WO2006033141A1 - Freezing detection method for ice making apparatus and ice making apparatus - Google Patents

Abstract

A freezing detection method for an ice making apparatus capable of rapidly and accurately detecting freezing when the freezing occurs in a heat exchanger used when a supercooled water is made in a closed system. A bypass pipe is disposed between a water pipe positioned on the upstream side of the inlet of the heat exchanger for bringing water in a supercooled state and a communication pipe connecting the outlet of the heat exchanger to the inlet of a supercool releasing container. The tendency of the increase/decrease of flows per specified time measured by a first measuring device measuring the flow of the water flowing in the bypass pipe and a second measuring device measuring the flow of the water flowing in the water pipe is examined. Thus, the freezing of the heat exchanger can be detected.

Description

 Specification

 Freezing detection method for ice manufacturing apparatus and ice manufacturing apparatus

 Technical field

 [0001] The present invention relates to a heat exchanger that brings water to a supercooled state, a closed system releaser that releases supercooled water, and a connection that connects the outlet of the heat exchanger and the inlet of the releaser The present invention relates to a method of detecting freezing in an ice manufacturing apparatus having a tube, and an ice manufacturing apparatus capable of performing the method.

 Background art

 [0002] When freezing occurs in a heat exchanger that produces supercooled water, the flow rate in the heat exchanger is gradually blocked by ice, so the circulating flow rate decreases, and finally the circulating flow rate of water If it is left as it is, the heat exchange ^^ will be damaged. Therefore, in order to prevent an energetic situation, it is possible to avoid damage to the heat exchanger ^ by quickly capturing such changes in the flow rate and switching to freeze-release operation.

 [0003] In principle, this decrease in flow rate can be detected using only a flow meter that measures the total circulating water volume of the supercooled water. However, in practice, fluctuations in the flow rate occur constantly due to pump pressure fluctuations, inhomogeneous flow in the downstream piping, changes in the ice storage state in the heat storage tank, and switching of the downstream piping system. It is difficult to determine whether the detected flow fluctuation is due to freezing or other factors. For this reason, it is necessary to increase the threshold value of the flow rate fluctuation range in order to reliably recognize that the cause of the flow rate drop is due to freezing, but this has the problem that detection of freezing is delayed. Conversely, if the threshold value of the flow rate fluctuation range is reduced to increase the sensitivity, it will actually freeze and V (in other words) may start freeze-release operation (malfunction). A problem arises!

[0004] Conventionally, there are the following techniques for improving this. First, instead of detecting flow rate fluctuations, there is a force S that detects freezing by detecting pressure changes at the heat exchanger inlet (Patent Document 1). There are also proposals that use two independent methods (a method using a thermometer and a method using a flow meter) to determine freezing. (Patent Document 2). Patent Document 1: Japanese Patent Publication No. 6-300398

 Patent Document 2: Japanese Patent Publication No. 3087629

However, even if the freezing is detected by detecting the pressure change at the inlet of the heat exchange as in the technique disclosed in Japanese Patent Laid-Open No. 6-300398, It is difficult to determine instantly whether it is due to freezing or other factors. In the technology disclosed in Japanese Patent No. 3087629, the ice formation detection means first detects an abrupt temperature change from 2 ° C to 0 ° C, and the ice making detection means determines the start of the ice making operation. The supercooled water temperature sensor is calibrated based on the indicated value, and then the occurrence of freezing is detected when the supercooled water temperature sensor detects a sudden temperature change from 2 ° C to 0 ° C. ! / Speak.

 However, in this method, for example, if the ice making judgment means freezes in the heat exchanger before judging the start of the ice making operation, both the ice generation detection sensor and the cooling water temperature sensor have a 2 ° C force of 0 ° C. In order to detect a sudden temperature change, the freezing may be mistaken as the start of ice making operation.

 Disclosure of the invention

 Problems to be solved by the invention

[0006] The present invention has been made in view of the points to be worked on, and provides a technique for quickly and accurately detecting when freezing occurs in a heat exchanger for producing supercooled water. It is aimed.

 Means for solving the problem

[0007] In order to achieve the above object, in the present invention, a heat exchanger for bringing water into a supercooled state, a closed system releaser for releasing water in a supercooled state, and a supercooling water for the heat exchanger. An ice production apparatus having a connecting pipe connecting the outlet of the heat releaser and the inlet of the releaser, and providing a bypass pipe connecting the upstream pipe of the water inlet of the heat exchanger and the connecting pipe. RU Then, the flow rate or flow velocity of the water flowing through the upstream pipe and the flow rate or flow velocity of the water flowing through the bypass pipe are measured, and the flow rate or flow velocity of the upstream pipe obtained by the measurement is increased per predetermined time. Freezing in the heat exchanger is detected based on a decreasing trend and an increasing / decreasing trend of the flow rate or flow rate of water flowing through the bypass pipe per predetermined time. ing.

 [0008] During normal ice making or pre-cooling operation, the flow rate or flow rate of water flowing through the upstream pipe and bypass pipe of the heat exchanger water inlet is a certain value.

 However, when freezing occurs in the heat exchanger, the flow resistance between the inlet and outlet of the heat exchanger increases because the water flow path in the heat exchanger is blocked by the phase change. As a result, the flow rate or flow velocity of the water flowing through the upstream pipe of the connection with the bypass pipe in the upstream pipe tends to decrease. At this time, since the pressure difference at the inlet and outlet of the heat exchanger increases, the flow rate or flow velocity of the water flowing through the nopass pipe tends to increase. In this way, when the flow rate or flow velocity of water flowing through the pipe upstream of the heat exchange inlet decreases and the flow rate or flow velocity of water flowing through the bypass pipe increases, the fluctuations in flow rate and flow velocity are caused by freezing. It can be judged that.

 [0009] On the other hand, in the case of flow rate fluctuations and flow rate fluctuations due to factors other than freezing of the heat exchanger, the flow rate or flow rate of water flowing through the upstream pipe and the flow rate or flow speed of water flowing through the bypass pipe both decrease. It shows a tendency or both show an increasing tendency. Furthermore, if the flow rate or flow velocity of the water flowing through the pipe upstream of the heat exchanger ^^ increases and the flow rate or flow velocity of the water flowing through the bypass pipe decreases, it can be determined that the non-pass piping is clogged. .

 Therefore, as in the present invention, the flow rate or flow rate of water flowing through the upstream pipe and the flow rate or flow rate of water flowing through the bypass pipe are measured, and the upstream pipe obtained by the measurement is measured. Freezing in the heat exchanger is detected by examining the increasing / decreasing tendency of the flow rate or flow rate of water per predetermined time and the increasing / decreasing trend of the flow rate or flow rate of water flowing through the bypass pipe per predetermined time. It becomes possible. In addition, according to the present invention, even when the operation is performed by changing the water circulation flow rate, it is possible to accurately determine freezing without changing the set value. Furthermore, errors in the flow meter and velocimeter (systematic error) do not affect the determination of freezing.

The flow rate and flow velocity of the upstream pipe may be measured on the upstream or downstream side of the connection with the bypass pipe in the upstream pipe. However, in the actual construction, considering the degree of freedom in the installation location, a device for measuring the flow rate and flow velocity is installed on the upstream side of the upstream pipe connection with the bypass pipe. In side piping It is better to measure the flow velocity and flow rate of the water flowing through the pipe upstream of the connection with the bypass pipe.

 [0011] When a flow meter is used to measure the flow rate and the increase / decrease trend is examined, the flow meter has a “resolution” with respect to the full scale. In the present invention, the increase / decrease trend per predetermined time is shown. Since it was made to check, it is only necessary to compare the measured value after a predetermined time, for example, 10 seconds after the first measurement, with the first measured value, and investigate the increase or decrease in the current time. Speaking of the resolution, if the flow rate is measured at a predetermined time, for example, every 10 seconds, for example, if a flow meter with a resolution of 1% is used, a full-scale lZio

If there is an increase or decrease in the flow rate of about 0, it may be determined as “increase or decrease” in the present invention.

[0012] It should be noted that the measurement object may be either the flow rate or the flow rate of the water flowing through the pipe upstream of the connection with the bypass pipe in the upstream pipe and the water flowing through the bypass pipe. Either one may be a flow rate and the other one may be a flow rate.

 [0013] Furthermore, since the flow rate and flow velocity of the water flowing in the bypass pipe are determined by the differential pressure of heat exchange, the flow rate and flow velocity of the water flowing in the upstream pipe are set to a certain fixed value. If the flow rate and flow rate of the water flowing in the bypass pipe are monitored, the flow rate and flow speed of the water flowing in the bypass pipe increase as the heat exchange becomes dirty. This also makes it possible to measure heat exchange contamination.

 [0014] When the connection pipe is provided with a propagation preventing means for preventing the supercooling release from propagating from the releaser to the heat exchanger side, the bypass pipe is located upstream of the inlet of the heat exchanger. It is preferable that the pipe is connected to the upstream side of the propagation preventing means in the connecting pipe. Alternatively, the propagation preventing means may be connected as in the embodiment described later. The upstream side of the propagation prevention means is a place where supercooled water that does not undergo phase change flows. Thus, in normal ice making operation, the phase change does not occur and the heat exchange ^^ This is because by connecting the water pipe with a bypass pipe, it is possible to prevent the phase change in the subcooler from causing disturbance to the measurement of flow rate and flow velocity, and to realize more accurate detection of freezing. .

[0015] Further, without using a bypass pipe as described above, each pressure at the inlet and outlet of the water in the heat exchanger ^ is measured, and each pressure obtained by the measurement is increased and decreased per predetermined time. It is also possible to detect freezing in the heat exchanger based on the direction.

 [0016] That is, when freezing occurs in the heat exchanger, the flow path of water in the heat exchanger is blocked by the phase change, and the flow resistance between the heat exchanger inlet and outlet increases. Measure the pressure at the water inlet and outlet of the heat exchanger, and if the pressure at the heat exchanger inlet tends to increase and the pressure at the heat exchanger outlet tends to decrease, the pressure fluctuations It can be judged that it was caused by freezing of the vessel.

 [0017] If the pressure at the heat exchanger outlet is both increasing and decreasing, the pressure fluctuation is judged to be based on factors other than freezing, and the pressure at the heat exchanger tends to decrease. When the pressure at the outlet of the heat exchanger tends to increase, it can be determined that there is an abnormality in the pressure gauge that measured the pressure, or pressure fluctuations caused by backflow.

 Note that the connecting pipe in the present invention may not be a straight pipe, and may be partly divided as described later, for example.

 [0018] Further, according to the present invention, a heat exchanger that brings water into a supercooled state, a closed system releaser that releases supercooled water, an outlet of the supercooled water of the heat exchanger, and the release In an ice manufacturing apparatus having a connecting pipe connecting to the inlet of the heat exchanger, a bypass pipe connecting the external container that covers the outer periphery of the connecting pipe in a water-tight manner and the upstream pipe at the inlet of the heat exchanger. And a first measuring device for measuring a flow rate or a flow velocity of water flowing in a pipe upstream of a connection portion of the upstream pipe with a bypass pipe, and a first measuring device for measuring a flow rate or a flow speed of water flowing in the bypass pipe. There is also provided an ice manufacturing apparatus, characterized in that the connecting pipe is divided over the entire circumference through a gap in the outer container.

[0019] In the ice making device of the present invention having a powerful structure, water of 0 ° C or higher flowing through the bypass pipe upstream of the inlet of the heat exchanger ^^ is supplied to the entire inner wall surface of the connecting pipe. Then, a liquid film of water of 0 ° C or higher is formed on the entire inner wall surface of the connecting pipe downstream from the supplied part. This liquid film prevents ice from adhering to the inner wall of the connecting pipe and propagating upstream of the phase change. Also, inside the liquid film of 0 ° C or higher formed on the wall surface, even if ice nuclei exist, it does not grow, but eventually melts or flows downstream, so that phase change occurs in the connecting pipe. Supplying water of more than o ° c will not propagate upstream. [0020] Then, the first measuring device for measuring the flow rate or flow velocity of the water flowing through the pipe upstream of the connecting portion with the bypass pipe in the upstream pipe, and the flow rate or flow velocity of the water flowing through the bypass pipe are measured. The increase or decrease tendency of the water flow rate or flow velocity of the upstream pipe obtained by the measurement of the second measuring device per predetermined time and the increase or decrease tendency of the flow rate or flow velocity of the water flowing through the bypass pipe per predetermined time are shown. By examining it, it becomes possible to detect freezing in the heat exchanger by the judgment method described above.

 The invention's effect

 [0021] According to the present invention, when freezing occurs in a heat exchanger for producing supercooled water, it can be detected quickly and accurately. In addition, since the judgment is based on the flow rate, flow velocity, or pressure increasing / decreasing tendency of the two power stations, accurate freezing judgment can be made without changing the set value, etc., even if the water circulation flow rate is changed. . Furthermore, even if there is an error (systematic error) in the flowmeter, flowmeter, or pressure gauge used to measure the flow rate, flow velocity, or pressure, it does not affect the determination of freezing.

 Brief Description of Drawings

[0022] FIG. 1 is an explanatory diagram showing a system of an ice manufacturing apparatus that works on the first embodiment.

 FIG. 2 is an explanatory view showing a system of an ice manufacturing apparatus that works on the second embodiment.

 FIG. 3 is an explanatory diagram showing a system of an ice manufacturing apparatus that works on the third embodiment.

 FIG. 4 is an explanatory view showing an internal state of a communication pipe of an ice making device that works according to a third embodiment.

 FIG. 5 is a table showing measurement results of Examples.

 Explanation of symbols

[0023] 1, 51, 61 Ice making equipment

 2 Heat exchanger

 4 Water piping

 14 Connecting pipe

 15 Subcooler

 16 Propagation prevention measures

31, 64 32 First measuring device

 33 Second measuring device

 BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Fig. 1 shows the outline of the ice manufacturing device 1 that works in this embodiment. Heat exchange 2 performs heat exchange between the brine flowing in the brine transport pipe 3 and the water flowing in the water pipe 4. It has the function of turning the water into supercooled water below ° C. In the brine transfer pipe 3, for example, brine of a predetermined temperature from the brine cooling means 5 such as a refrigerator flows by the brine pump 6 and circulates between the heat exchanger 2 and the brine cooling means 5. Various types of heat exchangers such as plate type and shell and tube type can be used for heat exchange 2.

 [0025] Water taken from the ice heat storage tank 11 flows through the water pipe 4, and is heated to 0 ° C or higher, for example, about 0.5 ° C by the preheating means 12, and then heated by the water pump 13. Sent to Exchanger 2. Examples of the preheating means include an electric heater, a condenser of a refrigerator, and a heat exchange using the heat of the cooling water exiting the refrigerator. After heat is generated in subcooling water at 2 ° C or less in heat exchange 2, the connecting pipe 14 (the heat exchanger for supercooling and the supercooling release unit are connected, more specifically, for supercooling The outlet part of the heat exchanger and the inlet part of the supercooling releaser are connected to each other and sent to the closed supercooling releaser 15 where sherbet-like ice is produced. Supercooling release unit used in the present embodiment

15 has the function of releasing the supercooled state of the supercooled water that has flowed in through the connecting pipe 14, changing the phase to generate slurry-like ice, and discharging it to the outside. As a trigger for canceling the supercooling, for example, an ultrasonic wave from an ultrasonic transducer is used, and a known one can be used as appropriate for this type of hermetic releaser 15.

[0026] The connecting pipe 14 is provided with a propagation preventing means 16 for preventing the freezing from propagating to the heat exchanger 2 side. As the propagation preventing means 16, in addition to the so-called split type connecting pipe described later, a propagation preventing part is configured with a straight pipe as disclosed in, for example, Japanese Patent Publication No. 2001-241705, and supercooling is performed. It can be proposed to circulate the supercooled water at a water flow rate of 4mZs or higher. [0027] The sherbet-shaped ice produced by the supercooling release unit 15 is sent to the secondary load 22 through the transfer pipe 21, and is sent to the ice heat storage tank 11 after the load treatment. The transfer pipe 21 is connected to a transfer pipe 23 that directly communicates with the ice heat storage tank 11 and is not loaded with the secondary load 22. The ice is sent directly to the ice storage tank 11, where it is subjected to ice storage operation. The transfer pipes 21 and 23 are provided with corresponding flow rate adjusting valves 24 and 25, respectively, and the main pipes of the transfer pipes 21 and 23 are pumps that push sheave-shaped ice into the pipes. (Not shown) is provided.

 [0028] Between the water pipe 4 and the connecting pipe 14 on the upstream side of the inlet of the heat exchanger 2, a binos pipe 31 that bypasses the heat exchanger 2 is provided. In the present embodiment, the connection portion between the bypass pipe 31 and the connecting pipe 14 is set on the upstream side of the propagation preventing means 16 in the connecting pipe 14.

 [0029] The bypass pipe 31 is provided with a first measuring device 32, such as a flow meter, for measuring the flow rate of water flowing in the bypass pipe 31, and upstream of the connection with the bypass pipe 31 in the water pipe 4. On the side, a second measuring device 33, such as a flow meter, is installed to measure the flow rate of water flowing through the water pipe 4.

[0030] The ice manufacturing apparatus 1 according to the present embodiment has the above-described configuration, and the detection of the freezing of the heat exchanger 2 is detected by the first measuring device 32 and the second measuring device 33. Based on the trend of increase and decrease in the predetermined time, the following judgment is made.

 That is,

 Increase in the flow rate of the first measuring device 32, increase in the flow rate of the second measuring device 33 → Flow rate fluctuations other than freezing

 Reduced flow rate of first measuring device 32, decreased flow rate of second measuring device 33 → Flow rate fluctuations other than freezing

 Increase in flow rate of the first measurement device 32, decrease in flow rate of the second measurement device 33 → Freezing Decrease in flow rate of the first measurement device 32, increase in flow rate of the second measurement device 33 → Clogging of the bypass pipe 3 1

It is. The predetermined time here refers to the interval at which the flow rate is measured. For the purposes of the invention, the shorter the time, the faster the detection. For example, one with a length of about 10 seconds per second can be proposed [0031] In the above embodiment, the first measuring device 32 and the second measuring device 33 both use a flow meter for measuring the flow rate, but either one or both may be used for the flow of water in the pipe. An anemometer that measures the speed may be used. The judgment at that time is the same as in the case of the above flow meter, and the same judgment method can be followed instead of the flow rate instead of the flow velocity.

 Next, a second embodiment will be described. FIG. 2 shows an outline of an ice making device 51 that can be used in the second embodiment. The members and devices indicated by the same reference numerals shown in FIG. 1 are the same as those in the first embodiment. The same members and devices as those of the ice making device 1 are shown. The ice manufacturing device 51 according to the second embodiment is not provided with the bypass pipe 31 in the ice manufacturing device 1 according to the first embodiment, and the first pressure measuring device is provided on the inlet side of the heat exchange 2. 52. The second pressure measuring device 53 is provided on the outlet side of the heat exchanger 2.

 [0033] According to the ice making device 51 having a powerful configuration, the detection of the freezing of the heat exchange 2 is based on the increasing and decreasing tendency of the first pressure measuring device 52 and the second pressure measuring device 53 over a predetermined time. The following judgment is made.

 Pressure rise of first pressure measuring device 52, pressure rise of second pressure measuring device 53 → Pressure fluctuation other than freezing

 Pressure drop of the first pressure measuring device 52, pressure drop of the second pressure measuring device 53 → pressure fluctuation other than freezing

 Pressure increase of first pressure measuring device 52, pressure drop of second pressure measuring device 53 → Freezing

 Pressure drop of the first pressure measuring device 52, pressure rise of the second pressure measuring device 53 → Abnormal or reverse flow of the pressure measuring device

 It is.

 [0034] Thus, according to the ice making device 51 that works well in the second embodiment, the pressure at the inlet / outlet of the heat exchanger ^^ 2 is increased! ] Based on the decreasing trend, the freezing of the heat exchanger 2 can be detected quickly and accurately. However, since it is not necessary to install a no-pass pipe, it is only necessary to install pressure gauges at two force points for the existing equipment.

Next, a third embodiment will be described. Figure 3 shows an example of ice In this embodiment, a heat exchanger for generating supercooled water has a supercooler 62 having a so-called shell “and” tube configuration. .

 [0036] One end of the connecting pipe 14 is connected to the outlet side of the supercooler 62, that is, the discharge port 63 with a reduced diameter, and the other end of the connecting pipe 14 is connected to the hermetic supercooler 15. It is connected to the. One end of a no-pass pipe 64 is connected to the downstream side of the water pump 13 in the water pipe 4, and the other end is connected to an external container 65 that covers the outer periphery of the connecting pipe 14 in a water-tight manner. .

 [0037] As shown in Fig. 4, the connecting pipe 14 is divided at right angles to the axial direction so as to create a gap d in the outer container 65, and is connected to the upstream connecting pipe 14a and the downstream connecting pipe 14b. It is divided into Therefore, when water is fed from the bypass pipe 64 into the outer container 65, the water that has entered the connecting pipe 14 also flows into the connecting pipe 14 along the flow in the connecting pipe 14 and flows downstream along the wall surface of the downstream connecting pipe 14b. A film of water injected into the wall of the downstream connecting pipe 14b is formed. Since the pressure applied to the water flowing through the binos pipe 64 by the water pump 13 is maintained up to the outer container 65, there is no problem in pushing the water into the connecting pipe 3 from the gap d! /.

 [0038] The first measuring device 32 is provided on the upstream side of the connecting portion of the water pipe 4 with the nopass pipe 64, and the second measuring device 33 is provided on the bypass pipe 64.

 [0039] The ice making device 61 that works in the third embodiment has the above-described configuration. By the same method as the ice making device 1 according to the first embodiment described above, The freezing of the subcooler 62 can be detected based on the increasing and decreasing trend of the flow rate by the first measuring device 32 and the increasing and decreasing trend of the flow rate by the second measuring device 33.

[0040] According to the ice making device 61 according to the third embodiment, the external container 65 is formed by the combination of the bypass pipe 64 and the external container 65 installed for determining whether the supercooler 62 is frozen. It also functions as a propagation preventing means. That is, for example, when water at 0 ° C is taken from the heat storage tank 11, the temperature is raised to 0.5 ° C by the preheater 12. This 0.5 ° C water is cooled in the supercooler 62 to a supercooling state of -2 ° C, for example, and sent to the supercooler 15 via the connecting pipe 14 as it is. For example, if the supercooling state is released, In this case, o ° c slurry-like ice is produced and continuously discharged to the outside.

 [0041] On the other hand, 0.5 ° C water branched from the water pipe 4 and flowing into the bypass pipe 64 is poured into the outer container 65, and from the divided portion of the connecting pipe 14, that is, from the gap d, the connecting pipe 14 It enters the interior and flows downstream along the flow of supercooled water. At this time, since the gap d extends over the entire circumference, the water at 0.5 ° C flows along the wall surface of the inner wall of the downstream connecting pipe 14b. A liquid film of 5 ° C water is formed. The junction point between the bypass pipe 64 and the outer vessel 65 (water injection Z receiving opening) is set with a predetermined distance from the gap d by shifting the axis. This is a configuration for uniformly injecting water from the entire wall surface.

 [0042] Therefore, even if the supercooling release performed in the supercooling releaser 15 is to propagate upstream along the wall surface, a liquid film of 0 ° C or higher is formed on the inner wall surface of the downstream connecting pipe 14b. Therefore, propagation to the upstream side, that is, propagation to the subcooler 62 is prevented. Also, inside the liquid film of 0 ° C or higher formed on the wall surface, it will not grow even if ice nuclei are present, and will eventually melt or be flowed downstream by the flow of supercooled water. Therefore, the phase change does not propagate upstream beyond the outlet of the connecting pipe 14. Therefore, freezing at the outlet of the connecting pipe 14 and the supercooler 62 is prevented, and stable slurry-like ice can be produced continuously.

 [0043] The method for cooling the water flowing in the heat exchanger for supercooling is not limited. For example, cooling may be performed by evaporating the refrigerant without using the brine.

 [0044] (Example)

Next, the result of the inventor actually performing the freeze detection method according to the present invention will be described. The basic configuration of the system is shown in Fig. 1, and we decided to measure and detect the flow rates of bypass pipe 31 and water pipe 4. The flowmeter of the first measuring device 32 used in this experiment has a full scale of 100 [lZmin] and a resolution of l% [llZmin], and the flowmeter of the second measuring device 33 has a full scale of 2000 [lZmin]. ] With a resolution of 0.3% [61 / min]. The measurement interval was 10 seconds (0.166 minutes). Therefore, if the absolute value of the product AXB of each flow rate deviation is less than 6, this is not a significant change. That is, I AX BI ≥1 X 6 = 6.

 Therefore, in this experiment, the determination of freezing was made so that I A X B | In other words, when the value of I AX B I was 15 or more, it was determined that the product was frozen. In principle, as described above, the value of I AX B I may be 6 or more.

 [0045] The measurement results are shown in the table of FIG. The data judged to be frozen are indicated by “*” in the table, and the data from the start of measurement until 222.0 minutes are omitted for convenience of drawing. As a result, it was judged that it was frozen after 223.5 minutes from the measurement so that the force was weak, and when it was examined, it was found that heat exchange 2 was actually frozen. Prior to this time, the above criteria for freezing were not met, and heat exchange 2 actually did not freeze. Therefore, it was confirmed that the present invention can make a quick and accurate determination of freezing. Industrial applicability

[0046] In the present invention, when freezing occurs in a heat exchanger that produces supercooled water, it can be detected quickly and accurately. Therefore, when the supercooled water is produced using heat exchange, Can be operated safely, and damage to the equipment can be prevented. Therefore, ice making operation can be performed safely, and it is extremely useful in the field of air conditioning using ice heat storage, for example.

Claims

The scope of the claims  [1] A heat exchanger that brings water to a supercooled state, a closed system releaser that releases supercooled water, and a connection that connects the outlet of the heat exchanger's supercooled water and the releaser In an ice manufacturing device having a tube,  A bypass pipe connecting the upstream pipe of the heat exchange water inlet and the connecting pipe is provided, and the flow rate or flow rate of water flowing through the upstream pipe and the flow rate or flow rate of water flowing through the bypass pipe are measured. And  Based on the trend of increasing or decreasing the flow rate or flow rate of water in the upstream pipe per predetermined time obtained by the measurement and the increasing or decreasing trend of the flow rate or flow rate of water flowing through the bypass pipe per predetermined time, A method for detecting freezing in an ice making device, characterized by detecting freezing in heat exchangers.  [2] In the method for detecting freezing of the ice manufacturing device according to claim 1,!  When the connection pipe is provided with a propagation preventing means for preventing the supercooling release from propagating from the releaser to the heat exchanger side, the bypass pipe is located upstream of the inlet of the heat exchanger. A pipe is connected to connect the upstream side of the propagation preventing means in the connecting pipe or the propagation preventing means.  [3] a heat exchanger that brings water to a supercooled state, a closed system releaser that releases supercooled water, and a connection that connects the outlet of the heat exchanger's supercooled water and the releaser In an ice manufacturing device having a tube,  Measure the pressure at the inlet and outlet of the heat exchanger ^^  A freezing detection method for an ice production apparatus, wherein freezing in the heat exchanger is detected based on a tendency of increase and decrease of each pressure per predetermined time obtained by the measurement. [4] a heat exchanger that brings water into a supercooled state, a closed system releaser that releases supercooled water, and a connection that connects the outlet of the heat exchanger's supercooled water and the releaser In an ice manufacturing device having a tube,  A bypass pipe connecting the upstream pipe of the inlet of the heat exchanger and the connecting pipe; A first measuring device for measuring a flow rate or a flow velocity of water flowing in the upstream pipe, a second measuring device for measuring a flow rate or a flow velocity of water flowing in the bypass pipe, An ice manufacturing apparatus characterized by comprising: [5] In the ice making device according to claim 4,  Propagation preventing means for preventing the supercooling release from propagating from the releaser to the heat exchanger side is provided in the connecting pipe,  The bypass pipe is piped so as to connect an upstream pipe at the inlet of the heat exchanger and an upstream side of the propagation preventing means in the connecting pipe or the propagation preventing means. [6] a heat exchanger that brings water to a supercooled state, a closed system releaser that releases supercooled water, and a connection that connects the outlet of the heat exchanger's supercooled water and the releaser In an ice manufacturing device having a tube,  A first pressure measuring device for measuring the pressure at the inlet of the heat exchanger;  A second pressure measuring device for measuring the pressure at the outlet of the heat exchanger;  An ice manufacturing apparatus characterized by comprising: [7] a heat exchanger that brings water into a supercooled state, a closed system releaser that releases supercooled water, and a connection that connects the outlet of the heat exchanger to the releaser In an ice manufacturing device having a tube,  An external container that covers the outer periphery of the connecting pipe in a water-tight manner, and a bypass pipe that connects the inside of the external container and the upstream pipe of the inlet of the heat exchanger;  A first measuring device for measuring the flow rate or flow velocity of the water flowing in the upstream pipe, and a second measuring device for measuring the flow rate or flow velocity of the water flowing in the bypass pipe, and in the external container, The ice production apparatus, wherein the connecting pipe is divided over the entire circumference through a gap.