JP2006029643A - Freezer for freezing refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a freezer capable of efficiently absorbing water in the case of a carbon dioxide refrigerant and reducing factors for causing the global warming and destruction of an ozone layer by considering a problem that a dryer is not used and a water supplement agent is added in a refrigerant circuit using a carbon dioxide as a refrigerant, although a water absorption effect is hardly observed and a possibility of the breakage of synthetic zeolite for drying is large when dehydrating by a dryer inserted into a general refrigerant circuit using the carbon dioxide as the refrigerant in series. <P>SOLUTION: In this freezer, the refrigerant circuit is constituted to allow the carbon dioxide refrigerant compressed at two steps by a compressor to pass through a radiator, a dryer, a capillary tube, an electric expansion valve, and an evaporator for cooling the inside of a cooling vessel sequentially and return to a compression part at one step of the compressor. A desiccant in the dryer is substantially a molecular sieve which removes moisture in the refrigerant circuit but does not absorb the carbon dioxide. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a refrigeration apparatus for a refrigerator using a carbon dioxide refrigerant.

In a refrigeration system that circulates carbon dioxide as a refrigerant in a refrigeration circuit including a compressor, a radiator, an expansion mechanism, and an evaporator, a specific refrigeration oil used in the compressor is used to capture moisture in the refrigeration circuit There is one using synthetic zeolite as a desiccant in the drying apparatus (for example, see Patent Document 1).

In a refrigerant circuit for commercial air conditioners that switches the refrigerant flow path between a cooling operation and a heating operation by switching a four-way valve, molecular sieves are stored between the outdoor heat exchanger and the capillary tube for moisture removal. Some dryers are connected and vibrations of the dryer are suppressed to prevent the molecular sieves from being pulverized (see, for example, Patent Document 2).
JP 2001-255043 A JP 2001-141341 A

In a general refrigerant circuit using carbon dioxide as a refrigerant, it is known that dehydration with a dryer inserted in series in the refrigerant circuit has almost no water absorption effect and the possibility of damage to the synthetic zeolite for drying is great. Yes. That is, it is known that in a refrigerant circuit using carbon dioxide as a refrigerant, a moisture supplement is added without using a dryer.

In the refrigeration apparatus according to the first aspect of the present invention, the carbon dioxide refrigerant compressed in two stages by the compressor passes through the radiator, the dryer, the capillary tube, the electric expansion valve, and the evaporator for cooling the inside of the refrigerator in order. A refrigerant circuit that returns to the first stage compression unit of the machine is configured, and a molecular sieve that substantially removes moisture in the refrigerant circuit but does not adsorb carbon dioxide is housed as a desiccant for the dryer.

In the refrigeration apparatus according to the second aspect of the invention, the carbon dioxide refrigerant compressed in two stages by the compressor includes a radiator, a dryer, a first capillary tube, a first electric expansion valve, a gas-liquid separator, a second capillary tube, a second A first refrigerant path that sequentially passes through an electric expansion valve and an evaporator for cooling the inside of the refrigerator and returns to the first stage compression unit of the compressor, and the refrigerant gas separated by the gas-liquid separator is compressed. The second refrigerant path to be introduced into the second stage compression section of the machine is configured, and as a desiccant for the dryer, water is substantially removed from the refrigerant circuit consisting of the first and second refrigerant paths, but carbon dioxide is adsorbed. It is characterized by storing the molecular sieve that does not.

In the refrigeration apparatus of the third invention, the carbon dioxide refrigerant compressed in two stages by the compressor passes through the radiator, the dryer, the first capillary tube, the first electric expansion valve, and the gas-liquid separator, and then the capillary tube for the refrigerator compartment Through a parallel circuit of a passage flowing from the capillary tube for the freezer compartment to the evaporator for the refrigerating chamber and a passage flowing from the capillary tube for the freezer compartment through the third electric expansion valve to the evaporator for the freezer compartment. A refrigerant circuit that returns to the first stage compression unit of the compressor is configured, and a molecular sieve that substantially removes moisture in the refrigerant circuit but does not adsorb carbon dioxide is housed as a desiccant for the dryer.

According to the first invention, it is possible to provide a refrigeration apparatus that causes less global warming and ozone layer destruction by circulating a carbon dioxide refrigerant. In that case, moisture is substantially removed from the refrigerant circuit by a dryer. Does not adsorb carbon dioxide, the adverse effect of moisture in the refrigerant circuit can be removed, and a stable compressor capacity can be obtained. When carbon dioxide is adsorbed by a dryer, the amount of circulating refrigerant is reduced. However, in the present invention, there is no such effect, so that the intended refrigeration capacity can be exhibited.

In the second invention, in addition to the effects of the first invention, the gas refrigerant separated by the gas-liquid separator is compressed by the second-stage compression part of the compressor and flows into the radiator, so that the cooling capacity of the refrigeration apparatus Improved,
It becomes the refrigerator-freezer from which effective cooling is obtained.

In addition to the effects of the first invention, the third invention is effective as a refrigerator-freezer in which the freezer compartment and the refrigerator compartment are cooled by separate evaporators.

The present invention is a refrigeration apparatus for a refrigerator, wherein the carbon dioxide refrigerant compressed in two stages is a radiator,
A refrigerant circuit that sequentially passes through a dryer, a capillary tube, and an evaporator for cooling the inside of the refrigerator and returns to the one-stage compression unit of the compressor is configured, and moisture in the refrigerant circuit is substantially used as a desiccant for the dryer. It is characterized by containing a molecular sieve which is removed but does not adsorb carbon dioxide. Examples of the invention are described below.

Next, an embodiment of the present invention will be described. 1 is a front view of a refrigerator-freezer according to the present invention, FIG. 2 is an explanatory view of the refrigerator-freezer body according to the present invention as viewed from the front, FIG. 3 is a longitudinal side view of the refrigerator-freezer according to the present invention, and FIG. FIG. 5 is an explanatory diagram of refrigerant circuit piping of the refrigeration apparatus according to the present invention.

Next, an embodiment of the present invention will be described. Reference numeral 1 denotes a refrigerator-freezer which is one of the cooling storages of the present invention, which has a structure in which a main body 2 having a full opening is partitioned to form a plurality of storage chambers, and the front surfaces of these storage chambers can be opened and closed by doors. The refrigerator-freezer body 2 includes an outer box (outer wall plate) 2A and an inner box (
It is a heat insulating structure filled with foam heat insulating material 2C between the inner wall plate 2B. A refrigerator compartment 3, a vegetable compartment 4, and a freezer compartment 5 (consisting of an upper freezer compartment 6 A, a lower freezer compartment 6 B, and an ice making chamber 7) are formed in the freezer / refrigerator body 2 from above, and are attached to the upper refrigerator compartment 6 A The ice making chamber 7 is partitioned and a specific low temperature chamber 9 partitioned by a refrigerator chamber 3 and a partition plate (partition wall) 8 above is provided at the bottom of the refrigerator 3.

The front opening of the refrigerating room 3 is closed by a revolving refrigerating room door 10 that is opened and closed by being pivoted laterally by a hinge device at one side of the refrigerator-freezer body 2. In the refrigerating chamber 3, a plurality of shelves 41 placed on a shelf receiver 42 formed on the side wall of the refrigerating chamber 3 are provided. The front opening of the vegetable compartment 4 is a drawer-type door 11 that is drawn forward together with the vegetable container 15 having an upper opening that is supported so that it can be pulled out in the front-rear direction by left and right rails and rollers provided in the vegetable compartment 4. It is blocked. The upper freezer compartment 6A and the lower freezer compartment 6B, like the vegetable compartment 4, are containers 16 and 1 that are supported so that they can be pulled out in the front-rear direction with respect to the left and right rails provided in the freezer compartment.
7 is closed by pull-out doors 12 and 13 that are drawn forward together.

An automatic ice making machine 18 and an ice storage box 19 are provided in the ice making room 7, and a water supply container 20 for storing ice making water to be supplied to the automatic ice making machine 18 is stored in a small room in the refrigerating room 3 attached to the specific low temperature room 9. Is stored. The ice making water is sucked up by the pump 60 from the water supply container 20 and supplied to the ice making tray 22 of the automatic ice making machine 18 through the water supply pipe 61.

The refrigerator door 10 has a heat insulating structure in which a foamable heat insulating material 10C is filled between the outer plate 10A and the inner plate 10B, and is integrally formed with the inner plate 10B on the left and right sides of the inner plate 10B or separately. Side walls 10 </ b> D and 10 </ b> E extending in the vertical direction are formed by the members. Article storage shelves 38, 38A, 38B, 38C, 38D called pockets are formed in a plurality of stages between the side walls 10D, 10E, and storage for storing the seasoning 45 in a sachet in one or more of the shelves. A portion 46 is formed.

Reference numeral 24 denotes an electric compressor that compresses the refrigerant of the refrigeration apparatus, and reference numeral 25 denotes a refrigerant radiator of the refrigeration apparatus.
Reference numeral 26 denotes an evaporating dish for evaporating defrosted water, which will be described later, by heat from the radiator 25C. The compressor 24, the radiator 25 </ b> C, and the evaporating dish 26 are installed in a machine room 28 provided at the lower part of the refrigerator body 2. 2
Reference numerals 9 and 30 denote refrigerant evaporators (coolers) of the refrigeration apparatus. 31 is a freezer cooler
This is a first blower that circulates the cold air cooled by the evaporator (cooler) 29 to the upper freezing room 6A, the lower freezing room 6B, and the ice making room 7. Reference numeral 32 denotes a second blower that circulates the cold air cooled by the second evaporator (cooler) 30, which is a refrigerator for the refrigerator compartment, to the refrigerator compartment 3, the vegetable compartment 4, and the specific low temperature compartment 9. 33 is the first
Defrosting glass tube heater 34 of evaporator (cooler) 29 is a defrosting glass tube heater of second evaporator (cooler) 30. The defrost water from the first evaporator (cooler) 29 and the second evaporator (cooler) 30 is led to the evaporating dish 26 through the drain pipe and is evaporated there.

The refrigeration apparatus is shown in FIGS. Carbon dioxide refrigerant is used as the refrigerant. The compressor 24 compresses the refrigerant in two stages by the first-stage compression unit 24A and the second-stage compression unit 24B.
Two known rotors each having a rotor that is rotated by an electric motor (motor) in a sealed container
Although it is a rotary compressor of a cylinder (referred to as a rotary compressor) and constitutes a first-stage compression section 24A and a second-stage compression section 24B, other forms in which refrigerant is compressed in two stages may be used.

25A to 25E constitute the refrigerant radiator 25, which is an air-cooled type, and the radiator 25A is a first-stage radiator constituted by a plate type.
Heat exchanged by wind from. The radiator 25B is a main radiator composed of a fin tube type in which a large number of fins are attached around a refrigerant pipe (tube).
It is a unit configuration surrounded by a frame together with the blower 81 so that heat is exchanged by wind from the blower 81 inside. The radiator 25C has a configuration in which refrigerant pipes are arranged in a meandering manner on the back surface of a metal plate on which the evaporating dish 26 is placed. The radiator 25D is an outer box of the refrigerator refrigerator body 2 (
It is a refrigerant pipe attached to the surface of the outer casing (outer wall plate) 2A on the foam heat insulating material 2C side so that the outer wall plate) 2A serves as a heat sink.

The radiator 25E is an anti-deposition radiator that prevents the front opening of the refrigerator-freezer main body 2 from being deposited, and is a foam heat insulating material for the outer box (outer wall plate) 2A so as to heat the outer box (outer wall plate) 2A. A refrigerant pipe 25E1 for heating the front surface of the partition wall 52 between the refrigerator compartment 3 and the vegetable compartment 4 and a partition between the vegetable compartment 4 and the upper freezer compartment 6A, which are refrigerant pipes attached to the surface on the 2C side. A refrigerant pipe 25E2 for heating the front surface of the wall and a refrigerant pipe 25E3 for heating the front surface of the partition wall between the upper freezing chamber 6A and the lower freezing chamber 6B are formed by bending a series of pipes.

70 is a dryer which is a dryer, and 71 is a gas-liquid separator. Reference numerals 72, 73, and 74 denote electric expansion valves, and reference numerals 75, 76, and 77 denote capillary tubes. A pair of the electric expansion valve and the capillary tube constitute each pressure reducing device. Reference numerals 78, 79 and 80 denote check valves. In FIG. 4, the thick arrow indicates the flow direction of the refrigerant, and the arrow in FIG. 5 also indicates the flow direction of the refrigerant.

In such a refrigeration circuit shown in FIG. 4, when the carbon dioxide refrigerant changes its state in the supercritical region on the high pressure side of the refrigeration circuit, it may not be liquefied, and the decompression rate by the decompression device needs to be increased. A single electric expansion valve cannot provide sufficient pressure reduction. In addition, when the radiator 25 is air-cooled as described above, the refrigerant pressure increases in a situation where the ambient temperature is high,
If an attempt is made to reduce the pressure to a predetermined pressure using only a capillary tube as a pressure reducing device, the loss becomes too large. For this reason, even when carbon dioxide refrigerant changes its state in the supercritical region on the high pressure side of the refrigeration circuit, a capillary tube and an electric expansion valve are arranged downstream of the capillary tube as a pressure reducing device so that an appropriate pressure reducing effect can be obtained. It is configured. As a result, when the state of the refrigerant changes in the supercritical region, the refrigerant expands in the supercritical region in the capillary tube, and the refrigerant expands in the gas-liquid two-phase region in the electric expansion valve. I have to.

In such a refrigeration circuit, the high-temperature and high-pressure refrigerant gas compressed by the first-stage compression unit 24A of the compressor 24 is radiated by the radiator 25A and compressed by the second-stage compression unit 24B of the compressor 24. . The high-temperature and high-pressure refrigerant gas compressed by the second-stage compression unit 24B is cooled by the air from the blower 81 in the radiator 25B, and the refrigerant temperature is lowered while the state changes in the supercritical region. The temperature drops to a temperature slightly higher than the ambient temperature of the refrigerator-freezer 1 through the containers 25C and 25D. And the front-surface opening part of the refrigerator-freezer main body 2 is heated with the refrigerant | coolant which flowed into the heat radiator 25E, and it acts so that the dew condensation to the part may be prevented.

The refrigerant that has exited the radiator 25E passes through the dryer 70, is reduced in pressure through the capillary tube 75, which is a decompression device, and the electric expansion valve 72, the temperature is lowered, and flows into the gas-liquid separator 71. In this case, when the state of the refrigerant changes in the supercritical region, the refrigerant expansion process in the supercritical region is performed in the capillary tube 75, and the refrigerant expands in the gas-liquid two-phase region in the electric expansion valve 72. Is called. The low-temperature refrigerant that has exited the electric expansion valve 72 flows into the gas-liquid separator 71, and the gas-liquid separator 71.
A refrigerant circuit is formed so that the gas refrigerant separated in step S1 flows through the check valve 78 to the suction side of the second-stage compression unit 24B and is compressed.

The liquid refrigerant separated by the gas-liquid separator 71 is divided into two parts, one of which is decompressed through the capillary tube 76 which is a decompression device and the electric expansion valve 73 to lower the temperature, and the first evaporator (cooler) 29.
Flow into. Further, the pressure is reduced through the capillary tube 77 which is a decompression device and the electric expansion valve 74, and the temperature is lowered, and flows into the second evaporator (cooler) 30. The liquid refrigerant that has flowed into the first evaporator (cooler) 29 and the second evaporator (cooler) 30 evaporates there and cools the surrounding air. The gas refrigerant evaporated in the first evaporator (cooler) 29 passes through the check valve 79 and flows into the suction side of the first stage compression unit 24A of the compressor 24 to be compressed. Further, the gas refrigerant evaporated by the second evaporator (cooler) 30 flows into the suction side of the first-stage compression unit 24A of the compressor 24 and is compressed. With such a refrigeration cycle, the first evaporator (cooler) 29 and the second evaporator (cooler) 30 are cooled, thereby cooling each chamber in the refrigerator-freezer main body 2 as described later.

In the above refrigeration apparatus, the electric expansion valve 72 has its valve opening adjusted by a stepping motor that performs forward and reverse operations according to a control signal, and a control circuit according to the outlet temperature of the radiator 25. Based on data set in an apparatus (not shown), the stepping motor is rotated forward or backward to adjust the valve opening so that proper refrigerant expansion is performed.

Further, the opening degree of the electric expansion valve 73 is adjusted by a stepping motor that performs forward and reverse operations according to a control signal, and the control is performed according to the outlet temperature of the evaporator (cooler) 29. Based on data set in a circuit device (not shown), the stepping motor rotates forward or backward to adjust the valve opening so that proper refrigerant expansion is performed.

Reference numeral 35 denotes a cold air duct through which the cold air cooled by the second evaporator (cooler) 30 is guided from the second blower 32, and is widely disposed on the upper wall 45 of the refrigerator compartment 3, and the front end thereof is the front opening of the refrigerator compartment 3. It communicates with the cold air outlet 36 formed on the upper surface of the part. The cold air blown out from the cold air outlet 36 forms a cold air curtain 37 that flows from the top to the bottom as indicated by the arrow in the front opening of the refrigerator compartment 3. The cold air cooled by the first evaporator (cooler) 29 and the cold air cooled by the second evaporator (cooler) 30 are circulated as indicated by arrows by the first blower 31 and the second blower 32, respectively, and each chamber is circulated. Cool to a predetermined temperature.

Regarding the formation of a cold air circulation path in which the cold air cooled by the second evaporator (cooler) 30 is circulated to the refrigerator compartment 3 and the vegetable compartment 4 by the second blower 32, cold air passages are provided on the left and right sides of the rear portion of the refrigerator compartment 3. 43A and 43B are formed, and a cold air return passage 44 communicating with the lower side of the second evaporator (cooler) 30 is formed between the left and right cold air passages 43A and 43B.

The cold air cooled by the second evaporator (cooler) 30 is circulated between the refrigerator compartment 3 and the vegetable compartment 4 by the second blower 32. In the path, a part of the cold air passing through the second blower 32 is blown out from the cold air outlet 36 through the cold air duct 35. The other part of the cool air that has passed through the second blower 32 passes through the left and right cool air passages 43A and 43B on the back side of the back plate 40 of the refrigerating room 3, and the refrigerating room 3
From the cold air outlet 39 formed in the back plate 40 of the rear plate 40 to the refrigerator compartment 3,
A part of the cold air blows out from the cold air outlet 39A to the specific low temperature chamber 9 while flowing further down 43B.

The cold air that has flowed further downward in the left and right cold air passages 43A and 43B passes from the cold air outlet 50 to the refrigerator compartment 3.
And a cold air passage 51 formed between the vegetable compartment 4 and the vegetable compartment 4. The cold air passage 51 is formed between the partition wall 52 between the refrigerator compartment 3 and the vegetable compartment 4 and the ceiling plate 53 of the vegetable compartment 4. Partition wall 52
Constitutes the bottom wall of the refrigerator compartment 3, and the ceiling plate 53 of the vegetable compartment 4 is arranged at a position that substantially closes the top opening of the vegetable container 15, so that the vegetable can be removed forward from the vegetable compartment 4. The left and right walls of the chamber 4 and / or the partition walls 52 are supported. A part of the cool air that has cooled the refrigerator compartment 3 and the specific low temperature chamber 9 flows into the cool air passage 51 from the suction port 56 formed in the partition wall 52. Since the vegetable container 15 can be pulled out forward, when the vegetable container 15 is stored in the vegetable compartment 4, the top opening of the vegetable container 15 is covered with the ceiling plate 53 by the ceiling plate 53 of the vegetable compartment 4. is there.

The cold air supplied to the cold air passage 51 flows forward through the cold air passage 51, flows down from the front end outlet 54 to the vegetable compartment 4, and surrounds the vegetable container 15 from the space formed between the vegetable container 15 and the door 11. The air is sucked from the cold air suction port 55 formed on the back surface of the vegetable compartment 4 through the space formed in the above.

Since a cold air return passage 44 is formed between the back plate 40 and the main body 2 between the left and right cold air passages 43A and 43B on the back side of the refrigerator compartment 3, the cold air in the vegetable compartment 4 is sucked from the cold air suction port 55. Then, it flows into the cool air return passage 44, flows into the lower side of the second evaporator (cooler) 30, and circulates again cooled by the second evaporator (cooler) 30.

In such a configuration, the temperature of each room is about 3 to 4 ° C. in the refrigerator room 3 and about 3 to 6 in the vegetable room 4.
The freezing room 5, that is, the upper freezing room 6A and the lower freezing room 6B, and further the ice making room 7 are maintained at about -18 ° C.
~ -20 ° C. Moreover, it is 5-8 degreeC on the storage shelf 38 provided inside the refrigerator compartment door 10. FIG.
The specific low-temperature chamber 9 is a chilled chamber of about 1 ° C. higher than 0 ° C., an ice greenhouse of about 0 to 1 ° C. lower than 0 ° C. and higher than the freezing temperature of food, It may be a partial freezing chamber at about −4 ° C. so that a thin ice layer is formed on the surface. As described above, the specific low temperature chamber 9 is used for refrigerated storage of food in a specific temperature range, and requires stricter temperature control than other rooms.

Thus, in the refrigeration apparatus of the present invention, the carbon dioxide refrigerant compressed in two stages by the compressor 24 is
After passing through the radiator 25, the dryer 70, the first capillary tube 75, the first electric expansion valve 72, and the gas-liquid separator 71, the refrigerating room capillary tube 77 and the electric expansion valve 74 are transferred to the refrigerating room evaporator 30. A refrigerant circuit is configured to return to the first stage compression unit 24A of the compressor 24 through a parallel circuit of the flowing passage and the passage flowing from the freezer capillary tube 76 and the electric expansion valve 73 to the freezer evaporator 29. .

In the compressor 24 that compresses the carbon dioxide refrigerant at a high pressure, the carbon dioxide may be in a supercritical state. Even when carbon dioxide is in a supercritical state, materials and lubricating oil are used so that substantially no physical or chemical adverse effects occur in each part of the refrigeration apparatus.

In this way, carbon dioxide refrigerant is used in the refrigerant circuit, and in order to remove moisture in the refrigerant circuit by adsorption, the dryer 70 is used as a desiccant between the filters provided on the inlet side and the outlet side, respectively. Contains molecular sieves. This molecular sieve has the characteristic of substantially removing moisture in the refrigerant circuit but not adsorbing carbon dioxide, thereby preventing the cooling capacity from being lowered due to insufficient circulating carbon dioxide. .

Moreover, in this invention, as another Example, each chamber in the refrigerator-freezer main body 2 can also be comprised so that it may cool with a single evaporator (cooler). In this case, in each said figure, it can comprise so that cold air circulated to the refrigerator compartment 3, the vegetable compartment 4, and the freezer compartment 5 with the 1st air blower 31 by the cold air cooled with the 1st evaporator (cooler) 29. FIG. it can. In this case, as the refrigerant circuit of the refrigeration apparatus, the carbon dioxide refrigerant compressed in two stages by the compressor 24 includes the radiator 25, the dryer 70, the first capillary tube 75, the first electric expansion valve 72, and the gas-liquid separator. 71, second
Capillary tube 76, second electric expansion valve 73, evaporator 31 for cooling the inside of the refrigerator
The first refrigerant circuit that sequentially returns to the first stage compression unit 24A of the compressor 24, and the gas-liquid separator 7
2 constitutes a second refrigerant circuit for introducing the refrigerant gas separated in 1 into the second-stage compression unit 24B of the compressor 24.

Also in such a refrigeration apparatus, the desiccant of the dryer 70 is configured to contain a molecular sieve that substantially removes moisture in the refrigerant circuit but does not adsorb carbon dioxide.

Therefore, the common basic configuration of the present invention including the first and second embodiments is that the carbon dioxide refrigerant compressed in two stages by the compressor 24 is condensed by the radiator 25 and moisture is removed by the dryer 70. Then, the refrigerant enters the evaporator for cooling the inside of the refrigerator through the capillary tube as the decompression device and the electric expansion valve in sequence, and the refrigerant exiting the evaporator returns to the first stage compression unit 24A of the compressor 24. And a molecular sieve that substantially removes water in the refrigerant circuit but does not adsorb carbon dioxide as a desiccant for the dryer.

Since the present invention is effective when applied to a refrigerator-freezer provided with a refrigeration circuit using a carbon dioxide refrigerant, the present invention can be applied to refrigerators of various forms.

It is a front view of the present invention refrigerator-freezer. (Example 1) It is explanatory drawing which looked at the refrigerator-freezer main body of this invention from the front. (Example 1) It is a vertical side view of this invention refrigerator-freezer. (Example 1) It is a block diagram which shows the freezing apparatus which concerns on this invention with a block. (Example 1) It is explanatory drawing of refrigerant circuit piping of the freezing apparatus which concerns on this invention. (Example 1)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Refrigeration refrigerator 2 ... Refrigeration refrigerator main body 3 ... Refrigeration room 4 ... Vegetable room 5 ... Freezing room 6 ... Ice making room 7 ... Automatic ice making machine 9 ... Water supply container 24..Electric compressor 24A..First stage compression section 24B..Second stage compression section 25..Radiator 25A..First stage radiator 25B..Main radiator 25C..Evaporation dish radiator 25D .. Wall pipe 25E ... Anti-deposition radiator 29 ... First evaporator (cooler)
30 ・ ・ Second evaporator (cooler)
31 .. First blower 32 .. Second blower 70 .. Dryer 71 .. Gas-liquid separator 72 .. First electric expansion valve 73 .. Second electric expansion valve 74 .. Third electric expansion valve 75 .. First capillary tube 76 .. Second capillary tube 77 .. Third capillary tube

Claims (3)

The carbon dioxide refrigerant compressed in two stages by the compressor returns to the one-stage compression section of the compressor through the radiator, the dryer, the capillary tube, the electric expansion valve, and the evaporator for cooling the inside of the refrigerator in order. A refrigerating apparatus for a refrigerator-freezer comprising a refrigerant circuit and containing a molecular sieve that substantially removes water in the refrigerant circuit but does not adsorb carbon dioxide as a desiccant for the dryer. The carbon dioxide refrigerant compressed in two stages by the compressor is a radiator, dryer, first capillary tube, first electric expansion valve, gas-liquid separator, second capillary tube, second electric expansion valve, inside the refrigerator. A first refrigerant path that sequentially returns to the first stage compression unit of the compressor through the evaporator for cooling the refrigerant, and the refrigerant gas separated by the gas-liquid separator to the second stage compression unit of the compressor The second refrigerant path to be introduced is configured, and a molecular sieve that substantially removes moisture but does not adsorb carbon dioxide in the refrigerant circuit consisting of the first and second refrigerant paths as a desiccant for the dryer is stored. A refrigerating apparatus for a refrigerator-freezer characterized. The carbon dioxide refrigerant compressed in two stages by the compressor passes through the radiator, the dryer, the first capillary tube, the first electric expansion valve, and the gas-liquid separator, and passes through the second electric expansion valve from the cold storage capillary tube. Through the passage flowing through the refrigerator compartment evaporator and the freezer compartment capillary tube
A refrigerant circuit that returns to the first stage compression unit of the compressor through a parallel circuit with a passage that flows through the electric expansion valve to the evaporator for the freezer compartment is configured, and substantially in the refrigerant circuit as a desiccant for the dryer A freezer for a refrigerator that contains a molecular sieve that removes water but does not adsorb carbon dioxide.

Images