JPH0634253A - Refrigerator - Google Patents

Abstract

PURPOSE:To promote an automatic defreezing of frozen items when they are stored in the storing box by a method wherein a defreezing promoting mechanism is operated in the case that a temperature decreasing degree within the storing box detected by a temperature sensing means is higher than that of normal cooling operation. CONSTITUTION:As a temperature within a refrigerator is less than a set lower limit temperature, electrical energization for a compressor motor 52a and an air-cooled fan 53 is stopped. However, if temperature of the stored frozen items is sufficiently low, the temperature within the refrigerator is further decreased. Then, as the temperature within the refrigerator is further decreased than a fan starting temperature, a temperature sensor Th3 is electrically energized, so that an exciting coil of a relay R7 is electrically energized and a relay R8 in a self-holding circuit 88 is self held in its ON state. Then, a make contact point R8-2 connected in series with the inter- refrigerator fans 30a and 30b is electrically conducted and then the inter-refrigerator fans 30a and 30b are electrically energized by electrical power supplying passages PW1 and PW2 through this make contact point R8-2. Then, the fan 32 is rotated by fan motors 31 in the inter-refrigerator fans 30a and 30b to circulate air within the chamber RM1 and to promote defreezing operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator for cooling the inside of a storage box, and more particularly to a refrigerator having a thawing promotion mechanism for accelerating the thawing in the storage box.

[0002]

2. Description of the Related Art Conventionally, as this type of refrigerator, one disclosed in Japanese Patent Laid-Open No. 2-157576 is known. What is disclosed in the publication is to dispose a storage box in the heat insulation box, and to install an evaporator of a cooling mechanism and a cooling fan for blowing air cooled by the evaporator between the heat insulation box and the storage box. The storage box is provided with a convection fan that blows downward cooling air upward to cause convection.

In this structure, when the cooling fan blows the air cooled by the evaporator to the outer circumference of the storage box,
The air in the storage box is cooled through the wall material of the storage box,
The perishables stored in the storage box are indirectly cooled. In addition, the convection fan blows the air inside the storage room upwards to generate an air flow inside the storage room.

[0004]

By the way, a refrigerator that indirectly cools the inside of the storage box is generally characterized in that the inside of the storage box is kept at high humidity. It was found that a large frozen product can be thawed in a short time by blowing air with a predetermined amount or more.

However, in the conventional refrigerator,
It merely circulates an air flow that allows convection of the air flow in the refrigerator, and even if a large frozen product is stored, it is not possible to promote thawing as it is. on the other hand,
If you have a mechanism to facilitate thawing when needed,
It is necessary to store the frozen mass in the storage box and activate the mechanism, but if the operator forgets to instruct the operation, thawing cannot be promoted. Then, even though I think that the decompression should be completed, the situation that the decompression is not completed occurs.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a refrigerator that can be operated to automatically promote thawing when a frozen product is stored in a storage box. .

[0007]

In order to achieve the above object, the invention according to claim 1 is a refrigerator for cooling the inside of a storage box, and a defrosting promoting mechanism for promoting defrosting in the storage box, and the storage box. And a defrosting control means for activating the defrosting promoting mechanism when the temperature inside the storage box detected by the temperature sensing means is lower than the normal cooling. It has a different structure.

The invention according to claim 2 is based on claim 1.
In the refrigerator according to, the thawing control means, when the temperature in the storage box detected by the temperature detection means becomes lower than a predetermined temperature, the way the temperature in the storage box falls is lower than that in normal cooling. It is configured to judge that it is large. Further, the invention according to claim 3 is the refrigerator according to claim 2, wherein the defrosting control means sets the temperature inside the storage box detected by the temperature detection means to a predetermined holding temperature range or less in normal times. When the temperature is lower than the temperature, it is determined that the temperature in the storage box is lower than the normal cooling.

The invention according to claim 4 is the same as that of claim 2
In the refrigerator according to claim 3, the defrosting control means causes the temperature inside the storage box to decrease only when the temperature inside the storage box detected by the temperature detection means becomes lower than the predetermined temperature. It is configured to judge that it is larger than the normal cooling. Further, the invention according to claim 5 is the refrigerator according to claim 1, wherein the thaw control means detects the degree of change in the temperature in the storage box detected by the temperature detection means. When the degree of change shows a sudden decrease below a predetermined degree of change, it is determined that the way the temperature in the storage box falls is larger than the normal cooling.

[0010]

In the invention according to claim 1 configured as described above, when the frozen product is stored in the storage box, the internal temperature of the refrigerator decreases, so that the thawing control means detects the storage detected by the temperature detecting means. The thawing promotion mechanism is operated by judging that the way the temperature inside the box decreases is larger than the temperature decrease during normal cooling. That is, it is detected that the frozen mass lowers the ambient temperature, and the defrosting promoting mechanism is activated.

Further, in the invention according to claim 2 configured as described above, when the temperature in the storage box detected by the temperature detecting means becomes lower than a predetermined temperature, the thawing control means is arranged in the storage box. It is judged that the temperature decrease is larger than the normal cooling, and the thawing promotion mechanism is operated assuming that the frozen product is contained. That is, when it is detected that the frozen mass has lowered the ambient temperature and becomes lower than the predetermined temperature,
Activate the thawing mechanism.

Further, in the invention according to claim 3 configured as described above, when the temperature in the storage box detected by the temperature detecting means becomes lower than a predetermined temperature which is equal to or lower than the holding temperature range in normal times. The thawing control means determines that the temperature inside the storage box is lower than the normal cooling, and operates the thawing promotion mechanism assuming that the frozen product is stored.

That is, when it is detected that the frozen mass lowers the ambient temperature and becomes lower than the holding temperature range which should not be lowered originally, the thawing promotion mechanism is activated. Further, in the invention according to claim 4 configured as described above, the thawing control means sets the temperature in the storage box only when the temperature in the storage box detected by the temperature detection means becomes lower than the predetermined temperature. It is judged that the cooling rate is larger than the normal cooling, and the thawing promotion mechanism is operated assuming that the frozen product is stored.

That is, the thawing promotion mechanism is not activated except when the frozen mass is cooled to a temperature lower than a predetermined temperature by lowering the ambient temperature. Further, in the invention according to claim 5 configured as described above, the degree of change in the temperature inside the storage box detected by the temperature detecting means is detected, and the detected degree of change is greater than the predetermined degree of change. When it also shows a sharp drop, the thawing control means determines that the temperature in the storage box is lower than the normal cooling, and operates the thawing promotion mechanism assuming that the frozen product is stored.

That is, when the frozen mass lowers the ambient temperature and the temperature drops more rapidly than in normal times, the thawing promotion mechanism is activated.

[0016]

As described above, according to the present invention, the thawing promotion mechanism is operated when the frozen product is stored in the storage box based on the temperature change. Therefore, the thawing promotion mechanism is forgotten to be operated. It is possible to provide a refrigerator with no problem.

Further, according to the invention of claim 3, since the thawing promoting mechanism is operated after the temperature which should not be lowered originally, erroneous detection is small, and according to the invention of claim 4, it is to some extent. If the temperature is not low, thawing will not be promoted, preventing the situation of thawing too much. Further, according to the invention of claim 5, the thawing promotion mechanism is activated when the temperature drops suddenly so far as to be unthinkable in terms of the cooling capacity, so that there is little false detection.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. <First Embodiment> FIG. 1 is a front view of a refrigerator according to an embodiment of the present invention, FIG. 2 is a partially cutaway front view, and FIG. 3 is a partially cutaway top view. In the figure, the refrigerator main body includes a heat insulating box 10 and a storage box 20, and the heat insulating box 10 has a heat insulating material 13 such as urethane foam between an inner wall of an outer box 11 and an outer wall of an inner box 12.
And a pair of left and right openings 14 are formed on the front surface thereof.
a and 14b are formed and the openings 14a and 14 are formed.
Insulating doors 15a and 15b for opening and closing b are attached by hinges so as to be opened and closed.

The storage box 20 is formed of a metal plate material such as stainless steel, which is a heat conducting member, in the form of a housing having an opening 21 on one surface thereof.
Both of the openings 14a and 14b are aligned as desired, and are fixedly supported on the outer peripheral edge of the inner surface of the front wall of the heat insulating box 10. At this time, the left and right side walls 22, 23, the upper wall 24, the bottom wall 25, and the rear wall 26 of the storage box 20 are held at a predetermined distance from the inner wall of the inner box 12 in the heat insulating box 10, and the gap is maintained by the air flow. A circulation passage W is formed.

In the storage box 20, a partition wall 27 made of a metal plate made of stainless steel, which is a heat conducting member, is fixed to the upper wall 24 and the bottom wall 25 of the storage box 20 at the upper side and the lower side, respectively. The inside is divided into a room RM1 on the right side in the figure and a room RM2 on the left side in the figure. The partition wall 27 and the storage box 20 do not have to be hermetically sealed. Further, in this embodiment, the partition wall 27 is formed of a flat plate, but it may be formed of a plate material having a large surface area such as a corrugated plate to improve the heat exchange efficiency.

Two internal fans (defrosting promoting mechanism) 30
Each of a and 30b is constructed by fixing a fan 32 to the rotation axis of a fan motor 31, and has both ends in a chamber RM1 with respect to a support column 33 fixed to the upper wall 24 and the bottom wall 25 of the storage box 20. It is installed. In addition, the internal fan 30
A cover 40 is fixedly attached to the front wall of a and 30b to the upper wall 24 and the bottom wall 25 of the storage box 20 at the upper and lower sides thereof. The cover 40 has a position corresponding to the fan 32 and its position. Vent holes 41 are formed on both sides.

The left side wall 2 of the storage box 20 in the heat insulating box 10
The evaporator 51 of the cooling mechanism 50 is fixed to the wall portion facing 2 with its air flow path oriented vertically, and between the evaporator 51 and the left side wall 22 of the storage box 20, there is air above. The flow hole 61 is formed, and the shielding plate 60 having the air blower fan 62 arranged in the air flow hole 61 is fixed by its upper piece so as to hang from the upper wall of the inner box 12 of the heat insulating box 10. A sufficient gap is formed between the lower side of the shielding plate 60 and the lower wall of the inner box 12, and an air cooling flow passage communicating from the gap to the upper air circulation hole 61 via the air flow passage of the evaporator 51. Is formed.

As shown in FIG. 4, the cooling mechanism 50 includes a compressor 52 for compressing a refrigerant, a condenser 54 for condensing the compressed compressed refrigerant under the action of air cooling by an air cooling fan 53, and a condensing condenser. A dryer 55 that dehumidifies the refrigerant, a capillary tube 56 that converts the dehumidified condensed refrigerant into a low-temperature low-pressure refrigerant, and an evaporator that cools by the heat of vaporization of the low-temperature low-pressure refrigerant and supplies the vaporized refrigerant to the compressor 52. 51 and is housed in an auxiliary box 10a formed on the left side of the heat insulating box 10 except for the evaporator 51. In the figure, a hot gas valve 57 for supplying the high-temperature compressed refrigerant compressed by the compressor 52 to the evaporator 51 at the time of defrosting is provided with an output side of the compressor 52 and the evaporator 5.
It is interposed in a pipe line connecting the input side of No. 1.

The compressor 52 is the compressor motor 5
2a and a compression mechanism 52b that is driven by being connected to the rotation axis of the compressor motor 52a,
The drive of the compressor motor 52a is controlled by the temperature control sequence circuit 71a in the electric control circuit 70 as shown in FIG. The electric control circuit 70 is connected to a commercial AC power supply, and a main power switch 72 for opening and closing the commercial AC power supply and the internal power supply paths PW1 and PW2,
Consists of a blower fan 62 connected to the power supply paths PW1 and PW2, the temperature control sequence circuit 71a for controlling the temperature inside the chambers RM1 and RM2, and an internal fan control sequence circuit (defrosting control means) 71b. Has been done.

Here, the temperature control sequence circuit 71a
Is a temperature sensor Th1 and a relay R that conduct when the internal temperature T1 in the chamber RM1 becomes equal to or higher than a set upper limit temperature TH.
A series circuit S1 in which one exciting coil is connected in series; a series circuit S2 in which the temperature sensor Th2, which conducts when the internal temperature T1 becomes equal to or lower than the set lower limit temperature TL, and the exciting coil of the relay R3 are connected in series; Forced release circuit R4-
Make-up contacts R2-2 of the relay R2 and the relays S3 and S4 of the exciting coils in the relays R2 and R4 including R3 and R2-3, and a parallel circuit in which the compressor motor 52a and the air cooling fan 53 are connected in parallel. Series circuit S5 in which break contact R4-2 of R4 is connected in series
And are connected to the power supply paths PW1 and PW2.

In addition, the internal fan control sequence circuit 7
1b is a temperature sensor (temperature detecting means) Th3 and a relay R7 which are conducted when the inside temperature T1 in the room RM1 becomes equal to or lower than the fan starting temperature TS lower than the set lower limit temperature TL.
Series circuit S6 in which the excitation coils of are connected in series, and the fan stop temperature whose internal temperature T1 is higher than this fan starting temperature TS
A series circuit S7 in which a temperature sensor Th4 that conducts when TE (TE1, TE2, TE3) or more becomes conductive, and an exciting coil of a relay R9 are connected in series, and a forced release circuit R10-
3, the relay R7 including the relays R3 and R8-3, and the self-holding circuits S8 and S9 of the exciting coils in the relay R10 and the parallel circuit in which the internal fans 30a and 30b are connected in parallel.
Series circuit S1 in which eight make contacts R8-2 are connected in series
0 is connected to the power supply paths PW1 and PW2.

The temperature sensors Th1 to Th4 are mounted above the chamber RM1, respectively, and the fan stop temperature TE is set to the same temperature TE1 as the set lower limit temperature TL. Next, the operation of this embodiment having the above configuration will be described. When the main power switch 72 is turned on after the refrigerator is installed, the temperature T1 in the refrigerator is equal to or higher than the set upper limit temperature TH, so that the temperature sensor Th1 conducts and energizes the exciting coil of the relay R1. Then, the make contacts R1-1 and R1-2 in the self-holding circuit S3 of the relay R2 are turned on, and the exciting coil of the relay R2 is energized, so that the make contact R2-1 is turned on and the relay R2 is held in the on state. Excuse me.

When the relay R2 is turned on, the make contact R2
-2 becomes conductive, the compressor motor 52a and the air-cooling fan 53 are energized via the break contact R4-2 of the relay R4, and the cooling mechanism 50 is started. On the other hand, at the same time, the blower fan 62 also starts blowing air, sucking air from the gap between the lower side of the shielding plate 60 and the lower wall of the inner box 12 through the air flow path of the evaporator 51, and sucking the air. From the air circulation hole 61 to the air flow circulation passage W formed around the storage box 20. Therefore, the cooling mechanism 50
When the engine is started, the air sucked by the blower fan 62 is heat-exchanged when passing through the air flow path of the evaporator 51, and the cooled air is formed from the air circulation hole 61 to the air circulation passage formed around the storage box 20. It is blown to W.

Since the storage box 20 is formed of a heat conducting member, when the cooled air is blown to the outer periphery of each wall 22.
Heat exchange is carried out at ~ 26, and the temperature inside the chamber in the chambers RM1, RM2 gradually decreases. Then, even if the internal temperature T1 is lower than the set upper limit temperature TH and the temperature sensor Th1 is turned off, the relay R2 is kept in the on state and self-held, so that the cooling mechanism 50 continues to operate.

However, when the internal temperature T1 becomes lower than the set lower limit temperature TL, the temperature sensor Th2 is turned on and the relay R3 is turned on.
Energize the excitation coil of. Then, similarly to the case of the self-holding circuit S3 described above, the relay R4 is turned on, the break contact R4-3 constituting the forced release circuit of the relay R2 is turned off, and the self-holding state of the relay R2 ends. Also, as in the case of the relay R2, the relay R4
Since the ON state of the break contact is self-maintained, the break contact R4-
2 is turned off, the make contact R2-2 is also turned off. Therefore, the compressor motor 52a and the air cooling fan 5
The power supply to 3 is stopped, and the cooling mechanism 50 is also deactivated.

Thereafter, the temperature control sequence circuit 71 is used.
a is a set upper limit temperature T1 as shown in FIG.
Control to maintain within the range of TH and lower limit temperature TL. By the way, the set upper limit temperature TH and the set lower limit temperature TL in the refrigerator are adjusted within a range of several degrees with reference to about 0 degrees Celsius. Now, it is assumed that the room RM2 is used as a normal refrigerator and the room RM1 is used as a thawing room exclusively for thawing.

Initially, the internal temperature T1 is held between the set upper limit temperature TH and the set lower limit temperature TL, and the temperature sensor Th
3 is non-conductive and the temperature sensor Th4 is conductive. Therefore, if the temperature sensor Th3 is non-conducting, the exciting coil of the relay R7 is not energized.
7-1 and R7-2 become non-conductive, and the exciting coil of the relay R8 is not energized. Then, the internal fan 30
The make contact point R8-2 connected in series with a and 30b becomes non-conductive, and the inside fans 30a and 30b are stopped.

If the relay R8 is in the self-holding state of the ON state, the internal fans 30a and 30b are energized,
Since the temperature sensor Th4 is conducting, the forced release circuit R1
The relay R8 cancels the self-holding state by the action of 0-3. Therefore, initially, the internal fan 30a,
30b is always stopped. FIG. 7 shows the temperature (T
f) and the temperature (T1) in the room RM1 are shown. Now, when the frozen mass frozen at about -30 degrees Celsius is housed in the room RM1, the air in the refrigerator is The temperature T1 in the refrigerator sharply drops as shown in FIG.

When the internal temperature T1 becomes lower than the set lower limit temperature TL, the energization of the compressor motor 52a and the air cooling fan 53 is stopped as described above. However, if the temperature of the frozen mass is sufficiently low, the internal temperature T1 becomes It further decreases. When the internal temperature T1 becomes lower than the fan starting temperature TS, the temperature sensor T in the internal fan control sequence circuit 71b.
Since h3 is conductive, the exciting coil of the relay R7 is energized, and the relay R8 in the self-holding circuit S8 is self-held in the ON state. Note that here, the fan starting temperature TS
Is below the set lower limit temperature TL. During the cooling by the cooling mechanism 50, the inside temperature T1 cannot be lower than the set lower limit temperature TL, so the inside temperature T1 becomes lower than the fan starting temperature TS equal to or lower than the set lower limit temperature TL when the frozen mass is stored. It should be in a state. Therefore, erroneous detection can be prevented by setting the fan starting temperature TS under such conditions.

When the relay R8 is turned on,
Make contacts R8-2 connected in series to the internal fans 30a, 30b are conducted, and the internal fans 30a, 30 are connected to the internal power supply paths PW1, PW2 via the make contacts R8-2.
Power is supplied to b. Then, the fan 32 is rotated by the fan motor 31 in the internal fans 30a and 30b, and
Circulate the air inside RM1. That is, the internal fan 3
0a and 30b are arranged in the central portion of the storage box 20 by sucking air in the chamber RM1 through the front and rear ventilation holes 41 in the storage box 20 among the ventilation holes 41 provided in the cover 40. Air is blown from the ventilation hole 41 provided in front of the fan 32.

By starting the operation of the internal fans 30a and 30b, fresh air is constantly blown to the surface of the frozen mass to raise the surface temperature of the frozen mass and promote the thawing. At this time, since the air to be blown is kept at a high humidity, the frozen mass can be thawed at an early stage without causing deterioration without being excessively dried. In this way, when the frozen mass is stored in the chamber RM1, the internal temperature T1 becomes lower than the fan starting temperature TS, and the internal fans 30a and 30b automatically operate even if the user does not instruct special operation. To thaw the frozen mass efficiently and early.

On the other hand, the air that has raised the surface temperature of the frozen lump is, on the contrary, cooled by the frozen lump and the internal fan 30
By circulating the inside of the chamber RM1 by the functions of a and 30b, the temperature inside the chamber RM1 becomes uniform. When the air cooled by the frozen mass in the chamber RM1 is sucked into the space formed between the cover 40 and the partition wall 27 through the ventilation hole 41 formed in the cover 40 and exhausted through the other ventilation hole 41. Flow along the surface of the partition wall 27. As described above, since the partition wall 27 is manufactured by the heat conducting member, when the cooled air flows along the surface of the partition wall 27, the chamber RM1.
The cold heat inside is transferred to the room RM2 through the partition wall 27,
Cool the air in chamber RM2.

When the temperature of the frozen mass is extremely low, the air on the surface of the frozen mass is cooled to near the same temperature, but the air inside the chamber RM1 is forcibly circulated by the functions of the internal fans 30a and 30b. The internal temperature T1 is sufficiently higher than the temperature of the frozen mass and lower than the set lower limit temperature TL. On the other hand, the cold heat in the room RM1 is transferred to the room RM via the partition 27.
Although it is transmitted to the inside of the chamber 2 to cool the chamber RM2, it is not cooled by the air having an extremely low temperature cooled on the surface of the frozen mass as described above, and the temperature is raised to some extent by being circulated in the chamber RM1. It will be cooled with air. Therefore, the room RM
The temperature inside 2 does not drop sharply like the temperature inside room RM1,
It is cooled within the range between the set upper limit temperature TH and the set lower limit temperature TL.

Surface temperature Tf of frozen mass as thawing proceeds
And the temperature T1 in the chamber RM1 becomes smaller, and when the temperature T1 in the chamber approaches the set lower limit temperature TL, the thawing is almost completed and the surface temperature Tf of the frozen mass approaches the set lower limit temperature TL. Become. When the internal temperature T1 exceeds the fan stop temperature TE1 set equal to the set lower limit temperature TL, the temperature sensor T
Since h4 conducts to energize the exciting coil of the relay R9, the make contacts R9-1 and R9-2 are rendered conductive to make the relay R10 conductive, and the self-holding circuit S9 makes the relay R10 self-hold in the ON state. The break contact R10-3 of the relay R10 constitutes a forced release circuit in the self-holding circuit S8 of the relay R8, and the break contact R10-3 is provided by energizing the relay R10.
When is turned off, the power supply to the relay R8 is stopped. Therefore, the make contact point R8-2 connected in series with the in-compartment fans 30a and 30b becomes non-conducting, and the in-compartment fan 30 is made.
Stop a and 30b.

When the internal fans 30a and 30b are stopped, the rise of the surface temperature Tf in the frozen mass slows down, and
The internal temperature T1 in the RM1 continues to rise gradually. When the inside temperature T1 exceeds the set upper limit temperature TH, the cooling mechanism 50 is started as described above, and thereafter, the inside temperature T1 of the chamber RM1 is maintained between the set upper limit temperature TH and the set lower limit temperature TL. It becomes a normal refrigerator to store the frozen mass that has been thawed.

In the first embodiment, the internal fans 30a and 30b used to accelerate the thawing start operating at the fan starting temperature TS slightly lower than the set lower limit temperature TL, and the set lower limit temperature. Although the operation has ended at the fan stop temperature TE1 set to be the same as TL, the internal fan 30
The fan stop temperature for stopping a and 30b may be set to another temperature.

For example, the set lower limit temperature TL and the set upper limit temperature TH
Between the fan stop temperature TE2 and the set upper limit temperature TH
The same fan stop temperature TE3 can be set.
When set in this way, as shown in FIG. 7, the period during which the internal fans 30a and 30b are operating becomes long, and it is possible to even thaw even into the inside of a large frozen mass whose temperature is unlikely to rise. .

In a refrigerator equipped with an indicator for displaying the temperature inside the refrigerator, an indicator that can blink when a predetermined voltage is applied is used, and this signal terminal is arranged in parallel with the inside fans 30a and 30b. It may be configured to be connected. With this configuration, the internal fans 30a and 30b
The indicator blinks when defrosting when is activated. When the temperature display is flushing, it is easy for the user to see it even if he / she does not have any intention to read the temperature, and the user can very easily determine that the thawing is being performed. Further, when the temperature display becomes normal, the user can visually recognize the normal display and recognize that the thawing is completed. In this way, the display blinks when the temperature reaches the predetermined temperature range, so that it is possible to know that the temperature inside the refrigerator is changing or the container is being thawed without reading the temperature display.

In the first embodiment, the internal fans 30a and 30b are controlled by the wire logic sequence circuit 71b. However, the internal temperature T in the chamber RM1 is controlled.
A temperature sensor that detects 1; and a control unit that makes a predetermined determination with a microcomputer based on the detection result of the temperature sensor,
According to the judgment of the control unit, the internal fans 30a, 30b.
It is also possible to dispose a relay for controlling the energization of the compartments and operate and stop the internal fans 30a and 30b by software control.

That is, the control unit inputs the internal temperature T1 corresponding to the signal output from the temperature sensor at predetermined time intervals,
The inside temperature T1 is compared with a predetermined fan starting temperature TS, and when the inside temperature T1 is smaller, the relay is controlled to energize the inside fans 30a and 30b. On the other hand, after energization, it is determined whether the internal compartment temperature T1 is higher than the fan stop temperature TE, and when the internal compartment temperature T1 is higher, the relay is controlled to energize the internal compartment fans 30a, 30b. Stop.

By performing such control, the internal fans 30a and 30b can be operated and stopped in the same manner as in the above-mentioned wire logic. Further, in the sequence circuit 71b of the wire logic, the judgment when the frozen mass is accommodated is made by comparing the inside temperature T1 with the fan starting temperature TS, but the inside temperature T1 is determined by the software control. It is also possible to make a determination based on the speed at which it decreases.

FIG. 8 is a flow chart corresponding to a subroutine program for making such a judgment. This subroutine for determining the start start condition is executed at regular time intervals from the main routine that performs other processing by interrupt processing or the like, and the microcomputer of the control unit causes the temperature inside the refrigerator T1 (T1n) detected by the temperature sensor in step 100 to be , N represent the sampling timing. ) Is input and the lowering temperature (T1n-T1 (n-
1)) is measured. Then, in step 110, it is judged whether or not this temperature drop (T1n-T1 (n-1)) is larger than a predetermined temperature drop threshold value TTH. To finish.

In the cooling performed by the cooling mechanism 50 which is normally performed, there is a limit to the rate at which the inside temperatures T1 and T2 in the chambers RM1 and RM2 decrease, and the temperatures do not decrease very rapidly. However, if a frozen mass with a large specific heat is
The internal temperature T1 in the RM1 sharply drops. Therefore, when the lowered temperature (T1n-T1 (n-1)) is larger than the temperature lowering threshold value TTH, it can be determined that the frozen mass is accommodated in the chamber RM1, and the microcomputer proceeds to step 120. The internal fans 30a and 30b are started.

In this case, the rate of decrease of the internal temperature T1 is calculated one by one, but if the temperature decrease is abrupt, the operating time of the compressor motor 52a will be shortened.
The operating time of the compressor motor 52a is measured, and this operating time is compared with the past average operating time. If the operating time is shorter than the specified time, the room RM
It is only necessary to determine that the frozen mass is accommodated in 1 and start the internal fans 30a and 30b.

In the above-described embodiment, the internal fans 30a and 30b operate during thawing to blow an air volume suitable for thawing. However, during refrigeration, a small amount of air is blown in order to make the temperature in the chamber RM1 uniform. May be blown. In this case, the rotation speed of the fan motor 31 may be decreased during refrigeration, the fan motor 31 may be operated intermittently, or the number of internal fans 30a and 30b to be operated may be reduced.

Further, the internal fans 30a, 30 are provided in the room RM1.
b is provided, but the internal fans 30a, 3 are provided in the room RM2.
0b may be provided to serve as a thawing chamber. In-house fan 30
Two a and 30b are arranged above and below, but it is also possible to arrange only one below and blow air upward. Further, the blowing direction may be directed to the partition wall so as to promote heat exchange by the partition wall.

On the other hand, in the above-mentioned embodiment, the inside of the storage box is divided into two, but the number of divisions is arbitrary such as arranging the defrosting box in the center and dividing into three. Further, the division direction is arbitrary, such as division in the vertical direction instead of division into the right and left. Other control methods such as temperature control and defrost control are not limited to those in the above embodiment.

<Second Embodiment> FIG. 9 is a partially cutaway front view of a refrigerator according to an embodiment of the present invention, and FIG. 10 is a partially cutaway top view. In the second embodiment, unlike the first embodiment, the internal fans 30a and 30b are provided in the room RM2.
Is provided. In the figure, the refrigerator body is a heat insulating box 10.
The heat insulating box 10 is configured by filling a heat insulating material 13 such as urethane foam between the inner wall of the outer box 11 and the outer wall of the inner box 12, and the front surface of the heat insulating box 10 has a pair of left and right sides. The openings 14a and 14b are formed and the opening 14 is formed.
Adiabatic doors 15a and 15 for opening and closing a and 14b
b is attached by a hinge so that it can be opened and closed. A seal material 15a for insulating the outside air is provided between the heat insulating doors 15a and 15b and the peripheral edges of the openings 14a and 14b.
1, 15b1 are provided.

The storage box 20 is formed of a metal plate material such as stainless steel, which is a good heat conducting member, into a housing having an opening 21 on one surface thereof.
Both of the openings 14a and 14b are aligned as desired, and are fixedly supported on the outer peripheral edge of the inner surface of the front wall of the heat insulating box 10. At this time, the left and right side walls 22, 23, the upper wall 24, the bottom wall 25, and the rear wall 26 of the storage box 20 are held at a predetermined distance from the inner wall of the inner box 12 in the heat insulating box 10, and the gap is maintained by the air flow. A circulation passage W is formed.

In the storage box 20, a partition wall 27 made of a stainless metal plate material which is a heat conducting member is fixed to the upper wall 24 and the bottom wall 25 of the storage box 20 at the upper side and the lower side, respectively. Inside the room RM1 on the right side of the figure and room RM2 on the left side of the figure
It is divided into. A seal material (not shown) is provided around the partition wall 27, and the chambers RM1 and RM2 are airtightly separated from each other.

The two in-compartment fans 30a and 30b are constructed by fixing the fan 32 to the rotation axis of the fan motor 31, and are mounted on the left wall 22 of the storage box 20 in the chamber RM2. In addition, the internal fans 30a, 30
A cover 40 for forming an air flow path is attached to the front surface of b. The cover 40 has an exhaust port 41 formed in a portion facing the fan 32 and an intake port 42 formed in a lower portion. ing. That is, the upper side end of the cover 40 contacts the upper wall 24, the left side end bent to have an L-shaped cross section contacts the left side wall 22 of the storage box, and the right side end of the cover 40 rear wall. 26, the lower side is the left side wall 2
2 and the suction port 42 is formed with a predetermined gap therebetween.

A flat plate-like condensed water catching plate 28 shown in FIGS. 11 and 12 is attached to the upper wall 24 on the front side of the internal fans 30a and 30b. The dew condensation water catching plate 28 is integrally formed by holding a thin plate 28a having a large number of through holes and a base plate 28b having no holes at a minute distance from each other, and is pressed by a press. Projection stopping portion 28 directed upward to a position
c1 to 28c4 are formed. This protrusion stop portion 28c
The height of 1-28c4 is about 10 mm, and a through hole for screwing is formed in the center of the protrusion stopping portion 28c1-28c4. And the condensed water capturing plate 2
8 is the protrusion stopping portion 28c1 to 28c1 as shown in FIG.
28c4 abuts on the upper wall 24 and is fixed by screws. As a result, an air flow path is formed between the condensed water capturing plate 28 and the upper wall 24. The upper wall 24 is inclined so that the back side is slightly lower, and the dew condensation water captured by the dew condensation water capturing plate 28 flows down to the back side.

The left side wall 2 of the storage box 20 in the heat insulating box 10
The evaporator 51 of the cooling mechanism 50 that cools by the heat of vaporization of the refrigerant is fixed to the wall portion facing 2 with its air flow path oriented vertically, and the evaporator 51 and the left side wall 22 of the storage box 20. Between them, there is an air circulation hole 6 at the top.
1 is formed and a shielding plate 60 having a blower fan 62 arranged in the air circulation hole 61 is fixed at its upper side so as to hang from the upper wall of the inner box 12 in the heat insulating box 10. A sufficient gap is formed between the lower side of the shielding plate 60 and the lower wall of the inner box 12, and an air cooling flow passage communicating from the gap to the upper air circulation hole 61 via the air flow passage of the evaporator 51. Is formed.

The cooling mechanism 50, as shown in FIG. 13, condenses the compressor 52 for compressing the vaporized refrigerant supplied from the evaporator 51 and the compressed refrigerant compressed by the air cooling fan 53. Condenser 54 and dryer 55 for dehumidifying the condensed condensed refrigerant
The capillary tube 56 for converting the dehumidified condensed refrigerant into a low-temperature and low-pressure refrigerant and supplying it to the evaporator 51 is housed in an auxiliary box 10a formed on the left side of the heat insulating box 10.

A hot gas valve 57 is interposed between the output side of the compressor 52 and the input side of the evaporator 51. When the hot gas valve 57 is opened, the high temperature compressed refrigerant compressed by the compressor 52. Is the evaporator 5
1 to heat the evaporator 51. That is, the hot gas valve 57 can be opened and closed to make the cooling mechanism 50 a heating mechanism. Therefore, in this embodiment, the thawing promotion mechanism is constituted by the internal fans 30a and 30b and the heating mechanism.

Inside the chambers RM1 and RM2, sensors Th1 and Th2 for detecting the inside temperatures T1 and T2, respectively, are arranged, and the sensors Th1 and Th2 are connected to an electric control circuit 70 shown in FIG. ing. Then, the CPU 71 in the electric control circuit 70 detects the detected internal temperature T1,
A program corresponding to the flowcharts shown in FIGS. 15 and 16 is executed based on T2. The electric control circuit 70 is housed in the auxiliary box 10a.
In addition to the sensors Th1 and Th2, the internal fans 30a and 30b, the selection switch Sw for selecting the operation of the internal fans 30a and 30b, the compressor motor Cm of the cooling mechanism 50, and the hot gas valve 57 ( HV)
And are connected. The compressor motor Cm and the air cooling fan 53 are connected in parallel so that the air cooling fan 53 operates when the compressor motor Cm operates.

Next, the operation of this embodiment having the above structure will be described. When the main power switch (not shown) is turned on after the refrigerator is installed, CP in the electric control circuit 70 is turned on.
U71 starts the execution of the main program corresponding to the flowchart shown in FIG. 15, and first, in the initialization processing of step 100, clears various variables and flags. Here, as the flags, there are a start flag SF that is used when it is determined to start thawing, and an operation flag DF that is used to determine whether or not the cooling operation is performed, and the variables are timers used for the software timer. Counter Tc and the like. Then, as an initial setting, the start flag SF is reset, the operation flag DF is reset, and the timer counter Tc is cleared.

After the initialization, the CPU 71 proceeds to step 11
At 0, the in-compartment temperatures T1 and T2 detected by the sensors Th1 and Th2 and the selection state of the selection switch Sw are input as data serving as a determination criterion for the following control. Step 120
Then, the CPU 71 compares the internal temperature T1 with the thawing start temperature L1 which is a criterion for thawing start, and determines whether the temperature is lower than the thawing start temperature L1. Room RM1, RM2
Is held within a set temperature range between the upper limit set temperature H0 and the lower limit set temperature L0, as shown in FIG. However, the thawing start temperature L1 is lower than the set temperature range and is not cooled immediately after the power is turned on, so the process proceeds to step 130.

In step 130, the internal fans 30a, 3
0b is for determining the condition of the selection switch Sw for manually operating 0b, and if the operation is not initially selected by this selection switch Sw, the process proceeds to step 14
Go to 0. In step 140, it is determined whether the start flag SF is set and the timer has not yet started. The start flag SF is set when it is determined Yes in step 120 or step 130, and is not yet set in this determination. Therefore, the process proceeds to step 150.

In step 150, the timer counter Tc
Based on the value of, it is determined whether the timer is over time. This timer represents non-time counting when the timer counter Tc is "0", and represents a non-time counting when the timer counter Tc has a positive value. Since the timer counter Tc remains cleared in the initial setting,
This time, it is not timed and the process proceeds to step 170.

In step 170, it is determined whether or not the cooling operation is being performed based on the state of the operation flag DF. The operation flag DF is reset in the initial setting, and this reset state indicates that the cooling operation is not performed.
1 indicates that the inside temperature T1 is the upper limit set temperature H in step 190.
Determine if it is higher than zero. Immediately after the power is turned on, the inside of the refrigerator has not been cooled yet, so it is judged to be high, and the operation of the compressor motor Cm is started in step 192, and the operation flag DF is set in step 194 to perform cooling operation. Let me tell you that.

When the compressor motor Cm starts operating, the air cooling fan 53 also starts operating, and the blower fan 6
2 transfers the air in the air circulation passage W to the evaporator 51.
The cool air is circulated around the outer circumference of the storage box 20 while passing through it for cooling. When step 194 ends, the process returns to step 110 and the above-described processing is repeated. However, next, when it is determined in step 170 whether or not the cooling operation is being performed, since the cooling operation has already been started, the process proceeds to step 180 and the internal temperature T1 is not lower than or equal to the lower limit set temperature L0. To determine. When the cooling by the cooling mechanism 50 progresses and the temperature in the storage box 20 gradually decreases and falls below the lower limit of the set temperature range, the operation of the compressor motor Cm is stopped in step 182, and the operation is performed in step 184. Reset the flag DF.

By repeating the above, the internal temperature T1
Is maintained within a range between the upper limit set temperature H0 and the lower limit set temperature L0, as shown in FIG. By the way, when the user stores the frozen lump in the chamber RM2 in order to thaw it, the cold temperature of the frozen lump causes the temperature T2 inside the chamber RM2 to rapidly decrease. On the other hand, the chamber RM1 is separated from the chamber RM2 only by the partition wall 27, and since the partition wall 27 is formed of a heat conducting member, the chamber RM1 is cooled as the internal temperature T2 of the chamber RM2 decreases. The internal temperature T1 also begins to drop.

When the internal temperature T1 of the chamber RM1 decreases and becomes lower than the lower limit set temperature L0 or less, the operation of the cooling mechanism 50 is stopped as described above, and when it further decreases to the thawing start temperature L1 or less, the CPU 71 Determines that the thawing start temperature has been detected in step 120, and the start flag SF is set in step 122. Then, step 140
Then, it is determined that the start flag SF is set, and since the timer counter Tc is cleared, it is determined that the timer is off, and the process is step 142.
Proceed to.

In step 142, the CPU 71 substitutes "1" into the timer counter Tc to start the timer, and in step 144, the internal fan 30a, to accelerate the thawing.
Start 30b. The internal fans 30a and 30b are the room RM
The air in 2 is sucked in from below the cover 40 and the cover 4
0 is vented into the chamber RM2 from the ventilation hole 41 to circulate cool air. Then, cold air is sent around the frozen mass, and thawing can be promoted.

Further, a part of the air delivered by the internal fans 30a, 30b enters the air passage formed above the dew condensation water catching plate 28 and comes out from the vicinity of the partition wall 27, so that the inside of the chamber RM2. Air can be circulated throughout. At this time, if an ordinary duct for forming the air flow path is used, the storage space in the storage space is reduced, but by using the plate-shaped dew condensation water catching plate 28, the air flow path is space-saving. Can be formed. The condensed water capturing plate 28 includes a base plate 28b and a thin plate 28a.
Condensed water is trapped in a minute gap formed between and to prevent dripping.

When air is blown to the frozen mass, the odor may be added to the cold air, but in this embodiment, the chambers RM1 and RM2 are used.
Since they are airtightly separated, they can be thawed in a non-wrapped state. Although thawing can be promoted simply by operating the internal fans 30a and 30b, in the present embodiment, the cooling mechanism 50 is used as a heat pump when the inside of the storage box 20 is at a low temperature. In particular,
In step 146, all rooms RM1, RM2 in the storage box 20
Determine whether the temperature is lower than the thawing start temperature,
Step 1 only if M1 and RM2 are cold
Open the hot gas valve HV at 47 and perform step 1
At 48, the operation of the compressor motor Cm is started. Then, the refrigerant compressed by the compressor 52 and having a high temperature is directly supplied to the evaporator 51.
While the air is heated, the blower fan 62 supplies the air in the air flow circulation passage W. As a result, the air in the air circulation passage W is heated and warms the inside of the storage box 20 from the outer peripheral side.
In this way, the conditions for promoting the thawing are the storage box 2
Since all the chambers RM1 and RM2 in 0 are lower than the thawing start temperature, when the temperature inside the storage box 20 is high, the thawing is started and the temperature inside the storage chamber rises. It prevents things from happening.

Once the start of thawing is determined in this manner, even if the thawing start temperature is detected in step 120, the timer is counting and the above-mentioned thawing start processing is not repeated. When the timer counter Tc has a positive value, the CPU 71 indicates that the time is being measured.
After it is determined whether or not the timer is counting, the value of the timer counter Tc is incremented by "1" at step 152.
Then, at step 160, the timer counter Tc
Based on the value of, it is determined whether or not the timer has timed. The timer counter Tc is designed to be incremented by "1" in step 152 during counting.
Whether or not the timer has finished counting is determined by comparing the value of the timer counter Tc with an integrated value representing a predetermined time. If a value equivalent to 30 minutes is set as the same integrated value, the timer counter Tc
Value exceeds the same integrated value and it is judged that the timer has finished counting.

When the CPU 71 determines in step 160 that the timer has finished counting, it stops the mechanism for promoting the thawing in step 162 and thereafter. That is, the internal fans 30a and 30b are stopped in step 162, the hot gas valve HV is closed in step 164, and step 166 is performed.
Then, the compressor motor Cm is stopped. Further, in the following step 168, the timer counter Tc used for the defrosting promoting process is cleared, and in step 169, the start flag S
Reset F to prepare for the next start of thawing.

After the timer has finished, if the temperature inside the chamber RM1 has risen to the set temperature range, normal refrigeration is carried out, but if it is still lower than the thawing start temperature L1 at that point, the procedure described above is repeated. Executes the process to accelerate thawing. Therefore, if the time measured by the timer is set to be short, it is possible to frequently determine the temperature in the refrigerator and determine whether or not to accelerate the thawing. On the other hand, when it is desired to set the time measured by the timer to be long, the timer counter Tc is incremented in step 152 and then step 146 is performed.
Similar to the above, it is judged whether the temperature in all the rooms RM1 and RM2 is low, and if at least the temperature in all the rooms RM1 and RM2 is not low, stopping the food only in the warming mechanism can save the food in the cold storage well. it can.

By the way, there is a time difference between the timing at which the internal temperature T1 of the chamber RM1 decreases and the timing at which the frozen mass is stored in the chamber RM2. Therefore, if it is always tried to determine the start of thawing only by the internal temperature T1, as shown in FIG. 17, the end of thawing tends to be delayed by this time difference. However, in the present embodiment, the selection switch Sw is provided, and when the user stores the frozen mass in the room RM2, the selection switch Sw can be used to instruct thawing. In step 130, the CPU 71 determines whether or not the selection switch Sw is turned on. When the selection switch Sw is turned on, the start flag SF is set in the same manner as when the defrosting start on is detected. As a result, as shown in FIG. 17, the thawing process is immediately executed, and the thawing delay due to the above-mentioned time difference does not occur.

In the above-described embodiment, the case where the storage chamber is divided into two chambers has been described. However, even in the case of one chamber, it is possible to detect the temperature decrease and operate the thawing promotion mechanism. it can. Further, when two chambers are provided, only one of them may be used as a defrosting chamber, and another chamber may be provided with an internal fan so as to be a defrosting chamber. Further, the dew condensation water catching plate 28 may be mounted not only in one room but also in another room.

[Brief description of drawings]

FIG. 1 is a front view of a refrigerator according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway front view of the refrigerator.

FIG. 3 is a partially cutaway top view of the refrigerator.

FIG. 4 is a diagram showing a configuration of a cooling mechanism.

FIG. 5 is a circuit diagram of an electric control circuit.

FIG. 6 is a diagram showing a state of temperature control.

FIG. 7 is a diagram showing a relationship between the internal temperature and the operation of the internal fan, and the like.

FIG. 8 is a flowchart corresponding to determination of a fan start condition by software control.

FIG. 9 is a partially cutaway front view of the refrigerator according to the second embodiment of the present invention.

FIG. 10 is a partially cutaway top view of the refrigerator.

FIG. 11 is a perspective view of a dew condensation water catching plate.

FIG. 12 is a cross-sectional view showing an attachment structure of a condensed water capturing plate.

FIG. 13 is a schematic configuration diagram of a cooling mechanism.

FIG. 14 is a block diagram showing a control system in the refrigerator.

FIG. 15 is a flowchart of a main program executed by a CPU.

FIG. 16 is a flowchart of temperature control processing.

FIG. 17 is a diagram showing a change in the temperature inside the refrigerator which is temperature-controlled.

[Explanation of symbols]

 <First embodiment> 20 ... Storage boxes 30a, 30b ... Inside fan 71a ... Temperature control sequence circuit 71b ... Inside fan control sequence circuit Th1 to Th4 ... Temperature sensor TH ... Set upper limit temperature TL ... Set lower limit temperature TS ... Fan starting temperature <Second embodiment> 20 ... Storage boxes 30a, 30b ... Internal fan 70 ... Electric control circuit 71 ... CPU 72 ... Temperature indicators Th1, Th2 ... Sensor

Continuation of the front page (31) Priority claim number Japanese Patent Application No. 4-151327 (32) Priority date Hei 4 (1992) May 18 (33) Priority claim country Japan (JP)

Claims (5)

[Claims] 1. A refrigerator for cooling the inside of a storage box, a thawing promotion mechanism for accelerating thawing in the storage box, a temperature detecting means for detecting a temperature in the storage box, and a temperature detecting means for detecting the temperature. A refrigerator comprising: a thawing control means for activating the thawing promoting mechanism when the temperature of the inside of the storage box decreases more than normal cooling. 2. The refrigerator according to claim 1, wherein:
The defrosting control means determines that the way the temperature in the storage box is lowered is larger than the normal cooling when the temperature in the storage box detected by the temperature detection means becomes lower than a predetermined temperature. A refrigerator characterized by being configured. 3. The refrigerator according to claim 2, wherein:
When the temperature in the storage box detected by the temperature detection means is lower than a predetermined temperature below the holding temperature range in normal times, the defrosting control means normally decreases the temperature in the storage box. A refrigerator characterized by being configured so as to be judged to be larger than cooling. 4. The refrigerator according to claim 2 or 3, wherein the thawing control means controls the thawing control means when the temperature in the storage box detected by the temperature detection means becomes lower than the predetermined temperature. A refrigerator characterized in that it is configured such that it is determined that the temperature decrease in the storage box is larger than the normal cooling. 5. The refrigerator according to claim 1, wherein:
The thawing control means detects the degree of change in the temperature in the storage box detected by the temperature detecting means, and when the detected degree of change shows a sharp drop below a predetermined degree of change, the storage is performed. A refrigerator characterized in that it is configured so that it is judged that the way the temperature in the box drops is larger than the normal cooling.