JP3361144B2 - Multi-room air conditioner with mixed cooling and heating - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold / heat mixed multi-chamber air conditioner capable of protecting a compressor from oil shortage by reducing the outflow of oil from the compressor.

[0002]

2. Description of the Related Art In recent years, in a building air conditioner, an indoor unit is installed in each of a plurality of rooms having different loads, and a cooling / heating mixed multi-room air conditioner for connecting this to one outdoor unit is used for each room. Individual distributed air-conditioning for air conditioning is often used. Due to the length and complexity of the pipes, oil that has flowed out of the compressor is difficult to return, and oil separators are often used to prevent outflow. As a conventional oil separator, actual Kaihei 4-3
There is one disclosed in Japanese Patent No. 2465.

An example of the conventional cooling / heating mixed multi-room air conditioner will be described below with reference to FIGS. FIG. 5 is a refrigerant system diagram for cooling an outdoor unit of a conventional cooling / heating mixed multi-room air conditioner, and FIG. 6 is a refrigerant system diagram for simultaneously cooling and heating an indoor unit of a conventional cooling / heating mixed multi-room air conditioner. is there.

In the figure, 1 is a compressor, 2 is an oil separator provided on the downstream side of the compressor 1, 3 is a four-way valve provided on the downstream side of the oil separator 2, 4 is an outdoor heat exchanger, and When it functions as a container, it is located on the downstream side of the four-way valve 3. Reference numeral 5 is an outdoor blower that sends air to the outdoor heat exchanger 4, and 6 is a check valve connected to the indoor unit side end of the outdoor heat exchanger 4, which flows from the outdoor heat exchanger 4 to the indoor unit. Do not run in the opposite direction.

Reference numeral 7 is an outdoor expansion valve connected in parallel to the check valve 6, 8 is a liquid pipe connected to the check valve 6 and the outdoor expansion valve 7,
9 is a discharge gas pipe connected between the oil separator 2 and the four-way valve 3, 10 is a suction gas pipe, and 11 is a gas-liquid separator connected to the suction gas pipe 10.

12, 12 'are the liquid pipe 8 and the indoor heat exchanger 1
Indoor expansion valve connected to one end of 3, 13 ', 14, 1
4'is an indoor blower that sends air to the indoor heat exchangers 13 and 13 ', 15 and 16 are solenoid valves (open), 15' and 16 'are solenoid valves (close), and solenoid valves 15 and 15' are indoors. Heat exchanger 1
The other end of the solenoid valves 3 and 13 is connected to the suction gas pipe 10, and the solenoid valve 1
Reference numerals 6 and 16 ′ are connected to the other ends of the indoor heat exchangers 13 and 13 and the discharge gas pipe 9. An oil return capillary 17 is connected in parallel to the solenoid valves 16 and 16 '.

The operation of the conventional cooling / heating mixed multi-room type air conditioner configured as described above will be described below.

The high-temperature and high-pressure gas-state refrigerant compressed by the compressor 1 passes through the oil separator 2 and the four-way valve 3 and then flows into the outdoor heat exchanger 4, where the outdoor blower 5 causes the outdoor heat exchanger to flow. Heat is exchanged with the outside air passing through 4 to become a high-temperature high-pressure liquid-state refrigerant, which passes through the check valve 6 and is supplied to the liquid pipe 8.

In the indoor unit during cooling, the liquid pipe 8
The high-temperature high-pressure liquid-state refrigerant supplied from the indoor expansion valve 1
It is vaporized in 2 and flows into the indoor heat exchanger 13, and the indoor blower 14 exchanges heat with the air in the room passing through the indoor heat exchanger 13 to cool the room. After that, the refrigerant passes through the electromagnetic valve (open) 15, the suction gas pipe 10, the gas-liquid separator 11, and returns to the compressor 1. Since the solenoid valve (closed) 16 'is closed in the indoor unit during cooling, the discharge gas pipe 9
The oil accumulated inside is gradually returned from the oil return capillary 17 to the suction gas pipe 10.

At this time, if there is an indoor unit that is being heated at the same time, after the refrigerant in the high-temperature and high-pressure gas state branched off before the four-way valve 3 and supplied to the discharge gas pipe 9 passes through the solenoid valve (open) 16. , Heat is exchanged with the air in the room that flows into the indoor heat exchanger 13 ′ and passes through the indoor heat exchanger 13 ′ by the indoor blower 14 ′ to heat the room to become a liquid refrigerant, and the indoor expansion valve 12 ′ is turned on. After passing, it is supplied to the liquid pipe 8.

[0011]

However, in the above-mentioned conventional structure, even if the oil separator 2 is used, the outflow of oil cannot be completely prevented, so that all the indoor units are cooled at the end of the discharge gas pipe 9 during cooling. There is no solenoid valve such as the solenoid valve (open) 16 and the oil in the discharge gas pipe 9 is returned only by the amount passing through the oil return capillary 17.

Therefore, there is a drawback that the amount of oil returned is small and the compressor 1 runs out of oil, which adversely affects the compressor 1.

The present invention solves the above-mentioned conventional problems, and prevents the outflow of oil to the discharge gas pipe, prevents the compressor from running out of oil, and adversely affects the compressor even when all the indoor units are cooled. An object of the present invention is to provide a cooling / heating mixed room multi-room air conditioner that can comfortably air-condition without air conditioning.

[0014]

To achieve this object, a cooling / heating mixed multi-chamber air conditioner according to the present invention is provided with a discharge gas pipe extending from an outdoor unit and a pipe into which a discharge pipe of a compressor enters a four-way valve. And a strainer having an upward slope is provided on the discharge gas pipe side.

Further, from the branch point where the discharge pipe of the compressor branches into the pipe for entering the four-way valve and the discharge gas pipe extending from the outdoor unit, to the strainer having an upward slope provided on the discharge gas pipe side. The configuration is such that the distance to the slope start point is as short as possible for pipe processing.

Further, at the branch point where the discharge pipe of the compressor branches into a pipe that enters the four-way valve and a discharge gas pipe that extends from the outdoor unit, the discharge gas pipe side is up and the four-way valve inlet side is down. It has a branched structure.

[0017]

In the cooling / heating mixed multi-chamber air conditioner of the present invention, since the strainer is provided as described above, the oil in the refrigerant flowing out to the discharge gas pipe side after the branching is in the upslope portion of the strainer. The flow velocity is reduced, the flow is separated by the mesh in the strainer, flows backward along the downward gradient in the pipe to the branch point, and then flows into the pipe that enters the four-way valve. Therefore, the oil flows into the liquid pipe and returns to the compressor via the indoor unit that is being cooled. Therefore, the compressor can be prevented from running out of oil, and comfortable air conditioning can be performed without adversely affecting the compressor.

Further, since the distance from the branch point to the slope start point to the strainer is made as short as possible in terms of piping processing, the oil separated by the mesh in the strainer flows in the piping in a shorter time. Since it flows backward to the branch point and flows into the pipe side that enters the four-way valve, the oil circulates more efficiently, prevents the compressor from running out of oil, and allows comfortable air conditioning without adversely affecting the compressor.

Further, at the branch point, since the branch is branched so that the discharge gas pipe side is on the top and the four-way valve inlet side is on the bottom, the oil separated by the mesh in the strainer and flowing back to the branch point in the pipe is Since it flows into the pipe side that enters the four-way valve below without staying, the oil circulates more efficiently, prevents the compressor from running out of oil, and provides comfortable air conditioning without adversely affecting the compressor. it can.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a cooling / heating mixed multi-room air conditioner according to the present invention will be described below with reference to FIGS. It should be noted that the same configurations as those of the conventional one are denoted by the same reference numerals and detailed description thereof will be omitted.

FIG. 1 is a refrigerant system diagram of an outdoor unit of a first embodiment of a cooling / heating mixed multi-room type air conditioner according to the present invention during cooling, and FIG. 2 is a front view of essential parts showing a strainer mounting of the same embodiment. Is.

In the figure, reference numeral 18 denotes a discharge pipe of the compressor 1, and a pipe 19 which enters the four-way valve 13 and a discharge gas pipe 20 which extends from the outdoor unit are branched at a branch point 21 to form a discharge gas pipe 2
A strainer 22 having an upslope is provided on the 0 side.

The operation of the cooling / heating mixed multi-room air conditioner configured as described above will be described below.

Even if some of the oil in the high-temperature and high-pressure gaseous refrigerant compressed by the compressor 1 passes through the oil separator 2 and flows from the branch point 21 toward the discharge gas pipe 20, the strainer 22 The flow rate is reduced at the up-gradient portion of the strainer, separated by a mesh (not shown) in the strainer 22, and flows backward along the down-gradient through the discharge gas pipe 20 to the branch point 21 and enters the four-way valve 3 side of the pipe 19 Flow into.

Therefore, the oil flows into the liquid pipe 8 and passes through the indoor unit (not shown) that is being cooled, and then the compressor 1
Come back. Therefore, comfortable air conditioning can be performed without the oil being accumulated in the discharge gas pipe 9 and causing the compressor 1 to run out of oil and adversely affecting the compressor 1.

As described above, in the cooling / heating mixed multi-room air conditioner of this embodiment, the pipe 1 in which the discharge pipe 18 of the compressor enters the four-way valve 3
9 and a discharge gas pipe 20 extending from the outdoor unit, and a strainer 22 having an upward slope is provided on the discharge gas pipe 20 side, so that oil circulates efficiently and the compressor is Comfortable air conditioning can be performed without adversely affecting 1.

Next, a second embodiment of the cooling / heating mixed multi-room air conditioner according to the present invention will be described with reference to FIG. The same components as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 3 is a front view of the essential parts showing the attachment of the strainer of the second embodiment. In the figure, 21 is a branch point,
23 is the start point of the gradient to the strainer 22, and the branch point 2
The configuration is such that the distance between 1 and the slope start point 23 is as short as possible in terms of piping processing.

The operation of the cooling / heating mixed multi-room type air conditioner configured as described above will be described below.

The cooling / heating mixed multi-room air conditioner of this embodiment is
Due to the above configuration, the oil separated by the mesh (not shown) in the strainer 22 flows back to the branch point 21 in a shorter time and flows into the pipe 19 side entering the four-way valve 3, so that the efficiency is further improved. The oil circulates well and prevents the compressor (not shown) from running out of oil, and the compressor (not shown)
Comfortable air conditioning without adversely affecting

As described above, the cooling / heating mixed multi-chamber air conditioner of this embodiment has a configuration in which the distance from the slope start point 23 to the strainer 22 to the branch point 21 is as short as possible in terms of piping processing. The oil circulates more efficiently, and comfortable air conditioning can be performed without adversely affecting the compressor (not shown).

Next, a third embodiment of the cooling / heating mixed multi-room air conditioner according to the present invention will be described with reference to FIG. The same components as those in the second embodiment are designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 4 is a front view of an essential part showing a branched portion of the third embodiment. In the figure, at a branch point 21 where a discharge pipe 18 of a compressor branches into a pipe 19 that enters the four-way valve 3 and a discharge gas pipe 20 that extends from an outdoor unit, enter the four-way valve 3 with the discharge gas pipe 20 side upward. It has a structure in which the pipe 19 side is branched downward.

The operation of the cooling / heating mixed multi-room air conditioner configured as described above will be described below.

The cooling / heating mixed multi-room air conditioner of this embodiment is
Due to the above configuration, the oil separated by the mesh (not shown) in the strainer 22 is
Since it flows backward to the pipe 19 side that enters the four-way valve 3 on the lower side without staying, the oil circulates more efficiently and prevents the compressor (not shown) from running out of oil and prevents the compressor (not shown). The comfortable air conditioning can be performed without adversely affecting

As described above, the cooling / heating mixed multi-room type air conditioner of this embodiment is provided with the strainer 22 at the branch point 21 and in the middle thereof.
Since the discharge gas pipe 20 extending from the outdoor unit having the above is branched and the pipe 19 side entering the four-way valve 3 is branched downward, the oil circulates more efficiently and is compressed. Comfortable air conditioning can be performed without adversely affecting the machine (not shown).

[0037]

As described above, as is apparent from the embodiments, the cooling / heating mixed multi-chamber air conditioner of the present invention has a discharge pipe of a compressor as a pipe into a four-way valve and a discharge gas pipe extending from an outdoor unit. Since it is branched and has a strainer with an upward slope on the discharge gas pipe side, even when all indoor units are cooled, oil is prevented from flowing out to the discharge gas pipe and the compressor runs out of oil. The air conditioning can be performed comfortably without adversely affecting the compressor.

Further, from the branch point where the discharge pipe of the compressor branches into the pipe for entering the four-way valve and the discharge gas pipe extending from the outdoor unit, to the strainer having an upward slope provided on the discharge gas pipe side. Since the distance to the gradient start point is made as short as possible in terms of piping processing, even when all indoor units are being cooled, it is possible to prevent oil from flowing out to the discharge gas pipe more efficiently and prevent the compressor from running out of oil. Prevents and can comfortably air-condition without adversely affecting the compressor.

Also, at the branch point where the discharge pipe of the compressor branches into a pipe that enters the four-way valve and a discharge gas pipe that extends from the outdoor unit, the discharge gas pipe side is on the top and the four-way valve inlet side is on the bottom. Since it has a branched structure like this, even when all indoor units are cooled, it is possible to prevent oil from flowing out to the discharge gas pipe more efficiently and prevent the compressor from running out of oil.
Comfortable air conditioning is possible without adversely affecting the compressor.

[Brief description of drawings]

FIG. 1 is a first multi-chamber air conditioner with cooling and heating according to the present invention.
Refrigerant system diagram when cooling the outdoor unit of the embodiment

FIG. 2 is a front view of a main portion showing a mounted state of the strainer of the same embodiment.

FIG. 3 is a second view of the multi-room air conditioner with mixed cooling and heating according to the present invention.
Front view of essential parts showing the mounted state of the strainer of the embodiment

FIG. 4 is a third view of a multi-room air conditioner with mixed cooling and heating according to the present invention.
Front view of essential parts showing the branching method of the embodiment

FIG. 5: Refrigerant system diagram during cooling of an outdoor unit of a conventional cooling / heating mixed multi-room air conditioner

FIG. 6 is a refrigerant system diagram for simultaneous cooling and heating of an indoor unit of a conventional cooling / heating multi-room air conditioner.

[Explanation of symbols]

1 compressor 3 four-way valve 4 outdoor heat exchanger 8 liquid tubes 9 Discharge gas pipe 10 Inhalation gas pipe 13,13 'Indoor heat exchanger 18 Compressor discharge pipe 19 Piping that goes into the four-way valve 20 Discharge gas pipe extending from the outdoor unit 21 fork 22 Strainer 23 slope start point

Claims (3)

(57) [Claims] 1. A liquid pipe, a discharge gas pipe, and a suction gas pipe are provided between one outdoor unit having a compressor, a four-way valve, and an outdoor heat exchanger, and between a plurality of indoor units each having an indoor heat exchanger. A cooling / heating mixed multi-chamber air conditioner connected by three pipes, wherein a discharge pipe of the compressor is branched into a pipe entering the four-way valve and a discharge gas pipe extending from the outdoor unit, A cool / heat mixed multi-room air conditioner comprising a strainer having an upward slope on the discharge gas pipe side and having a mesh inside. 2. The distance from the branch point where the discharge pipe of the compressor branches into a pipe that enters the four-way valve and the discharge gas pipe that extends from the outdoor unit to the start point of the gradient to the strainer is as short as possible in terms of piping processing. The multi-room air conditioner of mixed cooling and heating according to claim 1. 3. A discharge pipe of a compressor branches at a branch point into a pipe for entering a four-way valve and a discharge gas pipe extending from an outdoor unit, with the discharge gas pipe side up and the four-way valve inlet side down. The multi-room air conditioner with mixed cooling and heating according to claim 1 or claim 2, which is branched.