CN211372833U

CN211372833U - Oil return device for air-conditioning compressor suction pipe

Info

Publication number: CN211372833U
Application number: CN201922417168.3U
Authority: CN
Inventors: 孙小红; 满林香
Original assignee: Beihai Vocational College
Current assignee: Beihai Vocational College
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2020-08-28
Anticipated expiration: 2029-12-27

Abstract

The utility model relates to a refrigerating system, in particular to an oil return ware for on air condition compressor suction pipe, include: the device comprises an oil return barrel, a plurality of electromagnetic valves, a plurality of density sensors, a main control module, a first straight pipe, a second straight pipe and a plurality of inclined branch pipes, wherein the first straight pipe and the second straight pipe are arranged in the oil return barrel; the main control module is used for opening the only corresponding electromagnetic valve when the density value of the medium detected by any density sensor is within the preset value range. Compared with the prior art, the oil shortage phenomenon of the compressor is avoided, and the refrigeration oil in the oil return barrel can be recovered in time.

Description

Oil return device for air-conditioning compressor suction pipe

Technical Field

The utility model relates to an oil returning device, in particular to an oil return device for on air condition compressor suction pipe.

Background

In the air-conditioning refrigeration system, the refrigerant oil enters the evaporator along with the exhaust of the compressor and returns to the suction pipe of the compressor along with the return steam. Before entering the compressor, an oil return device is usually provided to ensure that the compressor does not generate wet compression and smoothly returns oil. The solubility of the frozen oil and the refrigerant liquid in the oil return device is reduced at low temperature, the layering condition occurs in an oil return barrel of the oil return device, and the specific gravity of the frozen oil is lighter than that of the refrigerant liquid, so the upper layer of the liquid in the oil return barrel is a rich oil layer rich in the frozen oil, and the lower layer of the liquid in the oil return barrel is a lean oil layer rich in the refrigerant liquid. Because the load change of the frequency conversion multi-split air conditioner compressor is large, the liquid level fluctuation in the oil return barrel frequently causes the instability of the oil return position, a unique oil return port cannot be arranged to enable the refrigeration oil to return to the compressor along with the return air, when the oil level is higher than the unique oil return port, the refrigerant liquid flows in the oil return pipe and the steam suction pipe, or a liquid plug prevents the return air from entering the steam suction pipe, when the oil level is lower than the unique oil discharge port, the refrigerant gas flows in the oil return pipe and the steam suction pipe, the refrigeration oil cannot accurately and timely return to the steam suction pipe port of the compressor to enter the compressor, so that the oil shortage of a compressor lubrication system is caused, the abrasion phenomenon of each transmission part can be caused over time, and the existing method is that a worker adds the lubrication oil to the compressor at regular time to achieve the full lubrication of each moving.

SUMMERY OF THE UTILITY MODEL

An embodiment of the utility model provides an oil return device for on air condition compressor suction pipe, can effectually separate out the refrigeration oil in the oil return device from the cryogen liquid, and inside carrying the better transport of the refrigeration oil that will separate out to the compressor, lubricate the moving part of compressor, thereby not only make the compressor in time retrieve the refrigeration oil in the oil return device, still solved compressor moving part's lack of oil problem simultaneously, avoid adopting artifical mode of refueling.

In order to achieve the above object, an embodiment of the present invention provides an oil return device for use in a suction pipe of an air conditioner compressor, including: an oil return barrel and an oil return pipeline assembly;

the oil return line assembly includes: the oil recovery tank comprises a first straight pipe and a second straight pipe which are arranged in the oil recovery tank, and a plurality of inclined branch pipes arranged between the first straight pipe and the second straight pipe, wherein one end, far away from the bottom of the oil recovery tank, of the first straight pipe is an air inlet end, the air inlet end is exposed above the highest liquid level of the oil recovery tank, one end, far away from the bottom of the oil recovery tank, of the second straight pipe is an air outlet end, the air outlet end is connected with a steam suction pipe of a compressor, one end, opposite to the first straight pipe, of each inclined branch pipe is an air inlet, one end, opposite to the second straight pipe, of each inclined branch pipe is an air outlet, each inclined branch pipe is sequentially arranged along the depth direction of the oil recovery tank, the height, inside the oil recovery tank, of the air inlet of each inclined branch pipe is lower than the height, inside the oil recovery tank, of the air; the air inlet of each inclined branch pipe is connected with the first straight pipe, and the air outlet of each inclined branch pipe is connected with the second straight pipe;

the oil return device further comprises: the density sensors and the electromagnetic valves are the same as the inclined branch pipes in number and are only corresponding to the inclined branch pipes; each electromagnetic valve is respectively arranged at the air outlet of each inclined branch pipe which is only corresponding, and each density sensor is respectively arranged at the oil inlet of each inclined branch pipe which is only corresponding; each electromagnetic valve is used for connecting or disconnecting the second straight pipe with each inclined branch pipe which is only corresponding to the second straight pipe;

when any one of the density sensors detects that the density value of the cooling medium is within a preset value range, the main control module is used for opening the electromagnetic valve uniquely corresponding to the density sensor to enable the inclined branch pipe uniquely corresponding to the electromagnetic valve to be communicated with the second straight pipe;

when any density sensor detects that the density value of the cooling medium is not within the preset value range, the main control module is used for closing the electromagnetic valve uniquely corresponding to the density sensor, so that the inclined branch pipe uniquely corresponding to the electromagnetic valve is disconnected with the second straight pipe.

The utility model discloses embodiment is for prior art, density with the help of the refrigeration oil is less than the characteristic of cryogen liquid density, at practical application's in-process, can carry out real-time detection to the density value of the interior cooling medium of oil return barrel by each density sensor, through the detection to density value in order to distinguish refrigeration oil and cryogen liquid, when the density value of the cooling medium that arbitrary density sensor detected is in predetermineeing the value range, it is rich oil layer that the medium that is in the oil inlet department at this density sensor place is rich for being rich in the refrigeration oil, can open the solenoid valve that corresponds with this density sensor by host system this moment, thereby will switch on with the slope branch pipe that this solenoid valve corresponds uniquely with the second straight tube, so that the oil inlet of this slope branch pipe can possess certain adsorption affinity according to the produced negative pressure of compressor during operation, can be in the medium in the rich oil layer of this liquid level department through this slope branch pipe along with the steam return of evaporimeter, The second straight tube is sucked to the inside of the compressor through the steam suction pipe of the compressor to play a role in lubricating each transmission part in the compressor, so that no matter what liquid level height the oil-rich layer is in the oil return barrel, the oil inlets of different inclined branch pipes can be used for timely recovering the refrigerant oil in the oil return barrel, and the oil shortage of the compressor is avoided. When any density sensor detects that the density value of the cooling medium is not within the preset value range, the density sensor indicates that the medium at the oil inlet where the density sensor is located is a lean oil layer rich in refrigerant liquid, or the density sensor does not detect the cooling medium, at the moment, the electromagnetic valve uniquely corresponding to the density sensor can be closed by the main control module, so that the inclined branch pipe uniquely corresponding to the electromagnetic valve is disconnected from the second straight pipe, an oil inlet of the inclined branch pipe cannot generate adsorption force due to negative pressure generated when the compressor works, the refrigerant liquid in the cooling medium lean oil layer cannot enter the second straight pipe from the inclined branch pipe, and therefore the problem that the refrigerant liquid in the lean oil layer rich in the refrigerant liquid enters the compressor and influences the work of the compressor can be effectively avoided.

In addition, every two adjacent inclined branch pipes are arranged in parallel.

In addition, the inclined branch pipes are arranged at equal intervals.

In addition, on any one inclined branch pipe, the oil inlet is formed in the direction far away from the air outlet.

In addition, the oil inlet is arranged on the side face of the pipe wall of the inclined branch pipe or on one side, opposite to the barrel bottom of the oil return barrel, of the pipe wall of the inclined branch pipe.

And the oil inlets formed in the inclined branch pipes are uniform in bell mouth, and the caliber of one side of the bell mouth facing the inside of the pipe is larger than that of one side of the bell mouth facing the outside of the pipe.

In addition, one side of the oil inlet, which is far away from the inside of the pipe, is also provided with a guide protrusion, and the guide protrusion extends towards the barrel bottom direction of the oil return barrel in an inclined manner.

In addition, the caliber of the air outlet end of the second straight pipe is smaller than that of the other end of the second straight pipe, and the second straight pipe is a conical pipe.

In addition, the oil return ware still includes: and one end of the steam return pipe is inserted into the oil return barrel, and the other end of the steam return pipe is connected with the air return end of the evaporator.

And, the return-steam pipe inserts the one end in the return-steam oil bucket is located on the highest liquid level of return-steam oil bucket, and with the inlet end of first straight tube staggers each other.

Drawings

Fig. 1 is a schematic structural view of a refrigeration system according to a first embodiment of the present invention;

fig. 2 is a schematic view of an oil return device of a refrigeration system according to a first embodiment of the present invention in an operating state;

fig. 3 is a schematic structural diagram of an oil return device according to a first embodiment of the present invention;

fig. 4 is a schematic structural diagram of the oil return device according to the first embodiment of the present invention, in which the second straight pipe is a tapered pipe;

fig. 5 is a schematic structural diagram of another oil return device in the refrigeration system according to the first embodiment of the present invention;

fig. 6 is a system block diagram of an oil return device according to a first embodiment of the present invention;

fig. 7 is a schematic structural view of an oil return line assembly according to a second embodiment of the present invention;

fig. 8 is a schematic view of the connection between the inclined branch pipe and the guide protrusion according to the second embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the following will explain in detail each embodiment of the present invention with reference to the accompanying drawings. However, it will be appreciated by those of ordinary skill in the art that in various embodiments of the invention, numerous technical details are set forth in order to provide a better understanding of the present application. However, the technical solution claimed in the present application can be implemented without these technical details and various changes and modifications based on the following embodiments.

The utility model discloses a first embodiment relates to an oil return ware for on air condition compressor suction pipe, as shown in fig. 1 and fig. 3, include: oil return barrel 1, return oil pipe way subassembly 2. The oil return line assembly 2 includes: set up first straight tube 21 and second straight tube 22 in the oil return barrel 1, set up a plurality of slope branch pipes 23 between first straight tube 21 and second straight tube 22, the one end that the barrel head of oil return barrel 1 was kept away from to first straight tube 21 is inlet end 2, and this inlet end 211 exposes on the highest liquid level of oil return barrel 1, the one end that the barrel head of oil return barrel 1 was kept away from to second straight tube 22 is for giving vent to anger end 221, and should give vent to anger end 221 and compressor 6's steam suction pipe 61 and be connected. Meanwhile, as shown in fig. 3, one end of each inclined branch pipe 23 with respect to the first straight pipe 21 is an air inlet 231, one end of each inclined branch pipe 23 with respect to the second straight pipe 22 is an air outlet 232, the air inlet 231 of each inclined branch pipe 23 is connected with the first straight pipe 21, the air outlet 232 of each inclined branch pipe 23 is connected with the second straight pipe 22, the height of the air inlet 231 of each inclined branch pipe 23 in the oil return barrel 1 is lower than the height of the air outlet 232 in the oil return barrel 1, and the inclined branch pipes 23 are sequentially arranged in the barrel depth direction of the oil return barrel 1. In the present embodiment, as shown in fig. 1 and 3, each inclined branch pipe 23 is further provided with an oil inlet 233.

As shown in fig. 1 and 3, the oil return device of the present embodiment further includes: a plurality of solenoid valves 3, a plurality of density sensor 4 and master control module, and as shown in fig. 6, each solenoid valve 3 and each density sensor 4 all with master control module electric connection. The density sensors 4 and the electromagnetic valves 3 are the same as the inclined branch pipes 23 in number and are only corresponding to each other. Meanwhile, as shown in fig. 1 and 3, each electromagnetic valve 3 is respectively disposed at the air outlet 232 of each inclined branch pipe 23 which is uniquely corresponding, each density sensor 4 is respectively disposed at the oil inlet 233 of each inclined branch pipe 23 which is uniquely corresponding, and each electromagnetic valve 3 is used for connecting or disconnecting the second straight pipe 22 and each inclined branch pipe 23 which is uniquely corresponding.

In the practical application process, as shown in fig. 1 and fig. 2, during the operation of the compressor 6, part of the refrigerant liquid containing the refrigeration oil will enter the evaporator 40 along with the exhaust pipe 62 and sequentially pass through the condenser 20 and the throttle valve 30 to participate in evaporation, and the refrigerant liquid containing the refrigeration oil that is not evaporated by the evaporator 40 will enter the oil return barrel 1 through the air return pipe 50 of the evaporator 40 and be collected by the oil return barrel 1. Due to the low solubility of the refrigerant liquid and the freezing oil contained in the oil return barrel 1 at low temperature, and the low density of the freezing oil compared with the density of the refrigerant liquid, the oil-rich layer 8 rich in the freezing oil floats above the liquid level of the oil-poor layer 7 rich in the refrigerant liquid, and a layering phenomenon occurs, as shown in fig. 2, the upper layer is the oil-rich layer 8 rich in the freezing oil, and the lower layer is the oil-poor layer 7 rich in the refrigerant liquid. Therefore, a certain negative pressure is generated in the suction pipe 61 of the compressor 6 by the pressure of the compressor 6 during operation. Therefore, by means of the negative pressure of the suction pipe 61, as shown in fig. 2, the suction pipe 61 of the compressor 6 can be connected with the gas outlet end 221 of the second vertical pipe 22 of the oil return pipe assembly 2, and by means of the characteristic that the density value of the refrigeration oil is lower than that of the refrigerant liquid, as shown in fig. 2 and fig. 6, the density of the cooling medium in the oil return barrel 1 can be detected in real time by the density sensors 4 disposed at the oil inlets 233 of the different inclined branch pipes 23, and when any one of the density sensors 4 detects that the density value of the cooling medium is within the preset value range, it indicates that the medium at the oil inlet 233 where the density sensor 4 is located is the oil-rich layer 8 rich in the refrigeration oil. At this time, the main control module may open the electromagnetic valve 3 uniquely corresponding to the density sensor 4, so as to conduct the inclined branch pipe 23 corresponding to the electromagnetic valve 3 with the second straight pipe 22, so that the oil inlet 233 of the inclined branch pipe 23 may have a certain adsorption force according to the negative pressure generated when the compressor 6 operates, and thus the medium in the oil-rich layer 8 at the liquid level may be sucked into the compressor 6 through the inclined branch pipe 23 and the second straight pipe 22 and the steam suction pipe 61 of the compressor 6, so as to lubricate each transmission component in the compressor 6. Therefore, no matter what liquid level height of the oil-rich layer 8 in the oil return barrel 1, the refrigeration oil in the oil return barrel 1 can be timely recovered by means of the oil inlets 233 of the different inclined branch pipes 23, and meanwhile, the oil shortage phenomenon of the compressor 6 is avoided.

In contrast, as shown in fig. 2 and 6 in conjunction, when any one of the density sensors 4 detects that the density value of the cooling medium is not within the preset value range, namely, the medium at the oil inlet 21 of the density sensor 4 is indicated to be a lean oil layer 7 rich in refrigerant liquid, or the density sensor 4 does not detect the cooling medium, the electromagnetic valve 3 uniquely corresponding to the density sensor 4 can be closed by the main control module, thereby disconnecting the inclined branch pipe 23 corresponding to the solenoid valve 3 from the second straight pipe 22, so that the oil inlet 233 of the inclined branch pipe 23 does not generate an adsorption force due to a negative pressure generated by the compressor 6 during operation, ensuring that the medium in the lean oil layer 7 does not enter the second straight pipe 22 from the inclined branch pipe 23, thereby effectively avoiding the refrigerant liquid in the lean oil layer 7 from entering the compressor 6 and influencing the operation of the compressor 6.

In the present embodiment, as shown in fig. 1, the return pipe 50 of the evaporator 40 may be inserted into the return drum 1 from the upper opening 11 of the return drum 1, and the entire return pipe 50 may be positioned above the maximum liquid level of the return drum 1 and may be shifted from the air inlet 211 of the first straight pipe 21. Therefore, when the whole refrigeration system is in operation, after the refrigerant oil supplied into the compressor 6 fully lubricates the internal parts thereof, part of the refrigerant oil is discharged into the oil return barrel 1 again along with the steam return pipe 50 of the evaporator 40, so as to be integrated with the original cooling medium in the oil return barrel 1. In addition, since the oil return barrel 1 contains not only the cooling medium but also a part of the cold air gas supplied when the refrigerant liquid is evaporated by the steam return pipe 50 of the evaporator 40, when the refrigeration oil in the oil-rich layer 8 is sucked by the steam suction pipe 61 of the compressor 6 through the negative pressure, the cold air gas filled in the oil return barrel 1 can be sucked into the compressor 6 through the air inlet end 211 of the first straight pipe 21, and the refrigeration effect of the compressor 6 can be further improved.

In addition, it should be noted that, in the present embodiment, as shown in fig. 3, since the height of the air inlet 231 of each inclined branch pipe 23 in the oil return barrel 1 is lower than the height of the air outlet 232 in the oil return barrel 1, when the cooling medium in the oil return barrel 1 passes through any one inclined branch pipe 23, the inclined branch pipe 23 in this state will be forcibly filled with the cooling medium from the oil inlet 233, but since the electromagnetic valve 3 corresponding to the inclined branch pipe 23 is in a closed state, that is, the inclined branch pipe 23 is in a disconnected state with the second straight pipe 22, the cooling medium currently in the inclined branch pipe 23 will not be brought into the compressor 6, and the protection of the compressor 6 can be achieved. When the liquid level in the oil recovery tank 1 drops and the inclined branch pipe 23 is gradually exposed from the liquid level, the cooling medium filled in the inclined branch pipe 23 can be gradually discharged from the oil inlet 233 of the inclined branch pipe 23 along with the drop of the liquid level by means of the inclination of the inclined branch pipe 23, so that the subsequent absorption of the frozen oil in the oil-rich layer 8 by the inclined branch pipe 23 is not influenced. In order to further improve the discharging effect of each inclined branch pipe 23 on the cooling medium, it is preferable that the oil inlet 233 of each inclined branch pipe 23 is opened at an end of each inclined branch pipe 23 far from the air outlet 232, that is, the oil inlet 233 is opened at a position close to the air inlet 231, as shown in fig. 5.

In the present embodiment, as shown in fig. 1 and 3, the first straight pipe 21 and the second straight pipe 22 have the same inner diameter. Of course, in practical applications, the inner diameter of the first straight pipe 21 may be larger or smaller than the inner diameter of the second straight pipe 22. As a preferable scheme, in order to further increase the negative pressure of the second straight pipe 22 when the compressor 6 operates, as shown in fig. 4, the diameter of the air outlet end 221 of the second straight pipe 22 in this embodiment should be smaller than the diameter of the other end, that is, in this embodiment, the second straight pipe 22 is a tapered pipe, so that the negative pressure generated by the second straight pipe 22 can be more intensively applied to each inclined branch pipe 23, and the oil inlet 233 on each inclined branch pipe 23 can more easily suck the medium in the oil-rich layer 8. In addition, in each inclined branch pipe 23 mentioned in the present embodiment, every two adjacent inclined branch pipes 23 are arranged in parallel, and each inclined branch pipe 23 should be arranged at an equal distance as much as possible, so that each inclined branch pipe 23 can be arranged in order in the oil return barrel 1. In the present embodiment, the inclined branch pipes 23 are only disposed parallel to each other, but in the practical application, other arrangement may be adopted, for example, the inclination of each inclined branch pipe 23 may gradually increase or decrease from the bottom 12 of the oil return barrel 1 to the opening 11 of the oil return barrel 1, and in the present embodiment, the arrangement of each inclined branch pipe 23 in the oil return barrel 1 is not specifically limited.

The second embodiment of the present invention relates to an oil return device for a suction pipe of an air conditioner compressor, which is substantially the same as the first embodiment, and is mainly distinguished in that the oil inlet 233 is opened in the process of being opened, as shown in fig. 1 to 3, and in the first embodiment, the oil inlet 233 is opened on the side of the pipe wall of the inclined branch pipe 23. In the present embodiment, as an alternative, the oil inlet 233 may be opened at a side of the inclined branch 233 opposite to the bottom 12 of the oil return barrel 1, as shown in fig. 7. When the oil inlet 233 is arranged on one side of the inclined branch pipe 233 relative to the bottom of the oil return barrel 1, the oil inlet 233 of each inclined branch pipe 23 can be more favorable for discharging the forcibly-poured cooling medium, and meanwhile, the oil inlet 233 of each inclined branch pipe 23 can suck the medium in the oil-rich layer 8 at the first time after the liquid level of the oil-rich layer 8 in the oil return barrel 1 reaches the corresponding height.

It should be noted that in the present embodiment, the oil inlet 233 formed in each inclined branch pipe 23 is a bell mouth, and the diameter of the bell mouth facing the inside of the pipe is larger than the diameter of the bell mouth facing the outside of the pipe. Therefore, when the oil inlet 233 of each inclined branch pipe 23 sucks the medium in the oil-rich layer 8, the suction force can be concentrated, and the oil inlet 233 can suck the medium in the oil-rich layer 8 more easily.

In addition, as a preferable scheme, as shown in fig. 7 and fig. 8, in the present embodiment, a guiding protrusion 234 is further disposed on a side of each oil inlet 233 away from the inside of the barrel, the guiding protrusion 234 is formed by extending and inclining towards the bottom direction of the oil return barrel 1, and when the oil inlet 233 sucks the medium in the oil-rich layer 8, the guiding protrusion 234 can guide the medium, so as to further improve the efficiency of sucking the medium in the oil-rich layer 8 by the oil inlet 233, and make the refrigerant oil in the oil-rich layer 8 enter the inclined branch pipe 23 through the oil inlet 233 more easily. It should be noted that, as shown in fig. 8, the upper surface of the guiding protrusion 234 used in the present embodiment is an inner concave arc surface 235, so that when the oil enters the inclined branch pipe 23 through the guiding protrusion 234 via the oil inlet 233, the oil is prevented from side leakage by the inner concave arc surface 235 of the guiding protrusion 234, thereby increasing the suction amount of the refrigerant oil. Meanwhile, in order to facilitate the density sensor 4 to detect the density value of the medium in the oil-rich layer 8 or the oil-poor layer 7 before the oil-rich layer 8 or the oil-poor layer 7 sinks over the corresponding oil inlet 233, as shown in fig. 7, the density sensor 4 may be disposed on the side of the guide protrusion 234 facing the bottom of the oil return barrel 1, so that the oil-rich layer 8 or the oil-poor layer 7 may be detected by the density sensor 4 in advance before reaching the corresponding oil inlet 233, so that the only corresponding solenoid valve 3 may be opened or closed by the main control module in advance, and while the suction of the frozen oil in the oil-rich layer 8 by the oil inlet 233 of each inclined branch pipe 23 is not affected, the phenomenon that the refrigerant in the oil-poor layer 7 flows into the compressor 6 due to the delayed closing of the solenoid valve can be further avoided.

It will be understood by those skilled in the art that the foregoing embodiments are specific examples of the invention, and that various changes in form and details may be made therein without departing from the spirit and scope of the invention in its practical application.

Claims

1. An oil scavenger for use on a suction pipe of an air conditioning compressor, comprising: an oil return barrel and an oil return pipeline assembly;

the oil return line assembly includes: a first straight pipe and a second straight pipe which are arranged in the oil return barrel, a plurality of inclined branch pipes which are arranged between the first straight pipe and the second straight pipe, one end of the first straight pipe, which is far away from the bottom of the oil return barrel, is an air inlet end, the air inlet end is exposed above the highest liquid level of the oil return barrel, the end, far away from the barrel bottom of the oil return barrel, of the second straight pipe is an air outlet end, the air outlet end is connected with a steam suction pipe of a compressor, one end, opposite to the first straight pipe, of each inclined branch pipe is an air inlet, one end, connected opposite to the second straight pipe, of each inclined branch pipe is an air outlet, each inclined branch pipe is sequentially arranged along the barrel depth direction of the oil return barrel, the height of the air inlet of each inclined branch pipe in the oil return barrel is lower than that of the air outlet in the oil return barrel, and an oil inlet is formed in each inclined branch pipe; the air inlet of each inclined branch pipe is connected with the first straight pipe, and the air outlet of each inclined branch pipe is connected with the second straight pipe;

2. The oil scavenger for use in a suction pipe of an air conditioner compressor as recited in claim 1, wherein each two adjacent ones of said inclined branch pipes are disposed in parallel with each other.

3. The oil scavenger for use in a suction line of an air conditioning compressor as claimed in claim 1, wherein the angled legs are positioned equidistant from one another.

4. The oil scavenger for use in a suction pipe of an air conditioning compressor as claimed in claim 1, wherein the oil inlet is formed in any one of the inclined branch pipes in a direction away from the air outlet.

5. The oil return device for the suction pipe of the air conditioning compressor as claimed in claim 1, wherein the oil inlet is provided on the side surface of the pipe wall of the inclined branch pipe or on the side of the pipe wall of the inclined branch pipe opposite to the bottom of the oil return barrel.

6. The oil scavenger for use in a suction pipe of an air conditioning compressor according to claim 1, wherein the oil inlet provided in each of the inclined branch pipes is a bell-mouth, and the diameter of the bell-mouth on the side facing the inside of the pipe is greater than the diameter of the bell-mouth on the side facing the outside of the pipe.

7. The oil scavenger for use in a suction pipe of an air conditioner compressor as claimed in claim 6, wherein a guiding protrusion is further formed on a side of the oil inlet away from the pipe, and the guiding protrusion extends obliquely toward a bottom of the oil recovery drum.

8. The oil scavenger for use in a suction pipe of an air conditioning compressor as claimed in claim 1, wherein the diameter of the outlet end of the second straight pipe is smaller than the diameter of the other end, and the second straight pipe is a tapered pipe.

9. The oil scavenger for use on a suction line of an air conditioning compressor as recited in claim 1, further comprising: and one end of the steam return pipe is inserted into the oil return barrel, and the other end of the steam return pipe is connected with the air return end of the evaporator.

10. The oil scavenger for use in a suction pipe of an air conditioning compressor as claimed in claim 9, wherein the end of the oil return pipe inserted into the oil return barrel is located above the highest liquid level of the oil return barrel and is offset from the inlet end of the first straight pipe.