TWI375002B - - Google Patents

Description

1375002 IX. Description of the Invention [Technical Field] The present invention relates to a cooling storage tank having a plurality of evaporators for supplying refrigerant to these evaporators by one compressor. [Prior Art]

As such a cooling storage, there is a case where, for example, a freezer compartment and a refrigerating compartment are formed in a heat insulating compartment body heat insulating zone, and evaporators are respectively disposed in the respective chambers, and one evaporator is used for each of these evaporators. A cooling storage in which a refrigerant is alternately supplied to a refrigerant to generate a cooling effect is disclosed in Patent Document 1 below.

In the refrigerating cycle of the refrigerator, the refrigerant is compressed by a compressor, and liquefied by a condenser, and alternately supplied thereto, and the evaporator for the freezer compartment and the refrigerating compartment for evaporation at the outlet side of the three-way valve are respectively connected via a capillary tube. When both the freezing compartment and the refrigerating compartment are cooled to the lower limit set temperature, the compressor is stopped, and when either of them exceeds the upper and lower set temperatures, the compressor is restarted. However, in the case of a business refrigerator, in order to frequently open and close the door, or to be in a situation where the ambient temperature is high, it is necessary to assume that the temperature in the library rises sharply during the stop of the compressor. And design. Therefore, in such a refrigerator, if the compressor is stopped, it is necessary to eliminate the high and low pressure difference between the suction side and the discharge side of the compressor as much as possible (when the compressor is restarted in a state where the pressure difference is large, there is The excessive load is applied to the compressor. Therefore, the -3 - 1375002 - the above-mentioned three-way valve is actuated, and the inlet side and the condenser side of the two evaporators for the freezing compartment and the refrigerating compartment are in communication with each other. The refrigerant remaining on one of the refrigerants also flows into the other side, and the high and low pressure difference is quickly eliminated. However, as described above, when the compressor is just stopped, the two evaporators are brought into a communication state to eliminate the high and low pressure difference. For example, when the ambient temperature is low in winter, the refrigerator compartment side becomes supercooled. The problem arises. The reason is as follows: For example, when the set temperature of the refrigerating compartment is set to 3 ° C and the set temperature of the freezer compartment is set to -20 ° C, when the ambient temperature forms a low temperature of about 5 ° C, the refrigerating compartment is Since the temperature difference outside is extremely small, it is almost unnecessary to cool the refrigerator compartment, and the compressor repeats the operation and stops the operation only for cooling the cooling chamber. In other words, when the freezing chamber is at or above the set temperature, the compressor is started, and the refrigerant is supplied to the freezer evaporator, and as a result, when the freezing chamber is cooled to the set temperature or lower, the compressor is stopped. And the three-way valve for balancing the compressed high and low pressure difference connects the two evaporators. Then, when the freezer compartment is again at the set temperature or higher, the compressor is restarted, the three-way valve is switched, and the refrigerant is supplied to the freezer evaporator. During this cooling operation, during the compressor operation, the three-way valve cannot be switched to supply the refrigerant to the evaporator for the refrigerating compartment', but the pressure balance after the compressor is stopped, and the three-way valve is switched to the communication state of the two evaporators, and is supplied. The liquid refrigerant in the evaporator for the freezer compartment is supplied to the evaporator for the refrigerating compartment through the three-way valve. Therefore, the liquid refrigerant becomes a cooling effect as it gradually evaporates for the elimination of the pressure balance. When the refrigerating chamber becomes a set temperature or higher -6 - 1375002, when the compressor is restarted, it also evaporates to form a cooling action. As described above, in the conventional refrigerator-freezer, even if the refrigerant is not supplied to the refrigerator compartment evaporator during the compressor operation, the refrigerator compartment is excessively cooled. The present invention has been made in order to solve the above-mentioned problems, and an object of the invention is to selectively supply a cooling storage of a refrigerant to a plurality of evaporators by one compressor, thereby preventing one of the evaporator sides from being excessively cooled.

SUMMARY OF THE INVENTION The cooling storage of the present invention has the following structure: a refrigeration cycle having the following frustrations of (A1) to (A7), a storage body, which is used in the following freezing compartment The refrigerator uses a cold air generated by an evaporator to cool the interior; a heat load detecting device for detecting a thermal negative Φ state of the refrigeration cycle; and a valve drive circuit for driving and controlling the valve device The valve drive circuit causes the valve device to perform the selective communication operation during the refrigerating cycle operation, and alternately supplies the refrigerant to the evaporator for the freezer compartment and the refrigerating compartment, and when the refrigerating cycle is stopped When the thermal load detecting device detects a thermal load exceeding a predetermined enthalpy, the valve device performs the following common communication operation, and the thermal load detecting device detects the thermal load below a predetermined enthalpy, and causes the valve to be The device performs the following selective communication operation - Ι3750Θ2 (A1) compressor for compressing the refrigerant, (A2) the refrigerant dispersed by the compressor. The condenser and the inlet (A3) are connected to the condenser side, and the two outlets are connected to the first and second refrigerant supply paths, and the inlet side is selectively connected to the first and second refrigerant supply paths. And a selective communication operation of the flow switching operation of any one of the first and second refrigerant supply paths; and the valve device (A4) that is connected to the common communication operation of the first and second refrigerant supply paths; The evaporator for the freezer compartment and the refrigerator compartment of the second refrigerant supply path, and the throttle device (A6) for restricting the refrigerant flowing into the evaporators (A5) have a stop valve and are commonly connected to the freezer compartment. And a refrigerant outlet collecting passage on the refrigerant outlet side of the evaporator for the refrigerating compartment, (A7), the downstream side of the stopping valve is branched by the refrigerant outlet collecting passage, and the refrigerant circulating path connected to the refrigerant suction side of the compressor . According to the above configuration, the liquid refrigerant is selectively supplied to the first and second evaporators by the selective communication operation of the valve device when the compressor is operated, and the cooling is performed by the cooling action of the evaporator. Within the library of the library ontology. When the compressor is stopped, the following operation is performed by the valve device, and the high and low pressure difference of the compressor can be eliminated. In other words, when the heat load state of the refrigeration cycle is large, the valve device performs a common communication operation of bringing the first and second refrigerant supply paths into communication after the compressor is stopped. Therefore, even if the thermal load state of the refrigeration cycle is large, and the high and low pressure difference of the compressor immediately after the stop is large, IH is in the equilibrium operation of the pressure flat -8 - 1375002 balance in the two evaporators. , can quickly eliminate high and low pressure difference.

Further, for example, when the ambient temperature in the winter is low, since the heat load state of the refrigeration cycle is small, the valve device performs a selective communication operation in which only the refrigerant supply path of the refrigerant is in a communication state after the compressor is stopped. Thereby, the high and low pressure differences are further balanced. At this time, since only one of the evaporator sides is used, there is a concern that it takes time to perform pressure equalization, but 'when the heat load state of the refrigeration cycle is small, the high and low pressure difference of the compressor immediately after the stop It is also small, so it is possible to perform pressure equalization in a short time, so there is no problem. Further, the heat load detecting device may be configured to include a temperature detector provided on the refrigerant discharge side of the condenser, and the heat load of the refrigeration cycle may be detected based on the refrigerant temperature on the refrigerant discharge side, or may be provided with detection cooling. The ambient temperature sensor of the ambient temperature of the storage reservoir detects the thermal load of the refrigeration cycle based on the ambient temperature. Regardless of the structure, there is an advantage that the temperature sensor can be used to easily detect the thermal load state of the refrigeration cycle. • According to the present invention, it is possible to prevent the evaporator side of one of the evaporators from being excessively cooled, and to quickly perform the compressor, for the cooling reservoir in which the refrigerant is selectively supplied to the plurality of steamers by one compressor. Pressure balance after stopping. [Embodiment] Hereinafter, embodiments of the present invention will be described with reference to Figs. 1 to 6 . In this embodiment, a case of a horizontal (table type) cooling storage * 9 - 10 Ι 3750 Θ 2 library suitable for business use is taken as an example. First, the overall structure will be described based on Fig. 1 . The symbol is a storage body, which is constituted by a horizontally long heat insulating box that is open at the front, and is supported by a four-legged foot 11 provided on the bottom surface. The storage unit main body 10 is partitioned into left and right by the heat insulating partition wall 12 that is attached later, and the left side relatively narrow side is the freezing compartment 13F corresponding to the first storage compartment, and the right side of the storage compartment is equivalent to the second storage compartment. Refrigeration room 13R. Further, in the opening of the front side of the frozen 13F and the refrigerating compartment 13R, an openable and slidable hot spot (not shown) is mounted. A mechanical chamber 14 is provided on the left side portion of the storage container body 10 when viewed from the front. On the deep side of the upper portion of the machine room 14, an evaporator chamber 15 for the heat insulating freezer compartment 13F communicating with the cold chamber 13F is formed, and a duct 15A and an evaporator fan 15B are provided, and below the compression unit 16, It can be placed in and out of the room. Further, on the side of the compartment 13R side of the partition wall 12, the evaporator chamber 18 for the refrigerator compartment 13R is formed by the extension duct 17, and the evaporator fan 18A is provided here. The compressor unit 16 is provided with a compressor 20 that is driven by a motor (not shown) to compress the refrigerant, and a condenser 21 that is connected to the refrigerant discharge side of the compressor, and can be taken out from the machine room 14 and The condenser fan 22 (shown in Fig. 2 only) for carrying out the condenser 21 is also mounted in the machine room 14. As shown in Fig. 2, the outlet side of the condenser 21 is connected to the inlet 24A of the three-way valve 24 as a valve device through a dryer. The three-way valve 24 has an inlet 24A and two outlets 24B and 24C, and each of the outlets 24B and 24C is connected to the first and second refrigerant supply paths 25 F and 2 5 R. The three-way valve 24 is cooled by the wide-range machine. The cold 20 of the machine is cooled to a 1375500 form. The inlet 24A is selectively connected to the first and second refrigerant supply paths 25F, 25R. The flow switching operation of either one of the first and second refrigerant supply paths 25F and 25R is commonly connected to the inlet 24A. The first refrigerant supply path 2 5 F is provided with a throttle device

The capillary 26F on the freezer side; and the evaporator (first evaporator) 27F in the freezer compartment accommodated in the evaporator chamber 15 on the freezer compartment 1 3F side. Further, the second refrigerant supply path 25R is provided with a refrigerator chamber side capillary 26R as a throttle device, and a refrigerator compartment evaporator (second evaporator) 27R housed in the evaporator chamber 18 on the refrigerator compartment 13R side. . The two evaporators 27F and 27R are configured to superimpose the liquid separator 28F, the check valve 29, and the liquid separator 28R in this order, and are connected in common by the refrigerant outlet collecting flow path 30, and the refrigerant ring flow path 31 collects the flow path from the refrigerant outlet. The stop 30 is connected to the suction side of the compressor 20 so as to be branched toward the downstream side of the valve 29. The circulation path of the refrigerant which is returned to the suction side by the discharge side of the compressor 20 described above is a conventional refrigerating cycle 40 which is configured to supply a refrigerant to the two evaporators 27F and 27R by one compressor 20, and can borrow The supply of the liquid refrigerant to the other party is changed by the three-way valve 24. Further, the three-way valve 24 is driven by a valve drive circuit 60' that receives a signal from the controller 50. The controller 50 is a signal given to the F sensor 51F from the temperature of the air detecting the freezing chamber 1 3 F and the R sensor 51 R detecting the temperature of the air in the refrigerating chamber 13R, in the F sensor When the detection temperature of 51F is higher than the opening temperature (TF (ON)) of the freezing compartment 13F or the detection temperature of the R sensor 5 1 R is higher than the opening temperature (TR (ON)) of the refrigerating compartment 13 R, 'starting The compressor 20' controls the three-way valve 24 in a manner to be described later by the valve drive -11 - 1375002.

Further, a liquid refrigerant temperature sensor (hereinafter referred to as a CT sensor) 52 for detecting the temperature of the discharged liquid refrigerant is provided in the tube on the refrigerant discharge side of the condenser 21, and the detection signal is given to the controller. 50. The three-way valve 24 is controlled in a manner to be described later. Further, the signal from the CT sensor 52 is used to detect an overload condition caused by a heat failure caused by the contamination of the condenser 21 or an abnormality of the refrigeration cycle 40 due to other reasons. The control of the compressor 20 and the three-way valve 24 is performed by a CPU (not shown) built in the controller 50. The structure of the control program is as shown in Fig. 3. Next, this control program will be described together with the action of this embodiment. (Cooling start - F R interactive cooling)

When the compressor 20 is started by pressing the power source of the cooling storage, the three-way valve 24 is alternately switched to a state in which the inlet 24A is only in communication with the first refrigerant supply path 25 F side (hereinafter referred to as this state). In the "F side open state" and the state in which the inlet 24A is only in communication with the second refrigerant supply path 25R side (hereinafter referred to as "R side open state") (step S1) - the refrigerator compartment 13R freezer compartment 13F is created. The state of interactive cooling (R chamber F room interactive cooling). In addition, the "F side open state" and the "R side open state" are both "a form of the selective communication operation j" referred to in the present invention. Next, the process proceeds to step S2, based on the sensor 5 from the R. 1 R news

-12- 1375002

No. 'Comparing the temperature of the refrigerating compartment 13R with the preset refrigerating compartment lower limit temperature TR (OFF), and further, in step S3, comparing the temperature of the freezing compartment 1 3 F with the pre-measured freezing based on the signal from the F sensor 51F The lower limit of the chamber is TF (OFF). Since the temperature in the interior of each chamber has not reached the respective lower limit temperatures since the start of the cooling operation, the process returns to step S1' in step S1 to repeat: the three-way valve 24 alternately switches "F-side open state" at regular intervals. The FR is cooled and operated in parallel with the "R side open state". (F cooling only) When the cooling continues, when the internal temperature of the refrigerating compartment 13R is lower than the preset refrigerating compartment lower limit temperature TR (OFF), the process proceeds from step S2 to step S4, and the three-way valve 24 is switched to "F side opening. State", only the freezer compartment 1 3 F is cooled. Then, the process proceeds to step S5, and based on the signal from the R sensor 5 1 R, it is judged whether or not the previously set refrigerator upper limit set temperature TR (ON ) has not been reached. Generally, since the refrigerating compartment 13R is sufficiently cooled after the FR interactive cooling is completed, the process proceeds to the lower side. Step S6' judges the library in the freezing compartment 1 3 F based on the signal from the F sensor 5 1 F. Whether or not the internal temperature has reached the freezing chamber lower limit temperature TF(OFF) set in advance is repeated until steps S4 to S6 are reached until the freezing chamber lower limit temperature TF (OFF) is reached. As a result, only the freezing compartment 13F is concentratedly cooled.

Further, when the temperature of the refrigerating compartment 13R rises during the cooling operation, the process returns to step S1' to start the FR-13- again from step S5.

1375002- The cooling of the refrigerating compartment 13R, which is the intercooling, is also started again, so that the temperature rise of the refrigerating compartment 13R can be quickly suppressed. By this "F cooling only", the freezing compartment 13F is sufficiently cooled, and when the temperature in the interior reaches the freezing compartment lower limit temperature TF (OFF), the flow proceeds from the step S6 to the step S7. (Compressor stop, pressure equalization process) In step S7, the temperature of the liquid refrigerant discharged from the condenser 21 is compared with a predetermined reference temperature cTset (the determination method is described later) based on the signal from the CT sensor 52. When the ambient temperature is low as in winter, the amount of heat leakage from the storage body 10 is small, or the amount of heat dissipation of the condenser 21 can be sufficiently ensured, the heat load state of the refrigeration cycle 40 is very slight, and therefore, The liquid refrigerant temperature becomes lower. On the other hand, when the temperature outside the winter season or the installation location of the freezer is close to a heat source such as a heater, the heat load state of the refrigeration cycle 40 is heavy, and thus the liquid refrigerant tends to have a high temperature. Therefore, in the state in which the heat load of the refrigeration cycle 40 is normal to heavy, "Y" is reached in step S7, the compressor 20 is stopped (step S8), and then the process proceeds to step S9, and the three-way valve 24 performs communication of the inlet 24A. In the "common communication operation" to the first and second refrigerant supply paths 25F and 25R ("RF ON" in step S9), the compressor 20 is prohibited from being restarted during the predetermined forced stop time T elapsed. (Step S 1 0 ). Further, when the heat load state of the refrigeration cycle 40 is lighter than usual - 14-1375002, since the compressor 20 is stopped by "N" in step S7 (step S11), the process proceeds to step S12, and the three-way valve 24 is performed. The "selective communication operation" is performed (here, the inlet 24A is only connected to the "F-side open state j" of the first refrigerant supply path 2 5 F, and the compressor 20 is prohibited from passing the predetermined forced stop time T. The state of restarting is prohibited during the period (step S 1 0 ).

During the forced stop time T elapsed, the liquid refrigerant is supplied to the freezing chamber cooler 2 7F and evaporated, and the pin is removed from the high and low pressure difference of the compressor 20. Here, when the heat load state of the refrigeration cycle 40 is large, the three-way valve 24 performs the refrigerant supply paths 25F and 25R for the two evaporators 27F and 27R for the freezer compartment and the refrigerator compartment after the compressor 20 is stopped. In the case of the "common communication operation" in the connected state, even if the high-low pressure difference of the compressor immediately after the stop of the refrigeration cycle 40 is large, the difference between the high and low pressures of the compressor immediately after the stop is performed is also performed in the two evaporators 27F and 27R. The equalization action of the pressure, therefore, as shown in Fig. 4, the high and low pressure difference can be quickly eliminated. In the case where the heat load state of the refrigerating cycle 40 is small, for example, the three-way valve 24 is in the "F-side open state", and only the refrigerant supply path 25F that communicates with the freezer compartment cooler 27F is passed, and the height of the compressor 20 is high. The balance of pressure differences continues. However, in this case, since the heat load state of the refrigeration cycle 40 is small, as shown in FIG. 5, the high-low pressure difference of the compressor 20 immediately after the stop is small, and therefore, it can be performed in the compressor forced stop time T. The pressure is balanced and there will be no problems. (Restart of Compressor) -15- When the compressor forced stop time T elapses in step s 1 o, the process proceeds to step S13, and the temperature of the freezing compartment 13F is compared based on the signal from the F sensor 51F. The preset freezing chamber upper limit setting temperature TF (ON) is further set, and in step S14, based on the signal from the R sensor 51R, the temperature of the refrigerating chamber 13R is compared with the previously set refrigerating chamber upper limit setting temperature TF (ON). . When the temperature of the freezing compartment 13F or the refrigerating compartment 13R becomes higher than each of the upper and lower set temperatures in any of the steps, the compressor 20 is started (steps S15, 16), and the process proceeds to step S4 or step S17, and the freezing compartment 13F or the refrigerating compartment is started again. 13R cooling. Further, after moving to step S17, after the cooling of the refrigerating compartment 13R is restarted, when the temperature of the freezing compartment 13F rises, it returns to FR cross-cooling (steps S18 to S1), and when the refrigerating compartment 13R is sufficiently cooled. Then, the process moves to "F cooling only" (step S19 to step S4). (Example of time chart) The cooling operation of returning to "F cooling only" by "F cooling only" is performed, and the compressor 20 is turned ON and OFF, and the opening and closing operation of the three-way valve 24 and the freezer compartment are performed. The temperature change of the 13F and the refrigerating compartment 13R is exemplified as shown in FIG. 6. Here, "F" shows the execution of "F cooling only", "F/R" shows the execution of "FR interactive cooling", and "Stop" displays "Compressor stop, pressure equalization processing". (Setting of the reference temperature CTset) As described above, in the case of "IM shrinking machine stop||:, force balance processing J--16-1375002, the three-way valve 24 is made "F side open state" or "common" The communication operation J' is determined by comparing the temperature of the liquid refrigerant discharged from the condenser 21 with the reference temperature CTset. This temperature can be determined as follows.

In the following experiment, when the freezer-refrigerator of the present embodiment is operated at various ambient temperatures, when the "compressor stop and pressure equalization process" is performed in the "F-side open state", the compressor 20 is forced. In the stop time T, whether or not the pressure difference between the high and low pressures allowed by the compressor 20 is reduced, and it is found that the ambient temperature is lowered to the highest allowable high and low pressure difference within the forced stop time T. Then, the temperature of the liquid refrigerant discharged from the condenser 2 1 at the time of the operation at the ambient temperature (actually, the temperature signal from the CT sensor 52) is set as the reference temperature CTset. (Effect of the present embodiment) As described above, according to the present embodiment, when the heat load state of the refrigeration cycle 40 is large (the discharge temperature of the liquid refrigerant from the condenser 21 is high), the three-way valve 24 is at the compressor. After the lapse of 20, the "common communication state j" in which the two evaporators for the freezing compartment and the refrigerating compartment are in communication is performed. Therefore, even if the thermal load state of the refrigerating cycle 40 is large, the compressor 20 immediately after the stop is caused. The case where the pressure difference is large is also because the pressure equalization operation is performed in the two evaporators 27F and 27R, and the high and low pressure difference can be quickly eliminated. Further, since the heat load state of the refrigeration cycle 40 is small, for example, in winter, the compressor 20 is stopped. The three-way valve 24 becomes "F side open -17-1375002-state j, so that the refrigerant does not flow into the refrigerating evaporator 27R, and the freezing chamber 13F does not become excessively cooled. In the side open state, the refrigerating evaporator 27R does not contribute to the pressure equalization, but when the heat load state of the refrigerating cycle 40 is small, the high-low pressure difference of the compressor 20 immediately after the stop is small. Therefore, the pressure equalization can be performed in a short time, and there is no case that the pressure balance is not completed even after the forced stop time T has elapsed. Further, in the present embodiment, when detecting the thermal load state of the refrigeration cycle 40, the liquid refrigerant temperature sensor (CT sensor) for detecting the liquid refrigerant temperature in the tube on the refrigerant discharge side of the condenser 21 is detected. ), because it can also be used to detect the abnormal heat dissipation caused by the contamination of the condenser 21 or the abnormal overload state of the refrigeration cycle 40 due to other reasons, it is extremely economical and reasonable. The present invention is not limited to the above description and the embodiments described with reference to the drawings. For example, the following embodiments are also included in the technical scope of the present invention. (1) In the above embodiment, when detecting the thermal load state of the refrigeration cycle, the temperature of the liquid refrigerant on the discharge side of the condenser 21 is detected by the CT sensor 52. However, the present invention is not limited thereto, and may be as shown in FIG. It is shown that an ambient temperature sensor 55 for detecting the ambient temperature of the cooling reservoir is provided on the suction side of the cooling fan 22 of the condenser 21, and based on this, the heat load of the refrigeration cycle is detected. In the embodiment shown in Fig. 7, only the portion of the ambient temperature sensor 5 is different from the embodiment of Fig. 2, and the rest of the configuration is the same, and the same reference numerals will be given to the same portions. -18- 1375002 (2) Further, when detecting the heat load state of the refrigeration cycle, for example, the discharge side pressure of the compressor 20 in the refrigeration cycle or the temperature of the condenser 21 (temperature of the cooling air) or the like may be detected. Test

(3) In the above embodiment, the cooling storage compartment including the freezing compartment and the refrigerating compartment has been described as an example. However, the present invention is not limited thereto, and is also applicable to a refrigerating double compartment or a freezing compartment having a refrigerating compartment and a defrosting compartment, and having different storage temperatures. The dual-chamber cooling storage tank, that is, can be widely applied to: at least two evaporators are provided, and the refrigerant is supplied to each evaporator by a common compressor. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing an entire embodiment of the present invention. Fig. 2 is a configuration diagram of a refrigeration cycle. Figure 3 is a flow chart showing the cooling action. Fig. 4 is a graph showing changes in pressure of a compressor stop and a pressure equalization process when the heat load state of the refrigeration cycle is high. Fig. 5 is a graph showing changes in pressure of a compressor stop and a pressure equalization process when the heat load state of the refrigeration cycle is low. Fig. 6 is a timing chart showing the cooling operation and the temperature change in the chamber. Fig. 7 is a view showing the configuration of a refrigeration cycle according to a different embodiment of the present invention. [Explanation of main component symbols] 1 〇: Storage unit body 2 〇: Compressor-19- 137-5002 - 21 : Condenser 24: Three-way valve (valve device) 25F, 25R: First and second refrigerant supply paths 26F 26R: Capillary (throttle device) 27F: Freezer evaporator (first evaporator) 27R: Refrigerator for evaporator (second evaporator) 2 9 : Directional valve

3 0 : refrigerant outlet flow path 3 1 : refrigerant circulation path 40 : refrigeration cycle 52 · CT sensor (temperature sensor of load detection device) 5 5 : ambient temperature sensor 6 0 : valve drive circuit

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Claims (1)

1375002 X. Patent Application No. 1 - A type of cooling storage tank, comprising: a refrigeration cycle having the following structures (A1) to (A7); a storage body, which is used in the following freezing compartment The cold room uses the cold air generated by the evaporator to cool the inside of the storage; a heat load detecting device for detecting a heat load state of the refrigeration cycle; and a valve drive circuit for driving and controlling the valve device, In the valve drive circuit, when the refrigeration cycle is being operated, the valve device is caused to perform the selective communication operation, and the refrigerant is alternately supplied to the evaporator for the freezer compartment and the refrigerator compartment, and when the refrigeration cycle is stopped. When the thermal load detecting device detects a thermal load exceeding a predetermined enthalpy, the valve device performs the following common communication operation, and when the thermal load detecting device detects a thermal load of a predetermined value or less, the valve device is caused to perform the valve device. In the following selective communication operation, the inlet side is a compressor that is only connected to the F-side open state (A1) of the first refrigerant supply path side, and (A2) is compressed by the compressor. The heat-dissipating condenser and the (A3) inlet are connected to the condenser side, and the two outlets are connected to the first and second refrigerant supply paths, and the inlet side is selectively connected to the first and second refrigerant supply paths. Selective communication operation of the flow switching operation of any one of the above; and connecting the inlet side to the first and second refrigerant supply paths in common The valve device for the common communication operation of the diameter, -21 - Ι3750Θ2 (A4), is provided in the freezer compartment for the first and second refrigerant supply paths, and the evaporator for the refrigerator compartment, and (A5) for throttling into each of the above The refrigerant throttling device (A6) of the evaporator has a stop valve and commonly connects the refrigerant outlet collecting passage on the refrigerant outlet side of the freezer compartment and the refrigerating compartment evaporator, and (A7) the refrigerant outlet collecting passage The downstream side of the stop valve is branched and connected to the refrigerant circulation path of the refrigerant suction side of the compressor. 2. The cooling storage of the first aspect of the invention, wherein the heat load detecting device includes a temperature sensor provided on a refrigerant discharge port side of the condenser, and detects the temperature of the refrigerant on the refrigerant discharge side. The heat load of the refrigeration cycle. 3. The cooling storage of claim 1, wherein the heat load detecting device includes an ambient temperature sensor for detecting an ambient temperature of the cooling storage, and detecting the heat of the refrigeration cycle based on the ambient temperature load. -twenty two-