JPH085110A - Heat exchanger for heat accumulation - Google Patents

Abstract

PURPOSE:To obtain a heat exchanger for heat accumulation which dispenses with control of the amount of cold storage and shows a high fill rate of ice, by preventing unfrozen water from being sealed up in ice at the time of an additional cold storage operation and by minimizing an energy loss being incidental to elimination of the sealed state of the unfrozen water. CONSTITUTION:In this heat exchanger for heat accumulation, sealed water 3 formed of ice melting on the surface of a heat transfer tube 1 and sealed up in the surrounding ice 17 after a cold release operation, for instance, is frozen to be the ice 17 at the time of another cold storage operation, and a pressure rise is caused by the volume expansion of the ice 17 at this time. Since a thick-wall heat insulating body 16 being a nonconductor of heat is so provided as to project more in the direction of a tube diameter than the thickness of the ice 17 at the time when the maximum amount of cold storage is reached, in this case, the ice 17 is absent at the position of disposition of the thick-wall heat insulating body 16 and the ice 17 is divided into upper and lower portions at this position. Accordingly, the sealed water 3 of which the pressure rises flows out into water 3a outside the ice along the surface of the thick-wall heat insulating body 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a static heat exchanger for heat storage applied to, for example, a heat storage type air conditioner, and more particularly to a structure of a heat transfer tube portion of a heat storage tank for ice making and cold heat control. It is a thing.

[0002]

2. Description of the Related Art FIG.
FIG. 1 is a system diagram of a heat storage material circulation type heat storage type air conditioner that has a heat storage tank that stores a heat storage material capable of storing heat and is disclosed in Japanese Patent Publication No. In the figure, reference numeral 1 denotes a heat storage heat transfer tube provided in a heat exchange part of the heat storage heat exchange device (hereinafter referred to as a heat transfer tube).
Is. The heat transfer tube 1 is immersed in water 3a as a heat storage material filled in the heat storage tank 2, and constitutes a cool storage circuit 5 (for example, a refrigerant circulation path) together with the cooling device 4. Also, together with the use side heat exchanger 6 and the circulation pump 7,
A cooling circuit 8 is configured to circulate the cooled water 3a to cool the user side.

Further, the heat storage tank 2 has an upper open portion 9, and the liquid level 10 of the water 3a can be detected by a liquid level detecting device 11. When operating such a heat storage type air conditioner, while circulating the water 3a which is an unfrozen part,
During the cold storage (ice making) operation, the rise of the liquid level 10 due to the volume expansion accompanying the phase change from the water 3a to the ice is detected by the liquid level detection device 1
1 to prevent the collapse of the heat transfer tube 1 (compression due to external pressure) due to volume expansion of ice by stopping the cold storage operation within the range where the cold storage operation limit (predetermined ice filling rate) is not reached. It is supposed to do.

The ice making method of this heat storage type air conditioner relies on the static method of adhering ice to the heat transfer tube 1.
In some cases, the water 3a in the unfrozen part in the heat storage tank 2 may remain in a blocked state between the freezing part and the heat transfer tube 1, and when the unfrozen part is frozen due to the restart of the subsequent cold storage operation, Heat transfer tube 1 due to volume expansion of ice frozen in the part
There is a risk of crushing. Therefore, according to this heat storage type air conditioner, the additional cold storage operation is stopped when the predetermined amount of ice making is reached, which is effective as a countermeasure against the heat transfer tube collapse, but the liquid level detection device 11
It is difficult to say that this is a very effective method because it has problems such as an increase in cost due to the installation of a heat storage tank and a shortage of cold storage due to the inability to store cold by fully utilizing the volume of the heat storage tank 2.

FIG. 11 is a refrigerant circuit diagram of a direct expansion heat storage type air conditioner using a refrigerant, which is disclosed in Japanese Unexamined Patent Publication No. 5-264077. The compressor 12, the non-use side (outdoor side) ) A cold storage operation circuit when the refrigerant is circulated through the components of the heat storage tank 2 including the heat exchanger 13, the expansion device 14, and the heat transfer tube 1 in the route indicated by the solid line arrow in the figure, and the refrigerant pump 7.
a, the heat storage tank 2 including the heat transfer tube 1, the expansion device 14a, and the constituent devices of the heat exchanger 6 on the use side, the cooling (melting ice) operation circuit when the refrigerant is circulated in the route indicated by the broken line arrow in the figure. And, respectively. In the case of each of the circuits described above, ice making and melting of the water 3a by heat exchange through the heat transfer tube 1 are always performed from the vicinity of the heat transfer tube 1 toward the distance. In addition, since the ice melt during the cooling operation changes phase from the ice near the heat transfer tube 1 to water in sequence, cooling is performed for a relatively short time (melting ice) that is less than the specified time.
When the cold storage operation is restarted after the operation, the water 3a is immediately near the heat transfer tube 1.
Is likely to become blocked. In such a heat storage type air conditioner, when the cold storage operation is restarted after the cold discharge operation is performed and water is likely to be blocked, the cold storage operation is performed so as not to perform the additional cold storage operation. It is necessary to control the amount of cold storage such as setting a control area related to prohibition. For this reason, there is always a control area in which the cold storage operation for storing the required amount of ice is impossible, and there is a case where the cold storage amount becomes insufficient during the cold discharge operation.

FIG. 12 shows a Japanese Patent Application No. 5-32041.
FIG. 12 is a view showing a configuration mode of a heat transfer tube similar to that shown in the refrigerant circuit of FIG. In the figure, the heat transfer tube 1 formed in a coil shape is configured to be immersed in the water 3a in the heat storage tank in a state where the upper and lower ends are supported by the hanger 15. According to this configuration, during ice making,
Although ice adheres to and grows around the heat transfer tubes 1, when excessive cold storage operation is performed, the water 3a between the adjacent heat transfer tubes 1 is partially blocked as in the case of the other conventional example. In order to obtain it, it was essential to control the amount of cold storage as shown above.

[0007]

Since the heat storage heat exchange device in the conventional heat storage type air conditioner is constructed as described above, the cold storage operation is restarted after performing the cooling operation for a relatively short time. In doing so, it was necessary to control the amount of cold storage such as the operation control that set the ice making amount limit and the control area related to the additional cold storage operation prohibition. In addition, the ice filling rate of the heat storage tank was relatively low, and it was not possible to keep it above a certain level. Therefore, problems such as insufficient amount of cold storage may occur due to the inability to perform cold storage operation making full use of the total capacity of the heat storage tank. Also,
There is also a demerit that the cost required to install the detection device for detecting the liquid level and the like is unavoidable.

The present invention has been made in order to solve the above-mentioned problems, and does not block the unfrozen water inside the ice when the cold storage operation is restarted. It is an object of the present invention to provide a heat storage device for heat storage that does not require control of the amount of stored cold and has a high ice filling rate by minimizing the energy loss that accompanies the elimination.

[0009]

A heat storage heat exchange device according to the present invention is a heat storage heat exchange device in which heat transfer tubes for exchanging heat with water are arranged in a heat storage tank containing water. , A heat-defective conductor having a smaller thermal conductivity than that of the heat-transfer pipe is arranged at least in close proximity to a part of the heat-transfer pipe, and ice to be frozen at the position where the heat-defective conductor is arranged is thinner or lost than other parts of the heat-transfer pipe. It was done like this.

The poor heat conductor is a thick-walled heat insulator whose length in the radial direction from the surface of the heat transfer tube is equal to or larger than the ice thickness when the maximum amount of cold storage is reached.

Further, the heat-defective conductor is a thin-walled heat insulator whose length in the radial direction from the surface of the heat transfer pipe is less than the ice thickness when the maximum amount of cold storage is reached.

On the other hand, in a heat storage heat exchange device in which heat transfer tubes for exchanging heat with water are arranged in a heat storage tank containing water, a heating element is disposed at least near the heat transfer tube, The heat from the heating element melts the frozen ice around the heating element to form a water flow path that connects the surface of the heat transfer tube and the outside of the ice.

Further, the heating element is formed such that its length from the surface of the heat transfer tube in the tube radial direction is equal to or more than the ice thickness when the maximum amount of cold storage is reached and the support structure holds the heat transfer tube. is there.

Further, the heating element is composed of a heating wire.

Further, a heating time storage means for storing a preset heating time of the heating element and a first control means for heating the heating element for a predetermined heating time stored from the start of the cold storage operation are provided. It is a thing.

Further, during the cold storage heat utilization operation, a time counting means for measuring and integrating the cold storage heat utilization operation time, and a second control means for causing the heating element to generate heat for a time based on the accumulated cold storage heat utilization operation time during the cold storage operation. And are provided.

In each of the above constructions, the heat transfer tubes are arranged with the longitudinal direction thereof oriented substantially vertically.

[0018]

In the heat storage device for heat storage according to the present invention,
For example, water that is thawed on the surface of the heat transfer tube after the cold heat utilization operation and is clogged in the surrounding ice is frozen and turned into ice during the cold energy storage operation again, but the pressure increases due to the volume expansion of this ice. In this case, due to the presence of the heat-defective conductor, the ice is not frozen at the position where the heat-defective conductor is arranged, or even if the ice is frozen, the ice is formed to have a smaller thickness than other portions. Therefore, the water whose pressure has increased breaks down the thin ice portion and flows out of the ice, or flows out of the ice along the surface of the heat-defective conductor in the portion where there is no ice.

Further, the thick heat insulator as the heat-defective conductor is
It protrudes in the pipe diameter direction more than the ice when the maximum amount of cold storage is reached.
Therefore, there is no ice at the position where the thick heat insulator is arranged, and the thick heat insulator is divided. Therefore, the water that is blocked in the ice and has increased in pressure flows out of the ice along the surface of the thick heat insulator.

Further, the thin-walled heat insulator as a heat-defective conductor is
It is buried in ice when the maximum amount of cold storage is reached. However, the ice frozen at the position where the thin heat insulator is arranged is formed to have a thinner thickness than that of the other portions. Therefore, the water, which is blocked in the ice and whose pressure is increased, breaks the ice in the thin portion and flows out of the ice from the broken portion.

On the other hand, the heating element arranged at least near the heat transfer tube melts the ice around the heating element by heat generation.
As a result, a water flow path that connects the surface of the heat transfer tube and the outside of the ice is formed. Therefore, even if the pressure of water rises in the ice, the water flows out of the ice through the water circulation path.

If the heating element projects more in the tube radial direction than the ice when the maximum amount of cold storage is reached, no ice is formed at the location where the heating element is arranged. In addition, the heating element melts the surrounding ice. Therefore, the water that has been blocked in the ice and the pressure of which has risen easily flows out of the ice along the heating element. Further, since the heat generating body sandwiches the heat transfer tube, it becomes a structural member for supporting the heat transfer tube.

Further, the heating wire as a heating element melts the surrounding ice by energizing. Therefore, the water that is blocked in the ice and the pressure of which rises can easily flow out of the ice along the heating wire.

Further, the first control means causes the heating element to generate heat for a predetermined heat generation time stored in advance in the heat generation time storage means from the start of the cold storage operation. Therefore, even though the heat transfer tubes are prevented from being crushed, the ice cubes obtained during the normal cold storage operation are not unnecessarily thawed.

Further, the time measuring means measures and integrates the cold storage heat utilization operation time during the cold storage heat utilization operation. Then, the second control means causes the heating element to generate heat during the cold storage operation for the cold storage heat utilization operation time accumulated by the timing means. On the other hand, the second control means, during the normal cold-cooling operation that can completely thaw the ice, during the cold heat utilization operation or other operation,
Do not execute the operation to prevent the heat transfer tubes from collapsing.

The heat transfer tubes arranged with their longitudinal directions oriented substantially vertically cause natural convection of the water around the heat transfer tubes during the thawing of the ice due to a change in specific gravity thereof to form a water flow path with the outside of the ice. Make it easier. Therefore, it is difficult to block water in ice.

[0027]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Example 1. FIG. 1 is a partial perspective view of a heat storage heat exchange device showing one embodiment of claims 1 and 2. In the figure,
Reference numeral 1 is a heat transfer tube of a heat storage heat exchange device immersed in a heat storage material (here, water) in a heat storage tank, and 16 is a disk-shaped thick heat insulator attached to the heat transfer tube 1 at predetermined vertical intervals. In addition, FIG. 2 shows a state in which ice 17 adheres to and grows around the heat transfer tube 1 in FIG. 1, and the ice 17 around the heat transfer tube 1 is slightly melted by a relatively short-time cooling (melting ice) operation. Is a partial cross section. In the figure, 17 is ice, 3 is closed water generated by melting ice around the heat transfer tube 1 and closed in the ice 17,
3a shows water in the heat storage tank which is not iced.

At the portion where the thick-walled heat insulator 16 is attached, the ice 17 is divided, and the thick-walled heat insulator 16 where ice does not grow in this portion is thickened in the radial direction of the heat transfer tube 1. If it is formed to have a thickness equal to or more than the ice thickness when the maximum amount of cold storage is reached, even if the ice 17 grows considerably, the thick-walled heat insulator 16
The state of division by does not change. Therefore, when an additional cold storage operation is performed from the state in which the closed water 3 exists, the closed water 3 expands in volume when it changes into ice. At this time, since the ice 17 is divided by the thick-walled heat insulator 16, the unfrozen closed water 3 which is compressed due to the new volume expansion of the ice fills the gap between the ice 17 and the thick-walled heat insulator 16. It passes through and is discharged to the part of water 3a in the heat storage tank. Therefore, unlike the conventional device in which the thick heat insulator 16 is not provided, the heat transfer tube is not crushed due to the stress concentration applied to the heat transfer tube 1 through the closed water 3 due to the volume expansion of ice. If the maximum ice thickness is known in advance, it is possible to reliably prevent the heat transfer tube from being crushed for any ice thickness.

Since the location and distribution of the closed water 3 cannot be limited, it is desirable that the thick heat insulator 16 be attached to the heat transfer tube 1 at intervals of several times the maximum growth diameter of the ice 17. The thick heat insulator 16 may be a heat-defective conductor made of a material having a smaller thermal conductivity than the heat transfer tube 1 (made of copper, for example). In addition, the thick-walled heat insulator 16 is used for the closed water 3
A ring-shaped member having an inner diameter smaller than the outer diameter (inner diameter of the ice 17) of the closed water 3 portion affected by the volume expansion of the heat transfer tube 1, or the heat transfer tube 1. The heat transfer tube 1 may be formed in such a manner that it has an inner diameter substantially equal to the outer diameter of the heat transfer tube 1. The shape is not limited to the disc shape described above. However, the maximum outer diameter of the thick-walled heat insulator 16 is set within the range in which the ice filling rate is set to 100% because it is not considered in actual operation control of the heat storage air conditioner that the ice filling rate is set to 100%. It is sufficient to determine the maximum ice thickness outer diameter at that time. On the other hand, even if the maximum ice filling rate is set higher than in the conventional case, the maximum outer diameter of the thick-walled heat insulator 16 may be set to the maximum ice thickness outer diameter at that time, so that the volume of the heat storage tank can be fully utilized. It should be noted that, as in this embodiment, the thick-walled heat insulator does not have to be provided independently for each heat transfer tube 1, but may be provided between adjacent heat transfer tubes as long as it is within the above ice filling rate. It may be a common rectangular plate to be passed.

Example 2. FIG. 3 is a partial perspective view of the heat exchange device for heat storage showing an embodiment according to claims 1 and 3. In the figure, 16a is a coating (an example of a thin heat insulator) attached to the outer peripheral surface of the heat transfer tube 1 at a predetermined upper and lower intervals. The coating 16a is formed so that the thickness from the surface of the heat transfer tube 1 in the tube radial direction is less than the ice thickness when the maximum amount of cold storage is reached, and the material thereof may be smaller than the thermal conductivity of the heat transfer tube 1. However, it is not particularly limited. For example, it may be wound up and down at a predetermined interval using a heat insulating tape or the like.

FIG. 4 is a partial cross-sectional view showing a state where ice is frozen around the heat transfer tube in FIG. 3 due to the cold storage operation, and shows a state in which ice 17 is attached around the heat transfer tube 1. In the figure, the growth state of the ice 17 due to the attachment of the coating film 16a is different in the cross-sectional diameter of the ice 17 due to the difference in heat conduction between the attached portion and the non-attached portion. For this reason,
When the water clogging condition around the heat transfer tube 1 as shown in Example 1 occurs, if the growth of the ice 17 is limited to a small range, the stress due to the volume expansion at the time of refreezing has a small diameter of the ice 17. The portion (thin ice portion) is overcome to break the ice, and the compressed water is caused to flow into the water 3a outside the ice through the water circulation path by the breaking ice. Therefore, according to the present embodiment, the heat transfer tube can be prevented from being crushed with a structure that is relatively inexpensive and has a small amount of mounting work. Incidentally, the film 16
Although a is effective when used in a straight pipe portion that is easily affected by water blockage, it may be provided in other portions, for example, in portions where the pipe wall thickness is small.

Example 3. FIG. 5 shows claims 4 and 5.
It is a partial perspective view of the heat exchange device for heat storage showing one embodiment. In the figure, reference numeral 18 denotes a heating element attached so as to sandwich the heat transfer tube 1 at a plurality of positions from both sides, and is configured by including a heating wire or the like and utilizes heat generated by energization. The heating element 18 is formed to have a thickness in the radial direction of the pipe that is equal to or larger than the ice thickness when the maximum amount of cold storage is reached, and has a support structure that holds the heat transfer pipe 1 therebetween. According to the heat exchange device for heat storage of the present embodiment, it is possible to have both the effect of forming an ice-free portion similar to that of the above-described Embodiment 1 and the effect of melting the heat of the heat generating element 18, thus preventing the heat transfer tube from collapsing. High reliability,
In addition, it can be used as a structural member for supporting the heat transfer tube, which is extremely cost-effective.

Example 4. FIG. 6 shows claims 4 and 6.
It is a partial perspective view of the heat exchange device for heat storage showing one embodiment. In the figure, reference numeral 18a is a heating wire which is installed so as to be in contact with or close to the heat transfer tube 1 and which is a heating wire. The heating wire 18a generates heat when energized. At this time, the ice near the heating wire 18a is partially melted, and the closed water in the immediate vicinity of the heat transfer tube 1 and the unfrozen water 3a can be communicated with each other.
Since the water flow path of the blocked water as described above can be formed, the heat transfer tube 1 can be prevented from being crushed. According to the heat storage device for heat storage of the present embodiment, the effect as a structural support, unlike the device in the third embodiment, is not exhibited, but it is advantageous in that the device can be easily and inexpensively constructed. Have.

Example 5. FIG. 7 shows claims 4 and 7.
2 is a graph showing a method of controlling the energization time (heating time) to the heating element (or the heating wire), and the cold storage operation is restarted after the cooling (melting ice) operation or the cooling operation is stopped according to the passage of time on the horizontal axis. At this time, it is specified that the heating element (for example, the heating element 18 of the third embodiment or the heating wire 18a of the fourth embodiment) is energized for a predetermined heating time at the start of the cold storage operation. Here, the predetermined heat generation time is the time during which the frozen portion around the heat generating element is partially thawed after the heat generating element is energized,
Alternatively, it is a time period in which the blocked water around the heat transfer tube can be released into the unfrozen water in the heat storage tank by the volume expansion during the additional cold storage operation. In the heat storage device for heat storage according to this embodiment, as shown in FIG. 6, a preset heating element (here,
Memory 19 for storing the predetermined heat generation time of heat generation line 18a)
(Example of heat generation time storage means), and a control device 20 (an example of first control means) that energizes the heating element to generate heat for a predetermined heating time stored from the start of the cold storage operation. . These memory 19 and control device 20
Therefore, by setting the predetermined heat generation time only immediately after the cold storage operation is started, it does not unnecessarily unravel the ice cubes obtained in the normal cold storage operation, and the electric power required for energization is also saved to save energy. Loss can be minimized.

Example 6. FIG. 8 is a graph that defines the energization time to the heating element according to the cumulative time of the cooling (cooling / melting) operation with respect to claims 4 and 8, and is below a certain constant cooling operation cumulative time. Only, the energization time is set by I or II in the graph. In the heat exchange device for heat storage according to this embodiment, as shown in FIG. 6, a timer 21 (timer means for measuring, accumulating and holding the operation time for use of cold storage heat during cold storage use operation (cooling operation etc.) Control unit 20 (second control means) that energizes the heating element (here, the heating wire 18a) to generate heat for an energization time based on the cold storage heat utilization operation time accumulated by the timer 21 during the cold storage operation. Is provided). The control device 20 and the timer 21 can perform control to prevent the heat transfer tube from being crushed only for a short cooling operation time so that water is easily blocked around the heat transfer tube 1, and the entire amount of ice is thawed. By limiting the energization only during additional cold storage operation, excluding the normal cold storage operation and cold storage operation, it is possible to cut energy loss such as melting ice operation and energization that are unnecessary during normal cold storage operation. You can do it.

Example 7. FIG. 9 relates to claim 9, and in order to further enhance the heat transfer tube collapse prevention effect shown in claim 1 and claim 4, in addition to the above configuration, heat transfer tubes are provided in a vertical arrangement in a heat storage tank. It is a state explanatory view showing a state of melting ice in a partial section. As shown in the figure, the heat transfer tubes 1 are arranged with their longitudinal directions oriented vertically. As a result, the natural convection water 3b is generated due to the change in the specific gravity of the water around the heat transfer tube 1 during ice melting, and the heat transfer effect is enhanced. Therefore, a water flow path is formed between the outside of the ice and the ice, so that the water is not blocked inside the ice. Furthermore, by combining the configuration of the present embodiment with the above-described configuration for eliminating the water blocking state, the heat transfer tube collapse prevention effect can be promoted and made more reliable.

[0037]

As described above, according to the present invention,
For example, even if the water that melts on the surface of the heat transfer tube after the cold heat utilization operation and is clogged in the surrounding ice causes volume expansion when freezing during the cold energy storage operation again and the pressure rises, the placement of the heat-defective conductor Since the frozen ice is thin or absent at the position, the water with increased pressure breaks through the thin ice portion and flows out of the ice, or the ice along the surface of the heat-defective conductor in the ice-free portion Spill to. Therefore, stress concentration on the heat transfer tube due to volume expansion of water blocked in ice does not occur,
Does not cause heat transfer tube crush.

Further, in the structure according to the invention of claim 1, the heat-insulating conductor is formed such that the length in the radial direction from the surface of the heat transfer tube is equal to or larger than the ice thickness when the maximum amount of cold storage is reached. In such a case, since there is no ice at the position where the heat-defective conductor is disposed, water that has been blocked in the ice and has increased in pressure can flow out of the ice along the surface of the heat-defective conductor. Therefore, it is possible to prevent the heat transfer tube from collapsing. Moreover, this thick-walled heat insulator is relatively inexpensive and requires a small amount of mounting work.

Further, in the structure according to the first aspect of the invention, the heat-defective conductor is formed to have a predetermined length such that the length from the surface of the heat transfer tube in the pipe radial direction is less than the ice thickness when the maximum amount of cold storage is reached. When a heat insulator is used, the ice frozen at the location where the heat-defective conductor is placed has a thin thickness, so water that has been blocked inside the ice and has increased in pressure breaks the thin portion of the ice, Runs out of ice. Therefore, it is possible to prevent the heat transfer tube from collapsing. In addition, this thin heat insulator is also relatively inexpensive and requires a small amount of mounting work.

On the other hand, the heat from the heating element arranged at least near the heat transfer tube melts the ice frozen around the heating element to connect the surface of the heat transfer tube to the outside of the ice. Since the water flow path is formed, the water that has been blocked in the ice and has increased in pressure flows out of the ice through the water flow path.
Therefore, it is possible to prevent the heat transfer tube from being crushed, and the heating element can be provided relatively easily.

Further, in the structure according to the invention of claim 4, when the heating element is formed such that the length from the surface of the heat transfer tube in the pipe radial direction is equal to or more than the ice thickness when the maximum amount of cold storage is reached, the heating element is arranged. There is no ice at the position, and the heat from the heating element also melts the surrounding ice. Therefore, the water, which has been blocked in the ice and whose pressure has risen, can very easily flow out of the ice along the heating element. As a result, it is possible to reliably prevent the heat transfer tube from collapsing. In addition, since the heating element is configured as a support structure for sandwiching the heat transfer tube, it can also be used as a structural member for supporting the heat transfer tube, so that a cost-effective one can be realized.

Further, in the structure according to the invention of claim 4, when the heating element is constituted by the heating wire, the surrounding ice is thawed by the heat from the heating wire. Therefore, the water that is blocked in the ice and the pressure of which rises can easily flow out of the ice along the heating wire. As a result, it is possible to prevent the heat transfer tube from collapsing. That is, according to this structure, the effect as a supporting structural member is not exhibited, but on the other hand, there is an advantage that the heat storage device for heat storage can be manufactured easily and inexpensively.

Further, since the first control means causes the heating element to generate heat for a predetermined heat generation time stored in advance in the heat generation time storage means from the start of the cold storage operation, it can be said that the heat transfer tube is prevented from collapsing. , Do not thaw the ice cubes you got during cold storage operation more than necessary. Therefore, energy loss can be minimized.

Further, since the second control means is configured to heat the heating element during the cold storage operation for the cold storage heat utilization operation time accumulated by the time counting means, the water obtained by thawing on the surface of the heat transfer tube is The operation for preventing collapse of the heat transfer tubes can be executed only during the time when the relatively low heat storage utilization operation is executed so that the ice is easily blocked in the surrounding ice. on the other hand,
The operation for preventing the heat transfer tubes from collapsing is not executed during the cold storage heat utilization operation such as the normal cooling operation in which the entire amount of ice can be thawed and other operations. Therefore, it is possible to reduce energy loss such as unnecessarily thawed ice during the normal cold storage operation and the amount of power consumed by the heating element.

Since the heat transfer tubes are arranged so that their longitudinal directions are substantially vertical in the above-described structure, natural convection is likely to occur due to a change in the specific gravity of water around the heat transfer tubes at the time of thawing. And the water is not blocked in the ice. Therefore, the effect of preventing the heat transfer tube from being crushed can be enhanced and further ensured.

[Brief description of drawings]

FIG. 1 is a partial perspective view showing a heat exchange device for heat storage according to an embodiment of the invention of claims 1 and 2. FIG.

FIG. 2 is a state explanatory view showing, in a partial cross section, a state in which the periphery of the heat transfer tube of the heat storage device for heat storage of FIG. 1 is frozen due to restart of the cold storage operation.

FIG. 3 is a partial perspective view showing a heat storage heat exchange device according to an embodiment of the present invention.

FIG. 4 is a state explanatory view showing, in a partial cross-section, a state in which the periphery of the heat transfer tube of the heat storage device for heat storage of FIG. 3 is frozen due to restart of the cold storage operation.

FIG. 5 is a partial perspective view showing a heat exchange device for heat storage according to an embodiment of the inventions of claims 4 and 5.

FIG. 6 is a partial side view showing a heat storage device for heat storage according to one embodiment of the inventions of claims 4 and 6.

FIG. 7 is a graph showing a method of controlling the energization time to the heating element in the heat storage heat exchange device according to one embodiment of the inventions of claims 4 and 7.

FIG. 8 is a graph that defines an energization time to a heating element according to a cooling operation integrated time in the heat storage heat exchange device according to one embodiment of the inventions of claims 4 and 8.

FIG. 9 is a partial cross-sectional view illustrating a state in which the periphery of the heat transfer tubes in the heat storage device for heat storage according to the ninth embodiment of the present invention is frozen due to restart of the cold storage operation.

FIG. 10 is a system diagram of a conventional heat storage type air conditioner as an example of the background of the present invention.

FIG. 11 is a refrigerant circuit diagram of a conventional heat storage type air conditioner as another example of the background of the present invention.

FIG. 12 is a partial perspective view showing a heat transfer tube configuration aspect of a conventional heat storage type air conditioner, which is still another example of the background of the present invention.

[Explanation of Codes] 1 heat transfer tube, 2 heat storage tank, 3 closed water, 3a water, 3b
Natural convection water, 16 thick wall insulation, 16a coating, 17
Ice, 18 heating element, 18a heating wire, 19 memory, 20
Controller, 21 timer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasufumi Hatamura 6-5-6 Tehira, Wakayama City Mitsubishi Electric Corporation Wakayama Factory

Claims (9)

[Claims] 1. A heat exchange device for heat storage, wherein a heat transfer tube for exchanging heat with water is arranged in a heat storage tank containing water, wherein a part of the heat transfer tube has a smaller heat than the heat transfer tube. Heat storage heat characterized by disposing heat-defective conductors having a conductivity at least close to each other so that ice that freezes at the position where the heat-defective conductors are arranged is thinner or eliminated than other portions of the heat transfer tube. Exchange device. 2. The heat-insulating conductor is a thick heat insulator whose length in the radial direction from the surface of the heat transfer tube is equal to or more than the ice thickness when the maximum amount of cold storage is reached. Heat storage device for heat storage. 3. The heat-insulating conductor is a thin-walled heat insulator having a length in the pipe radial direction from the surface of the heat transfer pipe that is less than the ice thickness when the maximum amount of cold storage is reached. The heat exchange device for heat storage according to 1. 4. A heat storage heat exchange device in which a heat transfer tube for exchanging heat with water is arranged in a heat storage tank containing water, wherein a heating element is disposed at least near the heat transfer tube. Then, the heat from the heating element is used to melt the ice frozen around the heating element to form a water flow path that connects the surface of the heat transfer tube and the outside of the ice. Characteristic heat exchange device for heat storage. 5. The heating element is formed such that the length in the tube radial direction from the surface of the heat transfer tube is equal to or more than the ice thickness when the maximum amount of cold storage is reached, and is configured to support the heat transfer tube. The heat exchange device for heat storage according to claim 4. 6. The heat exchange device for heat storage according to claim 4, wherein the heating element is composed of a heating wire. 7. A heat generation time storage means for storing a predetermined heat generation time of a preset heat generation element, and a first control means for causing the heat generation element to generate heat for the predetermined heat generation time stored from the start of the cold storage operation. 5. The method according to claim 4, further comprising:
A heat exchange device for heat storage according to claim 6. 8. A time control means for measuring and integrating a cold storage heat utilization operation time during the cold storage heat utilization operation, and a second control for causing the heating element to generate heat for a time based on the accumulated cold storage heat utilization operation time during the cold storage operation. The heat exchange device for heat storage according to any one of claims 4 to 6, further comprising means. 9. The heat exchange device for heat storage according to claim 1, wherein the heat transfer tubes are arranged with their longitudinal directions oriented substantially vertically.