JPS6241566A - Water pan structure of automatic ice machine and conduction control system thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a water tray structure of an automatic ice maker and its energization control system, and more specifically, the lower openings of a large number of ice making compartments can be tilted and opened by the water tray. In an automatic ice making machine that is closed and forms ice cubes in the ice making chamber by supplying water for ice making from a water tray into the ice making chamber by a fountain, breaking or preventing freezing between the water tray and the ice making chamber. By doing so, the water tray can be tilted smoothly and effortlessly during deicing, and there is no need to use water to wash the water tray to melt the frozen portion, thereby achieving economical and quiet ice-making operation. It concerns the structure and related control methods.

Prior Art An automatic ice maker that freezes water for ice making in a number of ice making chambers that open downward, and continuously produces a large number of ice cubes.
Currently, it is suitably used in facilities such as coffee shops and restaurants, as well as in various kitchens. The present invention was proposed in view of the drawbacks inherent in ice makers of the type in which the water tray tilts during ice removal. Explain with reference to. In the illustrated ice maker, partition plates 12 are arranged vertically and horizontally on the lower surface of a horizontally arranged ice maker 10 to define a large number of ice maker compartments 14 that open downward. Further, an evaporator 16 connected to a refrigeration system (not shown) is closely arranged in a meandering manner on the upper surface of the ice-making chamber 10, and during the ice-making cycle, the ice-making chamber 14 is forcibly cooled, and a fountain is supplied into the chamber by a mechanism described later. It is designed to freeze water used for ice making.

Immediately below the ice making chamber 10, as shown in the figure, a water tray 20 is inserted and supported by a pivot 18, and during the ice making cycle, this water tray 20 is positioned horizontally and closes the opening of the ice making chamber 14.
During the deicing cycle, it is biased by an actuator (not shown) to tilt about the pivot 18 to open the opening. The water ff 120 is provided with a water fountain hole 22 and a return hole 24 corresponding to each of the ice making compartments 14, and the water fountain hole 22 communicates with a distribution pipe 26 formed on the lower surface of the water tray 20. Further, an ice-making water tank 28 having the shape shown in the figure is integrally provided below the water tray 20, and is capable of storing a required amount of ice-making water 30.

A suction pipe 34 connected to a pressure pump 32 is led out from the bottom of the ice-making water tank 30, and the pump 32 is connected to a pressure chamber 36.
The pressure chamber 36 is connected to a discharge pipe 38 that communicates with the
is connected to the distribution pipe 26. Note that a water supply pipe 48 communicating with an external water system (not shown) is located above the water tray 20 and opens.

In the ice-making water circulation supply system configured in this way.

The ice-making water 30 stored in the ice-making water tank 28 is as follows.

After the ice is fed under pressure to the pressure chamber 36 through the suction pipe 34 and the discharge pipe 38 by driving the pump 32, it is distributed from the pressure chamber 36 to each distribution pipe 26, and from the water fountain hole 22 to the ice making small chamber 1.
4 is injected. At this time, the ice-making chamber 14 is cooled by exchanging heat with the refrigerant circulating in the evaporator 16 during the ice-making operation, so the ice-making water 3 supplied into the chamber is cooled.
After its temperature is lowered, the ice is returned to the ice-making water tank 28 through each return hole 24, and is again circulated and supplied to the ice-making chamber 14 by the pump 32. When the temperature of the ice-making water 30 is cooled to nearly 0° C. by repeating this process, a portion of the ice-making water begins to freeze inside the ice-making compartment 14. Further, the ice-making water that has not frozen (unfrozen residual water) falls approximately vertically from the return hole 24 of the water tray 20 and is collected in the ice-making water tank 28. As this freezing progresses and ice cubes are formed, an appropriate sensor detects this and issues an ice-making completion signal to stop the ice-making operation. Next, the deicing operation is started, and the water tray 20 is tilted to open the lower opening of the ice making chamber 14, allowing the formed ice cubes to fall and be released.

Problems to be Solved by the Invention In the automatic ice maker according to the above-described mechanism, when the ice making operation shifts to the deicing operation, the water tray 20 is tilted with respect to the ice making chamber 14 to drop and release ice cubes. However, it is not easy to actually tilt the water tray 20, and it is accompanied by various inconveniences. That is, during ice making operation, the ice making chamber 14
A strong frozen layer is formed between the lower end surface of the partition plate 12 and the water tray 20, which defines the The frozen layer will be forcibly peeled off. and water tray 20
In order to tilt, the actuator for driving requires a torque stronger than the torque that simply rotates the water tray 20 and the tank 28, and therefore a large and expensive motor is required, increasing manufacturing costs. There are some difficulties. Furthermore, the noise generated when the water tray 20 is peeled off from the ice-making chamber 14 is large, and there is a risk that cracks may occur due to the excessive mechanical load applied to the water tray 20 when the water tray 20 is peeled off.

Furthermore, as shown in FIG. 2, the remaining part of the peeled frozen layer is attached to the surface of the tilted water tray 20. For this reason, the adhered water 21 may block the fountain hole 22, or the ice cubes that have fallen from the ice-making chamber 14 may be caught in the adhered water 21, and the ice-making water may not be spouted out smoothly during the first ice-making cycle. Accidents have also occurred in which adhered water 21 is caught between the water tray and the tray 20, causing damage to the water tray and the like. Water plate 2 tilted there
In order to melt the adhering water 21 on the water supply pipe 48,
However, this means an increase in the amount of water consumed in one ice-making cycle, which is extremely uneconomical.

OBJECTS OF THE INVENTION The present invention has been proposed in view of the above-mentioned drawbacks inherent in automatic ice makers of the type in which the water tray tilts with respect to the ice making compartment during the deicing cycle, and to suitably solve these problems. ,
By removing or preventing the formation of ice between the water tray and the ice-making chamber, the water tray can be tilted smoothly and effortlessly during deicing, and the frozen portion can be melted. The purpose of this invention is to achieve economical and quiet ice-making operation by eliminating the need for spraying washing water, which was conventionally carried out for the purpose of making ice.

Embodiments Next, the structure of the water tray of the automatic ice maker and its energization control system according to the present invention will be described below using preferred embodiments. Figures 3, 5 and 7 are.

Each figure shows a cross section of a main part of an embodiment of the water tray structure according to the present invention, and the basic structure of the ice making mechanism is as described in connection with FIG. 1.

The water tray 20 according to the embodiment shown in FIG. 3 is entirely constructed of an energized heat-generating material that uniformly generates surface heat when energized. As this current-generating heat generating material, for example, a conductive resin mixed with fine powder of carbon, metal, etc. to have conductive properties is suitably used.

By injection molding this resin material, the water fountain hole 22,
Return hole 242 distribution pipe 26. Water tray 20 with pressure chamber 36
are integrally molded. Since the conductive resin is endowed with conductive properties, it uniformly generates surface heat when electricity is applied to it, effectively melting the frozen part formed between the ice-making chamber 14 and the water tray 20 during ice-making operation. can be done. The conductive resin in this example is used in water dishes and is exposed to wide temperature changes from below zero to room temperature, so the conductivity does not change and the formability is low. It is necessary to meet requirements such as rigidity, impact strength, and dimensional accuracy.

In order to supply power to the water dish 20, which is integrally molded with conductive resin, as shown in FIG. , is configured to do this by connecting to a low voltage power supply as described in connection with FIG. Examples of specific attachment of the electrode 51 are shown in FIGS. 9 and 10. That is, as shown in FIG. 9, when the water tray 20 is molded from a conductive resin, the electrode 51 is integrally embedded in the side surface of the water tray 20, or as shown in FIG. It is proposed that the electrode 51 be glued via a conductive adhesive (eg Dotite) 57.

Note that when adhering with the conductive adhesive 57, the electrode 51 is exposed on the side surface of the water dish, so it is preferable to cover it with an insulating cover made of resin. In addition, the mounting position of the electrode 51 is adjusted so that the heat generation resistance of the conductive resin is the best.
If necessary, it may be fixed to the back surface of the water tray 20 as shown in FIG.

FIG. 5 shows another embodiment, in which a part of the water tray 20 is made of an energized heat generating material. That is, only the upper surface of the water tray in which the fountain hole 22 and the return hole 24 are formed is covered with the conductive resin 5.
5, and the other parts are molded from ordinary ABS resin. In this case, there is an advantage that the amount of relatively expensive conductive resin used can be reduced. Conductive resin 5 at this time
The position of attachment of the electrode 51 to the electrode 5 is as shown in FIG. 6, and the specific means are as described in connection with FIGS. 9 and 10.

FIG. 7 shows yet another embodiment in which a portion of the water tray 20 is made of an electrically conductive heat generating material. In this case, a plate material with a required number of fountain holes 22 and return holes 24 is made of conductive resin 55.
This conductive plate material 55 is affixed correspondingly to the upper surface of a water tray 20 (having a fountain hole 22 and a return hole 24) molded from ordinary ABS resin. In this case as well, the position and specific means for attaching the electrode 51 to the conductive resin 55 are as described in connection with FIGS. 6, 9 and 10.

In addition to conductive resin, a ceramic heater is preferably used as the electrically conductive heat generating material constituting the water tray 20.

This ceramic heater has a base material formed by, for example, molding alumina ceramic into a water tray 20 of a predetermined shape, printing a resistor pattern on the alumina sheet, and laminating the resistor pattern with an alumina insulating layer. This is also a device that can generate surface heat by supplying electricity to the resistor.

As yet another modification, the electrically conductive heat generating material may be configured such that the water tray 20 is molded from an appropriate resin material such as ABS, and a conductive paint is applied to appropriate locations on the resulting resin molded member. good. This conductive paint can be made of, for example, carbon,
Conductive particles such as graphite, copper, silver, and nickel dispersed in a resin binder are used, and the coating methods include vacuum evaporation, metal spraying, sputtering, and ion blating. be done.

In the water tray structure of the ice maker according to the present invention configured as described above, electricity is supplied to the current-carrying heat-generating material such as a conductive resin forming all or a part of the water tray 20 by the ice maker control circuit shown in FIG. 11. will be executed at the required timing. The ice maker control circuit, which has a built-in microcomputer central processing unit (CPU), is equipped with an ice making/deicing thermometer Th, a water tray thermometer Th, and a water storage detection switch SW1 as ice maker status detection elements. Based on the detection data input by the elements, commands are given to various output groups. This output group is, for example, a compressor (CM), a fan motor (FM), a pump motor (PM), a water valve (WV>, a hot gas valve (HGV), an actuator motor (AM), and a 100v power input is , separate transformer S
Safety measures are taken to separate the ground potential via T and lower the voltage to a low voltage of several volts to several ov to prevent danger from spreading to the human body.

Next, the timing of energizing the energizing heat generating member constituting all or part of the water tray 20 will be explained.

When the ice-making cycle is started, the ice-making water 30 in the ice-making water tank 28 is pumped into the pressure chamber by the pump 32.

36 and distribution pipe 26, and is injected from the water fountain hole 22 of the water tray 20 into the corresponding ice making chamber 14.

Since the ice-making chamber 14 is cooled by the evaporator 16, the ice-making water 30 comes into contact with the wall of the ice-making chamber and is cooled, and then flows down from the return hole 24 of the water tray 20 to the ice-making water tank 28.
to return to. In this way, the ice making water 30 is transferred to the ice making water tank 2.
As the water circulates between the ice-making chamber 14 and the ice-making chamber 14, the temperature of the ice-making water gradually decreases, and when the temperature reaches nearly 0°C,
A portion of the ice-making water begins to freeze on the inner wall of the ice-making chamber 14.

In this way, freezing progresses gradually in each ice making compartment 14,
Eventually, dense ice cubes are produced. At this point, a solid layer of ice is formed between the downward opening of the ice-making chamber 14 and the upper surface of the water tray 20, as described above.

When the ice cubes are completely formed in this way, the temperature in the ice making chamber 10 drops, and this is detected by the ice making thermometer, and the operation of the pump motor PM and fan motor FM is stopped, and the ice making is started. Complete.

When this ice making is completed, electricity is supplied to the energized heat generating material constituting all or a part of the water tray 20 via the separate transformer ST and the electrode 51, whereby the water tray 20 starts generating heat. This increases the surface temperature and starts melting the frozen layer formed between the ice making chamber 14 and the water tray 20. At the same time, the hot gas valve HGV is switched, and hot gas flows into the evaporator tube 16 to heat the ice making chamber 10 (start of deicing operation).As can be seen from FIG. At this point, the actuator motor AM is not yet energized, so the water tray 20 maintains its horizontal position without tilting.

As mentioned above, since electricity has already been applied to the energized heat generating material of the water tray 20, the frozen portion between the water tray 20 and the ice making chamber 14 is gradually melted due to the heat generated, and the solid state between the two members is gradually melted. The knot is starting to loosen. In addition, the ice making chamber 10 is heated by the hot gas, and the ice cubes and the inner wall surface of the ice making chamber 14 are beginning to loosen. Such a temperature change in the water tray 20 is monitored and detected by the water tray thermometer Th, and at a timing when the water tray 20 can be peeled off from the ice making compartment 14,
The actuator motor AM is energized to tilt the water tray 20. At this time, since the frozen portion between the water tray 20 and the ice-making chamber 14 has loosened, the water tray 20 is smoothly peeled off from the ice-making chamber 14 and lowered without applying an excessive load. Note that instead of using the water pan thermometer Th2, the temperature rise time required for melting and peeling off the frozen portion is set in advance by a timer, and when the settling time expires, the motor AM is energized to tilt the water pan 20. In either case, the actuator motor AM for urging the water tray 20 to rotate does not require a torque strong enough to forcibly peel off a solid frozen part, and a small and inexpensive one is used. It is possible to do so. Moreover, the peeling sound of the frozen part during tilting is small, and no unreasonable load is applied to the water tray 20 itself, so that a quiet ice-making operation with fewer breakdowns is achieved. Water tray 20 after further tilting
Since the frozen pieces slide off the surface of the water tray, there is no need for washing water, which was conventionally sprayed to melt the remaining frozen pieces on the water tray.

In this energization control method, energization to the energized heat generating material of the water tray 20 is started at the same time as ice making is completed, and after it is detected that the ice between the ice making chamber 14 and the water tray 20 has melted, the lowering of the water tray 20 is stopped. It is a start. However, with this control method, if the ice maker is operated when the outside temperature is high, the time it takes for the temperature of the water tray 20 to rise may be longer than the time required to separate the ice cubes from the ice maker 10. This means that before the water tray 20 tilts and begins to descend, the ice cubes are already melting wastefully in the ice making chamber 10, and the deicing time tends to be slightly longer. be.

Therefore, in order to shorten the time for the temperature of the water tray 20 to rise after ice making is completed, it has been proposed to start energization during ice making using another energization control method. That is, as shown in FIG. 13, energization of the energized heat generating material of the water tray 20 is started during ice making and near the completion of ice making to raise the temperature of the water tray 20, and the temperature of the water tray 20 is raised. The water tray 20 is controlled to start descending after the frozen part of the water tray 20 is thawed. For example, before the ice making is completed and at an appropriate time during the ice making, the ice making/deicing thermometer Th detects a temperature slightly higher than the ice making completion temperature, and starts energizing the water tray 20 during the ice making.

In this case, even if the ice making operation is performed when the outside temperature is high, the temperature rise time of the water tray 20 will not be longer than the time required to separate the ice cubes from the ice making compartment 10. This eliminates wasteful melting of ice cubes, and furthermore, it is possible to set a shorter deicing time until the start of ice making.

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, in an automatic ice maker in which the lower openings of a number of ice-making chambers are closed by a water tray in a tiltable and openable manner, there is a strong connection between the water tray and the ice-making chambers during ice making. A device capable of melting the frozen portion that forms before the water tray starts tilting or preventing the formation of the frozen portion by energizing the energized heat-generating material that constitutes all or part of the water tray. It is. Therefore, the following advantages can be obtained.

■The actuator that rotates the water tray does not require strong torque and can be small and inexpensive. Further, when the frozen part peels off, the load applied to the water tray and the ice-making compartment is small, so the frequency of breakdowns is reduced and peeling noise can be kept low.

■As the surface of the water tray generates heat and the contact surface with the ice cubes melts, the water tray tilts and the ice cubes that fall and are released from the ice-making chamber become smooth on each surface and deformed in appearance. You can get high quality ice without any ice.

■As shown in FIG. 14(,) and FIG. 14(b).

Conventionally, frozen parts 21 remain on the water tray 20, and the ribs 21a connecting adjacent ice cubes become discontinuous in the middle, so that when the water tray 20 is tilted, the ice cubes fall apart. Therefore, as shown in the figure, some of the ice cubes may remain in the ice making compartment 14 and the surrounding area may be melted wastefully. On the other hand, according to the present invention, FIG. 1!5(a) and FIG. 15(b)
As is clear from the above, since the ribs 21a connecting the ice cubes formed in the adjacent ice making compartments 14 remain neatly, after the water tray is tilted, the ice cubes fall all at once and fall into the water storage tank (not shown) directly below. Inside, the ice cubes are broken into individual ice cubes at the ribs 21a, thereby eliminating wasteful melting of ice in the ice making chamber 10.

(2) Furthermore, in the present invention, since the water tray 20 is made of an electrically conductive heat-generating material and is energized, there is no possibility that ice will form in the fountain hole 22 and the return hole 24 of the water tray 20 and block them. Nor. Since no frozen portion remains on the surface of the water tray 20 as described above, there is no need to spray washing water onto the tilted water tray 20 to melt the frozen portion as in the conventional method, and the amount of water consumed can be saved. Furthermore, even when the water tray 20 returns to the upper position and starts the next ice-making cycle, the water fountain hole 22 and the return hole 24 are not blocked by the frozen part, and the ice-making chamber 1
4 and the water tray 20, there is no chance of mechanical damage caused by the frozen part being caught between the water tray 20 and the water tray 20.

[Brief explanation of the drawing]

1 and 2 are schematic diagrams showing the structure of a water tray of an ice maker according to the prior art, in particular, FIG. 2 shows a tilted state of the water tray, and FIG. 3 is a diagram showing a water tray according to the present invention. A schematic side view of the structure, FIG. 4 is a plan view showing the electrode connection state of the water dish, FIG. 5 is a schematic side view of another water dish structure according to the present invention, and FIG. 6 is the electrode connection of the water dish. FIG. 7 is a schematic side view of still another water dish structure according to the present invention, FIG. 8 is a plan view showing the electrode connection state of the water dish, and FIGS. 9 and 10 are respectively An explanatory diagram showing the state of electrode connection to the energized heat generating material constituting the water tray, FIG. 11 is a schematic diagram of a control circuit used in the energization control method of the ice maker according to the present invention, and FIGS. 12 and 13 are respectively FIG. 14 (a
) and FIG. 14(b) are explanatory diagrams showing how ice cubes fall over time when the water tray is tilted in a conventional ice maker, and FIG.
a) and FIG. 15(b) are explanatory diagrams showing how ice cubes fall over time when the water tray according to the present invention is tilted. 10...Ice making compartment 14...Ice making compartment 20...
・Water tray 22...Fountain hole 24...Return hole
28... Ice making water tank 30... Ice making water FIG, 1 FIG, 2 FIG, 3 FIG, 4 FIG, 5 FIG, 6 FIG, 7 FIG, 8 FIG, 9 FIG, 10 FIo, 15 FIG, 14

Claims (6)

[Claims] (1) An ice-making chamber 10 defining a large number of ice-making chambers 14 that open downward; the openings of the ice-making chambers 14 are obstructed so as to be tiltable and openable from below; and a water fountain 22 and a fountain hole 22 corresponding to each opening; A water tray 20 with a return hole 24 and an ice-making water tank 28 integrally formed below the water tray 20.
Then, the ice-making water 30 in this tank 28 is poured into the water fountain 22.
A water fountain is supplied to the ice-making chamber 14 to form ice cubes in the ice-making chamber 14, and the water tray 20 is placed in the ice-making chamber 1 during deicing.
4. A water tray structure for an automatic ice maker, characterized in that the water tray 20 is entirely or partially constructed of an energized heat-generating material in an automatic ice maker which is tilted relative to the base of the ice cube to drop and release the obtained ice cubes. (2) The water tray structure for an automatic ice maker according to claim 1, wherein the electrically conductive heat generating material is a conductive resin mixed with fine powder such as carbon or metal to have conductive properties. (3) The electric heating material is a ceramic heater made by, for example, molding alumina ceramic into a predetermined shape and laminating a resistor pattern printed on the alumina sheet with an alumina insulating layer. automatic ice maker water tray structure. (4) The water tray structure for an automatic ice maker according to claim 1, wherein the electrically conductive heat generating material is formed by applying conductive paint to appropriate parts of a resin-molded water tray. (5) An ice-making chamber 10 defining a large number of ice-making chambers 14 that open downward, the opening of the ice-making chamber 14 being closed from below so as to be tiltable and openable, and constructed in whole or in part from an energized heat-generating material. Also, a fountain hole 2 corresponding to each opening.
2 and a return hole 24, an ice-making water tank 28 integrally formed below the water tray 20,
The ice-making water 30 in the tank 28 is supplied from the fountain hole 22 to the ice-making chamber 14 to form ice cubes in the ice-making chamber 14, and the water tray 20 is tilted relative to the ice-making chamber 14 during deicing. In an automatic ice maker that drops and discharges the obtained ice cubes, the temperature of the water tray 20 is increased by starting energizing the energized heat generating material of the water tray 20 when ice making is completed;
An energization control system characterized by controlling the water tray 20 to start lowering after the ice cubes formed in the ice making chamber 14 and the water tray 20 are thawed. (6) An ice-making chamber 10 defining a large number of ice-making chambers 14 that open downward, the opening of the ice-making chamber 14 being obstructed so as to be tiltable and openable from below, and constructed entirely or partially of an energized heat-generating material. Also, a fountain hole 2 corresponding to each opening.
2 and a return hole 24, an ice-making water tank 28 integrally formed below the water tray 20,
The ice-making water 30 in the tank 28 is supplied from the fountain hole 22 to the ice-making chamber 14 to form ice cubes in the ice-making chamber 14, and the water tray 20 is tilted relative to the ice-making chamber 14 during deicing. In an automatic ice maker that drops and discharges the obtained ice cubes, the temperature of the water tray 20 is increased by starting energizing the energized heat generating material of the water tray 20 during ice making and at a point close to the completion of ice making. An energization control system characterized in that the water tray 20 is controlled to start descending after the ice cubes formed in the ice making chamber 14 and the water tray 20 are thawed.