JPH0334625Y2 - - Google Patents

Description

[Detailed description of the invention] a. Industrial application field The present invention relates to an operation control device for an ice maker, and in particular,
This invention relates to new improvements for preventing overload on a compressor when deicing is performed using a combination of hot gas and deicing water, and for ensuring reliable deicing regardless of ambient temperature and water temperature.

b. Conventional technology In general, hot gas alone is often used as a deicing means for ice makers that have been used in the past, but depending on the structure of the ice maker, hot gas alone may not be sufficient. . For example, in the case of a structure in which a large number of ice particles are formed by using an ice-making plate formed in a longitudinally corrugated stainless steel plate, it is not possible to simply flow hot gas into the evaporator, causing ice to form on the surface of the ice-making plate corresponding to the evaporator. Although ice melts quickly, the ice in the area away from the evaporator is not easily melted and requires a long deicing time, resulting in a decrease in ice-making ability and deterioration in ice shape, resulting in a decrease in product quality.

In addition, in the case of a configuration that uses both hot gas and deicing water, the hot gas valve should have a small diameter to prevent the compressor from overloading under conditions where the ambient temperature or the water supply temperature for deicing is high. On the other hand, under conditions where the ambient temperature or the water supply temperature is low, the deicing time becomes extremely long due to the insufficient flow rate of hot gas, and there are cases where deicing is not completed.

Also, contrary to the above-mentioned configuration, in the case of a configuration in which the valve diameter is increased, it is advantageous under low temperature conditions, but conversely, under high temperature conditions, the pressure of the refrigerant gas discharged and sucked from the compressor decreases. This caused the compressor to become extremely overloaded, making normal operation impossible and causing the compressor to malfunction.

In other words, when hot gas and deicing water are used together, under high temperature conditions, as is clear from the comparison of specific heat, water has overwhelmingly large thermal energy, and according to the applicant's experiments, the effect of hot gas on deicing is is about 1/5 of water, and from this fact it can be understood that it is an important element in solving the above-mentioned problem.

c. Problems to be solved by the present invention In the conventional configuration as described above, when hot gas and deicing water are used together during deicing, the deicing time takes a long time depending on the ambient temperature or the water supply temperature. As a result, the ice making capacity changed drastically and the ice making capacity sometimes decreased.

Furthermore, under high temperature conditions, the pressure of refrigerant gas discharged and taken in from the compressor increases significantly, resulting in significant overload of the compressor, making it difficult to perform deicing operations without overloading the compressor. It was impossible.

d. Means for solving the problems The purpose of the present invention is to provide extremely effective means for quickly eliminating the above problems, and its gist is as follows: a deicing completion detection temperature switch installed in an ice making unit having an evaporator connected to a compressor and detecting the completion of deicing by detecting the temperature of the ice making unit;
a hot gas valve connected to the deicing completion detection temperature switch and supplying hot gas to the evaporator; a water supply valve that opens at the start of the deicing process for supplying deicing water to the ice making section; a timer for controlling the water supply valve, which is connected to the water supply valve and starts a time-limited operation at the start of the deicing process and closes the water supply valve when the set time limit has elapsed, the deicing completion detection temperature switch, the hot gas valve, the water supply valve, and the water supply valve. and a control circuit unit connected to a control timer, and the set time limit of the water supply valve control timer is such that the deicing completion detection temperature switch detects the completion of deicing under high to medium ambient temperature or high to medium water supply temperature conditions. The deicing completion detection temperature switch detects the completion of deicing under conditions of low ambient temperature or low water supply temperature. In the deicing process under high or medium temperature conditions, the hot gas valve is first closed and then the water supply valve is closed; in the deicing process under low ambient temperature or low feed water temperature conditions, the An operation control device for an ice maker is characterized in that the hot gas valve is controlled to be closed after the water supply valve is closed.

e Effect The water supply valve is controlled by the water supply valve control timer,
In addition, the opening and closing timing of the hot gas valve is controlled by the deicing completion detection temperature switch, and under conditions where the ambient temperature and the water supply temperature are high or medium, the water supply valve is opened and closed at the same time as deicing starts. Then, the hot gas valve opens, deicing is achieved in a short time, the deicing completion detection temperature switch is turned on, only the hot gas valve is closed, and the rise in the low pressure of the compressor stops at this point. .

The low pressure of this compressor rises rapidly as soon as deicing is completed, but since the hot gas valve is closed at the same time as deicing, the pressure does not rise suddenly. That is, as the temperature condition increases, the opening time of the hot gas valve becomes shorter, and as the temperature condition decreases, the opening time of the hot gas valve becomes longer.

In addition, under extremely low temperature conditions (below 10℃),
Since it is difficult to remove all the ice during the water supply time, after the timer for controlling the water supply valve has timed up, that is, after the set time limit has elapsed, deicing is performed using only hot gas, and the deicing completion detection temperature switch is activated. The hot gas valve is open until it is turned on, and remains open throughout the entire deicing process.

f. Embodiment Hereinafter, a preferred embodiment of the operation control device for an ice maker according to the present invention will be described in detail with reference to the drawings.
Fig. 2 shows an ice-making section 1c to which the operation control device according to the present invention can be applied, and the ice-making section 1c generally indicated by the reference numeral 1 is an ice-making plate made entirely of stainless steel plate and installed almost vertically. , this ice making plate 1
A tubular evaporator 2 is provided on the back surface 1a of the evaporator 2 to enable heat exchange. As shown in FIG. 2, the ice-making plate 1 is formed with a plurality of protrusions 3 hanging down at regular intervals, and the entire ice-making plate 1 is configured in a corrugated plate shape.
A plurality of ice-making surfaces 4 are provided at positions corresponding to the evaporator 2 on the surface 1b side of the ice-making plate 1 between the respective protrusions 3.
is formed, and semi-cylindrical ice particles 5 are formed on each ice making surface 4.
is formed.

A de-icing water sprinkling pipe 6 and an ice-making water sprinkling pipe 6a (shown in FIG. 3) are disposed above the ice-making plate 1.
This deicing water sprinkling pipe 6 is connected to a deicing water supply pipe (not shown) having a water supply valve 26 (to be described later), and can supply deicing water to the back surface 1a of the ice making plate 1 from its water sprinkling hole 6b. A circulation pump driven by a pump motor 22, which will be described later, is connected to the ice-making water sprinkling pipe 6a.

Furthermore, the configuration shown in FIG. 4 shows a refrigeration circuit of an ice maker to which the operation control device according to the present invention can be applied. , this compressor 8 is connected via a second conduit 9 to a condenser 10 having a fan motor 17 for cooling, and the condenser 10 is connected via a third conduit 11 to a capillary tube 12 which is an expansion means. has been done. The capillary tube 12 is connected to the upper end 2b of the evaporator 2 via the fourth conduit 13, and the temperature detection means 1 of the temperature-sensitive deicing completion detection temperature switch 18 is connected to the lower end 2a of the evaporator 2.
8' is installed. Branch portion 9 of second conduit 9
conduit 1 between a and the branch part 13a of the fourth conduit 13
4 is connected to a hot gas valve 15.

Next, the configuration shown in FIG. 1 includes a control circuit section 1 for sequentially controlling ice making and deicing processes.
9, and this control circuit section 19 is constituted by first to fifth circuits 30, 40, 50, 60, and 70.

Normally open contacts X ₄ and X ₅ for self-holding of the relay 20 are connected in series to a pump motor 22 provided in the first circuit 30 for circulating ice-making water.
The relay 20 of the second circuit 40 is a normally closed contact.
This relay 20 has a water level detection type ice making completion detection switch 21 provided in an ice making water tank (not shown ₎ and a normally open contact point X _{3 ,} X ₄ and X ₅ . Deicing completion detection temperature switch 18
The on contact 18a of the water supply valve and the normally open contact 25 of the water supply valve control timer 23 that control the water supply time are connected in series.

In the third circuit 50, the hot gas valve 15 connected to the normally closed contact _X2 is connected to the off contact 18b of the deicing completion detection temperature switch 18.

The water supply valve control timer 23 is connected in series to the normally closed contact X ₁ of the fourth circuit 60, and the normally closed contact 24 of the water supply valve control timer 23 is connected in series.
A series body consisting of water supply valves 26 connected in series is connected in parallel to the water supply valve control timer 23. Further, a fan motor 17 for the condenser 10 is connected in series to the normally open contact X ₃ of the fifth circuit 70, and the compressor 8 is connected in parallel to the fan motor 17.

In the above configuration, when the operation control device of the ice maker according to the present invention is operated, in the ice making process, the on-contact 18a
conducts, the relay 20 of the second circuit 40 is energized, and the normally open contacts X ₄ and X ₅ are closed, and the pump motor 22 is operated, causing ice to be made from the ice making water sprinkling pipe 6 a to the ice making surface 4 of the ice making plate 1. Water is supplied. At the same time, the fan motor 17 rotates to cool the condenser 10, and the compressor 8 operates to cool the ice making surface 4.
is cooled and ice particles 5 are formed.

At the same time as the growth of the ice grains 5 is completed, the ice making completion detection switch device 21 detects a decrease in the water level in the ice making tank (not shown) and is turned off, thereby detecting the completion of ice making. At the same time, the relay 20 is demagnetized and the normally closed contact X ₁ ,
X ₂ is turned on, normally _{open contacts X 3 ,} At the same time that deicing water is supplied to the evaporator 2, hot gas is supplied to the evaporator 2 to start the deicing process.

The control mode of this deicing process is significantly different when the ambient temperature and water supply temperature are high/medium temperature conditions (15°C or higher) and when they are low temperature conditions (less than 15°C). The control situation will be explained using the time charts shown in FIGS. 5A and 5B.

First, FIG. 5A shows the operation sequence of the deicing and ice making process under the above-mentioned high and medium temperature conditions, and the deicing completion detection temperature switch 18 is activated before and after the time _t1 when deicing is completed and ice making is started. The timer 23 for controlling the water supply valve is set to the deicing time _T1.
During this timer setting time, the water supply valve 2 is turned on.
6 and fan motor 17 are operated. The hot gas valve 15 is connected to the deicing completion detection temperature switch 18.
The valve remains open until the on-contact 18a is turned on (that is, until the completion of deicing is detected). This valve opening time P becomes shorter as the temperature condition becomes higher.

After the water supply valve control timer 23 times up, the ice making process is started, and the ice leaves the ice making surface 4 within the set time of the water supply valve control timer 23.

FIG. 5B shows the sequence when moving from the deicing process to the ice making process under low temperature conditions, and the water supply valve control timer 2 is activated at the same time as deicing starts.
3 is energized for a certain period of time, and the water supply valve 26 and fan motor 17 are operated during the set period of time. At the same time, the hot gas valve 15 is also opened. When the water supply valve control timer 23 times up, the water supply valve 26 and the fan motor 17 stop, but the hot gas valve 15 continues to open regardless of this time-up, and the temperature of the evaporator 2 rises. Until the completion of deicing is detected by the deicing completion detection temperature switch 18 (that is, until the on contact 18a becomes conductive)
The valve is opened and then the ice making process begins. in this case,
The lower the temperature condition is, the longer the deicing time _T5 using only hot gas becomes, but deicing is performed reliably.

g. Effects of the invention Since the ice maker operation control device according to the invention has the above configuration and function, the opening time of the hot gas valve in the deicing process can be changed depending on the ambient temperature and the water supply temperature. It can be controlled by a sequence program, prevents a sudden rise in low pressure, which is closely related to the load on the compressor, and reliably avoids overloading the compressor. Deicing can be performed reliably without any additional parts, and it can be assembled at a low cost without adding any parts. Furthermore, since a large diameter hot gas valve can be used, the deicing time is shortened and the ice making capacity is improved.

[Brief explanation of the drawing]

The drawings are for explaining the operation control device for an ice making machine according to the present invention. FIG. 1 is a circuit diagram showing the control circuit section, FIG. 2 is a schematic perspective view of the main parts of the ice making section, and FIG. Fig. 4 is a refrigeration circuit diagram of an ice maker to which the operation control device can be applied, and Fig. 5A is a partially enlarged cross-sectional view showing the ice making plate in Fig. 2. FIG. 5B is a time chart showing a state in which the control circuit section is operated in sequence. FIG. 5B is a time chart showing a state in which the control circuit section in FIG. 1 is operated in sequence under low ambient temperature or low water supply temperature conditions. 1 is an ice-making plate, 1c is an ice-making section, 2 is an evaporator, 4 is an ice-making surface, 5 is an ice grain, 6 is a de-icing water sprinkler pipe, 6a is an ice-making water sprinkler pipe, 8 is a compressor, 10 is a condenser, 12
is an expansion means (capillary), 15 is a hot gas valve, 17 is a fan motor, 18 is a deicing completion detection temperature switch, 19 is a control circuit section, 20 is a relay,
21 is an ice making completion detection switch, 22 is a pump motor, 23 is a water supply valve control timer, 24 is a normally closed contact, 25 is a normally open contact, and 26 is a water supply valve.

Claims (1)

[Scope of utility model registration request] A deicing completion detection temperature switch 18 is installed in the ice making section 1c having the evaporator 2 connected to the compressor 8 and detects the temperature of the ice making section 1c to detect the completion of deicing. Completion detection temperature switch 18
a hot gas valve 15 that is connected to the evaporator 2 and supplies hot gas to the evaporator 2; a water supply valve 26 that opens at the start of the deicing process to supply deicing water to the ice making section 1c; A water supply valve control timer 23 that starts a time-limited operation at the start of the deicing process and closes the water supply valve 26 when a set time limit has elapsed.
and a control circuit section 19 connected to the deicing completion detection temperature switch 18, the hot gas valve 15, the water supply valve 26, and the water supply valve control timer 23, and the set time limit of the water supply valve control timer 23 is ,
Although it is longer than the time it takes for the deicing completion detection temperature switch 18 to detect the completion of deicing under conditions of high or medium ambient temperature or high or medium supply water temperature, the time required for the deicing completion detection temperature switch 18 to detect the completion of deicing under conditions of low ambient temperature or low water supply temperature is longer. The time is set shorter than the time required to detect the completion of deicing, and the control circuit section 1
9, in the deicing process under conditions of high to medium ambient temperature or high to medium feed water temperature, the hot gas valve 15 is first closed, and then the water supply valve 26 is closed; An operation control device for an ice making machine, characterized in that in the ice process, the water supply valve 26 is closed first, and then the hot gas valve 15 is closed.