JPH0225112B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to condensation of refrigerants such as compression type and absorption type.
This invention relates to a heat pump device that applies cooling and heating based on the principle of evaporation.

Configuration of conventional example and its problems FIG. 1 is a diagram showing the principle of a heat pump device. In the figure, reference numeral 1 denotes a pressurizing section, which is comprised of a compressor in the case of a compression type, and a generator, an absorber, etc. in the case of an absorption type. 2 is a heat exchanger, and when the refrigerant circulates according to the solid arrow in the figure, the refrigerant vapor is cooled and becomes a liquid. In other words, it functions as a condenser. The liquefied refrigerant is depressurized through the expansion valve 4, enters the heat exchanger 3, and evaporates into low-pressure refrigerant vapor. That is, the heat exchanger 3 functions as an evaporator and absorbs heat from the surroundings.

If the four-way valve 5, which is often used as a valve mechanism to reverse the flow direction of the refrigerant, is rotated 90 degrees, the refrigerant will circulate according to the broken arrow, and the heat exchanger 3 will function as a condenser, and the heat exchanger 2 will function as an evaporator. functions as

Fig. 2 shows a basic cycle shown in Fig. 1 in which a heat exchanger 7 for exchanging heat with the heat storage material 6 is provided between the heat exchanger 2 and the pressurizing section 1, and in the cycle indicated by the solid arrow, the condenser A part of the condensation heat released in step 2 is stored in the heat storage material 6 in the heat storage device 8. This is primarily useful in heating cycles, where heat exchanger 2 is located indoors to warm the room, and heat exchanger 3 is located outside to draw heat from the outside air. At this time, if the outside air temperature is low, frost will gradually form on the heat exchanger 3, making it impossible to take in heat from the outside air.

Therefore, when the four-way valve is rotated 90 degrees to create a cooling cycle, the heat exchanger 3 becomes a condenser and generates heat, which removes frost. However, at this time, the heat exchanger 2 becomes an evaporator, so the space that should be heated is cooled, which is extremely inconvenient. Therefore, for example, if the fan 9 of the heat exchanger 2 is stopped to prevent the refrigerant from evaporating in this heat exchanger, in the case of the basic configuration shown in FIG. This may cause inconveniences such as breaking the machine. However, in the case of having the heat storage device 8 shown in the figure, the unevaporated refrigerant is heated by the heat exchanger 7 by the heat stored in the heat storage material 6, and the unevaporated refrigerant evaporates, which has a negative effect on the pressurized section. I won't give it. This is the so-called defrost cycle.

Although this method is good in principle, the actual defrosting time must be short, so if the heat exchanger 7 is provided with such heat transfer characteristics, the heat output will be almost all of the heat at the start of heating operation. Since the heat is transferred from the exchanger 7 to the heat storage material 6, there was a problem in that no output was output to the heat exchanger 2.

One solution to this problem is to increase the heat storage capacity, increase the heat storage average temperature, and narrow the operating temperature range, thereby creating a small temperature difference during heat storage and a large temperature difference during heat dissipation. The disadvantage is that it requires a large amount of heat to raise the average temperature, so if the operation is stopped for a certain amount of time, for example, the temperature of the heat storage tank will drop considerably between when the operation is stopped at bedtime and when it is started the next day. Unless the insulation is good, the temperature will drop to close to the outside air temperature, so at startup there will be a large difference between the temperature of the heat storage material and the condensation temperature, and the heat exchanger 2 will have no output, or the output will be significantly reduced, and at this stage the heat storage The total amount of heat that must be stored in the container is several times the amount of heat required for one defrost operation, resulting in a reduction in output over a considerable period of time.

Object of the Invention The object of the present invention is to improve the heating start-up characteristics and defrosting characteristics of a heat pump device having a heat storage device.

Structure of the Invention The present invention provides a heat storage device having a vertically elongated shape, filling the lower part with a heat storage material, leaving a gas phase part in the upper part, and providing a heat exchanger in the part filled with the heat storage material and the gas phase part. These heat exchangers are connected in series or in parallel and placed between the indoor heat exchanger 2 and the four-way valve.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention is shown in FIG. In FIG. 3, the heat storage tank is vertically elongated, and a heat storage material 6 is filled in the lower part of the tank. The heat storage material 6 may be a liquid substance alone having a vapor pressure of about 0.1 kg/cm ² or more at room temperature, or may be a mixture of a substance 13 having a large heat storage capacity.

The upper part of the thermal storage tank is a space filled with vapor of the filled substance.

On the other hand, the heat exchanger 12 is provided in the heat storage material portion, and the heat exchanger 11 is provided in the gas phase portion 10, and in this embodiment, they are connected in series, and in the heating cycle, the four-way valve 5 , passes through the heat exchanger 12 at the bottom, passes through the heat exchanger 11 in the gas phase,
It reaches the indoor condenser 2. During defrosting operation, the liquid passes directly through the indoor unit 2 according to the dashed arrow, and reaches the four-way valve 5 via the heat exchanger 11 and the heat exchanger 12.

Here, the heat exchanger 12 at the bottom is the heat storage material 6
Let be the ability to store the amount of heat required for defrosting within the assumed defrosting time interval. Therefore, this heat exchanger 12 may have a very small capacity and therefore be small.

On the other hand, the heat exchanger 11 provided in the gas phase section 10 is effective in extracting heat, and its capacity and size are determined so that the necessary amount of heat can be extracted from the heat storage material 6 within the set defrosting time. There is a need.

The function of the example shown in FIG. 3 will be explained. In this figure, the solid arrow indicates the state of the heating cycle mentioned above, but the high-pressure refrigerant vapor first enters the heat exchanger 12 at the bottom of the heat storage device, and the refrigerant vapor is cooled or partially condensed. However, since the heat transfer area of this portion is not made very large, the temperature of the heat storage material 6 is increased relatively slowly. In Figure 3, heat storage material 6
A heat exchanger 12 is installed near the bottom of the chamber, and the heat storage material 6 is warmed by convection, so in order to achieve a sufficiently slow speed, this heat exchanger 12 may be extremely small. . Next, the refrigerant is in the gas phase part 10
The gas enters the heat exchanger 11 located in the air, but the specific heat of the gas is small and the gas is sent to the condenser 9 without releasing almost any heat.

In this way, in the heating cycle, the thermal energy of the refrigerant vapor is stored in the heat storage material 6 in very small amounts.

Therefore, the amount of heat transferred from heating output to heat storage per unit time is small, and is not so large as to cause a perceived decrease in heating capacity.

Next, during defrosting operation, the refrigerant flows according to the dashed arrow, and since the fan 9 of the indoor heat exchanger is stopped, unevaporated liquid refrigerant flows into the heat exchanger 11 to cool the indoor heat exchanger. The vapor in the gas phase part 10 is cooled and liquefied, and drips onto the heat storage material 6, but since the temperature here is high in the heat storage state, the dropped liquid evaporates again.
Further, it is cooled by a heat exchanger 11. As described above, in the defrosting cycle, the heat exchanger 11 placed in the gas phase plays a major role, rapidly drawing out the stored energy and using it to evaporate the liquid refrigerant. The heat exchanger 12 located inside the heat storage material also transfers heat from the heat storage material, but the heat exchanger 11 that uses condensation heat transfer is the main player.

On the other hand, as mentioned earlier, the heat exchanger 11 is of little use in storing heat, so its heat transfer characteristics should be sized so that the necessary thermal energy can be extracted for the required defrosting time. Often, this size has little effect on the rate of heat storage. In addition, in FIG. 3, 14 is a gas phase interface.

Effects of the Invention As described above, according to this configuration, both the heat exchanger 12 provided in the heat storage material and the heat exchanger 11 provided in the gas phase are relatively small, and yet There is a big difference in heat transfer characteristics, and during heating operation, a part of the output is stored in the heat storage device very gradually.
During defrosting, the thermal energy stored in the heat storage is released in a short period of time, and the speed of heat storage and heat radiation does not change depending on the temperature difference, so the temperature range of heat storage and heat radiation can be widened. It has the advantage of being smaller and having less heat loss.

Furthermore, since the heat storage material can be a mixture of solid and liquid, even if a substance with a large heat storage capacity due to phase change is used, the heat transfer characteristics of the heat exchanger are not affected, and furthermore, the heat storage tank can be made smaller.

Furthermore, since condensation heat transfer is used to extract heat, there is an advantage that heat can be extracted in a short time and the heat exchanger can be constructed with a small size.

[Brief explanation of drawings]

FIG. 1 is a principle diagram of a heat pump, FIG. 2 is a refrigerant circuit diagram of a conventional heat pump device having a heat storage device, and FIG. 3 is a refrigerant circuit diagram of a main part of a heat pump device of the present invention. DESCRIPTION OF SYMBOLS 1... Pressurization part, 2, 3... Heat exchanger, 4... Expansion valve, 5... Four-way valve, 6... Heat storage material, 8... Heat storage device, 10... Gas phase part in the heat storage tank , 11... Heat exchanger provided in the gas phase section, 12... Heat exchanger provided in the heat storage material, 13... Substance with large heat storage capacity.

Claims (1)

[Claims] 1. A refrigerant circulation path is formed by a heat exchanger section in which a pressurizing section converts low-pressure refrigerant vapor into high-pressure refrigerant vapor, and two heat exchangers are connected in series via an expansion valve in the middle,
A valve mechanism is provided between the pressurizing section and the heat exchanger section to reverse the flow direction of the refrigerant flowing through the heat exchange section, and the heat exchanger on the upstream side of the flow of the refrigerant is used as a condenser and serves as a heat radiation source. A heat storage device capable of exchanging heat with the refrigerant circuit is provided between one end of the heat exchange section and the valve mechanism when the side is used as an evaporator and a heat absorption source, and this heat storage device is a vertically elongated heat storage tank, with a A heat pump device in which a heat storage material is filled leaving a gas phase portion, and a heat exchanger for flowing the refrigerant is provided in a portion buried in the heat storage material and the gas phase portion, and these are connected in series.