JPH0746002B2 - Ice makers such as refrigerators - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ice making device arranged in a freezer or the like of a refrigerator and capable of producing particularly transparent ice.

2. Description of the Related Art Conventionally, in a refrigerator for a garden or the like, an ice making device for accommodating an ice making plate is arranged in one part of a freezing room, and the water in the ice making plate is frozen by the cooling action of the cold air flowing through the ice making device. It is common practice to produce ice.

However, with such an ice production method, freezing of water in the ice tray during ice production proceeds from the contact surface between the ice tray and water and the contact surface between cold air and water to the central portion. As a result, gas components and impurities dissolved in water are confined in the center of the ice, resulting in cloudiness and opaque ice in the center, which is organoleptically suitable for drinks such as whiskey. It wasn't what it was.

Therefore, there has been a need for transparent ice from the past, and devices for producing it have been described, for example, in FIGS.
The method shown in the figure is considered. The contents will be described below with reference to the drawings.

Reference numeral 1 denotes a refrigerator main body, which is divided by a partition wall 2 into a freezer compartment 3 at an upper portion and a refrigerating compartment 4 at a lower portion. 5 is a cooler for the refrigeration cycle, 6 is a blower for forced ventilation, and each is the freezing chamber 3
Is located on the back of. Reference numeral 7 denotes an ice making device arranged at the bottom of the freezing chamber 3, which comprises a first ice making chamber 8 for producing transparent ice on the upper stage of the box 7a and a first ice making chamber for producing normal ice on the lower stage. Two ice making chambers 9 are provided. The outer wall of the first ice making chamber 8 excluding the bottom surface and the front surface is surrounded by a heat insulating material 10, and a heating plate 12 made of aluminum having a heater 11 arranged on the back surface is provided on the top surface and an aluminum plate is provided on the bottom surface. Cooling plates 13 made of aluminum are respectively arranged. Reference numeral 14 is an air passage formed below the cooling plate 13, and reference numerals 15 and 16 are a first ice tray and a second ice tray housed in the first ice making chamber 8 and the second ice making chamber 9, respectively. Is. Reference numeral 17 denotes a discharge duct for forcing the cool air cooled by the cooler 5 to the ice making device 7 by the blower 6, and a discharge port 18 formed at the lower end of the discharge duct 17 and the second passage 14 respectively. It communicates with the inside of the ice making chamber 9. Reference numeral 19 is a return duct for returning the cold air discharged into the freezer compartment 3 to the cooler 5, and 20 is an ice making switch for starting transparent ice making. Further, reference numeral 21 is a refrigeration cycle compressor installed in the lower rear part of the main body 1.

Next, the electric circuit will be described. The blower 6 and the compressor 21 are connected in parallel, connected in series with the relay contact 22, and then connected to the power supply. The heater 11 has a relay contact 23
Is connected in series and then connected to the power supply.

Reference numeral 24 denotes a freezer compartment temperature control device, which is provided with a temperature sensor 25 provided in the freezer compartment 3, resistors R ₁ , R ₂ , and R ₃ , a comparison circuit including a comparator 26, a transistor 27, and a relay coil 28. , The output of the comparator 26 is the transistor
Connected to 27 bases. In addition, the transistor 27
A relay coil 28 for suction that opens and closes the relay contact 22 is connected to the collector of the. Reference numeral 29 is an ice making control device, which comprises the ice making switch 20, the timer 30, and the transistor 3
1, equipped with a relay coil 32, the ice making switch 20
The output of is connected to the input of the timer 30
The output of is connected to the base of the transistor 31. To the collector of the transistor 31, a suction relay coil 32 for opening and closing the relay contact 23 is connected. Here, the timer 30 is configured to output the "H" signal continuously for a predetermined time (t _0h ) once a High signal (hereinafter referred to as "H") is input to the input.

In such a configuration, when the temperature of the freezer compartment 3 is higher than a predetermined value, the resistance value R _TH of the temperature sensor 25 is sufficiently small and the output of the comparator 26 is "H", so that the transistor 27 is turned on and the relay coil is turned on. 28 conducts. Then, the relay contact 22 is closed, the compressor 21 is operated, and the cooler 5 performs a cooling action. At the same time, the blower 6 is operated and the cool air cooled by the cooler 5 is forcibly ventilated into the freezing compartment 3 and the refrigerating compartment 4 and is also supplied to the ice making device 7 through the discharge duct 17 and the discharge port 18. When the cool air that has flowed into the ice making device 7 passes through the ventilation passage 14, it cools mainly the water surface of the second ice tray 16 that is stored in the second ice making chamber 9 to cool normal ice. The cooling plate 13 forming the lower surface of the first ice making chamber 8 is cooled and the cooling plate 13 is cooled. The cool air that has passed through the ventilation passage 14 is returned to the cooler 5 through the return duct 19 together with the cool air that has convected inside the freezer compartment 3.
After that, if the freezer compartment 3 is cooled to a predetermined temperature, the resistance value R _TH of the temperature sensor 25 increases, and the comparator 26
Generates a Low signal (hereinafter referred to as "L"). For this reason, the transistor 27 is turned off, the conduction to the relay coil 28 is cut off, the relay contact 22 is opened, and the compressor 21 and the blower 6 are stopped. Thereafter, this operation is repeated to perform a normal cooling operation, and the cooling plate 13 of the first ice making chamber 8 is sufficiently cooled and maintained. In this state, when the user stores the first ice tray 15 filled with water to make transparent ice in the first ice making chamber 8 and at the same time turns on the ice making switch 20, the "H" signal is output. Is input to the timer 30. Timer 30 at the same time
Outputs the "H" signal continuously for a predetermined time (t _0h ), the transistor 31 continues to be turned on during this time, the relay coil 32 is made conductive, the relay contact 23 is closed, and the heater 11 is energized. It Then, after (t _0h ), the output of the timer 30 becomes “L”, the transistor 31 is turned off, the conduction to the relay coil 32 is cut off, the relay contact 23 is opened, and the energization to the heater 11 is completed. This ice making process will be explained with reference to FIG.
For example, when the first ice tray 15 filled with water at 30 ° C. is stored in the first ice making chamber and the ice making switch 20 is turned on, the first ice tray is cooled by the cooling action of the cooling plate 13 which has already been cooled.
Cooling starts from the lower surface of the first plate 15, and at the same time, the heating action of the heating plate 12 starts from the upper surface of the first ice tray 15 when the heater 11 is energized. Therefore, the water is gradually cooled until it reaches 0 ° C. over a period of time (t _1h ). During this time, the compressor 21 and the blower 6 repeat the cycle of operation and stop depending on the temperature state of the temperature sensor 25 in the freezer compartment 3. Next, the water reaching 0 ° C. is gradually frozen in one direction from below to above by the cooling action from the cooling plate 13 on the lower surface so that the water surface is not frozen first by the heating action from the upper heating plate. Then, when the time (t _2h ) elapses, the maximum ice crystal formation zone of −5 of the maximum ice crystal formation zone is obtained when the gas component contained in the water is released from the water surface and contains almost no bubbles.
C. is reached and clear water is produced. Then, after a lapse of some time, when the _temperature reaches (t _0h ) from the start of ice making, the heater 11 turns on.
It is turned off, and the heating action from the heating plate 12 ends. Then, only by the cooling action from the cooling plate 13, the temperature is cooled to the vicinity of the temperature (for example, −20 ° C.) in the freezer compartment 3, and at this point, the ice making that can be used is completed. The time required to complete the ice making at -5 ° C to -20 ° C through the maximum ice crystal production zone is (t _3h ), and the total time (t _1h ) and (t _2h ) are combined. _{In h} ), ice making is completed.

Problems to be Solved by the Invention However, at the same time when the ice making switch 20 is turned on,
That is, when energization of the heater 11 is started from the start of ice making in which the first ice making tray 15 filled with water is stored, the water temperature is 0 ° C.
Since the heating action of the heater 11 is performed from the upper surface even during the so-called water state before reaching the temperature and starting to freeze,
It takes longer to reach. Also during this time the compressor
21. Since the blower 6 is operated and stopped depending on the temperature state of the temperature sensor 25 in the freezer compartment 3, the cooling plate 13 is not actively cooled at the time of the stop, and the time to reach 0 ° C. becomes longer. Next, the water passes through the maximum ice crystal formation zone and the heater
Compressor 21 and blower 6 have temperature sensor 2 even after 11 is turned off.
Depending on the state of 5, the cooling is performed to a temperature close to that of the freezer compartment 3 while operating and stopping, so that the cooling time also becomes long. Therefore, there is a problem that the total ice making time from the start of ice making to the completion of ice making becomes long.

The present invention solves the above-mentioned problems, and an object of the present invention is to shorten the ice making time until the production of transparent ice is completed.

Means for Solving the Problems In order to solve the above problems, the ice-making device such as the refrigerator of the present invention continuously operates the cooling means of the cooling plate during the first cooling period until the water is cooled to 0 ° C. The heating means such as a heater is deactivated at the same time when the water is passed through the maximum ice crystal formation zone, and the heating means is operated during the heating period during which ice is generated, and the ice-making after the ice crystal formation is completed. Also in the second cooling period until completion, the cooling means is continuously operated and the heating means is stopped similarly to the first cooling period.

Operation In the present invention, with the above-mentioned configuration, the water is rapidly cooled by continuously receiving only the cooling action from the cooling plate in the first cooling period until the temperature reaches 0 ° C. Further, even after passing through the maximum ice crystal production zone, the cooling action is continuously applied similarly to the stop of the heating means to rapidly cool the temperature to around the freezing room temperature.

Example An ice making device such as a refrigerator according to an example of the present invention will be described below with reference to FIGS. 1 to 3. It should be noted that the same components as those of the related art are designated by the same reference numerals and detailed description thereof will be omitted.

Reference numeral 33 is an ice making device provided in the lower portion of the freezer compartment 3, but the internal configuration is the same as that of the conventional example, and only the control specification is different. That is, 34 is a freezer compartment temperature control device, which is provided with a temperature sensor 25, resistors R ₁ , R ₂ , R ₃ , a comparison circuit including a comparator 26, an OR circuit 35, a transistor 27, and a relay coil 28. The output of 26 is the OR circuit 35
The output of the OR circuit 35 is connected to the transistor 27
Connected to the base of. The collector of the transistor 27 has a relay coil for suction that opens and closes the relay contact 22.
28 is connected. 36 is an ice making control device, which is an ice making switch 20, a timer 37, a transistor 31, a relay coil.
32, the output of the ice making switch 20 is connected to the input of the timer 37. Here, the timer 37 outputs the "H" signal from the a terminal for a predetermined time (t _1'h ) once the "H" signal is input, and then outputs the "H" signal to the b terminal for the predetermined time (t _0'h ). Further, the "H" signal is output, and finally the "H" signal is output from the a terminal until the set time (t ' _h ) until the completion of ice making is reached. Next, the output of the a terminal of the timer 37 is connected to the other input of the OR circuit 35 of the freezer compartment temperature control device 34, and the output of the b terminal is connected to the base of the transistor 31. A collector relay coil 32 for opening and closing the relay contact 23 is connected to the collector of the transistor 31.

In such a configuration, when the user turns on the ice making switch 20, the "H" signal is input to the input of the timer 37 and the "H" signal is output from the a terminal during (t ₁ ′ _h ).
One input of the OR circuit 35 becomes "H", and the output becomes "H" regardless of the other input. Therefore, the transistor 27 is turned on, the relay coil 28 is conducted, the relay contact 22 is closed, and the compressor 21 and the blower 6 are continuously operated. Then, the cooling plate 13 of the first ice making chamber 8 is continuously cooled by the cold air flowing through the ventilation passage 14. During this period, the output of the b terminal of the timer 37 is "L", so the transistor 31 is OFF, that is, the heater 1
1 is OFF, there is no heating action from the heating plate 12, and the water in the first ice tray 15 is rapidly cooled toward 0 ° C and reaches 0 ° C in a short time (that is, t _{1 '} < t ₁ ). Next, when (t _1'h ) elapses, the output of the timer 37 is "H" output from the terminal b for the time (t _0'h ), during which the transistor 31 is turned on and the relay coil 32 is conducted. The relay contact 23 is closed and the heater 11 is turned on. Therefore, the heating plate 12 on the upper surface of the first ice tray 15 is gradually cooled above the cooling plate 13 on the lower surface to freeze the water so that the water surface is not frozen first. Immediately before the time (t 0 ′ _h ) elapses, that is, after the terminal b is _switched (t 2 ′ _h ), gas components in the water are released from the water surface and transparent ice is generated. Then, when (t ₀ ′ _h ) further elapses, the output of the timer 37 is _switched from the b terminal to the a terminal again, and the “H” signal is output until the ice making completion time (t ′ _h ) is reached. That is, the continuous cooling action without the above-described heating action is performed, and the temperature is rapidly cooled to near the temperature of the freezer compartment 3 (about -20 ° C) in a short time. Ie 0
℃ the period up to _{t l'H} (conventional example t _1h), the transit time of the maximum ice crystal formation zone _{t 2'H} (conventional example t _2h),
The subsequent cooling period for finishing is t _3'h (t _{3h in the} conventional example)
Overall ice making time and _{t 'h = t 1'h + t} 2'h
+ T _3'h is the ice making time of the conventional example t _h = t _1h + t _2h + t _3h
It is much shorter.

EFFECTS OF THE INVENTION As described above, according to the present invention, the first cooling period until the water reaches 0 ° C. and the third cooling period after the end of the heating action of the second cooling period are without heating action and Since the continuous cooling action is performed, the required time is shortened in each period, and the effect that the total ice making time can be greatly shortened is obtained.

[Brief description of drawings]

FIG. 1 is an electric circuit diagram of an ice making device such as a refrigerator showing an embodiment of the present invention, FIG. 2 is a characteristic diagram when transparent ice is produced by the ice making device, and FIG. 3 is equipped with the ice making device. Fig. 4 is a sectional view of a refrigerator, and Fig. 4 is a sectional view of a refrigerator equipped with a conventional ice making device.
Fig. 5 is a front view of the ice making device, Fig. 6 is a sectional view of the ice making device of Fig. 5, Fig. 7 is an electric circuit diagram of the ice making device, and Fig. 8 is a view of producing transparent ice by the ice making device. FIG. 8 …… First ice making room (ice making room), 10 …… Insulation material, 11 ……
Heater (heating means), 12 ... Heating plate, 13 ... Cooling plate, 14
...... Ventilation path (cooling means), 15 ...... 1st ice tray (ice tray), 20 ... Ice switch, 33 ... Ice making device, 36 ... Ice making control device.

Claims (1)

[Claims] 1. A cooling plate, cooling means for cooling the cooling plate, an ice making chamber having the cooling plate as a bottom face and an opening in the front face, and an ice making chamber formed in the ice making chamber and placed on the cooling plate. An ice tray placed, a heating plate having a heating means provided on the upper surface of the ice tray, a heat insulating material arranged in an outer wall excluding the bottom surface and the front surface of the ice making chamber, and an ice making switch for instructing the start of ice making A first cooling period in which the heating means is stopped and the cooling means is continuously operated immediately after the ice making switch is turned on; and a second cooling period in which the heating means is operated subsequent to the first cooling period. An ice making device, such as a refrigerator, including an ice making control device having a cooling period and a third cooling period in which the heating unit is stopped and the cooling unit is continuously operated after the second cooling period.