JP2000074532A - Icemaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate an unevenness of an operating effect caused by a machin ing accuracy of a small bore tube, damage of a surface or a difference of ther mal conductivity and heat capacity by cutting a downstream side end inside the small bore tube in a tapered state, and preventing a phase change propaga tion from a large bore tube into the small bore tube. SOLUTION: Supercooled water 10 generated in a cooler 1 is accelerated via a small bore tube 4 so that a flowing velocity in the tube becomes 2.7 m/sec or more, and injected in a large bore tube 5. The injected supercooled water 10 changes the water of an amount corresponding to a supercooling degree to ice by an ice nucleus generated by a phase change inducing unit 7 installed on an outer periphery of the tube 5, and the water 10 is converted to a mixture of the water and the ice. At this time, in the case that an inner surface of the downstream side end of the tube 4 is cut in a tapered state, the ice is grown in the state that the ice is floated from a tapered surface, and hence the grown ice in blown away by the injecting velocity of the water 10 to prevent phase change propagation to the inner surface of the tube 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ice manufacturing system for storing ice for heat storage as a cold heat source for air conditioning, ice for scattering at indoor and outdoor ski resorts, and ice for general cooling and cooling. The present invention relates to an apparatus for continuously and stably producing ice in a closed pipe using cooling water.

[0002]

2. Description of the Related Art Conventionally, a supercooled water obtained by cooling water to 0 ° C. or lower has a flocculent (sherbet-like /
Examples of an apparatus for producing liquid-like ice include, for example, JP-A-62-147271, JP-A-63-14063,
JP-A-63-21463, JP-A-1-114682
And JP-A-3-241251 are known. In these devices, the supercooled water immediately after flowing out of the cooling pipe of the cooler is released and dropped into the atmosphere, and collides with a shock plate installed below to eliminate the supercooled state and remove the sherbet-like ice. Has been generated.

Further, as disclosed in JP-A-6-123455 and JP-A-6-123456, supercooled water released to the atmosphere is received by a vertical pipe called a release pipe, and the supercooled state is eliminated in the release pipe. There is a method of transferring the generated sherbet-like ice to a heat storage tank by piping.

However, in these systems, (1) a certain vertical distance or more is required between the cooler and the impact plate or the release pipe, and the height at which the apparatus is installed is limited. A vertical distance equal to or greater than a certain level occurs between the heat storage tank that stores the collected ice and the cooler. (3) Heat release with the atmosphere occurs because it is once released to the atmosphere.
Part of the generated ice melts. (4) Since ice storage and ice transportation are performed due to free fall and water level difference, it is difficult to transport the generated ice to a distant place.

There is also a system in which the generated supercooled water is conveyed to the heat storage tank in a supercooled state to the heat storage tank. However, if the supercooled state is eliminated at an unexpected place in the pipe and ice is generated. The phase change propagates to the upstream side even if the pipe is clogged or not clogged with the generated ice, and the cooler freezes when it reaches the cooler, making continuous operation impossible. Therefore, in order to prevent the supercooled state from being eliminated in the transport piping,
Although the operation is performed in a state where the supercooling water is not easily resolved by raising the temperature of the supercooling water, if the supercooling temperature is high, the amount of ice generated per There is a problem that the power of the circulation pump for circulation is increased.

Accordingly, the present inventors have proposed an apparatus for continuously converting supercooled water obtained by previously cooling water to 0 ° C. or lower into sherbet ice in a closed pipe as disclosed in Japanese Patent Application Laid-Open No. 7-4.
No. 801 and Japanese Patent Application Laid-Open No. H8-110133 have proposed an ice making apparatus. With these devices, the sherbet ice generated from the supercooled water can be pumped by a pipe, and a supercooled ice manufacturing device having no height and space limitation can be realized.

However, as disclosed in Japanese Patent Application Laid-Open No. 8-110133, the vertical disk portion connecting the large-diameter pipe and the small-diameter pipe constituting the supercooling elimination section is heated to prevent the accumulation of ice and to reduce the diameter of the small-diameter pipe. A method of preventing propagation of a phase change into a pipe, or a method of directly heating a pipe through which supercooled water flows as in Japanese Patent Application Laid-Open No. 5-149653, to change a phase from a downstream side where ice exists to an upstream side in a supercooled state. Although the method of directly preventing propagation has a difference in the heating method, there are problems such as the necessity of a heat source and energy for heating and the complicated device.

In Japanese Patent Application Laid-Open No. 7-4801, a phase change from supercooled water to ice is prevented from propagating upstream without using heating means. A small diameter pipe (nozzle)
It has been found that the effect varies depending on the material (especially the value of the heat conductivity and heat capacity inherent to the material) and the processing accuracy of the nozzle surface. The present invention is a further improvement of the above-mentioned prior application.

[0009]

SUMMARY OF THE INVENTION A basic object of the present invention is to produce ice continuously in a closed pipe using supercooled water. It is an object of the present invention to provide an ice manufacturing apparatus capable of preventing a phase change to be propagated to an upstream side. Another object of the present invention is to enable an ice producing apparatus to exhibit stable performance with no variation in its operation and effect.

[0010]

The basic structure of an ice making apparatus according to the present invention is the same as that of the above-mentioned prior application, and includes a cooler for cooling water to produce supercooled water, and a supercooled water generated. A supercooling release device for eliminating the supercooled state of the water and continuously converting the mixture into a mixture of water and ice, wherein the supercooling device is connected so that water and ice flowing therethrough do not come into contact with the atmosphere; The release device includes a small-diameter pipe and a large-diameter pipe, and the inlet side of the supercooled water is made of a small-diameter pipe so that the flow velocity in the pipe becomes 2.7 m / s or more, and a downstream end of the small-diameter pipe. A large-diameter pipe is fixed to an edge of the large-diameter pipe via a vertical disk, and a phase change inducing device that induces a phase change from supercooled water to ice is provided on an outer periphery of the large-diameter pipe. In the first aspect of the present invention, the inside of the downstream end of the small diameter pipe is tapered so as to prevent the phase change propagation from inside the large diameter pipe to the inside of the small diameter pipe. It is characterized by points.

[0011]

In the present invention, the prevention of phase change propagation from ice generated in a large diameter pipe to the upstream is performed as follows.
Generally, ice generated from supercooled water has a plate-like or needle-like structure, and when the supercooled water contacts the crystal, the ice grows straight in the crystal direction. In other words, the propagation of the phase change on the wall surface does not mean that the water grows upstream while sticking to the wall surface like hard ice, which is cooled without supercooling and frozen on the cooling surface, Since the plate-like and needle-like fine crystals themselves grow by the cool heat from the supercooled water, the adhesion to the tube wall is weak. When the pipe wall surface to which ice adheres is made of a material having a small heat capacity and heat conduction such as resin, the ice has a weaker adhesive force and is more likely to be blown off by a water flow.

When the inner surface of the downstream end of the small-diameter pipe is cut in a tapered shape as in the present invention, propagation from the periphery of the small-diameter pipe to the inside of the small-diameter pipe is such that a phase change propagates along the tapered surface. Instead, the ice grows in the direction of the ice crystal,
Ice grows from the tapered surface with the ice floating. Therefore, the ice grown by the jet velocity of the supercooled water is blown off, and the phase change does not propagate to the inner surface of the small-diameter pipe.

According to the second aspect of the present invention, in the second aspect, the small-diameter pipe is disposed in a large-diameter pipe so as to protrude in a nozzle shape, and supercooled water is supplied to the large-diameter pipe downstream of the nozzle-shaped portion. In a type of ice manufacturing apparatus provided with a phase change inducing device that induces a phase change from ash to ice, the same operation and effect can be achieved by providing similar features.

According to a preferred aspect of the present invention, the small-diameter pipe has an inner surface covered with a resin-based lining material having a small heat capacity. According to another preferred aspect of the present invention, the small-diameter pipe projecting in a nozzle shape has an inner surface and / or an outer surface covered with a resin-based lining material having a small heat capacity, or the entire small-diameter pipe has a small heat capacity. It is formed of resin. According to still another preferred aspect of the present invention, a bypass pipe for circulating and flowing water and ice from around the downstream end of the large-diameter pipe to a portion protruding in a nozzle shape of the small-diameter pipe is provided. It is connected. According to still another preferred aspect of the present invention, a bypass pipe branched from an upstream pipe of a cooler that generates supercooled water is connected near an upstream end of the large-diameter pipe. According to these preferred embodiments, the effect that the phase change does not propagate from the inside of the large-diameter tube to the inner surface of the small-diameter tube is further enhanced. Hereinafter, the configuration, operation, and effects of the present invention will be described in detail with reference to the accompanying drawings.

[0015]

FIG. 1 shows an entire ice making system (primary side) including an ice making apparatus using supercooled water according to a preferred embodiment of the present invention. Water from an ice storage tank 8 is introduced into the cooler 1 by a water circulation pump 9, and the water passing through the inside of the cooler 1 is cooled to a temperature below freezing (supercooling). A refrigerator 2 is used for cooling water, and brine (non-freezing liquid) is supplied to the refrigerator 2 by a brine circulation pump 3. The water 10 that has reached supercooling is sent from the small-diameter pipe 4 to the large-diameter pipe 5. The supercooling canceling device 23 includes a small-diameter pipe 4, a large-diameter pipe 5, and a well-known phase-change-inducing device (such as cavitation generated by a rotating body or an ultrasonic vibrator, or collision from friction or solids between water and ice). Device 7 for inducing a phase change to).

The supercooled water 10 generated by the cooler 1 is accelerated by the small-diameter pipe 4 so that the flow velocity in the pipe becomes 2.7 m / s or more, and is jetted into the large-diameter pipe 5. The supercooled water 10 spouted into the large-diameter pipe 5 is caused by ice nuclei generated by the phase change inducing device 7 installed on the outer periphery of the large-diameter pipe 5.
The supercooled state is eliminated, and water corresponding to the degree of supercooling changes to ice, and the supercooled water becomes a mixture of water and ice.

Thereafter, the ice becomes an ice nucleus and a phase change from supercooled water to ice occurs continuously. At this time, the phase change from supercooled water to ice generated in the large-diameter pipe 5 also advances to the upstream (in the small-diameter pipe 4). Since the temperature of the supercooled water 10 jetted from the small-diameter pipe 4 into the large-diameter pipe 5 is equal to or lower than the freezing temperature of the water, the temperature around the inner wall surface of the small-diameter pipe 4 and the supercooled water spout of the small-diameter pipe 4 is reduced. The pipe wall surface is cooled below the freezing temperature by heat conduction or heat transfer from the supercooled water.

FIGS. 2A to 2E show a state in which the phase change from supercooled water to ice tends to progress to the upstream side. FIG. 2A,
As shown in B, when ice is generated in the large-diameter tube 5, the ice adheres and accumulates on the cooled wall surface. When the supercooled water comes into contact with the ice adhered to the wall surface, the ice grows and a phase change progresses toward the small diameter pipe 4 along the wall surface. When the ice 13 deposited near the end of the small-diameter tube 4 grows to the end of the small-diameter tube 4, a phase change tends to propagate inside the small-diameter tube 4.

When the small-diameter tube 4 and the vertical disk 15 connecting the small-diameter tube 4 and the large-diameter tube 5 are made of a material having a small heat capacity and heat conduction, such as a resin, the flow velocity is 2.7 m / s or more. The ice that is going to propagate inside is blown off by the supercooled water blown out in the step, and is not easily propagated inside the small diameter pipe. However, since the ice attached near the outlet of the small-diameter pipe remains without being blown away, the phase change is always going to propagate inside the small-diameter pipe, and the downstream end of the small-diameter pipe 4 as shown in FIGS. 2A and 2B. If the inside is not cut in a tapered shape, when the water flow inside the large diameter pipe 5 is disturbed and the supercooled water flow rate fluctuates, a phase change propagates to the inner surface of the small diameter pipe 4.

On the other hand, in the case of FIGS. 2C and 2D in which the inside of the downstream end of the small diameter pipe 4 is cut in a tapered shape according to the present invention, in order for the phase change to progress in the small diameter pipe 4, the tapered surface is required. Although ice needs to grow along 14, the ice generated from the supercooled water 10 has a plate-like or needle-like structure,
When supercooled water comes into contact with the crystal, ice grows straight in the direction of the crystal. In other words, the propagation of the phase change on the wall surface does not mean that the water grows upstream while sticking to the wall surface like hard ice, which is cooled without supercooling and frozen on the cooling surface, Since the plate-like and needle-like fine crystals themselves grow by the cool heat from the supercooled water, the adhesion to the tube wall is weak. When the pipe wall surface to which ice adheres is made of a material having a small heat capacity and heat conduction such as resin, the ice has a weaker adhesive force and is more likely to be blown off by a water flow.

When the inner surface of the downstream end of the small-diameter pipe 4 is cut in a tapered shape as in the present invention, propagation from the periphery of the small-diameter pipe 4 to the inside is such that a phase change propagates along the tapered surface. Instead, the ice grows in the crystal direction of the ice, so that the ice grows with the ice floating from the tapered surface as shown in FIG. 2C. Therefore, as shown in FIG. 2D, the ice 13 grown by the jet flow speed of the supercooled water 10 is blown off, and the phase change does not propagate to the inner surface of the small-diameter tube 4.

FIG. 2E shows an example in which the end portion and the tapered surface of the small diameter pipe 4 are covered with a resin lining material 20 to reduce heat conduction. As described above, by making the surface of the tube wall to which ice adheres smooth without irregularities, the adhesion of ice is weakened and the ice is easily peeled off, and the effect of preventing phase change propagation becomes remarkable. When a resin pipe such as a commercially available PVC pipe is used as the small-diameter pipe 4, since the pipe surface and the cut surface of the pipe have numerous irregularities such as scratches, the ice generated from the supercooled water has a needle-like or plate-like shape. Ice easily adheres to the irregularities and does not easily peel off due to water flow. By applying a resin-based lining material there, fine scratches on the surface are covered and ice is less likely to adhere, and the resin itself is less likely to be cooled by the resin-based lining material with low thermal conductivity and heat capacity. In addition, the adhesion of ice will be weakened. Thereby, it is possible to eliminate the variation in the operation effect due to the difference in the processing accuracy and the surface of the small-diameter tube, the difference in the heat conductivity and the heat capacity, and to stably prevent the propagation of the phase change.

FIG. 3 shows an example in which a bypass circuit 11 is provided between the water circulation pump 9 and the cooler 1 and near the upstream end of the large-diameter pipe 5 of the supercooled water release device. Ice that accumulates in the vicinity can be positively removed by the bypass flow. The purpose of the bypass flow is to prevent the phase change propagation inside the small diameter pipe due to ice blockage and ice accumulation. If there is no bypass pipe, a vortex is formed near the outlet of the small-diameter pipe 4 as shown in FIG. 4A, and the generated ice gradually accumulates and is easily blocked. In addition, since ice gradually accumulates around the small-diameter tube 4, a phase change easily propagates inside the small-diameter tube 4. When the bypass pipe 11 is installed, the ice deposited by the bypass flow is taken away and removed as shown in FIG. 4B.

As shown in FIGS. 5A and 5B, the bypass pipe 11 is connected to the large-diameter pipe 5 at one or more locations in the tangential direction of the large-diameter pipe 5 so that the supercooled water from the small-diameter pipe 4 can be connected. Is connected in such a manner that a bypass flow is formed in a large-diameter pipe in a helical shape with respect to the water flow. This spiral water flow prevents the supercooled water from directly contacting the wall surface of the large-diameter pipe 5, so that the accumulation of ice on the inner surface of the large-diameter pipe 5 can be prevented.
Further, since the specific gravity of the ice is lighter than that of water, the ice is carried to the center of the spiral water flow by the spiral water flow, and is discharged downstream by the water flow of the supercooled water 10 ejected from the small-diameter pipe 4. By the above operation, the phase change propagation from the large-diameter pipe to the small-diameter pipe is prevented without using a heating means such as a heater, and ice can be stably generated.

FIG. 6 shows a further preferred embodiment of the present invention in which the small-diameter pipe 4 is protruded into the large-diameter pipe 5 in a nozzle shape to regulate the flow of the water flow around the nozzle 4a, thereby preventing the propagation of the phase change. Represents an example that can be increased. As shown in FIG. 4A, the small-diameter pipe 4
When the flow path is rapidly expanded, a vortex is formed in the large diameter pipe 5. On the other hand, by protruding the small-diameter pipe 4 in a nozzle shape as shown in FIG. 7, the flow around the tip of the nozzle 4a is adjusted in the jetting direction of the supercooled water 10, and the turbulence of the fluid at the outlet of the nozzle 4a is disturbed. Pressure fluctuations (flow rate fluctuations) due to pressure are prevented, and the supercooled water stabilizes and the phase change inducing device 7
Sent to. In addition, the flow of the fluid around the nozzle 4a is adjusted in the direction in which the supercooled water 10 is ejected, so that the ice returning from the downstream of the large-diameter pipe 5 due to the vortex flows through the nozzle 4a
This has the effect of smoothly discharging downstream without adhering to the tip. According to the present invention, by cutting the inside of the downstream end of the nozzle 4a in a tapered shape, the same effect as in the above-described example can be obtained.

FIGS. 8A to 8E are the same as those described above with reference to FIGS. 2A to 2E. When the inside of the downstream end of the small-diameter pipe 4 projecting in a nozzle shape is not cut in a tapered shape (FIGS. 8A and 8B), the phase change is easily propagated to the upstream side, but is cut in a tapered shape. In the case (FIGS. 8C and 8D), the phase change becomes difficult to propagate to the upstream side. FIG. 8E shows an example in which the inside and outside and the tapered surface of the nozzle-shaped portion 4a are covered with resin lining materials 20 and 21 to reduce heat conduction. The resin lining material may be only one of the inside and the outside.

FIGS. 9A and 9B show the effect when a bypass pipe is added to the ice making apparatus shown in FIG. Ice easily accumulates on the large-diameter pipe 5 side at the base of the nozzle 4a as shown in FIG. 9A. However, if the bypass pipe P is installed and water is introduced, the accumulated ice can be easily discharged to cause blockage. There is no. As shown in FIG. 10A, the bypass pipe P uses the pressure difference around the tip of the nozzle 4 a and the pressure difference downstream of the large-diameter pipe 5, from near the downstream end of the large-diameter pipe 5 to the tip of the nozzle 4 a of the small-diameter pipe 4. The bypass pipe 11 can be connected to the periphery, or the bypass pipe 6 can be connected between the water circulation pump 9 and the cooler 1 and around the tip of the nozzle 4a of the small diameter pipe 4 as shown in FIG. 10B. These bypass pipes are desirably connected in a tangential direction of the large diameter pipe 5 as shown in FIG.

As shown in FIG. 8E, the nozzle 4a
Is covered with a resin-based lining material 21,
It is possible to prevent ice from adhering to the outer surface of the nozzle and enhance the effect of smoothly discharging ice around the nozzle.
Further, the inner surface of the nozzle tip 4a is made of a resin lining material 20.
To reduce heat conduction and make the surface of the tube wall to which ice adheres smooth without irregularities, thereby weakening the adhesion of ice, making it easier to peel off ice and ensuring the effect of preventing phase change propagation. In addition, it is possible to eliminate the variation in the operation effect due to the difference in the processing accuracy and the surface of the nozzle, the difference in the thermal conductivity and the heat capacity, and to stably prevent the propagation of the phase change. Further, as a modification, the entire small-diameter tube 4 can be formed of a resin having a small heat capacity.

[0029]

As described above in detail, according to the present invention, it is possible to prevent a phase change from supercooled water to ice from propagating upstream without using a heating means such as a heater. An ice making device is provided. If a resin-based lining material with small thermal conductivity and heat capacity is used for the small-diameter pipe, the pipe itself is difficult to cool, which further weakens the adhesion of ice, thereby reducing the processing accuracy and surface quality of the small-diameter pipe. Scattering, variation in the operation effect due to differences in heat conductivity and heat capacity can be eliminated, and the propagation of a phase change can be stably prevented. The technical effect is extremely remarkable.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a preferred example of an ice producing apparatus according to the present invention.

FIG. 2 is a cross-sectional view illustrating a state in which a phase change from supercooled water to ice propagates upstream.

FIG. 3 is a schematic diagram illustrating an example in which a bypass pipe is provided.

FIG. 4 is a cross-sectional view for explaining an effect of the bypass pipe.

FIG. 5 is a cross-sectional view illustrating an example in which a bypass pipe flows in from a tangential direction.

FIG. 6 is a schematic diagram illustrating an example in which a small-diameter pipe projects into a large-diameter pipe.

FIG. 7 is a cross-sectional view illustrating an operation of a small-diameter tube protruding in a nozzle shape.

FIG. 8 is a cross-sectional view showing a state of progress of a phase change around a nozzle portion.

FIG. 9 is a sectional view showing the operation of the bypass pipe on the nozzle-shaped portion.

FIG. 10 is a schematic diagram illustrating an arrangement of a bypass pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooler 2 Refrigerator 3, 9 Pump 4 Small diameter pipe 4a Nozzle part 5 Large diameter pipe 6, 11 Bypass pipe 7 Phase change inducing device 8 Ice storage tank 10 Supercooled water 13 Ice 14 Tapered surface 15 Vertical disk 20, 21 Resin lining 23 Subcooling release device

Claims (7)

[Claims] A cooler for cooling water to produce supercooled water;
A supercooling release device that eliminates the supercooled state of the generated supercooled water and continuously converts the supercooled water into a mixture of water and ice, and is connected so that the water and ice flowing inside them do not come into contact with the atmosphere. The supercooling release device includes a small-diameter pipe and a large-diameter pipe, and the flow rate in the pipe at the inlet side of the supercooled water is 2.7 m /
The large-diameter pipe is fixed to the downstream end of the small-diameter pipe via a vertical disk, and the phase from the supercooled water to ice is formed on the outer periphery of the large-diameter pipe. In the ice making device provided with a phase change inducing device for inducing a change, the inside of the downstream end of the small diameter pipe is cut into a tapered shape, and the phase change from the inside of the large diameter pipe to the inside of the small diameter pipe is performed. An ice manufacturing apparatus characterized in that propagation is prevented. 2. The ice producing apparatus according to claim 1, wherein the small diameter pipe has an inner surface covered with a resin-based lining material having a small heat capacity. 3. A cooler for cooling water to produce supercooled water,
A supercooling release device that eliminates the supercooled state of the generated supercooled water and continuously converts the supercooled water into a mixture of water and ice, and is connected so that the water and ice flowing inside them do not come into contact with the atmosphere. The supercooling release device includes a small-diameter pipe and a large-diameter pipe, and the flow rate in the pipe at the inlet side of the supercooled water is 2.7 m /
s or more, the small-diameter pipe is disposed in the large-diameter pipe so as to protrude in a nozzle shape, and the large-diameter pipe on the downstream side from the nozzle-shaped portion is supplied with supercooled water. In an ice manufacturing apparatus provided with a phase change inducing device for inducing a phase change to ice, the inside of the tip of the nozzle-shaped portion is cut in a tapered shape, and the phase from the inside of the large diameter pipe to the inside of the nozzle-shaped portion is reduced. An ice manufacturing apparatus characterized by preventing change propagation. 4. The small-diameter pipe projecting in a nozzle shape,
The ice manufacturing device according to claim 3, wherein the inner surface and / or the outer surface is covered with a resin-based lining material having a small heat capacity. 5. The ice manufacturing apparatus according to claim 3, wherein the small diameter pipe is entirely made of a resin having a small heat capacity. 6. A bypass pipe for circulating and flowing water and ice from near the downstream end of the large-diameter pipe to a portion of the small-diameter pipe that protrudes in a nozzle shape. 6. The ice manufacturing device according to any one of 3 to 5. 7. The ice production according to claim 1, wherein a bypass pipe branched from an upstream pipe of the cooler for generating supercooled water is connected near an upstream end of the large-diameter pipe. apparatus.