JP6131621B2 - Oil separator - Google Patents

Description

  The present invention relates to an oil separator.

  Conventionally, in a refrigeration apparatus, an oil separator is used together with a compressor or the like in order to separate the lubricating oil flowing so as to accompany the refrigerant from the refrigerant.

  As such an oil separator, for example, as described in Patent Document 1 (Japanese Patent Laid-Open No. 2005-180808), the diameter near the inlet of the outlet pipe for allowing the refrigerant to flow out gradually increases toward the end. An example has been proposed in which the pressure loss is reduced by increasing the pressure loss.

  Here, the oil separator is required to perform efficient separation of the lubricating oil from the refrigerant.

  However, in the oil separator described in the above-mentioned Patent Document 1 (Japanese Patent Laid-Open No. 2005-180808), the flow rate of the refrigerant and the lubricating oil is reduced by enlarging the diameter of “near” the inlet of the outlet pipe. Although the separation efficiency of the lubricating oil can be improved, it cannot be said that the “inlet” of the outlet pipe has been devised to secure a sufficient area.

  This invention is made | formed in view of the point mentioned above, The subject of this invention is providing the oil separator which can improve the isolation | separation efficiency of lubricating oil in the inlet_port | entrance of outlet piping.

An oil separator according to a first aspect is an oil separator for separating lubricating oil flowing together with a refrigerant from the refrigerant, the container, an inlet pipe connected to the container, and one end located inside the container. Thus, an outlet pipe connected to the container is provided. The container is provided between the upper cylindrical portion, the lower cylindrical portion having a larger inner diameter than the upper cylindrical portion and provided below the upper cylindrical portion, and the lower end portion of the upper cylindrical portion and the upper end portion of the lower cylindrical portion. And an intermediate diameter-enlarged portion configured such that the inner diameter increases toward the lower side. At one end of the outlet pipe, an opening having a larger area than the flow path cross-sectional area near one end of the outlet pipe is provided so as to face a direction inclined with respect to the direction in which the flow path near one end of the outlet pipe extends. ing. The inlet pipe is connected to the upper cylindrical portion. The opening is provided at the height position of the intermediate enlarged portion.

  Here, the “channel cross-sectional area” in the vicinity of one end of the outlet pipe refers to an area in a cross section perpendicular to the main flow direction of the refrigerant in the vicinity of one end of the outlet pipe.

  In addition, the shape of the outlet pipe is not particularly limited, and may be, for example, a cylinder or an ellipse.

  Here, the direction of the opening provided at one end of the outlet pipe of the oil separator may be vertically downward or obliquely downward.

  In this oil separator, the opening at one end of the outlet pipe does not face the direction in which the flow path near one end of the outlet pipe extends, but in the direction in which the flow path near one end of the outlet pipe extends. It is provided to face the inclined direction. For this reason, it is possible to increase the area of the opening of the outlet pipe as compared with the case where the opening faces the direction in which the flow path near one end of the outlet pipe extends. Thereby, it is possible to effectively reduce the flow velocity of the lubricating oil in the vicinity of the opening at one end of the outlet pipe, and to make it difficult for the lubricating oil to be accompanied by the refrigerant flow.

  The oil separator which concerns on a 2nd viewpoint is an oil separator which concerns on a 1st viewpoint, Comprising: The opening provided in the end of outlet piping has faced diagonally downward. The edge part at the lower end of the opening of the outlet pipe functions as a collecting part for collecting lubricating oil.

  In this oil separator, since the opening of the outlet pipe faces diagonally downward, the edge of the opening is not located at the same height in the vertical direction, but the edge of the opening is in the vertical direction. The posture is inclined. For this reason, in the vicinity of the opening of the outlet pipe, the lubricating oil trapped at the edge of the opening of the outlet pipe due to the reduced flow velocity is collected at the inclined lower end portion of the edge of the opening of the outlet pipe. . As a result, the size of the oil droplets of the lubricating oil increases at the lower edge of the opening of the outlet pipe, so that it can be dropped downward by its own weight and is not easily accompanied by the flow of the refrigerant flowing into the outlet pipe.

  The oil separator according to the third aspect is the oil separator according to the first aspect or the second aspect, wherein the outlet pipe flows toward the one end side of the outlet pipe in a portion located inside the container. It has a pipe expansion part with an increased road cross-sectional area. The opening provided at one end of the outlet pipe has a larger area than the channel cross-sectional area of the expanded pipe portion, and is provided to face a direction inclined with respect to the direction in which the expanded pipe portion extends.

  In this oil separator, since the outlet pipe is provided with the expanded portion, it is possible to further reduce the flow rates of the refrigerant and the lubricating oil that are about to flow into the outlet pipe. And the opening of outlet piping is provided so that it may incline in the edge part of the pipe expansion part. For this reason, the area of the opening of the outlet pipe is widely secured by both the area increasing effect by expanding the pipe and the area increasing effect by inclining.

  Thereby, the separation efficiency of the lubricating oil from the refrigerant can be further increased, and the lubricating oil can be more effectively suppressed from flowing out of the oil separator.

  In the oil separator according to the first aspect, it is possible to effectively reduce the flow velocity of the lubricating oil in the vicinity of the opening at one end of the outlet pipe, thereby making it difficult for the lubricating oil to be accompanied by the refrigerant flow.

  In the oil separator which concerns on a 2nd viewpoint, it can be dropped below with dead weight, and becomes difficult to be accompanied by the flow of the refrigerant | coolant which flows in into exit piping.

  In the oil separator according to the third aspect, it is possible to further increase the separation efficiency of the lubricating oil from the refrigerant and more effectively suppress the lubricating oil from flowing out of the oil separator.

It is a schematic block diagram of the air conditioning apparatus which concerns on one Embodiment. It is a schematic external appearance block diagram of an oil separator. It is a top view schematic block diagram of an oil separator. It is a schematic block diagram of the lower end vicinity of internal outlet piping. It is a top view schematic block diagram of the oil separator which concerns on other embodiment (5-1).

  Hereinafter, an air conditioner 1 employing an oil separator according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a refrigerant circuit diagram showing a refrigerant circuit 10 of the air conditioner 1.

(1) Schematic configuration of air conditioner 1 In the air conditioner 1, an outdoor unit 2 as a heat source side device and an indoor unit 4 as a use side device are connected by a refrigerant pipe, and the use side device is arranged. Perform air conditioning of the space. The air conditioner 1 includes a refrigerant circuit 10, various sensors, and a control unit 70.

  The refrigerant circuit 10 includes an accumulator 28, a compressor 21, an oil separator 30, an oil return pipe 29, a four-way switching valve 24, an outdoor heat exchanger 25, an outdoor expansion valve 27, a first refrigerant communication pipe 6, and an indoor heat exchanger. 51 and the second refrigerant communication pipe 7 and the like are connected.

  The outdoor unit 2 includes an accumulator 28, a compressor 21, an oil separator 30, an oil return pipe 29, a four-way switching valve 24, an outdoor heat exchanger 25, an outdoor expansion valve 27, an outdoor fan 26, and an outdoor control unit 72. Etc. are housed.

  The indoor unit 4 houses an indoor heat exchanger 51, an indoor fan 52, an indoor temperature sensor 53, an indoor control unit 74, and the like.

  The outdoor unit 2 and the indoor unit 4 are connected via a first refrigerant communication pipe 6 and a second refrigerant communication pipe 7.

  The four-way switching valve 24 can switch between a cooling operation cycle and a heating operation cycle. In FIG. 1, the connection state when performing the cooling operation is indicated by a solid line, and the connection state when performing the heating operation is indicated by a dotted line. During the cooling operation, the outdoor heat exchanger 25 functions as a refrigerant cooler, and the indoor heat exchanger 51 functions as a refrigerant heater. During the heating operation, the indoor heat exchanger 51 functions as a refrigerant cooler, and the outdoor heat exchanger 25 functions as a refrigerant heater.

  The indoor temperature sensor 53 in the indoor unit 4 is disposed on the indoor air intake side, and the temperature before the indoor unit 4 takes in the room and passes through the indoor heat exchanger 51 (that is, the room temperature) is measured. To detect.

  The control unit 70 includes an outdoor control unit 72 that is disposed in the outdoor unit 2 and controls the devices of the outdoor unit 2, an indoor control unit 74 that is disposed in the indoor unit 4 and controls the devices of the indoor unit 4, and a user The controller 71 that accepts various setting inputs from each other and performs various display outputs and various sensors are connected by a communication line 70a. The control unit 70 performs various controls for the air conditioner 1.

  In addition, although the combination of the refrigerant | coolant and refrigerator oil used in the air conditioning apparatus 1 is not specifically limited, For example, when a refrigerant | coolant is R410A, you may use ether type synthetic oil (for example, FVC68D) as refrigerator oil, When the refrigerant is R134a, an ether-based synthetic oil (for example, FVC46D) may be used as the refrigerating machine oil, and when the refrigerant is R404A, an ether-based synthetic oil (for example, FVC50K) may be used as the refrigerating machine oil. However, a combination of these may be used together as a mixed refrigerant and a compatible refrigerating machine oil. In each of the above combinations, when the refrigeration oil and the refrigerant are separated in the container body 31 of the oil separator 30, the refrigeration oil is located below the refrigerant (the specific gravity of the refrigeration oil is greater than that of the refrigerant). It is preferable.

(2) Configuration and Form of Oil Separator FIG. 2 is a schematic external configuration diagram of the oil separator 30. In FIG. 3, the top view schematic structure figure of the oil separator 30 is shown. In FIG. 4, the schematic block diagram of the lower end vicinity of the internal outlet piping 23a is shown. In FIG. 2, the internal shape and thickness of the container body 31 are indicated by dotted lines.

  The oil separator 30 is for separating the lubricating oil from the fluid discharged from the compressor 21 in which the lubricating oil and the refrigerant are mixed. The oil separator 30 mainly includes the container main body 31 and the compressor 21. It has the inlet piping 22 extended from the container main body 31 toward the discharge side, and the outlet piping 23 extended from the container main body 31 toward the four-way switching valve 24 side.

  The container main body 31 includes an upper cover 31a, an upper cylindrical portion 31b, an intermediate enlarged diameter portion 31c, a lower cylindrical portion 31d, and a lower cover 31e in order from the vertical upper side to the lower side. The container main body 31 is a pressure container, and the material and the thickness are configured so as to satisfy a predetermined standard. The upper cylindrical portion 31b is a cylindrical member and is connected to an inlet pipe 22 described later. The lower cylindrical portion 31d is a cylindrical member whose vertical direction is the axial direction, and has a larger inner diameter than the upper cylindrical portion 31b. The vertical length of the lower cylindrical portion 31d is configured to be longer than the vertical length of the upper cylindrical portion 31b. The lower end portion of the upper cylindrical portion 31b and the upper end portion of the lower cylindrical portion 31d are gently connected via an intermediate enlarged diameter portion 31c. The intermediate diameter enlarged portion 31c is configured such that the inner diameter increases as it goes downward in the vertical direction. An upper end portion of the upper cylindrical portion 31b is covered with an upper cover 31a. The upper cover 31a is provided with an opening penetrating in the vertical direction at the upper end portion in order to pass an outlet pipe 23 described later. A lower end portion of the lower cylindrical portion 31d is covered with a lower cover 31e. The lower cover 31e is provided with an opening penetrating in the vertical direction at the lower end portion in order to allow the oil return pipe 29 to pass therethrough.

  The oil return pipe 29 is welded and fixed to the lower cover 31e via a cylindrical fixing member 29p provided inside the opening of the lower cover 31e and outside the oil return pipe 29 in the radial direction. An oil return pipe 29 extending from the lower cover 31 e of the oil separator 30 is provided with an accumulator 28 and a compressor so as to return the lubricating oil separated in the container body 31 and collected downward to the downstream side of the compressor 21. 21.

  The inlet pipe 22 has one end connected to the discharge side pipe of the compressor 21 and the other end connected to the upper cylindrical portion 31b. The inlet pipe 22 and the upper cylindrical portion 31b are configured such that the inlet pipe 22 extending in the horizontal direction is connected to the upper portion of the upper cylindrical portion 31b. The connection position between the inlet pipe 22 and the upper cylindrical portion 31 b is located above the opening at the lower end of the internal outlet pipe 23 a of the outlet pipe 23. Here, as shown in the top sectional view of FIG. 3, the inlet pipe 22 and the upper cylindrical portion 31 b are provided inside the opening provided on the side surface of the upper cylindrical portion 31 b and outside the inlet pipe 22 in the radial direction. It is fixed by welding via the cylindrical fixing member 22p. Here, as shown in FIG. 3, the inner inlet pipe 22a, which is the inner part of the container main body 31, in the inlet pipe 22 is connected to a position shifted from the axis of the upper cylindrical portion 31b, and the inner inlet pipe 22a. Is positioned so as to be gently connected in the tangential direction of the inner periphery of the upper cylindrical portion 31b. That is, the radially outer portion of the upper cylindrical portion 31b in the inner periphery near the tip of the internal inlet pipe 22a is connected so as to be gently along the inner peripheral surface of the upper cylindrical portion 31b. The internal inlet pipe 22a is a cylindrical pipe. Also, the external inlet pipe 22b connected to the discharge side of the compressor 21 in the inlet pipe 22 and located outside the container body 31 is also a cylindrical pipe, and the inner diameter thereof is the same as that of the internal inlet pipe 22a. It is the same. Further, an end of the external inlet pipe 22b opposite to the curved part 22c side is provided with a pipe expanding part 22q for connecting to a pipe extending from the discharge side of the compressor 21. The internal inlet pipe 22a and the external inlet pipe 22b are provided so that the height positions in the vertical direction are approximately the same, and are connected via a curved portion 22c that is curved at about 90 degrees on a horizontal plane. For this reason, the refrigerant discharged from the discharge side of the compressor 21 is greatly bent in the flow direction immediately before flowing into the container body 31.

  One end of the outlet pipe 23 is connected to the pipe on the four-way switching valve 24 side, and the other end is connected to the upper cover 31a of the container body 31 in the vertical direction. The outlet pipe 23 and the upper cover 31a are located inside an opening provided so as to penetrate the upper cover 31a in the vertical direction and through a cylindrical fixing member 23p provided on the radially outer side of the outlet pipe 23. It is fixed by welding.

  The outlet pipe 23 includes an internal outlet pipe 23a extending vertically downward from the upper cover 31a of the container body 31 toward the inside of the container body 31, and a pipe expanding portion 23b provided at the lower end of the internal outlet pipe 23a. ing. The internal outlet pipe 23a is a straight pipe that extends straight in the vertical direction. The inner diameter of the internal outlet pipe 23a is not particularly limited, and may be, for example, 10% or more and 50% or less of the inner diameter of the upper cylindrical portion 31b of the container body 31. The expanded pipe portion 23b has an upper end connected to the lower end of the internal outlet pipe 23a, and is provided so that the axial direction is a vertical direction so as to be within the vertical width of the intermediate enlarged diameter portion 31c of the container body 31. ing. The inner diameter of the expanded pipe portion 23b is configured to be larger than the inner diameter of the internal outlet pipe 23a. Although it does not specifically limit, the internal diameter of the pipe expansion part 23b can be 1.2 times or more and 2.0 times or less of the internal diameter of the internal outlet piping 23a. Thus, since the inner diameter of the expanded pipe portion 23b is larger than the inner diameter of the internal outlet pipe 23a, the sectional area of the expanded pipe section 23b in the horizontal plane is configured to be larger than the sectional area of the inner outlet pipe 23a in the horizontal plane. ing. As shown in FIG. 4, the expanded pipe portion 23b has an opening 23c formed so that the lower end is cut off obliquely. The opening 23c is opened so as to communicate the inside of the pipe expanding portion 23b downward, and the normal line of the opening surface faces obliquely downward. An opening edge 23x at the lower end of the expanded portion 23b and at the lower end of the opening 23c has a predetermined thickness. In addition, although the inclination angle with respect to the horizontal surface of the opening surface of the opening 23c is not specifically limited, For example, it can be 30 degree | times or more and 70 degrees or less.

(3) Separation Action of Lubricant from Refrigerant in Oil Separator 30 The high-pressure and high-temperature gas refrigerant discharged from the discharge side of the compressor 21 is accompanied by a large amount of lubricating oil.

  The fluid in which the refrigerant and the lubricating oil are mixed flows from the compressor 21 to the front of the inlet pipe 22. When this fluid bends the curved portion 22c of the inlet pipe 22, the gas refrigerant and the lubricating oil having different specific gravity and viscosity are separated from each other. Specifically, when bending at the curved portion 22c of the inlet pipe 22, centrifugal force is applied, and the gas refrigerant and the lubricating oil having a higher specific gravity are directed outward (outside the inner periphery of the curved portion 22c). Pressed.

  Thus, the lubricating oil that has flowed up to the outlet of the internal inlet pipe 22a in the inlet pipe 22 in a state separated from the gas refrigerant, flows on the inner peripheral surface of the upper cylindrical portion 31b of the container body 31 along the flow velocity. And is collected under the container body 31 by its own weight along the inner peripheral surface of the container body 31.

  Here, since the opening 23c of the pipe expanding portion 23b constituting the lower end of the outlet pipe 23 is located near the axis of the intermediate enlarged diameter portion 31c away from the wall surface of the container main body 31, the container main body 31. The lubricating oil descending along the inner peripheral surface of the inner pipe is unlikely to be accompanied by the gas refrigerant toward the opening 23c of the expanded portion 23b of the outlet pipe 23.

  In addition, since the outlet pipe 23 is configured such that the inner diameter of the expanded pipe portion 23b at the lower end is larger than the inner diameter of the inner outlet pipe 23a, the gas refrigerant that tends to rise inside the expanded section 23b of the outlet pipe 23. Will pass through a wider part than the inside of the internal outlet pipe 23a. For this reason, it is possible to suppress an increase in the flow velocity.

  Further, the outlet pipe 23 is configured such that the opening 23c provided in the expanded pipe portion 23b at the lower end is configured so that the normal line of the opening surface does not face vertically downward, but obliquely below, so that the opening surface method The opening area can be secured wider than in the case where the line is configured to face vertically downward. Therefore, the gas refrigerant that is going to rise through the inside of the opening 23c of the expanded pipe portion 23b tries to pass through a wider part than the inside of the expanded pipe portion 23b (the area of the surface perpendicular to the axial direction of the expanded pipe portion 23b). Will do. For this reason, it is possible to suppress the increase in the flow velocity more effectively and smallly.

  As described above, since the flow rate of the gas refrigerant to be sucked through the opening 23c of the outlet pipe 23 is suppressed to be small, it is suppressed that the lubricating oil is accompanied by the gas refrigerant and flows in the outlet pipe 23. Has been. Therefore, it can suppress that lubricating oil flows out from the container main body 31 to the four-way selector valve 24 side.

  Then, as described above, the lubricating oil collected below the container body 31 is returned again to the compressor 21 via the oil return pipe 29.

(4) Features of the present embodiment In the oil separator 30 of the present embodiment, the opening 23c of the outlet pipe 23 is located away from the wall surface of the container body 31 and in the vicinity of the axial center of the intermediate enlarged portion 31c. The lubricating oil descending while turning along the inner peripheral surface in the container main body 31 is difficult to be sucked into the opening 23 c of the outlet pipe 23.

  In addition, the opening 23c of the outlet pipe 23 is provided so as to incline the expanded portion 23b having an inner diameter larger than that of the internal outlet pipe 23a, so that a sufficiently large opening area can be secured. For this reason, the flow rate of the gas refrigerant which is going to pass through the opening 23c of the outlet pipe 23 can be kept small.

  Furthermore, since the opening 23c of the outlet pipe 23 is provided at a height position of the intermediate enlarged diameter portion 31c of the container body 31, the momentum of the gas refrigerant flowing in and descending from the upper cylindrical portion 31b of the container body 31 is also obtained. It is weakened.

  Therefore, it is possible to suppress the flow rate of the gas refrigerant that is going to rise through the opening 23c of the outlet pipe 23 to be sufficiently small and to prevent the lubricating oil from being accompanied.

  Moreover, since the opening 23c of the outlet pipe 23 is provided so as to be inclined, the opening edge portion 23x constituting the vicinity of the lower end of the outlet pipe 23 allows the lubricating oil separated from the gas refrigerant to be on the outer surface of the outlet pipe 23. Even if it adheres to the inner surface, it is lowered so as to cover the surface of the expanded portion 23b of the outlet pipe 23 and collected in one place while applying the surface tension of the oil droplets at the opening edge 23x at the lower end. Can do. For this reason, the size of the oil droplet can be gradually grown at the opening edge portion 23x, and the oil droplet is dropped to the lower end of the container body 31 by its own weight without being sucked into the outlet pipe 23 along the flow of the gas refrigerant. It is possible.

  As a result, the separated lubricating oil is mixed with the gas refrigerant again and is prevented from flowing out of the oil separator 30 via the outlet pipe 23, and the lubricating oil is supplied to the inner peripheral surface of the container body 31. It is possible to collect it downward by lowering it while turning it.

  As described above, the lubricating oil collected below the container body 31 is again returned via the oil return pipe 29 while suppressing the lubricant oil from flowing out from the container body 31 through the outlet pipe 23. It is possible to return to the compressor 21.

(5) Other embodiments (5-1)
In the said embodiment, the case where the opening 23c of the lower end of the internal outlet piping 23a was provided in the pipe expansion part 23b was mentioned as an example, and was demonstrated.

  On the other hand, for example, as shown in FIG. 5, the expanded pipe portion 23 b in the above embodiment is not provided, and the opening 223 c is provided so as to be inclined at the lower end of the internal outlet pipe 223 a. You may employ | adopt the outlet pipe 223 made. Moreover, the opening edge part 223x similar to the opening edge part 23x of the said embodiment is located in the lower end of the exit piping 223. FIG.

  In this case, if the inclination angle of the opening 223c is the same as that of the above-described embodiment, the opening area of the opening 223c is reduced by the amount where the tube expansion portion 23b in the above-described embodiment is not provided. However, as shown in FIG. 5, the opening area of the opening 223c may be sufficiently large by providing a larger inclination angle than the opening 23c of the above embodiment.

  Even in the example of this other embodiment (5-1), by ensuring a sufficiently large opening area of the opening 223c, the flow rate of the passing gas refrigerant can be kept small, and the lubricating oil can be separated into the oil separator. It is possible to make it difficult to flow out from 30 to the outside.

DESCRIPTION OF SYMBOLS 1 Air conditioning apparatus 22 Inlet piping 22c Bending part 23 Outlet piping 23a Internal outlet piping 23b Expanding part 23c Opening 23x Opening edge (collection part)
28 Accumulator 29 Oil return pipe 30 Oil separator 31 Container body (container)
31a Upper cover 31b Upper cylindrical part 31c Middle diameter-expanded part 31d Lower cylindrical part 31e Lower cover 223 Outlet pipe 223a Inner outlet pipe 223c Opening 223x Opening edge (collecting part)

Japanese Patent Laid-Open No. 2005-180808

Claims (3)

An oil separator (30) for separating the lubricating oil flowing with the refrigerant from the refrigerant,
A container (32);
An inlet pipe (22) connected to the vessel;
Outlet pipes (23, 223) connected to the container such that one end is located inside the container;
With
The container (32) includes an upper cylindrical portion (31b), a lower cylindrical portion (31d) having a larger inner diameter than the upper cylindrical portion (31b) and provided below the upper cylindrical portion (31b), An intermediate enlarged portion (31c) provided between the lower end portion of the upper cylindrical portion (31b) and the upper end portion of the lower cylindrical portion (31d) and configured to increase in inner diameter as it goes downward; Have
At one end of the outlet pipe (23, 223), an opening (23c, 223c) having a larger area than the flow path cross-sectional area near the one end of the outlet pipe extends, and a flow path near the one end of the outlet pipe extends. It is provided to face the direction inclined with respect to the direction ,
The inlet pipe (22) is connected to the upper cylindrical part (31b),
The opening (23c, 223c) is provided at a height position of the intermediate enlarged diameter portion (31c) ,
Oil separator (30). An opening (23c, 223c) provided at one end of the outlet pipe (23, 223) faces obliquely downward,
The edge part of the lower end of the opening of the outlet pipe functions as a collecting part (23x, 223x) for collecting lubricating oil.
The oil separator according to claim 1. The outlet pipe (23) has a pipe expansion part (23b) in which the cross-sectional area of the flow path increases toward the one end side of the outlet pipe in the portion located inside the container,
The opening (23c) provided at one end of the outlet pipe has a larger area than the flow passage cross-sectional area of the expanded pipe portion (23b) and faces an inclined direction with respect to the direction in which the expanded pipe portion extends. Provided,
The oil separator according to any one of claims 1 and 2.

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