JPH06201208A - Air-conditioner - Google Patents

Abstract

PURPOSE:To devise an optimal matching of a refrigerating cycle associated with an outdoor machine in accordance with a manner, in which an indoor machine is connected to the outdoor machine. CONSTITUTION:A restriction, in which a capillary 9 and a two-way solenoid valve 8 are connected in parallel to each other, is connected to a piping midway between an expansion valve 6 in an outdoor machine 1 and an indoor machine 10 and on a side toward the indoor machine 10, and a liquid storage tank 7 is connected to the piping on a side toward the expansion valve 6 whereby switching control of the two-way solenoid valve 8 during a heating operation is determined depending on a difference in a form in which the indoor machine is combined with the outdoor machine 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner equipped with a heat pump type refrigeration cycle for performing heat exchange between air and a refrigerant to cool and heat a room.

[0002]

2. Description of the Related Art For example, many refrigeration cycles in air conditioners utilize the heat source of the atmosphere as a heat source for cooling and heating. Generally, this heat pump type air conditioner
When heating, the outdoor unit draws heat from the atmosphere, and indoor units release it. On the contrary, when cooling, the indoor unit draws heat from the atmosphere,
The outdoor unit dissipates heat into the atmosphere. By the way, regarding the indoor unit type of the housing air conditioner, various types are required from the wall-mounted type to the top-cassed type due to the recent housing situation.
It also exists. When the refrigeration cycle is viewed in principle, the low-pressure, low-temperature refrigerant flowing inside the heat exchanger of the outdoor unit during heating uniformly evaporates by exchanging heat with the surrounding atmosphere by the outdoor blower when compressed. It becomes high-temperature, high-pressure superheated steam in the machine, is cooled and condensed by indoor air by the indoor blower in the heat exchanger of the indoor unit, and returns to the low-temperature, low-pressure two-phase flow by the throttling mechanism to complete the cycle. However, speaking of the fact that all models have the same cycle, there are subtle differences in the details, such as the size of the throttle, the amount of indoor / outdoor air blowing, the size of the indoor / outdoor heat exchanger, and the amount of refrigerant charged. Not. That is, even if the cooling and heating capacities are in the same class, it is necessary to develop an outdoor unit corresponding to each indoor unit type. The cause of this is that the volume of the wall-mounted indoor unit heat exchanger has become extremely smaller than that of the ceiling-cassed type and the like due to the recent compacting of the indoor unit. If an attempt is made to optimally match the refrigeration cycle in a state where the heat exchange volumes are different, the refrigerant charge amount, the compressor rated operation Hz, etc. will naturally differ due to the heat balance of the indoor and outdoor units. In general, when the indoor unit heat exchange volume is small, the high pressure side rises and the compressor discharge temperature abnormally rises when the capacity is attempted when the amount of refrigerant is large, so the amount of refrigerant to be enclosed is reduced. In addition to the indoor unit heat exchange volume, the same problem occurs when the amount of air blown from the indoor unit is small.

[0003]

As described above, the conventional air conditioner requires the development of the outdoor unit corresponding to each indoor unit type, and the development lead time cannot be shortened. However, various problems such as huge cost remained.

Therefore, an object of the present invention is to provide an air conditioner having an outdoor unit capable of optimally matching refrigeration cycles in accordance with various connected indoor unit types. .

[0005]

In order to solve the above-mentioned problems, the present invention firstly proposes a capillary and a two-way solenoid valve on the side of the indoor unit in the middle of piping connecting the expansion valve in the outdoor unit and the indoor unit. Is connected in parallel, the expansion valve side is connected to a liquid storage tank for storing refrigerant, and the opening / closing control of the two-way solenoid valve is performed according to the difference in the indoor unit configuration combined with the outdoor unit during heating operation. The gist is that it is configured to determine.

Secondly, the gist of the first configuration is that the two-way solenoid valve is opened during the cooling operation to control the superheat of the indoor unit.

Thirdly, in the above-mentioned first configuration, when it is determined that the heat exchange capacity of the indoor unit is smaller than the reference capacity of the indoor unit and the indoor unit configuration is small during the heating operation, the two-way electromagnetic A valve is opened, and when it is determined that the heat exchange capacity of the indoor unit is larger than the reference capacity and the indoor unit configuration is large, the two-way solenoid valve is closed and the superheat control of the outdoor unit is performed. The main point is to become.

[0008]

In the above structure, first, during heating operation, the opening / closing control of the two-way solenoid valve is determined depending on the form of the indoor unit combined with the outdoor unit, thereby adjusting the amount of refrigerant stored in the liquid storage tank. It As a result, the amount of refrigerant flowing through the refrigeration cycle is controlled to an optimum amount, and a refrigeration cycle with high capacity and efficiency and optimal matching is realized in accordance with the combined indoor unit configuration.

Secondly, during the cooling operation, since the heat exchange volume of the outdoor unit, which is the condenser, is originally larger than the volume of the indoor unit, it is desirable that the amount of refrigerant enclosed in the refrigeration cycle is large. Therefore, the influence of the difference in the indoor unit form is small. Therefore, by opening the two-way solenoid valve, the amount of refrigerant stored in the liquid storage tank is adjusted to a small amount, and a refrigeration cycle with high capacity and efficiency is realized.

Thirdly, regarding the opening / closing control of the two-way solenoid valve during the heating operation, specifically, when it is determined that the indoor unit type is small, the two-way electromagnetic valve is opened, and it is determined that the indoor unit type is large. When this is done, the two-way solenoid valve is closed and the amount of refrigerant stored in the liquid storage tank is adjusted, so that a refrigeration cycle can be realized that is appropriately matched in accordance with the combined indoor unit configuration.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 schematically shows a refrigeration cycle, and shows a positional relationship between a two-way solenoid valve, a liquid storage tank, and the like. Further, FIG. 2 shows an operation control method during heating and during cooling. In FIG. 1, the outdoor unit 1 includes an outdoor heat exchanger 2,
The outdoor blower 3, the compressor 4, the four-way valve 5, the expansion valve 6, the liquid storage tank 7, the two-way solenoid valve 8 and the capillary 9, and other main components, and the indoor unit 10, the indoor heat exchanger 11 and the room It is composed of a blower 12 and the like. The throttle part in which the two-way solenoid valve 8 and the capillary 9 are connected in parallel is connected to the indoor unit 10 side in the middle of the pipe connecting the expansion valve 6 and the indoor unit 10, and the liquid storage tank 7 is connected to the expansion valve 6 in the middle of the pipe. Connected to the side. In addition, in FIG. 1, the solid line arrow indicates the refrigerant flow direction in the heating mode, and the broken line arrow indicates the refrigerant flow direction in the cooling mode. In the above refrigeration cycle, during heating operation, the high-temperature, high-pressure vaporized refrigerant discharged from the compressor 4 in the outdoor unit 1 is introduced into the indoor unit 10 after passing through the four-way valve 5, and the indoor heat exchanger 11 By exchanging heat with the indoor air by the indoor blower 12 while flowing, heat is released into the room and condensed. The condensed and liquefied refrigerant returns to the outdoor unit 1, but the refrigeration cycle in the outdoor unit 1 differs depending on the conditions for determining the indoor unit form described below. This will be described with reference to the flowchart of FIG.

During the heating operation, the indoor unit form is determined by the information that the heat exchange capacity of the indoor unit 10 is smaller than the reference capacity of the indoor unit 10 or the air blowing amount of the indoor unit 10 is smaller than the reference air blowing amount of the indoor unit 10. When it is determined that the model is compact and has a small indoor air volume (Yes in step 21), the two-way solenoid valve 8 is opened (step 22). For this reason,
The refrigerant that has returned to the outdoor unit 1 is in a state in which the two-way solenoid valve 8 is open, so that it hardly flows into the capillary 9 having a large throttle, and is bypassed to the pipe in which the two-way solenoid valve 8 is provided. And
The refrigerant having passed through the liquid storage tank 7 is throttled by the expansion valve 6 and decompressed, and then the outdoor heat exchanger 2 exchanges heat with the outdoor air by the outdoor blower 3 to complete the evaporation process. The heated low-pressure vaporized refrigerant again enters the compressor 4 and is discharged as high-temperature, high-pressure vaporized refrigerant, and one cycle of heating is completed. In this process, the expansion valve 6 performs superheat degree control defined by the temperature difference between the suction temperature of the compressor 4 and the evaporation temperature of the refrigerant passing through the outdoor heat exchanger 2 (step 24). It may be electric. In this case, the refrigerant passing through the liquid storage tank 7 is in a liquid state of high temperature and high pressure as seen in the Mollier diagram, and therefore is stored in the liquid storage tank 7 in a state of being almost full. Contrary to the above, the indoor unit type is large,
Alternatively, when it is determined that the model has a large indoor air volume (No in step 21), the two-way solenoid valve 8 is closed (step 23). Therefore, the refrigerant returned to the outdoor unit 1 flows through the capillary 9 having a large throttle because the two-way solenoid valve 8 is closed, and after passing through the liquid storage tank 7, the refrigerant is further throttled by the expansion valve 6 and depressurized. After that, the outdoor heat exchanger 2 exchanges heat with the outdoor air by the outdoor blower 3, and the evaporation process ends.
In this case, the refrigerant passing through the liquid storage tank 7 is almost not stored in the liquid storage tank 7 because it is located in a relatively low-pressure two-phase state as narrowed down by the capillary 9 as seen in the Mollier diagram.

Next, the refrigerating cycle during the cooling operation is shown in FIG.
This will be described with reference to the flowchart of (b). During cooling, the high-temperature and high-pressure refrigerant discharged from the compressor 4 of the outdoor unit 1 is guided to the outdoor heat exchanger 2 after passing through the four-way valve 5, and is cooled and condensed by the outdoor air by the outdoor blower 3. The process is complete. The high-pressure liquid refrigerant is throttled by the expansion valve 6, decompressed, and passed through the liquid storage tank 7,
Since the two-way solenoid valve 8 is in the open state (step 25), it hardly flows into the capillary 9 having a large throttle and bypasses the pipe in which the two-way solenoid valve 8 is provided. Then, by being guided to the indoor unit 10 and exchanging heat with the indoor air by the indoor blower 12 in the indoor heat exchanger 11, the heat of the indoor air is taken in the evaporation process to perform cooling. The low-pressure vaporized refrigerant enters the compressor 4 of the outdoor unit 1 and is discharged again as high-temperature, high-pressure vaporized refrigerant, and one cycle of cooling is completed. In this process, the expansion valve 6 performs superheat control which is regulated by the temperature difference between the suction temperature of the compressor 4 and the evaporation temperature of the refrigerant passing through the indoor heat exchanger 11 (step 2).
6), temperature type or electric type may be used. Thus, during the cooling operation, the two-way solenoid valve 8 is always open regardless of the indoor unit type. In this case, the refrigerant passing through the liquid storage tank 7 is located in a relatively low-pressure two-phase state by being squeezed by the expansion valve 6 as seen in the Mollier diagram.
Is hardly stored in.

The above refrigeration cycle has many advantages as follows. First, during heating, the amount of refrigerant stored in the liquid storage tank 7 can be controlled according to the indoor unit type. For example, when the indoor heat exchanger is small and the amount of air blown indoors is small as in a wall-mounted indoor unit, the liquid storage tank is small. Refrigerant is stored in 7, so the high-pressure side becomes lower than when there is no liquid tank,
An abnormal rise in compressor discharge temperature is suppressed, and a highly efficient and stable refrigeration cycle can be obtained. On the other hand, when the indoor heat exchanger is large and the amount of air blown in the room is large, as in the case cassette indoor unit, the degree of supercooling of the indoor unit can be made large, so that the heating capacity can be improved. On the other hand, during cooling, the heat exchange volume of the outdoor unit, which is a condenser, is larger than the indoor unit volume and the indoor air flow rate, and the outdoor air flow rate is large in some cases. The effect of the difference in the form of the indoor unit that is the evaporator is small. Therefore, in the refrigeration cycle of the present embodiment, the amount of refrigerant stored in the liquid storage tank 7 is small and both the capacity and the efficiency are improved. Therefore, according to the present embodiment, it is possible to provide an air conditioner having an outdoor unit capable of optimally matching refrigeration cycles in accordance with various combined indoor unit configurations.

The present invention is not limited to this embodiment, and for example, in the refrigeration cycle of FIG. 1, a capillary with a small throttle may be provided in the middle of the pipe in which the two-way solenoid valve 8 is provided. .

[0016]

As described above, according to the present invention,
First, in the middle of the pipe connecting the expansion valve in the outdoor unit and the indoor unit, the indoor unit side is connected to the throttle section in which the capillary and the two-way solenoid valve are connected in parallel, and the expansion valve side is connected to the liquid reservoir tank. Since the opening / closing control of the two-way solenoid valve is determined by the difference in the indoor unit form combined with the outdoor unit during the heating operation, the amount of refrigerant stored in the liquid storage tank is adjusted according to the combined indoor unit form, The amount of refrigerant flowing through the refrigeration cycle can be controlled to an optimum amount, and a refrigeration cycle with high capacity and efficiency and optimal matching can be realized.

Secondly, since the two-way solenoid valve is opened during the cooling operation, the heat exchange volume of the outdoor unit, which is the condenser, may be large compared to the volume of the indoor unit, and the refrigerant in the refrigeration cycle may be large. It is desirable to have a large amount of filling, and the influence of the difference in the form of the indoor unit that is the evaporator will be small, so the amount of refrigerant stored in the liquid storage tank can be adjusted to a small amount and a refrigeration cycle with high capacity and efficiency can be realized. it can.

Thirdly, regarding the opening / closing control of the two-way solenoid valve during the heating operation, specifically, when it is determined that the indoor unit type is small, the two-way electromagnetic valve is opened and it is determined that the indoor unit type is large. Since the two-way solenoid valve is closed when it is operated, the amount of refrigerant stored in the liquid storage tank is optimally adjusted according to the size of the indoor unit to be combined, and the refrigeration cycle is matched accurately. Can be realized.

[Brief description of drawings]

FIG. 1 is a diagram showing a refrigeration cycle in an embodiment of an air conditioner according to the present invention.

FIG. 2 is a flowchart for explaining an operation control method during heating and cooling in the above embodiment.

[Explanation of symbols]

 1 Outdoor unit 6 Expansion valve 7 Liquid storage tank 8 Two-way solenoid valve 9 Capillary 10 Indoor unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takayoshi Iwanaga 8 Shinsita-cho, Isogo-ku, Yokohama, Kanagawa Prefecture

Claims (3)

[Claims] 1. A throttle part, in which a capillary and a two-way solenoid valve are connected in parallel, is connected to the indoor unit side of a pipe connecting the expansion valve of the outdoor unit and the indoor unit, and refrigerant is stored on the expansion valve side. An air conditioner connected to a liquid storage tank and configured to determine opening / closing control of the two-way solenoid valve according to a difference in a form of the indoor unit combined with the outdoor unit during heating operation. 2. The air conditioner according to claim 1, wherein during the cooling operation, the two-way solenoid valve is opened to control the superheat of the indoor unit. 3. During the heating operation, when it is determined that the heat exchange capacity of the indoor unit is smaller than the reference capacity of the indoor unit and the form of the indoor unit is small, the two-way solenoid valve is opened and the heat exchange of the indoor unit is performed. When the capacity is larger than the reference capacity and it is judged that the indoor unit type is large, the two-way solenoid valve is closed to control the superheat degree of the outdoor unit. Air conditioner described.