JPH11325678A - Harvest type ice maker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a harvest type ice maker for growing ice on the surface of an ice making plate by cooling it through refrigeration cycle of refrigerant and separating the ice by warming the ice making plate in which ice making capacity is increased while reducing the quantity of refrigerant to be used and simplifying the assembling work of the ice maker. SOLUTION: First and second heat exchangers 9, 10 are provided in a refrigeration cycle and cold brine cooled indirectly at the first heat exchanger 9 by evaporating refrigerant is fed through circulation pipings 19, 21 to an ice making plate 2 or 3 in order to cool the ice making plate thus making an ice. On the other hand, hot brine warmed indirectly by the refrigerant prior to expansion at the second heat exchanger 10 is fed through circulation pipings 22, 24 to the ice making plate 2 or 3 in order to warm the ice making plate thus stripping and dropping the ice.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ice making plate which has been cooled to a temperature below the freezing point. The present invention relates to a harvesting-type ice making device that repeats repeating the process of heating the ice making plate to separate and drop ice on the surface of the ice making plate and storing the ice in a heat storage tank below the ice making plate.

[0002]

2. Description of the Related Art Conventionally, as one example of this type of harvest type ice making apparatus, there is an apparatus described in, for example, Japanese Patent Application Laid-Open No. Hei 8-261614 and configured as shown in FIG. That is, one or a plurality of first ice making plates B having a cooling passage B1 extending in the vertical direction above the heat storage tank A,
Similarly, one or a plurality of second ice making plates C each having a cooling passage C1 extending in the vertical direction are provided, and water in the heat storage tank A is pumped out by a pump D, and the ice making plates B, C So that it is sprayed on the surface at the upper end of.

On the other hand, a refrigerant such as ammonia which repeatedly evaporates and condenses is compressed by a compressor E, condensed in a condenser F, and then sent to a flash tank H while being adiabatically expanded by an expansion valve G. The refrigerant in the flash tank H is supplied to the lower end of the cooling passage B1 in the first ice making plate B via the refrigerant inlet valve J by the refrigerant pump I, and then from the upper end of the cooling passage B1 in the first ice making plate B. By returning the refrigerant from the refrigerant outlet valve K to the compressor E via the flash tank H and cooling the first ice making plate B, ice adheres to and grows on the surface of the first ice making plate B while the compressor E A part of the hot refrigerant immediately after being compressed in the second ice making plate C is supplied to the upper end of the cooling passage C1 in the second ice making plate C from the hot refrigerant inlet valve L, and then is supplied to the lower end of the cooling passage C1 in the second ice making plate C. That hot refrigerant outlet valve expansion valve than M N
After returning to the compressor E through the flash tank H through the flash tank H and warming the second ice making plate C, the ice adhering to the surface of the second ice making plate C is partially melted, and the lower heat storage is performed. Peel and fall into tank A.

When the ice adheres and grows on the surface of the first ice making plate B to a predetermined thickness, and when the ice on the surface of the second ice making plate C peels off and falls, the first ice making plate B At the same time as closing the refrigerant inlet valve J at the lower end and opening the hot refrigerant outlet valve O, the cooling passage B1 in the first ice making plate B
By closing the refrigerant outlet valve K at the upper end of the cooling passage B1 and opening the hot refrigerant inlet valve P, the hot refrigerant flows through the cooling passage B1 in the first ice making plate B. While the ice adhering to the surface is separated and dropped so as to enter the heat storage tank A, the hot refrigerant inlet valve L at the upper end of the cooling passage C1 in the second ice making plate C is closed and the refrigerant outlet valve Q is opened. By closing the hot refrigerant outlet valve M and opening the refrigerant inlet valve R at the lower end of the cooling passage C1 in the second ice making plate C,
The refrigerant is made to flow in the cooling passage C1 of the ice making plate C so that ice adheres to and grows on the surface of the second ice making plate C.

In another conventional harvesting type ice making device, as shown in FIG. 2, the flash tank H and the refrigerant pump I in FIG. 1 are eliminated, and an expansion valve I downstream of the compressor E and the condenser F is used. From the first
Cooling passages B1, C1 in ice making plate B or second ice making plate C
The refrigerant from the upper ends of the cooling passages B1, C1 in the first ice making plate B or the second ice making plate C is supplied to the compressor E from the refrigerant outlet valves K, Q. On the other hand, a part of the hot refrigerant immediately after the compressor E is supplied to the upper ends of the cooling passages B1 and C1 in the first ice making plate B or the second ice making plate C from the hot refrigerant inlet valves L and P, A configuration in which hot refrigerant from the lower ends of the cooling passages B1 and C1 in the first ice making plate B or the second ice making plate C is returned between the compressor E and the expansion valve I through hot refrigerant outlet valves M and O. I have to.

In this conventional example, the switching operation of the refrigerant inlet valves J and R, the refrigerant outlet valves K and Q, the hot refrigerant inlet valves L and P, and the hot refrigerant outlet valves M and O is the same as described above.

[0007]

However, each of these conventional harvest type ice making apparatuses directs the refrigerant, which repeatedly evaporates and condenses, directly into each of the cooling passages B1, C1 in the ice making plates B, C. In other words, each of the ice making plates B and C has a cooling refrigeration cycle in which a refrigerant that repeats evaporation and condensation flows through the cooling passages B1 and C1 in the respective ice making plates B and C. By configuring a part,. Since an expensive refrigerant that repeats evaporation and condensation must be filled in the cooling passages of each ice making plate and also in various pipes for the cooling passages, the amount of the refrigerant used is extremely large. . The cooling passages in each of the ice making plates B and C, various pipes for each of the ice making plates, and various valves are set to a high pressure legally designed pressure in preparation for the supply of hot refrigerant immediately after being compressed by the compressor. The structure must be designed to withstand high pressure, such as making it thick to withstand. . The interior of each of the ice making plates B and C and various refrigerant pipes for the same, and various valves for the refrigerant pipes are strictly designed so that foreign matter and moisture are not mixed into the refrigerant flowing therein as much as possible. This requires a lot of trouble and time, since it must be cleaned and assembled while drying sufficiently. There was a problem to say.

It is a technical object of the present invention to solve these problems and to provide an apparatus capable of further improving the refrigerating capacity.

[0009]

In order to achieve this technical object, the present invention provides a plurality of ice making plates provided with cooling passages, and means for spraying water on the surface of the upper end of each of the ice making plates. In a harvesting type ice making device having a refrigerant compressor, a condenser and a refrigeration cycle line of a refrigerant having an expansion valve, a portion of the refrigeration cycle line between the expansion valve and the compressor, An indirect first heat exchanger is provided between the condenser and the expansion valve, and an indirect second heat exchanger is provided at each of the ice making plates. A valve and an outlet valve, a hot brine inlet valve and an outlet valve are provided respectively, and the first heat exchanger is provided in a cold brine circulation line connecting between the cold brine inlet valve and the outlet valve. Inlet valve and outlet of the hot brine Hot brine circulation path which connects between, and each provided. "Say constituting the second heat exchanger.

[0010]

[Operation] In this configuration, each ice making plate is divided into one or more first ice making plates and the remaining one or more second ice making plates. On the other hand, when performing the peeling and falling of the ice on the second ice making plate, the inlet and outlet valves of the hot brine on the first ice making plate are closed and the inlet and outlet valves of the cold brine are opened, By closing the inlet and outlet valves of the cold brine in the second ice making plate and opening the inlet and outlet valves of the hot brine and operating in this state, the cold brine in the cold brine circulating line becomes the first ice making. Circulating between the cooling passage in the plate and the first heat exchanger in the refrigeration cycle line, indirectly cooled by evaporation of the refrigerant circulating in the refrigeration cycle line in the first heat exchanger, Then, since the first ice making plate is cooled by the cold brine, ice can be made on the surface of the first ice making plate.
The second in the cooling passage and the refrigeration cycle line in the ice making plate
Circulating with the heat exchanger, indirectly warmed in the second heat exchanger with the hot refrigerant before expansion in the refrigeration cycle line, and
Since the ice making plate is warmed, ice on the surface of the second ice making plate can be peeled and dropped.

In this way, while ice adheres and grows on a part of the first ice making plates among the ice making plates, the remaining second ice making plates become the second.
When the ice is peeled and dropped on the ice making plate, the cold brine inlet and outlet valves of the first ice making plate are closed and the hot brine inlet and outlet valves are opened, while the hot brine inlet valve of the second ice making plate is opened. By opening the inlet and outlet valves of the cold brine by closing the outlet valve and the outlet valve, the cold brine in the cold brine circulation line becomes the first heat exchange in the cooling passage and the refrigeration cycle line in the second ice making plate. Circulating in the first heat exchanger, the refrigerant is indirectly cooled by the evaporation of the refrigerant in the refrigeration cycle line, and the cold ice cools the second ice making plate. While ice can be made on the surface of the second ice making plate, the hot brine in the hot brine circulation line is Circulating between the second heat exchanger in the refrigerating cycle line and the second heat exchanger in the refrigeration cycle line, and indirectly heated by the hot refrigerant before expansion in the refrigeration cycle line in the second heat exchanger, and Since the first ice making plate is warmed by this hot brine, the ice that has previously adhered to and grown on the surface of the first ice making plate can be peeled off and dropped. Hereinafter, the above operations are alternately repeated. It is.

Further, each of the ice making plates is divided into a plurality of groups of three or more ice making plates, and ice is made on one or more of the plurality of groups of ice making plates. Needless to say, the ice can be separated and dropped on the ice making plates of the remaining one or more groups.

[0013]

As described above, according to the present invention, the adhesion and growth of ice on the surface of an ice making plate are indirectly controlled by the first heat exchanger provided in the refrigeration cycle line of the refrigerant which repeats evaporation and condensation. A method in which a cold cold brine is used, while the ice adhered and grown on the surface of the ice making plate is separated and dropped by a hot brine indirectly heated in a second heat exchanger in the refrigeration cycle line. And, in other words,
Cold brine and hot brine are allowed to flow at a low pressure in the cooling passage in each of the ice making plates. Since it is not necessary to charge an expensive refrigerant that repeats evaporation and condensation into the cooling passages of each ice making plate and the various conduits corresponding thereto, the amount of the refrigerant used is significantly greater than in the conventional case described above. Can be reduced. . It is not necessary to configure the cooling passages in each of the ice making plates, various conduits for each of the ice making plates, and various valves in a structure that can withstand high refrigerant pressure, and circulate brine as a secondary refrigerant. It can be configured for low pressure specifications so as to withstand only low pressure. . Since the cooling passages in each of the ice making plates, the various pipelines for each of the ice making plates, and the various valves do not flow refrigerant that must be extremely prevented from being contaminated with foreign matter and moisture. The assembly can be made extremely simple, and the number of steps and time required for the assembly can be greatly reduced as compared with the conventional case described above. It has the effect of saying.

Further, according to the present invention, the hot brine for each of the ice making plates is indirectly warmed by the second heat exchanger provided at a portion between the condenser and the expansion valve in the refrigerant refrigeration cycle line. This makes it possible to lower the temperature of the refrigerant in the refrigeration cycle line before the expansion valve by an amount that indirectly heats the hot brine with the refrigerant, thereby increasing the thermal efficiency. It also has the effect of improving

By the way, if the direction of the flow of the cold brine with respect to each ice making plate is always in one direction,
The ice on the surface of each ice making plate adheres and grows unevenly in the longitudinal direction of each ice making plate, such that the ice on the surface of each ice making plate is thicker on the inlet side of the cold brine and thinner on the outlet side of the cold brine. Also, if the direction of the flow of hot brine with respect to each ice making plate is always set to one direction, the ice adhering to the surface of each ice making plate becomes the inlet of the hot brine of each ice making plate. Despite the fact that the peeling / falling at the outlet side of the hot brine is delayed, the slower time is required as the deicing time in spite of trying to peel / fall earlier on the side, Introduces reduced ability.

On the other hand, according to the present invention, as described in claim 2, the flow of the cold brine inside the cold brine circulating pipe enters through the inlet valve for the cooling passage in each ice making plate, and the outlet. 4. A cold brine flow direction switching means for switching between a forward direction flowing out of the valve and a reverse direction flowing in from the outlet valve and flowing out of the inlet valve, and circulating hot brine as described in claim 3. In the pipeline, the flow of the hot brine therein is switched between a forward direction which enters from the inlet valve to the cooling passage in each ice making plate and flows out from the outlet valve, and a reverse direction which enters from the outlet valve and flows out from the inlet valve. It is proposed to provide a hot brine flow direction switching means.

As described above, in the cold brine circulation line, the flow direction of the cold brine is switched between the forward direction and the reverse direction by the flow direction switching means at appropriate time intervals, so that each ice making is performed. Since the thickness of ice that adheres to and grows on the surface of the plate can be made substantially uniform over the entire length of each ice making plate, the ice making capacity can be increased.

Further, as described above, in the hot brine circulation pipeline, the flow direction of the hot brine is switched between the forward direction and the reverse direction by the flow direction switching means at appropriate time intervals. Since ice can be separated and dropped on the surface of each ice making plate uniformly and quickly over the entire length of each ice making plate, the ice making capacity can be increased as described above.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. 3 to 5 show a first embodiment. In this figure, reference numeral 1 denotes a heat storage tank having an open upper surface, and FIG.
, A plurality of cooling passages 2a extending in the vertical direction
One or more first ice making plates 2 provided with
Alternatively, as shown in FIG. 5, a cooling passage 3a extending in the vertical direction
And one or a plurality of second ice making plates 3 provided with a pump, and the water in the receiving tank 1 is pumped out by the pump 4 so as to be sprayed on the surface at the upper end of each of the ice making plates 2 and 3. To be configured.

The ice making plate according to the present invention is the same as that shown in FIG.
Alternatively, the present invention is not limited to the configuration shown in FIG. 5, but as shown in FIG. 6, a cooling passage is provided in short, such as a type in which a plurality of cooling passages 2a and 3a are provided so as to extend in the lateral direction. The cooling passage in the ice making plate is not limited to a one-pass type in which the cooling fluid flows from one end to the other end, as shown in FIGS. Needless to say, it may be a two-pass type that flows in one cooling passage from one end to the other end and then flows in the other cooling passage in a folded manner from the other end to the one end.
The cross-sectional shape of the cooling passage may be an arbitrary shape such as a circular shape and a square shape.

Reference numeral 5 denotes a refrigeration cycle line that forms a refrigeration cycle of a primary refrigerant such as ammonia. In the refrigeration cycle line 5, a compressor 6 and a refrigerant compressed by the compressor 6 are provided. A condenser 7 for condensing the refrigerant and an expansion valve 8 for expanding the condensed refrigerant are provided, and a portion of the refrigeration cycle line 5 between the expansion valve 8 and the compressor 6 is provided with an indirect type. The first heat exchanger 9 is provided between the condenser 7 and the expansion valve 8 with an indirect second heat exchanger 10.

At one end of each of the ice making plates 2 and 3, there are provided inlet valves 11, 12, 13 and 14, respectively, into the cooling passages 2a and 3a. At the end, outlet valves 15, 16, from inside each cooling passage 2a, 3a,
17 and 18 are provided respectively. One of the inlet valves 11 and 12 in each of the ice making plates 2 and 3 and the first
A circulation line 19 and a circulation line 21 with a circulation pump 20 are provided between the heat exchanger 9 and between the first heat exchanger 9 and one of the outlet valves 15 and 16 of the ice making plates 2 and 3. By connecting them, cold brine such as ethylene glycol as a secondary refrigerant circulates between them.

On the other hand, between the other inlet valves 13 and 14 of the ice making plates 2 and 3 and the second heat exchanger 10, and between the other heat exchanger 10 and the other of the ice making plates 2 and 3 respectively. By connecting the outlet valves 17 and 18 with the circulation line 22 and the circulation line 24 with the circulation pump 23, respectively,
It is configured such that hot brine such as ethylene glycol as a secondary refrigerant circulates between them.

In this configuration, while ice is made on the first ice making plate 2 and the ice is separated and dropped on the second ice making plate 3, the hot brine inlet valve 13 and the outlet valve of the first ice making plate 2 are made. 17, the cold brine inlet valve 11 and the outlet valve 15 are opened, while the second ice making plate 3 is closed.
Cold brine inlet valve 12 and outlet valve 16 at
By closing the inlet and outlet valves 14 and 18 of the hot brine and operating in this state, the cold brine in the cold brine circulation lines 19 and 21 is set in each cooling passage 2 a in the first ice making plate 2. And circulating between the first heat exchanger 9 in the refrigeration cycle line 5,
In the first heat exchanger 9, the refrigerant circulating through the refrigeration cycle line 5 is indirectly cooled by evaporation of the refrigerant, and the cold ice cools the first ice making plate 2, so that the first ice making plate 2 is cooled. 2, while the hot brine in the hot brine circulation pipes 22 and 24 is connected to the second heat exchanger in each cooling passage 3a of the second ice making plate 3 and the refrigeration cycle pipe 5. 10 and is indirectly heated in the second heat exchanger 10 by the hot refrigerant before expansion in the refrigeration cycle line 5, and the second ice making plate 3 is heated by the hot brine. Since the ice is heated, the ice on the surface of the second ice making plate 3 can be separated and dropped so as to enter the lower heat storage tank 1.

As described above, while the ice adheres and grows on the first ice making plate 2 and peels off and falls on the second ice making plate 3, the cold brine inlet valve 11 and the outlet valve of the first ice making plate 2 become cold. 15 and closing the hot brine inlet valve 13 and outlet valve 17 while opening the hot brine inlet valve 14 and outlet valve 18 in the second ice making plate 3 and opening the cold brine inlet valve 12 and outlet valve 16. As a result, the cold brine circulation lines 19, 2
1 circulates between each cooling passage 3 a in the second ice making plate 3 and the first heat exchanger 9 in the refrigeration cycle line 5, and the cold brine in the first heat exchanger 9 Since the second ice making plate 3 is cooled indirectly by the evaporation of the refrigerant in the passage 5 and the cold brine cools the second ice making plate 3, ice can be made on the surface of the second ice making plate 3. The hot brine in the hot brine circulation pipes 22 and 24 is connected to the inside of each cooling passage 2 a in the first ice making plate 2 and the refrigeration cycle pipe 5.
Circulating between the second heat exchanger 10 and the second heat exchanger 10 and indirectly heated by the hot refrigerant before expansion in the refrigeration cycle 5 in the second heat exchanger 10, and the hot brine Since the first ice making plate 2 is warmed, the ice that has previously adhered and grown on the surface of the first ice making plate 2 can be separated and dropped so as to enter the lower heat storage tank 1.
Hereinafter, the above operations are alternately repeated.

That is, in the present invention, each ice making plate 2,
The cold brine cooled indirectly by the first heat exchanger 5 in the refrigeration cycle line 5 through which the primary refrigerant circulates, is attached to the ice making and the ice making by the circulation lines 19 and 21. While the cooling is performed by flowing the cooling water through the cooling passages 2a and 3a in the plates 2 and 3, the peeling and falling off of the ice adhered and grown on the surfaces of the ice making plates 2 and 3 is performed by the refrigeration cycle line 5.
This is performed by flowing hot brine indirectly heated by the second heat exchanger 10 through the cooling passages 2a and 3a in the ice making plates 2 and 3 through the circulation pipelines 22 and 24, respectively.

The above-described embodiment is directed to a case where a plurality of ice making plates are divided into one or more first ice making plates 2 and one or more second ice making plates 3. As shown,
The present invention is not limited to this, and by dividing into three or more groups of ice making plates, ice is made on an ice making plate in one or more of a part of the plurality of ice making plates, One or a plurality of the groups may be configured to peel and drop ice on the ice making plates.

By the way, in the refrigeration cycle line 5,
When the second heat exchanger 10 is not provided, the refrigerant evaporates from the state in which the refrigerant is adiabatically expanded by the expansion valve 8 to the state in the first heat exchanger 9 as shown in the Mollier diagram shown in FIG. Then, after the compressor 6 is compressed to the state thereof, the refrigerant is cooled to the state of the condenser 7.

On the other hand, as described above, the second heat exchanger 10 is provided in a portion of the refrigeration cycle line 5 between the condenser 7 and the expansion valve 8, and the second heat exchanger 10 is provided. Vessel 1
0, the hot brine is indirectly warmed, and further, each of the ice making plates 2 and 3 is warmed by the hot brine to separate and drop ice on the surface. In the path 5, the refrigerant cooled to the state in the condenser 7 is further cooled in the second heat exchanger 10 to the state of 'as shown in the Mollier diagram shown in FIG. The valve 8 adiabatically expands to the state of '. In other words, by providing the second heat exchanger 10, a refrigeration cycle of '----' is drawn, which is compared with a refrigeration cycle of---when the second heat exchanger 10 is not provided. The thermal efficiency can be improved.

Further, as in the first embodiment,
Cold and hot brine are added to each ice plate 2,
When the cooling passages 2a and 3b are supplied from one end to the cooling passages 3 and flow out from the other end, the ice that adheres to and grows on the surfaces of the ice making plates 2 and 3 is removed from the ice making plates 2 and 3 respectively. Of the ice making plates, they are attached and grown unevenly in the longitudinal direction of each of the ice making plates 2 and 3 so as to be thicker at the inlet side of the cold brine and thinner at the outlet side of the cold brines. The ice that has adhered to and grown on the surfaces of the plates 2 and 3 tends to separate and drop at the hot brine entrance side of the ice making plates 2 and 3, but the separation and fall at the hot brine exit side is slow. As a result, a later time is required as the deicing time, and in any case, the ice making capacity is reduced.

On the other hand, as in the second embodiment shown in FIG. 8, both cold brine circulation lines 19, 21 for connecting between the first heat exchanger 9 and the ice making plates 2, 3 are provided. On the other hand, valves 25a and 25b provided in each of the two circulation pipelines 19 and 21 and two pipelines 25c and 25d connecting between the two circulation pipelines 19 and 21 are provided. A cold brine flow direction switching means 25 is provided which is constituted by valves 25e and 25f provided in the conduits 25c and 25d.

That is, the cold brine flow direction switching means 25 opens the two valves 25a and 25b and closes the other two valves 25e and 25f, thereby changing the cold brine to each of the ice making plates 2 and 3. Cooling passage 2
a, 3a flow in the forward direction from one end to the other end, and the two valves 25a, 25b are closed, and the other two valves 25a, 25b are closed.
By opening e and 25f, the cold brine is caused to flow through the cooling passages 2a and 3a in the ice making plates 2 and 3 in the opposite direction from the other end to the one end.

Further, as in the second embodiment shown in FIG. 8, both hot brine circulation pipelines 22, 24 connecting between the second heat exchanger 10 and the ice making plates 2, 3 are provided. A valve 26 provided in each of the two circulation lines 22 and 24
a and 26b, two pipes 26c and 26d connecting between the two circulation pipes 22 and 24, and the two pipes 26
There is provided a hot brine flow direction switching means 26 composed of valves 26e and 26f provided in c and 26d.

That is, the hot brine flow direction switching means 26 opens the two valves 26a and 26b and closes the other two valves 26e and 26f, thereby changing the hot brine to each of the ice making plates 2 and 3. Cooling passages 2a, 3
a in the forward direction from one end to the other end, the two valves 26a and 26b are closed, and the other two valves 26e and 26
f, hot brine is added to each ice plate 2,
The inside of each cooling passage 2a, 3a in 3 is made to flow in the reverse direction from the other end to one end.

As described above, the cold brine circulation direction lines 19 and 21 are provided with the cold brine flow direction switching means 25 so that the flow direction of the cold brine can be switched between the forward direction and the reverse direction for an appropriate time. By performing the process at intervals, the thickness of ice adhering to and growing on the surfaces of the ice making plates 2 and 3 can be made substantially uniform over the entire length of the ice making plates 2 and 3.

The hot brine circulation line 2
2 and 24, the hot brine flow direction switching means 2
6 is provided, and the flow direction of the hot brine is switched between the forward direction and the reverse direction at appropriate time intervals, so that the peeling of the ice on the surfaces of the ice making plates 2 and 3 is performed. 3 can be performed uniformly and quickly over the entire length.

Further, as in the third embodiment shown in FIG. 9, the circulation lines 19 and 21 of the cold brine are
A bypass pipe 28 with a flow control valve 27 communicating between them is provided, and a flow control valve 29 is provided in one of the circulation pipes 19 so that the cold brine flowing through the cooling passages 2a, 3a in the ice making plates 2, 3 is provided. By increasing the flow rate and thus increasing the flow velocity of the cold brine in the cooling passages 2a and 3a, it is possible to increase the heat transfer coefficient of the cold brine to each ice making plate.

In addition, as in the third embodiment shown in FIG. 9, a bypass line 3 with a flow control valve 30 communicating between the circulation lines 22 and 24 of the hot brine is provided.
1 and a flow control valve 32 in one of the circulation pipelines 22 to increase the flow rate of the hot brine flowing through the cooling passages 2a and 3a in each of the ice making plates 2 and 3, and thus the cooling passages 2a and 3a. By increasing the flow velocity of the hot brine, the heat transfer coefficient of the hot brine to each ice making plate can be increased.

[Brief description of the drawings]

FIG. 1 is a diagram showing a conventional harvest type ice making device.

FIG. 2 is a diagram illustrating another conventional harvest-type ice making device.

FIG. 3 is a diagram showing a first embodiment of the present invention.

FIG. 4 is a perspective view showing an example of an ice making plate.

FIG. 5 is a perspective view showing another example of the ice making plate.

FIG. 6 is a perspective view showing another example of the ice making plate.

FIG. 7 is a Mollier chart showing a refrigeration cycle of the present invention.

FIG. 8 is a diagram showing a second embodiment of the present invention.

FIG. 9 is a diagram showing a third embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 1 heat storage tank 2 first ice making plate 3 second ice making plate 2a, 3a cooling passage 5 refrigeration cycle line 6 compressor 7 condenser 8 expansion valve 9 first heat exchanger 10 second heat exchanger 11, 12 cold brine Inlet valve 15,16 Outlet valve for cold brine 13,14 Inlet valve for hot brine 17,18 Outlet valve for hot brine 19,21 Circulating pipeline for cold brine 22,24 Circulating pipeline for hot brine 25 Flow direction of cold brine Switching means 26 Hot brine flow direction switching means

Claims (3)

[Claims] 1. A plurality of ice making plates provided with cooling passages, means for spraying water on the surface of the upper end portion of each of the ice making plates, and a refrigerant refrigeration provided with a compressor, a condenser and an expansion valve for the refrigerant. In a harvest type ice making apparatus having a cycle line, a part of the refrigeration cycle line between the expansion valve and the compressor is provided with an indirect first heat exchanger, the condenser and the expansion valve. In each of the ice making plates, an inlet valve and an outlet valve of a cold brine, and an inlet valve and an outlet valve of a hot brine for the cooling passage are provided on the respective ice making plates. A hot brine for connecting the first heat exchanger between an inlet valve and an outlet valve of the hot brine in a cold brine circulation line connecting the inlet valve and the outlet valve of the cold brine; In the circulation line, the second heat A harvest-type ice making device, wherein each of the exchangers is provided. 2. The cold brine circulation line according to claim 1, wherein a flow of the cold brine inside the cold brine is supplied from an inlet valve to a cooling passage in each ice making plate, and flows out of an outlet valve. A harvest type ice maker comprising cold brine flow direction switching means adapted to switch between a reverse direction flowing in from a valve and flowing out of an inlet valve. 3. The hot brine circulation line according to claim 1, wherein a flow of the hot brine inside the circulation line enters a cooling passage in each ice making plate through an inlet valve and flows out of an outlet valve. A harvest-type ice making device comprising hot-brine flow direction switching means for switching the flow direction from the inlet to the outlet and from the inlet valve to the opposite direction.