CN212016425U

CN212016425U - Balloon catheter

Info

Publication number: CN212016425U
Application number: CN201922266928.5U
Authority: CN
Inventors: 吴星宇; 龙汉; 张�雄; 刘全祖
Original assignee: Lifetech Scientific Shenzhen Co Ltd
Current assignee: Shenzhen Jianxin Medical Technology Co ltd
Priority date: 2019-12-17
Filing date: 2019-12-17
Publication date: 2020-11-27
Anticipated expiration: 2029-12-17

Abstract

The utility model relates to a balloon catheter, which comprises a catheter main body and a catheter seat, wherein a charging and discharging cavity and a thread guide cavity are arranged in the catheter main body, a filling cavity communicated with an inner cavity of the catheter seat is arranged on the side wall of the catheter seat, and the filling cavity is communicated with the charging and discharging cavity through the inner cavity; a first rubber cavity and a second rubber cavity are formed between the outer wall of the catheter main body and the inner wall of the catheter seat, a first resisting part is arranged on the proximal side of the first rubber cavity, a second resisting part is arranged on the distal side of the second rubber cavity, and the position where the filling cavity is communicated with the inner cavity is located between the first resisting part and the second resisting part. The utility model discloses a sacculus pipe, the first near-end side of gluing the chamber has first department of keeping out, and the distal end side in chamber is glued to the second has second department of keeping out to avoid the first glue chamber and the glue jam in second gluey chamber to fill and unload the passageway of chamber to distal end conveying gas or liquid, in order to maintain the good result of use of sacculus pipe, simultaneously, first glue chamber and second glue the glue solidification back in the chamber can the joint strength between pipe seat and the pipe main part.

Description

Balloon catheter

Technical Field

The utility model relates to an intervene medical instrument technical field, especially relate to a sacculus pipe.

Background

The balloon catheter is an important medical device in interventional therapy, and the typical structure of the balloon catheter comprises an expandable balloon with the distal end serving as a working section, a catheter seat positioned outside the body, and a catheter main body which is connected with the expandable balloon and the catheter seat and plays the roles of pushing, withdrawing and inflating and deflating. The three parts form a closed cavity. The filling cavity on the catheter seat is used as a butt joint, and the inflation and the deflation of the expandable balloon section are controlled in vitro, so that the interventional treatment on the narrow blood vessel and the endovascular prosthesis is realized.

Therefore, the connection stability between the components is very important, certain connection strength needs to be met, and no leakage exists. In the process of preparing the balloon catheter, the catheter base and the catheter main body are connected by directly connecting glue, but the connection mode cannot ensure that the catheter base and the catheter main body are stably matched after the glue is cured, and the leakage risk still exists. Although the bonding force between the catheter main body and the catheter base can be enhanced by increasing the glue dispensing amount, the risk that the communicated position of the filling cavity and the filling and discharging cavity is blocked by glue exists, and the fluid injected from the filling cavity is influenced to be conveyed into the balloon through the filling and discharging cavity.

SUMMERY OF THE UTILITY MODEL

Based on this, it is necessary to provide a balloon catheter, which can improve the connection strength between the catheter holder and the catheter main body, and the glue is not easy to block the communication position between the filling and discharging cavity and the filling cavity.

A balloon catheter comprising:

the catheter comprises a catheter main body, a catheter core and a catheter core, wherein a charging and discharging cavity and a guide wire cavity are arranged in the catheter main body, and the charging and discharging cavity and the guide wire cavity extend along the axial direction of the catheter main body and are not communicated with each other; and

the catheter base is provided with an inner cavity extending axially, the near end of the catheter main body is accommodated in the inner cavity of the catheter base, a filling cavity communicated with the inner cavity is arranged on the side wall of the catheter base, and the filling cavity is communicated with the charging and discharging cavity through the inner cavity;

the catheter comprises a catheter base, a catheter main body and a filling cavity, wherein a first rubber cavity and a second rubber cavity are formed by enclosing the outer wall of the catheter main body and the inner wall of the catheter base, a first resisting part is arranged on the proximal end side of the first rubber cavity, a second resisting part is arranged on the distal end side of the second rubber cavity, and the position where the filling cavity is communicated with the inner cavity is located between the first resisting part and the second resisting part; and a first glue dispensing opening communicated with the first glue cavity and a second glue dispensing opening communicated with the second glue cavity are formed in the catheter base.

In one embodiment, the first abutting portion and the second abutting portion are coaxially arranged.

In one embodiment, the wall of the catheter base is further provided with a first exhaust port communicated with the first rubber cavity and a second exhaust port communicated with the second rubber cavity; the first air outlet is used for exhausting air in the first glue cavity when fluid is injected through the first glue dispensing opening; and when fluid is injected through the second dispensing port, the second exhaust port is used for exhausting gas in the second dispensing cavity.

In one embodiment, the catheter body comprises an inner tube and an outer tube, wherein the inner tube and the outer tube are hollow, the outer tube is sleeved outside the inner tube, the inner diameter of the outer tube is larger than the outer diameter of the inner tube, and the proximal end of the inner tube extends out of the proximal end of the outer tube; the first resisting part and the second resisting part are both annular pieces, the first resisting part is sleeved on the near end of the outer tube and is abutted against the inner wall of the catheter seat, and the second resisting part is sleeved on the near end of the inner tube and is abutted against the inner wall of the catheter seat.

In one embodiment, a first insertion hole and a second insertion hole which are coaxially connected are arranged in the inner cavity of the catheter holder, the inner diameter of the first insertion hole is larger than that of the second insertion hole, the first insertion hole is used for accommodating the proximal end of the outer tube and the first abutting portion, and the second insertion hole is used for accommodating the proximal end of the inner tube and the second abutting portion.

In one embodiment, the catheter body has at least 2 lumens inside the catheter body, the at least 2 lumens all extend along the axial direction of the catheter body, at least 1 lumen forms the inflation/deflation lumen, and the catheter body is provided with an inflation/deflation hole penetrating through the inflation/deflation lumen, and the inflation/deflation hole is used for communicating the inflation/deflation lumen with the inflation lumen of the catheter hub.

In one embodiment, the inner wall of the catheter hub has a first boss and a second boss abutting against the outer wall of the catheter body, the first boss and the second boss are arranged at intervals at a proximal end side and a distal end side of a position where the inflation and deflation cavity is communicated with the inflation cavity, the catheter body is spaced from the inner wall of the catheter hub under the support of the first boss and the second boss to form a first glue cavity and a second glue cavity, the first glue cavity is located at the distal end side of the first boss, and the second glue cavity is located at the proximal end side of the second boss.

In one embodiment, the wall of the catheter main body is provided with a hole or a groove for communicating the filling and discharging cavity with the second glue cavity, so that when glue is injected into the second glue cavity, the glue flows into the proximal side of the filling and discharging cavity from the hole or the groove and blocks the proximal side of the filling and discharging cavity;

or a sealing piece is arranged at the proximal end side of the charging and discharging cavity of the catheter main body and used for sealing off the proximal end side of the charging and discharging cavity.

In one embodiment, the outer wall of the catheter main body abuts against the inner wall of the catheter seat to form the first abutting portion and the second abutting portion, the plurality of filling and discharging cavities of the catheter main body are arranged around the peripheral side of the guide wire cavity, at least one annular groove is formed in the proximal end of the catheter main body, the groove bottom of the annular groove is formed by walls which are formed by surrounding the guide wire cavity, the annular groove is communicated with the filling cavity of the catheter seat and is provided with a plurality of openings, and the filling cavity is communicated with the plurality of filling and discharging cavities through the plurality of openings.

In one embodiment, the far end of the catheter seat is provided with a step groove, and the first glue cavity is formed between the wall which encloses the step groove and the outer wall of the catheter main body; the proximal end of the catheter main body is provided with an annular notch, the bottom of the annular notch is formed by a wall which encloses to form the guide wire cavity, and when the catheter main body is abutted against the inner wall of the catheter seat, the annular notch forms the second rubber cavity; a first sealing band is arranged on the proximal side of the annular groove, or a second sealing band is arranged on the distal side of the annular recess.

The utility model provides a sacculus pipe, including pipe main part and pipe seat, be formed with first gluey chamber and the gluey chamber of second between the surface of pipe main part and the inner wall of pipe seat, the first near-end side of gluing the chamber has first department of keeping out, the distal end side that the chamber was glued to the second has second department of keeping out, thereby avoid the first glue chamber and the gluey glue jam in chamber of second to fill and unload the passageway that the chamber was carried gas or liquid to the distal end, in order to maintain the good result of use of sacculus pipe, simultaneously, first glue chamber and second glue the glue in the chamber can the joint strength between pipe seat and the pipe main part after the solidification.

Drawings

Fig. 1 is a schematic view of an overall structure of a balloon catheter according to an embodiment of the present invention;

FIG. 2 is a schematic view of the assembled structure of the catheter body and the catheter hub in the balloon catheter structure shown in FIG. 1;

FIG. 3 is a schematic cross-sectional view of the catheter body shown in FIG. 2, showing an outer jacket of the catheter body disposed outside of the inner tube;

FIG. 4 is a schematic view of another embodiment of a catheter body and catheter hub assembly;

FIG. 5 is a schematic view of an assembly structure of a catheter body and a catheter hub according to yet another embodiment;

FIG. 6 is a schematic view illustrating an assembled structure of a catheter main body and a catheter hub when the catheter main body is a multi-lumen tube according to an embodiment;

FIG. 7 is a schematic cross-sectional view of a catheter body in one embodiment showing the catheter body having multiple lumens;

FIG. 8 is a schematic view of another embodiment of a catheter body and catheter hub assembly;

FIG. 9 is a schematic view of an assembly structure of a catheter main body and a catheter hub according to still another embodiment when the catheter main body is a multi-lumen catheter;

FIG. 10 is a cross-sectional view of an embodiment of the catheter body of FIG. 9 showing the assembled configuration of the catheter body and catheter hub;

fig. 11 is a perspective view of the catheter main body in the assembled structure of the catheter main body and the catheter hub shown in fig. 9.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. The preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the field of interventional medical devices, the end of a medical device implanted in a human or animal body closer to an operator is generally referred to as the "proximal end", the end farther from the operator is referred to as the "distal end", and the "proximal end" and the "distal end" of any component of the medical device are defined according to this principle. "axial" generally refers to the length of the medical device as it is being delivered, and "radial" generally refers to the direction of the medical device perpendicular to its "axial" direction, and defines both "axial" and "radial" directions for any component of the medical device in accordance with this principle.

Referring to fig. 1, a balloon catheter 100 according to an embodiment of the present disclosure includes an expandable balloon 10, a catheter main body 20, and a catheter hub 30.

The expandable balloon 10 is disposed at the distal end of the catheter body 20, and the proximal end of the catheter body 20 is received in the inner lumen 30b of the catheter hub 30 and connected to the catheter hub 30. The catheter main body 20 is formed with an inflation/deflation chamber 20a and a guide wire chamber 20b, and the interior of the inflatable balloon 10 is communicated with the inner chamber 30b of the catheter hub 30 through the inflation/deflation chamber 20 a. The guide wire lumen 20b is used to accommodate the guide wire 101, and more specifically, the guide wire 101 can pass axially through the guide wire lumen 20 b. The guidewire 101 passes from the proximal end of the catheter hub 30 into a guidewire lumen 20b in the catheter body 20 and out the distal end of the catheter body 20.

A branch tube is provided on the side wall of the catheter hub 30, the branch tube defining a filling lumen 30a, the filling lumen 30a communicating with the lumen 30b of the catheter hub 30 and being at an acute angle to the axial direction of the lumen 30b of the catheter hub 30. In other embodiments, a portion of the filling lumen 30a near its distal tip communicates with the lumen 30b of the catheter hub 30, and the other portion of the filling lumen 30a is substantially parallel to the lumen 30b of the catheter hub 30. The filling lumen 30a may communicate with the inflation and deflation lumen 20a through the lumen 30b of the catheter hub 30 and with an external device (not shown) for injecting gas or liquid into the filling lumen 30a, such that when the external device releases the filling gas or liquid at a certain pressure, the filling gas or liquid will enter the lumen 30b of the catheter hub 30 from the filling lumen 30a and enter the inflation and deflation lumen 20a from the lumen 30b of the catheter hub 30, thereby reaching the interior of the inflatable balloon 10 from the inflation and deflation lumen 20a to fill the inflatable balloon 10, so that the inflatable balloon 10 is inflated.

The proximal end of the catheter body 20 is coaxially disposed within the lumen 30b of the catheter hub 30. Catheter hub 30 is made of a polymeric material, such as a Polycarbonate (PC) material.

Catheter hub 30 has a first dispensing port 301 and a second dispensing port 302, the first dispensing port 301 being located on the distal side of catheter hub 30 and the second dispensing port 302 being located on the proximal side of catheter hub 30. After the proximal end of the catheter main body 20 is arranged in the inner cavity 30b of the catheter hub 30, a first glue cavity 303 and a second glue cavity 304 are formed between the outer wall of the proximal end of the catheter main body 20 and the inner wall of the catheter hub 30, wherein the first glue dispensing opening 301 penetrates through the wall of the catheter hub 30 and is communicated with the first glue cavity 303, and the second glue dispensing opening 302 penetrates through the wall of the catheter hub 30 and is communicated with the second glue cavity 304. Glue can be injected into the first glue cavity 303 and the second glue cavity 304 through the first glue dispensing opening 301 and the second glue dispensing opening 302 respectively, so that the connection stability between the catheter main body 20 and the catheter hub 30 can be enhanced by the glue.

It should be noted that in some embodiments, the first glue-applying opening may be formed by a gap between the inner wall of the catheter hub 30 near the distal end and the outer wall of the catheter main body 20, and specifically, glue may be injected into the first glue cavity 303 from a gap between the outer wall of the catheter main body 20 and the inner wall of the catheter hub 30 near the distal end. Accordingly, the second dispensing opening may be formed by a gap between an inner wall of the catheter hub 30 near the proximal end and an outer wall of the catheter body 20. For the structure of the first dispensing opening and the second dispensing opening, no further description is given here, as long as the first dispensing opening and the second dispensing opening can meet the requirement of injecting glue into the corresponding first glue cavity 302 and the second glue cavity 304.

In other embodiments, referring to fig. 2, the catheter hub 30 is provided with a first exhaust port 305 and a second exhaust port 306 penetrating through the wall thereof, the first exhaust port 305 is communicated with the first glue cavity 303, so that when glue is injected from the first glue applying port 301 to the first glue cavity 303, the first exhaust port 305 can achieve a better exhaust effect, so that the glue can be injected into the first glue cavity 303 more smoothly, and bubbles are not easily formed, so as to enhance the bonding effect of the glue between the catheter body 20 and the catheter hub 30. Correspondingly, the second air vent 306 is communicated with the second glue cavity 304, so that when glue is injected into the second glue cavity 304 from the second glue dispensing opening 302, the glue can be injected into the second glue cavity 304 more smoothly by the arrangement of the second air vent 306, and no air bubble is formed.

The proximal side of the first glue cavity 303 is provided with a first stopping part 110, the first stopping part 110 is used for stopping the glue injected into the first glue cavity 303 from flowing to the proximal end of the filling and discharging cavity 20a before being solidified, and the filling and discharging cavity 20a is blocked after being solidified. Correspondingly, the distal end side of the second glue cavity 304 is provided with the second stopping part 120, and the glue injected into the second glue cavity 304 is stopped by the second stopping part 120 from flowing along the inner cavity 30b of the catheter hub 30 to the proximal end of the charging and discharging cavity 20a before being cured, and then blocks the charging and discharging cavity 20a after being cured. With this arrangement, the risk of glue running to the proximal end of the inflation and deflation lumen 20a, and even into the inflation and deflation lumen 20a, and clogging the inflation and deflation lumen 20a after curing is effectively reduced, thereby ensuring the reliability of the inflation and deflation lumen 20a for the inflatable balloon 10 to be inflated with gas or liquid.

It should be noted that the first resisting portion 110 and the second resisting portion 120 may be formed by separate structural members disposed between the catheter main body 20 and the catheter hub 30. In other embodiments, first and

second abutments

110 and 120 are formed by modifying the structure of the inner wall of catheter hub 30 or the structure of catheter body 20 such that catheter body 20 mates with the inner wall of catheter hub 30.

The structure of the balloon catheter 100 will be further described below in conjunction with the structure of the catheter body 20 and catheter hub 30.

Example 1

As shown in fig. 2 and 3 in combination, in the balloon catheter 100 of example 1, the catheter main body 20 includes an outer tube 21 and an inner tube 22, and the outer tube 21 has an inner diameter larger than an outer diameter of the inner tube 22. The outer tube 21 is sleeved outside the inner tube 22, the proximal end of the inner tube 22 extends out of the proximal end of the outer tube 21, a gap between the outer wall of the inner tube 22 and the inner wall of the outer tube 21 forms a charging and discharging cavity 20a, and the lumen of the inner tube 22 is a guide wire cavity 20 b.

The proximal end of outer tube 21 is connected to the inner wall of catheter hub 30 by first abutment 110, and the proximal end of inner tube 22 is connected to the inner wall of catheter hub 30 by second abutment 120.

The first abutting portion 110 and the second abutting portion 120 are both annular members and are coaxially disposed. The first resisting portion 110 is sleeved on the proximal end of the outer tube 21 and is contacted with the inner wall of the catheter hub 30, and the second resisting portion 120 is sleeved on the proximal end of the inner tube 22 and is contacted with the inner wall of the catheter hub 30. Since the first abutting portion 110 and the second abutting portion 120 are coaxially disposed, the proximal end of the outer tube 21 and the proximal end of the inner tube 22 will be coaxially fixed in the inner cavity 30b of the catheter hub 30.

Inner tube 22 and outer tube 21 may each be connected to catheter hub 30 by adhesive, thermoplastic, interference fit, or the like.

Referring to fig. 2, a first insertion hole 301b and a second insertion hole 302b coaxially connected are disposed in the inner cavity 30b of the catheter hub 30, an inner diameter of the first insertion hole 301b is larger than an inner diameter of the second insertion hole 302b, a proximal end of the outer tube 21 is matched with the first insertion hole 301b through the first abutting portion 110, and at this time, the proximal end of the outer tube 21 and the first abutting portion 110 are accommodated in the first insertion hole 301 b. The proximal end of the inner tube 22 extends from the proximal end of the outer tube 21 and is engaged with the second insertion hole 302b through the second abutting portion 120, and the proximal end of the inner tube 22 is received in the second insertion hole 302b together with the second abutting portion 120.

In some embodiments, as shown in fig. 2, since the diameter of the first insertion hole 301b is larger than that of the second insertion hole 302b, the joint of the two is stepped, so that when the inner tube 22 is fitted into the second insertion hole 302b, a gap is formed between a part of the outer wall of the inner tube 22 and the inner wall of the catheter hub 30 surrounding the first insertion hole 301b, so as to communicate the filling cavity 30a with the filling and discharging cavity 20a through the gap.

Referring to fig. 2, the first resisting portion 110 includes an outer tube collar 21a, and the outer tube collar 21a is sleeved on the proximal end of the outer tube 21. On the distal end side of the outer tube collar 21a, a first glue chamber 303 is formed between the inner wall of the catheter hub 30 enclosing the first insertion hole 301b and the outer wall of the outer tube 21. The first glue applying opening 301 of the catheter hub 30 is communicated with the first glue cavity 303, so that glue can be injected into the first glue cavity 303 through the first glue applying opening 301. The glue can enhance the stability of the connection between the outer tube 21 and the catheter hub 30 after curing.

Since the first glue cavity 303 is located at the distal end side of the outer tube sleeve ring 21a, the outer tube sleeve ring 21a can block the glue in the first glue cavity 303 from flowing out towards the proximal end, and prevent the uncured glue in the first glue cavity 303 from flowing to the proximal end of the filling and discharging cavity 20a, so as to prevent the filling and discharging cavity 20a from being blocked by the glue.

In other embodiments, the side wall enclosing the first insertion hole 301b is cylindrical, and the outer tube collar 21a is a circular ring with a uniform wall thickness, so that when the outer tube 21 is fitted to the outer tube collar 21a, the portion of the outer tube 21 located in the first insertion hole 301b is coaxial with the first insertion hole 301b, and then the first rubber cavity 303 is a circular space. Therefore, after glue is injected into the first glue cavity 303, the glue can be filled more evenly between the outer wall of the outer tube 21 and the inner wall of the catheter hub 30, which is beneficial to improving the stability of connection between the outer tube 21 and the catheter hub 30.

With continued reference to fig. 2, the second stop 120 includes a first inner tube collar 22a, the inner tube collar 22a fitting over the proximal exterior of the inner tube 22. On the proximal side of the inner tube collar 22a, a second glue lumen 304 is formed between the inner wall of the catheter hub 30 enclosing the second receptacle 302b and the outer wall of the inner tube 22. A second glue dispensing opening 302 is formed in the wall of the catheter hub 30, and the second glue dispensing opening 302 is communicated with a second glue cavity 304, so that glue can be injected into the second glue cavity 304 through the second glue dispensing opening 302. The glue, when cured, enhances the stability of the connection between the inner tube 22 and the catheter hub 30.

Since the second glue cavity 304 is located at the proximal side of the inner tube collar 22a, the inner tube collar 22a functions to block the glue in the second glue cavity 304 from flowing out towards the distal end, and prevent the uncured glue in the second glue cavity 304 from flowing to the proximal end of the filling and discharging cavity 20a, so as to prevent the filling and discharging cavity 20a from being blocked by the glue.

In some embodiments, the inner wall of the catheter hub 30 that surrounds the second insertion hole 302b is annular, and the inner tube collar 22a is annular with a uniform wall thickness, so that when the inner tube 22 is fitted to the inner tube collar 22a, the portion of the inner tube 22 located in the second insertion hole 302b is coaxial with the second insertion hole 302b, and then the second rubber cavity 304 is an annular space. Therefore, after glue is injected into the second glue cavity 304, the glue can be more evenly filled between the outer wall of the inner tube 22 and the inner wall of the catheter seat 30 which encloses to form the second insertion hole 302b, and thus, the stability of connection between the inner tube 22 and the catheter seat 30 is improved.

In the embodiment shown in fig. 3, in which the inner tube collar 22a and the outer tube collar 21a are coaxially disposed, the inner tube 22 and the outer tube 21 can be coaxially disposed in the inner cavity 30b of the catheter hub 30 under the action of the inner tube collar 22a and the outer tube collar 21 a. It should be noted that the glue injected into the first glue cavity 303 and the second glue cavity 304 may be a UV curable glue, or may be other curable fluid glues.

The inner diameter of the portion of the catheter hub 30 corresponding to the outer tube 21 may also be equal to the inner diameter of the portion of the catheter hub 30 corresponding to the inner tube 22, and at this time, only the wall thicknesses of the annular first abutting portion 110 and the annular second abutting portion 120 need to be adjusted correspondingly, specifically, the wall thickness of the second abutting portion 120 is greater than that of the first abutting portion 110. With this arrangement, the proximal ends of the outer tube 21 and the inner tube 22 can be coaxially disposed in the lumen 30b of the catheter hub 30 via the first abutting portion 110 and the second abutting portion 120, respectively.

In some embodiments, outer tube collar 21a within first receptacle 301b is a unitary structure with catheter hub 30, e.g., outer tube collar 21a is disposed within first receptacle 301b of catheter hub 30 by injection molding. The material of the outer tube sleeve 21a may be the same as or different from that of the catheter hub 30.

It should be noted that, for the case where the outer tube collar 21a is injection-molded integrally with the catheter hub 30, the outer tube collar 21a is considered to be a part of the catheter hub 30, and need not be separately provided. For example, as shown in connection with FIG. 4, outer tube collar 21a is formed as part of catheter hub 30 within first receptacle 301b to form a boss structure. This arrangement also effectively prevents the uncured glue in the first glue chamber 303 from flowing to the proximal end of the fill and discharge chamber 20 a.

Accordingly, inner tube collar 22a in second receptacle 302b may also be of unitary construction with catheter hub 30 and will not be described in detail herein.

The first exhaust port 305 and the second exhaust port 306 are not necessary, and in some embodiments, the first exhaust port 305 and the second exhaust port 306 may be omitted, as shown in fig. 5, and glue can still be injected into the first glue cavity 303 and the second glue cavity 304 through the first glue dispensing port 301 and the second glue dispensing port 302, respectively, so that the catheter body 20 can be stably connected to the catheter hub 20 after the glue is cured.

Example 2

The same or similar parts of example 2 and example 1 will not be described in detail, and the main difference between them is that the catheter main body 20 of example 2 is a multi-lumen tube. Specifically, the catheter body 20 has multiple lumens within the body, e.g., at least 2 lumens within the body of the catheter body 20. It will be appreciated that at least one of the lumens of the catheter body 20 serves as a guidewire lumen 20b, and the other lumens serve as a loading and unloading lumen 20 a.

For ease of understanding, only 3 lumens are provided in the catheter body 20, and the 3 lumens each extend in the axial direction of the catheter body 20, as shown in fig. 6 and 7.

Specifically, the catheter main body 20 has 3 lumens, namely 1 guidewire lumen 20b and 2 loading and unloading lumens 20a, and the guidewire lumen 20b and the loading and unloading lumens 20a are separated from each other by a separation rib 201. Specifically, the guidewire lumen 20b is not in communication with the inflation and deflation lumen 20a, such that when the inflation and deflation lumen 20a inflates the inflatable balloon 10 with gas or liquid, the gas or liquid does not leak into the guidewire lumen 20 b.

As shown in fig. 6, the proximal end of the catheter body 20 is held within the inner lumen 30b of the catheter hub 30 by 2 collars 202, and the 2 collars 202 are located on the proximal and distal sides, respectively, of the inflation and deflation lumen 20a in communication with the inflation lumen 30 a. That is, in the axial direction of the inner cavity 30b of the catheter hub 30, the position where the filling and discharging cavity 20a communicates with the filling cavity 30a is located between the 2 collars 202, so that the 2 collars 202 respectively form the first resisting portion 110 and the second resisting portion 120, so as to prevent uncured glue in the first glue cavity 303 and the second glue cavity 304 from entering the position where the filling and discharging cavity 20a communicates with the filling cavity 30a, thereby effectively ensuring the smoothness of the passage of the filling and discharging cavity 30a and the filling and discharging cavity 20a for delivering gas or liquid to the balloon 10.

In other embodiments, 2 collars 202 may be part of catheter hub 30, i.e., integrally formed on the inner wall of catheter hub 30, so as to correspondingly form a boss structure and abut outer tube 21 and inner tube 22, respectively.

For example, referring to fig. 8, the catheter hub 30 is provided on the inner wall thereof with a first boss 202a and a second boss 202b abutting against the outer wall of the catheter body 20, the first boss 202a and the second boss 202b are disposed at intervals on the distal end side and the proximal end side of the position where the inflation and deflation cavity 20a communicates with the inflation cavity 30a, respectively, so that the catheter body 20 is partially spaced from the inner wall of the catheter hub 30 under the support of the first boss 202a and the second boss 202b, and the portion of the outer wall of the catheter body 20 spaced from the inner wall of the catheter hub 30 forms a first rubber chamber 303 and a second rubber chamber 304, respectively, and an intermediate chamber 301c, the first rubber chamber 303 is disposed on the distal end side of the first boss 202a, and the second rubber chamber 304 is disposed on the proximal end side of the second boss 202 b. The intermediate cavity 301c is located between the first boss 202a and the second boss 202b so that the filling cavity 30a communicates with the inflation and deflation cavity 20a through the intermediate cavity 301 c.

It should be noted that, with reference to fig. 6 and 8, the catheter main body 20 is provided with an inflation and deflation hole 203 communicated with the inflation and deflation cavity 20a, specifically, the inflation and deflation hole 203 penetrates through the outer wall of the catheter main body 20 and is communicated with the inflation and deflation cavity 20a, so that when the catheter main body 20 is located in the catheter hub 30, the inflation and deflation hole 203 on the catheter main body 20 is exposed at the communication position between the inner cavity 30b of the catheter hub 30 and the inflation cavity 30a, and the inflation and deflation cavity 20a can be communicated with the inflation cavity 30a of the catheter hub 30 through the inflation and deflation hole 203.

When 2 inflation/deflation lumens 20a are provided in the catheter main body 20, 2 inflation/deflation holes 203 for respectively communicating the 2 inflation/deflation lumens 20a with the inflation lumen 30a may be provided in the catheter main body 20. Or by removing part of the wall obstructing the 2 inflation and deflation cavities 20a, the 2 inflation and deflation cavities 20a are communicated with each other, and then the wall of the catheter main body 20 corresponding to at least one of the 2 inflation and deflation cavities 20a is provided with an inflation and deflation hole 20a so as to be communicated with the inflation cavity 30a of the catheter hub 30 through the inflation and deflation hole 20 a.

Accordingly, when a plurality of inflation and deflation lumens 20a are provided in the catheter main body 20, inflation and deflation holes 203 may be provided on the wall of the catheter main body 20 to extend through the respective inflation and deflation lumens 20a, so that the inflation and deflation lumens 20a communicate with the inflation lumen 30a of the catheter hub 30. The number of inflation and deflation lumens 20a in the catheter body 20 and the manner in which the inflation and deflation lumens 20a communicate with the inflation lumen 30a of the catheter hub 30 will not be described in detail herein.

The proximal side of the inflation lumen 20a is closed so that when the inflation lumen 20a is filled with gas or liquid, the gas or liquid cannot flow out of the proximal end of the inflation lumen 20a, but rather can only flow distally into the inflatable balloon 10 with the inflation lumen 20a to inflate the inflatable balloon 10. The proximal side of the loading and unloading chamber 20a may be sealed off by glue or by a seal (not shown) to seal off the proximal side of the chamber 20 a.

The structure of balloon catheter 100 will be further described below by way of example using glue to seal off the proximal side of the fill and release lumen 20 a.

In some embodiments, as shown in fig. 6, the proximal end of the catheter body 20 is opened with a hole 204 communicating with the loading and unloading cavity 20a, and when the catheter body 20 is mated with the catheter hub 30, the hole 204 communicates with the second glue cavity 304, so that when glue is injected into the second glue cavity 304 through the second glue dispensing port 302, the glue is injected into a part of the lumen of the loading and unloading cavity 20a close to the proximal end from the hole 204, and the proximal side of the loading and unloading cavity 20a is blocked, so that the proximal side of the loading and unloading cavity 20a is closed.

As shown in fig. 8, the proximal end of the catheter main body 20 is provided with a groove 205 communicating with the loading/unloading cavity 20a, and when the catheter main body 20 is mated with the catheter hub 30, the groove 205 communicates with the second glue cavity 304, so that when glue is injected into the second glue cavity 304 through the second glue dispensing opening 302, the glue fills the groove 205, and further seals the proximal end side of the loading/unloading cavity 20a, so that the proximal end side of the loading/unloading cavity 20a is closed.

The position of the hole 204 or the groove 205 formed in the catheter main body 20 is staggered with the second glue dispensing opening 302, so that the situation that the position of the hole 204 or the groove 205 is opposite to the second glue dispensing opening 302 to cause that the glue injected from the second glue dispensing opening 302 is injected into the filling and discharging cavity 20a too fast or too much from the hole 204 or the groove 205 is avoided, and the communication position between the filling and discharging cavity 20a and the filling cavity 30a is easily blocked. Preferably, the hole 204 or slot 205 of the catheter body 20 is located opposite the second glue dispensing opening 302 on the circumferential side of the catheter body 20, so that when glue is injected into the second glue lumen 304 from the second glue dispensing opening 302, the glue does not enter the loading and unloading lumen 20a directly from the hole 204 or slot 205, but rather, when the second glue lumen 304 is gradually filled, the glue enters the loading and unloading lumen 20a from the second glue lumen 304 through the hole 204 or slot 205, so that the second glue lumen 304 is filled as soon as possible before the glue blocks the proximal side of the loading and unloading lumen 20 a.

It should be noted that the sealing of the proximal end of the loading and unloading lumen 20a may not be performed simultaneously with the injection of glue into the second glue lumen 304 to join the catheter body 20 and the catheter hub 30. For example, the proximal side of the loading and unloading lumen 20a of the catheter body 20 may be first blocked off by glue or a seal before the catheter body 20 is assembled to the catheter hub 30. After the proximal side of the loading and unloading lumen 20a is sealed, the catheter body 20 is assembled to the catheter hub 30. In this mode of operation, since the proximal end of the inflation and deflation lumen 20a is already sealed, when glue is injected into the second glue lumen 304, the glue will not enter the inflation and deflation lumen 20a and block the communication between the inflation and

deflation lumens

20a and 30 a. In addition, when the loading/unloading cavity 20a is blocked in advance, the catheter main body 20 may be directly injected with glue or a sealing member may be attached to the proximal end of the loading/unloading cavity 20a of the catheter main body 20 without forming the hole 204 or the groove 205 communicating with the second glue cavity 304.

Example 3

Referring to fig. 9, embodiment 3 shows a catheter hub 30 without the boss or collar structure of embodiments 1 and 2, which also achieves the effect of blocking the uncured glue from flowing axially along the inner wall of catheter hub 30 to the location where the inflation and

deflation chambers

20a and 30a communicate with each other. The same or similar parts of embodiment 3 to embodiment 1 or embodiment 2 will not be described herein again.

Specifically, referring to fig. 10, the catheter main body 20 is a multi-lumen catheter body, and the catheter main body 20 includes a guidewire lumen 20b and a plurality of charging and discharging lumens 20a arranged around the guidewire lumen 20b at intervals. The number of the charging and discharging chambers 20a may be 2 or more than 2.

As shown in fig. 9 and 11, the outer wall of the catheter main body 20 is provided with an annular groove 206 along the circumferential direction thereof, and the annular groove 206 forms a plurality of openings in the catheter main body 20, the plurality of openings being respectively communicated with the plurality of charging and discharging chambers 20 a. When the catheter body 20 is assembled in the catheter hub 30, the annular groove 206 is in communication with the filling lumen 30a of the catheter hub 30, such that the filling lumen 30a is in communication with the plurality of inflation and deflation lumens 20a through the plurality of openings formed in the catheter body 20 by the annular groove 206, such that gas or liquid injected from the filling lumen 30a can flow into the inflation and deflation lumen 20a, thereby inflating the expandable balloon 10 connected to the distal end of the catheter body 20 with gas or liquid using the inflation and deflation lumen 20 a.

Further, as shown in fig. 10, the inflation and deflation cavities 20a of the catheter main body 20 are uniformly distributed around the circumference of the guidewire cavity 20b around the axial direction of the catheter main body 20, so that when the annular groove 206 is formed on the catheter main body 20, the openings formed by the annular groove 206 at the position corresponding to the inflation and deflation cavity 20a of the catheter main body 20 are uniformly arranged around the circumference of the catheter main body 20, and further when the inflation cavity 30a of the catheter seat 30 fills the annular groove 206 with gas or liquid, the gas or liquid is stably conveyed into the expandable balloon 10 located in the catheter main body 20 along each inflation and deflation cavity 20a, so that the gas or liquid can be uniformly injected into the expandable balloon 10, and the problem that the speed of injecting the gas or liquid into one side of the expandable balloon 10 is too different from the speed of injecting the gas or liquid into the other side, so that the gas or liquid cannot be radially diffused synchronously, which affects the.

With continued reference to FIG. 10, the catheter body 20 includes 3 inflation and deflation lumens 20a, and the 3 inflation and deflation lumens 20a are evenly distributed around the circumference of the guidewire lumen 20b about the axial direction of the catheter body 20.

The lumen 30b of the catheter hub 30 is a cylindrical space, and the catheter body 20 is inserted into the lumen 30b of the catheter hub 30. The catheter body 20 and the inner wall of the catheter hub 30 may be in an interference fit, i.e. the outer wall of the catheter body 20 abuts against the inner wall of the catheter hub 30. The annular groove 206 of the catheter body 20 will place the inflation lumen 30a of the catheter hub 30 in communication with the respective inflation and deflation lumens 20a of the catheter body 20.

In this embodiment, as shown in fig. 9, a stepped groove 30c is formed at the distal end of the catheter hub 30, so that when the catheter main body 20 is fitted with the inner wall of the catheter hub 30, a first glue cavity 303 is formed between the wall surrounding the stepped groove 30c and the outer wall of the catheter main body 20, and correspondingly, a first glue dispensing opening 301 communicated with the first glue cavity 303 is formed in the catheter hub 30, so that glue can be injected into the first glue cavity 303 from the first glue dispensing opening 301, and after the glue is cured, the bonding force between the catheter main body 20 and the catheter hub 30 can be enhanced, so that the catheter main body 20 is not easily pulled out from the inner cavity 30b of the catheter hub 30.

Due to the interference fit between the outer wall of the catheter main body 20 and the inner wall of the catheter hub 30, when glue is injected into the first glue cavity 303, at the proximal end of the stepped groove 30c, the glue is not easy to flow between the outer wall of the catheter main body 20 and the inner wall of the catheter hub 30, that is, at the interference fit position between the catheter main body 20 and the inner wall of the catheter hub 30, the first resisting portion 110 and the second resisting portion 120 are formed, so as to reduce the risk that the glue blocks the filling and discharging cavity 20 a.

Referring to fig. 9 and 11, the proximal end of the catheter body 20 is formed with an annular notch 207, and the bottom of the annular notch 207 is formed by the walls that enclose the guidewire lumen 20 b. When catheter body 20 abuts the inner wall of catheter hub 30, a second glue lumen 304 is formed at annular recess 207. The catheter base 30 is provided with a second glue dispensing opening 302 communicated with the second glue cavity 304, so that glue can be injected into the second glue cavity 304 through the second glue dispensing opening 302, and the catheter main body 20 is more stably connected with the catheter base 30 after the glue is cured. Because the second glue cavity 304 is formed at the annular notch 207 of the catheter main body 20, the cured glue is embedded at the annular notch 207 of the catheter main body 20, so that the catheter main body 20 can be well axially limited, and the connection stability between the catheter main body 20 and the catheter hub 30 is further improved.

The annular groove 206 and the annular recess 207 may be identical in structure, except that the annular groove 206 and the annular recess 207 are located differently on the catheter body 20, so that when the catheter body 20 is assembled to the catheter hub 30, the annular groove 206 communicates with the filling lumen 30a of the catheter hub 30 and the filling and removing lumen 20a of the catheter body 20, and the annular recess 207 is adapted to the injection requirements of glue, forming a second glue lumen 304 in the inner lumen of the catheter body 20.

The annular groove 206 and the annular recess 207 can be machined in the following way: 1. circumferentially peeling off the partial structure of the wall of catheter body 20 that encloses the charging and discharging lumen 20a, 2, pressing the multi-lumen tube threaded into the mandrel in guidewire lumen 20b in one go using a hot press, hot weld process to form catheter body 20 with annular groove 206 or annular notch 207.

Referring to FIG. 11, the proximal side of the annular groove 206 is provided with a first sealing strip 206a, and the proximal side of the annular groove 206 is sealed by the first sealing strip 206a, so that when gas or liquid is injected into the inflation and deflation lumen 20a from the inflation and deflation lumen 30a, the gas or liquid can only flow distally along the inflation and deflation lumen 20a into the expandable balloon 10 attached to the distal end of the catheter body 20.

In some embodiments, the distal side of annular recess 207 is provided with a second sealing band 207a, which second sealing band 207a is capable of functioning to seal the distal side of annular recess 207. Since the connection between the filling lumen 30a of the catheter hub 30 and the inflation and deflation lumen 20a of the catheter main body 20 is located at the distal side of the second glue lumen 304 corresponding to the annular recess 207, the second sealing strip 207a seals the distal side of the annular recess 207, which prevents the gas or liquid injected from the filling lumen 30a from flowing proximally along the inflation and deflation lumen 20a into the annular recess 207, that is, the second sealing strip 207a seals the inflation and deflation lumen 20a at the proximal side of the connection between the filling lumen 30a and the inflation and deflation lumen 20a, so that the gas or liquid injected from the filling lumen 30a flows distally along the inflation and deflation lumen 20a into the interior of the expandable balloon 10 after entering the inflation and deflation lumen 20 a.

In addition, the second sealing strip 207a disposed at the distal end of the annular recess 207 can prevent the uncured glue injected into the second glue cavity 304 from flowing to the connection between the filling cavity 30a and the inflation and deflation cavity 20a, which may block the passage of the inflation gas or liquid from the inflation and deflation cavity 20a to the expandable balloon 10. The second sealing strip 207a can prevent the glue in the second glue cavity 304 from flowing into the filling and discharging cavity 20a, so that the glue consumption can be saved, and the waste of the glue can be avoided.

In some embodiments, a third sealing band 207b is disposed on the proximal side of the annular recess 207, and the third sealing band 207b can seal the proximal side of the annular recess 207, thereby preventing uncured glue injected into the second glue cavity 304 from flowing proximally into the proximal end of the fill and unload cavity 20a and causing waste of glue.

In some embodiments, both the distal side and the proximal side of the annular recess 207 are provided with a sealing band, more precisely, the distal side of the annular recess 207 is provided with a second sealing band 207a and the proximal side is provided with a third sealing band 207 b. With this arrangement, the filling and discharging cavity 20a and the second glue cavity 304 can be isolated by using the sealing tape, so as to prevent the glue from flowing into the filling and discharging cavity 20a from the second glue cavity 304. The first sealing band 206a, the second sealing band 207a and the third sealing band 207b may be integrally formed to the catheter body 20 by heat and pressure.

It can be understood that, in this embodiment, the catheter hub 30 may also be provided with the first exhaust port 305 and the second exhaust port 306, so that when glue is injected into the first glue cavity 303, the first exhaust port 305 can have a better exhaust effect, so that the glue can be injected into the first glue cavity 303 more smoothly, and bubbles are not easily formed, so as to enhance the bonding effect of the glue between the catheter main body 20 and the catheter hub 30. Accordingly, the second air outlet 306 can be adapted to the air outlet requirement of the second glue cavity 304, and will not be described herein.

It should be noted that the balloon catheter 100 of examples 1 to 3 has a similar working principle, although the structure is slightly different.

To facilitate understanding of the working principle of the balloon catheter 100, the following description will be given by taking the balloon catheter 100 shown in fig. 1 as an example.

Referring to FIG. 1, inflation lumen 30a of catheter hub 30 communicates with lumen 30b of catheter hub 30, and inflation and deflation lumen 20a of catheter body 20 communicates with inflation lumen 30a via lumen 30b of catheter hub 30. Because the proximal side and the distal side of the communication position of the filling cavity 20a and the filling cavity 30a are respectively provided with the inner tube collar 22a and the outer tube collar 21a, during the process of injecting glue into the first glue cavity 303 and the second glue cavity 304 from the first glue dispensing opening 301 and the second glue dispensing opening 302, the uncured glue cannot flow to the position where the filling cavity 30a is communicated with the filling cavity 20a under the obstruction of the inner tube collar 22a and the outer tube collar 21a, so that the glue is prevented from entering the proximal end of the filling cavity 20a to block a passage for injecting gas or liquid into the expandable balloon 10 at the distal end of the catheter main body 20.

Since the proximal and distal sides of the communicating position of the inflation and

deflation cavities

20a and 30a are sealed by glue, when the inflation cavity 30a communicates with an external device, when gas or liquid is injected into the inflation cavity 30a through the external device, the gas or liquid will flow into the interior of the inflatable balloon 10 located at the distal end of the catheter main body 20 through the inflation and deflation cavity 20a communicating with the inflation cavity 30a, so as to realize the effect of inflating the inflatable balloon 10 and expanding the inflatable balloon 10.

It should be noted that the distal end of the catheter body 20 is provided with one or more inflation/deflation ports 20c, the inflation/deflation port 20c is communicated with the inflation/deflation cavity 20a, and the inflation/deflation port 20c is located inside the inflatable balloon 10 along with the engagement of the catheter body 20 with the inflatable balloon 10, so that the gas or liquid inflated in the inflation/deflation cavity 20a can be transported to the distal end of the catheter body 20 along the inflation/deflation cavity 20a and enter the inside of the inflatable balloon 10 from the inflation/deflation port 20c to inflate the inflatable balloon 10.

The section of the catheter body 20 distal to the interior of the expandable balloon 10 may be provided with a visualization ring 102 so that when the expandable balloon 10 is implanted in a blood vessel, the expandable balloon 10 may be pushed into place according to the visualization ring 102. The number of the developing rings 102 may be 1 or more than 1, and is not limited herein.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A balloon catheter, comprising:

2. The balloon catheter according to claim 1, wherein the first abutment is disposed coaxially with the second abutment.

3. The balloon catheter according to claim 1, wherein the wall of the catheter holder is further provided with a first exhaust port communicated with the first rubber cavity and a second exhaust port communicated with the second rubber cavity; the first air outlet is used for exhausting air in the first glue cavity when fluid is injected through the first glue dispensing opening; and when fluid is injected through the second dispensing port, the second exhaust port is used for exhausting gas in the second dispensing cavity.

4. A balloon catheter according to claim 1, wherein the catheter main body comprises an inner tube and an outer tube both hollow inside, the outer tube being sleeved outside the inner tube, the outer tube having an inner diameter larger than an outer diameter of the inner tube, the proximal end of the inner tube protruding from the proximal end of the outer tube; the first resisting part and the second resisting part are both annular pieces, the first resisting part is sleeved on the near end of the outer tube and is abutted against the inner wall of the catheter seat, and the second resisting part is sleeved on the near end of the inner tube and is abutted against the inner wall of the catheter seat.

5. The balloon catheter according to claim 4, wherein a first insertion hole and a second insertion hole are coaxially connected in the inner cavity of the catheter hub, the inner diameter of the first insertion hole is larger than that of the second insertion hole, the first insertion hole is used for accommodating the proximal end of the outer tube and the first abutting portion, and the second insertion hole is used for accommodating the proximal end of the inner tube and the second abutting portion.

6. The balloon catheter according to claim 1, wherein the catheter body has at least 2 lumens in the catheter body, the at least 2 lumens each extend along the axial direction of the catheter body, at least 1 lumen forms the inflation/deflation chamber, and the catheter body is provided with an inflation/deflation hole penetrating through the inflation/deflation chamber, and the inflation/deflation hole is used for communicating the inflation/deflation chamber with the inflation chamber of the catheter hub.

7. A balloon catheter according to claim 6, wherein the inner wall of the catheter hub has first and second bosses abutting against the outer wall of the catheter body, the first and second bosses being spaced apart on proximal and distal sides of the inflation and deflation lumen, the catheter body being spaced apart from the inner wall of the catheter hub under the influence of the first and second bosses to form the first and second glue lumens, the first glue lumen being located on the distal side of the first boss and the second glue lumen being located on the proximal side of the second boss.

8. The balloon catheter according to claim 6, wherein a hole or a groove communicating the filling and discharging cavity with the second glue cavity is formed in the wall of the catheter body, so that when glue is injected into the second glue cavity, the glue flows into the proximal end side of the filling and discharging cavity from the hole or the groove and blocks the proximal end side of the filling and discharging cavity;

9. The balloon catheter according to claim 6, wherein the outer wall of the catheter main body abuts against the inner wall of the catheter holder to form the first abutting portion and the second abutting portion, the inflation/deflation chambers of the catheter main body are surrounded on the periphery of the guide wire chamber, the proximal end of the catheter main body is provided with at least one annular groove, the groove bottom of the annular groove is formed by a wall surrounding the guide wire chamber, the annular groove is communicated with the inflation chamber of the catheter holder and forms a plurality of openings on the catheter main body, and the inflation chamber is respectively communicated with the inflation/deflation chambers through the plurality of openings.

10. The balloon catheter according to claim 9, wherein a stepped groove is formed at the distal end of the catheter holder, and the first glue cavity is formed between a wall enclosing the stepped groove and the outer wall of the catheter main body; the proximal end of the catheter main body is provided with an annular notch, the bottom of the annular notch is formed by a wall which encloses to form the guide wire cavity, and when the catheter main body is abutted against the inner wall of the catheter seat, the annular notch forms the second rubber cavity; a first sealing band is arranged on the proximal side of the annular groove, or a second sealing band is arranged on the distal side of the annular recess.