JP4694365B2 - Pressure reducer module with oil separator - Google Patents

Description

  The present invention relates to a decompressor module with an oil separator that can be used in a vapor compression refrigeration cycle, particularly in a supercritical refrigeration cycle such as a natural refrigerant.

  The vapor compression refrigeration cycle cools the compressed refrigerant with a radiator, depressurizes the compressed refrigerant with a depressurizer, and evaporates the low-pressure refrigerant with an evaporator to obtain refrigeration capacity. Is common (for example, Patent Document 1).

  In the above-described vapor compression refrigeration cycle, compared with the conventional refrigeration cycle using a chlorofluorocarbon refrigerant, in the refrigeration cycle using a natural system refrigerant such as carbon dioxide, the high-pressure side pressure is set to be higher than the critical pressure of the refrigerant. There is a problem that the efficiency of the refrigeration cycle is low because the required power of the compressor becomes large. As a measure for increasing the efficiency of the refrigeration cycle, among the lubricating oil for lubricating the refrigerant circulating in the refrigeration cycle and the compressor, one that reduces the lubricating oil that hinders heat transfer in the evaporator can be considered. Desirably, when the lubricating oil circulates in the compressor and does not circulate in the refrigeration cycle, the heat transfer of the evaporator can be promoted, resulting in higher refrigeration cycle efficiency. Therefore, how to reduce the lubricating oil flowing into the evaporator is a problem.

The conventional refrigeration cycle is configured as shown in FIG. 6, for example. The refrigeration cycle 101 includes a compressor 102, a radiator 103 that cools the refrigerant that flows out of the compressor 102, and a high temperature that flows out of the radiator 103. An internal heat exchanger 105 that performs heat exchange between the refrigerant and the low-temperature refrigerant flowing out of the accumulator 104 (also serving as a gas-liquid separator) and supplies the low-temperature refrigerant heat-exchanged with the high-temperature refrigerant to the compressor 102; A decompressor 106 for decompressing the refrigerant flowing out from the internal heat exchanger 105, an evaporator 107 for evaporating the refrigerant flowing out from the decompressor 106, and a two-phase refrigerant of a liquid phase gas and a gas phase refrigerant flowing out from the evaporator 107 The accumulator 104 is provided that stores the gas-phase refrigerant and supplies the gas-phase refrigerant to the internal heat exchanger 105.
JP 11-193967 A

  The problem of the present invention is to reduce the lubricating oil flowing into the evaporator so as to increase the refrigeration cycle efficiency, in other words, to increase the heat transfer efficiency of the evaporator, in view of the conventional technology as described above. An object of the present invention is to provide a pressure reducer module with an oil separator that can bypass only the lubricating oil of refrigerant and lubricating oil circulating in the refrigeration cycle before the evaporator.

  In addition, the oil separator, pressure reducer, and filter can be modularized to reduce the number of fastening parts when configuring the refrigeration cycle, and the pressure reduction with the oil separator can be expected to reduce weight and price. Another object is to provide a container module.

In order to solve the above problems, a decompressor module with an oil separator according to the present invention is applied to a vapor compression refrigeration cycle in which a decompressed refrigerant is evaporated to absorb heat and the evaporated refrigerant is sucked and compressed by a compressor. An oil separator that separates the lubricating oil and refrigerant of the compressor is integrated with a decompressor that decompresses the cooled high-pressure refrigerant after being compressed by the compressor, and a passage for the high-pressure refrigerant to be decompressed. A passage for the low-pressure side refrigerant after flowing out from the passage for the high-pressure side refrigerant and passing through the evaporator , and having the oil separator and the decompressor in the passage for the high-pressure side refrigerant and separated by the oil separator A lubricating oil passage for guiding the lubricating oil to a low-pressure refrigerant passage provided below the high-pressure refrigerant passage .

In this oil pressure reducer module with a separator, the passage of the low-pressure side refrigerant that is formed in front of the compressor.

  Furthermore, the low-pressure side refrigerant passage extends in the horizontal direction so that the lubricating oil guided from the oil separator to the low-pressure side refrigerant passage by the lubricating oil passage flows to the outlet side of the low-pressure side refrigerant passage. It is preferable to incline so that the side is down. That is, the separated lubricating oil is caused to flow toward the outlet side of the low-pressure side refrigerant passage using gravity so that the lubricating oil does not flow backward.

  Furthermore, it is also preferable to provide a filter for preventing foreign substances from passing between the inlet and the outlet of the high-pressure side refrigerant passage.

  Moreover, it is preferable that the said pressure reduction device has a mechanism in which a pressure reduction degree is determined based on the information regarding a refrigerating cycle state.

  Further, in the decompressor module with an oil separator according to the present invention, the high pressure side refrigerant inlet portion for forming the high pressure side refrigerant passage, the high pressure side refrigerant outlet portion, and the low pressure for forming the low pressure side refrigerant passage. It is also a preferred embodiment that the side refrigerant inlet portion and the low pressure side refrigerant outlet portion are formed in one block structure. In particular, it is preferable that the decompressor module with an oil separator has a structure that can be directly attached to and detached from the evaporator, for example, as a single component.

  Such a pressure reducer module with an oil separator according to the present invention is particularly suitable for use in a refrigeration cycle that uses carbon dioxide, which is a natural refrigerant.

  The decompressor module with an oil separator according to the present invention is particularly suitable when the vapor compression refrigeration cycle includes a refrigeration cycle of a vehicle air conditioner.

  According to the decompressor module with an oil separator according to the present invention, by using the decompressor module integrated with the oil separator, it is possible to easily bypass the lubricating oil circulating in the refrigeration cycle before the evaporator. Become. Thereby, the improvement of the heat exchange efficiency of the refrigerant | coolant and air in an evaporator and reduction of a refrigerant | coolant pressure loss can be achieved, and the improvement of a refrigerating capacity can be aimed at. As a result, the refrigerant discharge amount of the compressor can be reduced, the power of the compressor can be saved, and the efficiency improvement of the refrigeration cycle can be expected.

  In addition, by modularizing the oil separator, the pressure reducer, and the filter, it is possible to reduce the number of fastening parts when configuring the refrigeration cycle, and to expect weight reduction and price reduction.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a vapor compression refrigeration cycle provided with a decompressor module with an oil separator according to an embodiment of the present invention. The refrigeration cycle 1 shown in FIG. 1 includes a compressor 2, a radiator 3 that radiates high-temperature and high-pressure refrigerant compressed by the compressor 2, a decompressor module 4 with an oil separator, and a decompressor module 4 with an oil separator. The evaporator 5 that evaporates the low-pressure refrigerant decompressed by the decompressor, the gas-liquid separator 6 of the refrigerant, and the internal heat that exchanges heat between the refrigerant from the radiator 3 and the refrigerant from the gas-liquid separator 6. And an exchanger 7.

  The inflow and outflow paths to the decompressor module 4 with an oil separator in the flow of the refrigerant including the lubricating oil circulating in the refrigeration cycle 1 will be described based on the examples shown in FIGS. In this example, the refrigerant inflow and outflow paths to the decompressor module 4 with an oil separator are such that the refrigerant containing lubricating oil that has flowed out of the internal heat exchanger 7 flows from the high-pressure side refrigerant inlet 8 in FIG. It flows out to the high-pressure side refrigerant outlet 9 and flows out to the evaporator 5. Next, the refrigerant flowing out of the evaporator 5 flows in from the low pressure side refrigerant inlet 10 and flows out from the low pressure side refrigerant outlet 11 together with the lubricating oil separated on the high pressure side. The high-pressure side refrigerant passage 19 and the low-pressure side refrigerant passage 20 are formed in the block-shaped module main body 18 so that the entire decompressor module 4 with an oil separator can be handled, installed and detached as a single component. ing.

  For example, as shown in the Mollier diagram of FIG. 4, a refrigeration cycle in which the high-pressure side inlet refrigerant is operated in a liquid phase will be described. The refrigerant and lubricating oil paths in the pressure reducer module 4 with an oil separator are first passed through a filter 15 that holds foreign matter circulated in the refrigeration cycle 1, and then flows into the oil separator 12 to enter the oil separator 12. The refrigerant and the lubricating oil flow so as to be swirled and swirled. At this time, since the density of the lubricating oil is higher than that of the refrigerant, the refrigerant and the lubricating oil swirling in the oil separator 12 in FIG. 2 are concentrated on the side wall side in the oil separator 12 by centrifugal separation. Furthermore, it stagnates near the bottom due to gravity. On the other hand, the liquid refrigerant flows out of the oil separator outlet through the pipe in the oil separator 12, is decompressed by the decompressor 13 to become a two-phase state, and flows out from the high-pressure side refrigerant outlet 9 of the decompressor module 4 with the oil separator. . The decompressor 13 is configured as a variable decompressor in the present embodiment, and the degree of decompression can be adjusted by the decompression movable portion 16 and the spring 17. That is, in the example shown in FIG. 2, the lubricating oil is separated at point A in the Mollier diagram of FIG. 4 or in the vicinity thereof.

  The lubricating oil stagnating near the bottom surface in the oil separator 12 is carried out from the high-pressure side refrigerant passage 19 to the low-pressure side refrigerant passage 20 through the lubricating oil passage 14 by high-low pressure differential pressure, and together with the low-pressure side refrigerant, the low-pressure side refrigerant outlet. 11 flows out. Therefore, the separated lubricating oil is substantially sent to the gas-liquid separator 6 and the compressor 2 by bypassing the evaporator 5 as shown in FIG. The lubricating oil passage 14 prevents the high-pressure side refrigerant from easily flowing out into the low-pressure side refrigerant passage 20 and allows only lubricating oil to easily flow out from the high-pressure side refrigerant passage 19 into the low-pressure side refrigerant passage 20. The pore shape. Further, the low pressure side refrigerant passage 20 is directed from the inlet 10 to the outlet 11 in the horizontal direction so that the lubricating oil flowing out from the lubricating oil passage 14 does not flow out (reverse flow) from the low pressure side refrigerant inlet 10 to the evaporator 5. It is inclined.

  FIG. 5 shows another embodiment, and shows an example in which a decompressor is arranged in front of the oil separator. The reference numerals of the respective parts are the same as those used in FIG. The flow of the refrigerant and the lubricating oil will be described. The refrigerant and the lubricating oil flow in from the high-pressure side refrigerant inlet 8 of the decompressor module 4 with the oil separator, and after being decompressed by the decompressor 13, flow into the oil separator 12. Refrigerant and lubricating oil are separated. The separated refrigerant flows through the pipe in the oil separator 12 and flows out from the oil separator outlet to the high-pressure side refrigerant outlet 9, while the lubricating oil stagnates near the bottom surface in the oil separator 12 and passes through the high-pressure side refrigerant passage 19. It flows down to the low-pressure side refrigerant passage 20 through the lubricating oil passage 14 and flows out from the low-pressure side refrigerant outlet 11 together with the low-pressure side refrigerant. That is, in the example shown in FIG. 5, the lubricating oil is separated at or near point B in the Mollier diagram of FIG.

  The decompressor 13 preferably has a mechanism for determining the degree of decompression based on information related to the refrigeration cycle state. The refrigeration cycle state is, for example, the refrigerant pressure difference between the inlet and outlet of the decompressor. The decompressor 13 in FIG. 2 has a mechanism for adjusting the degree of decompression by changing the refrigerant flow path cross-sectional area by moving the decompression movable part 16 by the balance between the inlet refrigerant pressure of the decompressor 13 and the pressing force of the spring 17. Have.

  Here, the decompression degree adjusting mechanism of the decompressor may uniquely determine the decompression degree from the refrigerant pressure, the refrigerant temperature, or the like of the refrigeration cycle. Further, a solenoid valve may be added to the depressurization degree adjusting mechanism, and the depressurization degree may be determined based on information based on refrigerant pressure, refrigerant temperature, evaporator outlet air temperature, etc. provided in the refrigeration cycle.

  Further, the main body portion of the decompressor module 4 with an oil separator includes a high pressure side refrigerant inlet portion for forming a high pressure side refrigerant passage, a high pressure side refrigerant outlet portion, and a low pressure side for forming a low pressure side refrigerant passage. By arranging the refrigerant inlet part and the low-pressure side refrigerant outlet part in one structure, it is possible to easily connect the pipes connected thereto.

  The decompressor module with an oil separator according to the present invention is suitable for a vapor compression refrigeration cycle that compresses and expands a refrigerant, particularly a refrigeration cycle that uses carbon dioxide, which is a natural refrigerant, as a refrigerant. It is suitable for use in the refrigeration cycle.

It is an equipment distribution diagram of a vapor compression refrigeration cycle provided with a decompressor module with an oil separator concerning one embodiment of the present invention. It is a longitudinal cross-sectional view which shows the structural example of the decompressor module with an oil separator used for the refrigerating cycle of FIG. It is a cross-sectional view of the pressure-reducer module with an oil separator which follows the AA line of FIG. FIG. 2 is a Mollier diagram of the refrigeration cycle of FIG. 1. It is a longitudinal cross-sectional view which shows another structural example of the decompressor module with an oil separator used for the refrigerating cycle of FIG. It is an equipment distribution diagram of a conventional vapor compression refrigeration cycle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Refrigeration cycle 2 Compressor 3 Radiator 4 Pressure reducer module with oil separator 5 Evaporator 6 Gas-liquid separator 7 Internal heat exchanger 8 High pressure side refrigerant inlet 9 High pressure side refrigerant outlet 10 Low pressure side refrigerant inlet 11 Low pressure side refrigerant outlet 12 Oil separator 13 Pressure reducing device 14 Lubricating oil passage 15 Filter 16 Pressure reducing movable portion 17 Spring 18 Module body 19 High pressure side refrigerant passage 20 Low pressure side refrigerant passage

Claims (7)

This is applied to a vapor compression refrigeration cycle in which the decompressed refrigerant is evaporated to absorb heat, and the evaporated refrigerant is sucked and compressed by a compressor. After being compressed by the compressor, the cooled high-pressure refrigerant is decompressed. An oil separator for separating the lubricating oil and refrigerant of the compressor is integrated with the decompressor, and the low-pressure refrigerant after flowing out of the high-pressure refrigerant passage and the high-pressure refrigerant passage after passing through the evaporator Of the low pressure side refrigerant provided in the passage of the high pressure side refrigerant, the oil separator and the pressure reducer, and the lubricating oil separated by the oil separator provided below the passage of the high pressure side refrigerant. A decompressor module with an oil separator, comprising a lubricating oil passage leading to the passage . Furthermore, the low-pressure side refrigerant passage is at its outlet in the horizontal direction so that the lubricating oil guided from the oil separator to the low-pressure side refrigerant passage by the lubricating oil passage flows to the outlet side of the low-pressure side refrigerant passage. 2. The decompressor module with an oil separator according to claim 1 , wherein the decompressor module is inclined so that the side faces downward. Furthermore, between the outlet from the inlet of the passage of the high-pressure side refrigerant, foreign matter characterized by comprising a filter for preventing the passing pressure reducer module with oil separator according to claim 1 or 2. The decompressor module with an oil separator according to any one of claims 1 to 3 , wherein the decompressor has a mechanism in which a degree of decompression is determined based on information on a refrigeration cycle state. A high-pressure side refrigerant inlet part for forming a high-pressure side refrigerant passage, a high-pressure side refrigerant outlet part, a low-pressure side refrigerant inlet part for forming a low-pressure side refrigerant path, and a low-pressure side refrigerant outlet part The decompressor module with an oil separator according to any one of claims 1 to 4 , wherein the decompressor module is formed in one block structure. The decompressor module with an oil separator according to any one of claims 1 to 5 , wherein the refrigerant is made of carbon dioxide. The decompressor module with an oil separator according to any one of claims 1 to 6 , wherein the vapor compression refrigeration cycle includes a refrigeration cycle of a vehicle air conditioner.

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