JPS6342174B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an energy-saving air conditioner that performs cooling operation using a compression refrigeration cycle and heating operation using a natural circulation refrigerant cycle. The present invention relates to an air-conditioning/heating machine that can automatically adjust the amount of refrigerant to be circulated according to the difference in the amount of refrigerant required for cooling and heating, as well as changes in the load during operation.

In this type of air conditioner, especially in heating operation using a natural circulation refrigerant cycle, if the receiver has only a liquid reservoir function, the amount of refrigerant cannot be adjusted sufficiently, and the There are drawbacks such as full refrigerant and the inability to perform any adjustment functions, high pressure increases due to too much refrigerant, and decreased capacity due to insufficient refrigerant, making it difficult to operate stably and at proper capacity. Ta.

In order to deal with such problems, the present applicant has developed a structure in which a refrigerant amount regulator is interposed in the refrigerant circuit, in which an accumulator and a liquid reservoir are provided for heat exchange. We have developed and proposed a device that can overcome the various defects caused by
The refrigerant amount regulator in this case is typified by a heat exchanger type accumulator as shown in Figs. It has a structure.

In the refrigerant amount regulator 6' having such a structure, the area of the upper and lower partitions is relatively small, so heat exchange between them is not sufficient, and the height is quite high, occupying a large installation space. Unavoidable drawbacks include the increased size of the outdoor unit and the fact that the volume of the liquid storage container 6a' is smaller than the size of the accumulator 6b', so that the liquid storage function cannot be fully demonstrated.

Also, if we try to increase the heat exchange area in the partitions that separate each other, and create a structure in which the amount of heat exchange can change depending on the amount of stored refrigerant,
As shown in FIG. 6, the partitions had to have a complicated shape, which was undesirable as it led to increased costs.

The present invention focuses on such problems and provides an improved refrigerant amount regulator that has a simple structure and can satisfactorily perform the desired refrigerant amount control function, by interposing it in the refrigerant circuit. This makes it possible to further improve the operating characteristics of this type of energy-saving air conditioner.

In order to clarify the specific contents of the present invention, the present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

FIG. 1 shows a developed piping system of a separate air conditioner/heater according to an example of the present invention. This air conditioner has an outdoor unit 1, an indoor unit 2, and a refrigerant circuit between the It is composed of two connected refrigerant pipes 11 and 12.

The outdoor unit 1 is equipped with a compressor 3, a condenser/refrigerant heating coil 4, a pressure reducer 5 consisting of, for example, a capillary reach tube, a refrigerant amount regulator 6, a heating device 7, and a refrigerant circuit switching device. Unit 2 includes an indoor coil 8 and an indoor fan 1.
It is equipped with 4.

The outdoor unit 1 is installed outdoors on the ground or in a low place such as the floor of a machine room where outside air can circulate.
The indoor unit 2 is placed at a suitable position higher than the outdoor unit 1, such as on the upper part of the indoor wall.

In the outdoor unit 1, the condenser/refrigerant heating coil 4 forms an air-to-air type fan coil unit by a heating device 7, such as a combustor, and an outdoor fan 13, which can exchange heat with each other. The refrigerant heating coil 4 has a vertical level difference between both ends of the heat transfer tube, and follows a path in accordance with the direction of gravity between the high-position side tube end 4a and the low-position side tube end 4b. During cooling operation, the outdoor fan 13 is energized without using the heating device 7 to exchange heat between the refrigerant in the coil and the outside air, forming a condenser, and during heating operation, the refrigerant is heated by the heating device 7. Heat exchange is performed between the high-temperature air and the refrigerant in the coil, and the refrigerant heater also serves as a condenser.

On the other hand, the indoor coil 8 in the indoor unit 2
There is a difference in the upper and lower levels between the ends of the heat transfer tube,
It is provided so as to follow a path in accordance with the direction of gravity between the high-position side tube end portion 8a and the low-position side tube end portion 8b.

Next, the refrigerant circuit switching device can be of various forms in which a solenoid valve and a check valve are combined, but the example shown in FIG. A check valve 22 interposed in the pipe connecting the position side pipe end 4a, and a solenoid valve 9 interposed in the pipe connecting the suction side of the compressor 3 and the outlet side of the check valve 22. , and a check valve 10 connected in parallel to the pressure reducer 5. By closing the solenoid valve 9, the compressor 3 → check valve 22 → condenser and refrigerant heating coil 4 (in this case, the condenser ) → pressure reducer 5 → refrigerant piping 12 → indoor coil 8
→ Accumulator 6b of refrigerant amount regulator 6 → Compressor 3 Enables cooling operation using a compression refrigeration cycle in which refrigerant is forcibly circulated in a closed circuit. 4 (acts as a heater in this case) →
High-position side pipe end 4a of the coil 4 → solenoid valve 9 → accumulator 6b → refrigerant pipe 11 → indoor coil 8
High-position side pipe end 8a → indoor coil 8 → low-position side pipe end 8b of the coil → refrigerant pipe 12 → check valve 1
0→low-position side pipe end 4b of refrigerant heating coil 4→refrigerant heating coil 4, and has a switching function that enables heating operation in a natural circulation heating cycle in which refrigerant is naturally circulated.

Next, as is clear from FIG. 2 and FIG. 3, the refrigerant amount regulator 6 uses a heat conductive material such as a vertically long double cylindrical sealed container arranged so as to be exposed to the outside air. It is divided into two chambers, an inner chamber and an outer chamber, which are arranged concentrically and are capable of mutual heat exchange by an intermediate partition cylinder 17 consisting of an inner chamber, and the inner chamber is surrounded by an accumulator 6b. It has a structure in which the outer chamber is formed as a liquid reservoir container 6a.

The liquid storage container 6a is connected to the refrigerant pipes through which the low-pressure liquid refrigerant fed to the indoor coil 8 during cooling operation and the condensed liquid refrigerant after heat exchange with the indoor coil 8 during heating operation respectively. Branch pipe 21
While branch connection is made by the accumulator 6b
The low-pressure gas refrigerant that has undergone heat exchange with the indoor coil 8 during cooling operation is interposed in the refrigerant gas pipes through which the vaporized refrigerant to be supplied to the indoor coil 8 during heating operation flows.

In addition, in order to make the accumulator 6b have a structure having a gas-liquid separation function, the communication pipes 18 and 19 are set up in the vessel so that each opening end is opened in the upper part, and the communication pipe 18 is provided with a A small hole 18a for liquid inflow during heating that communicates with the lower part of the container
In addition, each of the communication pipes 19 has small holes 19a for returning oil during cooling, which communicate with the lower part of the vessel, so that the amount of refrigerant liquid stored in the accumulator 6b can be adjusted. There is.

The concrete structure of the refrigerant amount regulator 6 will be explained with reference to FIGS. 2 and 3. The container body, which is a double cylinder, has an outer cylinder made up of three members: a cylindrical portion 23, an upper end plate 24, and a lower end plate 25. are fixed together by welding to form a pressure vessel, and on the other hand, the inner cylinder is made up of two members: a cylindrical part 26 and an upper end plate 27, which are erected from the inner center of the lower end plate 25 by welding. The pressure vessel is fixed together by welding and is arranged approximately concentrically with the outer cylinder.

The communication pipes 18 and 19 are accommodated in the inner cylinder, and their respective extraction portions are hermetically inserted through the side walls of the cylindrical portions 26 and 23 to be drawn out laterally.

Further, an outlet pipe for connecting to the branch pipe 21 is pulled out from the bottom of the outer cylinder which becomes the liquid reservoir 6a, and an outlet pipe to connect to the side pipe 20 which will be described later is drawn out from the side wall of the inner cylinder which becomes the accumulator 6b. The cylindrical portion 23 is provided with air passing through it and drawn out to the side.

The upper opening ends of the communication pipes 17 and 18 are formed into diagonal cuts so as to face each other, and a partition wall 28 hanging from the upper mirror plate 27 is interposed between the two diagonal cuts. Due to the partition wall 28 and the structure of the diagonal cut, the connecting pipe 1
The configuration is such that no short-circuit flow of refrigerant occurs between 7 and 18.

Furthermore, in the outdoor unit 1, a solenoid valve 15 and a high-pressure control valve 16 are connected in series in a side pipe 20 provided so as to be able to communicate with the gas phase portion of the accumulator 6b and the low-position side pipe end 4b of the refrigerant heating coil 4. There is no intervention.

The solenoid valve 15 is for opening during heating operation, and the high-pressure control valve 16 is for controlling two chambers separated by a bellows connected to the valve, one of which is kept under atmospheric pressure, and the other is used within the system. It is designed to be placed under the same refrigerant pressure as the refrigerant. For example, when Freon-22 is used as the refrigerant,
Fully open with the valve inlet at 23.5Kg/cm ² gauge.
23.0Kg/cm A control valve that operates fully closed when the gauge is ² , and when the pressure inside the valve body exceeds a predetermined pressure relative to atmospheric pressure, the valve opening changes in proportion to the pressure difference. It forms an automatic pressure regulating valve.

Next, the operation of the air conditioner will be explained.

(a) Heating operation: The compressor 3 is stopped, the outdoor fan 13 and the indoor fan 14 are energized, the heating device 7 is in heating operation, and the solenoid valve 9 is opened.

The liquid refrigerant in the refrigerant heating coil 4 exchanges heat with the air heated by the heating device 7, evaporates, and becomes a high-temperature gas refrigerant.

This high-temperature gas refrigerant flows from the high-position side pipe end 4a to the solenoid valve 9, the accumulator 6b, and the refrigerant pipe 11.
The refrigerant flows into the indoor coil 8 from the high-position side pipe end 8a, heats the room by exchanging sensible heat and condensation latent heat with the indoor air sent by the indoor fan 14, and the refrigerant itself is condensed and liquefied. After flowing down in the indoor coil 8 according to gravity, the refrigerant flows into the refrigerant heating coil 4 from the low-position side pipe end 4b via the low-position side pipe end 8b, the refrigerant pipe 12, and the check valve 10, It is reheated by the heating device 7 and evaporated.

In this way, the natural circulation of the refrigerant accompanied by a gas/liquid phase change occurs as shown by the solid line arrow in FIG. 1, thereby efficiently heating the room.

Since the inside of the accumulator 6b is a superheated gas region, it hardly exists in a liquid state, and the partition cylinder 17 is in contact with this superheated gas.

Therefore, the inside of the liquid reservoir 6a, which is in communication with the refrigerant pipe through which the condensed refrigerant flows, is heated by the superheated gas via the partition shell 17.

On the other hand, the inside of the liquid reservoir 6a is cooled by outside air via the peripheral wall.

As a result, the amount of refrigerant liquid can be adjusted in the liquid storage container 6a to match the difference between cooling by outside air and heating by superheated gas.

For example, when there is too much refrigerant in the natural circulation system, the degree of superheating of the refrigerant decreases, the evaporation power for the liquid storage container 6a decreases, and the amount accumulated in the container 6a increases.

When the amount of refrigerant in the natural circulation system decreases, the degree of superheating of the gas increases, and the amount of refrigerant stored in the liquid reservoir 6a tends to decrease.

As a result, a balance is finally reached with an appropriate accumulation amount, and in this way, the refrigerant in the natural circulation system is maintained at an appropriate amount.

During this heating operation or immediately after startup, the amount of circulating refrigerant may be large and the refrigerant temperature and pressure at the outlet of the refrigerant heating coil 4 may rise abnormally, and when the system pressure rises, the high pressure control valve 16 adjusts to this pressure. Twist it open and pour the liquid refrigerant into the accumulator 6.
B, the amount of refrigerant in the system is reduced, and the pressure is adjusted so that it does not rise above the set level.

Since the refrigerant accumulated in the accumulator 6b flows out from the small hole 18a provided in the communication pipe 18,
The inflow amount and the outflow amount are balanced when the liquid level in the accumulator 6b reaches a certain value, and thus the system pressure can be stably adjusted.

Needless to say, when the pressure in the system decreases, the refrigerant liquid in the accumulator 6b flows into the system through the small holes 18a to prevent the pressure from decreasing.

As is clear from the pressure regulating function of the high pressure regulating valve 16, the amount of refrigerant in the accumulator 6b during heating is adjusted during a transient situation at startup or during heating overload; The refrigerant amount adjustment function in the liquid storage container 6a is controlled by the refrigerant heating coil 4 under normal operating conditions.
It will be fully understood from the above explanation that this is done in accordance with the degree of superheating of the refrigerant.

(b) Cooling operation: When the compressor 3, outdoor fan 13, and indoor fan 14 are operated with the heating device 7 stopped and the solenoid valve 9 closed, high-pressure and high-temperature refrigerant gas discharged from the compressor 3 The refrigerant reaches the condenser and refrigerant heating coil 4, where it is cooled by the outdoor fan 13 and condensed into liquefaction.Then, the pressure is reduced by the pressure reducer 5 and it becomes a low-pressure liquid refrigerant, which passes through the refrigerant piping 12 and reaches the indoor coil 8, where it is heated indoor While the room is cooled by exchanging heat with the air, the refrigerant itself evaporates and flows through the refrigerant pipe 1.
1. It reaches the suction side of the compressor 3 via the accumulator 6b.

At this time, the refrigerant flow is as indicated by the broken line arrow in FIG. 1, and cooling operation is performed by the compression refrigeration cycle.

Since the inside of the accumulator 6b is a low-pressure superheated gas region, the liquid reservoir 6a is cooled through the partition shell 17. Further, the container 6a is heated by outside air through the peripheral wall, and the heating operation is reversed.

When the cooling load is high due to a rise in room temperature, the amount of heat exchanged in the indoor coil 8 is large, so the degree of superheating of the suction gas becomes large, and therefore a low pressure is generated in the liquid reservoir 6a, which is in almost the same state as the outlet of the pressure reducer 5. When refrigerant liquid accumulates, this refrigerant is heated and evaporated, so that only gas refrigerant exists in the container 6a and does not become liquid and accumulate, and the required amount of refrigerant suitable for high loads is supplied to the refrigerant circuit. circulate within.

On the other hand, when the cooling load is low due to a drop in room temperature, the amount of heat exchanged in the indoor coil 8 is small and the degree of superheating of the suction gas is small. As a result of the suction gas temperature being rather low compared to the refrigerant temperature, an amount of refrigerant liquid corresponding to the difference between cooling by the partition cylinder 17 and heating by the peripheral wall is stored in the liquid storage container 6a, thus reducing the cooling load. The required amount of refrigerant is circulated within the system.

As mentioned above, both the heating and cooling liquid storage containers 6
A adjusts the surplus refrigerant according to the required amount of refrigerant, and by forming the partition cylinder 17 as the inner wall of the double longitudinal container as shown in the figure, the increase or decrease of the heat exchange surface commensurate with the amount of liquid can be achieved reliably. As a result, the refrigerant amount adjustment function is performed properly and stably.

Note that the communication pipes 18, 1 in the refrigerant amount regulator 6
In addition to the piping configuration shown in FIG. 1, various modifications such as those illustrated in FIGS.
As for the arrangement form, it is desirable to have a substantially concentric structure, and various modifications illustrated in FIG.
Furthermore, seven variations of the ones shown in FIG. 4, which are vertically reversed, are also applicable.

As mentioned above, in the air conditioner illustrated in FIG. 1, the refrigerant heating coil is formed into an air-facing type that can also be used as a condenser during cooling. Of course, the refrigerant heating coil may be formed in the form of a hot water boiler in which the heat source of a combustion device such as a gas burner is transferred to the refrigerant using water as a medium. Needless to say, such modifications are also included in the present invention.

As is clear from the above explanation, the air conditioner of the present invention performs the heating operation by a natural circulation heating cycle in which the refrigerant heated by the heating device 7 is naturally circulated between the refrigerant heating coil and the indoor coil 8. The cooling operation is performed by a compression refrigeration cycle in which refrigerant is forcedly circulated between the outdoor unit 1 and the indoor unit 2, and both operations use a common refrigerant, and the two units 1 and 2 are connected to each other using a compression refrigeration cycle. Since the structure is made up of refrigerant pipes 11 and 12, only two connecting pipes are required during installation work at the installation location, which is extremely effective in simplifying the work. Furthermore, during heating operation, the operation of the compressor 3 is stopped and heating can be performed by natural circulation, so power consumption is kept low, making it suitable as an energy-saving device.

Furthermore, the present invention provides a refrigerant amount regulator 6 in the refrigerant system, which is made up of a liquid reservoir 6a and an accumulator 6b, which are capable of exchanging heat between them, so that the amount of surplus refrigerant during steady operation can be adjusted to the liquid reservoir 6a. Since the refrigerant is stored in the refrigerant, an appropriate amount of refrigerant can be obtained for both cooling and heating, and various problems caused by an excess or deficiency of refrigerant can be solved, and highly stable operation can be achieved.

Further, since the amount of refrigerant required for cooling and heating can be adjusted by using the liquid storage container 6a,
Appropriate and fully capable operation of both cooling and heating can be ensured.

Particularly, in the present invention, the refrigerant amount regulator 6 is formed into a substantially concentric double cylinder so that mutual heat exchange is performed by the partition cylinder 17, so that the liquid reservoir container 6a and the accumulator 6b The overall shape of the regulator can be lowered in the height direction to reduce the installation space, and the volumes of the liquid reservoir 6a and the accumulator 6b can be individually selected to the required values. It has the following advantages and is characterized by its ability to fully perform its original refrigerant amount adjustment function, making it a truly valuable air-conditioning/heating device as a device.

[Brief explanation of drawings]

FIG. 1 is a device circuit diagram according to an example of the air conditioner of the present invention, FIG. 2 is a structural diagram of the refrigerant amount regulator in FIG. 1, and FIG. 3 is a plan view of the refrigerant amount regulator,
4A to 4C are schematic structural diagrams of a refrigerant amount regulator according to each example of the air conditioner of the present invention, FIG. 5 is a device circuit diagram of the air conditioner for comparison with the air conditioner of the present invention, and
7 and 7 are schematic structural diagrams of each example of a heat exchange type refrigerant amount regulator used in the apparatus of FIG. 5. DESCRIPTION OF SYMBOLS 1... Outdoor unit, 2... Indoor unit, 3... Compressor, 4... Refrigerant heating coil, 5... Pressure reducer, 6... Refrigerant amount regulator, 6a... Liquid storage container, 6b... Accumulator, 7... Heating device, 8... Indoor coil, 17...
Partition torso.

Claims (1)

[Claims] 1 compressor 3, condenser, pressure reducer 5, heating device 7,
An outdoor unit 1 having a refrigerant heating coil disposed to be able to exchange heat with the heating device 7, an indoor unit 2 having an indoor coil 8 disposed at a higher location than the outdoor unit 1, and both units 1 and 2. The refrigerant circuit consists of two refrigerant pipes 11 and 12 that connect each other, and performs cooling operation and refrigerant heating using a compression refrigeration cycle that operates a compressor 3 to forcefully circulate refrigerant between the outdoor unit 1 and the indoor unit 2. This is an air conditioner/heater that performs heating operation by a natural circulation heating cycle in which a refrigerant heated by a heating device 7 is naturally circulated between a coil and an indoor coil 8, and the vertically-shaped body placed in contact with the outside air is used as a heating/air conditioner. The outdoor unit 1 is provided with a refrigerant amount regulator 6 formed into a double cylinder partitioned into an inner chamber and an outer chamber that can exchange heat between them by a thermal partition body 17, and the inner chamber is kept at low pressure during cooling operation. A heating and cooling system characterized in that the gas refrigerant is formed in an accumulator 6b through which vaporized refrigerant flows during heating operation, and the outer chamber is formed in a liquid storage container 6a through which low-pressure liquid refrigerant is stored during cooling operation and condensed liquid refrigerant is stored during heating operation. Machine.