JPH0140264B2 - - Google Patents

Description

[Detailed description of the invention] <Technical field> The present invention relates to a refrigerator-freezer.

<Prior art> Conventionally, a refrigerator is equipped with a freezer compartment and a refrigerator compartment that communicate with each other through a cold air duct, and a quick-freeze box built into the freezer compartment. When performing quick freezing in a refrigerator-freezer that forcibly circulates cold air between the cold air duct and the refrigerator compartment, by operating the start button from the outside, the compressor is short-circuited for a set time, and the end is set. This was troublesome because the operator had to release the compressor by checking the food inside, and the compressor was not allowed to short-circuit even though the food inside had already been frozen. There were many cases where the

<Purpose> In view of the above, the present invention aims to provide a refrigerator-freezer that automatically performs quick freezing, eliminates external operations, and prevents wasteful operation of the compressor.

<Embodiment> Hereinafter, an embodiment of the present invention will be described based on FIGS. 1 to 5. In FIG. A refrigerating chamber 4 is sectioned in the lower part, and an evaporator 6 is disposed at the rear of a cold air circulation passage 5 at the lower part of the freezing chamber 3, and a blowing fan 7 is disposed above the evaporator 6.

Further, a vertical cold air duct 8 is formed at the rear of the main body 1 and communicates the freezer compartment 3 and the refrigerator compartment 4, and a damper device 9 for opening and closing the cold air duct 8 is provided at the lower part of the cold air duct 8. ing.

Further, a quick freezing box 11 is installed in the upper part of the freezing compartment 3 via a louver 10 in front of the blowing fan 7.
is installed. As shown in FIG. 2, the quick-freezing box 11 has a food entry/exit door 12 attached to the front surface so as to be openable and closable, and a cold air inlet 13 for introducing cold air from the blower fan 7 to the rear surface. Also,
A food plate 15 is placed on the bottom plate 14 of the quick freezing box 11, and a cold air outlet 16 is formed at the front of the bottom plate 14.

Further, the quick freezing box 11 has the cold air inlet 13.
A case 18 with a ventilation hole 18a containing a first temperature sensor 17 for sensing the temperature on the cold air inlet side is formed on the mouth wall of the case 18.

Further, a case 20 with a ventilation hole 20a is provided in the front part of the bottom plate 15, and a second temperature sensor 19 for sensing the temperature on the cold air outlet side is housed therein.

Further, a third temperature sensor 21 for sensing the temperature inside the refrigerator compartment 4 is provided at the rear part of the main body 1 on the refrigerator compartment 4 side.

Then, the cold air passes through the quick freezing box 11 from the evaporator 6, circulates through the freezing compartment 3, and also flows into the cold air duct 8.
It also enters the refrigerator compartment 4 and returns to the evaporator 6 again.

The opening/closing operation of the damper device 9 and the operation of the compressor 29 that feeds refrigerant into the evaporator 6 are controlled by a control device 22 .

As shown in the functional block diagram of FIG. 6, this control device 22 determines rapid freezing when the temperature difference ΔT between the first temperature sensor 17 and the second temperature sensor 19 exceeds a large first set value A. When the temperature difference ΔT between the rapid cooling start temperature difference determining means 22a, the first temperature sensor 17, and the second temperature sensor 19 becomes equal to or less than the small second set value B (almost zero), rapid freezing is performed. A quenching end temperature difference determining means 22b that determines that the quenching has ended, and a quenching start temperature difference determining means 2
The damper device 9 is closed by the rapid cooling start signal of 2a, and the normal state (state that does not require rapid freezing operation) is determined by the rapid cooling end signal of the rapid cooling end temperature difference determining means 22b, and the temperature detected by the third temperature sensor 21 is reached. Based on this, the damper control means 22c opens and closes the damper device 9, and the compressor 29 is continuously operated according to the quenching start signal from the quenching start temperature difference determining means 22a, and the normal state is determined based on the quenching end signal from the quenching end temperature difference determining means 22b. 2nd temperature sensor 1
The compressor control means 22d is provided to cause the compressor 29 to be operated intermittently based on the detected temperature at step 9.

To explain the specific configuration of the control device 22 constituting each of the above-mentioned means, this control device 22 mainly includes a general one-chip microcomputer (hereinafter referred to as a microcomputer) 23, as shown in FIG.
Program ROM and data are stored inside the microcontroller.
It has RAM and ALU and is driven by a reference clock oscillator 24. The input section of this microcomputer 23 includes the first temperature sensor 17 (thermistor), the second temperature sensor (thermistor) 19, the third temperature sensor (thermistor) 21, and the temperature setting variable resistor 2.
5 and the signals from these are sent to an A/D converter 26
is converted into a digital value and input to the microcomputer 23. Further, the microcomputer 23 receives a signal from an external operation section 28 for manual setting located on the door section 27 of the refrigerator-freezer.

Note that the second temperature sensor 19 is connected to the compressor 2.
It also serves as a temperature sensor for the freezer compartment 3 to control the operation of the freezer compartment 9.

Furthermore, a compressor 29 is connected to the output section of the microcomputer 23 via a drive circuit such as an inverter, and four transistors TR1 to TR4 that drive a stepping motor 30 of the damper device 9 are connected to the It works by sending a number of pulses.

As shown in FIG. 4, the damper device 9 is composed of the stepping motor 30, a shaft 30a rotated by the motor 30, and a damper 31 attached to the tip of the shaft 30a.

That is, the rapid cooling start temperature difference determining means 22a
The quenching end temperature difference determining means 22b is constituted by an ALU of the microcomputer 23 or the like. Further, the damper control means 22c includes a part of the microcomputer 23, four transistors TR1 to TR4, and the like. Furthermore, the compressor control means 22d
It consists of a part of the microcomputer 23 and a compressor drive circuit (not shown).

Next, the operation of automatic rapid freezing will be explained based on FIGS. 3 and 5. FIG. 3 shows the temperature detected by the first and second temperature sensors 17 and 19 of the cold air duct 11 on the vertical axis, and the horizontal axis shows the series of time passages, and the open/closed state of the damper 31 accompanying this is shown on the bottom. This is shown in . In the figure, θ1 indicates the temperature of the second temperature sensor 19 on the cold air inlet side, and θ2 indicates the temperature of the first temperature sensor 17 on the cold air outlet side. FIG. 5 is a flowchart showing the rapid freezing operation.

Now, when the refrigerator-freezer is in normal operation, as shown in FIG. 3, there is no load inside the quick freezing box 11, so the cold air inlet and outlet temperatures θ1 and θ2 are almost equal, and the temperature difference ΔT is the first. Do not exceed set value A.
Therefore, in the quenching start temperature difference determining means 22a,
It is determined that the state is normal, and rapid freezing is not performed, but normal operation is performed. That is, in the compressor control means 22d in the microcomputer 23, the second temperature sensor 1
9 detects the temperature of the freezer compartment 3 and controls the operation of the compressor 29. Further, in the damper control means 22c, the third temperature sensor 21 detects the temperature of the refrigerator compartment 4 and causes the damper device 9 to perform normal opening/closing operations.

Next, when food to be quickly frozen (at room temperature) is placed in the quick-freeze box 11, a temperature difference ΔT is created between the inflow and outflow speeds θ1 and θ2 of cold air in the quick-freeze box 11 due to the heat generated from the food. The inflow temperature of the cold air is detected by the first temperature sensor 17 and the outflow temperature is detected by the second temperature sensor 19, respectively, and the temperature signals are input to the microcomputer 23 of the control device 22.
In the microcomputer 23, the rapid cooling start temperature difference determining means 22
Based on a, it is determined whether the input temperature difference ΔT between the inflow and outflow temperatures exceeds the first set value A.
Then, at time t1 when the first set value A is exceeded, the quenching start temperature difference determining means 22a causes the compressor control means 22 to
d and the damper control means 22c, and rapid freezing is started. At the start of this rapid freezing, first, the motor 30 is driven so that the damper 31 of the refrigerator compartment 4 is completely closed by a signal from the damper control means 22c of the control device 22. When this drive signal is sent out for a certain period of time (3 to 5 seconds) and the damper 31 is completely shut off, the compressor control means 22d of the microcomputer 23 drives the drive circuit of the compressor 29 to continuously operate the compressor 29. A signal is output. Therefore, the cold air does not go to the refrigerator compartment 4, but all circulates within the freezing compartment 3, and the quick freezing box 11
Freeze the food inside faster.

Then, the food is cooled little by little, the heat generated from the food decreases, and the temperature difference ΔT
When the value approaches zero and becomes equal to or less than the second set value B, the rapid cooling end temperature difference determining means 22b of the control device 22 determines that the rapid freezing has ended. Assuming that this time point is t2, normal operation resumes after this point. That is,
The third temperature sensor 21 detects the temperature inside the refrigerator compartment 4, and the damper control means 22c controls the damper 3.
1 will open again.

In this way, the quenching operation is automatically performed without any external confirmation of quenching settings and completion. Note that during the rapid cooling operation (t1 to t2), the compressor 29 is in continuous operation.

<Effects> As is clear from the above explanation, in the present invention, when the temperature difference between the cold air inlet and outlet side of the quick freezing box exceeds a large first set value, it is determined that quick freezing is occurring and the damper device is closed. and operate the compressor continuously,
In addition, when the temperature difference between the cold air inlet and outlet side of the quick freezing box becomes less than the second set value, it is determined that quick freezing has ended and the damper device and compressor are operated normally. When food is placed in a box, a series of rapid cooling operations can be performed automatically, eliminating the need for external operations.

Furthermore, since the compressor returns to intermittent operation when the freezing of the food in the quick-freeze box is completed, there is an excellent effect that the compressor can be efficiently controlled without unnecessary short-circuit operation of the compressor.

[Brief explanation of drawings]

Figures 1 to 6 show an embodiment of the present invention, in which Figure 1 is a vertical cross-sectional view of a refrigerator-freezer, Figure 2 is a perspective view of a quick-freezing box, and Figure 3 is a diagram of a quick-freezing box. A diagram showing the relationship between the temperature sensed by the first temperature sensor and the second temperature sensor and time and the corresponding opening/closing operation of the damper. Figure 4 is a circuit diagram of the damper control device, and Figure 5 is a flowchart of the control device. , 6th
The figure is also a functional block diagram of the control device. 1: refrigerator-freezer body, 2: partition wall, 3: freezer compartment, 4: refrigerator compartment, 6: evaporator, 7: ventilation fan,
8: cold air duct, 9: damper device, 17: first temperature sensor, 19: second temperature sensor, 21:
Third temperature sensor, 23: microcomputer, 29: compressor, 30: motor, 31: damper.

Claims (1)

[Claims] 1 Comprising a freezing compartment 3 and a refrigerating compartment 4 that communicate with each other through a cold air duct 8, and a quick freezing box 11 installed in the freezing compartment 3, cooling is achieved by evaporation of refrigerant sent from a compressor 29 to an evaporator 6. The cooled air is sent to the evaporator 6, quick freezing box 11,
A refrigerator-freezer that forcibly circulates between a freezing compartment 3, a cold air duct 8, and a refrigerator compartment 6 includes a damper device 9 that opens and closes the cold air duct, and a first temperature sensor 17 on the cold air inlet side of the quick freezing box 11.
, a second temperature sensor 19 on the cold air outlet side of the quick freezing box 11, a third temperature sensor 21 that senses the temperature inside the refrigerator compartment 4, and the damper device 9.
A control device 22 for controlling the opening/closing operation of the compressor 29 and the operation of the compressor 29 is provided, and the control device 22 includes:
The first temperature sensor 17 and the second temperature sensor 1
Rapid cooling start temperature difference determining means 22a determines that rapid freezing is occurring when the temperature difference ΔT between the first temperature sensor 17 and the second temperature sensor 19 exceeds a large first set value A, and the temperature difference ΔT between the first temperature sensor 17 and the second temperature sensor 19 Small second set value B
A quick-cooling end temperature difference determining means 22b determines that the quick freezing has ended when the temperature is below, and a quick-cooling end temperature difference determining means 22b closes the damper device 9 based on the rapid cooling start signal from the rapid cooling start temperature difference determining means 22a. damper control means 22 which determines the normal state based on the rapid cooling end signal and opens and closes the damper device 9 based on the temperature detected by the third temperature sensor 21;
c, the compressor 29 is continuously operated according to the quenching start signal from the quenching start temperature difference determining means 22a, and the normal state is determined based on the quenching end signal from the quenching end temperature difference determining means 22b, and based on the temperature detected by the second temperature sensor 19. A refrigerator-freezer characterized by comprising compressor control means 22d for causing the compressor 29 to operate intermittently.