CN104160224A - Refrigerator - Google Patents

Abstract

Including at least a refrigeration cycle with a compressor (19), an evaporator (20), and a condenser (21), a main condenser (21) with forced air cooling, and a flow stream connected to the downstream side of the main condenser (21) A channel switching valve (40), and a plurality of anti-dew pipes (44, 41) provided on the downstream side of the channel switching valve (40). When the refrigerating cycle operates under normal conditions, the refrigerant flows alternately through the multiple anti-dew pipes (44, 41), and when it operates under overload conditions, the refrigerant flows through the multiple anti-dew pipes (44, 41) in parallel. ).

Description

Cold storage

technical field

The present invention relates to a refrigerator in which efficiency of a refrigeration cycle is improved by having a damper for blocking cold air in a freezer compartment and a refrigerator compartment, and cooling the freezer compartment and the refrigerator compartment individually using one evaporator.

Background technique

From the viewpoint of energy saving, among domestic refrigerators, there is a refrigerator in which efficiency of a refrigeration cycle is improved by cooling a freezer compartment and a refrigerator compartment individually using one evaporator. This is to improve the efficiency of the refrigeration cycle by cooling at a higher evaporating temperature than the freezer when cooling the refrigerator where the air temperature is higher.

In addition, it has been proposed to cool the refrigerating room by cooling and heating of the low-temperature evaporator when the compressor is stopped, using dampers provided for blocking cold air in the freezing room and the refrigerating room respectively (for example, refer to Patent Document 1). This is to achieve energy saving by reusing the heat of sublimation or melting heat of frost adhering to the evaporator, reducing heater power during defrosting, and reducing the operation rate of the refrigeration cycle required to cool the refrigerator compartment.

Next, a conventional refrigerator will be described with reference to the drawings.

Fig. 5 is a longitudinal sectional view of a conventional refrigerator, Fig. 6 is a structural diagram of a refrigeration cycle of a conventional refrigerator, Fig. 7 is a schematic diagram of a front of a conventional refrigerator, and Fig. 8 shows a diagram of a conventional refrigerator. Diagram of the state transition of cooling control and its switching conditions.

In FIGS. 5 to 7 , refrigerator 11 has housing 12 , door 13 , feet 14 supporting housing 12 , lower machine compartment 15 disposed at the bottom of housing 12 , refrigerator compartment 17 disposed at the top of housing 12 and The freezer compartment 18 is arranged in the lower part of the casing 12 . In addition, refrigerator 11 includes compressor 56 housed in lower machine compartment 15 , evaporator 20 housed in the back side of freezer compartment 18 , and main condenser housed in lower machine room 15 as components constituting a refrigeration cycle. twenty one. In addition, refrigerator 11 has partition wall 22 for partitioning lower machine room 15, fan 23 attached to partition wall 22 for air cooling main condenser 21, evaporator pan 57 provided above compressor 56, and the lower machine room. The bottom plate 25 of 15.

In addition, refrigerator 11 has a plurality of intake ports 26 provided on bottom plate 25 , discharge ports 27 provided on the rear side of lower machine compartment 15 , and an outlet for connecting discharge ports 27 of lower machine compartment 15 to the upper portion of housing 12 . Connected to the airway 28. Here, the lower machine room 15 is divided into two rooms by the partition wall 22, and the main condenser 21 is accommodated on the windward side of the fan 23, and the compressor 56 and the evaporator 57 are accommodated on the leeward side.

In addition, in the refrigerator 11, as a component constituting the refrigeration cycle, there is a dew prevention pipe 37 located on the downstream side of the main condenser 21 and thermally bonded to the outer surface of the casing 12 around the opening of the freezer compartment 18; On the downstream side of the pipe 37, there is a drier 38 that dries the circulating refrigerant; and an orifice 39 that connects the drier 38 and the evaporator 20 and depressurizes the circulating refrigerant.

In addition, refrigerator 11 has evaporator fan 50 for supplying cool air generated by evaporator 20 to refrigerator compartment 17 and freezer compartment 18 , freezer damper 51 for blocking cool air supplied to freezer compartment 18 , and a freezer compartment damper 51 for blocking cool air supplied to refrigerator compartment 17 . The damper 52 of the refrigerator compartment. Further, refrigerator 11 has a duct 53 for supplying cold air to refrigerator compartment 17, an FCC temperature sensor 54 for detecting the temperature of freezer compartment 18, a PCC temperature sensor 55 for detecting the temperature of refrigerator compartment 17, and a sensor for detecting the temperature of evaporator 20. DEF temperature sensor 58 .

Next, the operation|movement of the conventional refrigerator comprised as mentioned above is demonstrated.

Conditions M1 to M11 in FIG. 8 represent mode switching in cooling control of a conventional refrigerator.

It starts from the cooling stop state in which the fan 23, the compressor 56, and the evaporator fan 50 are all stopped (hereinafter, this operation is referred to as "off (OFF) mode"). In the "stop mode", the temperature detected by the FCC temperature sensor 54 rises to a predetermined FCC_ON temperature, or the temperature detected by the PCC temperature sensor 55 rises to a predetermined PCC_ON temperature (that is, condition M1 is satisfied). At this time, the freezer compartment damper 51 is closed, the refrigerator compartment damper 52 is opened, and the compressor 56, fan 23, and evaporator fan 50 are driven (hereinafter, this operation is referred to as "PC cooling mode").

In the "PC cooling mode", the fan 23 drives the main condenser 21 side of the lower machine room 15 partitioned by the partition wall 22 to form a negative pressure, and the external air is sucked from the plurality of suction ports 26, and the compressor 56 and The side of the evaporator 57 is formed into a positive pressure, and the air in the lower machine compartment 15 is discharged to the outside through the plurality of discharge ports 27 .

On the other hand, the refrigerant discharged from the compressor 56 exchanges heat with the outside air in the main condenser 21 and condenses a part of the remaining gas, and then is supplied to the anti-dew pipe 37 . The refrigerant passing through the anti-dew pipe 37 warms the opening of the freezer compartment 18 and radiates heat to the outside through the casing 12 to condense. The liquid refrigerant passing through the anti-dew pipe 37 is dehydrated in the drier 38, decompressed by the throttling member 39, evaporates in the evaporator 20 and exchanges heat with the air in the refrigerator compartment 17 to cool the refrigerator compartment 17, And return to the compressor 56 as gas refrigerant.

In the "PC cooling mode", when the detection temperature of the FCC temperature sensor 54 drops to the FCC_OFF temperature of the predetermined value and the detection temperature of the PCC temperature sensor 55 falls to the PCC_OFF temperature of the predetermined value (that is, the condition M2 is satisfied), the transition to the "Stop" mode is performed. model".

Also, in the "PC cooling mode", the detected temperature of the FCC temperature sensor 54 shows a temperature higher than the prescribed FCC_OFF temperature and the detected temperature of the PCC temperature sensor 55 drops to the prescribed PCC_OFF temperature (ie, the condition M5 is satisfied). At this time, the freezer door 51 is opened, the refrigerator door 52 is closed, and the compressor 56, the fan 23 and the evaporator fan 50 are driven. Hereinafter, freezer compartment 18 is cooled by exchanging heat between the air in freezer compartment 18 and evaporator 20 by operating the refrigeration cycle similarly to PC cooling (hereinafter, this operation is referred to as "FC cooling mode").

In the "FC cooling mode", when the detection temperature of the FCC temperature sensor 54 drops to the FCC_OFF temperature of the predetermined value and the detection temperature of the PCC temperature sensor 55 shows the PCC_ON temperature or higher of the predetermined value (that is, the condition M6 is satisfied), the transition to the PC cooling mode is performed. .

In addition, in the "FC cooling mode", when the detected temperature of the FCC temperature sensor 54 drops to the FCC_OFF temperature of the predetermined value and the detected temperature of the PCC temperature sensor 55 shows a temperature lower than the PCC_ON temperature of the predetermined value (that is, the condition M4 is satisfied), Migrate to stop mode.

Next, the cooling operation using the frost adhering to the evaporator 20 will be described.

The defrosting heater (not shown) near the evaporator 20 is energized, the compressor 56 is stopped, the freezer compartment damper 51 is closed, the refrigerator compartment damper 52 is opened, and the evaporator fan 50 is driven (hereinafter, this action is referred to as is the “defrosting mode”), thereby melting and removing the frost adhering to the evaporator 20, and using the heat of sublimation or melting heat of the gradually removed frost to cool the refrigerator compartment 17.

In addition, the defrosting heater (not shown) provided near the evaporator 20 is not energized, the compressor 56 is stopped, the freezer compartment damper 51 is closed, the refrigerating compartment damper 52 is opened, and the evaporator fan 50 is driven (hereinafter referred to as This operation is referred to as “stop cycle cooling mode”), whereby refrigerating compartment 17 is cooled by evaporator 20 and low-temperature sensible heat of frost adhering to evaporator 20 and heat of sublimation or melting of frost. At this time, the frost adhering to the evaporator 20 is not completely melted away, and by reusing the frost adhering to the evaporator 20, the power of the heater (not shown) in the "defrosting mode" can be reduced and the refrigerator compartment 17 can be cooled. .

In the "FC cooling mode", when the power is turned on, or when a predetermined time Tx2 has elapsed from the end of the previous defrosting (that is, when the condition M7 is satisfied), the FC cooling is continued for a predetermined period in order to cool the freezer compartment 18 to a temperature lower than normal. time (hereinafter, this operation is referred to as "pre-cooling mode"). Next, when the predetermined time Tx3 has elapsed from the start of pre-cooling (that is, the condition M8 is satisfied), the operation shifts to the defrosting operation. Also, during defrosting, when the detected temperature of the DEF temperature sensor 58 attached to the evaporator 20 shows a temperature higher than the DEF_OFF temperature of a predetermined value, or when a predetermined time Tx4 has elapsed from the start of defrosting (that is, the condition M9 is satisfied), the transition to " Stop Recirculating Cooling Mode".

In addition, in the "stop mode", when the predetermined time Tm has elapsed from OFF (that is, the condition M10 is satisfied), the transition is made to the "stop circulation cooling mode".

In the "off-circulation cooling mode", when a predetermined time Td elapses from the start of the off-circulation cooling (that is, when the condition M11 is satisfied), the state transitions to the "off-circulation mode".

Here, the cooling operation under the overload condition will be described.

In the conventional refrigerator, cooling control is performed by switching between the PC cooling that cools the refrigerator compartment 17 and the FC cooling that cools the freezer compartment 18 alone. When the load is high, one of the refrigerator compartment 17 or the freezer compartment 18 may not be cooled for a long time.

Then, a description will be given of the case where the detected temperature of the FCC temperature sensor 54 exceeds the FCC_ON temperature of a predetermined value in the "PC cooling mode" as indicated by the condition M5, or in the case of the "FC cooling mode" as indicated by the condition M6. In the case where the temperature detected by the PCC temperature sensor 55 exceeds the PCC_ON temperature which is a predetermined value. At this time, until the PCC_OFF temperature at which the temperature detected by the PCC temperature sensor 55 reaches a predetermined value or the FCC_OFF temperature at which the temperature detected by the FCC temperature sensor 54 reaches a predetermined value, PC cooling for a predetermined time Txr and FC cooling for a predetermined time Txf are alternately repeated ( Hereinafter, this operation is referred to as "alternate cooling"). Thereby, the state in which one of the refrigerator compartment 17 or the freezer compartment 18 has not been cooled for a long time can be avoided.

Through the operation described above, the efficiency of the refrigeration cycle can be improved by keeping the temperature of the evaporator 20 higher in the "PC cooling mode" than in the "FC cooling mode". In addition, by reusing the latent heat of melting of the frost adhering to the evaporator 20 in the "stop cycle cooling mode", it is possible to reduce the heater power (not shown) at the time of defrosting and reduce the refrigeration cycle required for cooling the refrigerator compartment 17. The operating rate can achieve energy saving.

However, in the structure of the existing refrigerator, the refrigerant always flows in the anti-dew pipe 37 without being affected by the installation environment and operating state of the refrigerator, so the thermal load that invades the freezer compartment 18 from the anti-dew pipe 37 is caused, This causes the power consumption of the refrigerator to increase.

In addition, the anti-dew pipe 37 made of a long thin-diameter pipe has a large pressure loss, and it becomes a main cause of an increase in the condensation temperature in an overload condition in which the circulation amount of the refrigerant is increased, and an increase in the power consumption of the refrigerator. .

Therefore, it is a subject to suppress pressure loss and thermal load due to the dew prevention pipe depending on the installation environment and operating state of the refrigerator.

Prior art literature

patent documents

Patent Document 1: Japanese Patent Application Laid-Open No. 9-236369

Contents of the invention

In the refrigerator of the present invention, a plurality of anti-dew pipes are connected in parallel (in parallel) via a flow path switching valve on the downstream side of the main condenser.

Thereby, especially at the time of overload with a large refrigerant circulation amount, a plurality of anti-dew pipes are used in parallel, and pressure loss due to the anti-dew pipes can be suppressed. The time of overload means, for example, when the door is frequently opened and closed in summer when the outside air temperature and humidity are high, or when food with a high temperature is stored. At this time, the operation rate of the refrigeration cycle increases, the refrigerant circulation amount increases, and it is necessary to prevent dew condensation around the refrigerator casing in which the dew prevention pipe is arranged. At this time, by using the anti-dew pipes in parallel to reduce the circulation amount of the refrigerant per one, the pressure loss caused by the anti-dew pipes can be suppressed.

Description of drawings

Fig. 1 is a longitudinal sectional view of a refrigerator according to a first embodiment of the present invention.

Fig. 2 is a cycle configuration diagram of the refrigerator according to the first embodiment of the present invention.

Fig. 3 is a schematic view of the back of the refrigerator according to the first embodiment of the present invention.

4 is a diagram showing state transitions and switching conditions of cooling control in the refrigerator according to the first embodiment of the present invention.

Fig. 5 is a longitudinal sectional view of a conventional refrigerator.

Fig. 6 is a cycle configuration diagram of a conventional refrigerator.

Fig. 7 is a schematic diagram of the front of a conventional refrigerator.

Fig. 8 is a diagram showing state transitions and switching conditions of cooling control in a conventional refrigerator.

Detailed ways

Hereinafter, embodiments of the present invention will be described with reference to the drawings, and the same reference numerals will be used for the same structures as the conventional examples, and detailed description thereof will be omitted. In addition, this invention is not limited to this embodiment.

(first embodiment)

Fig. 1 is a longitudinal sectional view of a refrigerator according to a first embodiment of the present invention, Fig. 2 is a diagram showing a circulation structure of the refrigerator according to the first embodiment of the present invention, and Fig. 3 is a view of the refrigerator according to the first embodiment of the present invention. As a schematic view of the back, FIG. 4 is a diagram showing state transition and switching conditions of the cooling control of the refrigerator according to the first embodiment of the present invention.

In FIGS. 1 to 3 , the refrigerator 11 has a housing 12 , a door 13 , a leg 14 supporting the housing 12 , a lower machine room 15 provided at the bottom of the housing 12 , and an upper machine room provided at the top of the housing 12 . 16. A refrigerating chamber 17 arranged on the upper part of the casing 12 and a freezing chamber 18 arranged on the lower part of the casing 12 . In addition, refrigerator 11 has compressor 19 housed in upper machine compartment 16 , evaporator 20 housed in the back side of freezer compartment 18 , and main condenser housed in lower machine room 15 as components constituting a refrigeration cycle. twenty one. In addition, refrigerator 11 has partition wall 22 for partitioning lower machine compartment 15, fan 23 for air cooling main condenser 21 attached to partition wall 22, evaporator pan 24 installed on the leeward side of partition wall 22, and a lower mechanical compartment. The floor 25 of the chamber 15.

Here, the compressor 19 is a variable-speed compressor, and uses six stages of rotation speeds selected from 20 to 80 rps. This is to avoid resonance of piping and the like, and to adjust the refrigerating capacity by switching the rotation speed of the compressor 19 in six stages from low speed to high speed. The compressor 19 operates at a low speed at the time of start-up, and the operation time for cooling the refrigerator compartment 17 or the freezer compartment 18 becomes longer, thereby increasing the speed. This is because a low speed with the highest efficiency is mainly used, and an appropriate higher rotational speed is used for an increase in the load of the refrigerator compartment 17 or freezer compartment 18 due to high outside air temperature, door opening and closing, and the like. At this time, the rotation speed of the compressor 19 is controlled independently of the cooling operation mode of the refrigerator 11, but it is also possible to set the rotation speed at the start of the "PC cooling mode" with a high evaporation temperature and a large freezing capacity to be lower than that of the "PC cooling mode". FC Cooling Mode". In addition, as the temperature of refrigerator compartment 17 or freezer compartment 18 decreases, the freezing capacity may be adjusted so that compressor 19 may be decelerated.

In addition, refrigerator 11 has a plurality of intake ports 26 provided on bottom plate 25 , discharge ports 27 provided on the rear side of lower machine compartment 15 , and a connection connecting discharge ports 27 of lower machine compartment 15 and upper machine compartment 16 . Ventilation Road 28. Here, the lower machine room 15 is divided into two rooms by the partition wall 22, and the main condenser 21 is accommodated on the windward side of the fan 23, and the evaporator 24 is accommodated on the leeward side.

In addition, in the refrigerator 11, as a component constituting the refrigeration cycle, there is a first anti-dew pipe 44 located on the downstream side of the main condenser 21 and thermally bonded to the outer surface of the casing 12 around the opening of the freezer compartment 18; On the downstream side of the first anti-dew pipe 44, there is a drier 38 for drying the circulating refrigerant; and an orifice 39 for decompressing the circulating refrigerant by connecting the drier 38 and the evaporator 20 .

Here, in order to branch the refrigerant flow path of the first anti-dew pipe 44 , a flow path switching valve 40 , a second anti-dew pipe 41 , and a junction 42 are provided. The first anti-dew pipe 44 and the second anti-dew pipe 41 are connected in parallel to the flow path switching valve 40 and the confluence point 42, and the flow path switching valve 40 can open and close the first anti-dew pipe 44 and the second anti-dew pipe 41 respectively. separate flow of refrigerant. In addition, the second anti-dew pipe 41 has approximately the same internal volume and heat dissipation capacity as the first anti-dew pipe 44, and is in contact with the back surface of the housing 12 to dissipate heat. Heat transfer inside the body 12.

In addition, refrigerator 11 has evaporator fan 30 for supplying cold air generated by evaporator 20 to refrigerator compartment 17 and freezer compartment 18 , freezer compartment damper 31 for blocking cold air supplied to freezer compartment 18 , and a fan for blocking supply to refrigerator compartment 17 . Air-conditioning refrigerator compartment damper 32. In addition, refrigerator 11 has duct 33 for supplying cool air to refrigerator compartment 17 , an FCC temperature sensor 34 for detecting the temperature of freezer compartment 18 , a PCC temperature sensor 35 for detecting the temperature of refrigerator compartment 17 , and a DEF temperature sensor for detecting the temperature of evaporator 20 . 36. Here, the duct 33 is formed along the adjacent wall surface of the refrigerating room 17 and the upper machine room 16, and part of the cold air passing through the duct 33 is discharged from the vicinity of the center of the refrigerating room, and most of the cold air cools the adjacent wall surface of the upper machine room 16 and is After passing through, it is discharged from the upper part of the refrigerator compartment 17 .

Next, the operation|movement of the refrigerator which concerns on 1st Embodiment of this invention comprised as mentioned above is demonstrated.

In FIG. 4, conditions L1-L15 represent the mode switching of the cooling control of the refrigerator in 1st Embodiment of this invention. Here, detailed descriptions of the same cooling operation modes and mode switching conditions as those of conventional refrigerators are omitted.

First, the "stop circulation cooling mode" will be described.

In the "stop mode", when the condition L10 (that is, the condition M10) is satisfied, the mode shifts to the "stop circulation cooling mode".

Then, in the "stop circulation cooling mode", when the condition L1 is satisfied (that is, the condition M1) or the detected temperature of the DEF temperature sensor 36 rises to a predetermined value of the OSR_OFF temperature (that is, the condition L11 is satisfied), the transition to the "stop mode" .

Thereby, it is possible to appropriately adjust the time of "stop circulation cooling mode" using the DEF temperature sensor 36 provided in the evaporator 20 . In conventional refrigerators, there is a possibility that the temperature of the evaporator 20 rises above the required temperature in order to always stop the cycle cooling for a certain time Td, and transfer heat to the adjacent freezer compartment 18, thereby increasing the heat load. The OSR_OFF temperature, which is the reference temperature for ending the "stop circulation cooling mode", is preferably set to about -15 to -5°C. If the temperature is lower than -15°C, the effect of stop cycle cooling cannot be obtained sufficiently, and if it exceeds -5°C, the thermal load on the freezer compartment 18 may increase.

Next, the cooling operation under normal conditions will be described.

In the "PC cooling mode", when the detected temperature of the FCC temperature sensor 34 shows a temperature higher than the FCC_OFF temperature of the specified value, and the detected temperature of the PCC temperature sensor 35 drops to the PCC_OFF temperature of the specified value (that is, the condition L5 is satisfied), transition to FC cooling mode. In addition, as indicated by the condition L5, in the PC cooling mode, after a predetermined time Tx1 has elapsed, the difference between the temperature detected by the FCC temperature sensor 34 and the FCC_OFF temperature of a predetermined value is equal to the temperature detected by the PCC temperature sensor 35 and the PCC_OFF temperature of a predetermined value. When the difference is the same or more, it will shift to "FC cooling mode".

In the "FC cooling mode", the refrigerant discharged from the compressor 19 exchanges heat with the outside air in the main condenser 21 and condenses with a part of the gas remaining, and then flows to the first anti-dew pipe 44 or the second anti-dew pipe 44 through the flow path switching valve 40 . Anti-dew pipe 41 supply. At this time, the flow path switching valve 40 is controlled to alternately supply the refrigerant to any one of the first anti-dew pipe 44 and the second anti-dew pipe 41 . As a result, the amount of heat load that intrudes into freezer compartment 18 from first dew prevention pipe 44 through the opening of freezer compartment 18 can be reduced.

Afterwards, the liquid refrigerant after passing through the confluence point 42 removes moisture in the drier 38 in the same manner as in the prior art, depressurizes by the throttling member 39, evaporates in the evaporator 20, and exchanges heat with the air in the refrigerator compartment 17. , cools the refrigerator compartment 17, and returns to the compressor 19 as gas refrigerant.

In addition, the first anti-dew pipe 44 and the second anti-dew pipe 41 have substantially the same internal volume and heat dissipation capacity, so the amount of liquid refrigerant held in the non-use state is equal to the heat dissipation amount in the use state, and can be replaced with switching. Cooling is efficiently performed without a large change in the cooling state.

In the "FC cooling mode", when the detected temperature of the FCC temperature sensor 34 drops to the FCC_OFF temperature of the specified value and the detected temperature of the PCC temperature sensor 35 shows the PCC_ON temperature or higher of the specified value (that is, condition L6 is satisfied), the transition to the "PC cooling mode" is performed. model". In addition, as indicated by the condition L6, in the "FC cooling mode", after the lapse of the predetermined time Tx1, the difference between the temperature detected by the FCC temperature sensor 34 and the FCC_OFF temperature of the predetermined value reaches the difference between the temperature detected by the PCC temperature sensor 35 and the predetermined value. When the PCC_OFF temperature difference is equal to or less, it transitions to "PC cooling mode".

In the "PC cooling mode", the refrigerant discharged from the compressor 19 exchanges heat with the outside air in the main condenser 21 and condenses a part of the gas, and then flows through the flow path switching valve 40 to the first anti-dew pipe 44 or the second anti-dew pipe 44 . Anti-dew pipe 41 supply. At this time, the flow path switching valve 40 is controlled to alternately supply the refrigerant to any one of the first anti-dew pipe 44 and the second anti-dew pipe 41 . As a result, the amount of heat load that intrudes into freezer compartment 18 from first dew prevention pipe 44 through the opening of freezer compartment 18 can be reduced.

Afterwards, the liquid refrigerant after passing through the confluence point 42 removes moisture in the drier 38 in the same manner as in the prior art, depressurizes by the throttling member 39, evaporates in the evaporator 20, and exchanges heat with the air in the refrigerator compartment 17. , cools the refrigerator compartment 17, and returns to the compressor 19 as gas refrigerant.

In addition, the first anti-dew pipe 44 and the second anti-dew pipe 41 have substantially the same internal volume and heat dissipation capacity, so the amount of liquid refrigerant held in the non-use state is equal to the heat dissipation amount in the use state, and can be replaced with switching. Cooling is efficiently performed without a large change in the cooling state. In addition, in the "PC cooling mode", cool air does not flow into the freezer compartment 18, and the temperature in the freezer compartment 18 is relatively higher than that in the "FC cooling mode", so the use ratio of the first anti-dew pipe 44 can be suppressed to be lower than that in the "FC cooling mode". FC Cooling Mode" Medium Low.

Next, the cooling operation under the overload condition will be described.

By controlling the normal conditions as described above, in an overload condition such as when the refrigerator compartment 17 and the freezer compartment 18 are both at high temperature when the power is turned on, the "PC cooling mode" and the "FC cooling mode" can be alternately switched every predetermined time Tx1 and Priority is given to cooling where the difference between the OFF temperature and the OFF temperature which is a reference to end the cooling is greater. As a result, it is possible to more flexibly allocate the cooling operation time compared to the time-fixed alternating cooling implemented in the conventional refrigerator.

However, even if alternate cooling is performed with a degree of freedom in the cooling operation time, since the cooling of the freezer compartment 18 is performed intermittently, the upper limit of the storage temperature of frozen foods such as ice cream may be exceeded. Therefore, an operation of simultaneously cooling refrigerator compartment 17 and freezer compartment 18 is added only in an overload condition (hereinafter, this operation is referred to as "simultaneous cooling mode").

"Simultaneous cooling mode" refers to opening the freezer door 31, opening the refrigerator door 32, and driving the compressor 19, the fan 23, and the evaporator fan 30. In the "simultaneous cooling mode", by driving the fan 23, the main condenser 21 side of the lower machine room 15 partitioned by the partition wall 22 is formed into a negative pressure, and external air is sucked from the plurality of suction ports 26, and the compressor 19 and The side of the evaporator 57 is formed into a positive pressure, and the air in the lower machine compartment 15 is discharged to the outside through the plurality of discharge ports 27 .

On the other hand, the refrigerant discharged from the compressor 19 exchanges heat with the outside air in the main condenser 21 and condenses a part of the gas, and then flows through the flow path switching valve 40 to the first anti-dew pipe 44 or the second anti-dew pipe. 41 supplies. At this time, the flow path switching valve 40 is controlled, and the refrigerant is simultaneously supplied to both the first anti-dew pipe 44 and the second anti-dew pipe 41 . As a result, the pressure loss caused by the first anti-dew pipe 44 and the second anti-dew pipe 41 can be suppressed by reducing the refrigerant circulation amount per one pipe.

Afterwards, the liquid refrigerant after passing through the confluence point 42 removes moisture in the drier 38 in the same manner as in the prior art, depressurizes by the throttling member 39, evaporates in the evaporator 20, and is combined with the refrigerator compartment 17 and the freezer compartment 18. The internal air performs heat exchange, cools the refrigerating chamber 17 and the freezing chamber 18, and returns to the compressor 19 as a gas refrigerant.

At this time, the evaporator fan 30 is rotated at a high speed to ensure the air volume necessary for cooling the refrigerator compartment 17 and the freezer compartment 18 in parallel. As a result, compared with the "FC cooling mode", air formed at a high temperature and at a high wind speed flows into the evaporator 20, thereby increasing the temperature of the blown air from the evaporator 20, so it is preferable to operate the compressor at a relatively high speed. Machine 19, ensuring proper freezing capacity. In the "simultaneous cooling mode", if the compressor 19 is operated at a low speed, the temperature of the blown air from the evaporator 20 may rise and the freezer compartment 18 may not be cooled to a low temperature.

Therefore, in the "PC cooling mode", when the rotation speed of the compressor 19 is equal to or higher than the predetermined rotation speed (that is, the condition L12 is satisfied), the transition to the "simultaneous cooling mode" is performed, and in the "simultaneous cooling mode", the rotation speed of the compressor 19 is low. At a predetermined rotation speed (that is, when the condition L13 is satisfied), it transitions to the "PC cooling mode". In addition, the mode switching of the condition L12 and the condition L13 is performed prior to other state transitions. This is because, when the rotational speed of the compressor 19 is increased to a predetermined rotational speed or higher, it is detected that the refrigerator 11 is in an overload condition, and the transition to the "simultaneous cooling mode" is performed, and the evaporator 20 is avoided when the rotational speed of the compressor 19 is lower than the predetermined rotational speed. The temperature of the blown air rises and the freezer compartment 18 cannot be cooled to a low temperature.

In addition, in the "simultaneous cooling mode", the temperature detected by the PCC temperature sensor 35 falls below the PCC_OFF temperature which is a predetermined value or the FCC_LIM temperature which is a predetermined value higher than the FCC_ON temperature is detected by the temperature detected by the FCC temperature sensor 34 after a predetermined time Tx5 elapses ( That is, when the condition L14) is satisfied, it transitions to "FC cooling mode". This is because the simultaneous cooling mode is continued up to the allowable temperature upper limit of the freezer compartment 18 in order to suppress the temperature rise of the uncooled refrigerator compartment 17 in the "FC cooling mode". Therefore, the FCC_LIM temperature detected by the FCC temperature sensor 34 is 2 to 5° C. higher than the FCC_ON temperature which is the upper limit temperature during normal cooling, and is preferably a predetermined value corresponding to weak cooling.

In addition, in the present embodiment, the condition L12 for shifting to the "simultaneous cooling mode" corresponding to the overload condition is limited by the rotation speed of the compressor 19, but it is also possible to detect when the power is turned on at high outside air temperature, or frequent door opening and closing, etc. , to move to "simultaneous cooling mode". It is not necessary to increase the speed of compressor 19, but it is only necessary to confirm that refrigerator 11 is in an overload condition, and it is possible to shift to the "simultaneous cooling mode" earlier. In addition, at this time, condition L13 may be changed so that the simultaneous cooling mode may be canceled by detecting that the temperatures of refrigerator compartment 17 and freezer compartment 18 have dropped to some extent. Thereby, similarly to the present embodiment, the most efficient PC cooling mode can be used for a longer period of time.

Next, defrosting when the evaporator 20 is frosted in the "simultaneous cooling mode" will be described.

In the "simultaneous cooling mode", when the temperature detected by the FCC temperature sensor 34 is lower than the FCC_LIM temperature, the opening degree of the freezer compartment damper 31 is reduced. This is to give priority to the cooling of refrigerator compartment 17 when freezer compartment 18 reaches the weak cooling level, and to suppress the amount of air distribution to freezer compartment 18 . Then, when the temperature detected by the PCC temperature sensor 35 exceeds the PCC_OFF temperature after a predetermined time Tx6 has elapsed from the start of the "simultaneous cooling mode" (that is, condition L15 is satisfied), the mode shifts to the defrosting mode.

When the evaporator 20 is frosted in the "simultaneous cooling mode" and the refrigerator compartment 17 tends to be cooled slowly, the normal defrosting performed every predetermined time Tx2 is accelerated, and the defrosting interval of the evaporator 20 can be shortened. The cooling capacity of the refrigerator compartment 17 is recovered. In the "simultaneous cooling mode", the evaporator fan 30 is rotated at a high speed to ensure the air volume sent in parallel to both the refrigerator compartment 17 and the freezer compartment 18. However, when a large amount of frosting occurs on the evaporator 20, a sufficient air volume cannot be secured. At this time, compared with the freezer compartment 18 formed in front of the evaporator 20, the air volume of the refrigerator compartment 17 whose air is blown from the evaporator 20 is long is greatly reduced. Therefore, in order to give priority to the cooling of refrigerating room 17 when freezing room 18 has reached the weak cooling level, to suppress the air volume distribution to freezing room 18, and at the time when it is determined that cooling of refrigerating room 17 is insufficient after a predetermined time Tx6 has elapsed, By shortening the defrosting interval of evaporator 20, the cooling capacity of refrigerator compartment 17 can be restored earlier.

As described above, the refrigerator of the present invention also has a "simultaneous cooling mode" only under overload conditions in addition to the "FC cooling mode" and the "PC cooling mode", in which, on the downstream side of the main condenser 21, via the flow The road switching valve 40 is connected in parallel with the first anti-dew pipe 44 and the second anti-dew pipe 41, and is arbitrarily selected. Thus, during normal operation, the first anti-dew pipe 44 and the second anti-dew pipe 41 can be alternately switched and used, which can suppress the heat load caused by the first anti-dew pipe 44, and simultaneously use the first anti-dew pipe in parallel during overload operation. The dew pipe 44 and the second anti-dew pipe 41 can reduce the amount of refrigerant circulation and suppress pressure loss.

In addition, in the refrigerator of the present embodiment, the operation of completely closing the flow path switching valve 40 is not performed, but if the flow path switching valve 40 is completely closed in the "stop mode", the liquid refrigerant in the main condenser 21 will not flow to the main condenser 21. If the downstream side flows, the amount of high-temperature liquid refrigerant flowing into the evaporator 20 in the "stop mode" can be suppressed, and the heat load of the refrigerator can be reduced.

As described above, the present invention includes at least a refrigeration cycle including a compressor, an evaporator, and a condenser having a main condenser of a forced air cooling system, a flow switching valve connected to the downstream side of the main condenser, and a The sub-condenser on the downstream side of the flow path switching valve includes a plurality of anti-dew pipes connected in parallel in its structure. When the refrigeration cycle operates under normal conditions, the refrigerant flows alternately through the plurality of anti-dew tubes, and when it operates under overload conditions, the refrigerant flows through the plurality of anti-dew tubes in parallel.

Thereby, it is possible to suppress the heat load caused by the anti-dew pipes in normal times, and to suppress pressure loss caused by the anti-dew pipes by using a plurality of anti-dew pipes in parallel at the time of overload with a large refrigerant circulation amount. The time of overload means, for example, when the door is frequently opened and closed in summer when the outside air temperature and humidity are high, or when food with a high temperature is stored. At this time, the operation rate of the refrigeration cycle increases, the refrigerant circulation amount increases, and it is necessary to prevent dew condensation around the refrigerator casing in which the dew prevention pipe is arranged. At this time, by using the anti-dew pipes in parallel to reduce the circulation amount of the refrigerant per one, the pressure loss caused by the anti-dew pipes can be suppressed.

In addition, the present invention includes a refrigerating room and a freezing room, and the condition that both the refrigerating room and the freezing room are higher than a predetermined temperature is regarded as an overload condition, and the refrigerant is made to flow through a plurality of anti-dew tubes in parallel.

Accordingly, the operation under normal conditions and the operation under overload conditions are performed separately, and energy saving can be achieved by operating in accordance with each condition. In addition, on the basis of reliably grasping the overload time with a large amount of refrigerant circulation, it is also possible to use a plurality of anti-dew pipes in parallel at the same time to suppress the pressure loss caused by the anti-dew pipes, and to suppress the temperature rise of the refrigerator compartment and the freezer compartment. .

In addition, the present invention includes a refrigerator compartment, a freezer compartment, a refrigeration cycle, an evaporator as a component of the refrigeration cycle, an evaporator fan that supplies cold air generated by the evaporator to the refrigerator compartment and the freezer compartment, and an evaporator fan that cuts off the supply from the evaporator to the refrigerator compartment. The refrigerating compartment damper of cold air, and the freezer compartment damper of blocking the cold air supplied from the evaporator to the freezing compartment. It also has an FCC temperature sensor that detects the temperature of the freezer compartment, and a PCC temperature sensor that detects the temperature of the refrigerator compartment. And, there are: FC cooling mode, which opens the freezer door, closes the refrigerator door, operates the refrigeration cycle and supplies cold air generated by the evaporator, thereby cooling the freezer; and PC cooling mode, closes the freezer door, and opens the refrigerator door , to operate the refrigeration cycle and supply cold air generated by the evaporator to cool the refrigerator compartment.

Furthermore, there are: simultaneous cooling mode, which opens the freezer door, opens the refrigerator door, operates the refrigeration cycle and supplies cool air generated by the evaporator, thereby simultaneously cooling the freezer and the refrigerator; and stops the cycle cooling mode, closes the freezer door , open the air door of the refrigerating room, stop the refrigeration cycle and run the evaporator fan, thereby exchanging heat between the evaporator and the air in the refrigerating room. Cooling is performed by combining the FC cooling mode, the PC cooling mode, and the off-cycle cooling mode under normal conditions, and cooling is performed by combining the simultaneous cooling mode and the FC cooling mode under overload conditions.

Therefore, under normal conditions, the PC cooling mode with high efficiency is maintained as much as possible, and the cooling of the freezer is continued under overload conditions, and the cooling capacity of the freezer and refrigerator can be automatically and appropriately adjusted, and the cooling of the refrigerator and freezer can be suppressed. The temperature of the chamber rises.

In addition, in the present invention, the compressor is a variable-speed compressor. During normal operation, the compressor is operated at a speed lower than a predetermined speed, and the FC cooling mode, the PC cooling mode, and the cycle-stop cooling mode are combined for cooling. Cooling is performed by operating the compressor at a predetermined speed or higher and combining the simultaneous cooling mode and the FC cooling mode.

Thereby, the temperature rise of the evaporator in simultaneous cooling mode can be suppressed, and it can suppress that the cooling capacity of a freezer compartment is insufficient.

In addition, the present invention includes an upper machine room and a lower machine room, a compressor is arranged in the upper machine room, and a flow path switching valve is arranged in the lower machine room.

Thereby, the noise of a refrigerator can be reduced by suppressing the resonance of the connection piping of a flow path switching valve, and a compressor.

Industrial Utilization Possibility

As described above, in the refrigerator according to the present invention, by connecting a plurality of anti-dew pipes in parallel via the flow path switching valve on the downstream side of the main condenser, it is possible to arbitrarily adjust the anti-dew pipe according to the installation environment and operating state of the refrigerator. Because of the pressure loss and heat load caused, it can also be applied to other refrigeration applications such as commercial refrigerators.

Description of reference symbols

11 cold storage

12 Shell

15 Lower Mechanical Room

16 Upper Mechanical Room

19 compressor

20 evaporator

24 evaporator

30 evaporator fan

31 Freezer door

32 Refrigerator door

33 pipes

34 FCC temperature sensor

35 PCC temperature sensor

36 DEF temperature sensor

37 anti-dew tube

38 Dryer

39 Throttle

40 flow switching valve

41 The second anti-dew pipe (secondary condenser)

42 Confluence

43 Vacuum insulation materials

44 The first anti-dew pipe (secondary condenser)

50 evaporator fan

51 Freezer door

52 Refrigerator door

53 pipeline

54 FCC temperature sensor

55 PCC temperature sensor

56 compressor

57 evaporator

58 DEF temperature sensor

Claims (5)

1. a freezer, is characterized in that:

Comprise the kind of refrigeration cycle at least with compressor, evaporimeter, condenser,

Described condenser have force cooling air mode main condenser, be connected in described main condenser downstream flow channel switching valve and be connected in the secondary condenser in the downstream of described flow channel switching valve, described secondary condenser comprises a plurality of dew eliminating tubes of connection arranged side by side in structure

Described kind of refrigeration cycle, when turning round with usual conditions, makes cold-producing medium alternating current cross a plurality of described dew eliminating tubes, and when turning round with overload condition, makes cold-producing medium parallel flow cross a plurality of described dew eliminating tubes.

2. freezer as claimed in claim 1, is characterized in that:

Comprise refrigerating chamber and refrigerating chamber, using described refrigerating chamber and described refrigerating chamber all higher than the situation of set point of temperature as overload condition, make cold-producing medium parallel flow cross a plurality of described dew eliminating tubes.

3. freezer as claimed in claim 1, is characterized in that:

The FCC temperature sensor of the temperature that comprise refrigerating chamber, refrigerating chamber, described kind of refrigeration cycle, evaporator fan, the refrigerating chamber air door that blocks the cold air of supplying with to described refrigerating chamber from described evaporimeter, the refrigerating chamber air door that blocks the cold air of supplying with to described refrigerating chamber from described evaporimeter that the cold air being produced by described evaporimeter is supplied with to described refrigerating chamber and described refrigerating chamber, detects described refrigerating chamber and detect the PCC temperature sensor of the temperature of described refrigerating chamber

Described freezer has following pattern:

FC refrigerating mode, opens described refrigerating chamber air door, closes described refrigerating chamber air door, and described kind of refrigeration cycle is turned round and supply with the cold air being produced by described evaporimeter, thus cooling described refrigerating chamber;

PC refrigerating mode, closes described refrigerating chamber air door, opens described refrigerating chamber air door, and described kind of refrigeration cycle is turned round and supply with the cold air being produced by described evaporimeter, thus cooling described refrigerating chamber;

Refrigerating mode, opens described refrigerating chamber air door simultaneously, opens described refrigerating chamber air door, and described kind of refrigeration cycle is turned round and supply with the cold air being produced by described evaporimeter, thus cooling described refrigerating chamber of while and refrigerating chamber; With

Stop circulating cooling pattern, close described refrigerating chamber air door, open described refrigerating chamber air door, stop described kind of refrigeration cycle and the described evaporator fan that turns round, make thus the air in described evaporimeter and described refrigerating chamber carry out heat exchange,

Under usual conditions, combine FC refrigerating mode and PC refrigerating mode, stop circulating cooling pattern carry out cooling, and under overload condition combination simultaneously refrigerating mode and FC refrigerating mode carry out cooling.

4. freezer as claimed in claim 3, is characterized in that:

Described compressor is speed changeable compressor, when common running, make described compressor with lower than regulation rotation speed operation and combine FC refrigerating mode and PC refrigerating mode, stop circulating cooling pattern and carry out coolingly, and under overload condition, make described compressor more than regulation rotating speed turn round and to combine while refrigerating mode and FC refrigerating mode carries out cooling.

5. the freezer as described in any one in claim 1 or 2, is characterized in that:

Comprise Machine Room, top and Machine Room, bottom, in Machine Room, described top, configure described compressor, and configure described flow channel switching valve in Machine Room, described bottom.