JPH05322418A - Refrigerator - Google Patents

Abstract

PURPOSE:To preserve food in a condition suitable for cold storage after completion of thawing by stopping the heating of storing box adapted to be indirectly cooled by the chilled air flowing along the outer periphery thereof after the interior of both a thawing chamber and a refrigerating chamber into which the storing box is divided reaches a temp. suitable for the cold storage. CONSTITUTION:A metal plate-made storing box 20 is placed in an insulating case 10 and an air flow circulating passage W is formed therebetween. The storing box 20 is divided by a metal plate-made partition 27 into a refrigerating chamber RM1 and a thawing chamber RM2 and an evaporator 51 of a cooling chamber 50 is fixed to a place of the insulating case 10 opposite to the one side wall of the storing box 20. The chambers RM1 and RM2 are provided with temp. sensors Th1 and Th2 in its interior, respectively, and the temp. control is effected through a control circuit based on the output from such sensors. At the time of thawing, a hot gas valve is opened to introduce a high temp. regrigerant into the evaporator 51 and thereby heat the storing box 20 in order to accelerate the thawing and, when each of the temp. sensors Th1 and Th2 reaches at least a predetermined temp., the heating action is stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator, and in particular,
The present invention relates to a refrigerator in which cool air is circulated around the storage box to indirectly cool the inside of 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 a 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. Then, the convection fan blows the cool air, which tends to stay in the lower part of the storage box in a natural state, toward the upper part to make the temperature in the storage box uniform.

[0004]

Thus, the refrigerator which indirectly cools the inside of the storage box is characterized in that the inside of the storage box is maintained at a high humidity, and in particular, the air in the storage box is blown. It has been found that, if it is circulated, it is suitable for thawing a large-sized frozen product because the time can be shortened, but for normal refrigerated storage, the airless state is better because less water is evaporated from the refrigerated product.

For this reason, the applicant of the present invention first divides the inside of the storage box into a plurality of small chambers by partition walls made of a heat conducting member, and
A patent application (Japanese Patent Application No. 3-190800) was filed for an invention of a refrigerator in which an internal fan is provided in one small chamber, and a wind chamber suitable for thawing and a windless chamber suitable for refrigeration are formed. There is. With such a configuration, the frozen product can be efficiently thawed in the wind chamber, and the cold heat of the frozen product is supplied to the windless chamber through the partition wall to cool the windless chamber without operating the cooling mechanism. You can

However, if the amount of cold heat of the frozen product housed in the wind chamber is large, the airless chamber may be overcooled, and the perishable products stored in the airless chamber may freeze. The present invention has been made in view of the above problems, and aims to improve the efficiency of thawing and refrigeration,
Moreover, it is an object of the present invention to provide a refrigerator capable of storing refrigerated food at an appropriate temperature.

[0007]

In order to achieve the above object, the invention according to claim 1 sends cooling air to the outer circumference of a storage box made of a heat conducting member having an internal fan therein, In a refrigerator that cools the inside of a storage box, the partition is arranged in the storage box and partitions the inside of the storage box into small chambers, and the partition wall is composed of a heat conducting member that forms a defrosting chamber having the internal fan; Heating means for heating the inside of the storage box,
Defrosting chamber temperature detecting means for detecting the temperature inside the defrosting chamber, refrigerating chamber temperature detecting means for detecting the temperature inside the refrigerating chamber adjacent to the defrosting chamber through the partition, and the defrosting chamber temperature detecting means. And a heating stop means for stopping the heating means when the inside temperatures of the defrosting room and the refrigerating room are both above a predetermined temperature based on the detection result of the refrigerating room temperature detecting means. is there.

[0008]

In the invention according to claim 1 configured as described above, the defrosting chamber formed by the partition wall in the storage box is provided with the internal fan, and the frozen product is stored in the defrosting chamber. Activating the inner fan is suitable for thawing frozen products. Further, when the internal fan is operating, the air cooled by the frozen material is circulated in the thawing chamber, and the circulated air cools the partition wall and wall material made of the heat conducting member to cool the frozen material. The adjacent refrigerating compartments are cooled by. Further, during thawing, the inside of the storage box is heated to promote thawing in the thawing chamber and prevent the chilling chamber from becoming unsuitable for refrigeration. On the other hand, since the temperature of the thawing room and the refrigerating room are detected and heating is stopped after both temperatures exceed a predetermined temperature, only one room is still cold when heating is stopped, and the other room after heating is stopped. Will not be cooled and unsuitable for storage.

[0009]

As described above, according to the present invention, high-humidity air is blown to promote thawing, the cold heat of the frozen product is effectively used, and the temperature inside the thawing chamber and the refrigerating chamber is controlled. Since the heating is stopped after both are in a state suitable for refrigeration, it is possible to provide a refrigerator that can be surely stored in a state suitable for refrigeration at the end of thawing.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 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 body includes a heat insulation box 10 and a storage box 20.
The heat insulation box 10 has an inner wall of an outer box 11 and an inner box 1
2 is formed by filling a heat insulating material 13 such as urethane foam between the outer wall and the outer wall, and a pair of left and right openings 14a, 1 is formed on the front surface.
Heat insulating doors 15a and 15b that form 4b and open and close the openings 14a and 14b 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 good heat conducting member, into a housing having an opening 21 on one surface.
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 and 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 good heat conducting member, is fixed to the upper wall 24 and the bottom wall 25 of the storage box 20 at the upper and lower sides, respectively. The inside is divided into a room RM1 (refrigerating room) on the right side in the figure and a room RM2 (thawing room) on the left side in the figure. In each of the compartments RM1 and RM2 divided in this way, the respective internal temperatures T1 and T2
Temperature sensors Th1 and Th2 for detecting the temperature are arranged.

Two internal fan 30 (30a, 30b)
Are each configured by fixing the fan 32 to the rotation axis of the fan motor 31, and are attached to the left side wall 22 via a supporting member so as to face the partition wall 27.
Further, a cover 40 for forming an air flow path is attached to the front surfaces of the internal fans 30a and 30b,
The cover 40 has an exhaust port 4 at a portion facing the fan 32.
1 is formed, and a suction port 42 is formed in the lower part. That is, the edge of the upper side of the cover 40 is the upper wall 2.
4, the end of the left side, which is bent as an L-shaped cross section, contacts the left side wall 22 of the storage box, the end of the right side contacts the rear wall 26 of the storage box 20, and the lower side defines the left side wall 22 and the predetermined side. The suction port 42 is formed with a gap.

The left side wall 2 of the storage box 20 in the heat insulating box 10
An 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. A flow hole 61 is formed, and a shield plate 60 having a blower fan 62 is fixed to the air flow hole 61. A sufficient gap is formed between the lower side of the shielding plate 60 and the lower wall of the inner box 12, and the upper air circulation hole 6 is formed from the gap through the air flow path of the evaporator 51.
1 forms an air cooling flow path communicating with 1.

As shown in FIG. 4, the cooling mechanism 50 includes a compressor 52 for compressing a refrigerant, a condenser 54 for condensing the compressed refrigerant under compression by an air cooling fan 53, and a condensing condenser for the same. 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.

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. The hot gas valve 57 opens when energized and closes when de-energized.

The compressor 52 is a compressor motor 5
2a and a compression mechanism 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 an electric control circuit 70 as shown in FIG. In addition to this, the electric control circuit 70 includes the temperature sensors Th1 and Th2.
The internal fan 30a, 30b, the hot gas valve 57, the blower fan 62, and the selection switch SW for selecting the operation of the internal fan 30a, 30b are connected, and the CPU 7
1 executes a program corresponding to the flowcharts shown in FIGS. 6 and 7 to control these input / output devices. The internal fans 30a and 30b, the air-cooling fan 53, and the blower fan 62 each rotate and blow when they are energized by the electric control circuit 70. The selection switch SW is provided with an operator 34a on the front surface of the auxiliary box 10a, and the operator 34a is operated to select the operation of the in-compartment fans 30a and 30b.

Next, the operation of this embodiment having the above configuration will be described. When the main power switch (not shown) is turned on, C
The PU 71 starts executing the main program corresponding to the flowchart shown in FIG. First, in step 100, the CPU 71 initializes variables and flags used for executing this program. In this program, a cooling operation flag DF indicating whether or not the cooling mechanism 50 is operated to perform the cooling operation and a timer counter TC used for a software timer are used, and the cooling operation flag DF includes The non-operation state (OFF) is set, and the timer counter TC is set to "0" indicating the non-timekeeping state.

Next, in step 200, the CPU 71 inputs the inside temperatures T1 and T2 of the temperature sensors Th1 and Th2 and the selection status of the selection switch SW. And the CPU 71
In step 250, it is determined whether or not the thawing operation is in progress based on the value of the timer counter TC that represents the duration of the thawing operation. Initially, the timer counter TC is set to "0".
Is set, which means that the thawing operation is not in progress as described later. Therefore, the CPU 71 determines that the thawing operation is not in progress and executes the temperature control routine of steps 300 to 360 based on the internal temperature T1 of the temperature sensor Th1.

In the temperature control routine, the CPU 71 determines in step 300 based on the setting of the cooling operation flag DF whether or not the cooling operation is being performed. Immediately after the power is turned on, the cooling operation flag DF is in the non-operation state (OFF)
Is set, the CPU 71 determines that the cooling operation is not performed, and in step 340, the internal temperature T
It is determined whether 1 is higher than the upper limit set temperature H0 shown in FIG. Upper limit set temperature H0 and lower limit set temperature L shown in FIG.
0 is set within a range of several degrees with 0 ° C. as a reference, and as long as it is within this temperature range, the chambers RM1 and RM2 are in a state suitable for refrigeration storage.

By the way, since the internal temperature T1 should be the same as the indoor temperature, it should be higher than the upper limit set temperature H0 suitable for refrigerated storage, and the CPU 71 starts the cooling operation in step 350. Specifically, the CPU 7
1 is from the electric control circuit 70 to the compressor motor 52
Energization of a, the air cooling fan 53, and the blower fan 62 is started. As a result, the cooling mechanism 50 operates and the blower fan 62 blows the air in the airflow circulation passage W to the cooled evaporator 51. Then, the air in the air circulation passage W is cooled, and further, when it flows around the storage box 20 made of a heat conducting member, the chambers RM1 and RM2 are cooled via the wall material.

After starting the cooling operation, the CPU 71 sets the cooling operation flag DF to the operating state (ON) in step 360.
If is set, the temperature control routine is terminated for the time being, and the control proceeds to step 400 and subsequent steps. However, the next time this temperature control routine is executed, the cooling operation flag DF is set to the operating state (ON), so CP
U71 determines in step 300 that the cooling operation is being performed, and proceeds to step 310 to determine whether the internal temperature T1 is lower than or equal to the lower limit set temperature L0. As the cooling operation progresses, the chambers RM1 and RM2 are gradually cooled,
While the temperature is lower than the lower limit set temperature L0, the temperature control routine is terminated without doing anything. Then, when the temperature becomes equal to or lower than the lower limit set temperature L0, the process proceeds from step 310 to step 320, and the cooling operation is stopped. That is, energization to the compressor motor 52a and the air cooling fan 53 is stopped to stop the operation of the cooling mechanism 50, and energization to the blower fan 62 is stopped to stop the air blowing in the air flow circulation passage W.
Further, the CPU 71 sets the cooling operation flag DF to the non-operation state (OFF) to indicate that the cooling operation is stopped in step 330.

When the cooling operation is stopped, the temperature inside the chambers RM1 and RM2 gradually rises due to the infiltration heat from the outside of the heat insulating box. Since the cooling operation flag DF is set to the operating state (OFF), as shown in FIG. 8, when the temperature of the chambers RM1, RM2 rises and exceeds the upper limit set temperature H0, the CPU 71 described above in step 350. Thus, the cooling operation is started. Thereafter, the CPU 71 repeats the above-described processing to execute temperature control so that the internal temperatures of the chambers RM1 and RM2 are maintained between the upper limit set temperature H0 and the lower limit set temperature L0.

By the way, it is assumed that a frozen chunk, which is a frozen chunk of meat, is stored in the chamber RM2 at the timing e shown in FIG. 8 and the selection switch SW is operated. Then, the CPU 71 inputs the selection status of the selection switch SW in step 200, and determines in step 400 whether the selection switch SW is turned on and the timer has not started counting time. Whether or not the timer is counting is determined by whether or not the timer counter TC has a positive value. Initially, the timer counter TC is set to “0” in the initial setting, so that the timer is not timing and the selection switch SW
Is operated, the CPU 71 causes the step 41
At 0, the timer counter TC is set to "1" and the timer counter is started. As a result, the timer counter TC has a positive value and is incremented by "1" at every predetermined timing, so that the integrated value thereof represents an approximate time count.

Further, in step 420, it is judged whether or not the cooling operation is in progress based on the cooling operation flag DF. If it is in the cooling operation, the cooling operation is stopped in step 430, and the cooling operation flag DF is not operated in step 440. Set to the state (off). On the other hand, when the timer is started, the CPU 71 starts the defrosting operation in step 450. In the thawing operation, the internal fans 30a and 30b are operated, and the chambers RM1 and RM2 are externally heated to accelerate the thawing in the chamber RM2 and prevent the freezing trouble in the chamber RM1. Specifically, the CPU 71 controls the internal fans 30a, 30
b is operated to forcibly circulate the air in the chamber RM2, the compressor motor 52a and the blower fan 62 are energized to be operated, and the hot gas valve 57 is energized to operate the output side of the compressor 52 and the input side of the evaporator 51. And communicate with.

When the internal fans 30a, 30b operate in the room RM2, the internal fans 30a, 30b blow the high-humidity air in the room RM2 to the surface of the frozen mass, so that the water in the air is frozen. Condensation, freezing and frost on the surface of.
The frost is blown away by the air blown by the internal fans 30a and 30b, and the above cycle is continuously repeated to facilitate freezing of new moisture, and the frozen mass is thawed by being heated by the latent heat of steam.

On the other hand, since the air in the chamber RM2 is cooled by the surface of the frozen mass, the temperature drops sharply as shown in FIG. Since this cooled air is circulated in the room RM2 by the internal fans 30a and 30b, the surrounding walls 22 and 2
The air in the air circulation passage W is cooled via 4, 25 and 26, and the air in the chamber RM1 is cooled via the partition wall 27.

By the way, when the hot gas valve 57 is opened and the output side of the compressor 52 is directly connected to the evaporator 51, the high temperature refrigerant compressed by the compressor 52 is supplied to the evaporator 51, and the evaporator 51 is connected.
To heat. In addition, the blower fan 62 is connected to the air flow circulation passage W.
By supplying the air in the evaporator 51 to the same, the air is warmed, and when the air is circulated around the outer circumference of the storage box 20, the chamber RM
1, warm the inside of RM2.

Therefore, in the chamber RM2, the thawing is promoted by the heating from the evaporator 51, and in the chamber RM1, even if the chamber RM2 is cooled by heating, the refrigeration obstacle does not occur. You can When the thawing operation is started, the temperature control routine is not executed by the judgment in step 250, and the control for starting the thawing operation is not executed by the judgment in step 400. Then, if the value of the timer counter TC is positive in step 500, it is determined that the timer is counting time, the value of the timer counter TC is incremented by "1" in step 510, and the value is incremented in step 520. The subsequent value is compared with the integrated value representing the predetermined expiration time to determine whether the timer has expired.

The expiration time is set to a time suitable for thawing a normal frozen mass, and is set to, for example, about 10 to 30 minutes. Then, how many times the CPU 71 repeats step 510 within this expiration time is an integrated value corresponding to the expiration time. In step 520, it is determined whether the timer has expired using this integrated value. Assuming that the timer expiration time is t minutes, the room RM1, RM2
It is assumed that the internal temperatures T1 and T2 of the refrigerator are as shown in FIG. As shown in the figure, in this state, the inside temperature T1 of the chamber RM1 is lower than the lower limit set temperature L0 suitable for cold storage, and the inside temperature T2 of the chamber RM2 is even lower.
Therefore, if the thawing operation is ended, a low temperature obstacle occurs in the room RM1, and the thawing is not promoted in the room RM2, and a long time is required until the end.

As described above, if it is determined whether or not the decompression has been completed based only on the time, the decompression will be completed in the undecompressed state. On the other hand, the temperature inside the chambers RM1 and RM2 gradually approaches as the end of the thawing, and basically rises gradually due to the infiltration heat from the outside.
It is not always necessary to complete the thawing after the lower limit set temperature L0 or higher.

In the present embodiment, in view of these situations, the first end temperature E1 is set as the internal temperature of the chamber RM1 (refrigerating chamber) sufficient to complete the thawing, and the chamber RM2 is similarly set.
The second end temperature E2 is set as the internal temperature of the (thawing chamber). Then, after the timer expires, the CPU 71 determines in steps 530 and 540 whether or not the in-compartment temperatures T1 and T2 are equal to or higher than the predetermined temperatures E1 and E2, respectively. At the timing g, the internal temperature T2 of the chamber RM2 exceeds the second end temperature E2, but the internal temperature T1 of the chamber RM1 does not exceed the first end temperature E1. Then, at the timing h, the internal temperatures T1 and T2 of the chambers RM1 and RM2 exceed the respective end temperatures E1 and E2, and step 550 is executed to end the above-mentioned thawing operation.

When the CPU 71 completes the defrosting operation at step 550, it goes to step 560 to set the timer counter T.
C is set to "0" to clear it, and control is returned to step 200. Therefore, from the next time, the normal temperature control routine is executed, and when the selection switch SW is operated, various controls for starting the thawing operation are executed.

Although software control by a microcomputer is executed in the above embodiment,
It can also be executed by wire logic control. Further, in the present embodiment, the expiration time of the timer is made to coincide with the approximate defrosting time, the defrosting is continued until the expiration time ends, and after the timer expires, the internal temperatures T1, T2 of the chambers RM1, RM2.
Is over the end temperatures E1 and E2. However, the timer is provided to prevent the end of thawing from being determined during the temperature decrease that occurs within a short period of time after storing the frozen mass, and may be set to a shorter time.

On the other hand, in the above-described embodiment, the chamber RM2
Although the internal fans 30a and 30b are installed inside, the room RM
The internal fans 30a and 30b may be provided in the unit 1 to form a thawing chamber. Further, although the two in-compartment fans 30a and 30b are arranged above and below, it is also possible to arrange only one below and blow out the air upward. Further, the blowing direction may be directed to the partition wall 27 so as to promote heat exchange by the partition wall 27.

Further, in the above-described 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 direction of partitioning is arbitrary, such as partitioning vertically instead of horizontally.

[Brief description of drawings]

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 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 flowchart corresponding to a main program executed by a CPU.

FIG. 7 is a flowchart corresponding to a main program executed by a CPU.

FIG. 8 is a diagram showing changes in the internal temperature.

[Explanation of symbols]

 RM1, RM2 ... Room 10 ... Insulation box 20 ... Storage box 30a, 30b ... Internal fan 50 ... Cooling mechanism 51 ... Evaporator 52 ... Compressor 57 ... Hot gas valve 62 ... Blower fan 70 ... Electric control circuit 71 ... CPU E1 ... No. One end temperature E2 ... Second end temperature Th1, Th2 ... Temperature sensor

Claims (1)

[Claims] 1. A refrigerator in which cooling air is blown to cool the inside of a storage box made of a heat conducting member having an internal fan inside to cool the inside of the storage box. The storage box is divided into small chambers, a partition wall composed of a heat conducting member that forms a thawing chamber having the above-mentioned internal fan, a heating means for heating the inside of the storage box during thawing, and a temperature inside the thawing chamber Of the defrosting chamber temperature detecting means, the defrosting chamber temperature detecting means and the refrigerating chamber temperature detecting means for detecting the temperature inside the refrigerating chamber adjacent to the defrosting chamber via the partition wall. A refrigerator comprising: a heating stopping means for stopping the heating means when both the inside temperature of the thawing chamber and the inside of the refrigerating chamber become equal to or higher than a predetermined temperature based on the detection result.