JPH01181066A - Ice making device for refrigerator and the like - Google Patents

Abstract

PURPOSE:To prevent frosting on the upper surface of an ice making pan and permit the production of transparent ice stably even when a change is generated in a thermal load condition upon making the transparent ice, by a method wherein an ice making device is provided with a first heater, conducted only when the transparent ice is being made and a cooling means is operated, and a second heater, conducted at all times when the cooling means is not being operated. CONSTITUTION:A heater 11 is connected in series to an ice making switch 20 and is connected in parallel to a compressor 22 and a fan 6 while the heater 11 is connected to an electric power source through a thermostat 21. A second heater 24 is connected in series to the OFF- contact of the thermostat 21 and the capacity of the second heater is set at a small capacity about 1/5 of the same of the first heater. The second heater 24 is conducted at all times when the thermostat 21 is being put OFF in spite of the ON/OFF of the ice making switch 20 whereby a heating plate 12 is heated slightly and frosting will never be generated on the heating plate 12 during ice making. The first heater 11 is conducted in synchronism with the cooling means during making the transparent ice, therefore, is balanced with heating and ice making may be advanced from the lower surface to the upper surface of an ice with a predetermined freezing speed even when a change is generated in an atmospheric temperature or a load condition.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an ice-making device that is disposed in a freezer compartment of a refrigerator and is particularly capable of producing transparent ice.

Conventional technology Conventionally, in home refrigerators, etc., an ice making device that stores an ice tray is placed in one section of the freezing chamber, and the water in the ice tray is frozen by the cooling effect of cold air flowing through the ice making device. It is common practice to generate ice by

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 not suitable for drinks such as whisky. It was not suitable for.

Therefore, there has been a need for transparent ice since 1999, and the equipment for producing it is shown in Figures 5 to 9, 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 placed at the bottom of the freezer compartment 3;
A first ice-making compartment 8 for producing transparent ice is provided in the upper stage, and a second ice-making compartment 9 for producing regular ice is provided in the lower stage. The first ice-making chamber 8 is surrounded by a heat insulating material 1o on the outer wall except for the bottom and front surface, and there is an aluminum heating plate 12 on the top surface with a heater 11 disposed on the back surface, and an aluminum heating plate 12 on the bottom surface. Cooling plates 13 made of aluminum are respectively arranged. 14 is a ventilation passage formed in the upper part of the second ice making chamber 9; 15.
16 are the first ice making compartments 8. They are a first ice tray and a second ice tray that are housed in the second ice tray 9. Also, 17
￥'i A discharge duct for forcing cold air cooled by the cooler 5 to the ice making device 7 by the blower 6,
Each of the ventilation passages 14 is provided with a discharge port 18 formed at the lower end.
and communicates with the inside of the second ice making chamber 9. Reference numeral 19 denotes a return duct for returning cold air discharged into the freezer compartment 3 to the cooler 6. Further, reference numeral 20 is a transparent ice-making switch, which is configured so that once the switch is turned on, the heater 11 is energized for a predetermined time (th). A thermostat 21 is provided in the freezing chamber 3 and controls the operation and stopping of the blower 6 and the compressor 22 of the refrigeration cycle.

Next, the electric circuit will be explained. After the blower 6 and the compressor 22 are connected in parallel, they are connected to a power source via the thermostat 21. After the heater 11 is connected in series with the ice making switch 20,
Connected to power supply.

In this configuration, when the thermostat 21 is turned on, the compressor 22 and the blower 6 are operated, and the air cooled by the cooler 6 is supplied to the freezer compartment 3 and the refrigerator compartment 4 by the ventilation action of the blower 6, and at the same time, the air is supplied to the discharge duct 17. The ice is discharged into the second ice-making chamber 9 and the ventilation passage 14 in the ice-making device 7 through the discharge port 18 of the ice-making device 7 .

The cold air guided into the second ice-making compartment 9 directly cools the second ice-making tray 16, and the water inside is sequentially removed from the water surface and the surface of the remaining ice tray that comes into contact with the second ice-making tray 1e. Freezes to produce regular ice. However, as mentioned above, the ice produced in this way is cloudy and does not become transparent. On the other hand, the cold air guided into the ventilation passage 14 cools the cooling plate 13. Therefore, in order to make transparent ice, the user stores the first ice tray 15 filled with water in the first ice making compartment 8 and turns on the ice making switch 2o. 11 starts the heating action via the heating plate 12, and from the bottom surface, the cooling plate 1 is heated by the cold air flowing through the ventilation passage 14.
3, the cooling or freezing action begins. Also the first
Since the outer wall of the ice tray 15 except the lower surface is covered with a heat insulating material 10, it is not affected by the cooling effect from the freezer compartment 3, and the freezing action progresses in one direction from the lower surface to the upper surface. This freezing effect is indirect cooling via the cooling plate 13, and in addition, a heating effect is added by the heater 11, which is set to an appropriate capacity in advance. The slower the freezing speed, the less air bubbles are incorporated into the ice, and ice making progresses. In this way, the freezing rate is approximately 3 tan/
If the temperature is controlled to below h, the gaseous components in the water will be degassed to the outside air from the surface of the ice that finally freezes, so the ice that is finally formed will be almost transparent and will not contain air bubbles. You will get it. Looking at this ice-making process in FIG. 9, for example, when the outside temperature is 30°C, the heater 11 is continuously energized at the same time as ice-making starts, that is, the ice-making switch 2o is turned on, and the temperature passes approximately -5°C, when freezing is completely completed. The power supply is automatically stopped after th, which is a while later.

Problems to be Solved by the Invention However, such a configuration has the following disadvantages.

(1) If the user does not put the first ice tray 15 into the second ice tray 8, the aluminum plate 12 will not be heated and the temperature will rise to -5°C.
The temperature will be about 100%. Therefore, the water vapor that evaporates during ice making adheres to the heating plate 12 and turns into ice, and the first ice tray 16 gets stuck in the ice and cannot be removed.

(2) In this way, the heater 11 is continuously energized, and the compressor 22. Regardless of whether the blower 6 is running or stopping, the heating plate 12
As shown in Figure 8, when a constant amount of heating is applied from
When the temperature is 0°C, the amount of heat load on the refrigerator body 1 decreases, the operating time of the compressor 22 and the blower 6 decreases, and the amount of cooling of the cooling plate 13 decreases, resulting in an imbalance with the amount of heating of the heating plate 12. . In other words, the amount of heating increases relatively, making the progress of ice making slower than necessary. For this reason, if the power supply to the heater 11 is stopped, even after time t has elapsed, ice making has not yet been completed, and if the power supply to the heater 11 is stopped while the water remains, the relative cooling amount will suddenly exceed and the ice will be iced. There was a problem in that ice formed near the surface became cloudy and did not become transparent.

In addition, in order to avoid this, if the energization time t of the heater 11 by the ice making switch 20 is set long enough in advance with sufficient margin, the problem of cloudy ice being formed at low outside temperatures can be solved, but The inconvenience that the end time becomes longer than necessary cannot be resolved. In this way, according to the above example, if there is a change in the heat load conditions on the refrigerator body 1, such as the outside temperature, opening/closing the door, or loading food, it is not possible to respond each time, and depending on one condition, it may become unclear. Ice could form.

The present invention solves the above-mentioned problem, and prevents frost from forming on the top surface of the ice tray when ice is made without the ice making switch being pressed, and changes the thermal load conditions of the refrigerator body when making clear ice. The purpose of the present invention is to provide an ice making device that can stably produce transparent ice even when

Means for Solving the Problems In order to solve the above problems, an ice making apparatus such as a refrigerator according to the present invention includes a first heater that is energized only when transparent ice is being made and the cooling means is in operation, and a first heater that is energized only when the cooling means is operating. A second heater is provided which is energized when the means is not operating.

Effects of the present invention Due to the above structure, the second heater is always energized regardless of whether transparent ice is being made or not, so there is no possibility of frost forming on the heating plate above the ice making tray. In addition, during transparent ice making, the first heater is energized in synchronization with the cooling means, so cooling and heating are balanced, and even if the outside temperature or load conditions change, ice making progresses from the bottom surface to the top surface at a predetermined freezing speed. do.

Embodiment Hereinafter, an ice making apparatus such as a refrigerator according to an embodiment of the present invention will be explained with reference to FIGS. 1 to 4. It should be noted that the same components as those in the prior art are given the same reference numerals, and detailed explanation thereof will be omitted.

23 is an ice making device, which is installed in the lower part of the freezer compartment 3. Further, in the electrical circuit diagram of FIG. 1, the heater 11 is connected in series with the ice-making switch 20, connected in parallel with the compressor 22 and the blower 6, and then connected to the power source via the thermostat 21. The second heater 24 is connected in series to the OFF contact of the thermostat 21. Also the first
The heater 11 and the second heater 24 are arranged on the same plane of the heating plate 12, and the second heater is set to have a small heater capacity about μ of the first heater.

In such a configuration, the second heater 24 is connected to the ice making switch 2.
Thermostat 21 always on regardless of 0N10FF
When the ice-making switch 2o is turned off, the power is on, and even if ice is made without pressing the ice-making switch 2o, the heating plate 12 is slightly heated, and frost does not form on the heating plate 12 during ice-making, making it impossible to remove the ice-making tray. There is no.

Also, to explain the ice making process with reference to FIG. 2, when the ice making switch 2o is turned on, the heater 11 is also energized in synchronization with the operation of the compressor 22 and the blower 6, and when the compressor 22 and the blower 6 are stopped, the heater 11 is turned on. The power supply will also be stopped.

That is, when the thermostat 21 is turned on, the compressor 22 and the blower 6 are operated, and the cold air cooled by the cooler 5 is sent to the duct 17. The cooling plate 13 is cooled while flowing into the ice making device 23 through the discharge port 18 and passing through the ventilation path 14 . Then, freezing progresses from the bottom surface of the first ice tray 16. - direction,
At the same time, the heating plate 12 is heated by the heater 11, and the first
Cooling and heating are balanced so that the top surface of the ice cube tray 16 does not freeze first. And thermostat 21 is off
If F is selected, the compressor 22 and the blower 6 are stopped, and the cooling power to the cooling plate 13 is rapidly reduced without allowing cold air to flow through the ventilation path 14.

At the same time, the heating plate 1 also stops energizing the heater 11.
Since the heating effect caused by 2 is also eliminated, a part of the ice that is in the process of freezing does not melt again, and the ice making time does not become longer than necessary. That is, a condition in which the thermostat 21 is turned off for a long time;
For example, even when the outside temperature is low, the amount of heating decreases as the amount of cooling decreases, so the amount of cooling and the amount of heating are always balanced, and the time required to complete ice making becomes almost constant. In other words, the second
In the illustrated example, the outside air temperature is 30° C. and 10° C., but under both conditions, ice making is completed within the time set by the ice making switch 2o, and transparent ice is obtained. Further, when the outside temperature is low, such as 6° C. or lower, the thermostat 21 is turned off for a long time of one hour or more, and the first heater 11 is not energized for a long time, so there is a risk that the surface of the heater 11 may freeze. But the second
Since the heater is energized when the thermostat 21 is OFF, this does not occur and transparent ice can be obtained stably over a wide range of outside temperatures from 36°C to around 0°C. Furthermore, conditions in which the heat load conditions on the refrigerator body 1 change other than changes in outside air temperature, such as opening/closing the door in actual use or adding a food load, increase the ON time of the thermostat 29 and reduce the cooling amount of the cooling plate. When the amount of heat increases, the segmented heat amount also increases in synchronization to maintain a balance, and the time required for ice making is controlled to be constant, resulting in transparent ice.

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

(1) Regardless of the 0N10FF setting of the ice-making switch, the second heater is always energized when the means for cooling the cooling plate is not operating, so even if ice is made without the ice-making switch being pressed, there is no ice on the heating plate. There is no stickiness and there is no inconvenience of not being able to take the ice cube tray in and out.

(2) Since the first heater is energized in synchronization with the cooling means, the balance between cooling and heating can be maintained even if the cooling conditions change due to changes in outside air temperature, changes in heat load due to opening and closing of the door, and changes in the heat load due to the insertion of food. The time required for dripping and ice making is constant, and transparent ice can be obtained stably under the actual operating conditions of the refrigerator.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram of a refrigerator showing an embodiment of the present invention;
Figure 2 shows the ice making characteristics of the ice making device installed in the refrigerator.
3 is an enlarged sectional view of the ice making device, FIG. 4 is a sectional view of the refrigerator, FIG. 5 is a sectional view of a conventional refrigerator, and FIG. 6 is an enlarged front view of the ice making device shown in FIG. Figure 7 is an enlarged sectional view of the ice making device shown in Figure 6, Figure 8 is an electric circuit diagram of the refrigerator shown in Figure 6, and Figure 9 is an ice making characteristic diagram when ice is made with the ice making device of the refrigerator shown in Figure 5. be. 8...First ice making room (ice making room), 1o...
...Insulation material, 11...First heater, 12...
...Heating plate, 13...Cooling plate, 14...
... Ventilation path (cooling means), 16... First ice tray (ice tray), 23... Ice making device, 24...
...Second heater. Name of agent: Patent attorney Toshio Nakao and 1 other person77
-+7 peak meter - Throat part of spear 2 Figure 1 Figure 2 Figure 8-''-OI ice making! (Ice making room) IQ-# I/A material++-:?1 and part I2- Heating release 23 - Incoming device 24 - Oni heater Fig. 3 8 - 1st 1: Chamber (ice making room) 12 - tta m handling Fig. 5 Fig. 6 ＼ Fig. 7

Claims (1)

[Claims] a cooling plate; a cooling means for cooling the cooling plate; an ice-making chamber partitioned with the cooling plate as a bottom and an open front; and an ice-making tray housed in the ice-making chamber and on which the cooling plate is placed. , a heating device comprising a first heater provided on the top surface of the ice tray and energized only when ice is being made and the cooling means is operating, and a second heater energized when the cooling means is not operating. An ice making device such as a refrigerator comprising a plate and a heat insulating material placed inside the outer wall of the ice making chamber except for the bottom and front side.