refrigerator

Abstract

To provide a highly reliable refrigerator which makes dew condensation and frost formation less likely to occur in a heat insulation wall even if an internal gap which allows air to circulate to the interior and the exterior of the refrigerator exists in the heat insulation wall.SOLUTION: A refrigerator includes: a heat insulation box body which is formed including a heat insulation material; and a refrigeration cycle in which a refrigerant circulates. The refrigeration cycle includes: a cooler housed inside the heat insulation box body; a compressor 24 housed outside the heat insulation box body; and a return pipe 58 which connects the downstream side of the cooler with the upstream side of the compressor 24. The return pipe 58 is guided to the outside of the heat insulation box body through a gap of the heat insulation box body. In the gap, air exists and a heat exchange part 57 for heating a portion, which passes through the gap, and a portion at the upstream side of the forementioned portion of the return pipe 58 is disposed.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a refrigerator. [Background technology]

[0002] Patent Document 1 discloses a refrigerator in which a compressor, a condenser, a capillary tube, an evaporator, an accumulator, and a suction pipe are connected in sequence and return to the compressor, and in which heat exchange is performed by joining the capillary tube and the suction pipe within the insulating material on the back side of the refrigerator outer shell, which is made up of an outer box made of a metal plate, an inner box made of a resin molded product, and an insulating material filled between the two. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-65946 Summary of the Invention [Problem to be solved by the invention]

[0004] In the refrigerator described in Patent Document 1, the suction pipe leading from the evaporator to the compressor is configured to exchange heat with a capillary tube inside the insulation. The refrigerant, cooled in the evaporator to cool the refrigerator, is introduced into the insulation while maintaining its low temperature. If there are internal gaps within the insulation that allow air to circulate between the inside and outside of the refrigerator, condensation or frost may form on the surface of the low-temperature suction pipe. Condensed water or melted frost may flow down and seep into the insulation walls, causing problems such as water leaking from unintended locations. [Means for solving the problem]

[0005] The refrigerator of the present invention includes an insulated box body formed to include a thermal insulating material, and a refrigeration cycle in which a refrigerant circulates. The refrigeration cycle includes a cooler housed in the insulated box body, a compressor housed outside the insulated box body, and an outlet pipe connecting a downstream side of the cooler and an upstream side of the compressor. The outlet pipe is led to the outside of the insulated box body through a gap in the insulated box body, and air is present in the gap. A heating unit is disposed to heat a portion of the outlet pipe that passes through the gap and a portion upstream of the gap, or a portion of the outlet pipe that is upstream of the portion that passes through the gap. The temperature of the outlet pipe upstream of the gap reaches or exceeds the dew point. There are. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a front view of a refrigerator according to an embodiment of the present invention. [Figure 2] FIG. 2 is a front view of FIG. 1 with the door removed. [Figure 3] 2 is a cross-sectional view taken along the line AA in FIG. 1. [Figure 4] 2 is a cross-sectional view of FIG. 1 taken along line B-B. [Figure 5] 1 is a configuration diagram of a refrigeration cycle of a refrigerator according to an embodiment of the present invention. [Figure 6] 4 is a cross-sectional view taken along CC in FIG. 3. [Figure 7] FIG. 4 is a partially enlarged cross-sectional view of FIG. 3. [Figure 8] FIG. 2 is a partially exploded perspective view illustrating the relationship between a cooler, a return pipe, and a gutter of the refrigerator according to the embodiment. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. 2 is a perspective view of the cooling unit with the lid installed on the case. [Figure 12] 4 is a time chart showing a control state of the refrigerator according to the present embodiment. [Figure 13] FIG. 10 is a diagram illustrating a relationship between the position of a return pipe and temperature of a refrigerator according to the present embodiment. [Figure 14] FIG. 2 is a top view of the refrigerator according to the present embodiment with the top plate removed. [Figure 15] FIG. [Figure 16] FIG. 2 is a diagram showing wiring specifications of the door sensor according to the present embodiment (for right-opening doors). [Figure 17] FIG. 2 is a diagram showing wiring specifications of the door sensor according to the present embodiment (for left-opening doors). [Figure 18] This is a rear view of the refrigerator according to the present embodiment with the outer panel removed. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, an embodiment of a refrigerator according to the present invention will be described with reference to FIGS. FIG. 1 is a front view of a refrigerator according to this embodiment. As shown in FIG. 1, refrigerator 1 includes a heat-insulating body 10, a door 2, and a plurality of legs 10a. In addition, a suction port 27 and an exhaust port 28 are provided on the front side (front face side) of heat-insulating body 10. Specifically, suction port 27 and exhaust port 28 are provided side by side below an opening that is closed by door 2. Suction port 27 is an opening that introduces air into machine room 25 (see FIGS. 3 and 6), which will be described later. In addition, exhaust port 28 is an opening that exhausts air from machine room 25 (see FIG. 6).

[0008] FIG. 2 is a front view of the state in which the door of FIG. 1 is removed. As shown in Fig. 2, the refrigerator 1 includes a storage compartment 3 in a refrigerated temperature range for storing food inside an insulated box 10. The storage compartment 3 includes an upper shelf 33, middle shelves 34a (front) and 34b (rear), and a lower container 35. In this embodiment, the upper surfaces of the shelves 34a and 34b are surfaces 34c on which food is placed. The shelves 34a and 34b may be fixed or detachable.

[0009] An interior light 99 is disposed, for example, on the ceiling of the storage compartment 3. The interior light 99 emits warm light such as orange, has a light axis, for example, directly below or slightly behind, and can be, for example, an LED light. The walls inside the storage compartment 3 are painted a dark color such as black. This provides the refrigerator 1 with a light source that does not look out of place even when installed in a calm space such as a bedroom, and also enables the reflection of light to be calmed. The interior light 99 can have, for example, only one light source element to give a calm impression, but it may also have two or three elements.

[0010] The insulated box 10 also includes a cooler chamber 8 in which the cooler 4 is housed, located at the rear of the lower level of the storage chamber 3. The cooler chamber 8 is arranged within the insulated box 10, including the area substantially directly below the mounting surface 34c. The storage chamber 3 is formed from above to the front of the cooler chamber 8. The storage chamber 3 is located vertically above the cooler 4, and is also located in front of (in front of) the cooler 4. The storage chamber 3 and the cooler chamber 8 are separated by a storage chamber surface member 74 (see FIG. 7).

[0011] The cooler chamber 8 is provided at its front with a return opening 22 that opens downward. The cooler chamber 8 is also provided at its rear with an internal fan 9. The internal fan 9 is a backward-facing centrifugal fan (turbo fan). An air duct 20 is provided above the internal fan 9. The air duct 20 has outlets 21a and 21b that open to the front and outlets 21c and 21d that open to the side. The air that has exchanged heat with the cooler 4 is pressurized by the internal fan 9 and sent to the storage chamber 3 through the outlets 21a, 21b, 21c, and 21d of the air duct 20, thereby cooling the interior of the storage chamber 3. The rear of the storage chamber 3 is provided with a storage chamber temperature sensor 45 (temperature estimation means) that detects the temperature of the area formed between the shelf 33 and shelves 34a and 34b. The storage chamber temperature sensor 45 is provided in the storage chamber 3, which is formed above the placement surface 34c. In addition, the rear surface of the storage chamber 3 is provided with an operation unit (not shown) that can be used to set the temperature.

[0012] Fig. 3 is a cross-sectional view taken along line AA in Fig. 1. Fig. 4 is a cross-sectional view taken along line BB in Fig. 1. As shown in Figures 3 and 4, the refrigerator 1 has steel outer panels 11 on the left and right side surfaces, back surface, and bottom exterior surfaces of the insulated box body 10. A removable top plate 12 is provided on the ceiling surface. The top plate 12 is a thin synthetic resin plate provided on the upper surface of the insulated box body 10, and is given a predetermined surface treatment to make the surface easy to clean and to enhance the design. A synthetic resin ceiling panel 13 is provided on the inside (inside) of the top plate 12. The top plate 12 is fixed with screws (not shown). A door sensor 96 (see Figure 14), a relay cable 94 (see Figure 14), an outside-compartment temperature sensor (not shown), and an outside-compartment humidity sensor (not shown) are also provided inside the top plate 12.

[0013] The refrigerator 1 also includes an inner box 18 made of synthetic resin inside the insulated box body 10. Between the outer panel 11 and the inner box 18 and between the ceiling panel 13 and the inner box 18, insulation material 5 (for example, expanded polystyrene or foamed urethane) that has been foam-molded or processed to a predetermined size is provided. That is, the refrigerator 1 does not employ a method of foaming and filling urethane into the space between the outer panel 11 or the ceiling panel 13 and the inner box 18. This eliminates the need for foaming equipment, which would be required for foaming and filling urethane, and allows for the manufacture of a refrigerator with high flexibility and reduced costs without being restricted by foaming equipment. The insulation material 5 is divided into multiple pieces, which are joined together with aluminum tape (details will be described later with reference to FIG. 18). Dividing the insulation material 5 into multiple pieces in this way improves assembly workability.

[0014] The refrigerator 1 also includes a leading edge steel plate 17 at the leading edge of the insulated box body 10. Condensation suppression piping 52, which will be described later, is installed on the inner surface of the leading edge steel plate 17. As a result, the leading edge steel plate 17, which is a metal with high thermal conductivity, acts to effectively spread heat to the leading edge of the insulated box body 10, thereby suppressing condensation.

[0015] The door 2 is provided with a detachable front panel 14 on the front surface of the door 2. The front panel 14 can be made of synthetic resin, glass, iron, or the like. The rear surface of the door 2 is provided with a synthetic resin door inner surface member 15. Between the front panel 14 and the door inner surface member 15 are a first door insulating material 7 (expanded polystyrene) that has been foamed to a predetermined size in advance and a second door insulating material 6 (urethane foam) that has been processed into a substantially rectangular parallelepiped shape and has better insulating performance than the first door insulating material 7. The top surface of the door 2 is provided with a synthetic resin top surface member 16a, and the bottom surface is provided with a synthetic resin bottom surface member 16b. A seal member 19 is disposed on the outer periphery of the inner surface of the door 2, facing the leading edge steel plate 17 of the insulated box 10. The seal member 19 has a magnet (not shown) inside it that attracts the door 2 and the insulated box 10, keeping them closed. The door inner surface member 15 is provided with a plurality of ventilation holes 15a, which allow air to circulate through the minute gaps formed between the second door insulating material 6 and the door inner surface member 15. As a result, the air in the storage chamber 3, which has been made low in humidity by the dehumidifying action of the cooler 4, acts through the ventilation holes 15a on the minute gaps formed between the second door insulating material 6 and the door inner surface member 15, making it difficult for condensation to occur due to water vapor contained in the air present between the front panel 14 and the door inner surface member 15. The ventilation holes 15a are open downward, which prevents water droplets from flowing down and entering the inside of the door inner surface member 15 through the ventilation holes, and prevents dust from falling and entering.

[0016] The refrigerator 1 also has a cooler compartment 8, which houses a cooler 4, at the rear of the lower section of the storage compartment 3. The cooler compartment 8 has a return opening 22 that opens downward on the front side. The cooler compartment 8 also has an internal fan 9 at the rear. The internal fan 9 is a backward-facing centrifugal fan (turbo fan). An air duct 20 having multiple outlets 21a-21d is provided above the internal fan 9. By using a centrifugal fan as the internal fan 9, air drawn in from the cooler compartment 8 at the front can be smoothly redirected toward the air duct 20 above, allowing for a compact installation. A gutter 30 is also provided below the internal fan 9. A drain outlet 31 is provided at the lowest point on the sloped surface of the gutter 30 to drain condensation water and melted frost generated around the internal fan 9 and the internal fan 9.

[0017] The refrigerator 1 also has a machine room 25 located below (outside) the insulated box body 10. As shown in FIG. 3, the machine room 25 includes a compressor 24 and a radiator 50 installed in a radiator air duct 160 at the front lower portion. An intake port 27 is provided at the inlet of the radiator air duct 160 in front of the radiator 50, and a filter 27a is provided in the intake port 27. The provision of the filter 27a in this manner prevents dust from accumulating on the fin surfaces of the radiator 50, which is a fin-tube heat exchanger, and thereby preventing the flow paths between the fins from shrinking or becoming blocked. As shown in FIG. 4, the machine room 25 also includes an external fan 29 and an evaporator dish 42. The external fan 29 is covered by a casing 44 that opens downward, allowing the air blown from the external fan 29 to flow over the top surface of the evaporator dish 42. An exhaust port 28 is provided in front of the evaporating dish 42, and air is drawn in through the suction port 27 (see FIG. 3) by driving the external blower 29, and the air, which has been heated by cooling the radiator 50 and the compressor 24 and exchanging heat, flows over the top surface of the evaporating dish 42 and is exhausted from the exhaust port 28. The back surface of the machine chamber 25 is covered with a removable cover 92 that does not have an intake or exhaust port. The bottom surface of the machine chamber 25 is formed by a base member 43 made of steel plate.

[0018] The refrigerator 1 also includes a heat exchanger 57 (heating unit) below the cooler 4 in the cooler compartment 8, which is formed by joining a return pipe 58 (described later) and a capillary tube 53. The cooler compartment 8 also includes a gutter 30 on its underside, and as shown in FIG. 3, a drain outlet 31 is provided at the bottom (lowest position) of the gutter 30. A drain pipe 32 is connected to the drain outlet 31, and as shown in FIG. 4, the drain pipe 32 is connected to the top of the evaporator dish 42 (communicating with the machine compartment 25 in which the compressor 24 is provided). The drain outlet 31 is located downstream of the air inlet surface 4a (see FIG. 3) of the cooler 4 and upstream (on the suction side) of the internal fan 9.

[0019] FIG. 5 is a configuration diagram of the refrigeration cycle of the refrigerator according to this embodiment. As shown in FIG. 5, the refrigeration cycle 150 of the refrigerator 1 of this embodiment includes a compressor 24, a radiator 50 (heating pipe) which is a fin-tube heat exchanger that radiates heat from the refrigerant and is connected to the compressor 24 via a discharge pipe 59, and a wall surface heat dissipation pipe 51 (heating pipe) which is a heat dissipation pipe that is connected to the radiator 50 via a connection pipe 151 (heating pipe) and is arranged so as to be in approximate contact with the inner surface of the outer panel 11 that forms the outer surfaces of the left and right side surfaces, back surface, and bottom surface of the insulated box body 10. Furthermore, the refrigeration cycle 150 includes a condensation suppression pipe 52 (heating pipe), which is a heat dissipation pipe connected to the wall surface heat dissipation pipe 51 via a connecting pipe 151 (heating pipe), arranged so as to be in approximate contact with the inner surface of the leading edge steel plate 17 of the insulated box body 10, and which heats the leading edge steel plate 17 to suppress condensation, a dryer 55 connected to the condensation suppression pipe 52 via the connecting pipe 151 and which removes moisture from the refrigerant, a capillary tube 53 (heating pipe) connected to the dryer 55 and which is a pressure reduction means for reducing the pressure of the refrigerant, and a cooler 4 connected to the capillary tube 53 and which absorbs heat from the cabinet by exchanging heat between the refrigerant and the air in the cabinet.

[0020] The refrigeration cycle 150 also includes a gas-liquid separator 54 on the piping on the outlet side of the heat transfer tube 41 that forms the cooler 4, and the outlet side of the gas-liquid separator 54 is connected to a return piping 58 (outlet piping). The return piping 58 is connected to the compressor 24. In the refrigeration cycle 150, a part of the return piping 58 serves as a heat exchanger 57 that exchanges heat with the capillary tube 53. The inner diameters of the wall surface heat radiation piping 51 and the condensation suppression piping 52 are, for example, 3.2 mm, and the inner diameter of the capillary tube 53 is, for example, 0.85 mm, which is one-third or less of the inner diameters of the wall surface heat radiation piping 51 and the condensation suppression piping 52.

[0021] Next, a description will be given of the flow of refrigerant in the refrigeration cycle 150 of the refrigerator 1 of this embodiment. In the refrigerator 1 of this embodiment, when the compressor 24 is driven, the refrigerant is compressed to become a high-temperature, high-pressure gas refrigerant, which enters the radiator 50 through the discharge pipe 59. In the radiator 50, heat is removed from the refrigerant by ventilation from the external fan 29 (see FIG. 4 ), reducing enthalpy and turning the refrigerant into a two-phase state. The refrigerant then flows into the wall surface heat dissipation pipe 51 through the connection pipe 151. In the wall surface heat dissipation pipe 51, which is disposed on both side surfaces, the bottom, and the back surface of the insulated box 10, heat exchanges mainly with the air outside the refrigerator through the outer plate 11 of the insulated box 10, further reducing enthalpy. Next, the refrigerant enters the condensation suppression pipe 52 disposed on the leading edge steel plate 17 through the connection pipe 151. In the condensation suppression pipe 52, heat exchange occurs via the leading edge steel plate 17, turning the refrigerant into a liquid refrigerant. The refrigerant then reaches the dryer 55 through the connection pipe 151, where moisture is removed, and then enters the capillary tube 53.

[0022] In the capillary tube 53, the high-temperature, high-pressure refrigerant is decompressed to become a low-temperature, low-pressure two-phase refrigerant, which reaches the inlet of the cooler 4. The refrigerant flows through the heat transfer tube 41 of the cooler 4 and exchanges heat with the air inside the refrigerator, increasing its enthalpy and dryness, and becomes a nearly saturated gas refrigerant before reaching the outlet of the cooler 4. The return pipe 58 returning from the outlet of the cooler 4 to the compressor 24 is heated by the refrigerant in the capillary tube in the heat exchange section 57, increasing its temperature (increasing its enthalpy), and returns to the compressor 24. The refrigerant sealed in the refrigeration cycle 150 is isobutane, a flammable refrigerant.

[0023] The discharge pipe 59, the radiator 50, the wall surface heat radiation pipe 51, the condensation suppression pipe 52, and the connecting pipe 151 are high-temperature, high-pressure refrigerant pipes, and the capillary tube 53 is a pressure reduction pipe that reduces the pressure of the high-temperature, high-pressure refrigerant to a low temperature and low pressure. However, since the refrigerant flowing through each of these pipes is at a temperature higher than the refrigerant at the inlet of the return pipe 58, they are heating pipes that have the ability to heat the return pipe 58.

[0024] Fig. 6 is a cross-sectional view taken along CC line in Fig. 3. Fig. 6 is a rear view of the machine room 25 and the area above it. As shown in FIG. 6 , refrigerator 1 includes compressor 24 in machine compartment 25, and external fan 29 and circuit board storage box 70 on the right side of compressor 24 in a front view (left side in a rear view). External fan 29 is mounted in casing 44, which opens downward so that air is discharged toward evaporator dish 42. By opening casing 44 toward evaporator dish 42 in this manner, air can be blown onto water accumulated in evaporator dish 42, promoting evaporation. Evaporator dish 42 is provided at its top with cover 42a, which has openings at its connection points with casing 44 and drain pipe 32, and casing 44 and drain pipe 32 are connected to the respective openings. This prevents a short circuit, in which air discharged from external fan 29 leaks out from the space between evaporator dish 42 and cover 42a and is then sucked back into external fan 29. The board storage box 70 also contains a board 71 having a power system board on which an inverter device and the like are mounted, and a control system board on which a control circuit is mounted.

[0025] Furthermore, in refrigerator 1, on the left side of compressor 24 in machine room 25 in a front view (right side in a rear view), inlet 59a of discharge piping 59 is connected to discharge port 24a of compressor 24, and outlet 58b of return piping 58 is connected to return port 24b of compressor 24. Discharge piping 59 is connected to radiator 50 (see FIG. 5), and return piping 58 is connected to cooler 4 (see FIG. 5).

[0026] On the left side of the compressor 24 as viewed from the front (on the right side as viewed from the rear), a connecting pipe 151 is provided on the outlet side (downstream side) of the condensation suppression pipe 52, and a dryer 55 is connected to the connecting pipe 151. A capillary tube 53, shown by a dashed line, is connected to the outlet side (downstream side) of the dryer 55. The capillary tube 53 is soldered (thermally contacted) with the return pipe 58, and forms a heat exchanger 57. In other words, the capillary tube 53 functions as a heating part that heats the return pipe 58 to increase the temperature of the refrigerant.

[0027] Furthermore, the return pipe 58 and the capillary tube 53 are inserted between the outside of the refrigerator (machine chamber 25) and the inside of the refrigerator (cooler chamber 8) through a communication hole 80 (gap) formed in the insulating box 10, and are led to the outside of the insulating box 10. A sealing member such as soft urethane (not shown) is installed in this communication hole 80 to fill any gaps that occur between the return pipe 58 or the capillary tube 53 and the communication hole 80. Note that although the gaps formed in the communication hole 80 are filled using the sealing member, it is difficult to fill the gaps completely, and air will remain in the communication hole 80.

[0028] Furthermore, the heat exchange section 57, which is the contact point between the capillary tube 53 and the return pipe 58, is located throughout the entirety of the communication hole 80. Furthermore, the heat exchange section 57, which is the contact point between the capillary tube 53 and the return pipe 58, is also provided in a portion of the return pipe 58 upstream of the communication hole 80. In other words, the return pipe 58 is configured to maintain contact with the capillary tube 53 after leaving the cooler 4 until it passes through the communication hole 80.

[0029] A gas-liquid separator storage space 66 is provided inside the communication hole 80. In the gas-liquid separator storage space 66, the gas-liquid separator 54 provided on the piping on the outlet side of the cooler 4 is installed approximately vertically so that the refrigerant flows from the bottom to the top. An electric heater 60 is installed as heating means at the bottom of the gas-liquid separator storage space 66. Frost may grow on the gas-liquid separator 54, which separates the low-temperature liquid refrigerant from the cooler 4, and on the surrounding piping and structures, so the provision of heating means (electric heater 60) ensures that the frost can be melted reliably. A drain outlet 62 is provided at the bottom end (lowest position) of the gas-liquid separator storage space 66, and any meltwater generated is drained through the drain outlet 62 into the gutter 30 at the bottom of the cooler chamber 8.

[0030] Furthermore, the refrigerator 1 has an outlet opening 160a of a radiator air passage 160 (see FIG. 3) at the lower front left side (right side in rear view) of the machine compartment 25, in front of the compressor 24. This allows the air that has flowed through the radiator 50 (see FIG. 3) to cool the compressor 24 well, making it less likely that a breakdown will occur due to an excessive temperature rise in the compressor 24.

[0031] Fig. 7 is a partially enlarged cross-sectional view of Fig. 3. The detailed structure of the periphery of the cooler compartment 8 of the refrigerator 1 according to this embodiment will be described with reference to Fig. 7. As shown in FIG. 7 , the refrigerator 1 is provided with a heat insulating material 75 (expanded polystyrene) and a storage compartment surface member 74 (made of synthetic resin) above the cooler compartment 8, and a flow path 76 is formed between the shelf 34b and the storage compartment surface member 74. The gap dimension L1 (flow path dimension) between the rear end 34b1 of the middle rear shelf 34b of the storage compartment 3 and the front surface 74a of the storage compartment surface member 74 facing forward is 3 mm. The gap dimension L2 (flow path dimension) between the front end 34a1 of the middle front shelf 34a and the door inner surface member 15 of the door 2 is 20 mm. The gap dimension L3 (flow path dimension) between the bottom surface 34b2 of the middle rear shelf 34b of the storage compartment 3 and the storage compartment surface member 74 located above the cooler compartment 8 is 5 mm. The front opening dimension (vertical opening dimension) L4 of the return opening 22 formed between the bottom end 74b of the storage compartment surface member 74, which forms the front surface of the return opening 22, and the surface of the inner box 18 is 30 mm. The front opening dimension L4 is the front opening dimension (vertical opening dimension) of the return opening 22. The depth opening dimension (horizontal opening dimension) L5 of the return opening 22 formed between the rear edge of the lower end 74b of the storage chamber surface member 74 and the front surface of the gutter forming member 100 is 20 mm. The depth opening dimension L5 is the depth opening dimension (horizontal opening dimension). The height dimension L6 of the cooler 4 is 50 mm. A bypass flow path 77 is formed between the upper edge (top end of the fins) of the cooler 4 and the lower surface 75a of the heat insulating material 75, and the dimension L7 of the bypass flow path is 2 mm. The thickness L8 of the heat insulating material 75 is 10 mm. The horizontal gap dimension L9 between the front edge 4s (front edge of the front-row fin) of the cooler 4 and the gutter forming member 100 is 3 mm. By ensuring the gap dimension L9 in this manner, meltwater generated when frost growing on the fins of the cooler 4 melts can be made to flow down into the gutter 30 instead of down into the storage chamber 3, thereby improving reliability. Furthermore, by setting the gap dimension L9 to 1 mm or more, for example 3 mm, as in the refrigerator 1 of this embodiment, the meltwater can be made to flow down into the gutter 30 more reliably.

[0032] Furthermore, gap dimension L1 is the gap of flow path R1 (see FIG. 7) formed behind mounting surface 34c, and gap dimension L2 is the gap of flow path R2 (see FIG. 7) formed in front of mounting surface 34c. Furthermore, gap dimension L1 is configured to be smaller than gap dimension L2 (gap dimension L1<gap dimension L2).

[0033] Furthermore, the gap dimension L3 is the gap of the flow path 76 formed in the lower part (lower surface side) of the mounting surface 34c. The gap dimension L3 is configured to be larger than the gap dimension L1 (gap dimension L1<gap dimension L3).

[0034] The front opening dimension (vertical opening dimension) L4 of the return opening 22 is configured to be larger than the depth opening dimension (horizontal opening dimension) L5 (L4 > L5). This relationship functions as a directing means for directing air so that it has a velocity component toward the upper surface of the cooler chamber 8. The lower part of the cooler 4 is open, and no wall is provided between the cooler 4 and the gutter 30. Generally, when a heat exchanger is installed in a flow path, a wall is provided around the heat exchanger to ensure that air passes through the heat exchanger. However, providing a wall between the heat exchanger and the gutter 30 hinders drainage of meltwater generated when frost melts on the cooler 4. Therefore, by opening the lower part of the cooler 4 as in the refrigerator 1 of this embodiment, meltwater can be more easily drained into the gutter 30. Furthermore, by providing a directing means for directing air so that it has a velocity component toward the upper surface of the cooler chamber 8, airflow that leaks below the cooler 4 is less likely to occur, even without a wall below the cooler 4, achieving both high heat exchange efficiency and good drainage.

[0035] Furthermore, the drain outlet 31 formed in the gutter 30 is disposed in an area downstream of the air inlet surface 4a (see FIG. 3) of the cooler 4 and upstream of the internal fan 9. Furthermore, the drain outlet 31 is connected to the downstream side of the external blower 29.

[0036] Furthermore, a drain pipe 32 connected to the drain outlet 31 of the gutter 30 passes through the insulated box body 10. That is, the drain pipe 32 passes through a through-hole 18v formed in the inner box 18, a through-hole 5v formed in the insulating material 5, and a through-hole 11v formed in the outer plate 11, and extends to an evaporation tray 42 (see FIG. 6) in the machine room 25.

[0037] Fig. 8 is a partially exploded perspective view showing the relationship between the cooler, the return pipe, and the gutter of the refrigerator of this embodiment. Fig. 9 is a cross-sectional view of the heat exchanger. As shown in FIG. 8, the cooler 4 is a fin-tube heat exchanger including a plurality of fins 40 and a heat transfer tube 41. The heat transfer tube 41 of the cooler 4 is provided with a cooler temperature sensor 46 that detects the temperature of the cooler 4. A heat exchanger 57 that thermally contacts a capillary tube 53 and a return pipe 58 is disposed at the bottom of the cooler 4. As shown in FIG. 9, the surface of the heat exchanger 57, which is the contact portion between the return pipe 58 and the capillary tube 53, is covered with a heat insulating member 90 (ethylene propylene rubber foam, for example). Note that the heat insulating member 90 is not shown in FIG. 8. The heat transfer tube inlet 41a of the cooler 4 is connected to the outlet 53a of the capillary tube 53. The heat transfer tube outlet 41b of the cooler 4 is connected to the inlet 58a of the return pipe 58.

[0038] A gutter 30 is disposed in a downward projection area of ​​the heat exchanger 57. A return pipe 58 is disposed in an upward projection area of ​​the gutter 30 (see FIG. 8). A plurality of rows of heat exchanger 57 (heating units) are disposed between the cooler 4 and the gutter 30 (two rows, front and rear, in the refrigerator 1 of this embodiment). The row downstream (front side in the front-to-rear direction) of the return pipe 58, where the temperature is higher, is disposed close to the fins on the air inlet side (front) of the cooler 4 (upstream side of the cooler's air flow) (see FIG. 7). The gutter 30 is formed by a gutter forming member 100 made of synthetic resin. The gutter forming member 100 has a first support part 101 that supports the cooler 4, a second support part 102 that supports the heat exchanger 57, and an intake port 26 of the internal fan 9.

[0039] FIG. 10 is a perspective view of a cooling unit included in the refrigerator according to this embodiment. As shown in Fig. 10, the refrigerator 1 includes a cooling unit 250. The cooling unit 250 is a unit formed by integrating the cooler 4, the internal fan 9, etc., and is provided inside the refrigerator relative to the inner box 18 (see Fig. 3). The cooling unit 250 also includes the cooler 4, the internal fan 9, a gas-liquid separator 54 (also referred to as a header or an accumulator), an electric heater 60, a return pipe 58, a capillary tube 53, and a housing 67.

[0040] The cooler 4 is a heat exchanger through which a low-temperature, low-pressure refrigerant, which has been decompressed by a capillary tube 53, flows. The cooler 4 also includes a large number of fins 40 arranged with a predetermined gap between them, and heat transfer pipes 41 that pass through these fins 40. A gutter 30 (see FIG. 3) is provided below the cooler 4 to receive condensed water.

[0041] The internal fan 9 is a blower that pressure-feeds the air cooled by the cooler 4 toward the storage chamber 3 (see FIG. 3), and is disposed on the rear side of the cooler 4. The suction side (front side) of the internal fan 9 faces the space 68 (the space on the suction side of the internal blower) in which the cooler 4 is disposed. The air cooled by the cooler 4 is sucked rearward toward the internal fan 9, and is then blown out into the storage chamber 3 (see FIG. 3) via a predetermined air flow path (see FIG. 3).

[0042] The gas-liquid separator 54 is a shell-shaped container connected downstream of the cooler 4. This gas-liquid separator 54 has the function of separating the refrigerant flowing in from the cooler 4 into gas and liquid and storing excess liquid refrigerant. The electric heater 60 is a heat source for heating the gas-liquid separator 54 and is installed below the gas-liquid separator 54. Because the gas-liquid separator 54 is easily cooled by low-temperature liquid refrigerant, the electric heater 60 is provided to melt frost that forms on the gas-liquid separator 54 and its surroundings. Note that because the liquid refrigerant is stored below the gas-liquid separator 54, the electric heater 60 may be provided on the outer surface of the gas-liquid separator 54 to directly heat the gas-liquid separator 54, or the electric heater 60 may be provided only below the outer surface of the gas-liquid separator 54 to enable efficient heating.

[0043] The return pipe 58 is a pipe that guides the gaseous refrigerant separated into gas and liquid in the gas-liquid separator 54 to the compressor 24 (see FIG. 3). The upstream end of the return pipe 58 is connected to the gas-liquid separator 54, and the downstream end is connected to the suction side of the compressor 24 (see FIG. 3). As shown in FIG. 10, the vicinity of the downstream end of the return pipe 58 extends in the vertical direction below the accommodating body 67.

[0044] The capillary tube 53 is a thin tube for decompressing the refrigerant that has passed through the compressor 24 (see FIG. 2), the radiator 50, the wall surface heat radiation piping 51, the condensation prevention piping 52, etc. in this order. The downstream end of the capillary tube 53 is connected to the cooler 4. As shown in FIG. 10, the vicinity of the downstream end of the capillary tube 53 extends in the vertical direction below the accommodating body 67 and is adjacent to the return piping 58.

[0045] The housing 67 is a resin member that houses the cooler 4, the internal fan 9, etc. The housing 67 includes a box-shaped case 67a that is open at the top, and a lid 67b (see FIG. 11) that closes the upper opening of the case 67a. The cooler 4 is installed horizontally in the case 67a. The case 67a also includes a partition plate 671a that separates the cooler 4 from the internal fan 9. The partition plate 671a has an intake port 26 formed of a circular hole in a location that corresponds to the intake side of the internal fan 9. An opening 671d is provided in a front plate 671c of the case 67a to guide air from the storage chamber 3 (see FIG. 3) to the cooler 4. A rib 671e is provided around the periphery of the opening 671d so as to protrude forward.

[0046] FIG. 11 is a perspective view of the cooling unit with the lid attached to the case. As described above, lid 67b closes the upper opening of case 67a and is L-shaped in side view. Furthermore, rib 671e (see FIG. 10) abuts against the rear surface (back surface) of lid 67b, thereby providing a predetermined gap between case 67a and lid 67b. When internal fan 9 is driven, air is guided to cooler 4 (see FIG. 10) through this gap.

[0047] As described above, the cooling unit 250 is provided closer to the interior of the refrigerator than the inner box 18 (see FIG. 3). The return pipe 58 of the cooling unit 250 passes through the through-hole 18z (see FIG. 6) formed in the inner box 18, the through-hole 5z (see FIG. 6) formed in the thermal insulation material 5, and the through-hole 11z (see FIG. 6) formed in the outer plate 11 (the top plate of the machine room 25) in the vertical direction, and extends to the compressor 24 in the machine room 25 (see FIG. 6). This eliminates the need to install the return pipe 58 in the gap between the inner box 18 and the thermal insulation material 5, thereby preventing the air in this gap from being cooled by the return pipe 58. This prevents condensation from forming in the gap between the inner box 18 and the thermal insulation material 5. Furthermore, since the outer plate 11 (see FIG. 6) does not need to be formed in a shape that does not interfere with the return pipe 58, the shape of the outer plate 11 can be simplified, and manufacturing efforts and costs can be reduced.

[0048] The return pipe 58 and the capillary tube 53 may both pass through the through holes 18z, 5z, and 11z (see FIG. 6). This reduces the number of through holes to be provided in the inner box 18 and the heat insulating material 5, thereby reducing the number of manufacturing steps and facilitating the assembly of the return pipe 58 and the capillary tube 53.

[0049] Furthermore, the return pipe 58 and the capillary tube 53 are pre-assembled to the cooling unit 250 by brazing (or soldering). In conventional refrigerators, after the cooler and the like are assembled to the housing, an operator brazes the return pipe and the capillary tube. However, heat transfer tubes often meander in a complex manner around the cooler 4, making brazing the return pipe and the capillary tube time-consuming. In contrast, in this embodiment, the return pipe 58 and the capillary tube 53 are pre-assembled to the cooling unit 250, which simplifies the assembly work of the refrigerator 1. Furthermore, because the return pipe 58 and the capillary tube 53 are included in the cooling unit 250, the work of installing the cooler 4 at a distance from the inner box 18 (see FIG. 3 ) in the vertical direction is also facilitated.

[0050] Furthermore, drain pipe 32, which guides condensation water dripping from cooler 4 into gutter 30 (see FIG. 3) to evaporating dish 42 (see FIG. 4) in machine compartment 25, has its upstream end connected to space 68 (see FIG. 10) on the suction side of internal fan 9 (see FIG. 10) and its downstream end connected to machine compartment 25 (see FIG. 3). Machine compartment 25 is connected to the space outside refrigerator 1 at atmospheric pressure. Therefore, the pressure on the suction side of internal fan 9 becomes approximately equal to atmospheric pressure. As a result, the pressure on the outlet side of internal fan 9 becomes higher than atmospheric pressure, and accordingly, the pressure in storage compartment 3 (see FIG. 3), into which low-temperature air is blown from internal fan 9, becomes higher than atmospheric pressure. As a result, positive pressure is more easily maintained in storage compartment 3, making it more difficult for air to enter storage compartment 3 from the outside. Furthermore, since air from the storage compartment 3 can easily enter the vent holes 15a for preventing condensation provided in the door 2 (see FIG. 3), condensation on the inside of the door inner surface member 15 can be suppressed.

[0051] Fig. 12 is a time chart showing the control state of the compressor and the internal fan of the refrigerator according to this embodiment, and the changes in the storage compartment temperature and shelf surface temperature. Fig. 12 shows the operating state of the refrigerator according to this embodiment when it is installed in an environment of 32°C and a relative humidity of 70%. As shown in FIG. 12, refrigerator 1 is controlled based on the temperature of storage compartment 3 detected by storage compartment temperature sensor 45 and the temperature of cooler 4 detected by cooler temperature sensor 46. Specifically, when the temperature of storage compartment 3 detected by storage compartment temperature sensor 45 reaches a cooling operation start temperature (Ton), compressor 24 and internal fan 9 are driven to start the cooling operation. When the temperature of storage compartment 3 detected by storage compartment temperature sensor 45 reaches a compressor stop temperature (Tcomp_off), compressor 24 stops, ending the cooling operation, and the refrigerator transitions to a state in which internal fan 9 is driven (fan operation). Furthermore, when the temperature of cooler 4 detected by cooler temperature sensor 46 reaches the internal fan stop temperature (Tfan_off), internal fan 9 is stopped, ending the fan operation.

[0052] In Figure 12, time t0 is the time when the temperature of storage compartment 3 detected by storage compartment temperature sensor 45 reaches the cooling operation start temperature (Ton, 3°C in this embodiment), thereby starting the cooling operation. When the cooling operation starts, compressor 24 is driven (ON), refrigerant is supplied to cooler 4, causing the temperature of cooler 4 to drop to the negative temperature range, and internal fan 9 is driven (ON), supplying cold air to storage compartment 3, causing the temperature of storage compartment 3 and the surface temperature of shelf 34b to drop at approximately the same temperature. Note that in Figure 12, the surface temperature of shelf 34b is shown as a reference temperature.

[0053] At time t1, the temperature of the storage compartment 3 detected by the storage compartment temperature sensor 45 reaches the compressor stop temperature (Tcomp_off, 1°C in this embodiment), terminating the cooling operation. The compressor 24 is stopped (OFF), and the operation shifts to fan operation, in which the internal fan 9 remains driven (ON). As a result, the internal fan 9 is driven without refrigerant being supplied to the cooler 4, causing the temperature of the cooler 4 to rise due to the heat load, and both the temperature of the storage compartment 3 and the surface temperature of the shelf 34b rise. Even at this time, the temperature of the storage compartment 3 and the surface temperature of the shelf 34b remain approximately equal. Note that the reason why there is a period during the fan operation where the temperature of the cooler 4 remains constant at around 0°C is because the frost melts during that period. Stopping the compressor 24 and driving the internal fan 9 to perform fan operation corresponds to temperature compensation means.

[0054] At time t2, the temperature of the cooler 4 detected by the cooler temperature sensor 46 reaches the internal fan stop temperature (Tfan_off, 2°C in this embodiment), causing the internal fan 9 to stop (OFF) and enter a non-operating state. As a result, air is no longer blown into the storage compartment 3, causing the temperature of the storage compartment 3 to rise. Meanwhile, the rate at which the surface temperature of the shelf 34b rises is slow due to the effects of cold storage heat in the shelf 34b and the cooler compartment 8 and natural convection.

[0055] At time t3, the temperature of storage compartment 3 detected by storage compartment temperature sensor 45 reaches the cooling operation start temperature (Ton), and the cooling operation is started again.

[0056] As described above, when the internal fan 9 is driven, the temperature of the storage compartment 3 detected by the storage compartment temperature sensor 45 and the surface temperature of the shelf 34b behave similarly and change at approximately the same rate. Therefore, the storage compartment temperature sensor 45 can be used as a temperature estimation means for estimating the surface temperature of the shelf 34b, i.e., the temperature near the underside of food placed on the shelf 34b.

[0057] Regarding the fan operation shown in FIG. 12 , if the fan operation is performed after the cumulative value of the drive time of the compressor 24 reaches a predetermined time (for example, 24 hours), the internal fan stop temperature (Tfan_off) is set 2° C. higher than that of normal fan operation, the fan operation is extended, and a defrost operation is performed to reliably melt the frost on the cooler 4. During the defrost operation, the electric heater 60 (see FIG. 6 ) installed below the gas-liquid separator storage space 66 is energized to melt frost on the gas-liquid separator 54 and the surrounding piping and structures. When the defrost operation ends, the cumulative value of the drive time of the compressor 24 is reset to 0. In the refrigerator 1 of this embodiment, the internal fan stop temperature (Tfan_off) during the defrost operation is set 2° C. higher than that of normal fan operation. However, the fan operation end temperature may be the same as that during normal fan operation, and the defrost operation may be performed by continuing the fan operation for a predetermined time (for example, 10 minutes) after the fan operation end temperature is reached.

[0058] These controls are executed by a circuit board 71 (control unit) in a circuit board storage box 70 provided in the machine room 25, which is equipped with a CPU, memories such as ROM and RAM, interface circuits, etc. The circuit board 71 is connected to an outside temperature sensor (not shown), an outside humidity sensor (not shown), a storage room temperature sensor 45, a cooler temperature sensor 46, etc. by electrical wiring (not shown), and controls the ON / OFF, rotation speed, and heating amount of the compressor 24, the inside fan 9, the outside blower 29, and the electric heater 60 based on the output values ​​of each sensor, the settings of the operation unit, programs pre-recorded in the ROM, etc.

[0059] FIG. 13 is a diagram showing the relationship between the position of the return pipe and the temperature of the refrigerator of this embodiment. The upper part of FIG. 13 shows the positions of the return pipe 58, the capillary tube 53, and the heat exchanger (heating unit) 57 that thermally contacts them, and the lower part shows the temperature of the return pipe 58 at the corresponding positions. In FIG. 13, the return pipe 58 is shown by a thick solid line, and the capillary tube 53 is shown by a two-dot chain line. The horizontal axis in the lower part of FIG. 13 represents the position from the inlet 58a (see FIG. 8) to the outlet 58b (see FIG. 6) of the return pipe 58. As shown by the arrows in the upper part of FIG. 13, the flow of refrigerant in the return pipe 58 and the flow of refrigerant in the capillary tube 53 are opposite each other. The upstream side of the return pipe 58 is the inside of the refrigerator (cooler chamber 8, gas-liquid separator storage space 66), while the upstream side of the capillary tube 53 is the outside of the refrigerator (machine chamber 25).

[0060] As shown in FIG. 13, the inlet 58a of the return pipe 58 is connected to the outlet 41a of the cooler pipe 41 (see FIG. 8), and during cooling operation, the low-temperature refrigerant (basically a gas refrigerant) that has flowed through the cooler 4 flows into the return pipe 58. Therefore, at position p0 of the inlet 58a of the return pipe 58, the return pipe temperature (the temperature of the return pipe 58) is a sufficiently low negative temperature (in this embodiment, the return pipe temperature at position p0 is −12.0°C). The return pipe temperature of the return pipe 58 begins to rise as the return pipe 58 comes into contact with the capillary tube 53 at position p1 and reaches 0°C at position p2. Thereafter, the return pipe temperature rises toward the downstream of the return pipe 58 and reaches the dew point of the outside air at position p3 (in this embodiment, the return pipe temperature at position p3 is 25.8°C (dew point of 32°C, 70% relative humidity)). Then, at position p4, the return pipe 58 reaches the communication hole 80 (in this embodiment, the return pipe temperature at position p4 is 32.2°C). Subsequently, the refrigerant reaches the outside of the refrigerator (machine room 25) at position p5 (in this embodiment, the return pipe temperature at position p5 is 33.0°C). The heat exchange section (heating section) 57 ends at position p6 (in this embodiment, the return pipe temperature at position p6 is 33.5°C), and reaches outlet 58b of return pipe 58 at position p7 (in this embodiment, the return pipe temperature at position p7 is 33.5°C), i.e., return port 24b of compressor 24 (see FIG. 6).

[0061] In the refrigerator 1 of this embodiment, the distance from position p0 to position p1 is 140 mm, the distance to position p2 is 320 mm, the distance to position p3 is 900 mm, the distance to position p4 is 1400 mm, the distance to position p5 is 1490 mm, the distance to position p6 is 1550 mm, and the distance to position p7 is 1800 mm. From these, the total length of return pipe 58 (position p7-position p0) is 1800 mm, the length of heat exchanger 57 (position p6-p1) is 1410 mm, the length L20 (position p4-p1) of heat exchanger 57 located inside the refrigerator is 1260 mm, the length L10 (position p5-p4) of heat exchanger 57 located inside communication hole 80, i.e., inside the insulating wall of insulating box 10, is 90 mm, and the length (position p6-p5) of heat exchanger 57 located outside the refrigerator is 60 mm.

[0062] The configuration of the refrigerator of this embodiment has been described above. Next, the effects achieved by the refrigerator of this embodiment will be described. The refrigerator 1 of this embodiment includes an insulated box 10 formed with a thermal insulator 5 and a refrigeration cycle 150 through which a refrigerant circulates. The refrigeration cycle 150 includes a cooler 4 housed in the insulated box 10, a compressor 24, and a return pipe 58 (outlet pipe) connecting the downstream side of the cooler 4 and the upstream side of the compressor 24. The return pipe 58 is led to the outside of the insulated box 10 through a communication hole 80 (gap) in the insulated box 10. Air is present in the communication hole 80 (gap). A heat exchanger 57 (heating unit) is disposed in the return pipe 58, heating the portion of the return pipe 58 that passes through the communication hole 80 (gap) and the portion upstream of the communication hole 80. This makes it possible to provide a highly reliable refrigerator 1 that is less susceptible to condensation and frost formation within the insulating walls (inside the communication hole 80) that form the insulated box 10. The reason for this is explained below.

[0063] Generally, a refrigerator that cools the interior of a refrigerator must be kept sufficiently cold compared to the interior temperature, so the temperature is below zero. Therefore, the refrigerant entering the return pipe from the cooler to the compressor is also a low-temperature refrigerant at a temperature below zero. If the return pipe through which this low-temperature refrigerant flows is placed inside an insulated wall with gaps through which air may be present, frosting and condensation may occur. In particular, when a method is adopted in which the interior of the insulated wall is filled with foamed urethane or a pre-formed, pre-formed insulation material is installed inside the insulated wall, as in the refrigerator of this embodiment, it is difficult to completely eliminate gaps through which air may be present. Therefore, consideration must be given to the insulated wall having gaps through which air may be present. Therefore, the refrigerator 1 of this embodiment includes a heat exchanger 57 that heats the portion of the return pipe 58 passing through the communication hole 80 and the portion upstream of this portion. This increases the temperature of the return pipe 58, which passes through the communication hole 80, making it less likely for frosting or condensation to form around the communication hole 80.

[0064] The range in which the heat exchanger 57 is provided is not limited to both the portion inside the communication hole 80 and the portion upstream of the communication hole 80, but may be only the portion upstream of the communication hole 80. Even in such a case, frost and condensation can be prevented from forming in the communication hole 80.

[0065] Furthermore, in the refrigerator 1 of this embodiment, the refrigeration cycle 150 includes heating pipes (discharge pipe 59, radiator 50, wall surface heat radiation pipe 51, condensation suppression pipe 52, connection pipe 151, and capillary tube 53) through which high-temperature refrigerant discharged from the compressor 24 flows, and includes a heat exchanger 57, which has the heating pipe in thermal contact with the return pipe 58, as a means (heating means) for heating the heating section. As a result, the return pipe 58 can be heated using the pipe of the refrigeration cycle 150, so there is no need to use a heating means such as a heater, and the refrigerator 1 can be made less likely to cause condensation or frost inside the insulating walls that form the insulating box body 10, while keeping costs down.

[0066] Furthermore, in the refrigerator 1 of this embodiment, the refrigeration cycle 150 includes, as heating pipes, heat radiation pipes (discharge pipe 59, radiator 50, wall surface heat radiation pipe 51, condensation suppression pipe 52, and connection pipe 151) through which a high-temperature, high-pressure refrigerant flows, and a capillary tube 53 (decompression pipe) that decompresses the high-temperature, high-pressure refrigerant to produce a low-temperature, low-pressure refrigerant, and the heat exchange unit 57 thermally contacts the capillary tube 53, which is the decompression pipe, with the return pipe 58. As a result, heat is exchanged between the return pipe 58 and the capillary tube 53, which has a smaller inner diameter than the heat radiation pipe, in order to achieve a decompression effect with the low-temperature return pipe 58. As a result, the refrigerant in the capillary tube 53 flows at a high flow rate and the heat transfer coefficient is increased, so that heat is easily transferred to the return pipe 58, and sufficient heat exchange can be performed with a relatively short length.

[0067] Furthermore, in the refrigerator 1 of this embodiment, the length L20 (length from position p1 to position p4 in FIG. 11 ) of the upstream side of the communication hole 80 (gap) of the heat exchanger 57 (contact portion) between the return pipe 58 and the capillary tube 53 is longer than the length L10 (length from position p4 to position p5 in FIG. 11 ) that passes through the inside of the communication hole 80 (gap). This allows the temperature of the return pipe 58 to be sufficiently increased before it reaches the communication hole 80, making it possible to provide the refrigerator 1 in which condensation and frost formation are less likely to occur inside the insulating walls that form the insulating box body 10.

[0068] Furthermore, the refrigerator 1 of this embodiment is provided with a gutter 30 below the cooler 4, and the return pipe 58 is installed in the upper projected area of ​​the gutter 30. As a result, melted water and condensation water caused by frost and condensation formed in the low-temperature portion of the return pipe 58 inside the refrigerator can be drained to the outside of the refrigerator via the gutter 30, preventing the water from flowing into unintended areas such as the storage compartment 3, resulting in a highly reliable refrigerator 1.

[0069] Furthermore, in the refrigerator 1 of this embodiment, the heating section (heat exchange section 57) is disposed in the region formed between the cooler 4 and the trough 30. This prevents frost or condensation formed on the heating section from dropping or dripping onto the cooler 4, blocking the flow path of the cooler 4, or freezing on the surface of the cooler 4, making the refrigerator 1 highly reliable.

[0070] In addition, in the refrigerator 1 of this embodiment, in the heat exchange section 57 between the return pipe 58 and the capillary tube 53, the upstream side of the refrigerant flowing through the capillary tube 53 is located close to the air inlet surface 4a (air inlet section) of the cooler 4.

[0071] In addition, in the refrigerator 1 of this embodiment, the pipes forming the heat exchange unit 57 are arranged in multiple rows below the cooler 4, and the row downstream of the refrigerant flow in the return pipe 58 forming the heat exchange unit 57 is arranged close to the fins 40 upstream of the air flow in the cooler 4. Generally, the surface of the fins upstream of the air flow in the cooler has a high mass transfer rate and is an area where frost is likely to grow. Therefore, the temperature of the return pipe 58 increases downstream due to heating in the heat exchange unit 57. Therefore, by arranging the downstream part of the return pipe 58 where the temperature has increased close to the fins upstream of the air flow in the cooler 4, excessive frost growth can be suppressed, and the refrigerator 1 can be made less susceptible to deterioration in cooling performance due to blockage of the flow paths between the fins by frost.

[0072] Furthermore, the refrigerator 1 of this embodiment is provided with a heat insulating member 90 in the heat exchanger 57 (heating section) of the return pipe 58 (see FIG. 9). This makes it difficult for the heat from the heating section to be transferred to the low-temperature air inside the refrigerator, thereby suppressing an increase in the heat load inside the refrigerator, resulting in the refrigerator 1 having high energy-saving performance.

[0073] The refrigerator 1 of this embodiment also includes an internal fan 9 that generates an airflow within the storage compartment 3 formed in the insulated box 10, an air passage (air supply duct 20 and outlets 21a, 21b, 21c, and 21d) that sends air to the storage compartment 3 by driving the internal fan 9, a return opening 22 that returns air from the storage compartment 3 to the cooler compartment 8, a drain outlet 31 provided in the gutter 30, a drain pipe 32 connected to the drain outlet 31, and an evaporator tray 42 connected to the drain pipe 32. The drain outlet 31 is located downstream of the air inlet surface 4a of the cooler 4 and upstream (on the suction side) of the internal fan 9. This makes it difficult for moisture-laden air to flow into the storage compartment 3 from outside the refrigerator, even if a gap is created between the door 2 and the insulated box 10 by a user pinching food or the like, resulting in the refrigerator 1 being less susceptible to frost or condensation within the storage compartment 3. The reason for this is explained below.

[0074] Generally, when a fan disposed in an air passage is driven, the upstream side (intake side) of the fan becomes negative pressure relative to the downstream side (discharge side) of the fan. In the refrigerator 1 of this embodiment, the drain outlet 31 is disposed in an area downstream of the air inlet surface 4a of the cooler 4 and upstream (intake side) of the internal fan 9, and when the internal fan 9 is driven, the drain outlet 31 opens to an area that becomes negative pressure upstream of the internal fan 9. As a result, if a gap is formed between the door 2 and the insulated box body 10, air flows from outside the refrigerator through the drain pipe 32 and the drain outlet 31 into the cooler chamber 8, which becomes negative pressure, and from the storage chamber 3, which is downstream of the internal fan 9 (discharge side) and becomes positive pressure relative to atmospheric pressure, through the gap in the door 2. This makes it difficult for air containing a lot of moisture to flow into the storage chamber 3 from outside, resulting in the refrigerator 1 being less susceptible to frost or condensation in the storage chamber 3.

[0075] In addition, the refrigerator 1 of this embodiment is equipped with a radiator 50 (condenser), a compressor 24, an evaporator tray 42, and an external fan 29 in a machine room 25 provided at the bottom outside the insulated box body 10, and is configured so that the external fan 29 draws in and exhausts air from an intake port 27 and an exhaust port 28 provided on the front side of the machine room 25 to cool the radiator 50 and the compressor 24, and a drain outlet 31 is arranged downstream of the external fan 29. As a result, a positive pressure is created near the evaporator dish 42 by driving the external blower 29, so even if a gap is created between the door 2 and the insulated box body 10 by the user pinching food or the like, air will flow into the cooler chamber 8 from outside the cabinet via the drain pipe 32 and drain outlet 31, and a flow will be created in which air will flow out from the storage chamber 3 downstream (discharge side) of the internal fan 9 through the gap in the door 2, making it difficult for air containing a lot of moisture to flow into the storage chamber 3 from outside the cabinet, resulting in a refrigerator 1 in which frost and condensation are less likely to occur inside the storage chamber 3.

[0076] The refrigerator 1 of this embodiment includes a cooler 4, a storage compartment 3 maintained at a refrigerated temperature range, an internal fan 9 that creates an airflow within the storage compartment 3, a door 2 that can close the front opening of the storage compartment 3, a fixed or removable shelf (shelf 34b) disposed within the storage compartment 3, a food placement surface 34c, and a cooler compartment 8 disposed to include an area substantially directly below the placement surface 34c, and is also equipped with a temperature compensation means that raises the temperature of the placement surface 34c. This makes it possible to provide a highly reliable refrigerator 1 that prevents food stored in the storage compartment 3 maintained at a refrigerated temperature range from freezing. The reason for this will be explained below.

[0077] Generally, even when cooling a storage compartment in the refrigeration temperature range, the cooler temperature must be below zero to sufficiently cool the storage compartment, which results in a temperature inside the cooler compartment 8 also being below zero. Meanwhile, various foods may be stored on the food placement surface formed at the top of the cooler compartment. In this case, if the food on the placement surface is highly insulating (has low thermal conductivity) (e.g., bread), the temperature near the underside of the food (the surface in contact with the placement surface) may drop, resulting in freezing even when the storage compartment temperature is the same as the refrigerator compartment temperature. Potential solutions to this problem include improving insulation by placing a highly insulating insulating material between the cooler compartment and the placement surface or by increasing the thickness of the insulating material. However, even if the insulation is improved, sufficient effect may not be obtained when insulating food is placed on the placement surface, and the food may freeze. Therefore, the refrigerator 1 of this embodiment is equipped with a means (temperature compensation means) for raising the temperature of the food placement surface 34c (top surface of shelf 34b) (see Figure 12), making it a highly reliable refrigerator 1 that prevents food stored in storage compartment 3, which is in the refrigerated temperature range, from freezing.

[0078] Furthermore, the refrigerator 1 of this embodiment operates as a temperature compensation means by driving the internal fan 9 to send air into the storage compartment 3 when no refrigerant is supplied to the cooler 4 (see FIG. 12). As a result, the temperature of the cooler 4, which is no longer supplied with refrigerant, rises, which in turn raises the temperature of the cooler compartment 8, making it difficult for the food placement surface 34c to be cooled from below. This effectively raises the temperature of the food placement surface 34c, preventing the food from freezing.

[0079] Further, the refrigerator 1 of the present embodiment arranges a flow path 76 between the cooler chamber 8 and the food placement surface 34c as temperature compensation means (see FIG. 7), and drives the internal fan 9 to blow air into the storage chamber 3 in a state where refrigerant is not supplied to the cooler 4 (see FIG. 12). Thereby, in a state where the internal fan 9 is driven with the refrigerant supplied to the cooler 4, an air flow is generated in the flow path 76, so that cooling by heat conduction from the cooler chamber 8 is alleviated. Further, in a state where no refrigerant is supplied to the cooler 4, since the airflow with an increased temperature flows through the flow path 76, the temperature of the food placement surface 34c can be effectively raised. Therefore, an operation with a lower risk of food freezing can be implemented.

[0080] Further, the refrigerator 1 of the present embodiment sets the gap dimension L1 of the flow path R1 formed behind the placement surface 34c and the gap dimension L2 of the flow path R2 formed in front of the placement surface 34c so as to satisfy L1 < L2 (see FIG. 7). Thereby, the main flow of the airflow flowing in the storage chamber 3 can be made to flow toward the door 2 side in front of the placement surface 34c. Conversely, if the main flow is made to flow through the flow path R1 behind the placement surface 34c, the region close to the door 2 where the temperature easily rises due to heat intrusion cannot be cooled well. Therefore, by adopting the above configuration, the entire storage chamber 3 can be cooled well.

[0081] Further, the refrigerator 1 of the present embodiment sets the gap dimension L1 of the flow path R1 formed behind the food placement surface 34c and the gap dimension L3 of the flow path 76 formed below the food placement surface 34c so as to satisfy L1 < L3. Thereby, since the flow path R1 becomes narrower than the flow path 76, excessive airflow does not flow through the flow path 76, and the entire storage chamber 3 is easily cooled well.

[0082] Furthermore, the refrigerator 1 of this embodiment is configured such that the storage compartment 3 extends from above the cooler compartment 8 to the front, the return opening 22 that returns the air from the storage compartment 3 to the cooler compartment 8 is open forward, and a directing means is provided that directs the air so that it has a velocity component toward the upper surface of the cooler compartment 8. For example, the directing means is configured such that the relationship between the front opening dimension (vertical opening dimension) L4 of the return opening 22 and the depth opening dimension (horizontal opening dimension) L5 is L4>L5 (see FIG. 7). This allows the air that has flowed through the storage compartment 3 and has increased in temperature to flow along the upper surface of the cooler compartment 8, making it difficult for the temperature of the upper food placement surface 34c to decrease.

[0083] Furthermore, in the refrigerator 1 of this embodiment, the cooler compartment 8 is provided with a bypass flow path 77 on the upper side of the cooler 4 that bypasses the cooler 4 (see FIG. 7). This allows a portion of the air that has flowed through the storage compartment 3 and has increased in temperature to flow through the bypass flow path 77, making it more difficult for the temperature of the upper food placement surface 34c to decrease.

[0084] Furthermore, the refrigerator 1 of this embodiment is equipped with a temperature estimation means (storage compartment temperature sensor 45) that estimates the temperature of food in the storage compartment 3, and when the temperature estimation means estimates a drop in food temperature, the temperature compensation means raises the temperature of the food placement surface 34c (see the air blowing operation in FIG. 12). This makes it possible to more reliably prevent food from freezing without waste.

[0085] Furthermore, in the refrigerator 1 of this embodiment, the storage compartment temperature sensor 45 is disposed in the storage compartment 3 formed above the placing surface 34c, which makes it possible to more reliably estimate the risk of food freezing.

[0086] The refrigerator 1 of this embodiment also includes a cooling unit 250 that is provided inside the refrigerator 1 relative to the inner box 18 of the insulated box body 10 that includes the thermal insulation material 5. The cooling unit 250 includes a cooler 4, an internal fan 9, and a housing 67. The cooler 4 and the internal fan 9 are housed in the housing 67. This unitization facilitates assembly work into the refrigerator 1.

[0087] Furthermore, in the refrigerator 1 of this embodiment, the cooling unit 250 has a return pipe 58 connected to the suction side of the compressor 24 and a capillary tube 53 connected to the upstream side of the cooler 4. The return pipe 58 and the capillary tube 53 both pass through through holes 18z, 5z provided in the inner box 18 and the thermal insulation material 5. This makes it possible to prevent condensation from occurring in the gap between the inner box 18 and the thermal insulation material 5.

[0088] Moreover, in the refrigerator 1 of this embodiment, the cooling unit 250 has a shell-shaped gas-liquid separator 54 connected to the downstream side of the cooler 4, and a heater 54a installed in the gas-liquid separator 54. This makes it possible to suppress condensation on the gas-liquid separator 54.

[0089] The refrigerator 1 of this embodiment also includes a gutter 30 provided below the cooler 4, and a drain pipe 32 connected to the gutter 30. A part of the gutter 30 or the drain pipe 32 passes through through holes 18v, 5v provided in the inner box 18 and the thermal insulation material 5. The upstream end of the drain pipe 32 communicates with the space on the suction side of the internal fan 9, and the downstream end of the drain pipe 32 communicates with the machine room 25 in which the compressor 24 is provided. This makes it difficult for moist air to enter the storage chamber 3, even if a gap is formed between the door 2 and the thermally insulated box body 10, and prevents condensation from forming on the inner box 18.

[0090] The present invention is not limited to the above-described embodiment and includes various modifications. For example, although the refrigerator of this embodiment has one storage compartment in the refrigerated temperature range, the configuration of the present invention can be applied to a refrigerator having multiple storage compartments in the refrigerated temperature range, or to a storage compartment in the refrigerated temperature range of a refrigerator having a storage compartment in the freezer temperature range and a storage compartment in the refrigerated temperature range, or when setting the refrigerated temperature of a storage compartment that can be switched between the refrigerated temperature range and the freezer temperature range. Furthermore, an electric heater may be used as a temperature compensation means to more reliably prevent food from freezing. In other words, the above-described embodiment has been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to a refrigerator having all of the described configurations.

[0091] Fig. 14 is a top view of refrigerator 1 according to this embodiment with top plate 12 removed. Fig. 15 is a front view of door sensor 96. As shown in FIG. 14 , main wiring 98, which is disposed within, for example, the storage compartment 3 and extends from a control system board, is guided between the top plate 12 and the ceiling panel 13. This main wiring 98 passes through a hole (not shown) provided in the wall of the storage compartment 3 to reach between the heat insulating material 5 and the outer panel 11, then extends upward while crawling through the space between them, and is guided between the top plate 12 and the ceiling panel 13. The main wiring 98 is also connected to an interior light board 97 disposed at the front center of the ceiling panel 13. Relay wires 94 (94L, 94R) that transmit signals to the main wiring 98 are connected to the interior light board 97. The main wiring 98 is also used to exchange signals with the interior light board 97 as well as with the relay wires 94. However, if only the detection of the opening and closing of the door 2 is concerned, it is not necessary to connect the main wiring 98 and the relay wire 94 via the interior light board 97; they may be connected directly.

[0092] As shown in FIG. 15, a door sensor 96 is disposed on the front edge of the ceiling panel 13. The door sensor 96 includes hall sensors 961, 962 that detect whether the door 2 is open or closed, and a terminal 963 (see FIG. 16, described later) that outputs signals from the hall sensors 961, 962. The relay wire 94 is connected to the terminal 963. The door sensor 96 can be disposed on the non-hinge side of either of the left and right end regions 96L, 96R on the front edge of the ceiling panel 13. In this embodiment, the pivotable door 2 has a hinge 95R disposed on the right end, which serves as the pivot axis, and therefore the door sensor 96 is disposed in the left end region 96L, which is the non-hinge side. The door 2 is equipped with a permanent magnet 2M (see FIG. 16, described later) on the non-hinge end, and when this magnet approaches the hall sensor, the door sensor 96 detects that the door is closed. In this way, regardless of whether the refrigerator 1 is fitted with a door 2 that opens to the right or left, the door sensor 96 can be fitted on the opposite side to the hinge, making it easy to detect whether the door 2 is open or closed.

[0093] Furthermore, the door sensor 96 uses, for example, one of two Hall sensors 961, 962 arranged side by side on the opposite side to the hinge. Fig. 16 is a schematic diagram of a right-swinging door with a hinge 95R on the right side. Fig. 17 is a schematic diagram of a left-swinging door with a hinge 95L on the left side. Note that the main wiring 98 and relay wiring 94 are each made up of multiple wires bundled together, and in order to illustrate each wire, their widths are drawn significantly exaggerated from their actual dimensions.

[0094] The terminal 963 is a terminal with at least two pins corresponding to the signals of the Hall sensors 961 and 962. Four pins are depicted in Fig. 16. In the right-hand opening example in Fig. 16, in order to use only the signal of the Hall sensor 961 on the anti-hinge side out of the two Hall sensors 961 and 962, the relay line 94L includes a wiring 941L connected to the pin corresponding to the Hall sensor 961 on the anti-hinge side, but does not include a wiring 941R connected to the pin corresponding to the Hall sensor 962 on the hinge side.

[0095] On the other hand, in the left-hand opening example in Figure 17, in order to use only the signal from the Hall sensor 962 on the anti-hinge side of the two Hall sensors 961, 962, the relay line 94R is provided with wiring 941R connected to the pin corresponding to the Hall sensor 962 on the anti-hinge side, but does not have wiring 941L connected to the pin corresponding to the Hall sensor 961 on the hinge side.

[0096] In this way, only one type of main wiring 98 is used, running over a long distance between the insulation 5 and the outer panel 11, while two different types of relay wires 94 are used. The relay wires 94 can be replaced simply by removing the top plate 12, but the main wiring 98 requires removal of the outer panel 11, making replacement difficult. For this reason, by using one type of main wiring 98 in common and using different relay wires 94, it becomes easier to correct incorrect assembly.

[0097] The refrigerator 1 of this embodiment is provided with a control panel (not shown) inside the storage compartment 3. By operating the control panel, the user can change various settings, such as the temperature setting of the storage compartment 3. Since the refrigerator 1 has only one storage compartment, the control panel of this embodiment is provided with, for example, only two operation buttons.

[0098] A service person may perform maintenance or repairs on the refrigerator 1. Some models of refrigerator 1 require a specific command to be entered into a control panel to start a service mode that is convenient for the service person to provide service. Preparing such commands for the refrigerator 1 of this embodiment may result in commands that are very complicated due to the limited number of buttons, or may result in commands that are so simple that the user may accidentally enter the specific command.

[0099] For this reason, in the refrigerator 1 of this embodiment, the condition for starting the service mode is set to "operate the control panel while the door sensor 96 detects that the door 2 is closed." In this way, the start condition includes a condition other than the control panel operation, and an action that the user would not normally perform, thereby eliminating the above-mentioned inconvenience.

[0100] Specifically, a service person prepares a permanent magnet separate from the permanent magnet 2M on the door 2, and with the door 2 open, brings the permanent magnet close to whichever of the hall sensors 961, 962 of the door sensor 96 is being used. This allows the door sensor 96 to (falsely) detect that the door 2 is closed, even though the door 2 is actually open. Since the control panel is located inside the storage compartment 3, it is unlikely that the control panel will be operated with the door 2 closed in normal refrigerator usage. This prevents the user from unintentionally starting the service mode.

[0101] Such a condition that "in refrigerator 1 having a control panel inside storage compartment 3, the condition for starting the service mode is to input a predetermined command into the control panel while door sensor 96 of door 2 covering storage compartment 3 detects that it is closed" is particularly effective when the number of buttons on the control panel is small, for example, three or less.

[0102] FIG. 18 is a rear view of the refrigerator according to this embodiment with outer panel 11 removed. As shown in FIG. 18 , when outer panel 11 of refrigerator 1 is removed, thermal insulation 5 is exposed. Thermal insulation 5 is divided into thermal insulation 5a installed on the ceiling surface, thermal insulation 5b installed in the center of the back surface, thermal insulation 5c installed in the lower back surface, thermal insulation 5d installed on the left side, and thermal insulation 5e installed on the right side. Seams 501 between thermal insulation 5a-5e are covered with metal tape, such as aluminum tape 200, to bond the thermal insulation 5a-5e together. Since aluminum tape, which is highly effective in suppressing water vapor transmission, covers and bonds seams 501, water vapor that penetrates outside of thermal insulation 5 can be prevented from moving to the lower temperature inside of the refrigerator, thereby preventing condensation. Main wiring 98, which runs from the ceiling surface to machine room 25, is also covered with aluminum tape 200, which reduces the likelihood of condensation around main wiring 98.

[0103] Furthermore, on the inner surface side (thermal insulation material 5 side) of the outer plate 11, the wall surface heat dissipation piping 51, which runs in a zigzag pattern along the back surface, is fixed by a metal tape, for example, an aluminum tape 201, which is attached to the wall surface heat dissipation piping 51 along the wall surface heat dissipation piping 51 (the edges of the aluminum tape 201 are drawn with short dashed lines). The width of this aluminum tape 201 is greater than the width of the heat dissipation piping 51. By fixing the wall surface heat dissipation piping 51 to the outer plate 11 with a tape made of aluminum, a metal with high thermal conductivity, heat is efficiently transferred from the wall surface heat dissipation piping 51 to the outer plate 11 via the aluminum, improving heat dissipation performance. Furthermore, the aluminum tape 200 and the aluminum tape 201 are arranged so that they partially overlap, and when the outer plate 11 is attached, the aluminum tape 200 and the aluminum tape 201 are partially in contact with each other. By arranging the aluminum tape 200 and the aluminum tape 201 in this manner, the heat released from the wall surface heat dissipation piping 51 flows through the aluminum tape 201 and is transferred to the aluminum tape 200, thereby effectively heating the joints 501 between the heat insulating materials 5a to 5e and the area around the main wiring 98. This makes it less likely that condensation will form around the joints 501 and the main wiring 98.

[0104] Grooves (not shown) are formed in the heat insulating material 5 at a position opposite the wall surface heat radiation pipe 51 fixed to the outer plate 11 and at a position where the main wiring 98 is installed, and when the outer plate 11 is attached, the wall surface heat radiation pipe 51 and the main wiring 98 are stored in the grooves. This prevents the outer plate 11 and the heat insulating material 5 from being deformed when the outer plate 11 is attached.

[0105] The present application encompasses the following technical idea. [Appendix 1-1] A refrigerator comprising a cooler, a storage compartment in the refrigerated temperature range, an internal fan that creates an airflow within the storage compartment, a door that can close the front opening of the storage compartment, a fixed shelf or a removable shelf arranged within the storage compartment, a food placement surface, and a cooler compartment that houses the cooler and is arranged including an area approximately directly below the placement surface, and is also equipped with temperature compensation means that raises the temperature of the placement surface. [Appendix 1-2] The refrigerator according to appended note 1-1, wherein, as the temperature compensation means, air is blown into the storage chamber in a state where no refrigerant is supplied to the cooler. [Appended note 1-3] The refrigerator according to appended note 1-1, wherein, as the temperature compensation means, a flow path is arranged between the cooler chamber and the placement surface, and air is blown into the storage chamber in a state where no refrigerant is supplied to the cooler. [Appended note 1-4] The refrigerator according to appended note 1-3, wherein the clearance dimension L1 of the flow path formed behind the placement surface and the clearance dimension L2 of the flow path formed in front of the placement surface satisfy L1 < L2. [Appended note 1-5] The refrigerator according to appended note 1-3 or appended note 1-4, wherein the clearance dimension L1 of the flow path formed behind the placement surface and the clearance dimension L3 of the flow path formed below the placement surface satisfy L1 < L3. [Appended note 1-6] The refrigerator according to appended note 1-2, wherein the storage chamber is formed from above the cooler chamber to the front, a return opening for returning the air in the storage chamber to the cooler chamber opens forward, and a directing means is provided which is directed so as to have a velocity component toward the upper surface side of the cooler chamber. [Appended note 1-7] The refrigerator according to appended note 1-2, wherein the cooler chamber is provided with a bypass flow path that bypasses the cooler on the upper surface side of the cooler. [Appended note 1-8] The refrigerator is provided with temperature estimation means for estimating the food temperature in the storage chamber, The refrigerator according to appended note 1-1, wherein when the decrease in the food temperature is estimated based on the temperature estimation means, the temperature of the placement surface is raised by the temperature compensation means. [Appended note 1-9] The refrigerator according to appended note 1-8, wherein, as the temperature estimation means, a temperature sensor is arranged in the storage chamber formed above the placement surface. [Appended note 1-10] The cooling unit is provided on the inside of the inner box of the heat-insulating box body including the heat insulating material, the cooling unit includes the cooler, a fan, and a housing; The refrigerator according to appendix 1-1, wherein the cooler and the internal fan are housed in the housing. [Appendix 1-11] the cooling unit has an outlet pipe connected to a suction side of a compressor and a capillary tube connected to an upstream side of the cooler, The refrigerator described in Appendix 1-10, wherein both the outlet pipe and the capillary tube pass through first through holes provided in the inner box and the heat insulating material. [Appendix 1-12] The refrigerator described in Appendix 1-10, characterized in that the cooling unit has a shell-shaped gas-liquid separator connected downstream of the cooler, and a heater installed in the gas-liquid separator. [Appendix 1-13] a gutter provided below the cooler; a drainage pipe connected to the gutter, A part of the gutter or the drain pipe passes through a second through hole provided in the inner box and the thermal insulation material, The upstream end of the drain pipe communicates with a space on the suction side of the fan, The refrigerator described in Appendix 1-10, wherein the downstream end of the drain pipe is connected to a machine room in which a compressor is installed. [Appendix 1-14] a gutter provided at a lower portion of the cooler; a return opening communicating the storage chamber with a cooler chamber that houses the cooler; The refrigerator described in Appendix 1-1, characterized in that at least a portion of the gutter is located between the cooler and the return opening and has a gap L9 of 1 mm or more between the cooler and the gutter. [Explanation of symbols]

[0106] 1 refrigerator 2 doors 3. Storage Room 4 Cooler 5, 5a, 5b, 5c, 5d, 5e Insulation 5v through hole 5z through hole 6 Second door insulation 7 Door first insulation 8 Cooler room 9. In-cabinet fan (in-cabinet blower) 10 Insulated box 11 Outer Panel 11v through hole 11z through hole 12 Top Plate 13 Ceiling Panel 14 Front Panel 15 Door inner surface material 16a Upper surface member 16b Bottom member 17 Leading edge steel plate 18 Inner box 18 Through holes 18z through hole 19 Sealing material 20 Air duct (airway) 21a, 21b, 21c, 21d Discharge port (air path) 22 Return opening 24 Compressor 25 Machine room 27 Suction port 28 Exhaust port 29 External blower 30 Gutter 31 Drain 32 Drain pipe 33 Shelf 34a, 34b shelves 34c Placement surface 35 Container 45 Storage compartment temperature sensor 50 Heat sink (heat radiation piping) 51 Wall heat radiation piping (heat radiation piping, heating piping) 52 Condensation prevention piping (heat dissipation piping) 53 Capillary tube (heating piping) 54 Gas-liquid separator 54a Heater 55 Dryer 57 Heat exchange section (heating section) 58 Return pipe (outlet pipe) 59 Discharge piping 60 Electric heater 66 Gas-liquid separator storage space 67 Containment Unit 70 Circuit Board Storage Box 76 Flow path 77 Bypass flow path 80 Communication hole (gap) 90 Heat insulating materials 94R relay line 94L trunk line 941R door opening / closing signal 942L door opening / closing signal 95R,95L hinge 96 Door Sensor 961 Hall Sensor 962 Hall Sensor 963 Output section 964 Output Section 98 Main wiring 150 Refrigeration Cycle 151 Connection piping (heat dissipation piping) 200 Aluminum Tape (another metal tape) 201 Aluminum tape (metal tape) 250 Cooling Unit 501 Seam 961,962 Hall sensor (sensor) L10 length (length passing through the gap) L20 length (upstream length of gap outlet pipe)

Claims

1. The air conditioner includes a heat insulating box body formed by including a heat insulating material and a refrigeration cycle in which a refrigerant circulates, the refrigeration cycle includes a cooler housed in the thermally insulated box, a compressor housed outside the thermally insulated box, and an outlet pipe connecting a downstream side of the cooler and an upstream side of the compressor, The outlet piping is led to the outside of the insulated box through a gap in the insulated box, air is present in the gap, and a heating unit is disposed to heat a portion of the outlet piping that passes through the gap and a portion upstream of this, or a portion of the outlet piping that is upstream of the portion that passes through the gap, and the piping temperature of the outlet piping upstream of the gap reaches or exceeds the dew point.

2. A refrigerator as described in Claim 1, characterized in that the gap is arranged in the insulated box body having the insulation material that has been foam-molded or processed in advance.

3. The refrigeration cycle includes a heat radiation pipe as a heating pipe through which a high-temperature, high-pressure refrigerant discharged from the compressor flows, and a capillary tube that reduces the pressure of the high-temperature, high-pressure refrigerant to a low-temperature, low-pressure refrigerant, the heating unit is a heat exchange unit in which the heating pipe is in thermal contact with the outlet pipe, 3. The refrigerator according to claim 2, wherein the heat exchanger has the capillary tube in thermal contact with the outlet pipe.

4. The refrigerator according to claim 3, characterized in that the relationship between a length L10 of the contact portion between the outlet pipe and the capillary tube that passes through the gap and a length L20 of the gap on the upstream side of the outlet pipe is L10<L20.

5. a gutter provided at a lower portion of the cooler; 2. The refrigerator according to claim 1, wherein the outlet pipe is installed in an upper projected area of ​​the trough.

6. 6. The refrigerator according to claim 5, wherein the heating unit is disposed in a region formed between the cooler and the trough.

7. A heat-insulating box body formed with a heat insulating material and a refrigeration cycle in which a refrigerant circulates, The refrigeration cycle includes a cooler housed in the heat-insulating box, a compressor housed outside the heat-insulating box, an outlet pipe connecting a downstream side of the cooler and an upstream side of the compressor, and a heating pipe through which a high-temperature refrigerant discharged from the compressor flows, the outlet pipe is led to the outside of the insulating box through a gap in the insulating box, air is present in the gap, and a heating unit is disposed to heat a portion of the outlet pipe that passes through the gap and a portion upstream of the portion, or a portion of the outlet pipe that is upstream of the portion that passes through the gap; the heating unit is a heat exchange unit in which the heating pipe is in thermal contact with the outlet pipe, The refrigeration cycle includes, as the heating pipe, a heat radiation pipe through which a high-temperature, high-pressure refrigerant flows, and a capillary tube that reduces the pressure of the high-temperature, high-pressure refrigerant to a low-temperature, low-pressure refrigerant; the heat exchange unit brings the capillary tube into thermal contact with the outlet pipe; The refrigerator is characterized in that the pipes forming the heat exchange unit are arranged in a plurality of rows below the cooler, and the row of the outlet pipes forming the heat exchange unit on the downstream side of the refrigerant flow is located close to the fins on the upstream side of the air flow of the cooler.

8. 4. The refrigerator according to claim 3, wherein a heat insulating member is disposed in the heat exchange section.

9. 6. The refrigerator according to claim 5, further comprising: an internal fan that forms an airflow in a storage compartment formed in the insulated box; an air passage that sends air to the storage compartment by driving the internal fan; a return opening that returns air from the storage compartment to the cooler compartment; a drain outlet provided in the gutter; a drain pipe connected to the drain outlet; and an evaporator tray connected to the drain pipe, wherein the drain outlet is located in a region downstream of an air inlet surface of the cooler and upstream of the internal fan.

10. A heat-insulating box formed with a heat insulating material and a refrigeration cycle in which a refrigerant circulates, The refrigeration cycle includes a cooler housed within the thermally insulated box, a compressor housed outside the thermally insulated box, an outlet pipe connecting the downstream side of the cooler and the upstream side of the compressor, and a heating pipe through which a high-temperature refrigerant discharged from the compressor flows and which is laid on the outside of the thermally insulated box, a metal tape attached on the heating pipe along the heating pipe; The insulating box includes a plurality of preformed insulating materials and another metal tape for joining the seams of the insulating materials adjacent to each other, The refrigerator is characterized in that the metal tape and the other metal tape are in at least partial contact with each other.

11. A heat-insulating box body formed with a heat insulating material and a refrigeration cycle in which a refrigerant circulates, The refrigeration cycle includes a cooler housed within the thermally insulated box, a compressor housed outside the thermally insulated box, an outlet pipe connecting the downstream side of the cooler and the upstream side of the compressor, and a heating pipe through which a high-temperature refrigerant discharged from the compressor flows and which is laid on the outside of the thermally insulated box, the outlet pipe is led to the outside of the insulating box through a gap in the insulating box, air is present in the gap, and a heating unit is disposed to heat a portion of the outlet pipe that passes through the gap and a portion upstream of the portion, or a portion of the outlet pipe that is upstream of the portion that passes through the gap; a metal tape attached on the heating pipe along the heating pipe; The insulating box includes a plurality of preformed insulating materials and another metal tape for joining the seams of the insulating materials adjacent to each other, The refrigerator is characterized in that the metal tape and the other metal tape are in at least partial contact with each other.

12. A device comprising an insulated box body formed with a heat insulating material, a refrigeration cycle in which a refrigerant circulates, a door that opens and closes the opening of the insulated box body and rotates around a hinge, and a door sensor that detects the opening and closing of the door and has two sensors arranged side by side in the left-right direction, The door sensor detects whether the door is open or closed using the sensor farther from the hinge out of the two sensors; a control panel disposed in a storage compartment at the back of the opening; The refrigerator is characterized in that a service mode can be executed by performing a predetermined operation on the control panel when the door sensor detects that the door is closed.

13. A heat-insulating box body formed with a heat insulating material and a refrigeration cycle in which a refrigerant circulates, the refrigeration cycle includes a cooler housed in the thermally insulated box, a compressor housed outside the thermally insulated box, and an outlet pipe connecting a downstream side of the cooler and an upstream side of the compressor, the outlet pipe is led to the outside of the insulating box through a gap in the insulating box, air is present in the gap, and a heating unit is disposed to heat a portion of the outlet pipe that passes through the gap and a portion upstream of the portion, or a portion of the outlet pipe that is upstream of the portion that passes through the gap; a door that opens and closes the opening of the heat-insulating box and rotates around a hinge; a door sensor in which two sensors for detecting the opening and closing of the door are arranged side by side in the left-right direction, The door sensor detects whether the door is open or closed using the sensor farther from the hinge out of the two sensors; a control panel disposed in a storage compartment at the back of the opening; The refrigerator is characterized in that a service mode can be executed by performing a predetermined operation on the control panel when the door sensor detects that the door is closed.

Images