JP2005214489A - Refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerator comprising a two-stage compressor for preventing the shortage in cooling during a F cooling mode. <P>SOLUTION: In this refrigerator, a flow rate adjustment device 39 switches a first cooling mode (simultaneous cooling mode) for passing a refrigerant through at least a first evaporator 32 and a second evaporator, and a second cooling mode (F cooling mode) for passing the refrigerant through only the first evaporator 32, and heat radiation of a condenser 37 by a radiation fan 38 is reduced in the second cooling mode (F cooling mode) S1, in comparison with that in the first cooling mode (simultaneous cooling mode) S4, S5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a refrigerator provided with a two-stage compressor, and more particularly to a method for controlling a radiating fan that radiates heat from a condenser.

Hermetic reciprocating motion that performs two-stage compression in a refrigeration cycle that includes a condenser, a refrigeration evaporator and a refrigeration evaporator having different evaporation temperatures, and a flow rate adjusting device that varies the amount of refrigerant flowing to both evaporators A refrigerator using a compressor is considered (for example, see Patent Document 1).

In general refrigerators, a heat radiating fan for radiating heat from the condenser is provided, and the rotation is controlled based on the rotational speed of the compressor, the outside air temperature, and the like.
JP 2002-277082 A

However, in a refrigerator using a compressor that performs such two-stage compression, rotation control of the heat dissipation fan has not been studied.

In such a refrigerator, a simultaneous cooling mode in which the refrigerant is supplied to both the refrigeration evaporator and the freezing evaporator, an F cooling mode in which the refrigerant is supplied only to the freezing evaporator, and the like can be considered. When the same rotation control of the heat dissipating fan was performed regardless of the cooling mode using the control method, it was found that insufficient cooling occurred during the F cooling mode.

In view of the above problems, an object of the present invention is to provide a refrigerator including a two-stage compressor that prevents the occurrence of insufficient cooling during the F cooling mode.

In order to solve the above-described problems, a refrigerator according to the present invention includes a refrigerator main body in which a heat insulating material is filled between an outer box and an inner box, and a first evaporator and a first evaporator disposed in the refrigerator main body and having different evaporation temperatures. 2
An evaporator, a flow rate adjusting device that varies a flow rate of refrigerant flowing through the first evaporator or the second evaporator, a first compression unit, and a second compression unit, wherein the first compression unit is a first evaporator; The compressor compresses the evaporated refrigerant gas, the second compressor compresses the refrigerant gas evaporated by the second evaporator and the refrigerant gas discharged from the first compressor, and discharges the refrigerant gas out of the case. A condenser for condensing the discharged refrigerant, and a heat dissipating fan for radiating heat from the condenser;
A first cooling mode in which the refrigerant flows through the evaporator and the second evaporator, and a second mode in which the refrigerant flows through only the first evaporator.
Switching to the cooling mode is performed, and in the second cooling mode, heat dissipation of the condenser by the heat radiating fan is suppressed more than in the first cooling mode.

According to the said invention, the refrigerator provided with the two-stage compressor which prevents that the cooling shortage generate | occur | produces during F cooling mode can be provided.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 2 which is a longitudinal sectional view of the refrigerator according to the present invention, the refrigerator main body 1 has a rectangular box-shaped heat insulation box 2 filled with a heat insulating material 2c between the outer box 2a and the inner box 2b. In order from the top, it has a refrigerator compartment 3, a vegetable compartment 4, a switching chamber 5, and a freezer compartment 6. Although not shown in particular, an ice making chamber is provided with the switching chamber 5. The front opening of the main body 1 is provided with doors 7 to 10 that sequentially close the storage chambers 3 to 6 in an openable manner.

The refrigerator compartment 3 and the vegetable compartment 4 are maintained in a temperature range of approximately 1 to 5 degrees, and each is divided into a partition plate 11.
It is divided by. On the back of the vegetable compartment 4, a refrigerator 27 (hereinafter referred to as "R EVA"), which is a second evaporator, is provided, and in the upper part thereof, a refrigerator compartment fan 28 (hereinafter referred to as "R fan"). Provided). When the R fan 28 is operated, the cold air generated by the R evaporator 27 is supplied to the refrigerator compartment 3 and the vegetable compartment 4 to cool each chamber, and the cooled cold air is returned to the R evaporator 27 again. It is designed to exchange heat.

On the other hand, the freezer compartment 6 and the switching chamber 5 are each partitioned by a heat insulating partition wall 16, the freezer compartment 6 is maintained in a temperature range of −18 to −25 degrees, and the switching chamber 5 has various set temperatures. It is controlled to be held in the belt. On the back surfaces of the switching chamber 5 and the freezer compartment 6, there is provided a freezer compartment cooler 32 (hereinafter referred to as F evaporator), which is a first evaporator whose evaporation temperature is set lower than that of the R evaporator 27, and the upper part thereof. A freezer compartment fan 33 (hereinafter referred to as F fan) is provided.

When the F fan 33 is operated, the cold air generated by the F EVA 32 is supplied to the switching chamber 5 and the freezing chamber 6 to cool each chamber, and the cooled cold air is again heat-exchanged by the F EVA 32. It has become so. Further, the F-eva 32 is provided with a defrost heater 32 'for performing defrosting, and the defrost heater 32' is constituted by a pipe heater, a glass tube heater, or the like.

A machine room 36 is provided at the bottom of the back surface of the main body 1, and a compressor 40, the compressor 40 is provided inside.
A heat radiating fan 38 (hereinafter referred to as C fan) is provided. In addition, a condenser 37 that condenses, for example, refrigerant discharged from the compressor 40 is provided at the front bottom portion of the machine chamber 36. The condenser 37 is, for example, a so-called wire condenser in which a wire is fixed to a refrigerant pipe. Or a so-called spiral capacitor in which fins are spirally wound.

In the refrigeration cycle according to the present invention, as shown in FIG. 3 which is a schematic diagram, a condenser 37 is connected to the discharge side of the compressor 40, and the first capillary tube 34 is connected via a flow rate adjusting device 39.
(Hereinafter referred to as F capillary tube), a pipe connecting F evaporator 32 and accumulator 35 in order, and a pipe connecting second capillary tube 29 (hereinafter referred to as R capillary tube) and R evaporator 27 are connected in parallel. ing.

As will be described later, the outlet side of the F evaporator 32 and the accumulator 35 is connected to the first compression portion 42a of the compressor 40 via the first suction pipe 55, and the outlet side of the R evaporator 27 is connected to the compressor via the second suction pipe 56. 40 cases 41 are connected to each other.

The flow rate adjusting device 39 is a three-way valve that can change the valve opening by rotating the stepping motor to adjust the flow rate of the refrigerant flowing through the F and R evaporators 32 and 27, and can also switch the flow path, fully close, and fully open. It is configured. Note that the flow rate adjusting device 39 is not limited to the above-described configuration, and may use a configuration using a solenoid, and the flow rate control device 39 switches only the flow path even if the flow rates to the F EVA 32 and the R EVA 27 cannot be adjusted. But you can. Furthermore, even if it is not comprised with a single article | item, a several adjustment apparatus may be used and a various change is possible.

Next, a specific configuration of the compressor will be described. As shown in FIG. 4, which is a schematic longitudinal sectional view of the compressor, 41 is a vertical sealed case, and a frame 41 a is attached and fixed to the side wall of the case 41 at a substantially middle portion in the vertical direction in the sealed case 41. ing. The compression part 42 is mounted on the upper side of the frame 41a, and the electric mechanism part 43 is provided on the lower side.

Here, the compression unit 42 employs a so-called reciprocating compressor, and includes a first compression unit 42 a located on the right side of the drawing and a second compression 42 b located on the left side.

A pivot hole is provided at the center of the frame 41a, and a rotation shaft 44 is rotatably provided in the pivot hole. The upper end portion of the rotating shaft 44 is integrally provided with a flange portion 44a mounted on the upper surface of the frame 41a, and the upper portion of the flange portion 44a has a central axis that is eccentric from the central axis of the rotating shaft 44 by a predetermined amount. The eccentric shaft portion 44b is integrally formed.

When the rotary shaft 44 is driven to rotate, the flange portion 44a rotates in a sliding state on the upper surface of the frame 41a,
The eccentric shaft portion 44b rotates eccentrically with respect to the center of the rotation shaft 44.

The first compression part 42a and the second compression part 42b are placed on the upper surface of the frame 41a. Each compression part 42a, 42b is arrange | positioned in the position which opposes substantially 180 degrees via the said eccentric shaft part 44b, and is respectively the cylinder 45a arrange | positioned horizontally with respect to the axial direction.
, 45b.

Inside the cylinders 45a and 45b are compression chambers 47a and 47b in which pistons 46a and 46b are reciprocally accommodated. One ends of connecting rods 48a and 48b are connected to the pistons 46a and 46b, respectively, and the pistons 46a and 46b are connected to the eccentric shaft portion 44b via the connecting rods 48a and 48b.

A spherical portion k is formed at the tips of the connecting rods 48a and 48b, and the pistons 46a and 46b.
Are connected by a ball joint type that engages and holds the ball portion k by a ball receiving portion m formed by caulking. In addition, the sphere part k and the sphere receiving part m may be provided opposite to the connecting rods 48a and 48b and the pistons 46a and 46b, respectively.

The other ends of the connecting rods 48a and 48b form end portions 49a and 49b that are rotatably fitted to the eccentric shaft portion 44b, and have a double-fitting structure with respect to the eccentric shaft portion 44b.

A first suction port 50 a that sucks the refrigerant gas evaporated and vaporized by the F-evapor 32 is provided on the right wall of the first compression portion 42 a and is connected to the first suction pipe 55. A first discharge port 51a for discharging the refrigerant gas compressed by the compression unit 42a is provided in the case 41.

On the other hand, the second suction pipe 56 is directly connected to the case 41, and the inside of the case 41 is R EVA 2.
7 is a mixed gas of the refrigerant gas compressed by the first compression portion 42a and the second wall of the second compression portion 42b has a second suction port 50b for sucking the mixed gas and the compression portion 42b.
Is provided with a discharge port 51b for discharging the refrigerant gas compressed in step 1 to the condenser 37 side.

With respect to such a compression part 42, the electric mechanism part 43 has a frame 41 of the rotating shaft 44.
a rotor 52 fitted to a portion discharged downward from a, and a stator 53 provided with an inner peripheral surface having a narrow gap from the peripheral surface of the rotor 52, and suspended and fixed from the frame 41a by appropriate means, Consists of.

Next, a description will be given of the compression operation of the compressor 40 in a state where the refrigerant flows through both the evaporators 32 and 27 by the operation of the flow control device 39 (hereinafter referred to as a simultaneous cooling mode). When the electric mechanism portion 43 is energized to rotate the rotation shaft 44, the eccentric shaft portion 44b rotates eccentrically, and the pistons 46a, 46b of the first compression portion 42a and the second compression portion 42b respond to this rotation. Reciprocate in the same direction.

Since each compression part 42a, 42b is arrange | positioned in the position which opposes 180 degrees, each piston 46a, 46b makes a mutually reverse process in each compression chamber 47a, 47b.

For example, when the first compression unit 42a performs the suction stroke of sucking the refrigerant gas into the compression chamber 47a in the compression chamber 47a, the second compression unit 42b performs the discharge stroke of discharging the compressed and high pressure gas.

Refrigerant gas (for example, 0.06 MPa) from the F-evapor 32 is sucked into the first compression portion 42a, is increased in pressure by the compression stroke, and is discharged into the case 41. On the other hand, the refrigerant gas (for example, 0.14 MPa) from the R evaporator 27 is sucked into the case 41 via the second suction port 56 and is mixed with the high-pressure refrigerant gas (hereinafter referred to as mixed gas). The inside of the case 41 is R
The intermediate pressure (for example, 0.14 MPa) is almost the same as the refrigerant gas from the evaporator 27. The intermediate-pressure refrigerant gas is sucked into the second compression portion 42b and is increased in pressure by the compression stroke (for example, 0. 0.
5 MPa) and discharged to the condenser 37 side to circulate the refrigeration cycle.

According to such a configuration, in the suction process, the refrigerant gas from the F EVA 32 is introduced into the first compression unit 42a, and the mixed gas is introduced into the second compression unit 42b. The pressure difference between 45b and the inside of the case 41 is maintained at a substantially predetermined value, for example, 0.2 MPa or less, and a large load is not applied to the ball receiving portion m that is a connecting portion, so that the ball portion k is removed. Breakage can be prevented.

The compressor 40 is not limited to the above-described configuration, and a so-called rotary compressor or a first compressor
The refrigerant gas compressed by the compression unit 42a and the refrigerant gas sucked from the R EVA 27 may be directly supplied to the second compression unit 42b and compressed.

Next, the operation of the compressor 40 in cooling the freezer compartment 6 and the like by flowing the refrigerant only in the F EVA 32 (hereinafter referred to as F cooling mode) will be described.

In the case of the F cooling mode, the refrigerant gas from the F EVA 32 is discharged into the suction case 41 in the first compression portion 42a, and therefore the pressure during the suction process in the cylinder 45a is equal to the pressure in the case 41. In the following, a great load is not applied to the ball receiving portion m. On the other hand, the second
In the compression unit 42 b, the refrigerant gas in the case 41 is further compressed and discharged to the condenser 37. For this reason, it does not become lower than the pressure in the case 41, and there is no possibility that the ball joint is damaged.

The refrigerator 1 according to the present embodiment uses at least the simultaneous cooling mode and the F cooling mode described above. As another cooling mode, the refrigerant 1 is compressed for a certain period of time without flowing the refrigerant to both the evaporators 32 and 27 such as pump down. In the fully closed mode in which the machine 42 is operated, the defrost mode in which defrosting is performed by energizing the defrost heater 32 'when the cooling time reaches, for example, 10 hours, and the refrigerating chamber 3 by flowing the refrigerant only in the R evaporator 27. There is an R cooling mode for cooling the.

However, in this R cooling mode, since the refrigerant gas does not flow into the first compression portion 42a, when the compression and suction strokes are repeated, the pressure in the cylinder 45a decreases and eventually becomes a vacuum state. Since the intermediate pressure refrigerant gas that has cooled the R-eva 27 is sucked into the case 41, the pressure difference between the cylinder 45a and the case 41 becomes large, especially after the defrosting of the R-eva 27 and when the power is turned on. In some cases, the pressure difference is a predetermined value (for example, 0) because the refrigerant gas temperature from the R EVA 27 is high.
. 2 MPa) or more. In the suction step in which the load is most applied to the ball receiving portion m, the cylinder 45a is pressed in the direction opposite to the suction direction due to the pressure in the case 41 that is larger than usual, and thus continues to the ball receiving portion m. A lot of load, and eventually loosening occurs,
There is a risk that the ball joint may be damaged, for example, when the ball portion k comes off.

Therefore, in the so-called intermediate pressure compressor 40 that sucks the refrigerant gas from the R evaporator 27 into the case 41, it is preferable not to use the R cooling mode. However, in the low pressure compressor, such a problem is caused. May not be used.

Next, operations in the simultaneous cooling mode and the F cooling mode will be described.
First, in the simultaneous cooling mode, the R fan 28 and the F fan 33 are rotated based on the internal temperature of the refrigerator compartment 3 and the freezer compartment 6 and the target temperature, respectively. Rotate, and if it is low, reduce or stop the number of revolutions.

Further, when the inside temperature of the refrigerator compartment 3 is high, the R evaporator 27 is adjusted by adjusting the flow rate adjusting device 39.
When the flow rate flowing through the storage room is increased and the inside temperature of the refrigerator compartment 3 is low, the flow control device 3
By adjusting 9, the flow rate flowing to the R-eva 27 is reduced. A temperature sensor may be provided on the inlet side and the outlet side of the R EVA 27, and the flow rate adjusting device 39 may be adjusted based on the temperature difference detected by the temperature sensor.

In addition, when the internal temperature of the freezer compartment 6 is increased, the rotation speed of the compressor 40 is increased, and when it is decreased, the rotation speed is decreased. In this case, the maximum number of revolutions of the compressor 40 is, for example, 30 Hz, 12 ° C. to 18 ° C. is 48 when the outside air temperature is 12 ° C. or less because heat leak is small.
Since there are many heat leaks at Hz and 18 ° C. or higher, it is variable according to the outside air temperature of 63 Hz.

Further, the C fan 38 is operated synchronously with the compressor 40, and the rotation speed of the C fan 38 is determined and rotated according to the rotation speed of the compressor 40, and the outside air temperature is low, such as 5 ° C. or less. In this case, it is stopped because it is not necessary to dissipate heat (hereinafter, normal operation).

In this way, the average internal temperature of the refrigerator compartment 3 and the freezer compartment 6 is cooled to the target temperature. According to this simultaneous cooling mode, the refrigerator compartment 3 and the freezer compartment 6 can be cooled at the same time, so that it is not necessary to execute the F cooling mode in terms of internal cooling, but the defrosting heater is added to the R evaporator 27. In the refrigerator such as this embodiment that does not use the refrigerant, the flow of the refrigerant to the R evaporator 27 is stopped and the defrosting operation by the R fan 27 is necessary. Therefore, this mode is executed for a predetermined time, for example, 160 minutes. Then, assuming that the defrosting of the R-eva 27 is necessary, the mode is shifted to the F cooling mode.

In the F cooling mode, the F fan 33 is rotated based on the internal temperature of the freezer compartment 6 and the target temperature. When the internal temperature is high, the F fan 33 is rotated. Lower or stop. Further, the R fan 28 rotates at a low speed to defrost the R EVA 28.

When the internal temperature of the freezer compartment 6 is increased, the rotational speed of the compressor 40 is increased, and when it is decreased, the rotational speed is decreased. In this case, the maximum rotation speed of the compressor 40 varies according to the outside air temperature as in the simultaneous cooling.

In this way, the freezer compartment 6 and the like are cooled so that the average internal temperature becomes the target temperature. When the temperature of the R evaporator 27 reaches a predetermined temperature, for example, 3 ° C. or higher, defrosting is performed. Assuming that it has been completed, it shifts to the simultaneous cooling mode. If the operation time in the F cooling mode is too long, the temperature of the refrigerator compartment 3 or the like may increase too much. Therefore, after operating for a maximum time, for example, 120 minutes, the mode may be shifted to the simultaneous cooling mode. .

Next, rotation control of the C fan 38 during the F cooling mode will be described. During the F cooling mode, heat radiation of the condenser 37 by the C fan 38 is suppressed more than in the simultaneous cooling mode.

Specifically, as shown in FIG. 1 which is a flowchart showing a rotation control method of the C fan 38, first, in step 1, it is detected whether or not the F cooling mode is in effect (S1), and the F cooling mode must be in effect. If it is in the simultaneous cooling mode, the process proceeds to step 2, and the C fan 38 is
The normal operation is executed (S2). On the other hand, if it is in F cooling mode, it will progress to Step 3.

In step 3, it is detected whether or not the compressor 40 is rotating at the maximum number of rotations (S3). If it is rotating at the maximum number of rotations, the process proceeds to step 4 and the C fan 38 is rotated in the reverse direction (S4). If it is not rotating at the maximum number of rotations, the process proceeds to step 5, and the C fan 38 is stopped or rotated at a lower speed than in the normal operation (S5).

In this way, during the F cooling mode, the heat radiation of the condenser 37 by the C fan 38 is suppressed more than in the simultaneous cooling mode. The reason will be described below.

As shown in FIG. 3, the applicant causes the refrigerator using the above-described refrigeration cycle to execute the simultaneous cooling mode and the F cooling mode while keeping the C fan under normal control under an outside air temperature of 30 ° C. A sight glass S was installed on the inlet side of the flow control device 39, and the flow of the refrigerant was observed.

As a result, liquid refrigerant was flowing in the simultaneous cooling mode, but in the F cooling mode, almost no liquid refrigerant flow was observed, and it was confirmed that vaporized refrigerant was flowing. That is, on the inlet side of the flow control device 39, the high-temperature and high-pressure gas should have been radiated and condensed by the condenser 37 or the like, so liquid refrigerant usually flows, but vaporized refrigerant flows. This means that the liquid refrigerant does not flow through the F EVA 33, so that the cooling performance cannot be maintained and the cooling is insufficient.

As a factor of this phenomenon, in the simultaneous cooling mode, F compressed by the first compression unit 42a is used.
The refrigerant gas of the evaporator 32 and the refrigerant gas of the R evaporator 27 are compressed by the second compression unit 42b and the condenser 3
7, the amount of circulating refrigerant is large, whereas in the F cooling mode, the F
Since only the refrigerant gas is compressed by the compressor 40 and discharged to the condenser 37, the amount of circulating refrigerant is reduced, so that it is considered that the heat radiation in the condenser 37 becomes excessive. That is, in the condenser 37, the ratio of the liquid refrigerant is increased, and the amount of circulating refrigerant flowing through the F-evapor 32 is remarkably reduced, so that it can be estimated that insufficient cooling occurs.

Therefore, in the present invention, during the F cooling mode, the heat radiation of the condenser 37 by the C fan 38 is suppressed. Specifically, the C fan 38 is stopped, rotated at a low speed, or rotated in the reverse direction, thereby causing an excessive condenser. By preventing the heat radiation of 37 and securing an appropriate amount of circulating refrigerant, it is possible to eliminate the lack of cooling.

Furthermore, the applicant conducted a similar experiment by appropriately changing the rotation speed of the compressor. As the rotation speed of the compressor 40 increased, the vaporized refrigerant flowed on the inlet side of the flow rate control device 39. It was confirmed that the ratio is higher.

As a factor of this phenomenon, when the rotational speed of the compressor 40 increases, the F capillary tube 3
4 also increases the resistance of the liquid refrigerant flowing to the liquid refrigerant 4, so that the liquid refrigerant that is difficult to flow is likely to stay on the upstream side of the condenser 37 and the like.

Therefore, in Steps 3 and 4, when the compressor 40 is rotating at the maximum rotational speed, the C fan 38 is reversely rotated to blow air radiated from the compressor 40 onto the condenser 37, thereby causing the C fan 38 to rotate. Since the heat radiation of the condenser 37 can be suppressed more than when the engine is stopped or rotated at a low speed, it is possible to reliably secure an appropriate amount of circulating refrigerant and eliminate the lack of cooling.

Next, another embodiment will be described. In the present embodiment, as shown in FIGS.
An inlet temperature sensor 60 and an outlet temperature sensor 61 are provided on the inlet side and the outlet side of the EVA 32, respectively, and the rotation control of the C fan 38 is performed based on the temperature difference detected by the temperature sensors 60 and 61. is there.

That is, as described above, when the heat radiation of the condenser 37 is excessive, the F EVA 32
Since no liquid refrigerant is flowing through the inlet, the temperature difference between the inlet side and the outlet side increases. Therefore, when the detected temperature difference between the inlet temperature sensor 60 and the outlet temperature sensor 61 is a predetermined temperature difference, for example, 4 ° C. or more, it is considered that the heat radiation of the condenser 37 by the C fan 38 is excessive, and C The fan 38 is stopped, rotated at a low speed, and reversely rotated.

In this case, for example, when the temperature difference is larger, such as 6 ° C. or more, the C fan 38 is reversely rotated or stopped in the range of 4 ° C. to 6 ° C., and the rotation control is performed on the C fan 38 according to the temperature difference. You may go. Further, in the present embodiment, since it is possible to directly detect the insufficient cooling of the F-evapor 32, the process may be executed during the simultaneous cooling mode regardless of the F cooling mode. Further, the rotation control of the C fan 38 may be performed according to the rotational speed of the compressor 40 as in step 3.

According to the above configuration, inadequate cooling of the F-evapor 32 is directly detected and the rotation of the C fan 38 is controlled. The amount of refrigerant can be ensured, thereby eliminating the lack of cooling.

The present invention can prevent insufficient cooling during the F cooling mode, and can be applied to various refrigerators equipped with a two-stage compressor.

It is a flowchart which shows the rotation control method of C fan of this invention. It is a longitudinal cross-sectional view which shows the refrigerator of this invention. It is the schematic which shows the refrigerating cycle of this invention. It is a longitudinal cross-sectional view which shows the compressor of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Refrigerator main body 3 ... Refrigeration room 6 ... Freezer room 27 ... R Eva 28 ... R Fan 32 ... F Eve 33 ... F Fan 37 ... Condenser 38 ... C Fan 39 ... Flow control device 40 ... Compressor 41 ... Case 42 ... Compression part 42a ... 1st compression part 42b ... 2nd compression part 60 ... Inlet temperature sensor 61 ... Outlet temperature sensor S ... Cytoglass

Claims (5)

A refrigerator main body filled with a heat insulating material between the outer box and the inner box, a first evaporator and a second evaporator disposed in the refrigerator main body and having different evaporation temperatures, and the first evaporator or the second evaporation A flow rate adjusting device that varies the flow rate of the refrigerant flowing through the container, a first compression unit, and a second compression unit, wherein the first compression unit is the first
The refrigerant gas evaporated by the evaporator is compressed, and the second compression unit and the refrigerant gas evaporated by the second evaporator
A compressor that compresses the refrigerant gas discharged from the compressor and discharges it outside the case, a condenser that condenses the refrigerant discharged by the compressor, a heat radiating fan that radiates heat from the condenser, and the flow control device And a control means for switching between at least a first cooling mode in which the refrigerant flows through the first evaporator and the second evaporator and a second cooling mode in which the refrigerant flows only through the first evaporator. In the second cooling mode, the heat radiation of the condenser by the heat radiating fan is suppressed more than in the first cooling mode. 2. The refrigerator according to claim 1, wherein in the second cooling mode, when the heat dissipating fan is rotated, it is rotated at a low speed. The refrigerator according to claim 1, wherein the heat dissipating fan is not rotated in the second cooling mode. The refrigerator according to claim 1, wherein in the second cooling mode, the heat dissipating fan is reversely rotated. The refrigerator according to claim 1, wherein in the second cooling mode at a high rotation speed of the compressor, the heat dissipating fan is rotated in the reverse direction.

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