JPH0727450A - Pressure control mechanism and pressure control method in bleeder of refrigerator - Google Patents

Abstract

(57) [Summary] [Purpose] An unknown prior application (Japanese Patent Application No. 4-181035)
The bleeding technology according to (1) is further improved to control the pressure distribution in the bleeding system and prevent the backflow of the mixed gas (refrigerant gas + non-condensable gas). [Composition] A bypass line By is provided in the compressor 12, and a second electromagnetic valve 51 and an orifice 52 are provided therein so that the suction side In of the compressor 12 can be operated even during idling operation (bypass operation). Keep the pressure proper. The second solenoid valve 51 is controlled by the automatic controller 61 so that the first solenoid valve 15
Is opened when is closed. The third electromagnetic valve 53 and the auxiliary orifice 54 assist the above-mentioned pressure control and finely control according to the pressure in the rectifier 9 or the pressure on the suction side In.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste gas such as a refrigerant gas, which is circulated in accordance with a refrigerating cycle of evaporation → compression → condensation → decompression → (evaporation) like a refrigerator, for example. -A method for controlling a pressure distribution in a bleeder for extracting a harmful mixed gas (hereinafter, referred to as a non-condensable gas) and discharging it into the atmosphere, and a method suitable for carrying out the above-mentioned invention method. It relates to the configured device.

[0002]

2. Description of the Related Art FIG. 6 is a system diagram schematically showing a refrigerator equipped with a conventional air extraction device. The refrigerant gas in the refrigerator 1 is pressurized by the compressor 1c, deprived of heat by the condenser 1a and liquefied, deprived of heat by the evaporator 1b and vaporized, and this refrigeration cycle is continuously repeated. If a non-condensable gas is mixed with the above-mentioned refrigerant gas, the efficiency of the refrigeration system may be reduced or the components of the refrigerator may be corroded. Therefore, the non-condensable gas is removed from the refrigerant gas in the refrigerator 1. It needs to be eliminated. Since the non-condensable gas is generally lighter than the refrigerant gas, it accumulates in the condenser 1a in a state of being mixed with the refrigerant gas. The mixed gas is pressurized by the compressor 2, cooled by the cooler 3 and guided to the gas-liquid separated gas (abbreviated separator) 4. The refrigerant that has been cooled and condensed by the cooler 3 collects at the bottom of the separator 4 and returns to the evaporator 1b of the refrigerator 1 via the float valve 7. Since the non-condensable gas and the uncondensed refrigerant gas in the mixed gas are stored in the separator 4, the pressure thereof gradually rises. The pressure in the separator 4 is detected by the pressure sensor 5,
When the predetermined pressure is reached, the discharge unit 6 operates and the gas in the separator 4 is discharged into the atmosphere.

FIG. 7 shows a conventional example different from that shown in FIG.
In this conventional example, the separator 4 is provided with a cooling jacket 8, and the liquid refrigerant in the condenser 1a of the refrigerator 1 is introduced into the cooling jacket 8 to be vaporized in the jacket and returned to the evaporator 1b. Then, the heat of vaporization is removed to cool the separator 4. 21 is an orifice. In this type of conventional example, the compressor 2 shown in the conventional example (FIG. 6) is omitted, and the operation of the cooler 3 is performed by the jacket 8. Since the inside of the separator 4 is cooled to a temperature lower than that of the condenser 1a by the jacket 8, the pressure inside the separator 4 becomes lower than that of the condenser 1a, and the mixed gas (leakable non-condensable gas inside the condenser 4) A mixed gas of gas and refrigerant gas) flows into the separator 4. The inside of the separator 4 in the conventional example of FIG. 7 is usually cooled to a temperature lower than that of the conventional example of FIG. 6 (for example, 10 to 20 ° C.). However, even if the mixed gas in which the non-condensable gas is mixed in the refrigerant gas in the refrigerator 1 is cooled by the jacket 8, not all of the refrigerant gas in the mixed gas is liquefied, and the refrigerant gas from the discharge unit 6 is released into the atmosphere. The refrigerant gas is contained in the released non-condensable gas.

For example, a refrigerator with a capacity of 300RT (1RT is 3024 kcal / hour) stores about 500 kg of refrigerant, but the amount is reduced by 10 to 15% per year. It is inferred that a considerable part of this weight loss was released into the atmosphere along with the non-condensable gas during extraction. Although it is economically inconvenient for the refrigerant gas to be diffused into the atmosphere in this way, it cannot be left as it causes ozone layer destruction. In order to remarkably reduce the accompanying discharge of the refrigerant gas described above, the gas accumulated in the separator 4 is not directly discharged into the atmosphere but a rectifier (a separator having a strong refrigeration function). ) And liquefying the mixed refrigerant gas to liquefy the mixed gas, and then it is effective to perform more accurate fractionation (rectification) and then release it into the atmosphere. This technology was created by the present inventors and is a patent application that has not been published yet (Japanese Patent Application No.
No. 181035). Hereinafter, this is called the invention of the prior application.

FIG. 8 shows an embodiment of the extraction device according to the invention of the prior application. This embodiment is an improvement made by applying the invention of the prior application to the conventional example of FIG. 7, and the constituent parts (the left half part of this FIG. 8) designated by the same reference numerals as in FIG. It is similar to or similar to that in the conventional example. The gas stored in the upper space in the separator 4 is guided to the rectifier 9 via the solenoid valve 15 without directly releasing it into the atmosphere. The compressor 12 and the dryer 13 shown by phantom lines will be described later.
The rectifier 9 has a built-in cooling pipe 9a, and a cold heat source 10
From the cold fluid stream 10a. Cold heat source 1 above
Reference numeral 0 denotes a compressor 10b and a cooler 10c, which is connected to the cooling pipe 9a to form a closed circuit, and constitutes one set of small refrigerators.

The gas introduced into the rectifier 9 is a non-condensable gas containing a small amount of refrigerant gas, but it was contained when it was cooled by touching the cooling pipe 9a in the rectifier 9. The refrigerant gas is liquefied and collected at the bottom of the rectification tank 9. The liquefied refrigerant liquid is recovered in the refrigeration system of the refrigerator 1 through the float valve 9d. In this way, the refrigerant gas is almost completely removed, and the substantially pure non-condensable gas is stored in the upper space of the rectifier 9, and the pressure gradually increases. When the detection signal value of the pressure sensor 9b exceeds a predetermined value, the discharge valve 9
c is opened and released into the atmosphere.

In the embodiment of the invention of the prior application (FIG. 8), a dryer 13 or a dryer 13 'shown by a virtual line is provided,
By removing the water vapor in the gas sent from the separator 4 to the rectifier 9, there is no concern that the water vapor contained in the non-condensable gas will frost inside the rectifier 9. When frost is generated in the rectifier, it is inconvenient because it hinders the operation of the valves and the heat conduction of the cooling pipe 9a. Therefore, it is necessary to prevent the formation of frost by providing the dryer 13 or 13 '. The operational reliability of the invention device according to claim 1 is improved. Also, the separator 4 and the rectifier 9
When the compressor 12 shown by the phantom line is provided in the pipeline connecting the and, the non-condensable gas in the rectifier 9 is compressed to have a high density, and in the mixed gas of the non-condensable gas and the refrigerant gas. The mixture ratio of the refrigerant gas can be reduced and the discharge of the refrigerant gas can be suppressed. The compressor 12 described with reference to FIG. 8 is closely related to the problem to be solved by the present invention, which will be described later.
Since the dryer 13 or 13 'has little relation to the problem to be solved, it is shown by a virtual line in this figure.

As described above with reference to the system diagram of FIG. 8, since the invention of the prior application performs the crude distillation by the separator 4 and the refinement distillation by the rectifier 9 in series, the separator 4 is the original. The effect of the refinement distillation by the rectifier 9 is exhibited on the assumption that the purpose (crude distillation) is fulfilled. Therefore, it is not preferable for the mixed gas to pass through the separator 4. From this point of view, it is desirable to provide the electromagnetic valve 14 in the mixed gas inflow conduit of the separator 4 and close the electromagnetic valve 14 when opening the electromagnetic valve 15. As a result, the mixed gas does not pass through the separator 4 and the rectifier 9 completely performs the intended function.

[0009]

The bleeding apparatus of the invention according to the prior application shown in FIG. 8 does not directly release the mixed gas from the separator 4 into the atmosphere, but the mixed gas in the separator 4 is discharged. To the rectifier 9 for strong cooling, and the compressor 12 pressurizes the mixed gas. The content rate of the refrigerant gas in the mixed gas is determined by the temperature-pressure, and the content rate becomes low at low temperature and high pressure. The inventors of the present invention have confirmed that the intended purpose of reducing the content rate of the refrigerant gas released along with the extraction apparatus having the configuration of FIG. 8 has been practically used, and there is room for improvement as described below. I also confirmed that there is.
The bleeding operation is performed while continuing the operation of the refrigerator 1, and when the pressure sensor 5 detects that the pressure inside the separator 4 has risen to a predetermined value, the solenoid valve 15 is opened and the inside of the separator 4 is opened. When the pressure drops, the solenoid valve 15 is closed. This opening / closing frequency varies depending on the amount of non-condensable gas mixed in the refrigerant in the refrigerator and other operating conditions, but generally the valve opening time is very short, for example 5 seconds, and the valve closing time is It is relatively long, for example 2 minutes. However, relatively long means that it is longer than the valve opening time, and one cycle of opening and closing is more than 2 minutes. For this reason, while the electromagnetic valve 15 is closed, the compressor 12 is in a high vacuum state with its suction side closed, which causes a problem such as impairing the sealing function of the shaft sealing device of the compressor. As a practical matter, the safety device built in the compressor 12 is activated and automatically stopped, and the operation is automatically restarted when the solenoid valve 15 is opened. As a result, the compressor 12 is frequently started and stopped every few minutes. Such repeated start and stop of the compressor 12 in a short cycle causes problems concerning refueling of the compressor 12 and problems regarding the drive means. That is, if the electric motor driving the compressor 12 is repeatedly rotated and stopped frequently, not only the coil of the electric motor is burned but also fluctuations in the power supply voltage may occur, which may adversely affect neighboring devices. There is These technical problems are caused by applying the invention of the prior application to a bleeder equipped with a thermal purge type separator 4 equipped with a cooling means (for example, a cooling jacket 8) by applying a rectifier 9, a compressor 12, a cold heat source. This occurs when 10 is provided.

The present invention has been made in view of the above circumstances, and includes a rectifier (9) for strongly cooling a mixed gas to reduce the content rate of a refrigerant gas, and a gas in the rectifier. A compressor that increases the pressure to relatively reduce the partial pressure of the refrigerant gas (1
2) is applied to the extraction device, the first purpose of which is
It is an object of the present invention to provide a technique for opening and closing the solenoid valve (15) without frequently starting and stopping the compressor (12) and without causing a problem such as early wear of the compressor (12). .

A second object is to provide a technique for eliminating the possibility that the pressure balance near the separator (4) will be lost due to the opening and closing of the solenoid valve 15 and a backflow of gas will occur. . This second object relates to the solution of the problems associated with the means for achieving said first object.
In order to achieve the first and second objects, the present invention provides a new solenoid valve in addition to the solenoid valve (15). Therefore, in order to distinguish it from the solenoid valve (15), Called the solenoid valve.

[0012]

In order to achieve the above-mentioned object (protecting a compressor in a bleeder equipped with a rectifier), a first aspect of the present invention relates to a non-condensable gas leaking into a refrigerator. The mixed gas with the refrigerant gas is extracted and guided to the separator (4), and is cooled to liquefy a part of the refrigerant gas and recirculate it to the refrigerator, and the remaining mixed gas is compressed to the compressor ( Pressurize with 12), chill with rectifier (9),
Extraction gas that liquefies a part of the refrigerant gas in the remaining gas and discharges the gas in the rectifier from the discharge unit (9c) to the atmosphere when the gas pressure in the rectifier reaches a predetermined pressure. In the device, the separator (4) and the compressor (12)
A first solenoid valve (15) is provided between the first and second valves, and a bypass conduit (By) that connects the suction side and the discharge side of the compressor (12) is provided, and a second conduit is provided in the bypass conduit. The electromagnetic valve (51) is inserted and connected, and the automatic controller (61) controls the opening and closing of the first and second electromagnetic valves in an interlocking manner, and when the first electromagnetic valve is closed, the second electromagnetic valve is opened. A solenoid valve is opened to protect the compressor (12).

A second aspect of the present invention is to provide a means for suppressing a flow rate in the bypass pipe line in series with the second solenoid valve (51) in the bypass pipe line (By). Second
Even when the solenoid valve is opened, the differential pressure is generated in the bypass pipe line, and the pressure difference is higher than the pressure in the separator (4) connected to the suction side of the compressor (12). It is characterized in that the pressure on the suction side of the compressor is kept low.

[0014]

According to the first aspect of the invention, when the first solenoid valve is closed, the second solenoid valve is opened and the bypass pipe line of the compressor is communicated, so that the compressor is continuously operated. However, the suction side does not have a closed shape, and there is no possibility of causing a trouble in driving or activating the safety device. When the first solenoid valve is opened, the second solenoid valve is closed and the bypass line is closed. When the bypass pipeline is closed, it becomes equivalent to a state in which the bypass pipeline is not provided, the compressor performs its original function, and the pressure of the mixed gas in the rectifier is increased to increase the refrigerant gas. The partial pressure is relatively reduced, and the content rate of the accompanying refrigerant gas is reduced.

The second invention is also used in combination with the first invention, and appropriately adjusts the flow resistance of the bypass pipe in a state where the second solenoid valve is opened so that the discharge side of the compressor is The pressure difference between the suction side is automatically maintained at an appropriate value to control the pressure distribution in the vicinity of the separator, and in particular, there is no risk of the mixed gas flowing backward when the first solenoid valve is opened.

[0016]

FIG. 5 is a system diagram of a pressure control mechanism according to the first invention. The first invention is shown in the system diagram of FIG. 8 which is an embodiment of the invention of the prior application (Japanese Patent Application No. 4-181035). Is an example improved by applying. Next, differences from FIG. 8, that is, matters improved by applying the first invention will be described. A bypass line By that connects the suction side portion In of the compressor 12 and the discharge side is provided. Since the discharge side of the compressor 12 is communicated with the rectifier 9, the bypass line By of this embodiment is provided between the point In and the rectifier 9. The second solenoid valve 5 is provided in the middle of the bypass pipeline By.
1 is inserted and connected. In this embodiment (FIG. 5),
Although it is desirable to provide the dryer 13 shown in the embodiment of the invention of the prior application (FIG. 8), the dryer 13 is omitted in FIG. 5 for simplicity of the drawing. The automatic controller 61 receives the output signal of the pressure sensor 5 of the separator 4 and receives the first signal
A control signal is applied to the solenoid valve 15 and the second solenoid valve 51. The mixed gas accumulates in the separator 4 and the internal pressure rises, and when a predetermined pressure is reached, the first solenoid valve 15 is opened (this operation is similar to that in the invention of the previous application) and at the same time, the second The solenoid valve 51 is closed. When the first solenoid valve 15 is opened, the mixed gas in the separator 4 is sucked into the compressor 12 and fed into the rectifier 9, so that the pressure in the separator 4 rapidly drops, When the pressure sensor 5 outputs a detection signal indicating a pressure drop, the automatic controller 61 closes the first solenoid valve and opens the second solenoid valve 51. During this period, the compressor 12 is continuously operated, but since the second electromagnetic valve 51 is opened at the same time as the closing of the first electromagnetic valve 15, the suction side of the compressor 12 is not closed. I won't. Since the compressor 12 is protected as described above by applying the first invention, it is not necessary to frequently start and stop the compressor 12, and therefore various start-up and stop-ups are caused. There is no risk of failure.

The first aspect of the invention has excellent practical effects as described above, but there is room for improvement in the following points. In the first invention shown in FIG. 5, the first solenoid valve 1
When 5 is closed, the second solenoid valve is open. Therefore, even if the compressor 12 is operated, its suction side I
The pressure of n (suction pressure) does not become too low. If the first solenoid valve 15 is opened in such a state, the mixed gas may flow backward in the direction of arrow r.

FIG. 1 is a system diagram of the second invention, and FIG.
It is an example improved by applying the second invention to the embodiment of the first invention shown in FIG. Next, differences from FIG. 5 will be described, that is, matters improved by applying the second invention. (See FIG. 1) A fixed orifice 52 is inserted and connected in series with the second solenoid valve 51 in the middle of the bypass line By. In the present invention, the fixed orifice is the opposite of the automatic variable orifice. That is, an orifice whose fluid resistance does not change during operation is included in the fixed orifice of the present invention even if it has a structure that can be adjusted manually. (Hereinafter, the fixed orifice may be simply referred to as an orifice). Next, the operation of FIG. 1 will be described in comparison with FIG. 5 (first invention). Since the second solenoid valve 51 is closed while the first solenoid valve 15 is open, the orifice 5
Regardless of the presence or absence of 2, the bypass pipeline By is closed, and the compressor 12 performs its original function (suction and pressure feed of the mixed gas in the separator 4 to supply it to the rectifier 9). In the state in which the first solenoid valve 15 is closed and the second solenoid valve 51 is opened, in FIG. 5 (first invention), the location In on the suction side of the compressor 12 is located inside the rectifier 9. The pressures are almost the same (for example, a relatively high pressure of 0.5 Kgf / cm ² g). On the other hand, in FIG. 1 (second invention),
The circulation flow (arrow s) passing through the bypass pipeline By causes a pressure drop due to the flow resistance of the orifice 52, and the suction side In of the compressor 12 is kept at a lower pressure than in the rectifier 9. Therefore, when the first solenoid valve 15 is opened, the reverse flow of the mixed gas due to the reversal of the pressure distribution is remarkably reduced, and practically no harm is caused. The operating conditions of the bleeding device are not always constant, and therefore the cycle time in which the first solenoid valve 15 and the second solenoid valve 51 are alternately opened and closed also fluctuates. Therefore, it is not easy to maintain the suction side portion In at the optimum pressure. If the pressure of the portion In is too high, there is a risk that the mixed gas may flow backward. Further, if the pressure of the above-mentioned portion In is too low, there is a possibility that trouble may occur in the compressor 12, the compressor driving electric motor and the like. That is, since the extraction is generally performed once or twice a month, the stop time of the extraction device is long. It cannot be ruled out that the pressure in the rectifier 9 has dropped to about atmospheric pressure during this stop period. In addition, during the bleeding operation after the maintenance of the open point inspection,
The pressure inside is atmospheric pressure. Considering the behavior of the extraction device in this state is as follows. Separator 4
The mixed gas accumulates inside and the pressure gradually rises to 0.1
When Kgf / cm ² g is reached and the first solenoid valve 15 is opened, the operation of the compressor 12 is started. However, the first
The opening time of the electromagnetic valve 15 is short, for example, 5 seconds, and therefore the pressure in the rectifier 9 hardly rises. Therefore, the first solenoid valve 15 opens and the second solenoid valve 51 opens.
The pressure of each part when the valve is opened is as follows.

The pressure in the rectifier 9 is about 0 Kgf / cm ² g. The suction pressure of the compressor 12 is, for example, -650 mmHg. The suction pressure of the compressor 12 is too low (generally -600 mm).
(Lower pressure than Kgf / cm ² g) causes a hindrance to the operation of the compressor. Therefore, in order to continue the operation of the compressor 12,
It is necessary to take measures so that the suction side pressure of the compressor 12 becomes an appropriate value.

FIG. 2 shows a second embodiment of the present invention different from the above, and is a system diagram in which a third solenoid valve and an auxiliary orifice are added to the configuration of FIG. The second shown in FIG.
The solenoid valve 51 and the orifice 52 are the components shown in FIG. 1 and are controlled by the automatic controller 61 in the same manner as in the above embodiment (FIG. 1). In this embodiment, the third solenoid valve 53 is provided in parallel with the orifice 52.
Is connected to the auxiliary orifice 54. The automatic controller 61 in this example includes the pressure sensor 9b to the rectifier 9
A signal representing the internal pressure is input, and the third solenoid valve 53 is controlled to open and close according to the internal pressure of the rectifier 9. In this embodiment, the third solenoid valve is opened when the pressure in the rectifier 9 becomes lower than the predetermined pressure P ₁ and closed when it becomes higher than the predetermined pressure P ₂ . The values of P ₁ and P ₂ can be set arbitrarily, but according to the tests and studies by the present inventor, P ₁ > 1.0 Kgf / cm ² g, preferably P ₁ ≈1.4.
Kgf / cm ² g P ₂ <3.0 Kgf / cm ² g Desirably P ₂ ≈1.9
Good results are obtained with Kgf / cm ² g. This is the third solenoid valve 53
The pressure inside the rectifier is 3.0 Kgf / cm while the valve is open.
This is because when the pressure becomes ² g or more, the pressure on the suction side In of the compressor also increases accordingly, and when the first solenoid valve 51 opens, there is a fear of mixed gas backflow. Valve 5
When 3 is closed, the pressure inside the rectifier is 1.0 Kgf
This is because the suction pressure of the compressor 12 is too low when the pressure is less than / cm ² g.

FIG. 3 is a chart showing the operating principle of the embodiment of FIG. 2 according to the second invention and showing the relationship between the opening / closing state of the orifice and the auxiliary orifice and the pressure drop in the bypass pipe. In this graph, the horizontal axis represents the pressure in the rectifier 9 corresponding to the inflow side of the bypass pipeline By. The vertical axis represents the above-mentioned portion In corresponding to the outflow side of the bypass pipeline By, that is, the suction side pressure of the compressor 12. The curve V shows the pressure balance when only the second solenoid valve 51 that opens and closes the flow path of the orifice 52 is open and the third solenoid valve 53 that opens and closes the flow path of the auxiliary orifice 54 is closed. It represents. Also curve W
Shows the pressure balance in a state where both the second and third solenoid valves are opened and the mixed gas can flow through both the orifice 52 and the auxiliary orifice 54. The upper and lower limits shown with parallel diagonal lines in the figure show the upper and lower limits of the control target, respectively. Now, consider a state in which the second solenoid valve 51 is opened to open the flow path of the orifice 52, and the third solenoid valve 53 is also opened to open the flow path of the auxiliary orifice 54. The rectifier 9 on the discharge side of the compressor 12
The balance point between the internal pressure and the pressure on the suction side of the compressor is shown in FIG.
Where is on the curve W of? If the bleeding operation is continued in this state, the rectifier internal pressure gradually rises, and the compressor suction side pressure also rises accordingly. That is, the curve W of FIG.
The upper balance point moves in the direction of arrow a. When the pressure balance changes as described above and reaches the upper limit shown in FIG. 3, the third solenoid valve 53 is closed and the auxiliary orifice 54
Is closed. Looking at this action in FIG. 3,
The balance point reaching the upper right end of the curve W moves on the curve V by moving as shown by an arrow b. When the balance point moved to the upper right on the curve V reaches the upper limit, the pressure is detected by the pressure sensor 9b, and the discharge unit 9c discharges the gas in the rectifier. In this way, the pressure on the suction side In of the compressor 12 is maintained between the upper limit and the lower limit indicated by hatching. As a result, there is no fear that the suction side pressure of the compressor 12 will excessively rise and the mixed gas will flow backward. Figure 3
In the pressure control described above, the flow control of the auxiliary orifice 54 (that is, the opening / closing control of the third solenoid valve 53) is performed on the basis of the pressure (horizontal axis) in the rectifier, but it is easy from the above-described operating principle. As can be understood from the above, it is also possible to perform pressure control with the vertical axis (compressor suction side pressure) in FIG. 3 as a reference. Next, an embodiment based on the suction side pressure of the compressor will be described.

A pressure sensor P shown in phantom in FIG. 2 is provided to detect the pressure on the suction side In of the compressor 12 and input it to the automatic controller 61. The automatic controller 61, the detected pressure opens the auxiliary orifice 54 opens the third solenoid valve 53 becomes the P ₃ below, the auxiliary closing the third solenoid valve 53 when the detected pressure is P ₄ or more orifices The flow path 54 is closed. The above values P ₃ and P ₄ can be set arbitrarily, but according to the tests and studies by the present inventor, good results are obtained when P ₃ > −600 mmHg P ₄ <± 0 mmHg.

This is because if the suction side pressure is ± 0 mmHg or more, a backflow may occur, and if the high vacuum is −600 mmHg or more, the suction pressure of the compressor 12 may be less than the allowable limit.

FIG. 4 shows a bleeder for a refrigerator according to the second invention, and is a system diagram of an embodiment different from the above. When the configuration of this embodiment is compared with the embodiment of FIG. 1, it is equivalent to the fixed orifice 52 replaced by a pressure regulating valve 55. The pressure regulating valve 55 of this example is a pressure reducing valve type pressure regulating valve, and the automatic controller 6
When the first solenoid valve 15 is opened without receiving the direct control of No. 1, the pressure on the downstream side (that is, the suction side In of the compressor 12) of the pressure reducing valve type pressure regulating valve is ± 0 mmHg. 60
Adjust so that the pressure is adjusted to 0 mmHg. Even with this configuration, the same operation and effect as those of the embodiment of FIG. 2 can be obtained.

[0025]

According to the first aspect of the invention, when the first solenoid valve is closed, the second solenoid valve is opened and the bypass line of the compressor is communicated, so that the compressor is continuously operated. Even if it is operated, the suction side does not become a closed shape, and there is no possibility of causing a malfunction in the compressor or activating the safety device. When the first solenoid valve is opened, the second solenoid valve is closed and the bypass line is closed. When the bypass pipeline is closed, it becomes equivalent to a state in which the bypass pipeline is not provided, the compressor performs its original function, and the pressure of the mixed gas in the rectifier is increased to increase the refrigerant gas. The partial pressure is relatively reduced, and the content rate of the accompanying refrigerant gas is reduced.

The second invention is also used in combination with the above-mentioned first invention, and appropriately adjusts the flow resistance of the bypass line in the state where the second solenoid valve is opened, and the discharge side and the suction side of the compressor are suctioned. The pressure difference with the side is automatically maintained at an appropriate value to control the pressure distribution in the vicinity of the separator and the compressor, and in particular, when the first solenoid valve is opened, there is no risk of the mixed gas flowing backward, Also,
When the pressure of the rectifier 9 is low, the excellent practical effect of automatically controlling the suction side pressure of the compressor so as not to fall below the limit is achieved.

[Brief description of drawings]

FIG. 1 is a system diagram of a second invention, which is an example improved by applying the second invention to the embodiment of the first invention shown in FIG.

FIG. 2 is a system diagram showing an embodiment different from the above with respect to the second invention, in which a third solenoid valve and an auxiliary orifice are added to the configuration of FIG.

FIG. 3 is a chart showing the operating principle of the embodiment of FIG. 2 according to the second invention and showing the relationship between the opening / closing state of the orifice and the auxiliary orifice and the pressure drop in the bypass pipeline.

FIG. 4 is a system diagram of an embodiment different from the above, showing a bleeder of a refrigerator according to a second invention.

FIG. 5 is a system diagram of a pressure control mechanism according to a first invention, in which the first invention is applied to the system diagram of FIG. 8 which is an embodiment of the invention of the prior application (Japanese Patent Application No. 4-181035). Improved 1
Here is an example.

FIG. 6 is a system diagram schematically illustrating a refrigerator equipped with a conventional air extraction device.

FIG. 7 is a system diagram showing a conventional example different from FIG. 6 described above.

FIG. 8 is a system diagram showing an embodiment of an extraction device according to the invention of the earlier application.

[Explanation of symbols]

1 ... Refrigerator, 1a ... Condenser, 1b ... Evaporator, 1c ... Compressor, 2 ... Compressor, 4 ... Separator, 6 ... Discharge unit, 7 ...
Float type valve, 8 ... cooling jacket, 9 ... rectifier, 9
a ... Cooling pipe, 9c ... Discharge unit, 10 ... Cold heat source, 10
a ... low temperature fluid, 10b ... compressor, 10c ... cooler, 12
... Compressor, 13, 13 '... Dryer, 14 ... Solenoid valve, 1
5 ... 1st solenoid valve, 51 ... 2nd solenoid valve, 52 ... Fixed orifice, 53 ... 3rd solenoid valve, 54 ... Auxiliary orifice, 55 ... Pressure regulation valve, 61 ... Automatic controller, By ... Bypass pipeline , In ... Suction side of compressor, P ... Pressure sensor, s ... Circulating flow through bypass line, V ... Curve showing pressure balance when fixed orifice is opened and auxiliary orifice is closed, W ... Fixed orifice And a curve showing a pressure balance in a state where the auxiliary orifice is opened, a ... A pressure balance point showing an initial value on the curve V,
b ... Pressure balance point at the lower limit of the pressure control range.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Teruyoshi Miyatake 2-20-36 Takanawa, Minato-ku, Tokyo Hitachi Building Facility Engineering Co., Ltd.

Claims (18)

[Claims] 1. A mixed gas of a non-condensable gas and a refrigerant gas leaking into a refrigerator is extracted and guided to a separator (4) and cooled to liquefy a part of the refrigerant gas. Reflux to the refrigerator, pressurize the residual mixed gas by the compressor (12), and strongly cool in the rectifier (9) to liquefy a part of the refrigerant gas in the residual mixed gas. In the bleeding device for discharging the gas in the rectifier to the atmosphere from the discharge unit (9c) when the gas pressure in the rectifier reaches a predetermined pressure, the separator (4) and the compressor ( 12) and the first
The solenoid valve (15) of
2) A bypass line (B that connects the suction side and the discharge side)
y) is provided, and a second solenoid valve (51) is provided in the bypass line.
And a automatic controller (61) for opening and closing the second solenoid valve (51) when the first solenoid valve (15) is closed. Pressure control mechanism in bleeder. 2. Suction of the compressor (12) by providing a means for suppressing a flow rate in the bypass pipe line in series with the second solenoid valve (51) in the bypass pipe line (By). The side pressure is lowered, and the side pressure is reduced.
A pressure control mechanism in the extraction device of the refrigerator described in. 3. The means for limiting the flow rate in the bypass line (By) is one fixed orifice or a plurality of fixed orifices connected in series. The pressure control mechanism in the extraction device of the refrigerator described in 2. 4. A third solenoid valve (53) separate from the second solenoid valve (51) is provided for the one fixed orifice or a plurality of fixed orifices connected in series. The pressure control mechanism in a bleeder of a refrigerator according to claim 3, further comprising an auxiliary orifice (54) connected in series with the third solenoid valve. 5. The opening and closing of the third solenoid valve (53) is controlled by an automatic controller to which a pressure signal in the rectifier (9) is input, and the suction pressure of the compressor (12) is set to a predetermined value. The pressure control mechanism in a bleeder of a refrigerator according to claim 4, wherein the pressure control mechanism has a structure that is maintained in a pressure range. 6. The third solenoid valve (53) is controlled to be opened and closed by an automatic controller that receives a suction pressure signal of the compressor (12), and the suction pressure of the compressor is maintained within a predetermined pressure range. The pressure control mechanism in the bleeder of the refrigerator according to claim 4, wherein the pressure control mechanism has a dripping structure. 7. The bleed air of the refrigerator according to claim 5 or 6, wherein the predetermined pressure range for maintaining the suction pressure of the compressor (12) is ± 0 mmHg to -600 mmHg. Pressure control mechanism in the device. 8. A second pipe is provided in the bypass pipe (By).
The flow control means provided in series with the solenoid valve (51) of
The pressure control mechanism in the bleeder of the refrigerator according to claim 2, wherein the pressure control mechanism is a pressure regulating valve. 9. The pressure regulating valve is a pressure reducing valve type pressure regulating valve, wherein the pressure on the suction side of the compressor (12) is ± 0 mmHg to −6.
It is characterized by being kept at 00 mmHg,
A pressure control mechanism in the bleeder of the refrigerator according to claim 8. 10. A mixed gas of a non-condensable gas and a refrigerant gas leaking into the refrigerator is extracted and guided to a separator (4) and cooled to liquefy a part of the refrigerant gas. Reflux to the refrigerator, pressurize the residual mixed gas by the compressor (12), and strongly cool in the rectifier (9) to liquefy a part of the refrigerant gas in the residual mixed gas. In the bleeding device for discharging the gas in the rectifier to the atmosphere from the discharge unit (9c) when the gas pressure in the rectifier reaches a predetermined pressure, the separator (4) and the compressor ( 12) and the first
The solenoid valve (15) of
2) A bypass line (B that connects the suction side and the discharge side)
y) is provided, and a second solenoid valve (51) is provided in the bypass line.
The first and second solenoid valves are controlled to be opened and closed in an interlocking manner by an automatic controller (61). When the first solenoid valve is closed, the second solenoid valve is opened to open the A pressure control method in a bleeder of a refrigerator, characterized in that a compressor (12) is protected. 11. A means for suppressing the flow rate in the bypass pipe is provided in series in the bypass pipe (By) in series with the second solenoid valve (51), and the second solenoid valve is Even when the compressor is opened, a differential pressure is generated in the bypass pipe so that the suction of the compressor is higher than the pressure in the separator (4) connected to the suction side of the compressor (12). The pressure control method in a bleeder of a refrigerator according to claim 10, characterized in that the pressure on the side is kept low. 12. In the bypass line (By), 1
The pressure control in the bleeder of the refrigerator according to claim 11, wherein one fixed orifice or a plurality of fixed orifices connected in series is provided to suppress the flow rate in the bypass pipeline. Method. 13. A third solenoid valve (53) separate from the second solenoid valve (51) for the one fixed orifice or a plurality of fixed orifices connected in series.
And an auxiliary orifice (54) connected in series with the third solenoid valve to control the opening and closing of the third solenoid valve separately from the second solenoid valve.
A pressure control method in the bleeder of the refrigerator according to claim 12. 14. The third solenoid valve (53) is controlled to be opened and closed by an automatic controller to which a pressure signal in the rectifier (9) is input, and a suction pressure of the compressor (12) is controlled to a predetermined value. The pressure control method in a bleeder of a refrigerator according to claim 13, characterized in that the pressure control is performed in a pressure range. 15. The third solenoid valve (53) is controlled to be opened and closed by an automatic controller to which a suction pressure signal of the compressor (12) is input, and the suction pressure of the compressor is kept within a predetermined pressure range. The pressure control method in the bleeder of the refrigerator according to claim 13, characterized in that. 16. A predetermined pressure range within which the suction pressure of the compressor (12) should be maintained is ± 0 mmHg to −600 mmH.
The pressure control method in the bleeder of the refrigerator according to claim 14 or 15, wherein g is g. 17. A pressure regulating valve is provided in series with the second solenoid valve (51) in the bypass conduit (By) to automatically control the pressure drop in the bypass conduit. The pressure control method in the extraction device of the refrigerator according to claim 11. 18. A pressure reducing valve is used as the pressure regulating valve, and the suction side pressure of the compressor (12) is ± 0 mmHg to −600 mmH.
The method of controlling pressure in a bleed device for a refrigerator according to claim 17, characterized in that the pressure is controlled to g.