JPH01123968A - Ice machine for refrigerator, etc. - Google Patents

Abstract

PURPOSE: To make transparent ice stably by making a vent at a part of a heating plate on the upper surface of an ice making room arranged with a heater, disposing a temperature sensor in rear space of the heating plate and providing a door at the front opening of the ice making room thereby eliminating the effect of the atmosphere on the outside of the ice making room. CONSTITUTION: Atmospheric temperature in ice making room susceptible to the water temperature in an ice making pan 15 is detected by a temperature sensor 28 through a vent 26 made in a heating plate 2-7. Current conduction of a heater 25 is delayed behind start of ice making by a time required for the temperature sensor to reach a predetermined temperature corresponding to start of freezing, for example. Consequently, cooling is performed without heating until the water reaches about 0 deg.C. On the other hand, a door 29 provided at the front opening of an ice making room blocks influence of the outer atmosphere onto the inside of the ice making room. Consequently, transparent ice can be made under stabilized conditions insusceptible to the outer atmosphere and power consumption can be reduced because the efficiency of a heater is enhanced.

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 2 Previously, in a household refrigerator, an ice making device that stores an ice tray is arranged in one section of the freezing chamber, and the ice making device is heated by the cooling effect of the cold air flowing through the ice making device. It is common practice to freeze water to produce ice.

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 opaque ice with a cloudy center, making it sensually suitable for beverages such as whisky. It wasn't something I was looking for.

Therefore, there has been a need for transparent ice since the past, and a method as shown in FIG. 6, for example, has been considered for an apparatus for producing it. The contents will be explained below according to the drawings.

1 is a refrigerator main body, and a freezer compartment 3. The lower part is divided into a refrigerator compartment 4. Reference numeral 6 indicates a cooler for the refrigeration cycle, and 6 indicates a blower for forced ventilation, which are arranged on the back side of the freezer compartment 3, respectively.

7 is an ice making device placed at the bottom of the freezer compartment 3;
A first ice-making compartment 8 for producing clear 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 compartment 8 has an outer wall surrounded by a heat insulating material 10 except for the bottom and front, and an aluminum heating plate 12 with a heater 11 on the back is installed on the top, and an aluminum heating plate 12 is installed on the bottom. Aluminum cooling plates 13 are respectively arranged. 14 is a ventilation passage formed in the upper part of the second ice making compartment 9, and 16°16 is a ventilation passage formed in the upper part of the first ice making compartment 8. They are a first ice tray and a second ice tray that are housed in the second ice tray 9. Also, 17
is a discharge duct for forcing the cold air cooled by the cooler 6 into the ice making device 7 by the blower 6, and the air passage 14 and the second It communicates with the ice making room e. 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 denotes a transparent ice making switch, which is configured so that once the switch is turned on, the heater 11 is energized for a predetermined period of time.

In this configuration, the cold air cooled by the cooler 6 is supplied to the freezer compartment 3 and the refrigerator compartment 4 by the forced ventilation action of the blower 6, and at the same time is supplied to the second ice making device 7 through the discharge port 18 of the discharge duct 17. It is discharged into the ice making compartment 9 and the ventilation passage 14. The cold air guided into the second ice making compartment 9 is then
The second ice tray 16 is directly cooled, and the water inside is frozen sequentially from the water surface and the remaining surface that contacts the second ice tray 16 to produce normal ice. However, as mentioned above, the ice produced in this way is cloudy and does not become transparent. On the i side, 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 20. 11 starts a heating action via a heating plate 12, and a cooling or freezing action starts from the lower surface via a cooling plate 13. In addition, since the outer wall of the first ice tray 16 except for the lower surface is covered with a heat insulating material 10, it is not affected by the cooling effect from the vanes 3 of the freezer compartment 5, and the freezing action progresses in one direction from the lower surface to the upper surface. . This freezing effect is caused by the cooling plate 13
In addition to indirect cooling via the heater 11, which has a predetermined capacity, the heating effect is added, so the rate at which the ice grows and freezes is slower than the diffusion rate of the gaseous components in the water. Ice making progresses without air bubbles being incorporated into the ice.

If the freezing rate is controlled to approximately 3 tan/h or less in this way, the gas components in the water will be degassed from the surface of the frozen ice to the outside air, so that the ice that is finally formed will contain air bubbles. Clear ice with almost no ice content is obtained. Also, heater 1
No. 1 allows some margin in the time required to complete ice making, and automatically stops energizing after a predetermined time has elapsed.

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 21 is turned on, that is, when the first ice-making tray 15 filled with water is stored, During the so-called water state in which the water in the ice tray 15 reaches 0°C and starts freezing, the heating action of the heater 11 is performed from the top of the palm, so the temperature reaches 0°C.
It took a long time to reach this point, and as a result it took a long time to complete the ice making. Alternatively, freezing begins with a very slow cooling effect, so sometimes even when the temperature reaches 0°C, freezing does not begin and the water remains in the water state.
If a so-called supercooling phenomenon occurs, in which the ice is supercooled to below ℃, and if this condition continues for a long time and there is a delay in returning to the normal freezing state, air bubbles may disperse and form sealed opaque ice. there were. On the other hand, since the front of the first ice-making compartment 8 is open to the freezing compartment 3, the cold air in the freezing compartment 3 acts as a cooling effect on the front part of the stored first ice-making tray 16. Alternatively, there is also the problem that the freezing conditions for producing transparent ice are unstable, such as being affected by outside heat intrusion due to the opening and closing of the door of the freezer compartment 3, resulting in poor transparency.

The present invention solves the above-mentioned problems.It prevents unnecessary extension of ice-making time and opacity of ice due to supercooling phenomenon, and also eliminates the influence of the atmosphere outside the ice-making chamber to produce stable and transparent ice. The purpose of the present invention is to provide a 7H7 water device capable of producing 7H7 water.

Means for Solving the Problems In order to solve the above problems, an ice making device such as a refrigerator according to the present invention has a ventilation hole formed in a part of the heating plate on the top surface of the ice making chamber in which a heating device such as a heater is disposed. A temperature sensor for controlling the heating device is provided in a space on the back side of the heating plate facing the ventilation hole, and a door body that can be opened and closed is provided at the front opening of the ice making compartment.

Function According to the above-described configuration, the temperature sensor detects the atmospheric temperature inside the ice-making chamber, which is affected by the water temperature in the ice-making tray, through the ventilation hole provided in the heating plate. Then, for example, the start of energization of the heating device is delayed from the start of ice making until the temperature sensor reaches a predetermined temperature in response to the start of freezing of water. Therefore, cooling is performed without heating until the water reaches approximately 0°C. On the other hand, a door provided at the front opening of the ice-making chamber blocks the influence of external atmosphere into the ice-making chamber.

EXAMPLE Hereinafter, an ice making apparatus such as a refrigerator according to an example of the present invention will be described with reference to FIGS. 1 to 6. Note that, conventionally, the same components are given the same reference numerals, and detailed explanation thereof will be omitted.

21 is an ice making device box body 21 provided at the bottom of the freezer compartment 3.
The first one is framed by a and produces transparent ice in the upper layer.
ice making compartment 22, and a second ice making compartment 22 in the lower stage for producing regular ice.
An ice making room 23 is provided.

The first ice-making compartment 22 has an outer wall surrounded by a heat insulating material 24 except for the bottom and front surface, and a heater 26 is provided on the back side of the top surface, and a ventilation hole 26 is provided in a section near the center. An aluminum heating plate 27 is arranged. 28
A temperature sensor is provided on the back side of the heating plate 27 in a space formed by cutting out a part of the heat insulating plate 24 and facing the ventilation hole 26, and controls the energization of the heater 25. 29 is a door provided in the front opening of the first ice making compartment 22 so as to be openable and closable; 30 is a transparent ice making switch;
31 is a temperature A-7 group sensor for controlling the temperature of the freezer compartment 3. Further, 32 is a compressor of a refrigeration cycle provided at the rear of the lower part of the main body 1.

Next, the electric circuit and control circuit will be explained.

The compressor 32 is connected in parallel with the blower 6 and then connected to a power source via a relay contact 33.

Further, the heater 25 is connected in series with the relay contact 34 and then connected to the electrode. Next, 35 is a freezer compartment temperature control device, a temperature sensor 31° resistors R1, R2,
R3, comparison circuit with comparator 36, transistor 37. A relay coil 38 is provided, and the output of the comparator 36 is connected to the base of a transistor 37. Further, a suction relay coil 38 for opening and closing the relay contact 33 is connected to the collector of the transistor 37. 39 is an ice making control device, and a temperature sensor 28. A comparison circuit including resistors R4, R6, R6, a comparator 4o, and an ice-making switch 30. Timer 41.42.
AND circuit 43, transistor 44, relay coil 4
6, the output of the comparator 4o is AND
The output of the ice making switch 3o is connected to the input of the timer 41, and the output of the timer 41 is connected to the other input of the AND circuit 43. Here, once the timer 41 is inputted, it runs for a predetermined time t. It is configured to output a High signal (hereinafter referred to as "H") after h elapses.

Next, the output of the AND circuit 43 is connected to the input of the timer 42 and at the same time to the reset terminal of the timer 41. Here, the timer 42 is configured to continue outputting an H'' signal until a predetermined time th has elapsed once the input is applied.The output of the timer 42 is connected to the base of a transistor 44. A suction relay coil 46 for opening and closing the relay contact 34 is connected to the collector of the transistor 44.

In this configuration, when the temperature of the freezer compartment 3 is higher than a predetermined value, the resistance value RTH1 of the temperature sensor 31 becomes small and the output of the comparator 36 becomes H'', so the transistor 37 is turned on and the relay coil 38 is turned on. Then, the relay contact 11 base 7 33 is closed, the compressor 32 is operated, and the cooler 5 performs the cooling action.At the same time, the blower 6 is operated, and the cooler 5 cools the compressor 32. The cold air is forced into the freezer compartment 3° and the refrigerator compartment 4, and is also supplied to the ice making device 21 through the discharge duct 17° and the discharge port 18.

When the cold air that has flowed into the ice making device 21 passes through the ventilation path 14, it is cooled mainly from the water surface of the second ice tray 16 installed in the second ice making compartment 23, and the cold air is cooled down to form normal ice. On the other hand, the cooling plate 13 forming the lower surface of the first ice making chamber 22 is cooled. The cold air that has passed through the ventilation path 14 is returned to the cooler 6 through the return duct 19 together with the cold air that has convected in the freezer compartment s. Thereafter, when the freezer compartment 3 is cooled to a predetermined temperature, the resistance value RTH1 of the temperature sensor 31 becomes large.
6 generates a low signal (hereinafter referred to as "L"). Therefore, the transistor 37 is turned off and the relay coil 38
The conduction to the compressor 32. is interrupted and the relay contact 33 is opened. The blower 6 stops. Thereafter, this action is repeated to perform the normal cooling action, and the cooling plate 13 of the first ice making compartment 22 is also kept sufficiently cooled. In this state, when the user tries to make transparent ice and puts the first ice tray 16 filled with water into the first ice making compartment 22 and turns on the ice making switch 30 at the same time, an H'' signal is output and the timer 4
1 is input. The subsequent operation will be explained using the characteristic diagram of FIG. 6. When the "H" signal is input to the timer 41, the predetermined time t elapses. The H” signal is output with a delay of h and the AN
One input of the D circuit 43 becomes "H". At this point, the water filled in the first ice tray 15 is being cooled down to 0°C by the cooling action of the cooling plate 13. 30° C.), the atmospheric temperature inside the first ice making chamber 22 rises, and the temperature of the temperature sensor 28 also draws a rapid temperature rise curve through the ventilation holes of the heating plate 270 provided on the top surface. However, this rising curve reaches its peak within a short period of time, and thereafter changes to a temperature decreasing curve as the water temperature falls. Delay time t of timer 41. h is set so that the temperature characteristic of the temperature sensor 28 changes to the descending curve 13A, -.Thereafter, as the water temperature falls, the temperature sensor 28 is also cooled, resulting in a resistance value R,I).
I2 increases. When the temperature of the temperature sensor 28 reaches a predetermined temperature T°C corresponding to the water temperature reaching 0°C, the output of the converter 7 becomes H", and the other input of the AND circuit 43 At this point, the output of the AND circuit 43 becomes 'H' for the first time. A
The H'' output of the ND circuit 43 is input to the reset terminal of the timer 41 on the one hand to reset the contents of the timer 41 in preparation for the next turning on of the ice-making switch 30.The H'' output of the ND circuit 43 is input to the timer 42 on the other hand and is input to the reset terminal of the timer 41 to prepare for the next turning on of the ice making switch 30. The transistor 44 continues to output the Hn signal during the period a.
N, the relay coil 46 becomes conductive, the relay contact 34 closes, and the heater 26 is energized. In other words, the water temperature is approximately CTC.
The heating action from the heating plate 27 on the top surface of the first ice-making compartment 22 is started after the temperature reaches 0°C. The ice making time will be shorter. In addition, since the temperature sensor (page 2814) indirectly detects the water temperature and controls the heating start time, it is versatile even when the water temperature changes. Furthermore, since it is possible to avoid slow cooling while heating, water normally freezes into ice at the freezing point of 0°C, resulting in a supercooling phenomenon in which water is supercooled to below 0°C, making it opaque. This eliminates the risk of forming ice.

Then, the heating effect from the heating plate 27 on the upper surface prevents the water surface from freezing first, and the cooling effect from the cooling plate 13 on the lower surface causes the water to freeze in one direction from the bottom to the top, so that when time th elapses, The gaseous components contained in the water are degassed from the water surface, producing transparent ice containing almost no air bubbles. Incidentally, the time th is determined by giving a certain margin to the time required for water to pass through the maximum ice crystal formation zone of 16°C. When the time th has elapsed, the output of the timer 42 becomes "L" and the transistor 44 turns off.
L, the conduction of the relay coil 46 is cut off, the relay contact 34 is opened, and the power supply to the heater 26 is stopped. When the power supply to the heater 26 is stopped, the heating effect from the heating plate 27 disappears, and the cooling plate 1316 on the lower surface.

It is rapidly cooled by the cooling effect from

Next, while the heater 26 is energized at the time th described above, that is, during the process of producing transparent ice, there is an external thermal influence on the inside of the first ice making compartment 22, such as a cooling influence from the freezing compartment 3 or a cooling influence from the freezing compartment 3.
The ice making compartment 22 is hardly affected by the effects of heat intrusion from outside air due to the opening and closing of the door, as the bottom opening is closed by the openable and closable door body 29 provided at the front opening of the first ice making compartment 22. The formation of transparent ice can proceed under stable conditions. At the same time, the amount of heat leaking from the first ice-making compartment 22 to the outside is reduced, and the heating efficiency of the heating plate 27 is increased.As a result, the capacity of the heater 26 can be reduced, and power consumption is also reduced.

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

(1) Water begins to freeze. Since the time required to reach the temperature is short, the time required to make clear ice can be shortened. or,
It is versatile and can always demonstrate its effectiveness even under different water temperature conditions.

(2) Since it is possible to eliminate the slow cooling state by heating in the cooling section from water to ice, it is possible to prevent the occurrence of supercooling phenomenon and to prevent the mixing of opaque ice.

(3) Since the opening of the ice-making compartment is closed by the door, transparent ice can be produced under stable conditions without being affected by external heat. Furthermore, since the heating efficiency of the heating device, especially the heater, is increased, power consumption can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an ice making apparatus such as a refrigerator showing an embodiment of the present invention, Fig. 2 is a front view of the ice making apparatus shown in Fig. Figure 4 is an electric circuit and control circuit diagram of the refrigerator shown in Figure 3, and Figure 6 is a characteristic diagram when producing transparent ice with the ice making device shown in Figures 1 and 2. , FIG. 6 is a sectional view of a refrigerator equipped with a conventional ice making device. 13...Cooling plate, 16...First ice tray (ice tray), 21...Ice making device, 22...
...First ice making compartment (ice making room), 24...Insulating material, 26...Heater (heating device), 26...
... Ventilation hole, 27 ... - Heating plate, 17 Veno 28 ... Temperature sensor, 29 ... Door body. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 5
Figure 6/2 to,, /7 7 ts g /4, /δ 2', 16 ・/q 13゛4 ~ 罎======ノ ゝ

Claims (1)

[Claims] a cooling plate; an ice-making compartment partitioned with the cooling plate as the bottom and an open front; an ice-making tray stored in the ice-making compartment and placed on the cooling plate; and a heating device provided on the top surface of the ice-making tray. a heating plate comprising: a ventilation hole formed in a part of the heating plate; a temperature sensor for controlling the heating device provided in a back space of the heating plate opposite to the ventilation hole;
An ice making device such as a refrigerator, which comprises a heat insulating material disposed within an outer wall excluding the bottom and front surface of the ice making chamber, and a door that can be opened and closed provided at the front opening of the ice making chamber.