22 when the air temperature in the storing chamber 4 becomes equal to or lower than the predetermined cooling start setting temperature. Moreover, the controller 40 has the predetermined re-start inhibiting time from the stop of operation of the compressor 22. In the case where air temperature within the storing chamber 4 rises to the cooling start setting temperature before the re-start inhibiting time has passed after stop of the operation of the compressor 22, the controller 40 executes a cooling stop setting temperature correction mode to execute compensation for lowering the cooling stop setting temperature than the initial cooling stop setting temperature. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cooling device that cools a heating element, such as an electronic device, on which an integrated circuit element such as a CPU or LSI is mounted, to a predetermined temperature.

  In recent years, semiconductor integrated circuit elements such as CPUs and LSIs having a microelectronic circuit in which elements including a large number of semiconductors and internal wirings are combined as a single solid by a special method have come to be widely used. . An integrated circuit device having such a microelectronic circuit generates a large amount of heat during operation. When the temperature of the integrated circuit element rises, a problem that its operation becomes unstable occurs, and when the temperature rises further, the semiconductor is destroyed. Therefore, the heat sink is attached to the integrated circuit element to exchange heat between the heat sink and the air, the heat of the integrated circuit element is released into the air to cool the integrated circuit element, and the integrated circuit elements such as CPU and LSI are hot. It was prevented from causing unstable operation and thermal destruction.

  On the other hand, in a data communication network using a communication line and a computer network (LAN) that performs high-speed data transfer using a facility line within a limited range such as in a building or site, an integrated circuit element as described above is used. A server provided with a large number of electronic devices using the.

That is, in such a server, a significant temperature rise occurs due to the operation of a large number of integrated circuit elements. Therefore, for example, the server is stored in an electronic device storage furniture as disclosed in Patent Document 1, and disposed in the electronic device storage furniture. A method of cooling the integrated circuit element by a circulating fan, an air conditioner, or a heat exchanger is employed.
JP 2000-165079 A

  In the conventional electronic equipment storage furniture as described above, the server in which the integrated circuit element is arranged is stored in a rack body that completely blocks the inflow of external air, and the air cooled by the air conditioner or heat exchanger is stored in the server. The server is cooled to a predetermined temperature by circulating through the main body with a circulation fan.

  For example, as shown in FIG. 14, when the air temperature circulating in the main body rises to a predetermined cooling start temperature, the air conditioner starts the operation of the compressor constituting the air conditioner, and the air temperature Control is performed to stop the operation of the compressor when the temperature is lowered to a predetermined cooling stop temperature.

  On the other hand, the compressor which comprises an air conditioner is the control which prohibits a restart for the predetermined time, for example, about 1 to 3 minutes, after stopping the operation of a compressor for the purpose of protection of this compressor. Is running.

  Therefore, even if the heat load in the rack body is increasing, as shown in FIG. 15, the compressor is prohibited from being restarted for a predetermined time after the compressor is stopped. Even if the air temperature inside rises to the cooling start temperature, the compressor cannot be restarted. As a result, for example, the temperature may increase by about 10 ° C. from the cooling stop temperature due to the heat generated by a heating element such as a server or the influence of the installation environment before the time for prohibiting the restart has elapsed. Therefore, after the restart prohibition time has elapsed, when the compressor can be restarted, the air temperature in the main body has already exceeded the target air temperature, and the server as a heating element There is a risk of unstable operation and thermal destruction due to high temperatures.

  Therefore, it is conceivable to set the cooling temperature in the rack body in accordance with the maximum heat generation amount of the heating element such as a server accommodated in the rack body. Therefore, if the cooling control is performed according to the maximum heat generation when the heat load is small, the inside of the rack body is cooled more than necessary, which causes the problem of condensation. To do.

  Therefore, the present invention has been made to solve the conventional technical problem, and it is possible to control cooling according to the amount of heat generated by a heating element having a variation in thermal load while protecting the compressor. A cooling device is provided.

  The cooling device of the present invention includes a storage chamber for storing a heating element, and a cooling unit in which a refrigerant circuit is configured by a compressor, a condenser, a decompression device, an evaporator, and the like, and blows the cold air exchanged with the evaporator. The heating device is cooled by being circulated in the storage chamber, and includes a control device that controls the operation of the compressor based on the air temperature in the storage chamber. The compressor starts operating when the temperature reaches a predetermined cooling start set temperature, and when the air temperature in the storage chamber decreases to a predetermined cooling stop set temperature, the compressor stops operating and the compressor stops. If the air temperature in the storage room rises to the cooling start set temperature after the compressor has stopped and before the restart prohibition time has elapsed, the cooling stop set temperature is initially cooled. Below the stop set temperature That and executes a cooling stop temperature setting correction mode for correcting.

  In the cooling device according to the second aspect of the present invention, in the above invention, when the control device performs correction to lower the cooling stop set temperature, the temperature of the storage chamber at the time when the restart prohibition time has elapsed and the cooling start set temperature are calculated. Based on the difference T1 and / or the elapsed time t1 until the temperature in the storage chamber rises from the cooling stop set temperature to the cooling start set temperature, the decrease in the cooling stop set temperature is increased as the difference T1 increases. As the time t1 is longer, the lowering amount is determined in such a direction that the lowering amount of the cooling stop set temperature is reduced.

  According to a third aspect of the present invention, there is provided a cooling device according to the above invention, wherein the control device corrects the cooling set temperature and the air temperature in the storage chamber is cooled even after the restart prohibition time has elapsed since the compressor was stopped. When the temperature does not rise to the start set temperature, correction for increasing the cooling stop set temperature is performed.

  According to a fourth aspect of the present invention, in the above invention, when the control device performs correction for increasing the cooling stop set temperature, the cooling start set temperature and the temperature in the storage chamber at the time when the restart prohibition time has elapsed are determined. Based on the difference T2 and / or the elapsed time t2 from when the temperature in the storage room elapses to the cooling start set temperature after the restart prohibition time has elapsed, the increase in the cooling stop set temperature is increased as the difference T2 increases. As the elapsed time t2 is shorter, the increase amount is determined in the direction of decreasing the increase amount of the cooling stop set temperature.

  The cooling device of the invention of claim 5 includes a storage chamber for storing a heating element, and a cooling unit in which a refrigerant circuit is configured by a compressor, a condenser, a decompression device, an evaporator, and the like, and exchanges heat with the evaporator. Cooling air is circulated into the storage chamber by a blower to cool the heating element, and includes a control device that controls the operation of the compressor and the blower based on the air temperature in the storage chamber. When the air temperature in the room rises to a predetermined cooling start set temperature, the operation of the compressor is started, and when the air temperature in the storage room falls to a predetermined cooling stop set temperature, the operation of the compressor is stopped, When the heat generation amount of the heating element is equal to or greater than a predetermined value, the circulating air volume in the storage chamber by the blower is initially circulated without stopping the operation of the compressor even if the air temperature in the storage chamber falls to the cooling stop set temperature. Decreased than air volume And executes the Rukazeryou control mode.

  The cooling device according to a sixth aspect of the present invention is characterized in that, in the above invention, the control device estimates the amount of heat generated by the heating element based on the rate of change of the air temperature in the storage chamber and / or the outside air temperature.

  According to a seventh aspect of the present invention, there is provided a cooling device according to the fifth or sixth aspect of the present invention, wherein, after the controller reduces the circulating air volume, when the air temperature in the storage chamber rises to the cooling start set temperature, it is stored by the blower. It is characterized by returning the indoor circulating air volume to the initial circulating air volume.

  The cooling device according to an eighth aspect of the present invention is the cooling device according to any one of the fifth to seventh aspects, wherein the control device reduces the circulating air volume before the air temperature in the storage chamber rises to the cooling start set temperature. When the evaporation temperature of the refrigerant in the evaporator decreases to a predetermined lower limit temperature, the operation of the compressor is stopped, and the circulating air volume in the storage chamber by the blower is returned to the initial circulating air volume.

  In the cooling device of the ninth aspect of the invention, the control device is the cooling stop set temperature correction mode according to any one of the first to fourth aspects and the air volume control mode according to any one of the fifth to eighth aspects. Are executed in combination.

  According to the present invention, a storage chamber that stores a heating element and a cooling unit in which a refrigerant circuit is configured by a compressor, a condenser, a decompression device, an evaporator, and the like are provided. A cooling device that cools the heating element by circulating in the storage chamber, and includes a control device that controls the operation of the compressor based on the air temperature in the storage chamber. The control device controls the air temperature in the storage chamber. The compressor starts operating when the temperature reaches a predetermined cooling start set temperature, and when the air temperature in the storage chamber decreases to a predetermined cooling stop set temperature, the compressor stops operating and the compressor stops. If the air temperature in the storage room rises to the cooling start set temperature after the compressor has stopped and before the restart prohibition time has elapsed, the cooling stop set temperature is initially cooled. Below the stop set temperature When the cooling stop set temperature correction mode is performed, the load change caused by the heating element in the storage chamber occurs, and the cooling stop set temperature is set to the initial set temperature when the air temperature in the storage chamber tends to rise. By making the correction to be lower than this, it is possible to delay the time during which the air temperature in the storage chamber rises to the cooling start set temperature before the restart prohibition time provided for protecting the compressor elapses.

  As a result, it is possible to suppress the inconvenience that the air temperature in the storage room rises to the cooling start set temperature before the compressor restart prohibition time elapses, and the storage room temperature rises remarkably. It is possible to suppress or avoid inconvenience that adversely affects the generated heating element.

  According to the invention of claim 2, in the above invention, when the control device performs correction to lower the cooling stop set temperature, the difference between the temperature in the storage chamber and the cooling start set temperature when the restart prohibition time has elapsed. Based on T1 and / or the elapsed time t1 until the temperature in the storage chamber rises from the cooling stop set temperature to the cooling start set temperature, the amount of decrease in the cooling stop set temperature is increased as the difference T1 increases, and the elapsed time t1. Since the lowering of the cooling stop set temperature is determined in a direction to decrease the longer the is, the cooling stop set temperature is set according to the change tendency based on the change of the air temperature in the storage room due to the load in the storage room. It becomes possible to correct.

  This makes it possible to correct the cooling stop set temperature appropriately based on the air temperature change in the storage room, causing inconvenience such as the occurrence of condensation due to the cooling of the storage room more than necessary, and insufficient cooling. Such inconvenience can be effectively avoided.

  Further, according to the invention of claim 3, in each of the above inventions, after the control device performs the correction to lower the cooling set temperature, the air temperature in the storage chamber remains even if the restart prohibition time has elapsed since the compressor stopped. If the temperature does not rise to the cooling start set temperature, increase the cooling stop set temperature to increase the cooling stop set temperature when the cooling load is reduced by reducing the load caused by the heating element in the storage room. This makes it possible to effectively avoid inconveniences caused by cooling the storage chamber more than necessary.

  According to the invention of claim 4, in the above invention, when the control device performs correction to increase the cooling stop set temperature, the difference between the cooling start set temperature and the temperature in the storage chamber at the time when the restart prohibition time has elapsed. Based on T2 and / or the elapsed time t2 from when the temperature in the storage room has risen to the cooling start set temperature after the restart prohibition time has elapsed, the increase in the cooling stop set temperature is increased as the difference T2 increases. As the elapsed time t2 is shorter, the amount of increase in the cooling stop set temperature is determined in a direction that decreases, so the time from reaching the cooling stop set temperature and stopping the compressor until the point when the restart prohibition time has elapsed Changes in the air temperature in the storage room due to the load in the storage room during the period, and / or in the storage room due to the load in the storage room from the time when the restart prohibition time has elapsed until the cooling start set temperature is reached Based on the change in air temperature, cooling stop temperature setting can be corrected in a direction to increase the in accordance with the trend of the change.

  As a result, after the cooling stop set temperature is corrected, it can be corrected again to an appropriate one based on the air temperature change in the storage chamber, and condensation occurs due to cooling of the storage chamber more than necessary. Inconveniences such as these and inconveniences such as insufficient cooling can be effectively avoided.

  According to the fifth aspect of the present invention, the cool air comprising the storage chamber for storing the heating element, and the cooling unit in which the refrigerant circuit is configured by the compressor, the condenser, the decompression device, the evaporator, and the like, and exchanges heat with the evaporator. Is a cooling device that cools the heating element by circulating the air in the storage chamber using a blower, and includes a control device that controls the operation of the compressor and the blower based on the air temperature in the storage chamber. When the air temperature in the room rises to a predetermined cooling start set temperature, the operation of the compressor is started, and when the air temperature in the storage room falls to a predetermined cooling stop set temperature, the operation of the compressor is stopped, When the heat generation amount of the heating element is equal to or greater than a predetermined value, the circulating air volume in the storage chamber by the blower is initially circulated without stopping the operation of the compressor even if the air temperature in the storage chamber falls to the cooling stop set temperature. Decreased than air volume When the heat generation amount of the heating element in the storage chamber is equal to or higher than a predetermined value, the circulation air volume in the storage chamber by the blower is decreased after the temperature is reduced to the cooling stop set temperature. It is possible to avoid that the temperature in the storage chamber is lower than the cooling stop set temperature without stopping the compressor.

  Therefore, when the compressor is stopped, in order to protect the compressor, even if the air temperature in the storage chamber reaches the cooling start set temperature until the predetermined restart prohibition time has elapsed. However, in the present invention, the air temperature in the storage chamber is lower than the cooling stop set temperature by reducing the circulating air volume in the storage chamber without stopping the compressor. It is possible to avoid the decrease.

  Further, in the above invention, when the control device reduces the circulating air volume as in the invention of claim 7 and the air temperature in the storage chamber rises to the cooling start set temperature, the circulating air volume in the storage chamber by the blower is set to the initial circulating air volume. By returning to, air stored in the evaporator when the circulating air volume is reduced can be circulated into the storage chamber, and the storage chamber can be effectively cooled.

  Accordingly, when the heat generation amount of the heating element is equal to or greater than a predetermined value, the air temperature control mode is executed, so that the air temperature in the storage chamber can be reduced in a short time, for example, the time required for the compressor restart prohibition time to elapse. Even when the temperature rises above the cooling start set temperature, it is possible to appropriately control the cooling of the storage chamber by controlling the amount of circulating air in the storage chamber by the blower. This eliminates the need to wait for the compressor restart prohibition time to elapse, even though the air temperature in the storage room has reached the cooling start set temperature. It is possible to suppress or avoid inconveniences that adversely affect the housed heating elements.

  According to the invention of claim 6, in the above invention, the control device estimates the amount of heat generated by the heating element based on the rate of change of the air temperature in the storage room and / or the outside air temperature. Without specifically measuring the heat generation amount of the heating element housed in the storage room, the heat generation amount of the heating element is estimated based on the rate of change of the air temperature in the storage room and / or the outside air temperature, and the air volume control mode Can be executed. Thereby, it is possible to realize appropriate cooling control.

  According to the invention of claim 8, in the invention of any one of claims 5 to 7, after the controller reduces the circulating air volume, before the air temperature in the storage chamber rises to the cooling start set temperature, When the evaporation temperature of the refrigerant in the evaporator falls to a predetermined lower limit temperature, the compressor operation is stopped, and the circulating air volume in the storage chamber by the blower is returned to the initial circulating air volume. It is possible to avoid the occurrence of liquid return to the compressor and the occurrence of dew condensation that occurs when the cooling load decreases.

  In addition, after stopping the operation of the compressor, by returning the circulating air volume in the storage chamber by the blower to the initial circulating air volume, the air stored in the evaporator when the circulating air volume is reduced is circulated into the storage chamber. Therefore, the inside of the storage room can be effectively cooled.

  According to the ninth aspect of the present invention, the control device performs the cooling stop set temperature correction mode according to any one of the first to fourth aspects and the air volume control mode according to any one of the fifth to eighth aspects. By executing in combination, it is possible to adjust the number of start-stops of the compressor and the number of start-stops of the blower, and while suppressing the inconvenience that the air temperature in the storage chamber rises to the cooling start set temperature, the compressor And the durability of the blower can be improved.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view of a cooling device 1 to which the present invention is applied, FIG. 2 is a longitudinal side view of the cooling device 1, and FIG. 3 is a view for explaining the flow of cold air in the cooling device 1.

  The cooling device 1 of the present embodiment is a device for cooling a heating element such as a server 2 serving as a center for providing various services to a computer connected to a network, for example. The heating element is not limited to the server 2, but itself generates heat, and the heat generation causes malfunction or malfunction, and further, cooling of things that do not like the entry of condensed water or the like. It is suitable. Note that this embodiment is intended for cooling a single or a plurality of servers 2 having a circuit board on which a plurality of semiconductor integrated circuit elements such as LSIs and CPUs are mounted as heating elements.

  The cooling device 1 has a main body constituted by a cabinet 3 that opens to the front and rear surfaces. In addition, since the cabinet 3 in this embodiment sets the cooling set temperature of the server 2 to be cooled to about + 30 ° C., in particular, it has heat insulation in consideration of heat dissipation efficiency in relation to the outside air temperature. It is not necessary.

  A storage chamber 4 that opens to the front and rear surfaces is formed in the cabinet 3, and a plurality of servers 2... Can be stored in the storage chamber 4 in the vertical direction. In the storage chamber 4, for example, columns (not shown) are erected on the left and right inner walls, and each server 2 can be independently fixed to the columns by screws or the like. The front and rear openings of the storage chamber 4 are openable and closable by a front door 5 and a rear door 6 (not shown in FIG. 1, only shown in FIG. 2) provided with glass that can be seen through the inside. Is blocked. The doors 5 and 6 may be provided with a locking mechanism for safety management such that the server 2 or the like housed inside cannot be operated by a person other than the administrator.

  A pedestal angle 7 having a predetermined height is attached to the bottom surface of the cabinet 3, and both side surfaces of the pedestal angle 7 are covered with a decorative panel 8 together with both side surfaces of the cabinet 3. Thereby, a machine room 9 is formed below the cabinet 3. A pair of fixing members 10 are attached to the front and rear lower sides of the base leg angle 7 that fixes the bottom of the machine room 9. In addition, on the bottom wall 3 </ b> A of the cabinet 3, a cold air discharge port 12 and a cold air suction port 11 penetrating vertically are formed in the front and rear, respectively.

  On the bottom surface of the bottom wall 3 </ b> A of the cabinet 3 that becomes the ceiling of the machine room 9, a heat-insulating cooling box 14 having an opening on the top surface is provided in contact. A cooling chamber 15 is formed inside the cooling box 14, and an evaporator 16 constituting a cooling unit R together with a compressor 22 to be described later, and a cool air circulation fan 17 is disposed on the cool air outflow side of the evaporator 16. The A cooling air discharge port 19 and a cold air suction port 18 on the cooling box 14 side are formed in the upper surface opening of the cooling box 14 by a partition plate (not shown). The cold air outlet 19 and the cold air inlet 18 respectively correspond to the cold air outlet 12 and the cold air inlet 11 formed in the bottom wall 3 </ b> A of the cabinet 3. In addition, a sealing material (not shown) is attached to the opening edge of the cooling box 14 so as to come into close contact with the lower surface of the bottom wall 3 </ b> A of the cabinet 3.

  On the other hand, a front duct 27 is formed between the front door 5 constituting the front surface of the cabinet 3 and the front wall of each server 2 accommodated in the storage chamber 4 with a predetermined interval. The cool air discharged by the cool air circulation fan 17 from the cool air discharge port 12 formed in the bottom wall 3A rises up the front duct 27. Thereby, cold air is efficiently supplied into the storage chamber 4.

  Further, a vent hole (not shown) is formed on the front surface of each server 2, and a blower 2 </ b> A that sucks air from the front surface and discharges air to the rear is attached to the vent hole. The blower 2A of each server 2 can be operated and controlled independently. By operating the blower 2A, the cool air rising through the front duct 27 is passed through the server 2 provided with the blower 2A. Is possible.

  Therefore, in the cooling device 1, the cool air discharged from the inside of the cooling chamber 15 passes through each server 2 by the operation of each blower 2A while ascending the front duct 27 as shown in FIG. After being discharged from the rear of the cabinet 3, a cool air circulation fan is provided in a cooling chamber 15 that flows between the rear door 6 constituting the back of the cabinet 3 and the back of each server 2 and is formed below the cabinet 3. 17 returns to the cooling chamber 15 through the cold air inlets 11 and 18. Thereby, the server 2 as a heat generating body accommodated in the storage chamber 4 is cooled. In this embodiment, it is assumed that the internal temperature sensor 32 as a means for detecting the temperature in the storage chamber 4 is attached in the vicinity of the cold air inlet 11 located on the storage chamber 4 side.

  On the other hand, a mounting base 21 that forms the bottom of the cooling unit R is housed in the machine room 9. The mounting base 21 includes a compressor 22 that forms an annular refrigerant circuit together with the evaporator 16, a condenser. A fan 23, a condenser blower 24, a control box 25, and the like are provided. Casters 21 </ b> A are attached to the four corners of the lower surface of the mounting base 21. An openable / closable panel 26 is attached to the front surface of the machine room 9 to conceal the machine room 9. The panel 26 has a plurality of air holes (not shown) corresponding to the front of the condenser 23.

  Here, the evaporator 16 in the cooling box 14 includes the compressor 22, the condenser 23, and the electronic expansion, as shown in the refrigerant circuit diagram of FIG. A refrigerant circuit 29 is formed by sequentially connecting the valve (expansion valve) 28 and the evaporator 16 in an annular manner. A predetermined amount of refrigerant is sealed in the refrigerant circuit 29. Thereby, a well-known refrigerant circuit is comprised.

  Further, an evaporator inlet temperature sensor 30 and an evaporator outlet temperature sensor 31 for detecting the respective refrigerant temperatures are provided on the refrigerant inlet side and the refrigerant outlet side of the evaporator 16. In the present embodiment, the temperature on the refrigerant inlet side of the evaporator 16 is the evaporation temperature of the refrigerant in the evaporator 16. Further, the difference between the evaporator inlet temperature and the evaporator outlet temperature (evaporator outlet temperature−evaporator inlet temperature) represents the degree of superheat. That the degree of superheat is large means that the refrigerant is well evaporated in the evaporator 16 by the amount of the degree of superheat and the load is large. In addition, the fact that the degree of superheat is small means that the refrigerant is not so much evaporated in the evaporator 16 and the load is small.

  The electronic expansion valve 28 controls the flow rate of the refrigerant flowing in the refrigerant circuit 29 to depressurize the condensed refrigerant, and opens the valve according to the cooling load, that is, the degree of superheat in the evaporator 16 as described above. The degree is adjusted.

  Further, the compressor 22 in this embodiment is not an inverter-type compressor that can control the rotation speed exceptionally, but is based on the air temperature in the storage chamber 4, that is, the internal temperature, by the control device 40 described later. This is a constant speed compressor capable of controlling operation-stop by ON-OFF control.

  The condenser 23 in this embodiment has a condenser outlet temperature sensor 33 for detecting the temperature of the air that is sucked into the machine chamber 9 by the condenser blower 24 and heat-exchanged with the condenser 23. Is provided.

  Next, the control device 40 for controlling the cooling device 1 in the present embodiment will be described with reference to the electric block diagram of FIG. The control device 40 is configured by a general-purpose microcomputer, and on the input side, an evaporator inlet temperature sensor 30 for detecting the refrigerant inlet temperature of the evaporator 16 (evaporation temperature of the refrigerant in the evaporator), and the evaporator 16. An evaporator outlet temperature sensor 31 for detecting the refrigerant outlet temperature, an internal temperature sensor 32 for detecting the temperature in the storage chamber 4, and a condenser outlet temperature sensor 33 for detecting the temperature after flowing out of the condenser 23. It is connected. Moreover, the electronic expansion valve 28, the compressor 22, the cool air circulation fan 17, and the condenser blower 24 are connected to the output side. It is assumed that a control panel (not shown) is connected to the input side of the control device 40.

  Here, the compressor 22 in the present embodiment is a constant speed compressor as described above, and is connected in parallel to the AC power source 35 together with the condenser blower 24, and is ON / OFF controlled based on the output from the control device 40. The switch 36 is controlled. Thereby, based on the output from the control apparatus 40, the compressor 22 and the condenser fan 24 are operated and controlled in synchronization. On the other hand, the cold air circulation fan 17 provided in the cooling chamber 15 is connected via an inverter 37. Therefore, based on the output from the control device 40, the cold air circulation fan 17 is controlled in rotational speed independently of the compressor 22 and the like.

  With the above configuration, when the operation of the cooling device 1 is started by operating the control panel, the control device 40 outputs the output of the internal temperature sensor 32, the evaporator inlet temperature sensor 30, and the evaporator outlet temperature sensor. Based on the output of 31, the compressor 22, the condenser blower 24, and the cool air circulation fan 14 are controlled.

  Specifically, the cooling device 1 in the present embodiment accommodates a server 2 as a heating element in a storage chamber 4, and efficiently cools the heat generated from the server 2 to the server 2. In order to prevent the occurrence of dew condensation, the cooling set temperature in the storage chamber 4 is assumed to be + 30 ° C., for example.

  Therefore, when the temperature in the storage chamber 4 detects a predetermined cooling start set temperature, for example, + 33 ° C., based on the output of the internal temperature sensor 32, the control device 40 turns on the compressor 22 and the condenser blower 24. When a predetermined cooling stop set temperature, for example, + 27 ° C., is detected, the compressor 22 and the condenser blower 24 are stopped. Thereby, the inside of the storage chamber 4 can be maintained at a temperature around + 30 ° C. For the purpose of protecting the compressor, the compressor 22 executes a control for prohibiting the restart for a predetermined restart prohibition time, for example, 3 minutes after the stop. Further, when the temperature detected by the internal temperature sensor 32 is + 35 ° C. or higher, the control device 40 abnormally increases the internal temperature by the high-temperature alarm means configured by a buzzer, a lamp, and the like. This shall be notified to the user.

  On the other hand, the heat generation amount of the server 2 as the heating element accommodated in the storage chamber 4 varies depending on the use situation. Therefore, if the usage amount of the server 2 increases rapidly during the cooling operation, the cooling load increases, the cooling efficiency deteriorates, and the time to reach the cooling stop set temperature is delayed. Nevertheless, since the controller 40 stops the operation of the compressor 22 when the internal temperature reaches the cooling stop set temperature, the restart prohibition time is required to restart the compressor 22. If the internal temperature reaches the cooling start set temperature during the standby, the compressor 22 cannot be restarted.

  In view of this situation, the controller 40 in the present embodiment reduces the internal temperature (the air temperature in the storage chamber 4) to the initial cooling stop set temperature (+ 27 ° C. in the present embodiment), and operates the compressor 22. During the cooling operation before stopping the operation or after the operation of the compressor 22 is stopped, the amount of use of the server 2 suddenly increases, so that the internal temperature is set to start cooling before the restart prohibition time elapses. When the temperature rises (see FIG. 6) (see FIG. 6), the cooling stop set temperature correction mode is executed.

  In addition, the load in the storage chamber 4 is not changed only by the use state by the server 2 as the heating element, but is also changed by, for example, sunshine or an increase in outside air temperature due to the installation environment. In the correction mode, the internal temperature has decreased or increased to the set temperature, when the set temperature has exceeded the set temperature or has fallen below the set temperature, and has become equal to or higher than the set temperature. In any case, it may be any case.

  In this cooling stop set temperature correction mode, the control device 40 corrects the initial cooling stop set temperature by a predetermined temperature based on the rising tendency of the internal temperature during the restart prohibition time of the compressor 22, and the compressor 22. The restart condition of the compressor 22 after restarting is performed based on the corrected cooling stop set temperature.

  Specifically, as shown in FIG. 7, the difference T1 between the internal temperature at the time when the restart prohibition time of the compressor 22 has elapsed and the cooling start set temperature, and the internal temperature are the cooling stop set temperature (in this case) Based on the elapsed time t1 from when the temperature increases to (+ 27 ° C.) to the cooling start set temperature (in this case, + 33 ° C.), a correction temperature for decreasing the cooling stop set temperature is determined.

  FIG. 8 shows a table of correction temperatures determined from the difference T1 in the cooling stop set temperature correction mode and the elapsed time t1. For example, the difference T1 between the internal temperature at the time when the restart prohibition time has elapsed and the cooling start set temperature is 1 ° C. (that is, the internal temperature at the time when the actual restart prohibition time has elapsed in this embodiment) When the elapsed time t1 from when the cooling stop set temperature is increased to the cooling start set temperature is 1 minute, the control device 40 decreases the cooling stop set temperature by 3 ° C. In this embodiment, the corrected cooling stop set temperature is + 24 ° C.

  In addition, the difference T1 between the internal temperature at the time when the restart prohibition time has elapsed and the cooling start set temperature is 5 ° C. (that is, in this embodiment, the internal temperature at the time when the actual restart prohibition time has elapsed) When the elapsed time t1 from the cooling stop set temperature to the cooling start set temperature is 1 minute, the control device 40 lowers the cooling stop set temperature by 7 ° C. In this embodiment, the correction cooling stop set temperature is + 20 ° C. In this case, since the internal temperature is + 35 ° C. or higher, the control device 40 notifies the user that the internal temperature is abnormally increased by the high temperature alarm means described above.

  As described above, the correction for increasing the cooling stop set temperature is increased as the difference T1 between the internal temperature at the time when the restart prohibition time has elapsed and the cooling start set temperature is larger.

  As a result, the internal temperature decreases to the cooling stop set temperature when the air temperature in the storage chamber 4 is largely increased due to the load of the server 2 as a heating element in the storage chamber 4 or the load due to the installation environment. After the compressor 22 stops, the air in the storage chamber 4 is aired before the restart prohibition time provided for protecting the compressor 22 by correcting the cooling stop set temperature to be lower than the initial set temperature. It is possible to delay the time for the temperature to rise to the cooling start set temperature.

  Therefore, it is possible to suppress the inconvenience that the air temperature in the storage chamber 4 rises to the cooling start set temperature before the restart prohibition time of the compressor 22 elapses, and the temperature in the storage chamber 4 increases significantly. It is possible to suppress or avoid inconvenience that adversely affects the server 2 as a heating element housed inside.

  In particular, the correction for lowering the cooling stop set temperature is, as described above, the lower the cooling stop set temperature as the difference T1 between the internal temperature at the time when the restart prohibition time has elapsed and the cooling start set temperature is larger. Since the correction to increase is performed, the change in the air temperature in the storage chamber 4 due to the load of the storage chamber 4 from when the cooling stop set temperature is reached and the compressor is stopped until the restart prohibition time elapses. Based on this, it becomes possible to correct the cooling stop set temperature according to the tendency of the change.

  As a result, the larger the heat generation load by the server 2 is, the larger the correction range for lowering the cooling stop set temperature is, so that the next time the internal temperature drops to the cooling stop set temperature and the compressor 22 is restarted. It is possible to suppress the inconvenience that the internal temperature rises to the cooling start set temperature before the prohibition time elapses.

  In this embodiment, the difference T1 between the internal temperature at the time when the restart prohibition time has elapsed and the cooling start set temperature is 1 ° C., and the temperature rises from the cooling stop set temperature to the cooling start set temperature. When the elapsed time t1 is 1 minute, the control device 40 corrects the cooling stop set temperature by 3 ° C., the difference T1 is also 1 ° C., and the cooling start set temperature is changed from the cooling stop set temperature. When the elapsed time t1 until it rises to 3 minutes is 3 minutes, the control device 40 corrects the cooling stop set temperature by 1 ° C.

  In this way, correction is performed to decrease the cooling stop set temperature as the elapsed time t1 until the air temperature in the storage chamber 4 rises from the cooling stop set temperature to the cooling start set temperature is longer.

  As a result, after the internal temperature drops to the cooling stop set temperature and the compressor 22 stops, the increase in the air temperature in the storage chamber 4 increases due to fluctuations in the load in the storage chamber 4. The longer the elapsed time t1 until the air temperature in the storage chamber 4 rises from the cooling stop set temperature to the cooling start set temperature, the smaller the correction width for lowering the cooling stop set temperature, the higher the difference T1. It is possible to adjust the amount of decrease in the set cooling stop temperature to be corrected based on the rising time.

  Therefore, based on the change in the air temperature in the storage chamber from when the cooling stop set temperature is reached and the compressor 22 is stopped until the restart prohibition time elapses and until the cooling start set temperature is reached. The cooling stop set temperature can be corrected in accordance with the change tendency.

  As a result, the correction of the cooling stop set temperature can be made appropriate based on the change in the air temperature in the storage chamber 4, and inconvenience such as the occurrence of condensation due to the cooling of the storage chamber 4 more than necessary. In addition, inconveniences such as insufficient cooling can be effectively avoided.

  On the other hand, after performing the correction to lower the cooling stop set temperature based on the raised internal temperature as described above, for example, when the amount of heat generated by the server 2 as the heating element stored in the storage chamber 4 decreases, Since the temperature is corrected to lower the cooling stop set temperature, the temperature is lower than the target internal temperature, which is + 30 ° C. in this embodiment. Therefore, the control device 40 corrects the corrected cooling stop set temperature (corrected cooling stop set temperature) again.

  When the internal temperature does not rise to the cooling start set temperature even after the restart prohibition time has elapsed since the compressor 22 stopped because the internal temperature has decreased to the corrected cooling stop set temperature, Based on the rising tendency that the internal temperature rises from the corrected cooling stop set temperature to the cooling start set temperature, the compressor 22 is corrected after the corrected cooling stop set temperature is increased by a predetermined temperature and the compressor 22 is restarted. The stop condition is performed based on the corrected cooling stop set temperature after increasing the temperature.

  Specifically, as shown in FIG. 9, the difference T2 between the cooling start set temperature and the internal temperature when the restart prohibition time of the compressor 22 has elapsed, and the time when the internal temperature has exceeded the restart prohibition time. The correction temperature for increasing the cooling stop set temperature is determined based on the elapsed time t2 from when the temperature is increased to the cooling start set temperature.

  FIG. 10 shows a table of correction temperatures determined from the difference T2 in the cooling stop set temperature correction mode and the elapsed time t2. For example, the difference T2 between the cooling start set temperature (+ 33 ° C. in this embodiment) at the time when the restart prohibition time has elapsed and the internal temperature is 5 ° C. (that is, the actual restart prohibition time in this embodiment). When the internal temperature is + 28 ° C.), the elapsed time t2 from when the internal temperature has passed the restart prohibition time to when the internal temperature rises to the cooling start set temperature is 1 minute. In this case, the control device 40 corrects the corrected cooling stop set temperature by 3 ° C.

  Further, the difference T2 between the cooling start set temperature (+ 33 ° C. in the present embodiment) at the time when the restart prohibition time has elapsed and the internal temperature is 1 ° C. (that is, the actual restart prohibition time in this embodiment). When the internal temperature is + 32 ° C.), the elapsed time t2 from when the internal temperature has passed the restart prohibition time to when the internal temperature rises to the cooling start set temperature is 1 minute. In this case, the control device 40 does not perform correction for increasing the corrected cooling stop set temperature by 0 ° C., that is, does not perform correction, and maintains the previously determined corrected cooling stop set temperature.

  In this way, correction is performed to increase the cooling stop set temperature as the difference T2 between the cooling start set temperature and the internal temperature at the time when the restart prohibition time of the compressor 22 has elapsed is larger. However, when performing the correction to increase the cooling stop set temperature, if the cooling stop set temperature exceeds the initial cooling stop set temperature, which is + 27 ° C. in this embodiment, by the determined correction width, It is assumed that the upper limit temperature of the cooling stop set temperature is the initial cooling stop set temperature.

  As a result, after the correction to lower the cooling stop set temperature is performed, when the tendency of the air temperature in the storage chamber 4 to decrease due to the load in the storage chamber 4 is large, the correction to increase the corrected cooling stop set temperature is performed again. Thus, for example, when the cooling load in the storage chamber 4 decreases according to the usage state of the server 2 as a heating element in the storage chamber 4 and the installation environment, the cooling stop set temperature can be increased. Inconvenience due to the inside of the storage chamber 4 being cooled more than necessary can be effectively avoided.

  In particular, in the correction for increasing the cooling stop set temperature, as described above, the increase in the cooling stop set temperature is increased as the difference T2 between the cooling start set temperature and the internal temperature at the time when the restart prohibition time has elapsed is larger. Since the correction is performed, the temperature is reached based on the change in the air temperature in the storage chamber 4 due to the load of the storage chamber 4 from when the cooling stop set temperature is reached and the compressor is stopped until the restart prohibition time elapses. Thus, it is possible to perform correction for increasing the cooling stop set temperature in accordance with the tendency of the change.

  As a result, after the correction for lowering the cooling stop set temperature is performed, as the heat generation load by the server 2 decreases, the correction range for raising the cooling stop set temperature is increased, so that the internal temperature is set to the cooling stop next time. It becomes possible to make cooling control according to the situation in the storage chamber 4 more when the temperature is lowered and the compressor 22 is operated again. Therefore, for example, in spite of the fact that the heat generation load due to the heat generating element is decreasing, the cooling stop set temperature is corrected to be low so that the inside of the refrigerator cools down and the heat generating element or the like may cause inconvenience. It is possible to avoid it.

  Further, in this embodiment, the difference T2 between the cooling start set temperature (+ 33 ° C. in this embodiment) at the time when the restart prohibition time has elapsed and the inside temperature is 2 ° C. (that is, in the present embodiment, actual Is the temperature at the time when the restart prohibition time elapses is + 31 ° C.), and the elapsed time t2 from when the cooler temperature has passed the restart prohibition time until the cooling start set temperature is increased. Is one minute, the control device 40 does not perform correction for increasing the corrected cooling stop set temperature by 0 ° C., ie, does not perform correction, and maintains the previously determined corrected cooling stop set temperature.

  On the other hand, when the difference T2 between the cooling start set temperature at the time when the restart prohibition time has elapsed and the internal temperature is 2 ° C., the internal temperature is set to the restart prohibition time. When the elapsed time t2 from when the time has elapsed until the temperature starts to rise to the cooling start set temperature is 3 minutes, the control device 40 performs correction to increase the corrected cooling stop set temperature by 2 ° C.

  Thus, the control apparatus 40 performs correction | amendment which makes the raise width | variety of cooling stop setting temperature small, so that the elapsed time t2 until it rises to cooling start setting temperature from the point in time when the inside temperature passes restart prohibition time is short.

  As a result, after the correction for lowering the cooling stop set temperature, the air temperature in the storage chamber 4 is largely decreased due to the load in the storage chamber 4, and the restart of the air temperature in the storage chamber 4 is prohibited. The shorter the elapsed time t2 until the temperature starts to rise to the cooling start set temperature after the time has elapsed, the smaller the correction range for raising the cooling stop set temperature, the smaller the cooling stop set temperature corrected by the difference T2. The raising width can be adjusted based on the rising time.

  Therefore, the change in the air temperature in the storage chamber 4 due to the load in the storage chamber 4 from the time when the cooling stop set temperature is reached and the compressor 22 is stopped to the time when the restart prohibition time has elapsed, Direction of increasing the cooling stop set temperature according to the change tendency based on the change in the air temperature in the storage chamber 4 due to the load fluctuation of the server 2 from the time when the start prohibition time has elapsed until the cooling start set temperature is reached. It becomes possible to correct to.

  As a result, after correction for lowering the cooling stop set temperature is performed, it can be corrected again to a more appropriate one based on a change in the air temperature in the storage chamber 4, and the storage chamber 4 is cooled more than necessary. It is possible to effectively avoid inconveniences such as the occurrence of dew condensation due to this, and inconveniences such as insufficient cooling.

  Further, in this embodiment, when the correction for increasing the cooling stop set temperature is performed as described above, the cooling stop set temperature exceeds the initial cooling stop set temperature (+ 27 ° C. in this embodiment) by the correction width. Since the upper limit temperature of the corrected cooling stop set temperature is set to the initial cooling stop set temperature, it is possible to avoid the disadvantage that the internal temperature becomes higher than the set temperature.

  In this embodiment, in the cooling stop set temperature correction mode, when correction for lowering the cooling stop set temperature is performed based on the inside temperature, the temperature in the storage chamber 4 at the time when the restart prohibition time has elapsed is set. The correction width is determined based on the difference T1 between the cooling start set temperature and the elapsed time t1 until the temperature in the storage chamber 4 rises from the cooling stop set temperature to the cooling start set temperature. The correction range may be determined based on either the difference T1 or the elapsed time t1.

  Similarly, in the cooling stop set temperature correction mode, when the correction for increasing the cooling stop set temperature is performed based on the internal temperature, the cooling start set temperature and the storage chamber 4 at the time when the restart prohibition time has elapsed. The correction width is determined on the basis of the difference T2 from the internal temperature and the elapsed time t2 from when the temperature in the storage chamber 4 rises to the cooling start set temperature after the restart prohibition time has elapsed. However, the correction width may be determined based on either the difference T2 or the elapsed time t2.

  On the other hand, the control device 40 may execute an air volume control mode as described in detail below, instead of the cooling stop set temperature correction mode as described above in detail.

  This air volume control mode is executed when the amount of heat generated by the server 2 as the heating element housed in the storage room 4 is large. First, the control device 40 determines the tendency of the internal temperature to decrease and the condenser. The amount of heat generated in the storage chamber 4 is estimated from the relationship with the outlet temperature.

  Specifically, heat is generated from the relationship between the temperature T at which the temperature in the storage chamber 4 detected by the internal temperature sensor 33 decreases per minute and the condenser outlet temperature C detected by the condenser outlet temperature sensor 33. Estimate the amount. FIG. 11 shows a table for estimating the amount of heat generation from the relationship between the tendency of the internal temperature to decrease and the condenser outlet temperature as one embodiment.

  According to this, when the temperature T in the lowered chamber per minute is 1 ° C. (when the cooling load is large) and the condenser outlet temperature C is + 30 ° C., the condenser outlet temperature C is relatively low. Nevertheless, it is determined that the cooling efficiency is poor (substantial cooling load is large), and it is estimated that the amount of heat generated by the heating element in the storage chamber 4 is large (2000 W in this embodiment). Similarly, even if the temperature in the lowered chamber T per minute is 1 ° C. (when the cooling load is large), if the condenser outlet temperature C is + 40 ° C., the outside air temperature is the cooling efficiency in the storage chamber 4. Therefore, it is estimated that the amount of heat generated by the heating element in the storage chamber 4 is relatively small (1000 W in this embodiment).

  In addition, when the temperature T in the lowered chamber per minute is 3 ° C. (when the cooling load is small) and the condenser outlet temperature C is + 30 ° C., the condenser outlet temperature C is relatively low, and cooling Since the efficiency is relatively good (substantial cooling load is small), it is estimated that the amount of heat generated by the heating element in the storage chamber 4 is small (1000 W in this embodiment).

  Therefore, it is presumed that the heat generation amount is smaller as the tendency of lowering the internal temperature is larger and as the condenser outlet temperature C is higher, that is, as the cooling load is smaller. In this embodiment, the calorific value is estimated based on the condenser outlet temperature C. However, the present invention is not limited to this, and the calorific value may be estimated based on an outside air temperature sensor that detects the outside air temperature. Be good.

  In the present embodiment, when the heat generation amount estimated as described above is, for example, 1000 W or more, the air flow control mode is executed on the assumption that the heat generation amount by the server 2 as the heat generator in the storage chamber 4 is large. Hereinafter, the air volume control mode will be described in detail with reference to FIGS. 12 and 13. FIG. 12 is a diagram showing a temperature change in the air volume control mode, and FIG. 13 is a flowchart of cooling control.

  First, in step S1, the control device 40 determines whether or not the temperature detected by the internal temperature sensor 32 is higher than the cooling start set temperature. In this embodiment, since the internal temperature is set to + 30 ° C., the cooling start set temperature is assumed to be + 33 ° C. In the present embodiment, it is determined whether or not the temperature is higher than the cooling start set temperature. However, the present invention is not limited to this, and the temperature may be equal to or higher than the cooling start set temperature.

  If the temperature detected by the internal temperature sensor 32 is higher than the cooling start set temperature + 33 ° C. (may be the above case), the process proceeds to step S2, and if it is + 33 ° C. or lower (lower). In this case, the process returns to step S1.

  In step S2, the control device 40 operates the compressor 22 and sets the rotation speed of the cool air circulation fan 17 disposed in the vicinity of the evaporator 16 to the maximum, assuming that the internal temperature rises to the cooling start set temperature, Control with a large circulating air volume (initial circulating air volume) is executed. And it progresses to step S3 and the control apparatus 40 judges whether the internal temperature is lower than cooling stop setting temperature. In this embodiment, since the internal temperature is targeted at + 30 ° C., the cooling stop set temperature is assumed to be + 27 ° C. In the present embodiment, it is determined whether or not the temperature is lower than the cooling stop set temperature. However, the present invention is not limited to this.

  When the temperature detected by the internal temperature sensor 32 is lower than the cooling stop set temperature + 27 ° C. (may be the following case), the process proceeds to step S4, and when it is + 27 ° C. or higher (higher) In this case, the process returns to step S1.

  In step S <b> 4, the control device 40 operates by reducing the number of rotations of the cool air circulation fan 17 while operating the compressor 22, assuming that the internal temperature has decreased to the cooling stop set temperature. In the present embodiment, the total air volume in the fixed period is reduced by lowering the rotational speed of the cool air circulation fan 17, but the present invention is not limited to this, and the total air volume by the cool air circulation fan 17 is reduced. For example, the total air volume may be reduced by performing intermittent operation.

  As a result, the amount of cold air circulated into the storage chamber 4 by the cold air circulation fan 17 decreases, and the internal temperature begins to rise again (see FIG. 12). On the other hand, when the amount of air flowing through the evaporator 16 decreases, the air temperature in the vicinity of the evaporator 16 further decreases, and cold energy is accumulated.

  The control device 40 controls the opening degree of the electronic expansion valve 28 to reduce the evaporation temperature in the evaporator 16 when the control for reducing the circulation air volume by the cold air circulation fan 17 is being executed. The cool storage effect in the evaporator 16 may be improved to improve the cooling efficiency.

  Thereafter, the control device 40 proceeds to step S5 and determines whether or not the evaporator temperature, that is, the refrigerant evaporation temperature in the evaporator 16, in fact, the temperature detected by the evaporator inlet temperature sensor 31 is lower than + 1 ° C. Judging. Further, based on the temperatures detected by the evaporator inlet temperature sensor 31 and the evaporator outlet temperature sensor 32, the difference between the evaporator inlet temperature, that is, the refrigerant evaporation temperature in the evaporator 16 and the evaporator outlet temperature is calculated. Thus, the degree of superheat is acquired, and in this embodiment, it is determined whether or not the degree of superheat is smaller than 5 deg.

  When the temperature of the evaporator 16 is + 1 ° C. or higher and the superheat degree is 5 deg or higher, the process proceeds to step S6, and the control device 40 determines that the internal temperature detected by the internal temperature sensor 32 is the cooling start set temperature. It is determined whether the temperature is higher than (+ 33 ° C. in this embodiment). That is, when the internal temperature is equal to or lower than the cooling start set temperature, the process returns to step S5, and the compressor 22 is continuously operated, and the operation with the number of rotations of the cold air circulation fan 17 being reduced is performed.

  And the operation | movement in the state which reduced the rotation speed by the cold air circulation fan 17 is performed, and the internal temperature gradually rises, and when it rises to the cooling start set temperature, the control device 40 returns to step S2. While the compressor 22 is continuously operated, the operation is performed with the rotation speed of the cold air circulation fan 17 as the original maximum rotation speed (initial circulation air volume).

  As a result, when the amount of heat generated by the server 2 serving as a heating element stored in the storage chamber 4 is equal to or greater than a predetermined value, the compressor even if the air temperature in the storage chamber 4 falls to the cooling stop set temperature. The air flow control mode for reducing the circulating air volume in the storage chamber 4 by the cold air circulation fan 17 from the initial circulation air volume is executed without stopping the operation of the air circulation fan 17, and then the cool air circulation fan 17 is lowered to the cooling stop set temperature. By reducing the amount of circulating air in the storage chamber 4 due to the above, it is possible to avoid the temperature in the storage chamber 4 being lower than the cooling stop set temperature without stopping the compressor 22.

  Therefore, when the compressor 22 is stopped, in order to protect the compressor 22, the air temperature in the storage chamber 4 reaches the cooling start set temperature until a predetermined restart prohibition time elapses. Even so, the compressor 22 cannot be restarted. However, by executing the air volume control mode, the circulating air volume in the storage chamber 4 is reduced without stopping the compressor 22. Thus, it is possible to avoid that the air temperature in the storage chamber 4 falls below the cooling stop set temperature.

  In the above case, the control device 40 reduces the circulating air volume in the storage chamber 4 by the cool air circulation fan 17 when the air temperature in the storage chamber 4 rises to the cooling start set temperature after reducing the circulating air volume. By returning to the initial circulation air volume, it becomes possible to circulate the air stored in the evaporator 16 in the storage chamber 4 when the circulation air volume is reduced, and effectively cool the storage chamber 4. Is possible.

  Therefore, when the heat generation amount of the server 2 as the heating element is equal to or greater than a predetermined value, by executing the air volume control mode, the time required for elapse of the restart prohibition time of the compressor 22, for example, Even when the air temperature in the storage chamber 4 is higher than the cooling start set temperature, the cooling air in the storage chamber 4 can be appropriately controlled by controlling the circulating air volume in the storage chamber 4 by the cool air circulation fan 17. Can be done.

  As a result, there is no need to wait for the restart prohibition time of the compressor 22 even though the air temperature in the storage chamber 4 has reached the cooling start set temperature, and the temperature in the storage chamber 4 rises remarkably. As a result, it is possible to suppress or avoid inconveniences that adversely affect the server 2 as a heating element housed inside.

  On the other hand, when the temperature of the evaporator 16 is lower than a predetermined lower limit value, for example, + 1 ° C. and the superheat degree is lower than the predetermined lower limit value, for example, 5 deg, in step S5, the process proceeds to step S7. 40 stops the operation of the compressor 22, sets the rotation speed of the cool air circulation fan 17 to the maximum (initial circulation air volume), and then returns to step S1. When the control for reducing the rotation speed of the cold air circulation fan 17 is being performed, the valve opening degree of the electronic expansion valve 28 is adjusted as described above, and control is performed to lower the evaporation temperature of the refrigerant in the evaporator 16. If yes, in step S7, the initial valve opening is returned.

  As a result, the control device 40 decreases the number of rotations of the cool air circulation fan 17 to reduce the circulating air volume, and before the air temperature in the storage chamber 4 rises to the cooling start set temperature, the evaporator 16 When the evaporating temperature of the refrigerant is lowered to a predetermined lower limit temperature, or when the degree of superheat in the evaporator 16 is lowered to a predetermined lower limit value, the operation of the compressor 22 is stopped and the inside of the storage chamber 4 by the cold air circulation fan 17 is stopped. Since the circulating air volume of the refrigerant is returned to the initial circulating air volume, the evaporation temperature of the refrigerant in the evaporator 16 is lowered to a predetermined lower limit temperature, and the liquid return to the compressor 22 and the occurrence of dew condensation caused by the reduction of the cooling load are caused in advance. It is possible to avoid it.

  Even when the operation of the compressor 22 is stopped, when the circulating air volume is reduced by returning the circulating air volume in the storage chamber 4 to the initial circulating air volume by the cool air circulating fan 17, the evaporator 16. It becomes possible to circulate the air stored cold in the storage chamber 4. Therefore, when the operation of the compressor 22 is stopped, the compressor 22 can only be restarted after the restart prohibition time has elapsed. The temperature rise time can be delayed, and effective cooling of the storage chamber 4 can be realized.

  In this embodiment, when the evaporator temperature and the superheat degree are equal to or higher than the predetermined lower limit value, the process proceeds to step S6. When the evaporator temperature and the superheat degree are lower (smaller) than the predetermined lower limit value, the process proceeds to step S7. Instead, if the evaporator temperature and the superheat degree are larger (higher) than the predetermined lower limit value, the process may proceed to step S6, and if less than the predetermined lower limit value, the process may proceed to step S7.

  As described above, the air volume control mode is performed in advance by the control device 40 based on the rate of change of the air temperature in the storage chamber 4 and / or the condenser outlet temperature (or outside air temperature). Since the heat generation amount of the server 2 as a body is estimated, the rate of change of the air temperature in the storage chamber 4 and / or without specifically measuring the heat generation amount of the server 2 stored in the storage chamber 4 and / or Since the heat generation amount of the server 2 is estimated based on the condenser outlet temperature (outside air temperature) and the heat generation amount is equal to or greater than a predetermined amount, appropriate cooling control can be realized.

  In the present embodiment, the control device 40 alternately executes the cooling stop set temperature correction mode and the air volume control mode as described above. Thus, by executing the cooling stop set temperature correction mode, it is possible to reduce the number of start-stop times of the cool air circulation fan 17 as compared with the case where the air volume control mode is executed every time, and the air volume control mode. By executing this, it is possible to reduce the number of start-stops of the compressor 22 as compared with the case where the cooling stop set temperature correction mode is executed each time.

  Therefore, by alternately executing these modes, it is possible to adjust the number of start-stops of the compressor 22 and the cold air circulation fan 17, and the inconvenience that the air temperature in the storage chamber 4 rises to the cooling start set temperature. It is possible to improve the durability of the compressor 22 and the cold air circulation fan 17 while suppressing the above.

  In addition, the combination for executing each mode is not limited to the above-described one that is alternately performed, and the amount of heat generated by the server 2 as a heating element in the storage chamber 4 and the cooling performance of the cooling control in each mode. It is preferable to select each mode while maintaining a balance with the above. For example, on the basis of the estimated heat generation amount of the server 2 as the heat generating body accommodated in the storage chamber 4, when the estimated heat generation amount is medium, for example, 1000 W to 1500 W, etc., the air volume control mode is executed. For example, when it is 2000 W or more, the cooling stop set temperature correction mode may be executed.

  This also makes it possible to adjust the number of start-stops of the compressor 22 and the cold air circulation fan 17, while suppressing the disadvantage that the air temperature in the storage chamber 4 rises to the cooling start set temperature. It is possible to improve the durability of the cold air circulation fan 17.

It is a front view of the cooling device to which this invention is applied. It is a vertical side view of a cooling device. It is explanatory drawing of the flow of the cold air of a cooling device. It is a refrigerant circuit figure of a cooling device. It is an electrical block diagram of a cooling device. It is a figure which shows the chamber internal temperature change at the time of the heat generation load increase of the heat generating body of a cooling device. It is a figure explaining the method of determining the fall width of correction | amendment cooling stop preset temperature. It is a table | surface as an example for determining the correction temperature which lowers cooling stop setting temperature. It is a figure explaining the method of determining the raise range of correction | amendment cooling stop setting temperature. It is a table | surface as an example for determining the correction temperature which raises cooling stop preset temperature. It is a table | surface as an example for estimating the emitted-heat amount. It is a figure which shows the change of the internal temperature in an air volume control mode. It is a control flowchart figure in an air volume control mode. It is a figure which shows the change of the internal temperature of the normal time of the conventional cooling device. It is a figure which shows the change of the internal temperature at the time of the heat generation load increase of the heat generating body accommodated in the conventional cooling device.

Explanation of symbols

R Cooling unit 1 Cooling device 2 Server (heating element)
2A Blower 3 Cabinet 4 Storage room 5 Front door 6 Rear door 9 Machine room 11 Cold air inlet (cabinet side)
12 Cold air outlet (cabinet side)
14 Cooling box 15 Cooling chamber 16 Evaporator 17 Cooling air circulation fan 18 Cooling air inlet (cooling box side)
19 Cold air outlet (cooling box side)
22 Compressor 23 Condenser 24 Condenser Blower 28 Electronic Expansion Valve (Expansion Valve)
30 Evaporator inlet temperature sensor 31 Evaporator outlet temperature sensor 32 Inside temperature sensor 33 Condenser outlet temperature sensor 40 Control device

Claims (9)

A storage chamber for storing a heating element, and a cooling unit having a refrigerant circuit composed of a compressor, a condenser, a decompression device, an evaporator, and the like, and cool air exchanged with the evaporator is circulated into the storage chamber by a blower A cooling device for cooling the heating element,
A control device for controlling the operation of the compressor based on the air temperature in the storage chamber;
The control device starts operation of the compressor when the air temperature in the storage chamber rises to a predetermined cooling start set temperature, and when the air temperature in the storage chamber falls to a predetermined cooling stop set temperature. Stopping the operation of the compressor, and having a predetermined restart prohibition time after the compressor stops, and after the stop of the compressor, before the restart prohibition time elapses, When the air temperature rises to the cooling start set temperature, the cooling apparatus is configured to execute a cooling stop set temperature correction mode for correcting the cooling stop set temperature to be lower than the initial cooling stop set temperature.   When the control device performs correction to lower the cooling stop set temperature, the difference T1 between the temperature in the storage room and the cooling start set temperature at the time when the restart prohibition time has elapsed, and / or the storage. Based on the elapsed time t1 until the room temperature rises from the cooling stop set temperature to the cooling start set temperature, the lowering of the cooling stop set temperature is increased as the difference T1 is larger, and the elapsed time t1 is longer. The cooling device according to claim 1, wherein the lowering amount is determined in a direction of decreasing the lowering amount of the cooling stop set temperature.   After performing the correction to lower the cooling set temperature, the control device, if the air temperature in the storage chamber does not rise to the cooling start set temperature even after the restart prohibition time has elapsed from the stop of the compressor, The cooling device according to claim 1, wherein correction for increasing the cooling stop set temperature is performed.   When the control device performs correction to increase the cooling stop set temperature, the difference T2 between the cooling start set temperature and the temperature in the storage room at the time when the restart prohibition time has elapsed, and / or the storage. Based on the elapsed time t2 from when the room temperature has risen to the cooling start set temperature after the restart prohibition time has elapsed, the amount of increase in the cooling stop set temperature is increased as the difference T2 increases. 4. The cooling device according to claim 3, wherein the increase width is determined in a direction of decreasing the increase width of the cooling stop set temperature as t2 is shorter. A storage chamber for storing a heating element, and a cooling unit having a refrigerant circuit composed of a compressor, a condenser, a decompression device, an evaporator, and the like, and cool air exchanged with the evaporator is circulated into the storage chamber by a blower A cooling device for cooling the heating element,
A control device for controlling the operation of the compressor and the blower based on the air temperature in the storage chamber;
The control device starts operation of the compressor when the air temperature in the storage chamber rises to a predetermined cooling start set temperature, and when the air temperature in the storage chamber falls to a predetermined cooling stop set temperature. While stopping the operation of the compressor,
When the heat generation amount of the heating element is equal to or greater than a predetermined value, the operation of the compressor is not stopped even if the air temperature in the storage chamber falls to the cooling stop set temperature, and the storage chamber by the blower is stopped. A cooling device that executes an air volume control mode for reducing the circulating air volume of the air from the initial circulating air volume.   The cooling device according to claim 5, wherein the control device estimates a heat generation amount of the heating element based on a change rate of an air temperature in the storage chamber and / or an outside air temperature.   The controller, after reducing the circulating air volume, returns the circulating air volume in the storage chamber by the blower to the initial circulating air volume when the air temperature in the storage chamber rises to the cooling start set temperature. The cooling device according to claim 5 or 6.   After the controller reduces the circulating air volume, and before the air temperature in the storage chamber rises to the cooling start set temperature, the refrigerant evaporation temperature in the evaporator decreases to a predetermined lower limit temperature, The cooling device according to any one of claims 5 to 7, wherein the operation of the compressor is stopped, and the circulating air volume in the storage chamber by the blower is returned to the initial circulating air volume.   The said control apparatus performs combining the said cooling stop setting temperature correction mode in any one of Claim 1 thru | or 4, and the said air volume control mode in any one of Claim 5 thru | or 8. A cooling device characterized.

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