WO2012157263A1

WO2012157263A1 - Refrigerator

Info

Publication number: WO2012157263A1
Application number: PCT/JP2012/003181
Authority: WO
Inventors: 境　寿和; 西村　晃一
Original assignee: パナソニック株式会社
Priority date: 2011-05-18
Filing date: 2012-05-16
Publication date: 2012-11-22
Also published as: CN103547872A; EP2711654A4; CN103547872B; EP2711654A1

Abstract

A refrigeration cycle comprising at least a compressor (19), an evaporator (20) and a condenser is provided inside a casing. The condenser comprises a forced-air-cooling main condenser (21), a flow passage switching valve (3) connected to the downstream side of the main condenser (21), and an auxiliary condenser connected to the downstream side of the flow passage switching valve (3). The auxiliary condenser comprises a plurality of anti-condensation pipes (1, 2) connected in parallel, and refrigerant flows in parallel to the plurality of anti-condensation pipes (1, 2) when the refrigeration cycle is operated under high load conditions.

Description

refrigerator

The present invention relates to a refrigerator that has a condenser pipe (hereinafter referred to as “dew-proof pipe”) that prevents condensation on the wall surface and that suppresses pressure loss caused by the dew-proof pipe.

In addition, the present invention has dampers that block cold air in the freezing room and the refrigerating room, respectively, and uses a single evaporator to individually cool the freezing room and the refrigerating room, thereby improving the efficiency of the refrigerating cycle. It relates to the refrigerator.

Also, the present invention relates to a refrigerator, and more particularly, to a control that suppresses temperature rise in a refrigerator during defrosting by a heater in a refrigerator that cools a storage room by latent heat and sensible heat of frost attached to a cooler.

From the standpoint of energy saving, in home refrigerators, in addition to a condenser that is air-cooled by a fan, a dew-proof pipe that is attached to the inside of the outer casing and prevents condensation on the wall surface is used in combination. In this case, the refrigerator for home uses a flammable refrigerant from the viewpoint of preventing global warming, and a dew-proof pipe having a small pipe inner diameter is used for the purpose of reducing the amount of the enclosed refrigerant.

Therefore, in order to suppress the pressure loss caused by the dew proof pipe, a refrigerator that changes the configuration of the dew proof pipe as necessary has been proposed (for example, see Patent Document 1).

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

FIG. 21 is a configuration diagram of a refrigeration cycle of a conventional refrigerator.

21, this refrigeration cycle includes a compressor 60, a main condenser 61, a dew-proof pipe 62 for a freezer compartment, a dew-proof pipe 63 for a refrigerator compartment, and a flow path switching valve 64. Further, this refrigeration cycle includes a refrigeration throttle 65, a refrigeration room evaporator 66, a refrigeration room fan 67, a refrigeration throttle 68, a freezing room evaporator 69, and a freezing room fan 70.

Here, the conventional refrigerator cools the refrigerator compartment (not shown) using the refrigerator compartment evaporator 66 and cools the refrigerator compartment (not shown) using the freezer evaporator 69. The dew-proof pipe 63 for the refrigerating room is installed at the opening of the refrigerating room (not shown) to prevent condensation on the wall surface, and the dew-proof pipe 62 for the freezer room is provided in the freezer room (not shown). It is installed in the opening to prevent condensation on the wall surface.

The operation of the conventional refrigerator configured as described above will be described below.

The refrigerant discharged from the compressor 60 is radiated and liquefied by the main condenser 61 and the dew-proofing pipe 62 for the freezer, and then supplied to the flow path switching valve 64. When the refrigerator compartment (not shown) needs to be cooled, the flow path switching valve 64 is switched to dissipate heat through the refrigerator compartment dew-proof pipe 63, and then the pressure is reduced by the refrigerator refrigerator 65 to the refrigerator compartment evaporator 66. Supply refrigerant and evaporate. At this time, the refrigerator compartment (not shown) is cooled by driving the refrigerator compartment fan 67.

On the other hand, when the freezing room (not shown) needs to be cooled, the flow path switching valve 64 is switched, the pressure is reduced by the freezing restrictor 68, and the refrigerant is supplied to the freezing room evaporator 69 for evaporation. At this time, the freezer compartment fan 70 is driven to cool the freezer compartment (not shown).

As a result, when the freezer compartment (not shown) is cooled, it can be operated without flowing the refrigerant through the refrigerating room dew-proof pipe 63, and the pressure loss caused by the refrigerating room dew-proof pipe 63 is reduced. Can be suppressed. Further, it is possible to prevent a part of the heat radiated by flowing a refrigerant through the dew-proof pipe 63 for the refrigerating room from entering the refrigerating room (not shown) and becoming a heat load.

However, in the conventional refrigerator configuration, when the refrigerator compartment is cooled, it is necessary to flow the refrigerant in series through the freezer compartment dew pipe 62 and the refrigerator compartment dew pipe 63, and the pressure loss of the dew pipe is reduced. This causes an increase in power consumption.

Moreover, in the conventional refrigerator configuration, it is not possible to suppress the pressure loss and the heat load caused by the freezing room dew-proof pipe 62 regardless of the installation environment and operating state of the refrigerator.

Therefore, it has been a problem to suppress the pressure loss and heat load caused by the dew-proof pipe according to the installation environment and operating state of the refrigerator.

The present invention solves the conventional problem, and by connecting a plurality of dew-proof pipes in parallel via a flow path switching valve on the downstream side of the main condenser, it can be prevented according to the installation environment and operating state of the refrigerator. The purpose is to regulate and control the pressure loss and heat load caused by the dew pipe.

Also, in conventional refrigerators for home use, there are refrigerators in which the efficiency of the refrigeration cycle is improved by cooling each of the freezer compartment and the refrigerator compartment using one evaporator from the viewpoint of energy saving. This enhances the efficiency of the refrigeration cycle by cooling the refrigerator compartment having a relatively high air temperature at an evaporation temperature higher than that of the freezer compartment.

Furthermore, it has been proposed to defrost the evaporator by using the amount of heat of food in the refrigerator compartment while the compressor is stopped, using dampers that block cold air provided in the freezer compartment and the refrigerator compartment respectively ( For example, see Patent Document 2). This is intended to save energy by reducing the capacity of the refrigeration cycle necessary for cooling the refrigerator compartment while reducing the electric power of the heating heater when removing frost attached to the evaporator.

FIG. 22 is a longitudinal sectional view of a conventional refrigerator, FIG. 23 is a configuration diagram of a refrigeration cycle of a conventional refrigerator, FIG. 23 is a waveform diagram of the temperature behavior of the conventional refrigerator temperature sensor and the refrigerator compartment, and FIG. It is a flowchart which shows the control at the time of defrosting.

22 and FIG. 23, the refrigerator 11 includes a housing 12, a door 13, legs 14 that support the housing 12, a lower machine room 15 provided in a lower portion of the housing 12, and a refrigeration disposed in an upper portion of the housing 12. It has the freezer compartment 18 arrange | positioned at the chamber 17 and the lower part of the housing | casing 12. FIG. In addition, as components constituting the refrigeration cycle, a compressor 56 housed in the lower machine chamber 15, an evaporator 20 housed on the back side of the freezer room 18, and a main condenser 21 housed in the lower machine room 15 are provided. Have. The refrigerator 11 includes a partition wall 22 that partitions the lower machine room 15, a condenser fan 23 that is attached to the partition wall 22 to air-cool the main condenser 21, an evaporating dish 57 that is installed above the compressor 56, and the lower machine room 15. A bottom plate 25 is provided. The refrigerator 11 includes a plurality of air inlets 26 provided on the bottom plate 25, an outlet 27 provided on the back side of the lower machine room 15, and a connection connecting the outlet 27 of the lower machine room 15 and the upper part of the housing 12. A ventilation path 28 is provided. Here, the lower machine chamber 15 is divided into two chambers by the partition wall 22, and the main condenser 21 is housed on the windward side of the condenser fan 23, and the compressor 56 and the evaporating dish 57 are housed on the leeward side.

In addition, the refrigerator 11 is located on the downstream side of the main condenser 21 as components constituting the refrigeration cycle, and includes a dew-proof pipe 37 that is thermally coupled to the outer surface of the housing 12 around the opening of the freezer compartment 18. It is located downstream of the dew pipe 37 and has a dryer 38 for drying the circulating refrigerant, a throttle 38 for connecting the dryer 38 and the evaporator 20 and depressurizing the circulating refrigerant. In addition, the refrigerator 11 supplies the cooler air generated in the evaporator 20 to the refrigerator compartment 17 and the freezer compartment 18, the evaporator fan 50 that supplies the refrigerator compartment 18, and the refrigerator compartment damper 51 that shuts off the cold air supplied to the refrigerator compartment 18 and the refrigerator compartment 17. A cold room damper 52 for shutting off the cold air, a duct 53 for supplying cold air to the cold room 17, an FCC temperature sensor 54 for detecting the temperature of the freezer room 18, and a PCC temperature sensor 55 for detecting the temperature of the freezer room 17. ing.

When the temperature detected by the PCC temperature sensor 55 rises to a predetermined ON temperature, the freezer damper 51 is closed while the compressor 56 is stopped, the refrigerator compartment damper 52 is opened, and the evaporator fan 50 is driven. Thereby, the refrigerator compartment 17 is cooled using the evaporator 20 and the low-temperature sensible heat of the frost adhering to the evaporator 20 and the latent heat of fusion of the frost (hereinafter, this operation is referred to as “off-cycle cooling”).

After a predetermined time from the start of off-cycle cooling, the freezer damper 51 is closed, the refrigerator compartment damper 52 is opened, and the compressor 56, the condenser fan 23, and the evaporator fan 50 are driven. By driving the condenser fan 23, the main condenser 21 side of the lower machine chamber 15 partitioned by the partition wall 22 becomes negative pressure, and external air is sucked from the plurality of intake ports 26, and the compressor 56 and the evaporating dish 57 side are positive pressure. Then, the air in the lower machine chamber 15 is discharged to the outside from the plurality of discharge ports 27.

On the other hand, the refrigerant discharged from the compressor 56 is condensed while leaving a part of the gas while exchanging heat with the outside air in the main condenser 21 and then supplied to the dewproof pipe 37. The refrigerant that has passed through the dew-proof pipe 37 radiates heat through the housing 12 and condenses while warming the opening of the freezer compartment 18. The liquid refrigerant that has passed through the dew-proof pipe 37 is dehydrated by the dryer 38, depressurized by the throttle 39, and is evaporated by the evaporator 20, while exchanging heat with the air in the refrigerator compartment 17 and cooling the refrigerator compartment 17. Then, it is returned to the compressor 56 as a gaseous refrigerant (hereinafter, this operation is referred to as “PC cooling”). At this time, since the temperature of the air in the refrigerator compartment 17 is higher than that of the freezer compartment 18 and the temperature of the evaporator 20 is increased by off-cycle cooling, it quickly reaches a high evaporation temperature during PC cooling. be able to.

Next, when the temperature detected by the PCC temperature sensor 55 falls to a predetermined OFF temperature or when the temperature detected by the FCC temperature sensor 54 rises to a predetermined ON temperature, the freezer damper 51 is opened and refrigerated. The chamber damper 52 is closed, and the compressor 56, the condenser fan 23, and the evaporator fan 50 are driven. Thereafter, by operating the refrigeration cycle in the same manner as PC cooling, the freezer compartment 18 is cooled by exchanging heat between the inside air of the freezer compartment 18 and the evaporator 20 (hereinafter, this operation is referred to as “FC cooling”).

24, section e corresponds to off-cycle cooling, section f corresponds to PC cooling, section g corresponds to FC cooling, and section h corresponds to cooling stop operation. The compressor 56 is driven between the section f and the section g, and is stopped between the section h and the section e. Moreover, the freezer compartment 18 is cooled during the section g, and the refrigerator compartment 17 is cooled between the section e and the section f. Here, the reason why the temperature change in the upper part of the refrigerating chamber 17 is large is that the upper part is adjacent to the high temperature outside air, while the lower part is adjacent to the low temperature freezing room 18, so during the non-cooling period. This is because the temperature difference between the upper and lower sides becomes larger and the air volume at the upper part is increased during cooling to quickly cool the upper part at a high temperature.

Next, when the temperature detected by the FCC temperature sensor 54 falls to a predetermined OFF temperature, the freezer damper 51 and the refrigerator compartment damper 52 are closed, and the compressor 56, the condenser fan 23, and the evaporator fan 50 are stopped. (Hereafter, this operation is referred to as “cooling stop”). During normal operation, a series of operations of off-cycle cooling, PC cooling, FC cooling, and cooling stop are repeated in order. Then, after the normal operation is continued for a predetermined time, in order to remove frost attached to the evaporator 20, off-cycle cooling is performed for a relatively long time (hereinafter, this operation is referred to as “off-cycle differential”).

FIG. 25 is a flowchart showing control of off-cycle differential from “defrost start” to “defrost end determination”. As shown in FIG. 25, first, when the normal operation has exceeded a predetermined time immediately before starting the PC cooling, it is determined that “defrosting start”, that is, the start of off-cycle differential. This is aimed at the timing when the temperature in the refrigerator compartment 17 is relatively high and the amount of heat is large in order to melt and remove the frost attached to the evaporator 20 using the amount of heat in the refrigerator compartment 17. Then, with the compressor 56 stopped, the freezer damper 51 is closed, the refrigerating room damper 52 is opened, and the evaporator fan 50 is driven. Implement frost.

And, when a DEF temperature sensor (not shown) for detecting the temperature of the evaporator 20 detects that the temperature exceeds 0 ° C., “defrosting completion determination”, that is, frost attached to the evaporator 20 has been completely removed. Determine, end the off-cycle differential operation, and return to normal operation.

By this off-cycle differential, it is possible to reduce the power of the heating heater that is normally used when the evaporator 20 is defrosted, and at the same time save energy by reducing the capacity of the refrigeration cycle necessary for cooling the refrigerator compartment 17. Can be achieved.

In addition, by this series of operations, the temperature of the evaporator 20 during PC cooling is kept higher than that during FC cooling, so that the efficiency of the refrigeration cycle can be increased and frost adhering to the evaporator 20 by off-cycle cooling. By reusing the latent heat of melting, energy can be saved by reducing the capacity of the refrigeration cycle necessary for cooling the refrigerator compartment 17 while reducing heater power (not shown) during defrosting.

However, the conventional refrigerator configuration has a problem that the time required for off-cycle differential changes greatly depending on the amount of food stored in the refrigerator compartment 17. This is because the amount of heat for melting the frost adhering to the evaporator 20 depends on the amount of heat of the food stored in the refrigerator compartment 17. There is also concern that the frost will not melt completely and the off-cycle differential will not end.

Moreover, in the structure of the conventional refrigerator, the frost adhering to the evaporator 20 can be melt | dissolved reliably by adding a heater for heating and using it as an auxiliary heat source, but the heating used auxiliary It is difficult to properly adjust the output of the heater. This is because, based on the amount of food stored in the refrigerator compartment 17, the amount of heat of the off-cycle differential supplied to the evaporator 20 is unknown, and the evaporator 20 in which the attached frost is melting has almost no temperature change. This is because it is difficult to accurately determine the defrosting speed. As a result, even if a heater for heating is added and used as an auxiliary heat source, it may be used urgently when the time required for off-cycle differential is abnormally long, or it may supply more output than necessary from the beginning. high.

The present invention solves the conventional problem by determining in advance the amount of heat of the off-cycle differential supplied to the evaporator 20 and appropriately adjusting the output of the auxiliary heating heater. The purpose is to properly control the time required for off-cycle differential.

In the conventional refrigerator configuration, the PC cooling time is reduced by off-cycle cooling, and as a result, there is a problem that high refrigeration cycle efficiency cannot be obtained during PC cooling. This is because the circulating refrigerant is in a transitional state at the start of the refrigeration cycle, and the refrigeration capacity corresponding to the evaporation temperature cannot be fully exhibited.

In addition, when off-cycle cooling and PC cooling are continuously performed in order to increase the temperature of the evaporator 20, it is difficult to ensure the PC cooling time by appropriately limiting the off-cycle cooling time. This is because the cooling rate of off-cycle cooling varies greatly depending on the frosting state and temperature of the evaporator 20 and also differs from the cooling rate of PC cooling, so there is a time delay with respect to the temperature change of the air in the refrigerator compartment 17. This is because the PCC temperature sensor 55 cannot be used to accurately control the ratio between off-cycle cooling and PC cooling.

Further, in the conventional refrigerator configuration, there arises a problem that the temperature change of the refrigerator compartment 17, particularly the temperature change of the upper part becomes large. This is because when the refrigerator compartment 17 is cooled alone, the air temperature in the vicinity of the outlet of the refrigerator compartment 17 is drastically lowered and the refrigerator compartment 17 is cooled as compared to cooling the refrigerator compartment 17 and the refrigerator compartment 18 simultaneously. This is because the non-cooling time is not increased. In order to solve this problem, it is necessary to further reduce the time of off-cycle cooling and PC cooling, and to frequently repeat cooling and non-cooling of the refrigerator compartment 17, resulting in high refrigeration cycle efficiency during PC cooling. The problem that it cannot be obtained occurs.

This invention solves the conventional subject, and aims at suppressing the temperature change of a refrigerator compartment while ensuring the operating time of PC cooling appropriately.

Therefore, the operation of the conventional refrigerator disclosed in FIGS. 22 and 23 will be described below.

In FIG. 26, arrows M1 to M11 indicate mode switching in the conventional refrigerator cooling control.

In a cooling stop state in which all of the condenser fan 23, the compressor 56, and the evaporator fan 50 are stopped (hereinafter, this operation is referred to as “OFF mode”), the temperature detected by the FCC temperature sensor 54 is a predetermined value of FCC_ON temperature. Or when the temperature detected by the PCC temperature sensor 55 rises to a predetermined PCC_ON temperature (that is, the condition of the arrow M1 is satisfied), the freezer damper 51 is closed and the refrigerator compartment damper 52 is The compressor 56, the condenser fan 23, and the evaporator fan 50 are driven to open (hereinafter, this operation is referred to as “PC cooling mode”).

In the PC cooling mode, when the condenser fan 23 is driven, the main condenser 21 side of the lower machine chamber 15 partitioned by the partition wall 22 becomes negative pressure, and external air is sucked from the plurality of intake ports 26, The evaporating dish 57 side becomes positive pressure, and the air in the lower machine chamber 15 is discharged to the outside from the plurality of discharge ports 27.

On the other hand, the refrigerant discharged from the compressor 56 is condensed while leaving a part of the gas while exchanging heat with the outside air in the main condenser 21 and then supplied to the dewproof pipe 37. The refrigerant that has passed through the dew-proof pipe 37 radiates heat through the housing 12 and condenses while warming the opening of the freezer compartment 18. The liquid refrigerant that has passed through the dew-proof pipe 37 is dehydrated by the dryer 38, depressurized by the throttle 39, and is evaporated by the evaporator 20, while exchanging heat with the air in the refrigerator compartment 17 and cooling the refrigerator compartment 17. Then, it returns to the compressor 56 as a gaseous refrigerant.

During the PC cooling mode, the temperature detected by the FCC temperature sensor 54 decreases to a predetermined FCC_OFF temperature, and the temperature detected by the PCC temperature sensor 55 decreases to a predetermined PCC_OFF temperature (that is, the condition of the arrow M2). If the condition is satisfied, the transition is made to the OFF mode.

Further, during the PC cooling mode, the temperature detected by the FCC temperature sensor 54 is higher than a predetermined FCC_OFF temperature, and the temperature detected by the PCC temperature sensor 55 is lowered to the predetermined PCC_OFF temperature (ie, the arrow). When the condition of M5 is satisfied), the freezer damper 51 is opened, the refrigerator compartment damper 52 is closed, and the compressor 56, the condenser fan 23, and the evaporator fan 50 are driven. Thereafter, by operating the refrigeration cycle in the same manner as PC cooling, the freezer compartment 18 is heat-exchanged with the inside air of the freezer compartment 18 and the evaporator 20 to cool the freezer compartment 18 (this operation is hereinafter referred to as “FC cooling mode”). .

During the FC cooling mode, the temperature detected by the FCC temperature sensor 54 falls to a predetermined FCC_OFF temperature, and the temperature detected by the PCC temperature sensor 55 is equal to or higher than the predetermined PCC_ON temperature (that is, the condition of the arrow M6 is changed). If satisfied, the PC cooling mode is entered.

Further, during the FC cooling mode, the temperature detected by the FCC temperature sensor 54 falls to a predetermined FCC_OFF temperature, and the temperature detected by the PCC temperature sensor 55 indicates a temperature lower than the predetermined PCC_ON temperature (that is, an arrow). When the condition of M4 is satisfied), the mode transits to the OFF mode.

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

The defrosting heater (not shown) installed 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 operation is referred to as “defrost mode”), the frost adhering to the evaporator 20 is melted and removed, and the refrigerator compartment 17 is cooled using the sublimation heat or heat of fusion of the frost being removed.

Further, without supplying power to a defrost heater (not shown) installed in the vicinity of the evaporator 20, 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 opened. (Hereinafter, this operation is referred to as “off-cycle cooling mode”), and the refrigerator 20 uses the low-temperature sensible heat of the frost and the sublimation heat or melting heat of the frost adhering to the evaporator 20. 17 is cooled. At this time, the frost attached to the evaporator 20 is not completely thawed and removed, but by reusing the frost attached to the evaporator 20, the power of the heater (not shown) in the defrost mode is reduced. However, the refrigerator compartment 17 can be cooled.

In order to cool the freezer compartment 18 to a temperature lower than usual when the predetermined time Tx2 elapses (ie, the condition of the arrow M7 is satisfied) when the power is turned on or when the previous defrost ends during the FC cooling mode. FC cooling is continued for a predetermined time (hereinafter, this operation is referred to as “precool mode”). Next, when the predetermined time Tx3 has elapsed from the start of the precool (that is, the condition of the arrow M8 is satisfied), the operation shifts to the defrost operation. During defrosting, the temperature detected by a DEF temperature sensor (not shown) attached to the evaporator 20 is higher than a predetermined DEF_OFF temperature, or a predetermined time Tx4 elapses from the start of defrosting (ie, When the condition of the arrow M9 is satisfied), a transition to the off-cycle cooling mode is made.

Also, during the OFF mode, when a predetermined time Tm elapses from the start of OFF (that is, the condition of the arrow M10 is satisfied), the state transits to the off-cycle cooling mode.

When the predetermined time Td has elapsed from the start of off-cycle cooling during the off-cycle cooling mode (that is, the condition of the arrow M11 is satisfied), the mode transits to the OFF mode.

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

In the conventional refrigerator, since cooling control is performed by switching between PC cooling for cooling the refrigerator compartment 17 alone and FC cooling for cooling the freezer compartment 18 alone, high-temperature foods or the like are stored in the refrigerator compartment 17 or the refrigerator compartment 18. When an excessive load that is thrown in is generated, there is a concern that either the refrigerator compartment 17 or the freezer compartment 18 is not cooled for a long time.

Therefore, as indicated by the condition indicated by the arrow M5, when the temperature detected by the FCC temperature sensor 54 exceeds the predetermined FCC_ON temperature during the PC cooling, or as indicated by the condition indicated by the arrow M6. When the temperature detected by the PCC temperature sensor 55 exceeds a predetermined PCC_ON temperature during cooling, the temperature detected by the PCC temperature sensor 55 reaches the predetermined PCC_OFF temperature or detected by the FCC temperature sensor 54. Until the temperature reaches the FCC_OFF temperature of 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 “alternative cooling”). As a result, it is possible to avoid a state in which one of the refrigerator compartment 17 and the freezer compartment 18 is not cooled for a long time.

By the operation described above, the temperature of the evaporator 20 in the PC cooling mode is kept higher than that in the FC cooling mode, so that the efficiency of the refrigeration cycle can be increased and the evaporator 20 is attached to the evaporator 20 by the off-cycle cooling mode. By reusing the thawing latent heat of frost, energy saving can be achieved by reducing the capacity of the refrigeration cycle necessary for cooling the refrigerator compartment 17 while reducing heater power (not shown) during defrosting. it can.

However, in the configuration of the conventional refrigerator, when alternating cooling is performed under some overload conditions, there is a problem that either one of the refrigerator compartment 17 or the freezer compartment 18 is slowly cooled. This is because it is difficult to properly control various overload conditions such as when the power is turned on or when the doors are frequently opened and closed during the summer, with the cooling times Txr and Txf set in advance under specific overload conditions. It is because it becomes. As a result, under some overload conditions, the load balance between the refrigerator compartment 17 and the freezer compartment 18 does not match the ratio of the cooling times Txr and Txf, and either the refrigerator compartment 17 or the freezer compartment 18 is undercooled. Because. Further, if the cooling time Txr in the PC cooling mode in which the freezing chamber 18 is not cooled is not properly adjusted in the alternate cooling, there is a concern that the frozen food such as ice cream may melt under some overload conditions. .

The present invention solves the conventional problem, and while maintaining a highly efficient PC cooling mode as much as possible, the temperature rises by appropriately adjusting the cooling amount according to the load balance of the refrigerator compartment or the freezer compartment under an overload condition. It aims at suppressing.

FIG. 27 is a longitudinal sectional view of a conventional refrigerator, and FIGS. 28 to 31 are flowcharts showing the control of the conventional refrigerator.

In FIG. 27, a refrigerator 101 having a freezer compartment 102 and a refrigerator compartment 103 constitutes a refrigeration cycle together with a compressor 104, a condenser (not shown), and a decompression means (not shown), and generates cold air. A cooler 105 is included. The refrigerator 101 also has a cooling fan 106 that sucks the air in the freezer compartment 102 and the refrigerator compartment 103 into the cooler 105 and re-airs the air to the refrigerator compartment 102 and the refrigerator compartment 103.

Further, the refrigerator 101 adjusts the communication of the cold air forcedly blown into the freezer compartment 102 by the cooling fan 106 and is forced into the refrigerator compartment 103 by the freezer damper 107 that independently cools the freezer compartment 102 and the cooling fan 106. A cold room damper 108 for independently cooling the cold room 103 by adjusting the communication of the cool air to be blown is provided. Furthermore, the refrigerator 101 has a freezer compartment sensor 109 that detects the temperature in the freezer compartment 102 and a refrigerator compartment sensor 110 that detects the temperature in the refrigerator compartment 103.

In addition, a defrost heater 111 for defrosting the frost attached to the cooler 105 is provided below the cooler 105, and a cooler sensor 112 that detects the temperature of the cooler 105 is provided in the cooler 105. I have.

Next, the operation of the refrigerator will be described with reference to FIGS.

During normal cooling of the refrigerator, in the freezer cooling mode, if the detected temperature Tfc of the freezer sensor 109 is higher than a reference temperature Tfcon in step S01, the compressor 104 is started if the compressor 104 is not moving in step S02. (Step S03), the freezer compartment damper 107 is opened, the refrigerator compartment damper 108 is closed, and the cooling fan 106 is operated to cool the freezer compartment 102 (Step S04).

Next, in step S05, when the detection temperature Tfc of the freezer compartment sensor 109 is equal to or lower than a reference temperature Tfcoff, the process proceeds to step S06 and the refrigerator compartment cooling mode is set.

If the detected temperature Tpc of the refrigerator compartment sensor 110 is higher than a certain reference temperature Tpcon in step S06, the compressor 104 is started if the compressor 104 is not moving in step S07 (step S08), and the freezer damper 107 is closed. Then, the refrigerator compartment damper 108 is opened and the cooling fan 106 is operated to cool the refrigerator compartment 103 (step S09).

Next, in step S10, when the detected temperature Tpc of the refrigerator compartment sensor 110 is equal to or lower than a reference temperature Tpcoff, it is determined whether or not the cooling operation is continued in step S11. In step S11, if the temperature Tfc detected by the freezer sensor 109 is higher than a certain reference value Tfcon, the process returns to step S02 to enter the freezer cooling mode, and if it is equal to or lower than Tfcon, the process proceeds to step S12 to enter the off-cycle cooling mode. .

In step S12, the compressor 104 is first stopped. Next, in step S13, when the operation time tcomp of the compressor 104 is shorter than a certain reference value tdefrost, the process proceeds to step S14, and the detection temperature Tpc of the refrigerator compartment sensor 110 is set. When the value is higher than a certain reference value Tpcoff2, the freezer damper 107 is closed, the refrigerating room damper 108 is opened, and the cooling fan 106 is operated to cool the refrigerating room 103. Next, when the temperature Tpc detected by the refrigerating room sensor 110 is equal to or lower than a certain reference value Tpcoff2, the freezer damper 107 is closed, the refrigerating room damper 108 is closed, the cooling fan 106 is stopped, and the off-cycle cooling is performed. The operation is stopped, and the process returns to step S1 to perform normal cooling.

In step S13, when the operation time tcomp of the compressor 104 is equal to or greater than a certain reference value tdefrost, the process proceeds to step S18 and the defrosting mode is set.

In the defrost mode, the freezer damper 107 is closed in step S18, the refrigerator compartment damper 108 is closed, the cooling fan 106 is stopped, the defrost heater 111 is energized, and the frost adhering to the cooler 105 is released. In step S19, when the temperature Tdf detected by the cooler sensor 112 becomes equal to or lower than a certain reference value Tdoff, the power supply to the defrost heater is cut off, the defrost mode is terminated, and normal cooling is performed again from step S1.

By controlling in this way, the refrigerating chamber 103 can be cooled using latent heat or sensible heat of frost adhering to the cooler 105, and the energy when defrosting in the defrost mode is reduced. A refrigerator that can reduce power consumption by shortening the defrosting time has been proposed (see, for example, Patent Document 3).

However, in the above-described conventional configuration, for example, the next defrost mode is started at the same time interval regardless of whether the time of the off cycle cooling mode is long or short after the fully opened defrost mode ends. When the time is long, the amount of frost adhering to the cooler 105 decreases.

As a result, the time for one defrost mode is shortened, but since the defrost operation is performed when the amount of frost formation is small, the number of times of the defrost mode per time is the same. There was a problem that it would end up.

In the refrigerator provided with the freezer damper 107 according to the present invention, it is possible to suppress the wasteful temperature rise of the storage room by predicting the amount of frost attached to the cooler 105 from the operating state and controlling the interval of the defrost mode. The object is to provide a refrigerator.

JP 2009-264629 A JP-A-9-236369 Japanese Patent No. 2774486

The refrigerator of the present invention is characterized in that a plurality of dew prevention pipes are connected in parallel via a flow path switching valve on the downstream side of the main condenser.

This makes it possible to suppress the pressure loss caused by the dew proof pipe by using a plurality of dew proof pipes in parallel at the same time, especially when the refrigerant circulation amount is large and at a high load. Here, when the load is high, for example, when the door is frequently opened and closed in summer when the temperature and humidity of the outside air are relatively high, or when food with high temperature is stored, in such a case, As the operating rate of the refrigeration cycle increases and the amount of refrigerant circulation increases, it is necessary to prevent condensation around the refrigerator housing in which the dew-proof pipe is provided. At this time, the pressure loss resulting from the dew-proof pipe can be suppressed by simultaneously using the dew-proof pipe in parallel to reduce the amount of refrigerant circulation per bottle.

In addition, the refrigerator of the present invention detects the amount of food stored in the refrigeration room before performing the off-cycle differential, and selects the output of the heater for auxiliary use, and then performs the off-cycle differential. It is a feature. As a result, it is possible to appropriately control the time required for off-cycle differential while suppressing the output of the heater for heating, and to suppress the temperature rise of the refrigerator compartment and freezer compartment during off-cycle differential. The energy consumption of the refrigerator can be reduced by reducing the amount of electric power of the heating heater necessary for defrosting.

The refrigerator of the present invention is installed above the PCC temperature sensor, the FCC temperature sensor for detecting the temperature of the freezer room, the PCC temperature sensor for detecting the temperature of the refrigerator compartment, and detects the temperature of the upper part of the refrigerator compartment. And a DFP temperature sensor. The refrigerator of the present invention opens the freezer damper, closes the cold room damper, closes the freezer damper while operating the freezing cycle, closes the freezer damper, and closes the cold room damper. Open the PC cooling mode to cool the refrigeration room while operating the refrigeration cycle, close the refrigeration room damper, open the refrigeration room damper, and operate the evaporator fan while stopping the refrigeration cycle. This has an off-cycle cooling mode that exchanges heat between the evaporator and the air in the refrigerator compartment, and determines whether the FC cooling mode and the PC cooling mode are ON / OFF based on the temperature detected by the FCC temperature sensor or PCC temperature sensor. In addition, ON / OFF of the off-cycle cooling mode is determined based on the temperature detected by the DFP temperature sensor.

As a result, the time for off-cycle cooling can be adjusted appropriately to ensure sufficient PC cooling time, and the temperature change in the upper part of the refrigerator compartment can be suppressed. The energy saving of the refrigerator can be achieved by obtaining.

In addition, the refrigerator of the present invention is characterized by cooling by combining the FC cooling mode, the PC cooling mode, and the off-cycle cooling mode under normal conditions, and cooling by combining the simultaneous cooling mode and the FC cooling mode under overload conditions. To do. As a result, while maintaining a highly efficient PC cooling mode under normal conditions as much as possible, and by continuously adjusting the cooling amount of the freezer compartment and the refrigerator compartment while continuing to cool the freezer compartment under overload conditions, Temperature rises in the refrigerator compartment and the freezer compartment can be suppressed.

In addition, the refrigerator of the present invention includes a first storage chamber having an opening on the front surface, a second storage chamber having an opening on the front surface, a refrigeration cycle including a cooler that generates cold air, and cooling A cooling fan that circulates the cool air generated in the container to the first storage chamber and the second storage chamber, a first damper that selectively flows the cool air from the cooling fan to the first storage chamber, and the cool air from the cooling fan And a defrost heater for removing frost attached to the cooler by heat. The refrigerator of the present invention operates the cooling fan when the refrigeration cycle is stopped, and opens the first damper or the second damper to cool the first storage chamber or the second storage chamber. In the refrigerator equipped with a cooling mode and a defrosting mode for defrosting the frost attached to the cooler with a defrosting heater, the configuration is characterized by controlling the interval from the end of the defrosting mode to the next defrosting mode. Yes.

With this configuration, in a refrigerator equipped with a freezer damper, it is possible to adjust the defrosting interval by predicting the amount of frost attached to the cooler, and to prevent wasteful temperature rise in the storage room. It becomes possible to provide a refrigerator.

FIG. 1 is a longitudinal sectional view of a refrigerator in the first embodiment of the present invention. FIG. 2 is a cycle configuration diagram of the refrigerator in the first embodiment of the present invention. FIG. 3 is a front view of the refrigerator according to the first embodiment of the present invention. FIG. 4 is a configuration diagram of the back surface of the refrigerator in the first embodiment of the present invention. FIG. 5 is a schematic diagram of the control pattern of the refrigerator in the first embodiment of the present invention. FIG. 6 is a longitudinal sectional view of the refrigerator in the second embodiment of the present invention. FIG. 7 is a cycle configuration diagram of the refrigerator in the second embodiment of the present invention. FIG. 8 is a waveform diagram of the temperature sensor behavior of the refrigerator in the second embodiment of the present invention. FIG. 9 is a flowchart showing control during defrosting of the refrigerator according to the second embodiment of the present invention. FIG. 10 is a longitudinal sectional view of a refrigerator in the third embodiment of the present invention. FIG. 11 is a cycle configuration diagram of the refrigerator in the third embodiment of the present invention. FIG. 12 is a waveform diagram of the temperature sensor behavior of the refrigerator in the third embodiment of the present invention. FIG. 13 is a longitudinal sectional view of a refrigerator in the fourth embodiment of the present invention. FIG. 14 is a cycle configuration diagram of the refrigerator in the fourth embodiment of the present invention. FIG. 15 is a diagram showing state transitions and switching conditions in the cooling control of the refrigerator in the fourth embodiment of the present invention. FIG. 16 is a longitudinal sectional view of a refrigerator in the fifth embodiment of the present invention. FIG. 17 is a diagram illustrating the relationship between the interval between the defrost modes of the refrigerator and the accumulated time in the off-cycle cooling mode according to the fifth embodiment of the present invention. FIG. 18 is a diagram showing the relationship between the interval of the defrosting mode of the refrigerator and the door integrated opening time in the fifth embodiment of the present invention. FIG. 19 is a diagram showing the relationship between the interval of the defrosting mode of the refrigerator and the outside air humidity in the fifth embodiment of the present invention. FIG. 20 is a diagram illustrating the relationship between the interval of the defrosting mode of the refrigerator and the internal temperature setting in the fifth embodiment of the present invention. FIG. 21 is a cycle configuration diagram of a conventional refrigerator. FIG. 22 is a longitudinal sectional view of a conventional refrigerator. FIG. 23 is a cycle configuration diagram of a conventional refrigerator. FIG. 24 is a waveform diagram of the temperature behavior of the temperature sensor and the upper part of the refrigerator in the conventional refrigerator. FIG. 25 is a flowchart showing control during defrosting of a conventional refrigerator. FIG. 26 is a diagram showing state transitions and switching conditions in cooling control of a conventional refrigerator. FIG. 27 is a longitudinal sectional view of a conventional refrigerator. FIG. 28 is a flowchart showing control of a conventional refrigerator. FIG. 29 is a flowchart showing control of a conventional refrigerator. FIG. 30 is a flowchart showing control of a conventional refrigerator. FIG. 31 is a flowchart showing control of a conventional refrigerator.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the same components as those in the conventional example are denoted by the same reference numerals, and detailed description thereof will be omitted. The present invention is not limited to the following embodiment.

(First embodiment)
1 is a longitudinal sectional view of a refrigerator according to the 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, and FIG. 3 is a first embodiment of the present invention. 4 is a schematic diagram of the front of the refrigerator in FIG. 4, FIG. 4 is a schematic diagram of the back of the refrigerator in the first embodiment of the present invention, and FIG. 5 is a schematic diagram of the control pattern of the refrigerator in the first embodiment of the present invention. .

In FIG. 1, the refrigerator 11 includes a housing 12, a door 13, and legs 14 that support the housing 12. The refrigerator 11 is provided in a lower machine room 15 provided in a lower portion of the housing 12 and an upper rear portion of the housing 12. An upper machine room 16, a refrigerating room 17 that is a storage room arranged at the upper part of the housing 12, and a freezer room 18 arranged at the lower part of the housing 12 are formed.

The refrigeration cycle includes a compressor 19 housed in the upper machine room 16, an evaporator 20 housed in the back side of the freezer room 18, and a main condenser having a large heat dissipation among the condensers housed in the lower machine room 15. 21.

Further, a partition wall 22 for partitioning the lower machine chamber 15, a condenser fan 23 attached to the partition wall 22 for air-cooling the main condenser 21, an evaporating dish 24 placed on the back side of the lower machine chamber 15, and a bottom plate 25 of the lower machine chamber 15. Have Here, the main condenser 21 is composed of a spiral fin tube in which a strip-shaped fin is wound around a refrigerant pipe having an inner diameter of about 4.5 mm.

The lower machine chamber 15 includes a plurality of intake ports 26 provided in the bottom plate 25, a discharge port 27 provided on the back side of the lower machine chamber 15, a discharge port 27 of the lower machine chamber 15, and the upper machine chamber 16. A connecting air passage 28 is provided. Here, the lower machine chamber 15 is divided into two chambers by a partition wall 22, and a main condenser 21 is housed on the windward side of the condenser fan 23 and an evaporating dish 24 is housed on the leeward side.

As shown in FIGS. 2 to 4, as a condenser, in addition to the main condenser 21, a first condenser disposed in the opening of the freezing chamber 18, which is a sub-condenser that dissipates high-temperature heat in the refrigeration cycle. A dew-proof pipe 1 and a second dew-proof pipe 2 disposed on the back side of the housing 12 are provided.

Further, a flow path switching valve 3 that connects the downstream side of the main condenser 21 and the first and second dew-

proof pipes

1 and 2 that are sub-condensers, the downstream side of the first dew-proof pipe 1 and the second dew-proofing. A junction 4 connecting the downstream sides of the pipe 2, a dryer 5 installed downstream of the junction 4, and a throttle 6 installed downstream of the dryer 5 are provided. Here, the first dew-proof pipe 1 and the second dew-proof pipe 2 are made of refrigerant pipes having an inner diameter of about 3.2 mm, and are thermally coupled to the outer surface of the housing 12.

The operation of the refrigerator according to the first embodiment of the present invention configured as described above will be described below.

In a high load condition, the flow path switching valve 3 is switched to open the connection to the first dew-proof pipe 1 and open the connection to the second dew-proof pipe 2, and in conjunction with the operation of the compressor 19, The condenser fan 23 is driven. When the condenser fan 23 is driven, the main condenser 21 side of the lower machine chamber 15 partitioned by the partition wall 22 has a negative pressure, and external air is sucked from the plurality of intake ports 26, and the evaporating dish 24 side has a positive pressure. The air in 15 is discharged to the outside through a plurality of discharge ports 27.

On the other hand, the refrigerant discharged from the compressor 19 is condensed while leaving a part of the gas while exchanging heat with the outside air in the main condenser 21, and is then connected to the first dew-proof pipe 1 and the first through the flow path switching valve 3. 2 Supplied to the dew proof pipe 2. At this time, the pipe of the main condenser 21 is in the initial stage where the refrigerant condenses, and there is more gaseous refrigerant than the first dew-proof pipe 1 and the second dew-proof pipe 2 and the flow rate is relatively fast. A pipe having an inner diameter larger than that of the first dew-proof pipe 1 and the second dew-proof pipe 2, preferably a pipe having an inner diameter of 4 mm or more is preferably used.

The refrigerant that has passed through the first dew-proof pipe 1 dissipates heat and condenses outside through the housing 12 while warming the opening of the freezer compartment 18, and the refrigerant that has passed through the second dew-proof pipe 2 While the back surface of the body 12 is warmed, heat is radiated to the outside through the housing 12 and condensed. The liquid refrigerant that has passed through the first dew-proof pipe 1 and the second dew-proof pipe 2 is water-removed by the dryer 5, depressurized by the throttle 6, and evaporated in the evaporator 20 while being stored in the refrigerator compartment 17 and the freezer compartment 18. After exchanging heat with air, it is returned to the compressor 19 as a gaseous refrigerant.

As described above, under a high load condition, by flowing a refrigerant in parallel to the first dew-proof pipe 1 and the second dew-proof pipe 2, the refrigerant circulation amount per one is reduced, so that the dew-proof pipe The resulting pressure loss can be suppressed.

Next, under normal conditions, the flow path switching valve 3 is switched to close the connection to the first dew prevention pipe 1 and open the connection to the second dew prevention pipe 2. At this time, the refrigerant discharged from the compressor 19 is condensed while leaving a part of the gas while exchanging heat with the outside air in the main condenser 21, and then the second refrigerant as a sub-condenser via the flow path switching valve 3. Supplied to the dewproof pipe 2. And the refrigerant | coolant which passed the 2nd dew prevention pipe 2 is thermally radiated and condensed through the housing | casing 12, heating the back surface of the housing | casing 12.

On the other hand, the first dew-proof pipe 1 in which the refrigerant does not flow from the flow path switching valve 3 does not radiate heat and eliminates the temperature difference from the surroundings. At this time, the high-pressure refrigerant flows from the junction 4 and the first dew prevention pipe 1 is almost filled with the liquid refrigerant. Thus, the liquid refrigerant does not move while staying in the piping of the first dew prevention pipe 1 that is not used on the high pressure side of the refrigeration cycle, and the total amount of refrigerant circulating in the refrigeration cycle is reduced. Therefore, when the first dew proof pipe 1 or the second dew proof pipe 2 is switched and not used, a pipe having an inner diameter smaller than that of the main condenser 21 is used in order to suppress a decrease in the amount of refrigerant circulating in the refrigeration cycle. It is desirable to use a pipe having an inner diameter of less than 4 mm.

Then, the liquid refrigerant that has passed through the second dew-proof pipe 2 is moisture-removed by the dryer 5, depressurized by the throttle 6, and exchanged heat with the air in the refrigerator compartment 17 and the freezer compartment 18 while evaporating in the evaporator 20. Then, it returns to the compressor 19 as a gaseous refrigerant.

As described above, under normal load conditions, the first dew prevention pipe 1 is not used, and the refrigerant flows through the second dew prevention pipe 2 to reduce the heat load caused by the first dew prevention pipe 1. Can do. In the present embodiment, the first dew-proof pipe 1 is not used on the assumption that the humidity of the outside air is low and it is not necessary to prevent condensation around the opening of the freezer compartment 18. If there is no need to prevent dew condensation in an open space and the humidity of the outside air is relatively high, it may be selected that the second dew prevention pipe 2 is not used and the refrigerant flows through the first dew prevention pipe 1.

In addition, the user can select and use the first dew-proof pipe 1 and the second dew-proof pipe 2 in accordance with the dew condensation condition around the casing 12, so that the selection can be more suitable for the installation environment. The heat load can be reduced more efficiently while avoiding the problem of occurrence.

Further, under the low outside air temperature condition, the condenser fan 23 is stopped and the flow path switching valve 3 is switched to open the connection to the first dew prevention pipe 1 and open the connection to the second dew prevention pipe 2. And At this time, the refrigerant discharged from the compressor 19 passes through the main condenser 21 with little heat exchange with the outside air, and then passes through the flow path switching valve 3 to the first dew-proof pipe 1 and the second dew-proof pipe. 2 is supplied.

Here, the reason for stopping the condenser fan 23 is to avoid a slow cooling state. When the condenser fan 23 is driven under a low outside air temperature condition, all the refrigerant is condensed in the main condenser 21, and the amount of the refrigerant supplied to the evaporator 20 is insufficient, so that the cooling of the freezer compartment 18 becomes dull. Is likely to occur. In particular, the main condenser 21 uses a pipe having a larger inner diameter than the first dew-proof pipe 1 and the second dew-proof pipe 2 which are sub-condensers from the viewpoint of suppressing pressure loss under high load conditions and normal load conditions. Therefore, when the liquid refrigerant stays, the refrigerant amount is likely to be insufficient.

Therefore, the condenser fan 23 is stopped, and the refrigerant is allowed to flow in parallel to the first dew-proof pipe 1 and the second dew-proof pipe 2, thereby ensuring the condensing capacity of the refrigeration cycle while suppressing pressure loss.

As described above, under the low outside air temperature condition, the condenser fan 23 is stopped, and the coolant is caused to flow in parallel through the first dew-proof pipe 1 and the second dew-proof pipe 2 so that the cooling state is insufficient due to insufficient refrigerant amount. The pressure loss caused by the dew-proof pipe can be suppressed while avoiding the above.

Next, the range of high load conditions, normal conditions, and low outside air temperature conditions that are operating conditions of the refrigeration cycle will be described.

In FIG. 5, the horizontal axis represents the ambient temperature around the refrigerator 11, the vertical axis represents the refrigerant circulation amount of the refrigeration cycle, and the range enclosed by a frame schematically represents the operating range of the refrigeration cycle. The operating ranges indicated by P, Q, and R indicate ranges of high load conditions, normal conditions, and low outside air temperature conditions, respectively.

In general, since the outside air temperature at which the slow cooling state due to insufficient refrigerant amount is likely to occur is 10 ° C. or less, the operating range R including at least the range where the outside air temperature is 10 ° C. or less is set as the range of the low outside air temperature condition. Is desirable. Further, an operating range P in which the outside air temperature is higher than the operating range R and the refrigerant circulation amount is a predetermined value or more is set as a high load condition range, the outside air temperature is higher than the operating range R, and the refrigerant circulation amount is predetermined. The operating range Q less than the value is set as the normal condition range.

Note that when R600a is used as the refrigerant, the pressure loss of the first dew-proof pipe 1 and the second dew-proof pipe 2 becomes large especially when the refrigerant circulation rate is 1.5 kg / hour or more. It is desirable to include a range that is longer than the time in the operation range P.

Further, in a home refrigerator equipped with a variable speed compressor, since the rotation speed of the compressor is 42 r / s or more and the refrigerant circulation rate exceeds 1.5 kg / hour under normal use conditions, the rotation speed is at least 42 r. The same effect can be expected even if it is defined as being in the operating range P when it is at least / s. Similarly, in a home refrigerator equipped with a variable speed compressor, the rotation speed of the compressor is 30 r / s or less and the refrigerant circulation rate is less than 1.5 kg / hour under normal use conditions. A similar effect can be expected even if the operating range Q is defined as being at least 30 r / s or less.

Then, from the outside air temperature, the temperature of each part of the refrigeration cycle, etc., it is estimated where the operating state of the refrigeration cycle is in the operating range indicated by P, Q, and R, and the above-described high load condition and normal condition, In addition, by performing the control under the low outside air temperature condition, it is possible to suppress the pressure loss and the heat load caused by the dew-proof pipe.

As described above, the refrigerator in the present embodiment is arbitrarily selected by connecting the first dew-proof pipe 1 and the second dew-proof pipe 2 in parallel via the flow path switching valve 3 on the downstream side of the main condenser 21. By doing so, the pressure loss and heat load resulting from the 1st dew-proof pipe 1 and the 2nd dew-proof pipe 2 are adjusted and controlled by the installation environment and operation state of the refrigerator.

Accordingly, the first dew-proof pipe 1 and the second dew-proof pipe 2 can be simultaneously used in parallel at the time of a high load with a large refrigerant circulation amount to reduce the refrigerant circulation amount and suppress the pressure loss. When the normal load is small, the first dew-proof pipe 1 is not used, and the heat load caused by the first dew-proof pipe 1 can be suppressed.

(Second Embodiment)
FIG. 6 is a longitudinal sectional view of a refrigerator according to the second embodiment of the present invention, FIG. 7 is a cycle configuration diagram of the refrigerator according to the second embodiment of the present invention, and FIG. 8 is a second embodiment of the present invention. FIG. 9 is a flowchart showing the control during defrosting of the refrigerator in the second embodiment of the present invention.

6 and 7, the refrigerator 11 includes a housing 12, a door 13, a leg 14 that supports the housing 12, a lower machine room 15 provided in a lower portion of the housing 12, and an upper portion provided in an upper portion of the housing 12. It has a machine room 16, a refrigeration room 17 disposed at the upper part of the casing 12, and a freezing room 18 disposed at the lower part of the casing 12. In addition, as components constituting the refrigeration cycle, a compressor 19 housed in the upper machine room 16, an evaporator 20 housed in the back side of the freezer room 18, and a main condenser 21 housed in the lower machine room 15 are provided. Have.

In addition, there are a partition wall 22 that partitions the lower machine chamber 15, a condenser fan 23 that is attached to the partition wall 22 to air-cool the main condenser 21, an evaporating dish 24 installed on the leeward side of the partition wall 22, and a bottom plate 25 of the lower machine chamber 15. is doing.

In addition, a plurality of air intakes 26 provided in the bottom plate 25, an exhaust port 27 provided on the back side of the lower machine room 15, and a communication air passage 28 connecting the exhaust port 27 of the lower machine room 15 and the upper machine room 16 are provided. is doing. Here, the lower machine chamber 15 is divided into two chambers by a partition wall 22, and a main condenser 21 is housed on the windward side of the condenser fan 23 and an evaporating dish 24 is housed on the leeward side.

Further, as the components constituting the refrigeration cycle, the dew-proof pipe 41 and the dew-proof pipe 41 which are located on the downstream side of the main condenser 21 and are thermally coupled to the outer surface of the housing 12 around the opening of the freezer compartment 18 are provided. It is located downstream, and has a dryer 42 that dries the circulating refrigerant, a throttle 42 that combines the dryer 42 and the evaporator 20 and depressurizes the circulating refrigerant.

In addition, an evaporator fan 30 that supplies cold air generated in the evaporator 20 to the refrigerator compartment 17 and the freezer compartment 18, a freezer damper 31 that blocks cold air supplied to the freezer compartment 18, and cold air supplied to the refrigerator compartment 17 The refrigerator compartment damper 32 to be shut off, the duct 33 for supplying cold air to the refrigerator compartment 17, the FCC temperature sensor 34 for detecting the temperature of the freezer compartment 18, the PCC temperature sensor 35 for detecting the temperature of the refrigerator compartment 17, and the upper part of the refrigerator compartment 17 It has a DFP temperature sensor 36 that is located and detects the temperature of the refrigerator compartment 17 above the PCC temperature sensor 35, and a heater 44 that is installed below the evaporator 20 and serves as an auxiliary heat source during defrosting. .

Here, the duct 33 is formed along a wall surface where the refrigerator compartment 17 and the upper machine room 16 are adjacent to each other, and a part of the cold air passing through the duct 33 is discharged from the vicinity of the center of the refrigerator compartment, and most of the cold air is in the upper machine. After passing through the wall 16 while cooling the adjacent wall surface, it is discharged from the upper part of the refrigerator compartment 17.

The operation of the refrigerator according to the second embodiment of the present invention configured as described above will be described below.

When the temperature detected by the DFP temperature sensor 36 rises to a predetermined ON temperature, the freezer damper 31 is closed with the compressor 19 stopped, the refrigerator damper 32 is opened, and the evaporator fan 30 is driven.

Thus, the refrigerator compartment 17 is cooled by utilizing the low-temperature sensible heat of the evaporator 20 and the frost adhering to the evaporator 20 and the latent heat of melting of the frost (this operation is hereinafter referred to as “off-cycle cooling”). When the temperature detected by the DFP temperature sensor 36 falls to a predetermined OFF temperature, the freezer damper 31 is closed, the refrigerator compartment damper 32 is closed, and the evaporator fan 30 is stopped (hereinafter, this operation is referred to as “cooling”). Stopped)).

When the temperature detected by the PCC temperature sensor 35 rises to a predetermined ON temperature during off-cycle cooling or cooling stop, the freezer damper 31 is closed, the refrigerator compartment damper 32 is opened, and the compressor 19 and the condenser fan 23 are opened. The evaporator fan 30 is driven.

When the condenser fan 23 is driven, the main condenser 21 side of the lower machine chamber 15 partitioned by the partition wall 22 has a negative pressure, and external air is sucked from the plurality of intake ports 26, and the evaporating dish 24 side has a positive pressure. The air in 15 is discharged to the outside through a plurality of discharge ports 27. The air discharged from the lower machine room 15 is sent to the upper machine room 16 via the communication air passage 28 to cool the compressor 19.

On the other hand, the refrigerant discharged from the compressor 19 is condensed while leaving a part of the gas while exchanging heat with the outside air in the main condenser 21 and then supplied to the dewproof pipe 41. The refrigerant that has passed through the dewproof pipe 41 dissipates heat through the housing 12 and condenses while warming the opening of the freezer compartment 18.

The liquid refrigerant that has passed through the dew-proof pipe 41 is moisture-removed by the dryer 42, depressurized by the throttle 43, and evaporated by the evaporator 20, while exchanging heat with the air in the refrigerator compartment 17 and cooling the refrigerator compartment 17. Then, it returns to the compressor 19 as a gaseous refrigerant (hereinafter, this operation is referred to as “PC cooling”).

Next, when the temperature detected by the PCC temperature sensor 35 falls to a predetermined OFF temperature or when the temperature detected by the FCC temperature sensor 34 rises to a predetermined ON temperature, the freezer damper 31 is opened and refrigerated. The chamber damper 32 is closed, and the compressor 19, the condenser fan 23, and the evaporator fan 30 are driven.

Hereinafter, by operating the refrigeration cycle similarly to the PC cooling, the freezer compartment 18 is heat-exchanged with the inside air of the freezer compartment 18 and the evaporator 20 to cool the freezer compartment 18 (this operation is hereinafter referred to as “FC cooling”). Next, when the temperature detected by the FCC temperature sensor 34 falls to a predetermined OFF temperature, the cooling stop operation is performed.

It should be noted that off-cycle cooling operates prior to cooling stop during cooling stop, and does not operate during PC cooling or FC cooling. In addition, PC cooling and FC cooling are operated with priority over off-cycle cooling.

Also, the OFF temperature at which off-cycle cooling is stopped is set higher than the ON temperature at which PC cooling is started. As a result, during normal operation, the basic operation is to repeat a series of operations of PC cooling, FC cooling, and cooling stop in order, and while the PC cooling and FC cooling operations are not performed, the cooling stop and off-cycle cooling are performed several times. Repeat repeatedly.

In FIG. 8, section a corresponds to PC cooling, section b corresponds to FC cooling, section c corresponds to off-cycle cooling, and section d corresponds to cooling stop operation. By this series of operations, the efficiency of the refrigeration cycle can be increased by keeping the temperature of the evaporator 20 at the time of PC cooling higher than that at the time of FC cooling, and the frost adhering to the evaporator 20 is melted by off-cycle cooling. By reusing latent heat, energy can be saved by reducing the capacity of the refrigeration cycle necessary for cooling the refrigerator compartment 17 while reducing heater power (not shown) during defrosting.

Further, based on the DFP temperature sensor 36 provided in the upper part of the refrigerating chamber 17 having a relatively large temperature change, the off-cooling is performed several times while the PC cooling operation and the FC cooling operation are not performed. Since the ratio between the off-cycle cooling and the PC cooling for cooling 17 can be accurately adjusted, the PC cooling operation time can be appropriately ensured.

In addition, as the detection temperature of the PCC temperature sensor 35 or the FCC temperature sensor 34 increases, even in the case of off-cycle cooling, this is stopped, and PC cooling or FC cooling is preferentially switched to PC cooling or FC cooling. An operation time can be ensured appropriately, and temperature changes in the refrigerator compartment 17 and the freezer compartment 18 can be suppressed.

Further, by setting the OFF temperature at which the off-cycle cooling is stopped higher than the ON temperature at which the PC cooling is started, the temperature of the DFP temperature sensor 36 provided in the upper part of the refrigerating chamber 17 having a relatively high temperature is set as the PCC temperature sensor. By controlling the off-cycle cooling while keeping it relatively high, the temperature change in the upper part of the refrigerator compartment 17 can be suppressed. In this embodiment, the OFF temperature at which off-cycle cooling is stopped is set higher than the ON temperature at which PC cooling is started, but the OFF temperature at which off-cycle cooling is stopped is the OFF temperature at which PC cooling is stopped. The same effect can be obtained even if the value is set higher than the above value.

Further, the duct 33 is formed on the wall surface of the refrigerating room 17 adjacent to the upper machine room 16 that is hotter than the outside air, thereby cooling the refrigerating room 17 during off-cycle cooling and PC cooling, particularly the refrigerating room 17. By raising the temperature of the cool air that cools the upper part of the refrigerator, it is possible to avoid overcooling of the upper part of the refrigerator compartment 17 and further suppress temperature fluctuations of the upper part of the refrigerator compartment 17, and Since cooling can be avoided, the amount of cool air that cools the refrigerator compartment 17 during PC cooling can be increased, and the efficiency of the heat exchange of the evaporator 20 can be improved to obtain higher refrigeration cycle efficiency during PC cooling. it can.

Then, after a normal operation consisting of a series of operations of PC cooling, FC cooling, off-cycle cooling, and cooling stop is continued for a predetermined time, the heater 44 for heating is used as necessary to remove frost attached to the evaporator 20. A relatively long period of off-cycle cooling is performed using this (this operation is hereinafter referred to as “off-cycle differential”). In FIG. 9, the control flow of the off-cycle differential is from “freezer compartment damper close” to “defrost completion determination”.

First, immediately before starting the PC cooling, when the normal operation exceeds a predetermined time, it is determined that “defrosting has started”. This is aimed at the timing when the temperature in the refrigerator compartment 17 is relatively high and the amount of heat is large in order to melt and remove the frost attached to the evaporator 20 using the amount of heat in the refrigerator compartment 17.

Then, the amount of food stored in the refrigerator compartment 17 is determined. When the amount of food is large, the heating heater 44 is not energized, and when the amount of food is small, the heating heater 44 is energized. Thereafter, as a series of operations of the off-cycle differential, the freezer compartment damper 31 is closed with the compressor 19 stopped, the refrigerator compartment damper 32 is opened, and the evaporator fan 30 is driven to defrost the evaporator 20. To implement.

Here, a method for estimating the amount of food stored in the refrigerator compartment 17 will be described. Since the PC cooling for mainly cooling the refrigerator compartment 17 is controlled based on the PCC temperature sensor 35, the average value of the temperature detected by the PCC temperature sensor 35 has a good correlation with the temperature of the food stored in the refrigerator compartment 17. is there.

On the other hand, as shown in FIG. 8, the DFP temperature sensor 36 for detecting the temperature of the upper part of the refrigerator compartment 17 is relatively higher than the PCC temperature sensor 35 in the modes (b, c, d) other than the PC cooling. Cooling (a) tends to approach the PCC temperature sensor 35. This is because cold air is mainly supplied from the upper part of the refrigerator compartment 17 through the duct 33.

As a result, when the amount of food stored in the refrigerator compartment 17 is relatively large and the heat capacity in the refrigerator compartment 17 is large, the total amount of cold air supplied from the upper part of the refrigerator compartment 17 becomes large, and the DFP temperature sensor 36 The temperature to be detected decreases to a temperature that is about the same as or lower than that of the PCC temperature sensor 35. On the other hand, when the amount of food stored in the refrigerator compartment 17 is relatively small and the heat capacity in the refrigerator compartment 17 is small, the temperature detected by the DFP temperature sensor 36 is lowered only to a temperature relatively higher than the PCC temperature sensor 35. do not do.

Therefore, for example, when the minimum value of the detected temperature of the DFP temperature sensor 36 during PC cooling is lower than the detected temperature of the PCC temperature sensor 35 at the same time by a predetermined value or more, the food stored in the refrigerator compartment 17 It can be determined that the amount is large. Similarly, the amount of food stored in the refrigerator compartment 17 can be determined from the difference in temperature behavior during off-cycle cooling, but the detection accuracy is excellent because the temperature change during PC cooling is greater.

The refrigerator in the present embodiment estimates the amount of food stored in the refrigerator compartment 17 based on the difference in temperature behavior during the PC cooling between the DFP temperature sensor 36 and the PCC temperature sensor 35. It is possible to directly estimate the amount of heat of the food stored in the container, and to adjust the output of the heating heater 44 with high accuracy.

And, when a DEF temperature sensor (not shown) for detecting the temperature of the evaporator 20 detects over 0 ° C., “defrosting completion determination”, that is, that the frost attached to the evaporator 20 has been completely removed. After the determination, the off-cycle differential operation is terminated, and the energization of the heating heater 44 is stopped, and then the normal operation is resumed.

With this off-cycle differential, especially when the amount of food stored in the refrigerator compartment 17 is large, the heating heater 44 is not used, and at the same time, the capacity of the refrigerating cycle necessary for cooling the refrigerator compartment 17 is reduced. Can save energy. At this time, since the amount of food stored in the refrigerator compartment 17 is large and the amount of heat necessary for defrosting the evaporator 20 can be ensured, the off-cycle differential can be completed in an appropriate time.

When the amount of food stored in the refrigerator compartment 17 is small due to the off-cycle differential, the heater 44 is used for heating, and the amount of food stored in the refrigerator compartment 17 and the power output from the heater 44 for heating are used. By using both of the quantities as heat sources, it is possible to reduce energy consumption by reducing the amount of power of the heater 44 for heating and reducing the capacity of the refrigeration cycle necessary for cooling the refrigerator compartment 17. At this time, it is possible to secure the amount of heat necessary for defrosting the evaporator 20 by supplementing the amount of heat of the food stored in the refrigerator compartment 17 with the amount of electric power output from the heater 44 for heating. The off-cycle differential can be terminated.

Note that the refrigerator in the present embodiment switches the heating heater 44 ON / OFF to adjust the heat source of the off-cycle differential, but when the amount of food stored in the refrigerator compartment 17 is large, the output is increased, If the amount of food stored in the refrigerator compartment 17 is small, the same effect can be expected even if the output is reduced and the output of the heating heater 44 is selected.

As described above, in the refrigerator having the off-cycle differential mode in which the evaporator 20 is defrosted while the refrigerator compartment 17 is cooled while the refrigerating cycle is stopped, the refrigerator in the present embodiment is before the off-cycle differential is performed. After detecting the amount of food stored in the refrigerated room and selecting the output of the heater for auxiliary use, the time required for the off-cycle differential can be appropriately controlled by performing the off-cycle differential. . In addition, the refrigerator in the present embodiment suppresses the temperature increase in the refrigerator compartment and the freezer compartment during off-cycle differential, and reduces the amount of power of the heating heater necessary for defrosting. Energy saving can be achieved.

(Third embodiment)
10 is a longitudinal sectional view of a refrigerator according to the third embodiment of the present invention, FIG. 11 is a cycle configuration diagram of the refrigerator according to the third embodiment of the present invention, and FIG. 12 is a third embodiment of the present invention. It is a wave form diagram of the temperature sensor behavior of the refrigerator.

10 and 11, the refrigerator 11 includes a housing 12, a door 13, legs 14 that support the housing 12, a lower machine room 15 provided in the lower portion of the housing 12, and an upper portion provided in the upper portion of the housing 12. It has a machine room 16, a refrigeration room 17 disposed at the upper part of the casing 12, and a freezing room 18 disposed at the lower part of the casing 12. In addition, as components constituting the refrigeration cycle, a compressor 19 housed in the upper machine room 16, an evaporator 20 housed in the back side of the freezer room 18, and a main condenser 21 housed in the lower machine room 15 are provided. Have. In addition, there are a partition wall 22 that partitions the lower machine chamber 15, a condenser fan 23 that is attached to the partition wall 22 to air-cool the main condenser 21, an evaporating dish 24 installed on the leeward side of the partition wall 22, and a bottom plate 25 of the lower machine chamber 15. is doing.

Further, as components constituting the refrigeration cycle, a dew-proof pipe 37 and a dew-proof pipe 37 which are located on the downstream side of the main condenser 21 and are thermally coupled to the outer surface of the housing 12 around the opening of the freezer compartment 18. It is located downstream, and has a dryer 38 that dries the circulating refrigerant, a throttle 38 that combines the dryer 38 and the evaporator 20 and depressurizes the circulating refrigerant.

In addition, an evaporator fan 30 that supplies cold air generated in the evaporator 20 to the refrigerator compartment 17 and the freezer compartment 18, a freezer damper 31 that blocks cold air supplied to the freezer compartment 18, and cold air supplied to the refrigerator compartment 17 The refrigerator compartment damper 32 to be shut off, the duct 33 for supplying cold air to the refrigerator compartment 17, the FCC temperature sensor 34 for detecting the temperature of the freezer compartment 18, the PCC temperature sensor 35 for detecting the temperature of the refrigerator compartment 17, the upper part of the refrigerator compartment 17, A DFP temperature sensor 36 for detecting the temperature of the refrigerator compartment 17 above the PCC temperature sensor 35 is provided.

The operation of the refrigerator according to the third embodiment of the present invention configured as described above will be described below.

When the temperature detected by the PCC temperature sensor 35 rises to a predetermined ON temperature during off-cycle cooling or cooling stop, the freezer damper 31 is closed, the refrigerator compartment damper 32 is opened, and the compressor 19 and the condenser fan 23 are opened. Drive. When the condenser fan 23 is driven, the main condenser 21 side of the lower machine chamber 15 partitioned by the partition wall 22 has a negative pressure, and external air is sucked from the plurality of intake ports 26, and the evaporating dish 24 side has a positive pressure. The air in 15 is discharged to the outside through a plurality of discharge ports 27. The air discharged from the lower machine room 15 is sent to the upper machine room 16 via the communication air passage 28 to cool the compressor 19.

On the other hand, the refrigerant discharged from the compressor 19 is condensed while leaving a part of the gas while exchanging heat with the outside air in the main condenser 21 and then supplied to the dewproof pipe 37. The refrigerant that has passed through the dew-proof pipe 37 radiates heat through the housing 12 and condenses while warming the opening of the freezer compartment 18. The liquid refrigerant that has passed through the dew-proof pipe 37 is dehydrated by the dryer 38, depressurized by the throttle 39, and is evaporated by the evaporator 20, while exchanging heat with the air in the refrigerator compartment 17 and cooling the refrigerator compartment 17. Then, it returns to the compressor 19 as a gaseous refrigerant (hereinafter, this operation is referred to as “PC cooling”).

Next, when the temperature detected by the PCC temperature sensor 35 falls to a predetermined OFF temperature or when the temperature detected by the FCC temperature sensor 34 rises to a predetermined ON temperature, the freezer damper 31 is opened and refrigerated. The chamber damper 32 is closed, and the compressor 19, the condenser fan 23, and the evaporator fan 30 are driven. Thereafter, by operating the refrigeration cycle in the same manner as PC cooling, the freezer compartment 18 is cooled by exchanging heat between the inside air of the freezer compartment 18 and the evaporator 20 (hereinafter, this operation is referred to as “FC cooling”). Next, when the temperature detected by the FCC temperature sensor 34 falls to a predetermined OFF temperature, the cooling stop operation is performed.

It should be noted that off-cycle cooling operates prior to cooling stop during cooling stop, and does not operate during PC cooling or FC cooling. In addition, PC cooling and FC cooling are operated with priority over off-cycle cooling. Further, the OFF temperature at which the off-cycle cooling is stopped is set higher than the ON temperature at which the PC cooling is started. As a result, during normal operation, the basic operation is to repeat a series of operations of PC cooling, FC cooling, and cooling stop in order, and while the PC cooling and FC cooling operations are not performed, the cooling stop and off-cycle cooling are performed several times. Repeat repeatedly.

In FIG. 12, section a corresponds to PC cooling, section b to FC cooling, section c to off-cycle cooling, and section d to cooling stop operation. By this series of operations, the efficiency of the refrigeration cycle can be increased by keeping the temperature of the evaporator 20 at the time of PC cooling higher than that at the time of FC cooling, and the frost adhering to the evaporator 20 is melted by off-cycle cooling. By reusing latent heat, energy can be saved by reducing the capacity of the refrigeration cycle necessary for cooling the refrigerator compartment 17 while reducing heater power (not shown) during defrosting.

Further, by setting the OFF temperature at which the off-cycle cooling is stopped higher than the ON temperature at which the PC cooling is started, the temperature of the DFP temperature sensor 36 provided in the upper part of the refrigerating chamber 17 having a relatively high temperature is set as the PCC temperature sensor By controlling the off-cycle cooling while keeping it relatively high, the temperature change in the upper part of the refrigerator compartment 17 can be suppressed.

In this embodiment, the OFF temperature at which off-cycle cooling is stopped is set higher than the ON temperature at which PC cooling is started, but the OFF temperature at which off-cycle cooling is stopped is the OFF temperature at which PC cooling is stopped. The same effect can be obtained even if the value is set higher than the above value.

Further, the duct 33 is formed on the wall surface of the refrigerating room 17 adjacent to the upper machine room 16 that is hotter than the outside air, thereby cooling the refrigerating room 17 during off-cycle cooling and PC cooling, particularly the refrigerating room 17. By raising the temperature of the cool air that cools the upper part of the refrigerator, it is possible to avoid overcooling the upper part of the refrigerator compartment 17 and further suppress the temperature fluctuation of the upper part of the refrigerator compartment 17. Furthermore, since overcooling of the upper part of the refrigerator compartment 17 can be avoided, the amount of cool air that cools the refrigerator compartment 17 during the PC cooling can be increased, and the heat exchange efficiency of the evaporator 20 can be improved to further increase the PC cooling. High refrigeration cycle efficiency can be obtained.

As described above, the refrigerator in the present embodiment has an off-cycle cooling mode (c) for cooling the refrigerator compartment 17 during the refrigeration cycle stop in addition to the FC cooling mode (b) and the PC cooling mode (a). In the refrigerator, independent of the control of the FC cooling mode (b) and the PC cooling mode (a), the DFP temperature is installed above the PCC temperature sensor 35 that controls the PC cooling and has a temperature change larger than that of the PCC temperature sensor 35. By controlling the off-cycle cooling mode (c) based on the temperature detected by the sensor 36, the off-cycle cooling time can be appropriately adjusted to ensure sufficient PC cooling time, and Temperature change can be suppressed.

(Fourth embodiment)
13 is a longitudinal sectional view of a refrigerator according to the fourth embodiment of the present invention, FIG. 14 is a cycle configuration diagram of the refrigerator according to the fourth embodiment of the present invention, and FIG. 15 is a fourth embodiment of the present invention. It is the figure which showed the state transition in the cooling control of the refrigerator, and its switching condition.

13 and 14, the refrigerator 11 includes a housing 12, a door 13, legs 14 that support the housing 12, a lower machine room 15 provided in the lower portion of the housing 12, and an upper portion provided in the upper portion of the housing 12. It has a machine room 16, a refrigeration room 17 disposed at the upper part of the casing 12, and a freezing room 18 disposed at the lower part of the casing 12.

In addition, as components constituting the refrigeration cycle, a compressor 19 housed in the upper machine room 16, an evaporator 20 housed in the back side of the freezer room 18, and a main condenser 21 housed in the lower machine room 15 are provided. Have. In addition, there are a partition wall 22 that partitions the lower machine chamber 15, a condenser fan 23 that is attached to the partition wall 22 to air-cool the main condenser 21, an evaporating dish 24 installed on the leeward side of the partition wall 22, and a bottom plate 25 of the lower machine chamber 15. is doing.

Here, the compressor 19 is a variable speed compressor and uses six stages of rotation speed selected from 20 to 80 r / s. This is because the refrigerating capacity is adjusted by switching the rotational speed of the compressor 19 to six stages from low speed to high speed while avoiding resonance of piping and the like. The compressor 19 operates at a low speed at the time of start-up, and increases as the operation time for cooling the refrigerator compartment 17 or the freezer compartment 18 becomes longer.

This is because the most efficient low speed is mainly used, and an appropriate relatively high rotational speed is used against an increase in load of the refrigerator compartment 17 or the freezer compartment 18 due to high outside air temperature, door opening / closing, or 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 the rotation speed at the start of the PC cooling mode with a high evaporation temperature and a relatively large refrigerating capacity is set to be higher than that in the FC cooling mode. It may be set low. Further, the refrigeration capacity may be adjusted while decelerating the compressor 19 as the temperature of the refrigerator compartment 17 or the freezer compartment 18 decreases.

In addition, an evaporator fan 30 that supplies cold air generated in the evaporator 20 to the refrigerator compartment 17 and the freezer compartment 18, a freezer damper 31 that blocks cold air supplied to the freezer compartment 18, and cold air supplied to the refrigerator compartment 17 In the refrigerator compartment damper 32 to be shut off, the duct 33 for supplying cold air to the refrigerator compartment 17, the FCC temperature sensor 34 for detecting the temperature of the freezer compartment 18, the PCC temperature sensor 35 for detecting the temperature of the refrigerator compartment 17, and the upper part of the refrigerator compartment 17 A DFP temperature sensor 36 for detecting the temperature of the refrigerator compartment 17 above the PCC temperature sensor 35 is provided.

The operation of the refrigerator according to the fourth embodiment of the present invention configured as described above will be described below.

In FIG. 15, arrows L1 to L15 indicate mode switching in the cooling control of the refrigerator in the fourth embodiment of the present invention. Here, the detailed description of the same cooling operation mode and mode switching conditions as those of the conventional refrigerator shown in FIG. 26 is omitted.

First, the off-cycle cooling mode will be described.

During the OFF mode, the condition of the arrow L1 (that is, the condition of the arrow M1) is satisfied, or the temperature detected by the DFP temperature sensor 36 rises to a predetermined DFP_ON temperature (that is, the condition of the arrow L10 is satisfied) To transition to the off-cycle cooling mode.

During the off-cycle cooling mode, the temperature detected by the FCC temperature sensor 34 does not exceed the predetermined FCC_ON temperature, the temperature detected by the PCC temperature sensor 35 does not exceed the predetermined PCC_ON temperature, and the DFP When the temperature detected by the temperature sensor 36 falls to a predetermined DFP_OFF temperature (that is, the condition indicated by the arrow L11 is satisfied), the mode transits to the OFF mode. Further, when the condition of the arrow L1 (that is, the condition of the arrow M1) is satisfied during the off-cycle cooling mode, the PC cooling mode is transitioned to.

Thus, the time in the off-cycle cooling mode can be appropriately adjusted using the DFP temperature sensor 36 installed in the upper part of the refrigerator compartment 17. Since the conventional refrigerator always performs off-cycle cooling for a certain time Td, there is a concern that the temperature of the refrigerator compartment 17 is unnecessarily lowered.

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

During the PC cooling mode, the temperature detected by the FCC temperature sensor 34 is higher than the predetermined FCC_OFF temperature, and the temperature detected by the PCC temperature sensor 35 falls to the predetermined PCC_OFF temperature (that is, the arrow L5 If the condition is satisfied), transition to the FC cooling mode. In addition, as noted in the condition of the arrow L5, the difference between the temperature detected by the FCC temperature sensor 34 and the FCC_OFF temperature of the predetermined value is detected by the PCC temperature sensor 35 after the predetermined time Tx1 has elapsed during the PC cooling mode. When the difference between the temperature to be used and the PCC_OFF temperature of the predetermined value is equal to or greater than, the transition to the FC cooling mode is made.

During the FC cooling mode, the temperature detected by the FCC temperature sensor 34 falls to a predetermined FCC_OFF temperature, and the temperature detected by the PCC temperature sensor 35 is equal to or higher than the predetermined PCC_ON temperature (that is, the condition indicated by the arrow L6). If satisfied, the PC cooling mode is entered. In addition, as described in the condition of the arrow L6, the difference between the temperature detected by the FCC temperature sensor 34 and the FCC_OFF temperature of the predetermined value is detected by the PCC temperature sensor 35 after the predetermined time Tx1 has elapsed during the FC cooling mode. When the temperature becomes equal to or less than the difference between the temperature to be measured and the PCC_OFF temperature of a predetermined value, the PC cooling mode is entered.

As a result, in an overload condition such as when the power is turned on when both the refrigerator compartment 17 and the freezer compartment 18 are at a high temperature, the PC cooling mode and the FC cooling mode are alternately switched every predetermined time Tx1, and the cooling is ended. It is possible to preferentially cool the one having a larger deviation from the OFF temperature. As a result, the cooling operation time can be distributed more flexibly than the time-fixed alternating cooling performed in the conventional refrigerator.

However, even if alternate cooling is performed with a degree of freedom in the cooling operation time, the freezer compartment 18 is intermittently cooled, and there is a concern that the upper limit of the storage temperature of frozen food such as ice cream may be exceeded. Therefore, an operation of cooling the refrigerator compartment 17 and the freezer compartment 18 at the same time (hereinafter, this operation is referred to as “simultaneous cooling mode”) is added only under an overload condition.

In the simultaneous cooling mode, the compressor 19, the condenser fan 23, and the evaporator fan 30 are driven by opening the freezer damper 31 and the refrigerator compartment damper 32. In the simultaneous cooling mode, when the condenser fan 23 is driven, the main condenser 21 side of the lower machine chamber 15 partitioned by the partition wall 22 has a negative pressure, and external air is sucked from the plurality of intake ports 26, and the compressor 19 The evaporating dish 57 side becomes positive pressure, and the air in the lower machine chamber 15 is discharged to the outside from the plurality of discharge ports 27.

On the other hand, the refrigerant discharged from the compressor 19 is condensed while leaving a part of the gas while exchanging heat with the outside air in the main condenser 21 and then supplied to the dewproof pipe 37. The refrigerant that has passed through the dew-proof pipe 37 radiates heat through the housing 12 and condenses while warming the opening of the freezer compartment 18. The liquid refrigerant that has passed through the dew-proof pipe 37 is water-removed by the dryer 38, depressurized by the throttle 39, and heat-exchanged with the air in the refrigerator compartment 17 and the freezer compartment 18 while being evaporated by the evaporator 20, and the refrigerator compartment 17 And while cooling the freezer compartment 18, it recirculate | refluxs to the compressor 19 as a gaseous refrigerant.

At this time, the evaporator fan 30 is rotated at a high speed to secure an 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 that has a high wind speed at a high temperature flows into the evaporator 20, so that the temperature of the blown air from the evaporator 20 tends to rise. It is desirable to ensure proper refrigeration capacity by operating When the compressor 19 is operated at a low speed in the simultaneous cooling mode, there is a concern that the temperature of the air blown from the evaporator 20 increases and the freezer compartment 18 cannot be cooled to a low temperature.

Therefore, when the rotation speed of the compressor 19 is equal to or higher than the predetermined rotation speed during the PC cooling mode (that is, the condition of the arrow L12 is satisfied), the mode is changed to the simultaneous cooling mode and the compressor is moved during the simultaneous cooling mode. When the rotational speed of 19 is less than the predetermined rotational speed (that is, the condition of the arrow L13 is satisfied), the PC cooling mode is entered.

Also, the mode switching between the arrow L12 and the arrow L13 is performed with priority over other state transitions. This is because the rotation speed of the compressor 19 is increased to a predetermined rotation speed or more, so that it is detected that the refrigerator 11 is in an overload condition and the mode is changed to the simultaneous cooling mode. This is to avoid that the temperature of the air blown from the evaporator 20 rises and the freezer compartment 18 cannot be cooled to a low temperature when the rotation speed is less than the predetermined number of revolutions.

Further, during the simultaneous cooling mode, the temperature detected by the PCC temperature sensor 35 falls below a predetermined value of PCC_OFF temperature, or the temperature detected by the FCC temperature sensor 34 is higher than the FCC_ON temperature after a predetermined time Tx5 has elapsed. When the temperature is equal to or higher than the FCC_LIM temperature of a predetermined value (that is, the condition of the arrow L14 is satisfied), the mode is changed to the FC cooling mode. This is to continue the simultaneous cooling mode up to the upper temperature limit at which the freezer compartment 18 is allowed in order to suppress the temperature rise of the refrigerator compartment 17 that is not cooled during the FC cooling mode.

Therefore, it is desirable that the FCC_LIM temperature detected by the FCC temperature sensor 34 is a predetermined value corresponding to weak cooling that is 2 to 5 ° C. higher than the FCC_ON temperature, which is the upper limit temperature during normal cooling.

In the present embodiment, the condition of the arrow L12 for transitioning to the simultaneous cooling mode corresponding to the overload condition is defined by the number of revolutions of the compressor 19. However, when the power is turned on at high outside air temperature and the door is frequently opened and closed. May be detected and a transition to the simultaneous cooling mode may be made.

If it is clear that the compressor 11 is in an overload condition without increasing the speed of the compressor 19, it is possible to shift to the simultaneous cooling mode sooner.

In this case, the condition of the arrow L13 may be changed so that the simultaneous cooling mode is canceled by detecting that the temperature of the refrigerator compartment 17 or the freezer compartment 18 is lowered to some extent. As a result, like the present embodiment, the most efficient PC cooling mode can be used for a longer time.

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

During the simultaneous cooling mode, the temperature detected by the FCC temperature sensor 34 indicates a temperature lower than the predetermined FCC_LIM temperature, and the temperature detected by the PCC temperature sensor 35 indicates a temperature higher than the predetermined PCC_OFF temperature. After the elapse of a predetermined time Tx6 from the start of the cooling mode, when the difference between the temperature detected by the PCC temperature sensor 35 and the temperature detected by the DFP temperature sensor 36 is equal to or less than the predetermined value α (that is, the condition of the arrow L15 is satisfied) Transition to defrost mode.

When the evaporator 20 is frosted during the simultaneous cooling mode and the refrigerating chamber 17 tends to be slowly cooled, normal defrost performed every predetermined time Tx2 is performed earlier. By reducing the defrosting interval, the cooling capacity of the refrigerator compartment 17 can be recovered early.

In the simultaneous cooling mode, the evaporator fan 30 is rotated at a high speed to secure the amount of air sent in parallel to both the refrigerator compartment 17 and the freezer compartment 18, but when a large amount of frost is formed in the evaporator 20. The sufficient air volume cannot be secured. At this time, compared with the freezer compartment 18 formed immediately before the evaporator 20, the air volume in the refrigerator compartment 17 having a relatively long path for blowing air from the evaporator 20 is greatly reduced, and the cold air in the upper part of the refrigerator compartment 17 is reduced. The temperature difference between the DFP temperature sensor 36 that is relatively close to the blowing position and the PCC temperature sensor 35 near the center of the refrigerator compartment 17 becomes smaller than the predetermined value α.

Therefore, by utilizing the difference between the temperature detected by the PCC temperature sensor 35 and the temperature detected by the DFP temperature sensor 36, the cooling state of the refrigerator compartment 17 in the simultaneous cooling mode is normal or the evaporator 20 is attached. It can be detected whether the refrigeration room 17 has a slow cooling tendency due to frost, and when the refrigeration room 17 has a slow cooling tendency, the cooling capacity of the refrigeration room 17 is quickly recovered by reducing the defrosting interval of the evaporator 20. can do.

As described above, the refrigerator in the present embodiment is a refrigerator having an off-cycle cooling mode that cools the refrigerator compartment while the refrigeration cycle is stopped in addition to the FC cooling mode and the PC cooling mode. By realizing this mode, while maintaining a highly efficient PC cooling mode as much as possible, the amount of cooling in the freezer and freezer compartments can be adjusted automatically and appropriately under overload conditions, thereby increasing the temperature of the refrigerator compartment and freezer compartment. Can be suppressed.

(Fifth embodiment)
FIG. 16 is a longitudinal sectional view of a refrigerator in the fifth embodiment of the present invention. FIG. 17 is a diagram showing the relationship between the interval of the defrosting mode of the refrigerator and the accumulated time of the off-cycle cooling mode in the fifth embodiment of the present invention. FIG. 18 is a diagram showing the relationship between the interval of the defrosting mode of the refrigerator and the integrated door opening time in the fifth embodiment of the present invention. FIG. 19 is a diagram showing the relationship between the interval of the defrosting mode of the refrigerator and the outside air humidity in the fifth embodiment of the present invention. FIG. 20 is a diagram showing the relationship between the interval of the defrosting mode of the refrigerator and the internal temperature setting in the fifth embodiment of the present invention.

As shown in FIG. 16, the refrigerator in the present embodiment has a freezer compartment door 113 that seals the opening of the freezer compartment 102 so that it can be opened and closed, and a refrigerator compartment door 114 that seals the opening of the refrigerator compartment 103 so that it can be opened and closed.

In addition, in the openings 102a and 103a of the freezer compartment 102 and the refrigerator compartment 103, the opening and closing of the freezer compartment door 113 and the refrigerator compartment door 114 are detected, for example, a freezer compartment door sensor 115 composed of a Hall IC and a magnet and the refrigerator compartment. A door sensor 116 is provided.

Further, a humidity sensor 117 for detecting the humidity of the outside air is provided on the outer wall side of the refrigerator 101, and the operation of the refrigeration cycle is controlled inside, the control state of the refrigeration cycle, the freezer compartment door sensor 115, the refrigerator compartment. A control unit 118 that performs operation control of the refrigeration cycle based on the outputs of the door sensor 116 and the humidity sensor 117 is provided.

About the refrigerator comprised as mentioned above, the operation | movement is demonstrated using FIGS. 17-20.

30. During normal cooling, when the compressor 104 is stopped in step S12 shown in FIG. 30, if the operation time tcomp of the compressor 104 is tdefrost or more in step S13, the process proceeds to step S18 shown in FIG.

Tdefrost has a certain initial value tdefrostb and fluctuates depending on the off-cycle cooling time, door opening / closing time, outside air humidity, and internal temperature setting.

First, the relationship between the off-cycle cooling time and tdefrost will be described with reference to FIG. During off-cycle cooling, the refrigerator compartment 107 is closed, the refrigerator compartment damper 108 is opened, and the cooling fan 106 is operated to cool the refrigerator compartment 103 using latent heat or sensible heat of frost attached to the cooler 105. At the same time, heat is taken away from the frost adhering to the cooler 105. For this reason, the amount of heat necessary for defrosting the cooler 105 decreases as the off-cycle cooling time increases.

On the other hand, the integration time of off-cycle cooling is counted by the control unit 118, and is controlled by the control unit 118 so that tdefrost becomes longer as the integration time becomes longer. Thereby, tdefrost can be changed according to the degree of frost formation on the cooler 105 due to the accumulated time of off-cycle cooling, the number of operations in the defrosting mode can be optimized, and the temperature rise in the warehouse is appropriately prevented. be able to.

Next, the relationship between the door opening / closing time and tdefrost will be described with reference to FIG. During the operation of the refrigerator, the freezer compartment door 113 or the refrigerator compartment door 114 is opened and closed to take out food in the storage compartment. At this time, high-temperature and high-humidity outside air flows into the storage chamber as compared to the storage chamber air dehumidified and circulated by the cooler 105. When the high-temperature and high-humidity air that has flowed into the refrigerator passes through the cooler 105 by the operation of the cooling fan 106, frost formation on the cooler 105 occurs. Therefore, if the door opening / closing time is long, the amount of frost formation on the cooler 105 increases, and conversely, if the door opening / closing time is short, the amount of frost formation decreases.

On the other hand, the door opening integration time is counted by the freezer compartment door sensor 115 and the refrigerator compartment door sensor 116, and is output to the control unit 118. In the control unit 118, the longer the door opening / closing integration time, the shorter the tdefrost becomes. I have control. Thereby, tdefrost can be changed in accordance with the degree of frost formation on the cooler 105 based on the door opening / closing integrated time, the number of operations in the defrosting mode can be optimized, and the temperature rise in the warehouse can be appropriately prevented. it can.

Next, the relationship between the outside air humidity and tdefrost will be described with reference to FIG. The freezer compartment 102 and the refrigerator compartment 103 are hermetically sealed by the freezer compartment door 113 and the refrigerator compartment door 114, but are not completely sealed, and have a minute gap from which indoor and outdoor air can flow. The humidity of the outside air flows into the cabinet.

Also, as described above, the humidity of the outside air flows into the room when the door is opened and closed. Therefore, when the outside air humidity is high, the humidity entering the compartment is also high, and the amount of frost formation on the cooler 105 is increased. Conversely, when the outside air humidity is low, the amount of frost formation is reduced.

On the other hand, the outside air humidity is measured by the humidity sensor 117, and the average humidity from the fully-open defrost mode is calculated and output to the control unit 118. The control is performed so that the higher the outside air humidity is, the shorter the tdefrost becomes. This is controlled by the unit 118. Thereby, tdefrost can be changed according to the degree of frost formation on the cooler 105 due to the outside air humidity, the number of operations in the defrost mode can be optimized, and the temperature rise in the warehouse can be appropriately prevented.

Next, the relationship between the internal temperature setting and tdefrost will be described with reference to FIG. When the temperature settings of the freezer compartment 102 and the refrigerator compartment 103 are lowered, the internal air temperature is lowered, and the temperature of the cooler 105 is lowered accordingly. When the temperature of the cooler 105 is lowered, the amount of dehumidification from the passing internal air increases, and the frost on the cooler 105 also increases. On the contrary, when the temperature setting is increased, the temperature of the cooler 105 is increased, so that the amount of dehumidification is reduced and frost formation on the cooler 105 is reduced.

On the other hand, the internal temperature setting is detected by the control unit 118, and is controlled by the control unit 118 so that the higher the internal temperature setting, the longer tdefrost becomes. Thereby, tdefrost can be changed according to the degree of frost formation on the cooler 105 by the internal temperature setting, the number of operations in the defrosting mode can be optimized, and the internal temperature can be prevented appropriately. it can.

As described above, the refrigerator in the present embodiment can prevent a temperature rise in the refrigerator, and thus can be a refrigerator with high cooling performance.

In the present embodiment, tdefrost is described as a control method in which proportional control is performed with respect to the increase / decrease of each control factor. The effect is obtained, and there is an advantage that the control becomes simple.

In the present embodiment, the off-cycle cooling is controlled to be terminated by the temperature detected by the cold room sensor 110. However, the off-cycle cooling may be controlled by, for example, determining the off-cycle cooling time or by other control factors. Similar effects can be obtained.

In the present embodiment, the refrigerator is described as two refrigerators, a freezer compartment 102 and a refrigerator compartment 103, but the same control is performed regardless of the number of storage compartments, such as a three-room refrigerator equipped with a vegetable compartment. Similar effects can be obtained.

Further, in the present embodiment, the control for detecting the outside air humidity has been described. However, by measuring the outside air humidity and the outside air temperature and performing the control for changing the tdefrost with respect to the outside air temperature, more optimal control can be performed. It can be carried out.

Moreover, although the refrigerator in this Embodiment demonstrated by the specification which produces | generates cold air with the refrigerant | coolant compression-type refrigeration cycle using the compressor 104, if it is a refrigeration system which produces | generates cold air with the cooler 105, what kind of refrigeration system is used. Even if it is, the same effect can be obtained.

As described above, the present invention includes a forced air-cooled main condenser, a flow path switching valve connected to the downstream side of the main condenser, and a plurality of parallel connection downstream of the flow path switching valve. The refrigerator has a dew-proof pipe and flows a refrigerant in parallel to the plurality of dew-proof pipes at high load.

Further, the present invention is a refrigerator characterized in that when the refrigeration cycle is operated under normal conditions, the number of dew-proof pipes used is smaller than that under high load.

This makes it possible to reduce the number of dew-proof pipes used during normal loads with a small amount of refrigerant circulation and to suppress the heat load caused by the dew-proof pipes. Here, the normal load is assumed to be when the door is not opened and closed for a long time, for example, in the autumn to spring when the temperature and humidity of the outside air are relatively low. In such a case, the operating rate of the refrigeration cycle decreases. As a result, the circulation rate of the refrigerant decreases, and it is almost unnecessary to prevent condensation around the refrigerator housing in which the dew-proof pipe is provided.

At this time, by selecting and using a part of the dew proof pipe, the heat load caused by the dew proof pipe can be suppressed. In particular, when the humidity of the outside air is low and it is not necessary to prevent condensation around the opening of the refrigerator, condensation is likely to occur in the gap with the surrounding wall like the back of the refrigerator, and the heat in the cabinet is relatively high in heat insulation. By selecting a dew-proof pipe disposed in a place where it is difficult to become a load, the thermal load can be more efficiently suppressed.

Further, the present invention is a refrigerator characterized in that the inner diameter of the pipe of the main condenser is 4 mm or more and the inner diameter of the dew proof pipe is less than 4 mm. The pressure loss can be reduced by increasing the pipe inner diameter of the condenser to 4 mm or more, and the refrigerant volume can be suppressed by reducing the internal volume by reducing the inner diameter of the dew-proof pipe having a high ratio of liquid refrigerant to less than 4 mm. .

In particular, by reducing the internal volume of the dew-proof pipe, it is possible to reduce the amount of refrigerant that stays in the non-use dew-proof pipe when multiple dew-proof pipes are switched to the non-use state. The problem of insufficient refrigerant amount can be avoided.

Further, the present invention is a refrigerator characterized in that the user manually selects a dew-proof pipe to be used when operated under normal conditions. By using only a part of the dew-proof pipe, the heat load caused by the dew-proof pipe can be arbitrarily adjusted and suppressed more efficiently.

Further, the present invention is a refrigerator characterized by stopping the air cooling fan of the main condenser when operated under a low outside air temperature condition and using a plurality of dew pipes. The problem of insufficient circulating refrigerant amount in the refrigeration cycle due to excessive refrigerant retention can be avoided.

In addition, as described above, the present invention includes a refrigerator compartment, a freezer compartment, a refrigeration cycle, an evaporator that is a component of the refrigeration cycle, and cool air generated in the evaporator to the refrigerator compartment and the refrigerator. An evaporator fan to be supplied to the room, a heater for defrosting the evaporator, a refrigerating room damper for shutting off cool air supplied from the evaporator to the refrigerating room, and a freezer from the evaporator In a refrigerator having a freezer damper for shutting off cool air supplied to a room, the freezer damper is opened, the refrigerating room damper is closed, and the cold air generated in the evaporator is operated while operating the refrigerating cycle. FC cooling mode for supplying and cooling the freezer compartment, closing the freezer compartment damper, opening the refrigerating compartment damper, supplying cold air generated in the evaporator while operating the refrigerating cycle PC cooling mode for cooling the refrigerator compartment, closing the freezer damper, opening the refrigerator compartment damper, and operating the evaporator fan while stopping the refrigeration cycle, thereby the evaporator and the refrigerator The off-cycle cooling mode for exchanging heat of indoor air, the evaporator while closing the freezer compartment damper and opening the refrigerating compartment damper while energizing the heater for heating, and stopping the refrigerating cycle After operating the fan, it has an off-cycle differential mode that melts and removes frost attached to the evaporator, and after selecting the output of the heater for heating based on the amount of food stored in the refrigerator compartment Since the refrigerator is characterized by performing the off-cycle differential mode, the time required for the off-cycle differential can be properly controlled, and the off-cycle differential is being performed. It suppresses that built chamber and the freezing chamber is increased temperatures, it is possible to achieve energy saving of the refrigerator by reducing the amount of power of the warming heater required defrosting.

Further, the present invention is a refrigerator characterized by determining whether or not the off-cycle differential mode can be performed immediately before the start of the PC cooling mode. Therefore, the refrigerator is turned off at a relatively high temperature immediately before the refrigerator compartment is cooled. The cycle differential mode can be carried out, and the amount of heat of the off-cycle differential supplied to the evaporator can be increased to further reduce the electric energy of the heating heater necessary for defrosting.

The present invention also includes a PCC temperature sensor that detects the temperature of the refrigerator compartment, and a DFP temperature sensor that is installed above the PCC temperature sensor and detects the temperature of the upper portion of the refrigerator compartment. The refrigerator is characterized by detecting the amount of food stored in the refrigeration room based on the difference in temperature change between the PCC temperature sensor and the DFP temperature sensor in the cycle cooling mode. The amount of heat of the heated food can be directly estimated, and the power of the heating heater necessary for defrosting can be further reduced by accurately adjusting the output of the heating heater.

In addition, as described above, the present invention includes a refrigerator compartment, a freezer compartment, a refrigeration cycle, an evaporator that is a component of the refrigeration cycle, and cool air generated in the evaporator to the refrigerator compartment and the refrigerator. An evaporator fan supplied to the chamber, a refrigerator compartment damper for shutting off cool air supplied from the evaporator to the refrigerator compartment, a freezer compartment damper for shutting off cool air supplied from the evaporator to the freezer compartment, An FCC temperature sensor that detects the temperature of the freezer, a PCC temperature sensor that detects the temperature of the refrigerator compartment, and a DFP temperature sensor that is installed above the PCC temperature sensor and detects the temperature of the upper portion of the refrigerator compartment. In the refrigerator, the freezer damper is opened, the refrigerator compartment damper is closed, and the freezer generated by the evaporator is supplied to cool the freezer while operating the refrigerating cycle. FC cooling mode, PC cooling mode in which the freezer compartment damper is closed, the refrigerating compartment damper is opened, and cold air generated in the evaporator is supplied while the refrigerating cycle is operated to cool the refrigerating compartment And closing the freezer damper, opening the refrigerator compartment damper, and operating the evaporator fan while stopping the refrigeration cycle, thereby exchanging heat between the evaporator and the air in the refrigerator compartment. A cycle cooling mode, and on / off of the FC cooling mode and the PC cooling mode is determined based on the detected temperature of the FCC temperature sensor or the PCC temperature sensor, and based on the detected temperature of the DFP temperature sensor. Since the refrigerator is characterized by determining whether the off-cycle cooling mode is on or off, the PC cooling operation time can be appropriately confirmed. It can be.

This is because the off-cycle cooling operation time is controlled based on the DFP temperature sensor provided in the upper part of the refrigerating room where the temperature change is relatively large, thereby accurately adjusting the ratio of off-cycle cooling to cool the refrigerating room and PC cooling Therefore, the PC cooling operation time can be appropriately secured.

In the refrigerator, the FC cooling mode and the PC cooling mode are prioritized over the off-cycle cooling mode when the temperature detected by the FCC temperature sensor or the PCC temperature sensor rises. Therefore, it is possible to suppress a decrease in the operation time of PC cooling and FC cooling due to off-cycle cooling, and it is possible to suppress temperature changes in the refrigerator compartment and the freezer compartment. This is because the PCC temperature sensor or FCC temperature sensor operation is stopped by switching to PC cooling or FC cooling by preferentially switching to PC cooling or FC cooling even if it is off-cycle cooling as the temperature detected by the PCC temperature sensor or FCC temperature sensor rises. Time can be secured appropriately and temperature changes in the refrigerator compartment and the freezer compartment can be suppressed.

Further, the present invention sets the OFF temperature of the DFP temperature sensor that detects the end of the off-cycle cooling mode to a temperature higher than the ON temperature of the PCC temperature sensor that detects the start of the PC cooling mode. Therefore, the overcooling of the upper part of the refrigerator compartment due to off-cycle cooling can be suppressed, and the temperature change of the upper part of the refrigerator compartment can be suppressed. This suppresses the temperature change of the upper part of the refrigerator compartment by controlling off-cycle cooling while keeping the temperature of the DFP temperature sensor provided in the upper part of the refrigerator compartment having a relatively high temperature relatively higher than that of the PCC temperature sensor. It is something that can be done.

In addition, the present invention provides a compressor that is a component of a refrigeration cycle, an upper machine room that houses the compressor, and is disposed above the refrigeration room, and is adjacent to the upper machine room and cools the refrigeration room. Since the refrigerator has a duct through which the cool air flows, the temperature of the cool air for cooling the refrigerating room can be increased, and temperature fluctuations in the upper part of the refrigerating room can be further suppressed. This is because a duct is formed on the wall of the refrigeration room adjacent to the upper machine room that is hotter than the outside air, thereby cooling the refrigeration room, especially the upper part of the refrigeration room, during off-cycle cooling and PC cooling. By raising the temperature of the cold air to be heated, overcooling of the upper part of the refrigerator compartment can be avoided and temperature fluctuations of the upper part of the refrigerator compartment can be further suppressed. In addition, since overcooling of the upper part of the refrigerator compartment can be avoided, it is possible to increase the amount of cool air that cools the refrigerator compartment during PC cooling, improving the heat exchange efficiency of the evaporator, and increasing the refrigeration cycle during PC cooling. Efficiency can be obtained.

In addition, as described above, the present invention includes a refrigerator compartment, a freezer compartment, a refrigeration cycle, an evaporator that is a component of the refrigeration cycle, and cool air generated in the evaporator to the refrigerator compartment and the refrigerator. An evaporator fan supplied to the chamber, a refrigerator compartment damper for shutting off cool air supplied from the evaporator to the refrigerator compartment, a freezer compartment damper for shutting off cool air supplied from the evaporator to the freezer compartment, An FCC temperature sensor that detects the temperature of the freezer, a PCC temperature sensor that detects the temperature of the refrigerator compartment, and a DFP temperature sensor that is installed above the PCC temperature sensor and detects the temperature of the upper portion of the refrigerator compartment. In the refrigerator, the freezer damper is opened, the refrigerator compartment damper is closed, and the freezer generated by the evaporator is supplied to cool the freezer while operating the refrigerating cycle. FC cooling mode, PC cooling mode in which the freezer compartment damper is closed, the refrigerating compartment damper is opened, and cold air generated in the evaporator is supplied while the refrigerating cycle is operated to cool the refrigerating compartment A simultaneous cooling mode in which the freezer compartment damper is opened, the refrigerator compartment damper is opened, and cold air generated in the evaporator is supplied while the refrigerating cycle is operated to cool the freezer compartment and the refrigerator compartment at the same time. And closing the freezer damper, opening the refrigerator compartment damper, and operating the evaporator fan while stopping the refrigeration cycle, thereby exchanging heat between the evaporator and the air in the refrigerator compartment. Cycle cooling mode. In normal conditions, FC cooling mode, PC cooling mode, and off-cycle cooling mode are combined for cooling, and in overload conditions, simultaneous cooling mode is used. This is a combination of FC cooling mode. In normal conditions, the highly efficient PC cooling mode is maintained as much as possible. In overload conditions, the freezer compartment and the refrigerator compartment are automatically cooled while continuing to cool down. Therefore, the temperature can be adjusted appropriately and the temperature increase in the refrigerator compartment and the freezer compartment can be suppressed.

The present invention also includes a variable speed compressor, and when the compressor is less than a predetermined number of revolutions, cooling is performed by combining an FC cooling mode, a PC cooling mode, and an off-cycle cooling mode, and the compressor is at least a predetermined number of revolutions. Then, the cooling is performed by combining the simultaneous cooling mode and the FC cooling mode, and the temperature rise of the evaporator in the simultaneous cooling mode can be suppressed, so that the cooling capacity shortage of the freezer can be suppressed.

Further, the present invention sets the reference temperature of the FCC temperature sensor when switching from the simultaneous cooling mode to the FC cooling mode higher than the reference temperature of the FCC temperature sensor when starting the cooling operation. The simultaneous cooling mode can be maintained as much as possible to the upper limit of the allowable temperature, and insufficient cooling capacity of the refrigerator compartment can be suppressed.

In addition, the present invention detects the slowing of the cooling rate of the refrigerator compartment from the temperature behavior of the PCC temperature sensor and the DFP temperature sensor, and shortens the defrosting interval of the evaporator. It is possible to recover the decrease in the air volume of the refrigerator in the mode at an early stage, and it is possible to suppress an insufficient cooling capacity of the refrigerator.

Further, as described above, the refrigerator of the present invention includes a first storage chamber having an opening on the front surface, a second storage chamber having an opening on the front surface, and a cooler that generates cold air. A refrigeration cycle, a cooling fan that circulates the cool air generated by the cooler to the first storage chamber and the second storage chamber, and a first damper that selectively flows the cool air from the cooling fan to the first storage chamber And a second damper for selectively flowing cool air from the cooling fan to the second storage chamber, and a defrost heater for defrosting the frost adhering to the cooler by heat. When the refrigeration cycle is stopped, the cooling fan is Operates and releases the first damper or the second damper to cool the first storage chamber or the second storage chamber, and the defrost heater defrosts the frost attached to the cooler. In refrigerators equipped with a defrost mode, the end of the defrost mode It has a configuration which is characterized by controlling the interval until the next defrosting mode from.

This configuration makes it possible to adjust the defrosting interval by predicting the amount of frost attached to the cooler in a refrigerator equipped with a freezer damper. Thereby, the useless temperature rise of a storage room can be prevented.

The refrigerator of the present invention is characterized in that the interval until the next defrost mode is controlled by the number of off-cycle cooling modes from the end of the defrost mode.

This configuration makes it possible to adjust the defrost interval by predicting the amount of frost formation based on the number of off-cycle cooling modes. Thereby, the useless temperature rise of a storage room can be prevented.

Further, the refrigerator of the present invention is characterized in that the interval until the next defrost mode is controlled by the accumulated time of the off-cycle cooling mode from the end of the defrost mode.

This configuration makes it possible to adjust the defrost interval by predicting the amount of frost formation based on the accumulated time in the off-cycle cooling mode. Thereby, the useless temperature rise of a storage room can be prevented.

Further, the refrigerator of the present invention includes a first door and a second door, and an opening of the first storage chamber and the second storage chamber. A door opening / closing detection means for detecting opening and closing, and the interval until the next defrosting mode is controlled by the number of times the first door and the second door are opened after the defrosting mode ends. It is said.

This configuration makes it possible to adjust the defrosting interval by predicting the amount of frost formation based on the combination of the number of times of opening and closing the door and the number of times of the off cycle cooling mode or the time. Thereby, while being able to prevent the frost residue of a cooler, the useless temperature rise of a storage chamber can be prevented.

Further, the refrigerator of the present invention includes a first door and a second door, and an opening of the first storage chamber and the second storage chamber. And a door opening / closing detection means for detecting opening and closing, and the interval until the next defrosting mode is controlled by the integrated opening time of the first door and the second door from the end of the defrosting mode. It is configured.

This configuration makes it possible to adjust the defrost interval by predicting the amount of frost formation based on the combination of the door opening time and the number of off-cycle cooling modes or the time. Thereby, while being able to prevent the frost residue of a cooler, the useless temperature rise of a storage chamber can be prevented.

Further, the refrigerator of the present invention is configured to include humidity detection means for detecting the humidity around the refrigerator, and to control the interval until the next defrosting mode according to the humidity detected by the humidity detection means. .

This configuration makes it possible to adjust the defrosting interval by predicting the amount of frost formation based on the combination of the humidity around the refrigerator, the number or time of the off-cycle cooling mode, the number of times the door is opened and closed, or the total opening time. Thereby, while being able to prevent the frost residue of a cooler, the useless temperature rise of a storage chamber can be prevented.

The refrigerator of the present invention is provided with first temperature adjusting means and second temperature adjusting means for setting the temperatures of the first storage chamber and the second storage chamber, and the first temperature adjusting means and the second temperature adjusting means. The interval until the next defrosting mode is controlled by the set temperature of the temperature adjusting means.

With this configuration, the defrosting interval can be adjusted by predicting the amount of frost formation by a combination of the temperature setting of the refrigerator, the humidity around the refrigerator, the number or time of the off-cycle cooling mode, and the number of times the door is opened or closed or the total opening time. . Thereby, while being able to prevent the frost residue of a cooler, the useless temperature rise of a storage chamber can be prevented.

As described above, the refrigerator according to the present invention has a plurality of dew-proof pipes connected in parallel to the downstream side of the main condenser via the flow path switching valve, so that the dew-proof pipes can be used depending on the installation environment and operation state of the refrigerator. Since the resulting pressure loss and thermal load can be adjusted arbitrarily, it can be applied to other refrigeration application products such as commercial refrigerators.

The refrigerator according to the present invention is housed in the refrigerator compartment in the refrigerator having the off-cycle cooling mode and the off-cycle differential mode in which the refrigerator compartment is cooled while the refrigeration cycle is stopped in addition to the FC cooling mode and the PC cooling mode. By adjusting the output of the heater for heating based on the amount of food, the off-cycle differential time can be adjusted appropriately, so that it can also be applied to other refrigerated products such as commercial refrigerators.

In addition, the refrigerator according to the present invention, in addition to the FC cooling mode and the PC cooling mode, appropriately secures the PC cooling operation time in the refrigerator having the off-cycle cooling mode for cooling the refrigerator compartment while the refrigeration cycle is stopped. Since the temperature change in the refrigerator compartment can be suppressed, it can be applied to other refrigerator-freezer products such as commercial refrigerators.

In addition to the FC cooling mode and the PC cooling mode, the refrigerator according to the present invention realizes the simultaneous cooling mode only in an overload condition in a refrigerator having an off-cycle cooling mode for cooling the refrigerator compartment while the refrigeration cycle is stopped. Thus, while maintaining a high-efficiency PC cooling mode as much as possible, the temperature rise of the refrigerator compartment or freezer compartment under overload conditions can be suppressed, so that it can be applied to other refrigerator-freezer application products such as commercial refrigerators.

Moreover, this invention can provide the refrigerator which cools a storage room efficiently by changing the space | interval of a defrost operation in the refrigerator which cools the inside of a refrigerator when a compressor stops. Therefore, the present invention is useful as refrigerators of various types and sizes such as home use and business use.

DESCRIPTION OF SYMBOLS 1 1st dew-proof pipe 2 2nd dew-proof pipe 3 Flow path switching valve 4 Junction point 5 Dryer 6 Restriction 11 Refrigerator 12 Case 13 Door 14 Leg 15 Lower machine room 16 Upper machine room 17 Refrigeration room 18 Freezer room 19 Compressor DESCRIPTION OF SYMBOLS 20 Evaporator 21 Main condenser 22 Bulkhead 23 Condenser fan 24 Evaporating dish 25 Bottom plate 26 Intake port 27 Outlet port 28 Ventilation passage 30 Evaporator fan 31 Freezer compartment damper 32 Refrigeration compartment damper 33 Duct 34 FCC temperature sensor 35 PCC temperature sensor 36 DFP temperature sensor 37 Dew prevention pipe 38 Dryer 39 Restriction 41 Dew prevention pipe 42 Dryer 43 Restriction 44 Heating heater 50 Evaporator fan 51 Freezer compartment damper 52 Refrigeration compartment damper 53 Duct 54 FCC temperature sensor 55 PCC temperature sensor 56 Compressor 57 Evaporation 60 Compressor 61 Main condenser 62 Dew-proof pipe for freezer 63 Dew-proof pipe for refrigerating room 64 Flow path switching valve 65 Refrigerating restrictor 66 Refrigerating room evaporator 67 Refrigerating room fan 68 Freezing restrictor 69 Freezer room evaporator 70 Freezing Room fan 101 Refrigerator 102 Freezer room 102a Opening part 103 Refrigerated room 103a Opening part 104 Compressor 105 Cooler 106 Cooling fan 107 Freezer room damper 108 Refrigerating room damper 109 Freezer room sensor 110 Cold room sensor 111 Defrost heater 112 Cooler sensor 113 Freezer compartment door 114 Refrigerator compartment door 115 Freezer compartment door sensor 116 Refrigerator compartment door sensor 117 Humidity sensor 118 Control unit

Claims

The housing includes a refrigeration cycle having at least a compressor, an evaporator, and a condenser, and the condenser is a forced air-cooled main condenser, a flow path switching valve connected to the downstream side of the main condenser, A sub-condenser connected to the downstream side of the flow path switching valve, the sub-condenser has a plurality of dew prevention pipes connected in parallel, and a plurality of when the refrigeration cycle is operated under a high load condition A refrigerator characterized by flowing a refrigerant in parallel with a dew-proof pipe.
The refrigerator according to claim 1, wherein when the refrigeration cycle is operated under normal conditions, the number of dew-proof pipes used is smaller than that under high load.
The refrigerator according to any one of claims 1 and 2, wherein an inner diameter of a pipe of the main condenser is 4 mm or more, and an inner diameter of the dewproof pipe is less than 4 mm.
The refrigerator according to any one of claims 1 and 2, wherein a user manually selects a dew-proof pipe to be used when operated under the normal condition.
3. The apparatus according to claim 1, wherein when the refrigeration cycle is operated under a low outside air temperature condition, the air cooling fan of the main condenser is stopped and a plurality of dew prevention pipes are used. Refrigerator.
Refrigeration room, freezing room, refrigeration cycle, evaporator as a component of the refrigeration cycle, evaporator fan for supplying cold air generated in the evaporator to the refrigeration room and the freezing room, and the evaporator A heater for defrosting, a refrigerating room damper for shutting off cool air supplied from the evaporator to the refrigerating room, and a freezer damper for shutting off cool air supplied from the evaporator to the freezing room FC cooling mode in which the freezer compartment damper is opened, the refrigerator compartment damper is closed, and cold air generated in the evaporator is supplied while operating the refrigerating cycle to cool the freezer compartment A PC cooling mode for closing the freezer damper, opening the refrigerator compartment damper, supplying cold air generated in the evaporator while operating the refrigeration cycle, and cooling the refrigerator compartment; An off-cycle cooling mode in which heat is exchanged between the evaporator and air in the refrigerator compartment by closing the freezer damper, opening the refrigerator compartment damper, and operating the evaporator fan while stopping the refrigeration cycle And closing the freezer damper while opening the heater for heating, opening the refrigerator compartment damper, and operating the evaporator fan while stopping the refrigeration cycle, An off-cycle differential mode that melts and removes the attached frost, and the output of the heater for heating is selected based on the amount of food stored in the refrigeration chamber, and then the off-cycle differential mode is performed. Features a refrigerator.
The refrigerator according to claim 6, wherein whether or not the off-cycle differential mode can be performed is determined immediately before the start of the PC cooling mode.
A PCC temperature sensor that detects the temperature of the refrigerator compartment, and a DFP temperature sensor that is installed above the PCC temperature sensor and detects the temperature of the upper portion of the refrigerator compartment. The PCC temperature in the PC cooling mode or the off-cycle cooling mode The refrigerator according to any one of claims 6 and 7, wherein the amount of food stored in the refrigerator compartment is detected based on a difference in temperature change between the sensor and the DFP temperature sensor.
Refrigeration room, freezing room, refrigeration cycle, evaporator as a component of the refrigeration cycle, evaporator fan for supplying cold air generated in the evaporator to the refrigeration room and the freezing room, and the evaporator A refrigeration room damper for blocking cold air supplied from the evaporator to the freezer room, a freezer damper for blocking cold air supplied from the evaporator to the freezer room, an FCC temperature sensor for detecting the temperature of the freezer room, In a refrigerator having a PCC temperature sensor for detecting the temperature of the refrigerator compartment and a DFP temperature sensor that is installed above the PCC temperature sensor and detects the temperature of the upper portion of the refrigerator compartment, the freezer damper is opened, An FC cooling mode for closing the refrigerator compartment damper and supplying cold air generated by the evaporator while operating the refrigeration cycle to cool the refrigerator compartment; and the refrigerator compartment damper Closed, opened the refrigerating room damper, supplied the cool air generated in the evaporator while operating the refrigeration cycle to cool the refrigerating room, closed the freezing room damper, The FCC temperature has an off-cycle cooling mode in which the evaporator and the air in the refrigerator compartment are heat-exchanged by opening the refrigerator compartment damper and operating the evaporator fan while stopping the refrigeration cycle. ON / OFF of the FC cooling mode and the PC cooling mode is determined based on the temperature detected by the sensor or the PCC temperature sensor, and ON / OFF of the off-cycle cooling mode is determined based on the temperature detected by the DFP temperature sensor. The refrigerator characterized by determining.
The refrigerator according to claim 9, wherein when the temperature detected by the FCC temperature sensor or the PCC temperature sensor rises, the FC cooling mode and the PC cooling mode are prioritized over the off-cycle cooling mode. .
The OFF temperature of the DFP temperature sensor that detects the end of the off-cycle cooling mode is set to a temperature that is higher than the ON temperature of the PCC temperature sensor that detects the start of the PC cooling mode. A refrigerator according to claim 1.
A compressor that is a component of a refrigeration cycle, an upper machine room that houses the compressor, and that is disposed in the upper part of the refrigerating room, and a duct that is adjacent to the upper machine room and through which cool air that cools the refrigerating room flows. The refrigerator according to any one of claims 9 and 10, wherein:
Refrigeration room, freezing room, refrigeration cycle, evaporator as a component of the refrigeration cycle, evaporator fan for supplying cold air generated in the evaporator to the refrigeration room and the freezing room, and the evaporator A refrigeration room damper for blocking cold air supplied from the evaporator to the freezer room, a freezer damper for blocking cold air supplied from the evaporator to the freezer room, an FCC temperature sensor for detecting the temperature of the freezer room, In a refrigerator having a PCC temperature sensor for detecting the temperature of the refrigerator compartment and a DFP temperature sensor that is installed above the PCC temperature sensor and detects the temperature of the upper portion of the refrigerator compartment, the freezer damper is opened, An FC cooling mode for closing the refrigerator compartment damper and supplying cold air generated by the evaporator while operating the refrigeration cycle to cool the refrigerator compartment; and the refrigerator compartment damper Closed, opening the refrigerator compartment damper, supplying the cool air generated in the evaporator while operating the refrigeration cycle to cool the refrigerator compartment, and opening the refrigerator compartment damper, Opening the refrigerator compartment damper, supplying the cool air generated by the evaporator while operating the refrigeration cycle, simultaneously cooling the refrigerator compartment and the refrigerator compartment, closing the refrigerator compartment damper, By opening the refrigerator compartment damper and operating the evaporator fan while stopping the refrigeration cycle, it has an off-cycle cooling mode for exchanging heat between the evaporator and the air in the refrigerator compartment, and under normal conditions Cooling by combining FC cooling mode, PC cooling mode, and off-cycle cooling mode, and cooling by combining simultaneous cooling mode and FC cooling mode under overload conditions Refrigerator and wherein the door.
A variable speed compressor is provided. When the compressor is less than a predetermined number of revolutions, the cooling is performed by combining an FC cooling mode, a PC cooling mode, and an off-cycle cooling mode. The refrigerator according to claim 13, wherein cooling is performed by combining cooling modes.
15. The reference temperature of the FCC temperature sensor when switching from the simultaneous cooling mode to the FC cooling mode is set higher than the reference temperature of the FCC temperature sensor when starting the cooling operation. The refrigerator according to one item.
The refrigerator according to any one of claims 13 and 14, wherein a slowing of the cooling rate of the refrigerator compartment is detected from the temperature behavior of the PCC temperature sensor and the DFP temperature sensor, and the defrosting interval of the evaporator is shortened. .
A first storage chamber having an opening on the front surface, a second storage chamber, a refrigeration cycle including a cooler for generating cold air, and the cool air generated by the cooler in the first storage chamber and the A cooling fan that circulates to the second storage chamber, a first damper that selectively allows the cool air from the cooling fan to flow to the first storage chamber, and the cool air from the cooling fan to the second storage chamber. And a defrost heater that defrosts the frost attached to the cooler by heat, and operates the cooling fan when the refrigeration cycle is in a stopped state, the first damper or the second damper An off-cycle cooling mode in which the damper is opened to cool the first storage chamber or the second storage chamber, and a defrosting mode in which frost adhering to the cooler is released by the defrosting heater is provided. From the end of defrost mode in the refrigerator Refrigerator characterized by controlling the interval between times of defrosting mode.
18. The refrigerator according to claim 17, wherein the interval until the next defrosting mode is controlled by the number of off-cycle cooling modes from the end of the defrosting mode.
The refrigerator according to claim 17, wherein an interval until the next defrosting mode is controlled by an integration time of the off-cycle cooling mode from the end of the defrosting mode.
Detecting opening and closing of the first door and the second door, and the opening and closing of the first door and the second door, which respectively open and close the opening of the first storage chamber and the second storage chamber so as to be freely opened and closed. A door opening / closing detection means is provided, and the interval until the next defrosting mode is controlled by the number of times the first door or the second door is opened after the defrosting mode ends. The refrigerator as described in any one of 19.
Detecting opening and closing of the first door and the second door, and the opening and closing of the first door and the second door, which respectively open and close the opening of the first storage chamber and the second storage chamber so as to be freely opened and closed. The door opening / closing detection means is provided, and the interval until the next defrosting mode is controlled by the accumulated opening time of the first door or the second door from the end of the defrosting mode. The refrigerator as described in any one of 1 to 19.
The humidity detection means for detecting the humidity around the refrigerator is provided, and the interval until the next defrosting mode is controlled by the humidity detected by the humidity detection means. Refrigerator.
First temperature adjusting means and second temperature adjusting means for setting the temperature of the first storage chamber and the second storage chamber are provided, and the first temperature adjusting means and the second temperature adjusting means are provided. The refrigerator according to any one of claims 17 to 19, wherein the interval until the next defrosting mode is controlled by the set temperature.