JP2013145079A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator capable of reducing power consumption during defrosting and that during a pull-down period while ensuring defrosting reliability.SOLUTION: The refrigerator includes: a storage room including at least a cold room 1; a cooling room 7 having a cooler 25; an air duct connecting the cooling room 7 and the storage room to each other; a tray 29 disposed below the cooler; a heating means heating the cooler 25 and the tray 29; a first thermistor 61 arranged in the cooler 25; a second thermistor 62 arranged in the tray 29; and a control means 70 determining an end of defrosting operation based on detection results of the first thermistor 61 and the second thermistor 62. The first thermistor 61 is disposed in the position on the upstream side of air flow in the cooler 25 and corresponding to a return port 46 for introducing air from the cold room 1 to the cooling room 7. The second thermistor 62 is disposed approximately just below the first thermistor 61.

Description

  The present invention relates to a refrigerator, and more particularly to melting of frost attached to a cooler or the like.

  In the refrigerator, a cooling operation is performed in order to cool a cooling object such as food in a storage room (for example, a refrigerator room, a freezer room, a vegetable room, etc.). At this time, air in the storage room is circulated by the internal fan, the air is cooled by a cooler, and sent out to the storage room, thereby cooling food stored in the storage room. Here, when the outside air flows into the storage chamber by opening and closing the door of the refrigerator, or the moisture of the food in the storage chamber evaporates into the storage chamber, the absolute humidity of the air in the storage chamber increases. When the absolute humidity rises, moisture in the storage room air sublimates on the surface of the cooler, and frost adheres to the cooler. For this reason, for example, when the cooling operation is performed for about one day, the cooler may be covered with frost.

  When frost adheres to the cooler, the airflow resistance of the cooler increases, so the air volume of the air sent into the storage chamber decreases. Moreover, the thermal resistance between the refrigerant flowing in the cooler and the air in the storage room increases, and the refrigeration capacity decreases. Therefore, in the refrigerator, for example, defrosting is performed every predetermined time (for example, once a day) to suppress an increase in ventilation resistance and an increase in thermal resistance of the cooler.

  In order to defrost the refrigerator's cooler, for example, a refrigerator with a function of melting the frost of the cooler by adding a heater near the cooler and convection of the heater's radiant heat and the ambient air warmed by the heater is proposed Has been. However, in such a refrigerator, since the rate at which the heat of the heater leaks into the storage chamber increases, the temperature in the storage chamber rises during defrosting, which may reduce food quality. In addition, there is a problem that the amount of power consumption increases as the heater is energized.

  Moreover, the refrigerator which has a function which defrosts a cooler comprised the refrigerant circuit (hot gas defrost circuit) which can supply the refrigerant | coolant compressed to high temperature and high pressure with the compressor to a cooler, and can melt | dissolve frost. There is a refrigerator. However, hot gas defrosting (hereinafter referred to as defrosting operation) that melts frost from the inside of such a cooler (hereinafter referred to as defrosting operation) easily slides onto the tray without being completely melted. For this reason, the frost that could not be melted may block the drain hole of the tray.

  Then, the refrigerator which made the tray (henceforth a bypass piping) contact the tray through which the high-temperature refrigerant | coolant flows among piping which comprises a hot gas defrost circuit is proposed (for example, refer patent document 1). The technique described in Patent Document 1 transmits heat of the refrigerant flowing through the bypass pipe to the tray through the bypass pipe, and heats the frost that has slipped onto the tray to melt the frost. In addition, a refrigerator in which a heater is disposed as a tray heating means in a hot gas defrosting circuit has been proposed (see, for example, Patent Document 2).

JP 2007-218537 A (FIG. 1) Japanese Patent Laying-Open No. 2005-249254 (FIG. 1)

  In the refrigerator described in Patent Document 1, the defrost release sensor is attached to the pipe immediately downstream of the cooler, and when the temperature in the pipe immediately downstream becomes higher than 3 ° C., the frost attached to the cooler is completely melted. As a result, the hot gas defrosting has been completed. However, after the frost slips from the cooler during hot gas defrosting, the temperature of the cooler rises in a short time. For this reason, although the frost which slipped from the cooler to the tray is not melted, the defrosting operation may be terminated, and the slipped frost may remain on the tray.

  In order to prevent such a defrosting operation from occurring quickly, if the operation time is made longer than necessary, the power consumption during defrosting is increased. In addition, the temperature of the air in the storage room is greatly increased, which may damage food in the storage room. Furthermore, there is a possibility that the time for the operation for cooling the storage chamber to the set temperature after defrosting (hereinafter referred to as pull-down operation) is lengthened and the power consumption during pull-down is increased.

  For this reason, for example, in the refrigerator described in Patent Document 2, the first temperature detection means (hereinafter referred to as a first thermistor) is used as a cooler, and the second temperature detection means (hereinafter referred to as a second thermistor). ) Is provided on the tray, and the defrosting operation is finished assuming that the frost on the cooler and the tray is completely melted when the first thermistor and the second thermistor are equal to or higher than the set temperature.

  However, since the installation position of the first thermistor is not specified in Patent Document 2, the refrigerator described in Patent Document 2 has the following problems. In other words, when changing the design of a heat insulation box formed with a storage room or a cooling room for storing a cooler, or when installing a cooler with the same configuration in a heat insulation box of a different refrigerator, each storage room was passed through. The positional relationship between the return port for the air to flow into the cooling chamber and the cooler may be different. The flow of return air in the cooling chamber differs depending on the positional relationship between the return port and the cooler. For this reason, depending on the positional relationship between the return port and the cooler, frost is formed in places other than the place where the first thermistor is disposed. Therefore, the presence or absence of frost in the defrosting operation cannot be accurately determined, and melting or the like occurs. There was a problem that the defrosting operation was terminated with the frost that could not be removed remaining in the cooler.

  Further, in Patent Document 2, since the installation position of the second thermistor is not specified, when frost slides at a place other than the place where the second thermistor is disposed, the frost that has fallen from the cooler is removed in a state where it remains on the tray. There was a problem that the frost operation was terminated.

  That is, reducing the power consumption during defrosting in the defrosting operation and ensuring the defrosting reliability are in a trade-off relationship, and even using the techniques disclosed in Patent Literature 1 and Patent Literature 2. The effect obtained is not maximized.

  The present invention has been made in order to solve the above-described problems, and a refrigerator capable of reducing power consumption during defrosting and power consumption during pull-down while ensuring defrosting reliability. The purpose is to obtain.

  The refrigerator according to the present invention has a storage chamber for storing an object to be cooled, a cooling chamber provided with a cooler for cooling the air supplied to the storage chamber, and a blowout port and a return port opened to the cooling chamber, An air path connecting the cooling chamber and the storage chamber, and the air cooled by the cooler from the blowout port is caused to flow out to the storage chamber, and the air that has flowed out of the storage chamber is discharged from the return port to the cooling chamber. An in-compartment fan that flows into the cooler, a tray that is disposed below the cooler and receives frost and water sliding down from the cooler, a first heating means that heats the cooler, and a first that heats the tray Two heating means; a first temperature detection means provided in the cooler for detecting the temperature of the cooler; a second temperature detection means provided in the tray for detecting the temperature of the tray; The first and second temperature detecting means Control means for judging the end of the defrosting operation by heating of the first and second heating means based on the detection result, and having at least a refrigeration room as the storage room, and the refrigeration as the return port At least a first return port through which the air flowing out of the chamber flows into the cooling chamber, and the first temperature detection means corresponds to the upstream side of the air flow in the cooler and the first return port. The second temperature detection means is arranged at a position almost directly below the first temperature detection means.

  In the present invention, since the arrangement positions of the first temperature detection means and the second temperature detection means are specified as described above, power consumption and pull-down during defrosting are ensured while ensuring defrost reliability. Power consumption at the time can be reduced.

It is side surface sectional drawing of the refrigerator which concerns on embodiment of this invention. It is a refrigerant circuit figure of the refrigerator which concerns on embodiment of this invention. It is explanatory drawing (front sectional drawing) which shows the air path structure of the refrigerator which concerns on embodiment of this invention. It is explanatory drawing which shows the cooling chamber 7 of the refrigerator which concerns on embodiment of this invention. It is a top view of the liquid receiving part 8 of the refrigerator which concerns on embodiment of this invention. It is side surface sectional drawing which shows an example of the cooling chamber of the refrigerator which concerns on embodiment of this invention. It is side surface sectional drawing which shows another example of the cooling chamber of the refrigerator which concerns on embodiment of this invention. It is side surface sectional drawing which shows another example of the cooling chamber of the refrigerator which concerns on embodiment of this invention. It is side surface sectional drawing which shows another example of the cooling chamber of the refrigerator which concerns on embodiment of this invention. It is a block diagram which shows the apparatus structure of the control system of the refrigerator which concerns on embodiment of this invention. It is a figure which shows the temperature change of the cooler 25 and the tray 29 at the time of the defrost operation of the refrigerator which concerns on embodiment of this invention. It is a flowchart of the defrost operation control of the refrigerator which concerns on embodiment of this invention.

Embodiment.
FIG. 1 is a side sectional view of a refrigerator according to an embodiment of the present invention. FIG. 1 shows the refrigerator according to the present embodiment with the front side (front side) of the refrigerator being the left side of the page. Moreover, in this Embodiment, as shown in FIG. 1, as a refrigerator, as shown in FIG. 1, the refrigerator compartment 1, the freezer compartment 4, the vegetable compartment 5, and ice which store a cooling target object (foodstuff etc.) in the outline which is a heat insulation box. An example will be described in which an ice making chamber 2 to be stored, and a switching chamber 3 that can be switched to a temperature zone of the freezing chamber 4 or the refrigeration chamber 1 are respectively provided. Here, in the following description, unless otherwise specified, the refrigerator compartment 1, the ice making compartment 2, the switching compartment 3, the freezer compartment 4, and the vegetable compartment 5 are collectively referred to as a storage compartment.

  As shown in FIG. 1, the refrigerator of the present embodiment has a cooling chamber 7 formed on the back side. The cooling chamber 7 has a cooler 25, an internal fan 6, and a liquid receiving unit 8. In the normal operation of the refrigerator, the cooler 25 cools the air supplied to the storage chamber by exchanging heat with the refrigerant passing through the inside. The internal fan 6 is a blower that forms an air flow (a flow for circulating the air in the storage chamber) that allows air from the storage chamber to pass through the cooler 25 and sends the cooled air to the storage chamber again. This internal fan 6 is disposed above the cooler 25. The liquid receiver 8 has equipment for receiving frost melting water (drain water) dripping from the cooler 25, frost sliding down, etc. during the defrosting operation.

  FIG. 2 is a refrigerant circuit diagram of the refrigerator according to the embodiment of the present invention. As shown in FIG. 2, the refrigerator according to the present embodiment connects, for example, a compressor 21, a flow path switching valve 22, a condenser 23, a capillary tube 24, a cooler 25, a header 26, a bypass pipe 27, and a tray pipe 28. Thus, a refrigerant circuit is configured.

  The compressor 21 compresses the gas-phase refrigerant sucked from the suction side to high pressure and high temperature, and sends it out from the discharge side. The compressor 21 has a discharge side connected to the flow path switching valve 22 via a refrigerant pipe, and a suction side connected to the header 26 via the refrigerant pipe.

  The flow path switching valve 22 serving as switching means switches the flow of the refrigerant sent out from the compressor 21. The flow path switching valve 22 has a refrigerant inlet A1, an outlet A2, and an outlet A3, and connects the inlet A1 and the outlet A2 or connects the inlet A1 and the outlet A3. Can be selected by switching. Here, inflow port A1 is connected with the discharge side of compressor 21 via refrigerant piping. The outlet A2 is connected to the condenser 23 via a refrigerant pipe. The outlet A3 is connected to the bypass pipe 27. And when the connection which forms a flow path between inflow port A1 and outflow port A2 is made, the air of a refrigerator is cooled by cooling the cooler 25. FIG. Hereinafter, the connection that forms the flow path between the inlet A1 and the outlet A2 is referred to as “normal connection”, and the operation of cooling by the cooler 25 by the normal connection is referred to as “normal operation”. Moreover, when the connection which forms a flow path between inflow port A1 and outflow port A3 is carried out, the cooler 25 is heated with the refrigerant | coolant from the compressor 21 of the cooler 25. FIG. Hereinafter, the connection that forms the flow path between the inflow port A1 and the outflow port A3 is referred to as “defrost connection”, and the operation in the defrost connection state is referred to as “defrost operation”.

  The condenser 23 condenses the high-temperature and high-pressure gas-phase refrigerant from the compressor 21 by, for example, heat exchange with air outside the refrigerator when the flow path switching valve 22 is normally connected. The condenser 23 has a refrigerant inlet side connected to the flow path switching valve 22 via a refrigerant pipe, and a refrigerant outlet side connected to the capillary tube 24 via the refrigerant pipe.

  The capillary tube 24 serving as a decompression means (a throttling device) decompresses the liquid-phase or gas-liquid two-phase refrigerant flowing from the condenser 23 into a low-temperature and low-pressure gas-liquid two-phase state. The capillary 24 has a refrigerant inlet side connected to the condenser 23 via a refrigerant pipe, and a refrigerant outlet side connected to the cooler 25 via a tray pipe 28. The refrigerant outlet side of the capillary tube 24 is also connected to the bypass pipe 27.

  For example, the tray pipe 28 is disposed on the lower surface of a tray 29 described later, and is fixed in contact with the tray 29 with a metal tape (not shown) having high thermal conductivity. Thereby, the tray 29 can be effectively heated during the defrosting operation, and the frost sliding down on the tray 29 can be melted. In the present embodiment, for example, a part of the pipe connecting the capillary tube 24 and the cooler 25 is configured. The refrigerant inlet side is connected to the capillary tube 24 and the bypass pipe 27, and the refrigerant outlet side is connected to the cooler 25. When the flow path switching valve 22 is normally connected and performing normal operation, the gas-liquid two-phase refrigerant that has passed through the capillary 24 passes. At this time, it functions as a subcooler and evaporates part of the liquid phase refrigerant. Further, when the flow path switching valve 22 is defrosted and performing a defrosting operation, it functions as a sub radiator, and a high-temperature and high-pressure gas phase that has passed through the flow path switching valve 22 and the bypass pipe 27 from the compressor 21. A refrigerant (which may be a gas-liquid two-phase refrigerant) is radiated. As a result, the frost sliding down on the tray 29 is melted.

  For example, even if a part of the bypass pipe 27 is configured as the tray pipe 28 and the refrigerant outlet of the bypass pipe 27 is connected to the cooler 25, the tray 29 is heated in the defrosting operation to melt the frost. Can be made. Further, a part of the pipe connecting the cooler 25 and the compressor 21 is configured as a tray pipe 28 so that the refrigerant inlet side is connected to the cooler 25 and the refrigerant outlet side is connected to the compressor 21. In the defrosting operation, the tray 29 can be heated to melt the frost. Further, the tray 29 may be heated by heating means such as a pipe heater without arranging the tray pipe 28. At this time, the refrigerant outlet side of the bypass pipe 27 is connected to the cooler 25.

  As described above, when the flow path switching valve 22 is normally connected and performing the normal operation, the cooler 25 is supplied with the low-temperature and low-pressure refrigerant in the gas-liquid two-phase state fed through the tray pipe 28 and the cooling chamber 7. The inside air (air supplied to the storage chamber) is subjected to heat exchange, and the gas-liquid two-phase low-temperature and low-pressure refrigerant is evaporated and vaporized. The cooler 25 functions as a radiator when the flow path switching valve 22 is defrosted and performing a defrosting operation, and is a high-temperature and high-pressure gas-phase refrigerant (gas-liquid two-phase refrigerant) that has passed through the tray pipe 28. Heat radiation). Thereby, the cooler 25 is heated from the inside, and the frost adhering to the cooler 25 is melted.

  The header 26 is for separating the liquid-phase refrigerant from the refrigerant flowing from the cooler 25 through the refrigerant pipe, and causing the compressor 21 to suck the gas-phase refrigerant. The header 26 has a refrigerant inlet side connected to the cooler 25 via a refrigerant pipe, and a refrigerant outlet side connected to the suction side of the compressor 21 via the refrigerant pipe.

  The bypass pipe 27 is configured such that when the flow path switching valve 22 is defrosted, the high-temperature and high-pressure gas-phase refrigerant (which may be a gas-liquid two-phase refrigerant) discharged from the compressor 21 is supplied to the condenser 23 and the capillary tube 24. Is bypassed and passed through the tray pipe 28 and the cooler 25. The bypass pipe 27 has a refrigerant inlet side connected to the flow path switching valve 22 and a refrigerant outlet side connected to the tray pipe 28.

  FIG. 3 is an explanatory view (front sectional view) showing the air passage structure of the refrigerator according to the embodiment of the present invention. Here, a refrigerator in which the refrigerator compartment 1, the ice making compartment 2, the switching compartment 3, and the freezer compartment 4 are connected by an air passage from the cooling compartment 7 and the vegetable compartment 5 is connected to the refrigerator compartment 1 by an air passage is taken as an example. Use.

  The air cooled by the cooler 25 is sent into the refrigerator compartment 1 from the outlet 41 of the refrigerator compartment 1 via the air passage A connecting the cooling compartment 7 and the refrigerator compartment 1 by the internal fan 6. Since the air in the refrigerator compartment 1 exchanges heat with food in the refrigerator compartment 1, air that flows in from the outside of the refrigerator when the door of the refrigerator compartment 1 is opened and closed, the temperature rises. In addition, the amount of moisture in the refrigerator compartment 1 increases due to the inflow of air having a high absolute humidity.

  Next, the air in the refrigerator compartment 1 flows into the air path B connecting the refrigerator compartment 1 and the vegetable compartment 5 from the return port 46 of the refrigerator compartment 1. Some percent of the air flowing into the air passage B returns directly to the cooling chamber 7 from the return port 46 without passing through the vegetable chamber 5. The rest flows into the vegetable compartment 5 from the outlet 44 of the vegetable compartment 5. The air that has flowed into the vegetable compartment 5 rises in temperature and amount of water, as does the air in the refrigerator compartment 1. Then, the return port 46 returns to the cooling chamber 7.

Then, the cold air that has become hotter and humider than when it is sent out from the cooling chamber 7 is heat-exchanged in the cooler 25, becomes cold air of low temperature and low humidity again, and is then sent out to the refrigerating chamber 1. For this reason, frost due to dehumidified moisture is preferentially attached to the vicinity of the cooler 25 that is located upstream of the flow of air passing through the cooler 25 and closer to the return port 46.
Here, the return port 46 through which the air passing through the refrigerator compartment 1 returns to the cooling chamber 7 corresponds to the first return port of the present invention.

The air cooled by the cooler 25 is sent into the freezer compartment 4 from the outlet 43 of the freezer compartment 4 by the internal fan 6. Since the air in the freezer compartment 4 exchanges heat with food in the freezer compartment 4, air that flows in from the outside of the refrigerator by opening and closing the door of the freezer compartment 4, the temperature rises. In addition, the amount of water in the freezer compartment 4 increases due to the flow of air with high absolute humidity. However, since the internal volume of the freezer compartment 4 is smaller than the internal volume of the refrigerator compartment 1, the amount of water contained in the air in the freezer compartment 4 is less than that of the refrigerator compartment 1. Next, the air in the freezer compartment 4 returns from the return port 45 to the cooling chamber 7.
Here, the return port 45 corresponds to the second return port of the present invention.

  FIG. 4 is an explanatory diagram showing the cooling chamber 7 of the refrigerator according to the embodiment of the present invention. FIG. 5 is a plan view of liquid receiver 8 of the refrigerator according to the embodiment of the present invention. 4A is a view of the cooling chamber 7 viewed from the back side of the refrigerator, and FIG. 4B is a cross-sectional view taken along line AA of FIG. 4A.

  As shown in FIGS. 4 and 5, the liquid receiving unit 8 includes a tray 29 and the tray pipe 28 described above. As shown in FIG. 4, in the present embodiment, the tray pipe 28 is disposed on the lower surface of the tray 29. However, the tray pipe 28 may be disposed on the upper surface side of the tray 29, for example, as long as it can transfer heat to the tray 29 during the defrosting operation.

  The tray 29 receives molten water and frost that slide down from the cooler 25. Here, by configuring the tray 29 with a metal material having a high thermal conductivity, the frost that has slipped down can be melted effectively by heating it during the defrosting operation. When the tray pipe 28 is provided on the upper surface side of the tray 29, the material of the tray 29 may be made of a material having a low thermal conductivity and good heat insulation, such as a polymer material. Furthermore, the material of the tray 29 may be made of, for example, a metal material having a high conductivity, and a heat insulating material having a lower heat conductivity than the tray 29 and a good heat insulating property may be provided on the lower surface of the tray 29. Thereby, it becomes difficult for the heat | fever of a refrigerant | coolant to conduct to parts other than frost, for example, the cooling chamber 7, etc. at the time of defrost operation, and useless heat dissipation can be suppressed.

  A drain hole 30 is provided in the center of the tray 29. Melted water of frost that has slipped down to the liquid receiver 8 or melted water of frost that has melted in the liquid receiver 8 flows through the drain pipe 9 that leads to the drain hole 30 and is drained to the evaporating dish 10. Here, since the drain hole 30 has a mesh structure, it is possible to prevent unmelted frost from flowing into the drain pipe 9 and freezing in the middle of the drain pipe 9.

  The water (drain water) stored in the evaporating dish 10 is vaporized by, for example, heat generated by operating the compressor 21, air sent by a fan arranged in the machine room, and the like, and is discharged outside the refrigerator. The

  Here, the frost that has slipped into the drain hole 30 has a small contact area with the tray 29, and therefore, the amount of heat transferred from the tray pipe 28 by heat conduction is insufficient, and is difficult to melt. Therefore, as shown in FIG. 5, a part (I) of the tray pipe 28 is arranged in the vicinity of the drain hole 30, and the amount of heat supplied to the vicinity of the drain hole 30 is increased, so that the drain hole 30 is caused by the frost that has fallen. Blocking can be prevented. For example, when the tray pipe 28 is provided on the upper surface of the tray 29, a part (I) of the tray pipe 28 may pass through the drain hole 30.

As shown in FIG. 4, the cooler 25 is provided with a first thermistor 61 that detects the temperature of the cooler 25. Based on the temperature of the cooler 25 detected by the first thermistor 61, the control means 70 described later determines the end of the defrosting operation. The first thermistor 61 is desirably arranged in the cooler 25 on the upstream side of the air flowing from the storage chamber into the cooling chamber 7 and in the vicinity of the return port of the air passage. The first thermistor 61 is desirably arranged in the vicinity of the return port through which air that has flowed out of the storage chamber having the highest humidity passes. That is, the first thermistor 61 desirably detects the temperature at a position where the amount of frost formation is large on the surface of the cooler 25. If the first thermistor 61 determines that the frost at this position has melted completely by detecting the temperature at the position where the frost formation is considered to be the slowest, the frost is melted completely. It can be determined that the attached frost is completely melted, and even if only one first thermistor 61 is attached, the reliability of defrosting is improved.
Here, the first thermistor 61 corresponds to the first temperature detection means in the present invention. The detailed arrangement position of the first thermistor 61 will be described with reference to FIGS.

Further, as shown in FIGS. 4 and 5, the tray 29 is provided with a second thermistor 62 that detects the temperature of the tray 29. Based on the temperature of the tray 29 detected by the second thermistor 62, the control means 70 described later determines the end of the defrosting operation. Here, the second thermistor 62 is attached at a position almost directly below the first thermistor 61 where the amount of frost sliding down the cooler 25 is large. When the second thermistor 62 detects the temperature at the position where the frost is most likely to fall on the tray 29, it is determined that the frost at this position has completely melted. It will be determined that it has melted, leading to improved reliability of defrosting.
Here, the second thermistor 62 corresponds to the second temperature detection means in the present invention. Note that the arrangement position of the second thermistor 62 does not have to be strictly below the first thermistor 61, and can be any position in the tray 29 that can detect the temperature in the vicinity of the position immediately below the first thermistor 61. Good.

  Next, the detailed arrangement position of the first thermistor 61 will be described. As described above, the air that has returned to the cooling chamber 7 from the return port 46 is the air that has passed through the refrigerating chamber 1. For this reason, in the cooler 25, frost adheres preferentially to the position where the air returned from the return port 46 to the cooling chamber 7 flows. For this reason, in the present embodiment, the first thermistor 61 is disposed at a position corresponding to the return port 46 on the upstream side of the air in the cooler 25. For example, the first thermistor 61 is arranged as shown in FIGS. 6 to 8 corresponding to the position of the return port 46, for example.

(Details of arrangement position of first thermistor 61)
FIG. 6 is a side sectional view showing an example of the cooling chamber of the refrigerator according to the embodiment of the present invention. In FIG. 6, the left side of the paper is the front side (front side) of the refrigerator.
The return port 46 of the refrigerator compartment 1 and the return port 45 of the freezer compartment 4 are disposed below the cooler 25 on the front side surface of the cooling chamber 7. The return port 46 of the refrigerator compartment 1 is disposed below the return port 45 of the freezer compartment 4. In such a configuration, the return air from the freezer compartment 4 travels the shortest distance from the return port 45 to the internal fan 6. For this reason, the return air from the freezer compartment 4 flows in the cooler 25 on the front side (return port side) from the center in the front-rear direction of the refrigerator. On the other hand, the return air from the freezer compartment 1 flows from the freezer compartment 4 over the shortest distance from the return port 46 to the internal fan 6, so that the return air from the freezer compartment 4 is avoided. The cooler 25 flows from the center in the front-rear direction of the refrigerator to the rear (opposite the return port). For this reason, when the cooling chamber 7 is configured as shown in FIG. 6, the first thermistor 61 is arranged behind the center in the front-rear direction of the refrigerator in the cooler 25 (on the opposite side to the return port). It is possible to detect the temperature at a location where the amount of frost formation at 25 is large.

FIG. 7 is a side sectional view showing another example of the cooling chamber of the refrigerator according to the embodiment of the present invention. In FIG. 7, the left side of the drawing is the front side (front side) of the refrigerator.
The return port 46 of the refrigerator compartment 1 and the return port 45 of the freezer compartment 4 are disposed below the cooler 25 on the front side surface of the cooling chamber 7. The return port 46 of the refrigerator compartment 1 is disposed above the return port 45 of the freezer compartment 4. In such a configuration, the return air from the refrigerator compartment 1 moves the shortest distance from the return port 46 to the internal fan 6. For this reason, the return air from the refrigerator compartment 1 flows the front side (return port side) of the cooler 25 from the center in the front-rear direction of the refrigerator. On the other hand, since the return air from the freezer compartment 4 flows back from the refrigerator compartment 1 over the shortest distance from the return port 45 to the internal fan 6, so as to avoid the return air from the refrigerator compartment 1, The cooler 25 flows from the center in the front-rear direction of the refrigerator to the rear (opposite the return port). Therefore, when the cooling chamber 7 is configured as shown in FIG. 7, the first thermistor 61 is arranged on the front side (return port side) of the cooler 25 from the center in the front-rear direction of the refrigerator. It is possible to detect the temperature at a location where the amount of frost formation is large.

FIG. 8 is a side sectional view showing still another example of the cooling chamber of the refrigerator according to the embodiment of the present invention. In FIG. 8, the left side of the paper is the front side (front side) of the refrigerator.
For example, when the vertical position of the return port 46 of the refrigerator compartment 1 and the return port 45 of the freezer compartment 4 are the same, the other return ports ( There is a case in which the return path 46 of the refrigerator compartment 1 is arranged independently without the air path) being arranged. Moreover, the return port 46 of the refrigerator compartment 1 may be arrange | positioned facing the direction of the cooler 25. FIG. In such a configuration, the return air from the refrigerator compartment 1 moves the shortest distance from the return port 46 to the internal fan 6. For this reason, the return air from the refrigerator compartment 1 flows the front side (return port side) of the cooler 25 from the center in the front-rear direction of the refrigerator. Therefore, when the cooling chamber 7 is configured as shown in FIG. 8, the first thermistor 61 is arranged on the front side (return port side) of the cooler 25 from the center in the front-rear direction of the refrigerator. It is possible to detect the temperature at a location where the frost formation amount is large.

FIG. 9 is a side sectional view showing still another example of the cooling chamber of the refrigerator according to the embodiment of the present invention. In FIG. 9, the left side of the paper is the front side (front side) of the refrigerator.
For example, when the vertical position of the return port 46 of the refrigerator compartment 1 and the return port 45 of the freezer compartment 4 are the same, the other return ports ( There is a case in which the return path 46 of the refrigerator compartment 1 is arranged independently without the air path) being arranged. In addition, the return port 46 of the refrigerator compartment 1 may be arranged facing the tray 29. In such a configuration, the return air from the refrigerator compartment 1 moves from the return port 46 to the internal fan 6 via the tray 29. For this reason, the return air from the refrigerator compartment 1 flows in the cooler 25 from the center in the front-rear direction of the refrigerator (on the opposite side to the return port). Therefore, when the cooling chamber 7 is configured as shown in FIG. 9, the first thermistor 61 is arranged on the rear side (opposite side of the return port) of the cooler 25 from the center in the front-rear direction of the refrigerator. It is possible to detect the temperature at a location where the amount of frost formation at 25 is large.

  6 and 7, the location of the first thermistor 61 is not affected by the direction of the air path. That is, for example, in FIG. 6, even when the return port 46 of the refrigerator compartment is facing downward or when the return port 45 of the freezer compartment is facing upward, the refrigerator is refrigerated so as to avoid return air from the freezer compartment 4. Since the chamber return air flows, the first thermistor 61 can be similarly arranged.

(Defrosting operation)
Next, a defrosting operation operation of the refrigerator configured as in the present embodiment will be described.

  FIG. 10 is a block diagram showing a device configuration of a control system of the refrigerator according to the embodiment of the present invention. The control means 70 shown in FIG. 10 controls equipment in the refrigerator. In particular, in the present embodiment, it is determined whether or not to end the defrosting operation based on the temperatures detected by the first thermistor 61 and the second thermistor 62. In addition, at the start and end of the defrosting operation, control related to the setting relating to the motor speed of the compressor 21 in the refrigerant circuit, rotation and stop of the internal fan 6, and connection switching of the flow path switching valve 22 are performed.

  FIG. 11 is a diagram showing temperature changes of the cooler 25 and the tray 29 during the defrosting operation of the refrigerator according to the embodiment of the present invention. The vertical axis in FIG. 11 shows the temperature of the cooler 25 detected by the first thermistor 61 and the temperature of the tray 29 detected by the second thermistor 62, and the horizontal axis shows the elapsed time from the start of defrosting. Show.

  The refrigerator according to the present embodiment performs a normal operation for cooling food in the storage room continuously for a predetermined time. During normal operation, air exchanged with the refrigerant is sent into the storage chamber. At this time, moisture contained in the air adheres to the surface of the cooler 25 or the like as frost, which deteriorates the efficiency of heat exchange. Therefore, the control means 70 performs a normal operation for a predetermined time (for example, about one day), and then performs the defrost operation by switching the flow path switching valve 22 to the defrost connection to remove the attached frost.

  As shown in FIG. 11, when the defrosting operation is started, the temperature of the tray 29 (including the frost on the tray 29) receives heat from the high-temperature refrigerant in the tray pipe 28 and rises to 0 ° C. (B1). On the other hand, the cooler 25 (including frost on the surface of the cooler 25) also receives heat from the high-temperature refrigerant flowing in the cooler 25 and rises to 0 ° C. (A1). Here, since the heat capacity of the cooler 25 is generally larger than the heat capacity of the tray 29, the cooler 25 becomes 0 ° C. later than the tray 29.

  When the temperature of the tray 29 reaches 0 ° C., the heat of the refrigerant is used to melt the frost of the tray 29 (phase change from solid to liquid). For this reason, the temperature of the tray 29 becomes 0 ° C. until the frost on the tray 29 is completely melted (B2). When the frost on the tray 29 is completely melted, the temperature of the tray 29 rises (B3).

  Between B1 and B3, the frost attached to the cooler 25 is also melted (A2). Then, when the frost melting of the cooler 25 proceeds to some extent, the frost slides from the cooler 25 to the tray 29. For this reason, the temperature of the tray 29 that has risen without frost rapidly decreases (B4, A2). Then, the heat of the refrigerant flowing in the tray pipe 28 is used again for melting of the frost in the tray 29 (phase change from solid to liquid) until the frost in the tray 29 is completely melted. The temperature of 29 becomes constant at 0 ° C. (B5).

  Since the frost does not exist in the cooler 25 between B4 and B5, the temperature of the cooler 25 rises (A3). On the other hand, when the frost sliding down on the tray 29 is completely melted, the temperature of the tray 29 rises again (B6). Therefore, when the temperature of the cooler 25 is equal to or higher than the first set temperature and the temperature of the tray 29 is equal to or higher than the second set temperature, the defrosting operation is terminated (B6, A3).

  FIG. 12 is a flowchart of the defrosting operation control of the refrigerator according to the embodiment of the present invention. Based on FIG. 12, the control at the time of the defrost operation which the control means 70 performs is demonstrated. Note that STEPa and STEPb in FIG. 12 correspond to STEPa and STEPb in FIG.

  When the normal operation is performed for a predetermined time (for example, about one day), the control means 70 starts the defrosting operation (S101).

  When the defrosting operation is started, the control means 70 stops the operation of the internal fan 6 (S102). And the control means 70 switches the flow-path switching valve 22 to a defrost connection (S103). As a result, the high-temperature and high-pressure refrigerant discharged from the compressor 21 is supplied to the tray pipe 28 and the cooler 25 via the bypass pipe 27. Here, the control means 70 fixes the (motor) rotation speed of the compressor 21 (S104). At this time, by setting the rotation speed to a high speed so that the discharge pressure of the compressor 21 does not exceed the specified pressure, more heat can be supplied, the defrosting time can be shortened, and the defrosting operation can be performed. Power consumption can be reduced.

  Thereafter, the control means 70 detects the temperature related to the detection of the first thermistor 61 as the temperature of the cooler 25 (S105). Further, the control means 70 detects the temperature related to the detection of the second thermistor 62 as the temperature of the tray 29 (S106). Then, the control means 70 records the detected temperature of the cooler 25 and the temperature of the tray 29.

  Next, the control means 70 determines whether or not the temperature of the cooler 25 is higher than the first set temperature (S107, STEPa). When it is determined that the temperature of the cooler 25 is equal to or lower than the first set temperature (S107; NO), the control unit 70 returns to S105 and performs determination based on the temperature of the cooler 25 again.

  On the other hand, when it is determined that the temperature of the cooler 25 is higher than the first set temperature (S107; YES), the control means 70 determines whether the temperature of the tray 29 is higher than the second set temperature (S108, STEPb).

  When it is determined that the temperature of the tray 29 is equal to or lower than the second set temperature (S108; NO), the control unit 70 returns to S105 and performs determination based on the temperature of the cooler 25 again. Moreover, if it determines with the temperature of the tray 29 being higher than 2nd setting temperature (S108; YES), the control means 70 will switch the flow-path switching valve 22 to normal connection as what defrosting was complete | finished (S109). And the control means 70 cancels | releases fixation of a compressor rotation speed (S110), drives the internal fan 6 (S111), and complete | finishes a defrost operation (S112).

  As described above, in the refrigerator configured as in the present embodiment, the first thermistor 61 is arranged at a position corresponding to the return port 46 on the upstream side of the air in the cooler 25. Further, the second thermistor 62 provided on the tray 29 is arranged at a position almost directly below the first thermistor 61. Then, the control means 70 determines that the frost on the cooler 25 and the tray 29 has been melted based on the detected temperatures of the first thermistor 61 and the second thermistor 62. Therefore, the refrigerator according to the present embodiment can reduce the power consumption during defrosting and the power consumption during pull-down while ensuring the defrosting reliability.

  1 Refrigeration room, 2 ice making room, 3 switching room, 4 freezing room, 5 vegetable room, 6 internal fan, 7 cooling room, 8 liquid receiving part, 9 drain pipe, 10 evaporating dish, 21 compressor, 22 channel switching Valve, 23 Condenser, 24 Capillary, 25 Cooler, 26 Header, 27 Bypass piping, 28 Tray piping, 29 Tray, 30 Drain hole, 41 Outlet, 42 Outlet, 43 Outlet, 44 Outlet, 45 Return port 46 Return port 61 First thermistor 62 Second thermistor 70 Control means.

Claims (6)

A storage room for storing objects to be cooled;
A cooling chamber provided with a cooler for cooling the air supplied to the storage chamber;
A blowout opening and a return opening are opened in the cooling chamber, and an air passage connecting the cooling chamber and the storage chamber;
An internal fan that causes the air cooled by the cooler to flow out from the outlet to the storage chamber, and causes the air that has flowed out of the storage chamber to flow into the cooling chamber from the return port;
A tray that is disposed below the cooler and receives frost and water sliding down from the cooler;
First heating means for heating the cooler;
A second heating means for heating the tray;
A first temperature detecting means provided in the cooler for detecting the temperature of the cooler;
A second temperature detection means provided on the tray for detecting the temperature of the tray;
Control means for determining the end of the defrosting operation by heating of the first and second heating means based on the detection results of the first and second temperature detection means,
The storage room has at least a refrigeration room,
As the return port, at least a first return port through which air that has flowed out of the refrigerator compartment flows into the cooling chamber,
The first temperature detection means is disposed at a position corresponding to the upstream side of the air flow in the cooler and the first return port,
The refrigerator, wherein the second temperature detecting means is disposed at a position almost directly below the first temperature detecting means. The storage room includes the refrigerator compartment and the freezer compartment,
As the return port, the first return port, and a second return port through which the air that has flowed out of the freezer compartment flows into the cooling chamber,
The first return port and the second return port are opened below the cooler on the front side surface of the cooling chamber,
The first return port is disposed above the second return port,
2. The refrigerator according to claim 1, wherein the first temperature detection unit is arranged in front of the center of the cooler in the front-rear direction of the refrigerator. The storage room includes the refrigerator compartment and the freezer compartment,
As the return port, the first return port, and a second return port through which the air that has flowed out of the freezer compartment flows into the cooling chamber,
The first return port and the second return port are opened below the cooler on the front side surface of the cooling chamber,
The first return port is disposed below the second return port,
2. The refrigerator according to claim 1, wherein the first temperature detection unit is disposed rearward of the center of the cooler in the front-rear direction of the refrigerator. The first return port is open at a position below the cooler on the front side surface of the cooling chamber,
At the position below the cooler on the front side surface of the cooling chamber, no return port other than the first return port is disposed above and below the first return port,
The first return port is arranged facing the cooler so that air flowing out of the refrigerator compartment flows directly into the cooler,
2. The refrigerator according to claim 1, wherein the first temperature detection unit is arranged in front of the center of the cooler in the front-rear direction of the refrigerator. The first return port is open at a position below the cooler on the front side surface of the cooling chamber,
At the position below the cooler on the front side surface of the cooling chamber, no return port other than the first return port is disposed above and below the first return port,
The first return port is arranged facing the tray so that air flowing out of the refrigerator compartment flows into the cooler via the tray,
2. The refrigerator according to claim 1, wherein the first temperature detection unit is disposed rearward of the center of the cooler in the front-rear direction of the refrigerator.   The first heating means and the second heating means are heated by a heating means for flowing and heating a heated fluid, a heating means for heating by a heater, or a heating means and a heater for flowing and heating a heated fluid. The refrigerator according to any one of claims 1 to 5, wherein the refrigerator includes both heating means.

Images