JP2013057415A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce power consumption by eliminating the shortage of a refrigerant caused by a residual refrigerant in a pipe generating in switching refrigerant pipes, and to reduce refrigerant flowing noise generated when the refrigerant passes through a switch valve.SOLUTION: In this refrigerator having a refrigerant circuit successively connecting a compressor, a heat radiating means, a pressure reducing means and a cooler, the heat radiating means includes a first heat radiating means radiating heat to the outside of the refrigerator, and a second heat radiating means for heating a partitioning section, and further includes a first refrigerant flow channel for allowing the refrigerant compressed by the compressor to flow to the first heat radiating means and the second heat radiating means, a second refrigerant flow channel for making the refrigerant bypass the first refrigerant flow channel after circulating to the first heat radiating means, and a flow channel switching means for switching the first refrigerant flow channel and the second refrigerant flow channel. Internal volumes of the first refrigerant flow channel and the second refrigerant flow channel are smaller than an internal volume of the first heat radiating means.

Description

  The present invention relates to a refrigerator.

  As a conventional refrigerator, a refrigerator in which a dew condensation prevention pipe is arranged at an opening edge of a storage room is known. The heat insulation box constituting the refrigerator body is provided with a plurality of storage chambers, and a heat insulating door for opening and closing the opening in front of the storage chamber is attached. The contact portion between the opening and the door, that is, the opening edge portion of the storage chamber is cooled by the cool air inside the cabinet, and the surface of the contact portion is likely to generate condensation due to a temperature difference with the outside air. In order to suppress this phenomenon of dew condensation, a dew condensation prevention pipe using a heat radiating pipe of the refrigeration cycle is embedded in the opening edge of the storage chamber.

  In the refrigerator described in Patent Document 1, a switching valve is provided in the middle of a plurality of divided condensers to efficiently heat the condensation prevention pipe, and further, bypass the condensation prevention pipe without causing a refrigerant shortage phenomenon in the refrigeration cycle. Means are provided to reduce power consumption.

  In addition, a configuration is described in which a switching valve is used to switch between a heating mode in which refrigerant flows through the dew condensation prevention pipe and a mode in which refrigerant flows through the dew condensation prevention pipe. When the circulation of the refrigerant to the dew condensation prevention pipe is stopped, the refrigerant remaining in the dew condensation prevention pipe causes a shortage of refrigerant as the whole refrigeration cycle. As means for avoiding this, in Patent Document 1, the condensation prevention pipe is connected between the compressor and the condenser, and the condensation prevention pipe is filled with the refrigerant in the gas phase region, thereby being confined in the condensation prevention pipe. Refrigerant amount is reduced.

JP 2009-174767 A

  In the refrigerator described in Patent Document 1, a compressor, a first condenser, a dew condensation prevention pipe, a second condenser, a throttle, and a cooler are connected in this order to constitute a refrigeration cycle. In the condensation prevention piping, in order to mainly use heat radiation in the gas phase region, the condensation prevention piping is provided between the first condenser and the second condenser. When the refrigerant gas discharged from the compressor passes through the first condenser, the dew condensation prevention pipe, and the second condenser, the refrigerant gas releases heat to the outside so that the superheated gas region (gas phase region) and the gas-liquid two-phase region. The phase changes in turn to the liquid phase region.

  The first condenser is a system for releasing heat to the outside air from the heat sink pipe provided on the refrigerator back side, and the second condenser is provided on the side of the refrigerator. In this configuration, for example, when a heating appliance (heating source) is placed near the side wall of the refrigerator where the second condenser is installed, the refrigerant in the second condenser absorbs external heat, The portion is vaporized to become gas (gas phase).

  The refrigerant flowing out of the second condenser flows into the cooler through the throttle, but the enthalpy difference at the cooler inlet / outlet becomes small, resulting in a decrease in heat absorption, resulting in deterioration of the cooling performance in the cabinet, and power consumption. (See FIG. 11).

  In patent document 1, the consideration regarding said subject is inadequate.

  Furthermore, although a switching valve is arranged between the first condenser and the second condenser, the state of the refrigerant inside the switching valve is in a gas phase region or a gas-liquid two-phase region. There is a risk that refrigerant flow noise will be generated when passing through.

  Further, the switching valve switches between the condensation prevention pipe and the pipe bypassing the condensation prevention pipe, but a certain amount of refrigerant leakage from the switching valve is allowed. For this reason, for example, when the switching valve is fixed to the dew condensation prevention piping side, the refrigerant stays on the bypass side of the dew condensation prevention piping, which may cause shortage of the refrigerant. In general, when the refrigerant stays in the piping in the refrigeration cycle, the refrigerant in the refrigeration cycle is recovered by switching to a fully closed state with a switching valve having a fully closed function on the compressor discharge side.

  However, in the case of the refrigeration cycle described in Patent Document 1, if the refrigerant staying in the dew condensation prevention pipe and the pipe bypassing it is collected every time it is switched by the switching device, the power consumption increases due to a reduction in the efficiency of the compressor. There is a risk that.

  Here, the upper limit of the amount of refrigerant sealed in a forced circulation type refrigerator using a combustible refrigerant gas is 100 g in Japan. The refrigerator in Japan has many electrical components and uses an electric heater (for example, a glass tube heater) at the time of defrosting. Therefore, the upper limit value of the refrigerant filling amount when using a flammable refrigerant is kept low.

  On the other hand, in European refrigerators, there are many cold convection types, and there are many products that defrost frost without using an electric heater, so the upper limit of the amount of refrigerant filled is higher than in Japan, and the European IEC standard is 150 g. Yes.

  In refrigerators with an internal volume of 400 to 500 L in Japan, the amount of refrigerant enclosed is about 80 to 90 g. Therefore, in order to eliminate the shortage of refrigerant in the refrigeration cycle for switching the condenser side, it is already possible to increase the amount of refrigerant enclosed. Since it is close to the upper limit value, it is not easy to eliminate the refrigerant shortage.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to solve the shortage of refrigerant due to the residual refrigerant in the pipe generated when switching the refrigerant pipe and to reduce the power consumption. And It is another object of the present invention to reduce refrigerant flow noise generated when refrigerant passes through the switching valve.

  In order to solve the above problems, for example, the configuration described in the scope of the claims is adopted. The present application includes a plurality of means for solving the above-described problems. For example, in a refrigerator having a refrigerant circuit in which a compressor, a heat radiating means, a pressure reducing means, and a cooler are sequentially connected, the heat radiating is performed. The means includes a first heat radiating means for radiating heat to the outside of the cabinet and a second heat radiating means for heating the partition, and the refrigerant compressed by the compressor is used as the first heat radiating means and the A first refrigerant flow path that flows to the second heat radiating means; a second refrigerant flow path that bypasses the first refrigerant flow path after circulating the refrigerant through the first heat radiating means; And a flow path switching means for switching the second refrigerant flow path, and the internal volume of the first refrigerant flow path and the second refrigerant flow path is the internal volume of the first heat dissipation means. It is characterized by being smaller than.

  ADVANTAGE OF THE INVENTION According to this invention, the refrigerant | coolant shortage by the residual refrigerant | coolant in the piping which generate | occur | produces when switching refrigerant piping can be eliminated, and reduction of power consumption can be aimed at. Further, it is possible to reduce the refrigerant flow noise generated when the refrigerant passes through the switching valve.

It is a front external view of the refrigerator which concerns on embodiment of this invention. It is a cross-sectional view in the refrigerator of the refrigerator according to the embodiment of the present invention. It is a block diagram of the refrigerating cycle of the refrigerator which concerns on embodiment of this invention. It is an arrangement drawing of a radiator of a refrigerator concerning an embodiment of the present invention. It is a cross-sectional schematic diagram of the partition wall of the refrigerator which concerns on embodiment of this invention. It is a schematic diagram which shows the internal structure of the machine room of the refrigerator which concerns on embodiment of this invention. It is an external view of the state which attached the machine room cover to the machine room of the refrigerator which concerns on embodiment of this invention. It is a figure explaining the control image in the case of switching dew condensation prevention piping. It is a time chart which shows an example of the cooling operation of the refrigerator which concerns on embodiment of this invention. It is the figure which represented typically the state of the refrigerant | coolant in heat radiator piping. It is the figure which represented typically the state of the refrigerant | coolant in the radiator piping which concerns on embodiment of this invention. It is a Mollier diagram showing the driving | running state of the refrigerator which concerns on embodiment of this invention. It is the figure which showed typically the state of the refrigerant | coolant inside a three-way valve. It is the figure which showed typically the state of the refrigerant | coolant inside a three-way valve. It is a block diagram of the refrigerating cycle of the refrigerator which concerns on other embodiment of this invention. It is a flowchart which shows an example of the cooling operation in other embodiment of FIG.

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

  FIG. 1 is a front external view of a refrigerator according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the refrigerator according to the embodiment of the present invention. As shown in FIG. 1, a refrigerator 1 according to this embodiment includes a refrigerator room 2, an ice making room 3, an upper freezer room 4, a lower freezer room 5, and a vegetable room 6 from above. The ice making chamber 3 and the upper freezing chamber 4 are arranged side by side. The refrigerating room 2 includes left and right refrigerating room doors 2a and 2b. The ice making room 3, the upper freezing room 4, the lower freezing room 5, and the vegetable room 6 are a pull-out ice making room door 3a and an upper freezing room door, respectively. 4a, a lower freezer compartment door 5a, and a vegetable compartment door 6a. Hereinafter, the refrigerator compartment doors 2a and 2b, the ice making compartment door 3a, the upper freezer compartment door 4a, the lower freezer compartment door 5a, and the vegetable compartment door 6a may be simply referred to as doors. Further, the refrigerator 1 notifies the user when a door sensor (not shown) that detects the open / closed state of each door and a state determined to be the door open state continue for a predetermined time, for example, 1 minute or more. Alarm (not shown), a temperature setting device (not shown) for setting the temperature of the refrigerator compartment 2 and the freezer compartment 5 and the like. A door hinge that rotatably fixes the doors 2 a and 2 b to the refrigerator 1 is provided at the upper part of the refrigerator, and the door hinge is covered with a door hinge cover 80. Condensation prevention pipes 43 are embedded in the respective opening edges of the storage chambers, that is, the partition walls 28, 29, and 40 having heat insulation properties shown in FIG. 2 (see FIGS. 4 and 5).

  In the refrigerator 1 of the present embodiment, the refrigerator compartment 2, the upper freezer compartment 4, and the ice making room 3 (see FIG. 1, the ice making room 3 is not shown in FIG. 2) are insulated from each other by the upper partition wall 28. The lower freezer compartment 5 and the vegetable compartment 6 are adiabatically separated by the lower partition wall 29. In addition, as shown in FIG. 2, a partition wall 40 is provided in the upper part of the lower freezer compartment 5. The partition wall 40 partitions the ice making chamber 3 and the upper freezing chamber 4 from the lower freezing chamber 5 in the vertical direction. In addition, a vertical partition (not shown) that partitions the ice making chamber 3 and the upper freezing chamber 4 in the left-right direction is provided on the upper portion of the partition wall 40.

  The partition wall 40 receives a seal member (not shown) provided on the storage chamber side surface of the lower freezer compartment door 5a together with the front surface of the partition wall 28 and the front surfaces of the left and right side walls, and is connected to the lower freezer compartment door 5a. Suppresses gas movement. Further, seal members (not shown) provided on the storage room side surfaces of the ice making door 3a and the upper freezing room door 4a are in contact with the partition wall 40, the vertical partition, the partition wall 28, and the front surfaces of the left and right side walls of the refrigerator 1. This suppresses the movement of gas between each storage chamber and each door (detailed structure will be described later).

  The ice making chamber 3, the upper freezing chamber 4, and the lower freezing chamber 5 are all in the freezing temperature zone, so that the partition wall 40 and the vertical partitioning portion are at least on the front side of the refrigerator in order to receive the seal member of each door. Good (see FIG. 2). That is, there may be a movement of gas between the storage chambers in the freezing temperature zone, and there may be a case where the heat insulation section is not provided. On the other hand, when the upper freezer compartment 4 is a temperature switching chamber, the partition wall 40 and the vertical partition section extend from the front side of the refrigerator 1 to the rear wall because it is necessary to perform heat insulation.

  The outside of the refrigerator 1 and the inside of the refrigerator are separated by a heat insulating box 10 formed by filling a foam heat insulating material. A plurality of vacuum heat insulating materials 25 are mounted on the heat insulating box 10 of the refrigerator 1. The refrigerator compartment 2 separates the refrigerator compartment 2 from the upper freezer compartment 4 and the ice making compartment 3 by a partition wall 28. A partition wall 29 separates the lower freezer compartment 5 from the vegetable compartment 6. A plurality of door pockets 32 are provided inside the doors 2a and 2b, and the refrigerator compartment 2 is partitioned into a plurality of storage spaces in the vertical direction by a plurality of shelves 36. A partition wall 40 is provided between the upper freezer compartment 4 and the lower freezer compartment 5.

  As shown in FIGS. 1 and 2, the ice making room 3, the upper freezing room 4, the lower freezing room 5, and the vegetable room 6 are integrated with doors 3a, 4a, 5a, 6a provided in front of the respective cooling rooms. Storage containers 3b, 4b, 5b, 6b are provided, respectively, and the storage containers 4b, 5b, 6b can be pulled out by pulling out the respective doors 4a, 5a, 6a to the front side. .

  Moreover, the humidity sensor 81 and the temperature sensor 82 for detecting the humidity and temperature outside the refrigerator are provided, for example, inside the door hinge cover 80 above the ceiling wall of the refrigerator 1. The reason why the humidity sensor 81 and the temperature sensor 82 are provided inside the door hinge cover 80 in this embodiment is to detect the ambient humidity and the ambient temperature by making it less likely to be directly affected by the temperature from the refrigerator 1 main body. In addition, although the installation location of the humidity sensor 81 and the temperature sensor 82 is not restricted to this, the place which can detect the ambient humidity and ambient temperature of the refrigerator 1 installation environment appropriately, without receiving the temperature influence from the refrigerator 1 main body directly. If it is.

  The cooler 7 is provided in a cooler storage chamber 8 provided substantially at the back of the lower freezer compartment 5, and is cooled by an internal fan 9 (a propeller fan as an example) provided above the cooler 7. The cold air heat-exchanged with the refrigeration room 7 is connected to the refrigeration room 2, the upper freezer compartment 4, the upper freezer compartment air duct 12, the lower freezer compartment air duct 13, and the ice making room air duct (not shown). It is sent to each storage room of the lower freezing room 5 and the ice making room 3.

  The air blowing to each storage room is controlled by opening and closing the refrigerator compartment damper 20 and the freezer compartment damper 34. Specifically, when the refrigerator compartment damper 20 is in the open state and the freezer compartment damper 34 is in the closed state, the cold air is sent to the refrigerator compartment 2 from the outlets 2c provided in multiple stages via the refrigerator compartment air duct 11. After the cooling of the refrigerator compartment 2 is finished, cold air flows into a refrigerator compartment return port (not shown) provided at the lower part of the refrigerator compartment 2 and then returned to the cooler 7. There are various methods for cooling the vegetable compartment 6, for example, a method of directly sending cold air to the vegetable compartment 6 after cooling the refrigerator compartment 2, or a cool air generated in the cooler 7 does not pass through the refrigerator compartment 2. Thus, a method of sending it alone to the vegetable compartment 6 can be considered. In this case, in order to control the cold air supplied to the vegetable compartment 6, a damper dedicated to the vegetable compartment is required. In the present application, any method may be used for supplying cold air to the vegetable compartment 6. In the example shown in FIG. 2, the cold air that has flowed into the vegetable compartment 6 passes from the vegetable compartment return outlet 18 a through the vegetable compartment return duct 18 from the vegetable compartment return port 6 d provided in front of the lower part of the partition wall 29. It flows into the cooler 7.

  The cool air sent into the freezer compartment cools the upper freezer compartment 4, the lower freezer compartment 5, and the ice making chamber 3, and then returns to the cooler 7 from the freezer compartment return port 17. A defrost heater 22 is provided at the lower part of the cooler 7, and the drain water generated at the time of defrosting once falls into the eaves 23 and is discharged to the evaporating dish 21 provided at the upper part of the compressor 24 through the drain hole 27. . A control board 33 which is a control device equipped with a memory and an interface circuit is disposed on the upper surface of the ceiling wall of the refrigerator 1, and the refrigeration cycle and the blower system are controlled according to the control board 33. The control board 33 is covered with a board cover 83.

  Next, FIG. 3 is a block diagram of the refrigeration cycle of the refrigerator according to the embodiment of the present invention. In the discharge side pipe 66 of the compressor 24, a first radiator 46 provided with a machine room fan 45 (external fan), second radiators 41a and 41b, and a third radiator 42 are sequentially arranged. Connected. The other end of the pipe 51 connected to the third radiator 42 is connected to the C side (inflow side) of the three-way valve 48 (flow path switching means). During the cooling operation, the three-way valve 48 branches in two directions, the cycle A side and the cycle B side, which are the outlet sides, and can flow in one direction, and if necessary, the cycle A side and the cycle B side. It is also possible to stop the refrigerant flow by closing both outlets. Furthermore, when the refrigerant is sealed in the refrigeration cycle, both the cycle A side and the cycle B side of the three-way valve 48 can be opened.

  A pipe 52 is connected to the A side of the three-way valve 48, and a fourth radiator 43, that is, a dew condensation prevention pipe is connected to the other end of the pipe 52. A pipe 53, that is, a dew condensation prevention pipe bypass pipe is connected to the B side of the three-way valve 48.

  The first radiator 46, the second radiators 41a and 41b, and the third radiator 42 provided between the compressor 24 and the three-way valve 48 are collectively used as a first radiator, and the compressor 24 discharges. From the outlet to the C side of the three-way valve 48 (three-way valve 48 inlet) is a refrigerant flow pipe a. The fourth radiator 43 is provided on the downstream side of the three-way valve 48, and the fourth radiator 43 side serves as the second radiator, and is connected to the A side (three-way valve 48 outlet) of the three-way valve 48. A merge pipe 56 (first refrigerant flow path) that merges with the other end of the outlet side pipe 54, and a merge pipe 56 (that merges with the other end of the pipe 53 connected to the B side (three-way valve 48 outlet) of the three-way valve 48. The second refrigerant channel) is defined as a refrigerant channel pipe b.

  A check valve 55 is provided between the fourth radiator 43 and the junction pipe 56. A pipe 57 is connected to the junction pipe 56, and a dryer 58 and a two-way valve 49 are provided in the middle of the pipe 57 in this order. A pipe 60 is connected to the other end of the two-way valve 49, and the throttle 61 and the cooler 7 provided with the internal fan 9 are connected in this order. A pipe 64 is connected to the outlet side of the cooler 7, and a heat exchanging portion 65 with the throttle 61 is provided in the middle, and the other end of the pipe 64 is connected to the suction side of the compressor 24. Since the pipe of the fourth radiator 43 is embedded in the partition walls 28, 29, and 40 (see FIG. 2), it is cooled by the influence from the freezing temperature zone. The three-way valve 48 switches the fourth radiator 43 (cycle A side) and the pipe 53 (cycle B side) at predetermined time intervals. When the refrigerant is flowing through the pipe 53 (cycle B side), since the refrigerant does not flow through the fourth radiator 43, the temperature of the fourth radiator 43 decreases due to the influence from the freezer compartment. Therefore, even though the three-way valve 48 is fixed to the pipe 53 (cycle B side), a part of the refrigerant flowing through the pipe 53 flows back to the fourth radiator 43 through the junction pipe 56, and the fourth When the refrigerant remains in the pipe of the radiator 43 and the operation is performed on the cycle B side, there is a possibility of causing a refrigerant shortage. Accordingly, a check valve 55 is provided between the fourth radiator 43 and the junction pipe 56 so that the refrigerant does not flow into the piping of the fourth radiator 43 when operating on the cycle B side. Yes.

  FIG. 4 is a layout diagram of the refrigerator heat radiator according to the embodiment of the present invention. FIG. 5 is a schematic cross-sectional view of the heat insulating partition wall of the refrigerator according to the embodiment of the present invention.

  The 1st heat radiator 46 is installed in the machine room 44 provided in the back side lower part of the refrigerator 1 (refer FIG. 6). The second radiators 41a and 41b are embedded in the side heat insulating walls of the refrigerator 1 (indicated by broken lines in FIG. 4), and the third radiator 42 is embedded in the rear heat insulating wall of the refrigerator 1 (in FIG. 4). (Dotted line) The second radiators 41 a and 41 b and the third radiator 42 are arranged so as to radiate heat in contact with or close to a metal outer plate that forms the appearance of the refrigerator 1. The fourth radiator 43, that is, the dew condensation prevention pipe is embedded in the partition walls 28, 29, and 40 that divide the storage chambers (shown by solid lines in FIG. 4).

  FIG. 5 is a schematic cross-sectional view of the partition walls 28, 29, and 40. The pipe of the fourth radiator 43 is provided so as to be in contact with or close to the partition cover 84 (as an example, a highly heat conductive metal plate) provided on the partition wall. When the temperature around the refrigerator is, for example, 30 ° C., the pipe temperature of the fourth radiator 43 during steady operation is about 33 ° C., and a freezing temperature zone (about −20 ° C. close to the partition walls 28, 29, 40 ( A large temperature difference is formed with respect to the ice making chamber 3, the upper freezing chamber 4, and the lower freezing chamber 5). Since the surface of the partition cover 84 and the surrounding air are cooled by the freezing temperature zone, the temperature decreases, and moisture in the air near the partition cover 84 may cause condensation on the surface of the partition cover 84. In order to avoid this, the refrigerant is passed through the fourth radiator 43 to heat the partition cover 84 (the heat flow indicated by reference numeral 86 in FIG. 5), but is released from the fourth radiator 43. The heat is also heated even in the freezing temperature zone room where the temperature difference is large (the heat flow indicated by reference numeral 85 in FIG. 5), resulting in deterioration in energy saving, that is, an increase in power consumption. Yes.

  FIG. 6 is a schematic diagram showing the internal structure of the machine room 44 of the refrigerator according to the embodiment of the present invention. FIG. 7 is an external view of a state in which a machine room cover 87 is attached to the machine room 44 of the refrigerator according to the embodiment of the present invention.

  In the machine room base 47 of the machine room 44, the first radiator 46, the machine room fan 45 (external fan), and the compressor 24 are arranged in this order from the windward side. An evaporating dish 21 for receiving drain water generated when the frost of the cooler 7 is thawed is provided on the upper portion of the compressor 24. Since the three-way valve 48 and the two-way valve 49 are respectively fixed to the fixture 50 in advance, the posture of the valve can be maintained almost vertically even after being connected to the pipe in the machine chamber 44. Since the machine room cover 87 (see FIG. 7) is usually attached to the machine room 44, the first heat radiation is performed using the air inlet 62 and the air outlet 63 provided in the machine room cover 87. The heat of the compressor 46 and the compressor 24 is released. The machine room base 47 is also provided with an air inlet and outlet (not shown).

  FIG. 8 is a diagram illustrating a control image when the fourth radiator 43 (condensation prevention piping) is switched by the three-way valve 48 in the refrigeration cycle according to the embodiment of the present invention.

  As described above, the refrigerant is flown through the dew condensation prevention pipe, that is, the fourth radiator 43 to heat the partition cover 84, thereby preventing moisture in the air from condensing on the surface of the partition cover 84. .

  Control using the three-way valve 48 to switch between the cycle A side, i.e., the fourth radiator 43 and the cycle B side, i.e., bypassing the fourth radiator 43 and flowing the refrigerant through the pipe 53 Is controlled by the temperature and humidity around the refrigerator obtained by the outside humidity sensor 81 and the outside temperature sensor 82 provided in the refrigerator 1. A temperature sensor and a humidity sensor, that is, detection means are directly attached to the partition cover 84 that covers the surfaces of the partition walls 28, 29, and 40, so that condensation does not occur on the surface of the partition cover 84 according to the detected temperature and humidity. It is conceivable to perform switching control by the valve 48. However, mounting the detection means on the surface of the partition cover 84 or in the partition wall is concerned about the problem of installation space and an increase in the amount of heat penetration due to interference with the door packing contacting the partition cover 84. Therefore, in practice, the switching time between the cycle A side and the cycle B side is controlled according to a predetermined value according to the detected temperature and detected humidity of the outside humidity sensor 81 and the outside temperature sensor 82 provided on the ceiling surface of the refrigerator 1. .

  FIG. 8 shows an example of the three-way valve switching control in the case of a certain ambient temperature detected by the outside humidity sensor 81 and the outside temperature sensor 82. The horizontal axis is the relative humidity, and the vertical axis is the heating rate of the dew condensation prevention pipe. For example, in the case of RH2 where the relative humidity is high, there is a high possibility of condensation on the surface of the partition cover 84. Therefore, the ratio of the time for flowing the refrigerant to the cycle A side (tA2) is long and the time for the refrigerant to flow to the cycle B side The ratio (tB2) is shortened. On the other hand, in the case of RH1 where the humidity is low, the possibility of dew condensation on the surface of the partition cover 84 is reduced, so the ratio of the time for which the refrigerant flows to the cycle A side (tA1) is short and the ratio of the time for the refrigerant to flow to the cycle B side It is preferable to lengthen (tB1). As described with reference to FIG. 5, the surface of the partition cover 84 is heated by the refrigerant to prevent condensation. However, the longer the heating rate of the condensation prevention pipe, that is, the time rate on the cycle A side, the longer the freezing temperature chamber. As a result, heat intrusion into the water increases, and as a result, energy saving tends to deteriorate. In the actual cooling operation, when the compressor 24 is ON, the time on the cycle A side and the cycle B side is determined in advance, and the three-way valve 48 is operated to switch the refrigerant flow path according to the time. In the refrigerator having no flow path switching means such as the three-way valve 48, since it is always on the cycle A side, the heating rate of the dew condensation prevention pipe is 100%.

  FIG. 9 is a time chart showing an example of the cooling operation of the refrigerator according to the embodiment of the present invention. The cooling operation in a stable state after the inside of the chamber reaches a predetermined temperature is based on an operation pattern consisting of a refrigeration operation for cooling the refrigeration temperature zone chamber, a refrigeration operation for cooling the refrigeration temperature zone chamber, and an OFF state in which the compressor stops. These operations are repeated as long as the ambient temperature does not change or food is not charged. That is, the compressor 24 is turned on when the freezer temperature rises to TF1 while the compressor is stopped. When the temperature in the refrigerator compartment decreases and reaches the temperature TR2, the refrigerator operation is terminated, and the refrigerator operation is continued until the temperature in the freezer compartment reaches TF2. Here, the operations of the three-way valve 48 and the two-way valve 49 will be mainly described in relation to the compressor 24. When the compressor 24 is stopped, since the refrigerant in the radiator side, that is, the first radiator 46 to the fourth radiator 43 and the pipe 53 has a higher temperature and pressure than the cooler 7, Due to the difference, the refrigerant on the radiator side flows into the cooler side. As a result, the temperature of the cooler 7 rises and the internal heat load increases, leading to an increase in power consumption. Therefore, when the compressor is stopped, the two-way valve 49 is closed to stop the flow of the refrigerant. Further, in the refrigerator of the present embodiment, the internal fan 9 is turned on, the refrigerator compartment damper 20 is opened, the freezer compartment damper 34 is closed, and cold air is generated by the latent heat of the frost grown on the refrigerator 7 to produce the refrigerator compartment 2. If the two-way valve 49 is closed while the compressor 24 is stopped, the temperature rise of the cooler 7 and the frost can be suppressed, and the cooling efficiency of the refrigerator compartment 2 using the frost as a cold heat source is increased. As a result, it contributes to a reduction in power consumption.

  When the compressor 24 is in operation, the three-way valve 48 is switched between the cycle A side (fourth radiator 43; condensation prevention piping) and the cycle B side (pipe 53) according to the temperature and humidity shown in FIG. (TA, tB) is determined in advance, and the three-way valve 48 is switched accordingly. For example, in the case of RH2 where the humidity and temperature are high, a predetermined time ratio tA2 on the cycle A side and time ratio tB2 on the cycle B side are repeatedly operated. Although the switching time varies depending on the refrigerator, for example, at 30 ° C. outside air and 70% relative humidity, the cycle A side is about 15 minutes and the cycle B side is about 30 minutes.

  In the cooling operation shown in FIG. 9, as an example, the three-way valve 48 is fixed to the cycle A side before the compressor 24 stops. This is because the temperature of the fourth radiator 43 tends to be low when the compressor is stopped, so that the surface temperature of the partition cover 84 is increased by the fourth radiator 43 before the compressor is stopped to prevent condensation. is there. Since the three-way valve 48 is fixed to the cycle A side immediately before the compressor is stopped, it is continuously set to the cycle A side even when the compressor is stopped.

  The three-way valve 48 controls the flow of the refrigerant according to the switching time of the cycle A side (fourth radiator 43; dew condensation prevention piping) and the cycle B side (pipe 53), but after switching to the cycle B side. The refrigerant stays on the cycle A side and on the cycle B side after switching to the cycle A side.

  However, in order to eliminate the shortage of refrigerant after switching the cycle, recovery of the refrigerant remaining in the pipe before switching the cycle every time the cycle is switched results in a decrease in efficiency of the compressor. This leads to an increase in power consumption. Therefore, in order to eliminate the refrigerant shortage without collecting the refrigerant every time the cycle is switched, it is preferable to reduce the pipe volume of the fourth radiator 43 and the pipe 53 and to reduce the pipe volume serving as the liquid phase region. .

  Therefore, in the present embodiment, the pipe volume of the refrigerant flow path pipe b is made smaller than the pipe volume of the refrigerant flow path pipe a. Thereby, the volume of the pipe filled in the liquid phase region is reduced, and it becomes possible to eliminate the shortage of refrigerant while suppressing the power consumption.

  The vegetable room cooling method is not shown because it is not directly related to the operation of the three-way valve 48 and the two-way valve 49.

  FIG. 10a is a diagram schematically showing the state of the refrigerant in the radiator pipe. The first radiator 46 (section ac), the second radiators 41a and 41b, the third radiator 42 (section cd), the fourth radiator 43, and the like connected to the discharge side pipe 66 of the compressor 24. The refrigerant state inside the piping of the radiator constituted by the pipe 53 (section df) will be described. In the refrigerator of this embodiment, the first radiator 46, the second radiators 41a and 41b, and the third radiator 42 are collectively used as the first radiator (refrigerant channel pipe a), and the refrigerant channel The side of the fourth radiator 43 provided with the switching means is the second heat radiating means. A merging pipe 56 (first refrigerant flow path) that merges with the other end of the outlet side pipe 54 of the fourth radiator 43 connected to the A side (three-way valve 48 outlet) of the three-way valve 48, and the three-way valve 48. A joining pipe 56 (second refrigerant passage) that joins the other end of the pipe 53 connected to the B side (outlet of the three-way valve 48) is referred to as a refrigerant passage pipe b.

  The gas refrigerant compressed to a high temperature and high pressure by the compressor 24 releases heat to the outside in the order of the first radiator 46, the second radiators 41 a and 41 b, and the third radiator 42. The state of the refrigerant, the gas-liquid two-phase region during the phase change, the liquid-phase region and the refrigerant change. When the gas phase region (gas phase component) is denoted by reference numeral 67 and the liquid phase region (liquid phase component) is denoted by reference symbol 68, the gas phase region 67 is the section ab and the gas-liquid two phase region (gas phase region 67 and liquid phase region 68). Is the section be, and the liquid phase region 68 is the section ef. When the three-way valve 48 for switching either the fourth radiator 43 or the pipe 53 is provided at the position d in the figure, the section de is a gas-liquid two-phase region where the gas phase component 69 exists.

  FIG. 10b is a diagram schematically showing the state of the refrigerant in the radiator pipe according to the embodiment of the present invention. In the refrigerant flow path switched by the three-way valve 48, that is, in the region of the fourth radiator 43 and the pipe 53, the liquid state is mostly in the liquid phase region 68 (see FIG. 11). Alternatively, the liquid refrigerant tends to remain in the pipe 53 every time the three-way valve 48 is switched. That is, if the pipe volume of the fourth radiator 43 and the pipe 53 branched by the three-way valve 48 shown in FIG. 10a is reduced, the liquid refrigerant remains in the pipe every time switching control is performed by the three-way valve 48. . Therefore, the fourth heat radiator 43 or the gas phase region of the refrigerant in the pipe 53 can be filled with the liquid phase region 68 without leaving the gas phase region of the refrigerant (FIG. 10a).

  Means for reducing the volume of the fourth radiator 43 and the pipe 53 include, for example, reducing the pipe diameter or shortening the pipe length. When the inner diameter of the fourth radiator 43 and the pipe 53 is reduced from φ4.0 mm to φ3.6 mm, the volume can be reduced by about 20%. As shown in FIG. 10b, the second heat radiation means, that is, the fourth heat radiator 43 or the region df of the pipe 53 is filled with the liquid phase region 68, so that the second heat radiation is performed regardless of the operation state of the refrigeration cycle. There is no further increase in the amount of liquid refrigerant remaining in the means. In a refrigerator having means for switching the second heat radiating means, the pipe volume of the second heat radiating means in which the liquid refrigerant accumulates is made smaller than the pipe volume constituting the first heat radiating means, so that the refrigeration cycle can be operated. Regardless, it is possible to make the refrigerant shortage hardly occur even if the second heat radiation means is switched.

  As described above, since the inside of the fourth radiator 43 and the pipe 53 is filled with the liquid phase region, for example, when the three-way valve 48 is switched to the cycle A side shown in FIG. The pipe 53 is in a liquid-sealed state, and the pipe may be damaged by a sudden temperature change. In order to avoid this, the refrigerant leakage amount to the cycle B side is allowed when the three-way valve 48 is fixed to the cycle A side, and when the three-way valve 48 is fixed to the cycle B side, the refrigerant leakage amount to the cycle A side is allowed.

  FIG. 11 is a Mollier diagram showing the operation status of the refrigerator according to the embodiment of the present invention. Thus, the state of the refrigerant on the heat dissipation side described in FIGS. 10a and 10b, that is, the first to fourth radiators will be described on the Mollier diagram. The refrigerant compressed by the compressor 24 is in the order of the first radiator 46, the second radiators 41 a and 41 b, the third radiator 42, and the fourth radiator 43 connected to the pipe 66. Flow (when the three-way valve 48 is fixed to the cycle A side), during which the refrigerant in the pipe dissipates heat to the outside air, so that the gas phase region (section ab), gas-liquid two-phase region (section be), liquid phase region The state changes in the order of (section ef or section df). The refrigerant flowing out of the fourth radiator 43 is decompressed by the throttle 61 and flows into the cooler 7. When the refrigerant passes through the cooler 7, the refrigerant absorbs heat from the internal air and the internal air is cooled, but the cooling capacity can be expressed by an enthalpy difference at the entrance and exit of the cooler 7. Therefore, the cooling capacity when the pressure is reduced from the state f and the refrigerant flows into the cooler 7 can be expressed by Δh1.

  On the other hand, in the case of the configuration of the refrigeration cycle shown in Patent Document 1, another heat radiator is connected to the downstream side of the dew condensation prevention pipe (the fourth heat radiator 43 in the present invention) by being embedded in the side wall surface of the refrigerator. A configuration is disclosed. Usually, heat is radiated to the air outside the cabinet in the order of the dew condensation prevention pipe and the radiator provided downstream of the dew condensation prevention pipe. However, for example, when a heater is placed near the radiator on the downstream side of the dew condensation prevention pipe, the refrigerant is heated by the heater and the refrigerant in the pipe evaporates. May change to state g. In this case, since another radiator is not provided on the downstream side of the radiator, the pressure is reduced from the state g. Therefore, the cooling capacity in the cooler 7 becomes Δh2, and the cooling capacity may be reduced. Since the anti-condensation piping is normally embedded in the opening edge of the storage room, there is no concern that the portion will be heated from the outside, and in the case of a refrigerator equipped with a plurality of radiators, the above phenomenon is avoided. Therefore, it is better to place the dew condensation prevention piping last.

  12a and 12b are diagrams schematically showing the state of the refrigerant inside the three-way valve 48, respectively. A stepping motor and the like for driving the valve bodies 70 and 72 provided inside the three-way valve 48 are omitted. A pipe 51 (C side) is connected to the inlet side opening 71, and a pipe 52 (A side: cycle A side) and a pipe 53 (B side: cycle B side) are connected to the outlet side, respectively. Valve bodies 70 and 72 are provided to control the opening and closing of the pipe 52 and the pipe 53, and when the refrigerant flows through the pipe 52 (A side: cycle A side), the valve body 70 is opened, and the valve body 72 is closed. 53 (B side: cycle B side) When the refrigerant flows, the valve 70 is closed and the valve body 72 is opened. The valve bodies 70 and 72 can be closed when no refrigerant flows through the pipe 52 and the pipe 53, and the valve bodies 70 and 72 can be opened when the refrigerant can flow through the pipe 52 and the pipe 53. The control is performed by a memory circuit installed on the control board 33.

  Since the three-way valve 48 is provided in the middle of the radiator, that is, upstream of the fourth radiator 43 as shown in FIG. 10a, the refrigerant inside the three-way valve 48 is a gas-liquid two-phase as shown in FIG. 12a. In some cases, a flow (gas phase region 67, liquid phase region 68) is formed. When the gas phase region 67 and the liquid phase region 68 are mixed in a complicated manner and pass through the valve bodies 70 and 72 and the inlet side opening 71 of the three-way valve 48, a pipe connected to the three-way valve 48 is provided inside the three-way valve 48. Since there are generally channels having diameters smaller than 51, 52, and 53, refrigerant flow noise may occur due to the reduction or expansion of the refrigerant channel. Therefore, as described with reference to FIG. 10b, the pipe volume of the fourth radiator 43 or the pipe 53 serving as the second heat radiating means is made smaller than the pipe volume of the heat radiating means serving as the first heat radiating means. When the phase area is expanded to the place where the three-way valve 48 is installed, the interior of the three-way valve 48 is filled with the liquid phase area 68 as shown in FIG. 12b, so that the refrigerant passes through the valve bodies 70 and 72 and the inlet side opening 71. It is possible to reduce the refrigerant flow noise during the operation.

  Depending on the operating condition of the refrigeration cycle, the refrigerant passing through the three-way valve 48 may be in a gas-liquid two-phase region. In such a case, the refrigerant flowing from the pipe 51 is temporarily expanded inside the three-way valve 48 larger than the inner diameter of the pipe 51, and the gas phase region 67 and the liquid phase region 68 are moved in the direction of gravity. On the other hand, the refrigerant is allowed to flow out from the valve body 70 (A side: cycle A side) or the valve body 72 (B side: cycle B side) provided on the lower surface of the three-way valve 48 after being divided into two vertically. . The gas phase region 67 and the liquid phase region 68 are divided into two vertically (see FIG. 12a) so that the liquid phase region is formed on the valve bodies 70 and 72 provided on the lower surface of the three-way valve 48 and the inlet side opening 71 side. The posture of the three-way valve 48 when attached to the inside of the machine room 44 can be uniquely determined by attaching the three-way valve 48 to the fixture 50 in advance.

  From the above, the pipe volume of the radiator, which is the second heat radiating means, is compressed after the heat radiating means on the downstream side of the flow path switching means is branched by the flow path switching means and then merged again. The liquid phase area is expanded to the place where the three-way valve 48 is installed by making it smaller than the pipe volume of the radiator which is the first heat radiating means formed between the machine and the refrigerant flow switching means. It is possible to reduce the refrigerant flow noise generated when passing through 48, and also to realize a cooling operation that suppresses the refrigerant flow noise generated when passing through the three-way valve 48 depending on the mounting orientation of the three-way valve 48.

  FIG. 13 is a configuration diagram of a refrigeration cycle of a refrigerator according to another embodiment of the present invention.

  For the refrigeration cycle shown in FIG. 3, a fourth radiator 43 and a pipe serving as a second heat radiation means are provided by a three-way valve 48 having a fully-closed function without providing a two-way valve in front of the throttle 61. The refrigeration cycle is characterized by switching 53. As shown in FIG. 6, the installation place of the two-way valve 49 and the three-way valve 48 is, for example, in the machine room 44. When the width of the refrigerator 1 is small, both the two-way valve 49 and the three-way valve 48 are installed. Since it may be difficult to secure a space, it is also possible to perform control for switching the fourth radiator 43 serving as the second heat radiating means and the pipe 53 using only the three-way valve 48.

  FIG. 14 is a flowchart showing an example of the cooling operation in another embodiment of FIG. That is, with respect to the refrigeration cycle shown in FIG. 13, control is performed to switch the fourth radiator 43 and the pipe 3. Similar to the control shown in FIG. 9, the refrigerator reaches a predetermined temperature, and the operation of the refrigerator in a stable state is basically a refrigeration operation, a refrigeration operation, and an operation including a compressor OFF. These operations are repeated as long as no other input is made. Here, the operation of the three-way valve 48 will be mainly described in relation to the compressor 24.

  When the compressor 24 is stopped, since the refrigerant in the radiator side, that is, the first radiator 46 to the fourth radiator 43 and the pipe 53 becomes higher temperature and pressure than the cooler 7, The refrigerant on the radiator side flows into the cooler side due to the pressure difference. As a result, the heat load on the inside of the cabinet via the cooler 7 increases, leading to an increase in power consumption. Therefore, in order to stop the flow of the refrigerant generated while the compressor is stopped, the refrigerant on the radiator side is collected before the compressor 24 stops. In addition to the cycle A side fixed to the fourth radiator 43 and the cycle B side fixed to the pipe 53 side, both the cycle A side and the cycle B side are closed, or both are opened. It can be. When the refrigerator is operated while being fixed to the cycle A side or the cycle B side for each predetermined time, the refrigerant remains on the cycle A side and the cycle B side which are the high-temperature and high-pressure sides with respect to the cooler 7. . In order to prevent this refrigerant from flowing into the cooler 7 while the compressor is stopped, the three-way valve 48 is fully closed before the compressor 24 is stopped, and the first radiator 46, the second radiators 41a, 41b, the second The refrigerant recovery operation for moving the refrigerant into the third radiator 42 is performed for a time tclose. The refrigerant recovery time is about 3 or 4 minutes, and the three-way valve 48 is kept closed even when the compressor is stopped.

  Even when there is no two-way valve as described above, the refrigerant flow into the cooler 7 when the compressor is stopped can be suppressed by utilizing the fully-closed function of the three-way valve 48. Refrigerant recovery time can be shortened by reducing the pipe volume of the fourth radiator 43 or the pipe 53 constituting the pipe and reducing the pipe volume serving as the liquid phase region, and the operation of the refrigerator with reduced power consumption can be achieved. Is possible.

  As described above, the refrigerator of the present invention has a refrigerant circuit in which a compressor, a heat radiating means, a pressure reducing means, and a cooler are sequentially connected. In the refrigerator, the heat radiating means performs heat radiation to the outside. A first refrigerant flow path comprising a heat radiating means and a second heat radiating means for heating the partition portion, and causing the refrigerant compressed by the compressor to flow to the first heat radiating means and the second heat radiating means. And after passing the refrigerant through the first heat radiating means, a second refrigerant channel that bypasses the first refrigerant channel, the first refrigerant channel, and the second refrigerant channel A switching means for switching, and the internal volume of the first refrigerant flow path and the second refrigerant flow path is made smaller than the internal volume of the first heat dissipation means. That is, the internal volume of the refrigerant passage pipe b (see FIG. 3) is made smaller than the internal volume of the refrigerant passage pipe a (see FIG. 3) to reduce the amount of refrigerant remaining inside the pipe of the second heat radiation means. doing. Therefore, the deterioration of the cooling performance due to the lack of refrigerant can be avoided, and the cooling operation for reducing the power consumption can be performed.

  In addition, the temperature of the refrigerant flowing through the first heat radiating means flows so as not to change within a predetermined range, and then flows so as to have an inflection point at which the temperature starts to gradually decrease. Thereby, a liquid phase area can be expanded to the installation place of a flow-path switching means (three-way valve 48), and the refrigerant | coolant flow noise generated when passing a flow-path switching means can be reduced.

  A first mode for flowing a refrigerant through the first refrigerant flow path; a second mode for flowing a refrigerant through the second refrigerant flow path; and the first refrigerant flow path and the second refrigerant flow path. A third mode in which no refrigerant is allowed to flow, and when at least one of the first mode and the second mode is performed for a predetermined time, the third mode is set in the compressor operating state. carry out. As a result, the operation of collecting the refrigerant remaining in the refrigerant flow pipe b (see FIG. 3) in the compressor is performed, so that the deterioration of the cooling performance due to the lack of refrigerant is avoided and the power consumption is reduced. be able to.

  In addition, a detection unit that detects temperature and humidity is provided, and the time of the first mode and the time of the second mode are changed according to the temperature and humidity detected by the detection unit. Thus, the mode switching time can be controlled according to a predetermined value.

  Further, a refrigerant flow path opening / closing means is provided downstream of the position where the first refrigerant flow path and the second refrigerant flow path merge, and upstream of the pressure reducing means. Thereby, the refrigerant | coolant inflow to the cooler at the time of a compressor stop can be suppressed.

  Further, the flow path switching means is a three-way valve provided outside the storage room of the refrigerator, and the opening / closing outlet portion of the three-way valve is disposed at the lower part. Thereby, the cooling operation which suppressed the refrigerant flow noise generated when passing through the three-way valve can also be realized depending on the mounting orientation of the three-way valve.

DESCRIPTION OF SYMBOLS 1 Refrigerator 9 Blower 20 Refrigeration room dampers 28, 29, 40 Partition wall 34 Freezer compartment dampers 41a, 41b Second radiator 42 Third radiator 43 Fourth radiator (condensation prevention piping)
45 Outside fan (machine room fan)
46 First radiator 48 Three-way valve (flow path switching means)
49 Two-way valve (Refrigerant channel opening / closing means)
51, 52, 53, 54, 57, 59, 60, 64, 66 Pipe 55 Check valve 56 Junction pipe 58 Dryer 61 Restriction 65 Heat exchange section 67, 69 Gas phase region (gas phase component)
68 Liquid phase region (Liquid phase component)
70, 72 Valve body 71 Entrance side opening 80 Door hinge cover 81 Humidity sensor (detection means)
82 Temperature sensor (detection means)
83 Substrate cover 84 Partition cover 85, 86 Heat flow

Claims (6)

In a refrigerator having a refrigerant circuit in which a compressor, a heat radiating means, a pressure reducing means, and a cooler are sequentially connected,
The heat radiating means includes a first heat radiating means for radiating heat to the outside of the cabinet, and a second heat radiating means for heating the partition part,
A first refrigerant flow path for flowing the refrigerant compressed by the compressor to the first heat radiating means and the second heat radiating means;
A second refrigerant flow path that bypasses the first refrigerant flow path after circulating the refrigerant to the first heat radiation means;
Channel switching means for switching between the first refrigerant channel and the second refrigerant channel;
The refrigerator, wherein the internal volume of the first refrigerant flow path and the second refrigerant flow path is smaller than the internal volume of the first heat radiation means.   The temperature of the refrigerant flowing through the first heat radiating means flows so as not to change within a predetermined range, and then flows so as to have an inflection point at which the temperature starts to gradually decrease. Refrigerator. Any of the first mode in which the refrigerant flows through the first refrigerant channel, the second mode in which the refrigerant flows through the second refrigerant channel, the first refrigerant channel, and the second refrigerant channel With a third mode that does not flow refrigerant,
3. The third mode according to claim 1, wherein the third mode is performed in the compressor operating state when at least one of the first mode and the second mode is performed for a predetermined time. refrigerator.   A detection means for detecting temperature and humidity is provided, and the time of the first mode and the time of the second mode are changed according to the temperature and humidity detected by the detection means. 3. The refrigerator according to 3.   The refrigerant flow path opening / closing means is provided downstream of the position where the first refrigerant flow path and the second refrigerant flow path merge, and upstream of the pressure reducing means. 2. The refrigerator according to 2.   The flow path switching means is a three-way valve provided outside the storage room of the refrigerator, and is arranged so that an opening / closing outlet portion of the three-way valve is located at a lower part. Refrigerator.