Protection monitoring connection structure of pressure sensor
By using a grip connection structure between the pressure sensor protective cover and the monitoring head, the liquid overflow problem caused by loose protective cover in the prior art is solved, and the operation process is simplified, improving safety and convenience.
Patent Information
- Application Number
- CN202421983151.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-15
- Publication Date
- 2025-05-27
- Estimated Expiration
- 2034-08-15
AI Technical Summary
The protective cover of existing pressure sensors has a risk of loosening, causing liquid overflow, affecting safety, and the loosening operation is complicated, increasing the difficulty of replacing consumables and inconvenient operation.
The gripping connection structure between the protective cover and the monitoring head is adopted to achieve a fixed connection through the design of the hook and the slot to avoid the risk of loosening of the threaded connection, and to replace the screw operation through push-pull operation, simplifying the operation process.
Improves the safety of the pressure sensor protective cover, prevents liquid overflow, enhances operation convenience, and simplifies the consumable replacement process.
Smart Images
Figure CN222912962U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of medical equipment, in particular to a protection monitoring connection structure of a pressure sensor. Background Art
[0002] During blood purification treatment, arterial pressure and venous pressure need to be continuously monitored to ensure that the patient's treatment is stable. The pressure sensor is the main component for monitoring the pressure of the pipeline system during blood purification treatment. It is usually located inside the dialysis machine. The arterial pressure and venous pressure are monitored at the arterial pot and venous pot of the extracorporeal circulation pipeline respectively. The pressure sensor of the patient's extracorporeal circulation blood system and the dialysis machine is connected through a side branch on the arterial pot or venous pot. There is a pressure sensor protective cover at the end of the pipeline side branch. The protective cover has a breathable and water-tight filter membrane that can separate the liquid in the pipeline (pre-filled liquid, blood, etc.) from the pressure sensor to keep the pressure sensor dry. If the filter membrane in the protective cover is soaked with liquid, the gas transmission is hindered, and the pressure sensor will be affected, and a new protective cover needs to be replaced in time.
[0003] The protective cover of the existing pressure sensor is a gyroscopic structure with threaded structures at both ends. One section of the threaded structure is connected to the side branch of the external circulation pipeline, and the other section of the threaded structure is connected to the pressure monitoring port of the dialysis machine. The threaded structure has the risk of loosening. When the protective cover is loose, liquid will overflow to the outside of the extracorporeal circulation pipeline, resulting in serious adverse consequences and no guarantee of safety. Moreover, if the threaded structure encounters an emergency situation such as the need to replace consumables during treatment, the loosening action will increase the difficulty of removing the protective cover, delay the time for replacing consumables, and the operation is extremely inconvenient.
[0004] Therefore, how to improve the safety and operational convenience of the pressure sensor protective cover is a technical problem that needs to be solved by those skilled in the art. Utility Model Content
[0005] The utility model aims to provide a protection monitoring connection structure of a pressure sensor, which solves the technical problem that the safety and operation convenience of the pressure sensor protection cover are both poor.
[0006] To achieve the above-mentioned purpose, the utility model provides a protection monitoring connection structure of a pressure sensor, which includes a protection cover and a monitoring head, a connecting tube is fixedly provided at one end of the protection cover, and a card groove is provided on the outer side of the connecting tube; a docking tube is fixedly provided at one end of the monitoring head, and at least one hook claw is hinged on the outer side of the docking tube; when the connecting tube is docked with the docking tube, all the hook claws are retracted along the radial direction of the docking tube until they are stuck in the card groove.
[0007] Preferably, one end of the connecting tube is slidably provided with a push plate, and the push plate is fixed with at least one push rod extending along the axial direction of the connecting tube; the butt joint tube is slidably provided with an expansion plate, and all the hooks are radially against the expansion plate; when all the push rods push the expansion plate to move away from the protective cover under the drive of the push plate, the expansion plate is used to push all the hooks to expand radially along the butt joint tube until they are out of the slot.
[0008] Preferably, one end of the connecting tube is slidably provided with a push plate, and the push plate is fixed with at least one push rod extending along the axial direction of the connecting tube; the butt joint tube is slidably provided with an expansion plate, and all the hook claws are radially against the expansion plate; when all the push rods push the expansion plate to move away from the protective cover under the drive of the push plate, the expansion plate is used to push all the hook claws to expand radially along the butt joint tube until they are out of the slot.
[0009] Preferably, the monitoring head includes a fixed elastic ring, through which all the hooks pass; when all the hooks expand radially, all the hooks squeeze the elastic ring radially along the docking tube; when the push rod is separated from the expansion plate, the elastic ring is used to push all the hooks to retract radially by restoring elastic deformation.
[0010] Preferably, the monitoring head further comprises an outer cover shell which is arranged outside all the hook claws, an inner side wall of the outer cover shell is provided with an annular fixing groove, and the elastic ring is fixed in the annular fixing groove.
[0011] Preferably, the monitoring head further comprises a fixing plate, and all the hooks are hingedly connected to the fixing plate via a hinge shaft; the hinge shaft sleeve is provided with a reset torsion spring respectively abutting against the hooks and the fixing plate.
[0012] Preferably, the expansion plate is fixed with at least one push groove cooperating with the hook claw, and the hook claw is provided with a limiting tooth; when the hook claw is inserted into the slot, the limiting tooth is used to abut against the groove edge of the push groove to limit the expansion plate from excessively moving toward the protective cover.
[0013] Preferably, an opening for inserting the connecting pipe is provided at one end of the outer cover shell, and a limiting ring is integrally formed along the inner side of the opening, and the limiting ring is used to limit the elastic ring from detaching from all the hook claws.
[0014] Preferably, the protective cover comprises a cover body coaxially connected to the connecting pipe, a filter membrane is arranged in the cover body; and the diameter of the push plate is larger than the diameter of the cover body.
[0015] Preferably, a sealing ring is provided on the inner side wall of the connecting pipe; when the connecting pipe is butt-connected with the butt-joint pipe, the sealing ring abuts between the connecting pipe and the butt-joint pipe.
[0016] Preferably, one end of the butt joint pipe facing the connecting pipe is a conical structure.
[0017] Compared with the background technology, the protection monitoring connection structure of the pressure sensor in the utility model includes a protective cover and a monitoring head. A connecting pipe is fixedly provided at one end of the protective cover, and a docking tube is fixedly provided at one end of the monitoring head. A card groove is provided on the outer side of the connecting tube, and at least one hook claw is hinged on the outer side of the docking tube. When the connecting tube is docked with the docking tube, all the hook claws are retracted along the radial direction of the docking tube until they are stuck in the card groove, so that the protective cover and the monitoring head are fixedly connected.
[0018] The utility model optimizes the connection mode between the protective cover and the monitoring head, changing the original threaded connection to a grip connection, avoiding the loosening of the threaded connection, and preventing the liquid from accidentally overflowing through the protective cover to the outside of the extracorporeal circulation pipeline, which is safer; moreover, the utility model can replace the complex screwing operation with a simple push-pull operation, which is more convenient to operate and increases the convenience of operation. Therefore, the safety and convenience of operation of the protective monitoring connection structure in the utility model are both high. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.
[0020] Figure 1 A state diagram of the protection monitoring connection structure of the pressure sensor provided by the embodiment of the utility model when the protection cover is connected to the monitoring head;
[0021] Figure 2 for Figure 1 Assembly diagram of the protective cover and the monitoring head when the middle hook is inserted into the slot;
[0022] Figure 3 for Figure 1 Axonometric section view of the middle protective cover;
[0023] Figure 4 for Figure 1 A front sectional view of the middle protective cover;
[0024] Figure 5 for Figure 1 Axonometric section view of the middle monitoring head;
[0025] Figure 6 for Figure 1 Main cross-sectional view of the middle monitoring head;
[0026] Figure 7 for Figure 1 Assembly diagram of the internal components of the monitoring head;
[0027] Figure 8 is Figure 1 the exploded view of the middle claw and the fixing plate;
[0028] Figure 9 is the state diagram of the protection monitoring connection structure of the pressure sensor provided by the embodiment of the present invention when the protective cover and the monitoring head are separated;
[0029] Figure 10 is Figure 2 the front view cross-sectional view of the middle monitoring head.
[0030] The reference numerals are as follows:
[0031] protective cover 1 and monitoring head 2;
[0032] connecting pipe 11, card slot 12, push plate 13, push rod 14, cover body 15, filter membrane 16, sealing ring 17 and threaded sleeve 18;
[0033] docking pipe 21, claw 22, elastic ring 23, expansion plate 24, fixing plate 25 and outer housing 26;
[0034] limiting tooth 221;
[0035] top push groove 241;
[0036] avoidance groove 251;
[0037] limiting ring 261. Detailed implementation manners
[0038] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.
[0039] In order to enable those skilled in the art in this technical field to better understand the solution of the present invention, the present invention will be further described in detail below in conjunction with the drawings and specific embodiments.
[0040] The embodiment of the present invention discloses a protection monitoring connection structure of a pressure sensor. As shown in the attached Figure 1 figure, it includes a protective cover 1 and a monitoring head 2. The protective cover 1 is used to separate the external circulation pipeline and the pressure sensor to ensure that the pressure sensor remains dry. The monitoring head 2 is used to connect the pressure sensor of the device.
[0041] As shown in the attached Figures 1 to 4As shown, a connecting pipe 11 is fixedly provided at one end of the protective cover 1, and a slot 12 is provided on the outer side of the connecting pipe 11, and the slot 12 can be an annular slot. A butt joint pipe 21 is fixedly provided at one end of the monitoring head 2, and at least one hook 22 is hingedly connected to the outer side of the butt joint pipe 21. A hook portion and a connecting portion are respectively provided at both ends of each hook 22, and the hook portion extends along the radial direction of the butt joint pipe 21 and matches with the slot 12 along the radial direction of the butt joint pipe 21; the connecting portion is an arc structure extending along the radial direction of the butt joint pipe 21, and the connecting portion is hingedly connected to the fixing plate 25.
[0042] When the connecting pipe 11 is butt-joined with the butt-joint pipe 21, the two hollow pipes of the connecting pipe 11 and the butt-joint pipe 21 are coaxially connected, and all the hook claws 22 are retracted along the radial direction of the butt-joint pipe 21 under the action of external force. Figure 6 As shown, until all the hook claws 22 are inserted into the slots 12, the connecting pipe 11 and the butt pipe 21 are restricted from relative movement in the axial direction, so that the protective cover 1 and the monitoring head 2 are fixedly connected. Figure 1 shown.
[0043] The utility model optimizes the connection mode between the protective cover 1 and the monitoring head 2, changing the original threaded connection to a grip connection, avoiding the loosening of the threaded connection, and preventing the liquid from accidentally overflowing to the outside of the extracorporeal circulation pipeline through the protective cover 1, which is safer; moreover, the utility model can replace the complex screwing operation with a simple push-pull operation, which is more convenient to operate and increases the convenience of operation. Therefore, the safety and convenience of operation of the protective monitoring connection structure in the utility model are both high.
[0044] The butt joint tube 21 is slidably sleeved with an expansion plate 24, and all the hook claws 22 are radially against the expansion plate 24. By adjusting the position of the expansion plate 24 on the butt joint tube 21, the opening range of all the hook claws 22 is adjusted. When the expansion plate 24 is away from the protective cover 1, all the hook claws 22 are opened; when the expansion plate 24 is close to the protective cover 1, all the hook claws 22 are closed.
[0045] When the push plate 13 is pushed along the axial direction of the connecting tube 11, the push plate 13 drives all the push rods 14 to enter the monitoring head 2. When all the push rods 14 push the expansion plate 24 to move along the butt joint tube 21 in a direction away from the protective cover 1, the expansion plate 24 pushes all the hook claws 22 to overcome the elastic force of the elastic ring 23 and expand along the radial direction of the butt joint tube 21. Figure 10 As shown in FIG. 1 , until all the hook claws 22 are out of the slots 12, the protective cover 1 only needs to be pulled out to separate the connecting pipe 11 and the butt pipe 21, so that the protective cover 1 and the monitoring head 2 can be disassembled. Figure 9 As shown, disassembly is more convenient, which increases the convenience of operation.
[0046] As attached Figure 5 and 6As shown, the monitoring head 2 includes an elastically deformable ring 23 fixedly arranged, and all the hook claws 22 pass through the elastically deformable ring 23. When all the hook claws 22 expand radially, all the hook claws 22 radially extrude the elastically deformable ring 23 along the docking pipe 21; when the push rod 14 is separated from the expansion plate 24, the elastically deformable ring 23 restores its elastic deformation, and the elastically deformable ring 23 relies on the elastic force to push all the hook claws 22 to automatically close along the radial direction of the docking pipe 21.
[0047] The monitoring head 2 further includes an outer housing 26 covering the outside of all the hook claws 22. The outer housing 26 is a hollow structure, with a conical outer side and a cylindrical inner side. The inner side wall of the outer housing 26 is provided with an annular fixing groove, and the elastically deformable ring 23 is fixedly arranged in the annular fixing groove. The elastically deformable ring 23 is circular, and has a tendency to close towards the center along the radial direction, providing a radial force for all the hook claws 22, causing all the hook claws 22 to close along the radial direction, and providing a pre-tightening force for all the hook claws 22 to clamp the connecting pipe 11, ensuring a reliable connection between the connecting pipe 11 and the docking pipe 21.
[0048] As shown in the appendix Figure 5 and 6 As shown, a push plate 13 is slidably sleeved on one end of the connecting pipe 11, enabling the push plate 13 to move along the outer side surface of the connecting pipe 11. At least one push rod 14 is perpendicularly fixedly arranged on the side of the push plate 13 facing the monitoring head 2. Each push rod 14 extends along the axial direction of the connecting pipe 11, and all the push rods 14 are evenly distributed along the circumferential direction of the connecting pipe 11. The push rod 14 is used to push the expansion plate 24 to slide along the docking pipe 21 to adjust the opening and closing state of all the hook claws 22. It should be particularly noted that to avoid interference between the connecting pipe 11 and the expansion plate 24, in the axial direction of the connecting pipe 11, the lengths of all the push rods 14 are equal and are all greater than the length of the connecting pipe 11, that is, the end of each push rod 14 extends beyond the end of the connecting pipe 11.
[0049] As shown in the appendix Figure 7 and 8 As shown, the monitoring head 2 includes a fixing plate 25, and all the hook claws 22 are hinged to the fixing plate 25 through a hinge shaft, enabling all the hook claws 22 to gather or expand. A return torsion spring is sleeved on the hinge shaft, and the two torsion arms of the return torsion spring respectively abut against the hook claws 22 and the fixing plate 25. When the protective cover 1 is separated from the monitoring head 2, the return torsion spring provides a return elastic force for the hook claws 22 to ensure the quick reset of the hook claws 22. All the hook claws 22 are evenly distributed along the circumferential direction of the docking pipe 21. When the protective cover 1 is connected to the monitoring head 2, all the push rods 14 and all the hook claws 22 are staggeredly distributed along the circumferential direction of the docking pipe 21 to avoid interference. In addition, considering that the end of the hook claw 22 connected to the fixing plate 25 is an arc structure, the fixing plate 25 is provided with a number of avoidance grooves 251. The avoidance grooves 251 are arc grooves extending along the thickness direction of the fixing plate 25 to prevent the fixing plate 25 from hindering the full expansion of all the hook claws 22.
[0050] As shown in the appendix Figure 7As shown, at least one pushing groove 241 is fixedly provided on the expansion plate 24. The pushing groove 241 extends along the radial direction of the expansion plate 24. The pushing groove 241 is matched with the hook claw 22 along the radial direction of the docking pipe 21. The pushing groove 241 can not only provide a pushing force for the hook claw 22 along the radial direction of the docking pipe 21, but also limit the circumferential movement of the hook claw 22 along the docking pipe 21, avoiding the situation that the hook claw 22 fails to firmly hold the connecting pipe 11.
[0051] A limiting tooth 221 is provided in the middle section of the hook claw 22. The limiting tooth 221 is arranged on the side of the hook claw 22 facing the docking pipe 21 and extends along the radial direction of the docking pipe 21. When the hook claw 22 is clamped into the clamping groove 12, the limiting tooth 221 abuts against the groove edge of the pushing groove 241. As shown in Figure 1 、 5 and 6, that is, the limiting tooth 221 abuts against the expansion plate 24 in the axial direction of the docking pipe 21, restricting the axial movement of the expansion plate 24 along the docking pipe 21 towards the protective cover 1. This avoids the situation that the clamping force applied by all the hook claws 22 to the connecting pipe 11 is too large due to excessive movement of the expansion plate 24 along the docking pipe 21, and also avoids the expansion plate 24 interfering with the situation that all the hook claws 22 fail to firmly hold the connecting pipe 11.
[0052] As shown in Figure 5 and 6 , the fixing plate 25 is coaxially and fixedly arranged between the docking pipe 21 and the outer housing 26, ensuring that the center lines of all the hook claws 22 coincide with the center line of the docking pipe 21, avoiding the situation that the hook claws 22 fail to firmly hold the connecting pipe 11 due to misalignment. The fixing plate 25 is also used to support the docking pipe 21 and the outer housing 26, enabling all the hook claws 22 to act relative to the docking pipe 21. The fixing plate 25 is specifically in a disc shape, but is not limited thereto.
[0053] As shown in Figure 5 and 6 , one end of the outer housing 26 is provided with an open mouth for the connecting pipe 11 to be inserted. An integral limiting ring 261 is formed along the inner side of the open mouth. The limiting ring 261 is used to restrict the elastic ring 23 from separating from all the hook claws 22, avoiding the elastic ring 23 separating from the hook claws 22.
[0054] As shown in Figure 3 , the protective cover 1 includes a cover body 15 coaxially connected to the connecting pipe 11. A filter membrane 16 is provided inside the cover body 15. The filter membrane 16 is breathable and waterproof, which can separate the external circulation pipeline and the pressure sensor, so that the pressure sensor remains dry. The diameter of the push plate 13 is larger than the diameter of the cover body 15, making the push plate 13 protrude from the cover body 15, facilitating the hand-held push plate 13. The diameter of the push plate 13 is larger than the diameter of the outer housing 26, which is also convenient for hand-held.
[0055] As shown in Figure 3 and 4As shown, a threaded sleeve 18 is fixedly arranged at one end of the protective cover 1 away from the connecting pipe 11, and the threaded sleeve 18 is used to connect the external circulation pipeline. The threaded sleeve 18, the cover body 15 and the connecting pipe 11 are coaxially connected. A tapered tube is fixedly arranged at the center of the threaded sleeve 18, and the tapered tube is coaxial with the threaded sleeve 18.
[0056] As attached Figure 1 and 9 As shown, the inner wall of the connecting pipe 11 is provided with a sealing ring 17. When the connecting pipe 11 is connected to the butt joint pipe 21, the sealing ring 17 abuts between the connecting pipe 11 and the butt joint pipe 21 to ensure good air tightness between the protective cover 1 and the monitoring head 2. The sealing ring 17 can be an O-type rubber ring, but is not limited thereto. The inner wall of the connecting pipe 11 is provided with an annular groove, and the sealing ring 17 is fixed in the annular groove, and the sealing ring 17 protrudes from the annular groove.
[0057] Considering that the connecting pipe 11 is a hollow circular pipe, the end of the butt joint pipe 21 facing the connecting pipe 11 is a conical structure, as shown in the attached Figure 5 and 6 As shown, it is convenient to quickly insert the butt joint pipe 21 into the connecting pipe 11, and also provides a moving space for the axial relative movement of the connecting pipe 11 and the butt joint pipe 21 when pushing the push plate 13. Of course, the structures of the connecting pipe 11 and the butt joint pipe 21 are not limited to this, for example, the structures of the two can be interchanged without affecting the purpose of the present invention.
[0058] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.
[0059] This article uses specific examples to illustrate the principles and implementation methods of the utility model. The above examples are only used to help understand the method and core ideas of the utility model. It should be pointed out that for ordinary technicians in this technical field, at least one improvement and modification can be made to the utility model without departing from the principle of the utility model, and these improvements and modifications also fall within the scope of protection of the claims of the utility model.
Claims
1. A protection monitoring connection structure of a pressure sensor, characterized in that: The invention comprises a protective cover (1) and a monitoring head (2); a connecting pipe (11) is fixedly provided at one end of the protective cover (1), and a clamping groove (12) is provided on the outer side surface of the connecting pipe (11); a butt joint pipe (21) is fixedly provided at one end of the monitoring head (2), and at least one hook (22) is hingedly connected on the outer side surface of the butt joint pipe (21); when the connecting pipe (11) is butt-jointed with the butt joint pipe (21), all the hooks (22) are retracted along the radial direction of the butt joint pipe (21) until they are clamped into the clamping groove (12).
2. The protection monitoring connection structure of the pressure sensor according to claim 1, characterized in that: One end of the connecting tube (11) is slidably provided with a push plate (13), and the push plate (13) is fixed with at least one push rod (14) extending along the axial direction of the connecting tube (11); the butt joint tube (21) is slidably provided with an expansion plate (24), and all the hook claws (22) are radially abutted against the expansion plate (24); when all the push rods (14) are driven by the push plate (13) to push the expansion plate (24) to move away from the protective cover (1), the expansion plate (24) is used to push all the hook claws (22) to expand along the radial direction of the butt joint tube (21) until they are out of the slot (12).
3. The protection monitoring connection structure of the pressure sensor according to claim 2, characterized in that: The monitoring head (2) comprises a fixed elastic ring (23), through which all the hook claws (22) pass; when all the hook claws (22) expand radially, all the hook claws (22) squeeze the elastic ring (23) along the radial direction of the butt joint (21); when the push rod (14) is separated from the expansion plate (24), the elastic ring (23) is used to push all the hook claws (22) to retract radially by restoring elastic deformation.
4. The protection monitoring connection structure of the pressure sensor according to claim 3, characterized in that: The monitoring head (2) further comprises an outer cover shell (26) which is arranged outside all the hook claws (22); an inner side wall of the outer cover shell (26) is provided with an annular fixing groove, and the elastic ring (23) is fixedly arranged in the annular fixing groove.
5. The protection monitoring connection structure of the pressure sensor according to claim 3, characterized in that: The monitoring head (2) also includes a fixing plate (25), and all the hook claws (22) are hingedly connected to the fixing plate (25) via a hinge shaft; the hinge shaft sleeve is provided with a reset torsion spring respectively abutting against the hook claws (22) and the fixing plate (25).
6. The protection monitoring connection structure of the pressure sensor according to claim 3, characterized in that: The expansion plate (24) is fixedly provided with at least one pushing groove (241) matched with the hook claw (22), and the hook claw (22) is provided with a limiting tooth (221); when the hook claw (22) is inserted into the slot (12), the limiting tooth (221) is used to abut against the groove edge of the pushing groove (241) to limit the expansion plate (24) from excessively moving toward the protective cover (1).
7. The protection monitoring connection structure of the pressure sensor according to claim 4, characterized in that: One end of the outer cover shell (26) is provided with an opening for inserting the connecting pipe (11), and a limiting ring (261) is integrally formed along the inner side of the opening, and the limiting ring (261) is used to limit the elastic ring (23) from detaching from all the hook claws (22).
8. The protection monitoring connection structure of the pressure sensor according to claim 2, characterized in that: The protective cover (1) comprises a cover body (15) coaxially connected to the connecting pipe (11), wherein a filter membrane (16) is arranged inside the cover body (15); and the diameter of the push plate (13) is larger than the diameter of the cover body (15).
9. The protection monitoring connection structure of the pressure sensor according to any one of claims 1 to 8, characterized in that: The inner side wall of the connecting pipe (11) is provided with a sealing ring (17); when the connecting pipe (11) and the butt joint pipe (21) are butt-jointed, the sealing ring (17) abuts between the connecting pipe (11) and the butt joint pipe (21).
10. The protection monitoring connection structure of the pressure sensor according to any one of claims 1 to 8, characterized in that: One end of the butt joint pipe (21) facing the connecting pipe (11) is a conical structure.