JP2000304387A - Refrigerant circulating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To raise an inlet temperature of a primary side of a conveyor heat exchanger and to improve a circulating velocity and circulating ratio of a refrigerant by directly supplying a primary refrigerant delivered from a compressor to the exchanger for pressurizing a secondary refrigerant. SOLUTION: When a high-temperature high-pressure primary refrigerant delivered from a compressor 41 flows to one of conveyor heat exchangers 7A, 7B through a four-way switching valve 42 directly as its high temperature remained, the valve 42 is switched in the state indicated by solid lines of the drawing, the primary refrigerant flows through the exchanger 7A, is condensed to heat the secondary refrigerant, and to raise its pressure. The secondary refrigerant obtains its conveying pressure as remained in its liquid phase by the raised pressure, that is, obtains a conveying force to flow out from the exchanger 7A and flows through the existing refrigerant piping 2A, 2B. The primary refrigerant passing through the exchanger 7A evaporates the secondary refrigerant stored in a tank 51 of a separator 50. Then, the condensed primary refrigerant is pressure-reduced through an air-cooled condenser 4a, pressure- reduced by an expansion valve EV, fed to the exchanger 7B, and the primary refrigerant is evaporated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerant circulating apparatus used for cleaning piping of a refrigeration system, recovering a refrigerant, or regenerating a refrigerant, and more particularly, to a measure for improving the circulation efficiency of the refrigerant. .

[0002]

2. Description of the Related Art Conventionally, many air conditioners have been known as refrigeration systems. For example, JP-A-8-
As disclosed in Japanese Patent No. 100944, a compressor, a four-way switching valve, an outdoor heat exchanger, an electric expansion valve, a receiver, and an indoor heat exchanger are sequentially connected by refrigerant piping to constitute an air conditioner. Some air conditioners are configured to perform a cooling operation and a heating operation.

At the time of renewal demand of various air conditioners including the above-mentioned air conditioners, existing refrigerant pipes may be diverted as they are. In this case, if the refrigerant of the existing refrigerant circuit and the refrigerant of the new refrigerant circuit are the same CFC-based refrigerant or HCFC-based refrigerant, the existing refrigerant piping can be used without much problem.

[0004] However, from the viewpoint of recent environmental problems, the newly installed refrigerant circuit includes a conventional CFC-based refrigerant and HC
It has been proposed to use an HFC (hydrofluorocarbon) -based refrigerant instead of the FC-based refrigerant.

[0005] In this case, in order to divert the existing refrigerant pipe, the inside of the refrigerant pipe must be cleaned.
That is, lubricating oil or dust is often attached to the inner surface of the existing refrigerant pipe. In particular, while mineral oil is used as a lubricating oil in conventional CFC-based refrigerants and the like, synthetic oil is used as a lubricating oil in an HFC-based refrigerant, so that mineral oil lubricating oil remains in existing refrigerant piping. In the newly installed refrigerant circuit, foreign matter (contamination) occurs, which causes a problem that the throttle mechanism is closed and the compressor is damaged.

Therefore, the applicant of the present application removes the outdoor unit and the indoor unit from the existing refrigerant pipe, attaches the pipe cleaning unit at the position of the outdoor unit, and attaches the communication pipe at the position of the indoor unit to form a pipe cleaning circuit. In addition, a device for cleaning refrigerant piping while circulating liquid refrigerant in the circuit has been proposed (Japanese Patent Application No. 9-2955641).
issue).

This device comprises a closed circuit (secondary refrigerant circuit) connected to an existing refrigerant pipe, and a conveying circuit (primary refrigerant circuit) for circulating a secondary refrigerant in the closed circuit. ) Is configured as a refrigerant circulation device. The transfer circuit is constituted by a refrigeration cycle having two transfer heat exchangers, and heats and cools the secondary refrigerant in the connection circuit in each heat exchanger to impart a transfer force to circulate the refrigerant. The foreign matter in the refrigerant is removed by a separator provided in the connection circuit.

[0008]

In this apparatus, an air-cooled condenser is provided in the transfer circuit on the discharge side of the compressor in order to suppress a high pressure rise. There has been a problem that the inlet temperature on the primary side of the exchanger is lowered, the extrusion speed of the secondary refrigerant is reduced, and the circulation efficiency of the refrigerant is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to improve the circulation speed and the circulation rate of a refrigerant by increasing the inlet temperature on the primary side of a transfer heat exchanger. Things.

[0010]

According to the present invention, the primary refrigerant is directly supplied from the compressor (41) to the transfer heat exchangers (7A, 7B) so as to increase the extruding speed of the secondary refrigerant. It was done.

More specifically, a first solution of the present invention is to add a secondary refrigerant in a secondary refrigerant circuit (13) to a primary refrigerant circuit (40) performing a vapor compression refrigeration cycle operation. It is premised on a refrigerant circulating device that pressurizes and circulates. The primary refrigerant discharged from the compressor (41) is directly supplied to the transfer heat exchangers (7A, 7B) that pressurize the secondary refrigerant.

[0012] A second solution taken by the present invention is:
In the first solution, an air-cooled condenser (4e) is connected upstream of the expansion mechanism (EV) of the primary refrigerant circuit (40).

[0013] A third solution taken by the present invention is:
In the first solving means, a separation for evaporating the secondary refrigerant by passing the primary refrigerant and removing foreign matters is provided downstream of the transfer heat exchangers (7A, 7B) of the primary refrigerant circuit (40). A vessel (50) is provided, and an air-cooled condenser (4e) is connected between the separator (50) and the downstream expansion mechanism (EV).

A fourth solution taken by the present invention is:
In the second or third solution, the fan (4f) of the air-cooled condenser (4e) is activated when the high-pressure pressure of the primary refrigerant circuit (40) is equal to or higher than a predetermined value, and is stopped when the high-pressure pressure is equal to or lower than the predetermined value. It is configured so that

[0015] The fifth solution taken by the present invention is:
In the second or third solution, the fan (4f) of the air-cooled condenser (4e) is connected to the upstream side of the expansion mechanism (EV).
It is configured to start when the next refrigerant contains gas.

[0016] A sixth solution taken by the present invention is:
In the first solving means, a separation for evaporating the secondary refrigerant by passing the primary refrigerant and removing foreign matters is provided downstream of the transfer heat exchangers (7A, 7B) of the primary refrigerant circuit (40). A vessel (50) is provided, and an air-cooled condenser (4e) is connected between the transfer heat exchangers (7A, 7B) and the separator (50).

Further, a seventh solution taken by the present invention is:
In the sixth solution, the fan (4f) of the air-cooled condenser (4e) is started when the high-pressure pressure of the primary refrigerant circuit (40) is equal to or higher than a predetermined value, and is stopped when the high-pressure pressure is equal to or lower than the predetermined value. It is composed.

An eighth solution taken by the present invention is:
In the sixth solution, the fan (4f) of the air-cooled condenser (4e) is activated when the amount of the secondary refrigerant in the separator (50) is equal to or less than a predetermined amount, and is stopped when the amount of the secondary refrigerant is equal to or more than the predetermined amount. It is configured so that

A ninth solution means adopted by the present invention is:
In the first solving means, a separation for evaporating the secondary refrigerant by passing the primary refrigerant and removing foreign matters is provided downstream of the transfer heat exchangers (7A, 7B) of the primary refrigerant circuit (40). A separator (50), a bypass passage (49) for the separator (50), and an air-cooled condenser (4e) in the bypass passage (49).

According to a tenth aspect of the present invention, in the ninth aspect, the primary refrigerant is separated from the separator (50) when the amount of the secondary refrigerant in the separator (50) is less than a predetermined amount. 50)
Is bypassed to flow to the air-cooled condenser (4e), and the fan (4f) of the air-cooled condenser (4e) is started, and when the air flow exceeds a predetermined amount, the air flows to the separator (50). is there.

According to the eleventh to nineteenth solutions of the present invention, a water-cooled condenser is provided instead of the air-cooled condenser (4e) in the second to the tenth solutions, respectively. In a tenth solution, an air-cooled condenser (4e)
The cooling water is circulated to the water-cooled condenser at the same timing as when the fan (4f) is started.

In the first solution, the secondary refrigerant circuit (1) is operated by the primary refrigerant circuit (40) that performs a vapor compression refrigeration cycle operation.
By pressurizing the secondary refrigerant of 3), the secondary refrigerant can be circulated and recovered or regenerated. Since the primary refrigerant discharged from the compressor (41) is directly supplied to the carrier heat exchangers (7A, 7B) for pressurizing the secondary refrigerant, the carrier heat exchangers (7A, 7B) The primary inlet temperature rises, and the degree of superheat of the secondary refrigerant can be increased.

In the second solution, the air-cooled condenser (4e) is connected to the upstream side of the expansion mechanism (EV) of the primary-side refrigerant circuit (40). When the temperature rises excessively, the air-cooled condenser (4e) is operated to suppress the high pressure rise.

In the third solution, the separator (50) is further provided in the primary refrigerant circuit (40).
When circulating the secondary refrigerant in the secondary refrigerant circuit (13), foreign substances can be removed from the secondary refrigerant.

Further, in the fourth solution, a rise in high pressure on the primary side can be prevented. In particular, for example, when the secondary side refrigerant flows into the separator (50) and contains gaseous refrigerant, When the condensing capacity in (50) is insufficient and the high pressure on the primary side rises, the insufficient cooling capacity can be compensated for by starting the fan (4f) of the air-cooled condenser (4e).

In the fifth solution, when the primary refrigerant on the upstream side of the expansion mechanism (EV) contains gas (flashes) and cannot be supercooled, When the fan (4f) of the air-cooled condenser (4e) is started,
The gas-phase refrigerant can be condensed and a liquid seal can be made before the expansion mechanism (EV).

In the sixth solution, the primary refrigerant circuit (40) is provided with a separator (50) for evaporating the secondary refrigerant by passing the primary refrigerant to remove foreign substances, and Since the air-cooled condenser (4e) is connected between the separator (50) and the transfer heat exchangers (7A, 7B), the air-cooled condenser (4e) fan ( 4f) is activated when the high pressure of the primary refrigerant circuit (40) is equal to or higher than a predetermined value, and is stopped when the high pressure is equal to or lower than the predetermined value. The temperature of the separator (50) can be lowered while adjusting the temperature.

Further, in the above-mentioned eighth solution, the fan (4f) of the air-cooled condenser (4e) is activated when the amount of the secondary refrigerant in the separator (50) is less than a predetermined amount, and If it is above, it is configured to stop.
When the amount of the secondary refrigerant is small, the temperature of the separator (50) tends to increase, while the temperature can be decreased.

In the ninth solution, the primary refrigerant circuit (40) is provided with a separator (50) for evaporating the secondary refrigerant by passing the primary refrigerant to remove foreign matter, The bypass passage (49) of the separator (50) is provided, and the air-cooled condenser (4e) is provided in the bypass passage (49).
When the amount of the secondary refrigerant in the separator (50) is equal to or less than a predetermined amount, the primary refrigerant bypasses the separator (50) and flows to the air-cooled condenser (4e). The fan (4f) of the air-cooled condenser (4e) is started, and if the amount exceeds a predetermined amount, the fan (4f) is allowed to flow through the separator (50).
Temperature can be lowered. That is, when the amount of the secondary refrigerant in the separator (50) is small, the primary refrigerant is not supplied more than necessary, thereby preventing the temperature of the separator (50) from rising.

Further, the eleventh to nineteenth aspects of the present invention are provided.
In the solution of (1), a water-cooled condenser is provided instead of the air-cooled condenser (4e) of the second to tenth solutions, and the air-cooled condenser (4
Since the cooling water is circulated to the water-cooled condenser at the same timing instead of starting the fan (4f) in e), the same operation as the second to tenth solving means is achieved.

[0031]

According to the first aspect of the present invention, the primary inlet temperature of the transfer heat exchangers (7A, 7B) is increased, so that the secondary refrigerant is extruded at a higher speed and the refrigerant circulation speed or the refrigerant circulation speed is increased. The circulation efficiency can be increased. Also, if you do this,
Since the degree of superheating of the secondary refrigerant is increased, it is possible to prevent the secondary refrigerant from remaining in the pipe during recovery.

Further, according to the second and third means, it is possible to prevent an increase in the high pressure on the primary side. In particular, according to the third means, foreign matters are removed during circulation of the secondary refrigerant. Since it is possible, the pipe can be cleaned.

According to the fourth solution, the fan (4f) of the air-cooled condenser (4e) is started when the high pressure of the primary refrigerant circuit (40) becomes higher than a predetermined value. Thereby, the shortage of the condensation capacity in the separator (50) can be compensated. That is, the high pressure of the primary refrigerant can be adjusted.

Further, according to the fifth aspect of the present invention, since the liquid sealing can be performed in front of the expansion mechanism (EV), the operation of the expansion mechanism (EV) can be ensured, and the primary refrigerant has a sufficient passage resistance. Can be given. Therefore, a decrease in capacity and a decrease in reliability of the machine can be prevented, and a running out of gas does not occur. Further, since the refrigerant can be saved as described above, the liquid back to the compressor can be reduced.

According to the sixth to eighth solutions, the air-cooled condenser (7) is provided between the separator (50) of the primary refrigerant circuit (40) and the transfer heat exchangers (7A, 7B). 4e) is connected to start the fan (4f) of the air-cooled condenser (4e) when the high pressure of the primary refrigerant circuit (40) exceeds a predetermined value. In addition, the high-pressure pressure of the primary-side refrigerant can be adjusted. In addition, since the temperature rise of the separator (50) can be prevented, the secondary refrigerant can be smoothly passed through the separator (50), and the circulation efficiency can be increased.

According to the ninth and tenth solutions, the temperature of the separator (50) can be reduced by controlling the supply amount of the primary refrigerant to the separator (50). The refrigerant on the secondary side can be smoothly poured into the separator (50), and the circulation rate of the secondary refrigerant can be increased.

Further, according to the eleventh to nineteenth solving means, the same effects as those of the second to tenth solving means can be obtained, so that the same effects can be obtained.

[0038]

Embodiment 1 Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to the drawings. This embodiment is an example in which the refrigerant circulation device of the present invention is applied to a pipe cleaning device.

As shown in FIG. 1, a pipe cleaning device (10)
Is for cleaning the refrigerant pipes (2A, 2B) in the existing refrigerant circuit using the secondary refrigerant system, and is connected to the existing refrigerant pipes (2A, 2B). FIG. 1 shows two existing refrigerant pipes (2A, 2B). The existing refrigerant pipes (2A, 2B) are communication pipes for connecting the outdoor unit and the indoor unit in an existing refrigerant circuit (not shown), and constitute a refrigerant injection section. In the present embodiment, they are vertical pipes. I have.

A first cleaning circuit (11) is connected to one end of the two existing refrigerant pipes (2A, 2B), and a second cleaning circuit (12) is connected to the other end. The first cleaning circuit (11)
Consists of one connection pipe, and both ends are joints (21, 21)
And connected to two existing refrigerant pipes (2A, 2B). The connection portion of the first cleaning circuit (11) is, for example, a portion to which the indoor unit is connected in the existing refrigerant circuit.

The second cleaning circuit (12) includes a connection circuit (3
0) and a refrigeration circuit (primary refrigerant circuit) (40). Both ends of the connection circuit (30) are joints (21, 21).
And connected to two existing refrigerant pipes (2A, 2B). Then, the two existing refrigerant pipes (2A, 2B) and the first
Connection circuit (30) for cleaning circuit (11) and second cleaning circuit (12)
A closed circuit (secondary-side refrigerant circuit) (13) is configured by the above. The connection portion of the connection circuit (30) is, for example, a portion to which an outdoor unit is connected in an existing refrigerant circuit.

The closed circuit (13) is connected to the existing refrigerant pipe (2A,
The secondary refrigerant for cleaning for cleaning 2B) is filled to form a refrigerant flow passage. As the secondary refrigerant, for example, a new clean refrigerant used in a newly installed air conditioner is used. Specifically, the secondary refrigerant is R-407C or R-407C.
HFC refrigerant such as -410A.

The connection circuit (30) includes a first closing valve (V1)
And check valve (31), separator (50), pressurizing and depressurizing part (60) and second
The shutoff valve (V2) is sequentially connected by a connection pipe (34).

The pressurizing and depressurizing section (60) forms two parallel passages (61, 61) in the middle of the connection pipe (34), and includes a first transfer heat exchanger (7A) and a second transfer heat exchanger. (7B) is provided in each parallel passage (61, 61). Furthermore, each transfer heat exchanger (7A,
On the upstream side and the downstream side of 7B), check valves (62, 62,...) Which allow the refrigerant to flow only in one direction are provided.

The separator (50) includes a tank (51) in which a separation heat exchange coil (52) and a filter (53) are housed, and includes a separation means for separating foreign matter such as lubricating oil from a secondary refrigerant. Make up. The tank (51) stores the liquid-phase secondary refrigerant flowing through the existing refrigerant pipes (2A, 2B).

The separation heat exchange coil (52) is connected to the refrigeration circuit (40) and constitutes heating means for heating and evaporating the liquid-phase secondary refrigerant in the tank (51). The filter (53) is attached to the upper part in the tank (51),
A collecting means for removing foreign matter from the secondary refrigerant by passing the secondary refrigerant in the gas phase evaporated by heating the separation heat exchange coil (52) is provided.

The refrigeration circuit (40) includes a compression circuit (4C)
And a transfer circuit section (4A) to constitute transfer means of one independent refrigeration cycle. The transfer circuit section (4A)
Is connected to the compression circuit section (4C) by a four-way switching valve (42) so that the flow direction of the refrigerant is reversible.
As the refrigerant to be charged in the refrigeration circuit (40), that is, the primary refrigerant, various refrigerants such as an HFC-based refrigerant other than R22 are used.

The compression circuit section (4C) is provided with an accumulator (46) on the suction side of the compressor (41). On the other hand, the transfer circuit section (4A) includes a first transfer heat exchanger (7A), a rectifier circuit (47), and a second transfer heat exchanger (7B) connected in series. The one-way passage (48) is connected to the rectifier circuit (47).

The rectifier circuit (47) is configured as a bridge circuit having four one-way valves (CV). Of the four connection points of the rectifier circuit (47), two connection points
The directional passage (48) is connected, and the other two connection points are respectively connected to the first transfer heat exchanger (7A) and the second transfer heat exchanger (7A).
B) is connected.

The one-way passage (48) is connected in order from the upstream with a separated heat exchange coil (52), an air-cooled condenser, and an expansion valve (expansion mechanism) (EV). The expansion valve (EV)
Constitutes a throttling mechanism whose degree of superheat is controlled. The temperature sensing cylinder (TB) of the expansion valve (EV) is attached to the inflow side of the accumulator (46). The above separated heat exchange coil (5
2) is stored in the tank (51) of the separator (50) as described above.

The air-cooled condenser (4e) is connected upstream of the expansion valve (EV), specifically, between the expansion valve (EV) and the separator (50). This air-cooled condenser (4e) always keeps the primary refrigerant before the expansion valve (EV) in a liquid-sealed state, and when the secondary-side refrigerant is not in the liquid phase when flowing into the separator (50), Is provided in consideration of the fact that the condensing ability may be insufficient.

The two transfer heat exchangers (7A, 7B) are, for example, plate heat exchangers. Each of the transfer heat exchangers (7A, 7B) is configured to alternately repeat a cooling operation and a pressurizing operation. That is, each of the transfer heat exchangers (7A, 7B) alternately serves as a cooling unit and a pressurizing unit.

The above cooling operation is an operation of cooling the gas-phase secondary refrigerant having undergone the phase change in the separator (50) to change the phase to the liquid phase and to reduce the pressure. The pressurizing operation is an operation of heating and pressurizing the liquid-phase secondary refrigerant in a liquid-phase state.

Specifically, for example, in a state where the secondary refrigerant in the liquid phase for washing is stored in the first transfer heat exchanger (7A) on the left side of FIG. 1, the second transfer heat exchange on the right side of FIG. The vessel (7B) is in a state in which the secondary refrigerant in the gas phase for cleaning is stored. In this state, the first transfer heat exchanger (7A) serves as a pressurizing unit, and the second transfer heat exchanger (7B) serves as a cooling unit.

The high-temperature primary refrigerant discharged from the compressor (41) sufficiently heats the liquid-phase secondary refrigerant in the first transport heat exchanger (7A) to increase the pressure, and imparts a transport pressure to the secondary refrigerant. The next refrigerant is pushed out to the existing refrigerant pipes (2A, 2B). On the other hand, the above 1
The secondary refrigerant passes through the separation heat exchange coil (52), and then expands (EV)
And evaporates in the second transfer heat exchanger (7B). The primary refrigerant cools the gas-phase secondary refrigerant, changes the phase of the secondary refrigerant into a liquid phase, and reduces the pressure. As a result, the second transfer heat exchanger (7B) sucks the gas-phase secondary refrigerant from the separator (50) and stores the secondary refrigerant.

Thereafter, the first transfer heat exchanger (7A) is switched to the cooling means, and the second transfer heat exchanger (7B) is switched to the pressurizing means. The high temperature 1 discharged from the compressor (41)
The secondary refrigerant flows into the second transfer heat exchanger (7B), and pushes out the liquid-phase secondary refrigerant into the existing refrigerant pipes (2A, 2B). On the other hand, the primary refrigerant evaporates in the first transport heat exchanger (7A), cools the gas phase secondary refrigerant, and stores the secondary refrigerant in the first transport heat exchanger (7A). This operation is repeated.

The compression circuit (4C) is provided with a low-pressure pressure sensor (P1) on the suction side of the compressor (41).
High pressure sensor (P2) and temperature sensor (T
2) is provided. In the connection pipe (34) of the connection circuit (30), a low pressure switch (LPS) is provided downstream of the separator (50).

The refrigeration circuit (40) controls whether the discharge pressure of the compressor (41) is higher than a predetermined value, the discharge temperature of the compressor (41) is lower than a predetermined value, The four-way switching valve (42) is configured to switch when the internal pressure becomes equal to or higher than a predetermined value or when any of the conditions is satisfied. In the refrigeration circuit (40), the flow direction of the refrigerant in the transfer circuit section (4A) is switched by switching the four-way switching valve (42).

For example, one transfer heat exchanger (7A, 7B)
When the (cooling side) is full of the liquid-phase secondary refrigerant, the heat exchange amount of the primary refrigerant in the transfer heat exchangers (7A, 7B) decreases. As a result, since the degree of superheating of the expansion valve (EV) is controlled, the throttle amount increases, and the low pressure on the suction side of the compressor (41) decreases. This low pressure is a low pressure sensor (P1)
Is detected, and when it becomes equal to or less than a predetermined value, the four-way switching valve (42) is switched.

The connection circuit (30) is provided with a hot gas passage (15) for charging and recovering the secondary refrigerant and an auxiliary circuit (90). That is, the pipe cleaning device (10) of the present embodiment is configured to function as a refrigerant recovery device that recovers the secondary refrigerant in addition to the pipe cleaning.

The hot gas passage (15) supplies the high-temperature and high-pressure secondary refrigerant to the existing refrigerant pipes (2A, 2B) after the completion of the cleaning, and remains in the existing refrigerant pipes (2A, 2B). The secondary refrigerant liquid is evaporated and collected. The inflow side of the hot gas passage (15) is branched into two, and two inflow ends are connected to the parallel passages (61, 6) on the inflow side of each transfer heat exchanger (7A, 7B).
1) Connected. In addition, the hot gas passage (1
The outflow end of 5) is connected between the second shutoff valve (V2) and the existing pipe (2B). A one-way valve (CV) is provided at a branch portion on the inflow side of the hot gas passage (15), and a third closing valve (V3) is provided at a collecting portion on the outflow side.

The auxiliary circuit (90) includes a refrigerant cylinder (91) as a container and four auxiliary passages (92 to 95).

The first auxiliary passage (92) is branched from the main portion on the inflow side into two on the outflow side. The inflow end of the first auxiliary passage (92) communicates with the refrigerant cylinder (91), and the two outflow ends are connected to the respective parallel passages (61, 61) downstream of the connection of the hot gas passage (15). It is connected. In the first auxiliary passage (92), a fourth closing valve (V4) is provided in a main portion on the inflow side, and a one-way valve (CV) is provided in a branch portion on the outflow side.

The third auxiliary passage (94) is provided with a sixth closing valve (V6).
Is provided. One end of the third auxiliary passage (94) is in communication with the refrigerant cylinder (91), and the other end is connected to the second transfer heat exchanger (7).
It is connected to the parallel passage (61) on the outflow side of B).

The second auxiliary passage (93) is provided with a fifth closing valve (V5).
Is provided. One end of the second auxiliary passage (93) is
The third auxiliary passage (94) is connected downstream of the sixth closing valve (V6), and the other end is connected to the main portion of the first auxiliary passage (92) downstream of the fourth closing valve (V4). It is connected.

The fourth auxiliary passage (95) is provided with a seventh closing valve (V7)
Is provided. One end of the fourth auxiliary passage (95) is
The other end of the first auxiliary passage (9) is connected to the collecting portion of the hot gas passage (15) upstream of the third shutoff valve (V3).
It is connected to the main part of 2) on the upstream side of the fourth closing valve (V4).

Then, a charging circuit (9S) for charging the closed circuit (13) with the secondary refrigerant includes a part of the hot gas passage (15), a fourth auxiliary passage (95), and a second auxiliary passage (95). The auxiliary passage (93) is formed by a part of the first auxiliary passage (92) and a part of the third auxiliary passage (94).

The recovery circuit (9R) for recovering the secondary refrigerant into the refrigerant cylinder (91) includes the hot gas passage (15), the first auxiliary passage (92), and the third auxiliary passage (9). 94)
And is formed by.

The refrigeration circuit (40) is controlled by a controller. The controller is provided with a control unit while inputting detection signals of the low-pressure pressure sensor (P1), high-pressure pressure sensor (P2), temperature sensor (T2), and low-pressure pressure switch (LPS).

The controller starts the fan (4f) of the air-cooled condenser (4e) when the high pressure on the primary side rises and reaches 18 kg / cm ² , as shown in FIG. 13 drops
It is configured to stop the fan (4f) of the air-cooled condenser (4e) when Kg / cm ² is reached. However, these values are merely examples, that is, the fan (4f) of the air-cooled condenser (4e) is activated when the high-pressure pressure of the primary refrigerant circuit (40) rises above an appropriate set value, What is necessary is just to comprise so that it may stop if it falls below that. That is, in some cases, the pressure is not distinguished between the on and off pressures.
^The configuration may be such that the fan (4f) of the air-cooled condenser (4e) is started when the number becomes ² or more, and stopped when the number becomes ² or less.

The controller also controls the air-cooled condenser (4e) when the primary refrigerant upstream of the expansion valve (EV) contains gas (flashes) and cannot be supercooled. The fan (4f) is configured to start. For example,
When the four-way switching valve (42) is switched so that one of the transfer heat exchangers (7A, 7B) that had previously functioned as an evaporator becomes a condenser, the high-pressure refrigerant on the primary side cools the cold transfer heat exchange. By passing through the separator, the refrigerant becomes condensed cold refrigerant and flows to the separator (50). At this time, the primary refrigerant evaporates because the temperature of the separator (50) is higher than that of the primary refrigerant. Such is the case.

<Cleaning Operation of Existing Refrigerant Pipes (2A, 2B)> Next, the cleaning operation of the existing refrigerant pipes (2A, 2B) by the above-described pipe cleaning device will be described, including the recovery operation.

First, in the existing refrigerant circuit, the outdoor unit and the indoor unit are removed from the existing refrigerant pipes (2A, 2B), which are communication pipes. Thereafter, a first cleaning circuit (11) is connected to the lower ends of the two existing refrigerant pipes (2A, 2B), while a second cleaning circuit is connected to the upper ends of the two existing refrigerant pipes (2A, 2B). Closed circuit (13) by connecting connection circuit (30) of (12)
To form

Subsequently, the secondary refrigerant is charged into the closed circuit (13). That is, in the initial stage of filling, for example, the closed circuit (13) is evacuated, and the refrigerant cylinder (91) is connected to the first auxiliary passage (92). Then, the fourth closing valve (V4) is opened, and the secondary refrigerant is charged from the refrigerant cylinder (91) into the closed circuit (13) through the first auxiliary passage (92).

Further, when the secondary refrigerant is additionally charged, in the auxiliary circuit (90), the third closing valve (V3), the fourth closing valve (V4), and the sixth closing valve (V6) are closed. Open the seventh closing valve (V7) and the fifth closing valve (V5).

In this state, when the refrigeration circuit (40) is driven, the hot gas in the closed circuit (13) flows from the upstream side of the transfer heat exchangers (7A, 7B) through the hot gas passage (15) to the fourth auxiliary passage. The refrigerant flows into the refrigerant cylinder (91) via (95). The hot gas pressurizes the interior of the refrigerant cylinder (91), and the refrigerant in the refrigerant cylinder (91), that is, the secondary refrigerant, passes from the third auxiliary passage (94) to the second auxiliary passage (93). The closed circuit (13) is filled through the first auxiliary passage (92).

Subsequently, the operation proceeds to the pipe cleaning operation,
The refrigeration circuit (40) of the second cleaning circuit (12) is driven while the closing valves (V3) to the seventh closing valve (V7) are closed. That is, the compressor (41) is driven to circulate the primary refrigerant. The high-temperature and high-pressure primary refrigerant discharged from the compressor (41) directly flows into one of the transfer heat exchangers (7A or 7B) at a high temperature via the four-way switching valve (42).

Then, in a state where the secondary refrigerant in the liquid phase for washing is stored in the first transfer heat exchanger (7A) on the left side of FIG.
A description will be given of a state in which the gas-phase secondary refrigerant for cleaning is accumulated in the second transfer heat exchanger (7B) on the right side of FIG.

In this state, the four-way switching valve (42) switches to the solid line state in FIG. 1, and the high-temperature primary refrigerant flows through the first transfer heat exchanger (7A), and the primary refrigerant condenses. Liquid phase 2
The next refrigerant is heated sufficiently to increase the pressure. Due to this pressurization, the secondary refrigerant obtains the transfer pressure in the liquid phase, that is, obtains the transfer force, flows out of the first transfer heat exchanger (7A), flows through the existing refrigerant pipe (2A,
2B).

At this time, the secondary refrigerant first flows through the existing refrigerant pipe (2B) on the large-diameter gas side, and flows through the first cleaning circuit (11).
Through the existing refrigerant pipe (2A) on the liquid side with a small diameter.

The primary refrigerant that has passed through the first transfer heat exchanger (7A) passes through the rectifier circuit (47) and the one-way passage (48), and passes through the separation heat exchange coil (52) of the separator (50). And evaporates the liquid-phase secondary refrigerant stored in the tank (51) of the separator (50).

Thereafter, the condensed primary refrigerant passes through the air-cooled condenser (4e), is decompressed by the expansion valve (EV), flows to the second transfer heat exchanger (7B), and the primary refrigerant evaporates. I do. By this evaporation, the secondary refrigerant in the gas phase for cleaning is cooled and changes into a liquid phase. Due to this phase change, the secondary refrigerant is depressurized and sucks the gas-phase secondary refrigerant from the separator (50), and stores the secondary refrigerant in the second transfer heat exchanger (7B).

By providing the air-cooled condenser (4e) at this position, if the gas refrigerant is contained when the secondary refrigerant flows into the separator (50), for example,
And the high pressure on the primary side rises above a predetermined value. In such a case, the shortage of the condensation capacity can be compensated. That is, the high pressure of the primary refrigerant can be adjusted. Further, when the air-cooled condenser (4e) is operated, the flash gas of the primary refrigerant can be eliminated, so that a liquid seal can be made before the expansion valve (EV).

On the other hand, the primary refrigerant evaporated in the second transfer heat exchanger (7B) passes through the four-way switching valve (42) to the compressor (41).
And this operation is repeated.

Thereafter, when the second transfer heat exchanger (7B) is full of the liquid-phase secondary refrigerant, the four-way switching valve (42) is switched. That is, when the amount of heat exchange of the primary refrigerant in the second transfer heat exchanger (7B) decreases, the expansion valve (EV) controls the degree of superheat, so the throttle amount increases, and the compressor (4
1) The low pressure on the suction side decreases. And, for example,
The low pressure sensor (P1) detects this low pressure and switches the four-way switching valve (42) when the pressure becomes equal to or less than a predetermined value.

By the switching of the four-way switching valve (42), the primary refrigerant discharged from the compressor (41) flows to the second transfer heat exchanger (7B), and the secondary refrigerant flows to the existing refrigerant pipes (2A, 2B). )
To send to. On the other hand, the primary refrigerant is a separated heat exchange coil (52)
After that, the secondary refrigerant is evaporated by the first transfer heat exchanger (7A) to cool the secondary refrigerant and to store the secondary refrigerant. Repeat this operation for 2
The next refrigerant is circulated in the closed circuit (13).

The liquid-phase secondary refrigerant is supplied to the existing refrigerant pipe (2
A, 2B), and foreign substances such as lubricating oil adhering to the inner surfaces of the existing refrigerant pipes (2A, 2B) dissolve. This secondary refrigerant is
In the separator (50), the heat is evaporated by the separation heat exchange coil (52), and the foreign matter is separated and accumulated in the tank (51). At the same time, when the secondary refrigerant passes through the filter (53), foreign substances such as lubricating oil mixed in the secondary refrigerant are removed, and the secondary refrigerant flows to the above-described one transfer heat exchanger (7A or 7B). This operation is repeated.

During the transfer of the secondary refrigerant, if the amount of condensation of the primary refrigerant in the transfer heat exchanger (7A or 7B) decreases,
The high pressure on the discharge side of the compressor (41) increases. This high pressure is detected by the high pressure sensor (P2), and when the pressure becomes equal to or higher than a predetermined value, the air cooling fan (4f) is driven. This allows
The amount of condensation of the primary refrigerant increases, and the high pressure of the primary refrigerant decreases.

When the secondary refrigerant is transported,
Also when gas refrigerant is contained when the secondary refrigerant flows into the separator (50), the condensing capacity of the separator (50) is insufficient, and the high pressure on the primary side rises to a predetermined value or more. Therefore,
This high pressure is detected by the high pressure sensor (P2), and when it reaches a predetermined value (18 kg / cm ² in this embodiment) or more, the air cooling fan (4f) is driven. As a result, the high pressure of the refrigerant on the primary side can be adjusted by compensating for the shortage of the condensation capacity.

Further, even when the primary refrigerant on the upstream side of the expansion valve (EV) contains gas (flashes) and cannot be supercooled, the fan (4e) of the air-cooled condenser (4e) can be used.
Start f). This allows the gas-phase refrigerant to be condensed and a liquid seal in front of the expansion valve (EV) to ensure operation of the expansion valve.

After the completion of the washing operation, a recovery operation of the secondary refrigerant is performed. That is, while the second closing valve (V2), the fifth closing valve (V5), and the seventh closing valve (V7) are closed, the first closing valve (V1), the third closing valve (V3), and the fourth closing valve. (V4) and the sixth closing valve (V6) are opened.

[0092] According to this valve state, the refrigeration circuit (4
0) is continuously driven, and the hot gas in the closed circuit (13) is supplied from the hot gas passage (15) to the existing refrigerant pipes (2A, 2B) and the like. That is, in the transfer heat exchanger (7A or 7B) in which the secondary refrigerant is heated and pressurized, the secondary refrigerant has the highest temperature and pressure immediately before switching the four-way switching valve (42).
For this reason, the secondary refrigerant in the high-temperature and high-pressure gas phase is sent out from the hot gas passage (15) to the existing refrigerant pipes (2A, 2B). The high-temperature secondary refrigerant evaporates and extrudes the liquid-phase secondary refrigerant remaining in the existing refrigerant pipes (2A, 2B).

On the other hand, the refrigerant cylinder (91) is connected to the first auxiliary passage (92) and the third auxiliary passage (94). Then, the opening of the fourth closing valve (V4) allows the first auxiliary passage (92) to communicate with the transfer heat exchanger (7A or 7B) that cools and lowers the pressure of the secondary refrigerant. By this communication, the refrigerant cylinder (91) is degassed, and the pressure in the refrigerant cylinder (91) becomes low.

In this state, the four-way switching valve (42)
And the extruding operation and the accumulating operation of both transfer heat exchangers (7A or 7B) are continuously performed. Since the third auxiliary passage (94) communicates with the refrigerant cylinder (91) by the opening of the sixth closing valve (V6), the third auxiliary passage (94) is pushed out from one of the transfer heat exchangers (7A or 7B). The secondary refrigerant is collected in the refrigerant cylinder (91) via the third auxiliary passage (94).

Thereafter, when the low pressure switch (LPS) is operated, the collecting operation ends. That is, when the secondary refrigerant in the closed circuit (13) is almost recovered, the pressure of the secondary refrigerant becomes low. Therefore, the end of the recovery operation is determined based on the low pressure switch (LPS). After the completion of the refrigerant recovery, the first cleaning circuit (11) and the second cleaning circuit (12) are removed from the existing refrigerant pipes (2A, 2B).

Note that even during the recovery operation, the air-cooled condenser (4e)
The operation of the fan (4f) is controlled in the same manner as during the cleaning operation. Therefore, it is possible to prevent the high pressure on the primary side from excessively rising, and to seal the liquid before the expansion valve (EV).

<Effects of First Embodiment> As described above, according to the first embodiment, the refrigerant discharged from the compressor (41) is supplied directly to one of the transfer heat exchangers (7A, 7B). Therefore, the inlet-side temperature can be sufficiently increased, and the recovery speed and the recovery rate of the secondary refrigerant can be increased. On the other hand, since the air-cooled condenser (4e) is provided between the separator (50) and the expansion valve (EV), it is possible to prevent the primary high pressure from rising more than necessary. Also, since the degree of superheat of the secondary refrigerant is large,
It is possible to prevent the refrigerant from remaining in the pipe at the time of recovery.

The separator (5) of the primary refrigerant circuit (40)
0) and an expansion valve (EV), an air-cooled condenser (4e) is provided to keep the primary refrigerant in front of the expansion valve (EV) in a liquid-sealed state at all times. As a result, the refrigerant does not pass through the expansion valve (EV) and does not run out of gas, so that the refrigerant charging amount can be reduced.

[0099]

Second Embodiment Next, a second embodiment of the present invention will be described.

The second embodiment shown in FIG.
The air-cooled condenser (4e) of the primary-side refrigerant circuit (40) is provided between the separator (50) and the expansion valve (EV) instead of the air-cooled condenser (4e). It is provided in the one-way passage (48) between (7A, 7B) and the separator (50), more specifically, between the rectifier circuit (47) and the separator (50).

In this case, the fan (4e) of the air-cooled condenser (4e)
f) is controlled so as to start when the high pressure on the primary side is equal to or higher than a predetermined value and to stop when the high pressure is equal to or lower than the predetermined value. For example, as in the first embodiment, when the high pressure on the primary side increases and reaches 18 kg / cm ² , the fan (4e) of the air-cooled condenser (4e)
f) is started, and when the pressure drops to 13 kg / cm ² , the fan (4f) of the air-cooled condenser (4e) is stopped.

In the second embodiment, the amount of the secondary refrigerant in the separator (50) is detected, and when the amount of the secondary refrigerant is smaller than a predetermined amount, the fan (4f) of the air-cooled condenser (4e) is detected. Is operated, and when it is larger than the predetermined amount, the fan (4f) is stopped. When the amount of the secondary refrigerant in the separator (50) is small, the amount of the primary refrigerant condensed in the separator (50) decreases, and the temperature of the separator (50) tends to increase. Can be lowered.

As described above, in the present embodiment, the separator (5
The temperature of 0) can be reduced. On the contrary,
If the temperature of the primary side of the separator (50) is high, the secondary side pressure will also be high, making it difficult for a high-low pressure difference with the transfer heat exchangers (7A, 7B) to be generated, and the secondary-side refrigerant will not be easily circulated. However, in the second embodiment, the refrigerant can be circulated smoothly and the circulation efficiency of the refrigerant can be further increased.

[0104]

Third Embodiment Next, a third embodiment of the present invention will be described.

In the third embodiment shown in FIG. 4, a bypass passage (49) for a separator (50) is provided in a refrigeration circuit (40) as a primary-side refrigerant circuit, and air cooling is different from that of the first and second embodiments. An air-cooled condenser (4e) is provided in the bypass passage (49) by changing the position of the condenser (4e).

In the present embodiment, the amount of the secondary refrigerant in the separator (50) is detected as in the second embodiment. And 1
When the amount of the secondary refrigerant in the separator (50) is smaller than the predetermined amount, the secondary refrigerant flows into the air-cooled condenser (4e) by bypassing the separator (50), and the fan of the condenser (4e) 4f) is started. When the amount of the secondary refrigerant in the separator (50) is larger than a predetermined amount, the primary refrigerant flows into the separator (50) so that the air-cooled condenser (4e) is not used.

In this case as well, since the temperature rise of the separator (50) can be prevented, the secondary-side refrigerant flows smoothly into the separator (50) as in Embodiment 2, and the secondary refrigerant is recovered. Rate can be increased.

[0108]

Other Embodiments of the Invention The present invention is not limited to the above embodiment, but may be implemented in other forms. For example, the air-cooled condenser (4e) provided in the upstream, downstream, or parallel position of the separator (50) in each of the above embodiments is not provided, and the primary-side discharged refrigerant is simply transferred to the transfer heat exchanger ( 7A, 7B). Even in this case, by increasing the temperature of the transfer heat exchangers (7A, 7B),
It is possible to increase the collection efficiency of the refrigerant.

A water-cooled condenser may be used instead of the air-cooled condenser (4e) used in each of the above embodiments. In this case, the same effects as in the above embodiments can be obtained by flowing the cooling water into the water-cooled condenser at the timing when the fan (4f) of the air-cooled condenser (4e) is started.

Further, in each of the above embodiments, the description has been given of the pipe washing and the refrigerant recovery. However, the refrigerant circulating apparatus of the present invention may perform only the refrigerant recovery. That is, the connection circuit (30) does not have to include the separator (50), and the connection circuit (30) may be connected to various refrigerant injection units.

Further, the pipe cleaning device (10) of each embodiment may function as a refrigerant regeneration device. That is, both ends of the connection circuit (30) in the second cleaning circuit (12) are connected to a container such as a refrigerant cylinder (91). And
The refrigerant filled in this container is used as a secondary refrigerant, and is circulated through the closed circuit (13) as in the cleaning operation. This circulation regenerates the refrigerant in the separator (50).

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram of a pipe cleaning device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing operating conditions of an air-cooled condenser provided in the pipe cleaning device of FIG.

FIG. 3 is a refrigerant circuit diagram of a pipe cleaning device according to a second embodiment of the present invention.

FIG. 4 is a refrigerant circuit diagram of a pipe cleaning device according to a third embodiment of the present invention.

[Explanation of symbols]

 (4e) Air-cooled condenser (4f) Fan (7A) Transfer heat exchanger (7B) Transfer heat exchanger (13) Closed circuit (secondary refrigerant circuit) (40) Refrigeration circuit (primary refrigerant circuit) (41 ) Compressor (49) Bypass passage (50) Separator (EV) Expansion valve

 ──────────────────────────────────────────────────の Continued on the front page (72) Masaaki Takegami 1304 Kanaokacho, Sakai City, Osaka Daikin Industries Inside the Kanaoka Plant of Sakai Seisakusho Co., Ltd. (72) Kazuhide Nomura 1304 Kanaokacho Sakai City, Osaka Daikin Industries Sakai Plant Kanaoka Factory

Claims (19)

[Claims] A refrigerant circulating device for pressurizing and circulating a secondary refrigerant in a secondary refrigerant circuit (13) in a primary refrigerant circuit (40) performing a vapor compression refrigeration cycle operation, comprising: 41) A refrigerant circulation device configured to directly supply the primary refrigerant discharged from 41) to the transfer heat exchangers (7A, 7B) that pressurize the secondary refrigerant. 2. The expansion mechanism (EV) of the primary refrigerant circuit (40).
An air-cooled condenser (4e) is connected to the upstream side of the air conditioner.
The refrigerant circulation device according to claim 1. 3. The primary refrigerant circuit (40) downstream of the transfer heat exchangers (7A, 7B) that pressurizes the secondary refrigerant, evaporates the secondary refrigerant by passing the primary refrigerant, and removes foreign matter. The refrigerant circulation according to claim 1, further comprising a separator (50) for removal, wherein an air-cooled condenser (4e) is connected between the separator (50) and an expansion mechanism (EV) downstream thereof. apparatus. 4. The air-cooled condenser (4e) has a fan (4f)
4. The refrigerant circulation device according to claim 2, wherein the refrigerant circulation device is configured to start when the high-pressure pressure of the secondary refrigerant circuit (40) becomes equal to or higher than a predetermined value, and to stop when the high pressure pressure becomes equal to or lower than the predetermined value. 5. The fan (4f) of the air-cooled condenser (4e) is configured to start when the primary refrigerant upstream of the expansion mechanism (EV) contains gas. 4. The refrigerant circulation device according to 3. 6. A primary refrigerant circuit (40) downstream of a transfer heat exchanger (7A, 7B) for pressurizing the secondary refrigerant, evaporates the secondary refrigerant by passing the primary refrigerant, and removes foreign matter. A separator (50) for removal is provided, and the transfer heat exchangers (7A, 7B) and the separator (5
The refrigerant circulation device according to claim 1, wherein an air-cooled condenser (4e) is connected between the refrigerant circulation device and the air-cooled condenser (4e). 7. The fan (4f) of the air-cooled condenser (4e) includes:
The refrigerant circulation device according to claim 6, wherein the refrigerant circulation device is configured to start when the high-pressure pressure of the secondary refrigerant circuit (40) is equal to or higher than a predetermined value and to stop when the high pressure is equal to or lower than the predetermined value. 8. The fan (4f) of the air-cooled condenser (4e) starts when the amount of the secondary refrigerant in the separator (50) is equal to or less than a predetermined amount, and stops when the amount of the secondary refrigerant is equal to or more than the predetermined amount. The refrigerant circulation device according to claim 6, wherein the refrigerant circulation device is configured. 9. A primary-side refrigerant circuit (40) downstream of a transfer heat exchanger (7A, 7B) for pressurizing the secondary refrigerant, evaporates the secondary refrigerant by passing the primary refrigerant, and removes foreign matter. A separator (50) for removal is provided, a bypass passage (49) for the separator (50) is provided, and an air-cooled condenser (4) is provided in the bypass passage (49).
The refrigerant circulation device according to claim 1, wherein e) is provided. 10. When the amount of the secondary refrigerant in the separator (50) is equal to or less than a predetermined amount, the primary refrigerant bypasses the separator (50) and flows through the air-cooled condenser (4e). 10. The system according to claim 9, wherein the fan (4f) of (4e) is started, and if the fan is more than a predetermined amount, the fan (4f) is circulated to the separator (50).
The refrigerant circulation device according to claim 1. 11. The expansion mechanism (E) of the primary refrigerant circuit (40).
The refrigerant circulation device according to claim 1, wherein a water-cooled condenser is connected upstream of V). 12. A primary refrigerant circuit (40) downstream of a transfer heat exchanger (7A, 7B) that pressurizes the secondary refrigerant, evaporates the secondary refrigerant by passing the primary refrigerant, and removes foreign matter. The refrigerant circulation device according to claim 1, further comprising a separator (50) to be removed, wherein a water-cooled condenser is connected between the separator (50) and an expansion mechanism (EV) on the downstream side thereof. 13. A water-cooled condenser, comprising: a primary-side refrigerant circuit (40);
13. The refrigerant circulation device according to claim 11, wherein the cooling water is circulated when the high-pressure pressure becomes equal to or higher than a predetermined value, and is stopped when the high-pressure pressure becomes equal to or lower than the predetermined value. 14. The refrigerant circulation according to claim 11, wherein the water-cooled condenser is configured so that cooling water flows when the primary refrigerant upstream of the expansion mechanism (EV) contains gas. apparatus. 15. A primary refrigerant circuit (40) downstream of a transfer heat exchanger (7A, 7B) that pressurizes the secondary refrigerant, evaporates the secondary refrigerant by passing the primary refrigerant, and removes foreign matter. A separator (50) for removal, wherein a water-cooled condenser is connected between the transfer heat exchangers (7A, 7B) and the separator (50).
The refrigerant circulation device according to claim 1. The water-cooled condenser includes a primary-side refrigerant circuit (40).
16. The refrigerant circulating device according to claim 15, wherein the cooling water circulates when the high-pressure pressure becomes equal to or higher than a predetermined value, and stops when the high-pressure pressure becomes equal to or lower than the predetermined value. 17. The water-cooled condenser has a structure in which the cooling water flows when the amount of the secondary refrigerant in the separator (50) is equal to or less than a predetermined amount, and stops when the amount of the secondary refrigerant is equal to or more than the predetermined amount. The refrigerant circulation device according to claim 15, which is configured. 18. A primary refrigerant circuit (40) downstream of a transfer heat exchanger (7A, 7B) for pressurizing the secondary refrigerant, evaporates the secondary refrigerant by passing the primary refrigerant, and removes foreign matter. The refrigerant circulation device according to claim 1, further comprising a separator (50) for removing, a bypass passage (49) for the separator (50), and a water-cooled condenser provided in the bypass passage (49). 19. When the amount of the secondary refrigerant in the separator (50) is equal to or less than a predetermined amount, the primary refrigerant bypasses the separator (50) and flows through the water-cooled condenser. 20. The refrigerant circulating apparatus according to claim 18, wherein the refrigerant is circulated and the primary refrigerant is circulated to the separator (50) when the amount is equal to or more than a predetermined amount.