JP2016044899A - refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator improving accuracy of detecting the fact that a heater is normally controlled.SOLUTION: A refrigerator includes: a first control mode that in a case of controlling a pipe heater 41 and a radiant heater 20 into a non-electrification state, when a cooler temperature sensor detects predetermined temperature rise, determines that a pipe heater circuit is made into an error electrification state; and a second control mode that in a case of controlling the pipe heater 41 into an electrification state, when the cooler temperature sensor does not detect the predetermined temperature rise, determines that the pipe heater circuit is made into a disconnection state.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a refrigerator.

  As a prior art in this technical field, for example, there is JP 2011-7435 A (Patent Document 1).

  In the summary column of this patent document 1, “the refrigerator is disposed below the cooler 24, the cooler 24 that is a part of the refrigeration cycle, the pipe heater 41 that directly melts the frost attached to the cooler 24,” A radiant heater 15 that melts frost from below, and a control means (not shown) that controls energization of the pipe heater 41 and the radiant heater 15, and the control means starts energization of the pipe heater 41. Then, energization of the radiant heater 15 is started and the cooler 24 is defrosted. "

JP 2011-7435 A

  However, when an abnormality or failure occurs in either the radiant heater or the pipe heater, predetermined defrosting performance and cooling performance may not be obtained. Patent Document 1 describes defrosting using a radiant heater and a pipe heater, but does not mention any means for detecting abnormality (failure) of the heater or heater circuit. Since the radiant heater is defrosted by radiant heat, it is possible to protect against an abnormality (failure) of the radiant heater circuit by a temperature fuse generally provided as a protection device in the cooler or in the vicinity of the cooler. However, pipe heaters that are defrosted by direct heat transfer to the cooler have a small temperature effect on the thermal fuse, so even if an abnormality (failure) occurs in the pipe heater circuit, the pipe heater circuit malfunctions (failure) ) May be difficult to protect.

  Accordingly, an object of the present invention is to provide a refrigerator that further improves the accuracy of detecting that the heater is normally controlled.

  In order to solve the above-described problems, the refrigerator of the present invention includes, as an example, a cooler, a radiant heater below the cooler, a pipe heater disposed in contact with or close to the cooler, and the cooler. And a controller for controlling energization of the radiant heater and the pipe heater, and the control unit controls the pipe heater and the radiant heater in a non-energized state. A first control mode for determining that the pipe heater circuit is in error energization when the cooler temperature sensor detects a predetermined temperature rise, and the pipe heater is controlled to be energized. And a second control mode for determining that the pipe heater circuit is disconnected when the cooler temperature sensor does not detect a predetermined temperature rise. And butterflies.

  The refrigerator which further improved the precision which detects that the heater is controlled normally can be provided.

It is a front external view of the refrigerator which concerns on embodiment of this invention. It is XX sectional drawing of FIG. 1 showing the structure in the refrigerator which concerns on embodiment of this invention. It is a front view showing the structure in the store | warehouse | chamber of the refrigerator which concerns on embodiment of this invention. FIG. 3 is an enlarged explanatory view of a main part of FIG. 2. FIG. 4 is an enlarged explanatory diagram of main parts of FIG. 3. It is a perspective view of the cooler concerning the embodiment of the present invention. It is a flowchart which shows the abnormality detection procedure of a pipe heater circuit. It is the operating state of a compressor and a pipe heater, and the temperature transition of a cooler temperature sensor. It is a flowchart at the time of reducing the detection frequency of abnormality detection of a pipe heater circuit.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, the refrigerator which concerns on embodiment of this invention is demonstrated based on FIGS. 1-5. FIG. 1 is a front external view of a refrigerator according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line XX of FIG. 1 showing the configuration of the refrigerator according to the embodiment of the present invention. FIG. 3 is a front view illustrating a configuration inside the refrigerator of the refrigerator according to the embodiment of the present invention. FIG. 4 is an enlarged explanatory view of the main part of FIG. FIG. 5 is an enlarged explanatory view of a main part of FIG.

  In FIG. 1, the refrigerator main body 1 has a refrigerator compartment 2, a lower freezer compartment 5, and a vegetable compartment 6 arranged from above. Further, the ice making chamber 3 and the upper freezing chamber 5 are provided side by side between the refrigerator compartment 2 and the lower freezing chamber 5. As an example, the refrigerator compartment 2 and the vegetable compartment 6 are storage rooms in a refrigeration temperature zone of approximately 3 to 5 ° C., and the ice making chamber 3, the upper freezer compartment 4 and the lower freezer compartment 5 are in a freezing temperature zone of approximately −18 ° C. It is a storage room.

  The front opening of the refrigerator compartment 2 is provided with refrigerator doors 2a and 2b with double doors (also called French doors) divided into left and right. The ice making room 3, the upper freezing room 4, the lower freezing room 5, and the vegetable room 6 include a drawer type ice making room door 3a, an upper freezing room door 4a, a lower freezing room door 5a, and a vegetable room door 6a. Further, a packing (not shown) is provided on the surface of each door on the storage chamber side so as to follow the outer edge of each door. When each door is closed, the outside air enters the storage chamber, and the storage chamber. It has a structure that suppresses cold air leakage from the air.

  The refrigerator main body 1 has a door sensor (not shown) that detects the open / closed state of the door provided in each storage room, and a state in which each door is determined to be open for a predetermined time (for example, 1 minute). When it exceeds (continuation), a means for notifying the user with an alarm is provided. Further, a temperature setting device (not shown) for setting the temperature of the refrigerator compartment 2 and the temperature of the upper freezer compartment 4 and the lower freezer compartment 5 is provided.

  In FIG. 2, the outside of the refrigerator body 1 and the inside of the refrigerator are thermally insulated by a heat insulating box 10 formed by filling a foam heat insulating material (foamed polyurethane foam) as a heat insulating layer between the inner box 1b and the outer box 1a. It is divided into. A plurality of vacuum heat insulating materials 23 are mounted in the heat insulating box 10 together with the foam heat insulating material. Although the vacuum heat insulating material 23 is mounted on the back side of the heat insulating box 10 in FIG. 2, the heat insulating box 10 may be mounted on the side, top and bottom surfaces of the heat insulating box 10 or in the door.

  In the refrigerator main body 1, the refrigerator compartment 2, the upper freezer compartment 4, and the ice making chamber 3 (shown in FIGS. 1 and 2) are partitioned in an adiabatic manner by the upper heat insulating partition portion 33, and the lower refrigeration portion by the lower heat insulating partition portion 34. Chamber 5 and vegetable compartment 6 are partitioned insulatively. In addition, as shown in FIG. 2, a horizontal partition 35 is provided in the upper part of the lower freezer compartment 5. The horizontal partition 35 partitions the ice making chamber 3 and the upper freezing chamber 4 and the lower freezing chamber 5 in the vertical direction. A vertical partition 36 (shown in FIG. 1) is provided between the refrigerator compartment doors 2a and 2b, and this vertical partition 36 is magnetized by the refrigerator compartment doors 2a and 2b, the ice making compartment door 3a, and the upper freezer compartment door 4a. It becomes a surface.

  Since the ice making chamber 3, the upper freezing chamber 4 and the lower freezing chamber 5 are all freezing temperature zones, the horizontal partitioning portion 35 and the vertical partitioning portion 36 have at least the refrigerator main body 1 to receive the seal member of each door. It only needs to be on the front side (shown in FIG. 1). That is, gas may move between the ice making chamber 3, the upper freezing chamber 4, and the lower freezing chamber 5 that are in the freezing temperature zone, or it may be a case where there is no heat insulation section. On the other hand, in the case where the upper freezer compartment 4 is a temperature switching chamber, it is necessary to perform heat insulation, and therefore the horizontal partition 35 and the vertical partition 36 extend from the front side of the refrigerator body 1 to the rear wall.

  A plurality of door pockets 27 are provided on the storage room side of the refrigerator compartment doors 2a and 2b (shown in FIG. 2). The refrigerator compartment 2 is provided with a plurality of shelves 31. The shelf 31 divides the refrigerator compartment 2 into a plurality of storage spaces in the vertical direction.

  As shown in FIG. 2, the upper freezer compartment 4, the lower freezer compartment 5, and the vegetable compartment 6 move in the front-rear direction together with a door provided in front of each storage compartment. In addition, storage containers 3b, 4b, 5b, and 6b are provided in the upper freezer compartment 4, the lower freezer compartment 5, and the vegetable compartment 6, respectively. The ice making room door 3a, the upper freezing room door 4a, the lower freezing room door 5a, and the vegetable room door 6a are each put on a handle portion (not shown) and pulled out to the front side, whereby the storage containers 3b, 4b, 5b, 6b can be pulled out.

  2 and 3, the refrigerator main body 1 of the present embodiment includes a cooler 7 as a cooling means. The cooler 7 (as an example, a fin tube type heat exchanger) is stored in a cooler storage chamber 8 provided on the back surface of the lower freezing chamber 5. In addition, a blower 9 (a propeller fan as an example) is attached as a blowing means in the cooler storage chamber 8 and above the cooler 7. Air cooled by heat exchange with the cooler 7 (hereinafter, low-temperature air heat-exchanged by the cooler 7 is referred to as “cold air”) is sent by the blower 9 via the refrigerator compartment air duct 11 and the freezer compartment air duct 12. , The refrigerator compartment 2, the vegetable compartment 6, the upper freezer compartment 4, the lower freezer compartment 5, and the ice making room 3 are sent to the respective storage rooms. The air blown to each of the storage chambers 2, 3, 4, 5, 6 is sent to the first air flow control means (refrigeration chamber damper 18) for controlling the air flow to the refrigeration temperature zone chamber and to the refrigeration temperature zone chamber. It is controlled by second air flow control means (freezer compartment damper 32) for controlling the air volume.

  Incidentally, the air ducts to the refrigerator compartment 2, the ice making room 3, the upper freezer room 4, the lower freezer room 5, and the vegetable room 6 are shaped as shown by broken lines in FIG. Is provided on the back side. Specifically, when the refrigerator compartment damper 18 is in the open state and the freezer compartment damper 32 is in the closed state, the cold air is blown into the refrigerator compartment 2 from the outlets 2c provided in multiple stages via the refrigerator compartment air duct 11. .

  As shown in FIG. 3, the cold air that has cooled the refrigerator compartment 2 passes through the refrigerator compartment return duct 14 from the refrigerator compartment return port 2 d provided in the lower part of the refrigerator compartment 2, and the lower right rear side of the lower heat insulating partition 34. Is sent to the vegetable compartment 6 from the vegetable compartment outlet 6c provided in the vegetable compartment. In addition, as shown in FIG. 2, the return cold air from the vegetable compartment 6 passes through the vegetable compartment return duct 16 from the vegetable compartment return duct inlet 16 b provided in front of the lower part of the lower heat insulating partition 34, and then returns to the vegetable compartment return duct. It returns to the lower part of the cooler storage chamber 8 from the outlet 16a.

  As another configuration, the refrigeration chamber return duct 14 (shown in FIG. 3) may be returned to the lower right side when viewed from the front of the cooler storage chamber 8 without communicating with the vegetable chamber 6. As an example in this case, a vegetable room air duct (not shown) is arranged at the front projection position of the refrigerator compartment return duct 14, and the cold air heat-exchanged by the cooler 7 is transferred from the vegetable room outlet 6 c to the vegetable room 6. It will blow directly.

  Moreover, it is good also as a structure which selectively controls whether the cold air of the refrigerator compartment return duct 14 is sent to the vegetable room 6 or the cooler storage room 8. In this case, for example, a configuration in which air blowing control means (for example, an electric damper) is provided in a part of the refrigerating room return duct 14 and the communication state and the closed state on the vegetable room 6 side and the cooler storage room 8 side are switched is exemplified.

  As shown in FIG. 2, a partition member 13 that partitions each storage chamber and the cooler storage chamber 8 is provided in front of the cooler storage chamber 8. The partition member 13 has an ice making chamber outlet 3c, an upper freezer compartment outlet 4c, and a lower freezer compartment outlet 5c. When the freezer damper 32 is open, heat is exchanged by the cooler 7. Cold air is blown by the blower 9 to the ice making chamber 3 and the upper freezing chamber 4 from the blowout ports 3c and 4c through the ice making chamber blowing duct (not shown) and the freezing chamber blowing duct 12, respectively. Further, the air is blown from the outlet 5 c to the lower freezer compartment 5 through the freezer compartment air duct 12.

  Generally, cold air having a low temperature with respect to the ambient temperature forms a downward flow from the upper side to the lower side. Therefore, by supplying more cold air to the upper side of the storage chamber, the storage chamber can be favorably cooled by the action of the downward flow. In this embodiment, although the freezer compartment damper 32 is provided, it considers so that the ventilation from the air blower 9 can be smoothly sent to the ice making room 3 or the upper freezer compartment 4 by installing this in the upper part of the air blower 9. ing. If the ice making chamber 3, the upper freezing chamber 4, and the lower freezing chamber 5 are configured to communicate with each other, the cooling effect by the downflow can be enhanced.

  The partition member 13 is provided with a freezer return port 15 at a position in the lower part of the lower freezer compartment 5, and the cold air that has cooled the upper freezer chamber 4, the lower freezer chamber 5, and the ice making chamber 3 is supplied to the freezer return port. It flows into the cooler storage chamber 8 through 15. The freezer compartment return port 15 has a width dimension substantially equal to the width of the cooler 7.

  In FIG. 4, in the refrigerator main body 1, a blower 9 is provided above the cooler 7, and a freezer compartment damper 32 is provided above the blower 9. In addition, an upper freezer compartment outlet 4c and an ice making compartment outlet 3c (also shown in FIG. 3) are provided above the freezer damper 32 to send cold air to the upper freezer compartment 4 located in the upper stage of the storage compartment in the freezing temperature zone. ing. The upper freezer compartment outlet 4c has the largest opening area among the outlets of the freezer compartment.

  In FIG. 5, the cold air that has cooled the refrigerating chamber 2 is provided on the side of the cooler storage chamber 8 as indicated by an arrow, and passes through the refrigerating chamber return duct 14 that communicates the refrigerating chamber 2 and the vegetable chamber 6. It flows into the vegetable compartment 6 through the vegetable compartment outlet 6c shown in FIG. The return cold air from the vegetable compartment 6 flows in from the vegetable compartment return duct inlet 16b (shown in FIG. 2), and as shown in FIG. 4, the vegetable compartment return duct 16 provided in the lower heat insulating partition 34 is passed through. Then, it flows into the cooler storage chamber 8 from a vegetable room return outlet 17 a (shown in FIG. 5) provided in front of the lower portion of the cooler storage chamber 8 and having a width approximately equal to the width of the cooler 7.

  On the other hand, as shown in FIG. 4, the cool air that has cooled the refrigeration temperature zone chamber is provided in the lower part of the partition portion 38 of the cooler storage chamber 8 that partitions the cooler storage chamber 8 and the refrigeration temperature zone chamber. It flows into the cooler storage chamber 8 through the freezer return port 15 having a width dimension substantially equal to the width of the cooler. A radiant heater 20, which is a glass tube heater, is provided below the cooler storage chamber 8. An upper cover 20 a (shown in FIG. 4) is provided above the radiant heater 20 in order to prevent defrost water from dripping onto the radiant heater 20.

  The frost adhering to the wall of the cooler 7 and the surrounding cooler storage chamber 8 is melted at the time of the defrosting operation, and the defrost water generated at that time is the eaves 21 ( (Shown in FIG. 4). The defrost water that has flowed into the basket 21 reaches the evaporating dish 19 disposed in the machine room 39 via the drain pipe 25, and generates heat from the condenser (not shown) and the compressor 22 disposed in the machine room 39. Can be evaporated.

  Further, as shown in FIG. 5, when viewed from the front of the cooler 7, the upper left part is a cooler temperature sensor 30 attached to the cooler 7, the refrigerating room 2 has a refrigerating room temperature sensor 28 (shown in FIG. 4), The lower freezer compartment 5 is provided with a freezer compartment temperature sensor 29 (shown in FIG. 4). By these temperature sensors 28, 29, and 30, the temperature of the cooler 7 (hereinafter referred to as the cooler temperature), the temperature of the refrigerator compartment 2 (hereinafter referred to as the refrigerator compartment temperature), and the temperature of the lower freezer compartment 5 (hereinafter referred to as the freezer). (Referred to as room temperature). Furthermore, the refrigerator body 1 includes an outside air temperature sensor (not shown) that detects the temperature outside the refrigerator. The vegetable room 6 is also provided with a vegetable room temperature sensor 37 (shown in FIG. 2).

  As an example of the control means, a control board 26 (shown in FIG. 2) 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. The control board 26 is connected to the outside air temperature sensor, the cooler temperature sensor 30, the refrigerating room temperature sensor 28, the freezer room temperature sensor 29, and the vegetable room temperature sensor 37. Furthermore, the door 2a, 2b, 3a, 4a, 5a, 6a is connected to the door sensor that detects the open / closed state of each door, a temperature setter (not shown) provided on the inner wall of the refrigerator compartment 2, and the like.

  The control board 26 controls the ON / OFF of the compressor 22 that compresses the refrigerant by a program preinstalled in the ROM, and each actuator (not shown) that individually drives the refrigerator compartment damper 18 and the freezer compartment damper 32. Control, ON / OFF control and rotation speed control of the blower 9 that blows air that has passed through the cooler 7 to the storage chamber, and control of ON / OFF of the alarm that informs the door open state are performed.

  Next, based on FIG.6 and FIG.7, the structure of a cooler is demonstrated. FIG. 6 is a perspective view of the cooler according to the embodiment of the present invention. FIG. 7 is a cross-sectional view of a main part around the cooler of the refrigerator according to the embodiment of the present invention.

  In FIG. 6, the cooler 7 has a refrigerant pipe 40 in which a plurality of fins 7 a are inserted in a serpentine shape so as to have a plurality of stages in the vertical direction. The substantially U-shaped curved portions connecting the upper and lower stages located at both ends of the refrigerant pipe 40 are respectively supported by the side plates 7b and 7c, and the cooler 7 having a substantially rectangular outer shape is configured. Yes. An accumulator 40 a is attached to one end of the refrigerant pipe 40.

  The pipe heater 41 is disposed so as to be in contact with or close to the cooler 7, and as an example, is configured in a meandering manner so as to be positioned in a gap between the upper and lower fins 7a. Further, the substantially U-shaped curved portions that are located at both ends of the pipe heater 41 and connect the upper stage and the lower stage are respectively supported by the side plates 7b and 7c. As an example, the pipe heater 41 is formed by inserting a cord heater into an aluminum pipe. In the present embodiment, the frost attached to the cooler 7 is melted by the radiant heater 20 and the pipe heater 41 shown in FIG.

  In addition, when the radiant heater 20 continues to be in an energized state contrary to control due to an unintended circuit abnormality due to some cause, the temperature of the cooler 7 may rise to an overtemperature. In order to prevent this, a temperature fuse for preventing overcooling of the cooler is provided in the cooler 7 or in the vicinity of the cooler 7 (not shown).

Here, the protection from the circuit abnormality etc. of the radiant heater 20 is demonstrated.
The radiant heater 20 is provided in the lower part of the cooler storage chamber 8 as described above, and heats the cooler 7 from below by radiant heat. When the radiant heater 20 is continuously energized due to an unintended circuit failure or the like due to any cause, the thermal effect on the cooler 7 and the temperature fuse for preventing the cooler overtemperature increases, and the temperature for preventing the cooler overtemperature is increased. The fuse reaches the fusing temperature and the thermal fuse is blown. Therefore, it is possible to determine whether the circuit of the radiant heater 20 is normal or not by the thermal fuse for preventing the cooler overtemperature.

  However, since the pipe heater 41 is disposed so as to be in contact with or close to the cooler 7 and heats the cooler 7 by heat transfer, the thermal influence from the pipe heater 41 on the thermal fuse is different from that of the radiant heater 20. Even when the pipe heater 41 is continuously energized due to a circuit abnormality or the like, the temperature fuse may not reach the fusing temperature. Therefore, the pipe heater 41 needs to be provided with a failure detection function that does not depend on the temperature fuse.

<Description of operation>
Next, the abnormality detection function of the circuit of the pipe heater 41 will be described with reference to FIGS. FIG. 7 is a flowchart showing an abnormality detection procedure of the pipe heater circuit. FIG. 8 shows the operating state of the compressor and the pipe heater and the temperature transition of the cooler temperature sensor.

  After the defrosting operation is started during the operation of the refrigerator (step S120 in FIG. 7), the defrosting operation is continued until the cooler temperature sensor temperature becomes equal to or higher than the preset defrosting end temperature c ( FIG. 7 Step S121 No). When the cooler temperature sensor temperature is equal to or higher than the defrosting end temperature, the defrosting operation is ended (Yes in step S121 in FIG. 7).

  Next, the compressor 22 is turned on to cool the refrigerator storage chamber (step S123 in FIG. 7). In addition, before and after the timing when the compressor 22 is turned on, the blower 9 is also turned on, and the low-temperature air that has passed through the cooler 7 is blown into the storage chamber.

  Thereafter, after the refrigerator storage chamber is sufficiently cooled, the compressor 22 is turned off (step S125 in FIG. 7). The blower 9 is also turned off.

  This time point is the time point when the compressor 22 is turned on and off at least once after the defrosting operation is completed, and the abnormality (failure) detection control mode 1 (first control mode) is started from here (FIG. 7 and FIG. 7). Point A in FIG. 8).

  At the start of the abnormality (failure) detection control mode 1, the cooler temperature sensor temperature a1 is stored (step S126 in FIG. 7). At this time, the radiant heater 20, the pipe heater 41, the compressor 22 and the like are turned off.

  Thereafter, after a preset abnormality (failure) detection time t1 has elapsed (Yes in step S127 in FIG. 7), the current cooler temperature sensor temperature a2 is stored (step S128 in FIG. 7), and the above-described compressor is OFF. The absolute value of the difference from the cooler temperature sensor temperature a1 is calculated. When the calculation result is compared with a preset abnormality (failure) determination threshold value a, and the calculation result is larger than the abnormality (failure) determination threshold value a, that is, | a2-a1 |> a ( In FIG. 7, step S129, No), the temperature rise of the cooler 7 is large, so that the energization state to the pipe heater 41 is not released in spite of the control command for turning off the pipe heater 41. It is determined that it is in a state. In this case, an abnormality (failure) alarm display for notifying the user that an abnormality that cannot cancel the energized state in the pipe heater circuit is performed (step S137 in FIG. 7). The abnormal (failure) alarm display is not limited to visual notification means, but may be any known notification means that is a voice or the like and can be recognized by the user.

  If the value is not more than the abnormality (failure) determination threshold value a, that is, | a2-a1 | ≦ a (Yes in step S129 in FIG. 7), it is determined as normal and the process proceeds to the next step.

  This time is the time when the abnormality (failure) detection control mode 1 ends (point B in FIGS. 7 and 8).

  Further, after the abnormality (failure) detection control mode 1 ends, the abnormality (failure) detection control mode 2 (second control mode) is started (point C in FIGS. 7 and 8).

  At the start of the abnormality (failure) detection control mode 2, the cooler temperature sensor temperature b1 is stored (step S130 in FIG. 7), and the pipe heater 41 is turned on (step S131 in FIG. 7). At this time, the radiant heater 20, the compressor 22 and the like are turned off.

  Thereafter, after elapse of a preset failure detection time t2 (Yes in step S132 in FIG. 7), the current cooler temperature sensor temperature b2 is stored (step S134 in FIG. 7), and the above-described cooler temperature sensor temperature b1 is stored. Calculate the absolute value of the difference.

  The calculation result is compared with a preset abnormality (failure) determination threshold value b, and the calculation result is a value smaller than the abnormality (failure) determination threshold value b, that is, | b2-b1 | <b ( In step S135 of FIG. 7, the pipe heater 41 is not energized in spite of the control command for turning on the pipe heater 41. Therefore, it is determined that the temperature rise of the cooler 7 is small, and the pipe heater circuit is energized. In order to notify the user that an abnormality (failure) in the disconnection state that does not become an error has occurred, an abnormality (failure) alarm display is performed (step S137 in FIG. 7). The abnormal (failure) alarm display is not limited to visual notification means, but may be any known notification means that is a voice or the like and can be recognized by the user.

  If the value is greater than or equal to the abnormality (failure) determination threshold value b, that is, | b2-b1 | ≧ b (Yes in step S135 in FIG. 7), it is determined to be normal, and the process proceeds to the next step. This time is the time when the abnormality (failure) detection control mode 2 ends (point D in FIGS. 7 and 8).

After performing the abnormality (failure) determination in the above two abnormality (failure) detection control modes (first control mode and second control mode), the process returns to the normal cooling operation.
As described above, the abnormality (failure) detection of the pipe heater circuit is realized.

  Next, FIG. 9 shows a flowchart in a case where the detection frequency of abnormality (failure) detection of the pipe heater circuit is reduced. When the refrigerator is normally cooled (step S141 in FIG. 9), the defrosting operation is started (step S142 in FIG. 9), and when the defrosting operation is completed (step S143 in FIG. 9), it is stored in the ROM of the control board. 1 is added to the defrosting counter n indicating the number of defrosting times, and n = n + 1 is set (step S144 in FIG. 9). Here, the “cooling operation” refers to a state in which the compressor 22 is turned on and the blower 9 is turned on to perform control to blow low-temperature air into the storage chamber. “Defrosting operation” means that the compressor 7 is turned off, the blower 9 is turned off, and at least one of the radiant heater 20 and the pipe heater 41 is turned on, and the cooler 7 is defrosted. The state that is.

  Next, the calculated defrost counter n is compared with a preset abnormality (failure) detection execution threshold N, and the calculated defrost counter n is a value equal to or greater than the abnormality (failure) detection execution threshold N, That is, if n ≧ N (Yes in step S145 in FIG. 9), the process proceeds to the pipe heater circuit failure detection control mode.

  When the defrost counter n is smaller than the abnormality (failure) detection execution threshold N, that is, n <N (No in step S145 in FIG. 9), the mode is shifted to the failure detection control mode of the pipe heater circuit. Return to normal cooling operation.

  That is, the above-described abnormality (failure) detection control mode is entered for each abnormality (failure) detection execution threshold value N. In the abnormality (failure) detection control mode, since the pipe heater 41 is energized, power is consumed to detect the abnormality (failure). Therefore, it is possible to suppress power consumption by reducing the frequency of abnormality (failure) detection, and it is possible to suppress power consumption while performing abnormality (failure) detection.

  According to the above embodiment of the present invention, the following effects can be obtained.

  That is, a cooler, a radiant heater below the cooler, a pipe heater disposed in contact with or close to the cooler, a cooler temperature sensor that detects the temperature of the cooler, the radiant heater, and A control unit that controls energization of the pipe heater, and the control unit controls the pipe heater and the radiant heater to be in a non-energized state, and the cooler temperature sensor increases a predetermined temperature. When the temperature of the pipe heater circuit is detected, the cooler temperature sensor does not detect a predetermined temperature rise when the pipe heater circuit is controlled to be energized and the pipe heater is controlled to be energized. And a second control mode for determining that the pipe heater circuit is disconnected.

  Thereby, the precision which detects that the heater is controlled normally can be improved further.

  A compressor that compresses the refrigerant; and a blower that blows the air that has passed through the cooler to the storage chamber. The first control mode and the second control mode are provided in the pipe heater or the radiant heater. It is after the defrost operation which energizes and defrosts the said cooler, Comprising: It carries out after driving the said compressor and the said air blower.

  Thereby, the detection accuracy of the temperature rise by the cooler temperature sensor is further improved, and the accuracy of detecting that the heater is normally controlled can be further improved.

  The first control mode and the second control mode are performed every time a defrosting operation in which the pipe heater or the radiant heater is energized to defrost the cooler is performed a predetermined number of times.

  Accordingly, it is possible to suppress power consumption by reducing the frequency of abnormality (failure) detection, and it is possible to suppress power consumption while performing abnormality (failure) detection.

  The embodiment of the present invention has been described above. For example, the start timing of the abnormality (failure) detection control mode 1 and the start timing of the abnormality (failure) detection control mode 2 are synchronized, and the cooler temperature sensor temperature a2 = b1. It is good.

  In the present embodiment, the pipe heater 41 has been described. However, when the temperature fuse is not provided, the failure detection control mode may also be used for the radiant heater 20.

DESCRIPTION OF SYMBOLS 7 ... Cooler, 8 ... Cooler storage chamber, 9 ... Blower, 20 ... Radiant heater, 22 ... Compressor, 41 ... Pipe heater

Claims (3)

A cooler, a radiant heater below the cooler, a pipe heater disposed in contact with or in proximity to the cooler, a cooler temperature sensor for detecting the temperature of the cooler, the radiant heater and the pipe A controller for controlling energization of the heater,
The control unit determines that the pipe heater circuit is in error energization when the cooler temperature sensor detects a predetermined temperature rise when the pipe heater and the radiant heater are controlled in a non-energized state. A first control mode to
A second control mode for determining that the pipe heater circuit is disconnected if the cooler temperature sensor does not detect a predetermined temperature rise when the pipe heater is controlled to be energized. A refrigerator characterized by that. A compressor that compresses the refrigerant, and a blower that blows air that has passed through the cooler to the storage chamber,
The first control mode and the second control mode are performed after the defrosting operation in which the pipe heater or the radiant heater is energized to defrost the cooler and after the compressor and the blower are driven. The refrigerator according to claim 1, wherein:   The first control mode and the second control mode are performed each time a defrosting operation for defrosting the cooler by energizing the pipe heater or the radiant heater is performed a predetermined number of times. Or the refrigerator of 2.