JPH0235224B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rapid freezing device that is used in a forced draft type refrigerator-freezer, etc., and includes a direct cooling type auxiliary cooler provided in a part of a freezer compartment.

Structure of the conventional example and its problems The conventional example will be explained with reference to FIGS. 1 and 2. Reference numeral 1 denotes a main cooler 4 housed in a cooling chamber 3 constructed within a partition wall 2. This is a forced draft type refrigerator in which air cooled by the main cooler 4 is circulated by a blower 5 to a freezing chamber 6 and a refrigerating chamber 7. Reference numeral 6' denotes a quick freezing chamber which is provided with a separate direct cooling type auxiliary cooler 8 within the freezing chamber 6;
It is used to quickly freeze food.

A damper thermostat 14 is provided at the entrance of the refrigerator compartment 7 to adjust the amount of cold air inflow. As shown in Fig. 2, the refrigeration cycle consists of a normal flow path that circulates from compressor 9 to condenser 10 to first hand tube 11 to main cooler 4 to compressor 9, and from compressor 9 to condenser 10. →Second capillary tube 12→Auxiliary cooler 8→Main cooler 4→Compressor 9 A flow path control device 13 (hereinafter referred to as a switching valve 13) is provided to switch the circulating flow path for rapid freezing. Rapid freezing is performed by switching the flow path of the valve 13. During this rapid freezing, the compressor 9 is forced to operate continuously. At this time, the number of heat exchangers in the main cooler 4 is reduced, the evaporation temperature of the auxiliary cooler 8 is maintained at a low temperature, and the freezing speed of the food in contact with the auxiliary cooler 8 is increased.
The quick freezing effect is influenced by the choice of whether to stop the operation of the blower 5 during quick freezing or to operate the blower 5 and give priority to increasing the amount of heat exchange by forced convection. However, when commanding the operation or stop of the blower 5 during quick freezing, generally the quick freezing time is divided into predetermined times,
One method is to perform the switching. however,
In this case, there is no correlation with the article temperature, and as a control method, the wood grain is rough. Another method is to use a temperature detection device that indirectly detects the temperature of the article, but in this case as well, a certain temperature is set at which the blower 5 is operated and stopped, and control is performed based on this temperature. Even though the temperature of the item has reached the temperature range of the freezing process, the temperature of the temperature detection device rises due to heat loads such as opening and closing the door.
There was a drawback that a temperature correlation with the article could not be obtained and a rapid freezing effect could not be obtained.

Purpose of the Invention In view of the above-mentioned points, an object of the present invention is to most efficiently operate and stop a forced draft fan during quick freezing to increase the quick freezing effect.

Structure of the Invention In order to achieve this object, the present invention detects the freezing temperature of an article during quick freezing, calculates the temperature gradient based on this, and operates the blower before the freezing temperature range is reached, and then stops it. This prevents uneven quick freezing effects depending on the size, type, etc. of stored items.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 3, 4, 5, and 5. Incidentally, the same parts as those in the prior art are denoted by the same reference numerals, and the description thereof will be omitted.

14 is a temperature detector that detects the temperature of the freezer compartment,
A driving signal for driving the compressor 9 of the refrigerator is issued. 1
5 is a quick freezing switch that manually outputs an ON/OFF signal. Reference numeral 16 denotes a load temperature sensor which is installed in a part of the deep freezing chamber 6' and represents temperature changes of the stored articles. Reference numeral 17 denotes an operating relay for connecting the compressor 9 to a power source, and a switch 17 is provided to connect the compressor 9 to the power source in series. 18 is a relay for blower 5 operation;
is connected in series with the switch 18' and then in parallel with the compressor 9. 19 is a flow path switching valve 1
The switching valve 13 is connected in series with the switch 19' and then connected in parallel with the power supply. This switching valve 13 is a normal flow path when the coil is conductive.
The structure is such that the flow path is switched to the quick freezing flow path when the flow is out of conduction. The relay 17 is configured to close a switch 17' when the excitation coil is energized, and the relays 18 and 19 close their contacts when the excitation coil is not energized. Reference numeral 20 denotes a control circuit, which is formed from a microcomputer CFU 21, RAM 22, RCM 23, etc., and a ROM 23 stores a program that determines the next operation based on the confirmation order of operations and the state at that time. Further, the control circuit 20 includes a timer 24 for quick freezing, which determines the maximum time of quick freezing operation by the quick freezing switch 15, for example, about 90 minutes.

Next, the operation will be explained with reference to FIG.

When the power is turned on, the states of the temperature detector 14, quick freezing switch 15, and load temperature detector 16 are input as step 1 and stored in the RAM 22. Next, the status of the quick freeze switch 15 is read from the RAM 22, and the quick freeze switch 15 is
ON determines OFF as step 2. The following explanation will be based on the assumption that the power has just been turned on and has not yet cooled down. When it is determined that the quick freezing switch 15 is OFF in step 2, the RAM 22 that stores the information that the quick freezing is in progress is reset in step 3. Next, as step 4, RAM2
2, it is determined whether the temperature detector 14 has detected a temperature equal to or higher than the set temperature. At this time, if the temperature is higher than the set temperature, the relay 17 is operated and the switch 17' is turned on to operate the compressor 9 in step 5. This process from step 1 to step 5 continues, and when the refrigerator becomes cold, the temperature sensor 14 is turned on in step 4.
If the output is below the set temperature, switch 17' of relay 17 is turned OFF in step 6, and compressor 9 is turned off.
Stop and return to step 1. This operation is also repeated, and if the temperature detector 14 outputs a temperature higher than the set temperature in step 4, then step 5 is performed.
After that, the compressor 9 is operated and the process returns to step 1, whereupon such a cooling operation is repeated.

Next, when the quick freeze switch 15 is turned on, it is confirmed that the quick freeze switch was operated in step 2.
The rapid freezing state is read from the RAM 22 and stored in the RAM 22 in step 7. Further, in step 8, the quick freezing timer 24 is started, and in step 9, it is determined whether the quick freezing switch 15 or the quick freezing timer 24 indicates the end. If quick freezing is indicated, in step 10 it is determined whether it is time to start quick freezing based on the time of the quick freezing timer 24, and if it is time to start quick freezing, in step 11 the load initial temperature ( = _T1 )
is stored in the RAM 22. Then, in step 12, it is determined whether the driving timer 24 has reached, for example, 10 minutes, and if it has not, the process goes to step 13.
The relay 19 is activated and the switch 19' operates the switching valve 13. Then, in step 14, the relay 17 is operated and the switch 17' operates the compressor 9, and the process returns to step 1. and,
Proceed to steps 1, 2, 7, 8, 9, then step 10
At , the RAM 22 determines that it is not the time to start rapid freezing, and steps 12, 13, and 14 are repeated.
As this rapid freezing operation progresses, at step 12,
When it is determined that the quick freezing timer 24 has reached, for example, 10 minutes, the load temperature detector 16 causes the RAM 22 to store the load temperature (=T ₂ ) after 10 minutes have elapsed. Note that the temperature thereafter is not stored as _T2 . Then, in step 16, A=
The calculation 10T ₁ /(T ₁ −T ₂ ) is performed to calculate the time A required to reach the freezing temperature range (for example, 0° C. here) and store it in the RAM 22. Next, in step 17, press A.
If the value is less than A, the process proceeds to steps 13 and 14, the operation of the blower 5 is synchronized with the operation of the compressor 9 as before, and the process returns to step 1. Furthermore, as the quick freezing operation progresses, if the quick freezing timer 24 is equal to or higher than A in step 17, then in step 18, the switch 18' of the relay 18 is turned on to stop the blower 5, and then steps 13 and 14 are performed. Go to and return to step 1. Then, the quick freezing timer 24 is activated for a set time (for example,
90 minutes), proceed from step 9.
19, switches 17', 18', and 19' of relays 17, 18, and 19 are turned off, and the compressor 9, blower 5, and switching valve 13 are stopped. In other words, as shown in Figure 5, the temperature transition of the article during rapid freezing is as follows:
For example, the temperature T ₂ after 10 minutes from the initial temperature T ₁ (℃)
(°C), predict the time for the item to reach the freezing temperature range (for example, 0°C), and during the time A until it reaches 0°C, the blower 5 is operated to increase the amount of heat exchange by forced convection. Priority is given to time B, and since a more rapid temperature effect is required, the blower 5 is stopped, the amount of heat exchanged in the main cooler 4 is reduced, and the evaporation temperature of the auxiliary cooler 8 is maintained at a low temperature, thereby reducing the temperature of the article. A control method suitable for refrigeration is performed.

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 freezer compartment of a forced ventilation type refrigerator-freezer, and during normal cooling, only the main cooler is used. In addition, during rapid cooling, a flow path control device is installed to flow the refrigerant between the main cooler and the auxiliary cooler, and in order to further enhance the rapid freezing effect, the temperature range of the freezing process of the item is reached. Previously, the blower was operated and then stopped after reaching the freezing temperature range.The method was to detect the temperature with a load temperature detector that represents the temperature transition of the item, calculate the temperature drop gradient of the item, and predict the time it would take to reach the freezing temperature range. Since it operates and stops the blower, it is versatile for items of various shapes and masses to be rapidly frozen, and reliable control commands can be given, making it extremely effective in practical use.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a conventional refrigerator, Fig. 2 is a piping diagram of its refrigeration cycle, Fig. 3 is a block diagram showing a quick freezing device for a refrigerator according to an embodiment of the present invention, and Fig. 4 shows its operating state. The flowchart, FIG. 5, is a time-temperature characteristic diagram during freezing of the article. 3... Cooling room, 4... Main cooler, 6... Freezing room, 7... Refrigerator room, 5... Blower, 8... Auxiliary cooler, 6'... Quick freezing room, 9... Compressor , 13
...Flow path control device, 14...Temperature detector, 16...
...Load temperature detector, 20...Control circuit.

Claims (1)

[Claims] 1. A blower that circulates the air cooled by the main cooler installed in the cooling room to the freezer and refrigerator compartments, a quick-freezing room through which the air cooled by the main cooler passes through the freezer room, and a quick-freezing room inside the quick-freezing room. A direct cooling type auxiliary cooler installed, a flow path control device that controls whether the refrigerant flows only to the main cooler or both the main cooler and the auxiliary cooler, and a compressor of the refrigeration cycle are connected continuously. The auxiliary cooler is operated to perform quick freezing by continuously flowing refrigerant to the auxiliary cooler, and is equipped with a load temperature detector for sensing the temperature of the articles stored in the quick freezing chamber, A quick freezing device for a refrigerator, comprising a control circuit that detects temperature, calculates a temperature gradient before reaching the freezing temperature range, predicts the time to reach the freezing temperature range, and stops the blower after the time reaches the freezing temperature range.