JP2003042603A - Refrigerating cycle apparatus, method for manufacturing the same and method for operating the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that when already using refrigerant is mixed with a refrigerating machine oil before a new refrigerant machine oil is retained in an existing duct after the refrigerant is replaced with another new refrigerant, if a concentration of the new oil is low, reliability of a refrigerating cycle apparatus is lowered. SOLUTION: After a heat source machine which operates by using the new refrigerant is replaced, the refrigerating machine oil corresponding to the new refrigerant flows into the duct at a vacuum evacuation time until the concentration of the existing oil becomes a predetermined value or less.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration cycle apparatus and a refrigeration cycle apparatus manufactured by replacing a heat source machine using a first refrigerant and refrigerating machine oil with a heat source machine used for a different refrigerant and refrigerating machine oil. It relates to a driving method and a driving method.

[0002]

2. Description of the Related Art Conventionally, in a refrigeration cycle apparatus, an HCFC or CFC refrigerant is used as a refrigerant, and a mineral oil is used as a refrigerating machine oil. However, HCFC-based and CFC-based refrigerants have a problem that they destroy the ozone layer.
Replacement of a refrigeration cycle device for a CFC-based refrigerant with a refrigeration cycle device for an HFC-based refrigerant that does not destroy the ozone layer is now frequently performed.

However, in the case of a refrigeration cycle apparatus in which a connecting pipe connecting an outdoor unit and an indoor unit is buried in a wall, it is difficult to newly bury the connecting pipe, so that the outdoor unit is not used. Only indoor units are being changed to HFC refrigerants. Refrigerating machine oil for HCFC / CFC refrigerants is mineral oil, whereas refrigerating machine oil for HFC refrigerants is ester oil etc. There is a need to address the problem of compressor unreliability caused by the mineral oil adhering to the connecting pipes.

An example of such a coping method is Japanese Patent Laid-Open No.
No. 00-9368 and JP 2000-14636.
There is one disclosed in Japanese Patent No.

In Japanese Patent Laid-Open No. 2000-9368, ester oil carried out from a compressor is completely separated by a high-performance oil separator, and foreign matter such as mineral oil flowing with a refrigerant is provided in a gas line. A method of capturing and separating with a collector is disclosed. However, this method requires an expensive oil separator capable of completely separating the ester oil taken out from the compressor, and further, the ester oil flows out from the oil separator without being separated by the oil separator. In such a case, the ester oil that has flowed out is captured by the foreign matter capture device, so that there is a problem that the amount of refrigerating machine oil in the compressor decreases and there is a possibility of poor lubrication.

Further, in Japanese Unexamined Patent Publication No. 2000-146369, the inside of the oil separator provided in the liquid line is partitioned, and the positions of the end portion of the inflow pipe and the end portion of the outflow pipe of the oil separator are made different from each other. A method of storing oil in an oil separator is disclosed. However, in this method, since the mineral oil located downstream of the oil separator once flows into the compressor, there is a problem in that the reliability of the compressor decreases if the proportion of this mineral oil is large.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. The first refrigerant,
For example, in a refrigeration cycle apparatus or a refrigeration / air-conditioning apparatus in which an HCFC-based / CFC-based refrigerant and a first refrigerating machine oil, such as mineral oil, are used, a second refrigerant, such as an HFC-based refrigerant and a second refrigerating machine oil, such as ester oil Even if the oil is replaced with ether oil or the like, and the replaced second ester oil, which is the second refrigerating machine oil, is mixed with the mineral oil, which is the first refrigerating machine oil that remains in the existing pipe, it occupies the entire refrigerating machine oil. It is an object of the present invention to provide a refrigeration cycle device capable of ensuring a certain concentration of the second refrigerating machine oil or more and further separating and recovering the mineral oil remaining in the existing pipe.

[0008]

In the method for manufacturing a refrigeration cycle apparatus according to the present invention, the first step of removing the first heat source device from the pipe and connecting the second heat source device to the pipe,
A second flow of the second refrigerating machine oil in the pipe until the ratio of the first refrigerating machine oil and the second refrigerating machine oil held in the accumulator of the second heat source machine reaches a predetermined value while evacuating;
And the process of.

Further, in the method for manufacturing a refrigeration cycle apparatus according to the present invention, a step of removing the first heat source device from the pipe and connecting the second heat source device in which the accumulator is filled with a predetermined amount of the second refrigerating machine oil to the pipe is provided. To have.

Further, the accumulator is inserted from the upper part of the container and the U-shaped pipe having an oil return hole for sending the refrigerant gas to the compressor, and is inserted from the upper part of the container to discharge the refrigerant gas into the container. The inlet pipe, and a weir that divides the inside of the container into a first chamber in which the U-shaped pipe is arranged and a second chamber in which the inlet pipe is arranged, except for a predetermined upper space, A predetermined amount of refrigerating machine oil was filled in the second chamber.

Further, the accumulator has a container, a U-shaped pipe which is inserted from the upper part of the container and sends the refrigerant gas to the compressor, and an inlet pipe which is inserted from the lower part of the container and discharges the refrigerant gas into the container. The oil return hole formed in the U-shaped pipe is arranged to be higher than the suction hole formed in the inlet pipe and lower than the tip opening portion of the inlet pipe.

Further, in the method for manufacturing a refrigeration cycle apparatus according to the present invention, the first heat source unit is removed from the pipe, and the second heat source unit in which the oil separator has been filled with a predetermined amount of the second refrigerating machine oil is connected to the pipe. It has a process.

Further, in the refrigeration cycle apparatus of the present invention, the first solenoid valve provided between the indoor heat exchanger and the accumulator and the first solenoid valve formed by branching the upstream side of the first solenoid valve are formed. A branch pipe, a second branch pipe formed by branching the downstream side of the first solenoid valve, an oil recovery device connected to the first branch pipe and the second branch pipe, and a first branch pipe. When the second solenoid valve provided in the branch pipe, the oil storage tank for storing the refrigerating machine oil, and the refrigerating machine oil of the compressor are below a predetermined amount,
A supply means for supplying refrigerating machine oil from the oil storage tank to the compressor is provided.

Further, the supply means includes an oil level detection means for detecting the oil level of the refrigerating machine oil, a pipe connecting the oil storage tank and the compressor, a solenoid valve provided in the pipe, and an oil level detection means. Control means for controlling the opening / closing of the solenoid valve based on the detected information is provided.

Further, a pressure equalizing pipe for connecting the oil storage tank and a pipe located upstream of the first electromagnetic valve, and pressure control means provided in the pressure equalizing pipe are provided.

Further, in the refrigeration cycle apparatus according to the present invention, the first solenoid valve provided between the indoor heat exchanger and the accumulator and the first solenoid valve formed by branching the upstream side of the first solenoid valve are formed. A branch pipe, a second branch pipe formed by branching the downstream side of the second solenoid valve, and an oil recovery device connected to the first branch pipe and the second branch pipe. did.

Further, there is provided a heating means for heating the liquid in the oil recovery device, and an arithmetic device for controlling the heating means based on the temperature and pressure of the second branch pipe.

Further, in the method for operating the refrigeration cycle apparatus according to the present invention, the first step of performing the pump down operation by closing the third solenoid valve, and the state in which the compressor is stopped,
A second step of opening the second solenoid valve and the third solenoid valve and closing the first solenoid valve, and after a lapse of a predetermined time, opening the first solenoid valve and opening the second solenoid valve. And a third step of closing.

Further, in the method for operating the refrigeration cycle apparatus according to the present invention, the first step of heating the indoor heat exchanger with the compressor stopped, and after the temperature-sensitive expansion valve detects a predetermined temperature , A second step of closing the first solenoid valve, opening the second solenoid valve, and starting the compressor.

Further, the oil recovery device has a heater for heating the liquid stored therein.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. 1 is a refrigerant circuit diagram showing a refrigeration cycle device according to Embodiment 1 of the present invention. In FIG. 1, the refrigeration cycle apparatus includes a compressor 1,
The oil separator 2, the heat source side heat exchanger 3, the expansion valve 4, the indoor side heat exchanger 5, and the accumulator 6 are mainly connected in this order. In addition, the lower part of the oil separator 2,
A pipe connecting the accumulator 6 and the compressor 1 is connected via an oil return capillary tube 7. Further, a port 8 is installed in the refrigerant gas discharge pipe of the oil separator 2. In addition, the compressor 1, the oil separator 2, the heat source side heat exchanger 3,
The accumulator 6, the oil return capillary tube 7 and the port 8 are arranged in the heat source unit 100 which is an outdoor unit, and the expansion valve 4 and the indoor heat exchanger 5 are arranged in the indoor unit 200 which is a user side. However, in a normal refrigeration cycle apparatus, a four-way valve is added to switch between cooling operation and heating operation, but it is omitted in FIG. 1 for simplification of description.

In such a refrigeration cycle apparatus, when it is attempted to change the existing refrigerant to a new refrigerant, the heat source machine using the existing first refrigerant and the first refrigerating machine oil is replaced with a new one of a different type. The heat source unit using the second refrigerant and the second refrigerating machine oil is replaced, and the existing pipe is not replaced. In this case, since the first refrigerating machine oil adheres to the existing pipe, the reliability of the compressor cannot be ensured unless the ratio of the second refrigerating machine oil to the entire refrigerating machine oil is secured to some extent or more. .

Therefore, it is necessary to adjust the amount of the second refrigerating machine oil in the entire refrigerating cycle, and the method will be described with reference to the flowchart of FIG. First, the heat source machine that used R22 as the first refrigerant and hard alkylbenzene oil (hereinafter, referred to as "HAB oil") as the first refrigerating machine oil was removed from the pipe, and R404 was used as the second refrigerant.
A, the heat source machine, which used the ester oil as the second refrigerating machine oil, is connected to the pipe to replace the heat source machine (step (hereinafter referred to as "S") 1).

Next, after the piping connection between the heat source unit 100 and the indoor unit 200 is completed, while a predetermined amount of ester oil is additionally filled from the port 8, evacuation is performed until a specified vacuum degree is reached (S2). Note that the ester oil flows through the heat source side heat exchanger 3, the expansion valve 4, and the indoor side heat exchanger 5 by additionally filling the ester oil into the refrigeration cycle while evacuating, and each device and the existing HAB remaining in the pipe
While mixing with oil, it flows into the accumulator 6,
Retained. The amount of ester oil to be additionally filled must be such that the proportion of HAB oil in the total oil retained in the accumulator 6 is at least 10% or less.

The amount of ester oil required for the entire refrigeration cycle apparatus to operate normally depends on the capacity (refrigeration capacity) of the refrigeration cycle apparatus, but is approximately 71 per 1 kW.
CC or more, for example, if the refrigerating capacity is 28 kW,
The total amount of ester oil in the refrigeration cycle needs to be about 2000 CC. Therefore, the total amount of the ester oil added during the evacuation and the amount of ester oil placed in the refrigerating apparatus immediately after the replacement is 2000 CC or more.

After the evacuation is completed, the refrigeration cycle apparatus is normally started (S3). When the refrigeration cycle device operates, the refrigerating machine oil held in the accumulator 6 is fed into the compressor 1, but the proportion of HAB oil in the refrigerating machine oil to be fed is at least 10% or less, and the proportion of ester oil is to some extent. Since the above is ensured, the reliability of the compressor 1 is not deteriorated and the conventional performance can be satisfied.

Here, although the ester oil was additionally filled in the refrigerating cycle apparatus together with evacuation, the heat source unit 10
Ester oil may be additionally filled into the refrigeration cycle apparatus at the same time as the exchange of 0, and then vacuuming may be performed. Also,
Even if the heat source device uses an HCFC-based refrigerant other than R22 or a CFC-based refrigerant as the first refrigerant, it can be used as a second refrigerating machine oil such as an HFC-based refrigerant or HC-based refrigerant other than R404A as the second refrigerant. There is no difference in the method of FIG. 2 even with a heat source device using an ether type or the like.

Embodiment 2. FIG. 3 is a refrigerant circuit diagram showing a refrigeration cycle device according to Embodiment 2 of the present invention, in which the structure of the accumulator in the refrigeration cycle device of FIG. 1 is changed. In FIG. 3, 9 is an accumulator, which is inside the heat source unit 100 and is connected to the downstream side of the indoor heat exchanger 5 of the indoor unit 200 by an existing pipe. As described above, in the case of changing from the existing refrigerant to the new refrigerant, first, the heat source device using the existing first refrigerant and the first refrigerating machine oil is replaced with the new second refrigerant of a different type. The heat source machine using the second refrigerating machine oil is replaced, and the state of the accumulator 9 immediately after this replacement will be described based on the vertical cross-sectional view of FIG.

In FIG. 4, an accumulator 9 includes a refrigerant inlet pipe 9a connected to the indoor heat exchanger 5 by a pipe, and a compressor 1.
And a U-shaped tube 9c having an oil return hole 9b of about several millimeters in the curved portion. The distance between the oil return hole 9b and the bottom surface of the accumulator 9 is h, and the ester oil 9d is filled up to this height h. The amount of the ester oil 9d pre-filled must be 99 times the amount of the HAB oil remaining inside the pipe, and the height h
Is determined.

For example, as shown in FIG. 5, when the accumulator 9 has a cylindrical shape with an inner radius of r (m) and a total length of Lacc (m), the height of the oil return hole is h (mm), The angle between the line extending directly below the center axis of the cylinder and the line between the center axis, the wall surface inside the cylinder, and the surface of the ester oil 9d is θ (r
ad), the refrigerating machine oil Voil accumulated in the accumulator 9 is expressed by the following equation.

[0031]

Therefore, the height h (mm) should be designed from Voil.

When the refrigeration cycle apparatus is operated in such a state, H remaining in the indoor unit 200 and existing pipes
The AB oil flows in the refrigeration cycle apparatus due to the shearing force of the refrigerant and flows into the accumulator 9, so that the concentration of the ester oil in the accumulator 9 decreases, but since it is secured in advance to some extent, it is possible to maintain the concentration above a certain level. . As a result, the amount of refrigerating machine oil in the accumulator 9 becomes larger than a predetermined holding amount (when it is higher than the oil return hole), and the refrigerating machine oil is sucked from the oil return hole 9b and sent to the compressor 1 even if it is frozen. Since the ester oil concentration of the machine oil can be secured to some extent, the reliability of the compressor 1 can be secured,
It is possible to maintain the same performance as the conventional one.

Embodiment 3. 6 is a vertical sectional view of an accumulator according to Embodiment 3 of the present invention.
In the above accumulator, a weir divides the accumulator into two chambers while leaving the upper connecting space. In FIG. 6, 10a is a weir, and the first room 10b and the second room 10 are left with the connecting space located at the upper part left.
Partitioned into c. A refrigerant inlet pipe 10d projects from the upper portion of the first chamber 10b, and a U-shaped pipe 10f having an oil return hole 10e of about several millimeters in the curved portion is arranged in the second chamber 10c. Immediately after the heat source device 100 is replaced, a predetermined amount of ester oil 10 is stored in the first chamber 10b.
g is retained.

In such a configuration, the HAB oil that has moved with the refrigerant is stored in the first chamber 10 of the accumulator 10.
Since it flows into b and mixes with the ester oil stored therein, the relative concentration of HAB oil decreases. When the amount of the refrigerating machine oil increases, the refrigerating machine oil flows over the weir 10a into the second chamber 10c, enters the U-shaped pipe 10f through the oil return hole 10e, and is sent to the compressor 1. Since the concentration of the ester oil in the machine oil is secured to some extent or more, the reliability of the compressor 1 is secured and the performance equivalent to that of the conventional one can be secured.

Fourth Embodiment 7 is a vertical sectional view of an accumulator according to Embodiment 4 of the present invention.
In this accumulator, a suction hole is provided in the refrigerant inlet pipe so that the refrigerant can be inserted into the inside from the lower part of the accumulator. In FIG. 7, the same components as those in FIG. 4 and the corresponding components are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 7, 9e is a refrigerant inlet pipe having an oil return hole 9f. The refrigerant inlet tube 9e has a suction hole 9f of U
The character tube 9c is inserted inside the lower part of the accumulator 9 so that it is below the oil return hole 9b and the opening at the tip is above the oil return hole 9b. The suction hole 9f is
It is a circle with a diameter of several millimeters. In the accumulator shown in FIG. 4, the HAB oil discharged from the refrigerant inlet pipe 9a and the ester oil secured in advance are not agitated, so that the HAB oil and the ester oil may have a concentration distribution depending on the location. However, in the accumulator shown in FIG. 7, the ester oil-rich refrigerating machine oil held in the accumulator 9 is sucked from the suction hole 9f of the refrigerant inlet pipe 9e,
Since the HAB oil is discharged into the accumulator 9 together with the HAB oil from the opening of the refrigerant inlet pipe 9e again, the HAB oil and the ester oil are well mixed and the concentration distribution of the refrigerating machine oil held in the accumulator 9 can be kept uniform. As described above, by making the concentration uniform, the refrigerating machine oil containing ester oil having a certain degree of concentration can be always sent to the compressor 1, and the reliability of the compressor 1 can be always ensured.

As shown in FIG. 8, the accumulator 10 shown in FIG. 6 has a refrigerant inlet pipe 10 having suction holes 10i.
From the bottom of the accumulator 10 to the first chamber 10b
It goes without saying that the concentration of the refrigerating machine oil held in the accumulator can be kept uniform by inserting it inside.

Embodiment 5. Not only the accumulator but also an oil separator may hold a certain amount of ester oil in advance and mix it with the HAB oil remaining in the existing pipe. 9 is a vertical cross-sectional view of an oil separator according to Embodiment 5 of the present invention, which is installed at the position of the oil separator 2 in the refrigeration cycle device of FIG. 11 in FIG.
Is an oil separator, which has an inlet pipe 11a for discharging the refrigerant gas from the compressor 1, an outlet pipe 11b connected to the condenser 3, and an oil return pipe 11c for returning the refrigerating machine oil to the compressor 1. is doing. The oil return pipe 11c is inserted inside the oil separator 11 so as to have a height hoil from the lower portion, and immediately after the heat source device 100 is replaced, the ester oil 11d is held up to the height hoil.

In such a structure, the HAB oil remaining in the indoor unit or the existing pipe in the refrigeration cycle apparatus is mixed with the ester oil in the accumulator 6 or the compressor 1 and diluted to some extent, and then the inlet pipe 11a is formed. More oil separator 11
Flows into the interior. Inside the oil separator 11, the inlet pipe 1
The refrigerating machine oil sent from 1a is mixed with the ester oil held inside, and the HAB oil is further diluted, and the concentration becomes smaller. Further, naturally, when the refrigerating machine oil exceeds the height hoil, the refrigerating machine oil inside the oil separator 11, that is, the refrigerating machine oil having a low HAB oil concentration, is returned to the inside of the compressor 1 from the oil return pipe 11c. .

As described above, by preliminarily holding the ester oil in the oil separator 11, the concentration of the HAB oil remaining in the existing piping etc. in the entire refrigerating machine oil can be reduced,
It is possible to secure the concentration of ester oil above a certain level,
The reliability of the operation of the compressor 1 can be improved and the performance of the refrigeration cycle device can be ensured.

Sixth Embodiment FIG. 10 is a refrigerant circuit diagram showing a refrigeration cycle apparatus according to Embodiment 6 of the present invention. In the refrigeration cycle apparatus of FIG. 1, an oil storage tank for holding refrigerating machine oil, and an oil collecting apparatus for collecting refrigerating machine oil are shown. Is added. In FIG. 10, the same components as those in FIG. 1 and corresponding components are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 10, reference numeral 12 is an oil storage tank, which is branched from a pipe connecting the outlet pipe of the oil separator 2 and the heat source side heat exchanger 3 and is connected via a capillary tube. The lower part of the oil storage tank 12 is installed in the compressor 1 and is connected by a pipe to an oil regulator 13 that detects the amount of refrigerating machine oil in the compressor 1. Immediately after the heat source machine is replaced, the oil storage tank 12 holds a predetermined amount of ester oil. Reference numeral 14 is a first electromagnetic valve provided in a pipe connecting the indoor heat exchanger 5 and the accumulator 6, and the upstream side (indoor heat exchanger side) and the downstream side with the first electromagnetic valve 14 interposed therebetween. A part of the pipe with the (accumulator side) is branched to form a first branch pipe 15 and a second branch pipe 16, respectively, and oil is supplied to the first branch pipe 15 and the second branch pipe 16. The recovery device 17 is connected. Further, FIG. 11 shows an oil recovery device 1
7 is a vertical cross-sectional view of FIG. 7, in which an inlet pipe 17 a connected to the first branch pipe 15 and an outlet pipe 17 b connected to the second branch pipe 16 are inserted into the upper surface of the oil recovery device 17. ing. A second solenoid valve 18 is provided in the first branch pipe 15.

Next, the operation of the refrigeration cycle apparatus having such a configuration will be described. When the compressor 1 operates, refrigerating machine oil is discharged from the compressor 1 to the oil separator 2 together with the refrigerant gas. Compressor 1 and oil regulator 1
3 is connected at the bottom, so that when the amount of refrigerating machine oil decreases, the oil level of the refrigerating machine oil in the compressor 1 and the oil level of the refrigerating machine oil in the oil regulator 13 become the same height. Therefore, when the oil level of the oil regulator 13 falls below a predetermined height, the valve installed in the oil regulator 13 opens and the oil is stored in the oil storage tank 12 using the high pressure and low pressure differential pressure to compress the oil. 1 is supplied. When the valve returns to a predetermined height, the valve closes again and the oil supply is stopped.

For a while (immediately after the replacement of the heat source unit) (this time is hereinafter referred to as "oil recovery time"), the first solenoid valve 14 is closed and the second solenoid valve 18 is opened to open the refrigeration cycle apparatus. To operate. As a result, due to the shearing force of the refrigerant gas discharged from the compressor 1, the HAB oil remaining in the existing pipe or the like moves with the refrigerant, the HAB oil flows in with the refrigerant from the inlet pipe 17a of the oil recovery device 17, and the HAB oil becomes the oil. Although it collects in the lower part of the recovery device 17, the refrigerant gas remains in the outlet pipe 1.
It will flow out from 7b. During the oil recovery time, the refrigerating machine oil does not return to the accumulator 6, so that a shortage of refrigerating machine oil in the compressor 1 occurs, but in this case,
Since the ester oil is sent from the oil storage tank 12 into the compressor 1, the shortage is immediately solved.

When the oil recovery time has elapsed, the first
The solenoid valve 14 is opened and the second solenoid valve 18 is closed. In this way, the remaining HAB oil can be recovered by the oil recovery device 17, so that the HAB oil concentration of the refrigerating machine oil sent to the compressor 1 can be made extremely small, and the reliability of the operation of the compressor 1 can be maintained. be able to.

Although an oil regulator is used to detect the oil level of the compressor 1 in FIG. 10, as shown in FIG. 12, a simple oil level detecting means 19 such as a float is used.
It is also possible to detect the oil level of the compressor 1 and control the opening / closing of the electromagnetic valve 21 by the control means 20 to adjust the amount of refrigerating machine oil in the compressor 1. Further, although the oil recovery time is set in advance, for example, when the concentration detector is provided in the inlet pipe 17a of the oil recovery device 17 and the HAB oil concentration becomes a predetermined value or less, the first solenoid valve 14, the second solenoid valve 18 is opened.
May be closed.

Embodiment 7. In the refrigeration cycle device shown in FIG. 10, the oil storage tank 12 is on the downstream side of the oil separator 2,
Since it is branched and connected from the pipe located at the upstream side of the heat source side heat exchanger 3, it is maintained at a high pressure. But,
If the refrigerating machine oil is maintained at a high temperature, it may deteriorate and generate sludge or the like. FIG. 13 is a refrigerant circuit diagram of a refrigeration cycle device according to Embodiment 7 of the present invention, in which the oil storage tank 12 can be held at an intermediate pressure. In addition, in FIG. 13, the same configuration as in FIG.
The same reference numerals are given to the corresponding components and the description thereof will be omitted.

In FIG. 13, reference numeral 22 is a pressure control means having a differential pressure valve, which is connected to the upper surface of the oil storage tank 12 and a pipe located upstream of the oil recovery device, and repeats opening and closing at regular time intervals. As a result, the refrigerant gas in the oil storage tank 12 is released to the pipe and the pressure is maintained at the intermediate pressure. With such a configuration, the refrigerating machine oil in the oil storage tank 12 does not reach a high temperature, and deterioration can be prevented. As shown in FIG. 14, the refrigeration cycle apparatus of FIG. 12 may be provided with pressure control means.

Embodiment 8. FIG. 15 is a refrigerant circuit diagram of the refrigeration cycle device according to Embodiment 8 of the present invention,
In the refrigeration cycle device of FIG. 1, an oil recovery device and the like are added, and a sump and a solenoid valve are provided on the downstream side of the heat source side heat exchanger to enable recovery of HAB oil during pump down operation. is there. In addition, in FIG. 15, FIG. 1 and FIG.
The same configurations and corresponding configurations are designated by the same reference numerals, and description thereof will be omitted.

In FIG. 15, a liquid sump 23 is connected downstream of the heat source side heat exchanger 3, and a third solenoid valve 24 for pump down operation is provided between the liquid sump 23 and the expansion valve 4. It is provided. The pump-down operation means that when the refrigeration cycle apparatus is stopped, the third solenoid valve 24 is closed and the refrigerant existing on the low pressure side is recovered in the liquid sump 23 installed on the high pressure side. It is an operation, and is usually performed when the refrigeration cycle apparatus, especially the refrigerator, is stopped.

Next, the operation will be described with reference to the flowchart of FIG. This operation is controlled by the control device (not shown) of the refrigeration cycle device. First, the liquid-refrigerant is held in the liquid reservoir 23 on the high-pressure side by performing the pump-down operation immediately after the heat source device is replaced (S1).
0). After the pump down operation for a certain period of time, the control device controls the third solenoid valve 2 with the refrigeration cycle device stopped.
4 is opened, the first solenoid valve 14 is closed, and the second solenoid valve 18 is opened.
Is opened (S11). As a result, the liquid refrigerant existing on the high pressure side passes through the third electromagnetic valve 24, flows to the expansion valve 4, is decompressed by the expansion valve 4, and becomes a low-pressure gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant passes through the indoor heat exchanger 5 and flows into the oil recovery device 17. As described above, when the gas-liquid two-phase refrigerant passes through the indoor heat exchanger 5 and the existing pipe, the HAB oil attached to the existing pipe also flows due to the shearing force, and the mixed liquid of the refrigerant and the HAB oil is generated. The oil will be collected in the oil recovery device 17.

When a certain amount of time passes and a certain amount of refrigerant flows, the pressure difference between the high pressure and the low pressure disappears, and the refrigerant stops flowing toward the expansion valve 4. Therefore, it is detected whether or not a certain time has passed (S12), and when the time has passed, the first electromagnetic valve 14 is opened, the second electromagnetic valve 18 is closed, and the refrigeration cycle apparatus is started (S13). Thus, only the refrigerant collected in the oil recovery device 17 can be evaporated and sucked into the compressor 1. Then, after a predetermined time has elapsed, the counter k (initially set to 0) is incremented (S1
4), it is determined whether or not it has been performed a prescribed number of times (n times) (S
15). If the specified number of times has not been performed, S
Returning to 10, the subsequent operation is performed. If the number of times has reached the specified number, the process ends.

By doing so, it becomes possible to collect the HAB oil remaining in the refrigeration cycle device in the oil recovery device 17.

Ninth Embodiment FIG. 17 is a refrigerant circuit diagram showing a refrigeration cycle device according to Embodiment 9 of the present invention.
In the refrigeration cycle apparatus of FIG. 15, when the refrigeration cycle apparatus is started after the defrost operation, the fact that the refrigerant in the gas-liquid two-phase state flows out from the indoor heat exchanger is used to recover the HAB oil. In FIG. 17, the same components as those in FIG. 15 and corresponding components are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 17, reference numeral 25 is a temperature type expansion valve, which is controlled by the temperature detected by a temperature sensing tube 25a provided on the downstream side of the indoor heat exchanger 5. Further, 5a is a heater provided in the indoor heat exchanger 4, which is energized during the defrost operation.

Next, the operation will be described with reference to the flowchart of FIG. First, the compressor 1 is stopped and the heater 5a is irrespective of whether frost is formed on the indoor heat exchanger 5.
Is energized (S20). As a result, the thermal expansion valve 25
The temperature of the temperature sensitive tube 25a rises, and the opening degree of the thermal expansion valve 25 correspondingly increases. After that, the temperature sensitive tube 25a
It is detected whether or not the temperature of has reached a predetermined value (S2
1) When reaching, the refrigerating cycle device is started after stopping energization of the heater 5a, and at the same time, the first solenoid valve 14
Is closed and the second solenoid valve 18 is opened (S22). In this case, since the opening degree of the thermal expansion valve 25 is large, the flow rate of the refrigerant supplied to the indoor heat exchanger 5 is large, and eventually the refrigerant in the gas-liquid two-phase state from the indoor heat exchanger 5 is increased. Will flow out. Therefore, H remaining in the existing pipe
The AB oil flows due to the shearing force of the refrigerant in the gas-liquid two-phase state and flows into the oil recovery device 17. In the oil recovery device 17, the refrigerating machine oil and the liquid refrigerant are accumulated, and the refrigerant gas is sent to the accumulator 6 through the outlet pipe 17b. When the refrigeration cycle device is continuously operated, the temperature of the temperature sensing cylinder 25a decreases and the opening degree of the temperature type expansion valve 25 also becomes an appropriate state, so the liquid refrigerant accumulated in the oil recovery device 17 evaporates. Therefore, only the refrigerating machine oil containing the HAB oil is present in the oil recovery device 17.

Thereafter, the counter k (initially set to 0) is incremented (S23), and after a predetermined time has elapsed (S2
4), it is determined whether or not it has been performed a prescribed number of times (n times) (S
25). If the specified number of times has not been performed, S
Returning to 10, the subsequent operation is performed. If the specified number of times has been reached, the first solenoid valve 14 is opened and the second solenoid valve 1 is opened.
After closing 8 (S26), the process ends.

As described above, by passing the gas-liquid two-phase refrigerant through the existing pipe, the remaining HAB oil can be pushed to the oil recovery device, the reliability of the operation of the compressor can be ensured, and the refrigeration cycle device The performance of can be maintained.

Embodiment 10. FIG. 19 is a refrigerant circuit diagram of the refrigeration cycle device shown in Embodiment 10 of the present invention. In the refrigeration cycle device of FIG. 17, the oil recovery device 1 is used.
7 is provided with an overheating means 26. Note that FIG.
Among them, the same configurations as those in FIG. 17 and the corresponding configurations are denoted by the same reference numerals, and the description thereof will be omitted.

In FIG. 19, reference numeral 26 is an overheating means such as a heater, which is inserted from the lower part of the oil recovery device 17 to the inside.
In such a configuration, at the stage of S22 of FIG. 18, by superheating the liquid stored in the oil recovery device 17 by the overheating means 26, only the liquid refrigerant can be vaporized into the refrigerant gas, which is unnecessary. Only refrigerating machine oil can be collected. In addition,
As shown in FIG. 20, a pipe on the downstream side of the oil separator 2 is inserted into the oil recovery device 17, and the heat of the high-pressure / high-temperature refrigerant gas flowing through this pipe is used to vaporize the liquid refrigerant. May be.

Eleventh Embodiment FIG. 21 is a refrigerant circuit diagram showing the configuration of the refrigeration cycle device in Embodiment 11 of the present invention. In the refrigeration cycle device of FIG.
The pressure and temperature are detected, and the operation of the heating means in the oil recovery device is controlled. In addition, in FIG.
The same configurations as those in FIG. 19 and the corresponding configurations are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 21, 27 is a pressure sensor for detecting the pressure of the second branch pipe 16 and 28 is a temperature sensor for detecting the temperature of the second branch pipe 16.
The detected data is transmitted to 9. In the calculation means 29, the pressure detected by the pressure sensor 27 and the temperature sensor 28
The energization of the heater 26 is controlled based on the temperature detected in.

Specifically, the saturation temperature Tsat of the refrigerant is calculated based on the pressure P detected by the pressure sensor 27,
This saturation temperature Tsat and the temperature T detected by the temperature sensor
The superheat degree SH = TsatT is calculated based on

When the liquid refrigerant is present in the oil recovery device 17, almost saturated gas flows into the outlet pipe 17b, so that SH = 0, and conversely, the liquid refrigerant is present in the oil recovery device 17. Without refrigerator oil, SH> 0
Become. Therefore, a value close to 0 is set as the specified value: SHbase, and when SH> SHbase, the oil recovery device 17
When it is determined that the liquid refrigerant does not exist in the heater 26, the heater 26 is not energized, and when SH <SHbase, the oil recovery device 17
It is determined that the liquid refrigerant is present in the heater, and the heater 26 is energized to evaporate the liquid refrigerant. By doing so, the heater is energized only when the liquid refrigerant is present in the oil recovery device 17, and efficient operation is possible.

[0066]

The first heat source machine is removed from the pipe, and the second heat source machine is removed.
After connecting the heat source machine of to the pipe, while evacuating,
Since the second refrigerating machine oil flows through the pipe until the ratio of the first refrigerating machine oil and the second refrigerating machine oil held in the accumulator of the second heat source machine reaches a predetermined value, the compressor has the second The refrigerating machine oil having a ratio of refrigerating machine oil of not less than a predetermined value is sent, and the reliability can be secured.

Since the first heat source unit is removed from the pipe and the second heat source unit in which the accumulator is filled with the predetermined amount of the second refrigerating machine oil is connected to the pipe, the ratio of the second refrigerating machine oil to the compressor is predetermined. The above refrigerating machine oil is sent and reliability can be secured.

Since the refrigerating machine oil sucked into the inlet pipe of the accumulator through the suction hole is discharged into the accumulator through the tip opening, the refrigerating machine oil concentration can be kept uniform.

Since the first heat source unit is removed from the pipe and the second heat source unit in which the oil separator is filled with the second refrigerating machine oil in a predetermined amount is connected to the pipe, the ratio of the second refrigerating machine oil to the compressor is However, the refrigerating machine oil of a predetermined amount or more is sent, and the reliability can be secured.

In the refrigeration cycle apparatus according to the present invention, the first solenoid valve provided between the indoor heat exchanger and the accumulator and the first solenoid valve formed by branching the upstream side of the first solenoid valve are formed. A branch pipe, a second branch pipe formed by branching the downstream side of the first solenoid valve, an oil recovery device connected to the first branch pipe and the second branch pipe, and a first branch pipe. When the second solenoid valve provided in the branch pipe, the oil storage tank for storing the refrigerating machine oil, and the refrigerating machine oil of the compressor are below a predetermined amount,
Since the refrigerating machine oil is supplied from the oil storage tank to the refrigerating machine oil, the refrigerating machine oil remaining in the existing pipe can be recovered.

Further, the supply means includes an oil level detection means for detecting the oil level of the refrigerating machine oil, a pipe connecting the oil storage tank and the compressor, a solenoid valve provided in the pipe, and an oil level detection means. Since it has a control means for controlling the opening / closing of the solenoid valve based on the detected information, it is possible to eliminate the oil shortage of the compressor.

Further, since the oil storage tank and the pressure equalizing pipe connecting the pipe located on the upstream side of the first solenoid valve and the pressure control means provided in the pressure equalizing pipe are provided, generation of sludge or the like is prevented. It can be prevented.

The first electromagnetic valve provided between the indoor heat exchanger and the accumulator, the first branch pipe formed by branching the upstream side of the first electromagnetic valve, and the second Since the second branch pipe formed by branching the downstream side of the solenoid valve and the oil recovery device connected to the first branch pipe and the second branch pipe are provided, refrigerating machine oil remaining in the existing pipe is removed. Can be collected.

Further, since the heating means for heating the liquid in the oil recovery device and the arithmetic device for controlling the heating means on the basis of the temperature and the pressure of the second branch pipe are provided, the liquid refrigerant in the oil recovery device is provided. Can be efficiently gasified.

In addition, the third solenoid valve is closed to perform the pump down operation, and then the compressor is stopped,
The second solenoid valve and the third solenoid valve are opened, the first solenoid valve is closed, and after a predetermined time has passed, the first solenoid valve is opened and the second solenoid valve is closed. Refrigerating machine oil remaining inside can be collected.

Further, after heating the indoor heat exchanger with the compressor stopped and the temperature-sensitive expansion valve detects a predetermined temperature, the first solenoid valve is closed and the second solenoid valve is opened. Since it is opened and the compressor is started, the refrigerating machine oil remaining in the pipe can be recovered.

Further, since the oil recovery device has a heater for heating the liquid stored therein, the liquid refrigerant in the oil recovery device can be efficiently gasified.

[Brief description of drawings]

FIG. 1 is a refrigerant circuit diagram of a refrigeration cycle device according to a first embodiment.

FIG. 2 is a flowchart of heat source device replacement of the refrigeration cycle device according to the first embodiment.

FIG. 3 is a refrigerant circuit diagram of the refrigeration cycle device in the second embodiment.

FIG. 4 is a vertical sectional view of an accumulator according to a second embodiment.

FIG. 5 is a vertical sectional view of an accumulator according to a second embodiment.

FIG. 6 is a vertical sectional view of an accumulator according to a third embodiment.

FIG. 7 is a vertical sectional view of an accumulator according to a fourth embodiment.

FIG. 8 is a vertical sectional view of an accumulator according to a fourth embodiment.

FIG. 9 is a vertical sectional view of an oil separator according to a fifth embodiment.

FIG. 10 is a refrigerant circuit diagram of the refrigeration cycle device in the sixth embodiment.

FIG. 11 is a vertical sectional view of an oil recovery device.

FIG. 12 is a refrigerant circuit diagram of the refrigeration cycle device in the sixth embodiment.

FIG. 13 is a refrigerant circuit diagram of the refrigeration cycle device in the seventh embodiment.

FIG. 14 is a refrigerant circuit diagram of the refrigeration cycle device in the seventh embodiment.

FIG. 15 is a refrigerant circuit diagram of the refrigeration cycle device in the eighth embodiment.

FIG. 16 is a flowchart showing an oil recovery operation.

FIG. 17 is a refrigerant circuit diagram of the refrigeration cycle device in the ninth embodiment.

FIG. 18 is a flowchart showing an oil recovery operation.

FIG. 19 is a refrigerant circuit diagram of the refrigeration cycle device in the tenth embodiment.

FIG. 20 is a refrigerant circuit diagram of the refrigeration cycle device in the tenth embodiment.

FIG. 21 is a refrigerant circuit diagram of the refrigeration cycle device in the eleventh embodiment.

[Explanation of symbols]

1 compressor, 2 oil separator, 3 heat source side heat exchanger,
4 expansion valve, 5 indoor heat exchanger, 5a heater,
6 accumulators, 7 capillaries for oil return, 8 ports, 9 accumulators, 9a refrigerant inlet pipe, 9b
Oil return hole, 9c U-shaped tube, 9d Ester oil, 9e
Refrigerant inlet pipe, 9f suction hole, 10 accumulator, 10a weir, 10b first chamber, 10c second chamber, 10d refrigerant inlet pipe, 10e oil return hole,
10f U-shaped pipe, 10g ester oil, 10h refrigerant inlet pipe, 10i suction hole, 11 oil separator, 11a
Inlet pipe, 11b outlet pipe, 11c oil return pipe,
11d ester oil, 12 oil storage tank, 13
Oil regulator, 14 first solenoid valve, 15 first branch pipe, 16 second branch pipe, 17 oil recovery device, 17a inlet pipe, 17b outlet pipe, 18 second
Solenoid valve, 19 oil level detection means, 20 control means,
21 solenoid valve, 22 pressure control means, 23 liquid reservoir,
24 Third Solenoid Valve, 25 Temperature Expansion Valve, 25a
Temperature sensing tube, 26 overheating means, 27 temperature sensor,
28 pressure sensor, 29 arithmetic unit, 100 heat source device, 200 indoor unit.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F25B 43/02 F25B 43/02 AD JN (72) Inventor Masao Kawasaki 2-2 Marunouchi, Chiyoda-ku, Tokyo No. 3 Sanryo Electric Co., Ltd. (72) Inventor Tetsuya Yamashita 2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd. (72) Inventor Takashi Ikeda 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd. (72) Inventor Hiromitsu Moriyama 2-3-3 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd. (72) Inventor Keizo Fukuhara 2-3-3 Marunouchi, Chiyoda-ku, Tokyo Inside Ryo Electric Co., Ltd.

Claims (13)

[Claims] 1. A first heat source device that operates using a first refrigerant and a first refrigerating machine oil, an indoor unit, and a pipe that connects the first heat source device and the indoor unit. Using the pipe of the first refrigeration cycle device, a second heat source device having a compressor, a heat source side heat exchanger, and an accumulator and operating using a second refrigerant and a second refrigerating machine oil is provided. A manufacturing method for manufacturing a second refrigeration cycle apparatus, comprising:
Removing the heat source device from the pipe and connecting the second heat source device to the pipe; and the first step of holding the second heat source device in the accumulator of the second heat source device while evacuating. A second flow of the second refrigerating machine oil into the pipe until the ratio of the refrigerating machine oil to the second refrigerating machine oil reaches a predetermined value.
The manufacturing method of the refrigerating cycle characterized by having the process of. 2. A first heat source device that operates using a first refrigerant and a first refrigerating machine oil, an indoor unit, and a pipe that connects the first heat source device and the indoor unit. Using the pipe of the first refrigeration cycle device, a second heat source device having a compressor, a heat source side heat exchanger, and an accumulator and operating using a second refrigerant and a second refrigerating machine oil is provided. A manufacturing method for manufacturing a second refrigeration cycle apparatus, comprising:
The method for manufacturing a refrigeration cycle apparatus, comprising: removing the heat source device from the pipe, and connecting the second heat source device in which the accumulator is filled with a predetermined amount of the second refrigerating machine oil to the pipe. 3. The accumulator is a container, a U-shaped tube inserted from the upper part of the container and having an oil return hole for sending the refrigerant gas to the compressor, and an upper part of the container to insert the refrigerant gas into the container. And a weir that divides the inside of the container into a first chamber in which the U-shaped pipe is arranged and a second chamber in which the inlet pipe is arranged, except for a predetermined upper space. The second refrigerating machine oil is filled in the second chamber in a predetermined amount, and the method for manufacturing a refrigeration cycle apparatus according to claim 2, wherein the second chamber oil is filled in a predetermined amount. 4. An accumulator, a container, and a U-shaped tube inserted from the upper part of the container to send a refrigerant gas to a compressor.
Inserted from the lower portion of the container, having an inlet pipe for discharging the refrigerant gas into the container, the oil return hole formed in the U-shaped pipe is higher than the suction hole formed in the inlet pipe,
The refrigeration cycle apparatus manufacturing method according to claim 2, wherein the inlet tube is arranged so as to be lower than a tip opening portion. 5. A first heat source device that operates using a first refrigerant and a first refrigerating machine oil, an indoor unit, and a pipe connecting the first heat source device and the indoor unit. A second refrigerant that has a compressor, a heat-source-side heat exchanger, an accumulator, and an oil separator and that operates using a second refrigerant and a second refrigerating machine oil by using the piping of the first refrigeration cycle apparatus. A second manufacturing method for manufacturing a second refrigeration cycle apparatus including a heat source device, wherein the first heat source device is removed from the pipe, and the oil separator is filled with a predetermined amount of the second refrigerating machine oil. A method for manufacturing a refrigeration cycle apparatus, comprising the step of connecting the heat source unit of claim 1 to the pipe. 6. A refrigeration cycle apparatus in which a compressor, an oil separator, a heat source side heat exchanger, an expansion valve, an indoor heat exchanger, and an accumulator are sequentially connected by piping, and the indoor side A first solenoid valve provided between a heat exchanger and the accumulator, a first branch pipe formed by branching an upstream side of the first solenoid valve, and a downstream of the first solenoid valve. A second branch pipe formed by branching the side, an oil recovery device connected to the first branch pipe and the second branch pipe, and a second branch pipe provided on the first branch pipe. An electromagnetic valve, an oil storage tank for storing refrigerating machine oil, and a supply means for supplying the refrigerating machine oil from the oil storing tank to the compressor when the refrigerating machine oil of the compressor falls below a predetermined amount. Refrigeration cycle device characterized by. 7. The supply means includes an oil level detection means for detecting an oil level of refrigerating machine oil, a pipe connecting the oil storage tank and the compressor, a solenoid valve provided in the pipe, and the oil. The refrigeration cycle apparatus according to claim 6, further comprising: a control unit that controls opening / closing of the electromagnetic valve based on information detected by the surface detection unit. 8. An equalizing pipe connecting an oil storage tank and a pipe located upstream of the first electromagnetic valve, and a pressure control means provided in the equalizing pipe. Item 6. The refrigeration cycle device according to item 6 or 7. 9. A refrigeration cycle apparatus in which a compressor, an oil separator, a heat source side heat exchanger, an expansion valve, an indoor side heat exchanger, and an accumulator are sequentially connected by piping, the indoor side A first solenoid valve provided between a heat exchanger and the accumulator, a first branch pipe formed by branching an upstream side of the first solenoid valve, and a downstream of the first solenoid valve. A refrigeration cycle apparatus comprising: a second branch pipe formed by branching a side, and an oil recovery device connected to the first branch pipe and the second branch pipe. 10. A heating device for heating the liquid in the oil recovery device, and a computing device for controlling the heating device based on the temperature and pressure of the second branch pipe. The refrigeration cycle apparatus according to 1. 11. A compressor, an oil separator, a heat source side heat exchanger, a liquid sump, an expansion valve, an indoor side heat exchanger, and an accumulator are sequentially connected by piping, and the indoor side heat exchanger. And a first solenoid valve provided between the accumulator and a first solenoid valve formed by branching the upstream side of the first solenoid valve.
A branch pipe, a second branch pipe formed by branching the downstream side of the first electromagnetic valve, and an oil recovery device connected to the first branch pipe and the second branch pipe, A method of operating a refrigeration cycle apparatus, comprising: a second electromagnetic valve provided in the first branch pipe; and a third electromagnetic valve provided between the liquid reservoir and the expansion valve, the method comprising: The first step of performing the pump down operation by closing the third solenoid valve, and the second solenoid valve and the third solenoid valve are opened with the compressor stopped, and the first step is performed. Refrigeration comprising a second step of closing the solenoid valve and a third step of opening the first solenoid valve and closing the second solenoid valve after a lapse of a predetermined time. How to operate the cycle device. 12. A compressor, an oil separator, a heat source side heat exchanger, a liquid sump, a temperature-sensitive expansion valve, an indoor side heat exchanger,
A first electromagnetic valve provided between the indoor heat exchanger and the accumulator, and an upstream side of the first electromagnetic valve, which is formed by branching the accumulators in a pipe connection. A pipe, a second branch pipe formed by branching the downstream side of the first electromagnetic valve, the first branch pipe and the second
An oil recovery device connected to the branch pipe, a second solenoid valve provided to the first branch pipe, and a third solenoid valve provided between the sump and the expansion valve. A method of operating a refrigeration cycle apparatus having: a first step of heating the indoor heat exchanger in a state in which the compressor is stopped; and, after the temperature-sensitive expansion valve detects a predetermined temperature, A second step of closing the first electromagnetic valve, opening the second electromagnetic valve, and starting the compressor, the operating method of the refrigeration cycle apparatus. 13. The oil recovery device has a heater for heating the liquid stored therein.
The method for operating the refrigeration cycle according to 1 or 12.