JPH0424316Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) This invention relates to a heat storage device used in, for example, an air conditioner.

(Prior Art) Some air conditioners are equipped with a heat pump type refrigeration cycle and are capable of cooling and heating operations.

However, heating operation using a heat pump type refrigeration cycle has the disadvantage that the heating capacity is slow to rise at startup.

Therefore, some heat pump type refrigeration cycles are equipped with a heat storage device as shown in FIG. 4, and the heat stored in the heat storage device makes up for the lack of heating capacity at the time of startup.

In FIG. 4, reference numeral 1 denotes a heat storage device, in which a large number of needle-like fins 3 are provided radially protruding from the outer peripheral surface of a heat exchange pipe 2, and a heat storage material such as paraffin is placed around the heat exchange pipe 2 and the needle-like fins 3. 4 is filled. That is, the heat of the high-temperature refrigerant flowing through the heat exchange pipe 2 is transferred to the paraffin 4 via the needle-like fins 3, and the heat is stored by melting the paraffin 4. Further, the solidification of the paraffin 4 gives the stored heat to the refrigerant flowing through the heat exchange pipe 2.

In this case, a large number of needle-like fins are used as the fins, and each fin absorbs the volume change accompanying the phase change of the paraffin 4.
This is to prevent deformation or damage to the exterior. That is, the plate-shaped fins cannot absorb the volume change of the heat storage material, and are subjected to a large force, resulting in deformation and damage not only to the fins but also to their appearance.

However, the use of needle-like fins involves the following problems. That is, during heat storage, the paraffin 4 melts along the plane formed by the tip of each needle fin 3 and the plane formed by both ends of the row of fins, but the speed of heat transfer during the melting is different in each plane, A solid wall is formed on the outside of the plane formed by the ends of the fin rows. Then, the paraffin 4 expands between the solid phase wall and the end of the fin row, and a force in the direction of the arrow acts on the end of the fin row. In this way, as heat is accumulated repeatedly, the end portions of the fin rows take on a flattened shape as shown in FIG. This results in a decrease in the fin area and a significant decrease in heat exchange performance.

(Problems to be solved by the invention) This invention was made in view of the above-mentioned circumstances, and its purpose is to prevent deformation of the needle fins and to always maintain efficiency. The object of the present invention is to provide a highly reliable heat storage device that enables good heat exchange.

[Structure of the idea]

(Means for solving the problem) A heat exchange pipe having a large number of needle fins protruding radially from the outer circumferential surface is provided, and a heat storage material is filled around the heat exchange pipe and the needle fins. In the heat storage device, flanges with high rigidity and high heat conductivity from the pipe are provided on both sides of the heat exchange pipe.

(Function) The flange acts as a shield and no force is applied to the end of the fin row.

(Example) An example of this invention will be described below with reference to the drawings.

First, an air conditioner according to this invention is shown in FIG.

In FIG. 2, 11 is a compressor, and this compressor 11 includes a four-way valve 12, an indoor heat exchanger 13, and a heat storage device 2.
The heat exchange pipe 22a for heat absorption, the pressure reducing device such as the expansion valve 14, and the outdoor heat exchanger 15 are sequentially connected to form a heat pump type refrigeration cycle.
That is, during heating operation, the four-way valve 12 is switched to cause the refrigerant to flow in the direction of the solid arrow in the figure to form a heating cycle, with the indoor heat exchanger 13 acting as a condenser and the outdoor heat exchanger 15 acting as an evaporator. During cooling operation, the four-way valve 12 is returned to flow the refrigerant in the direction of the dashed arrow in the figure, causing the outdoor heat exchanger 15 to act as a condenser and the indoor heat exchanger 13 to act as an evaporator. Therefore, the electromagnetic on-off valve 16, the capillary tube 1
7. The series cycle of the heat exchange pipe 22b for heat radiation of the heat storage device 21 and the check valve 18 are connected in parallel. In addition, an indoor fan 19 is installed near the indoor heat exchanger 13,
An outdoor fan 20 is disposed near the outdoor heat exchanger 15.

The heat storage device 21 includes a heat exchange pipe 22a for heat absorption, a heat exchange pipe 22b for heat radiation, and an electric heater 26.
It has a heat storage material such as paraffin filled around it. However, the electric heater 26
is connected to the commercial AC power supply 32 through the contacts of the temperature switch 31 and the electromagnetic switch 44 in series.
The temperature switch 31 is turned on when the heat storage temperature of the heat storage device 21 falls below a predetermined value.

On the other hand, 40 is a control section that performs overall control of the air conditioner, and is composed of a microcomputer and its peripheral circuits. Therefore, the control unit 40 includes an operation operation unit 41, an indoor temperature sensor 42, an indoor heat exchanger temperature sensor 43, an electromagnetic switch 44, an electromagnetic switch valve 16,
A compressor 11, a four-way valve 12, etc. are connected.

Here, a specific example of the endothermic heat exchange pipe 22a in the heat storage device 21 and its surrounding area is shown in FIG.

As shown in FIG. 1, the heat exchange pipe 22 for heat absorption
A large number of needle-like fins 23 are provided radially protruding from the outer peripheral surface of the heat exchange pipe 22a, and flanges 25, 25 are provided on both sides of the heat exchange pipe 22a, that is, at positions corresponding to the ends of the fin rows, respectively. This flange 25, 25
is made of a material that is highly rigid and has as good thermal conductivity as the needle-like fins 23, and has the same diameter as the needle-like fins 23. A heat storage material such as paraffin 24 is filled around the heat exchange pipe 22a, the needle fins 23, and the flange 25.

Next, the operation of the above configuration will be explained with reference to FIG.

The operation unit 41 is used to set the heating operation, set the desired room temperature, and perform the operation start operation. Then, the control unit 40 switches the four-way valve 12, opens the on-off valve 16, and starts the compressor 11, indoor fan 19, and outdoor fan 20, respectively. In this way, when the compressor 11 is started, the refrigerant discharged from the compressor 11 is transferred to the four-way valve 12, the indoor heat exchanger 13, the on-off valve 16, the capillary tube 17, the heat exchange pipe 22b for heat radiation of the heat storage device 21,
It circulates through the check valve 18, the outdoor heat exchanger 15, and the four-way valve 12. In other words, the indoor heat exchanger 13 acts as a condenser, and the heat exchange pipe 22 for heat radiation also acts as a condenser.
b and the outdoor heat exchanger 15 act as an evaporator, and heating operation starts. At this time, heat storage device 2
The heat stored in 1 becomes heating auxiliary heat, which speeds up the rise of heating capacity.

Therefore, the control unit 30 controls the on-off valve 16 when a certain period of time has passed since the start of operation (when the heat storage is used up).
Close. Then, the refrigerant discharged from the compressor 1 circulates through the four-way valve 12 , the indoor heat exchanger 13 , the heat-absorbing heat exchange pipe 22 a of the heat storage device 21 , the expansion valve 14 , the outdoor heat exchanger 15 , and the four-way valve 12 . That is, while the indoor heat exchanger 13 and the endothermic heat exchange 22a act as a condenser, the outdoor heat exchanger 15 acts as an evaporator, and the operation shifts to normal heating operation. At this time, the heat of the high-temperature refrigerant flowing through the endothermic heat exchange pipe 22a is taken into the heat storage device 21 and stored.

As the heating operation progresses, frost gradually begins to adhere to the surface of the outdoor heat exchanger 15. Thus, the control unit 40 periodically detects the temperature of the outdoor heat exchanger 15 using the indoor heat exchanger temperature sensor 43, and opens the on-off valve 16 when the detected temperature falls below a predetermined value. At the same time, the outdoor fan 20 is turned off. Then, the heat stored in the heat storage device 21 is used as defrosting heat for the outdoor heat exchanger 15.

By the way, in the heat storage device 21, when storing heat, the paraffin 24 melts along the surface formed by the tip of each needle fin 23 and the outer surface of the flange 25, but the speed of heat transfer during the melting is different on each of the surfaces. Therefore, a solid wall is formed on the outer surface of the flange 25. Then, the paraffin 24 expands between the solid wall and the outer surface of the flange 25, and a force acts on the flange 25 in the direction of the arrow in the figure. However, since the flange 25 has high rigidity, no deformation occurs. In other words, the flange 25 acts as a shield,
To prevent the needle-like fins 23 from collapsing and deforming. Therefore, a wide fin area can be ensured, including the good thermal conductivity of the flange 25, and efficient heat exchange is always possible.

Further, during the heating operation, the control unit 40 compares the temperature detected by the indoor temperature sensor 42 and the indoor set temperature, and when the indoor temperature reaches the set temperature, the operation of the compressor 11 is turned off and the heating operation is interrupted. Thereafter, when the indoor temperature falls to a value lower than the set temperature by a predetermined value, the operation of the compressor 11 is turned on again and the heating operation is restarted.

Then, the control unit 40 energizes the electromagnetic switch 44 at the same time when the compressor 11 is turned off, and deenergizes the electromagnetic switch 44 at the same time when the compressor 11 is turned on. Therefore, when heating operation is interrupted (heat storage is interrupted), temperature switch 3
If 1 is on (heat storage temperature is below the predetermined value),
The electric heater 26 operates to generate heat, and the generated heat is stored in the heat storage device 21. This compensates for the natural heat dissipation that accompanies interruptions in heat storage, and always ensures necessary and sufficient heat storage. Incidentally, since the electric heater 26 is operated only when the compressor 11 is turned off, no economic problem arises.

In addition, although the above-mentioned Example described the heat storage device with a built-in electric heater, it can be set as appropriate whether or not to provide an electric heater. Moreover, although the case where the heat storage device is provided between the indoor heat exchanger and the outdoor heat exchanger has been described as an example, the location of the heat storage device can be set as appropriate. In addition, this invention is not limited to the above-mentioned embodiments, and various modifications can be made without changing the gist.

[Effect of idea]

As mentioned above, according to this invention, since highly rigid flanges are provided on both sides of the heat exchange pipe, deformation of the needle fins can be prevented, and efficient heat exchange is always possible. It is possible to provide a heat storage device with excellent reliability.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the configuration of a main part of an embodiment of this invention, Fig. 2 is a diagram showing the configuration of an air conditioner according to the embodiment, and Fig. 3 is a diagram for explaining the operation of the embodiment. The time chart of FIG. 4 and FIG. 5 are diagrams showing the configuration of main parts of a conventional heat storage device, respectively. 21... Heat storage device, 22a... Heat exchange pipe for heat absorption, 22b... Heat exchange pipe for heat radiation, 23... Acicular fin, 24... Paraffin (heat storage material), 25
...Flange, 26...Electric heater.

Claims (1)

[Scope of utility model registration request] In a heat storage device comprising a heat exchange pipe in which a large number of needle fins protrude radially from the outer peripheral surface, and a heat storage material is filled around the heat exchange pipe and the needle fins, both sides of the heat exchange pipe A heat storage device that is characterized by having a highly rigid flange at the bottom.