JPH02122177A - Refrigerator - Google Patents

Abstract

PURPOSE:To surely produce transparent ice by a method wherein forced pre- cooling is immediately halted when ice making is started during forced pre- cooling operation, and water is rapidly cooled continuously only by a cooling plate during cooling period in which water reaches 0 deg.C. CONSTITUTION:When an ice making switch 20 is turned on by a user during defrosting operation, 'H' signal is input to a timer 43, and 'H' signal is output from 'd' output for a time period t'1, causing a transistor 30 to be turned ON and a relay contact 23 to be closed, so that a compressor 21 and a fan 6 are brought into continuous operation. During this period, the water in an ice making tray 15 is rapidly cooled without heating by a heating plate 12, and reaches 0 deg.C in a short time period. Next, when time period t'1 has elapsed, 'H' output is output from 'e' output of a timer 37 for a time period t'0 during which a transistor 36 is turned ON and a relay contact 24 is closed, so that a heater 11 is turned ON. Thereby, the heating plate 12 above the surface of water in the ice making tray 15 is heated so as not to freeze the surface first but to gradually cool and freeze the water from a cooling plate 13 on the bottom towards the surface. Then, transparent ice is made after a time period t'2 since output is changed to 'e' output.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a refrigerator that is equipped with a defrosting function that performs forced precooling and defrosting operation, and a transparent ice making function that makes it possible to produce transparent ice.

Conventional technology In recent years, refrigerators prevent temperature rises inside the refrigerator due to defrosting operation, and when the time for defrosting approaches, the compressor is driven in advance to forcibly perform cooling operation for a certain period of time to check the temperature rise. It is common practice to cool down the inside of the refrigerator and then perform a defrosting operation to prevent the temperature inside the refrigerator from rising due to defrosting.

On the other hand, in conventional home refrigerators, etc., an ice making device that stores an ice tray is placed in one section of the freezer 3 vane, and the water in the ice tray is frozen by the cooling effect of the cold air flowing through the ice making device. It is common practice to generate ice using

However, with this ice generation method, when ice is generated, the water in the ice tray progresses from the contact surface between the ice tray and the water and the contact surface between the cold air and water to the center. As a result, gaseous components and impurities dissolved in the water are trapped in the center of the ice, resulting in a cloudy center and opaque ice, which is sensually suitable for beverages such as whisky. It wasn't something I was looking for.

Therefore, the need for transparent ice has existed since the past, and the equipment for producing it is shown in Figures 4 to 6, for example.
The method shown in the figure is being considered. The contents will be explained below according to the drawings.

Reference numeral 1 denotes a refrigerator body, which is divided by a partition wall 2 into a freezing compartment 3 at the top and a refrigerating compartment 4 at the bottom. 5 is a cooler for the refrigeration cycle, and 6 is a blower for forced ventilation.
is located on the back of the.

7 is an ice making device disposed at the bottom of the freezer compartment 3;
A first ice-making compartment 8 for producing transparent ice is provided in the upper stage of the box body 7a, and a second ice-making compartment 9 for producing normal ice is provided in the lower stage. The outer wall of the first ice-making chamber 8 except for the bottom and front side is surrounded by a heat insulating material 10, and a heating plate 12 made of aluminum with a heater 11 arranged on the back side is installed on the large side. Cooling plates 13 made of aluminum are arranged respectively. Reference numeral 14 indicates a ventilation passage formed below the cooling plate 13, and reference numerals 15 and 16 indicate a first ice tray and a second ice making tray stored in the first ice making compartment 8 and the second ice making compartment 9, respectively. It's a plate. Further, 17 is a discharge duct for forcing the cold air cooled by the cooler 5 into the ice making device 7 by the blower 6, and the discharge duct 17 is connected to the ventilation passage 14 and the second air passage by means of a discharge port 18 formed at the lower end. It communicates with the inside of the ice making room 9. 1
9 is a return duct for returning cold air discharged into the freezer compartment 3 to the cooler 5, and 20 is an ice-making switch for starting making transparent ice. Also, 21 is the main body 1
This is a 5-pressure bezo compressor for the refrigeration cycle installed at the bottom rear of the refrigeration cycle.

A defrosting heater 22 is attached to the cooler 5 to remove frost from the cooler 5.

Next, the electric circuit will be explained. The blower 6 and compressor 21 are connected in parallel, connected in series with a relay contact 23, and then connected to a power source. The heater 11 is connected in series with a relay contact 24 and then connected to a power source.

The defrosting heater 22 is connected in series with a relay contact 25 and then connected to a power source.

26 is a freezing room temperature control device, and a temperature sensor 27 provided inside the freezing room 3. A comparator 28 with resistors R1, R2, and R3 is provided. 29 is a defrosting control device, the input of which is connected to the output of the comparator 28.

Further, the C output of the defrosting control device 29 is connected to the base of the transistor 3Q. Further, an absorption glue coil 31 for opening and closing the relay contact 23 is connected to the collector of the transistor 30. Moreover, the defrosting control device 2
The b output of 9 is connected to the base of transistor 32 and has 6 vanes. Further, an absorption glue v33 for opening and closing the relay contact 26 is connected to the collector of the transistor 32. Here, the defrosting control device 29 will be explained with one input, a, and b.

There are three outputs of C, and a high signal is input to the input (hereinafter “
When a signal (referred to as H11) is input, the time of "H" is integrated, and the C output is output as a "H" signal.

After that, when integrated for a certain period of time (e.g. 8 hours), regardless of the input state, the C output will be increased for a certain period of time (e.g. 30 minutes) n
After the HIT signal is high, the output will continue for a certain period of time (for example, 45
minute) Outputs a “H” signal. Also, when the HII signal is output from the C output for a certain period of time, and from the b output for a certain period of time ``H''
During signal output, an "H" signal is also output from the C output.

34 is an ice making control device, which includes the ice making switch 20 and a timer 35, and the output of the ice making switch 20 is connected to the input of the timer 350. Further, the R input of the timer 35 is connected to the C output of the defrosting control device 29. Also, the output of the timer 35 is connected to the transistor 3.
It is connected to the base of 6. An absorbing glue v37 for opening and closing the relay contact 24 is connected to the collector of the tiger 7 basic star 36. Now, to explain the timer 35, the - degree input is H"'
When a signal is input, it is configured to continuously output a "H" signal for a predetermined period of time (to). Also, "H"' is input to the R input.
When a signal is being input, even if a °H"" signal is input to the input, the timer will not count, and the output will be "H" after a low signal (hereinafter referred to as "L") is input to the R input. ′
The signal is kept high for a predetermined period of time.

In this configuration, when the temperature of the freezer compartment 3 is higher than a predetermined value, the resistance value RTH of the temperature sensor 27 becomes sufficiently small and the output of the comparator 28 becomes H'', and the a output of the defrosting control device 29 also becomes H°. It becomes ゛.

Therefore, the transistor 30 is turned on and the relay coil 31 becomes conductive. Then, the relay contact 23 closes and the compressor 21
is operated, and the cooler 5 performs a cooling action. At the same time, the blower 6 is operated to air the cold air cooled by the cooler 5 into the freezer compartment 3. In addition to forced ventilation into the refrigerator compartment 4, there is also a discharge duct 17. It is also supplied to the ice making device 7 via the discharge port 18 . When the cold air flowing into the ice making device A passes through the ventilation passage 14, it cools mainly the ice surface of the second ice tray 16 housed in the second ice making compartment 9, thereby forming normal ice. On the other hand, the cooling plate 13 forming the lower surface of the first ice making chamber 8 is cooled. The cold air that has passed through the ventilation path 14 is returned to the cooler 5 through the return duct 19 together with the cold air that has convected in the freezer compartment 3. Thereafter, when the freezer compartment 3 is cooled to a predetermined temperature, the resistance value RTH of the temperature sensor 27 becomes large and the comparator 28 generates an L'' signal.

Therefore, the a output of the defrosting control device 29 is "L°', and the transistor 30 is turned FF.
The conduction to the compressor 21. is interrupted and the relay contact 23 is opened. The blower 6 stops. Next, when the integrated time of the defrosting control device 29 reaches a certain time, the “H” signal is output from the “al”6 of the defrosting control device 29 for a certain period of time regardless of the output of the comparator 28, and the transistor 30 is turned on. The relay coil 31 becomes conductive, the relay contact 23 closes, the compressor 21°9 page blower 6 is operated, and a forced precooling action is performed to suppress the temperature rise in the freezer compartment 3 during the removal of waste.

After the forced precooling action, “H” is determined from the b output of the defrosting control device 29.
A signal is output, the transistor 32 is turned on, and the relay coil/v33 is made conductive.Then, the relay contact 26 is closed and the silk removing heater 22 is energized.

Therefore, the frost on the cooler 5 melts. Thereafter, this action is repeated to perform a normal cooling action, and the cooling plate 13 of the first ice-making compartment 8 is also kept sufficiently cooled.

In this state, when the user places the first ice tray 16 filled with water into the first ice making compartment 8 to make transparent ice and turns on the ice making switch 20 at the same time, an "H" signal is output. is input to the timer 35. At the same time, the timer 35 continues to be "H"' for a predetermined period of time (to).
In order to output a signal, the transistor 36 continues to be ON during this time, and the relay coil 37 is conductive, the relay contact 24 is closed, and the heater 11 is energized. After (to) has elapsed, the output of the timer 35 becomes L I+, the transistor 36 goes OFF, the conduction to the V- coil 37 is cut off, the phosphor contact 24 opens, and the energization to the heater 11 ends. do. To explain this ice-making process with reference to FIG. 8, for example, when the first ice-making tray 15 filled with 30°C water is stored in the first ice-making compartment and the ice-making switch 20 is turned on, the ice-making tray 15 is already cooled. Cooling starts tb from the bottom surface of the first ice tray 150 due to the cooling action of the cooling plate 13, and at the same time, the heating action of the heating plate 12 starts from the top surface of the first ice tray 15 by energizing the heater 11. Therefore, the water is slowly cooled over time (tl) until it reaches 0°C. During this time, the compressor 21,
The blower 6 repeats a cycle of operation and stop depending on the temperature status of the temperature sensor 2 in the freezer compartment 3. Then 0℃
The water that has reached the temperature is gradually frozen in one direction from the bottom to the top by the cooling action from the cooling plate 13 on the bottom, preventing the ice surface from freezing first due to the heating action from the heating plate on the top. At the lapse of (t2), the gas components contained in the water are released from the ice surface, and transparent water containing almost no air bubbles is produced. Thereafter, after some time has elapsed, when the ice-making process reaches (to), the heater 1111 is turned off and the heating action from the heating plate 12 ends.

Then, only by the cooling effect from the cooling plate 13, the ice is cooled to around the temperature in the freezer compartment 3 (for example, -20°C), and at this point, ice making that can withstand use is completed. In addition, the time required to complete ice making from -6℃ to -20℃, when freezing is completely completed, is (t3), and the total time (1) including the above-mentioned times (11) and (12) is the time needed to make ice. It is something that will be completed.

Problems to be Solved by the Invention However, when the power supply to the heater 11 is started at the same time as the ice-making switch 20 is turned on, that is, from the time when the first ice-making tray 15 filled with water is stored, the power supply to the heater 11 is started. Since the heating action of the heater 11 is performed from the upper surface even during the so-called water state until the water reaches 0° C. and starts freezing, the time until the water reaches 0° C. is longer. During this time, the compressor 21 and the blower 6 are connected to the temperature sensor 27 inside the freezer compartment 3.
Since the cooling plate 13 is operated and stopped depending on the temperature state, the cooling plate 13 is not actively cooled when the cooling plate 13 is stopped, and it takes a longer time to reach 0°C. Next, even after the heater 11 is turned off, the compressor 21. Since the blower 6 is cooled to a temperature close to that of the freezer compartment 3 while being operated and stopped depending on the state of the temperature sensor 27, the cooling time also becomes long. For this reason, there is a problem that the overall ice making time from the start to the completion of ice making becomes long, and as a result, the water reaches 0°C.
During the first cooling period, the cooling means of the cooling plate 13 is continuously operated, while at the same time the heating means of the heater 11 is stopped, and the water is rapidly cooled. Next, during the heating period during which ice is generated, the heating means is operated, and during the second cooling period after the formation of ice crystals leading to the completion of ice making, the cooling means is continuously operated and the heating means is operated in the same way as the first cooling period. One possible method is to stop the process and rapidly cool the liquid to around freezing room temperature. However, in the above-mentioned configuration, when ice making is started by turning on the ice making switch 20 during forced precooling, for example, if the water temperature is low (5°C), the water reaches 0°C and starts freezing due to forced precooling only. As a result, after the forced pre-cooling action is completed and the defrosting heater 22 is energized, it is further cooled during the first cooling period and ice freezes, resulting in a problem that transparent ice is not produced.

The present invention solves the above-mentioned problems and aims to reliably produce transparent ice.

Means for Solving the Problems In order to solve the above problems, the refrigerator of the present invention, when ice making is started with the ice making switch during forced precooling,
Immediately stop the forced precooling action, and during the first cooling period until the water is cooled to 0°C, the cooling means of the cooling plate should be operated continuously, and at the same time, the heating means such as the heater should be stopped. During the heating period during which ice is produced, the heating means is operated, and during the second cooling period leading to the completion of ice making, the cooling means is continuously operated and the heating means is stopped, as in the first cooling period. be.

Operation The present invention has the above-described configuration, so that when ice making is started by turning on the ice making switch during the forced precooling operation, the forced precooling operation is immediately stopped, the ice making operation is started, and the ice making operation is continued until the water reaches 0°C. During the first cooling period, it is rapidly cooled by continuously receiving only the cooling action from the cooling plate. Further, even after the freezing is completed, the cooling effect is continuously applied in the same manner as when the heating means is stopped, and the food is rapidly cooled to around the freezing room temperature.

EMBODIMENT A refrigerator according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 3. Incidentally, the same components as those in the prior art are given the same reference numerals, and detailed explanation thereof will be omitted.

Reference numeral 38 denotes an ice making device provided in the lower part of the freezer compartment 3, but its internal configuration is the same as that of the conventional example, and only the control specifications are different. 39 is a defrosting control device, the C output of which is connected to one input of an AND circuit 4o. Further, the output of the AND circuit 40 is connected to the R input. To explain the defrosting control device 39 here, the a, b, and C outputs have the same specifications as before, but when the H'' signal is input to the R input, the states of the a, b, and C outputs all change to II. The C output of the defrosting control device 39 is connected to one input of an OR circuit 41, and the output of the OR circuit 41 is connected to the base of the tractor 15/transistor 30. 42 is an ice making circuit. The control device is equipped with an ice-making switch 20 and a timer 43, and the output of the ice-making switch 20 is connected to the input of the timer 43, and is also connected to the other input of the AND circuit 40. Here, the timer 43 will be explained. Once the It HI+multiplying signal is input, it outputs the C output 5"H" signal for a predetermined time (t',), and then outputs the C output for a predetermined time (t'). The output outputs a ``H'' signal, and finally the set time (t') until the ice making is completed.
) is configured to output an "H°" signal again from the C output. Next, the C output of this timer 43 is connected to the other input of the OR circuit 41, and the C output is connected to the base of the transistor 36.

In this configuration, when the temperature of the freezer compartment 3 is higher than a predetermined value, the resistance value RTH of the temperature sensor 27 becomes sufficiently small and the output of the comparator 28 becomes H', and the C output of the defrosting control device 39 also becomes H. ``'', and the output of the OR circuit 41 also becomes °H''. Therefore, transistor 30 turns on and relay coil 31 becomes conductive. Then, the relay contact 23 is closed, and the compressor 21 and the blower 6 are operated to perform a cooling action. Thereafter, when the freezer compartment 3 is cooled to a predetermined temperature, the resistance value RTH of the temperature sensor 27 increases and the comparator 2
8 becomes L'', and the C output of the defrosting control device 39 also becomes L.
Also, the dll power of timer 43 is also due to "L"'.
The output of the OR circuit 41 also becomes °L°'.

Therefore, the transistor 31 is turned off and the relay coil /L/
31 is cut off, relay contact 23 opens, and compressor 21. The blower 6 stops. Next, when the cumulative time of the defrost control device 39 reaches a certain time, the "H'" signal is output for a certain period of time from the C output of the defrost control device 39, regardless of the output of the comparator 28, the transistor 3o is turned on, and the compressor 2
1. The blower 6 is operated to perform forced precooling of the freezer compartment 3. After that, from the defrosting control device 390b output “H
"The signal is output, the transistor 32 turns on, and the relay coil 33 becomes conductive.Then, the relay contact 25 closes, the defrost heater 22 is energized, and the frost attached to the cooler 5 melts.Next, When the user turns on the ice-making switch 2o, a ``H'' signal is input to the input of the timer 43 and a ``H'' signal is output from the C output during (t'1). One input becomes H', and the output becomes °l Hl'' regardless of the other input. Therefore, the transistor 30 is turned on, and the transistor v31 becomes conductive, the relay contact 23 is closed, and the compressor 21 is turned on. and the blower 6 are operated continuously.Then, the cooling plate 13 of the first ice-making compartment 8 is continuously cooled by the cold air flowing through the ventilation path 14. Also, during this time, the C output of the timer 43 is L°'. The transistor 36 is OFF, that is, the heater 11 is OFF, and there is no heating effect from the heating plate 12, and the first ice tray 1
The water inside 5 is rapidly cooled towards 0℃ and reaches 0℃ in a short time.
(i.e., t', <tl).

Next, when (t'1) elapses, the output of the timer 37 is ``H'' changing force from the C output for the time (t'.), and during this time, the transistor 36 is turned on and conducts to the relay coil 37. Relay contact 24 is closed and heater 11 is turned on. At this point, the heating plate 12 on the top page 18 of the first ice tray 15 is heated and the water is gradually cooled upward from the cooling plate 13 on the bottom surface so that the water surface does not freeze first. Then, just before time (t'q) passes, that is, C
After the output is switched (t'2), the gaseous components in the water are released from the ice surface and transparent ice is produced. And furthermore (tl
When o) has elapsed, the output of the timer 43 switches from the C output to the C output again and outputs the ``H'' signal until the ice making completion time (t) is reached.

That is, the continuous cooling action without the above-mentioned heating action is performed, and the refrigerator is rapidly cooled to about the temperature of the freezer compartment 3 (approximately -2C) in a short time. In addition, the cumulative time of the defrosting control device 39 is a fixed time, and the ice making switch 20 is activated during forced precooling.
When ice making is started by turning on the signal, the C output of the defrosting control device 39 outputs the fi ``H'' signal, and the output of the ice making switch 2o also becomes H°, and the output of the AND circuit 40 also becomes H°.
' is input to the R (reset) input of the defrosting control device 39, the defrosting control device 39 is reset, the forced precooling action is stopped, and the ice making action is started. That is, during transparent ice making, the period until the temperature reaches 0°C is t'1 (11 in the conventional example), the freezing 19 vane time is t'2 (t2 in the conventional example), and the final cooling period after that is t'3 (11 in the conventional example). If the conventional example is t3), the total ice making time t'-7'1+t'2+t'3 is the ice making time t of the conventional example.
= t1 + t2 + t3, and if ice making is started during forced pre-cooling, stop forced pre-cooling,
The forced precooling time (for example, 30 minutes) + t'1 hour prevents the water from reaching 0°C and starting to freeze, and ultimately prevents clear ice from being formed. ice is generated.

Effect of the invention As described above, according to the present invention, the following effects can be obtained.

(1) The first cooling period until the water reaches 0°C, and the third cooling period after the heating action of the second cooling period ends, because there is no heating action and continuous cooling action is applied. The required time is shortened during this period, and the overall ice making time can be greatly shortened.

(2) If ice making is started during the forced precooling action, the forced precooling action is immediately stopped, and the water reaches 0°C during the first cooling period of the ice making action, and the forced precooling action and the first This prevents the cooling period from becoming cloudy due to an unnecessarily long cooling period, and allows stable and transparent ice to be produced.

[Brief explanation of drawings]

FIG. 1 is an electric circuit diagram of a refrigerator showing an embodiment of the present invention;
Fig. 2 is a characteristic diagram of the same refrigerator when producing transparent ice, Fig. 3 is a cross-sectional view of the same refrigerator, Fig. 4 is a cross-sectional view of a conventional refrigerator, Fig. 5 is an electric circuit diagram of the same refrigerator, FIG. 6 is a characteristic diagram of the same refrigerator when producing transparent ice. 1... Refrigerator, 3... Freezer, 4...
... Refrigerator room, 5 ... Cooler, 8 ...
1st ice making room (ice making room), 1o...Insulation material, 11
... Heater, 12 ... Heating plate, 13 ...
...Cooling plate, 16...First ice tray (ice tray)
, 2o... Ice making switch, 21... Compressor, 22... Defrosting heater, 26... Freezer room temperature control device, 39... Defrosting control device, 42・
...Ice making control device. Name of agent Patent attorney Shigetaka Awano and one other person Ice-making room (ice-making supervisor) Stimulating heat material heater l:r 1st ice-making tray (ice-making tray) Ice-making switch pressure J ＾゛? ?

Claims (1)

[Claims] A freezer compartment, a refrigerator compartment, a freezer compartment temperature control device that detects the temperature in the freezer compartment and controls the operation of the compressor of the refrigeration cycle, and integrates the operating time of the compressor and controls the temperature for a certain period of time after the completion of the integration. A defrosting control device that causes a compressor to perform a forced pre-cooling operation and then energizes a defrosting heater that melts frost in a cooler of a refrigeration cycle; a cooling plate installed in the freezing chamber; and a cooling plate that is a bottom surface and an open front surface. An ice making room divided into sections,
an ice making tray stored in the ice making chamber and placed on the cooling plate; a heating plate equipped with a heater provided on the top surface of the ice making tray; and heat insulation disposed within the outer wall of the ice making chamber excluding the bottom and front surfaces. an ice-making switch that commands the start of ice-making; a first cooling period in which the heater is stopped immediately after the ice-making switch is turned on and the compressor is continuously operated;
a second cooling period in which the heater is operated following the cooling period; and a third cooling period in which the heater is stopped and the compressor is continuously operated following the second cooling period. means for immediately stopping the forced pre-cooling operation and performing ice-making control when the ice-making switch is turned on to enter ice-making control during the forced pre-cooling operation of the compressor before defrosting; Refrigerator with.