JP2768020B2 - Ice storage device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ice heat storage device used for air-conditioning a building or the like and for producing and processing food cooled or refrigerated at an ice temperature.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing a conventional ice heat storage device described in, for example, Japanese Patent Application No. 1-229519.
In the figure, reference numeral 1 denotes a refrigerator, which includes a compressor 2, a condenser 3, a flow control valve 4, and an evaporator 5 as main constituent devices. 6
Is a heat storage tank for storing ice and water, 7 is an aqueous solution to which a supercooling can be stably obtained in a large amount, for example, a potassium salt or a sodium salt, 8 is ice suspended in the aqueous solution 7, 9 is
Is a supercooling canceling means, which is, for example, an ice block of a predetermined size and is provided near the outlet of the supercooled aqueous solution. 10 is an ice removing device which is a filter for filtering ice 8 in the aqueous solution 7;
11 is a circulation pump for circulating the aqueous solution 7, 12 is connected to one of the heat storage tanks 6, and the ice removing device 10, the circulation pump 11,
A circulation path to which the evaporators 5 are sequentially connected to guide the aqueous solution 7 cooled by the evaporators 5 to the supercooling release means 9 in the heat storage tank 6. In addition, the aqueous solution 7 may use only water without adding additives.

Next, the operation will be described. The aqueous solution 7 subcooled to a few degrees below the freezing point (approximately −2 ° C.) by the evaporator 5 of the refrigerator 1 is a subcooling release unit 9 provided above the heat storage tank 6 through the circulation path 12. The supercooled state is broken by an ice block of a predetermined size, and small pieces of ice 8 corresponding to the amount of supercooled heat are obtained. The ice 8 flows into the heat storage tank 6 together with the remaining aqueous solution 7 that has not become ice, and floats in the heat storage tank 6 above the aqueous solution 7 having a freezing point temperature (0 ° C.). The aqueous solution 7 at the lower part of the heat storage tank 6 is sent to the refrigerator 1 by the circulation pump 11 through the ice filter 10 to constitute a cycle.

On the other hand, the refrigerator 1 has a pressure took enthalpy pressure, the horizontal axis on the vertical axis in FIG. 5 - As shown in the operation explanatory diagram of the refrigerator based on the enthalpy chart, the condenser 3 the refrigerant outlet saturation The liquid and the refrigerant at the outlet of the evaporator 5 are controlled by the flow control valve 4 so as to become a saturated gas.

[0005]

As described above, in the conventional ice heat storage device, the ice in the water or the aqueous solution in the heat storage tank flows into the evaporator of the refrigerator, and this serves as a nucleus to form the ice in the evaporator. (1) The size is several tens μm to several hundred μm because an ice filter is provided in the water circulation path on the evaporator inlet side in order to prevent it from being generated inside and destroying the device. If in order to capture the small ice crystals, filtering of ice filter - must considerably finer ones, thereby the power of the large circulation pump flow resistance of the circulating water in size Kunar. (2) Clogging of the filter of the filter occurs, and maintenance for clogging of the filter is required. There were problems such as.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is intended to prevent ice in water or an aqueous solution from flowing into an evaporator of a refrigerator, thereby providing a stable and efficient operation. It is an object of the present invention to obtain an ice heat storage device capable of performing the above.

[0007]

The ice heat storage device of the present invention comprises:
Compressor, condenser, flow control valve, and evaporator are connected in sequence to form a refrigerator that supercools water or an aqueous solution obtained by adding an additive to water, and releases supercooling of supercooled water or an aqueous solution. And supercooling releasing means for generating ice, a heat storage tank for storing the generated ice and supercooled water, a circulation pump for feeding and circulating water or an aqueous solution in the heat storage tank to the evaporator, and these in order. Connected, provided with a circulation path through which the water or aqueous solution circulates, a heater is provided between the condenser and the flow control valve, and the water or aqueous solution supplied from the heat storage tank passes through the heater. The above-mentioned circulation path is formed so as to flow into the evaporator, and a heater is provided in the above-mentioned circulation path.
Bypass path, above this bypass path
Water or water placed in a stream and fed from a heat storage tank to an evaporator
Ice detecting means for detecting the presence or absence of ice in the solution;
Or the flow path of the aqueous solution is circulated through the heater or
A flow path switching means for switching to any one of the path flow paths is provided .

[0008]

[0009]

The heater in the ice heat storage device of the present invention heats and melts ice of water or an aqueous solution obtained by adding an additive to water (hereinafter simply referred to as an aqueous solution including water). It can be prevented from flowing into the evaporator, the destruction of the device can be prevented, and stable continuous operation can be performed. Further, since the aqueous solution is heated by the heat of the refrigerant of the refrigerator, the cooling capacity of the evaporator is increased, the filter is not required, the power of the circulating pump can be reduced, and the operation can be performed with high efficiency.

Further, the presence or absence of ice is detected by the ice detecting means, and when there is no ice and heating is not required, the flow path is switched to the heater by switching the flow path so that the aqueous solution flows through the bypass flow path bypassing the heater. Since the cooling can be performed without flowing the aqueous solution, the cooling rate at that time can be increased and the operation can be performed with high efficiency.

[0011]

[Embodiment 1] An embodiment of the present invention will be described below with reference to the drawings. FIG.
1 is a configuration diagram illustrating an ice heat storage device according to a first embodiment of the present invention;
In the figure, reference numeral 22 denotes a condenser 3 and a flow control valve 4 of the refrigerator 1.
The circulation path 12 is formed so that the aqueous solution circulates in the order of the heat storage tank 6, the circulation pump 11, the heater 22, and the evaporator 5. Reference numeral 24 denotes ice detecting means for detecting the presence or absence of ice in the aqueous solution.
Provided at the inlet of the heater 22, the first temperature sensor over for detecting the presence or absence of ice by detecting the temperature of the aqueous solution, 25 detects the temperature of the aqueous solution provided in the outlet of the heater 22 in the circulation path 12 a second temperature sensor over. 28 is in the circulation path 12,
One is connected between the first temperature sensor 24 and the heater 22
And the other is connected between the heater 22 and the second temperature sensor 25.
A bypass provided to bypass the heater 22
A flow path 26 is branched from a bypass flow path 28 of the circulation path 12.
Switching of flow path installed downstream and upstream of heater 22
The first on-off valves 26 and 27 that constitute the means are provided in the bypass passage 2
8, which also constitutes the flow path switching means.
An on-off valve that passes through the first on-off valve 26 from the circulation pump 11
From the circulation pump 11 to the heater 22
The evaporator passes through the second opening / closing valve 27 and bypasses the heater 22.
5 and a path through the bypass flow path 28 leading to
You. Note that the other configuration is the same as the conventional one, and the description is omitted.

Next, the operation will be described. The refrigerator 1 based on this embodiment has two operation modes. They are the first temperature sensor-2 provided at the entrance of the heater 22.
4 when the temperature of the aqueous solution 7 is equal to or higher than 0 ° C. (it is determined that ice does not exist), and when the temperature of the aqueous solution 7 reaches 0 ° C. (when ice exists). This is the second operation mode. Hereinafter, each operation mode will be described.

The first operation mode (when the temperature of the aqueous solution 7 is 0 ° C.)
In the above case, for example, when the ice heat storage device is started), the flow rate of the refrigerant is controlled such that the refrigerant at the outlet of the condenser 3 becomes a saturated liquid and the refrigerant at the outlet of the evaporator 5 becomes a saturated gas, similarly to the operation of the conventional device. Valve 4 is controlled. Also, the first on-off valve 26
Is closed, the second on-off valve 27 is opened, and the aqueous solution 7
2 to bypass the evaporator 5 while bypassing the evaporator 5
Flow 8 Thus, the aqueous solution 7 is not Rukoto heated by the heater 22 is cooled to a supercooled state in a few degrees below freezing in the evaporator 5, the supercooling is released by supercooling release means 9, subcooling equivalent ice Is generated and cooled to return to the heat storage tank 6.

The operation in the first operation mode causes the aqueous solution 7
When the temperature of the water drops and the core of the ice 8 is mixed in the aqueous solution 7 (when the temperature of the aqueous solution 7 reaches 0 ° C. ) , the second operation mode is set. When the temperature of the first temperature sensor over 24 with an aqueous solution 7 provided in the aqueous solution inlet of the heater 22 detects that a 0 ° C., the first on-off valve 26 opens, the second on-off
Close valve 27 so that aqueous solution 7 flows to heater 22
Control. And, the second provided at the outlet of the heater 22
Water temperature detected by the temperature sensor over 25 is controlled to be + 0.5 ° C. approximately. That is, as shown in an operation explanatory diagram of a refrigerator based on a pressure-enthalpy diagram with pressure on the vertical axis and enthalpy on the horizontal axis in FIG. 2, the refrigerant gas discharged from the compressor 2 The liquid is partially cooled and liquefied, flows into the heater 22 in that state, and exchanges heat with the aqueous solution 7 (the aqueous solution 7
After heating) to become a saturated liquid. The liquid refrigerant is reduced to a low pressure by the flow control valve 4 and then flows into the evaporator 5.
The heat is exchanged with the aqueous solution 7 (the aqueous solution 7 is cooled) to become a refrigerant gas, and the refrigerant at the outlet of the evaporator 5 is controlled so as to be slightly heated, and is sucked into the compressor 2. Accordingly, in this operation mode, 0 ° C. water supplied from the heat storage tank 6 by the circulation pump 11 is used.
The aqueous solution 7 is heated to about + 0.5 ° C. at which the core of the ice 8 is sufficiently melted in the heater 22, then cooled to a supercooled state by the evaporator 5 and returned to the heat storage tank 6.

Further pressure in FIG. 3 - refrigerant of the condenser 3 outlet may be controlled to be the saturated liquid as shown in diagram for describing operation of the refrigerator based on the enthalpy chart. In this case, since the refrigerant liquid is supercooled in the heater 22 after leaving the condenser 3,
The enthalpy change in the evaporator 5 is increased, and there is an effect that the efficiency of the refrigerator is improved.

As described above, in this embodiment, since the aqueous solution 7 before flowing into the evaporator 5 is heated by passing through the heater 22, ice crystal nuclei flow into the evaporator 5. Freezing can be prevented, and stable continuous operation can be performed. Further, since the aqueous solution is heated by the heat of the refrigerant of the refrigerator 1 without providing another heat source such as an electric heater, the cooling capacity of the evaporator 5 is increased, and the electric input is not increased and the efficiency is high. Can be operated. Further, a filter as in the conventional example becomes unnecessary, the power of the circulation pump 11 can be reduced, and the maintenance of the filter becomes unnecessary. Further, when the temperature of the aqueous solution 7 in which no ice
During the first operation mode at a temperature of at least
Because cooling can be done without flowing water, cooling speed can be increased
In addition, highly efficient operation is possible.

[0017]

In the above embodiment, the heater 22 is provided between the circulation pump 11 and the evaporator 5, but the same effect can be obtained by providing the heater 22 between the heat storage tank 6 and the circulation pump 11. There is.

In the above embodiment, the flow control valve 4 is controlled so that the refrigerant at the outlet of the evaporator 5 is slightly heated in the second operation mode. However, the refrigerant at the outlet of the condenser 3 is slightly overheated. It may be controlled to cool.

In the above embodiment, the first temperature sensor 24 is provided at the inlet of the heater 22 as the ice detecting means. However, instead of the temperature sensor, the amount of transmitted light or the like is detected and the ice 8 is detected. May be detected.

Further, in the above embodiment, the supercool release means 9
Has been described as an ice block of a predetermined size provided near the outlet of the supercooled aqueous solution, but may be a metal plate-like object such as stainless steel.

Furthermore, although the first and second on-off valves 26 and 27 constitute a flow path switching means, a three-way valve is provided at the branch between the circulation path 12 and the bypass flow path 28. Is also good.

[0023]

As described above, according to the present invention, a compressor, a condenser, a flow control valve, and an evaporator are sequentially connected to each other to supercool water or an aqueous solution obtained by adding an additive to water. A refrigerator, a supercooling canceling means for canceling the supercooling of the water or aqueous solution supercooled by the refrigerator and generating ice, and a heat storage for storing the ice or supercooled water generated by the supercooling canceling means. Tank, a circulating pump for supplying and circulating water or an aqueous solution in the heat storage tank to the evaporator, and an ice heat storage device having a circulation path for connecting these in order and circulating the water or the aqueous solution, wherein the condenser and A heater is provided between the flow control valves, and the circulation path is formed so that water or an aqueous solution supplied from the heat storage tank flows into the evaporator through the heater, and a heater is provided in the circulation path.
Bypass path, above this bypass path
Water or water placed in a stream and fed from a heat storage tank to an evaporator
Ice detecting means for detecting the presence or absence of ice in the solution;
Or the flow path of the aqueous solution is circulated through the heater or
Since the flow path switching means for switching to any of the pass flow paths is provided, the aqueous solution flowing into the evaporator is heated by the heat of the refrigerant of the refrigerator, and the ice crystal nuclei flow into the evaporator. Prevent,
Since the freezing can be prevented, continuous operation can be stably performed, and high-efficiency operation can be performed. In addition,
Alternatively, the aqueous solution can be supplied to the heater when no ice is present.
Cooling can be performed without flowing, so the cooling rate at that time can be increased
At the same time, highly efficient operation becomes possible.

In addition to the above, in addition to the above, a bypass passage for bypassing the heater in the circulation path of the water or the aqueous solution, ice detecting means for detecting the presence or absence of ice in the water or the aqueous solution fed from the heat storage tank to the evaporator, And a flow path switching means for switching the flow path of the water or the aqueous solution to either a circulation path or a bypass flow path passing through the heater, so that the heating can be selectively performed, and the aqueous solution is supplied to the heater when ice is not present. Cooling can be performed without flowing water, so the cooling rate can be increased at that time,
Highly efficient operation is possible.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an ice heat storage device according to a first embodiment of the present invention.

FIG. 2 is an operation explanatory diagram of the refrigerator based on a pressure-enthalpy diagram showing an operation example by the refrigerator of Embodiment 1 of the present invention.

FIG. 3 is an operation explanatory diagram of the refrigerator based on a pressure-enthalpy diagram showing another operation example of the refrigerator of Embodiment 1 of the present invention.

FIG. 4 is a configuration diagram showing a conventional ice heat storage device.

FIG. 5 shows the operation of a conventional ice heat storage device by a refrigerator.
FIG. 8 is an explanatory diagram of the operation of the refrigerator based on the pressure-enthalpy diagram.
You.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Refrigerator 2 Compressor 3 Condenser 4 Flow control valve 5 Evaporator 6 Heat storage tank 7 Water or aqueous solution which added the additive to water 8 Ice 9 Subcooling release means 11 Circulation pump 12 Circulation path 22 Heater 24 Ice detection means second on-off valve 28 the bypass flow passage is a first on-off valve 27 the flow path switching means is a first temperature sensor over 26 flow path switching means is

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazunari Nakao 8-1-1 Tsukaguchi Honcho, Amagasaki City Mitsubishi Electric Corporation Central Research Laboratory (72) Inventor Shinichi Wakamoto 8-1-1 Tsukaguchi Honcho Amagasaki City No. Mitsubishi Electric Corporation Central Research Laboratory (56) References JP-A-4-222372 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F24F 5/00

Claims (1)

(57) [Claims] 1. A refrigerator configured to sequentially connect a compressor, a condenser, a flow control valve, and an evaporator, and supercools water or an aqueous solution obtained by adding an additive to water. The supercooling release means for releasing the supercooling of the water or the aqueous solution and generating ice, the heat storage tank for storing the ice or the supercooled water generated by the supercooling release means, the water or the aqueous solution in the heat storage tank. A circulation pump that feeds and circulates to the evaporator, and these are connected in order, in an ice heat storage device including a circulation path through which the water or the aqueous solution circulates, a heater is provided between the condenser and the flow control valve, While forming the circulation path so that water or aqueous solution sent from the heat storage tank flows into the evaporator via the heater ,
A bypass passage for bypassing the heater to the circulation path,
Installed upstream of the bypass flow path and sent from the heat storage tank to the evaporator
Ice detection to detect the presence of ice in the supplied water or aqueous solution
Means, and the flow path of the water or the aqueous solution passes through the heater.
A flow path that switches between a circulation path and a bypass flow path
An ice heat storage device comprising switching means .