Curved section for endoscopes

Abstract

A bending section (5) for an endoscope (1) and an endoscope are disclosed, wherein the bending section comprises a plurality of segments (12), wherein adjacent segments are connected by a first hinge (14) and a second hinge (24). Both the first hinge and the second hinge are integrally made of the same material as the segments (12), and the first hinge and the second hinge are arranged to allow the connected segments to bend in a bending plane. The second hinge at the distal end of the segment forms a continuous rib (44) with the second hinge (24) at the proximal end of the segment. This continuous rib is arranged perpendicular to the bending plane.

Description

[0001] The present invention relates to an endoscope, and in particular to a bending section for an endoscope, wherein the bending section comprises a plurality of segments, wherein adjacent segments are connected by a first hinge and a second hinge, both of which are integrally made of the same material as the segments.

[0002] Endoscopes are known for visual inspection of inaccessible places such as body cavities of the human body. Typically, an endoscope includes an insertion cord connected to an operating handle at the proximal end of the insertion cord and to a visual inspection device such as a built-in camera at the distal end of the insertion cord. Wires for the camera and other electronic devices (such as LED lighting) extend along the interior of the insertion cord from the handle to a tip at the distal end.

[0003] In order to be able to manipulate the endoscope inside the body cavity, the distal end of the endoscope may include a section with increased flexibility, such as a curved section. Typically, the curved section is controlled from the control handle by tensioning or relaxing a pull line of a control mechanism extending from the curved section along the internal insertion cord to the control handle. In addition, a working channel may extend from the handle to the tip via the curved section along the interior of the insertion cord, for example to allow removal of fluid from the body cavity or to allow insertion of surgical instruments, etc., into the body cavity.

[0004] WO 2014 / 106511 A1 discloses a curved section for an endoscope. In this curved section, adjacent segments are connected by three hinges, which are made of the same material as the segments and manufactured in the same molding process as the segments, so that the curved section is a single-piece construction. These hinges are shown to have a relatively small cross-sectional area and are measured to be relatively narrow in a direction perpendicular to the longitudinal axis of the curved section and extending in the radial direction. This configuration results in a curved section with limited torsional and longitudinal stiffness.

[0005] It is desirable to have a bending section that allows the tip of the endoscope to be manipulated to its extreme position (i.e., maximum bending) and to apply some force without risking compromising the performance of the bending section (e.g., displacement of the hinge by plastic deformation in the material). Additionally, it is desirable to maintain the performance of the bending section even when the bending section is exposed to forces in a direction perpendicular to the plane of the bend. The manipulability of the bending section and, for example, the forces on the hinge is further challenged when a tool is arranged in the working channel of the endoscope.

[0006] In view of the above, the object of the present invention is to provide a bending section of the above type with improved torsional and longitudinal stiffness. This should preferably be achieved without having to apply more force for bending. Moreover, the space available for a possible working channel should preferably not be reduced.

[0007] It has now been found that this problem can be solved by providing a bending section wherein the first and second hinges are arranged to allow the connected segments to bend in a bending plane wherein the second hinge at the distal end of the segment forms with the second hinge at the proximal end of the segment a continuous rib perpendicular to the bending plane. This improves longitudinal and torsional stiffness since the continuous rib will serve as an anchor point for the second hinge which can then be made wider than in the prior art.

[0008] Here, a bending plane is understood to be the plane in which two adjacent segments will bend. Thus, in the case of a bidirectional bending section, this bending plane will also be the overall bending plane of the bending section. There may be exactly two hinges between two adjacent segments passing through the entire bending section or for a portion of the bending section. There may be more than two hinges between two adjacent segments passing through the entire bending section or for a portion of the bending section.

[0009] In an embodiment of the bending section, a first width is defined for the first hinge in a direction perpendicular to the bending plane, and a second width is defined for the second hinge in a direction perpendicular to the bending plane, wherein the second width is at least twice as large as the first width. This provides a mechanically strong and stable bending section.

[0010] In an embodiment of the bending section, the first hinge and the second hinge are placed in mutually opposite or approximately opposite directions to the central axis of the bending section, and the first width and the second width extend in radial directions from the central axis. This has the advantage of providing a stable bending section with similar bending characteristics in both bending directions.

[0011] In other embodiments, a diameter line may be defined for the curved section. This diameter line passes through the central axis of the curved section, and the diameter line may be placed between the two segments to pass through both the first hinge and the second hinge. This diameter line is used to describe the position of the two hinges relative to the central axis of the curved section, rather than defining the measurement of the curved section diameter. The width of the first hinge and the second hinge will also be measured along this diameter line.

[0012] In an embodiment of the bending section, the bending section including the segments and the hinge has been molded as a single-piece construction. This can be made in a single piece from one material, or it can also be made in a single piece but from, for example, two materials (such as by a two-component molding process). The material used is preferably a plastic material. This provides a simpler and thus cheaper production and is particularly advantageous when the bending section is to be used with a disposable endoscope.

[0013] In an embodiment of a curved segment, the curved segment comprises a passage through each segment, the passage being adapted to accommodate a working channel of an endoscope. The passage is arranged so that it passes between the first hinge and the second hinge. This provides a symmetrical curved segment, thereby giving the same bending characteristics in both directions in the case of a bidirectional curved segment.

[0014] In an embodiment of the curved section, the width of the second hinge, referred to as the second width, is at least three times greater than the first width, preferably the second width is four times greater than the first width. It has been found that this results in an even more stable curved section.

[0015] In an embodiment of a curved segment, the second width varies with position in the longitudinal direction from the distal segment toward the proximal segment. This can be used to achieve differences in bending performance between different groups of segments. In a further embodiment, the second width of the second hinge located near the distal segment or the proximal segment is smaller than the second width of the second hinge arranged in the middle of the curved segment. This can provide some advantages in the process of molding the curved segment.

[0016] In an embodiment of a bending section, the second width of the second hinge is the same or substantially the same between all segments of the bending section. This will give the same bending performance between all segments of the bending section, thereby giving a predictable overall bending performance of the bending section.

[0017] In the embodiment of the curved section, the second hinge separates two passages suitable for arranging the wires. This leaves two well-defined spaces for the wires. Before arranging the wires in the curved section, the wires can be arranged in two bundles.

[0018] In a second aspect, the invention relates to an endoscope comprising a curved section according to any one of the above embodiments. In a further embodiment, the endoscope is suitable for single use. Single use means that the endoscope is discarded after having been used on one patient.

[0019] In a third aspect, the present invention relates to an endoscope system comprising a monitor and an endoscope according to the endoscope described above.

[0020] Embodiments of the present invention will be described in more detail hereinafter with reference to the accompanying drawings, in which:

[0021] Figure 1 A perspective view of an endoscope with a curved section is shown.

[0022] Figure 2 A perspective view of the distal end of an endoscope including a curved section is shown.

[0023] Figure 3A cross-section of a segment through a curved section is shown.

[0024] Figure 4 A side view of the curved section is shown, with the plane with the hinge perpendicular to the plane of the paper.

[0025] Figure 5 Shows a 90 degree rotation around the longitudinal axis Figure 4 Side view of the curved section.

[0026] Figure 6 A side view of a curved segment is shown, wherein the plane with the hinge is perpendicular to the plane of the paper, wherein the curved segment is different from Figure 4 The curved section in .

[0027] Figure 7 Shows a 90 degree rotation around the longitudinal axis Figure 6 Side view of the curved section.

[0028] Figure 8 Shown Figure 7 An enlarged portion of the curved section in C.

[0029] Fig. 9 Shown Figure 7 Cross-sectional view AA of the curved section.

[0030] Fig.10 Shown Figure 7 Cross-sectional view BB of the curved section.

[0031] Fig.11 A perspective view of a cut through a curved section is shown.

[0032] Fig.12 Another side view of the curved section is shown.

[0033] Fig.13 An embodiment of a curved section is shown in which the second hinge has a varying width.

[0034] Fig.14 Shown Fig.13 Further embodiments of the curved section.

[0035] Figure 1 An endoscope 1 is shown, which has a control handle 2, an insertion cord 3, and the insertion cord includes a distal end 4 and a curved section 5. Also shown is a diagram for displaying the endoscope through a camera 8 (see Figure 2) is a monitor 30 for viewing the image seen by the endoscope. The monitor may be connected to the handle 2 by a cable 31. Here, the control handle 2 is provided with a control lever, which enables the operator of the endoscope 1 to control the bending of the bending section 5 by, for example, two pull wires, which can be tightened or loosened to allow the bending section to bend in one plane but in two opposite directions. The bending of the bending section can alternatively be controlled by one or more steering wires that can be alternately pulled and pushed, whereby one steering wire can bend the bending section in two directions.

[0036] Figure 2 A closer view of the distal end 4 is shown, which has a curved section 5 and a distal tip 7. Here, in order to clearly show the curved section, the curved cover portion that usually protects the curved section is not shown. Figure 2 The distal tip 7 includes a camera 8, a light emitting diode 9 and an opening or passage 10 for a working channel. The working channel can be used for flushing or removing liquids, or for introducing tools (e.g., for sample collection).

[0037] The bending section 5 consists of a plurality of sections, including a distal segment 11 forming part of the distal tip 7 and a proximal segment 13 connected to the rest of the insertion cord 3. In addition, a plurality of segments 12 are arranged between the distal segment 11 and the proximal segment 13. The segments 11, 12, 13 are interconnected by hinges 14. These hinges 14 are preferably made integrally of the same material as the segments 12, and preferably the hinges and the segments 11, 12, 13 form a single continuous piece of material. Examples of materials may be polypropylene, polyacetal (POM) or semi-aromatic polyamide (nylon).

[0038] Figure 2 It is further shown that the working channel 10, also seen at the distal tip, continues all the way through the curved section 5. The working channel 10 comprises a conduit arranged in the passage 33 (see Figure 3 and Figure 4 ) in order to form a working channel that is sealed against liquids, etc.

[0039] Figure 2 Also indicated are holes 15 for positioning pull wires (pull wires not shown). The pull wires are arranged inside the guide tube so as to form a Bowden cable along the distance from the control handle 2 to the proximal segment 13 of the bending section. The guide tube terminates at the proximal segment 13 and the pull wires continue through holes 15 in the bending section. These holes 15 form guide channels for the pull wires and are preferably placed close to the outer periphery of the bending section. The pull wires are fastened to the distal segment 11 or are fastened in the distal end 7. This configuration, together with the hinge 14, allows the bending section to be bent by tensioning one pull wire and relaxing the other pull wire.

[0040] Figure 3 A cross-sectional view of the curved section is shown ( Figure 2 A'-A' in ). The longitudinal center axis is indicated by a cross 17. A passage 10 for the working channel is also shown. This passage will generally have a circular shape. The holes 15 for the pull wires can also be seen. These holes are generally arranged in the opposite direction to the longitudinal center axis 17 and will extend parallel to this axis. In the top of the passage 10, a first hinge 14 is arranged between the segments 12.

[0041] exist Figure 3 2 shows two further passages 18, 19 in cross-section. These passages 18, 19 are suitable for accommodating, for example, wires for transmitting power and signals between the control handle 2 and the camera, lighting device and electronic equipment in the distal tip 4. The two passages are separated by a hinge 24, which is called a second hinge. This second hinge 24 will form a connection between the segments. The second hinge 24 at the distal end of the segment 12 forms a continuous rib 44 (such as Fig.10 1 ), wherein a second hinge at the proximal end of the segment at least partially provides a reinforcing partition between passages 18, 19, thereby increasing the overall strength of the curved segment 5. This continuous rib 44 is arranged in a plane perpendicular to the plane of the bend. The first hinge 14 and the second hinge 24 may be the only connection between adjacent segments 12 of the curved section. However, some embodiments may include more than two hinges between adjacent segments. Examples of such embodiments are shown in Fig.13 Shown in.

[0042] The continuous rib 44 is preferably formed as a sheet of material which also forms the second hinge 24. The continuous rib will extend in a plane perpendicular or substantially perpendicular to the bending plane. Thus, this continuous rib 44 is adjacent to the second hinge 24 and will preferably continue through several sections 12 of the bending section 5 when the rib 44 forms the second hinge 24 and when the rib 44 forms the connection of two second hinges through the sections 12 of the bending section and will have the same or substantially the same thickness. The rib separates two passages 18, 19 which are formed in each section 12 and continue through the entire bending section 5. Thus, the rib can be described as a continuous sheet extending through several bending section sections 12 and forming the second hinge 24 between these sections.

[0043] Typically, the first hinge 14 and the second hinge 24 together form a hinge plane that can pass through the central axis 17. The holes 15 for the pull wires passing through these segments extend along two lines ( Figure 215. One such line 32 is shown in FIG. 15. When the bending section is in the non-bending (i.e. neutral) position, the two lines of holes 15 extend in the longitudinal direction of the bending section. The two lines of holes will form a pull-wire plane, which may also pass through the central axis 17. The pull-wire plane will also be the plane in which the bending section bends when the pull wire is manipulated. Typically, the hinge plane will extend perpendicular to the pull-wire plane, while the pull-wire plane will be parallel to or coincide with the bending plane.

[0044] Figure 4 A side view of the curved section is shown, wherein the plane with the hinge is perpendicular to the plane of the paper. That is, both hinges 14 , 24 are considered to be placed in the centerline of the curved section and are the only connection between the segments 12 . Figure 4 Further shown are a plurality of wedge-shaped spaces 21, 22 between the segments 12. These wedge-shaped spaces 21, 22 will allow the bending segment to bend. When the bending segment is in a neutral (straight) position, as Figure 4 As shown, the angle of the wedge-shaped space is indicated as v. As the bending segment bends, the angle v becomes smaller on one side and larger on the opposite side. The angle v and the total number of segments determine the overall bending performance of the bending segment (including the maximum bending angle and bending radius).

[0045] The number of segments in a curved section may be, for example, in the range of 10-24, such as in the range of 12-20. For clarity, a smaller number of segments are shown in the figures. The bending radius of the curved section is typically in the range of 8 mm to 17 mm (measured about the central axis of the curved section). Preferably, the bending radius will typically be in the range of 10 mm to 15 mm.

[0046] Figure 4 The curved double arrow 30 at the bottom indicates when Figure 4 The bending direction of the bending section shown when it bends. Figure 4 The height h of the hinge is also indicated in FIG. The height h may be the same for all hinges in the curved section, and the height may then be in the range of, for example, 0.2 mm to 0.5 mm. Figure 4 As indicated, the height may also increase when moving from the distal end towards the proximal end of the curved section, as also proposed in WO 2014 / 106511 A1. However, the hinge between two specific segments will preferably have the same height h.

[0047] Figure 5 shows a 90 degree rotation about the longitudinal axis Figure 4 The curved section 5 is shown here with hinges 14, 24 between the segments 12. A passage 33 for the working channel is also indicated. Figure 5 When the bending section shown bends, the motion will be in a plane perpendicular to the plane of the paper.

[0048] Figure 5 An example of a diameter line 35 defined for a curved section is shown. The diameter line passes through the central axis 17 of the curved section (this is from Figure 5 The diameter line 35 is used to describe the position of the two hinges relative to the central axis of the curved section, rather than to define the measurement of the diameter of the curved section. The width of the first hinge and the second hinge can also be measured along this diameter line.

[0049] from Figure 5 It is clear from the figure that the width of the second hinge 24 (i.e., the second width) is significantly greater than the width of the first hinge 14 (i.e., the first width). Preferably, the width of the second hinge 24 is at least twice as large as the width of the first hinge 14. The second width may be at least three times as large as the first width, and the second width may even be at least four times as large as the first width. In addition, the second width is at least 10%, such as at least 15%, or even at least 20% of the outer diameter of the curved segment.

[0050] In this way, the larger width of the second hinge increases the stability of the hinge, since the stronger second hinge reduces the risk of displacement of either the first hinge or the second hinge. Thus, by introducing a larger second hinge, the risk of the relatively narrow first hinge being displaced or even broken is also reduced. Even in the event of displacement or breakage of the first hinge, the correspondingly larger second hinge will be able to maintain much greater stability and functionality in the connection between two adjacent segments compared to the curved sections of the prior art.

[0051] Figures 6 to 10 Different examples of curved sections are shown, where Figure 6 A side view of the curved section is shown, where the plane with the hinge is perpendicular to the plane of the paper. Here, the angle v is less than Figure 4 Furthermore, the height h of the hinge is shown to be the same for all hinges of the curved section, which is different from Figure 4 . Figure 7 Shows a 90 degree rotation around the longitudinal axis Figure 6 Side view of the curved section. Figure 7 , two cross-sectional cuts AA and BB are indicated. Figure 7 The curved section C in the Figure 8 is enlarged and shown.

[0052] and Figure 7 In comparison, Figure 8The first hinge 14 and the second hinge 24 can be seen more clearly in FIG. It is also shown that the segments 12 are provided with inclined edges 37 towards the space between the segments. Fig. 9 Shown Figure 7 The cross-section AA between the two segments 12 of the curved section in FIG. The cross-section AA only passes through the first hinge 14 and the second hinge 24 as shown by hatching. Fig.10 Shown Figure 7 BB in the middle of the segment 12 of the curved section in FIG. The hatching shows that the section BB passes through both the segment 12 and the continuous rib 44. This continuous rib 44 is formed between the second hinge 24 at the distal end of the segment 12 and the second hinge 24 at the proximal end of the segment.

[0053] Fig.11 A perspective view of a cut through the curved section is shown, illustrating the first hinge 14 and the second hinge 24 as well as the passage 10 for the working channel and the hole 15 for the pull wire.

[0054] Preferably, the second hinge 24 will separate the two passages 18, 19 along the entire curved section and between all segments 12 of the curved section. This will provide the strongest curved section with the least risk of the hinge being dislodged.

[0055] The second width of the second hinge may be constant or approximately constant throughout the entire curved section or a majority of the curved section. Fig.12 A side view of a curved section is shown, wherein the second width of the second hinges 24 is the same for the second hinges shown.

[0056] In an alternative embodiment, the second hinge 24 only completely separates the two passages 18, 19 for the segment to be arranged in the middle of the curved section, while there will be an opening through the second hinge between the two passages 18, 19 towards at least one end of the curved section and preferably towards both the distal and proximal ends of the curved section. This opening will actually mean that the second hinge is divided into two separate hinges towards the ends of the curved section. One advantage of this embodiment relates to the manufacture, i.e. molding, of the curved section.

[0057] Fig.13 A portion of a curved section 5 according to this embodiment is shown in FIG. 5 , which shows the curved section in a side view. Fig.13 , the second width of the second hinge increases from left to right in the figure. Fig.13 The second hinge on the left side in the drawing has a smaller width, but this leaves room for a third hinge between the first hinge 14 and the second hinge 24.

[0058] Fig.14A further embodiment is shown which does not have a third hinge, but in which the second hinge has a variable width. This variable width may mean that the continuous rib is limited by the outer diameter of the curved section and a line or curve that is not parallel to the central axis of the curved section. The continuous rib will still extend in a plane perpendicular to the curved plane.

Claims

1. A bending section for an endoscope, the bending section comprising a plurality of segments, wherein adjacent segments are connected by a first hinge and a second hinge, both of which are integrally made of the same material as the segments, the first hinge and the second hinge being arranged to allow the connected segments to bend in a bending plane, wherein the second hinge at the distal end of the segment forms a continuous rib perpendicular to the bending plane with the second hinge at the proximal end of the segment to separate two passages, the two passages being formed in each segment and continuing through the entire bending section.

2. The curved section according to claim 1, wherein: A first width is defined for the first hinge in a direction perpendicular to the bending plane, and a second width is defined for the second hinge in a direction perpendicular to the bending plane, wherein the second width is at least twice as large as the first width.

3. The curved section according to claim 2, wherein: The first hinge and the second hinge are placed in opposite or approximately opposite directions to each other with respect to a central axis of the curved section, and the first width and the second width extend in a radial direction from the central axis.

4. The curved section according to claim 3, wherein: A diameter line is defined for the curved section, the diameter line passing through the central axis of the curved section, and the diameter line can be placed between the two segments to pass through both the first hinge and the second hinge.

5. The curved section according to claim 1, wherein: The curved section including the segments and hinges is molded as a one-piece construction.

6. A curved segment according to claim 1 or 2, comprising a passage through each segment, the passage being adapted to accommodate a working channel of the endoscope, the passage being arranged so that the passage passes between the first hinge and the second hinge.

7. The curved section according to claim 2, wherein: The second width is at least three times greater than the first width.

8. The curved section according to claim 2, wherein: The second width varies with position in a longitudinal direction from a distal segment of the plurality of segments toward a proximal segment of the plurality of segments.

9. The curved section according to claim 8, wherein: The second width of the second hinge located near the distal segment or the proximal segment is smaller than the second width of the second hinge arranged between segments in the middle of the curved section.

10. The curved section according to claim 8, wherein: A third hinge is arranged between at least some of the segments, and the third hinge is arranged between the first hinge and the second hinge.

11. The curved section according to any one of claims 1 to 5, wherein: The second width of the second hinge is the same between all segments of the curved section.

12. The curved section according to claim 1, wherein: The second hinge separates two passages suitable for routing electrical wires.

13. An endoscope comprising a curved section according to any one of the preceding claims.

14. An endoscope system comprising a monitor and the endoscope according to claim 13.

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