KR20070042561A - Cooling box - Google Patents

Abstract

When the temperature Th of the worm head of the sterling freezer 30 exceeds the reference temperature Th1, the control unit 86 of the freezer maximizes the rotation speed of the heat radiating fan 53, and the circulation pump 61. ), The output of the Stirling refrigerator 30 is minimized, and when the temperature Th of the worm head exceeds the limit temperature Th2, the Stirling refrigerator 30 is stopped. Therefore, compared with the case where the sterling refrigerator 30 is stopped immediately when the temperature Th of the worm head exceeds the threshold temperature Th2, the reliability of the refrigerator can be improved.

Cooler, Housing, Cooling Room, Insulated Door, Packing, Shelf, Machine Room

Description

Cooling box {COOLING BOX}

The present invention relates to a refrigerator, and more particularly to a refrigerator having a Stirling refrigerator.

In recent years, the adverse effects of chlorofluorocarbon gas on the global environment have been pointed out, and attention has been paid to the mounting of a sterling refrigerator as a refrigerator without using chlorofluorocarbon gas. In this refrigerator, the space inside the refrigerator is cooled by the cold heat of the cold head of the sterling refrigerator, and the heat of the worm head of the sterling refrigerator is radiated to the outside environment by the radiator (for example, Japan). See Patent Publication No. 2002-221384).

Patent Document 1: Japanese Patent Application Laid-Open No. 2002-221384

In such a refrigerator, when the temperature of the worm head of the Stirling freezer rises for some reason and reaches the limit temperature, it is also considered to stop the Stirling freezer immediately. However, in this control method, the operation of the refrigerator suddenly stops and the reliability of the refrigerator is impaired.

For that reason, the main object of the present invention is to provide a reliable refrigerator.

The refrigerator which concerns on this invention is a refrigerator provided with a sterling freezer, The temperature detecting means which detects the temperature of the worm head of a sterling freezer, and the detection temperature of the temperature detecting means exceeded a predetermined reference temperature, Before stopping, a control means for controlling the temperature rise of the worm head is suppressed.

Preferably, a radiator for receiving heat from the worm head of the Stirling refrigerator through the coolant to radiate heat to an external environment and a radiating fan for facilitating the radiating of the radiator are provided. The airflow rate of the heat radiating fan is maximized as the temperature exceeds the reference temperature. After that, even if a predetermined time elapses, the output of the sterling refrigerator is lowered when the detected temperature of the temperature detecting means does not become lower than the reference temperature.

Further preferably, the apparatus further includes a refrigerant circulation circuit that transmits the heat of the worm head to the external wall surface through the refrigerant to prevent condensation, and the control means includes a refrigerant according to the detection temperature of the temperature detection means exceeding the reference temperature. When the amount of refrigerant circulating in the circulation circuit is maximized, and the detection temperature of the temperature detecting means does not become lower than the reference temperature even after a predetermined time elapses, the output of the sterling refrigerator is lowered.

Also preferably, the radiator receives heat from the worm head of the Stirling refrigerator through the coolant to radiate heat to the outside environment, a radiating fan that promotes radiating heat from the radiator, and the heat of the worm head to the outside wall through the coolant. The refrigerant circulation circuit which transmits and prevents dew condensation is provided, and a control means maximizes the air volume of a heat radiating fan, as the detection temperature of a temperature detection means exceeds the reference temperature, and after that, a predetermined 1st time has passed. When the detection temperature of the islands temperature detecting means does not become lower than the reference temperature, the amount of refrigerant circulating in the refrigerant circulation circuit is maximized, and the detection temperature of the temperature detecting means does not lower than the reference temperature even after the second predetermined time elapses. There is a decrease in the output of the sterling freezer.

Also preferably, the radiator receives heat from the worm head of the Stirling refrigerator through the coolant to radiate heat to the outside environment, a radiating fan that promotes radiating heat from the radiator, and the heat of the worm head to the outside wall through the coolant. The refrigerant circulation circuit which transmits and prevents dew condensation is provided, and the control means maximizes the refrigerant circulation amount of the refrigerant circulation circuit as the detected temperature of the temperature detection means exceeds the reference temperature, and thereafter, the first predetermined time is determined. When the detection temperature of the temperature detection means does not become lower than the reference temperature even after this has elapsed, the air volume of the heat radiating fan is maximized, and the detection temperature of the temperature detection means does not become lower than the reference temperature even after a predetermined second time elapses. There is a decrease in the output of the sterling freezer.

Further preferably, the control means gradually reduces the output of the sterling refrigerator as the detected temperature of the temperature detecting means exceeds the reference temperature.

Further preferably, the control means stops the Stirling refrigerator as the detected temperature of the temperature detecting means exceeds a predetermined limit temperature higher than the reference temperature.

Further preferably, inspection means for inspecting whether or not the temperature detection means is normal is provided as the detected temperature of the temperature detection means exceeds the reference temperature.

In the refrigerator according to the present invention, as the temperature of the worm head of the Stirling refrigerator exceeds the reference temperature, the temperature rise of the worm head is controlled before stopping the Stirling refrigerator. Therefore, the freezer can be prevented from suddenly stopping, and the reliability of the freezer can be improved.

Preferably, the air volume of the heat dissipation fan is maximized as the temperature of the worm head exceeds the reference temperature, and when the temperature of the worm head does not become lower than the reference temperature even after a predetermined time has elapsed, the output of the sterling refrigerator Lowers. In this case, since the temperature of a worm head can be lowered first without raising the temperature inside a high temperature, the reliability of a refrigerator can be improved.

Preferably, the circulating amount of refrigerant in the refrigerant circulation circuit is maximized as the temperature of the worm head exceeds the reference temperature, and thereafter, when the temperature of the worm head does not become lower than the reference temperature even after a predetermined time elapses, the sterling is performed. Lower the output of the freezer. Also in this case, since the temperature of the worm head can be lowered first without raising the internal temperature of the refrigerator, the reliability of the refrigerator can be improved.

Preferably, the air volume of the heat dissipation fan is maximized as the temperature of the worm head exceeds the reference temperature, and if the temperature of the worm head does not become lower than the reference temperature even after the first predetermined time elapses thereafter, the refrigerant is When the amount of refrigerant circulating in the circulation circuit is maximized and the temperature of the worm head does not become lower than the reference temperature even after the second predetermined time elapses, the output of the sterling refrigerator is lowered. Also in this case, since the temperature of the worm head can be lowered first without raising the internal temperature of the refrigerator, the reliability of the refrigerator can be improved.

Preferably, when the temperature of the worm head exceeds the reference temperature, the amount of refrigerant circulating in the refrigerant circulation circuit is maximized, and the temperature of the worm head does not become lower than the reference temperature even after the first predetermined time elapses thereafter. If the air volume of the heat radiating fan is maximized and the temperature of the worm head does not become lower than the reference temperature even after the second predetermined time elapses, the output of the sterling refrigerator is lowered. Also in this case, since the temperature of the worm head can be lowered first without raising the internal temperature of the refrigerator, the reliability of the refrigerator can be improved.

Further preferably, the output of the sterling refrigerator is lowered in stages. In this case, the rise of the internal temperature can be suppressed.

Further, preferably, the Stirling refrigerator is stopped as the temperature of the worm head exceeds a threshold temperature higher than the reference temperature. In this case, failure of the sterling refrigerator can be prevented.

Further preferably, inspection means for inspecting whether or not the temperature detection means is normal is provided as the detected temperature of the temperature detection means exceeds the reference temperature. In this case, malfunction of the refrigerator due to failure of the temperature detecting means can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows the structure of the refrigerator which concerns on one Embodiment of this invention.

FIG. 2 is a block diagram of the piping of the refrigerator shown in FIG.

FIG. 3 is a block diagram showing a configuration of a part related to operation control of the cooler shown in FIG.

4 is a part of a flowchart showing the operation of the control unit shown in FIG.

5 is another part of the flowchart shown in FIG.

[Description of the code]

1: cooler

10: housing

11, 12, 13: cooling chamber

14, 15, 16: insulated door

17: Packing

18: shelf

19: machine room

20: duct

21: cold air outlet

22: cooling fan

30: Sterling Freezer

40: low temperature side refrigerant circulation circuit

41: low temperature side condenser

42: low temperature side evaporator

50, 60: high temperature side refrigerant circulation circuit

51: high temperature side evaporator

52: high temperature side condenser

53: heat dissipation fan

61: circulation pump

62: condensation prevention unit

70: electric heater

80: high temperature sensor

81: cold head temperature sensor

82: worm head temperature sensor

83: inspection unit

84: reference value storage

85: notice lamp

86: control unit

87: timer

1 is a schematic cross-sectional view showing the configuration of a refrigerator 1 according to an embodiment of the present invention, and FIG. 2 is a piping configuration diagram of the refrigerator 1. 1 and 2, the refrigerator 1 is for food preservation and is provided with the housing 10 of a heat insulation structure. Inside the housing 10, cooling chambers 11, 12, 13 partitioned into three stages are provided. The cooling chambers 11, 12, 13 have openings in the front side (left side in FIG. 1) of the housing 10, respectively, and the said openings are closed by the heat insulation doors 14, 15, and 16 which can be opened and closed. The packing 17 of the form which surrounds the opening part of the cooling chamber 11, 12, 13 is attached to the back surface of the heat insulation door 14, 15, 16, respectively. Inside the cooling chambers 11, 12, 13, the shelf 18 suitable for the kind of food to be accommodated is provided suitably.

The cooling system and heat dissipation system which have the sterling refrigerator 30 as a center element are arrange | positioned from the upper surface to the lower surface from the upper surface of the housing | casing 10. As shown in FIG. Moreover, the machine room 19 is provided in the one corner of the upper back surface of the housing | casing 10, and the sterling refrigerator 30 is provided in the machine room 19. As shown in FIG.

A portion of the Stirling Refrigerator 30 forms a cold head when driven. The cold head is provided with a low temperature side condenser 41. In the cooling chamber 13, a low temperature side evaporator 42 is provided. The low temperature side condenser 41 and the low temperature side evaporator 42 are connected via a refrigerant pipe, and the low temperature side refrigerant circulation circuit 40 is constituted by both. The low temperature side refrigerant circulation circuit 40 is filled with a natural refrigerant such as CO ₂ , and heat exchange is performed in the low temperature side evaporator 42 and the low temperature side condenser 41.

Inside the housing 10, a duct 20 for distributing cold air obtained by the low temperature side evaporator 42 to the cooling chambers 11, 12, 13 is provided. The duct 20 has a cold air outlet 21 communicating with the cooling chambers 11, 12, 13 at an appropriate site. Moreover, inside the duct 20, the cooling fan 22 for forcibly sending cold air is provided in the appropriate site | part.

In addition, although not shown in this figure, the duct which collect | recovers air from the cooling chambers 11, 12, 13 is also provided in the housing 10 inside. The duct has a blowout port below the low temperature side evaporator 42 and supplies cooled air to the low temperature side evaporator 42 as shown by the broken arrow in FIG.

The other part of the sterling refrigerator 30 forms a worm head at the time of driving. The worm head is provided with a high temperature side evaporator 51. In addition, the upper surface of the housing 10 is provided with a high temperature side condenser (heat radiator) 52 and a heat radiating fan 53 which radiate heat in an external environment. The high temperature side evaporator 51 and the high temperature side condenser 52 are connected through piping, and the high temperature side refrigerant circulation circuit 50 is comprised by both. The high temperature side refrigerant circulation circuit 50 is sealed with water (including an aqueous solution) or a hydrocarbon-based natural refrigerant, and the refrigerant naturally circulates in the high temperature side refrigerant circulation circuit 50.

On the other hand, the high temperature side evaporator 51 is also connected to the high temperature side refrigerant circulation circuit 60. The high temperature side refrigerant circulation circuit 60 includes a circulation pump 61 for forcibly circulating refrigerant and a condensation preventing unit 62. The circulation pump 61 is a piezoelectric pump, for example. The dew condensation prevention part 62 arrange | positions a part of refrigerant pipe in the opening part of the cooling chambers 11, 12, and 13, and it is the vicinity of the opening part (packing 17 and the housing 10 which are easy to generate condensation). The surrounding area, i.e., the boundary area between the interior and the exterior, is heated by the heat of the refrigerant to prevent condensation. Further, due to manufacturing reasons, a heat transfer heater 70 that generates heat by energization is provided at a condensation occurrence site where the high temperature side refrigerant circulation circuit 60 cannot be disposed.

Next, operation | movement of the refrigerator 1 which consists of the said structure is demonstrated. In the refrigerator 1 which consists of the said structure, when the Stirling refrigerator 30 is driven, the temperature of a cold head will fall. Therefore, the low temperature side condenser 41 is cooled and the refrigerant inside is condensed.

The refrigerant condensed in the low temperature side condenser 41 flows into the low temperature side evaporator 42 through the low temperature side refrigerant circulation circuit 40. The refrigerant flowing into the low temperature side evaporator 42 evaporates with the heat of the airflow passing through the outside of the low temperature side evaporator 42, and lowers the surface temperature of the low temperature side evaporator 42. Therefore, the air passing through the low temperature side evaporator 42 becomes cold, and is blown out from the cold air outlet 21 of the duct 20 to the cooling chambers 11, 12, 13, and the cooling chambers 11, 12, 13. Lower the temperature. Thereafter, the air in the cooling chambers 11, 12, 13 is refluxed to the low temperature side evaporator 42 through a duct not shown.

In addition, the refrigerant evaporated by the low temperature side evaporator 42 returns to the low temperature side condenser 41 through the low temperature side refrigerant circulation circuit 40, and takes heat there and condenses it again. Then, the heat exchange operation described above is repeated.

On the other hand, the heat | fever which generate | occur | produces by the drive of the sterling refrigerator 30, and the heat collect | recovered from the inside by the cold head radiate | heat-dissipates from a worm head as an array. Therefore, the high temperature side evaporator 51 is heated, and the refrigerant inside evaporates.

The refrigerant in the gaseous state generated by the high temperature side evaporator 51 flows into the high temperature side condenser 52 provided above through the high temperature side refrigerant circulation circuit 50. The refrigerant introduced into the high temperature side condenser 52 takes heat away from the outside by the heat radiating fan 53 and is condensed by the airflow introduced into the high temperature side condenser 52. In addition, the refrigerant condensed by the high temperature side condenser 52 returns to the high temperature side evaporator 51 through the high temperature side refrigerant circulation circuit 50, and receives heat there and evaporates again. Then, the heat exchange operation described above is repeated.

In addition, among the refrigerants saturated in the high temperature side evaporator 51, the refrigerant in the liquid phase state is forced to the high temperature side refrigerant circulation circuit 60 by the circulation pump 61 to prevent condensation. 62). Therefore, the vicinity of the opening of the cooling chambers 11, 12, 13 is heated by the heat of the introduced refrigerant. By setting it as such a structure, dew condensation can be prevented by maintaining the temperature of the vicinity of the opening part which is easy to generate condensation more than dew point temperature, without consuming unnecessary power. In addition, the condensation occurrence site | part in which the high temperature side refrigerant | circulation circuit 60 cannot be arrange | positioned can be prevented from condensation by maintaining the temperature above dew point temperature by energizing the heat transfer heater 70. FIG.

3 is a block diagram showing a part related to operation control in the refrigerator 1. In Fig. 3, the cooler 1 includes a high temperature sensor 80, a cold head temperature sensor 81, a warm head temperature sensor 82, an inspection unit 83, a reference value storage unit 84, and a notification lamp. 85 and a controller 86, which includes a timer 87.

The internal temperature sensor 80 is installed, for example, at a predetermined position on the surface of the interior space side of the duct 20, detects the temperature of the interior space, and provides the control unit 86 with a signal indicating the detected value. The cold head temperature sensor 81 is provided in the cold head of the sterling refrigerator 30, detects the temperature of the cold head, and provides the control unit 86 with a signal indicating the detected value. The worm head temperature sensor 82 is installed in the worm head of the Stirling refrigerator 30, detects the temperature Th of the worm head, and provides the control unit 86 with a signal indicating the detected value.

The inspection unit 83 checks whether the worm head temperature sensor 82 is normal, and provides the control unit 86 with a signal indicating the inspection result. The reference value storage section 84 is composed of a read-only memory such as a ROM, and includes a reference temperature of a high internal space, a reference temperature of a cold head, a reference temperature Th1 of a worm head, and a threshold temperature Th2 of a worm head. I remember it.

The notification lamp 85 is installed on the outer surface of the heat insulating door 14, for example, lights up when the refrigerator 1 has failed, and notifies the user of the failure of the refrigerator 1. The control unit 86 is based on various information from the temperature sensors 80 to 82, the inspection unit 83, and the reference value storage unit 84, and includes the sterling refrigerator 10, the heat dissipation fan 53, and the circulation pump 61. And the notification lamp 85.

4 and 5 are flowcharts showing the operation of the control unit 86. The control unit 86 controls the output of the sterling refrigerator 10 so that the detection value of the temperature sensors 80 to 82 becomes the reference value stored in the reference value storage unit 84, and at the same time, the rotation speed of the heat radiating fan 53, i.e. Control the air volume The control unit 86 also controls the output of the circulation pump 61, that is, the circulation amount of the refrigerant of the high temperature side refrigerant circulation circuit 60.

In addition, in step S1, the control unit 86 determines whether or not the temperature Th of the worm head is higher than the reference temperature Th1 stored in the reference value storage unit 84, and when it is not Th> Th1. Step S1 is executed again. When Th> Th1, the process proceeds to step S2. In step S2, the control part 86 makes the inspection part 83 check whether the worm head temperature sensor 82 is normal. The inspection unit 83 checks whether the worm head temperature sensor 82 is normal, and provides the control unit 86 with a signal indicating the inspection result.

In step S3, the control part 86 determines whether the worm head temperature sensor 82 is abnormal based on the signal from the test | inspection part 83, and if the worm head temperature sensor 82 is abnormal, it returns to step S4. The temperature sensor abnormality alarm process, such as lighting of the notification lamp 85, is performed, and when it is not abnormal, it progresses to step S5.

In step S5, the control unit 86 determines whether or not the rotation speed of the heat radiating fan 53 is the maximum. If not, the control unit 86 maximizes the rotation speed of the heat radiating fan 53 in step S6. In the meantime, the process waits for a predetermined time to elapse, and the process proceeds to step S12. The timer 87 is used for measurement of a predetermined time.

In step S8, the control unit 86 determines whether or not the output of the circulation pump 61 is maximum. If not, the control unit 86 maximizes the output of the circulation pump 61 in step S9, and in step S10. Waiting for a predetermined time to elapse, it progresses to step S12, and when the output of the circulation pump 61 is the maximum, the output of the sterling refrigerator 30 is reduced in step S11, and it progresses to step S12. In step S11, the control unit 86 divides the output of the sterling refrigerator 30 into a plurality of times from the present value to the minimum value and gradually lowers it.

In step S12, the control unit 86 determines whether or not the temperature Th of the worm head is higher than the reference temperature Th1 stored in the reference value storage unit 84, and if not Th> Th1, the control unit 86 proceeds to step S1. It returns to, and proceeds to step S13 when Th> Th1. In step S13, the control part 86 determines whether the output of the sterling refrigerator 30 is minimum, and if it is not the minimum, returns to step S8 and, if it is minimum, proceeds to step S14.

In step S14, the control unit 86 determines whether or not the temperature Th of the worm head is higher than the threshold temperature Th2 stored in the reference value storage unit 84, and if not Th> Th2, the control unit 86 proceeds to step S8. The process returns to step S15 when Th> Th1.

The control part 86 performs a warm-head abnormality display process, such as lighting of the notification lamp 85, in step S15, stops the sterling refrigerator 30 in step S16, and returns to step S1.

In this embodiment, when the temperature Th of the worm head exceeds the reference temperature Th1, the rotation speed of the heat radiating fan 53 is maximized, the output of the circulation pump 61 is maximized, and the Stirling refrigerator The output of 30 is minimized and the Stirling refrigerator 30 is stopped when the temperature Th of the worm head exceeds the threshold temperature Th2. Therefore, compared with the case where the sterling refrigerator 30 is stopped immediately when the temperature Th of the worm head exceeds the threshold temperature Th2, the reliability of the refrigerator 1 can be improved.

In addition, in this embodiment, although the output of the circulation pump 61 was maximized after the rotation speed of the heat radiation fan 53 was maximized, on the contrary, after maximizing the output of the circulation pump 61, the heat radiation fan 53 was made. ) Output may be maximized.

The embodiment disclosed this time is illustrative in all respects and should not be considered as limiting. It is intended that the scope of the invention be indicated by the claims rather than the foregoing description, and include all modifications within the meaning and range equivalent to the claims.

Claims (6)

It is a refrigerator provided with the sterling refrigerator 30, Temperature detecting means (82) for detecting a temperature of the worm head of the Stirling refrigerator (30), and Control means for controlling the temperature rise of the worm head to be suppressed before stopping the Stirling refrigerator 30 as the detected temperature Th of the temperature detecting means 82 exceeds a predetermined reference temperature Th1. A chiller having 86. The radiator 42 according to claim 1, wherein the radiator 42 receives heat from a worm head of the Stirling refrigerator 30 through a refrigerant, and radiates heat to an external environment, and Further provided with a heat dissipation fan 53 for promoting heat dissipation of the heat dissipator 42, The control means 86, As the detected temperature Th of the temperature detecting means 82 exceeds the reference temperature Th1, the air volume of the heat radiating fan 53 is maximized (S6), After that, even if a predetermined time elapses, when the detection temperature Th of the temperature detecting means 82 does not become lower than the reference temperature Th1, cooling is performed to lower the output of the Stirling refrigerator 30 (S11). Go. The coolant circulation circuit of claim 1, further comprising a refrigerant circulation circuit (60) for transferring the heat of the worm head to the outer wall through the refrigerant to prevent condensation. The control means 86, As the detected temperature Th of the temperature detecting means 82 exceeds the reference temperature Th1, the refrigerant circulation amount of the refrigerant circulation circuit 60 is maximized (S9), After that, even if a predetermined time elapses, when the detection temperature Th of the temperature detecting means 82 does not become lower than the reference temperature Th1, cooling is performed to lower the output of the Stirling refrigerator 30 (S11). Go. The radiator 42 of claim 1, wherein the radiator 42 receives heat from a worm head of the Stirling refrigerator 30 through a coolant, and radiates heat to an external environment. A heat dissipation fan 53 for promoting heat dissipation of the heat dissipator 42, and Also provided with a refrigerant circulation circuit 60 to transfer the heat of the worm head to the outer wall through the refrigerant, to prevent condensation, The control means 86, As the detected temperature Th of the temperature detecting means 82 exceeds the reference temperature Th1, the air volume of the heat radiating fan 53 is maximized (S6), After that, even when the first predetermined time elapses, when the detection temperature Th of the temperature detecting means 82 does not become lower than the reference temperature Th1, the refrigerant circulation amount of the refrigerant circulation circuit 60 is maximized. (S9), Further, when the detection temperature Th of the temperature detecting means 82 does not become lower than the reference temperature Th1 even after the second predetermined time elapses, the output of the sterling refrigerator 30 is lowered (S11). Cooler. The radiator 42 of claim 1, wherein the radiator 42 receives heat from a worm head of the Stirling refrigerator 30 through a coolant, and radiates heat to an external environment. A heat dissipation fan 53 for promoting heat dissipation of the heat dissipator 42, and Also provided with a refrigerant circulation circuit 60 to transfer the heat of the worm head to the outer wall through the refrigerant, to prevent condensation, The control means 86, As the detected temperature Th of the temperature detecting means 82 exceeds the reference temperature Th1, the refrigerant circulation amount of the refrigerant circulation circuit 60 is maximized (S9), After that, even when the first predetermined time elapses, when the detection temperature Th of the temperature detecting means 82 does not become lower than the reference temperature Th1, the air volume of the heat radiating fan 53 is maximized ( S6), Further, when the detected temperature Th of the temperature detecting means 82 does not become lower than the reference temperature Th1 even after the second predetermined time has elapsed, cooling to lower the output of the Stirling refrigerator 30 (S11). Go. The refrigerator according to claim 1, wherein the control means (86) lowers the output of the Stirling refrigerator (30) stepwise (S11).

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