JPH0128870B2 - - Google Patents

Description

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

Structure of the conventional example and its problems The conventional example is shown in FIGS. 1 and 2. 1 is insulation wall 2
The air cooled by the main cooler 4 stored in the cooling chamber 3 constructed between the
This is a forced draft refrigerator that circulates the air. Reference numeral 8 denotes a quick-freezing chamber which is provided with an auxiliary cooler 9 of a direct cooling type separately within the freezing chamber 6, and is used to quickly freeze food. A damper thermostat 10 is provided at the entrance of the refrigerator compartment 7 to adjust the amount of cooling inflow. As shown in FIG. 2, the refrigeration cycle consists of a compressor 11 → condenser 12 → first capillary tube 1.
3→main cooler 4→compressor 11 and a normal flow path circulating, and compressor 11→condenser 12→second capillary tube 1
4 → auxiliary cooler 9 → main cooler 4 → compressor 11.
), and by switching the flow path of the switching valve 15, the compressor 11 is forced to operate continuously during rapid freezing, and the refrigerant continues to flow into the auxiliary cooler 9 to maintain the auxiliary cooler 9 at an extremely low temperature. This speeds up the freezing speed of the food that comes into contact with the auxiliary cooler 9. When the door 16 is opened or closed during quick freezing, outside air enters the freezer compartment 6 and frost forms on the surface of the auxiliary cooler 9, which has reached an extremely low temperature. Not only does the thermal conductivity of the auxiliary cooler 9 decrease and the freezing speed of food slows down, but also when the door 16 is opened and closed frequently, a large amount of frost forms on the auxiliary cooler 9, causing forced ventilation by the blower 5 after normal operation is resumed. The frost in the auxiliary cooler 9 cannot be completely sublimated by the sublimation action of the cold air, and the remaining frost develops and freezes, which further reduces the thermal conductivity.

OBJECT OF THE INVENTION In view of the above-mentioned points, an object of the present invention is to prevent frost formation on the auxiliary cooler when the door is opened during rapid freezing.

Structure of the Invention In order to achieve this object, the present invention releases the flow path switching valve only while the door is open during quick freezing, and allows the refrigerant to flow only into the main cooler, thereby allowing outside air to enter the freezing chamber. This system dehumidifies the air in the main cooler and prevents frost formation on the auxiliary cooler.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. Note that the cross section and refrigerant circuit of the refrigerator are the same as in the conventional example, so in the explanation of this embodiment, reference will also be made to FIGS. 1 and 2, and the same parts as in the conventional example will be used. The detailed explanation will be omitted.

In the figure, the compressor 11 is connected to a power source via a relay 17, and the blower 5 is connected in series with a single-pole, single-throw blower control door switch 19, and then connected in parallel with the compressor 11. There is. The flow path switching valve 15 is connected in series with a flow path control relay 20 and a single-pole, single-throw door switch 18, and then connected in parallel to a power source. The flow path switching valve 15 is configured to switch to the normal flow path when the coil is not energized and to the quick freezing flow path when the coil is energized. Here, the relay 17 closes the contact when the excitation coil is energized, and the door switch 18 and the blower control door switch 19 close the contact a when the door 16 is closed and open the contact a when the door 16 is open. The road control relay 20 is configured to open its contacts when the excitation coil is de-energized.

Next, a control device for driving these relays 17 and 20 will be described. 21 is a temperature control device, which includes a thermistor 22 and a resistor installed in a part of the freezer compartment 6.
It is composed of R ₁ , R ₂ , R ₃ and a comparator 23. The output of the comparator 23 is configured to send a signal to turn on/off the relay 17 via an OR circuit 24 by a driver circuit (not shown) such as a transistor. 25 is a quick freezing switch, and 26 is a quick cooling time timer. This rapid cooling time timer 26 is activated when the rapid freezing switch 25 is turned on.
As shown in Figure 4, when a short-term High signal (hereinafter simply referred to as "H") is input to the a input, the b output is configured to output "H" for, for example, 90 minutes during rapid freezing. . And quench time timer 2
The b output of 6 sends a signal to turn ON/OFF the relay 17 and is connected to the input of the OR circuit 24.

Next, the operational status of this configuration will be explained.
Normally, when the internal temperature of the refrigerator (freezer compartment temperature) is higher than a predetermined value, the resistance value R _TH of the thermistor 22 becomes small, and the temperature at point A determined by R _TH and R ₁ of the temperature control device 21 decreases. The potential becomes higher than the potential at point B determined by resistors R ₂ and R ₃ and the comparator 23
Since the output of the OR circuit 24 becomes "H", the output of the OR circuit 24 also becomes "H", the relay 17 is turned on via a driver circuit such as a transistor (not shown), and the compressor 11 is operated. At this time, the quick freezing switch 25 is
Since it is in the OFF state, the b output of the quenching timer 26 is a LOW signal (hereinafter simply referred to as "L"), the flow path control relay 20 is OFF, and the suction coil of the flow path switching valve 15 is de-energized. The refrigerant circuit constitutes a circulation cycle of compressor 11 -> condenser 12 -> first capillary tube 13 -> main cooler 4 -> compressor 11 to perform normal cooling. When the door 16 is closed, the a contact of the blower control door switch 19 is closed and the blower 5 is operated, and when the door 16 is opened, the a contact of the blower control door switch 19 is opened and the blower 5 is stopped. After that, when the inside of the refrigerator is cooled to a certain temperature, the resistance value RTH of the thermistor 22 increases and the A _potential becomes smaller than the B potential, so the output of the comparator 23 becomes "L" and the b of the quenching timer 26 OR circuit 24 together with the “L” signal from the output
The output becomes “L”, so relay 17 turns OFF.
As a result, the compressor 11 and the blower 5 stop. 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 25 at your discretion, the quick cooling timer 2 will start.
Since the b output of 6 continues to generate an "H" signal during the quenching time T, one input of the OR circuit 24 becomes "H" regardless of the output of the temperature control device 21.
The output of the OR circuit 24 becomes "H" and the relay 1
7 is turned ON and the compressor 11 is immediately operated. At the same time, the flow path control relay 20 is turned on, the flow path switching valve 15 is energized, the flow path is switched to the quick freezing flow path, and the auxiliary cooler 9 starts cooling. On the other hand, the a contact of the door switch 18 is closed, and when the door 16 is opened during rapid freezing, the a contact of the door switch 18 is opened and the flow path switching valve 15 is de-energized, switching to the normal freezing flow path for cooling. Therefore, the outside air that has entered the freezer compartment 6 is dehumidified by the main cooler 4. Also door 16
When the door switch 18 is closed, the a contact of the door switch 18 is closed and the flow path switching valve 15 is energized.

Effects of the Invention As is clear from the above configuration, the present invention provides a quick freezing chamber in which a direct cooling type auxiliary cooler is installed in the freezer compartment of a forced ventilation type refrigerator-freezer, and only the main cooler is used during normal cooling. During rapid freezing, a flow path control device such as a flow path switching valve is used to switch the flow of refrigerant to both the main cooler and auxiliary cooler, and when the door is opened during rapid freezing, the flow path switching device is switched. This device is configured to stop the operation and operate the flow path switching device only when the door is closed, and the outside air that enters when the door is opened or closed during quick freezing will cause frost to form on the surface of the auxiliary cooler and reduce the thermal conductivity to the food. As a result, the freezing time of foods can be prevented from slowing down, and the practical effect is extremely high.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a refrigerator showing a conventional example, Fig. 2 is a piping diagram of its refrigeration cycle, Fig. 3 is a control circuit diagram showing an embodiment of the present invention, and Fig. 4 is a quenching time timer shown in Fig. 3. This is a time chart. 3...Cooling room, 4...Main cooler, 5...Blower, 8...
Rapid freezing chamber, 9... Auxiliary cooler, 11... Compressor, 1
5... Flow path control device (switching control valve), 18... Door switch, 25... Rapid freezing switch.

Claims (1)

[Claims] 1. A blower that circulates air cooled by the main cooler installed in the cooling chamber to the freezer compartment and the refrigerator compartment; A direct cooling type auxiliary cooler placed in the freezing chamber, a flow path control device that controls whether the refrigerant flows only to the main cooler or to both the main cooler and the auxiliary cooler, and refrigeration cycle compression. A quick freezing switch that performs quick freezing by continuously operating the machine and continuously flowing refrigerant to the auxiliary cooler, and a quick freezing switch that releases the operation of the flow path control device when the door is opened during quick freezing to the main cooler. A quick freezing device for a refrigerator that is equipped with a door switch that allows refrigerant to flow through the refrigerator.