Manifold

Abstract

To provide a manifold capable of reducing the number of components while improving heat transfer and electric power consumption.SOLUTION: The manifold 100 includes a flow passage housing 105 having a refrigerant flow passage 71,72,73 for circulating the refrigerant, and an oil separator 21 for separating oil contained in the refrigerant circulating in the refrigerant flow passage 72 is formed in the flow passage housing 105.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a manifold. [Background technology]

[0002] In recent years, automobiles equipped with motors as a driving source (such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), and fuel cell electric vehicles (FCEVs)) have become widespread. These automobiles are equipped with batteries to drive the motors. These automobiles have many devices that require cooling, such as the motor (including internal combustion engines such as engines), battery, air conditioner, and ECU, and these are cooled by cooling circuits that circulate coolant or refrigerant. However, each of these devices may have a different optimum operating temperature. In such cases, the temperature of the circulating coolant or refrigerant is controlled by exchanging heat through heat exchangers such as chillers and water-cooled condensers to change the temperature of the circulating coolant or refrigerant for each device with a different operating temperature.

[0003] The cooling system disclosed in Patent Document 1 includes a refrigerant circuit through which a refrigerant circulates. The refrigerant circuit includes a compressor, a condenser, an expansion valve, an evaporator, and the like.

[0004] The cooling system disclosed in Patent Document 2 includes a refrigerant circuit equipped with an oil separator that separates oil contained in the refrigerant flowing out from the compressor. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-139251 [Patent Document 2] Japanese Patent Application Publication No. 2018-015742 Summary of the Invention [Problem to be solved by the invention]

[0006] The refrigerant flowing out of the compressor contains oil, but the refrigerant circuit described in Patent Document 1 does not have an oil separator, so when oil flows into the condenser, an oil film forms on the heat exchange wall, which can hinder heat transfer.

[0007] Although the refrigerant circuit described in Patent Document 2 is provided with an oil separator, arranging the oil separator on the refrigerant circuit increases the area required for the cooling system and the number of parts, leaving room for improvement in terms of the area required for the cooling system, etc.

[0008] The present invention has been made in view of the above-mentioned problems, and its object is to provide a manifold that can reduce the number of parts while improving the heat transfer coefficient and improving power consumption. [Means for solving the problem]

[0009] A characteristic configuration of the manifold according to the present invention is that it includes a flow path housing having a refrigerant flow path through which a refrigerant flows, and an oil separator formed within the flow path housing that separates oil contained in the refrigerant flowing through the refrigerant flow path.

[0010] According to this configuration, since the oil separator is formed inside the flow path housing, the number of parts in the heat exchange system can be reduced compared to when the oil separator is installed independently. Furthermore, by integrating the oil separator into the flow path housing, the circuit can be prevented from becoming complicated. In this way, a manifold that can improve power efficiency with a simple configuration has been provided. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a circuit configuration diagram of a cooling system having a manifold according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram of a manifold. [Figure 3] 3 is a cross-sectional view taken along line III-III in FIG. 2, illustrating an oil separator disposed in a manifold. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of a manifold according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0013] [Cooling system configuration] As shown in Fig. 1, a cooling system A including a manifold 100 according to this embodiment is roughly divided into a coolant circuit B and a refrigerant circuit C. A coolant with high electrical insulation properties, such as an antifreeze containing ethylene glycol as a main component, a long-life coolant (LLC), or a fluorine-based inert liquid, flows through the coolant circuit B, while a refrigerant such as a hydrofluorocarbon (HFC) or a hydrofluoroolefin (HFO) flows through the refrigerant circuit C. In Fig. 1, the portion surrounded by a dashed line is the manifold 100 according to this embodiment.

[0014] The manifold 100 has auxiliary equipment including a flow path housing 105, an oil separator 21, a chiller 110 (an example of an evaporator), a water-cooled condenser 120 (an example of a condenser), a first electric pump 4, a rotary valve 5 consisting of a four-way valve, a second electric pump 7, a switching valve 10 consisting of a three-way valve, a third electric pump 11, a first expansion valve 23, and a second expansion valve 26. In FIG. 1, the auxiliary equipment is depicted as being inside the flow path housing 105, but as shown in FIG. 2, except for the oil separator 21, the auxiliary equipment is actually mounted on the outer surface of the flow path housing 105 and integrated therewith. The oil separator 21 is included in the flow path housing 105 and is formed inside the flow path housing 105. The detailed configuration of the oil separator 21 will be described later.

[0015] FIG. 2 shows a schematic configuration diagram of the manifold 100. However, in FIG. 2, auxiliary equipment (e.g., pumps and valves) other than the oil separator 21, chiller 110, and water-cooled condenser 120 are omitted. In this embodiment, the flow path housing 105 is formed by die-casting using a metal material with high thermal conductivity, including aluminum. Although parting surfaces are not shown in FIG. 2, the flow path housing 105 is formed by joining multiple housing parts. The flow paths and oil separator 21 that constitute the coolant circuit B and the refrigerant circuit C are formed simultaneously when the respective housing parts are molded.

[0016] [Cooling fluid circuit] First, the coolant circuit B will be described. The coolant circuit B is a flow path to the right of the chiller 110 and the water-cooled condenser 120 in FIG. 1. The coolant circuit B has a first external flow path 31 outside the flow path housing 105. The first external flow path 31 is connected to a first internal flow path 41 and a second internal flow path 42 formed inside the flow path housing 105. A radiator 1 is disposed midway along the first external flow path 31. The coolant flows through the second internal flow path 42, the first external flow path 31, the radiator 1, the first external flow path 31, and the first internal flow path 41 in this order. Hereinafter, the upstream side and downstream side of the flow direction of the coolant in the coolant circuit B will also be simply referred to as the upstream side and the downstream side.

[0017] A second external flow path 32 and a third external flow path 33 branch off from the first external flow path 31 downstream of the radiator 1 and upstream of the first internal flow path 41. The second external flow path 32 is connected to a third internal flow path 43 formed inside the flow path housing 105 on its downstream side. The third internal flow path 43 is connected to the second internal flow path 42 on its downstream side. The coolant branched off from the first external flow path 31 to the second external flow path 32 flows through the second external flow path 32, cools the charger 2 and the DC-DC converter 3, and then flows into the third internal flow path 43. The coolant is pressurized in the third internal flow path 43 by the first electric pump 4, and then flows into the second internal flow path 42.

[0018] A fourth internal flow path 44 branches off from the third internal flow path 43 on the upstream side of the first electric pump 4 in the third internal flow path 43. In the state shown in FIG. 1 , the fourth internal flow path 44 is connected to a fifth internal flow path 45 via a rotary valve 5. The downstream side of the fifth internal flow path 45 is connected to the second internal flow path 42.

[0019] The third external flow path 33 is connected downstream to a sixth internal flow path 46 formed inside the flow path housing 105. The sixth internal flow path 46 is connected to a seventh internal flow path 47 via a rotary valve 5. A second electric pump 7 is disposed in the middle of the seventh internal flow path 47. The coolant branched from the first external flow path 31 to the third external flow path 33 flows through the third external flow path 33, cools the power conversion module 6, and flows into the sixth internal flow path 46. In the state shown in FIG. 1 , the coolant is pressurized by the second electric pump 7 in the seventh internal flow path 47 via the rotary valve 5, and then flows out of the flow path housing 105. The power conversion module 6 is a module that integrates a rotating electric machine, a reducer, a differential gear mechanism, and a power converter (inverter) housed in a housing. By rotating the rotary valve 5, the fourth internal flow path 44 and the sixth internal flow path 46 can be connected, and the fifth internal flow path 45 and the seventh internal flow path 47 can be connected.

[0020] The seventh internal flow path 47 is connected to the fourth external flow path 34 outside the flow path housing 105. The fourth external flow path 34 is connected downstream to an eighth internal flow path 48 formed inside the flow path housing 105. The coolant flowing out of the seventh internal flow path 47 flows through the fourth external flow path 34, is cooled by the first heater core 8, is then heated by cooling the battery 9, and flows into the eighth internal flow path 48. The eighth internal flow path 48 is connected downstream to the chiller 110. The downstream side of the chiller 110 is connected to the second internal flow path 42. The coolant flowing through the eighth internal flow path 48 flows into the chiller 110, where it is cooled by the atomized refrigerant that flows in from a third internal refrigerant path 73 (an example of a refrigerant flow path) described later. The coolant flowing through the second internal flow path 42 flows into the first external flow path 31 connected to the outside of the flow path housing 105.

[0021] The first internal flow path 41, which is connected to the first external flow path 31, is connected to the water-cooled condenser 120 on the downstream side. In addition, the switching valve 10 and the third electric pump 11 are arranged in this order in the middle of the first internal flow path 41. The downstream side of the water-cooled condenser 120 is connected to the ninth internal flow path 49. The coolant that has flowed into the first internal flow path 41 is pressurized by the third electric pump 11 and flows into the water-cooled condenser 120. Inside the water-cooled condenser 120, it absorbs heat from the refrigerant in a high-temperature compressed gas state that has flowed in from a second internal refrigerant path 72 (an example of a refrigerant path) described later and is heated. Thereafter, the coolant flows through the ninth internal flow path 49 and flows out of the flow path housing 105.

[0022] The ninth internal flow passage 49 is connected to the fifth external flow passage 35 outside the flow passage housing 105. The fifth external flow passage 35 is connected to a tenth internal flow passage 50 formed inside the flow passage housing 105 on the downstream side. The tenth internal flow passage 50 is connected to the sixth internal flow passage 46 on the downstream side. The coolant flowing out from the ninth internal flow passage 49 flows through the fifth external flow passage 35, is cooled by the second heater core 12, and flows into the tenth internal flow passage 50. The coolant flowing through the tenth internal flow passage 50 flows into the sixth internal flow passage 46.

[0023] The switching valve 10 disposed in the first internal flow path 41 switches the flow direction of the coolant between the first internal flow path 41 and an eleventh internal flow path 51 formed inside the flow path housing 105. The eleventh internal flow path 51 is connected to the tenth internal flow path 50 on the downstream side. When the switching valve 10 is switched so that the coolant flows through the eleventh internal flow path 51, the coolant flows from the first internal flow path 41 through the eleventh internal flow path 51, into the tenth internal flow path 50, and then flows into the sixth internal flow path 46.

[0024] [Refrigerant circuit] Next, the refrigerant circuit C will be described. The refrigerant circuit C is a flow path on the left side of the chiller 110 and the water-cooled condenser 120 in FIG. 1. The refrigerant circuit C is formed mainly inside the flow path housing 105, and a refrigerant flows through it. The refrigerant circuit C has a first internal refrigerant path 71 (an example of a refrigerant flow path) downstream of the chiller 110 in the flow direction of the refrigerant (hereinafter, the upstream side and downstream side of the flow direction of the refrigerant in the refrigerant circuit C will also be simply referred to as the upstream side and downstream side). The refrigerant that flows out of the chiller 110 flows through the first internal refrigerant path 71 and flows out of the flow path housing 105.

[0025] The first internal refrigerant passage 71 is connected to a first external refrigerant passage 61 outside the flow path housing 105. A compressor 22 is disposed in the first external refrigerant passage 61. The first external refrigerant passage 61 is connected downstream to a second internal refrigerant passage 72 (an example of a refrigerant passage) formed inside the flow path housing 105. An oil separator 21 formed inside the flow path housing 105 is disposed in the second internal refrigerant passage 72, and the second internal refrigerant passage 72 is connected downstream to a water-cooled condenser 120 (see also FIG. 2 ). In other words, the oil separator 21 is disposed upstream of the water-cooled condenser 120. The downstream side of the water-cooled condenser 120 is connected to a third internal refrigerant passage 73 (an example of a refrigerant passage) formed inside the flow path housing 105. The third internal refrigerant passage 73 is connected to the chiller 110 via a first expansion valve 23 disposed in the passage. In other words, in the flow path housing 105, the water-cooled condenser 120 is mounted at a position upstream of the refrigerant flow direction in the third internal refrigerant path 73, and the chiller 110 is mounted at a position downstream of the refrigerant flow direction.

[0026] A fourth internal refrigerant passage 74 (an example of a refrigerant passage) branches off from the third internal refrigerant passage 73 upstream of the first expansion valve 23. A second expansion valve 26 is disposed in the middle of the fourth internal refrigerant passage 74. The fourth internal refrigerant passage 74 is connected to a second external refrigerant passage 62 formed outside the flow path housing 105. An evaporator 24 and a check valve 25 are disposed in this order in the second external refrigerant passage 62. The second external refrigerant passage 62 is connected to a fifth internal refrigerant passage 75 (an example of a refrigerant passage) formed inside the flow path housing 105. The fifth internal refrigerant passage 75 is connected to the first internal refrigerant passage 71 on the downstream side.

[0027] An accumulator that separates the liquid refrigerant contained in the vaporized refrigerant may be disposed between the chiller 110 and the compressor 22. Specifically, the accumulator may be connected to the first internal refrigerant passage 71 and the first external refrigerant passage 61. The accumulator may be formed within the flow path housing 105.

[0028] Next, the flow of refrigerant in the refrigerant circuit C will be described. The refrigerant that has become a high-temperature compressed gas in the compressor 22 flows through the first external refrigerant passage 61 and the second internal refrigerant passage 72 and flows into the oil separator 21. The oil separator 21 separates oil contained in the refrigerant that has flowed out from the compressor 22. The oil is a lubricating oil that lubricates the compressor 22, and is contained in the refrigerant in the form of mist when it flows out from the compressor 22. The refrigerant from which the oil has been separated in the oil separator 21 flows through the second internal refrigerant passage 72 and flows into the water-cooled condenser 120. In the water-cooled condenser 120, the refrigerant is condensed and liquefied as heat is absorbed by the cooling liquid that flows in from the first internal flow path 41. The liquefied refrigerant used for cooling the vehicle interior leaves the water-cooled condenser 120, flows through the third internal refrigerant passage 73 and the fourth internal refrigerant passage 74, is expanded by the second expansion valve 26 to become a low-temperature, low-pressure mist, then flows out of the flow path housing 105, flows through the second external refrigerant passage 62, and is sent to the evaporator 24. The mist refrigerant absorbs heat from air introduced from the outside in the evaporator 24 and evaporates. Conversely, the air is cooled by the refrigerant absorbing heat, and is sent into the vehicle interior as cool air. The evaporated refrigerant flows through the check valve 25 arranged in the second external refrigerant passage 62 and flows into the fifth internal refrigerant passage 75, flows out of the flow path housing 105 through the first internal refrigerant passage 71, flows through the first external refrigerant passage 61, and returns to the compressor 22, where it is compressed again to become a high-temperature compressed gas.

[0029] The refrigerant liquefied in the water-cooled condenser 120 that is not used to cool the vehicle interior leaves the water-cooled condenser 120, flows through the third internal refrigerant passage 73, and is expanded by the first expansion valve 23 to become a low-temperature, low-pressure mist, which is then sent to the chiller 110. The mist refrigerant absorbs heat from the coolant flowing in from the eighth internal passage 48 in the chiller 110 and evaporates. The evaporated gaseous refrigerant is sent from the first internal refrigerant passage 71 to the first external refrigerant passage 61. The second external refrigerant passage 62 has a check valve 25, so the gaseous refrigerant that flows out of the chiller 110 does not flow into the evaporator 24. The refrigerant flows through the first external refrigerant passage 61 and returns to the compressor 22, where it is compressed again to become a high-temperature compressed gas.

[0030] If an accumulator is disposed between the chiller 110 and the compressor 22, the refrigerant is evaporated in the chiller 110 or the evaporator 24, and the vaporized refrigerant is sent to the accumulator. In the accumulator, if the gaseous refrigerant contains liquid refrigerant, the liquid refrigerant is separated. The refrigerant flowing out of the accumulator flows through the first external refrigerant passage 61 and returns to the compressor 22.

[0031] [Oil flow path] Next, the oil flow path will be described. The oil flow path is a flow path through which oil separated from the refrigerant in the oil separator 21 flows. The oil flow path has a first internal oil passage 81 on the downstream side of the oil flow direction relative to the oil separator 21 (hereinafter, the upstream side and downstream side of the oil flow direction in the oil flow path will also be simply referred to as the upstream side and downstream side). The first internal oil passage 81 is formed inside the flow path housing 105, and is connected to the third internal refrigerant passage 73 on the upstream side of the first expansion valve 23 and the second expansion valve 26. In addition, a second internal oil passage 82 formed inside the flow path housing 105 branches off from the first internal oil passage 81. The second internal oil passage 82 is connected to a first external oil passage 91 outside the flow path housing 105, and the first external oil passage 91 is connected to the compressor 22 on the downstream side.

[0032] The oil separated from the refrigerant in the oil separator 21 flows through the first internal oil passage 81 and into the third internal refrigerant passage 73, where it is mixed with the refrigerant flowing through the third internal refrigerant passage 73. Alternatively, the oil flows through the first internal oil passage 81, the second internal oil passage 82, and the first external oil passage 91, and then is returned to the compressor 22. A switching valve that switches the flow passage between the first internal oil passage 81 and the second internal oil passage 82 may be integrally formed with the flow passage housing 105.

[0033] If oil flows into the water-cooled condenser 120, the oil adheres to the heat exchange walls of the water-cooled condenser 120, forming an oil film that inhibits heat transfer between the refrigerant and the coolant. In this embodiment, the oil contained in the refrigerant is separated in the oil separator 21 upstream of the water-cooled condenser 120, thereby suppressing the inflow of oil into the water-cooled condenser 120 and preventing deterioration of heat transfer in the water-cooled condenser 120. Furthermore, by separating the oil upstream of the water-cooled condenser 120, the inflow of oil into the evaporator 24 and the chiller 110 can also be suppressed, thereby suppressing a decrease in the refrigeration effect due to changes in sensible heat of the oil. The oil content in the refrigerant after passing through the oil separator 21 may be, for example, 10% or less, preferably 5% or less, and more preferably 1% or less.

[0034] On the other hand, if no oil flows into the evaporator 24 or the chiller 110, oil foaming is unlikely to occur. Oil foaming is a phenomenon in which refrigerant dissolves in oil and bubbles like boiling, which promotes refrigerant evaporation and improves heat transfer coefficient. Therefore, in this embodiment, the oil separated in the oil separator 21 flows through the first internal oil passage 81 and is returned to the refrigerant flowing through the third internal refrigerant passage 73 upstream of the chiller 110. This allows refrigerant containing a predetermined amount of oil to flow into the evaporator 24 or the chiller 110, thereby achieving the effect of improving heat transfer through oil foaming. The oil content of the refrigerant flowing into the evaporator 24 or the chiller 110 may be, for example, 2% to 6%, and more preferably 3% to 5%. The first internal oil passage 81 may be provided with an adjustment valve or the like for adjusting the amount of oil flowing into the third internal refrigerant passage 73.

[0035] [Configuration of flow path housing] Normally, heat exchange between the coolant and the refrigerant is carried out only in the heat exchangers, the chiller 110 and the water-cooled condenser 120. However, in this embodiment, by bringing the flow paths of the coolant circuit B and the refrigerant circuit C close to each other inside the flow path housing 105, heat exchange is carried out not only in the chiller 110 and the water-cooled condenser 120 but also between the flow paths.

[0036] 2, the flow paths connected to the chiller 110 are arranged such that, in the flow path housing 105, the eighth internal flow path 48 of the coolant circuit B flowing into the chiller 110 and the first internal refrigerant path 71 of the refrigerant circuit C flowing out of the chiller 110 are arranged parallel to and adjacent to each other, and the second internal flow path 42 of the coolant circuit B flowing out of the chiller 110 and the third internal refrigerant path 73 of the refrigerant circuit C flowing into the chiller 110 are arranged parallel to and adjacent to each other. In this case, the flow direction of the coolant flowing through the eighth internal flow path 48 is opposite to the flow direction of the refrigerant flowing through the first internal refrigerant path 71, and the flow direction of the coolant flowing through the second internal flow path 42 is opposite to the flow direction of the refrigerant flowing through the third internal refrigerant path 73. In addition, in the flow path housing 105, the eighth internal flow path 48 and the first internal refrigerant path 71 exchange heat at an L-shaped portion, and the second internal flow path 42 and the third internal refrigerant path 73 exchange heat at a linear portion. By configuring the internal flow paths in this manner in the flow path housing 105, heat exchange occurs not only within the chiller 110, but also between the coolant flowing through the eighth internal flow path 48 and the refrigerant flowing through the first internal refrigerant path 71, and also between the coolant flowing through the second internal flow path 42 and the refrigerant flowing through the third internal refrigerant path 73. Because heat exchange also occurs between the internal flow paths outside the chiller 110 and the internal refrigerant path, sufficient cooling performance can be obtained even if a small chiller 110 is used.

[0037] 2, the flow paths connected to the water-cooled condenser 120 are arranged such that the first internal flow path 41 of the coolant circuit B flowing into the water-cooled condenser 120 and the third internal refrigerant path 73 of the refrigerant circuit C flowing out of the water-cooled condenser 120 are arranged parallel to and adjacent to each other in the flow path housing 105, and the ninth internal flow path 49 of the coolant circuit B flowing out of the water-cooled condenser 120 and the second internal refrigerant path 72 of the refrigerant circuit C flowing into the water-cooled condenser 120 are arranged parallel to and adjacent to each other. In this configuration, the flow direction of the coolant flowing through the first internal flow path 41 is opposite to the flow direction of the refrigerant flowing through the third internal refrigerant path 73, and the flow direction of the coolant flowing through the ninth internal flow path 49 is opposite to the flow direction of the refrigerant flowing through the second internal refrigerant path 72. In the flow path housing 105, the first internal flow path 41 and the third internal refrigerant path 73 exchange heat at a linear portion, and the ninth internal flow path 49 and the second internal refrigerant path 72 exchange heat at a linear portion. By configuring the internal flow paths in this manner in the flow path housing 105, heat exchange occurs not only within the water-cooled condenser 120, but also between the coolant flowing through the first internal flow path 41 and the refrigerant flowing through the third internal refrigerant path 73, and also between the coolant flowing through the ninth internal flow path 49 and the refrigerant flowing through the second internal refrigerant path 72. In this way, heat exchange also occurs between the internal flow paths outside the water-cooled condenser 120 and the internal refrigerant path, so that sufficient cooling performance can be obtained even if a small water-cooled condenser 120 is used.

[0038] [Oil separator] As shown in Fig. 2, an oil separator 21 is formed inside the flow path housing 105 of the manifold 100 according to this embodiment. Specifically, as shown in Fig. 3, a centrifugal oil separator 21 that separates oil by utilizing the difference in mass between the refrigerant and the oil is formed inside the flow path housing 105. The oil separator 21 has a cylindrical portion 21a, an opening 21b, a reduced-diameter portion 21c, and a refrigerant outlet portion 21d. Hereinafter, in the oil separator 21 shown in Figs. 2 and 3, the upward direction along the plane of the paper will be referred to as the upper side of the oil separator 21, and the downward direction will be referred to as the lower side of the oil separator 21. Furthermore, the direction from the top to the bottom of the oil separator 21 will be referred to as the vertical direction.

[0039] The cylindrical portion 21a is formed in a cylindrical shape extending along the vertical direction, and is connected to the second internal refrigerant passage 72 via an opening 21b provided in the upper part of the side wall. That is, the refrigerant flowing through the second internal refrigerant passage 72 flows into the internal space of the cylindrical portion 21a from the opening 21b. The downstream end (opening 21b) of the second internal refrigerant passage 72 is preferably located between the center and the upper part of the flow path housing 105 in the up-down direction (direction parallel to the vertical direction).

[0040] The upper end of the cylindrical portion 21a is sealed, and the lower end of the cylindrical portion 21a is provided with a reduced diameter portion 21c whose inner diameter decreases as it extends downward. The inner peripheral surface of the reduced diameter portion 21c is preferably inclined or curved at a certain angle relative to the downward direction. The inner peripheral surface of the reduced diameter portion 21c functions as a guide surface that guides the oil separated from the refrigerant downward. The reduced diameter portion 21c is connected to the first internal oil passage 81 at its lower end.

[0041] A cylindrical refrigerant outlet portion 21d is disposed coaxially with the cylindrical portion 21a in the internal space of the cylindrical portion 21a. The outer diameter of the refrigerant outlet portion 21d is smaller than the inner diameter of the cylindrical portion 21a. The vertical dimension of the refrigerant outlet portion 21d may be substantially the same as or smaller than the vertical dimension of the cylindrical portion 21a. The upper end of the refrigerant outlet portion 21d is connected to the second internal refrigerant passage 72. The axial center of the refrigerant outlet portion 21d and the axial center of the cylindrical portion 21a do not have to coincide. The refrigerant outlet portion 21d may be configured as a separate body from the flow path housing 105.

[0042] The inner circumferential wall of the oil separator 21 at the cylindrical portion 21a or the reduced diameter portion 21c may have an uneven shape. The uneven shape may be a groove or a textured shape formed on the inner circumferential wall. The groove may be formed along the circumferential direction of the cylindrical portion 21a or the reduced diameter portion 21c, or may be formed in a spiral shape or may be formed along the vertical direction. The uneven shape formed on the inner circumferential wall of the cylindrical portion 21a or the reduced diameter portion 21c facilitates separation of oil contained in the refrigerant.

[0043] Next, the operation of the oil separator 21 will be described. The refrigerant that flows from the second internal refrigerant passage 72 into the cylindrical portion 21a through the opening 21b swirls along the inner circumferential wall of the cylindrical portion 21a, forming a swirling flow centered on the axis of the cylindrical portion 21a. When the swirling flow is formed, the oil contained in the refrigerant is forced outward of the swirling flow while swirling, and adheres to the inner circumferential wall. If the inner circumferential wall has an uneven shape, the oil is more likely to adhere to the inner circumferential wall, and the oil is more likely to be separated from the refrigerant. The refrigerant moves downward in the cylindrical portion 21a and then flows into the second internal refrigerant passage 72 through the refrigerant outlet portion 21d. This separates the oil from the refrigerant.

[0044] The oil separated by the swirling flow in the cylindrical portion 21a moves along the inner circumferential wall of the cylindrical portion 21a to the reduced diameter portion 21c. Oil may be stored in the reduced diameter portion 21c, and the oil separator 21 may function as an oil reservoir. By storing oil in the reduced diameter portion 21c, it is possible to adjust the amount of oil flowing through the first internal oil passage 81, and therefore the amount of oil flowing into the evaporator 24 or the chiller 110. It is also possible to adjust the amount of oil returned to the compressor 22. The inner diameter of the first internal oil passage 81 is preferably smaller than that of the third internal refrigerant passage 73, etc.

[0045] In this way, by forming the oil separator 21 integrally with the flow path housing 105, the oil separation function can be integrated into the manifold 100, making it possible to reduce the number of parts such as piping. It is also possible to prevent the circuit from becoming complicated. Furthermore, if the oil separator is integrated with the compressor 22, the vibration of the compressor 22 is likely to affect the oil separator 21, making it difficult to separate the oil. However, in this embodiment, the oil separator 21 is arranged independently of the compressor 22, so this problem can be solved.

[0046] Other Embodiments (a) In the above embodiment, the oil separator 21 is of a centrifugal separation type, but it may also be of an impingement separation type, a baffle type in which a baffle plate is provided to separate the oil, or a demister type in which metal fibers such as wire mesh are used to separate the oil. In particular, if the oil separator 21 is of the impingement separation type, the structure of the oil separator 21 can be simplified, which makes it easy to form the flow path housing 105. In either case, if the inner peripheral wall of the oil separator 21 has an uneven shape, oil separation can be facilitated.

[0047] (b) In addition to the oil separator 21, the compressor 22 may also be provided with an oil separator. If the compressor 22 is provided with an oil separator, it is possible to further reduce the amount of oil contained in the refrigerant flowing out from the compressor 22. This makes it possible to obtain a necessary and sufficient oil separation function even with a small oil separator 21, and makes it possible to reduce the size of the entire manifold 100.

[0048] (c) In the above embodiment, the first internal oil passage 81 is provided inside the flow path housing 105, but the first internal oil passage 81 may be provided outside the flow path housing 105. Furthermore, the first internal oil passage 81 does not have to be provided, and all of the oil separated in the oil separator 21 may be returned to the compressor 22 via the second internal oil passage 82 and the first external oil passage 91. Alternatively, if the compressor 22 is provided with an oil separator and a sufficient amount of oil is returned from the oil separator to the compressor 22, the second internal oil passage 82 and the first external oil passage 91 do not have to be provided, and it is sufficient to provide only the first internal oil passage 81. This simplifies the configuration of the manifold 100.

[0049] (d) In the above embodiment, the second internal oil passage 82 branches off from the first internal oil passage 81 , but the second internal oil passage 82 may also be connected to the oil separator 21 .

[0050] (e) The oil flowing through the first internal oil passage 81 may be cooled by an optional cooling mechanism. The cooling mechanism may be provided in the manifold 100. By mixing the oil whose temperature has been lowered by the cooling mechanism with the refrigerant in the third internal refrigerant passage 73, it is possible to lower the temperature of the refrigerant flowing into the evaporator 24 or the chiller 110. This makes it possible to suppress a decrease in the refrigeration effect of the chiller 110 or the like due to the sensible heat of the oil, and also makes it easier for oil foaming to occur, thereby improving thermal efficiency. Furthermore, by lowering the temperature of the refrigerant flowing into the chiller 110 or the like, it is possible to increase the refrigeration capacity of the chiller 110 or the like.

[0051] In the above-described embodiment, the following configurations are envisioned. (1) A manifold 100 having a flow path housing 105 having refrigerant flow paths (first internal refrigerant path 71, second internal refrigerant path 72, third internal refrigerant path 73) through which a refrigerant flows, and an oil separator 21 is formed within the flow path housing 105 to separate oil contained in the refrigerant flowing through the refrigerant flow path (second internal refrigerant path 72).

[0052] According to this configuration, the oil separator 21 is formed in the flow path housing 105, which makes it possible to reduce the number of parts compared to when the oil separator 21 is disposed independently. Furthermore, the function of the oil separator 21 is integrated into the flow path housing 105, and the circuitry can be prevented from becoming complicated. As a result, it is possible to provide a manifold 100 that can improve power efficiency with a simple configuration.

[0053] (2) In the manifold 100 of (1), the inner peripheral wall of the oil separator 21 preferably has an uneven shape.

[0054] According to this configuration, the oil separated from the refrigerant easily adheres to the inner peripheral wall, making it easier to separate the oil from the refrigerant, and improving the function of the oil separator 21.

[0055] (3) In the manifold 100 of (1) or (2), it is preferable that the flow path housing 105 further has oil flow paths (first internal oil path 81, second internal oil path 82) for circulating the oil separated in the oil separator 21.

[0056] According to this configuration, by integrally forming the oil flow paths (first internal oil path 81, second internal oil path 82) in the flow path housing 105, the function of circulating oil in the manifold 100 can be integrated and the number of parts can be reduced.

[0057] (4) In any of the manifolds 100 of (1) to (3), it is preferable that a condenser (water-cooled condenser 120) that condenses the refrigerant is integrated into the flow path housing 105, and the oil separator 21 is provided upstream of the condenser (water-cooled condenser 120) in the refrigerant flow path (second internal refrigerant path 72).

[0058] According to this configuration, the oil separator is provided upstream of the condenser (water-cooled condenser 120), which can prevent oil from flowing into the condenser (water-cooled condenser 120). This prevents an oil film from forming in the condenser (water-cooled condenser 120), improving the heat transfer coefficient. [Industrial Applicability]

[0059] The present invention can be used in a manifold that includes a flow path housing having a coolant flow path through which a coolant flows. [Explanation of symbols]

[0060] 21: oil separator, 71: first internal refrigerant passage (refrigerant passage), 72: second internal refrigerant passage (refrigerant passage), 73: third internal refrigerant passage (refrigerant passage), 74: fourth internal refrigerant passage (refrigerant passage), 75: fifth internal refrigerant passage (refrigerant passage), 81: first internal oil passage (oil passage), 82: second internal oil passage (oil passage), 100: manifold, 105: passage housing, 120: water-cooled condenser (condenser)

Claims

1. a flow path housing having a refrigerant flow path through which a refrigerant flows; The manifold has an oil separator formed in the flow path housing, which separates oil contained in the refrigerant flowing through the refrigerant flow path.

2. The manifold according to claim 1 , wherein the inner peripheral wall of the oil separator has an uneven shape.

3. 2. The manifold according to claim 1, wherein the passage housing is further formed with an oil passage for circulating oil separated by the oil separator.

4. a condenser that condenses the refrigerant is integrated into the flow path housing, 4. The manifold according to claim 1, wherein the oil separator is provided in the refrigerant flow path upstream of the condenser.

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