JPH0652146B2 - Refrigerator operation control method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the operation of a refrigerator, and more specifically, a first cooler using a brine as a cooling medium, and a refrigerant from a refrigeration system as a cooling medium. In a constant temperature and humidity refrigerator including a second cooler and configured to mainly cool the inside of the refrigerator by the first cooler, the inside temperature rises abnormally for some reason during the cooling period by the first cooler. However, the present invention also relates to a refrigerator operation control method capable of immediately lowering the internal cold storage temperature to a set temperature.

Conventional technology and its problems When considering the operation control of a normal refrigerator that uses a refrigerant such as Freon gas, when the temperature inside the refrigerator rises to the upper limit temperature set by the thermostat, the operation of the refrigeration system is started and the inside of the refrigerator is started. When cooling is performed and the temperature inside the refrigerator drops to the lower limit set temperature, the operation of the refrigeration system is stopped. In this case, the smaller the difference between the upper limit set temperature and the lower limit set temperature, the smaller the fluctuation of the internal temperature, which is preferable, but if the difference is set too small, the high pressure side and the low pressure side of the refrigerant While the equilibrium is not restored, the compressor in the refrigeration system is forced to start and stop frequently, which may cause start failure and other failures due to overload. Further, since the starting current is large, there is a drawback that the power consumption increases and the operating cost becomes uneconomical.

For this reason, generally, it is dealt with by providing a relatively large temperature difference of about 5 to 6 ° C. between the upper limit set temperature and the lower limit set temperature in the refrigerator. However, since the freshness and quality of stored items such as fresh foods (hereinafter referred to as "ingredients") stored in the refrigerator change even between upper and lower set temperatures, there is a problem in maintaining the quality.

In addition, moisture inside the refrigerator condenses and freezes on the surface of the cooler, forming frost that grows in layers, but this frost also reduces the heat exchange efficiency between the cooler and the air inside the refrigerator, so periodic removal is required. Requires frost operation. Therefore, defrosting is performed in which hot gas is branched and supplied from the refrigeration system to a cooler, or a heater arranged near the cooler is electrically heated to melt the frost adhering to the cooler. However, during the defrosting operation, heat is dissipated from the heating medium, and heat that enters the refrigerator from the outside causes
The temperature inside the chamber gradually rises (about 10 to 13 ° C). As a result, the freshness and quality of the foodstuffs stored in the refrigerator are more rapidly deteriorated.

Therefore, in order to store fresh foods for a long period of time without freezing, it is generally necessary to control the temperature change in the refrigerator to be small, and at the same time, to prevent water evaporation from foods. A type of refrigerator that uses brine (antifreeze) as a cooling medium is known.
That is, the brine can be cooled to 0 ° C. or lower without being frozen, and has a large heat capacity. Therefore, there is an advantage that the temperature inside the refrigerator can be set to 0 ° C. or lower to suppress the temperature change. However, even such a brine-cooled refrigerator has a drawback that moisture in the refrigerator condenses on the wall surface during use and frost grows in layers to cause poor cooling of the refrigerator. To remove this frost, it is necessary to raise the temperature of the brine or heat it with a heater or the like to melt the frost, but in any case, the temperature inside the refrigerator inevitably rises during defrosting. Cannot be prevented.

As one proposal for suitably solving these drawbacks, there is an invention “an operation control method of a refrigerator” (Japanese Patent Application No. 61-46895) filed by the applicant of the present application. The brine type refrigerator in which the method according to this proposal is used is arranged in the storage, and the first cooler to which the brine from the brine tank is supplied is also arranged in the storage, and the refrigerator is used. A second cooler to which the refrigerant is supplied via the second electromagnetic valve, and a third cooler which is arranged in the brine tank and to which the refrigerant from the refrigerating device is supplied via the first electromagnetic valve. ,
During the defrosting period of the first cooler, the operation of the refrigeration system is continued, and the second electromagnetic valve and the first electromagnetic valve are alternately switched to alternately cool the second cooler and the third cooler. It is characterized by driving. With this method, even if the defrosting operation is performed to remove the frost adhering to the wall surface, the cooling operation is appropriately controlled so that the internal temperature does not rise.

However, while the inside of the refrigerator is being cooled by the first cooler, for example, a large amount of foodstuff that is still kept at a high temperature immediately after being cooked is stored, or the door is left open for a long time in the season when the ambient temperature is high. In that case, the food material already stored and cooled will be affected by the external temperature and will rise in temperature.
Therefore, when the temperature inside the refrigerator rises abnormally, it is necessary to cool the inside of the refrigerator again to the storage temperature in a short time. Therefore, the heat storage amount in the brine is set to be large. Therefore, a large capacity of the brine tank must be ensured, and in order to increase the circulation amount of brine, it is necessary to use a brine circulation pump having a large capacity. Further, the refrigerating capacity of the compressor needs to be relatively large, and there are problems that the device becomes large and power consumption increases due to the plurality of reasons described above.

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned drawbacks, and is proposed in order to solve this problem. Even if the inside temperature of the refrigerator rises abnormally due to various causes during the cooling operation, the refrigerator can be quickly cooled. By providing the means to reduce the internal temperature to the normal storage temperature, effectively prevent the freshness and quality of food materials from deteriorating, and at the same time downsize the device, reduce power consumption. The purpose is to do.

Means for Solving the Problems In order to overcome the above-mentioned problems and to suitably achieve the above-mentioned object, an operation control method for a refrigerator according to the present invention is a storage compartment defined inside a box, A refrigerating apparatus including a compressor and a condenser of a refrigerant, a brine tank for storing brine, a first cooler arranged in the storage and supplied with brine from the brine tank, the storage The refrigerant from the refrigeration system is disposed inside the
A second cooler supplied by opening a second electromagnetic valve that is normally closed, and a second cooler that is disposed in the brine tank and that has a refrigerant from the refrigerating device that is always open. In a refrigerator composed of a third cooler supplied via one solenoid valve, by constantly controlling the cooling operation and the stopping of the cooling operation of the first cooler, the internal cold storage temperature is set to the upper limit set temperature. When the temperature inside the refrigerator is maintained above the lower limit set temperature and is higher than the upper limit set temperature in the refrigerator by a predetermined temperature or more, the cooling operation of the first cooler is stopped and the second solenoid valve is turned on. It is characterized in that the cooling operation of the second cooler is started by opening the valve and supplying the refrigerant to the second cooler.

Further, a refrigerator operation control method according to another invention of the present application, which can preferably achieve the same object, in a refrigerator having the same configuration, always controls the cooling operation and the cooling operation stop of the first cooler. As a result, the temperature inside the refrigerator is maintained between the upper limit setting temperature and the lower limit setting temperature, and when the temperature inside the refrigerator rises above the upper limit setting temperature by a predetermined temperature or more, the cooling of the first cooler is performed. While continuing the operation, the second electromagnetic valve is opened to supply the refrigerant to the second cooler, and the inside of the refrigerator is cooled by both coolers.

[Embodiment] Next, an operation control method for a refrigerator according to the present invention will be described below with reference to the accompanying drawings by exemplifying a brine-cooled constant temperature and humidity refrigerator capable of suitably implementing the operation control method.

(Regarding Schematic Configuration of Refrigerator) FIGS. 1 to 3 schematically show the appearance and internal structure of a constant temperature and humidity refrigerator in which the operation control method according to the present invention can be suitably implemented. In this refrigerator, a box body 1 and a cooling unit section 2 are partitioned, and a top plate 3 is commonly arranged on the upper part. A storage case 1a for cooling and storing foodstuffs is defined inside the box body 1. The opening of the storage case 1a has two doors 4 arranged horizontally.
Opened and closed by 4. Further, a shelf (not shown) on which food materials are placed and the like are detachably provided horizontally inside the storage 1a.

The cooling unit 2 is detachably covered by a cover 5, and when the cover 5 is removed, as shown in FIG. 2, a refrigerating device 6 including a compressor CM, a solenoid valve, a fan motor, a condenser 7, and the like. And a brine cooling unit portion 9 located above the refrigerating apparatus 6 and the inside temperature controller 1
0, a thermometer 11, various components such as an electrical equipment box 13 having an abnormality warning lamp 12 and the like appear.

FIG. 3 shows a cross section of a main part of the constant temperature and humidity refrigerator according to the present embodiment, in which a heat insulating material 16 is filled between an outer box 14 and an inner box 15 which form the box 1. A first cooler 17, to which brine cooled in a brine tank 8 described later is circulated, is disposed on the right side inside the storage box defined in the inner box 15. Further, as shown in the drawing, a cooling duct 18 that is opened downward and is sealed at the upper side is arranged in the refrigerator to cover the first cooler 17 in a non-contact manner.

An opening 19 is formed in the cooling duct 18, and the fan air FM ₁ arranged in the opening 19 allows the inside air sucked from below the cooling duct 18 to move to the first cooler 17.
After being cooled by exchanging heat with
It circulates as shown by the solid line arrow in FIG. 6 to cool the entire inside of the refrigerator. Further, a defrost thermo Th ₁ for detecting the end of defrost and a heater H ₁ for accelerating defrost are provided in the vicinity of the first cooler 17, and water droplets dripped from the cooler 17 during defrost are further collected. The dew tray 21 is arranged below the first cooler 17.

A second cooler 22 to which the refrigerant from the refrigeration system 6 is circulated and supplied is disposed on the left side surface inside the storage. A cooling duct 23, which is open at the lower side and closed at the upper side, is arranged in the refrigerator to cover the second cooler 22 in a non-contact manner. An opening 24 is formed in the cooling duct 23, and the fan motor FM ₂ arranged in the opening 24 circulates the inside air as indicated by the broken line arrow in FIG. 6 to cool the inside of the inside. ing. In the vicinity of the second cooler 22, a defrost thermo Th ₂ for detecting the end of defrost and a heater H ₂ for accelerating defrost are arranged, and a dew tray 26 for collecting water drops dropped during defrost, It is arranged below the cooler 22. In FIG. 6, reference numeral 70 indicates a temperature-sensing portion of the in-compartment thermostat Th ₃ which is arranged at a proper place in the refrigerator.

(Regarding Brine Cooling Unit Section) Details of the brine cooling unit section 9 are shown in FIGS.
Shown in the figure. The brine cooling unit 9 has a function of cooling the brine with the refrigerant from the refrigerating device 6 and circulatingly supplying the brine to the first cooler 17 as a cooling medium. The brine tank 8 arranged in the unit portion 9 is configured as a box-shaped container in which a heat insulating material 32 is filled between an outer box 30 and an inner box 31, and its upper opening portion has an upper lid 34 and an inner lid. It is detachably attached by a lid 33 having a heat insulating material 36 interposed therebetween. Top lid 3
Each of the end edges of 4 is bent at a right angle and fits into the outer box 30 of the tank 8 so that the upper edge 37 of the tank 8 and the inner lid 35 can come into close contact with each other. . The end portion of the upper lid 34 is fixed to the tank outer box 30 via a bolt 38.

At the lower part of the side wall of the inner box 31 in the tank 8, a suction pipe 39
One end of the is communicated with its opening facing the tank,
The other end is connected to the suction pipe 41 of the brine circulation pump PM. Discharge pipe 42 communicating with the discharge side of this pump
Communicates with the supply pipe 67 of the first cooler 17. A discharge pipe 43 that bends in a key shape and opens downward is provided on the upper side wall of the inner box 31 (the upper position of the suction pipe 39), and the other end of the discharge pipe 43 is a return pipe 44 formed of a hose. Connected for communication. The return pipe 44 is connected to the return pipe 68 of the first cooler 17. The discharge pipes 42, 43, the return pipe 44 and the suction pipes 39, 41 are covered with a heat insulating hose 45, respectively.

An L-shaped support plate 48 is fixed to the bottom portion 31a of the tank 8 via bolts 49, and a third cooler 47 (connected to the refrigerating device 6) is wound around the support plate 48 in a coil shape. The brine 46 stored in the tank is cooled to the required temperature. The bolt penetration portion of the bottom portion 31a is sealed by a screw receiver 50 adhered to the back surface of the bottom portion to prevent brine from leaking to the outside.

A brine detection tank 51 having a function of detecting the presence / absence of brine circulation is fixed to a side wall 31b of the inner tank box 31 via a bolt 52, and an intermediate position in the tank 8 (above a predetermined brine storage level). Facing. As shown in FIG. 5, the brine detection tank 51 is configured as a box body having an open upper surface, and a liquid drain hole 53 is formed in the bottom portion 51a thereof. The liquid drain hole 53 is set to have a hole diameter that allows only a very small amount of the brine to flow through the discharge pipe 43 into the detection tank 51. Therefore, a part of the brine supplied from the discharge pipe 43 is partially discharged from the drain hole 53 to the brine tank 8.
Most of the brine flows down to the detection tank 5, although it flows down into the tank.
It is stored in 1. Then, the brine finally overflows from the upper edge portion 51c of the side wall of the detection tank 51 and reaches the brine tank 8.

Further, an L-shaped mounting plate 54 is fixed to the side wall 51b of the brine detection tank 51, and a float switch 55 is mounted on the plate surface protruding from the tank opening. The float switch 55 is provided with a float 55a, and the detection tank 5
When the amount of brine in 1 decreases, the float 55a lowers to turn off the switch. When the brine fills the detection tank 51 and overflows, the float 55a rises to turn on the switch. Instead of the float switch, an electrode switch, a pressure switch or other mechanical switch may be used.

The brine tank 8 is provided with a liquid level gauge 101 based on the principle of a communicating pipe. The liquid level gauge 101 is preferably a transparent synthetic resin tube body that does not deteriorate under low temperature conditions and is flexible. used. The tube stands upright outside the tank, and the fixed piece 102
A cap 104 having a through hole formed therein is fixedly supported by the cap 104. As shown in FIGS. 1 and 2, the cover 5 of the cooling unit 2 is provided with a rectangular observation window 100 through which the liquid level gauge 101 can be visually recognized from the outside when the cover 5 is attached.

(Regarding Refrigeration Circuit and Brine Circulation Circuit) FIG. 6 is a schematic system diagram showing respective pipelines of the refrigerant refrigeration circuit and the brine circulation circuit. In the figure, the refrigerant gas compressed by the compressor CM is liquefied in the condenser 7 which is forcibly cooled by the fan motor FM ₃ and dehumidified in the dryer 62, and then is connected to the conduit on the first solenoid valve V ₁ side. It is branched to the second solenoid valve V ₂ side pipe line. The liquefied refrigerant that has passed through the first solenoid valve V ₁ is decompressed by the capillary tube 63, evaporates in the third cooler 47 arranged in the brine tank 8 and exchanges heat with the brine, and cools the brine. To do. The evaporated vaporized refrigerant returns to the compressor CM via the suction pipe 64.

The liquefied refrigerant that has passed through the second electromagnetic valve V ₂ is decompressed by the capillary tube 65, evaporates in the second cooler 22 and exchanges heat with the air in the cold storage to cool the cold storage. The vaporized refrigerant that has evaporated returns to the compressor CM via the suction pipe 66.
In this case, the second cooler 22 and the third cooler 4
A gas-liquid separator may be provided on the outlet side of the valve 7, and check valves may be provided on the suction pipes 64 and 66, respectively.

Next, in the brine circulation circuit, the brine 46 stored in the brine tank 8 is cooled to a required temperature by the third cooler 47 connected to the refrigerating device 6, and circulates via the suction pipe 39 led out from the tank 8. After being sucked by the pump PM, it is supplied to the first cooler 17 via the discharge pipe 42 and the supply pipe 67. Then, after cooling the first cooler 17 and exchanging heat with the air in the refrigerator, the first cooler 17 is returned from the return pipe 68 to the brine detection tank 51 via the key-shaped discharge pipe 43.

The brine returned to the detection tank 51, as described above,
Some flow down from the return hole 53, and others flow into the detection tank 51.
It overflows from the upper edge portion 51c of the side wall of and is stored in the brine tank 8. When the liquid level in the detection tank 51 rises,
The contact of the float switch 55 is turned on.

(Regarding Electric Control Circuit System) FIG. 7 shows an example of an electric control circuit of a constant temperature and high humidity refrigerator in which the operation control method according to the first invention of the present application is preferably implemented. In this circuit diagram, CM is a compressor, FM ₃ is a condenser fan motor, FM ₂ is a second cooler fan motor, FM ₁ is a first cooler fan motor, V ₁ is a first solenoid valve, V ₂ is a second 2 Solenoid valves and PM are pump motors, respectively.
Further, the internal thermostat Th ₃ has two contact points Th ₃ −a and Th ₃
Has -b, one contact Th ₃ -a is serially connected to the power supply bus R-phase and T-phase through the compressor CM and the fan motor FM ₃ are connected in parallel. The other contact Th ₃ −
The terminal a of b is connected to the R phase of the power source bus, the terminal b is connected to the second solenoid valve V ₂ and the fan motor FM _2, and the terminal c is the first solenoid valve V ₁ , the fan motor FM ₁ and the pump motor. PM
Are connected.

As shown in the timing charts of FIGS. 8 and 9, one contact Th _3- a of the internal thermostat Th ₃ is opened when the detected temperature reaches the lower limit set temperature T ₀ , and the upper limit set temperature is reached.
It is set to close at T ₁ . The other contact Th ₃ -b is closed the contact a-c side when the detected temperature reaches the lower limit set temperature T _0, abnormal set switched becomes the temperature T _2, together with the contacts a-b is closed , The contacts a-c are set to open. Furthermore the contact Th ₃ -b is
The contacts a-b are closed and the contacts a-c are opened during the defrosting operation in the first cooler 17, and the contacts a-c are closed during the defrosting operation in the second cooler 22. The contacts a-b are set to open. The temperature difference t between the upper limit set temperature T ₁ and the abnormal set temperature T ₂ in the refrigerator can be set arbitrarily. Further, it is preferable to set the abnormal set temperature T ₂ to a temperature that affects quality such as freshness of the foodstuffs stored in the refrigerator.

FIG. 12 shows an example of an electric control circuit of a constant temperature and humidity refrigerator in which the operation control method according to the second invention of the present application is preferably implemented, and is basically the same as the electric control circuit of the first invention. . However, c terminal of the contact Th ₃ -b at the internal thermo-Th ₃ is connected only to the first solenoid valve V _1, also the fourth contact Th ₃ -d is provided the internal thermo-Th _3, the contact Th ₃ -d
Is a fan motor FM ₁ and a pump motor P connected in parallel
It is connected to M. As can be seen from FIG. 9, the contact Th ₃ -d is always in the closed state, the fan motor FM ₁ and the pump motor PM are rotated, and the brine is circulated to the first cooler 17. There is. The first cooler 17 is opened during the defrosting operation to stop the rotations of the fan motor FM ₁ and the pump motor PM.

Action of the Embodiment Next, the action of the operation control method according to the present invention when the refrigerator and the electric control circuit according to the above-described configuration are operated will be described.

(From turning on the power to cooling the inside of the refrigerator) Prior to the operation of the device, the cooling unit 2 in the refrigerator
The front cover 5 is removed, the electrical equipment box 13 is pulled out to the front, and the lid 33 of the brine tank 8 is removed to open the tank 8. Next, the brine 46 is injected into the brine tank 8 in an amount that is the sum of the volume of the brine present in the circulation pipe system and the storage amount of the brine at the proper liquid level in the tank 8. After the injection of the brine 46 is completed, the lid 33 is reattached, the electrical equipment box 13 is inserted into a predetermined position, and then the front cover 5 is attached to the cooling unit section 2.

When power is applied for the refrigerator operation, the internal temperature of storage case is kept still to around room temperature, the internal thermo-Th ₃
The temperature sensitive portion 70 detects this, contact Th ₃ of that one
-A is closed. Therefore, the compressor CM and the fan motor FM ₃ are activated to start the operation of the refrigeration system 6.
The other contact Th ₃ -b in the internal thermo-Th _3, since the inside temperature is higher than the abnormal set temperature T ₂ above, its contacts a-b is closed. Therefore, the solenoid (not shown) of the second solenoid valve V ₂ is energized to open the valve via the contacts a-b, and the refrigerant from the refrigeration system is circulated to the second cooler 22.

That is, the refrigerant in the refrigeration system is compressed by the compressor CM and then condensed in the condenser 7 to be liquefied, and the dryer 62, the second
Is depressurized by the capillary tube 65 passes through the solenoid valve V _2, after which a liquid refrigerant flows into the second cooler 22, and air heat-exchanged in the refrigerator becomes vaporized refrigerant evaporates here, inhalation The cycle returning from the pipe 66 to the compressor CM is repeated to cool the second cooler 22. Also contact point Th ₃
The second fan motor FM ₂ is also energized via the contact points a-b in the closed state of -b to start rotation, and the air in the refrigerator is sucked in from below the cooling duct 23 as indicated by the broken line, Two
Cooling of the inside of the refrigerator is started by discharging after heat exchange with the cooler 22.

When the inside of the refrigerator cools down and the temperature drops to the lower limit set temperature T ₀ of the inside thermostat Th ₃ , one contact Th _{3 in} FIG.
-A is released, and the rotations of the compressor CM and the fan motor FM ₃ are stopped. At the same time, the other contact Th ₃ -b is also switched from the contact ab side to the contact ac side, and this contact ab
The second solenoid valve V ₂ is closed by the opening of the fan, the fan motor FM ₂ is stopped, and the cooling by the second cooler 22 is stopped. While the first solenoid valve V ₁ is opened by closing of the contact a-c in contact Th ₃ -b, switched the flow of liquid refrigerant from the refrigeration system 6, the said refrigerant is caused to face in a brine tank 8 3 Head to the cooler 47. That is, the liquefied refrigerant that has passed through the first solenoid valve V ₁ is decompressed by the capillary tube 63, becomes a liquefied refrigerant, and flows into the third cooler 47, where it is evaporated and becomes an evaporated refrigerant to exchange heat with the brine 46. After that, the cycle of returning to the compressor CM via the suction pipe 46 is repeated to cool the third cooler 47.

At the same time when the first solenoid valve V ₁ is opened, the fan motor FM ₁ provided in the first cooler 17 and the pump motor PM provided in the brine tank 8 also rotate. The fan motor FM ₁ has a function of sucking the inside air from below the cooling duct 18 as shown by a solid line, exchanging heat with the first cooler 17, and then discharging the heat. The pump motor PM supplies the brine 46 in the brine tank 8 to the first cooler 17 via the pipe body 67,
The brine 46 passing through the first cooler 17 is returned to the return pipe 68.
And the discharge pipe 43 to return to the brine detection tank 5
It begins to flow down into 1. As described above, the amount of brine flowing out of the drain hole 53 formed on the bottom surface 51a of the brine detection tank 51 is set to be smaller than the amount of brine flowing into the tank 51 from the discharge pipe 43. . Therefore, a part of the inflowing brine flows down from the liquid drain hole 53 into the brine tank 8, and most of it is stored in the brine detection tank 51, and its liquid level gradually rises. Due to this rise in the liquid level, the brine 46 finally overflows from the upper edge portion 51c of the side wall of the detection tank 51, and begins to flow down to the brine tank 8 below. Further, the float 55a of the float switch 55 starts to float as the liquid level in the tank 51 rises, closes internal contacts, and electrically informs that brine is circulated in the first cooler 17. Detect. The float switch 55 is adapted to activate an alarm means (not shown).

The internal temperature of the storage case 1a gradually rises due to the heat entering from the outside through the heat insulating material 16 and the initial heat of the brine 46 discharged from the first cooler 17 into the storage case at the start of the cooling operation, The temperature reaches the upper limit set temperature T ₁ set for the internal thermo Th ₃ . Then contact Th ₃ -a of the internal thermo-Th ₃ is closed, resume the rotation of the compressor CM and the fan motor FM _3. Although the internal temperature further rises from the upper limit set temperature T ₁ , the temperature of the brine 46 that has exchanged heat with the third cooler 47 gradually decreases. The cooled brine 46 is the pump motor PM.
Is supplied to the first cooler 17, where it exchanges heat with the air in the refrigerator to cool the inside. The brine whose temperature has risen due to heat exchange returns from the discharge pipe 43 to the inside of the brine tank 8 via the return pipe 68, exchanges heat with the third cooler 47, is cooled again, and then goes to the first cooler 17. Repeat the circulation cycle. Therefore, the rise in the temperature inside the refrigerator decreases with the lapse of time, and the inside of the refrigerator is finally cooled only by the cooled brine.

Here, if the temperature of the brine at the start of cooling is abnormally high, the internal cold storage temperature rises rapidly and becomes higher than the abnormal set temperature T ₂ . Then, of the internal thermo-Th ₃ contact Th ₃ -b is contact a
Switching to the −b side, the second solenoid valve V ₂ is opened, and the cooling inside the refrigerator by the second cooler 22 is restarted. When the inside of the refrigerator is cooled by the second cooler 22, the first cooler 17 is also cooled, and the brine remaining inside is also cooled, and the temperature is lowered. After that, when the internal temperature reaches the lower limit set temperature T ₀ , the internal thermo Th ₃
One contact Th ₃ -a is opened to stop the operation of the refrigeration device 6.

And by reaching the lower limit set temperature T ₀ of the temperature inside, the other contact Th ₃ -b is switched to the contact a-c side of the internal thermo-Th _3, with opening the first solenoid valve V _1, the pump Motor P
M is rotated again to circulate the brine 46 in the brine circulation system including the first cooler 17. Therefore, the brine 46 is not actively cooled by the third cooler 47 (since the refrigeration system 6 is not operating),
Due to the negative heat storage of the first cooler 17 itself, the low-temperature air circulating in the refrigerator, and the low-temperature brine remaining in the first cooler 17, the temperature gradually decreases.

Incidentally inside temperature reaches the upper limit set temperatures T ₁ again from the lower limit set temperature T _0, thereby the internal contacts Th ₃ thermo Th ₃
-A is closed, the compressor CM and the fan motor FM ₃ restart their rotation, and the third cooler 47 cools the brine 46. Therefore, the internal cold storage temperature does not rise to the abnormal set temperature T ₂ . In this way, when the cycle of cooling the inside of the refrigerator by the cooled brine 46 is repeated, the temperature difference between the inside temperature and the first cooler 17 becomes extremely small, and thus the frost formation on the first cooler 17 occurs. The amount decreases and the inside of the refrigerator is kept at high humidity. And the temperature inside the refrigerator is the thermostat inside the refrigerator Th ₃
When the temperature lowers to the lower limit set temperature T ₀ of, the contact Th ₃ -a is opened and the rotation of the compressor CM and the fan motor FM ₃ is stopped. When the operation of the refrigeration system 6 is stopped in this way, the brine is not cooled by the third cooler 47.
However, the amount of brine 46 stored in the brine tank 8 is several times the amount present in the pipeline for circulation, and the brine tank 8 uses the heat insulating material 32 to prevent heat from entering from the outside. Since it is cut off, the cold storage effect is high. Therefore, the brine 46 stored in the brine tank 8 is circulated by the pump motor PM and still continues to cool the first cooler 17.

However, the internal temperature of the storage case 1a depends on various factors such as heat entering from the outside through the heat insulating material 16, heat entering when the door 4 is opened and closed for accommodating and taking out food, and other heat radiation from the food itself. It gradually rises depending on the cause. Further, the first cooler 17 is also warmed by the air inside the refrigerator which is circulated by the fan motor FM ₁ , so that the brine circulating in the cooler 17 is also gradually warmed and the temperature of the brine in the brine tank 8 is gradually increased. Start climbing. When the internal temperature reaches the upper limit set temperature T ₁ of the internal thermo Th ₃ , the thermo Th ₃
Contact Th ₃ of -a is closed to resume the operation of the compressor CM and the fan motor FM _3. Therefore, the refrigerant circulates in the third cooler 47, and the cooling of the brine in the tank 8 is restarted.

The brine cooled in the third cooler 47 is used in the first cooler 1
7, the inside of the refrigerator is cooled, and the inside temperature is the lower limit set temperature.
At T ₀ , the contact Th ₃ −a of the internal thermostat Th ₃ opens,
The operation of the refrigeration system 6 is stopped. After that, the inside of the refrigerator is maintained at a constant temperature by repeating this process.

As previously mentioned, from the start of the cooling run to the inside temperature reaches the lower set temperature T ₀ of the internal thermo-Th _3, the second cooler 22
The inside of the refrigerator is cooled by the first cooler 17 so as to maintain the inside temperature between the upper limit set temperature T ₁ and the lower limit set temperature T ₀ of the inside thermostat Th _3. It

By the way, in the second cooler 22, the refrigerant in the refrigerating system is evaporated, and the evaporation temperature of this refrigerant is much lower than the internal temperature. Therefore, the temperature difference between the surface temperature of the second cooler 22 and the inside temperature is extremely large, and when heat is exchanged by circulating the inside air by the fan motor FM ₂ , the inside temperature is rapidly lowered. And the second cooler 22
Since the surface temperature of is less than 0 ° C., frost is formed on the surface of the cooler. In addition, it is preferable to set the evaporation temperature of the refrigerant in the second cooler 22 to about −10 ° C. to −15 ° C. and increase the refrigerant circulation amount to enhance the cooling capacity of the second cooler 22. .

Further, in the first cooler 17, a cooled brine having a large specific heat is circulated to cool the inside of the refrigerator, and the temperature difference between the inside temperature and the surface temperature of the first cooler 17 is made small to cool the refrigerator. It is possible to suppress the amount of frost on the surface and keep the internal humidity high. However, the difference between the inside temperature and the temperature of the brine circulating through the first cooler 17 is small, and even if the inside temperature rapidly rises due to some reason, this first
It is difficult for the cooler 17 to lower the internal temperature in a short time. The reason is that the difference TA between the inside temperature and the surface temperature of the first cooler 17 is the difference TB between the inside temperature and the surface temperature of the cooler when the refrigerant is circulated through the second cooler 22. This is due to the fact that it is smaller than the above (TA <TB).

For example, in the timing chart shown in FIG. 8, when the inside of the refrigerator is kept cold by the first cooler 17 within the range of the upper limit set temperature T ₁ and the lower limit set temperature T ₀ of the inside thermostat Th _3. , If the door 4 is opened at the point A and a large amount of food still hot is stored in the refrigerator, or if the door 4 is opened for a long time, the temperature in the refrigerator rapidly rises to the point B. The internal temperature is A
In the process of rising from point to point B, it passes through the upper limit set temperature T ₁ of the storage room thermo Th _3, one contact T in the internal thermo-Th ₃
h ₃ -a is closed, the compressor CM and the fan motor FM ₃ is a brine in the tank 8 to resume the rotation third cooler 47
To cool. The other contact Th ₃ of the thermostat Th ₃ in the refrigerator
In the case of −b, the contacts ac are still closed, so the brine cooled by the third cooler 47 is circulated to the first cooler 17 to start cooling the inside of the refrigerator. Further the inside temperature rises toward the point B, it passes through the abnormal set temperature T _2, the internal thermo-Th ₃
Other contact Th ₃ -b of by switching operation, to close the contact point a-b with opening contacts a-c. By closing the contacts a-b, the second solenoid valve V ₂ is opened and the refrigerant in the refrigeration system is circulated in the second cooler 22. Further, the fan motor FM ₂ also rotates to cool the inside of the refrigerator by the second cooler 22.

The abnormal increase in the temperature inside the chamber is stopped at point B due to the closing of the opened door 4 or the temperature saturation due to the heat radiation of the high temperature foods, and as described above, the inside of the chamber continues to be cooled by the second cooler 22. Therefore, the internal cold storage temperature reaches the lower limit set temperature T ₀ of the internal thermostat Th _{3 in} a short time. As a result, the internal thermo Th ₃
While contact Th ₃ of and -a is opened to stop the operation of the refrigeration device 6, also the other contact Th ₃ -b by switching operation of the contacts a
-B is opened and the contacts ac are closed, and the pump motor PM rotates to circulate the brine in the first cooler 17. In this way, with the abnormal increase in the internal temperature described above, the product temperature of the food already cooled and stored also starts to increase, but according to the present embodiment, the time until returning to the upper limit set temperature T ₁ is short. Therefore, the change in the food temperature of the food is extremely small, and the quality is hardly affected.

(Regarding defrosting operation) As described above, the refrigerator according to the present embodiment mainly includes
The cooled brine is circulated through the first cooler 17 to cool the inside of the refrigerator. This brine-cooled refrigerator can circulate a large amount of brine with a large specific heat as compared to a normal refrigerator that uses an evaporator as a cooling source, so that the difference between the inside temperature and the surface temperature of the cooler can be reduced. There is.

However, even if the refrigerator is a brine cooling type refrigerator, if the temperature inside the refrigerator is set to around 0 ° C or below 0 ° C, the first cooler 17
Since the surface temperature of is equal to or lower than 0 ° C., the moisture in the air is condensed and frozen on the surface of the cooler, and becomes frost, which gradually forms in layers. If this frost grows large, as described above, heat exchange between the first cooler 17 and the inside of the refrigerator is hindered, and the inside of the refrigerator cannot be cooled to the set temperature. It causes harmful effects such as increase of Therefore, when the amount of frost in the first cooler 17 exceeds a predetermined value,
The cooling by the first cooler 17 is stopped and the following defrosting operation is started.

A case of performing the defrosting operation will be described with reference to the timing chart of FIG. As shown in the circuit connection diagram of FIG. 10, the contact X ₁ of the first defrosting means is connected in series with the defrosting thermo Th ₁ of the first cooler 17 and the defrosting heater H _1, and 2 The connection X _{2 of the} defrosting means is the second cooler 2
The second defrosting thermostat Th ₂ and the defrosting heater H ₂ are connected in series. As a result of cooling the inside of the refrigerator by the first cooler 17, when a required amount of frost adheres to the first cooler 17, the defrosting operation is started. That is, operation contact Th ₃ -b is switched at the internal thermo-Th _3, together with the contacts a-c is closed first solenoid valve V ₁ is opened to stop the rotation of the pump motor PM, the first cooling The cooling by the vessel 17 is stopped. The contact Th ₃ at the internal thermo Th ₃ -
The contact point ab of b is closed, the second solenoid valve V ₂ is opened, and the second
The inside of the refrigerator is cooled by the cooler 22.

Simultaneously with the opening of the contacts a-c, the contact X _{1 of the} defrosting means shown in the wiring diagram of FIG. 10 is closed, and the heater H ₁ is energized to heat the first cooler 17 to remove the contact. Frost operation is started. Further-compartment is cooled by the second cooler 22, and is held at a constant temperature by on-off operation of the contact Th ₃ -a in-compartment thermo Th _3. Note defrosting period of the first cooler 17, regardless of whether the thermo contact Th ₃ -a is in the on or off any of the states, thermo contact Th ₃ -b contacts a-
b remains closed.

When the frost formed in the first cooler 17 is melted and removed by the heater H ₁ , the temperature of the first cooler 17 rises. When the defrosting thermo Th ₁ detects this temperature rise and opens its contact, energization to the heater H ₁ is cut off. A short time after the energization of the heater H ₁ is cut off, the defrosting means operates to open the contact X ₁ and finish the defrosting of the first cooler 17. By the way, first
The second cooler 22 that was performing the cooling operation during the defrosting of the cooler 17 has a large temperature difference between the surface temperature of the cooler and the inside temperature of the cooler as described above, and therefore frost immediately adheres to the surface. To grow. Therefore, at the same time as the defrosting of the first cooler 17 ends,
It switched contact Th ₃ -b in the internal thermo-Th _3, the second solenoid valve V ₂ is closed by opening the contacts a-b, and stops the operation of the second cooler 22. Also, by closing the contacts a-c, the first solenoid valve
V ₁ is opened, the pump motor PM is rotated, and the cooling operation in the first cooler 17 by the brine is started.

Further, the contact X ₂ in the defrosting means is closed to energize the heater H ₂ to start defrosting the second cooler 22. Second cooler 22
During the defrosting period, the thermo contact Th ₃ -a is actuated on and off to keep the the refrigerator at a constant temperature by the first cooler 17. At this time, regardless of the on-off operation of the thermo-contact Th ₃ -a,
The contacts a-c of other thermo-contact Th ₃ -b remains closed. Therefore, as shown in FIG. 9, during the defrosting period of the second cooler 22, even if the inside temperature rises above the abnormal set temperature T ₂ to point C due to, for example, opening the door 4, the thermo contact Th ₃ −
The contacts a-c of b continue to be closed, the inside of the refrigerator is cooled by the first cooler 17, and the defrosting by the second cooler 22 is surely performed. During the defrosting period of the second cooler 22, if the internal temperature exceeds the abnormal set temperature T ₂ ,
Cooling of the cooler 17 lowers the internal temperature.

When frost of the second cooler 22 is melted removed by energization of the heater H _2, defrosting contacts thermo Th ₂ is opened, energization to the heater H ₂ is cut off. Then after a while defrosting means is actuated, with opening the contact X _2, releases the forced retention of the thermo-contact Th ₃ -b. As a result, the internal thermo Th ₃
The contact Th ₃ -b is switched upon detecting the abnormal set temperature T _2, and closing the contacts a-b with opening contacts a-c, cooling cycle is carried out as described above.

Incidentally, as shown in FIG. 11, a third contact Th ₃ -c at the internal thermo-Th _3, and a warning means BZ such as a buzzer connected in series, the abnormality setting temperature T ₂ is-compartment thermo Th ₃ detected then, contact Th ₃ -b with switching to the contact a-b-side from the contact a-c side, alarm means B to close the contact Th ₃ -c
Z may be activated. In this case, an alarm can notify the user of a long-term opening of the door, forgetting to close the door, and storage of other high-temperature foods to the nearby users. It is suitable.

(Regarding Operation Control Method According to Second Invention) Next, operation of the refrigerator operation control method according to the second invention of the present application will be described. It should be noted that since there are many parts that are basically common to the operation control method described with respect to the above-described first invention, description of overlapping parts will be omitted.

When (power-on from to the cooling in the refrigerator) Refrigerator power on, cold storage internal temperature because it has been kept at elevated ambient temperatures around than the upper limit set temperature T _1, the internal first contact Th ₃ -a thermo Th ₃ Is closed, the compressor CM and the fan motor FM ₃ are activated, and the operation of the refrigeration system 6 is started. The second contact Th ₃ -b in the internal thermo-Th _3, since the inside temperature is higher than the abnormal set temperature T _2, the contact a-
b is closed, the second solenoid valve V ₂ is opened, and the second fan motor FM ₃ is rotated. Furthermore, the fourth of the storage thermo Th ₃
Since the contact Th ₃ -d is closed, the fan motor FM ₁
And the pump motor PM is rotated. As a result, the refrigerant from the refrigeration system is circulated to the second cooler 22, and the inside of the refrigerator is cooled.

The fan motor FM ₁ circulates air in the refrigerator as shown by the solid line to promote heat exchange with the first cooler 17. The pump motor PM supplies the brine 46 from the brine tank 8 to the first cooler 17, and part of the returned brine 46 flows down to the brine tank 8 from the drain hole 53 of the brine detection tank 51, and most of it is brine. It is stored in the detection tank 51 and the liquid level gradually rises. Due to this rise in the liquid level, the brine 46 overflows from the upper edge portion 51c of the side wall of the detection tank 51 and begins to flow down to the brine tank 8 below. The float 55a of the float switch 55 starts to float as the liquid level in the tank 51 rises, closes internal contacts, and electrically detects that brine is circulating in the first cooler 17. To do.

The temperature of the brine at the start of the cooling operation is as high as the ambient temperature. When this brine is circulated to the first cooler 17 by the pump motor PM, the temperature of the cooler 17 rises first, but is cooled by the air circulation in the refrigerator by the fan motor FM ₁ . That is, the inside of the refrigerator is cooled by the second cooler 22 to which the refrigerant from the refrigerating device 6 is circulated and supplied, and the temperature inside the refrigerator gradually decreases. When the temperature of the inside air whose temperature has dropped is heat-exchanged with the first cooler 17 by the fan motor FM ₁ to cool the cooler 17, thereby lowering the temperature of the brine circulating in the first cooler 17, the brine is cooled. The temperature of the brine 46 in the tank 8 also gradually decreases. In this way, the inside of the refrigerator and the brine 46 are cooled by the second cooler 22.

When the inside of the refrigerator cools down and the temperature inside the refrigerator drops to the lower limit set temperature T ₀ of the inside thermostat Th ₃ , the contact Th _{3 in} FIG.
-A is released, and the rotations of the compressor CM and the fan motor FM ₃ are stopped. At the same time, the other contact point T of the inside thermostat Th ₃
h ₃ -b also switched, contacts a-c and contacts a-b is opened is closed. By opening the contacts a-b, the second solenoid valve V ₂
Is closed, the rotation of the fan motor FM ₂ is stopped, and the cooling by the second cooler 22 is stopped. On the other hand, the other contact a
By closing -c, the first solenoid valve V ₁ is opened and the refrigeration system 6
The flow of the liquefied refrigerant from the
A circulation cycle is formed towards the third cooler 47 therein.

The brine 46 in the brine tank 8 is the second cooler 22.
The temperature is cooled by, and becomes substantially equal to the lower limit set temperature T ₀ of the in-compartment thermostat Th ₃ . After the compressor CM is stopped, the inside of the storage is continuously cooled by the heat storage of the brine 46 via the first cooler 17, but the internal temperature of the storage 1a changes from the heat entering from the outside through the heat insulating material 16 and gradually increases due to the heat radiation or the like from the fan motor FM _1, reaches the upper limit set temperatures T ₁ set in the internal thermo-Th _3. Then closed contact point Th ₃ -a in the internal thermo-Th _3, to resume the rotation of the compressor CM and the fan motor FM _3, begins to cool the brine by the third cooler 47. This cooled brine is pump motor P
It is supplied to the 1st cooler 17 by M, and heat-exchanges with the air in a refrigerator here, and cools the inside of a refrigerator. The brine whose temperature has risen due to heat exchange returns from the discharge pipe 43 to the brine tank 8 via the return pipe 68, exchanges heat with the third cooler 47, is cooled again, and then goes to the first cooler 17 for a series of circulation. Repeat the cycle.

In this way, when the cycle of cooling the inside of the refrigerator by the cooled brine 46 is repeated, the temperature inside the refrigerator and the first cooler 1
The temperature difference from 7 is extremely small, and therefore the first cooler 1
The amount of frost on 7 is reduced and the inside of the refrigerator is kept at high humidity. Then, when the internal temperature decreases to the lower limit set temperature T ₀ of the internal thermo Th ₃ , the contact Th ₃ -a is opened and the rotation of the compressor CM and the fan motor FM ₃ is stopped. When the operation of the refrigeration system 6 is stopped in this way, the brine is not cooled by the third cooler 47. However, the amount of brine 46 stored in the brine tank 8 is several times the amount present in the pipeline for circulation, and the brine tank 8 uses the heat insulating material 32 to prevent heat from entering from the outside. Since it is cut off, the cold storage effect is high. Therefore, the brine 46 stored in the brine tank 8 is circulated by the pump motor PM and still continues to cool the first cooler 17.

However, the internal temperature of the storage case 1a depends on various factors such as heat entering from the outside through the heat insulating material 16, heat entering when the door 4 is opened and closed for accommodating and taking out food, and other heat radiation from the food itself. It gradually rises depending on the cause. Further, the first cooler 17 is also warmed by the air inside the refrigerator which is circulated by the fan motor FM ₁ , so that the brine circulating in the cooler 17 is also gradually warmed and the temperature of the brine in the brine tank 8 is gradually increased. Start climbing. When the internal temperature reaches the upper limit set temperature T ₁ of the internal thermo Th ₃ , the thermo Th ₃
Contact Th ₃ of -a is closed to resume the operation of the compressor CM and the fan motor FM _3. Therefore, the refrigerant circulates in the third cooler 47, and the cooling of the brine in the tank 8 is restarted.

The brine cooled in the third cooler 47 is used in the first cooler 1
7, the inside of the refrigerator is cooled, and the inside temperature is the lower limit set temperature.
At T ₀ , the contact Th ₃ −a of the internal thermostat Th ₃ opens,
The operation of the refrigeration system 6 is stopped. After that, the inside of the refrigerator is maintained at a constant temperature by repeating this process.

As previously mentioned, from the start of the cooling run to the inside temperature reaches the lower set temperature T ₀ of the internal thermo-Th _3, the second cooler 22
The inside of the refrigerator is cooled by the first cooler 17 so as to maintain the inside temperature between the upper limit set temperature T ₁ and the lower limit set temperature T ₀ of the inside thermostat Th _3. It

By the way, in the second cooler 22, the refrigerant in the refrigerating system is evaporated, and the evaporation temperature of this refrigerant is much lower than the internal temperature. Therefore, the temperature difference between the surface temperature of the second cooler 22 and the inside temperature is extremely large, and when heat is exchanged by circulating the inside air by the fan motor FM ₂ , the inside temperature is rapidly lowered. And the second cooler 22
Since the surface temperature of is less than 0 ° C, frost forms on the surface of the cooler. In addition, it is preferable to set the evaporation temperature of the refrigerant in the second cooler 22 to about −10 ° C. to −15 ° C. and increase the refrigerant circulation amount to enhance the cooling capacity of the second cooler 22. .

In the timing chart shown in FIG. 8, when the first cooler 17 keeps the inside of the refrigerator cooled and maintained within the upper limit set temperature T ₁ and the lower limit set temperature T ₀ of the inside thermostat Th ₃ ,
If the door 4 is opened at the point A and a large amount of still hot food is stored in the refrigerator, or if the door 4 is opened for a long time, the temperature in the refrigerator rapidly rises to the point B. The temperature in the refrigerator is from point A to point B
In the process of rising to the point, the upper limit set temperature T ₁ of the inside thermostat Th ₃
When passing through, and one closed contact point Th ₃ -a in the internal thermo-Th _3, the compressor CM and the fan motor FM ₃ for cooling the brine in the tank 8 to resume the rotation by the third cooler 47 . Note other contact Th ₃ -b in the internal thermo-Th ₃ is
Since the contacts a to c are still closed, the brine cooled by the third cooler 47 is circulated to the first cooler 17 to start cooling the inside of the refrigerator. Furthermore, the internal temperature rises toward point B,
When passing the abnormal set temperature T _2, the other contact Th ₃ -b in the internal thermo-Th ₃ is in switching operation, to close the contact point a-b with opening contacts a-c. By closing the contacts a-b, the second solenoid valve V ₂ is opened and the refrigerant in the refrigeration system is circulated in the second cooler 22. The fan motor FM ₂ also rotates,
The inside of the refrigerator is cooled by the second cooler 22.

For other contact Th ₃ -d in the internal thermo-Th ₃ remains closed, the brine into the first cooler 17 is cooled 46
Continues to circulate to cool the inside of the refrigerator. That is, when the internal thermostat Th ₃ detects the abnormal set temperature T ₂ , the internal refrigerator is cooled by both the first cooler 17 that uses the heat storage of the brine and the second cooler 22 that uses the vaporization of the refrigerant. Therefore, the cooling effect is high, and the internal temperature can be lowered from the point B to the lower limit set temperature T _{0 in a} short time. When the inside of the refrigerator reaches the lower limit set temperature T ₀ , one contact T of the inside thermostat Th ₃
h ₃ -a is opened and the compressor CM, to stop the fan motor FM _3. Also the other contact Th ₃ -b and switching operation, the contact a
-B is opened to stop the cooling in the second cooler 22, and the contacts a-c are closed to continuously cool the inside of the refrigerator by the first cooler 17.

In this way, when the internal temperature reaches the abnormal set temperature T ₂ that affects the quality of the food items stored in the storage 1a by cooling,
Since the first cooler 17 and the second cooler 22 are activated to lower the internal temperature in a short time, the quality of food can be maintained.

(Regarding Defrosting Operation) The defrosting operation by the refrigerator operation control method according to the second invention of the present application is basically the same as the defrosting operation by the operation control method according to the first invention described above. . That is, as shown in the timing chart of FIG. 9, the first cooler 1
When a required amount of frost adheres to the first cooler 17 as a result of cooling the inside of the refrigerator by 7, the defrosting operation is started. Then, the thermo contacts Th ₃ -b are switched and actuated, the contacts ac are opened and the first solenoid valve V ₁ is closed, and at the same time the rotation of the pump motor PM is stopped and the first cooler 1
Stop cooling by 7. The closed contact point a-b of contact Th ₃ -b at the internal thermo-Th _3, to cool the inside of the refrigerator by the second cooler 22 by opening the second solenoid valve V _2.

Simultaneously with the opening of the contacts a-c, the contact X _{1 of the} defrosting means shown in the wiring diagram of FIG. 10 is closed, and the heater H ₁ is energized to heat the first cooler 17 to remove the contact. Frost operation is started. However, the operation control method according to the second aspect of the invention, the fourth contact Th ₃ -d where the aforementioned first cooler 17
It is opened during the return of defrosting, and the rotations of the pump motor PM and the fan motor FM ₁ are stopped. The subsequent defrosting operation is the same as the case of the defrosting operation by the operation control method according to the first invention described above.

EFFECTS OF THE INVENTION As described above, the operation control method for a refrigerator according to the first invention of the present application is basically the first method in which brine is circulated and supplied.
A cooler cools the inside of the refrigerator to maintain a constant temperature and high humidity, and when the temperature inside the refrigerator rises abnormally, the cooling in the first cooler is interrupted, and the inside of the refrigerator is cooled by the second cooler, It is possible to cool the inside of the refrigerator in a short time when the temperature inside the refrigerator rises abnormally due to the opening and closing of the door and the storage of a large amount of high-temperature food. Further, in the refrigerator operation control method according to the second invention of the present application, basically, when the inside of the refrigerator is cooled by the first cooler to which brine is circulated and supplied to maintain constant temperature and high humidity, and the temperature inside the refrigerator rises abnormally. The first cooler uses the large heat storage of brine to continue cooling, and the second cooler circulates the refrigerant from the refrigeration system to cool the inside of the refrigerator. When the temperature inside the refrigerator rises abnormally due to a large amount of storage, the inside of the refrigerator can be cooled in a short time.

Therefore, it is possible to effectively avoid inconveniences such as deterioration of the quality of the stored food material and promotion of thawing of the slightly frozen food material. Moreover, since it is not necessary to increase the amount of heat stored in the brine more than necessary, the brine tank, the pump motor, and the first cooler can be downsized, and a refrigerator with a small installation area and a large internal volume can be manufactured at low cost. There are excellent advantages to get. Further, a compressor having a small refrigerating capacity can be used, and power consumption can be reduced.

[Brief description of drawings]

The drawings show an embodiment of a refrigerator in which the operation control method according to the present invention is preferably implemented. FIG. 1 is a front view of a constant temperature and constant humidity refrigerator, and FIG. FIG. 3 is a vertical sectional view showing the internal schematic structure of the refrigerator, FIG. 4 is a vertical sectional view showing the schematic structure of a brine tank equipped with a brine detection device, and FIG.
FIG. 4 is a schematic perspective view showing a state in which the lid of the brine tank shown in FIG. 4 is removed, and FIG. 6 is a pipeline connection of a brine circulation circuit incorporated in the refrigerator shown in FIG. 3 and a refrigerant circulation circuit from a refrigeration system. FIG. 7 is a schematic explanatory diagram showing a state, and FIG.
FIG. 8 is a circuit diagram showing an example of an electric control circuit used for carrying out the method according to the invention, FIG. 8 is a timing chart showing the behavior of each circuit element from power-on to cooling by the first cooler, and FIG. Is a timing chart showing the behavior of each circuit element during the cycle of the cooling operation and the defrosting operation,
0 and 11 are circuit connection diagrams, and FIG. 12 is a circuit diagram showing an example of an electric control circuit used for carrying out the method according to the second invention of the present application. 1 ... box body, 2 ... cooling unit portion 6 ... refrigeration system, 8 ... the brine tank 17 ... first cooler, 22 ... second cooler 47 ... third cooler 51 ... brine detection tank FM _1, FM ₂ ... Fan Motor Th ₁ , Th ₂ ... Defrosting thermo Th ₃ ... Inside thermos, H ₁ , H ₂ ... Heater CM ... Compressor, V ₁ , V ₂ ... Solenoid valve

Claims (2)

[Claims] 1. A refrigeration system comprising a storage (1a) defined inside a box (1), a refrigerant compressor (CM), a condenser (7) and the like.
(6), a brine tank (8) for storing the brine (46), and the brine tank (8) disposed in the storage (1a)
The first cooler (17) to which the brine (46) is supplied, and the refrigerant from the refrigeration system (6), which is disposed in the storage (1a), is always in the closed state. 2 The second cooler (22) supplied by opening the solenoid valve (V ₂ ), and the refrigeration system (6) provided in the brine tank (8)
In a refrigerator constituted by a third cooler (47) to which the refrigerant from is always supplied via the first electromagnetic valve (V ₁ ) which is in an open state, the first cooler (17) is always provided. By controlling the cooling operation and the cooling operation stop of the inside of the refrigerator, the inside temperature is maintained between the upper limit set temperature (T ₁ ) and the lower limit set temperature (T ₀ ), and the inside upper limit set temperature (T ₁ ) When the temperature in the refrigerator rises above the predetermined temperature (t), the cooling operation of the first cooler (17) is stopped and the second solenoid valve (V ₂ ) is opened to release the refrigerant. By supplying to the second cooler (22), the second cooler (2
A refrigerator operation control method characterized by starting the cooling operation of 2). 2. A refrigeration system comprising a storage (1a) defined inside a box (1), a refrigerant compressor (CM), a condenser (7) and the like.
(6), a brine tank (8) for storing the brine (46), and the brine tank (8) disposed in the storage (1a)
The first cooler (17) to which the brine (46) is supplied, and the refrigerant from the refrigeration system (6), which is disposed in the storage (1a), is always in the closed state. 2 The second cooler (22) supplied by opening the solenoid valve (V ₂ ), and the refrigeration system (6) provided in the brine tank (8)
In a refrigerator constituted by a third cooler (47) to which the refrigerant from is always supplied via the first electromagnetic valve (V ₁ ) which is in an open state, the first cooler (17) is always provided. By controlling the cooling operation and the cooling operation stop of the inside of the refrigerator, the inside temperature is maintained between the upper limit set temperature (T ₁ ) and the lower limit set temperature (T ₀ ), and the inside upper limit set temperature (T ₁ ) is set. When the temperature in the refrigerator rises above the predetermined temperature (t), the cooling operation of the first cooler (17) is continued and the second solenoid valve (V ₂ ) is opened to cause the refrigerant to flow. Is supplied to the second cooler (22), and the inside of the refrigerator is cooled by both coolers (17, 22).