JP2002295931A - Automatic ice maker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an automatic ice maker in which ice can be made while supplying water accurately. SOLUTION: An infrared sensor 7 is disposed above an ice making pan 4 in order to receive infrared rays reflected on the water supplied into the ice making pan 4. Based on an output signal from the infrared sensor 7, the water level decision means 10 and the ice making completion decision means 9 in a decision means 8 decide the level of water/ice in the ice making pan 4 and completion of ice making respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic ice making machine used for a refrigerator.

[0002]

2. Description of the Related Art FIG.
FIG. 8 is a front view showing a conventional automatic ice making machine disclosed in
Is a sectional view, and FIG. 9 is a principle block diagram. In the figure,
21 is a refrigerator-freezer body, 22 is an ice tray, 23a is an ice-making corner body for placing the ice tray 22 and making ice, 23b is a stopper for appropriately keeping the position of the ice-making tray 22, and ice-making corner body 23a and stopper 23b are for freezing. It is provided in the chamber 21a. 24 is a fan grill for blowing cold air in a predetermined direction in the freezer compartment 21a, 25 is an ice making corner 23
An infrared sensor arranged on the ice tray 22 so as to be directly above the ice tray 22; 26, a cylindrical holder for holding the infrared sensor 25; 27, a freezing compartment ceiling to which the cylindrical holder 26 is fixed;
Is a microcomputer having a function of processing and judging an electric signal from the infrared sensor 25, 29 is a light emitting diode which is turned on when ice making is completed by a judgment signal from the microcomputer, 30 is a freezer door for fixing the light emitting diode 29 to a door panel, Reference numeral 31 denotes water injected into the ice tray 22.

The operation of such a conventional automatic ice maker will be described. 8, the cool air blown from the fan grill 24 passes through a space defined by the ice making corner main body 23a and cools the water 31 in the ice making tray 22. The ceiling 27 constitutes a section for ice making together with the ice making corner main body 23a, and the infrared sensor 25 is fixed vertically downward in the hollow portion of the cylindrical holder 26 near the opening on the freezer door 30 side. The infrared sensor 25 is electrically connected to the microcomputer 28. The microcomputer 28 and the light emitting diode 29 are also electrically connected to form an ice making detection circuit for judging a series of ice making completion.

[0004] Next, based on the principle block diagram of FIG.
The ice making detection circuit will be described. First, the infrared energy of the water 31 in the ice tray 22 is detected by the infrared sensor 25 as the amount of infrared radiation. The detection result of the amount of infrared radiation detected by the infrared sensor 25 is sent out as an electric signal and input to a detection signal control circuit 28a of the computer, where it is sufficiently amplified and detected signal comparison circuit 28
The comparison circuit 28b determines whether or not the ice making is completed. When the ice making is completed, the light emitting diode 29, which is a display device connected to the comparing means 28b, emits light.

[0005]

In the conventional automatic ice maker described above, when water is supplied to the ice tray 22 from a water tank by a water supply pump through a water supply pipe, a predetermined time is determined by the operation time of the water supply pump. To obtain the required amount of water. However, when the water in the water tank is insufficient, the water supply pipe is clogged, or the water supply is insufficient due to a malfunction of the water supply pump, the water 31 in the ice tray 22 is not provided.
The ice making is determined in a state where the amount of ice is small, the size and thickness of the completed ice are not uniform, or the ice is broken finely at the time of ice removal, and the ice becomes inconvenient when used by the user. there were. In addition, if the last ice separation is incomplete and ice remains in the ice tray 22, when a predetermined amount of water is supplied by operating the water supply pump for a predetermined time, the amount of water 31 in the ice tray 22 is reduced. When the ice is larger than necessary, the ice is unnecessarily large and the ice separation is incomplete, or when an ice tray is provided below the ice tray 22, the water 31 is discharged from the ice tray 22. There was a problem that water overflowed into the ice tray and overflowed, and the ice in the ice tray was connected to be solidified.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide an automatic ice making machine for making ice with an accurate water supply.

[0007]

An automatic ice maker according to the present invention has an infrared sensor for detecting the thermal energy of water above an ice tray of a refrigerator, and ice is produced from a sensor output from the infrared sensor. A determination means for determining the water level in the dish and the completion of ice making is provided.

The determining means comprises ice making determining means for determining the completion of ice making from the output of the infrared sensor and water level determining means for determining the water level of the ice tray from the output of the infrared sensor.

When the determining means determines that the amount of water in the ice tray is not an appropriate amount of water, the determining means adjusts the amount of water so that the amount of water in the ice tray becomes an appropriate amount of water, and then detects the completion of ice making. It was made.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a block diagram showing an automatic ice making machine according to Embodiment 1 of the present invention. In the figure, reference numeral 1 denotes a water tank for storing water, 2 denotes a water supply pipe for sucking water from the water tank 1, 3.
Is an ice tray for pumping water from the water tank 1, 4 is an ice tray for storing water supplied from the water tank 1 through the water supply pipe 2 and supplied by the pump 3 and making ice, and 5 is rotating the ice tray 4. Means for rotating an ice tray for ice removal, 6 for an ice tray for storing ice removed from the ice, 7 for an infrared sensor for measuring the temperature of water supplied to the ice tray, 8 for the output of the infrared sensor The determination means for detecting the completion of ice making and the water level from the signal is composed of an ice making completion determination means 9 for detecting the completion of ice making and a water level determination means 10 for detecting the level of water supplied to the ice tray.

The operation of the automatic ice maker constructed as described above will be described. First, water in the water tank 1 is sucked up by the pump 3 through the water supply pipe 2 and supplied to the ice tray 4. The pump 3 operates for a predetermined time to supply water. The operation time is determined from a predetermined appropriate water amount and a water supply amount per unit time when the pump 3 operates normally. For example, if the appropriate water volume is 200 mL and the unit time water absorption of the pump is 20 mL / second, the pump operation time is predetermined to 10 seconds.

Next, a method of detecting a change in the water level of the ice tray 4 during water supply will be described, taking as an example a case where the appropriate amount of water in the ice tray 4 is 200 mL and the amount of water supplied to the pump 3 per unit time is 20 mL / second. 2 is a sectional view of an ice tray immediately after the start of water supply, FIG. 3 is a sectional view of an ice tray 5 seconds after the start of water supply, and FIG.
It is an ice tray sectional view at the time of lapse of seconds (at the time of completion of water supply). In the figure, 11 is the bottom of the ice tray, and 12 is the side of the ice tray. First, the water level of the ice tray 4 is changed from the water level 13 immediately before the start of water supply after the ice is completely removed, that is, the water level 13 at which the pump 3 starts to supply water from a state where no water is supplied (see FIG. 2). At the elapse of the second, the water level reaches the 50% water supply level 14 (see FIG. 3), and at the elapse of 10 seconds after the pump 3 operates, the water level reaches the proper water level 15, that is, the 100% water supply level (see FIG. 4). As described above, when water is supplied for the predetermined operation time of the pump 3, the water level of the ice tray 4 rises and the water supply is completed to an appropriate water level.

An area for receiving infrared radiation of the ice tray 4 by the infrared sensor 7 in response to such a change in the water level in the ice tray 4 will be described. In the case where a small amount of water is supplied to the ice tray 4 shown in FIG. Receives infrared radiation from the water supply from each of the regions A and B, receives infrared radiation from the ice tray from the regions a, b, and c, and receives the total energy of these. Here, the infrared radiant energy is determined by the temperature and emissivity of the object.The infrared radiant energy is low when the temperature is low, and the infrared radiant energy is high when the temperature is high, and an output signal is output according to the intensity. You. Usually, the temperature of the supply water is about 5 ° C., and the ice tray 4 is cooled to cool air to about −20 ° C. That is, comparing the entire light receiving area of the infrared sensor 7 of the ice tray 4 before water supply with the entire light receiving area of the infrared sensor 7 in a state where the water supply is small (FIG. 2), the water supply is small by the amount of energy received from the water supply. State becomes larger. When the water supply shown in FIG. 3 reaches a 50% state, the area of the water surface of the ice tray 4 increases, and the infrared sensor 7 calculates the sum of the areas C, D having large radiant energy and the areas d, e, f having small radiant energy. Receives energy. The areas C and D on the water surface are larger than the areas A and B on the water surface, and the output of the infrared sensor 7 is also larger. When the water supply further proceeds and reaches 100% of the proper water level shown in FIG. 4, the area of the water surface further increases, and the infrared sensor 7 outputs the total energy from the area E having large radiant energy and the areas g and h having small radiant energy. Is received. Area E
Has a larger area than the regions C and D described above,
The output of the infrared sensor 7 also has a large value.

The output signal of the infrared sensor 7 with respect to the change of the infrared radiation received as described above will be described with reference to FIG. Reference numeral 16 denotes a graph showing the amount of water supplied to the ice tray 4, which increases in proportion to the time from the pump start time X to the pump stop time Z because the pump 3 is operated with a constant water supply power. Then, after the pump stop time Z, the water supply stops, and the supply water amount becomes constant. On the other hand, reference numeral 17 denotes a graph showing the output signal value of the infrared sensor. The time from when the pump 3 starts to operate to start supplying water to the ice tray 4 until the bottom of the ice tray 11 is covered with water. Until Y, it increases rapidly in proportion to time. And ice tray 4
The slope becomes gentle from the time Y when the bottom surface 11 is covered with the water supply to the pump stop time Z, increases almost in proportion to the time, and becomes a constant output signal value after the pump stop time Z.

As described above, the output signal of the infrared sensor 7 increases as the water level in the ice tray 4 rises.
When the pump 3 operates normally and supplies water, as shown in FIG. 5, the supply water amount 16 and the infrared sensor output signal value 17 from the pump start time X to the time Y in which the bottom portion 11 is covered with the supply water. And a proportional relationship holds. Therefore, the supply water amount value at the time of normal water supply can be obtained from the infrared sensor output signal value 17. Also, the bottom part 1 of the ice tray
Pump stop time Z from time Y when 1 is covered with water supply
During this period, a proportional relationship is established between the supplied water amount 16 and the infrared sensor output signal value 17, and the infrared sensor output signal value 1
From 7, it is possible to determine the supply water value during normal water supply.

As described above, since the amount of water supply in the ice tray 4 can be accurately detected, when it is determined that the amount of water supply is small, the amount of water supply is predicted, and the operating time of the pump 3 is increased by setting the pump 3 to an appropriate amount of water. When the amount of water in the ice tray 4 does not increase even if the operation time of the pump 3 is added, it is considered that the water in the water tank 1 is insufficient. To make the amount of water in the ice tray 4 an appropriate amount of water.

When the amount of water does not reach the appropriate amount of water, ice may not be separated, and fine ice may not be formed. In addition, a switch to specify the size of ice is provided,
The size of the ice may be freely changed according to the adjustment of the operation time of the pump 3 and the measurement information of the water level to make the ice.

Next, detection of completion of ice making by the infrared sensor 7 will be described with reference to FIG. Numeral 18 is a graph showing the temperature change of water / ice itself, which is the object of ice making, from the water supply start A to the water supply completion B, the water temperature is gradually supplied from the water tank 1 into the ice tray 4 while being gradually lowered. When water is supplied to the ice tray 4, the temperature gradually decreases due to the surrounding cooling effect. When the temperature decreases to a temperature C near 0 ° C., the temperature stabilizes around 0 ° C. for a while thereafter. After the end of the temperature stabilization D, the temperature starts decreasing again and the ice making is completed E. The time from ice making start A to ice making completion E takes about 40 to 60 minutes. On the other hand, 19 is a graph showing the relative value of the output signal of the infrared sensor 7, and after the ice making and water supply start A, water of about 5 ° C. in the water tank 1 is supplied to the ice tray 4, as shown in FIG. The ratio of the water surface area in the light receiving area of the sensor 7 increases, the output signal of the infrared sensor 7 increases, and reaches a peak when the water supply is completed B. Thereafter, the temperature of the water is reduced by cooling, and the relative value 19 of the output signal of the infrared sensor 7 is also reduced. When the temperature drops to a temperature C around 0 ° C., the temperature stabilizes around 0 ° C. for a while, and after 0 ° C. is stabilized, the temperature starts decreasing again. Reach.

As described above, the change 19 in the relative value of the output signal of the infrared sensor 7 after the completion of the water supply B is caused by the fact that the infrared sensor 7 directly measures the infrared radiation energy related to the temperature emitted from water and ice. It shows a change similar to the change 18 in the temperature of water and ice in the ice tray 4, so that the temperature of the ice itself can be measured and detected. A good automatic ice machine can be obtained.

Here, the output of the thermistor is compared with the temperature equivalent value 20. The temperature equivalent value 20 of the output of the thermistor does not rise to the water temperature due to the thermal resistance of the ice tray 4 and the effect of the other side of the thermistor being cooled by cold air at the completion of water supply B of the automatic ice maker. The temperature e becomes lower than 0 ° C., and before reaching the ice making completion time E, the temperature e drops to the ice making completion judgment reference temperature value d.
It means that the ice removing operation is performed while the ice is not made.

As described above, water from the infrared sensor 7
By detecting the temperature of the ice, the amount of water in the ice tray 4 is adjusted with an appropriate amount of ice, and the completion of ice making is determined from the temperature of the ice itself. It is possible to provide ice of uniform shape and to determine both the amount of water in the ice tray 4 and the completion of ice making by the infrared sensor 7, so that the number of parts is not increased.

Since the ice making completion judging means 9 and the water level judging means 10 make the judgment by the signal from the infrared sensor 7 which can make judgment without touching the ice making tray 4, the ice making tray 4 is determined.
It is not necessary to have a structure that requires an electrical connection, and a structure in which the ice tray 4 can be easily removed can be easily realized. The user can easily remove the ice tray 4, wash the ice tray 4, and obtain a sanitary automatic ice machine. be able to.

[0023]

Since the present invention is configured as described above, it has the following effects.

An infrared sensor for detecting the thermal energy of water is provided above the ice tray of the refrigerator, and a judging means for judging the water level in the ice tray and the completion of ice making from the sensor output from the infrared sensor is provided. Therefore, ice making can be accurately completed with an appropriate amount of water, and ice of uniform shape can be reliably provided.

The determining means comprises ice making determining means for determining the completion of ice making from the output of the infrared sensor and water level determining means for determining the water level of the ice tray from the output of the infrared sensor. Ice making completion detection and water level detection can be made possible by the temperature of water and ice, and more accurate ice making completion and water level determination can be performed.

When the determining means determines that the amount of water in the ice tray is not an appropriate amount of water, the determining means adjusts the amount of water so that the amount of water in the ice tray becomes an appropriate amount of water, and then detects completion of ice making. The water supply is reduced,
The ice making can be completed accurately, and ice storage of the same size can be provided without freezing the ice storage due to ice separation with unmade ice or without wasting power by cooling for a long time.

[Brief description of the drawings]

FIG. 1 is a block diagram of an automatic ice maker showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a main part of the automatic ice maker showing the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of a main part of the automatic ice maker showing the first embodiment of the present invention.

FIG. 4 is a cross-sectional view of a main part of the automatic ice maker showing the first embodiment of the present invention.

FIG. 5 is a diagram illustrating a relationship between a pump operation time and an infrared sensor output signal value of the automatic ice maker according to the first embodiment of the present invention.

FIG. 6 is a diagram showing a temperature change of water and ice and a change of an infrared sensor output signal during ice making of the automatic ice making machine according to the first embodiment of the present invention.

FIG. 7 is a front view showing a conventional automatic ice maker.

FIG. 8 is a sectional view showing a conventional automatic ice maker.

FIG. 9 is a principle block diagram showing a conventional automatic ice maker.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Water tank, 2 water supply pipes, 3 pumps, 4 ice trays, 5 ice tray rotating means, 6 ice trays, 7 infrared sensors, 8 determining means, 9 ice making completion determining means, 10 water level determining means, 11 bottom part, 12 side surfaces Part, 13 Water level at the beginning of water supply, 1 50% water supply level, 15 Water supply,
16 Water supply amount, 17 Infrared sensor output signal value, 18
Temperature of water / ice itself, 19 relative value of output signal of infrared sensor, 20 equivalent value of output temperature by thermistor.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Katsumasa Sakamoto 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 3L110 AA07 AB00 AC04

Claims (3)

[Claims] An infrared sensor for detecting thermal energy of water is provided above an ice tray of a refrigerator, and a determination means for determining a water level in the ice tray and completion of ice making from a sensor output from the infrared sensor. An automatic ice maker characterized by being provided. 2. The apparatus according to claim 1, wherein said determining means comprises ice making determining means for determining completion of ice making from the output of the infrared sensor and water level determining means for determining the water level of the ice tray from the output of the infrared sensor. 2. The automatic ice maker according to 1. 3. When the determination means determines that the amount of water in the ice tray is not an appropriate amount of water, the determination means adjusts the amount of water so that the amount of water in the ice tray becomes an appropriate amount of water, and then detects completion of ice making. 3. The automatic ice making machine according to claim 1, wherein