JPH0481713B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an ice making machine that is a combination of an ice making unit and an ice storage tank. The present invention relates to a structure that can constantly store high-quality ice chips while keeping ice to a minimum.

(Prior Art) An ice-making unit that repeatedly produces a predetermined amount of ice by alternately repeating an ice-making cycle and an ice-removal cycle;
An ice making machine equipped with an ice storage tank capable of sequentially receiving ice produced by this ice making unit and storing it in the form of ice pieces is known from Japanese Utility Model Application Publication No. 166475/1983. When a predetermined amount of ice chips has been stored that has reached the limit, this can be detected by an ice amount detector and the ice making unit can be forced to stop making ice from next time onwards. This ice amount detector is publicly known and was first developed in the 1980s.
The one described in Publication No. 11421 is used.

(Problems to be Solved by the Invention) As disclosed in Japanese Utility Model Publication No. 60-11421, the ice amount detector installed in the ice storage tank of a conventional ice maker is designed to detect the maximum amount of ice. If there is only one ice cube and the amount has not reached the maximum limit, the ice making unit will perform ice making operation.

In addition, in most cases, the ice making capacity of the ice making unit remains constant, and a fixed amount of ice is produced at a fixed cycle regardless of the consumption amount.

Therefore, when the amount of ice made and the amount consumed are in balance, no problem occurs, but when the amount of ice consumed is small, the next ice making operation is started only after the ice storage tank is full. When the ice is stored for a long time, the temperature inside the ice storage tank increases and the ice melts more, and the ice melts along the crystal planes and does not melt uniformly over the entire surface. Since most of the ice is made of ice, there is a problem that there is a lot of opaque ice that looks like "wrinkles", which gives an unpleasant feeling to customers and other users as ice of poor quality.

In view of these facts, the present invention adjusts the period of the ice making cycle so that the temperature rise in the ice storage tank can be automatically suppressed as the ice storage time changes depending on the consumption amount. The main purpose of this method is to prevent the formation of opaque ice chips due to the melting phenomenon, thereby improving the quality of stored ice chips.

(Means for Solving the Problems)) The present invention provides an ice making unit 1 capable of repeatedly producing a predetermined amount of ice in each ice making cycle, and an ice making unit 1 that sequentially receives the ice produced by the ice making unit 1 and converts it into ice pieces. In an ice maker equipped with an ice storage tank 2 that can store ice in close proximity to each other, a minimum ice amount detector 10 detects the minimum amount of stored ice.
At least two ice quantity detectors 10 including a maximum ice quantity detector 10B which detects the maximum ice storage quantity and issues a command to stop the ice making operation of the ice making unit 1.
Ice storage tank 2 allows multi-stage ice amount detection for A and 10B
an inverter 17 capable of outputting at least two stages of alternating current voltages with different frequencies in multiple stages;
is interposed in the power supply line connected to the compressor motor 4M of the ice making unit 1, and further receives the signals emitted by the ice amount detectors 10A and 10B as input elements, so that the amount of ice stored in the ice storage tank 2 is determined. The present invention is characterized in that a control circuit 11 is provided which gives a command to the inverter 17 to cause the inverter 17 to output a high frequency AC voltage when the voltage is low, and to output a low frequency AC voltage when the voltage is high.

(Function) The present invention drives the compressor motor 4M at high speed to replenish ice when the amount of ice stored in the ice storage tank 2 is small, and quickly produces a predetermined amount of ice. When the time is long, the compressor motor 4M is driven at a low speed to extend the ice-making cycle, thereby achieving a balance between production and consumption.At the same time, by extending the ice-making operation time, the ice storage tank 2 is heated by its cooling effect. It has been possible to suppress the natural melting of ice pieces by keeping the ice inside, thus achieving the above-mentioned purpose.

(Example) Examples of the present invention will be described in detail below based on the accompanying drawings.

FIG. 1 is a schematic structural diagram of an ice making machine, in which an ice making unit 1 and an ice storage tank 2 are integrally provided close to each other in a casing 3, and the ice making unit 1 includes a compressor 4, a condenser 5, a It consists of a fan 6 for the condenser 5, an ice-making plate 7 that acts as an evaporator, and a water circulation device, and each refrigeration device such as the compressor 4, condenser 5, and fan 6 is housed in a machine room provided in the lower part of the casing 3. On the other hand, the ice making plate 7 consisting of an obliquely installed flat plate and the water circulation device are housed in the ice making compartment 3a, which is provided in the upper part of the casing 3 and surrounded by a heat insulating material.
It is stored in.

The ice storage tank 2 is formed into a tank whose sides and bottom are surrounded by a heat insulating material and is open at the top, and is located below the ice making plate 7 to form the ice making chamber 3a.
The inside of the tank is cooled by an ice-making plate 7.

In addition, 8 in Fig. 1 is a cutting grid for making ice cubes, which has a structure in which heating wires are arranged in a grid pattern, and is installed horizontally between the ice making plate 7 and the ice storage tank 2. .

Thus, the water circulation device includes a water tray 9 disposed near the lower edge of the ice making plate 7, and a water tray 9 disposed near the lower edge of the ice making plate 7.
A circulation pump 12 provided inside, a water sprinkling nozzle 13 attached to the upper edge of the ice-making plate 7, a water pipe 15 connecting the water tray 9 and the water sprinkling nozzle 13 via the circulation pump 12, and a solenoid valve 16. Prepare raw water in water tray 9
After the raw water in the water tray 9 flows down evenly onto the smooth lower surface of the ice-making plate 9, it is dripped into the water tray 9, and then the circulation pump 12 A circulation system for feeding water to the water spray nozzle 13 is formed.

The water tray 9 is provided with an overflow pipe 18 and a water level detector 19, and the water level detector 19 is activated when the water level rises to a level slightly lower than the opening level of the overflow pipe 18. It is equipped with a water level detection switch 19a and a low water level detection switch 19b which is activated by detecting a dry water level.

The amount of water accommodated between the high water level and the dry water level at the positions where both switches 19a and 19b are activated corresponds to an amount of water slightly larger than the amount of ice sheets of a predetermined thickness produced by one ice making cycle. ing.

Although the refrigeration circuit of the ice maker with the above configuration is not shown, the discharge port of the compressor 4→condenser 5→expansion valve→
Ice making plate 7 (evaporator) → Accumulator → Compressor 4
The ice-making cycle is operated by the refrigeration cycle at the inlet, while the condenser 5 and the expansion valve are bypassed, and a hot gas bypass pipe with a solenoid valve interposed therebetween is connected to the solenoid valve. When activated by the opening operation, a well-known defrost cycle is formed and an ice removal cycle is operated.

In this way, each time an ice-making cycle and a subsequent ice-removal cycle are performed, ice plates of a predetermined thickness generated by the ice-making plate 7 are separated and cut into ice cubes by the cutting grid 8 provided below. After
The ice falls into the ice storage tank 2 and is stored there.

In the ice storage tank 2, at least two, for example, three, ice amount detectors 10A, 10B, 10C are provided on the side wall in a multi-stage arrangement in upper and lower stages, and the ice amount detector 10A at the bottom tier is the one that stores the least amount of ice. It is a minimum ice amount detector that detects whether the amount has not reached or exceeded the limit, and the ice amount detector 10B on the top stage is a maximum ice amount detector that detects whether the amount has reached the permissible limit but is below it. The middle ice amount detector 10C is an intermediate ice amount detector that detects whether the intermediate ice amount has not been reached or exceeded.

In addition, at least two ice quantity detectors are required, and two or three ice quantity detectors are required as needed.
An appropriate number of these devices can be installed in multiple stages.

Each ice amount detector 10A, 10B, 10C mentioned above
The ice maker is equipped with a control system that controls the rotation of the motor 4M for the compressor 4 using signals emitted by the compressor 4 as an input element.This control system will be explained with reference to FIG. An electromagnetic switch 20 and an inverter 17 are interposed from the power supply side in the power supply line to be connected, and when the electromagnetic switch 20 is operated to close, a frequency of, for example, 90, 60 , 30 hertz, the motor 4M is driven at high speed, medium speed, or low speed, and the capacity of the compressor is multi-staged. It has become possible to control it.

Reference numeral 21 denotes a control unit that controls the overall operation of the ice making machine, and the output terminal of this control unit 21 and the control signal input terminal of the inverter 17 are connected via the control circuit 11.

The control circuit 11 includes each ice amount detector 10A, 10
A determination unit 22 that determines the amount of ice by receiving the signals from B and 10C, and this determination unit 22
It is equipped with a command unit 23 that issues a command to convert the frequency to the corresponding frequency and to energize or de-energize the coil 20S of the electromagnetic switch 20 according to the judgment result, and performs the following operations. .

When the amount of ice in the ice storage tank 2 is small, the minimum ice amount detector 10
When the amount of ice is less than the minimum amount set in A, the determination unit 22
As a result of determining this, the command section 23 issues a 90 Hz conversion command and a command to maintain energization to the coil 20S, so the electromagnetic switch 20 closes and the inverter 1
7 outputs an AC voltage of 90 Hz, and the motor 4M is driven at high speed.

As a result, the compressor 4 operates the ice making cycle at its maximum capacity (see line A in Figure 3), and the ice making unit 1 produces a predetermined amount of ice in the shortest possible time.
The ice removed by the subsequent ice removal cycle becomes ice pieces and is stored in the ice storage tank 2.

In this way, during the period when the amount of ice in the ice storage tank 2 gradually increases and exceeds the amount set by the minimum ice amount detector 10A, but does not reach the intermediate amount set by the intermediate ice amount detector 10C, the above-mentioned determination is performed. Since the unit 22 determines that only the minimum ice amount detector 10A is on, the command unit 23 issues a 60 Hz conversion command and a command to keep the coil 20S energized.

Therefore, an AC voltage of 60 hertz is output from the inverter 17 and the motor 4M is driven at an intermediate speed, so that the compressor 4 operates the ice making cycle at the standard capacity of the intermediate value (as indicated by the line in FIG. 3). ), a predetermined amount of ice is produced in a standard time and then stored in the ice storage tank 2.

During the period when the amount of ice in the ice storage tank 2 increases further and exceeds the amount set by the intermediate ice amount detector 10C, and has not reached the maximum amount set by the maximum ice amount detector 10B, the above determination is performed. The unit 22 determines that the minimum ice amount detector 10A and the intermediate ice amount detector 10C are in the ON state, and the command unit 23 issues a 30 Hz conversion command and a command to keep the coil 20S energized. .

Therefore, an AC voltage of 30 Hz is output from the inverter 17, and the motor 4M is driven at a low speed. As a result, the compressor runs the ice-making cycle at the minimum capacity (see line C in Figure 3), and the maximum time. A predetermined amount of ice is produced and stored in the ice storage tank 2.

When the amount of ice in the ice storage tank 2 further increases and reaches the amount set by the maximum ice amount detector 10B, the determination unit 22 determines this because all the detectors 10A, 10B, and 10C are in the on state. Then, the command unit 23 issues an energization hold release command to the coil 20S.

Therefore, when the operation is currently in progress, the coil 2
The 0SS is de-energized and the ice maker stops operating (see point d in Figure 3).

Note that ice storage tank 2 is closed due to high ice consumption during ice making operation.
Needless to say, when the ice inside decreases, a command is issued to the motor 4M of the compressor 4 to increase its capacity.

In this way, depending on the amount of ice stored in the ice storage tank 2, the capacity of the compressor 4 is controlled to high frequency and high capacity when the amount of ice storage is small, and conversely to low frequency and low capacity when the amount of ice storage is large. It will be done.

As can be seen from Figure 3, which shows the operation described above as a diagram, when comparing the operation mode (shown by the broken line) of a conventional ice-making device that performs ice-making operation at a constant capacity, it is clear that the time when the amount of ice storage reaches the maximum limit. Since D in this embodiment is slower than D' in the conventional machine, the ice storage tank 2 is sufficiently cooled during this time by ice making operation, so the amount of ice melted is less than that in this embodiment. The difference in the amount of melting after a certain amount of time (△M)
can be quite large and therefore effective in preserving high quality clear ice.

Furthermore, since operation is restarted at a high capacity when nearly all of the stored ice has been taken out, ice can be produced in a shorter time than with conventional machines, and the demand can therefore be adequately met.

(Effects of the Invention) According to the present invention, when there is little ice in the ice storage tank 2, ice is made quickly with a high freezing capacity, and on the other hand, when there is a lot of ice, ice is made slowly with a low freezing capacity, so that ice consumption is reduced. When there is a large amount of ice, ice is made in a short period of time to demonstrate the ability to meet the demand.On the other hand, when consumption is low and the amount of ice in the ice storage tank 2 does not decrease, the ice making operation is performed slowly over time. Since the temperature inside the ice storage tank 2 can be maintained low by the cooling action of the ice storage tank 2, natural melting of the stored ice can be avoided, and excellent effects can be achieved in which well-shaped, transparent, and high-quality ice can be stored.

[Brief explanation of the drawing]

FIG. 1 is a schematic structural diagram according to an example of the present invention, and FIG.
The same figure is an electric circuit block diagram, and FIG. 3 is a diagram showing changes in ice storage amount over time. DESCRIPTION OF SYMBOLS 1...Ice making unit, 2...Ice storage tank, 4M...Compressor motor, 10A...Minimum ice amount detector, 10B...Maximum ice amount detector, 11...Control circuit, 17...Inverter.

Claims (1)

[Claims] 1 An ice making unit 1 capable of repeatedly producing a predetermined amount of ice for each ice making cycle, and an ice storage tank 2 capable of successively receiving the ice produced by this ice making unit 1 and storing it in the form of ice pieces are provided in close proximity. In the ice maker,
A minimum ice amount detector 10A detects the minimum ice storage amount, and a maximum ice amount detector 10B detects the maximum ice storage amount and issues a command to stop the ice making operation of the ice making unit 1.
At least two ice quantity detectors 10A, 10 including
B is arranged in the ice storage tank 2 so as to be able to detect the amount of ice in multiple stages, and an inverter 17 capable of outputting AC voltages of different frequencies in at least two stages is installed for the compressor of the ice making unit 1. It is interposed in the power supply line connected to the motor 4M, and further receives the signals emitted by the ice amount detectors 10A and 10B as input elements, and applies a high frequency AC voltage when the amount of ice stored in the ice storage tank 2 is small. An ice making machine characterized in that it is provided with a control circuit 11 which gives a command to the inverter 17 to output an alternating current voltage of a low frequency when the frequency is high.