JPH0730968B2 - Heat pump - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a heat pump, and more particularly to an improvement of a heat pump including a heat storage material that stores excess heat during operation and releases the stored heat to a refrigerant passage when necessary. .

[Technical background of the invention and its problems]

As is well known, a heat pump is a combination of a compressor, a condenser, an expansion valve, an evaporator, and the like. Since it can be used for cooling only by switching the refrigerant flow path, it is widely used for heating homes and the like. There is.

By the way, when such a heat pump is used for heating, it usually requires a considerable amount of time from the start of operation until hot air is blown out. This is because refrigeration cycle parts such as the compressor are cold at the start of operation. For residents, it is desirable that hot air be blown out from the start of operation, and in order to meet such demands, an electric heater is usually installed in the case of the compressor, and the electric heater is energized at the same time as operation starts. The method of shortening the time until hot air is blown out is adopted. However, the method of mounting the electric heater as described above is not a preferable method in terms of energy saving because the electric heater consumes power.

Therefore, in order to eliminate such a problem, recently, excess heat during heating operation is stored in a heat storage material, and the heat is released at the start of operation on the next day to shorten the time until hot air is blown out. A proposal has been made to try.

However, the above-mentioned method of providing the heat storage material has the following problems. In other words, the prerequisite for realizing this method is to store heat stably in the heat storage material for a long time. In order to satisfy this condition, the heat storage tank must be constructed with a sufficient heat insulating structure in order to suppress heat radiation loss from the heat storage tank containing the heat storage material. For this reason, it was difficult to put it into practical use in terms of the overall price increase associated with the heat insulating structure and the overall size increase that would result from the heat insulating structure.

[Object of the Invention]

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a heat pump that can be downsized and reduced in price without impairing the features of the heat storage system. is there.

[Outline of Invention]

According to the present invention, a heat pump body formed by combining a compressor, a condenser, an expansion valve, an evaporator, and the like, a heat storage tank that houses the compressor therein, and a heat storage tank that is housed in the heat storage tank, During operation, it receives heat from the compressor and is heated above its melting point, and after operation of the compressor is stopped, it is cooled to below its melting point at the outside air temperature through the wall of the heat storage tank, and a stable supercooled state is maintained. There is provided a heat pump including: a latent heat storage material to be held; and a stimulus applying means for stimulating the latent heat storage material to release heat from the latent heat storage material when the heat pump main body starts operating.

〔The invention's effect〕

There are various latent heat storage materials. Among them, when they are heated to a temperature above the phase change temperature (melting point) Tm and liquefied and then cooled to below Tm, they do not solidify at Tm but become a liquid at a temperature lower than Tm. Some are in a cooling state and can maintain this supercooled state in a stable manner. An example of such a latent heat storage material is a sodium acetate-based hydrated salt. When a latent heat storage material in a supercooled state is stimulated in this way, all of it rapidly solidifies, and at this time latent heat is released. The heat pump according to the present invention utilizes the above-mentioned phenomenon. That is, as an example, the latent heat storage material is heated to the phase change temperature Tm or higher by the surplus heat during the operation on the previous day. The latent heat storage material is cooled to a supercooled state as the outside air temperature decreases at night between the time the operation is stopped and the next day the operation is started.
At the start of operation on the next day, the latent heat storage material is stimulated to release the stored heat, and this heat causes the refrigerant in the compressor to rapidly rise in temperature. Therefore, it is possible to shorten the time from the start of operation to the time when hot air is blown out. In this case, a heat storage tank containing a compressor is provided inside, and the latent heat storage material having the above characteristics is stored in the heat storage tank. Therefore, the heat generated in the compressor is efficiently converted into the latent heat storage material. Not only can it be transmitted, but since it is not necessary to insulate the heat storage tank containing the latent heat storage material from the outside air, it is possible to achieve overall downsizing and cost reduction.

Example of Invention

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic configuration of a heat pump according to an embodiment of the present invention. That is, in the figure, 1 is a compressor, 2 is a heat exchanger with a blower that is placed indoors and is used as a condenser during heating operation and as an evaporator during cooling operation, and 3 is placed outdoors. Shows a heat exchanger with a blower that is used as an evaporator during heating operation and as a condenser during cooling operation, 4 is a four-way valve for switching between heating and cooling operations, and 5 is an expansion valve. .

As shown in FIG. 2, the compressor 1 is housed in a heat storage tank 6 made of a metal material or the like. And
The latent heat storage material 7 is accommodated in the heat storage tank 6 at a level at which most of the compressor case is submerged. As the latent heat storage material 7, a material having a phase change temperature of about 30 ° C. and maintaining a stable supercooled state, for example, a sodium acetate hydrate salt is used. That is, as shown in Fig. 3, when cooled from the state heated above the phase change temperature Tm, it does not solidify at Tm and maintains a supercooled state to a temperature below Tm stably, and in this state the stimulation is The one that becomes Tm when given and starts coagulation is used. Heat storage tank 6
Inside, a stimulus applying mechanism 8 is arranged above the latent heat storage material 7 as shown in FIG. This stimulus applying mechanism 8 has a lever 9 having a center portion rotatably supported, a needle N at one end side through which a tip portion can enter the latent heat storage material 7, and an iron piece I at the other end side. A spring 10 that constantly applies a force to the lever 9 in the direction of moving away from the latent heat storage material 7 with respect to the lever 9, and the iron piece I is attracted to the needle N when the spring 10 is arranged at a position facing the iron piece I and is biased. And an electromagnet 11 for intruding into the latent heat storage material 7. Then, the electromagnet 11 and the compressor 1 are controlled by the control device 12 in a relationship described later.

Next, the operation of the heat pump configured as above will be described.

First, it is assumed that heating operation has already been performed. At this time, the refrigerant flows in the path of the compressor 1, the four-way valve 4, the heat exchanger 2, the expansion valve 5, the heat exchanger 3, the four-way valve 4 and the compressor 1.
Since the refrigerant compressed by the compressor 1 is kept at high temperature,
The hot air is blown out from the heat exchanger 2 through which the high-temperature refrigerant flows, and eventually the room is heated. At this time, the latent heat storage material 7 in the heat storage tank 6 is the compressor 1
Is heated above the phase change temperature Tm by heat conduction from the case of
It is kept in a liquid state.

The heating operation as described above can be stopped at any time when heating is no longer required, but it is assumed that the heating operation is stopped at the time to shown in Fig. 4 along with sleep. When stopped in this way, the latent heat storage material 7 is cooled by the outside air, and the temperature thereof gradually decreases. In this case, since the latent heat storage material 7 having the above-described characteristics is used, the latent heat storage material 7 retains the liquid state even when cooled to the phase change temperature Tm or lower. That is, the supercooled state is stably maintained.

Then, when the command is given to the controller 12 at the time t ₁ shown in FIG. 4 in order to start the heating operation the next morning, the controller 12
Activates the compressor 1 and simultaneously energizes the electromagnet 11 for a short period of time. When the electromagnet 11 is energized, the lever 9 rotates and the needle N enters the latent heat storage material 7 to give a stimulus to the latent heat storage material 7. When the stimulus is applied in this manner, the latent heat storage material 7 instantly rises in temperature to the phase change temperature Tm, starts solidification, and releases the latent heat stored up to now. The released heat is conducted through the case of the compressor 1 to heat the refrigerant inside the compressor 1. For this reason, after a very short time has passed from the start of the operation, warm air is blown from the heat exchanger 2, and heating with high comfort is performed there.

In this way, warm air can be blown out in a short time from the start of operation, which contributes to comfortable heating. In this case, since the latent heat storage material 7 having the above-mentioned characteristics is used and the latent heat storage material 7 is cooled to the supercooled state by the outside air, it is not necessary to insulate the heat storage tank 6 from the outside air. Absent. For this reason, it is possible to prevent the price increase and the size increase of the whole, which are likely to occur when the heat storage method is adopted, and in the end, the above-mentioned effects can be exhibited.

It shows yet another embodiment of the present invention. Also in this figure, the same parts as those in FIG. 1 are denoted by the same reference numerals. Therefore, the description of the overlapping parts will be omitted.

In this embodiment, a valve 20 is interposed between the suction port of the compressor 1 and the four-way valve 4. Then, the heat exchanger 21 is arranged in the accommodation space of the latent heat storage material 7 accommodated in the heat storage tank 6 so as to come into contact with the case of the compressor 1.
Is connected to the suction port of the compressor 1 and the other end is connected to the inlet side of the valve 20 via the valve 22. The valves 20 and 22 and the stimulus applying mechanism 8 are controlled as follows by a controller (not shown) according to the operation mode.

That is, during heating operation, the valve 20 is controlled to be opened and the valve 22 is controlled to be closed. At this time, the latent heat storage material 7 is heated to the phase change temperature Tm or higher by the surplus heat. And when the heating is stopped,
The latent heat storage material 7 is cooled by the outside air and maintains a supercooled state. Next, when the heating operation is started, the valve 20 is controlled to be opened and the valve 22 is controlled to be closed. Simultaneously with the start of the heating operation, the stimulus applying mechanism 8 is energized and the supercooled state of the latent heat storage material 7 is released. Since the refrigerant is heated by this release, the rising at the start of heating is accelerated as in the case of the above embodiment. When defrosting is performed during the heating operation, the valve 20 is controlled to be closed and the valve 22 is controlled to be open. At the same time, the stimulus applying mechanism 8 is energized for a short time, and the four-way valve 4 is switched to operate in the reverse cycle. To be done. Even with this structure, the same effect as that of the above embodiment can be exhibited.

Further, in each of the above-described embodiments, a so-called mechanical stimulating system is adopted as a means for stimulating the latent heat storage material 7, but as shown in FIG. , 31b may be inserted and a current may be passed between the electrodes 31a, 31b to give a stimulus, or a chemical stimulus may be given. Further, in each of the above-described embodiments, the stimulus is applied at the same time as the heating operation is started, but the stimulus may be applied before the compressor is driven. Of course, various modifications can be made without departing from the scope of the present invention.

[Brief description of drawings]

FIG. 1 is a schematic system diagram of a heat pump according to an embodiment of the present invention, FIG. 2 is a diagram for explaining a relationship between a compressor and a latent heat storage material in the same embodiment, and FIG. The figure for demonstrating the characteristic of the latent heat storage material used, FIG. 4 is a figure for demonstrating operation | movement of the same Example, FIG. 5 is the principal part in the heat pump which concerns on another Example of this invention. FIG. 6 is a schematic system diagram for explaining a modification of the stimulus applying means. 1 ... Compressor, 2, 3 ... Heat exchanger, 4 ... Four-way valve, 5 ... Expansion valve, 6 ... Heat storage tank, 7 ... Latent heat storage material, 8 ... Stimulation mechanism, 1
2 ... Control device.

Claims (2)

[Claims] 1. A heat pump main body comprising a compressor, a condenser, an expansion valve, an evaporator and the like in combination, a heat storage tank containing the compressor therein, and a heat storage tank housed in the heat storage tank to operate the compressor. Inside is heated to above the melting point by receiving heat from the compressor, and after operation of the compressor is stopped, it is cooled to below the melting point at the outside air temperature through the wall of the heat storage tank and maintains a stable supercooled state. A heat pump, comprising: a latent heat storage material for storing heat and a stimulus applying means for stimulating the latent heat storage material to release heat from the latent heat storage material when the heat pump body starts to operate. 2. The heat pump according to claim 1, wherein the stimulus applying means is one kind selected from means for applying mechanical, electrical and chemical stimuli.