CN217090668U

CN217090668U - Bending tube and endoscope

Info

Publication number: CN217090668U
Application number: CN202121450872.XU
Authority: CN
Inventors: 严航
Original assignee: Anqing Medical Co Ltd
Current assignee: Anqing Medical Co Ltd
Priority date: 2021-06-28
Filing date: 2021-06-28
Publication date: 2022-08-02
Anticipated expiration: 2031-06-28

Abstract

The utility model provides a bending tube and endoscope, bending tube wherein, include: the clamping part is fixedly arranged at the first end of the bending section, the hard section is fixedly arranged at the second end of the bending section, the bending section is provided with a plurality of spiral seam units which are not connected with each other, and the spiral seam units comprise a plurality of spiral seam units in a first rotation direction and a plurality of spiral seam units in a second rotation direction; the spiral seam unit comprises two main seams and a connecting seam, wherein the two main seams are a first main seam and a second main seam respectively, the first end of the connecting seam is connected with one end of the first main seam, and the second end of the connecting seam is connected with one end of the second main seam.

Description

Bending tube and endoscope

Technical Field

The utility model relates to the field of medical equipment, especially, relate to a bending tube and endoscope.

Background

With the development of science and technology, endoscopes have been widely used in the medical field, which are one of important tools for examining internal organs of the human body. From 1806, it was found that to date, the development of endoscopes has gone through the following four stages: hard tube type endoscope, semi-flexible endoscope, fiber endoscope, ultrasonic endoscope and electronic endoscope. Nowadays, the types of endoscopes are mainly classified into hard tube type endoscopes and flexible tube type endoscopes. The hard tube type endoscope has high strength and good insertability, but is easy to stab the inner wall, and only can perform operations with relatively definite focus positions because the lens cannot rotate. In some operations in which the lesion position is unclear, the direction of observation needs to be constantly adjusted, and therefore, a soft endoscope needs to be used.

Flexible endoscopes can employ multi-segment curved tubes, in which a continuous helical cut is typically used, thereby forming a continuous helical slit. However, it is difficult to secure the rigidity during rotation by the continuous spiral slit.

SUMMERY OF THE UTILITY MODEL

The utility model provides a bending tube and an endoscope, which solve the problem that the rigidity is difficult to be ensured.

According to the utility model discloses a first aspect provides a bent tube, include: the clamping part is fixedly arranged at the first end of the bending section, the hard section is fixedly arranged at the second end of the bending section, the bending section is provided with a plurality of spiral seam units which are not connected with each other, and the spiral seam units comprise a plurality of spiral seam units in a first rotation direction and a plurality of spiral seam units in a second rotation direction;

the spiral seam unit comprises two main seams and a connecting seam, the two main seams are a first main seam and a second main seam respectively, the first end of the connecting seam is connected with one end of the first main seam, and the second end of the connecting seam is connected with one end of the second main seam;

along the circumferential target hour hand direction of the bending section, the first main gap and the second main gap are distributed on two sides of the connecting gap; the target hour hand direction is clockwise or anticlockwise;

one end of the two ends of the connecting gap is close to the clamping portion, and the other end of the two ends of the connecting gap is far away from the clamping portion; wherein:

in the spiral seam unit in the first rotation direction, a first end of the connecting seam is an end close to the clamping part, and a second end of the connecting seam is an end far away from the clamping part;

in the spiral seam unit of second spiral direction, the first end of connecting gap is for keeping away from the one end of joint portion, the second end of connecting gap is for being close to the one end of joint portion.

Optionally, a plurality of spiral seam units have formed a plurality of unit groups, and every unit group contains two spiral seam units, follows the axle center direction of crooked section, the axial position of two spiral seam units in same unit group is the same, just a plurality of unit groups interval distribution in proper order.

Optionally, along the circumferential direction, the circumferential positions of two spiral seam units in the same unit group are different by half of the circumference.

Optionally, when the bending tube is not bent, the two spiral seam units in the same unit set are symmetrical about a longitudinal section of the bending section passing through the axis.

Optionally, for any two adjacent unit groups with the same rotation direction, the circumferential positions of the spiral seam units in the two unit groups along the circumferential direction are different by 1/4 circumferences.

Optionally, the bending section includes a first bending section and a second bending section, the clamping portion is disposed at a first end of the first bending section, a second end of the first bending section is connected to a first end of the second bending section, and the hard section is disposed at a second end of the second bending section;

the interclass interval between adjacent cell groups in the first bending section is a first interclass interval;

the inter-group interval between adjacent unit groups in the second bending section is a second inter-group interval;

the first inter-group spacing is greater than the second inter-group spacing.

Optionally, the main slit is formed between a first slit edge and a second slit edge, and the first slit edge and the second slit edge both extend along the circumferential direction of the bending section;

the first slit edge and the second slit edge have a main slit interval along an axial center direction of the bent section.

the main gap interval of the spiral gap unit in the first bending section is a first main gap interval;

the main gap interval of the spiral gap unit in the first bending section is a second main gap interval;

the first main slit interval is smaller than the second main slit interval.

the first bending section comprises a first subsection and a second subsection, the second bending section comprises a third subsection and a fourth subsection, the first subsection, the second subsection, the third subsection and the fourth subsection are sequentially connected, the clamping part is arranged at one end, far away from the second subsection, of the first subsection, and the hard section is arranged at one end, far away from the third subsection, of the fourth subsection;

the first subsection is provided with a spiral seam unit in the first rotation direction; the second subsection is provided with a spiral seam unit in the second rotation direction; the third subsection is provided with a spiral seam unit in the first rotation direction; the fourth subsection is provided with a spiral seam unit in the second rotation direction; or:

the first subsection is provided with a spiral seam unit in the second rotary direction; the second subsection is provided with a spiral seam unit in the first rotation direction; the third subsection is provided with a spiral seam unit in the second rotation direction; and the fourth subsection is provided with a spiral seam unit in the first rotation direction.

Optionally, when the bent section is not bent, the first sub-section and the second sub-section are symmetrical with respect to a cross section of the bent section at a corresponding position; the third subsection and the fourth subsection are symmetrical about the cross section of the corresponding position of the bent section.

Optionally, the curved tube further includes an outer tube, the outer tube is disposed outside at least a portion of the structure of the clamping portion, the curved section, and the hard section, and the outer tube includes one or more layers of polymer materials.

According to a second aspect of the present invention, there is provided an endoscope comprising the curved tube of the first aspect and its alternatives.

The utility model provides an among crooked pipe and the endoscope, the spiral seam in the crooked pipe has adopted a plurality of spiral seam units that do not connect each other, and then, compare in continuous spiral seam, the utility model discloses can effectively improve the rigidity, simultaneously, because each spiral seam unit has formed the spiral seam unit of first rotation direction and the spiral seam unit of second rotation direction, can improve the coaxial rotation rigidity of pivoted in, still help improving the even deflection of each direction.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.

Fig. 1 is a schematic structural view of a bending tube according to an embodiment of the present invention;

fig. 2 is a first schematic structural diagram of a spiral seam unit according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a spiral seam unit according to an embodiment of the present invention;

fig. 4 is a partial structural diagram of a bending tube according to an embodiment of the present invention;

fig. 5 is a schematic view of a partial structure of a bending tube according to an embodiment of the present invention;

fig. 6 is a first schematic size diagram of the unit set and the spiral slit unit according to an embodiment of the present invention;

fig. 7 is a schematic size diagram of the unit set and the spiral slit unit according to an embodiment of the present invention.

Description of reference numerals:

1-a clamping part;

2-hard segment;

3-bending section;

300-a spiral seam unit;

301-first major gap

302-second major gap

303-connection gap

30-unit group;

31-first subsection

32-second subsection

33-a third sub-section;

34 a fourth subsection.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it should be understood that the terms "upper portion", "lower portion", "upper end", "lower surface", "upper surface", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

In the description of the present invention, "plurality" means a plurality, such as two, three, four, etc., unless specifically limited otherwise.

In the description of the present invention, unless explicitly stated or limited otherwise, the terms "connected" and the like are to be understood broadly, and may for example be fixedly connected, detachably connected, or integrated; can be mechanically connected, electrically connected or can communicate with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

The technical solution of the present invention will be described in detail with specific examples. The following several specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments.

The embodiment of the utility model provides a crooked pipe can be for being applied to the crooked pipe of endoscope, also does not exclude the scheme of being applied to other devices with it. The bending tube can be a controllable bending tube or a passive bending tube in an endoscope, without excluding other possibilities. It is clear that any bending tube applied to medical instruments does not depart from the scope of the embodiments of the present invention.

Referring to fig. 1, the bending tube includes: joint portion 1, crooked section 3 and stereoplasm section 2, joint portion 1 is fixed to be located the first end of crooked section 3, stereoplasm section 2 is fixed to be located the second end of crooked section 3.

Joint portion 1 wherein, can understand for the arbitrary structure or the combination of structure that can realize the external joint of crooked pipe, simultaneously, joint portion 1 can be integrative with crooked section 3, and then adopts the same material, also does not get rid of the scheme of non-integrative and/or adopt different materials, and in the part example, joint portion 1 can be equipped with the hole, and then, can realize the control of crooked pipe based on the line that passes the hole. Further, the clip portion 1 may have a tubular shape (e.g., a circular tubular shape).

Wherein stereoplasm section 2, can understand for adopting the stereoplasm and can't (or be difficult to) crooked pipeline section, simultaneously, stereoplasm section 2 can be integrative with crooked section 3, and then adopt the same material, also do not exclude non-integrative and/or adopt the scheme of different materials, in the part example, stereoplasm section 2 can be equipped with the hole, and then, can realize controlling based on the line that passes the hole, in addition, stereoplasm section 2 can be sharp tubulose (for example, the pipe shape), stereoplasm section 2 still can be connected with other pipes or devices.

In the embodiment of the present invention, please refer to fig. 2 to fig. 7, the bending section 3 is provided with a plurality of spiral seam units 300 that are not connected to each other, and the spiral seam units 300 include a plurality of spiral seam units 300 with a first rotation direction and a plurality of spiral seam units 300 with a second rotation direction; if the spiral seam unit shown in fig. 2 is regarded as a spiral seam unit in a first rotation direction, the spiral seam unit corresponding to the spiral seam unit shown in fig. 3 can be regarded as a spiral seam unit in a second rotation direction; if the spiral seam unit shown in fig. 2 is regarded as a spiral seam unit with the second rotation direction, the spiral seam unit corresponding to the spiral seam unit shown in fig. 3 can be regarded as a spiral seam unit with the first rotation direction.

In the drawings of fig. 4-6, each of the drawings shows the configuration of a first side and a second side of the bent tube, respectively, wherein the first side and the second side are opposite (or can be understood as facing away from) each other.

The spiral seam in the crooked pipe has adopted a plurality of spiral seam units that do not connect each other, and then, compares in continuous spiral seam, the utility model discloses can effectively improve the rigidity.

The spiral seam unit 300 comprises two main seams and a connecting seam, wherein the two main seams are a first main seam 301 and a second main seam 302 respectively, a first end of the connecting seam 303 is connected with one end of the first main seam 301, and a second end of the connecting seam 303 is connected with one end of the second main seam 303;

along the circumferential direction of the curved section in the target hour hand direction, the first main gap 301 and the second main gap 302 are distributed on two sides of the connecting gap; the target hour hand direction is clockwise or anticlockwise;

one end of the two ends of the connecting gap is close to the clamping part 1, and the other end of the two ends of the connecting gap is far away from the clamping part 1; wherein:

referring to fig. 2, in the first spiral seam unit 300, a first end of the connection gap 303 (i.e., an end connected to the first main gap 301) is an end close to the fastening portion 1, and a second end of the connection gap 303 (i.e., an end connected to the second main gap 302) is an end far from the fastening portion 1; further, a short spiral shape of one form can be formed, and it can be formed into a spiral shape of the first rotation direction.

Referring to fig. 3, in the second spiral seam unit 300, a first end of the connection gap 303 (i.e., an end connected to the first main gap 301) is an end far away from the fastening portion 1, and a second end of the connection gap 303 (i.e., an end connected to the second main gap 302) is an end close to the fastening portion 1; further, a short spiral shape of one form may be formed, and it may be formed into a spiral shape of a second sense of rotation.

The spiral seam units and the sizes can be the same, and the embodiment of the invention does not exclude that the shapes and/or the sizes of the partial spiral seam units are different. In the illustrated example, the connecting slit 303 extends in the axial direction of the bending tube, and the main slit extends in the axial direction of the bending tube.

Therefore, in the above scheme, since each spiral seam unit forms the spiral seam unit in the first rotation direction and the spiral seam unit in the second rotation direction, the coaxial rotation rigidity of rotation can be improved, and the uniform deformation amount in each direction can be improved.

In the illustrated example, for the main slit therein, the main slit is formed between a first slit edge and a second slit edge, both of which extend in the circumferential direction of the curved section; in the axial direction of the bending section, the first slit edge and the second slit edge have a main slit interval (which may be, for example, the main slit interval d shown in fig. 7). The main slit can furthermore be understood as a wide slit.

In the illustrated example, for the connecting slit therein, it may be formed between two slit edges extending in the axial direction of the bending section; the two slit edges may be free of gaps in the circumferential direction of the curved tube, and the connecting slit may be a slit, in some cases with a certain distance between the two slit edges.

Through the design of extending along the circumferential direction and the axis direction, the opening and closing of the main gap during bending can be conveniently realized, the bending stability is effectively ensured, and the radial contraction and expansion of the pipe can be avoided. Meanwhile, the scheme can further improve the coaxial rotation rigidity.

In other examples, the main slit may have an inclination angle with the axial direction and the circumferential direction, and the connecting slit may have an inclination angle with the axial direction and the circumferential direction.

In one embodiment, referring to fig. 4 to 6, the plurality of spiral slit units form a plurality of unit sets 30, and each unit set 30 includes two spiral slit units 300.

Specifically, along the axial direction of the bending section, the axial positions of the two spiral slit units 300 in the same unit group 30 are the same, which can also be understood as follows: when not bent, the distance between the two spiral seam units 300 and the clamping part 1 in the same unit group 30 is the same, and the distance between the two spiral seam units 300 and the hard segment 2 in the same unit group 30 is the same.

By way of further example, the circumferential positions of two spiral slit elements 300 in the same element group 30 are different by half a circumference in the circumferential direction. Taking fig. 6 as an example, wherein a circumferential orientation of 0 °, 180 °, 360 ° (i.e. 0 °) is assumed, it can be seen that:

the difference in circumferential orientation between two connecting slits 303 in the same set 30 is 180 ° (180+ a3) ° -a3 °;

the difference in circumferential orientation between the ends of the two first main slits 301 in the same set 30 of cells is 180 ° (180+ a2) ° -a2 °;

the difference in circumferential orientation between the ends of the two second main slits 302 in the same set 30 of cells is 180 ° (180+ a1) ° -a1 °;

corresponding to the circumferential orientation, a 180 degree difference may be understood as one-half of the circumference of the curved segment (i.e., 1/2C, where C represents the circumference).

Further, a single helical seam element may cover at least half of the circumference in the circumferential direction. In one example, half of the circumference may be 4.84mm, for example, and correspondingly, the difference between the circumferential distances of the two ends of the single spiral slit unit may be 4.985mm

Specifically, the plurality of cell groups 30 are sequentially spaced at intervals, such as an inter-group interval L shown in fig. 7. The interclass interval L between each group of cells 30 may or may not vary.

In one embodiment, please refer to fig. 1, the bending section 3 includes a first bending section (e.g., a combination of a first subsection 31 and a second subsection 32) and a second bending section (e.g., a combination of a third subsection 33 and a fourth subsection 34), the fastening portion 1 is disposed at a first end of the first bending section, a second end of the first bending section is connected to a first end of the second bending section, and the hard section 2 is disposed at a second end of the second bending section.

Still further, the first bending section includes a first subsection 31 and a second subsection 32, the second bending section includes a third subsection 33 and a fourth subsection 34, the first subsection 31, the second subsection 32, the third subsection 33 and the fourth subsection 34 are sequentially connected, the clamping portion 1 is arranged at one end of the first subsection 31 far away from the second subsection 32, and the hard section 2 is arranged at one end of the fourth subsection 34 far away from the third subsection 33;

in the example shown in fig. 1 to 7, the first subsection 11 is provided with the spiral seam unit (such as the spiral seam unit shown in fig. 3) with the second rotation direction; the second subsection 32 is provided with the spiral seam unit (such as the spiral seam unit shown in fig. 2) with the first rotation direction; the third subsection 33 is provided with the spiral seam unit (such as the spiral seam unit shown in fig. 3) with the second rotation direction; the fourth subsection 34 is provided with the spiral seam unit (such as the spiral seam unit shown in fig. 2) with the first rotation direction.

In an example not shown in the drawings, the first subsection is provided with a spiral seam unit in the first rotation direction; the second subsection is provided with a spiral seam unit in the second rotation direction; the third subsection is provided with a spiral seam unit in the first rotation direction; and the fourth subsection is provided with the spiral seam unit in the second rotation direction.

And further:

the interclass interval between adjacent cell groups in the first bending section is a first interclass interval; namely: the inter-group intervals in the first subsegment 31 and the second subsegment 32 are the same and are both the first inter-group intervals;

the inter-group interval between adjacent unit groups in the second bending section is a second inter-group interval; namely: the inter-group intervals in the third subsegment 33 and the fourth subsegment 34 are the same and are the third inter-group intervals;

the main slit interval of the spiral slit unit 300 in the first bending section is a first main slit interval; namely: the main gap intervals in the first subsection 31 and the second subsection 32 are the same and are both the first main gap interval;

the main gap interval of the spiral slit unit 300 in the first bending section is a second main gap interval; namely: the main gap intervals in the third subsection 31 and the second subsection 32 are the same and are both the second main gap interval;

wherein:

the first inter-group spacing (e.g., characterizable as L1) may be less than the second inter-group spacing (e.g., characterizable as L2). For example: the first inter-group spacing L1 may be 0.5mm and the second inter-group spacing L2 may be 0.6 mm.

The first primary slot spacing (e.g., characterizable as D1) may be less than the second primary slot spacing (e.g., characterizable as D2). For example: the first main slot spacing D1 may be 0.5mm and the second main slot spacing D2 may be 0.6 mm.

It can be seen that the first inter-group spacing may be the same as the first main slit spacing and the second inter-group spacing may be the same as the second main slit spacing.

Through the size design, can effectively ensure: the bending capacity of each part in the axis center direction of the first bending section is the same, the bending capacity of each part in the axis center direction of the second bending section is the same, and the bending capacity of the first bending section is higher than that of the second bending section, so that the gradual change of the bending capacity can be realized, the effect of different hardness can be realized, and the motion and control requirements of the bending pipe after entering the human body can be met. Meanwhile, for each bending section with bending capacity, two sub-sections with rotary directions are provided, and the coaxial rotation rigidity during rotation can be effectively improved. The bending capacity can be represented by the maximum deformation, the bending radius, the bending difficulty and the stress.

Specifically, for any two adjacent unit groups with the same rotation direction, the circumferential positions of the spiral seam units in the two unit groups along the circumferential direction have a difference of 1/4 circumferences; taking fig. 6 as an example, wherein a circumferential orientation of 0 °, 180 °, 360 ° (i.e. 0 °) is assumed, it can be seen that:

the difference in the circumferential directions is (180+ b +90) ° (b +90) ° -b ° -90 ° -with reference to the positions of the connecting slit 303 in the adjacent two spiral slit units

Corresponding to the circumferential orientation, the 90 degree difference is understood to be 1/4 circumferences of the curved segment (i.e., 1/4C, where C represents the circumference).

By the size design shown in fig. 6, it can be ensured that each slit can fully cover various positions in the circumferential direction, and the balance of the bending capacity at each position in the circumferential direction can be ensured, so that a more uniform deformation amount can be provided.

In one embodiment, when the bent pipe is not bent, two spiral seam units in the same unit set are symmetrical about a longitudinal section of the bent section passing through the axis. Taking fig. 4 to 6 as an example, the structure of the first side and the structure of the second side are the same in each figure.

In addition, the lengths of the first main slit and the second main slit may be the same, and the included angles between the first main slit and the second main slit and the connecting slit are also the same.

When the bending stretching and the bending compression are carried out, the structure which is symmetrical up and down can effectively improve more deformation.

In one embodiment, when the bent section is not bent, the first sub-section and the second sub-section are symmetrical about the cross section of the corresponding position of the bent section; the third subsection and the fourth subsection are symmetrical about the cross section of the corresponding position of the bent section.

Therefore, in the scheme, the coaxial rotation rigidity during rotation can be further effectively improved.

In addition, through the effective combination of the main gap and the connecting gap, the deformation of the whole bending section is large and the stress is uniform when the bending section is bent, so the bending radius can be smaller and softer.

In one embodiment, the bending tube may further include an outer tube, the outer tube is disposed outside at least some of the clamping portion, the bending section, and the hard section, for example: the outer tube can be sleeved outside the bending section, the clamping part and the hard section, can be sleeved outside at least part of the bending section, and can be sleeved outside at least part of the bending section and the hard section.

The outer tube may, for example, comprise a single layer or multiple layers of a polymeric material, which has the positive effects of good performance, ease of manufacture, low cost, etc.

In one embodiment, the spiral seam unit may be formed by cutting the base material, and the hardness of the bent tube may be changed by changing the size of the cut blank.

In the description herein, references to the terms "an embodiment," "an example," "a specific implementation," "an example," etc., mean that a particular feature, structure, material, or characteristic described in connection with the example or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims

1. A curved tube, comprising: the clamping part is fixedly arranged at the first end of the bending section, the hard section is fixedly arranged at the second end of the bending section, the bending section is provided with a plurality of spiral seam units which are not connected with each other, and the spiral seam units comprise a plurality of spiral seam units in a first rotation direction and a plurality of spiral seam units in a second rotation direction;

in the spiral seam unit with the first rotation direction, the first end of the connecting seam is the end close to the clamping part, and the second end of the connecting seam is the end far away from the clamping part;

2. The curved pipe according to claim 1, wherein the plurality of spiral slit units form a plurality of unit groups, each unit group comprises two spiral slit units, the axial positions of the two spiral slit units in the same unit group are the same along the axial direction of the curved section, and the plurality of unit groups are sequentially distributed at intervals.

3. The curved pipe according to claim 2, wherein the circumferential positions of two helical slit elements in the same set of elements differ by half a circumference in the circumferential direction.

4. The curved tube according to claim 2, wherein the two helical slit units in the same set of units are symmetrical about a longitudinal section of the curved section through the axial center when the curved tube is not curved.

5. The curved pipe according to claim 2, wherein for any two adjacent sets of cells having the same rotational direction, the circumferential positions of the helical slit cells in the two sets of cells in the circumferential direction are different by 1/4 weeks.

6. The curved tube according to claim 2, wherein the curved section comprises a first curved section and a second curved section, the clamping portion is disposed at a first end of the first curved section, a second end of the first curved section is connected to a first end of the second curved section, and the rigid section is disposed at a second end of the second curved section;

the first inter-group spacing is less than the second inter-group spacing.

7. The curved tube according to any one of claims 1 to 5, wherein the primary slit is formed between a first slit edge and a second slit edge, both extending in a circumferential direction of the curved section;

8. The curved tube according to claim 7, wherein the curved section comprises a first curved section and a second curved section, the clamping portion is disposed at a first end of the first curved section, a second end of the first curved section is connected to a first end of the second curved section, and the rigid section is disposed at a second end of the second curved section;

the first main slit interval is smaller than the second main slit interval.

9. The curved pipe according to any one of claims 1 to 5, wherein the curved section comprises a first curved section and a second curved section, the clamping portion is disposed at a first end of the first curved section, a second end of the first curved section is connected to a first end of the second curved section, and the rigid section is disposed at a second end of the second curved section;

the first subsection is provided with a spiral seam unit in the second rotary direction; the second subsection is provided with a spiral seam unit in the first rotation direction; the third subsection is provided with a spiral seam unit in the second rotation direction; and the fourth subsection is provided with the spiral seam unit in the first rotation direction.

10. The curved tube according to claim 9, wherein the first subsection is symmetrical to the second subsection with respect to a cross-section of a corresponding location of the curved section when the curved section is unbent; the third subsection and the fourth subsection are symmetrical about the cross section of the corresponding position of the bent section.

11. The bending tube according to any one of claims 1 to 5, further comprising an outer tube disposed outside at least a portion of the clamping portion, the bending section, and the hard section, wherein the outer tube comprises one or more layers of polymer material.

12. An endoscope, characterized by comprising the bending tube according to any one of claims 1 to 11.