Anti-suckback mechanism for a rotary evaporator

Abstract

This invention belongs to the field of evaporator technology and discloses an anti-backflow mechanism for a rotary evaporator. The mechanism includes a base, a lifting rod fixedly installed at the rear end of the top center of the base, a rotating shaft fixedly installed on the front of the lifting rod, a condenser tube fixedly installed on the left side of the rotating shaft, a recovery bottle movably installed at the bottom of the condenser tube, and a backflow storage box fixedly installed at the left end of the top of the base. A connecting port and a connecting pipe are fixedly installed at the left and right ends of the top of the backflow storage box, respectively. This invention achieves the anti-backflow purpose by incorporating limit blocks, air bladders, and third springs. When the vacuum pump stops working due to power failure, the pressure inside the condenser tube is relatively high, causing the two third springs to reset, preventing the circulating water from the vacuum pump from being drawn back into the condenser tube. The circulating water inside the vacuum pump will then enter the backflow storage box for collection, thus achieving the anti-backflow effect.

Description

Technical Field

[0001] This invention belongs to the field of evaporator technology, specifically an anti-backflow mechanism for rotary evaporators. Background Technology

[0002] A rotary evaporator, also known as a rotary evaporator, is a widely used evaporation instrument in laboratories. It consists of a motor, distillation flask, heating pot, condenser, and other components. Rotary evaporators are currently mainly used in the chemical, pharmaceutical, food, and biological industries. The vacuum inside the rotary evaporator is achieved by evacuating the evaporator with a circulating water pump. This method has certain safety hazards. If the water pump stops working accidentally during the vacuuming process due to power failure, mechanical failure, or human error, the wastewater in the water pump will be quickly sucked back into the rotary evaporator due to the vacuum inside. Since it does not have any anti-backflow device, it can lead to contamination of the concentrated product or even an explosion.

[0003] The invention patent with patent number CN201910205213.0 provides a rotary evaporator. The problem solved by this patent is that in the prior art, during the vacuuming process of the solvent bottle in the rotary evaporator, the solvent in the solvent bottle is prone to boiling violently, which causes the solvent to overflow into the recovery bottle and contaminate the recovery bottle. The improved structure is very simple. It divides the recovery bottle into multiple recovery zones by designing a partition, and then recovers the solvent into different recovery bottles through the flow guide connector. After the solvent in the solvent bottle boils violently, it prevents the recovered solvent from contaminating the solvent in the adjacent recovery zone, and finally achieves the purpose of avoiding overflow. The design of this device is too simple.

[0004] The utility model patent with patent number CN201922090372.9 provides a rotary evaporator with anti-backflow protection. The problem solved by this patent is that when the distillation flask of the existing rotary evaporator is completely evaporated and heating is stopped, the negative pressure caused by the cessation of heating can easily lead to backflow of steam or backflow of liquid after steam liquefaction. The improvement is very simple. By setting a check plate at the top of the distillation flask, the purpose of preventing backflow is finally achieved. However, the design of this device is too simple.

[0005] In existing rotary evaporators, the vacuum process can be disrupted by factors such as power outages, mechanical failures, or human error, causing the vacuum to stop working. At this point, the evaporator body is under negative pressure, and the circulating liquid in the vacuum pump will be quickly drawn back into the distillation chamber, contaminating the experimental materials and causing the experiment to fail. This requires the experimental materials to be taken again, and the interior of the rotary evaporator needs to be cleaned, which increases the time and cost of the experiment and reduces the efficiency of the experiment. Summary of the Invention

[0006] To address the problems mentioned in the background section, this invention provides an anti-backflow mechanism for a rotary evaporator, which has the advantages of preventing backflow, facilitating disassembly and assembly, and automatically draining backflowed water.

[0007] To achieve the above objectives, the present invention provides the following technical solution: an anti-backflow mechanism for a rotary evaporator, comprising a base, a lifting rod fixedly installed at the rear end of the top center of the base, a rotating shaft fixedly installed on the front of the lifting rod, a condenser tube fixedly installed on the left side of the rotating shaft, a recovery bottle movably installed at the bottom of the condenser tube, a backflow storage box fixedly installed at the left end of the top of the base, a connecting port and a connecting pipe fixedly installed at the left and right ends of the top of the backflow storage box, a limiting block fixedly installed in the middle of the inside of the connecting pipe, a fixing post movably sleeved in the middle of the limiting block, a third sealing block movably sleeved at the upper end of the fixing post, an air bladder fixedly installed at the outer end of the top of the third sealing block, a lower sealing block fixedly installed at the bottom of the fixing post, and a third spring fixedly sleeved at both ends of the upper end of the fixing post.

[0008] In the above technical solution, preferably, a connecting pipe is fixedly installed at the top of the condenser tube, a docking ring is fixedly installed at the bottom of the left end of the connecting pipe, a fixing ring is fixedly installed at the middle of the inner side of the docking ring, a sealing ring is fixedly installed inside the outer wall of the docking ring, fixing grooves are respectively opened at the left and right ends of the outer side of the docking ring, fixing blocks are fixedly installed at the left and right ends of the upper end of the docking tube, and a snap-fit ​​groove is opened at the top of the docking tube.

[0009] In the above technical solution, preferably, a transmission column is fixedly installed at the bottom of the lower sealing block, a fixing plate is fixedly installed in the middle of the inside of the back suction storage box, a receiving block is fixedly installed at the bottom of the right end of the fixing plate, a second spring is fixedly installed at the top of the receiving block, a second sealing block is fixedly installed at the top of the second spring, an outlet is fixedly installed at the lower left end of the back suction storage box, a fixing block is fixedly installed at the left end inside the outlet, a first spring is fixedly installed at the right side of the fixing block, and a first sealing block is fixedly installed at the right side of the first spring.

[0010] In the above technical solution, preferably, the top of the fixing column is fixedly installed with the top of the airbag inside, the airbag is made of rubber material, and the outer diameter of the airbag is consistent with the inner upper diameter of the connecting pipe.

[0011] In the above technical solution, preferably, the top of the upper third spring is fixedly installed at the bottom of the third sealing block, and the inner sides of the two third springs are respectively fixedly installed at the top and bottom of the limiting block.

[0012] In the above technical solution, preferably, a sealing gasket is fixedly installed on the outer end of the top of the lower sealing block, the lower sealing block is located at the top inside the back suction storage box, a circular groove is opened in the middle of the inside of the connecting pipe, and the diameter of the third sealing block is smaller than the diameter of the circular groove and larger than the diameter of the inside of the connecting pipe.

[0013] In the above technical solution, preferably, the two fixing grooves are L-shaped, the fixing ring is movably engaged inside the locking groove, and rubber pads are fixedly installed on the inner and outer walls of the locking groove respectively.

[0014] In the above technical solution, preferably, the two fixing blocks are movably engaged inside the two fixing grooves, and the sealing ring is made of rubber.

[0015] In the above technical solution, preferably, the second sealing block is located at the bottom of the fixing plate and at the top of the receiving block, and the diameter of the transmission column is smaller than the diameter of the second sealing block.

[0016] In the above technical solution, preferably, the diameter of the fixing block is smaller than the diameter of the inner side of the outlet, and a second circular groove is provided at the right end of the inner side of the outlet. The diameter of the first sealing block is smaller than the second circular groove and larger than the diameter of the inner side of the outlet.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] 1. This invention achieves the purpose of preventing backflow by setting a limit block, an air bladder, and a third spring. When the vacuum pump stops working due to power failure, the pressure inside the condenser tube is relatively high, and the two third springs will reset. At the same time, they will drive the fixed column and the third sealing block to move upward to seal the inside of the connecting pipe. Meanwhile, the top of the fixed column will push the air bladder to seal the inside of the connecting pipe, preventing the vacuum pump circulating water from being sucked back into the condenser tube. The circulating water inside the vacuum pump will enter the backflow storage tank for collection, thus achieving the effect of preventing backflow.

[0019] 2. This invention achieves the purpose of easy assembly and disassembly by setting a docking ring, a fixing ring, and a sealing ring. The bottom of the right end of the connecting pipe is connected to the inside of the condenser pipe. The docking ring is respectively fitted onto two fixing blocks through two fixing grooves. The fixing ring is fitted into the inside of the snap-fit ​​groove. The inside of the connecting pipe is sealed by the rubber gaskets on the inner and outer walls of the snap-fit ​​groove. The docking ring is rotated and the connecting pipe is fixed by the two fixing blocks, thus achieving the effect of easy assembly and disassembly.

[0020] 3. This invention achieves the purpose of automatic drainage of back-suction water by setting up an outlet, receiving block, and transmission column. After the vacuum pump stops working, the circulating water inside the vacuum pump enters the interior of the back-suction storage tank through the interface. While the lower sealing block moves upward, it pushes the transmission column downward. The bottom of the transmission column pushes the second sealing block. At this time, the water at the upper end of the back-suction storage tank will fall into the lower end of the back-suction storage tank through the top of the second sealing block. After the vacuum pump stops working, the first spring will return to its original position, driving the first sealing block to move to the left. At this time, the water at the lower end of the back-suction storage tank will be discharged through the outlet, thus achieving the effect of automatic drainage of back-suction water. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall appearance of the structure of the present invention;

[0022] Figure 2 This is a schematic diagram of the external appearance of the condenser tube of the present invention;

[0023] Figure 3 This is a schematic diagram of the external appearance of the inverted suction storage box of the present invention;

[0024] Figure 4 This is a front cross-sectional view of the inverted suction storage box of the present invention;

[0025] Figure 5 The structure of this invention Figure 4 Enlarged view of point A;

[0026] Figure 6 This is a schematic cross-sectional view of the front end of the inverted suction storage box of the present invention;

[0027] Figure 7 The structure of this invention Figure 6 Enlarged view of point B;

[0028] Figure 8 This is a bottom view of the docking ring structure of the present invention.

[0029] In the diagram: 1. Base; 2. Recycling bottle; 3. Lifting rod; 4. First spring; 5. First sealing block; 6. Rotating shaft; 7. Condenser pipe; 8. Connecting pipe; 9. Fixing block; 10. Connecting pipe; 11. Connecting interface; 12. Back suction storage box; 13. Discharge port; 14. Connecting ring; 15. Fixing groove; 16. Fixing ring; 17. Sealing ring; 18. Fixing plate; 19. Receiving block; 20. Second spring; 21. Second sealing block; 22. Transmission column; 23. Snap-fit ​​groove; 24. Fixing block; 25. Airbag; 26. Third sealing block; 27. Limiting block; 28. Third spring; 29. ​​Lower sealing block; 30. Fixing column. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] like Figures 1 to 8 As shown, the present invention provides an anti-backflow mechanism for a rotary evaporator, including a base 1, a lifting rod 3 fixedly installed at the rear end of the top center of the base 1, a rotating shaft 6 fixedly installed on the front of the lifting rod 3, a condenser tube 7 fixedly installed on the left side of the rotating shaft 6, a recovery bottle 2 movably installed at the bottom of the condenser tube 7, a backflow storage box 12 fixedly installed at the left end of the top of the base 1, a connecting port 11 and a connecting pipe 10 fixedly installed at the left and right ends of the top of the backflow storage box 12, a limiting block 27 fixedly installed in the middle of the inside of the connecting pipe 10, a fixing post 30 movably sleeved in the middle of the limiting block 27, a third sealing block 26 movably sleeved at the upper end of the fixing post 30, an airbag 25 fixedly installed at the outer end of the top of the third sealing block 26, a lower sealing block 29 fixedly installed at the bottom of the fixing post 30, and a third spring 28 fixedly sleeved at both ends of the upper end of the fixing post 30.

[0032] By connecting the vacuum pump to the interface 11, the inside of the back suction storage tank 12 is evacuated through the interface 11, and the inside of the condenser tube 7 is evacuated through the connecting pipe 10. After the vacuum pump suddenly stops working due to power failure, the pressure inside the condenser tube 7 is relatively high. The two third springs 28 will drive the lower sealing block 29 and the third sealing block 26 to move upward to seal the inside of the connecting pipe 10, thus preventing the vacuum pump circulating water from entering the inside of the condenser tube 7.

[0033] like Figure 3 , 5 As shown in Figure 8, a connecting pipe 8 is fixedly installed on the top of the condenser pipe 7, a docking ring 14 is fixedly installed on the bottom of the left end of the connecting pipe 8, a fixing ring 16 is fixedly installed on the middle of the inner side of the docking ring 14, a sealing ring 17 is fixedly installed on the inner side of the outer wall of the docking ring 14, a fixing groove 15 is opened on the left and right ends of the outer side of the docking ring 14, a fixing block 24 is fixedly installed on the left and right ends of the upper end of the connecting pipe 10, and a snap-fit ​​groove 23 is opened on the top of the connecting pipe 10.

[0034] The above scheme is adopted: the inside of the connecting pipe 8 is sealed by snapping the bottom left end of the connecting pipe 8 with the upper end of the connecting pipe 10, and the two fixing blocks 24 are respectively snapped into the inside of the two fixing grooves 15. While rotating the connecting ring 14 and fixing the connecting ring 14 with the two fixing blocks 24, the sealing ring 17 seals the connecting ring 14 and the connecting pipe 10.

[0035] like Figure 4 , 6 As shown in Figure 7, a transmission column 22 is fixedly installed at the bottom of the lower sealing block 29, a fixing plate 18 is fixedly installed in the middle of the inside of the back suction storage box 12, a receiving block 19 is fixedly installed at the bottom of the right end of the fixing plate 18, a second spring 20 is fixedly installed at the top of the receiving block 19, a second sealing block 21 is fixedly installed at the top of the second spring 20, an outlet 13 is fixedly installed at the lower left end of the back suction storage box 12, a fixing block 9 is fixedly installed at the left end inside the outlet 13, a first spring 4 is fixedly installed at the right side of the fixing block 9, and a first sealing block 5 is fixedly installed at the right side of the first spring 4.

[0036] Using the above scheme: when the vacuum pump evacuates the inside of the rotary evaporator condenser tube 7, the lower sealing block 29 will move downward, driving the transmission column 22 to move downward, which will push the second sealing block 21 downward, and the second spring 20 will be compressed. At this time, the water at the upper end of the back suction storage tank 12 will fall into the lower end of the back suction storage tank 12 through the upper end of the receiving block 19, and at the same time, the inside of the back suction storage tank 12 will be sealed by the first sealing block 5.

[0037] like Figure 4 , 5 As shown, the top of the fixing column 30 is fixedly installed with the top of the inside of the airbag 25. The airbag 25 is made of rubber material, and the outer diameter of the airbag 25 is the same as the inner upper diameter of the connecting tube 10.

[0038] The above solution is adopted: the air bag 25 seals the inside of the connecting pipe 10. When the vacuum pump suddenly loses power while evacuating the rotary evaporator, the pressure inside the condenser tube 7 is relatively high. The two third springs 28 will reset and push the fixed column 30 and the third sealing block 26 upward to seal the inside of the connecting pipe 10. At the same time, the top of the fixed column 30 will push the air bag 25 upward to seal the upper end of the inside of the connecting pipe 10.

[0039] like Figure 4 , 5 As shown, the top of the upper third spring 28 is fixedly installed at the bottom of the third sealing block 26, and the inner sides of the two third springs 28 are fixedly installed at the top and bottom of the limiting block 27 respectively.

[0040] Using the above scheme: the upper third spring 28 pushes the third sealing block 26 upward. When the pressure inside the condenser tube 7 is greater than the pressure inside the backflow storage tank 12, the two third springs 28 will reset and simultaneously push the third sealing block 26 to seal the inside of the connecting pipe 10.

[0041] like Figure 1 , 4As shown in Figure 5, a sealing gasket is fixedly installed on the outer end of the top of the lower sealing block 29. The lower sealing block 29 is located at the top inside the back suction storage box 12. A circular slot is opened in the middle of the inside of the connecting pipe 10. The diameter of the third sealing block 26 is smaller than the diameter of the circular slot and larger than the diameter of the inside of the connecting pipe 10.

[0042] The above scheme is adopted: the lower sealing block 29 is snapped into the top of the inside of the back suction storage box 12 to limit the fixed column 30 and the third sealing block 26. The sealing gasket at the top of the lower sealing block 29 seals the inside of the connecting pipe 10 again. When the third sealing block 26 is at the top of the first circular slot, the inside of the connecting pipe 10 is sealed. When the third sealing block 26 is in the middle of the first circular slot, the connecting pipe 10 will be opened.

[0043] like Figure 3 , 5 As shown in Figure 8, the two fixing grooves 15 are L-shaped, and the fixing ring 16 is movably engaged inside the locking groove 23. Rubber pads are fixedly installed on the inner and outer walls of the locking groove 23 respectively.

[0044] The above solution is adopted: by movably engaging the two fixing blocks 24 into the interior of the two fixing grooves 15 respectively, and then fixing the docking ring 14 by rotating the docking ring 14, the fixing ring 16 will be engaged into the interior of the engagement groove 23, and the rubber pads on the inner and outer walls of the engagement groove 23 will contact the inner and outer sides of the fixing ring 16 to seal the interior of the docking ring 14.

[0045] like Figure 3 , 4 As shown in Figures 5 and 8, the two fixing blocks 24 are respectively movably engaged inside the two fixing grooves 15, and the sealing ring 17 is made of rubber.

[0046] The above solution is adopted: two fixing blocks 24 are snapped into the inside of two fixing grooves 15, the rotating docking ring 14 is fixed to the fixing groove 15 by the fixing blocks 24, and the gap between the docking ring 14 and the docking tube 10 is sealed by the sealing ring 17.

[0047] like Figure 4 , 6 As shown, the second sealing block 21 is located at the bottom of the fixing plate 18 and at the top of the receiving block 19, and the diameter of the transmission column 22 is smaller than the diameter of the second sealing block 21.

[0048] Using the above scheme: the lower sealing block 29 moves downward, driving the transmission column 22 to move downward. The bottom of the transmission column 22 will push the second sealing block 21 to squeeze the second spring 20. The vacuum pump at the upper end of the back suction storage box 12 will back suction water through the upper end of the receiving block 19 into the lower end of the back suction storage box 12, and then discharge it through the outlet 13.

[0049] like Figure 6 , 7 As shown, the diameter of the fixing block 9 is smaller than the diameter of the inner side of the outlet 13. A second circular groove is provided at the right end of the inner side of the outlet 13. The diameter of the first sealing block 5 is smaller than the diameter of the second circular groove and larger than the diameter of the inner side of the outlet 13.

[0050] Using the above scheme: When the rotary evaporator is evacuated by the vacuum pump, the lower sealing block 29 will push the transmission column 22 to move downward, and at the same time the second sealing block 21 will move downward. At this time, the first sealing block 5 will be located on the right side of the outlet 13 to seal the inside of the backflow storage tank 12. The first spring 4 will be stretched. When the vacuum pump is suddenly de-energized, the first spring 4 will reset and pull the first sealing block 5, and the water inside the backflow storage tank 12 will be discharged through the outlet 13.

[0051] Working principle and usage process of this invention:

[0052] First, attach the heating flask to the right end of the rotating shaft 6. Adjust the rotating shaft 6 to a suitable height so that the heating flask is inside the water bath. Connect the bottom of the right end of the connecting pipe 8 to the inside of the condenser pipe 7. Then, attach the docking ring 14 to the two fixing blocks 24 via the two fixing slots 15. The fixing ring 16 will be fitted into the snap-fit ​​groove 23. The rubber gaskets on the inner and outer walls of the snap-fit ​​groove 23 seal the inside of the connecting pipe 8. Rotate the docking ring 14 and fix the connecting pipe 8 using the two fixing blocks 24. Finally, connect the vacuum pump to the docking port 11. The rotating shaft 6 drives the heating bottle to rotate, and at the same time, the vacuum pump will be started to evacuate the inside of the heating bottle. The vacuum pump will evacuate the inside of the back suction storage box 12 through the interface 11. When the pressure inside the back suction storage box 12 is large, the lower sealing block 29 will move downward, and the two third springs 28 will be compressed. The third sealing block 26 will slide downward through the fixed column 30, and the air bag 25 will disengage from the upper end of the connecting pipe 10. At this time, the inside of the condenser tube 7 will be evacuated through the connecting pipe 8. The heating bottle is connected to the inside of the condenser tube 7 through the rotating shaft 6.

[0053] When the vacuum pump stops working due to power failure, the pressure inside the condenser tube 7 is relatively high, and the two third springs 28 will reset. At the same time, they will drive the fixed column 30 and the third sealing block 26 to move upward to seal the inside of the connecting pipe 10. Simultaneously, the top of the fixed column 30 will push the air bag 25 to seal the inside of the connecting pipe 10, preventing the vacuum pump circulating water from being sucked back into the condenser tube 7. The circulating water inside the vacuum pump will enter the backflow storage tank 12 for collection. As the lower sealing block 29 moves upward, it pushes the transmission column 22 to move downward. The bottom of the transmission column 22 will push the second sealing block 21. At this time, the water at the upper end of the backflow storage tank 12 will fall into the lower end of the backflow storage tank 12 through the top of the second sealing block 21. After the vacuum pump stops working, the first spring 4 will reset, driving the first sealing block 5 to move to the left. At this time, the water at the lower end of the backflow storage tank 12 will be discharged through the outlet 13.

[0054] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0055] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An anti-backflow mechanism for a rotary evaporator, comprising a base (1), characterized in that: A lifting rod (3) is fixedly installed at the rear end of the top center of the base (1). A rotating shaft (6) is fixedly installed on the front of the lifting rod (3). A condenser pipe (7) is fixedly installed on the left side of the rotating shaft (6). A recycling bottle (2) is movably installed at the bottom of the condenser pipe (7). A backflow storage box (12) is fixedly installed at the left end of the top of the base (1). A connecting port (11) and a connecting pipe (10) are fixedly installed at the left and right ends of the top of the backflow storage box (12), respectively. The middle part of the inside of the connecting pipe (10) A limiting block (27) is fixedly installed. A fixed post (30) is movably sleeved in the middle of the limiting block (27). A third sealing block (26) is movably sleeved at the upper end of the fixed post (30). An airbag (25) is fixedly installed at the outer end of the top of the third sealing block (26). A lower sealing block (29) is fixedly installed at the bottom of the fixed post (30). A third spring (28) is fixedly sleeved at both ends of the upper end of the fixed post (30). A transmission post (22) is fixedly installed at the bottom of the lower sealing block (29). A fixing plate (18) is fixedly installed in the middle of the inside of the suction storage box (12). A receiving block (19) is fixedly installed at the bottom right end of the fixing plate (18). A second spring (20) is fixedly installed on the top of the receiving block (19). A second sealing block (21) is fixedly installed on the top of the second spring (20). A discharge port (13) is fixedly installed at the lower left side of the suction storage box (12). A fixing block (9) is fixedly installed at the left end inside the discharge port (13). A fixing block (9) is fixedly installed on the right side of the fixing block (9). There is a first spring (4), and a first sealing block (5) is fixedly installed on the right side of the first spring (4); the second sealing block (21) is located at the bottom of the fixing plate (18) and at the top of the receiving block (19), and the diameter of the transmission column (22) is smaller than the diameter of the second sealing block (21); the top of the fixing column (30) is fixedly installed with the top of the inside of the airbag (25), the airbag (25) is made of rubber, and the outer diameter of the airbag (25) is consistent with the inner upper diameter of the connecting pipe (10).

2. The anti-backflow mechanism for a rotary evaporator according to claim 1, characterized in that: A connecting pipe (8) is fixedly installed on the top of the condenser pipe (7). A docking ring (14) is fixedly installed at the bottom of the left end of the connecting pipe (8). A fixing ring (16) is fixedly installed in the middle of the inner side of the docking ring (14). A sealing ring (17) is fixedly installed inside the outer wall of the docking ring (14). Fixing grooves (15) are respectively opened at the left and right ends of the outer side of the docking ring (14). Fixing blocks (24) are fixedly installed at the left and right ends of the upper end of the connecting pipe (10). A snap-fit ​​groove (23) is opened at the top of the connecting pipe (10).

3. The anti-backflow mechanism for a rotary evaporator according to claim 1, characterized in that: The top of the upper third spring (28) is fixedly installed at the bottom of the third sealing block (26), and the inner sides of the two third springs (28) are respectively fixedly installed at the top and bottom of the limiting block (27).

4. The anti-backflow mechanism for a rotary evaporator according to claim 1, characterized in that: A sealing gasket is fixedly installed on the outer end of the top of the lower sealing block (29). The lower sealing block (29) is located at the top inside the back suction storage box (12). A circular slot is opened in the middle of the inside of the connecting pipe (10). The diameter of the third sealing block (26) is smaller than the diameter of the circular slot and larger than the diameter of the inside of the connecting pipe (10).

5. The anti-backflow mechanism for a rotary evaporator according to claim 2, characterized in that: The two fixing grooves (15) are L-shaped, and the fixing ring (16) is movably engaged inside the locking groove (23). Rubber pads are fixedly installed on the inner and outer walls of the locking groove (23).

6. The anti-backflow mechanism for a rotary evaporator according to claim 2, characterized in that: The two fixing blocks (24) are respectively movably engaged inside the two fixing grooves (15), and the sealing ring (17) is made of rubber.

7. The anti-backflow mechanism for a rotary evaporator according to claim 1, characterized in that: The diameter of the fixing block (9) is smaller than the diameter of the inner side of the outlet (13), and a second circle is opened at the right end of the inner side of the outlet (13). The diameter of the first sealing block (5) is smaller than that of the second circular slot and larger than that of the inner side of the outlet (13).

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