JP2018071874A - refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator improved in energy-saving performance by suppressing super heating while securing reliability by accurately detecting a melting state of frost growing in a cooler and a wall surface around the cooler.SOLUTION: A refrigerator includes: a food storage chamber; a compressor; a radiator heat-exchanging a coolant compressed with the compressor with outside air; a decompression means for decompressing the coolant; a cooler 21 heat-exchanging the decompressed coolant with air in the food storage chamber; a cooler storage chamber 9 storing the cooler 21; a draft air duct extending from the cooler storage chamber 9 to the food storage chamber; a return air duct extending from the food storage chamber to the cooler storage chamber 9; and an internal blower 22 blowing air heat-exchanged by the cooler 21 to the food storage chamber. There are arranged a first temperature sensor 44 detecting a temperature of the cooler 21, and a second temperature sensor 45 in the cooler storage chamber 9 at a downstream side than the cooler 21, or the draft air duct.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a refrigerator.

  As background arts in this technical field, there are, for example, Japanese Unexamined Patent Application Publication No. 2006-266617 (Patent Document 1) and Japanese Unexamined Patent Application Publication No. 2012-255572 (Patent Document 2).

  Generally, a refrigerator is a device that cools a storage room to a desired temperature by heat exchange between a cooler below freezing point and air in the cabinet, and frost grows on the surface of the cooler. The growth of frost causes an increase in thermal resistance and ventilation resistance, so the heat exchange performance in the cooler decreases as the frost grows. Therefore, a defrosting operation is performed in which frost is melted and removed in order to recover the heat exchange performance. The defrosting operation is performed by heating with a defrosting heater, and the completion of defrosting is determined by a temperature sensor.

  The refrigerator described in Patent Document 1 is provided with a defrost determination sensor, which is a temperature sensor, at a location behind the cooler of the inner box in the refrigerator main body. The end timing of the defrosting operation is determined by a defrosting determination sensor. That is, the defrosting determination sensor determines that the defrosting is completed when the surrounding area rises to a predetermined temperature, stops energization of the defrosting heater, and ends the defrosting operation.

  In addition, the refrigerator described in Patent Document 2 includes a cooler that generates cold air, a cool air duct in which the cooler is circulated through the cool air, and a cooler duct that is disposed below the cooler in the cool air duct to defrost the cooler. A defrosting heater, a temperature sensor that is disposed above the cooler and in the center of the cooler in the front-rear direction of the cooler, detects temperature and detects when the defrosting heater is stopped, and in front of the cooler duct It is provided on the wall and includes a holding unit that holds the temperature sensor. The holding unit covers the upper side of the temperature sensor. The defrosting heater is stopped when the temperature detected by the temperature sensor reaches a predetermined temperature.

JP 2006-266617 A JP 2012-255572 A

  Frost may grow not only on the cooler but also on the surrounding walls. In the prior art described in Patent Document 1 or Patent Document 2, the melting state of frost that has grown on the cooler and the wall surface around the cooler cannot be accurately detected. Must be set to a temperature sufficiently higher than the melting point of frost (ice). As a result, the energy-saving performance was not sufficiently high.

  The present invention has been made in view of the above problems, and by accurately detecting the melting state of the frost grown on the cooler and the wall surface around the cooler, energy saving performance that suppresses overheating while ensuring reliability. The purpose is to provide a high refrigerator.

  In order to solve the above problems, for example, the configuration described in the claims is adopted.

  The present application includes a plurality of means for solving the above-mentioned problems. For example, a food storage room, a compressor, a refrigerant compressed by the compressor, and a radiator that exchanges heat with air outside the warehouse. A decompression means for decompressing the refrigerant, a cooler for exchanging heat with the decompressed refrigerant and air in the food storage chamber, a cooler storage chamber for storing the cooler, and the cooler storage chamber from the cooler storage chamber An air passage leading to the food storage chamber, a return air passage extending from the food storage chamber to the cooler storage chamber, and an internal fan for blowing air exchanged with the cooler to the food storage chamber, A first temperature sensor for detecting the temperature of the cooler and a second temperature sensor are disposed in the cooler housing chamber or the air passage downstream of the cooler.

  According to the present invention, it is possible to provide a refrigerator with high energy saving performance by suppressing overheating while ensuring reliability by accurately detecting the melting state of the frost grown on the cooler and the wall surface around the cooler. Can do.

The front external view of the refrigerator which concerns on the embodiment of this invention. The AA arrow direction sectional view in Drawing 1 of the refrigerator concerning the example of an embodiment of the present invention. The figure showing the refrigerating cycle structure of the refrigerator which concerns on the example of embodiment of this invention. The expanded sectional view near the cooler of the refrigerator which concerns on the example of embodiment of this invention. BB arrow direction sectional drawing in FIG. 4 of the refrigerator which concerns on the embodiment of this invention. The flowchart showing control of the refrigerator which concerns on the embodiment of this invention. The time chart showing control of the refrigerator which concerns on the embodiment of this invention. The table | surface which shows the conditions with which the defrost start conditions of the refrigerator which concern on the example of embodiment of this invention are materialized.

  An embodiment of a refrigerator according to the present invention will be described with reference to FIGS. First, the structure of the refrigerator of the present embodiment will be described with reference to FIGS. FIG. 1 is a front outline view of a refrigerator according to the present embodiment, and FIG. 2 is a cross-sectional view illustrating a configuration inside the refrigerator of the present embodiment. A cross section AA shown in FIG. It is a figure. FIG. 3 is a diagram showing the refrigeration cycle configuration of the refrigerator of this embodiment. FIG. 4 is an enlarged cross-sectional view showing the configuration of the vicinity of the refrigerator cooler of the embodiment, and FIG. 5 is an enlarged cross-sectional view of the configuration of the vicinity of the refrigerator cooler of the embodiment, which is shown in FIG. It is the figure which looked at -B cross section in the arrow direction.

  As shown in FIG. 1, the refrigerator according to this embodiment includes a refrigerator body 1, a refrigerator compartment 2, an ice making compartment 4, an upper freezer compartment 5, a lower freezer compartment 6, and a vegetable compartment 8 from above. The ice making chamber 4 and the upper freezer compartment 5 are provided side by side between the refrigerator compartment 2 and the lower freezer compartment 6. The refrigerator compartment 2 and the vegetable compartment 8 are storage rooms in a refrigerator temperature zone of about 4 ° C. The ice making room 4, the upper freezing room 5 and the lower freezing room 6 are storage rooms having a freezing temperature range of about −18 ° C. (hereinafter, the ice making room 4, the upper freezing room 5, and the lower freezing room 6 are collectively frozen). Room 7).

  The refrigerating room 2 is provided with double door refrigerating room doors 2a and 2b that are divided into front and left sides. The ice making room 4, the upper freezing room 5, the lower freezing room 6, and the vegetable room 8 are provided with a drawer type ice making room door 4a, an upper freezing room door 5a, a lower freezing room door 6a, and a vegetable room door 8a, respectively. .

  As shown in FIG. 2, the outside of the refrigerator and the inside of the refrigerator of this embodiment are insulated by filling a foam insulation (foamed polyurethane) between the outer box 1a and the inner box 1b. 50. Moreover, the refrigerator of this embodiment is mounted with a vacuum heat insulating material 60 on the back and both sides (both sides are not shown).

  A plurality of door pockets 47 and a plurality of shelves 46 are provided in the refrigerator compartment 2 on the storage compartment side of the refrigerator compartment doors 2a and 2b. The ice making room 4, the upper freezing room 5, the lower freezing room 6 and the vegetable room 8 include a storage container 4b that moves in the front-rear direction integrally with the doors 4a, 5a, 6a, 8a provided in front of the respective storage rooms. , 5b, 6b, 8b. The doors 4a, 5a, 6a, and 8a can be pulled out of the storage containers 4b, 5b, 6b, and 8b by putting a hand on a handle portion (not shown) and pulling it out to the front side.

  As shown in FIG. 2, in the refrigerator of this embodiment, the refrigerator compartment 2, the upper freezer compartment 5, and the ice making room 4 (see FIG. 1) are separated by an upper heat insulating partition wall 51, and the lower freezer compartment 6 and the vegetable compartment. 8 is adiabatically separated by a lower heat insulating partition wall 52. Note that a chilled chamber 3 maintained at about −1 to + 1 ° C. is provided at the lowermost stage of the refrigerating chamber 2 (the upper portion of the upper heat insulating partition wall 51). In addition, a cooler storage chamber 9 is provided at the back of the freezer compartment 7, and a cooler 21 is provided in the cooler storage chamber 9 as a cooling means. In addition, an internal fan 22 is provided above the cooler 21 as a blowing means. The ventilation path to the refrigerator compartment 2, the freezer compartment 7, and the vegetable compartment 8 is provided with a refrigerator compartment damper 24, a freezer compartment damper 26, and a vegetable compartment damper (not shown), respectively, and the air supply to each compartment is controlled. .

  When the refrigerator compartment damper 24 is in an open state, the cold air boosted by the internal fan 22 flows through the refrigerator compartment air duct 11 and blows out from the refrigerator compartment outlet 31 to the refrigerator compartment 2. The cool air whose temperature has increased by cooling the refrigerator compartment 2 returns to the cooler storage chamber 9 via the refrigerator compartment return port (not shown) and the refrigerator compartment return duct 12 (see FIG. 5), and exchanges heat with the cooler 21. Then it becomes low temperature cold again.

  When the freezer compartment damper 26 is in an open state, the low-temperature cold air boosted by the internal fan 22 flows through the freezer compartment air duct 13 and blows out from the freezer compartment outlet 33 to the freezer compartment 7. The cool air whose temperature has risen by cooling the freezer compartment 7 returns to the cooler storage chamber 9 via the freezer return port 36 and exchanges heat with the cooler 21 to become low-temperature cool air again.

  When the vegetable room damper (not shown) is in an open state, the low temperature cold air pressurized by the internal fan 22 flows through the vegetable room air duct (not shown) and blows out from the vegetable room outlet (not shown) to the vegetable room 8. . The cool air whose temperature has risen by cooling the vegetable room 8 returns to the cooler storage room 9 via the vegetable room return port 37 and the vegetable room return duct 17 and exchanges heat with the cooler 21 to become low-temperature cold again.

  The back of the refrigerator compartment 2, the back of the freezer compartment 7, and the back of the vegetable compartment 8 are provided with a refrigerator compartment temperature sensor 41, a freezer compartment temperature sensor 42, and a vegetable compartment temperature sensor 43, respectively, for detecting the temperature of each compartment. It can be done. An outside temperature / humidity sensor (not shown) for detecting outside temperature / humidity is provided in front of the ceiling surface of the heat insulation box 50. The open / close states of the refrigerator compartment doors 2a and 2b, the ice compartment door 4a, the upper freezer compartment door 5a, the lower compartment freezer door 6a, and the vegetable compartment door 8 are the refrigerator compartment door sensor (not shown) and the ice compartment door. It can be detected by a sensor (not shown), an upper freezer compartment door sensor (not shown), a lower freezer compartment door sensor (not shown), and a vegetable compartment door sensor (not shown).

  An ice making water tank (not shown) for storing ice making water is provided at the left end of the area partitioned by the upper heat insulating partition wall 51. The water in the ice making water tank is supplied to an ice making tray (not shown) provided in the ice making chamber 4 through a pipe (not shown) by driving a pump (not shown).

  As shown in FIG. 3, the refrigeration cycle of the refrigerator of this embodiment includes a compressor 23, a radiator 70 (fin tube heat exchanger), a heat radiating pipe 71, a dew condensation suppression pipe 72, and a capillary tube 74 (hereinafter referred to as heat radiating). The condenser 70, the heat radiation pipe 71, and the dew condensation prevention pipe 72 may be collectively referred to as heat radiation means 73), and the cooler 21 is connected by the refrigerant pipe 77. A part 77a of the piping from the outlet of the cooler 21 to the compressor 23 is brought into contact with the capillary tube 74 to exchange heat. The heat radiating pipe 71 is a refrigerant pipe (not shown in FIG. 2) provided between the outer box 1a and the inner box 1b and in contact with the surface of the outer box 1a. Further, the dew condensation suppression pipe 72 is a refrigerant pipe (see FIG. 2) disposed on the front surface of the upper heat insulating partition wall 51, the front surface of the lower heat insulating partition wall 52, or the like of the heat insulating box 10, and the high temperature refrigerant flowing in the pipe. It is arranged to suppress dew condensation by the heating action.

  The high-temperature and high-pressure refrigerant pressurized by the compressor 23 flows through the heat dissipating means 73, dissipates heat, and is decompressed by a capillary tube as a decompression means, thereby becoming a low-temperature and low-pressure refrigerant. The low-temperature and low-pressure refrigerant flows into the cooler 21, and low-temperature cold air for cooling each storage chamber is generated by exchanging heat with air. The refrigerant will be described using isobutane as an example.

  As shown in FIG. 4, the cooler storage chamber 9 is formed between the inner box 1b on the back side and the front partition wall 27 on the front side. The cooler 21 housed in the cooler storage chamber 9 is a finned tube heat exchanger having seven stages in the flow direction and a depth dimension D smaller than the height dimension H (in the refrigerator of this embodiment, H = 210 mm, D = 77 mm). Thus, by making the depth dimension D smaller than the height dimension H, the effective internal volume of the storage chamber (freezer compartment 7 in the refrigerator of the present embodiment) in front of the cooler housing chamber 9 can be increased.

  A bypass channel 55 a is provided between the front partition wall 27 and the cooler 21 on the front side below the cooler 21, and a bypass channel 55 b is provided between the inner box 1 b and the cooler 21 on the rear side. . In the refrigerator 1 of the present embodiment, the channel width L1 of the bypass channel 55a is 5 mm, and the channel width L2 of the bypass channel 56b is 7 mm. As described above, since the flow path width of the bypass flow path is 10% or less of the depth dimension D (= 77 mm) of the cooler, a large amount of airflow is cooled in a state where the amount of frost on the cooler 21 is small. The cooling efficiency decline by flowing by bypassing the vessel 21 can be suppressed.

  As shown in FIG. 5, the refrigerator 1 according to this embodiment includes a defrost heater 56 below the cooler 21. Here, the width dimension W2 of the defrost heater 56 is made longer than the width dimension W1 of the fin installation part 21a of the cooler 21 (W2> W1). Thereby, the whole cooler 21 can be efficiently heated. In the refrigerator 1 of the present embodiment, W1 = 335 mm and W2 = 350 mm.

  The defrosting heater 56 covers the resistance wire with the glass tube 56a, and further, by disposing aluminum radiating fins 56b on the outer periphery of the glass tube 56a, the surface temperature of the glass tube becomes the ignition temperature of isobutane during energization of the defrosting heater. The temperature is lower than (about 460 ° C.).

  The defrost water generated by the melting of the frost flows down to the trough 57 provided at the lower part of the cooler housing chamber 9 and is provided in the machine room 10 (see FIG. 2) through the drain pipe 58 (see FIG. 2). The obtained evaporating dish 59 (see FIG. 2) is reached. The defrosted water in the evaporating dish 59 is discharged from the compressor 23 (see FIG. 2) and the radiator 70 (see FIG. 3) provided in the machine room 10 and the outside fan provided in the machine room 10. It evaporates due to the ventilation effect (not shown). An upper cover 53 is provided on the upper portion of the defrost heater 56 to prevent molten water or frost released from the cooler 21 from hitting the glass tube 56 a of the defrost heater 56.

The fin pitch of the first stage (uppermost stage) of the cooler 21 is larger than the fin pitch of the second stage and subsequent stages (2 to 7 stages) (in the refrigerator 1 of the present embodiment, the first stage). The fin pitch is 10 mm, and the 2nd to 7th fin pitch is 5 mm). Since the first stage of the cooler 21 has a high mass transfer rate and high humidity air flows in, frost is likely to grow. The heat exchange performance can be maintained for a longer time. In order to make the flow path between the fins difficult to block, at least the fin pitch of the most upstream stage (first stage) is set to the fin of the most downstream stage (seventh stage in the refrigerator 1 of the present embodiment). The pitch may be greater than or equal to the pitch, and is not limited to the configuration of the present embodiment.
The low-temperature and low-pressure refrigerant depressurized by the capillary tube 74 (see FIG. 3) enters from the upper pipe on the back side of the cooler 21 and sequentially flows from the upper side to the lower side on the rear side of the cooler 21. The first stage (bottom stage) moves to the pipe on the front side of the cooler 21. Subsequently, the pipes provided on the left and right sides on the front side of the cooler 21 sequentially flow from the bottom to the top and flow out from the front side upper part of the cooler 21. The outlet pipe of the cooler 21 is provided with a gas-liquid separator 28 to prevent liquid refrigerant from being sucked into the compressor 23 and compressed.

  The return air from the refrigerator compartment 2 flows through the refrigerator compartment return duct 12 and flows into the cooler storage chamber 9 from the lower side of the cooler 21 through the refrigerator compartment return duct opening 12a. Return air from the freezer compartment 7 flows into the cooler storage chamber 9 from the freezer compartment return port 36 (see FIG. 4) in front of the lower portion of the cooler 21. The return air from the vegetable compartment 8 is stored in the cooler through the vegetable compartment return duct opening 17a on the lower front right side (left side when viewed from the front) of the cooler 21 via the vegetable compartment return duct 17 (see FIG. 2). It flows into the chamber 9.

  In the refrigerator 1 of this embodiment, the ratio of the amount of air sent to the refrigerator compartment 2 and the vegetable compartment 8 in the refrigerated temperature zone and the amount of air sent to the freezer compartment 7 in the freezer temperature zone is about 3: 7, and is kept at a low temperature. The amount of air blown to the freezer compartment 7 is increased. Further, by making the opening width W3 of the freezer compartment return port 36 larger than the width dimension W1 of the fin installation portion 21a of the cooler 21 (W3> W1), the return air from the freezer compartment 7 having a particularly large air flow rate. However, heat can be efficiently exchanged by the cooler 7.

  Moreover, the refrigerator 1 of this embodiment provides the refrigerator compartment return duct opening 12a on the right (left when viewed from the front) of the center surface S1 of the width W1 of the cooler 21 (the width of the fin installation portion). The chamber return duct opening 17a is provided to the left of the center plane S1 (right when viewed from the front). As a result, the occurrence of uneven frost formation in the cooler 21 is suppressed.

  An internal fan 22 is installed above the cooler 21 and its installation position is made to substantially coincide with the center plane S1. Specifically, the center surface S1 of the cooler passes through the range of the blade width W4 of the internal fan 22. This makes it difficult for the cool air flow in the cooler 21 to be biased.

  On both sides of the cooler 21, the return air does not flow into the fin installation part 21a of the cooler 21, but flows through the pipe turn parts 21b on both sides of the cooler 21, or the air flowing into the fin installation part 21a flows into the pipe turn. A cooler channel partition member 21c (made of aluminum) is provided for suppressing leakage to the portion 21b. Thereby, the heat exchange efficiency between the cooler 21 and air is improved.

  A suction pipe (on the left side when viewed from the front) of the upper side of the cooler 21 on the right side of the center plane S1 is provided with a cooler temperature sensor 44 (first defrosting completion detecting means), which controls the temperature of the cooler. It can be detected. Further, a front partition wall temperature sensor for detecting the temperature of the front partition wall in the vicinity of the internal fan 22 is provided on the surface of the front partition wall 27 on the left side (right side when viewed from the front) of the center plane S1 downstream of the cooler 21. 45 (second defrosting completion detecting means) is provided. In the refrigerator 1 of the present embodiment, the temperature detected by the front partition wall temperature sensor 45 when defrosting is completed (heater energization is completed) and the surface temperature of the mouth ring 22a of the internal fan 22 are within 3 ° C. A front partition wall temperature sensor 45 is provided at the matching position.

  The refrigerator 1 according to this embodiment includes a refrigerator compartment 2 (see FIG. 2), a vegetable compartment damper (not shown), a freezer compartment damper 26 (see FIG. 2), and a refrigerator compartment 2, a vegetable compartment 8, and a freezer compartment. 7 is controlled, “cooling room single operation” to blow only to the refrigerator room, “vegetable room single operation” to blow only to the vegetable room, “freezer room single operation” to blow only to the freezer room, There are five cooling operation modes: “refrigerated vegetable operation” for blowing air to the vegetable room, and “refrigerated vegetable freezing operation” for airing all of the refrigerator room, vegetable room, and freezer room. In each of the refrigerator compartment 2, the vegetable compartment 8, and the freezer compartment 7, these five cooling operation modes are appropriately switched based on the detection information of the refrigerator compartment temperature sensor 41, the vegetable compartment temperature sensor 43, and the freezer compartment temperature sensor 42. Thus, the desired temperature range is maintained.

  The refrigerator according to this embodiment includes a temperature setting device (not shown) for setting the temperatures of the refrigerator compartment 2, the chilled compartment 3, the freezer compartment 7, and the vegetable compartment 8.

  A control board 49 on which a CPU, a memory such as a ROM and a RAM, an interface circuit, and the like are mounted is disposed on the top surface of the refrigerator body 1 (see FIG. 2). The control board 49 includes the refrigerator compartment temperature sensor 41, the freezer compartment temperature sensor 42, the vegetable compartment temperature sensor 43, the outside temperature and humidity sensor, the cooler temperature sensor 44, the front partition wall temperature sensor 45, and each door sensor. It is connected to a temperature setter provided in the refrigerator compartment door 2aa. ON / OFF of compressor 23, rotation speed control, control of actuator (not shown) for individually driving refrigerator compartment damper 24, freezer compartment damper 26, and vegetable compartment damper 27, ON / OFF control of internal fan 22 Further, control such as rotation speed control and ON / OFF of an alarm for notifying the door open state described above is performed by a program preinstalled in the ROM.

  Next, control of the refrigerator according to the present embodiment will be described with reference to FIGS. FIG. 6 is a flowchart showing the control of the refrigerator of this embodiment, and FIG. 7 is a time chart showing the control of the refrigerator of this embodiment. FIG. 8 is a table showing conditions for satisfying the defrosting start condition.

  As shown in FIG. 6, the refrigerator of the present embodiment starts the cooling operation by driving the compressor 23 when the power is turned on (start) (step S101).

  The cooling operation of the refrigerator according to the present embodiment is performed by the compressor 23, the internal fan 22, and the refrigerator based on the detection information of the refrigerator compartment temperature sensor 41, the freezer compartment temperature sensor 42, the vegetable compartment temperature sensor 43, and the outside temperature and humidity sensor. Each room is set to a set temperature (for example, about 4 ° C. in the refrigerator room and vegetable room) by controlling the on / off control and rotation speed control of the external blower and the open / close state of the refrigerator compartment damper 24, freezer compartment damper 26 and vegetable compartment damper. The operation of maintaining the freezing room at about −18 ° C. is performed.

  During the cooling operation, the defrosting start condition is determined (step S102). In the refrigerator 1 of the present embodiment, the defrosting start condition is satisfied when the condition shown in FIG. 8 is satisfied (Yes in step S102). If step S102 is not established, the cooling operation is continued (return to step S101).

  For example, (a) When the outside temperature (Tout) is Tout> 35 ° C., the outside humidity (relative humidity) (RHout) is RHout ≦ 50%, the door opening / closing cumulative time (t1) is t1 ≧ 20 minutes, and the cooling operation is continued. When the time (t2) (elapsed time since the completion of the previous defrosting, or the elapsed time since the power was turned on when the defrosting operation has not been performed) is t2 ≧ 12 hours, or the cooling operation duration (t2 ) Is satisfied when any of t2 ≧ 48 hours is satisfied. The other conditions are as follows: (b) When Tout> 35 ° C. and 50 <RHout ≦ 80%, when either t1 ≧ 15 minutes and t2 ≧ 12 hours or t2 ≧ 48 hours is satisfied, (c) When either T1 ≧ 10 minutes and t3 ≧ 12 hours or t2 ≧ 48 hours is satisfied at Tout> 35 ° C. and RHout> 80%, (d) 20 ° C. <Tout ≦ 35 ° C., RHout ≦ 50 %, When either t1 ≧ 25 minutes and t2 ≧ 12 hours or t2 ≧ 72 hours are satisfied, (e) at 20 ° C. <Tout ≦ 35 ° C., 50 <RHout ≦ 80%, t1 ≧ 20 Minutes and t3 ≧ 12 hours, or t2 ≧ 72 hours, (f) t1 ≧ 15 minutes and t3 ≧ 12 hours at 20 ° C. <Tout ≦ 35 ° C. and RHout> 80%. If any of t2 ≧ 72 hours is satisfied, (g) At Tout ≦ 20 ° C. and RHout ≦ 50%, either t1 ≧ 50 minutes and t3 ≧ 12 hours or t2 ≧ 96 hours is satisfied When (h) Tout ≦ 20 ° C. and 50 <RHout ≦ 80%, either t1 ≧ 40 minutes and t3 ≧ 12 hours or t2 ≧ 96 hours are satisfied, (i) Tout ≦ This is a case where t1 ≧ 30 minutes and t3 ≧ 12 hours or t2 ≧ 96 hours are satisfied at 20 ° C. and RHout> 80%.

  The refrigerator 1 of the present embodiment includes three defrosting means (defrosting means 1, defrosting means 2, and defrosting means 3). The first defrosting means (defrosting means 1) is for defrosting while cooling the refrigerator compartment and the vegetable compartment by driving the internal blower 22, and "compressor stopped state, internal blower drive" Frost is defrosted in the "state, defrost heater stopped state, refrigerator compartment damper open state, vegetable compartment damper open state, freezer compartment damper closed state". The second defrosting means (defrosting means 2) drives the internal blower 22 with the defrosting heater 56 energized to defrost while cooling the refrigerator compartment and the vegetable compartment. The frost is released in the "state, fan operation state in the refrigerator, defrost heater energized state, refrigerator compartment damper open state, vegetable compartment damper open state, frozen greenhouse damper closed state". The third defrosting means (defrosting means 3) performs defrosting only by energization of the defrosting heater 22, and “compressor stopped state, internal fan stop state, defrosting heater energized state, refrigerator compartment” The frost is defrosted when the damper is closed and the freezer damper is opened.

  The refrigerator 1 of the present embodiment includes two defrosting modes of “energy saving defrosting mode” for sequentially switching the defrosting means 1 to 3 and “high reliability defrosting mode” by only the defrosting means 3. When (d), (e), (g), (h), and (i) in FIG. 8 are established, “energy saving defrosting mode”, and (a), (b), (c), and (f) are established. “Reliable defrosting mode” is selected.

  In the case of “energy saving defrost mode” (No in step S103), then “compressor driving state, internal fan driving state, defrosting heater stopped state, refrigerator compartment damper closed state, vegetable compartment damper closed state, freezer compartment damper The freezer compartment pre-cooling operation is performed in the “open state” (step S104). As a result, the freezer compartment 7 that is not cooled during the defrosting can be sufficiently cooled in advance, and it becomes difficult to cause problems such as freezing of frozen food and ice during the defrosting.

  After the freezer compartment pre-cooling operation is performed for a predetermined time (30 minutes in the refrigerator 1 of the present embodiment), the defrosting means 1 (compressor stopped state, internal fan drive state, defrost heater stopped state, refrigerator compartment damper opened) The defrosting operation is performed according to the state, the vegetable room damper open state, and the freezer compartment damper closed state (step S105). When the detected temperature TD1 of the cooler temperature sensor 44 reaches −3 ° C. (step S106), the defrosting means 2 (compressor stopped state, internal fan drive state, defrost heater energized state, refrigerator compartment damper open state, vegetable) The operation proceeds to the defrosting operation in the room damper open state and the freezing greenhouse damper closed state (step S107). When the detected temperature TD1 of the cooler temperature sensor 44 reaches + 2 ° C. (step S108), the defrosting means 3 (compressor stopped state, internal fan stop state, defrost heater energized state, refrigerator compartment damper closed state, freezing) The operation proceeds to the chamber damper open state (step S109). Defrosting by the defrosting means 3 is determined as defrosting completion when the detected temperature TD1 of the cooler temperature sensor 44 is + 5 ° C. or higher and the detected temperature TD2 of the front partition wall temperature sensor 45 is + 3 ° C. or higher. (Step S110), in order to encourage drainage of the molten water in the cooler storage chamber 9, "compressor stopped state, internal fan stop state, defrost heater stopped state, refrigerator compartment damper open state, vegetable compartment damper open state, A “off time” for setting the “freezer compartment damper open state” is secured for a predetermined time (3 minutes in the refrigerator 1 of the present embodiment) (step S111). The determination of the completion of defrosting is sufficient if the condition that “the detected temperature TD1 of the cooler temperature sensor 44 and the detected temperature TD2 of the front partition wall temperature sensor 45 are both higher than 0 ° C.” is satisfied. The temperature may be different from that of the refrigerator 1 of the embodiment. However, by making the determination reference temperature of the front partition wall temperature sensor 45TD2 far from the defrost heater 56 lower than the detection temperature TD1 of the cooler temperature sensor 44, overheating can be suppressed and energy saving performance is improved. be able to.

  Subsequently, in order to avoid high temperature air being blown into the storage room, the compressor is driven while the internal fan 22 is stopped, “compressor stopped drive state, internal fan stop state, defrost heater stopped state, refrigeration “Cavity fan damper open state, vegetable compartment damper open state, freezer compartment damper open state” for “cooling in the refrigerator storage chamber 9” for cooling the inside of the cooler storage chamber 9 for a predetermined time (in the refrigerator 1 of this embodiment) After 2 minutes (step S112), the cooling operation is restarted (step S101).

  When “high reliability defrosting mode” is established in step S103 (Yes in step S103), “compressor driving state, internal fan driving state, defrosting heater stopped state, refrigerator freezer state, vegetable All-room precooling operation is performed in the “room damper open state, freezer compartment damper open state” (step S201). In the “high reliability defrosting mode”, the storage room is not cooled during the defrosting operation, but the freezing room 7 that is not cooled during the defrosting can be sufficiently cooled in advance by the precooling of all the rooms. It is possible to prevent the temperature of each storage room from rising excessively.

  After performing the all-room precool operation for a predetermined time (30 minutes in the refrigerator 1 of the present embodiment), the process proceeds to step S109, and the defrosting means 3 (compressor stopped state, internal fan stop state, defrost heater energized state, The defrosting operation is performed in the refrigerator compartment damper open state, the vegetable compartment damper open state, and the freezer compartment damper open state. Thereafter, the control steps are the same as those in the “energy saving defrost mode”.

  FIG. 7 is a time chart showing the control state and the temperature change in the main part of the refrigerator when the refrigerator is installed in a room at 32 ° C. and a relative humidity of 70%.

As shown in FIG. 7, is satisfied defrosting start condition is at the elapsed time t _a (cooling operation continuation time t2 reaches 48h here, defrosting operation start conditions are satisfied (in FIG. 8 (e) 5 is Yes depending on the conditions.) When (d), (e), (g), (h), and (i) in FIG.8 are established, the “energy saving defrosting mode” is selected (step in FIG. 6). S103 is No), followed by freezer compartment precool operation in "compressor drive state, internal fan drive state, defrost heater stop state, refrigerator compartment damper closed state, vegetable compartment damper closed state, freezer compartment damper open state" 6 (step S104 in FIG. 6), the freezer compartment 7 is cooled and the temperature is lowered, and the temperatures of the refrigerator compartment 2 and the vegetable compartment 8 that are not cooled are raised.

In the elapsed time tb, the freezer compartment precooling operation continuation time (30 minutes) has elapsed, and the defrosting means 1 (compressor stopped state, internal fan drive state, defrost heater stopped state, refrigerator compartment damper open state, vegetable compartment damper open) The defrosting operation is performed according to the state (freezer compartment damper closed state) (step S105 in FIG. 6). In the defrosting by the defrosting means 1, the internal fan 22 is controlled so as to cool the refrigerator compartment 2 and the vegetable compartment 8 mainly by air exchanged with sensible heat of the frost (specifically, driven at 1500 min ⁻¹ ). Therefore, the temperature of the refrigerator compartment 2 and the vegetable compartment 8 during the defrosting by the defrosting means 1 is falling. This is a defrosting with high energy saving performance because the frost is heated by the heat load in the cabinet without using a heater.

At the elapsed time tc, the detection temperature TD1 of the cooler temperature sensor 44 reaches −3 ° C. (Yes in step S106 in FIG. 6), and the defrosting means 2 (compressor stopped state, internal fan drive state, defrost heater) Transition to defrosting by energized state, refrigerator compartment damper open state, vegetable compartment damper open state, frozen greenhouse damper closed state (step S107 in FIG. 6). In the defrosting by the defrosting means 2, the defrosting heater 56 is energized to accelerate the defrosting, and the air is mainly heat-exchanged with the latent heat of the frost (cooler temperature (frost temperature) is almost constant at 0 ° C). Therefore, the defrost heater and the internal fan 22 are controlled so as to cool the refrigerator compartment 2 and the vegetable compartment 8 (specifically, the defrost heater energization amount is 150 W and the internal fan rotational speed is driven at 1200 min ⁻¹ ). The temperature of the refrigerator compartment 2 and the vegetable compartment 8 during the defrosting by the defrosting means 2 is maintained. The refrigerator compartment 2 and the vegetable compartment 8 during the defrosting by the defrosting means 2 are maintained by being cooled. This is because the frost is heated using the heat load in the cabinet while the heater is energized, so energy saving performance is high, and the amount of heat necessary for melting the frost can be given in a relatively short time. It becomes possible.

  At the elapsed time td, the detected temperature TD1 of the cooler temperature sensor 44 reaches + 2 ° C. (Yes in step S108 in FIG. 6), and the defrosting means 3 (compressor stopped state, internal fan stop state, defrost heater energized) The process is shifted to defrosting by the state, the refrigerator compartment damper closed state, and the freezer compartment damper opened state (step S109 in FIG. 6). Since the defrosting means 2 performs defrosting only by energizing the defrosting heater 56, the refrigerator compartment 2, the vegetable compartment 8, and the freezer compartment 7 are not cooled and the temperature rises. Moreover, since the cooler temperature is heated by the defrost heater 56, the temperature rises. Further, the detected temperature TD2 of the front partition wall temperature sensor 45 is about 0 ° C. at the elapsed time td, but starts to rise to a positive temperature during the defrosting operation by the defrosting means 3.

  At the elapsed time te, the detection temperature TD1 of the cooler temperature sensor 44 reaches + 6 ° C., the detection temperature TD2 of the front partition wall temperature sensor 45 reaches + 3 ° C. (step S110 in FIG. 6 is Yes), and the defrost heater 56 Energization is stopped, and it is shifting to “off time (compressor stopped state, internal fan stop state, defrost heater stopped state, refrigerator compartment damper open state, vegetable compartment damper open state, freezer compartment damper open state)” (Step S111 in FIG. 6).

  Further, at the elapsed time tf, when the set time (3 minutes) of “off time” has elapsed, the compressor 23 is driven in the state where the internal fan 22 is stopped, “the internal fan stop operation (compressor stop driving state, It has shifted to “inside fan stop state, defrost heater stop state, refrigerator compartment damper open state, vegetable compartment damper open state, freezer compartment damper open state” ”(step S112 in FIG. 6).

  Since the refrigerator compartment 2, the vegetable compartment 8, and the freezer compartment 7 are not cooled during "off time" to "internal fan stop operation", the temperature rises. On the other hand, the cooler temperature and the front partition wall surface temperature rise during the “off-time”, but in “internal fan stop operation”, low-temperature refrigerant flows through the cooler, so the cooler temperature and front partition wall surface temperature are It is falling.

  When the set time (2 minutes) of “internal fan stop operation” has elapsed at the elapsed time tg, the internal fan 22 is driven and the cooling operation (freezing operation) is resumed (step S101 in FIG. 6). ).

  As described above, the refrigerator of the present embodiment includes the temperature sensor (front partition wall temperature sensor 45) that detects the temperature of the partition wall surface inside the warehouse of the downstream flow path of the cooler 21, and the detection information includes Based on this, the defrosting completion is determined. Among the wall surfaces forming the cool air flow path, the wall surface located outside the refrigerator (for example, the back surface of the cooler storage chamber 9 in the refrigerator 1 of the present embodiment) rises in temperature due to heat intrusion from outside the refrigerator during the defrosting operation. Although it is easy, the wall surface located on the inner side (wall surface that forms the boundary between the storage room and the air channel) is unlikely to rise in temperature due to the low temperature storage room. In general, in the defrosting operation in a refrigerator, since it is determined that the defrosting is completed when it is estimated that the frost in the cooler and its surroundings has melted, the installation position of the defrosting completion detection means (temperature sensor) It is desirable to install in places that are difficult to unravel. The refrigerator according to the present embodiment includes a temperature sensor (front partition wall temperature sensor 45) that detects the temperature of the partition wall surface inside the refrigerator downstream of the cooler 21, where the temperature is difficult to rise, and removes the temperature based on the detected information. Judge the completion of frost. Thereby, since the temperature of the location where frost is hard to be melted can be detected, the defrosting operation can be performed without setting the defrosting completion determination reference temperature having an excessive margin. Therefore, it is possible to provide a refrigerator that has both high energy saving performance and high reliability.

  The refrigerator of this embodiment includes a temperature sensor (cooler temperature sensor 44) that detects the cooler temperature and a temperature sensor (front partition wall temperature sensor 45) that detects the temperature of the downstream flow path of the cooler 21. The defrosting completion is determined based on the detection information of these sensors. Specifically, it is determined that the defrosting is completed when both the detection temperature TD1 of the cooler temperature sensor 44 and the detection temperature TD2 of the front partition wall temperature sensor 45 reach a predetermined temperature higher than 0 ° C. A cooler temperature sensor 44 (first defrosting completion detection means) and a front partition wall temperature sensor 45 (second defrosting completion detection means) are provided, and the surface temperature of the first defrosting completion detection means, If the defrosting operation (heater energization) is terminated when the surface temperature of the second defrosting completion detection means reaches a predetermined temperature higher than 0 ° C., the detection temperature of the first defrosting completion detection means and the second defrosting detection means It can be regarded as control based on the detection information of the detection temperature of the frost completion detection means.

  As a result, it is not necessary to have an excessive margin in the defrosting completion criterion value for both the cooler in which frost easily grows and the downstream flow path of the cooler in which the temperature does not easily rise, and overheating can be suppressed. . Therefore, it is possible to provide a refrigerator with high energy saving performance and high reliability.

  Generally, the state of frost formation on the refrigerator cooler and the surroundings of the refrigerator varies depending on the operation history of the refrigerator, the type and amount of food stored in the refrigerator, the frequency of opening and closing the door, and so on. The amount of frost formed on the cooler and the amount of frost formed on the downstream of the cooler are not constant. Therefore, in the conventional refrigerator, since the defrost completion is judged by the single defrost completion detection means for detecting the defrost state of the cooler, the most severe condition in reliability, that is, the temperature of the cooler is increased. Therefore, it was necessary to set a judgment reference value assuming a condition in which frost is likely to remain in the cooler downstream flow path.

  The temperature of the cooler tends to rise, and frost tends to remain in the cooler downstream flow path when there is relatively little frost formation on the cooler and there is a lot of frost formation in the cooler downstream flow path. Yes, when the defrosting completion is determined only by the cooler temperature sensor 44, as a determination reference value that can be sufficiently melted even if a large amount of frost is formed in the downstream flow path of the cooler, for example, about 10 ° C. It was necessary to. On the other hand, in the refrigerator of this embodiment, since the defrosting completion is determined based on the detection temperature of the first defrosting completion detection means and the detection information of the detection temperature of the second defrosting completion detection means, The frost formation of the cooler is relatively low, and a lot of frost is generated in the cooler downstream flow path. Conditions other than the most severe conditions, for example, the cooler is frosted frequently and the cooler downstream flow path is frosted. Overheating of the cooler can be suppressed under conditions where there is little or no frost formation on the cooler and the downstream flow path of the cooler. For example, in the refrigerator of the present embodiment, at the time when it is determined that the defrosting of the downstream flow path of the cooler has been completed (the detection temperature of the front partition wall temperature sensor 45 is 3 ° C.), the cooler temperature (cooler temperature) The detected temperature of the sensor 44 is 6 ° C., and it can be seen that overheating of the cooler is suppressed. The refrigerator of this embodiment includes a temperature sensor (cooler temperature sensor 44) that detects the cooler temperature and a temperature sensor (front partition wall temperature sensor 45) that detects the temperature of the downstream flow path of the cooler 21. In addition, at least one temperature detection means is disposed in both of the regions that are divided with reference to the center plane in the width direction of the cooler 21.

  Thereby, in the cooler storage chamber 9, the defrost state of both the cooler in which frost easily grows and the downstream flow path of the cooler in which the temperature hardly rises can be detected efficiently.

  In the refrigerator of the present embodiment, a temperature sensor (front partition wall temperature sensor) detects the temperature of the partition wall surface using the temperature in the vicinity of the movable part (internal fan 22) installed in the downstream flow path of the cooler 21. 45). As a result, it is possible to suppress the risk of frost remaining undissolved in the vicinity of the movable part (internal fan 22) in the downstream flow path of the cooler, where the temperature does not easily rise. It is not necessary to have a margin, and overheating can be suppressed.

  Therefore, it is possible to provide a refrigerator that has both high energy saving and high reliability.

  In addition, this invention is not limited to each above-mentioned Example, Various modifications are included. For example, a plurality of temperature sensors that detect the temperature of the cooler 21 and a plurality of temperature sensors that detect the temperature of the downstream flow path of the cooler 21 may be provided. Moreover, in the refrigerator 1 of this embodiment, although the temperature of the internal fan 22 is detected as a movable part in the downstream flow path of the cooler 21, as another movable part in the downstream flow path of the cooler 21, for example, You may arrange | position the temperature sensor which detects damper temperature (temperature vicinity of a damper). Furthermore, the temperature sensor is directly arranged on the working part held on the wall surface located inside the warehouse of the downstream flow path of the cooler 21 to measure the temperature of the movable part, or the temperature of the movable part increases. An auxiliary heater may be provided at a difficult place to heat the defrosting operation. In addition, the refrigerator 1 of the present embodiment has five types of cooling operation modes of “cold room independent operation”, “vegetable room independent operation”, “freezer compartment independent operation”, “refrigerated vegetable operation”, and “refrigerated vegetable freezing operation”. Although it is a refrigerator equipped with, it does not need to be equipped with all of these.

  That is, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described.

DESCRIPTION OF SYMBOLS 1 Refrigerator body 2 Refrigeration room 3 Chilled room 4 Ice making room 5 Upper freezing room 6 Lower freezing room 7 Freezing room 8 Vegetable room 9 Cooler storage room 10 Machine room 11 Refrigeration room air duct 12 Refrigeration room return duct 13 Freezer room air duct 17 Vegetable room return duct 21 Cooler 22 Internal fan 23 Compressor 24 Refrigeration room damper 26 Freezer compartment damper 27 Front partition wall 28 Gas-liquid separator 31 Refrigeration room outlet
33 Freezer compartment outlet 36 Freezer compartment return port 37 Vegetable room return port 41 Refrigerator room temperature sensor 42 Freezer room temperature sensor 43 Vegetable room temperature sensor 44 Cooler temperature sensor 45 Front partition wall temperature sensor 46 Shelf 47 Door pocket 49 Control board 50 Heat insulation box 51 Upper heat insulation partition wall (partition)
52 Lower heat insulation partition wall (partition)
55aa, 55b Bypass passage 56 Defrost heater 57 樋 58 Drain pipe 59 Evaporating dish 60 Vacuum heat insulating material 70 Heat radiation means 71 Radiator 72 Heat radiation pipe 73 Condensation suppression pipe 74 Capillary tube 77 Refrigerant piping

Claims (5)

  A food storage chamber; a compressor; a heat exchanger exchanging heat with the refrigerant compressed by the compressor and air outside the storage; a decompression means for decompressing the refrigerant; the decompressed refrigerant and the food storage chamber; A cooler for exchanging heat with air, a cooler storage chamber for storing the cooler, an air passage from the cooler storage chamber to the food storage chamber, and a return from the food storage chamber to the cooler storage chamber An air passage, and an internal fan that blows air exchanged by the cooler to the food storage room, a first temperature sensor that detects a temperature of the cooler, and the downstream of the cooler A refrigerator characterized in that a second temperature sensor is disposed in a cooler storage chamber or the air passage.   2. The refrigerator according to claim 1, wherein the defrosting operation is terminated when both of the first temperature sensor and the second temperature sensor have reached a predetermined temperature of 0 ° C. or more.   The at least one first temperature sensor is disposed on one side and the at least one second temperature sensor is disposed on the other side with respect to the center plane in the width direction of the cooler. The refrigerator according to claim 1 or 2, wherein the refrigerator is characterized.   The refrigerator according to any one of claims 1 to 3, wherein the second temperature sensor is disposed in a main body of the movable part or a region near the movable part.   A food storage chamber; a compressor; a heat exchanger exchanging heat with the refrigerant compressed by the compressor and air outside the storage; a decompression means for decompressing the refrigerant; the decompressed refrigerant and the food storage chamber; A cooler for exchanging heat with air, a cooler storage chamber for storing the cooler, an air passage from the cooler storage chamber to the food storage chamber, and a return from the food storage chamber to the cooler storage chamber A refrigerator comprising: an air passage, wherein a temperature sensor is disposed on a wall surface on the inner side among the wall surfaces forming the cooler housing chamber or the air passage, downstream of the cooler.

Images