JPH11141928A - Ice heat storage apparatus and air conditioning system therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a cooling fluid in a cooler from being frozen. SOLUTION: Control means C controls operation such that based upon the degree of supercooling ΔT1 of a cooling fluid L' detected by a cooling fluid temperature detector 22 and saturation temperature Ts of a refrigerant corresponding to evaporation pressure detected by a pressure detector 6p, revolutions of a compressor 1 are temporarily lowered when the saturation temperature Ts reaches a preset lower limit in response to the degree of supercooling of the cooling fluid L'. As a result, the saturation temperature Ts(evaporation pressure) of the refrigerant is prevented from being further lowered than necessary in response to the degree of the supercooling ΔT1 of the cooling fluid L', and hence the cooling fluid L' in the supercooler 4 is prevented from being frozen.

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 utilizing ice generated from a supercooled cooling liquid.

[0002]

2. Description of the Related Art Generally, an ice heat storage device is a device for generating ice using inexpensive nighttime electric power and using the ice as a heat source in the daytime, and is mainly used for an air conditioning system. Such ice heat storage devices are roughly classified into a static type that generates hard ice around a heat transfer tube and a dynamic type that generates slurry-like (sorbet-like) ice according to a method of generating ice. Among them, the latter dynamic ice heat storage device has been actively developed in recent years because it can use ice more efficiently than the static ice heat storage device in that additional ice making can be performed.

[0003] Among such dynamic type ice heat storage devices, in particular, a cooling liquid (water or aqueous solution) is cooled to a supercooled state by a supercooler (heat exchanger), and the supercooled state is stored in the ice heat storage tank. Those that generate ice by releasing have the advantage that ice in the form of slurry can be generated and accumulated at a relatively low cost.

However, in an apparatus using such a supercooled cooling liquid, the originally unstable supercooled cooling liquid is used.
It is necessary to be able to supply to the ice heat storage tank without freezing in the subcooler. For this reason, in the conventional ice heat storage device of this type, a brine method in which ice is made using brine such as ethylene glycol or propylene glycol, which is easy to control the temperature, and cool water is used with water or brine is mainly used.

FIG. 24 shows an example of such a brine type apparatus. In the ice heat storage device shown in FIG. 24, the coolant L sent out of the ice heat storage tank 50 by the coolant pump 67 is sent from the brine cooler 65 to the supercooler (heat exchanger) 54 by the brine pump 68. It is configured to exchange heat with brine and cool to a supercooled state. Note that in FIG.
2 indicates a load side where the heat storage of the ice heat storage tank 50 should be used,
Reference numeral 64 denotes a water sprinkling pipe for spraying water into the ice heat storage tank 50.

On the other hand, as shown in FIG. 25, there is also known an ice heat storage device in which a brine system is omitted, and cooling is performed by directly exchanging heat between a refrigerant and a cooling liquid by a supercooler (Japanese Patent Application Laid-Open No. HEI 9-259572). 5-296503). The ice heat storage device shown in FIG. 25 includes a refrigerator 70 having a condenser 72, an evaporator 74, and a compressor 71 connected to a cooling tower 75;
And an ice heat storage tank 50a for storing ice I.
The cooling liquid L is configured to be cooled by exchanging heat with the refrigerant of the refrigerator 70 in the evaporator (supercooler) 74.

[0007] According to such an apparatus, the evaporation temperature in the refrigerator 70 can be made higher than that of the brine type apparatus, and the efficiency of the refrigerator 70 can be improved. Further, as compared with the above-described brine type apparatus, the system configuration is simplified, and the installation space and equipment costs can be reduced.

However, in the apparatus shown in FIG. 25, the refrigerant and the coolant are directly heat-exchanged by the supercooler 74. It is difficult to stabilize. Therefore, as shown in FIG. 26, the temperature of the coolant in the subcooler 84 is detected by the temperature detectors 84t and 84t ', and the control means C' controls the compressor 81 in the refrigerator 80 according to the detected temperature. There has also been proposed a device for controlling the operation stop and the rotation speed of the pump 87 for circulating the coolant to keep the degree of supercooling constant.

In FIG. 26, reference numerals 82 and 8
Reference numeral 3 denotes a condenser and an expansion valve of the refrigerator 80, respectively, and reference numerals 50b and 82 denote an ice heat storage tank and a load side on which the heat storage is to be used, respectively.

Next, in the event that the cooling liquid is frozen in the subcooler, the compressor is usually stopped to wait for the freeze to be released, or the gas balance of the refrigerant is checked after the compressor is stopped. Therefore, it is necessary to switch the refrigeration cycle to the heating operation state and release the freezing by the hot gas. Therefore,
In order to cope with such a need for freezing, an apparatus having a plurality of supercoolers as shown in FIGS. 27 and 28 has been proposed.

First, the apparatus shown in FIG. 27 stops the supply of brine to the frozen subcooler 104 when one of the plurality (four in this case) of the subcoolers 104 freezes. It is configured to wait for the release of the freezing while making ice by the remaining subcooler 104. 27, reference numerals 100 and 114 denote a brine cooler and a brine centrifugal chiller, respectively.
Reference numerals 105 and 105 denote an ice heat storage tank and a supercooling release pipe, respectively.

The apparatus shown in FIG. 28 is a system in which a plurality of (in this case, three) subcoolers 94 are frozen.
The supply of brine to the condenser 92 is stopped (by closing the valve 98), and the hot gas from the condenser 92 is removed (by the valve 96).
Is opened) and supplied to the subcooler 94 to release the freezing. In FIG. 28, reference numeral 91 denotes a compressor of a brine cooling system.

[0013]

The above-described ice heat storage device has the following problems. That is, FIG.
In the apparatus shown in FIG. 26 and FIG. 26, it is difficult to keep the degree of supercooling constant in an actual environment, and when the temperature of the refrigerant suddenly drops due to a sudden change in the outside air temperature or the influence of wind, etc. It is difficult to prevent freezing of the cooling liquid in the coolers 74 and 84. In addition, the subcoolers 74, 84
In the case where the coolant is cooled by the refrigerant in
The stable control region in which the supercooled state of the coolant can be kept constant is extremely narrow due to the temperature state of the refrigerant inside and before and after the subcoolers 74 and 84. For this reason, the subcooler 7
4, 84, there is a problem that the possibility of freezing varies from device to device.

Further, in these apparatuses, when freezing occurs in the subcoolers 74 and 84 during the ice making operation, it is necessary to temporarily stop the ice making operation and remove or melt the ice in the subcoolers 74 and 84. Therefore, there is a problem that it takes a long time to return to the ice making operation after the occurrence of freezing.

In the apparatus shown in FIGS. 27 and 28, since a plurality of subcoolers 94 and 104 are used, the ice making operation can be continued even if freezing occurs in any of the subcoolers 94 and 104. However, there is a problem that the entire system configuration becomes complicated and the equipment cost increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and is intended to prevent the freezing of a cooling liquid in a subcooler so that the supercooling liquid can be continuously and stably generated. In addition to providing a heat storage device, the present invention also provides an ice heat storage device having a simple configuration and capable of quickly returning from freezing to ice making operation even if freezing occurs in a subcooler. Its main purpose is to:

[0017]

The first means is that a refrigeration cycle including at least a compressor, an outdoor heat exchanger, an expansion mechanism and a subcooler connected to each other, and the subcooler is set to a supercooled state. An ice heat storage tank for accumulating ice and coolant generated from the coolant, a coolant temperature detector for detecting a degree of subcooling of the coolant at an outlet side of the subcooler, and the subcooler A pressure detector for detecting the evaporation pressure of the refrigerant at the outlet side of the compressor, and control means for controlling the number of revolutions of the compressor, wherein the control means is configured to control the cooling temperature detected by the coolant temperature detector. Based on the degree of supercooling of the liquid and the saturation temperature of the refrigerant corresponding to the evaporating pressure detected by the pressure detector, the saturation temperature is reduced to a lower limit preset according to the degree of subcooling of the cooling liquid. When the rotation speed of the compressor is An ice thermal storage apparatus and decreases in a time manner.

According to the first means, the saturation temperature (evaporation pressure) of the refrigerant can be increased by temporarily lowering the rotation speed of the compressor.
By performing the control as described above, the freezing of the coolant in the subcooler is prevented by preventing the saturation temperature (evaporation pressure) of the refrigerant from being lowered more than necessary according to the degree of supercooling of the coolant. be able to.

The second means includes a refrigeration cycle which connects at least a compressor, an outdoor heat exchanger, an electric control valve as an expansion mechanism, and a subcooler, and a cooling system which is brought into a supercooled state by the subcooler. An ice heat storage tank for accumulating ice and cooling liquid generated from the liquid; a cooling liquid temperature detector for detecting a degree of subcooling of the cooling liquid at an outlet side of the subcooler; A pressure detector for detecting the evaporating pressure of the refrigerant on the outlet side, and a control unit for controlling the opening of the electric control valve, the control unit,
The degree of supercooling of the coolant detected by the coolant temperature detector,
When the saturation temperature reaches a lower limit preset according to the degree of supercooling of the coolant based on the refrigerant saturation temperature corresponding to the evaporation pressure detected by the pressure detector, the electric motor An ice heat storage device characterized by temporarily increasing the opening of a control valve.

According to this second means, the saturation temperature (evaporation pressure) of the refrigerant can be increased by temporarily increasing the opening of the electric control valve.
By performing the control as described above, the freezing of the coolant in the subcooler is prevented by preventing the saturation temperature (evaporation pressure) of the refrigerant from being lowered more than necessary according to the degree of supercooling of the coolant. be able to.

According to a third aspect, in the first or second aspect, the lower limit value of the saturation temperature of the refrigerant is set so as to increase as the degree of supercooling of the coolant decreases. .

According to the third means, in the first or second means, the lower limit value of the saturation temperature of the refrigerant used for control is set so as to increase as the degree of supercooling of the coolant decreases. Therefore, the saturation temperature (evaporation pressure) can be maintained higher than when the cooling liquid is unstable and the supercooling degree is low, and the supercooling degree itself can be controlled so as not to be reduced more than necessary.

According to a fourth aspect, in the first or second aspect, the lower limit value of the saturation temperature of the refrigerant is set so as to increase as the degree of supercooling of the coolant decreases. .

According to the fourth means, in the first or second means, the state in which the region where the coolant is placed in the supercooled state due to the increase in the degree of superheating of the refrigerant in the subcooler becomes too large. By avoiding this, it is possible to control so that the cooling of the cooling liquid is finished as much as possible near the outlet of the subcooler. For this reason, the possibility of freezing of the cooling liquid in the subcooler can be reduced.

Fifth means is the fourth means, wherein the control means temporarily reduces the rotational speed of the compressor when the time rate of change of the degree of superheat reaches a predetermined upper limit. Alternatively, the opening degree of the electric control valve is temporarily increased.

According to the fifth means, similarly to the fourth means, it is possible to avoid a state in which the region where the coolant is placed in the supercooled state due to an increase in the degree of superheat of the refrigerant in the subcooler becomes too large. Thus, the cooling of the cooling liquid can be controlled so as to end as much as possible near the outlet of the supercooler.

In a sixth aspect, in the first or second means, when the freezing frequency of the subcooler reaches a predetermined upper limit, the lower limit of the saturation temperature of the refrigerant is changed. Is what is being done.

According to the sixth means, in the first or second means, the lower limit of the saturation temperature of the refrigerant is adjusted such that the frequency of freezing of the coolant in the subcooler is equal to or lower than the predetermined upper limit. Therefore, the effect of preventing freezing by the control of the first or second means can be improved. Further, it is possible to suppress the occurrence of freezing due to the variation in the detection error of the pressure detector for each device.

A seventh means according to any one of the first to sixth means, wherein the refrigeration cycle is provided with a bypass circuit which bypasses the subcooler and has an opening / closing valve. The on-off valve of the bypass circuit is temporarily opened when the saturation temperature reaches the lower limit.

According to the seventh means, in any one of the first to sixth means, the flow rate of the refrigerant to the subcooler is temporarily reduced by opening the on-off valve of the bypass circuit for a predetermined time. In addition, the saturation temperature (evaporation pressure) of the refrigerant can be increased. By repeating this until the saturation temperature exceeds the lower limit, freezing of the cooling liquid in the subcooler can be prevented.

Eighth means comprises a refrigeration cycle comprising at least a compressor, a four-way valve, an outdoor heat exchanger, an expansion mechanism and a subcooler connected to each other, and a cooling liquid supercooled by the subcooler. An ice heat storage tank for storing the generated ice and cooling liquid, a cooling liquid circuit connecting the ice heat storage tank and the subcooler, and a circulation circuit for circulating the cooling liquid through the cooling liquid circuit. An ice heat storage unit having a coolant pump, and control means for controlling switching between cooling or ice making operation and heating operation of the refrigeration cycle by the four-way valve and heating operation, and controlling the coolant pump. When the freezing occurs in the subcooler, the freeze-release operation of temporarily switching the four-way valve and stopping the operation of the coolant pump to perform the heating operation of the refrigeration cycle is performed. It is ice heat storage device according to claim.

According to the eighth means, the four-way valve is switched so that the refrigeration cycle is set to the heating operation, and the operation of the coolant pump is stopped, so that the hot gas from the compressor is used with the outdoor heat exchanger as the evaporator. Can heat the subcooler.

A ninth means is the control means according to the eighth means, wherein the control means temporarily operates the coolant pump when performing the freeze releasing operation.

According to the ninth means, in the eighth means, the coolant heated by the hot gas in the subcooler is operated by operating the coolant pump during the freeze releasing operation. From the cooling liquid circuit to the ice storage tank
Ice nuclei from the supercooler to the cooling liquid circuit to the ice heat storage tank can be completely removed. For this reason, when returning from ice release to ice making operation, the ice making operation can be performed with the influence of freezing completely removed.

Tenth means is the eighth means, wherein the control means is adapted to execute the freeze-freeing operation when the inside of the subcooler again freezes within a predetermined time after the freezing-free operation is performed. After that, the ice making operation for generating ice from the cooling liquid is terminated.

According to the tenth aspect, in the eighth aspect, if the freezing occurs again in the supercooler within a predetermined time after performing the freeze releasing operation, the volume of the ice in the ice heat storage tank is reduced. Judging that ice is accumulating to the allowable amount, performing the freeze release operation again, and terminating the ice making operation, the ice making operation is terminated before the ice exceeding the allowable amount of the ice heat storage tank is accumulated. Thus, safe and reliable operation can be ensured.

An eleventh means is the ice amount detecting means for detecting that the volume of ice accumulated in the ice heat storage tank has reached a predetermined allowable amount in any one of the first to tenth means. Means for detecting the amount of ice that has reached a predetermined allowable amount, and terminating the ice making operation for generating ice from the cooling liquid when the ice amount detecting means detects that the volume of the ice has reached a predetermined allowable amount. It is.

According to the eleventh means, the first to the first
0, the ice making operation is terminated when the ice amount detecting means detects that the volume of ice accumulated in the ice heat storage tank has reached a predetermined allowable amount. The ice making operation is terminated before the ice exceeding the allowable amount accumulates, and safe and reliable operation can be ensured.

The twelfth means is the eleventh means,
The ice amount detecting means is provided above the liquid level of the cooling liquid on a side surface of the ice heat storage tank, and an inlet pipe for introducing a cooling liquid eluted from ice in the ice heat storage tank; And a temperature sensor for detecting the coolant introduced into the apparatus.

The thirteenth means is an ice heat storage tank for accumulating ice and cooling liquid generated from the supercooled cooling liquid, and is provided on one side of the ice heat storage tank to store the cooling liquid. A subcooler for cooling to a supercooled state, a jetting unit provided at one side of the ice heat storage tank for jetting the supercooled cooling liquid, and an ice heat storage tank. A supercooling release plate having a water intake port, the supercooling release plate being provided on the side of the subcooling device for colliding the coolant jetted from the jetting portion to release the supercooled state thereof; And a cooling liquid pipe for guiding a cooling liquid taken in from an intake port to one side of the ice heat storage tank, wherein the cooling liquid pipe is provided in the ice heat storage tank. Device.

According to the thirteenth means, since the coolant pipe is provided in the ice heat storage tank, the space required for the pipe can be reduced as compared with a case where the cooling liquid pipe is bypassed outside the ice heat storage tank. .

The fourteenth means is the thirteenth means,
Ice amount detecting means for detecting that the volume of the ice has reached a predetermined allowable amount by contact of the ice accumulated in the ice heat storage tank is provided in the cooling liquid pipe, and the ice amount detecting means is provided. Is configured to terminate an ice making operation for generating ice from the cooling liquid when detecting that the ice reaches a predetermined allowable amount.

According to the fourteenth means, in the thirteenth means, when the ice amount detecting means detects that the volume of ice accumulated in the ice heat storage tank has reached a predetermined allowable amount, the ice making is performed. By terminating the operation, the ice making operation can be terminated before the ice exceeding the allowable amount of the ice heat storage tank accumulates, thereby ensuring safe and reliable operation.

The fifteenth means is the fourteenth means,
The ice amount detecting means is provided on the subcooling release plate.

The sixteenth means is the thirteenth means,
The spouting section is provided so as to protrude into the ice heat storage tank, and a barrier member is provided below the spouting section to prevent rise of ice in the ice heat storage tank.

According to the sixteenth means, in the thirteenth means, even if the ice in the ice heat storage tank approaches the spout, the barrier prevents the ice from reaching the spout. be able to.

The seventeenth means is the sixteenth means,
The barrier member has a wedge-shaped cross-sectional shape that expands upward.

According to the sixteenth aspect, in the sixteenth aspect, the ice rising toward the jetting portion can be deflected from the jetting portion by the barrier portion, so that the ice reaches the jetting portion. It can be reliably prevented.

[0049] The eighteenth means may be the ice storage device according to the sixteenth or seventeenth means, for detecting that the volume of the ice reaches a predetermined allowable amount due to contact of the ice accumulated in the ice heat storage tank. An amount detecting means is provided at the bottom of the barrier member, and when the ice amount detecting means detects that the ice reaches a predetermined allowable amount, the ice making operation for generating ice from the cooling liquid is ended. It is configured as follows.

According to the eighteenth means, in the sixteenth or seventeenth means, when the ice amount detecting means detects that the volume of ice accumulated in the ice heat storage tank has reached a predetermined allowable amount. In addition, by terminating the ice making operation, the ice making operation can be terminated before the ice exceeding the allowable amount of the ice heat storage tank accumulates, thereby ensuring safe and reliable operation.

According to a nineteenth aspect, in any one of the thirteenth to eighteenth aspects, a filter for preventing ice from entering the water intake of the subcooling release plate is provided.

According to the nineteenth means, in any one of the thirteenth to eighteenth means, the filter provided in the water intake prevents the ice in the ice heat storage tank from entering the water intake. Blockage of the coolant pipes and the like due to the entry of ice can be prevented.

The twentieth means is an ice storage air conditioning system comprising an outdoor unit, an ice storage unit and an indoor unit, wherein at least a compressor, an outdoor heat exchanger, an expansion mechanism, an indoor heat exchanger and a subcooler are provided. The outdoor unit has at least the outdoor heat exchanger, and the ice heat storage unit includes at least the subcooler and a cooling unit in a supercooled state by the subcooler. An ice heat storage tank for accumulating ice and cooling liquid generated from the liquid, the indoor unit having at least the indoor heat exchanger, and a valve mechanism provided in the refrigerant circuit; The ice storage air conditioning system is configured so that air conditioning operation can be performed only by the outdoor unit and the indoor unit by switching.

According to the twentieth means, even if the ice heat storage unit fails, the switching of the valve mechanism allows
The air conditioning operation can be performed only by the outdoor unit and the indoor unit.

[0055]

Next, an embodiment of the present invention will be described with reference to the drawings. 1 to 23 are views showing an embodiment of an ice heat storage device and an ice heat storage air conditioning system according to the present invention. In the embodiment of the present invention shown in FIGS. 1 to 23, the same components as those in the conventional example shown in FIGS.

[First Embodiment] First, FIG. 1 and FIG.
The first embodiment of the present invention will be described with reference to FIG. FIG.
In the ice heat storage device, the compressor 1, the outdoor heat exchanger 2,
A refrigeration cycle is provided in which an expansion valve (expansion mechanism) 3 and a subcooler 4 are sequentially connected by a refrigerant circuit 5. Further, the ice heat storage device includes an ice heat storage tank 10 for storing ice I and cooling liquid L generated from the cooling liquid L ′ supercooled by the subcooler 4. Note that water or an aqueous solution is used as the cooling liquids L and L '.

One side of the ice heat storage tank 10 has a subcooler 4
A jet portion 14 for jetting the cooling liquid L ′ from the tank is provided, and the cooling liquid L ′ jetted from the jetting portion 14 collides with the other side of the ice heat storage tank 10 to release the supercooled state. A supercooling release plate 12 is provided. Also,
A coolant pump 20 and a coolant circuit 21 for sending the coolant L in the ice heat storage tank 10 to the supercooler 4 are provided. In addition, these ice thermal storage tanks 10, the spouting section 14,
Subcooling release plate 12, coolant pump 20, coolant circuit 21
And the subcooler 4 constitute an ice heat storage unit (however,
The supercooler 4 also forms a part of the refrigeration cycle).

When an ice making operation is performed with this ice heat storage device,
The compressor 1 and the coolant pump 20 are operated. Then, the high-temperature and high-pressure refrigerant discharged from the compressor 1 is condensed in the outdoor heat exchanger 2, then decompressed by the expansion valve 3, exchanges heat with the cooling liquid L in the supercooler 4, and evaporates. At this time, the coolant L (for example, 0 ° C.) sent to the supercooler 4 by the coolant pump 20 is cooled to a supercooled state (for example, −2 ° C.).

The cooling liquid (flowing subcooling liquid) L ′ cooled to the supercooled state is supplied to the jetting portion 14 on one side of the ice heat storage tank 10.
And collides with the subcooling release plate 12 on the other side. Then, the supercooled state of the cooling liquid L ′ is released by the impact of the collision, and ice in a slurry state and the cooling liquid L at a freezing point (for example, 0 ° C.) are generated. Then, by continuing such an operation, ice in the form of slurry is accumulated in the ice heat storage tank 10.

Next, the ice heat storage device is provided with control means C for controlling the number of revolutions of the compressor 1. At the outlet side of the subcooler 4, a coolant temperature detector 22 for detecting the degree of supercooling .DELTA.T1 of the coolant L 'and a pressure detector 6p for detecting the evaporation pressure of the refrigerant are provided. ing. Here, the degree of supercooling ΔT1 of the cooling liquid L 'refers to a difference between the temperature of the cooling liquid L' at the outlet side of the subcooler 4 and the freezing point of the cooling liquid L (for example, when the cooling liquid L is water (freezing point 0 ° C.), and when the temperature of the coolant L ′ at the outlet side of the cooler 4 is −2 ° C., the degree of supercooling ΔT1 of the coolant L ′ is −2 K).

The control means C controls the degree of supercooling .DELTA.T1 of the coolant L 'detected by the coolant temperature detector 22.
And the saturation temperature Ts of the refrigerant corresponding to the evaporation pressure detected by the pressure detector 6p.
Is controlled to temporarily reduce the rotational speed of the compressor 1 when the lower limit reaches a preset lower limit value according to the degree of supercooling ΔT1 of the cooling liquid L ′.

More specifically, as shown in FIG. 3, for example, the range of the degree of supercooling ΔT1 of the cooling liquid L 'is set to a predetermined value T1 and T2.
(T1> T2), ΔT1 ≧ T1, T1> ΔT1
> T2, T2 ≧ ΔT1, the lower limit values T3, T4, T5 of the saturation temperature Ts (where T3 <
T4 <T5) is set. That is, the lower limit value of the saturation temperature Ts of the refrigerant used in the above control is set so as to increase as the degree of supercooling ΔT1 of the coolant L ′ decreases (the absolute value of the degree of supercooling ΔT1 increases). .
In the "control conditions" of FIG. 3, expressions such as "Ts>T3" are used to mean that the control is performed so that the saturation temperature Ts does not reach the lower limit values T3, T4, and T5.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, since the saturation temperature Ts (evaporation pressure) of the refrigerant can be increased by temporarily lowering the rotation speed of the compressor 1, the above-described control is performed during the ice making operation. By
The freezing of the coolant L 'in the supercooler 4 can be prevented by preventing the saturation temperature Ts (evaporation pressure) of the coolant from lowering more than necessary according to the degree of supercooling ΔT1 of the coolant L'. .

In the present embodiment, the lower limit value of the saturation temperature Ts of the refrigerant used for the above control is set so as to increase as the degree of supercooling ΔT1 of the coolant L ′ decreases. The saturation temperature Ts (evaporation pressure) can be maintained higher as the cooling liquid .DELTA.T1 is lower and the cooling liquid L 'is more unstable, and the supercooling degree .DELTA.T1 itself can be controlled so as not to be reduced more than necessary. For this reason, the subcooler 4
In this case, it is possible to stably and continuously generate the supercooled cooling liquid L 'while avoiding freezing.

The control according to the present embodiment is also effective when the suction pressure of the compressor 1 drops rapidly, such as when the outside air temperature changes suddenly, when rain starts to fall, or when the wind is strong.

[Second Embodiment] Next, FIGS.
The second embodiment of the present invention will be described with reference to FIG. FIG.
As shown in FIG. 7, the present embodiment is different from the first embodiment in that an electric control valve 3a is provided as an expansion mechanism of a refrigeration cycle, and a control unit C1 further controls the opening of the electric control valve 3a. Is similar to that of the first embodiment shown in FIG.

That is, in the present embodiment, the control means C1 controls the degree of supercooling .DELTA.T1 of the coolant detected by the coolant temperature detector 22 and the degree of cooling of the refrigerant corresponding to the evaporation pressure detected by the pressure detector 6p. Based on the saturation temperature Ts, when the saturation temperature Ts reaches a lower limit preset in accordance with the degree of supercooling ΔT1 of the coolant L ', the electric control valve 3
The control for temporarily increasing the opening degree of “a” is performed. in this case,
The specific control is performed by the setting as shown in FIG. 3, for example, as in the case of the first embodiment.

In the above control, the electric control valve 3
The amount of change in the opening of a may be a fixed amount, or may be changed according to the degree of supercooling ΔT1 of the cooling liquid L 'and the saturation temperature Ts (evaporation pressure) of the refrigerant.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, the saturation temperature Ts (evaporation pressure) of the refrigerant can be increased by temporarily increasing the opening of the electric control valve 3a.
By performing the above-described control during the ice making operation, it is possible to achieve the same functions and effects as those of the first embodiment.

In this embodiment, not only the control of the opening of the electric control valve 3a described above but also the control of the rotation speed of the compressor 1 in the first embodiment described above is combined. Or both controls may be performed.

[Third Embodiment] Next, FIG. 4 and FIG.
The third embodiment of the present invention will be described with reference to FIG. FIG.
As shown in FIG. 5, in the present embodiment, a refrigerant temperature detector 6t for detecting the refrigerant temperature at the outlet side of the subcooler 4 is provided, and the control means C2 determines the saturation temperature Ts of the refrigerant and the saturation temperature of the refrigerant. Compressor 1 based on the degree of superheat ΔT2 which is the difference between Ts and the refrigerant temperature detected by refrigerant temperature detector 6t.
The second embodiment differs from the second embodiment in that the number of rotations or the opening of the electric control valve 3a is controlled, and the other configuration is the same as that of the second embodiment shown in FIG.

More specifically, as shown in FIG. 5, the control means C2 determines that the superheat degree ΔT2 of the refrigerant reaches a predetermined upper limit a (S1) and the saturation temperature Ts of the refrigerant is as shown in FIG. When the preset lower limit value is reached, control is performed such that the rotation speed of the compressor 1 is temporarily reduced or the opening of the electric control valve 3a is temporarily increased (S2).

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, the supercooler 4 avoids a state in which the region where the coolant L 'is placed in the supercooled state due to an increase in the degree of superheat ΔT2 of the refrigerant becomes too large, and the cooling of the coolant L' is prevented. Can be controlled so as to end near the outlet of the supercooler 4 as much as possible. Therefore, the possibility of freezing of the cooling liquid L 'in the subcooler 4 can be reduced.

As shown in FIG. 6, as a criterion for the above-described control, a time change rate (an increase per unit time) of the superheat degree ΔT2 is used instead of the superheat degree ΔT2 of the refrigerant. When the time rate of change of the degree of superheat ΔT2 reaches the predetermined upper limit b and the saturation temperature Ts of the refrigerant reaches the lower limit (S3), the rotational speed of the compressor 1 is temporarily reduced, or The same operation and effect can be achieved by performing control such that the opening of the control valve 3a is temporarily increased (S4).

[Fourth Embodiment] Next, a fourth embodiment of the present invention will be described with reference to FIG. As shown in FIG. 7, in the present embodiment, in the control of the first to third embodiments, when the freezing frequency Ff of the coolant in the subcooler 4 reaches a predetermined upper limit c, the refrigerant Saturation temperature T
The second embodiment differs from the first to third embodiments in that the lower limit L1 of s (the value corresponding to T3, T4, and T5 in FIG. 3) is changed. This is the same as any of the first to third embodiments shown in FIG.

More specifically, as shown in FIG. 7, for example, the lower limit value of the saturation temperature Ts at the start of the ice making operation is set to an initial value L1 (n = 0 at this time) (S5), and The freezing frequency Ff of the coolant in the cooler 4 is equal to a predetermined upper limit c.
Is exceeded (S6), n = n + 1 (S7), and the lower limit of the saturation temperature Ts is increased to L1 = L1 + n × ΔS (S8). That is, until the freezing frequency Ff falls below the predetermined upper limit c, the lower limit L1 of the saturation temperature Ts is changed from the initial value by 1 from the initial value.
Control is performed so as to increase step by step ΔS.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, in the control of the first to third embodiments, the lower limit value L1 of the saturation temperature Ts of the refrigerant is set such that the freezing frequency Ff of the coolant in the subcooler 4 is equal to or less than the predetermined upper limit value c. Therefore, the effect of preventing freezing by the control of the first to third embodiments can be improved. Further, it is possible to suppress the occurrence of freezing due to the variation in the detection error of the pressure detector 6p for each device.

[Fifth Embodiment] Next, FIGS.
The fifth embodiment of the present invention will be described with reference to FIG. FIG.
As shown in FIG. 9 and FIG. 9, in the present embodiment, a bypass circuit 7 having an on-off valve 7v bypassing the subcooler 4 in the refrigeration cycle is provided. The first and second embodiments are different from the first and second embodiments in that the on-off valve 7v of the bypass circuit 7 is configured to be temporarily opened when L1 is reached. This is the same as the second embodiment.

Specifically, as shown in FIG. 9, when the saturation temperature Ts of the refrigerant reaches the lower limit L1 (set in accordance with the degree of supercooling ΔT1) (S9), the bypass circuit 7 The opening / closing valve 7v is opened for a predetermined time (S10), and this is repeated until the saturation temperature Ts exceeds the lower limit L1 (S9 → S10
→ S9) is repeated.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, the flow rate of the refrigerant to the subcooler 4 is temporarily reduced by opening the on-off valve 7v of the bypass circuit 7 for a predetermined time, and the saturation temperature Ts (evaporation pressure) of the refrigerant is increased. Can be. By repeating this until the saturation temperature Ts exceeds the lower limit L1, the cooling liquid in the subcooler 4 can be prevented from freezing. The present embodiment is particularly effective in preventing freezing when the evaporation pressure of the refrigerant suddenly drops due to unpredictable disturbance such as a gust.

[Sixth Embodiment] Next, a sixth embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 10, in the present embodiment, a refrigeration cycle includes a four-way valve 8, a refrigerant flow control valve 9, and a liquid-side refrigerant for detecting the refrigerant temperature on the liquid side (expansion valve 3 side) of the supercooler 4. A temperature detector 6t 'is provided, and a control means (not shown) switches between the cooling or ice making operation and the heating operation of the refrigeration cycle by the four-way valve 8 and the coolant pump 20.
The second embodiment is different from the first embodiment in that the second embodiment is configured to control the operation of the first embodiment. Other configurations are the same as those of the first embodiment shown in FIG. In FIG. 10, solid arrows indicate the direction of refrigerant flow during cooling or ice making operation.
The dashed arrows indicate the direction of the refrigerant flow during the heating operation (freezing release operation).

More specifically, the control means includes a subcooler 4
When the cooling liquid L 'freezes inside, the four-way valve 8 is temporarily switched so that the refrigeration cycle is set to the heating operation, and the operation of the cooling liquid pump 20 is stopped (the compressor 1).
Do not stop) Perform the freeze release operation. That is, FIG.
As shown in FIG. 1, when the freezing of the subcooler is detected during the ice making operation (S20), the above-described freezing release operation is performed, whereby the outdoor heat exchanger 2 is used as an evaporator and supercooled by hot gas from the compressor 1. The inside of the vessel 4 is heated (S21). At this time, the expansion valve 3 is opened, and the refrigerant is depressurized by the flow control valve 9.

If the refrigerant temperature TL detected by the liquid-side refrigerant temperature detector 6t 'exceeds a predetermined set value B1 during execution of the freeze release operation (S22), the subcooler 4 It is determined that the heating has been sufficiently performed and the freezing has been released, the refrigeration cycle is switched to the ice making operation by the four-way valve 8, the coolant pump 20 is operated, and the operation returns to the ice making operation (S23).

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, the four-way valve 8 is switched so that the refrigeration cycle becomes the heating operation, and the operation of the coolant pump 20 is stopped, so that the freeze release operation can be performed without stopping the compressor 1. , Compared to conventional equipment that temporarily stops the refrigerator or uses multiple subcoolers, the configuration is simpler,
In addition, it is possible to quickly return from the freeze release to the ice making operation.

When returning to the ice making operation described above (S2
In 3), when the opening degree of the expansion valve 3 is detected as freezing (S20)
By slightly controlling the opening degree in the above, the time from the return of the ice making operation to the start of the actual ice making can be further reduced. Also, when switching the four-way valve 8, the switching resistance can be reduced by switching after the rotation speed of the compressor 1 is reduced to some extent.

[Seventh Embodiment] Next, FIG. 10 and FIG.
2, a seventh embodiment of the present invention will be described. As shown in FIG. 12, the present embodiment differs from the sixth embodiment in that the control means operates the coolant pump 20 temporarily when performing the freeze release operation. Of the sixth embodiment shown in FIGS. 10 and 11.
This is the same as the embodiment.

More specifically, as shown in FIG. 12, when the freezing of the subcooler 4 is detected during the ice making operation (S24), the four-way valve 8 is temporarily switched so that the refrigeration cycle is set to the heating operation. The operation is the same as that of the sixth embodiment shown in FIG. 11 up to the point where the operation of the coolant pump 20 is stopped (S21) to perform the freezing release operation using hot gas.

In the present embodiment, the refrigerant temperature TL detected by the liquid-side refrigerant temperature detector 6t 'is set to the predetermined set value B during the execution of the freeze release operation using the hot gas.
If it exceeds 2 (S26), the coolant pump 20 is operated for a fixed time (N seconds) (S27). After the operation of the coolant pump 20, the temperature of the refrigerant in the subcooler 4 temporarily drops. However, since the heating in the subcooler 4 is continuously performed by the hot gas, the refrigerant temperature T
L rises. When the refrigerant temperature TL rises and exceeds the predetermined set value B2 (S28), the refrigeration cycle is switched to the ice making operation by the four-way valve 8, the coolant pump 20 is operated, and the operation returns to the ice making operation (S29). .

In the present embodiment, the value of the refrigerant temperature TL detected by the liquid-side refrigerant temperature detector 6t 'is used as a criterion for returning to the ice making operation from the freeze release operation.
Instead, the temperature of the coolant at the inlet of the supercooler 4 or the outlet 14 is detected, and when the temperature of the coolant exceeds a predetermined set value, the operation is returned from the freeze release operation to the ice making operation. Is also good. Also, the case where the operation of the coolant pump 20 is performed only once during the freeze release operation has been described, but this may be performed a plurality of times.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, in the sixth embodiment, by operating the coolant pump 20 during the freeze releasing operation, the coolant heated by the hot gas in the subcooler 4 is cooled by the subcooler 4. From the supercooler 4 to the jetting portion 14 to completely remove the ice nuclei. For this reason, when returning from ice release to ice making operation, the ice making operation can be performed with the influence of freezing completely removed.

[Eighth Embodiment] Next, an eighth embodiment of the present invention will be described with reference to FIGS.
This embodiment is different from the sixth or seventh embodiment in that it switches between the ice making operation and the freeze release operation as shown in the time chart of FIG. The sixth or seventh embodiment shown in FIGS.
This is the same as the embodiment.

Here, FIG. 13 shows the process of forming the ice I in the ice heat storage tank 10 for each stage. In FIG. 13, the generated slurry-like ice I floats on the surface of the cooling liquid L by buoyancy in the initial stage of ice making (STEP).
-A) Due to the deposition from above, the cooling liquid L is gradually deposited below the liquid level (STEP-B). When the ice making operation is further continued, the filling space below the liquid level is lost, and the ice I accumulates on the liquid level (S
TEP-C). And if you continue the ice making operation as it is,
The ice I accumulates near the ejection part 14 (STEP-D), and finally the ejection part 14 is closed by the ice I exceeding the allowable amount of the ice heat storage tank 10.

Therefore, in this embodiment, as shown in FIG. 14, when the freezing of the subcooler 4 is detected during the ice making operation (S
31) After performing the freeze release operation as described in the sixth or seventh embodiment (S32), the process returns to the ice making operation (S33). Then, after returning to the ice making operation, when the freezing is detected again (S34), the previous freezing detection (S34) is performed.
When the elapsed time t1 from 31) is equal to or less than the predetermined set value tm, it is determined that the ice I has accumulated near the ejection section 14 as in STEP-D in FIG. (S35) to end the ice making operation.

Incidentally, two freeze detections (S31, S34)
Although the case where the ice making operation is terminated based on the time interval of the above has been described, the ice making operation may be terminated based on the time interval of three or more freeze detections as shown by a broken line in FIG.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, it is difficult to grasp the amount of generated ice in the ice heat storage tank 10.
In the apparatus according to the above, the ice making operation is terminated before the jetting section 14 is closed by the ice I exceeding the allowable amount of the ice heat storage tank 10 by the above-described control, thereby ensuring safe and reliable operation. Can be.

[Ninth Embodiment] Next, a ninth embodiment of the present invention will be described with reference to FIGS.
In the present embodiment, as shown in FIGS. 15 and 16, a flapper switch (ice amount detecting means) 24 for detecting the amount of ice is provided in the ice heat storage tank 10, and the flapper switch 24 is provided in the ice heat storage tank 10. The first embodiment is different from the first to seventh embodiments in that the ice making operation is ended when it is detected that the volume of the ice I has reached a predetermined allowable amount. 12 to FIG. 12 are the same as those in any of the first to seventh embodiments.

The flapper switch 24 is, as shown in FIG.
It is provided between the level of the cooling liquid L in the nozzle 0 and the jetting section 14. As shown in FIG. 16, the flapper switch 24 has a flapper section 24a and a contact section 24b.
Then, the flapper section 24a normally keeps a posture protruding substantially horizontally in the ice heat storage tank 10 (FIG. 16A), but the ice I in the ice heat storage tank 10 accumulates near the ejection section 14. Then, it is pushed by the ice I to swing upward to the contact portion 24b, and finally contacts the contact portion 24b to turn on the flapper switch 24 (FIG. 16B).

When the flapper switch 24 is turned on, the ice heat storage device of this embodiment determines that the volume of the ice I in the ice heat storage tank 10 has reached a predetermined allowable amount, and stops the ice making operation. It is configured to be. Although the case where the flapper switch 24 is installed on one side surface of the ice heat storage tank 10 has been described, a similar flapper switch 24 may be installed downward from the ceiling of the ice heat storage tank 10.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, it is difficult to grasp the amount of generated ice in the ice heat storage tank 10.
In the apparatus according to the above, the ice amount detection by the flapper switch 24 as described above terminates the ice making operation before the jetting section 14 is closed by the ice I exceeding the allowable amount of the ice heat storage tank 10, thereby ensuring safe and reliable operation. Operation can be secured.

[Tenth Embodiment] Next, a tenth embodiment of the present invention will be described with reference to FIGS. In the present embodiment, as shown in FIGS.
An ice amount detection unit (ice amount detection means) 26 is provided in place of the flapper switch 24 of the ninth embodiment, and the other configuration is the same as that of the ninth embodiment.

In FIG. 17 and FIG. 18, the ice amount detecting section 26 is provided on one side of the ice heat storage tank 10 with an introduction pipe 26 projecting outward from between the liquid level of the cooling liquid L and the jetting section 14.
a. Further, the ice amount detecting means 26 is provided in the introduction pipe 2.
It has a tray 26b arranged below the tip of 6a, and a temperature sensor 26c inserted in the tray 26b.

As shown in FIG. 18, when the ice I in the ice heat storage tank 10 accumulates near the jetting portion 14 and reaches the height of the introduction pipe 26a, the ice water-like cooling liquid L ″ eluted from the ice I is introduced. After flowing into the pipe 26a, it falls into the tray 26b from the distal end of the introduction pipe 26a.The temperature sensor 26c normally detects the ambient air temperature, but the cooling liquid L ″ falling into the tray 26b Upon contact, the temperature is detected. When the temperature sensor 26c detects the temperature of the cooling liquid L ″, the ice heat storage device according to the present embodiment includes the ice I in the ice heat storage tank 10.
Is determined to have reached a predetermined allowable amount, and the ice making operation is stopped.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, it is difficult to grasp the amount of generated ice in the ice heat storage tank 10.
In the device according to the above, the ice amount detecting means 26 as described above is also used.
, The ice making operation can be terminated before the jetting section 14 is closed by the ice I exceeding the allowable amount of the ice heat storage tank 10, thereby ensuring safe and reliable operation.

In the ninth and tenth embodiments described above, the ejection section 1 provided on one side of the ice heat storage tank 10 is used.
Although the description has been given of the ice heat storage device configured to eject the cooling liquid L ′ from FIG. 4 substantially horizontally, the same effect can be obtained even in a configuration in which the cooling liquid L ′ is ejected from above.

[Eleventh Embodiment] Next, an eleventh embodiment of the present invention will be described with reference to FIGS. This embodiment is different from the first to seventh embodiments in that an ice heat storage tank 10 'as shown in FIG. 19 is provided in place of the ice heat storage tank 10, and other configurations are shown in FIGS. This is substantially the same as any of the first to seventh embodiments.

As shown in FIGS. 19 and 20, the ice heat storage tank 10 'is provided with the subcooler 4 outside the upper surface of one side surface 10a. The ejection portion (ejection nozzle) 14 extends through the interior. In addition, a penetrating portion on one side surface 10 a of the ejection portion 14 is sealed by a sealing material 15.

Further, as shown in FIG.
A subcooling release plate 12 'is provided inside the other side surface 10b of 0'. An intake port 12 for taking in the cooling liquid in the ice heat storage tank 10 ′ is provided below the supercooling release plate 12 ′.
a is formed. The water inlet 12a is provided with a filter for preventing ice from entering the ice heat storage tank 10 '.

A cooling liquid pipe 16 for guiding the cooling liquid introduced from the water inlet 12a of the supercooling release plate 12 'to one side surface 10a of the ice heat storage tank 10' is provided at the bottom of the ice heat storage tank 10 '. Is provided. The cooling liquid pipe 16 penetrates one side surface 10a of the ice heat storage tank 10 ', extends outside the one side surface 10a, and is connected to the subcooler 4. In FIG. 19, reference numeral 17 denotes a coolant pumping means (corresponding to the coolant pump 20) for pumping the coolant taken in from the water inlet 12a of the supercool release plate 12 'to the supercooler 4. You do).

Also, as shown in FIGS. 20 and 21,
Inside the one side surface 10a of the ice heat storage tank 10 ', a barrier member 18 for preventing the rise of the ice I in the ice heat storage tank 10' is provided below the jetting portion 14. This barrier member 1
8 has a wedge-shaped cross-sectional shape that expands upward (see FIG. 21). Here, the protrusion length l2 of the barrier member 18 from one side surface 10a of the ice heat storage tank 10 'is preferably longer than the protrusion length l1 of the jetting portion.

On the bottom of the barrier member 18, there is provided an ice amount detecting means for detecting that the volume of the ice I has reached a predetermined allowable amount due to the contact of the ice I accumulated in the ice heat storage tank 10 '. 18s are provided. The ice heat storage device of the present embodiment is configured to end the ice making operation when the ice amount detecting means 18s detects that the ice I has reached the allowable amount.

Incidentally, instead of the ice amount detecting means 18s provided at the bottom of the barrier member 18, the subcooling release plate 1
The ice amount detecting means 12s provided at 2 'or the ice amount detecting means 16s provided at the cooling liquid pipe 16 may be used.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, since the cooling liquid pipe 16 is provided in the ice heat storage tank 10 ', space saving can be achieved as compared with the case where the cooling liquid pipe 16 is bypassed outside the ice heat storage tank 10'. Also, the subcooling release plate 1
Since the filter for preventing the entry of ice in the ice heat storage tank 10 'is attached to the intake port 12a of 2', it is possible to prevent the cooling liquid piping 16 and the like from being blocked due to such entry of ice. .

The ice amount detecting means 18s (or 12s,
By detecting the amount of ice in 16s), the ice making operation can be ended before the ejection unit 14 is closed by the ice I exceeding the allowable amount of the ice heat storage tank 10 ', and safe and reliable operation can be ensured. Furthermore, even when the ice I in the ice heat storage tank 10 ′ approaches the ejection section 14, the ice section I can be reliably prevented from reaching the ejection section 14 by the barrier section 18.

[Twelfth Embodiment] Next, a twelfth embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 22, the present embodiment includes an outdoor unit A and an ice heat storage unit U which constitute an ice heat storage device substantially similar to the ice heat storage device of the sixth embodiment shown in FIG. An ice storage air conditioning system including a plurality of indoor units B connected to U. Therefore, the same components as those of the ice heat storage device of the sixth embodiment shown in FIG. 10 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 22, the plurality of indoor units B are connected to a refrigerant circuit 5a branched from the refrigerant circuit 5 so as to bypass the supercooler 4 of the ice heat storage unit U. Each of these indoor units B has an indoor heat exchanger 30
And an expansion valve 32. Ice storage unit U
, An electromagnetic two-way valve (valve mechanism) V1 is interposed in a refrigerant circuit 5a branching from the inlet side of the supercooler 4 (on the front side of the electric control valve 3a) and heading to the indoor unit B. An electromagnetic two-way valve V2 is provided in the refrigerant circuit 5 on the outlet side of the vessel 4. Further, the ice heat storage unit U includes a use-side heat exchanger 23 for exchanging heat between the coolant L and the refrigerant on the inlet side of the subcooler 4. In FIG. 22, reference numeral 33 denotes a gas-liquid separator, and reference numeral 34 denotes a liquid receiver.

Next, FIG. 23 schematically shows a system configuration of a control system in the ice storage air conditioning unit of the present embodiment. In FIG. 23, the ice heat storage unit U includes a control unit (MCU) 35, and a coolant temperature sensor or a refrigerant temperature sensor (not shown) of each unit is connected as an input 36 to the control unit 35, and an output is provided. 37, the two-way valves V1, V2, the coolant pump 20, and the electric control valve (PM
V) 3a etc. are connected. The control unit 35 includes
The outdoor unit A and each indoor unit B are sequentially connected, and an ice heat storage remote controller 38 connected to a weekly timer 39 is connected. The remote controller 38 can operate the air conditioning system.

In the air conditioning system, when performing the ice making operation, the two-way valve V1 is closed and the two-way valve V2 is opened.
When the operation is performed only by the outdoor unit A and the ice heat storage unit U and the cooling operation using the ice heat storage is performed, the two-way valve V
1, the two-way valve V2 is closed, and the outdoor unit A, the ice heat storage unit U, and each indoor unit B are operated. In the latter case, in the use side heat exchanger 23,
The refrigerant from the outdoor heat exchanger 2 is cooled by the cooling liquid L taken out from the ice heat storage tank 10, and the cooling capacity is increased.

Here, the air conditioning system of the present embodiment opens the outdoor unit by forcibly opening the two-way valve V1 even when the two-way valve V1 remains closed due to the failure of the ice heat storage unit U. The air conditioning operation (normal cooling operation or heating operation) can be performed only by A and the indoor unit B. In this case, as means for forcibly opening the two-way valve V1, other than means for automatically opening the two-way valve V1 in response to the failure of the ice heat storage unit U,
And a unit that is opened by operating a manual operation switch or the like provided in the control unit 35 or a unit that is opened by connecting another system power supply to the two-way valve V1.

Next, the operation and effect of this embodiment having the above configuration will be described. According to the present embodiment, even when the two-way valve V1 remains closed due to the failure of the ice heat storage unit U, the two-way valve V1 is forcibly opened, so that only the outdoor unit A and the indoor unit B are used. Since the configuration is such that the air-conditioning operation can be performed, the user can use the air-conditioning even until the failure of the ice heat storage unit U is corrected.

[0120]

According to the invention as set forth in claims 1 to 7, 11 and 12, the supercooling is performed by not lowering the saturation temperature (evaporation pressure) of the refrigerant more than necessary according to the degree of supercooling of the coolant. According to the invention of claims 8 to 12, which can prevent freezing of the coolant in the vessel, by switching the four-way valve so that the refrigeration cycle performs the heating operation and stopping the operation of the coolant pump, The inside of the subcooler can be heated by hot gas from the compressor. For this reason, since the defrosting operation can be performed without stopping the compressor, the configuration is simpler than that of the conventional apparatus in which the refrigerator is temporarily stopped or a plurality of supercoolers are used, and the defrosting operation is performed. It is possible to quickly return to the ice making operation.

According to the invention of claims 13 to 19,
Since the cooling liquid pipe is provided in the ice heat storage tank, the space required for the pipe can be reduced as compared with the case where the outside of the ice heat storage tank is bypassed. For this reason, downsizing of the device,
Simplification can be achieved.

According to the twentieth aspect, even when the ice heat storage unit is out of order, the air conditioning operation can be performed only by the outdoor unit and the indoor unit by switching the valve mechanism. Therefore, the user can use the air conditioner until the failure of the ice heat storage unit is corrected.

[Brief description of the drawings]

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

FIG. 2 is a block diagram showing a second embodiment of the ice heat storage device according to the present invention.

FIG. 3 is a chart showing control in the ice heat storage device shown in FIGS. 1 and 2;

FIG. 4 is a block diagram showing a third embodiment of the ice heat storage device according to the present invention.

5 is a flowchart showing control in the ice heat storage device shown in FIG.

6 is a flowchart showing another control in the ice heat storage device shown in FIG.

FIG. 7 is a flowchart illustrating control in a fourth embodiment of the ice heat storage device according to the present invention.

FIG. 8 is a block diagram showing a fifth embodiment of the ice heat storage device according to the present invention.

9 is a flowchart showing control in the ice heat storage device shown in FIG.

FIG. 10 is a block diagram showing a sixth embodiment of the ice heat storage device according to the present invention.

11 is a flowchart showing control in the ice heat storage device shown in FIG.

FIG. 12 is a flowchart showing control in an ice heat storage device according to a seventh embodiment of the present invention.

FIG. 13 is a schematic longitudinal sectional view showing progress of accumulation of ice in an ice heat storage tank in an eighth embodiment of the ice heat storage device according to the present invention.

FIG. 14 is a time chart showing control in an eighth embodiment of the ice heat storage device according to the present invention.

FIG. 15 is a schematic longitudinal sectional view showing a ninth embodiment of the ice heat storage device according to the present invention.

16A and 16B are diagrams showing the vicinity of the flapper switch of the ice heat storage device shown in FIG. 15, wherein FIG. 16A shows a state before the flapper switch is operated, and FIG.

FIG. 17 is a schematic longitudinal sectional view showing a tenth embodiment of the ice heat storage device according to the present invention.

FIG. 18 is an enlarged view of an ice amount detection unit of the ice heat storage device shown in FIG. 17 and shows a state at the time of the detection.

FIG. 19 is a perspective view showing an ice heat storage tank in an eleventh embodiment of the ice heat storage device according to the present invention.

FIG. 20 is an enlarged longitudinal sectional view showing the vicinity of the ejection part of the ice heat storage tank shown in FIG. 19;

FIG. 21 is a view as viewed in the direction of the arrow X in FIG. 20;

FIG. 22 is a block diagram showing an embodiment of an ice storage air conditioning system according to the present invention (a twelfth embodiment of the present invention).

23 is a block diagram schematically showing a control system of the ice storage air conditioning system shown in FIG.

FIG. 24 is a block diagram showing a first example of a conventional ice heat storage device.

FIG. 25 is a block diagram showing a second example of a conventional ice heat storage device.

FIG. 26 is a block diagram showing a third example of a conventional ice heat storage device.

FIG. 27 is a block diagram showing a fourth example of a conventional ice heat storage device.

FIG. 28 is a block diagram showing a fifth example of a conventional ice heat storage device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Outdoor heat exchanger 3 Expansion valve 3a Electric control valve 4 Subcooler 5 Refrigerant circuit 6p Pressure detector 6t Refrigerant temperature detector 6t 'Liquid-side refrigerant temperature detector 7 Bypass circuit 7v Bypass circuit opening / closing valve 8 Four-way Valve 10, 10 'Ice thermal storage tank 10a One side of ice thermal storage tank 10b Other side of ice thermal storage tank 12, 12' Subcooling release plate 14 Spouting section 16 Coolant pipe 18 Barrier member 12s, 16s, 18s Ice amount detecting means 20 Coolant pump 21 Coolant circuit 22 Coolant temperature detector 24 Flapper switch (ice amount detecting means) 26 Ice amount detecting unit (ice amount detecting means) C, C1, C2, C3 Control means A Indoor unit B Outdoor unit U Ice Heat storage unit L, L 'Coolant I Ice V1 Two-way valve (valve mechanism)

Claims (20)

[Claims] 1. A refrigeration cycle comprising at least a compressor, an outdoor heat exchanger, an expansion mechanism and a subcooler connected to each other, and ice and coolant generated from a coolant supercooled by the subcooler. An ice heat storage tank for accumulating heat, a coolant temperature detector for detecting a degree of subcooling of the coolant at an outlet side of the subcooler, and detecting an evaporation pressure of the refrigerant at an outlet side of the subcooler. And a control means for controlling the number of revolutions of the compressor, the control means comprising: a supercooling degree of the coolant detected by the coolant temperature detector; and When the saturation temperature reaches a lower limit preset according to the degree of supercooling of the cooling liquid, based on the saturation temperature of the refrigerant corresponding to the evaporation pressure detected by the compressor, the compressor rotates. Specially reduce the number temporarily. Ice thermal storage device to. 2. A refrigeration cycle comprising at least a compressor, an outdoor heat exchanger, an electric control valve as an expansion mechanism, and a subcooler connected to each other; An ice heat storage tank for accumulating ice and coolant, a coolant temperature detector for detecting a degree of subcooling of the coolant at an outlet side of the supercooler, and a refrigerant at an outlet side of the supercooler. A pressure detector for detecting an evaporating pressure of the coolant, and control means for controlling an opening degree of the electric control valve, wherein the control means supercools the coolant detected by the coolant temperature detector. Degree, based on the saturation temperature of the refrigerant corresponding to the evaporation pressure detected by the pressure detector, this saturation temperature,
An ice heat storage device characterized by temporarily increasing an opening degree of the electric control valve when a lower limit value set in advance according to a degree of supercooling of the coolant is reached. 3. The ice heat storage device according to claim 1, wherein a lower limit value of a saturation temperature of the refrigerant is set to increase as a degree of supercooling of the coolant decreases. 4. A refrigerant temperature detector for detecting a refrigerant temperature at an outlet side of the supercooler, wherein the control means detects a saturation temperature of the refrigerant and a detection of the saturation temperature and the refrigerant temperature detector. When the degree of superheat reaches a predetermined upper limit and the saturation temperature of the refrigerant reaches the lower limit,
3. The ice heat storage device according to claim 1, wherein the rotation speed of the compressor is temporarily reduced, or an opening of the electric control valve is temporarily increased. 4. 5. The method according to claim 1, wherein the control unit temporarily reduces the rotation speed of the compressor when the time rate of change of the degree of superheat reaches a predetermined upper limit, or sets the degree of opening of the electric control valve. The ice heat storage device according to claim 4, wherein is temporarily increased. 6. The system according to claim 1, wherein the lower limit of the saturation temperature of the refrigerant is changed when the frequency of freezing in the subcooler reaches a predetermined upper limit.
Or the ice heat storage device according to 2. 7. A refrigeration cycle comprising a bypass circuit bypassing the subcooler and having an on-off valve, wherein the control means is configured to switch the bypass circuit when the saturation temperature of the refrigerant reaches the lower limit. The ice heat storage device according to any one of claims 1 to 6, wherein the on-off valve is temporarily opened. 8. A refrigeration cycle comprising at least a compressor, a four-way valve, an outdoor heat exchanger, an expansion mechanism and a subcooler connected to each other, and ice generated from a coolant supercooled by the subcooler. An ice thermal storage tank for storing cooling liquid;
An ice heat storage unit having a coolant circuit connecting the ice heat storage tank and the subcooler; a coolant pump for circulating the coolant through the coolant circuit; and the refrigeration by the four-way valve. Control means for switching between a cooling or ice making operation and a heating operation of a cycle and for controlling the operation of the coolant pump, wherein the control means temporarily stops the freezing in the subcooler when it occurs. An ice heat storage device characterized by performing a freeze-release operation for switching the four-way valve so that the refrigeration cycle performs a heating operation and stopping the operation of the coolant pump. 9. The ice heat storage device according to claim 8, wherein said control means operates said coolant pump temporarily when performing said freeze release operation. 10. When the freezing occurs again in the subcooler within a predetermined time after the execution of the freeze releasing operation, the control means performs the freeze releasing operation again, and 9. The ice heat storage device according to claim 8, wherein the ice making operation for generating ice is terminated. 11. An ice amount detecting means for detecting that the volume of ice accumulated in the ice heat storage tank has reached a predetermined allowable amount, wherein the ice amount detecting means has an ice volume of The ice according to any one of claims 1 to 10, wherein the ice making operation for generating ice from the coolant is terminated when it is detected that the predetermined amount has been reached. Heat storage device. 12. The ice amount detecting means is provided on a side surface of the ice heat storage tank above a liquid level of the cooling liquid, and is an introduction pipe for introducing a cooling liquid eluted from ice in the ice heat storage tank. The ice heat storage device according to claim 11, further comprising: a temperature sensor for detecting a coolant introduced into the introduction pipe. 13. An ice heat storage tank for accumulating ice and cooling liquid generated from a supercooled cooling liquid, provided on one side of the ice heat storage tank, and cooling the cooling liquid to cool the cooling liquid. A supercooler for setting a cooling state; a jetting unit provided on one side of the ice heat storage tank for jetting the supercooled cooling liquid; and a jetting unit provided on the other side of the ice heat storage tank. A supercooling release plate for releasing the supercooled state by colliding the coolant jetted from the jetting portion to release the supercooled state, and a subcooling release plate having an intake port; An ice heat storage device, comprising: a cooling liquid pipe for guiding the introduced cooling liquid to one side of the ice heat storage tank; and the cooling liquid pipe is provided in the ice heat storage tank. 14. An ice amount detecting means for detecting that the volume of the ice reaches a predetermined allowable amount due to contact of the ice accumulated in the ice heat storage tank is provided in the coolant pipe. 14. An ice making operation for generating ice from the cooling liquid when the ice amount detecting means detects that the ice reaches a predetermined allowable amount, wherein the ice making operation is terminated. The ice heat storage device as described in the above. 15. The ice heat storage device according to claim 14, wherein said ice amount detecting means is provided on said subcooling release plate. 16. The apparatus according to claim 16, wherein the ejection section is provided so as to protrude into the ice heat storage tank, and a barrier member for preventing rise of ice in the ice heat storage tank is provided below the ejection section. 14. The ice heat storage device according to claim 13, wherein: 17. The ice heat storage device according to claim 16, wherein the barrier member has a wedge-shaped cross-sectional shape that expands upward. 18. An ice amount detecting means for detecting that the volume of the ice reaches a predetermined allowable amount by contact of the ice accumulated in the ice heat storage tank is provided at a bottom portion of the barrier member. When the ice amount detecting means detects that the ice reaches a predetermined allowable amount, the ice making operation for generating ice from the cooling liquid is terminated. The ice heat storage device according to claim 16 or 17, wherein: 19. The ice heat storage device according to claim 13, wherein a filter for preventing entry of ice is provided at a water intake of the subcooling release plate. 20. An ice storage air conditioning system comprising an outdoor unit, an ice heat storage unit, and an indoor unit, wherein at least a compressor, an outdoor heat exchanger, an expansion mechanism, an indoor heat exchanger, and a subcooler are connected. The outdoor unit has at least the outdoor heat exchanger, and the ice heat storage unit is generated from at least the subcooler and a cooling liquid supercooled by the subcooler. An ice heat storage tank for accumulating ice and cooling liquid, wherein the indoor unit has at least the indoor heat exchanger, and a valve mechanism is provided in the refrigerant circuit, and by switching the valve mechanism, An ice storage air conditioning system, wherein the air conditioning operation is performed only by the outdoor unit and the indoor unit.