JP3261585B1 - Refrigerant recovery device - Google Patents

Abstract

An object of the present invention is to provide a refrigerant recovery device which is inexpensive and compact, has high portability, is easy to operate, and can reduce the cost of recovering CFCs. SOLUTION: Fluorocarbon gas is sucked by a compressor 1, and the chlorofluorocarbon gas discharged from the compressor 1, whose pressure and temperature are increased, is supplied to a heat conversion means 2 to be a refrigerant liquid. The refrigerant recovery device is configured to collect the refrigerant gas in the refrigerant recovery tank 7 via the gas pipe 21 and suck the refrigerant gas in the refrigerant recovery tank 7 through the gas pipe 21. The heat conversion means 2 comprises a first-stage coil thin tube path 3 formed by coiling a small-diameter heat transfer tube, a large-diameter short tube 5 having a larger flow cross-sectional area than the heat transfer tube, and a first-stage coil thin tube. The solenoid valve in the liquid pipe 13 is constituted by a single row body or two or more multi-parallel bodies of heat conversion elements formed by connecting a second-stage coil capillary path 4 having a structure similar to the path 3 in series. 6 is controlled to open and close by a pressure detecting means 14 at an upper limit set value and to be closed by a lower limit set value, and the solenoid valve 22 in the gas pipe 21 is opened by the pressure detecting means 24 at an upper limit set value and at a lower limit set value. Open / close control is performed by closing the valve.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerant recovery apparatus for economically and efficiently recovering Freon gas, which is a main refrigerant used in air conditioners and other equipment for automobiles and houses.

[0002]

2. Description of the Related Art It is generally known that emission of chlorofluorocarbon gas into the atmosphere adversely affects the global environment. For this reason, in the case of disposing of an automobile as an example, it is widely used to recover CFCs from a refrigerant circuit in order to reuse CFCs without releasing them into the atmosphere.
Conventionally, a compressor and a condenser have been indispensable members of a recovery device in order to extract CFCs from a refrigerant system to be recovered and feed them to a recovery container such as a cylinder with a liquid.

[0003]

As described above, the conventional recovery apparatus is a large-scale facility because a cross-fin condenser, which is a large-sized heat exchanger, is required.
In addition, since the operating cost is high, it has been considered that the cost of recovering CFCs increases.

[0004] The present invention has been devised to solve the problems of the conventional refrigerant recovery apparatus.
Accordingly, it is an object of the present invention to provide a refrigerant recovery apparatus which is inexpensive and compact, has excellent portability, is easy to operate, and can reduce the cost of chlorofluorocarbon recovery.

[0005]

The present invention has the following configuration to achieve the above object. That is, the invention of claim 1 of the present invention, the CFCs to be recovered coolant gas sucked by the compressor 1 through the suction pipe 11, the refrigerant gas pressure and temperature discharged from the compressor 1 is increased, After supplying the heat liquid to the heat conversion means 2 having a function of converting heat energy to kinetic energy to make a refrigerant liquid, the refrigerant liquid is recovered to the refrigerant recovery tank 7 via the liquid pipe 13 in which the electromagnetic valve 6 is inserted. And a refrigerant recovery device in which the refrigerant gas in the refrigerant recovery tank 7 is sucked by the compressor 1 through a gas pipe 21 in which an electromagnetic valve 22 is interposed. , A first-stage coil narrow tube 3 formed by winding a coil, a large-diameter short tube 5 having a larger flow cross-sectional area than the heat transfer tube, and a second-stage coil similar in structure to the first-stage coil narrow tube 3 Heat conversion element formed by connecting capillary line 4 in series It is constituted by a multi-parallel body made of a single column, or two or more, the electromagnetic valve 6, a pressure detector 14 for detecting the outlet pressure of the second stage coil capillary passage 4 of the heat conversion means 2
The solenoid valve 22 is opened and closed at the upper limit set value and at the lower limit set value by the pressure detecting means 24 which detects the pressure in the refrigerant recovery tank 7 by opening and closing the valve at the upper limit set value and closing the valve at the lower limit set value. A refrigerant recovery device characterized in that opening and closing are controlled by closing a valve.

[0006] The invention of claim 2 in the present invention provides:
In the refrigerant recovery device according to claim 1, the refrigerant gas to be recovered is not prevented from being sucked into the compressor 1,
The suction pipe 11 is provided with a backflow preventing means 27 for preventing the recovered refrigerant gas in the refrigerant recovery tank 7 from flowing back to the recovered refrigerant gas introduction side via the gas pipe 21 and the suction pipe 11. Features.

[0007] The invention of claim 3 in the present invention provides:
3. The refrigerant recovery device according to claim 1, wherein a cooling fan 8 is attached to at least the first-stage coil narrow tube path 3 in the heat conversion element of the heat conversion unit 2, and the cooling fan 8 is discharged from the compressor 1. When the temperature of the refrigerant gas is equal to or higher than a predetermined value, the fan 8 is operated to blow air.

[0008] The invention of claim 4 in the present invention provides:
4. The refrigerant recovery apparatus according to claim 3, further comprising a cooling fan attached to the compressor, wherein the temperature of the refrigerant gas discharged from the compressor is equal to or higher than a predetermined value.
9 is configured to be operated by air blowing.

According to the present invention, since the heat conversion means 2, which is a member replacing the conventional condenser, has an extremely small and simple structure, the apparatus cost is low,
It is also suitable as a portable type.
Since the refrigerant recovery operation can be performed by controlling the opening and closing of the device, the operation is easy, and the device is very suitable as an inexpensive and low-cost recovery device.

Further, according to the present invention, the refrigerant recovery tank 7
The refrigerant gas in the tank is returned to the compressor 1 by the gas pipe 21 in which the solenoid valve 22 is inserted, and the pressure in the refrigerant recovery tank 7 is reduced, so that the refrigerant liquid filling amount in the refrigerant recovery tank 7 increases. In addition, the refrigerant recovery efficiency is improved.

Further, according to the invention of claim 2, the compressor 1
The backflow of the refrigerant gas returned to the chamber is reliably prevented, and a continuous refrigerant recovery operation under stable conditions is possible.

Further, according to the third aspect of the present invention, the heat conversion efficiency of the heat conversion means 2 is increased, the recovery efficiency is improved, and
The collection time can be shortened. According to the invention of claim 4, overheating of the compressor 1 is prevented and stable operation can be achieved.

The heat conversion means 2, which is the most important feature in the present invention, is designed to apply pressure energy to the refrigerant gas to be recovered discharged from the compressor 1, that is, during the compression stroke in the compressor 1. And the function of converting almost all of the thermal energy into kinetic energy for the refrigerant gas to be recovered, the pressure and temperature of which have been increased by the application of thermal energy, and effectively condensing the gas component in this conversion process. And the first in the heat conversion element.
In the stepped coiled conduit 3 and the second-staged coiled conduit 4, a rotating flow for converting kinetic energy is given to the refrigerant flowing inside and the flow velocity is increased, so that the gaseous component on the downstream side is reduced. On the other hand, in the large-diameter short pipe 5, the flash refrigerant of the gas-liquid mixture derived from the first-stage coil narrow pipe 3 is decelerated by the diffusion flow and the rotating flow is reduced. And has a function of further improving the rotation speed-up action and the condensation / liquefaction action in the subsequent second-stage coil narrow pipe 4, and thus has a large structure as in the conventional condenser It is possible to reliably condense and liquefy the refrigerant gas by this small-sized heat conversion means 2 without relying entirely on the heat exchange action of the heat exchanger. The is where the present inventors or the like is confirmed sufficiently on the basis of a result of extensive studies and experiments, also, is to be revealed by the description of embodiments of the invention described below.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a circuit diagram schematically illustrating a refrigerant recovery device according to a first embodiment of the present invention. FIG. 2 is a perspective view of the heat conversion means 2 in the refrigerant recovery device shown in FIG.

The refrigerant recovery device shown in FIG.
A heat conversion means 2, an electromagnetic valve 6, and a refrigerant recovery tank 7 are provided as elemental devices, and these devices are provided with a suction pipe 11, a discharge pipe 1,
By connecting the refrigerant pipes 2 and the liquid pipe 13 as a series circuit, a device for efficiently recovering Freon gas as a refrigerant is constituted.

Further, the refrigerant recovery device includes a gas pipe 21 in which an electromagnetic valve 22 is inserted as a bypass to the series circuit, and compresses the refrigerant gas in the refrigerant recovery tank 7 through the gas pipe 21. A gas return circuit for suction by the machine 1 is additionally provided.

A tube pursing valve provided for extracting Freon gas contained in, for example, an air conditioner refrigerant circuit of an automobile, which is an inlet 9 serving as a refrigerant collection part, and a suction port of the compressor 1 are connected to a cock 16. , An acid removing filter 25, a filter dryer 10 and a check valve 27 realized by a check valve are connected by a suction pipe 11 interposed in series, and the discharge port of the compressor 1 and the heat conversion means 2 are connected. Of the heat conversion means 2 and the inlet of the refrigerant recovery tank 7 are connected to the electromagnetic valve 6 and the cock. 17 are connected by a liquid pipe 13 interposed in a series relationship, thereby forming the series circuit of the CFC recovery device. The cocks 16 and 1
A check valve may be used instead of 7.

On the other hand, the gas pipe 21 in which the solenoid valve 22 is inserted
A gas outlet 31 protruding from the top wall of the refrigerant recovery tank 7.
A gas return circuit is provided in the device circuit by arranging the gas supply circuit so as to extend between the suction pipe 11 and a portion near the suction port of the compressor 1. A cock 23 and an electromagnetic valve 22 are interposed in the gas pipe 21 in series from the refrigerant recovery tank 7 side.

In FIG. 1, reference numerals 18 and 19 denote sight glasses provided in the middle of the suction pipe 11 and the liquid pipe 13, respectively. It is provided as needed for observation from the side.

The heat conversion means 2 comprises a first-stage coil thin tube path 3 formed by winding a small-diameter heat transfer tube, for example, a copper thin tube, for example, in a left coil winding with reference to the flow direction of the refrigerant in the pipe line. ,
A short tube 5 made of, for example, a copper tube having a large cross-sectional area larger than that of the heat transfer tube and made of, for example, a copper tube, and a second-stage coil narrow tube 4 having a structure similar to the first-stage coil narrow tube 3 are formed. It is a refrigerant flow conduit composed of heat conversion elements formed by connecting in series in the stated order from the upper side to the lower side based on the flowing direction of the flowing Freon. The conversion means 2 is configured, and the inner diameter of the first-stage coil thin tube 3 and the second-stage coil thin tube 4 is 0.8 to 3.2.
a coil tube formed by coiling a copper thin tube having a predetermined diameter in a range of mmφ and a predetermined length in a range of 1.0 to 3.0 m into a spiral having a predetermined diameter in a range of 20 to 50 mmφ. ing. It should be noted that the first-stage coil thin-tube path 3 is housed in an elongated cylindrical casing shown by a dashed line in FIG. 2 so that air can be blown into the casing by an attached fan 8 so as to be forcibly cooled. Has formed.

On the other hand, the large-diameter short pipe 5 has a diameter of 12.
A copper short tube having a length of 7 mm (1/2 in) and a length of several tens of mm is used, and both ends thereof are finished to a small diameter by drawing or the like. The outflow side end of the capillary tube 3 is connected, and the inflow side end of the second-stage coil capillary tube 4 is connected to the outflow side end.

However, the first-stage coil thin line 3 and the second-stage coil thin line 4 may have the same structure.
The pipe length and the pipe diameter may be made different.
The coil winding direction may be the same, or one may be left-handed and the other right-handed.

The check valve as the check valve 27 is
As shown in the drawing, the suction pipe 11 is interposed at a position closer to the sight glass 18 with respect to the branch connection point of the gas pipe 21, the blocking port is on the branch connection point side, and the forward flow port is on the sight glass 18 side. And the suction pipe 11
Provided inside.

The check valve 27 provided in this manner does not impede the flow of the refrigerant gas to be recovered which flows into the suction pipe 11 from the inlet 9 and is sucked into the compressor 1 without any problem.
On the other hand, even if the recovered refrigerant gas flowing out of the refrigerant recovery tank 7 and flowing through the gas pipe 21 and the suction pipe 11 tries to flow back to the inlet 9 on the side of the refrigerant gas to be recovered, this reverse flow can be reliably prevented. Needless to say,

In FIG. 1, reference numerals 14 and 24 denote pressure detecting means, 15
Is a temperature-sensitive cylinder, and the pressure detecting means 14 is provided for detecting the pressure in the liquid pipe 13 and detects the outlet pressure of the second-stage coil narrow pipe 4 to efficiently perform the liquefaction of the CFC gas. The upper limit set value in the optimal pressure range, for example, in the case of Freon R-12, 8 kg / cm ² or more, the valve opening output to the solenoid valve 6, and the lower limit set value, for example, 5 kg / cm ² or less, also the valve output. Solenoid valve 6
, While the pressure detecting means 24 is associated with the solenoid valve 22 in relation to the gas pipe 21 at a location near the refrigerant recovery tank 7 in order to detect the pressure in the refrigerant recovery tank 7. The upper limit set value in an optimum pressure range for stably and sufficiently filling the chlorofluorocarbon liquid in the refrigerant recovery tank 7, for example, 8 kg / cm ² or more in the case of chlorofluorocarbon R-12. To the solenoid valve 22 to output a lower limit set value, for example, 5 kg /
It is provided as an opening / closing control member for the electromagnetic valve 22 so as to similarly generate a valve closing output at cm ² or less. On the other hand, the temperature-sensitive cylinder 15 is provided for detecting the temperature of the discharge pipe 12, and is configured to output a blowing operation output to the fan 8 when the temperature of the Freon gas discharged from the compressor 1 is equal to or higher than a predetermined value. As a drive control member.

In the refrigerant recovery apparatus shown in FIG. 1, the refrigerant recovery tank 7 is provided with an overfilling prevention sensor 28 comprising, for example, a liquid level detector so that the amount of the recovered refrigerant liquid in the refrigerant recovery tank 7 is controlled to a predetermined value. When the filling amount is reached, a stop output is issued to the compressor motor 29 to stop the compressor 1.

Next, the operation of the refrigerant recovery device will be described. As the compressor 1, a reciprocating compressor having an output of 150 Watt is used.
A first-stage coil narrow tube path 3 formed by spirally winding a 5 mmφ, 1.5 m long copper tube to the left with a coil having a coil diameter of 25 mmφ, and a 1.2 mm long copper tube having an inner diameter of 1.5 mmφ with a coil diameter of 2 mm
A single row body of heat conversion elements consisting of a second-stage coil narrow tube 4 formed by helically winding the left coil into a 5 mmφ spiral and a large-diameter short tube 5 formed of a copper short tube having a diameter of 12.7 mm and a length of 10 mm was prepared. The operation of recovering Freon R-12 will now be described.

The CFC gas extracted in the inlet 9 by the operation of the compressor 1 passes through the cock 16, and after the impurities and moisture are removed by the filter / dryer 10 and the acid content is removed by the acid removal filter 25, the compression is performed. Inhaled by machine 1. The pressure and temperature of the chlorofluorocarbon gas generated by the compression of the compressor 1 are increased by the oil separator 26 and then sent to the heat conversion means 2 after the oil content is removed. Is converted into kinetic energy by the flow velocity increasing phenomenon accompanied by the flow, and after being condensed and liquefied, supplied through the electromagnetic valve 6 and the cock 17 to the refrigerant recovery tank 7 composed of a pressure cylinder as Freon liquid. You.

In this case, as described above, the solenoid valve 6 is opened when the outlet pressure of the heat conversion means 2 is 8 kg / cm ² or more and 5 k
The opening and closing were controlled so as to close the valve at g / cm ² or less. As a result, small bubbles were slightly confirmed in the sight glass 18, while the flow of the transparent liquid was confirmed in the sight glass 19 while the solenoid valve 6 was opened, and the refrigerant recovery in which the Freon R-12 flows in a continuous liquid state was performed. It was recognized that driving was running smoothly. The temperature of the discharge pipe 12 is set to a set value, for example, 60.
When the temperature reaches °, the fan 8 is operated to blow air, and the pressure in the suction pipe 11 becomes zero, so that the operation of the compressor 1 is stopped assuming that the Freon recovery is completed.

However, during the refrigerant recovery operation by the heat conversion means 2, the pressure in the tank is set to the upper limit value, for example, 8 kg, even though the recovered refrigerant liquid amount in the refrigerant recovery tank 7 is small and there is a margin before full filling. / Cm ² , the solenoid valve 22 is opened because the pressure detecting means 24 outputs a valve opening output to the solenoid valve 22 as described above. This allows
The refrigerant gas filling the refrigerant recovery tank 7 flows out of the gas outlet 31, passes through the gas pipe 21, reaches the suction port of the compressor 1, merges with the refrigerant gas to be recovered flowing through the suction pipe 11, and After being sucked into 1, the refrigerant recovery operation by the heat conversion means 2 as described above is performed again. At that time, check valve 27
Flows from the inlet 9 into the suction pipe 11 and
Without obstructing the flow of the refrigerant gas to be recovered sucked in at all. On the other hand, it is ensured that the recovered refrigerant gas which has passed through the gas pipe 21 and the suction pipe 11 tends to flow back to the inlet 9 on the side of the refrigerant gas to be recovered. Needless to say, it will be stopped.

Due to the outflow of the refrigerant gas from the gas pipe 21, the pressure in the refrigerant recovery tank 7 is reduced to a lower limit set value, for example, 5 kg /
cm ² or less, the pressure detecting means 24
The solenoid valve 22 is closed to generate a valve closing output. Thereby, the operation of returning the refrigerant gas to the compressor 1 side is stopped, and the refrigerant recovery operation by the heat conversion means 2 is continuously performed.

By continuing the operation of returning the refrigerant gas to the compressor 1 side, the pressure in the refrigerant recovery tank 7 is maintained at an appropriate value. As a result, a sufficient amount of refrigerant is recovered in the refrigerant recovery tank 7. The refrigerant liquid is filled. In this case, due to the operation of the overfill prevention sensor 28, when the amount of the recovered refrigerant liquid in the refrigerant recovery tank 7 reaches a predetermined amount, a stop output is issued to the compressor motor 29 and the compressor 1 is stopped as described above. . Thus, a refrigerant recovery operation with high charging efficiency is realized.

FIG. 3 is a circuit diagram schematically showing a refrigerant recovery apparatus according to a second embodiment of the present invention. In the refrigerant recovery device shown in FIG. 3, similar to the refrigerant recovery device according to the first embodiment,
The same reference numerals are given, and the detailed description of the individual element members will be omitted to avoid duplication.

The refrigerant recovery apparatus according to the second embodiment is characterized in that it is characterized in terms of structure as compared with the refrigerant recovery apparatus according to the first embodiment.
Is a multi-parallel body of two or more heat conversion elements formed by connecting the first-stage coil capillary 3, the large-diameter short pipe 5, and the second-stage coil capillary 4 in series (in the case of the present embodiment). Are arranged in a three-parallel body), each of the first-stage coil narrow pipes 3 is forcibly cooled by a fan 8, and the compressor 1 is provided with a cooling fan 29. And each point.

That is, the refrigerant recovery apparatus according to the embodiment of the present invention shown in FIG. 3 has a heat conversion system comprising a first-stage coil narrow tube 3, a large-diameter short tube 5, and a second-stage coil narrow tube 4. The heat conversion means 2 is constituted by connecting three elements having the same structure in parallel as shown in the figure, and this is inserted and connected between the discharge pipe 12 and the liquid pipe 13. Also, the discharge pipe 1
When the temperature of the fluorocarbon gas discharged from the compressor 1 is equal to or higher than a predetermined value, a blow operation output is issued to the fan 8 based on a command from the temperature sensing cylinder 15 provided for detecting the temperature of the fan 2 to perform heat conversion. The means 2 is forcibly cooled. Further, a cooling fan 29 is attached to the compressor 1 so that when the temperature of the CFC gas discharged from the compressor 1 is equal to or higher than a predetermined value, the fan 29 is cooled. 8 and the air blowing operation.

However, in the refrigerant recovery apparatus according to the present invention, in order to obtain a liquefaction and recovery capacity corresponding to the compression capacity of the compressor, the refrigerant gas condensing / liquefaction capacity of the heat conversion means 2 must be increased. Naturally, it must be maintained at an appropriate capacity corresponding to that. Therefore, when it is expected that the capacity of the heat conversion means 2 which is a single row of heat conversion elements is insufficient, the compression capacity of the compressor is reduced. Depending on two parallel,
By employing a multi-parallel system of three or more, it is possible to increase the capacity of the heat conversion means 2. From this point, the refrigerant recovery device of the present embodiment shown in FIG. 3 is of a three-parallel type, so that the heat conversion means 2 capable of maintaining the refrigerant gas condensation / liquefaction capability balanced with the compression capability of the compressor 1. As a result, it is possible to perform a liquid refrigerant recovery operation that can achieve high efficiency and reduce time.

The refrigerant recovery device of the present embodiment shown in FIG. 3 operates in conjunction with the fan 8 when the temperature of the Freon gas discharged from the compressor 1 is higher than a predetermined value.
, The compressor 1 is protected from overheating, and a safe and stable liquid refrigerant recovery operation is realized.

FIG. 4 is a temperature characteristic diagram showing a temperature transition of each part during the refrigerant recovery operation of the refrigerant recovery device according to the second embodiment of the present invention. FIG. 5 is an integrated recovery amount diagram showing a change in the refrigerant recovery operation performance in the refrigerant recovery device according to the second embodiment of the present invention.

The measurement results shown in FIGS. 4 and 5 indicate that a reciprocating compressor having an output of 150 Watt was used for the compressor 1 and that the heat conversion means 2 had an inner diameter of 1.5 mmφ and a length of 1.5 m. Is formed by winding a copper tube spirally with a coil diameter of 25 mmφ to the left and forming a first-stage coiled narrow tube path 3.
A second-stage coiled narrow tube path 4 formed by spirally winding a 5 mmφ, 1.2 m long copper tube to the left with a coil having a coil diameter of 25 mmφ.
And a recovery operation of Freon R-22 using a three-parallel body of heat conversion elements composed of large-diameter short pipes 5 formed of copper short pipes having a diameter of 12.7 mm and a length of 10 mm.

In FIG. 4, line A is a temperature transition line at the outlet of the collection container filled with Freon R-22 gas as the refrigerant collection portion, and line B is a temperature transition line of the suction pipe 11. , Line C represents the temperature transition line of the discharge pipe 12, line D represents the temperature transition line of the outlet pipe of the heat conversion means 2, and line E represents the temperature transition line in the refrigerant recovery tank 7.

Referring to FIG. 4, the temperature of the gas discharged from compressor 1 is about 52 ° C., and the temperature of the liquid refrigerant on the outlet side of heat conversion means 2 is 32 ° C.
5 ° C. and the temperature in the refrigerant recovery tank 7 are constant at approximately 30 ° C., respectively, and a smooth and stable refrigerant recovery operation is performed. In addition, referring to FIG. It shows that 1000 g of Freon R-22 is recovered stably under operation.

[0042]

The present invention is embodied in the form described above and has the following effects. That is, according to the present invention, the refrigerant liquefied by the heat conversion means 2 can be efficiently and smoothly supplied to the refrigerant recovery tank 7, and the refrigerant recovery can be performed simply and easily. Further, according to the apparatus of the present invention, which includes the heat conversion means 2 as a constituent element, it is inexpensive and compact, has excellent portability, is easy to operate, and can reduce the cost of chlorofluorocarbon recovery.

Further, according to the present invention, the refrigerant recovery tank 7
The refrigerant gas in the tank is returned to the compressor 1 by the gas pipe 21 in which the solenoid valve 22 is inserted, and the pressure in the refrigerant recovery tank 7 is reduced, so that the refrigerant liquid filling amount in the refrigerant recovery tank 7 increases. In addition, the refrigerant recovery efficiency is improved.

According to the second aspect of the present invention, the compressor 1
The backflow of the refrigerant gas returning to the step is prevented, and the continuous refrigerant recovery operation is performed under a stable condition.

Further, according to the third aspect of the present invention, the heat conversion efficiency of the heat conversion means 2 is increased, the recovery efficiency is improved, and
The collection time can be shortened. Furthermore, according to the invention of claim 4, overheating of the compressor 1 is prevented and safety is excellent.

[Brief description of the drawings]

FIG. 1 is a circuit diagram schematically showing a refrigerant recovery device according to a first embodiment of the present invention.

FIG. 2 is a heat conversion means 2 in the refrigerant recovery device shown in FIG.
It is a perspective view of.

FIG. 3 is a circuit diagram schematically illustrating a refrigerant recovery device according to a second embodiment of the present invention.

FIG. 4 is a temperature characteristic diagram showing a temperature transition of each part during a refrigerant recovery operation of the refrigerant recovery device according to the embodiment of the present invention.

FIG. 5 is an integrated recovery amount diagram showing transition of refrigerant recovery operation performance in the refrigerant recovery device according to the embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Compressor 2 ... Heat conversion means 3
... First-stage coil capillary 4. Second-stage coil capillary 5. Large-diameter short tube 6
… Solenoid valve 7… Refrigerant recovery tank 8… Fan 9
... Inlet 10 ... Filter / dryer 11 ... Suction pipe 1
2 ... discharge pipe 13 ... liquid pipe 14 ... pressure detection means 1
5 ... temperature sensing tube 16 ... cock 17 ... cook 1
8 Sight glass 19 Sight glass 20 Fan 2
DESCRIPTION OF SYMBOLS 1 ... Gas pipe 22 ... Solenoid valve 23 ... Cock 2
4 ... Pressure detecting means 25 ... Acid removal filter 26 ... Oil separator 2
7: Backflow prevention means 28: Overfill prevention sensor 29: Compressor motor 3
1. Gas outlet 32 ... Refrigerant strainer

Claims (4)

(57) [Claims] 1. A the CFCs to be recovered coolant gas sucked by the suction pipe 11 compressor 1 through the conversion of the refrigerant gas pressure and temperature discharged from the compressor 1 is increased, the thermal energy into kinetic energy After supplying the refrigerant liquid to the heat conversion means 2 having a function of performing a cooling operation, the refrigerant liquid is recovered to the refrigerant recovery tank 7 via the liquid pipe 13 in which the solenoid valve 6 is inserted. A refrigerant recovery device in which refrigerant gas is sucked by a compressor 1 through a gas pipe 21 in which an electromagnetic valve 22 is inserted, wherein a heat conversion unit 2 is formed by coiling a small-diameter heat transfer tube. The first-stage coil thin tube 3, a large-diameter short tube 5 having a larger flow cross-sectional area than the heat transfer tube, and the second-stage coil thin tube 4 having a structure similar to the first-stage coil thin tube 3 are connected in series. From a single row or two or more heat conversion elements formed by connecting The solenoid valve 6 is opened by the upper limit set value and closed by the lower limit set value by the pressure detecting means 14 for detecting the outlet pressure of the second-stage coil narrow pipe 4 of the heat conversion means 2. Opening / closing control is performed, and the solenoid valve 22
Pressure detecting means 24 for detecting the pressure in the refrigerant recovery tank 7
The refrigerant recovery device is characterized in that the valve is controlled to open and close at a set upper limit value and to close at a lower limit set value. 2. The collected refrigerant gas in the refrigerant recovery tank 7 passes through the gas pipe 21 and the suction pipe 11 to the collected refrigerant gas introduction side without preventing the refrigerant gas to be recovered from being sucked into the compressor 1. 3. The refrigerant recovery device according to claim 2, wherein a backflow prevention means for preventing backflow is provided in the suction pipe. 3. A cooling fan 8 is attached to at least the first-stage coil narrow pipe 3 in the heat conversion element of the heat conversion means 2, and the temperature of the refrigerant gas discharged from the compressor 1 is equal to or higher than a predetermined value. The refrigerant recovery device according to claim 1 or 2, wherein the fan (8) performs a blowing operation at the time of (1). 4. The compressor 1 further comprises a cooling fan 29 attached thereto, and when the temperature of the refrigerant gas discharged from the compressor 1 is equal to or higher than a predetermined value, the fan 29 performs a blowing operation. Refrigerant recovery device.