JP2015014373A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator having high energy saving performance by controlling a heating amount by a dew condensation prevention pipe, a high temperature refrigerant inflow amount to an evaporator and an evaporation pressure.SOLUTION: A refrigerator includes: a dew condensation prevention pipe 43 which heats an opening edge of a heat insulating box 10; a first refrigerant flow passage A which flows a refrigerant discharged from a discharge port of a compressor 24 in heat radiation means 41, 42, the dew condensation prevention pipe 43, pressure reducing means 44, an evaporator 7 and a suction port of the compressor 24 in this order; and a second refrigerant flow passage B which flows the refrigerant discharged from the discharge port of the compressor 24 in the heat radiation means 41, 42, the pressure reducing means 44, the evaporator 7 and the suction port of the compressor 24 in this order. Between the heat radiation means 41, 42 and the dew condensation prevention pipe 43, and between the dew condensation prevention pipe 43 and the evaporator 7, refrigerant flow passage control means 110, 100 are provided. The refrigerant flow passage control means 110, 100 perform: switching between the first refrigerant flow passage A and the second refrigerant flow passage B; change of restriction of the pressure reducing means 44; and switching of communicating/blocking of the refrigerant flow passage between the dew condensation prevention pipe 43 and the evaporator 7.

Description

  The present invention relates to a refrigerator.

  As background art in this technical field, there are JP-A-2000-65461 (Patent Document 1) and JP-A-8-189753 (Patent Document 2).

  In the summary column of Patent Document 1, a plurality of storage chambers are formed inside, a compressor, a condenser, a decompressor, and an evaporator are attached to a heat insulation box provided with a heat insulation door, and these are connected in a ring by piping. In a refrigerator that forms a refrigeration cycle and cools the storage room with the cold air generated by the refrigeration cycle, dew condensation prevention embedded in the heat insulating box flange part and the partition flange part by piping between the condenser and the decompressor An electromagnetic three-way valve (refrigerant flow path control means for guiding the high-temperature refrigerant by bypassing this dew-condensation piping to the piping to the dew-condensation piping as well as forming a pipe and guiding the high-temperature refrigerant from the condenser ) Is provided.

  In the summary column of Patent Document 2, a dew-proof pipe provided with a dryer and a capillary tube (decompression unit), a bypass pipe provided with a second dryer and a second capillary tube, and a section of the refrigerator compartment A refrigerator having a temperature sensor that detects temperature, an outside air temperature sensor, and a refrigeration cycle having a switching valve that distributes refrigerant at a dew point temperature determined by the temperature sensor of the temperature sensor of the dew-proof pipe and bypass pipe is described. ing.

JP 2000-65461 A Japanese Patent Laid-Open No. 8-189533

  In the refrigerators described in Patent Documents 1 and 2, a refrigerant flow path for flowing a refrigerant through a dew condensation prevention pipe (dew condensation prevention pipe) and a refrigerant flow path for bypassing the dew condensation prevention pipe are provided. With this configuration, the opening edge of the storage chamber formed in the heat insulating box is heated using the heat radiated from the dew condensation prevention pipe, thereby suppressing the occurrence of dew condensation. However, at the same time, part of the heat enters the storage chamber adjacent to the opening edge and is heated.

  Therefore, the heating of the opening edge by the dew condensation prevention pipe increases the heat in the storage chamber that absorbs heat in the refrigeration cycle, which is one of the factors that cause a decrease in energy saving performance. Therefore, the refrigerant flow path provided with the dew condensation prevention pipe and the refrigerant flow path that bypasses the dew condensation prevention pipe are switched by the refrigerant flow path control means to appropriately control the heating amount by the dew condensation prevention pipe, thereby improving the energy saving performance. Yes.

  On the other hand, in addition to the condensation prevention pipe, heat enters the storage chamber by the refrigerant flowing into the evaporator due to the pressure difference from the heat radiation side when the compressor is stopped, but this phenomenon has not been considered in the past.

  Moreover, in the conventional refrigerator, consideration to evaporation pressure (evaporation temperature) was insufficient. The evaporating pressure is a pressure at which the refrigerant evaporates in the evaporator, and an appropriate evaporating temperature with respect to the temperature of the air that exchanges heat with the refrigerant in the evaporator leads to an improvement in energy saving performance. For example, in a state where the storage chamber is sufficiently cooled, the influence of outside air flowing into the storage chamber increases with the opening and closing of the door. Therefore, it is desirable to control the evaporation pressure according to the air temperature in the storage chamber.

  It is conceivable to control the evaporation pressure by providing a plurality of decompression means and switching between them. The refrigerator described in Patent Document 2 includes two capillary tubes (decompression means), but control of the evaporation pressure by switching the capillary tubes has not been considered. Patent Document 1 does not include a detailed description regarding the decompression means.

  In view of the above, an object of the present invention is to provide a refrigerator with high energy saving performance by controlling the amount of heating by the condensation prevention pipe, the amount of high-temperature refrigerant flowing into the evaporator, and the evaporation pressure.

  In order to solve the above problems, for example, the configuration described in the claims is adopted. The present application includes a plurality of means for solving the above problems. To give an example, a heat insulating box having an opening edge that forms an opening in the front, a door that opens and closes the opening, the door, and the heat insulation. In a refrigerator provided with a storage chamber formed by a box, a compressor, a heat radiating means, a dew condensation preventing pipe for heating the opening edge, a pressure reducing means, and an evaporator, discharge from the discharge port of the compressor The refrigerant to be discharged is discharged from a first refrigerant flow path that flows in the order of the heat dissipating means, the dew condensation prevention pipe, the pressure reducing means, the evaporator, and the suction port of the compressor, and the discharge port of the compressor. A second refrigerant flow path for causing the refrigerant to flow in the order of the heat radiation means, the pressure reduction means, the evaporator, and the suction port of the compressor, and between the heat radiation means and the dew condensation prevention pipe, The refrigerant flow path control means between the prevention piping and the evaporator A refrigerant between the first refrigerant flow path and the second refrigerant flow path, a change in a throttle of the pressure reducing means, and a refrigerant between the dew condensation prevention pipe and the evaporator. It is characterized by switching between communication and blockage of the flow path.

  ADVANTAGE OF THE INVENTION According to this invention, the refrigerator with high energy saving performance can be provided by controlling the heating amount by dew condensation prevention piping, the inflow amount of the high temperature refrigerant | coolant to an evaporator, and evaporation pressure.

It is a front view of the refrigerator regarding Example 1 of this invention. It is AA sectional drawing of FIG. It is a figure explaining the structure of the refrigerating cycle (refrigerant flow path) regarding Example 1 of this invention. It is a schematic diagram at the time of seeing the inside of the machine room regarding Example 1 of this invention from the back. It is a figure which shows the arrangement | positioning position of the wall surface thermal radiation piping and dew condensation prevention piping regarding Example 1 of this invention. It is a cross-sectional enlarged view of the freezer compartment partition wall regarding Example 1 of this invention. It is a cross-sectional schematic diagram which shows the outline of the heat exchange part regarding Example 1 of this invention. It is the figure which showed on the Mollier diagram the state of the refrigerant | coolant in each part of the refrigerating cycle regarding Example 1 of this invention. It is the figure which showed the state of the refrigerant | coolant inside piping from the compressor regarding Example 1 of this invention to a capillary tube. It is the relationship between the time ratio which switches the refrigerant | coolant flow path regarding Example 1 of this invention, and relative humidity. It is a time chart which shows an example of the cooling operation in case the heat load regarding Example 1 of this invention is small. It is a time chart which shows an example of the cooling operation in case the heat load regarding Example 1 of this invention is large. It is the figure which showed on the Mollier diagram the state of the refrigerant | coolant when the evaporation pressure regarding Example 1 of this invention fell. It is a figure explaining the structure of the refrigerating cycle (refrigerant flow path) of the refrigerator regarding Example 2 of this invention. It is a figure explaining the structure of the refrigerating cycle (refrigerant flow path) of the refrigerator regarding Example 3 of this invention. It is the modification 1 of Example 3 of this invention, Comprising: It is a figure explaining the structure of the refrigerating cycle using a four-way valve and a three-way valve. It is the modification 2 of Example 3 of this invention, and is a figure explaining the structure of the refrigerating cycle using a five-way valve. It is the modification 3 of Example 3 of this invention, and is a figure explaining the structure of the refrigerating cycle using a four-way valve and an expansion valve.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Example 1
The refrigerator regarding Example 1 of this invention is demonstrated with reference to FIGS.

  FIG. 1 is a front view of a refrigerator according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line AA of FIG. The refrigerator 1 according to the first embodiment includes a refrigerator room 2, an ice making room 3, an upper freezer room 4, a lower freezer room 5, and a vegetable room 6 as storage rooms from above. The ice making chamber 3 and the upper freezing chamber 4 are arranged on the left and right. The ice making chamber 3, the upper freezing chamber 4, and the lower freezing chamber 5 are collectively referred to as a freezing chamber 60. The refrigerating room 2 is provided with doors 2a and 2b that are separated from each other on the front side, and the ice making room 3, the upper freezing room 4, the lower freezing room 5, and the vegetable room 6 are each a drawer type ice making. The room door 3a, the upper freezer compartment door 4a, the lower freezer compartment door 5a, and the vegetable compartment door 6a are provided.

  The refrigerator 1 includes a door sensor (not shown) that detects the open / closed state, a temperature setting device (not shown) that sets the temperature of the refrigerator compartment 2 and the vegetable compartment 6, and the temperature of the freezer compartment 60, and the like. Yes. A door hinge (not shown) that is fixed to the refrigerator 1 is provided in the upper part of the main body of the refrigerator 1 so that the refrigerator compartment doors 2 a and 2 b can be rotated, and the door hinge is covered with a door hinge cover 39. . Inside the door hinge cover 39, an outside air temperature sensor 37 and an outside air humidity sensor 38 for detecting the temperature and humidity outside the storage room are provided.

  The storage room and the outside of the storage room of the refrigerator 1 are separated by a heat insulating box 10 formed by filling a foam heat insulating material of urethane foam, for example, between the outer box 1a and the inner box 1b. Note that the evaporator storage chamber 8 communicating with the storage chamber is also separated from the outside by a heat insulating box 10. A vacuum heat insulating material 26 is mounted inside the heat insulating box 10 of the refrigerator 1.

  In each storage room of the refrigerator 1, the refrigerator compartment 2 and the freezer compartment 60 are separated by the refrigerator compartment-freezer compartment partition wall 28, and the freezer compartment 60 and the vegetable compartment 6 are separated by the refrigerator compartment-vegetable compartment partition wall 29. It has been. There is no partition that separates the storage chambers of the ice making chamber 3, the upper freezing chamber 4, and the lower freezing chamber 5, but leakage of the air in the freezing chamber 60 from the gaps of the doors 3a, 4a, and 5a to the outside of the storage chamber. A freezer compartment partition wall 30 to prevent is provided. The opening edge of the freezer compartment 60 formed by these partition walls 28, 29 and 30 and the doors 3a, 4a and 5a separate the freezer compartment 60 from the outside of the storage compartment.

  The refrigerator compartment 2 includes a plurality of door pockets 32 provided on the storage compartment side of the doors 2a and 2b and a plurality of shelves 40 that divide the refrigerator compartment 2 into a plurality of storage spaces. In the lower part of the refrigerator compartment 2, there is provided a reduced-pressure storage chamber 20 that enhances the storability of food by reducing the pressure inside.

  The upper freezer compartment 4, the lower freezer compartment 5, and the vegetable compartment 6 are provided with storage containers 4b, 5b, 6b that are pulled out integrally with the doors provided in front of the respective storage compartments. The storage containers 4b, 5b, and 6b can be pulled out by placing the hand on (not shown) and pulling it out to the front side. Similarly, the ice making chamber 3 is provided with a storage container 3b that is pulled out integrally with the ice making chamber door 3a so that the handle (not shown) of the ice making chamber door 3a can be pulled out to the front side.

  The temperatures of the evaporator 7 and each storage room, which will be described later, are as follows: an evaporator temperature sensor 36 provided at the top of the evaporator 7, a refrigerator temperature sensor 33 provided in the refrigerator room 2, and a vegetable room temperature sensor 34 provided in the vegetable room 6. The temperature is detected by a freezer temperature sensor 35 provided in the lower freezer room 5. Furthermore, as described above, the refrigerator 1 also includes the outside air temperature sensor 37 and the outside air humidity sensor 38 that detect the temperature and humidity outside the storage room.

  A control board 31, which is an example of a control device on which a CPU, a memory such as a ROM and a RAM, an interface circuit, and the like are mounted, is disposed on the ceiling wall surface of the refrigerator 1. The control board 31 detects the open / closed state of each door, as described above, for the outside air temperature sensor 37, the outside air humidity sensor 38, the evaporator temperature sensor 35, the refrigerating room temperature sensor 33, the vegetable room temperature sensor 34, the freezer room temperature sensor 35, respectively. It is connected to a door sensor (not shown). The aforementioned CPU controls the ON / OFF of the compressor 24 and the storage chamber fan 9, which will be described later, the rotational speed (the number of revolutions per hour), etc., based on these output values and the programs recorded in the ROM. Control of the three-way valve 110 and the two-way valve 100, control of the respective stepping motors (not shown) for individually opening and closing the refrigerator compartment damper 50, the vegetable compartment damper (not shown), and the freezer compartment damper 52 are performed. Yes.

  The evaporator 7 that cools the air in the refrigerator 1 is provided in an evaporator storage chamber 8 that is formed between the freezer compartment 60 and the back wall of the heat insulating box 10. The air cooled by exchanging heat with the evaporator 7 is sent to the refrigerating room 2 through the refrigerating room duct 11 by the storage room fan 9 provided above the evaporator 7, and the vegetable room duct (not shown). ) To the vegetable compartment 6. Similarly, the air cooled by the evaporator 7 is sent to the storage rooms of the ice making room 3, the upper freezing room 4, and the lower freezing room 5 through the freezing room duct 13. The air blowing to each storage room is controlled by opening and closing the refrigerator compartment damper 50, the vegetable compartment damper (not shown), and the freezer compartment damper 52 in conjunction with the temperature sensors 33, 34, 35 provided in each storage compartment. Yes. The air that has cooled the refrigerator compartment 2, the freezer compartment 60, and the vegetable compartment 6 returns to the evaporator storage compartment 8 via the refrigerator compartment return duct (not shown), the freezer compartment return duct 17, and the vegetable compartment return duct 18, respectively. It is cooled again by the evaporator 7.

  In addition, a defrost heater 22 that heats frost attached to the evaporator 7 during the defrosting operation is installed below the evaporator 7. The defrosted water generated by the defrosting flows into the eaves 23 provided in the lower part of the evaporator storage chamber 8 and then is discharged to the evaporating dish 21 disposed in the machine chamber 19 described later via the drain pipe 27. .

  Next, the configuration of the refrigeration cycle of this example is shown. FIG. 3 is a diagram illustrating the configuration of the refrigeration cycle (refrigerant flow path) of the refrigerator according to the first embodiment. In the refrigerator 1 of the present embodiment, the compressor 24, the heat radiation means 41 that is a heat radiation means for radiating the refrigerant, the wall surface heat radiation pipe 42, and the condensation on the front surfaces of the partition walls 28, 29, and 30, that is, the opening edge. Condensation prevention piping 43 for suppressing, first capillary tube 44a and second capillary tube 44b as decompression means for decompressing the refrigerant, and evaporator for absorbing heat in the storage chamber by exchanging heat between the refrigerant and the air in the storage chamber 7 to cool the storage chamber. In addition, a dryer 45 that removes moisture in the refrigeration cycle, a gas-liquid separator 46 that prevents liquid refrigerant from flowing into the compressor 24, and a refrigerant junction 200 and two ways for controlling the refrigerant flow path are provided. A valve 100 and a three-way valve 110 are also provided, and these are connected by connecting pipes 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, respectively, thereby constituting a refrigeration cycle. doing. In addition, the refrigerator 1 of a present Example uses isobutane as a refrigerant | coolant. In addition, the compressor 24 of this embodiment includes an inverter and can change the rotation speed. However, if the compressor 24 is driven at an excessively low speed, the lubricating oil in the compressor 24 becomes difficult to flow. Has a lower limit.

  In the refrigerator 1 of the present embodiment, the first capillary tube 44a and the second capillary tube 44a and the second capillary tube depressurize the refrigerant by friction generated between the refrigerant and the inner wall of the pipe by passing through a refrigerant channel having a small cross-sectional area as a decompression unit. The capillary tube 44b is provided with two capillary tubes. The first capillary tube 44a and the second capillary tube 44b are collectively referred to as a capillary tube 44. In the first embodiment, both the first capillary tube 44a and the second capillary tube 44b have a diaphragm strength suitable for a case where the load is small. Here, the strength of the throttling indicates the ease of pressure reduction. In the capillary tube 44, the narrower the inner diameter of the tube, the stronger the throttling, and the longer the length, the stronger the throttling.

  The refrigerant junction part 200 is a member that is connected to the three connection pipes 80, 81, and 82 and always connects the three connection pipes 80, 81, and 82 connected to the refrigerant junction part 200.

  The two-way valve 100 is a member capable of switching the opening and closing of the flow path. The state where the front and rear connection pipes 78 and 79 are communicated with each other is an open mode, and the state where the connection pipe 78 and the connection pipe 79 are closed is closed. Mode.

  The three-way valve 110 is a member that includes an inflow port denoted by 110i and two outflow ports denoted by 110o_A and 110o_B, and communicates the inflow port 110i with either one or both of the two outflow ports 110o_A and 110o_B. . In the following, symbol i represents an inlet and symbol o represents an outlet. The state in which the inlet 110i and the outlet 110o_A are in communication with each other is A mode, the state in which the inlet 110i and the outlet 110o_B are in communication with each other is in B mode, and the inlet 110i and both outlets 110o_A and 110o_B are in communication with each other. Let the state which is made to be O mode.

  Here, each component and each connection pipe are arranged as follows. The connection pipe 72 connects the outlet of the compressor 24 and the outdoor radiator 41, the connection pipe 73 connects the external radiator 41 and the wall surface radiation pipe 42, and the connection pipe 74 connects the wall surface radiation pipe 42 and the dryer 45. The connecting pipe 75 connects the dryer 45 and the inlet 110 i of the three-way valve 110. In addition, the three-way valve 110 has an outlet 110o_A connected to the connecting pipe 76 and an outlet 110o_B connected to the connecting pipe 77.

  The other end opposite to the one end connected to the outlet 110 o </ i> _A in the connection pipe 76 is connected to the dew condensation prevention pipe 43. The dew condensation prevention pipe 43 and the two-way valve 100 are connected by the connection pipe 78, the two-way valve 100 and the first capillary tube 44a are connected by the connection pipe 79, and the first capillary tube 44a and the refrigerant are connected by the connection pipe 80. The junction 200 is connected. The other end of the connection pipe 77 connected to the outlet 110o_B of the three-way valve 110 is connected to the second capillary tube 44b. Then, the second capillary tube 44 b and the refrigerant junction 200 are connected by the connection pipe 81.

  The refrigerant junction 200 is connected to the refrigerant pipes 80 and 81 and the refrigerant pipe 82 described above, and is connected to the evaporator 7 through the refrigerant pipe 82. The evaporator 7 and the gas-liquid separator 46 are connected by the refrigerant pipe 83, and the gas-liquid separator 46 and the compressor 24 are connected by the connection pipe 84.

  As will be described in detail later, a heat exchanging portion 47 is provided which is composed of a capillary tube 44 connected to the inlet side of the evaporator 7 and a refrigerant pipe 84 connected to the outlet side of the evaporator 7.

  Next, the 1st refrigerant | coolant flow path A formed by making the inflow port 110i and the outflow port 110o_A of the three-way valve 110 into a communication state (A mode) is demonstrated.

  The refrigerant that has become high-temperature and high-pressure by the compressor 24 flows into the outside-storage-room radiator 41 and the wall surface radiation pipe 42 via the connection pipes 72 and 73 and radiates heat. Thereafter, the refrigerant flows into the three-way valve 110 through the connection pipe 74, the dryer 75, and the connection pipe 75. Since the three-way valve 110 communicates the inflow port 110i and the outflow port 101o_A, the three-way valve 110 flows through the dew condensation prevention pipe 43 via the connection pipe 76 and also radiates heat in the dew condensation prevention pipe 43. Due to the heat radiation from the dew condensation prevention pipe 43, the opening edge (see FIG. 2) of the storage chamber, which is the front surface of the partition walls 28, 29, and 30, is heated. Thereafter, the refrigerant flows into the first capillary tube 44a through the connection pipe 79, the two-way valve 100, and the connection pipe 80.

  The refrigerant is depressurized by the first capillary tube 44a to become a low pressure, and becomes a low pressure because a part of the refrigerant evaporates and the heat of vaporization is taken away. The low-temperature and low-pressure refrigerant absorbs heat from the air in the storage chamber in the evaporator 7 that has flowed in through the refrigerant junction 200 and the connection pipe 82. Due to the heat absorption of the refrigerant, the air in the storage chamber is cooled and the refrigerant further evaporates. The refrigerant that has flowed out of the evaporator 7 returns to the compressor 24 via the connection pipe 83, the gas-liquid separator 46, and the connection pipe 84.

  Next, a description will be given of the second refrigerant flow path B that is formed with the inflow port 110i and the outflow port 110o_B of the three-way valve 110 in a communication state (B mode).

  Similarly to the first refrigerant flow path A, the refrigerant that has become high temperature and high pressure by the compressor 24 dissipates heat in the outdoor radiator 41 and the wall surface heat radiation pipe 42 through the connection pipes 72, 73, 74, and 75. Flows into valve 110. Since the three-way valve 110 communicates the inflow port 110i and the outflow port 110o_B, the refrigerant flows to the second capillary tube 44b through the connection pipe 77. Thereafter, as in the first refrigerant flow path A, the refrigerant returns to the compressor 24 while flowing into the evaporator 7 and the gas-liquid separator 46 via the connection pipes 81, 82, 83, and 84.

  Next, the installation location of each member constituting the refrigeration cycle shown in FIG. 3 will be described.

  FIG. 4 is a schematic diagram when the inside of the machine room is viewed from the back. As shown in FIG. 2, the refrigerator 1 includes a machine room 19 on the outside of the heat insulating box 10, below the back of the vegetable room 6 of the refrigerator 1 and below the evaporator storage room 8. Machine room openings 19 a and 19 b are formed on the wall surface of the refrigerator 1 constituting both sides of the machine room 19, and outside air is transferred from the machine room opening 19 a to the machine room by a fan 41 outside the storage room provided in the machine room 19. It has a structure that can flow into 19 and flow out from the machine room opening 19b. In the machine room 19, there are a machine room opening 19a, a storage room radiator 41, a storage room fan 41a, a compressor 24, a three-way valve 110, a two-way valve 100, and a machine room opening 19b in order from the right in the drawing. It is arranged. The dryer 45 is disposed at the upper position of the two-way valve 100 and the three-way valve 110, and the evaporating dish 21 is disposed above the compressor 24 and below the drain pipe 27.

  During the cooling operation, the compressor 24 and the outdoor storage room radiator 41 that are at a high temperature drive the external storage room fan 41a to exchange heat with the outside air taken in from the machine room opening 19a to radiate heat. Therefore, the heat radiation amount of the compressor 24 and the outdoor storage room radiator 41 can be adjusted by changing the rotational speed of the external storage room fan 41a and the ON / OFF of the external storage room fan 41a. Since the air heated by the heat radiation from the compressor 24 and the heat radiator 41 outside the storage room is pressurized by the fan 41a outside the storage room, it is discharged from the machine room opening 19b to the outside of the machine room 19 having a relatively low pressure. The Further, drain water generated at the time of defrosting is discharged from the drain pipe 27 to the evaporating dish 21 and evaporated by heat from the compressor 24 and the outdoor radiator 41.

  FIG. 5 is a diagram showing the arrangement positions of the wall surface heat radiation pipe 42 and the dew condensation prevention pipe 43. As shown in FIG. 3, the wall surface heat radiation pipe 42 and the dew condensation prevention pipe 43 are members through which a high-temperature and high-pressure refrigerant flows.

  The wall surface heat radiation pipe 42 is disposed between the outer box 1a and the inner box 1b of the refrigerator 1 (see FIG. 2) so as to be in contact with the outer surface of the outer box 1a. The outer box 1a is made of a steel plate, and the high-temperature refrigerant in the wall surface heat radiation pipe 42 radiates heat to the air outside the storage chamber via the outer surface of the outer box 1a. In addition, the dew condensation prevention pipe 43 is disposed in front of the refrigerator compartment / freezer compartment partition wall 28, the freezer compartment / vegetable compartment partition wall 29, and the compartment compartment wall 30 of the freezer compartment (part indicated by a one-dot chain line in FIG. 5). As shown in FIGS. 1 and 2, the front portions of the partition walls 28, 29, and 30 form the opening edges of the ice making chamber 3, the upper freezing chamber 4, and the lower freezing chamber 5.

  Next, details of the vicinity of the dew condensation prevention pipe 43 will be described using the freezer compartment partition wall 30 as a representative.

  FIG. 6 is an enlarged cross-sectional view of the freezer compartment partition wall 30. Inside the freezer compartment partition wall 30, a dew condensation prevention pipe 43 through which the refrigerant that has become high temperature and high pressure in the compressor 24 flows is provided. The dew condensation prevention pipe 43 is provided in the vicinity of the partition cover 30 a provided on the front surface portion of the freezer compartment partition wall 30. In addition, although the partition cover 30a of the refrigerator 1 in connection with a present Example is a product made from a steel plate, it is not limited to this, What is necessary is just to comprise with materials, such as a metal with high heat conductivity. Since the freezer compartment partition wall 30 is adjacent to the freezer compartment 60 that keeps the room in a freezing temperature zone (for example, about −18 ° C.), when the heating means is not provided, the freezer compartment partition wall 30 is a freezer compartment. It is cooled by 60 low-temperature air and becomes cooler than the outside air around the refrigerator 1. Therefore, if the outside air around the refrigerator 1 is highly humid, the surface temperature of the partition cover 30a is likely to be lower than the dew point temperature, and condensation may occur on the surface of the partition cover 30a due to moisture in the air near the partition cover 30a. is there. On the other hand, as shown in FIG. 3, by providing a condensation prevention piping 43 in the vicinity of the partition cover 30a through which the high-temperature refrigerant before being depressurized by the capillary tube 44 flows, the heat flow 91 in FIG. The partition cover 30a is heated with a refrigerant to suppress condensation generated on the partition cover 30a.

  The front portions of the freezer compartment-freezer compartment partition wall 28 and the freezer compartment-vegetable compartment partition wall 29 are members that form the opening edge of the freezer compartment 60 in the same manner as the freezer compartment partition wall 30 and are shown in FIG. A dew condensation prevention pipe 43 is provided in the vicinity of a partition cover (not shown) provided on the front surface of each partition wall 28, 29 with the same configuration as the freezer compartment partition wall 30. Heating.

  FIG. 7 is a schematic cross-sectional view showing an outline of the heat exchanging portion 47 of the refrigerator. The refrigerator 1 of the present embodiment is provided with a heat exchanging portion 47 in which a first capillary tube 44 a and a second capillary tube 44 b are disposed in the vicinity of the refrigerant pipe 84. The first capillary tube 44a and the second capillary tube 44b are provided on opposite sides of the refrigerant pipe 84, respectively. The heat exchanging portion 47 is formed inside the heat insulating box 10. Low temperature refrigerant flows into the refrigerant pipe 84 connected to the outlet side of the evaporator 7, while high temperature refrigerant from the heat radiating side flows into the capillary tube 44. Therefore, when the refrigerant flows through the first capillary tube 44a, a heat flow 93a is generated from the first capillary tube 44a toward the refrigerant pipe 84 to perform heat exchange. Similarly, when the refrigerant flows through the second capillary tube 44b, a heat flow 93b is generated from the second capillary tube 44b toward the refrigerant pipe 84.

  Next, the action of the heat exchanging portion 47 and the state change of the refrigerant on the heat radiation side from the compressor 24 to the capillary tube 44 will be described with reference to FIGS.

  FIG. 8 is a diagram showing the state of the refrigerant in each part of the refrigeration cycle on the Mollier diagram. FIG. 9 is a view showing the state of the refrigerant in the piping from the compressor 24 to the capillary tube 44. 8 and 9 show the case where the refrigerant circulates on the first refrigerant flow path A side.

  In FIG. 8, the vertical axis represents the refrigerant pressure, and the horizontal axis represents the specific enthalpy of the refrigerant. The refrigerant states B to E, H, and I shown in FIGS. 8 and 9 represent the same state in FIGS. 8 and 9.

  Since the refrigerant in the state A flowing into the compressor 24 is compressed by the compressor 24, the specific enthalpy of the refrigerant increases from h1 to h2, and the pressure increases from P1 to P2 (states A to B). The refrigerant (state B) that has been compressed to high temperature and high pressure is in the order of the outdoor radiator 41 (state B to C), the wall surface radiator 42 (state C to D), and the dew condensation prevention pipe 43 (state D to E). As a result of heat dissipation, the specific enthalpy of the refrigerant decreases from h2 to h3. The refrigerant that has reached the state E exchanges heat with the refrigerant in the connection pipe 84 in the heat exchange section 47 while being depressurized when passing through the first capillary tube 44a, so that the specific enthalpy decreases from h3 to h4, The refrigerant pressure decreases from P2 to P1 (states E to F). Thereafter, the refrigerant (state F) at the inlet of the evaporator 7 absorbs heat by exchanging heat with the air in the storage chamber, and the specific enthalpy of the refrigerant increases from h4 to h5 (states F to G). The refrigerant (state G) at the outlet of the evaporator 7 returns to the compressor 24 again after the specific enthalpy of the refrigerant increases from h5 to h1 due to the heat moving from the first capillary tube 44a in the heat exchange unit 47 ( State G to A). During the circulation of the state A-B-C-D-E-F-G shown on the Mollier diagram, the refrigerant is roughly divided into three states: a gas phase region, a gas-liquid two-phase region, and a liquid phase region. Change.

  Here, the state of the refrigerant from the outlet (B) of the compressor 24 on the heat radiation side of the refrigeration cycle to the inlet (E) of the first capillary tube 44a will be considered with reference to FIG. The point where the gas phase changes from the gas-liquid two-phase region is H, the point where the gas-liquid two-phase region changes from the liquid-phase region is I, the gas refrigerant is 94, the liquid refrigerant is 95, and the gas refrigerant 94 only. The gas phase region is represented by the section BH, the gas-liquid two-phase region where the gas refrigerant 94 and the liquid refrigerant 95 are mixed is represented by the section HI, and the liquid phase region of the liquid refrigerant 95 alone is represented by the section IE.

  In FIG. 9, the refrigerant flows from symbol B to E, and the gas refrigerant 94 compressed to the high temperature and high pressure by the compressor 24 is stored in the order of the outdoor heat radiator 41, the wall surface heat radiation pipe 42, and the dew condensation prevention pipe 43. Heat is radiated to the outside, and the state of the refrigerant changes in the order of the gas phase region (section BH), the gas-liquid two-phase region (section HI), and the liquid phase region (section IE). In the refrigerator 1 of the present embodiment, the gas-phase region reaches the gas-liquid two-phase region in the middle of the outdoor storage radiator 41, and reaches the liquid-phase region in the middle of the dew condensation prevention pipe 43. Therefore, the proportion of the gas refrigerant 94 is large in the outdoor radiator 41 and the proportion of the liquid refrigerant 95 is large in the dew condensation prevention pipe 43. The liquid refrigerant 95 has a higher density than the gas refrigerant 94. For example, in isobutane, the density ratio of the gas refrigerant 94 and the liquid refrigerant 95 is about 1:50 at a condensation temperature of 30 ° C. Therefore, since the ratio of the liquid refrigerant 95 is large in the dew condensation prevention pipe 43, the amount of refrigerant contained in the dew condensation prevention pipe 43 is larger than the pipe internal volume.

  Next, the operation of the heat exchange unit 47 shown in FIGS. 3 and 7 will be described with reference to FIG. The specific enthalpy of the refrigerant (state F) at the inlet of the evaporator 7 is decreased from h3 to h4 by the heat exchanging unit 47, and the heat absorption amount (h5-h4) in the evaporator 7 is increased. Since the cooling efficiency (= endothermic amount (h5−h4) / consumed energy (h2−h1)) is improved by increasing the endothermic amount in the evaporator 7, the refrigerator 1 of the present embodiment is provided with a heat exchanging portion 47. Energy saving performance.

  The main configuration of the refrigerator 1 according to the present embodiment has been described above. Next, the control method of the three-way valve 110 and the two-way valve 100 in the refrigerator 1 of the present embodiment will be described.

  FIG. 10 is a relationship between the time ratio of the first refrigerant flow path A and the second refrigerant flow path B of the refrigerator and the relative humidity related to Example 1. In the refrigerator 1 of the present embodiment, the first refrigerant flow path A and the second refrigerant flow path B are switched according to the temperature and humidity around the refrigerator 1 obtained by the outside air temperature sensor 37 and the outside air humidity sensor 38 described above. Yes. The horizontal axis of FIG. 10 is the relative humidity, and the vertical axis is the heating rate of the dew condensation prevention pipe 43, that is, the rate of time for fixing the refrigerant channel to the first refrigerant channel A side. For example, in the case of RH2 where the relative humidity is high, the ratio of the time (tA2) in which the three-way valve 110 is set to the A mode and the refrigerant flows through the condensation prevention pipe 43 is increased, and the ratio of the time in which the condensation prevention pipe 43 is bypassed in the B mode. (TB2) is shortened. On the other hand, in the case of RH1 where the relative humidity is low, the three-way valve 110 is set to the A mode to shorten the ratio (tA1) of flowing the refrigerant through the condensation prevention piping 43, and the three-way valve 110 is set to the B mode to bypass the condensation prevention piping 43. The proportion of time (tB1) to be used is increased. In the actual cooling operation, the first refrigerant channel A side, the second refrigerant channel so as to suppress the occurrence of condensation on the partition walls 28, 29, and 30 according to the temperature and humidity conditions around the refrigerator 1. A switching time on the B side is determined in advance, and when the compressor 24 is ON, the three-way valve 110 is switched between the A mode and the B mode according to the predetermined switching time. For example, in the refrigerator 1 according to this embodiment, when the outside air is 30 ° C. and the relative humidity is 50%, the A mode is switched for 10 minutes and the B mode is switched for 20 minutes. When the outside air is 30 ° C. and the relative humidity is 70%, there is a high possibility that condensation occurs. Therefore, the partition walls 28, 29, and 30 are heated for 20 minutes in the A mode, and the B mode is set to 10 minutes.

  FIG. 11 a is a time chart showing an example of the cooling operation of the refrigerator 1 related to Example 1 when the heat load is small.

  When the heat load is small, the refrigeration operation for cooling the refrigerator compartment 2, the refrigeration operation for cooling the freezer compartment 60, and the operation pattern of OFF in which the compressor 24 is stopped are basically used. Repeat these operations unless done. Specifically, when the freezer compartment temperature obtained from the freezer compartment temperature sensor 34 rises to TF1 while the compressor 24 is stopped, the compressor 24 is turned on and the refrigeration operation is performed. When the temperature of the refrigerator compartment decreases and the refrigerator compartment temperature obtained from the refrigerator compartment temperature sensor 33 reaches TR2, the refrigerator operation is terminated, and the refrigerator operation is continued until the freezer compartment temperature reaches TF2. When the temperature of the refrigerator compartment rises during the freezing operation and exceeds the temperature TR1, the refrigerator compartment 2 and the freezer compartment 60 are cooled at the same time in the refrigerator / freezer operation. Further, the rotational speed of the compressor 24 is set lower than that in FIG.

  Control of the two-way valve 100 and the three-way valve 110 at this time will be described. As shown in FIG. 10, when the compressor 24 is in operation, the switching time between the A mode and the B mode of the three-way valve 110 is determined in advance according to the temperature and humidity, and the three-way valve 110 is switched accordingly. When the three-way valve 110 is set to the A mode so that the refrigerant flows through the first refrigerant flow path A, the two-way valve 100 is set to the open mode and the three-way valve 110 is set to the B mode to set the second refrigerant flow. When the refrigerant flows in the path B, the two-way valve 100 is set to the closed mode.

  The three-way valve 110 is set to the A mode before the compressor 24 stops, and the refrigerant flows through the first refrigerant flow path A until the compressor 24 stops. When the compressor 24 is stopped, the three-way valve 110 remains in the A mode, but the two-way valve 100 is set to the closed mode after the compressor 24 is stopped. Further, when the freezer temperature becomes TF1 and the compressor 24 is operated again, the two-way valve 100 is set in the open mode so that the refrigerant can circulate while the three-way valve 110 is fixed in the A mode, and thereafter The compressor 24 is driven.

  Next, FIG. 11b is a time chart showing an example of the cooling operation of the refrigerator related to Example 1 when the heat load is large.

  Assuming that the heat load is large, assume that the power is first turned on when the refrigerator 1 is installed. The temperature in the storage chamber is cooled from a temperature equal to the outside air temperature TO. The refrigerator compartment 2 and the freezer compartment 60 are cooled at the same time, and the rotational speed of the compressor 24 is higher than that in FIG. The two-way valve 100 is operated in the open mode in which the front and rear connection pipes 78 and 79 are communicated, and the three-way valve 110 is operated in the O mode in which the inflow port 110i and both the outflow ports 110o_A and 110o_B are in communication. After the refrigerator compartment temperature reaches TR2, the freezer compartment 60 is cooled alone. Thereafter, when the freezer compartment temperature reaches TF1, it is determined that the refrigerator compartment temperature is TR1 or less, the freezer compartment temperature is TF1 or less, and the thermal load in the storage compartment is reduced, and the A mode and B mode are the same as in FIG. 11a. Moves to the operation of switching.

  The main configuration and control of the refrigerator 1 according to the present embodiment has been described above. Next, the effect which the refrigerator 1 of a present Example show | plays is demonstrated.

  The refrigerator 1 according to the present embodiment includes a first refrigerant flow path A through which the refrigerant flows in the dew condensation prevention pipe 43 and a second refrigerant flow path B that bypasses the dew condensation prevention pipe 43. The valve 110 can be switched. Thereby, the heating amount of the partition walls 28, 29 and 30 by the dew condensation prevention pipe 43 is controlled, and the energy saving performance can be improved while suppressing the occurrence of dew condensation. The reason for this will be described with reference to FIGS.

  As shown in FIG. 6, in the refrigerator 1 of the present embodiment, the front portion of the freezer compartment partition wall 30 is heated by the heat flow 91 by the high-temperature refrigerant flowing through the dew condensation prevention pipe 43, thereby opening the opening edge of the storage room Condensation is prevented. However, part of the heat radiated from the dew condensation prevention pipe 43 (heat flow 92) enters the freezer compartment 60 adjacent to the freezer compartment partition wall 30 and heats the storage compartment. In order to maintain the storage chamber at a predetermined temperature, in addition to the heat entering from the outside of the refrigerator storage chamber, the heat entering the storage chamber from the dew condensation prevention pipe 43 needs to be absorbed by the refrigeration cycle. That is, the heating of the front surface portion of the freezer compartment partition wall 30 by the dew condensation prevention pipe 43 increases the heat load in the storage chamber, which causes a reduction in energy saving performance. Although the description has been given by using the freezer compartment partition wall 30, the same phenomenon occurs when the partition walls 28 and 29 are heated by the dew condensation prevention pipe 43.

  Therefore, the refrigerator 1 of the present embodiment includes the first refrigerant flow path A through which the refrigerant flows in the dew condensation prevention pipe 43 and the second refrigerant flow path B that bypasses the dew condensation prevention pipe 43, and the temperature around the refrigerator 1. The first refrigerant channel A and the second refrigerant channel B are switched according to the humidity. Specifically, as shown in FIG. 10, at the time of high humidity where condensation easily occurs on the front surface of the freezer compartment partition wall 30, the ratio (tA2) of setting the three-way valve 110 to the A mode is increased and the B mode is set. By reducing the time ratio (tB2) to be performed, the heating amount of the dew condensation prevention pipe 43 is increased to prevent dew condensation. On the other hand, at the time of low humidity where condensation is unlikely to occur, the amount of heating in the storage chamber by the condensation prevention piping 43 is reduced by decreasing the A mode time ratio (tA1) and increasing the B mode time ratio (tA2). ing. Thus, in the refrigerator 1 of the present embodiment, the amount of heating by the dew condensation prevention pipe 43 can be adjusted according to the humidity, so that excessive heating in the storage chamber by the dew condensation prevention pipe 43 is suppressed while preventing condensation. be able to.

  As described above, the heating amount by the dew condensation prevention pipe 43 is appropriately switched between the first refrigerant flow path A through which the refrigerant flows in the dew condensation prevention pipe 43 and the second refrigerant flow path B that bypasses the dew condensation prevention pipe 43. It is possible to improve the energy saving performance while preventing condensation.

  Further, in the refrigerator 1 of the present embodiment, in addition to providing the three-way valve 110 between the wall surface heat radiation pipe 42 and the dew condensation prevention pipe 43, between the dew condensation prevention pipe 43 and the first capillary tube 44a, two A direction valve 100 is provided. Thereby, inflow of the high temperature refrigerant | coolant to an evaporator can be suppressed and energy saving performance can be improved. The reason for this will be described with reference to FIGS. 3, 8 and 11a.

  When the heat load is small, in the refrigerator 1 of the present embodiment, in addition to operating the compressor 24 at a low speed, the compressor 24 is stopped to stop cooling the storage chamber so that the storage chamber is not overcooled. Thus, the storage room is maintained at a predetermined temperature (for example, 4 ° C. in the refrigerator room).

  On the other hand, in a refrigerator that does not include a refrigerant flow path control unit, the following problems occur when the compressor 24 is stopped. When the compressor 24 is driven, as shown in FIG. 8, the refrigerant pressure P <b> 2 in the heat release side of the refrigeration cycle, i.e., the outdoor storage room heat sink 41, the wall surface heat radiation pipe 42, and the dew condensation prevention pipe 43 is evaporated. It is higher than the pressure P1 of the refrigerant in the vessel 7. On the other hand, when the compressor 24 is stopped, the refrigerant in the refrigerant pipe on the heat radiation side evaporates so as to eliminate the pressure difference between the refrigerant in the refrigerant pipe on the heat radiation side and the refrigerant in the evaporator 7. May flow into the vessel 7. When a high-temperature refrigerant on the heat radiation side flows into the evaporator 7 installed in the storage chamber of the refrigerator 1, the storage chamber is heated, so that the heat load in the storage chamber increases, and the heat is generated in the next cooling operation. It is necessary to absorb heat. For this reason, when the compressor 24 is stopped, there is a problem that the high-temperature refrigerant on the heat radiation side flows into the evaporator 7 to increase the heat load and the energy saving performance is lowered.

  Therefore, in the refrigerator 1 of the present embodiment, as shown in FIG. 11 a, when the compressor 24 is stopped, the three-way valve 110 is set to the A mode and the two-way valve 100 is set to the closed mode, whereby the dew condensation prevention pipe 43 and the evaporator are set. The refrigerant | coolant flow path between 7 is obstruct | occluded (refer FIG. 3). Thereby, since the high temperature refrigerant | coolant which exists from the compressor 24 to the dew condensation prevention piping 43 does not flow into the evaporator 7, energy saving performance can be improved.

  In addition, the three-way valve 110 provided in the refrigerator 1 of the present embodiment includes an inflow port 110i and an inflow port 110i in addition to the A mode and the B mode in which any of the outflow ports 110o_A and 110o_B communicates. An O mode is provided in which both the outlets 110o_A and 110o_B communicate with each other. When the three-way valve 110 is set to the O mode, the refrigerant can flow through both of the two capillary tubes 44a and 44b. Thereby, evaporation pressure can be controlled and energy saving performance can be improved. The reason for this will be described with reference to FIGS. 11a, 11b, and 12. FIG.

  First, the relationship between the evaporation pressure and energy saving performance will be described.

  In FIG. 12, the state when the evaporation pressure is lower than the refrigeration cycle (dotted line) shown in FIG. 8 is indicated by a solid line on the Mollier diagram. When the evaporation pressure P1 decreases to P1 ', the difference between the condensation pressure P2 and the evaporation pressure P1' becomes larger than the difference between P2 and P1 before the evaporation pressure decreases. Therefore, the energy consumed by the compressor 24 increases from (h2−h1) to (h2′−h1). Therefore, when the heat load is large (see FIG. 11b), the difference between P2 and P1 is reduced by weakening the throttle of the refrigeration cycle, and the operation with high energy saving performance is performed.

  On the other hand, a cooling operation in which the evaporation temperature is lowered (evaporation pressure is lowered) may be necessary. For example, when the heat load is small and the storage chamber is sufficiently low as shown in FIG. 11a, it is necessary to lower the evaporation temperature in accordance with the decrease in the storage chamber temperature. As means for lowering the evaporation temperature (evaporation pressure), it is conceivable to increase the decompression amount of the refrigerant by increasing the throttle and to increase the rotational speed of the compressor 24. If the value is lowered, the compressor 24 can be driven at a low speed and the energy consumption of the compressor 24 can be reduced, so that the operation with high energy saving performance can be performed.

  From the above, it can be seen that controlling the evaporation pressure by changing the squeezing strength of the refrigeration cycle in accordance with the heat load leads to an improvement in energy saving performance.

  In the refrigerator 1 according to the present embodiment, the first capillary tube 44a and the first capillary tube 44b have a throttle strength suitable for conditions with a small heat load, as compared with a case where the heat load described later is large. It is strong. As a result, when the heat load is small, the refrigerant can be flowed through any one of the capillary tubes 44 to obtain an appropriate throttle strength, and a cooling operation with high energy saving performance can be performed.

  Further, in the refrigerator 1 of the present embodiment, as shown in FIG. 11b, when the heat load is large, the three-way valve 110 is set to the O mode so that both the first capillary tube 44a and the second capillary tube 44b are provided. A refrigerant is allowed to flow. In both the first capillary tube 44a and the second capillary tube 44b, the refrigerant is depressurized by passing through the refrigerant flow path having a small cross-sectional area. Therefore, if the refrigerant flows through both capillary tubes, the cross-sectional area of the refrigerant flow path Increases and the amount of decompression decreases. Therefore, when the heat load is large, the three-way valve 110 is set to the O mode, the refrigerant is made to flow simultaneously through the first capillary tube 44a and the second capillary tube 44b, the throttle is weakened, the evaporation temperature is increased, Perform cooling operation with high energy-saving performance.

  As described above, the decompression means is constituted by a plurality of capillary tubes 44, and the refrigerant flow control means causes the refrigerant to flow into any one of the plurality of capillary tubes 44 and the plurality of capillary tubes. The diaphragm is changed by switching between the case where the refrigerant is supplied to 44. That is, the three-way valve 110 includes an A mode and a B mode in which the refrigerant flows in either the first refrigerant flow path A or the second refrigerant flow path B, and an O mode in which both the refrigerant flows simultaneously. It is possible to improve the energy saving performance by controlling the evaporation pressure according to the above.

  In addition, in the refrigerator 1 of a present Example provided with the inverter in the compressor 24, it is effective for the improvement of energy saving performance further. As shown in FIG. 11b, when the heat load is large, the rotation speed of the compressor 24 is increased so that the storage chamber can be quickly cooled. In this case, the evaporation pressure of the refrigerant is reduced. That is, energy saving performance will fall. On the other hand, in the refrigerator 1 of the present embodiment, it is possible to suppress a decrease in the evaporation pressure by weakening the throttle. On the other hand, when the heat load is small as shown in FIG. 11a, the rotational speed of the compressor 24 is set to a low speed from the viewpoint of energy saving performance. It may become impossible to absorb heat. Therefore, in this embodiment, the diaphragm is strengthened to reduce the evaporation pressure, so that the heat in the refrigerator can be absorbed even when the compressor 24 is at a low speed.

  As described above, in the present embodiment, the heat insulation box 10 having the opening edge that forms the opening in the front, and the doors (2a, 2b, 3a, 4a, 5a, 6a) that can open and close the opening. And a storage chamber (2, 3, 4, 5, 6) formed by the door and the heat insulating box 10, the compressor 24, the heat radiating means 41, 42, and a dew condensation preventing pipe 43 for heating the opening edge, In the refrigerator 1 including the decompression means 44 and the evaporator 7, the refrigerant discharged from the discharge port of the compressor 24 is radiated from the heat radiation means 41 and 42, the dew condensation prevention pipe 43, the decompression means 44, the evaporator 7, and the compressor. The refrigerant discharged from the first refrigerant flow path A flowing in the order of the 24 suction ports and the discharge port of the compressor 24 is supplied to the heat radiation means 41, 42, the decompression means 44, the evaporator 7, and the suction port of the compressor 24. A second refrigerant flow path B that flows in sequence, and the heat dissipating means 41 and 42 and the dew condensation prevention pipe 4. And between the dew condensation prevention pipe 43 and the evaporator 7, the refrigerant flow control means 110, 100 are provided, and the first refrigerant flow path A and the second refrigerant are provided by the refrigerant flow control means 110, 100. The switching of the flow path B, the change of the throttle of the decompression means 44, and the switching of the communication and blocking of the refrigerant flow path between the dew condensation prevention pipe 43 and the evaporator 7 are performed.

  In other words, the anti-condensation pipe 43, its bypass flow path, and two capillary tubes are provided. Further, the refrigerant flow path is controlled by the three-way valve 110 and the two-way valve 100 to control the heating amount by the dew condensation prevention pipe 43 and evaporation. A refrigerator with high energy saving performance can be obtained by suppressing the inflow of the high-temperature refrigerant into the container 7 and controlling the evaporation pressure.

  In addition to the above effects, the refrigerator 1 of the present embodiment has been devised so as to obtain various effects, which will be described below.

  As described above, in a refrigerator that does not include a refrigerant flow path control unit, when the compressor 24 is stopped, the high-temperature refrigerant on the heat radiation side flows into the evaporator 7 and the energy saving performance may be reduced. Similarly, even when the three-way valve 110 is set to the B mode, the high-temperature refrigerant in the dew condensation prevention pipe 43 downstream from the three-way valve 110 (see FIG. 3) flows into the evaporator 7 to reduce the energy saving performance. Sometimes. As shown in FIG. 9, since the refrigerant in the dew condensation prevention pipe 43 has a high proportion of the liquid refrigerant 95 having a high density, the refrigerant amount in the dew condensation prevention pipe 43 is larger than the pipe internal volume. Therefore, even the refrigerant staying in the dew condensation prevention pipe 43 has a great influence on the energy saving performance due to the increase in the heat load when it flows into the evaporator 7. Therefore, in the refrigerator 1 of the present embodiment, when the three-way valve 110 is in the B mode, the two-way valve 100 is set in the closed mode so that the high-temperature refrigerant in the dew condensation prevention pipe 43 does not flow into the evaporator 7, so that energy saving performance is achieved. It is improving.

  Next, the effect of the heat exchange unit 47 will be described. As shown in FIG. 3, in the refrigerator 1 of the present embodiment, heat exchange is performed between the capillary tube 44 and the connection pipe 84 in the heat exchange unit 47. As shown in FIG. 8, when the refrigerant flows through the capillary tube 44, the specific enthalpy of the refrigerant is decreased from h3 to h4, and the heat absorption amount (h5-h4) by the refrigerant is increased, so that the cooling efficiency (= the heat absorption amount (= h5-h4) / energy consumption (h2-h1)). That is, the energy saving performance is improved by exchanging heat between the capillary tube 44 and the connection pipe 84.

  As shown in FIG. 7, the first capillary tube 44a and the second capillary tube 44b are provided so as to sandwich the refrigerant pipe 84 therebetween. For example, when the first capillary tube 44a and the second capillary tube 44b are provided close to each other and the refrigerant is allowed to flow only through the first capillary tube 44a, the refrigerant flowing in the first capillary tube 44a is transferred to the connection pipe 84. In addition, heat exchange is performed with the second capillary tube 44b in which no refrigerant flows. Since the upstream side of the second capillary tube 44b is closed by the three-way valve 110 and the downstream side is connected to the evaporator 7 (see FIG. 3), when the second capillary tube 44b is heated, the heat causes the evaporator 7 will also be heated. The refrigerant in the first capillary tube 44a exchanges heat with the second capillary tube 44b, so that the amount of heat exchanged with the connection pipe 84 decreases. Therefore, in the refrigerator 1 of the present embodiment, the first capillary tube 44a and the second capillary tube 44b are provided apart from each other, thereby suppressing heat exchange between the capillary tubes 44 and improving the energy saving performance by the heat exchange unit 47. The effect is enhanced.

  Next, the reason why the three-way valve 110 is set to the A mode and the effect thereof before the stop of the compressor 24 shown in FIG.

  Since the refrigerant does not circulate while the compressor 24 is stopped, the front surfaces of the partition walls 28, 29, and 30 cannot be heated by the dew condensation prevention pipe 43. Therefore, the temperature of the front part of the partition walls 28, 29, and 30 is lowered, and condensation easily occurs on the front part of the partition walls 28, 29, and 30. Therefore, the three-way valve 110 is operated in the A mode before the compressor 24 is stopped, and the compressor 24 is stopped in a state where the temperature of the front portion of the partition walls 28, 29, and 30 is high. Even if the temperature drops, a relatively high temperature can be maintained. When the compressor 24 is stopped, the two-way valve 100 is in the closed mode while the three-way valve 110 is in the A mode. As a result, the refrigerant flow path downstream of the dew condensation prevention pipe 43 is blocked (see FIG. 3), so that the high temperature refrigerant remains in the dew condensation prevention pipe 43 even when the compressor 24 is stopped. Furthermore, although the refrigerant in the dew condensation prevention pipe 43 is cooled by the adjacent freezer compartment 60 and the temperature is likely to decrease, the pressure also decreases as the temperature decreases, so that the high temperature refrigerant upstream of the three-way valve 111 due to the pressure difference. Flows into the condensation prevention pipe 43. Therefore, a relatively high-temperature refrigerant is easily maintained in the dew condensation prevention pipe 43, so that a decrease in temperature at the front portions of the partition walls 28, 29, and 30 can be suppressed. Further, after restarting the operation of the compressor 24, the refrigerant is circulated through the three-way valve 110 in the A mode, and the refrigerant is caused to flow through the dew condensation prevention pipe 43, thereby quickly heating the front portions of the partition walls 28, 29, and 30. The temperature is not lowered.

  Furthermore, in the refrigerator 1 of the present embodiment, consideration is also given to the installation location of the two-way valve 100. As shown in FIG. 3, in the refrigerator 1 of the present embodiment, the two-way valve 100 is provided in the refrigerant flow path between the dew condensation prevention pipe 43 and the first capillary tube 44a. Even if the two-way valve 100 is provided in the connection pipe 80 downstream of the tube 44a, the same effect as described above can be obtained.

  On the other hand, since the refrigerant that has passed through the first capillary tube 44a has a low temperature and a low pressure, the two-way valve 100 into which the refrigerant flows also has a low temperature. If the two-way valve 100 is provided in the high-temperature machine room 19, the refrigerator room 2, or the vegetable room 6, condensation may occur in the two-way valve 100 that has become low temperature. Necessary. Furthermore, if the two-way valve 100 is provided in the machine room 19, heat exchange is performed between the low-temperature refrigerant and the air in the machine room 19, and the air outside the storage room is absorbed by the refrigeration cycle. This also leads to a decline.

  On the other hand, when it is arranged around the low temperature freezer compartment 60 or the evaporator 7, a two-way valve that operates normally even when the surroundings are at a low temperature is required, so that the demand for reliability is high. Therefore, in the refrigerator 1 of the present embodiment, the two-way valve 100 is provided in the middle of the refrigerant flow path between the dew condensation prevention pipe 43 through which the high-temperature refrigerant flows and the first capillary tube 44a.

  In addition, when a high-temperature refrigerant flows in the two-way valve 100 as in this embodiment, providing the two-way valve 100 in each storage chamber has a problem of reducing the storage space in the storage chamber due to the volume of the two-way valve 100. There arises a problem that heat is exchanged between the air in the low temperature storage chamber and the high temperature refrigerant to heat the storage chamber. Since heating in the storage chamber causes a decrease in energy saving performance, the two-way valve 100 is installed in the machine room 19 outside the heat insulating box 10 in the refrigerator 1 of the present embodiment. That is, the two-way valve 100, which is a kind of refrigerant flow control means, is disposed in the refrigerant flow path between the condensation prevention pipe 43 and the capillary tube 44, which is a kind of decompression means, and is disposed outside the storage chamber. ing.

(Example 2)
Next, the refrigerant flow path configuration of the refrigerator 1 of Example 2 will be described with reference to FIG. The refrigerator 1 of the second embodiment is a refrigerator that can change the throttle strength of the first refrigerant flow path A by using an expansion valve 120 that can control the strength of the throttle instead of the two-way valve 100 of the first embodiment. . In addition, about the member same as Example 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  FIG. 13 is a diagram illustrating a refrigeration cycle (refrigerant flow path) configuration of the refrigerator according to the second embodiment. In the refrigerator according to the second embodiment, the third capillary tube 44c is provided instead of the first capillary tube 44a, and the expansion valve 120 is provided instead of the two-way valve 100 as compared with the refrigerator according to the first embodiment. In addition, instead of the three-way valve 110 having the three modes A, B, and O provided in the refrigerator 1 of the first embodiment, the refrigerator of the second embodiment has an A mode in which the inlet 111i and the outlet 111o_A are communicated with each other. A three-way valve 111 having two modes, a B mode for communicating the inflow port 110i and the outflow port 110o_B, is provided.

  The three-way valve 111 switches between the first refrigerant flow path A provided with the dew condensation prevention pipe 43 and the second refrigerant flow path B that bypasses the dew condensation prevention pipe 43. In the first refrigerant flow path A, after passing through the outlet 111o_A of the three-way valve 111, it flows to the expansion valve 120 via the refrigerant pipe 76, the dew condensation prevention pipe 43, and the refrigerant pipe 78, and from the expansion valve 120 to the refrigerant pipe 79. The refrigerant flows into the third capillary tube 44c through the refrigerant tube 80, and the refrigerant flows from the third capillary tube 44c through the refrigerant pipe 80 to the refrigerant junction 200. That is, the decompression means is configured by combining the expansion valve 120 and the capillary tube 44. Other configurations of the refrigeration cycle are the same as those in the first embodiment.

  The third capillary tube 44c is narrower than the second capillary tube 44b, and is suitable for a large heat load. That is, the plurality of capillary tubes 44 have different apertures. The expansion valve 120 is a refrigerant flow path control means for controlling the opening and closing of the refrigerant flow path, as well as the two-way valve 100 of the first embodiment, and is also a pressure reducing means for reducing the pressure of the refrigerant. The expansion valve 120 of the present embodiment includes an open mode in which communication between the refrigerant pipe 79 and the refrigerant pipe 80 is suppressed as much as possible, and a valve body (not shown) provided in the expansion valve 120. A pressure reducing mode is provided in which a part of the outlet (not shown) is closed to reduce the cross-sectional area of the refrigerant flow path. A plurality of stages are provided in the decompression mode, and the strength of the diaphragm can be finely adjusted. Furthermore, the expansion valve 120 has a closed mode for closing the refrigerant flow path.

  The effect acquired by the structure of the refrigerator 1 of Example 2 shown above is demonstrated below.

  In the refrigerator 1 of the second embodiment, the expansion valve 120 is set to the open mode, the refrigerant is decompressed only by the third capillary tube 44c, and the expansion valve 120 is set to the decompression mode, and the expansion valve 120 and the third capillary tube are set. The throttle strength is switched by switching the mode in which the refrigerant is depressurized by both 44c. Thereby, it can adjust so that it may become the optimal aperture | strength intensity | strength in each of the case where a thermal load is small and large. Specifically, after the specification of the third capillary tube 44c is determined so that the optimum throttle strength is obtained when the thermal load is large, the cross-sectional area of the refrigerant flow path in the expansion valve 120 is small. The position of a valve body (not shown) in the expansion valve 120 in the pressure reducing mode is determined so as to obtain an optimum throttle strength. Thus, when the heat load is small, the expansion valve 120 is set to the decompression mode, and when the heat load is large, the expansion valve 120 is set to the open mode, so that the optimum throttle strength can be obtained in any case. it can. That is, in the refrigerator 1 according to the second embodiment, the strength of the throttling can be adjusted so that the optimal evaporation pressure can be obtained both when the heat load is large and when the heat load is small. A high-performance refrigerator can be obtained.

  In addition, the expansion valve 120 according to the second embodiment includes a plurality of stages in the decompression mode, and the throttle strength that can be set can be finely adjusted instead of the two stages of the open mode and the decompression mode. Therefore, the refrigerator 1 of the present embodiment can adjust the strength of the throttle more flexibly according to the heat load in the storage chamber, and can be controlled to the optimum evaporation pressure under more conditions.

  Next, in the refrigerator 1 of the second embodiment, in the first refrigerant flow path A, the reason is that the refrigerant is decompressed not only by the expansion valve 120 but also by the two decompression means of the expansion valve 120 and the third capillary tube 44c. Will be explained.

  The capillary tube 44 also has a function as a heat exchanging unit 47 for exchanging heat with the refrigerant in the refrigerant pipe 84 in addition to the function as a decompression unit. As described with reference to FIG. 8 in the first embodiment, by providing the heat exchanging portion 47, the amount of heat absorbed in the evaporator 7 is increased, and the energy saving performance is improved. Therefore, the refrigerator 1 of Example 2 can obtain the energy saving performance improvement effect by the heat exchange unit 47 by providing the third capillary tube 44 c in addition to the expansion valve 120.

  Next, the reason why the expansion valve 120 is provided on the first refrigerant flow path A side where the refrigerant flows through the dew condensation prevention pipe 43 will be described below.

  As described so far, the throttle when the heat load is small is made stronger than the case where the heat load is large, and the first refrigerant flow path A according to the temperature and humidity around the refrigerator 1 is further increased. It is effective to improve the energy saving performance to switch the second refrigerant flow path B alternately. Therefore, when the heat load is small, both the first refrigerant flow path A and the second refrigerant flow path B are made strong throttles, and the first refrigerant flow path A and the second refrigerant flow path B are alternately arranged. It is better to switch. Here, as in this embodiment, when the expansion valve 120 is provided only in one of the refrigerant flow paths, only the refrigerant flow path can change the throttle strength of the refrigeration cycle. The throttle of the refrigeration cycle is fixed in a strong throttle state in accordance with a small heat load. That is, the refrigerant flow path whose diaphragm is weakened is only the refrigerant flow path on the side passing through the expansion valve 120. Therefore, when the heat load is large and it is desired to weaken the throttle, it is necessary to flow the refrigerant through the refrigerant flow path on the side passing through the expansion valve 120. If the expansion valve 120 is provided only on the second refrigerant flow path B side, the refrigerant is always flowed to the second refrigerant flow path B side in order to weaken the throttle. If the refrigerant continues to flow through the second refrigerant flow path B, the partition walls 28, 29, and 30 that suppress dew condensation by the dew condensation prevention pipe 43 are not heated, and the possibility that dew condensation occurs on these wall surfaces increases.

  On the other hand, when the expansion valve 120 is provided on the first refrigerant flow path A side where the dew condensation prevention pipe 43 is provided as in this embodiment, the first refrigerant flow path A side is provided when the throttle is weakened. Since it is fixed, dew condensation can be suppressed even when the heat load in the storage chamber of the refrigerator 1 is large and the humidity around the refrigerator 1 is high.

  Further, by providing the expansion valve 120 on the first refrigerant flow path A side and further providing the expansion valve 120 with a closed mode, the two-way valve 100 of the first embodiment can also serve as the role. That is, the expansion valve 120 having the closed mode is provided between the dew condensation prevention pipe 43 and the third capillary tube 44c, and the expansion valve 120 is set to the closed mode when the compressor 24 is stopped. The effect of improving the energy saving performance by suppressing the inflow of the high-temperature refrigerant to the evaporator 7 is also obtained.

Example 3
Next, the refrigerant flow path configuration of the refrigerator 1 of Example 3 will be described with reference to FIGS. 14, 15a, 15b, and 15c. The refrigerator 1 of Example 3 is a refrigerator that can change the strength of the throttle in both the first refrigerant flow path A and the second refrigerant flow path B. In addition, about the member same as Example 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  FIG. 14 is a diagram illustrating the configuration of the refrigeration cycle (refrigerant flow path) of the refrigerator according to the third embodiment. In the refrigerator 1 of the present embodiment, the first refrigerant flow path A and the second refrigerant flow path B are switched by the first three-way valve 111 similar to that of the second embodiment, and the fourth three-way valve 112 which will be described later is used for the fourth. This is a refrigerator that switches between the capillary tube 44d and the fifth capillary tube 44e. Similar to the first capillary tube 44a and the second capillary tube 44b of the first embodiment, the fourth capillary tube 44d is adjusted so as to have an appropriate throttle strength with a small thermal load. The fifth capillary tube 44e is adjusted so as to have an appropriate diaphragm strength in a state where the heat load is large, and the diaphragm strength is made weaker than that of the fourth capillary tube 44d.

  The first three-way valve 111 switches between two modes: an A mode for communicating the inlet 111i and the outlet 111o_A and a B mode for communicating the inlet 111i and the outlet 111o_B. On the other hand, the second three-way valve 112 includes a D mode for communicating the inlet 112i and the outlet 112o_D, an E mode for communicating the inlet 112i and the outlet 112o_E, and an outlet 112o_D of the three-way valve 112. There are three modes of the X mode in which both of the outlets 112o_E are closed. The refrigerator 1 according to the third embodiment includes a check valve 210 and a refrigerant junction portion 201. The check valve 210 is a member that allows the refrigerant to pass only in one direction. Similarly to the refrigerant junction part 200, the refrigerant junction part 201 is a member that is connected to three refrigerant pipes and always makes them communicate.

  Next, the relationship between each component member and each connection pipe will be described. A structure similar to that of the first embodiment is omitted. The other end of the connection pipe 74 connected to the wall surface heat radiation pipe 42 is connected to the inlet 111 i of the first three-way valve 111. The outlet 111o_A of the first three-way valve 111 is connected to the connecting pipe 76, and the outlet 110o_B is connected to the connecting pipe 77.

  The connection pipe 76 is connected to the dew condensation prevention pipe 43, and the other end of the dew condensation prevention pipe 43 is connected to the check valve 210 by the connection pipe 78. The check valve 210 and the refrigerant merging portion 201 are connected by a connection pipe 85. The other end of the connection pipe 77 connected to the outlet 111o_B of the first three-way valve is also connected to the refrigerant junction portion 201. The refrigerant junction 201 is connected to the refrigerant pipe 86 together with the refrigerant pipes 85 and 77 described above. The other end of the refrigerant pipe 86 is connected to the dryer 45, and the dryer 45 and the inlet 112 i of the second three-way valve 112 are connected by the refrigerant pipe 87. The outflow port 112o_D of the second three-way valve 112 is connected to the fourth capillary tube 44d through a connection pipe 88, and the outflow port 112o_E is connected to the fifth capillary tube 44e through a connection pipe 89. Other configurations are the same as those of the first embodiment.

  As for the control of the first three-way valve 111, the A mode and the B mode of the first three-way valve 111 according to the ambient temperature and humidity of the refrigerator 1 as in the three-way valve 110 of the first embodiment shown in FIG. By switching to a proper heating amount, the refrigerant in the dew condensation prevention pipe 43 suppresses dew condensation, while suppressing excessive heating and performing a cooling operation with high energy saving performance. The second three-way valve 112 is switched according to a change in the heat load. When the heat load is low, the second three-way valve 112 is set to the D mode so that the refrigerant flows through the fourth capillary tube 44d having a strong throttle and the heat load is high. In this case, the mode is set to the E mode so that the refrigerant flows through the fifth capillary tube 44e having a weak throttle. When the compressor 24 is stopped, the second three-way valve 112 is set to the X mode instead of the two-way valve 100 of the first embodiment, and the first three-way valve 111 is set to the A mode.

  The effect obtained by the refrigerator 1 of Example 3 shown above is demonstrated below.

  In the refrigerator 1 of the third embodiment, the heating amount of the dew condensation prevention pipe 43 is controlled by the first three-way valve 111 according to the temperature and humidity around the refrigerator 1, and the second three-way valve 112 is used according to the heat load. Since the evaporation pressure is controlled, the heating amount and the evaporation pressure can be controlled separately. Therefore, the energy saving performance can be enhanced by suppressing excessive heating by the dew condensation prevention pipe 43 without being influenced by the heat load.

  In the refrigerator 1 according to the third embodiment, the two capillary tubes 44 can be switched according to the heat load. Therefore, the specification of the fourth capillary tube 44d is set to the strength of the throttle suitable for the case where the heat load is small. The specification of the fifth capillary tube 44e is set to a diaphragm strength suitable for a large heat load. Therefore, the strength of the throttle can be adjusted so that the optimal evaporation pressure is obtained in both cases where the heat load is large and small.

  Next, the reason for providing the X mode that closes both the outlet 112o_D and the outlet 112o_E of the second three-way valve 112 will be described. The second three-way valve 112 is provided between the dew condensation prevention pipe 43 and the capillary tube 44, and when the compressor 24 is stopped, the second three-way valve 112 is set to the X mode. Since both the outflow port 112o_D and the outflow port 112o_E are closed, the refrigerant flow path on the upstream side and the downstream side of the second three-way valve 112 can be closed. Therefore, the high-temperature refrigerant from the compressor 24 to the dew condensation prevention pipe 43 cannot flow into the evaporator 7 when the compressor 24 is stopped, and an increase in the heat load in the storage chamber due to the high-temperature refrigerant can be suppressed. That is, by using the second three-way valve 112 having the X mode, an effect equivalent to that of the two-way valve 100 of the first embodiment can be obtained without using a new valve. The size of the machine room 19 is basically determined by the width of the refrigerator 1, and in addition to the valves, the machine room 19 is provided with a compressor 24, a heat radiator 41 outside the storage room, and the like. Further, an increase in cost caused by an increase in valves can be suppressed.

  Further, in the refrigerator 1 of the present embodiment, a check valve 210 is provided between the dew condensation prevention pipe 43 and the refrigerant junction portion 201. Comparing the amount of heat released when flowing the refrigerant through the first refrigerant flow path A and when flowing the refrigerant through the second refrigerant flow path B, the direction of the first refrigerant flow path A that also radiates heat in the dew condensation prevention pipe 43 However, the amount of heat release is large and the condensation pressure tends to be low. Therefore, when the first three-way valve 111 is switched from the A mode to the B mode, the refrigerant flows into the dew condensation prevention pipe 43 that has a relatively low condensation pressure in the first refrigerant flow path A. The pressure in the part 201 is a relatively high condensing pressure in the second refrigerant flow path B. Further, when no refrigerant flows through the dew condensation prevention pipe 43, the temperature of the refrigerant staying in the dew condensation prevention pipe 43 is lowered by the adjacent freezer compartment 60, and thus the pressure further decreases. For this reason, if the check valve 210 is not provided, the refrigerant flows from the refrigerant confluence portion 201 to the dew condensation prevention pipe 43 side where the pressure is low, and the amount of refrigerant staying in the dew condensation prevention pipe 43 increases. As a result, the refrigerant that can be circulated is insufficient and the cooling capacity is lowered. Therefore, the check valve 210 is provided so that the refrigerant does not flow into the dew condensation prevention pipe 43.

  The above is the effect which the refrigerator of Example 3 shown in FIG. 14 has. Next, FIG. 15a, FIG. 15b, and FIG. 15c show modifications of the configuration of the refrigeration cycle (refrigerant flow path) that can achieve the same effect as this effect.

(Modification 1)
FIG. 15 a is a diagram illustrating a refrigeration cycle related to the first modification of the third embodiment using the four-way valve 130 and the three-way valve 113. In the refrigerator 1 shown in FIG. 15a, a four-way valve 130 is provided instead of the first three-way valve 111 and the check valve 120 of the refrigerator of the third embodiment, and a three-way valve 113 is provided instead of the second three-way valve 112. . The four-way valve 130 includes an inlet 130_i, an outlet 130_A1, an inlet 130_A2, and an outlet 130_C. The four-way valve 130 has three modes, the A mode in which the inlet 130_i and the outlet 130_A1 are connected, the inlet 130_A2 and the outlet 130_C are connected, the outlet 130_A1 and the inlet 130_A2 are closed, and the inlet A B mode in which 130_i and the outlet 130_C are communicated, and an X mode in which both the outlet 130_A1 and the inlet 130_A2 are communicated with the inlet 110i and the outlet 130_C is closed are provided. The inflow port 130 — i is connected to the wall surface heat radiating pipe 72 by a refrigerant pipe 74. The outflow port 130_A1 is connected to the dew condensation prevention pipe 43 by the refrigerant pipe 90, and the inflow port 130_A2 is connected to the other end of the dew condensation prevention pipe 43 by the refrigerant pipe 91. The outlet 130 </ b> _C is connected to the dryer 45 by a refrigerant pipe 86. The three-way valve 113 includes an inflow port 113i, an outflow port 113o_D, and an outflow port 113o_E, and a D mode that allows the inflow port 113i and the outflow port 113o_D to communicate with each other, and an E that connects the inflow port 113i and the outflow port 113o_E. There are two modes.

  When the four-way valve 130 is operated in the A mode, the refrigerant that has entered the four-way valve 130 from the inflow port 130_i flows from the outflow port 130_A1 to the dew condensation prevention pipe 43 via the refrigerant pipe 90, and passes through the refrigerant pipe 91 from the dew condensation prevention pipe 43. Through the inflow port 130_A2 and the outflow port 130_C. On the other hand, when the four-way valve 130 is operated in the B mode, the refrigerant that has entered the four-way valve 130 from the inflow port 130_i flows directly to the outflow port 130_C, and no refrigerant flows to the dew condensation prevention piping 43 side.

  With the above configuration, in the refrigerator shown in FIG. 15 a, the switching of the first refrigerant flow path A for flowing the refrigerant to the dew condensation prevention pipe 43 and the second refrigerant flow path B for bypassing the dew condensation prevention pipe 43 is performed by the four-way valve 130. This is realized by switching between A mode and B mode. Further, by closing the outlet 130_A1 and the inlet 130_A2 in the B mode, the refrigerant shortage due to the refrigerant staying in the dew condensation prevention pipe 43 is prevented as in the check valve 210 of the third embodiment.

  Further, the four-way valve 130 has an X mode, and when the compressor 24 is stopped, the four-way valve 130 is in the X mode. As a result, the refrigerant flow path between the dew condensation prevention pipe 43 and the capillary tube 44 can be closed as in the closed mode of the two-way valve 110 in the first embodiment and the X mode of the three-way valve 112 in the third embodiment. It is also possible to obtain an effect of preventing the high-temperature refrigerant from flowing into the evaporator 7 when the compressor 24 is stopped.

  Further, the four-way valve 130 is configured to communicate both or one of the outlet 130_A1 and the inlet 130_A2 with the inlet 130_i in the X mode. Thereby, in the refrigerator of Example 3, the same effect as having made the three-way valve 111 into A mode when the compressor 24 stops is acquired. That is, when the dew condensation prevention pipe 43 becomes low temperature, the high temperature refrigerant on the upstream side of the four-way valve 130 flows into the dew condensation prevention pipe 43, thereby making it easy to suppress dew condensation.

  Even if the four-way valve 130 does not have the X mode, if the three-way valve 113 is a three-way valve having the same X mode as the three-way valve 112 shown in FIG. 14, the four-way valve 130 is in the A mode when the compressor 24 is stopped. The same effect can be obtained by setting the three-way valve 113 to the X mode.

(Modification 2)
Next, the refrigeration cycle configuration of FIG. 15b will be described. FIG. 15 b is a diagram illustrating the configuration of the refrigeration cycle in the second modification of the third embodiment using the five-way valve 140. The refrigerator shown in FIG. 15b includes a five-way valve 140 instead of the first three-way valve 111, the check valve 120, and the second three-way valve 112 in the refrigerator of the third embodiment shown in FIG. The five-way valve 140 includes an inlet 140_i, an outlet 140_A1, an inlet 140_A2, an outlet 140_D, and an outlet 140_E.

  The five-way valve 140 has five modes: an A-D mode, an A-E mode, a BD mode, a BE mode, and an X mode. In the A-D mode, the inlet 140_i and the outlet 140_A1 are communicated with each other, and the inlet 140_A2 and the outlet 140_D are communicated with each other. In the AE mode, the inlet 140_i and the outlet 140_A1 are communicated, and the inlet 140_A2 and the outlet 140_E are communicated. In the BD mode, the inlet 140_i and the outlet 140_D are communicated. In the BE mode, the inlet 140_i and the outlet 140_E are communicated, and the outlet 140_A1 and the outlet 140_A2 are in the BD mode, BE It is blocked in both modes. In the X mode, the outlet 140_A1 and / or the inlet 140_A2 are communicated with the inlet 140_i, and the outlet 140_D and the outlet 140_E are closed.

  The inflow port 140 — i is connected to the dryer 45 by a refrigerant pipe 75. The outflow port 140_A1 is connected to the dew condensation prevention pipe 43 by the refrigerant pipe 90, and the inflow port 140_A2 is similarly connected to the dew condensation prevention pipe 43 by the refrigerant pipe 91. The outlet 140_D is connected to the fourth capillary tube 44d by the refrigerant pipe 88, and the outlet 140_E is connected to the fifth capillary tube 44e by the refrigerant pipe 89. Others are the same as FIG.

  When the five-way valve 140 is set to the A-D mode and the AE mode, the refrigerant flowing into the five-way valve 140 from the inlet 140_i flows from the outlet 140_A1 to the condensation prevention pipe 43 via the refrigerant pipe 90, The dew condensation prevention pipe 43 flows again into the five-way valve 140 from the inlet 140_A2 through the refrigerant pipe 91. In the A-D mode, the gas flows from the outlet 140_D to the fourth capillary tube 44d, and in the A-E mode, the gas flows from the outlet 140_E to the fifth capillary tube 44e.

  On the other hand, when the five-way valve 140 is set to the BD mode, the refrigerant flowing into the five-way valve 140 from the inflow port 140_i flows directly to the fourth capillary tube 44d through the outflow port 140_D, and is in the BE mode. Then, since the refrigerant flowing in from the inlet 140_i flows directly from the outlet 140_E to the fifth capillary tube 44e, the refrigerant does not flow to the dew condensation prevention pipe 43 side in the BD mode and BE mode.

  From the above configuration, the five-way valve 140 in FIG. 15b switches between [AD mode or AE mode] and [BD mode or BE mode] with one refrigerant flow path control means. Thus, the first refrigerant channel A and the second refrigerant channel B are switched. Further, by switching between [AD mode or BD mode] and [AE mode or BE mode], the fourth capillary tube 44d and the fifth capillary tube 44e having different diaphragms are switched. Thereby, the heating amount and the evaporation pressure can be controlled. Moreover, since the refrigerant flow path from the dew condensation prevention pipe 43 to the evaporator 7 can be closed by providing the X mode in the five-way valve 140, the five-way valve 140 is set to the X mode when the compressor 24 is stopped. Thus, the high-temperature refrigerant from the compressor 24 to the dew condensation prevention pipe 43 is prevented from flowing into the evaporator 7. Therefore, the five-way valve 140 can control the amount of heating by the anti-condensation piping, suppress the flow of the high-temperature refrigerant into the evaporator, and control the evaporation pressure. As in the refrigerator shown in FIG. A high-performance refrigerator can be obtained.

(Modification 3)
Next, the configuration of the refrigeration cycle in FIG. 15c will be described. FIG. 15 c is a diagram illustrating the configuration of the refrigeration cycle according to the third modification of the third embodiment using the four-way valve 130 and the expansion valve 121. In the refrigerator shown in FIG. 15c, instead of the first three-way valve 111 and the check valve 120 in the refrigerator shown in FIG. 14, a four-way valve 130 is provided, a second three-way valve 112, a fourth capillary tube 44d, Instead of the fifth capillary tube 44e, an expansion valve 121 and a third capillary tube 44c are provided. The expansion valve 121 is connected to the dryer 45 and the third capillary tube 44 c by the refrigerant pipe 87 and the refrigerant pipe 79, and the other end of the third capillary tube 44 c is connected to the evaporator 7 by the refrigerant pipe 82. Other pipe connections and the four-way valve 130 are the same as in FIG.

  The expansion valve 121 of the present embodiment has an open mode in which the pressure reduction between the refrigerant pipe 87 and the refrigerant pipe 79 is suppressed as much as possible, and a pressure reduction between the refrigerant pipe 79 and the refrigerant pipe 80 by reducing the refrigerant flow path. A decompression mode is provided. Further, the decompression mode is provided with a plurality of stages, and the throttle strength of the expansion valve 121 can be finely adjusted. The throttling strength of the third capillary tube 44c is adjusted so as to obtain an appropriate amount of pressure reduction when the heat load is large. When the thermal load is small, the expansion valve 121 is set in a pressure reduction mode, and an appropriate evaporation pressure is obtained by the two pressure reduction means of the expansion valve 121 and the third capillary tube 44c.

  With the above configuration, the amount of heating by the dew condensation prevention pipe 43 can be controlled by switching between the A mode and the B mode of the four-way valve 130, and the evaporation pressure of the refrigerant can be controlled by the expansion valve 121. Further, in the refrigerator shown in FIG. 15c, the four-way valve 130 has an X mode, and when the compressor 24 is stopped, the four-way valve 130 is set to the X mode, so that the high temperature from the compressor 24 to the dew condensation prevention pipe 43 can be increased. The refrigerant can be prevented from flowing into the evaporator 7 when the compressor 24 is stopped. That is, it is possible to control the amount of heating by the dew condensation prevention pipe, to suppress the inflow of high-temperature refrigerant to the evaporator, and to control the evaporation pressure. As with the refrigerator shown in FIG. 14, a refrigerator with high energy saving performance is obtained. It is done. Even when the four-way valve 130 does not have the X mode, the expansion valve 121 is provided with a closed mode for closing the refrigerant flow path so that the four-way valve 130 is in the A mode and the expansion valve 121 is in the closed mode when the compressor 24 is stopped. By doing so, the same effect can be obtained.

  The above is the refrigerator of Examples 1 to 3.

  In addition, this invention is not limited to each Example mentioned above, Various modifications are included. For example, each of the above-described embodiments has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to one having all the configurations described. Further, a part of the configuration of a certain embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of a certain embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  Further, in the embodiments described in the present specification, the refrigerant flow path capable of obtaining the above-described effect is formed with a relatively small number of refrigerant flow path control means within two. If the same refrigerant flow path can be formed, the number and form of the refrigerant flow path control means are not necessarily limited. However, considering the space and cost for installing the refrigerant flow path control means, as in this embodiment, It is desirable to use as few refrigerant flow path control means as possible. The check valve may be replaced with a refrigerant flow path control means such as a two-way valve. Further, only the minimum mode is described for each refrigerant flow path control means in each embodiment. For example, the three-way valve 111 of the embodiment 2 shown in FIG. 13 has only an A mode, a B mode, and two modes. However, the O mode of the three-way valve 110 shown in FIG. 3 and the X mode of the three-way valve 112 shown in FIG. 14 may be provided.

1 Refrigerator 2 Cold room (storage room)
3 Ice making room (storage room)
4 Upper freezer room (storage room)
5 Lower freezer compartment (storage room)
6 Vegetable room (storage room)
7 Evaporator 9 Fan in storage room 10 Heat insulation box 24 Compressor 28 Refrigeration room-freezing room partition wall (partition)
29 Freezer compartment-vegetable compartment partition wall
30 Freezer compartment partition wall (partition)
33 Refrigerating room temperature sensor 34 Vegetable room temperature sensor 35 Freezer room temperature sensor 36 Evaporator temperature sensor 37 Outside air temperature sensor 38 Outside air humidity sensor 41 Storage room outdoor radiator (heat radiation means)
41a Fan outside storage room 42 Wall heat radiation pipe (heat radiation means)
43 Condensation prevention piping 44 Capillary tube (pressure reduction means)
44a First capillary tube 44b Second capillary tube 44c Third capillary tube 44d Fourth capillary tube 44e Fifth capillary tube 45 Dryer 46 Gas-liquid separator 47 Heat exchange section 50 Refrigeration chamber damper 52 Freezing chamber damper 60 Freezer compartment 100 Two-way valve (refrigerant flow path control means)
110, 111, 112, 113 Three-way valve (refrigerant flow path control means)
120, 121 expansion valve (throttle amount control means / refrigerant flow path control means)
130 Four-way valve (refrigerant flow path control means)
140 Five-way valve (refrigerant flow path control means)
200, 201 Refrigerant merging section 210 Check valve (backflow prevention means)

Claims (5)

A heat insulating box having an opening edge that forms an opening in the front, a door that opens and closes the opening, a storage chamber formed by the door and the heat insulating box, a compressor, a heat radiating means, and the opening edge. In a refrigerator provided with a dew condensation prevention pipe for heating, a decompression means, and an evaporator,
A first refrigerant flow path through which the refrigerant discharged from the discharge port of the compressor flows in the order of the heat dissipating means, the dew condensation prevention pipe, the pressure reducing means, the evaporator, and the suction port of the compressor;
A second refrigerant flow path for causing the refrigerant discharged from the discharge port of the compressor to flow in the order of the heat dissipating means, the pressure reducing means, the evaporator, and the suction port of the compressor,
Between the heat dissipation means and the condensation prevention pipe, and between the condensation prevention pipe and the evaporator, a refrigerant flow path control means is provided,
The refrigerant flow path control means switches the first refrigerant flow path and the second refrigerant flow path, changes the throttle of the decompression means, and the refrigerant flow path between the dew condensation prevention pipe and the evaporator. A refrigerator characterized by switching between communication and blockage.   The decompression means is composed of a plurality of capillary tubes, and the refrigerant flow control means causes the refrigerant to flow through any one of the plurality of capillary tubes and the refrigerant to flow through the plurality of capillary tubes. The refrigerator according to claim 1, wherein the aperture is changed by switching between the two.   The refrigerator according to claim 2, wherein the plurality of capillary tubes have different throttles.   The refrigerator according to claim 1, wherein the decompression unit is configured by combining an expansion valve and a capillary tube.   5. The refrigerant flow control means according to claim 1, wherein the refrigerant flow control means is disposed outside the storage chamber in a refrigerant flow path between the dew condensation prevention pipe and the decompression means. The refrigerator in any one.