Oil return barrel type evaporator

Abstract

The utility model provides an oil returning barrel type evaporator which comprises an outer layer barrel wall, an inner layer barrel wall, a first end wall, a second end wall, a refrigerant inlet pipe, a refrigerant outlet pipe and a second annular partition plate, the second annular partition plate is arranged on the inner layer barrel wall in a sleeved mode, and the outer layer barrel wall surrounds the outer side of the inner layer barrel wall and the outer side of the second annular partition plate. The first end wall is connected with one end of the outer-layer barrel wall and one end of the inner-layer barrel wall in a sealed mode, the second end wall is connected with the other end of the outer-layer barrel wall and the other end of the inner-layer barrel wall in a sealed mode, an evaporation cavity is formed between the outer-layer barrel wall and the inner-layer barrel wall, an oil return cavity is formed between the second annular partition plate and the second end wall, and the evaporation cavity and the oil return cavity are annular cavities. The oil return cavity is located at one end of the evaporation cavity, a second flow guide hole used for enabling the oil return cavity to be communicated with the evaporation cavity is formed in the second annular partition plate, the oil return cavity is communicated with at least one refrigerant outlet pipe, and the other end of the evaporation cavity is communicated with at least one refrigerant inlet pipe. According to the evaporator, a metal spiral pipe is omitted, and lubricating oil can still flow back smoothly.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of refrigeration equipment, more exactly relates to a kind of oil return bucket type evaporator. BACKGROUND

[0002] Some refrigeration equipment such as ice blender are provided with refrigeration circuit composed of evaporator, compressor and condenser, in the prior art, the evaporator includes barrel shell and evaporating pipe welded in the barrel shell, the evaporating pipe is composed of metal spiral pipe, the side of evaporating pipe opposite to the inner wall of barrel shell is abutted on the inner wall of barrel shell to realize heat conduction, and the two pipe heads of evaporating pipe are extended out of barrel shell to supply refrigerant to flow in and out. The evaporating pipe originally only has the outside in contact with the inner wall of barrel shell for heat conduction, and the area of external heat exchange is small, and since the flatness of the outer wall of metal spiral pipe is poor, the evaporating pipe and the inner wall of barrel shell are in point contact, the contact area is small, and the area of external heat exchange is even smaller, so the cooling efficiency is low.

[0003] During the operation of compressor, lubricating oil for cooling lubricating bearing and other components inevitably enters compression cavity to mix with refrigerant, and enters evaporating pipe with refrigerant, in order to avoid the contact of refrigerant and lubricating oil with cooled object, metal pipe is completely sealed to the outside. The existing technology always uses metal spiral pipe to manufacture evaporator, which can also ensure that lubricating oil can smoothly return to compressor with refrigerant, because if the volume of lubricating oil diffused with refrigerant in evaporator is too large, the pressure difference provided by compressor can not make lubricating oil return smoothly, and over time, lubricating oil will be deposited in evaporator, which causes the lack of oil in compressor, and the parts in compressor can be overheated and damaged due to the lack of timely lubrication and cooling. SUMMARY

[0004] The technical problem to be solved by the utility model is to provide a kind of oil return bucket type evaporator, which is beneficial to the return of lubricating oil to compressor.

[0005] The technical solution of the utility model is to provide a kind of oil return bucket type evaporator, which includes outer barrel wall, inner barrel wall, first end wall, second end wall, refrigerant inlet pipe, refrigerant outlet pipe and second annular partition, the second annular partition is sleeved on the inner barrel wall, the outer barrel wall is wrapped on the outer side of the inner barrel wall and the second annular partition, the first end wall is sealingly connected with one end of the outer barrel wall and the inner barrel wall, the second end wall is sealingly connected with the other end of the outer barrel wall and the inner barrel wall, the evaporating cavity is formed between the outer barrel wall and the inner barrel wall, the oil return cavity is formed between the second annular partition and the second end wall, the evaporating cavity and the oil return cavity are both annular cavities, the oil return cavity is located at one end of the evaporating cavity, the second annular partition is provided with second flow guide hole for connecting the oil return cavity with the evaporating cavity, the oil return cavity is connected with at least one refrigerant outlet pipe, and the other end of the evaporating cavity is connected with at least one refrigerant inlet pipe.

[0006] Compared with the prior art, the oil-returnable bucket type evaporator has the following advantages: although the metal spiral pipe is cancelled, the lubricating oil entering the evaporator from the compressor along with the refrigerant can still smoothly return to the compressor, because the lubricating oil entering the evaporating cavity from the refrigerant inlet pipe can enter the oil-returning cavity through the flow guide hole, the distance between the second annular partition plate and the second end wall can be reduced to make the volume of the oil-returning cavity smaller, and under the pressure difference, the lubricating oil accumulated in the oil-returning cavity can smoothly return to the compressor along with the refrigerant through the refrigerant outlet pipe, which is beneficial to avoiding the oil shortage of the compressor, thereby avoiding the overheating damage of the parts in the compressor due to the lack of timely lubrication and cooling.

[0007] Preferably, one end of the refrigerant outlet pipe is a third pipe opening, the third pipe opening is arranged on the second annular partition plate and communicates with the oil-returning cavity, the refrigerant outlet pipe extends towards the direction of the first end wall, and the other end of the refrigerant outlet pipe is a fourth pipe opening, the fourth pipe opening is located on the side of the first end wall outside the evaporating cavity. With this structure, it is convenient to adapt to the product in which the inlet and outlet pipe openings of the refrigerant are located at one end of the whole machine, and the structure is simple and convenient for assembling the refrigerant outlet pipe.

[0008] Preferably, a first annular partition plate is further arranged on the inner bucket wall, the outer bucket wall surrounds the outside of the first annular partition plate, a distribution cavity is formed between the first annular partition plate and the first end wall, the distribution cavity is an annular cavity, and a first flow guide hole for communicating the distribution cavity with the evaporating cavity is arranged on the first annular partition plate; one end of the refrigerant inlet pipe is a first pipe opening, the first pipe opening is arranged on the first end wall and communicates with the distribution cavity, and the other end of the refrigerant inlet pipe is a second pipe opening, the second pipe opening is located on the side of the first end wall outside the evaporating cavity. With this structure, the distribution cavity is beneficial to the uniform diffusion of the refrigerant to the evaporating cavity.

[0009] Preferably, the refrigerant outlet pipe comprises an outlet pipe main pipe and a plurality of outlet pipe branch pipes, one end of the outlet pipe branch pipe is a third pipe opening, the other end is a fourth pipe opening, all the third pipe openings are uniformly distributed on the second annular partition plate and communicate with the oil-returning cavity, and all the fourth pipe openings communicate with the outlet pipe main pipe. With this structure, the refrigerant and the lubricating oil in the oil-returning cavity can be uniformly returned, and the accumulation of the lubricating oil on one side to cause poor oil return is avoided.

[0010] Preferably, a plurality of second limiting protrusions are arranged between the second annular partition plate and the second end wall, and the second annular partition plate and the second end wall are respectively limited on the two sides of the second limiting protrusions, so that the oil-returning cavity is formed between the second annular partition plate and the second end wall. With this structure, the distance between the second annular partition plate and the second end wall can be conveniently controlled during assembly, so that the volume of the oil-returning cavity is smaller.

[0011] Preferably, the second limiting bump is in one-piece structure with the second annular partition plate, the second limiting bump is a structure bent from the second annular partition plate, and the second flow guide hole is a plurality of small holes or notches left on the second annular partition plate after the second limiting bump is bent. With this structure, the second limiting bump and the second flow guide hole can be obtained simultaneously through one stamping or bending process, thereby reducing the processing cost of the second annular partition plate.

[0012] Preferably, the second limiting bump is provided with a second flow guide arc surface, and the second flow guide arc surface is connected with the second annular partition plate. With this structure, the second flow guide arc surface plays a role in guiding the lubricating oil, which is conducive to the flow of the lubricating oil from the evaporation cavity into the oil return cavity along the second flow guide arc surface.

[0013] Preferably, the first flow guide hole is a plurality of small holes uniformly distributed on the end face of the first annular partition plate, or a plurality of notches uniformly distributed on the inner ring edge of the first annular partition plate. With this structure, the refrigerant can be evenly diffused from the distribution cavity into the evaporation cavity, thereby improving the cooling efficiency.

[0014] Preferably, the first flow guide hole is formed by the gap between the first annular partition plate and the inner layer barrel wall and / or the gap between the first annular partition plate and the outer layer barrel wall. With this structure, the refrigerant can be diffused along the inner layer barrel wall or the outer layer barrel wall and evenly diffused from the distribution cavity into the evaporation cavity, which is conducive to the full output of cold energy by the inner layer barrel wall or the outer layer barrel wall, and facilitates assembly. The first annular partition plate and the inner layer barrel wall or the outer layer barrel wall only need to be gap-fitted and spot-welded.

[0015] Preferably, the device includes an outer tube, an inner tube, and a first end plate, a second end plate, a first annular partition, and a second annular partition, all of which are annular structures. The first and second annular partitions are welded to the inner sides of both ends of the inner tube. The outer tube and the inner tube are coaxially sleeved. The outer and inner annular edges of the first end plate are sealed and welded to one end of the outer tube and the inner tube, respectively. The outer and inner annular edges of the second end plate are sealed and welded to the other end of the outer tube and the inner tube, respectively. An annular cavity evaporation chamber is formed between the outer tube and the inner tube. An annular cavity distribution chamber is formed between the first end plate and the first annular partition at one end of the evaporation chamber. An annular cavity oil return chamber is formed between the second end plate and the second annular partition at the other end of the evaporation chamber. Both the distribution chamber and the oil return chamber are connected to the evaporation chamber. The wall of the outer tube constitutes the outer barrel wall, the wall of the inner tube constitutes the inner barrel wall, the first end plate constitutes the first end wall, the second end plate constitutes the second end wall, the refrigerant inlet pipe is connected to the distribution chamber, and the refrigerant outlet pipe is connected to the oil return chamber. With this structure, the manufacturing process of the recirculating oil drum evaporator of this utility model is further simplified. It only requires welding the first annular baffle and the second annular baffle to the inner sides of both ends of the inner tube, then connecting the outer tube and the inner tube coaxially, and finally sealing and welding the first end plate and the second end plate to both ends of the outer tube and the inner tube. The production process is less complex, more efficient, and less costly. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the recirculating oil drum evaporator of this utility model.

[0017] Figure 2 for Figure 1 A sectional view.

[0018] Figure 3 This is a schematic diagram of the internal structure of the recirculating oil drum evaporator of this utility model.

[0019] Figure 4 This is another internal structural diagram of the recirculating oil drum evaporator of this utility model.

[0020] Figure 5 This is a schematic diagram of the structure of the second annular baffle in the recirculating oil drum evaporator of this utility model.

[0021] Figure 6 This is a magnified view of a portion of the structure of the second annular partition in this utility model.

[0022] As shown in the figure: 1. Outer barrel wall, 2. Inner barrel wall, 3. First end wall, 4. Second end wall, 5. Evaporation chamber, 6. Refrigerant inlet pipe, 6-1. First inlet, 6-2. Second inlet, 7. Refrigerant outlet pipe, 7-1. Third inlet, 7-2. Fourth inlet, 8. First annular baffle, 8-1. First refrigerant outlet through hole, 8-2. First guide hole, 8-3. First limiting protrusion, 9. Distribution chamber, 10. Oil return chamber, 11. Outlet main pipe, 12. Second annular baffle, 12-2. Second guide hole, 12-3. Second limiting protrusion, 12-4. Second guide arc surface. Detailed Implementation

[0023] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of exemplary embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements.

[0024] In the accompanying drawings, the thickness, size, and shape of the objects have been slightly exaggerated for illustrative purposes. The drawings are for illustrative purposes only and are not drawn to scale.

[0025] It should also be understood that the terms "comprising," "having," "including," and "containing," when used in this specification, indicate the presence of the stated features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or combinations thereof. Furthermore, when expressions such as "...at least one" appear after a list of listed features, they modify the entire listed feature, not individual elements in the list. Example 1

[0026] like Figures 1 to 3As shown, the recirculating oil drum evaporator of this utility model includes an outer drum wall 1, an inner drum wall 2, a first end wall 3, a second end wall 4, a refrigerant inlet pipe 6, a refrigerant outlet pipe 7, a first annular baffle 8, and a second annular baffle 12. The first annular baffle 8 and the second annular baffle 12 are respectively fitted inside the two ends of the inner drum wall 2. The outer drum wall 1 surrounds the outer side of the inner drum wall 2, the first annular baffle 8, and the second annular baffle 12. The first end wall 3 is sealed to one end of both the outer drum wall 1 and the inner drum wall 2, and the second end wall 4 is sealed to the other end of both the outer drum wall 1 and the inner drum wall 2. An evaporation chamber 5 is formed between the inner barrel walls 2. The first end wall 3 and the first annular partition 8 are located on the same side of the evaporation chamber 5. A distribution chamber 9 is formed between the first end wall 3 and the first annular partition 8. The second end wall 4 and the second annular partition 12 are located on the other side of the evaporation chamber 5. An oil return chamber 10 is formed between the second end wall 4 and the second annular partition 12. The distribution chamber 9, the oil return chamber 10 and the evaporation chamber 5 are all annular cavities. The distribution chamber 9 and the oil return chamber 10 are located at the two ends of the evaporation chamber 5, respectively. The distribution chamber 9 and the oil return chamber 10 are both connected to the evaporation chamber 5. The distribution chamber 9 is connected to the refrigerant inlet pipe 6, and the oil return chamber 10 is connected to the refrigerant outlet pipe 7.

[0027] like Figure 2 and Figure 4 As shown, the refrigerant inlet pipe 6 is sealed and welded to the first end wall 3. One end of the refrigerant inlet pipe 6 is the first port 6-1, which is located on the first end wall 3 and communicates with the distribution chamber 9. The other end of the refrigerant inlet pipe 6 is the second port 6-2, which is located on the side of the first end wall 3 outside the evaporation chamber 5.

[0028] The inner ring edge of the first annular partition 8 is uniformly provided with first guide holes 8-2 for connecting the distribution chamber 9 and the evaporation chamber 5, for guiding the refrigerant flow. Each side of the first guide hole 8-2 is provided with a first limiting protrusion 8-3, which is an integral structure with the first annular partition 8. The first limiting protrusion 8-3 is a structure bent out from the first annular partition 8. The first guide holes 8-2 are notches left on the second annular partition 12 after the second limiting protrusion 12-3 is bent out. The first limiting protrusions 8-3 are spaced between the first annular partition 8 and the first end wall 3, facilitating control of the distance between the first annular partition 8 and the first end wall 3 during assembly, thus forming the distribution chamber 9 between the first annular partition 8 and the first end wall 3. The first end wall 3 is also provided with two first refrigerant outlet pipe through holes 8-1 for the passage of two refrigerant outlet pipes 7.

[0029] like Figure 3 and Figure 4As shown, the refrigerant outlet pipe 7 includes a main outlet pipe 11 and two branch outlet pipes. The branch outlet pipes are all sealed and welded to the first end wall 3. One end of each branch outlet pipe is a third outlet 7-1, and the other end is a fourth outlet 7-2. All the third outlets 7-1 are evenly distributed circumferentially on the second annular baffle 12 and are all connected to the oil return chamber 10. The two branch outlet pipes extend in the direction of the first end wall 3. All the fourth outlets 7-2 are located on the side of the first end wall 3 outside the evaporator chamber 5 and are connected to the main outlet pipe 11 for easy connection to the compressor.

[0030] like Figure 5 and Figure 6 As shown, the inner ring edge of the second annular partition 12 is uniformly provided with second guide holes 12-2 for communicating the oil return chamber 10 and the evaporation chamber 5. Each side of the second guide hole 12-2 is provided with a second limiting protrusion 12-3. The second limiting protrusion 12-3 and the second annular partition 12 are an integral structure. The second limiting protrusion 12-3 is a structure bent out from the second annular partition 12. The second guide holes 12-2 are notches left on the second annular partition 12 after the second limiting protrusion 12-3 is bent out. The second limiting protrusions 12-3 are spaced between the second annular partition 12 and the second end wall 4, facilitating control of the distance between the second annular partition 12 and the second end wall 4 during assembly, thus forming the oil return chamber 10 between the second annular partition 12 and the second end wall 4. The second limiting protrusion 12-3 is provided with a second flow guiding arc surface 12-4, which is connected to the second annular partition 12, facilitating the flow of lubricating oil into the oil return chamber 10. The structure of the second annular partition 12 can be the same as that of the first annular partition 8, which facilitates processing and reduces mold making.

[0031] The refrigerant flows from the refrigerant inlet pipe 6 into the distribution chamber 9 located at one end of the evaporation chamber 5. After being uniformly guided by the first annular baffle 8 located in the distribution chamber 9, it diffuses evenly into the evaporation chamber 5. In the evaporation chamber 5, it expands and vaporizes, absorbing heat from the outer barrel wall 1 and the inner barrel wall 2. Then it diffuses into the oil return chamber 10 located at the other end of the evaporation chamber 5. Finally, it flows back to the compressor through the refrigerant outlet pipe 7. Although the metal spiral tube has been eliminated, the lubricating oil that enters the evaporation chamber from the compressor along with the refrigerant is guided by the second annular baffle 12 of the oil return chamber 10 and enters the oil return chamber 10 through the second guide hole 12-2 to accumulate. Under the pressure difference, the lubricating oil accumulated in the oil return chamber 10 can smoothly flow back to the compressor along with the refrigerant through the refrigerant outlet pipe 7, avoiding oil shortage in the compressor.

[0032] In other embodiments, the first guide hole 8-2 may be a plurality of small holes evenly distributed on the end face of the first annular partition 8, or it may be formed by the gap between the first annular partition 8 and the inner barrel wall 2, or it may be formed by the gap between the first annular partition 8 and the outer barrel wall 1.

[0033] Since the presence or absence of the distribution cavity 9 does not affect the return flow of lubricating oil, in other embodiments, the first annular partition 8 that forms the distribution cavity 9 together with the first end wall 3 can be omitted. Example 2

[0034] The barrel-type evaporator in this embodiment simplifies the manufacturing process compared to the above embodiments. It includes an outer tube, an inner tube, and a first end plate, a second end plate, a first annular partition 8, and a second annular partition 12, all of which are annular structures. The first annular partition 8 and the second annular partition 12 are respectively welded to the inner sides of both ends of the inner tube. The outer tube and the inner tube are coaxially sleeved. The outer and inner annular edges of the first end plate are respectively sealed and welded to one end of the outer tube and the inner tube. The outer and inner annular edges of the second end plate are respectively sealed and welded to the other end of the outer tube and the inner tube. A space is formed between the outer tube and the inner tube. An annular cavity evaporator 5 is provided. An annular cavity distribution cavity 9 is formed between a first end plate and a first annular partition 8 located at one end of the evaporator 5. An annular cavity oil return cavity 10 is formed between a second end plate and a second annular partition 12 located at the other end of the evaporator 5. Both the distribution cavity 9 and the oil return cavity 10 are connected to the evaporator 5. The wall of the outer pipe forms the outer barrel wall 1, and the wall of the inner pipe forms the inner barrel wall 2. The first end plate forms the first end wall 3, and the second end plate forms the second end wall 4. The refrigerant inlet pipe 6 is connected to the distribution cavity 9, and the refrigerant outlet pipe 7 is connected to the oil return cavity 10. The structure of the first annular partition 8 and the second annular partition 12 can be the same as in Embodiment 1.

[0035] In this embodiment, the outer barrel wall 1 and the inner barrel wall 2 serve as the inner and outer side walls of the evaporation chamber 5, both of which can contact the object being cooled for heat conduction, resulting in high cooling efficiency.

[0036] The above are merely specific embodiments of this utility model and are not intended to limit the scope of implementation of this utility model. Any modifications or equivalent substitutions to this utility model without departing from its spirit and scope should be covered within the protection scope of the claims of this utility model.

Claims

1. A recirculating oil drum-type evaporator, characterized in that, It includes an outer barrel wall (1), an inner barrel wall (2), a first end wall (3), a second end wall (4), a refrigerant inlet pipe (6), a refrigerant outlet pipe (7), and a second annular partition (12). The second annular partition (12) is fitted onto the inner barrel wall (2). The outer barrel wall (1) surrounds the outer side of the inner barrel wall (2) and the second annular partition (12). The first end wall (3) is sealed to one end of both the outer barrel wall (1) and the inner barrel wall (2). The second end wall (4) is sealed to the other end of both the outer barrel wall (1) and the inner barrel wall (2). An evaporation chamber (5) is formed between the second annular partition (12) and the second end wall (4). An oil return chamber (10) is formed between the second annular partition (12) and the second end wall (4). Both the evaporation chamber (5) and the oil return chamber (10) are annular cavities. The oil return chamber (10) is located at one end of the evaporation chamber (5). The second annular partition (12) is provided with a second guide hole (12-2) for connecting the oil return chamber (10) and the evaporation chamber (5). The oil return chamber (10) is connected to at least one refrigerant outlet pipe (7). The other end of the evaporation chamber (5) is connected to at least one refrigerant inlet pipe (6).

2. The recirculating oil drum evaporator according to claim 1, characterized in that, One end of the refrigerant outlet pipe (7) is the third outlet (7-1), which is located on the second annular baffle (12) and communicates with the oil return chamber (10). The refrigerant outlet pipe (7) extends in the direction of the first end wall (3). The other end of the refrigerant outlet pipe (7) is the fourth outlet (7-2), which is located on the side of the first end wall (3) outside the evaporation chamber (5).

3. The recirculating oil drum evaporator according to claim 1, characterized in that, The inner barrel wall (2) is also fitted with a first annular partition (8), and the outer barrel wall (1) surrounds the outside of the first annular partition (8). A distribution cavity (9) is formed between the first annular partition (8) and the first end wall (3). The distribution cavity (9) is an annular cavity. The first annular partition (8) is provided with a first guide hole (8-2) for connecting the distribution cavity (9) with the evaporation cavity (5). One end of the refrigerant inlet pipe (6) is the first pipe port (6-1). The first pipe port (6-1) is located on the first end wall (3) and is connected to the distribution cavity (9). The other end of the refrigerant inlet pipe (6) is the second pipe port (6-2). The second pipe port (6-2) is located on the side of the first end wall (3) outside the evaporation cavity (5).

4. The recirculating oil drum evaporator according to claim 2, characterized in that, The refrigerant outlet pipe (7) includes a main outlet pipe (11) and multiple outlet branch pipes. One end of the outlet branch pipe is a third outlet (7-1), and the other end is a fourth outlet (7-2). All the third outlets (7-1) are evenly distributed circumferentially on the second annular baffle (12) and are all connected to the oil return chamber (10). All the fourth outlets (7-2) are connected to the main outlet pipe (11).

5. The recirculating oil drum evaporator according to claim 2, characterized in that, A plurality of second limiting protrusions (12-3) are provided between the second annular partition (12) and the second end wall (4). The second annular partition (12) and the second end wall (4) are respectively limited on both sides of the second limiting protrusions (12-3), so that an oil return cavity (10) is formed between the second annular partition (12) and the second end wall (4).

6. The recirculating oil drum evaporator according to claim 5, characterized in that, The second limiting protrusion (12-3) and the second annular partition (12) are an integral structure. The second limiting protrusion (12-3) is a structure that bends out from the second annular partition (12). There are several second guide holes (12-2), and they are all small holes or notches left on the second annular partition (12) after the second limiting protrusion (12-3) is bent out.

7. The recirculating oil drum evaporator according to claim 6, characterized in that, The second limiting protrusion (12-3) is provided with a second flow guiding arc surface (12-4), which is connected to the second annular partition (12).

8. The oil return tank-type evaporator according to claim 3, characterized in that, The first guide hole (8-2) is a number of small holes evenly distributed on the end face of the first annular partition (8), or a number of notches evenly distributed on the inner ring edge of the first annular partition (8).

9. The recirculating oil drum evaporator according to claim 3, characterized in that, The first guide hole (8-2) is formed by the gap between the first annular partition (8) and the inner barrel wall (2) and / or the gap between the first annular partition (8) and the outer barrel wall (1).

10. The recirculating oil drum evaporator according to claim 1, characterized in that, The system includes an outer tube, an inner tube, and a first end plate, a second end plate, a first annular partition (8), and a second annular partition (12), all of which are annular structures. The first annular partition (8) and the second annular partition (12) are welded to the inner sides of both ends of the inner tube, respectively. The outer tube and the inner tube are coaxially sleeved together. The outer and inner annular edges of the first end plate are sealed and welded to one end of the outer tube and the inner tube, respectively. The outer and inner annular edges of the second end plate are sealed and welded to the other end of the outer tube and the inner tube, respectively. An annular cavity evaporation chamber (5) is formed between the outer tube and the inner tube. The first end plate is located at one end of the evaporation chamber (5). An annular cavity distribution chamber (9) is formed between the end plate and the first annular partition (8), and an annular cavity return oil chamber (10) is formed between the second end plate and the second annular partition (12) located at the other end of the evaporation chamber (5). Both the distribution chamber (9) and the return oil chamber (10) are connected to the evaporation chamber (5). The pipe wall of the outer pipe constitutes the outer barrel wall (1), the pipe wall of the inner pipe constitutes the inner barrel wall (2), the first end plate constitutes the first end wall (3), the second end plate constitutes the second end wall (4), the refrigerant inlet pipe (6) is connected to the distribution chamber (9), and the refrigerant outlet pipe (7) is connected to the return oil chamber (10).

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