JPH0570067B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rapid freezing device in which a direct cooling type auxiliary cooler is provided in a part of a freezer compartment used in a forced draft type refrigerator-freezer or the like.

Structure of the conventional example and its problems The conventional example will be explained with reference to FIGS. 3 and 4. Reference numeral 1 denotes a main cooler 4 housed in a cooling chamber 3 constructed within a partition wall 2, and is a forced draft type freezer in which cooled air is circulated to a freezing chamber 6 and a refrigerating chamber 7 by a blower 5. Reference numeral 6' denotes a quick-freezing room which is provided with an auxiliary cooler 8 of a direct cooling type separately within the freezer room 6, and allows food to be quickly frozen.

Furthermore, a damper thermostat 14 is provided at the entrance of the refrigerator compartment 7 to adjust the cold air inflow chamber. As shown in Fig. 4, the refrigeration cycle is as follows: compressor 9 → condenser 10 → first capillary → main cooler 4 →
Switching between a normal flow path that circulates with the compressor 9 and a rapid freezing flow path that circulates with the compressor 9 → condenser 10 → second capillary tube 12 → auxiliary cooler 8 → main cooler 4 → compressor 9 flow path control device 13 (hereinafter referred to as flow path switching valve 13)
), and by operating the flow path switching operation using this switching valve 13, a rapid freezing effect is performed.
During this rapid freezing, the compressor 9 and the blower 5 are forced to operate continuously to accelerate the freezing speed of the food that is in contact with the auxiliary cooler 8. However, since the blower 8 is continuously operated during rapid freezing to forcefully ventilate cold air, the temperature inside the refrigerator compartment decreases, causing the food being stored to freeze. Particularly when the outside temperature of the refrigerator is low, the temperature often decreases at an accelerated rate and adversely affects the food stored inside the refrigerator.

OBJECT OF THE INVENTION In view of the above points, an object of the present invention is to prevent overcooling in a refrigerator compartment during rapid freezing.

Structure of the Invention In order to achieve this object, the present invention stops the blower when the inside of the refrigerator compartment becomes supercooled during quick freezing, eliminates the ventilation of cold air in the refrigerator compartment, and continues quick freezing. In addition to preventing overcooling, the operation of the compressor is temporarily stopped when the temperature drops to a predetermined value to prevent overcooling.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Components that are the same as those in the prior art are designated by the same reference numerals and explanations will be omitted. In the figure, the compressor 9 is connected to a power source via a relay 15,
The blower 5 is maintained in parallel with the compressor 9 via a relay 16. The flow path switching valve 13 is connected in series with the relay 17 and then in parallel with the power source. The flow path switching valve 13 is configured to switch to the normal flow path when the coil is conducting, and to switch to the quick freezing flow path when the coil is not conducting. Next, a control device for driving these relays will be described. Reference numeral 19 is a temperature control device for the freezing compartment, and a thermistor 2 is installed in a part of the freezing compartment 12.
0, resistors R ₁ , R ₂ , R ₃ , and a comparator 21. The output of the comparator 21 is sent via an OR circuit 22 to a driver circuit (not shown) such as a transistor to send a signal to turn the relay 15 ON/OFF. The thermistor R _TH2 24 is a temperature control device for the refrigerator compartment, and the thermistor R _TH2 24 is a resistor installed near the damper thermostat 14 of the refrigerator compartment 7.
The outputs of R ₄ , R ₅ , R ₆ and the comparator 25 are configured to send a signal to turn ON/OFF the relay 16 via an AND circuit 26 and a driver circuit such as a transistor (not shown) via the blower timer 18. has been done. Further, the voltage dividing circuit including the thermistors R _TH2 24 and R ₄ is connected to the in-phase terminal of a temperature control device 29 for the refrigerator compartment, which is composed of resistors R ₁ , R ₈ and a comparator 30. The output of comparator 30 is
The output of the AND circuit 31, which is connected to the OR circuit 22 via the AND circuit 31, is connected to the input section of the AND circuit 26. 27 is a quick freeze switch,
Reference numeral 28 denotes a quenching time timer, which is connected to the input of the OR circuit 22 via an AND circuit 31 and constitutes a control device for the relay 15. After the quick-freezing switch 27 is turned on, the quick-cooling timer 28 receives a high signal (hereinafter simply referred to as "H") to start quick freezing at the a input, as shown in FIG. The b output is configured to output an "H" signal for, for example, 90 minutes during rapid freezing. And rapid cooling timer 2
The b output of 8 is the input of the OR circuit 22 and the relay 15
Sends a signal to turn ON/OFF, and output b is AND
It becomes an input to the circuit 26 and is connected to send a signal to turn the relay 16 ON/OFF via the blower timer 18.

Next, the operational status of this configuration will be explained.

Normally, if the internal temperature of the refrigerator (freezer compartment temperature) is higher than the predetermined value, the resistance value of the thermistor 20 R _TH1
has become smaller, and R _TH1 of the temperature control device 19
Since the voltage at point A determined by R ₁ is higher than the potential at point B determined by resistors R ₂ and R ₃ and the output of comparator 20 becomes "H", the output of OR circuit 22 also goes "H". Then, the relay 15 is turned on via a driver circuit (not shown) such as a transistor, and
Compressor 9 is operated. At this time, quick freeze switch 2
7 is in the OFF state, so the rapid cooling timer 28
b output is "L", the output of the AND circuit 31 becomes "L", the output of the AND circuit 26 indicates "L" regardless of the output of the comparator 25 of the refrigerator temperature control device 23, and the blower timer 18 c
When "L" is input to the terminal, the d output is always "H" from c and d in FIG. 2, and the relay 16 is turned on, and the blower 5 is operated by turning the relay 15 on and off. Also, the relay 17 is turned on at the same time, and the suction coil of the flow path switching valve 13 is energized, and the refrigerant circuit starts the circulation cycle of the compressor 9 → condenser 10 → first capillary tube 11 → main cooler 4 → compressor 9. Configure and cool.

After that, when the inside of the refrigerator is cooled to a certain temperature, the resistance value R _TH1 of the thermistor increases and the A potential becomes smaller than the B potential, the output of the comparator 21 becomes "L", and the b output of the quenching timer 28 becomes low. Together with the "L" signal, the output of the OR circuit 22 also becomes "L", and accordingly, the relay 15 is turned off and the compressor 9 and blower 5 are stopped. Thereafter, this action is repeated to perform the normal cooling action.

Next, the rapid freezing operation will be explained. If you turn on the quick freezing switch 27 at your discretion, the quick cooling timer 2 will start.
From Figure 2, the b output of 8 is “H” throughout the quenching time T.
Since the signal continues to be generated and the refrigerator compartment is not in a supercooled state, the output of the comparator 30 becomes "L".
The output of the AND circuit 31 is "H" and one input of the OR circuit 22 is "H", so the OR circuit is "H" regardless of the output of the temperature control device 19 of the freezer compartment.
As a result, the relay 15 is turned on, and the compressor 9 is immediately operated. At the same time, relay 17 is OFF
Then, the flow path switching valve 13 is de-energized, the flow path is switched to the rapid freezing flow path, and the auxiliary cooler 8 starts its cooling action.
On the other hand, since the b output of the rapid cooling timer 28 is "H", the output of the AND circuit 26 depends on the temperature control device 23 of the refrigerator compartment, and when the temperature of the refrigerator compartment is higher than a predetermined value, the resistance value R _TH2 of the thermistor 24 is becomes smaller,
C determined by R _TH2 and R ₄ of the temperature control device 23
The potential at the point becomes lower than the potential at point D determined by the resistors R ₅ and R ₆ , and the output of the comparator 25 becomes “L”.
Therefore, the output of the AND circuit 26 becomes "L", and from c and d in Fig. 2, the output d of the blower timer 18 becomes "L".
becomes "H", the relay 16 is in the ON state, the blower 5 is operated, and cooling is promoted by the forced ventilation action. Next, if forced ventilation causes the temperature inside the refrigerator to drop below the temperature at which food freezes (e.g. 0°C
(Below) The resistance value R _TH2 of the thermistor 24 increases and the C potential becomes higher than the D potential, so the output of the comparator 25 becomes "H", and the "H" signal is sent from the b output of the quenching timer 28 to the AND circuit 26. The output of the AND circuit 26 is always "H". Therefore, the output state of the blower timer 18 is determined from c and d in Fig. 2 when the output signal is "H" for t ₁ hour and "L" for t ₂ hours when the quick cooling timer 28 reaches time T or the quick freezing switch 27 is pressed again. Repeat until supercooled. During this time, cold air ventilation in the refrigerator compartment 7 is suppressed and rapid freezing continues to prevent overcooling, but if the temperature inside the refrigerator compartment drops abnormally (-1
℃ or less) The resistance value R _TH2 of the thermistor 24 becomes larger, the C potential of the temperature control device 29 becomes higher than the E potential, and the output of the comparator 30 becomes "H".
Although the output of the AND circuit 31 is in the process of rapid freezing, the output becomes "L" and the rapid freezing is interrupted, and the temperature control device 19 of the freezer compartment 6 performs cooling control to interrupt the rapid freezing and prevent overcooling. Prevents food from freezing.

Effects of the Invention As is clear from the above configuration, the present invention provides a quick freezing chamber equipped with a direct cooling type auxiliary cooler in the freezing chamber of a forced ventilation type refrigerator-freezer, and only main cooling is performed during normal cooling. During quick freezing, the flow path control device switches the refrigerant to flow through the main cooler and auxiliary cooler, and during quick freezing, the blower is stopped and the quick freezing is stopped due to changes in the internal temperature of the refrigerator compartment. This system is configured to control the interruption and stop of the compressor, and has the effect of suppressing the supercooling state of the refrigerator compartment caused by continuous operation of the blower each time. There is no danger that the temperature inside the refrigerator will drop and the food being stored will freeze, and if the temperature inside the refrigerator rises, the frozen food will become half-thawed, resulting in quality deterioration. In addition, by stopping the blower, overcooling is prevented without interfering with the effect of the quick freezing capacity, but when the temperature drops to a certain level, it is necessary to immediately prevent overcooling of the refrigerator compartment, so the compressor is stopped and the cooling is stopped quickly. It is possible to prevent supercooling immediately after freezing is interrupted, that is, to make the most of the effect of the rapid freezing capacity according to the supercooling state of the refrigerator compartment, and to perform optimal control over freezing and quality deterioration of food.

[Brief explanation of drawings]

FIG. 1 is a control circuit diagram of a quick freezing device for a refrigerator according to an embodiment of the present invention, FIG. 2 is an operation explanatory diagram showing the operating status of a quick cooling timer device, and FIG. 3 is a sectional view of a refrigerator showing a conventional example. FIG. 4 is a piping diagram of the refrigeration cycle. 3... Cooling room, 4... Main cooler, 5... Blower, 8... Auxiliary cooler, 6'... Rapid freezing room, 9
... Compressor, 13 ... Flow path control device, 27 ... Rapid freezing switch.

Claims (1)

[Claims] 1. A blower that circulates the air cooled by the main cooler installed in the cooling room to the freezer compartment and the refrigerator compartment, an auxiliary cooler located inside the freezer compartment, and a blower that allows the refrigerant to flow only to the main cooler or the main cooler. a flow path control device that controls whether the air flows to both the cooling chamber and the auxiliary cooler; a temperature control device that detects temperature changes in the refrigerator compartment during rapid freezing and controls the operation of the blower and the compressor of the refrigeration cycle; A quick freezing switch is provided which causes the compressor to operate continuously and causes refrigerant to flow continuously into the auxiliary cooler, and during this quick freezing, the temperature control device of the refrigerator compartment detects a predetermined temperature drop in the refrigerator compartment, and A quick freezing device for a refrigerator that stops the operation of the blower and also stops the operation of the compressor when the temperature drops to a predetermined value.