JP2003279176A - Air conditioning device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioning device combining a high pressure vessel type and a low pressure vessel type compressor and balancing oil levels of each compressor without detecting oil levels. <P>SOLUTION: The high pressure vessel type compressor 10 and the low pressure vessel type compressor 11 are combined, a first oil leveling pipe 38 provided with a flow passage resistance 37 is provided to connect a vessel position A of necessary and sufficient oil quantity stored in the compressor 10 and a vessel of the compressor 11, and a second oil leveling pipe 39 is provided to connect a vessel position B of necessary and sufficient oil quantity stored in the compressor 11 and a suction pipe 35a of the compressor 10. Consequently, if the oil returns to one of the compressors, excessive oil stored in each the compressor is supplied to another compressor via the first oil leveling pipe 38 or the second oil leveling pipe 39 to balance quantity of oil stored in both of the compressors without providing an oil level sensor. <P>COPYRIGHT: (C)2004,JPO

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 plurality of compressors for oil balance.

[0002]

2. Description of the Related Art Generally, in an air conditioner, a compressor, an outdoor unit containing an outdoor heat exchanger, an indoor unit containing an indoor heat exchanger, a liquid pipe and a gas pipe are provided. Connected with a refrigerant pipe, the refrigerant compressed by the compressor,
In the cooling operation, heat is radiated and condensed in the outdoor heat exchanger, the condensed refrigerant is allowed to absorb heat in the indoor heat exchanger, and evaporated to perform the operation. In the heating operation, the indoor heat exchanger is used. The heat is dissipated and condensed, and the condensed refrigerant is absorbed by the outdoor heat exchanger and evaporated to operate.

For example, in an air conditioner whose operating capacity is relatively large and variable, the compressor incorporated in the outdoor unit is divided into a plurality of compressors instead of one compressor.
It consisted of a variable capacity compressor and a constant speed compressor connected in parallel.

Here, in the electric compressor, a compressor for compressing a refrigerant and an electric motor for driving the compressor are housed in a container of the compressor, and a discharge pipe and a suction pipe are provided. A high pressure container type and a low pressure container type are distinguished depending on whether the discharge pipe or the suction pipe is connected to the compression unit built in the compressor. It had been.

When constructing an outdoor unit containing a plurality of compressors, if all the compressors are high-pressure container type or low-pressure container type compressors, the pressure in each compressor is the same. Because of the pressure, by connecting the containers of each compressor with an oil equalizing pipe, even if the oil returns to one of the plurality of compressors, the oil is exchanged through this oil equalizing pipe. By doing so, it was possible to balance the oil levels of the compressors.

On the other hand, when the high-pressure container type compressor and the low-pressure container type compressor are combined, the pressures in the respective compressors are different. Therefore, as described above, an oil equalizing pipe is provided to balance the oil balance. Since it cannot be performed, both the high-pressure container type compressor and the low-pressure container type compressor are provided with oil level sensors, and from the oil separator, the oil return valve to each compressor, By providing an oil return pipe having a flow path resistor, detecting the oil level of each compressor, and opening the oil return valve of the compressor determined to have a low oil level, While replenishing the oil held in the compressor, it also balanced the oil.

[0007]

However, according to the method of detecting the oil level, replenishing the oil, and balancing the oil, the discharge pipe and the suction pipe are branched and connected in parallel. It is necessary to provide the oil level sensor and the oil return pipe from the oil separator to all the compressors to be operated, and further to drive the oil level detection unit from the oil level sensor and the oil return valve. Since a drive circuit section is required, the cost is inevitably increased by this amount.

Therefore, an object of the present invention is to provide a high-pressure container type,
An object of the present invention is to provide an air conditioner that combines a compressor with a low-pressure container type tube to balance the oil level of each compressor without detecting the oil level.

[0009]

According to a first aspect of the present invention, there is provided an air conditioner in which a high pressure container compressor and a low pressure container compressor are connected in parallel, and a container of the high pressure container compressor is provided. , A container of the low-pressure container compressor is connected by a first refrigerant pipe provided with a flow path resistor, and a container of the low-pressure container compressor and a suction pipe of the high-pressure container compressor are connected to a second It is characterized by being connected by a refrigerant pipe.

According to a second aspect of the present invention, in the first aspect, the height position at which the first refrigerant pipe is connected to the container of the high pressure container compressor is required to be sufficient for the high pressure container compressor. And a height position where the second refrigerant pipe is connected to the container of the low-pressure container compressor is set to a position where a minimum oil amount of the low-pressure container compressor can be ensured. It is a thing.

According to a third aspect of the present invention, in the first aspect, the height position at which the first refrigerant pipe is connected to the container of the high pressure container compressor is required to be sufficient for the high pressure container compressor. A position where a sufficient amount of oil can be secured, and a height position where the second refrigerant pipe is connected to the container of the low pressure container compressor is a position where a necessary and sufficient amount of oil of the low pressure container compressor can be secured. It is what

The invention according to a fourth aspect is the first to the third aspects.
In any one of the above, the position of connecting the second refrigerant pipe to the suction pipe of the high-pressure container compressor is higher than the position of the container of the low-pressure container compressor connecting the second refrigerant pipe. It is characterized by having a low position.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is an air conditioner in which a high-pressure container type compressor according to the present invention and a low-pressure container type compressor are combined and an oil balance between both compressors is possible without using an oil level sensor. It is the schematic which showed about.

First, the outdoor unit 1 includes a compressor 10
, Compressor 11, oil separator 31, and four-way valve 1
2, an outdoor heat exchanger 13, an outdoor motor-operated valve 14, and an accumulator 15 are connected to each other by a refrigerant pipe and incorporated therein, and further, an outdoor blower 16 that blows air to the outdoor heat exchanger 12 and the outdoor fan 16. The outdoor control unit 17 that controls the unit 1 and communicates with the indoor control unit 23 built in the indoor unit 2 is built in.

The indoor unit 2 includes an indoor motor operated valve 2
0 and the indoor heat exchanger 21 are connected by a refrigerant pipe to be built in, and an indoor blower 22 that blows air to the indoor heat exchanger 21, a control of the indoor unit 2, and a built-in outdoor unit 1. The indoor control unit 23 that communicates with the outdoor control unit 17 is built in.

The outdoor unit 1 and the indoor unit 2 are connected by the inter-unit piping 3 and the communication wiring 4 to form the air conditioner 100, and the indoor unit 2
An operation signal from the indoor control unit 23 incorporated in the outdoor control unit 17 controls the operation of the compressors 10 and 11 and the like, and the operation is started.
In the cooling operation, the refrigerant discharged from 11 flows through the oil separator 31, passes through the four-way valve 12, receives the air blow from the outdoor blower 16 in the outdoor heat exchanger 13, radiates heat, and is condensed. The pressure is reduced by the outdoor electric valve 14, flows into the indoor unit 2 via the liquid pipe 3a of the inter-unit pipe 3, and passes through the indoor electric valve 20 to blow air from the indoor blower 22 by the indoor heat exchanger 21. Upon receiving, absorbing heat and evaporating, returning to the outdoor unit 1 via the gas pipe 3b of the inter-unit pipe 3, and passing through the accumulator 15 to the compressor 1
The air is circulated in the circulation path returning to 0 and 11, and the air conditioning operation for cooling is performed.

The high pressure container type compressor 10
The configuration of the low-pressure container type compressor 11 will be described in detail. Referring to FIG. 2, on the discharge side of the compressor, the discharge pipe 30c extending from the discharge port of the compressor 11 has a check valve 32. Via the discharge pipe 30b, which is connected to the discharge pipe 30a extending from the discharge port of the compressor 10, and as the discharge pipe 30 to the oil separator 31.
A refrigerant pipe directed to the condenser side and an oil return pipe 34 having a flow path resistor 33 are connected to the No. 1.

Explaining the suction side of the compressor, a small accumulator 36 is provided near the suction port of the compressor 10. This small accumulator 36 is provided.
The suction pipe 35a extends through the suction pipe 35b and is connected to the suction pipe 35b extending from the compressor 11, and is connected to the accumulator 15 as the suction pipe 35. The accumulator 15 is connected to a refrigerant pipe toward the evaporator side. ing.

Further, a first oil leveling pipe 38 having a flow path resistor 37 has one end thereof at a position A of the container of the compressor 10,
The other end is provided by being connected to the container of the compressor 11,
The oil equalizing pipe 39 has one end at a position B of the container of the compressor 11.
The other end is connected to the position C of the suction pipe 35a of the compressor 10.

The position A of the container of the compressor 10 to which the first oil equalizing pipe 38 is connected is set at a height position where a necessary and sufficient amount of oil held in the compressor 10 can be secured. , The compressor 1 to which the second oil equalizing pipe 39 is connected
The position B of the first container is a height position where a necessary and sufficient amount of oil held in the compressor 11 can be secured.
The position C of the other end of the oil equalizing pipe 39 is located in the vicinity of the small accumulator 36 on the suction pipe 35a, and the suction pipes 35a, 35
It is located at a position distant from the place where b is branched, and is located lower than the position B of the container of the compressor 11 in the height direction.

This is because the high pressure container type compressor 10 and the low pressure container type compressor 11 are connected by a first oil equalizing pipe 38 and decompressed by a flow path resistor 37. Since a high pressure is applied to the compressor 11, this compressor 1
Although the pressure inside the container 1 is slightly higher than that of the suction pipe 35a, even if this slight pressure difference is canceled by the pressure loss of the second oil equalizing pipe 39, to the suction pipe 35a, The oil stored in the compressor 11 is
This is because, when the position is equal to or higher than the position B of the container of the compressor 11, the surplus amount of oil held in the compressor 11 is easily discharged due to the weight of the oil.

When the compressors 10 and 11 start operating, the refrigerant containing oil is compressed in each of the compressors 10 and 11 to become high temperature and high pressure, and the discharge pipe 3
0a, 30b, merges in the discharge pipe 30, and flows into the oil separator 31.
At 1, a part of the oil is separated from the refrigerant containing the oil and gradually returned to the suction pipe 35 through the oil return pipe 34 having the flow path resistor 33.

The oil returned while circulating in the indoor unit 2 while being contained in the refrigerant flows through the suction pipe 35 via the accumulator 15 and is returned by the oil return pipe 34. And suction pipe 35a
And 35b, and returned to the compressors 10 and 11.

At this time, the oils returned to the respective compressors 10 and 11 change every moment depending on the operating states of the respective compressors 10 and 11. Therefore, how much oil flows into which compressor. It is unknown whether it is.

Here, when the oil flows into the compressor 10, the amount of oil held in the compressor 10 naturally increases, but at the position where the first oil equalizing pipe 38 is connected. If it exceeds A, each compressor 10, 11
Due to the pressure difference in the container, the surplus oil amount retained in the compressor 10 is supplied to the compressor 11 through the first oil equalizing pipe 38, and the oil amount retained in the compressor 11 is reduced. It is possible to increase it.

On the other hand, when the oil flows into the compressor 11, naturally, the amount of oil held in the compressor 11 increases, but as described above, the compressor 11 has a large amount of oil. A first oil leveling pipe 38 is connected to the compressor 11
Due to the fact that the internal pressure is slightly higher than the internal pressure of the suction pipe 35a and the height difference in the height direction between the position B of the container of the compressor 11 and the position C on the suction pipe 35a, The amount of oil held in 11 is equal to the second oil leveling pipe 3
9 exceeds the connected position B, the surplus amount of oil retained in the compressor 11 is supplied to the position C on the suction pipe 35a connected to the compressor 10 and compressed. It is possible to increase the amount of oil that is collected in the compressor 10 and stored in the compressor 10.

As described above, the oil equalizing pipe is provided at a position where the necessary and sufficient oil amount of each compressor can be secured, and the surplus amount of the necessary and sufficient oil amount is supplied to the other compressor or the suction pipe. By supplying the oil, it becomes possible to balance the amount of oil held in each compressor.

In the description so far, the first oil equalizing pipe 38 is the high pressure container type compressor 10 as described above.
And a low-pressure container type compressor 11 are connected to each other, a sufficient high and low pressure difference is applied, and the oil supply through the first oil leveling pipe 38 is smoothly performed. A is a position where a necessary and sufficient amount of oil of the compressor 10 can be secured, but regarding the second oil equalizing pipe 39,
It is provided by connecting the container of the low-pressure container type compressor 11 and the suction pipe 35 that has a low pressure, and the internal pressure of the compressor 11 can be said to be slightly increased by the first oil equalizing pipe 38. Since the pressure in the flow path resistor 37 is close to the suction pipe 35 side, the oil retained in the compressor 11 does not suddenly flow out to the suction pipe 35. The position B of the container of the compressor 11 is the compressor 1
It is also possible to set the position so as to secure the minimum amount of oil required in 1.

Further, in the present embodiment, the high-pressure container type compressor and the low-pressure container type compressor are connected one by one, respectively, but described as a configuration of two compressors. In particular, it is not necessary to limit the number of compressors to two, and even when a plurality of compressors such as three and four are combined, the container of the low-pressure container type compressor is more than the container of the high-pressure container type compressor. What,
By providing the first oil equalizing pipe and providing the second oil equalizing pipe from the container of the low-pressure container type compressor to the suction pipe of the high-pressure container type compressor, oil balance can be achieved without using an oil level sensor. It is possible.

[0031]

From the above description, the high-pressure container type compressor container and the low-pressure container type compressor container are connected by the first oil leveling pipe, and the first oil leveling pipe is connected. The container position of the mold compressor is set to a position where a necessary and sufficient amount of oil can be secured, and the container of the low-pressure container compressor and the suction pipe of the high-pressure container compressor are formed by the second oil equalizing pipe. By connecting, the container position of the low-pressure container type compressor at one end connecting the second oil equalizing pipe is set to a position where a necessary and sufficient amount of oil can be secured or a position where a minimum amount of oil can be secured,
By providing the position at the other end to the suction pipe at a position lower in the height direction than the container position of the low-pressure container type compressor, even if all the oil returns to one compressor, Since the surplus oil is supplied to the other compressor through the first oil equalizing pipe and the second oil equalizing pipe, the oil level of each compressor is balanced without detecting the oil level. It becomes possible.

[Brief description of drawings]

FIG. 1 is a refrigerant circuit diagram showing an embodiment of an air conditioner according to the present invention.

FIG. 2 is a refrigerant circuit diagram in which the features of the air conditioner according to the present invention are extracted and shown.

[Explanation of symbols]

10 Compressor (high pressure container type) 11 Compressor (low pressure container type) 15 Accumulator 30 discharge pipe 31 Oil separator 32 Check valve 33 flow path resistor 34 Oil return pipe 35 Suction tube 36 Small Accumulator 37 flow path resistor 38 1st oil level pipe 39 Second oil level pipe 100 air conditioner A Required and sufficient oil level position for high-pressure container compressor B Oil level position of low pressure container compressor C Second oil level pipe connection position

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazutoyo Kagami             1 Otsuki-cho, Ashikaga City, Tochigi Prefecture Sanyo Electric Air Conditioning             Within the corporation

Claims (4)

[Claims] 1. An air conditioner comprising a high-pressure container compressor and a low-pressure container compressor connected in parallel, wherein a flow path is provided between the container of the high-pressure container compressor and the container of the low-pressure container compressor. An air conditioner characterized by being connected by a first refrigerant pipe provided with a resistor, and further by connecting a container of the low-pressure container compressor and a suction pipe of the high-pressure container compressor by a second refrigerant pipe. . 2. The height position where the first refrigerant pipe is connected to the container of the high pressure container compressor is set to a position where a necessary and sufficient amount of oil of the high pressure container compressor can be secured, and the second refrigerant pipe is The air conditioner according to claim 1, wherein a height position where the low-pressure container compressor is connected to a container is set to a position where a minimum oil amount of the low-pressure container compressor can be secured. 3. The height position where the first refrigerant pipe is connected to the container of the high-pressure container compressor is a position where a necessary and sufficient amount of oil of the high-pressure container compressor can be secured, and the second refrigerant pipe is The air conditioner according to claim 1, wherein a height position where the low-pressure container compressor is connected to a container is set to a position where a necessary and sufficient amount of oil of the low-pressure container compressor can be secured. 4. A position where the second refrigerant pipe is connected to a suction pipe of the high-pressure container compressor is lower than a position of the container of the low-pressure container compressor where the second refrigerant pipe is connected in a height direction. The air conditioner according to any one of claims 1 to 3, characterized in that.