Endoscope shaft

Abstract

To provide an endoscope shaft excellent in multidirectional plasticity.SOLUTION: An endoscope shaft has a first cylindrical part having an axial direction, a second cylindrical part adjacent in the axial direction to the first cylindrical part, and at least one first connection part extending in an inclination direction inclined to the axial direction of the first cylindrical part, and connected to the first cylindrical part and the second cylindrical part.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an endoscope shaft.

Background Art

[0002] In the medical field, movable endoscopes are used, and the shafts of movable endoscopes often have a structure formed by connecting a plurality of round tubular segments. For example, Patent Document 1 discloses an endoscope in which a controllable bending tube is provided in the insertion portion of the endoscope, and the controllable bending tube includes a plurality of round tubular segments connected in series to each other and a control device for controlling the bending of the controllable bending tube.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Patent Document 1 describes that a spherical protrusion provided on a round tubular segment is fitted into a C-shaped notch provided on another round tubular segment so that the other round tubular segment can move relatively. In the shaft of an endoscope having such round tubular segments, the shaft can be bent in a desired two-dimensional direction by pulling a wire fixed to the round tubular segment. Therefore, it is considered that the shaft has flexibility in a desired two-dimensional bending direction, but does not have flexibility in other directions. The present invention has been made by paying attention to the above problems, and an object thereof is to provide an endoscope shaft excellent in flexibility in multiple directions.

Means for Solving the Problems

[0005] The shaft of the endoscope according to an embodiment of the present invention that can solve the above problems is as follows. [1] The shaft of an endoscope, A first cylindrical portion having an axial direction, The first cylindrical portion and the second cylindrical portion adjacent to it in the axial direction, The shaft of an endoscope having at least one first connecting portion that extends in an inclined direction inclined with respect to the axial direction of the first cylindrical portion and is connected to the first cylindrical portion and the second cylindrical portion.

[0006] Because the first connecting portion extends in an inclined direction relative to the axial direction of the first cylindrical portion, the first connecting portion can be extended so that its extending direction approaches parallel to the axial direction of the first cylindrical portion, while also being compressed so that it approaches perpendicular. This allows, for example, the second cylindrical portion to bend in multiple directions in three dimensions relative to the first cylindrical portion. As a result, when inserting the shaft into body tissue, the shaft can exhibit flexibility in multiple directions and bend appropriately to conform to the shape of the body tissue, making it easier to insert the shaft into body tissue.

[0007] The shaft of the endoscope according to the embodiment is preferably one of the following [2] to

[15] . [2] The shaft of the endoscope according to [1], wherein the inclination direction is the direction in which the shaft is inclined with respect to the axial direction in a first side view of the shaft, when the shaft is oriented in a direction in which the width of the first joint at the center point of the first joint is maximized. [3] The shaft of the endoscope according to [1] or [2], wherein, in a second side view of the shaft when the shaft in the first side view is rotated 90 degrees in the circumferential direction, the angle between a virtual straight line passing through the end of the first joint on the first cylindrical part side and the end of the first joint on the second cylindrical part side and the radial direction of the first cylindrical part is 70 degrees or more and 110 degrees or less. [4] The shaft of the endoscope according to any one of [1] to [3] further having at least one second connecting portion that extends in parallel with the at least one first connecting portion and is connected to the first cylindrical portion and the second cylindrical portion. [5] The shaft of the endoscope according to [4], wherein the at least one first connecting portion and the at least one second connecting portion each have a widened portion that is wider toward the second cylindrical portion. [6] The shaft of an endoscope according to [4] or [5], wherein the at least one first connecting portion and the at least one second connecting portion each have a narrowed portion that is narrower toward the second cylindrical portion. [7] The shaft of the endoscope described in [6], wherein the narrowed portion is located closer to the second cylindrical portion than the widened portion and is adjacent to the widened portion. [8] The shaft of an endoscope according to any one of [5] to [7], wherein the outer edge of the widened portion has a curved portion. [9] The shaft of an endoscope according to any one of [6] to [8], wherein the outer edge of the narrowed portion has a curved portion.

[10] The shaft of an endoscope according to any one of [1] to [9], wherein the at least one first coupling portion has a one-side coupling portion located on one side of the radial direction of the first cylindrical portion and a other-side coupling portion located on the other side.

[11] The shaft of the endoscope according to

[10] , wherein the other coupling portion is opposite to the one coupling portion in the radial direction.

[12] The shaft of an endoscope according to any one of [4] to

[11] , wherein the at least one second coupling portion has a one-side coupling portion located on one side of the radial direction of the first cylindrical portion and a other-side coupling portion located on the other side.

[13] The shaft of the endoscope according to

[12] , wherein the other coupling portion is opposite to the one coupling portion in the radial direction.

[14] The shaft of an endoscope according to any one of [1] to

[13] , wherein the first cylindrical portion is divided into a first region and a second region of the first cylindrical portion, which are defined by a first virtual plane that includes the central axis of the shaft and extends along the central axis, and which forms a line when the shaft is oriented in a direction in which the width of the first joint at the center point of the first joint is maximized, the first region having a first lumen extending in the axial direction, and the second region having a second lumen extending in the axial direction.

[15] The shaft of an endoscope according to any one of [1] to

[14] , wherein the first cylindrical portion has a tapered portion that narrows toward the radially outward direction. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an endoscope shaft with excellent flexibility in multiple directions. Specifically, it is possible to provide an endoscope shaft with excellent flexibility in at least a first direction, a second direction opposite to the first direction, a third direction toward one side of a direction perpendicular to a virtual plane including the first and second directions, and a fourth direction toward the other side opposite to the third direction. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a front view of the shaft of an endoscope according to an embodiment. [Figure 2] Figure 2 is a side view of the internal structure of the shaft as seen from direction A in Figure 1. [Figure 3] Figure 3 is a side view of the internal structure shown in Figure 2 when it is bent in the first direction. [Figure 4] Figure 4 is a side view of the internal structure shown in Figure 2 when it is bent in the second direction. [Figure 5] Figure 5 is a side view of the internal structure shown in Figure 2 when it is bent in a third direction. [Figure 6] Figure 6 is a side view of the internal structure as seen from direction D in Figure 2. [Figure 7] Figure 7 is a magnified view of a portion of the internal structure shown in Figure 2. [Figure 8] FIG. 8 is a partially enlarged view of a modification of the internal structure of FIG. 2. [Figure 9] FIG. 9 is a partially enlarged view of a modification of the internal structure of FIG. 2. [Figure 10] FIG. 10 is a side view of the internal structure of the shaft when viewed from the B direction of FIG. 1. [Figure 11] FIG. 11 is a cross-sectional view of the A-A cross-section of FIG. 2. [Figure 12] FIG. 12 is a side view of the internal structure of the shaft when viewed from the C direction of FIG. 2. [Figure 13] FIG. 13 is a side view of a modification of the internal structure of FIG. 2.

MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, the present invention will be described more specifically based on the following embodiments. However, the present invention is not limited by the following embodiments, and it is of course possible to appropriately modify and implement within the range that can conform to the gist of the foregoing and following descriptions, and all of them are included in the technical scope of the present invention. In each drawing, for convenience, component reference numerals and the like may be omitted, but in such a case, reference shall be made to the specification and other drawings. In addition, the dimensions of various members in the drawings may differ from the actual dimensions because priority is given to facilitating understanding of the features of the present invention.

[0011] The shaft of the endoscope according to the embodiment is a shaft of an endoscope, and has a first cylindrical portion having an axial direction, a second cylindrical portion axially adjacent to the first cylindrical portion, and at least one first coupling portion extending in an inclined direction inclined with respect to the axial direction of the first cylindrical portion and coupling the first cylindrical portion and the second cylindrical portion.

[0012] Because the first connecting portion extends in an inclined direction relative to the axial direction of the first cylindrical portion, the first connecting portion can be extended so that its extending direction approaches parallel to the axial direction of the first cylindrical portion, while also being compressed so that it approaches perpendicular. This allows, for example, the second cylindrical portion to bend in multiple directions in three dimensions relative to the first cylindrical portion. As a result, when inserting the shaft into body tissue, the shaft can exhibit flexibility in multiple directions and bend appropriately to conform to the shape of the body tissue, making it easier to insert the shaft into body tissue.

[0013] The shaft of the endoscope according to the embodiment will be described below with reference to Figures 1 to 13. Figure 1 is a front view of the shaft of the endoscope according to the embodiment. Figure 2 is a side view of the internal structure of the shaft as seen from direction A in Figure 1. Figures 3, 4, and 5 are side views of the internal structure of Figure 2 when bent in the first, second, and third directions, respectively. Figure 6 is a side view of the internal structure as seen from direction D in Figure 2. Figure 7 is a partially enlarged view of the internal structure of Figure 2. Figures 8 and 9 are partially enlarged views of modified versions of the internal structure of Figure 2. Figure 10 is a side view of the internal structure of the shaft as seen from direction B in Figure 1. Figure 11 is a cross-sectional view of the AA section in Figure 2. Figure 12 is a side view of the internal structure of the shaft as seen from direction C in Figure 2. Figure 13 is a side view of a modified version of the internal structure of Figure 2. In Figures 7 to 9, the description of the preferably used operating wire is omitted. Also, in Figures 2 to 13, the description of the preferably used cable is omitted.

[0014] As shown in Figure 1, the shaft according to the embodiment is the shaft 31 of the endoscope 30, and as shown in Figure 2, it has a first cylindrical portion 1 having an axial direction X, a second cylindrical portion 2 adjacent to the first cylindrical portion 1 in the axial direction X, and at least one first connecting portion 10 that extends in an inclined direction W that is inclined with respect to the axial direction X of the first cylindrical portion 1 and connects the first cylindrical portion 1 and the second cylindrical portion 2.

[0015] As shown in Figure 2, the first connecting portion 10 extends in an inclined direction W that is inclined with respect to the axial direction X of the first cylindrical portion 1. As shown in Figure 3, by pulling in the first direction and stretching the first connecting portion 10 so that its extending direction and the axial direction X of the first cylindrical portion 1 become nearly parallel, the second cylindrical portion 2 can be bent in the first direction relative to the first cylindrical portion 1. Furthermore, as shown in Figure 4, by pulling in the second direction and compressing the first connecting portion 10 so that its extending direction and the axial direction X of the first cylindrical portion 1 become nearly perpendicular, the second cylindrical portion 2 can be bent in the second direction relative to the first cylindrical portion 1. The second direction is the direction opposite to the first direction.

[0016] Furthermore, as shown in Figure 5, by extending the first connecting portion 10 so that its extension direction and the axial direction X of the first cylindrical portion 1 become nearly parallel, the second cylindrical portion 2 can be bent in a third direction relative to the first cylindrical portion 1. The third direction is one of the directions perpendicular to the virtual plane that includes the first and second directions, and in Figure 5, it is the direction from front to back. Furthermore, although not shown, by compressing the first connecting portion 10 so that its extension direction and the axial direction X of the first cylindrical portion 1 become nearly perpendicular, the second cylindrical portion 2 can be bent in a fourth direction relative to the first cylindrical portion 1. The fourth direction is the opposite direction to the third direction, and in Figure 5, it is the direction from back to front.

[0017] This first connecting portion 10 allows, for example, the second cylindrical portion 2 to bend three-dimensionally in multiple directions relative to the first cylindrical portion 1. As a result, when inserting the shaft 31 into body tissue, the shaft 31 can exhibit flexibility in multiple directions and bend appropriately to conform to the shape of the body tissue, making it easier to insert the shaft 31 into body tissue.

[0018] Furthermore, since the first connecting portion 10 is connected to the first cylindrical portion 1 and the second cylindrical portion 2, and these are formed as a single unit, the second cylindrical portion 2 can easily return to its original position after being bent relative to the first cylindrical portion 1. As a result, the shaft 31 can easily return to its original straight shape after being bent. For this reason, it is preferable that the first cylindrical portion 1, the first connecting portion 10, and the second cylindrical portion 2 are formed as a single unit without any joints.

[0019] If the shaft 31 has multiple repeating units of cylindrical sections and connecting sections in the axial direction, a curved shape can be formed by continuously bending multiple cylindrical sections in the same direction, as shown in Figures 3 and 4. This expands the observable range of the endoscope 30.

[0020] As shown in Figure 2, the inclination direction W is preferably the direction of inclination with respect to the axial direction X in a first side view of the shaft 31, when the shaft 31 is oriented in a direction that maximizes the width of the first joint 10 at the center point 10c of the first joint 10. The angle between the inclination direction W of the first joint 10 and the axial direction X when the shaft 31 is not bent is preferably 10 degrees or more, more preferably 30 degrees or more, even more preferably 40 degrees or more, preferably 80 degrees or less, more preferably 60 degrees or less, and even more preferably 50 degrees or less. This makes the first joint 10 easier to extend and compress. Note that this angle is the inclination angle of the inclination direction W with respect to the axial direction X. For example, in Figure 2, the first joint 10 is inclined at approximately 45 degrees with respect to the axial direction X so that it extends downwards as it approaches the second cylindrical part 2, but it may also be inclined at approximately 45 degrees with respect to the axial direction X so that it extends upwards as it approaches the second cylindrical part 2.

[0021] As shown in Figure 6, in the second side view of the shaft 31 when the shaft 31 in the first side view of Figure 2 is rotated 90 degrees in the circumferential direction, it is preferable that the angle between the imaginary straight line L passing through the end 10a on the first cylindrical part side of the first connecting part 10 and the end 10b on the second cylindrical part side of the first connecting part 10 and the radial direction Y of the first cylindrical part 1 is 70 degrees or more and 110 degrees or less. This makes it easier to push the shaft 31 in the axial direction X. More preferably, this angle is 75 degrees or more and 105 degrees or less. This angle is the inclination angle of the imaginary straight line L with respect to the radial direction Y. For example, in Figure 6, the first connecting part 10 is inclined at approximately 80 degrees with respect to the radial direction Y so that it extends downwards as it approaches the second cylindrical part 2, but it may also be inclined at approximately 80 degrees with respect to the radial direction Y so that it extends upwards as it approaches the second cylindrical part 2.

[0022] In this specification, radial direction Y refers to the radial direction of the first cylindrical portion 1 in a second side view of the shaft 31. Specifically, radial direction Y refers to the vertical direction of the first cylindrical portion 1 in Figure 6.

[0023] As shown in Figure 6, the thickness of the first joint 10 in the radial direction Y is preferably smaller than the radius of the first cylindrical part 1. This makes it easier to bend the second cylindrical part 2 in multiple directions relative to the first cylindrical part 1. Specifically, the thickness is preferably less than 0.50 times the outer diameter of the first cylindrical part 1, more preferably 0.30 times or less, and even more preferably 0.20 times or less. On the other hand, the thickness is preferably 0.05 times or more the outer diameter of the first cylindrical part 1, more preferably 0.10 times or more, and even more preferably 0.15 times or more. This makes it easier for the second cylindrical part 2 to return to its original position after being bent relative to the first cylindrical part 1. The outer diameter of the first cylindrical part 1 refers to the diameter of the circle when the outer edge of the radial cross-section of the first cylindrical part 1 is circular, and to the diameter of the circumscribed circle of the outer edge of the first cylindrical part 1 when it has any other shape. The radial cross-sectional shape of the first cylindrical portion 1 is preferably circular, elliptical, or a rounded polygon, and more preferably circular or elliptical. Examples of rounded polygons include a rounded triangle, a rounded quadrilateral, a rounded pentagon, or a rounded hexagon.

[0024] As shown in Figure 2, it is preferable that the shaft 31 further has at least one second joint 20 that extends in parallel with at least one first joint 10 and connects the first cylindrical portion 1 and the second cylindrical portion 2. This allows the force applied during bending to be distributed between the first joint 10 and the second joint 20, making the joint less likely to break during bending. It is also preferable that the first cylindrical portion 1, the first joint 10, the second joint 20, and the second cylindrical portion 2 are formed integrally without any joints. This makes it easier for the second cylindrical portion 2 to return to its original position after bending relative to the first cylindrical portion 1.

[0025] As shown in Figure 2, it is preferable that the second connecting portion 20 extends in the inclined direction W, which is the extending direction of the first cylindrical portion 1. This makes it easier to bend the second cylindrical portion 2 in multiple directions relative to the first cylindrical portion 1.

[0026] As shown in Figure 2, it is preferable that the first joint 10 and the second joint 20 do not come into direct contact with each other when the second cylindrical portion 2 is not bent relative to the first cylindrical portion 1. This makes it easier to compress or extend the first joint 10 and the second joint 20. Furthermore, it is even more preferable that the first joint 10 and the second joint 20 do not come into direct contact with each other even when the second cylindrical portion 2 is bent relative to the first cylindrical portion 1. This improves flexibility.

[0027] As shown in Figure 2, the outline of the hole surrounded by the first connecting portion 10, the second connecting portion 20, the first cylindrical portion 1, and the second cylindrical portion 2 is preferably elliptical, circular, or a polygon with at least one curved side, and more preferably elliptical or a polygon with at least one curved side. The polygon with at least one curved side is preferably one in which two opposing sides are curved in the inclination direction W. Examples of polygons include triangles, quadrilaterals, pentagons, or hexagons. Furthermore, it is preferable that at least one corner of the polygon is rounded. By curving a portion of the hole's outline in this way, the durability of each part near the hole is improved.

[0028] As shown in Figure 7, it is preferable that the first joint 10 and the second joint 20 have portions that are symmetrical with respect to each other. The portion that is symmetrical with respect to.

[0029] As shown in Figure 7, it is preferable that at least one first joint 10 and at least one second joint 20 each have widened portions 10d and 20d, respectively, which widen towards the second cylindrical portion 2. The widened portions 10d and 20d are flexible because their base ends are narrow, making it easy to extend and compress the first joint 10 and second joint 20, while their wide tips provide rigidity, making it easy to return the extended or compressed first joint 10 and second joint 20 to their original shape. It is also possible that one of the first joint 10 and the second joint 20 has a widened portion while the other does not.

[0030] As shown in Figure 7, it is preferable that the outer edges of the widened portions 10d and 20d have curved portions 10e and 20e. The curved portions 10e and 20e make it easier to distribute the force applied to the first joint portion 10 and the second joint portion 20 when bending, thus making the joints less likely to break when bending. Specifically, it is preferable that the curved portion 10e curves toward the side furthest from the second joint portion 20. On the other hand, it is preferable that the curved portion 20e curves toward the side furthest from the first joint portion 10. Note that one of the widened portions 10d and 20d may have a curved portion, while the other does not.

[0031] As shown in Figure 7, it is preferable that the outer edge of the widened portion 10d has a curved portion 10e on the side farther from the second joint portion 20 and a straight portion on the side closer to the second joint portion 20. On the other hand, it is preferable that the outer edge of the widened portion 20d has a curved portion 20e on the side farther from the first joint portion 10 and a straight portion on the side closer to the second joint portion 20. This allows the second cylindrical portion 2 to bend smoothly relative to the first cylindrical portion 1, and makes it easier to return the first joint portion 10 and the second joint portion 20 to their original shapes.

[0032] As shown in Figure 7, it is preferable that at least one first joint 10 and at least one second joint 20 each have a narrowed width portion 10f, 20f, which narrows in width towards the second cylindrical portion 2. The narrowed width portions 10f, 20f exhibit rigidity because their base ends are wide, making it easy to return the stretched or compressed first joint 10 and second joint 20 to their original shape, while their narrow tip ends exhibit flexibility, making it easy to stretch or compress the first joint 10 and second joint 20. Note that one of the first joint 10 and the second joint 20 may have a narrowed width portion while the other does not.

[0033] As shown in Figure 7, it is preferable that the outer edges of the narrowed width sections 10f and 20f have curved sections 10g and 20g. The curved sections 10g and 20g make it easier to distribute the force applied to the first joint section 10 and the second joint section 20 when bending, thus making the joints less likely to break when bending. Specifically, it is preferable that the curved section 10g curves toward the side furthest from the second joint section 20. On the other hand, it is preferable that the curved section 20g curves toward the side furthest from the first joint section 10. Note that one of the narrowed width sections 10f and 20f may have a curved section, while the other does not.

[0034] As shown in Figure 7, it is preferable that the outer edge of the reduced width portion 10f has a curved portion 10g on the side farther from the second joint portion 20 and a straight portion on the side closer to the second joint portion 20. On the other hand, it is preferable that the outer edge of the reduced width portion 20f has a curved portion 20g on the side farther from the first joint portion 10 and a straight portion on the side closer to the second joint portion 20. This allows the second cylindrical portion 2 to bend smoothly relative to the first cylindrical portion 1, and makes it easier to return the first joint portion 10 and the second joint portion 20 to their original shapes.

[0035] As shown in Figure 7, it is preferable that the narrowed sections 10f and 20f are located closer to the second cylindrical section 2 than the widened sections 10d and 20d, and are adjacent to the widened sections 10d and 20d. This allows the flexibility of the ends of the first joint section 10 and the second joint section 20 to allow the second cylindrical section 2 to bend smoothly relative to the first cylindrical section 1, and the rigidity of the central parts of the first joint section 10 and the second joint section 20 makes it easier for them to return to their original shape after bending.

[0036] On the other hand, as shown in Figure 8, the widening sections 10d and 20d are located closer to the second cylindrical section 2 than the narrowing sections 10f and 20f, and may be adjacent to the narrowing sections 10f and 20f. In this case, the flexibility of the central parts of the first joint section 10 and the second joint section 20 is utilized, resulting in the first joint section 10 and the second joint section 20 becoming moderately easy to twist, and improving their flexibility in the twisting direction.

[0037] In this case, as shown in Figure 8, it is preferable that the outer edge of the reduced width portion 10f has a curved portion 10g that curves toward the side farther from the second joint portion 20 on both the side farther from the second joint portion 20 and the side closer to the second joint portion 20. Furthermore, it is preferable that the outer edge of the reduced width portion 20f has a curved portion 20g that curves toward the side farther from the first joint portion 10 on both the side farther from the first joint portion 10 and the side closer to the first joint portion 10.

[0038] In this case, as shown in Figure 8, it is preferable that the outer edge of the widened portion 10d has a curved portion 10e that curves toward the side farther from the second joint portion 20 on both the side farther from the second joint portion 20 and the side closer to the second joint portion 20. Furthermore, it is preferable that the outer edge of the widened portion 20d has a curved portion 20e that curves toward the side farther from the first joint portion 10 on both the side farther from the first joint portion 10 and the side closer to the first joint portion 10.

[0039] As shown in Figures 7 and 8, it is preferable that the widening portion 10d and the narrowing portion 10f are formed integrally without any joints. Furthermore, it is preferable that the widening portion 20d and the widening portion 20f are formed integrally without any joints. This improves the strength of the first joint portion 10 and the second joint portion 20.

[0040] As shown in Figure 9, the shaft 31 may have a first joint 10 but not a second joint 20. In this case, it is preferable that the first joint 10 has a widening portion 10d and a narrowing portion 10f adjacent to the widening portion 10d. It is preferable that the widening portion 10d has curved portions 10e that curve outward on both sides in the width direction, and the narrowing portion 10f has curved portions 10g that curve outward on both sides in the width direction. This can improve the strength of the first joint 10.

[0041] As shown in Figure 11, the cross-sectional shapes of the first joint 10 and the second joint 20 in the radial cross-section of the shaft 31 are preferably polygonal. This makes it easier for the first joint 10 and the second joint 20 to return to their original shape after being stretched or compressed. The polygon is preferably a triangle, quadrilateral, pentagon, or hexagon, with a quadrilateral being more preferable. It is preferable that at least one side of the polygon is curved. It is even more preferable that two opposing sides of the polygon in the radial direction of the shaft 31 are curved. Furthermore, at least one corner of the polygon may be rounded.

[0042] As shown in Figures 6 and 11, it is preferable that at least one first connecting portion 10 has a one-side connecting portion 11 located on one of the two sides of the first cylindrical portion 1 in the radial direction Y, and a other-side connecting portion 12 located on the other side. This makes it easier to push the shaft 31 in the axial direction X. In Figure 11, one side of the first cylindrical portion 1 in the radial direction Y is perpendicular to the first virtual plane V1 (described later) and corresponds to the side above the second virtual plane V2 which contains the central axis of the shaft 31, while the other side of the first cylindrical portion 1 in the radial direction Y corresponds to the side below the second virtual plane V2.

[0043] As shown in Figure 11, it is preferable that the other side coupling portion 12 faces the one side coupling portion 11 in the radial direction Y. This makes it easier to push the shaft 31 in the axial direction X.

[0044] As shown in Figures 2, 10, and 11, it is preferable that the one-sided joint 11 and the other-sided joint 12 are perpendicular to the first virtual plane V1 (described later) and symmetrical with respect to the second virtual plane V2, which contains the central axis of the shaft 31. This makes it easier to bend the second cylindrical portion 2 in a vertical direction Z perpendicular to the first virtual plane V1 relative to the first cylindrical portion 1, using the one-sided joint 11 and the other-sided joint 12 as axes. Furthermore, it is preferable that the one-sided joint 11 and the other-sided joint 12 have the same shape, but they may have different shapes or be similar in shape.

[0045] As shown in Figures 2, 10, and 11, it is preferable that at least one second connecting portion 20 has a one-side connecting portion 21 located on one of the two radial Y sides of the first cylindrical portion 1, and a other-side connecting portion 22 located on the other side. This makes it easier to push the shaft 31 in the axial direction X.

[0046] As shown in Figure 11, it is preferable that the other side coupling portion 22 faces the one side coupling portion 21 in the radial direction Y. This makes it easier to push the shaft 31 in the axial direction X.

[0047] As shown in Figures 2, 10, and 11, it is preferable that the one-sided joint 21 and the other-sided joint 22 are symmetrical with respect to a second virtual plane V2 which is perpendicular to the first virtual plane V1 (described later) and contains the central axis of the shaft 31. This makes it easier to bend the second cylindrical portion 2 in a vertical direction Z perpendicular to the first virtual plane V1 relative to the first cylindrical portion 1, using the one-sided joint 21 and the other-sided joint 22 as axes. Furthermore, it is preferable that the one-sided joint 21 and the other-sided joint 22 have the same shape, but they may have different shapes or be similar in shape.

[0048] As shown in Figure 2, it is preferable that the first cylindrical portion 1 has a tapered portion 1T that tapers outward in the radial direction. Because the first cylindrical portion 1 has a tapered portion 1T that tapers outward from the radial center, the radial outer portions of the first cylindrical portion 1 and the second cylindrical portion 2 are less likely to come into direct contact with each other, making it easier to bend the second cylindrical portion 2 relative to the first cylindrical portion 1. It is preferable that the tapered portion 1T extends in the circumferential direction of the first cylindrical portion 1, and more preferably extends around the entire circumference of the first cylindrical portion 1. The angle of inclination of the tapered portion 1T with respect to the radial direction is preferably 3 degrees or more, and more preferably 6 degrees or more. This makes it easier to bend the second cylindrical portion 2 relative to the first cylindrical portion 1. On the other hand, the angle of inclination of the tapered portion 1T with respect to the radial direction is preferably 15 degrees or less, and more preferably 10 degrees or less. This makes it easier to push the shaft 31 in the axial direction X.

[0049] As shown in Figure 2, it is preferable that the first cylindrical portion 1 has a recess 1h adjacent to the first connecting portion 10 that is recessed toward the opposite side from the second cylindrical portion 2. The recess 1h provides space, making it easier for the first connecting portion 10 to move.

[0050] As shown in Figure 2, it is preferable that the second cylindrical portion 2 has a recess 2h adjacent to the second connecting portion 20 that is recessed toward the opposite side from the first cylindrical portion 1. The recess 2h provides space, making it easier for the second connecting portion 20 to move.

[0051] As shown in Figure 6, the axial length X of the first cylindrical portion 1, L1, may be shorter than the radial length Y of the first cylindrical portion 1, L2. By having multiple such cylindrical portions, the shaft 31 can easily form a smooth, arc-shaped curved portion during operation. On the other hand, length L1 may be longer than length L2, or it may be the same length as length L2. Furthermore, the outer diameter of the first cylindrical portion 1 is preferably 2 mm or more and 10 mm or less, and more preferably 5 mm or more and 8 mm or less.

[0052] As shown in Figure 2, it is preferable that the first cylindrical portion 1 and the second cylindrical portion 2 do not come into direct contact with each other when they are not bent. This makes it easier to bend the second cylindrical portion 2 relative to the first cylindrical portion 1.

[0053] The first cylindrical portion 1, the second cylindrical portion 2, the first connecting portion 10, and the second connecting portion 20 preferably have the same material, and more preferably are made of the same material. As shown in Figures 2, 10, and 11, the first cylindrical portion 1 and the second cylindrical portion 2 preferably have the same shape, and more preferably are made of the same shape. This makes it easier to distribute the force applied during bending, makes it easier to manufacture the shaft 31, and reduces manufacturing costs.

[0054] The shaft 31 preferably has a plurality of first cylindrical portions 1 and a plurality of second cylindrical portions 2. For example, when the combination of the first cylindrical portion 1, the first connecting portion 10, the second connecting portion 20, and the second cylindrical portion 2 is considered as one block, it is preferable that the plurality of blocks are connected in the axial direction X. The connections between each block are preferably connected in the same way as the connections between the first cylindrical portion 1 and the second cylindrical portion 2.

[0055] As shown in Figure 13, the axial length X of the second cylindrical portion 2 may be shorter than the axial length X of the first cylindrical portion 1. This improves the flexibility of the tip end of the shaft 31. Also, as shown in Figure 13, the axial length X of the multiple cylindrical portions may decrease as they move toward the tip end of the shaft 31.

[0056] As shown in Figures 2 and 11, the first cylindrical portion 1 is divided into a first region 1A and a second region 2A of the first cylindrical portion 1, which is a first virtual plane V1 that includes the central axis of the shaft 31 and extends along the central axis, and which becomes a line when the shaft 31 is oriented in the direction in which the width of the first joint portion 10 is maximized at the center point 10c of the first joint portion 10. Preferably, the first region 1A has a first lumen 1L extending in the axial direction X, and the second region 2A has a second lumen 2L extending in the axial direction X.

[0057] As shown in Figures 2-4 and Figure 11, by placing a first operating wire 33a in the first lumen 1L and a second operating wire 33b in the second lumen 2L, and by pulling one wire and loosening the other, the shaft 31 can be bent in a first direction in the vertical direction Z perpendicular to the first virtual plane V1, and in a second direction opposite to the first direction. This makes the shaft 31 a movable shaft that can be bent in the first and second directions. On the other hand, in response to external forces that the first cylindrical part 1 and the second cylindrical part 2 receive from multiple directions, the first connecting part 10 and the second connecting part 20 extend or compress, allowing flexibility not only in the vertical direction Z but also in the radial direction Y, thus making it easier to insert the shaft 31 into body tissue.

[0058] The first cylindrical portion 1 may have a number of lumens extending in the axial direction X corresponding to the number of operating wires placed inside. In this case, it is preferable that the number of lumens in the first region 1A and the second region 2A are the same.

[0059] As shown in Figure 11, it is preferable that the first lumen 1L and the second lumen 2L face each other in the vertical direction Z perpendicular to the first virtual plane V1. This allows the first operating wire 33a and the second operating wire 33b to be positioned facing each other in the vertical direction Z. This makes it easier to bend the shaft 31 in the vertical direction Z.

[0060] As shown in Figure 12, it is preferable that the tips of the first operating wire 33a and the second operating wire 33b are directly or indirectly fixed to the third cylindrical portion 3 located at the tip end of the shaft 31. This allows the second cylindrical portion 2 to be bent in a first direction of the Z perpendicular to the first cylindrical portion 1 by pulling the second operating wire 33b and loosening the first operating wire 33a, as shown in Figure 3. On the other hand, as shown in Figure 4, the second cylindrical portion 2 can be bent relative to the first cylindrical portion 1 in a second direction opposite to the first direction by pulling the first operating wire 33a and loosening the second operating wire 33b. When the tips of the first operating wire 33a and the second operating wire 33 are indirectly fixed to the third cylindrical portion 3, for example, the tips of the first operating wire 33a and the second operating wire 33b can be fixed to a ring-shaped member by welding, brazing, etc., and the ring-shaped member can be fixed to the third cylindrical portion 3 by bonding, brazing, etc. The ring-shaped member preferably contains metal, and preferably is made of metal.

[0061] The first operating wire 33a and the second operating wire 33b preferably contain metal, and more preferably are made of metal. The first operating wire 33a and the second operating wire 33b may also contain resin, and may be made of resin. The number of operating wires is not limited to two; for example, there may be two to six wires, or two to four wires. Specifically, the shaft 31 may be configured to bend not only in a first direction in the vertical direction Z and a second direction opposite to the first direction by operating multiple operating wires, but also in a third direction toward one side of the direction perpendicular to the virtual plane including the first and second directions, and a fourth direction opposite to the third direction.

[0062] As shown in Figure 11, the first cylindrical portion 1 preferably has a third lumen 3L extending in the axial direction X. A cable can be placed in the third lumen 3L. Furthermore, as shown in Figure 12, an objective lens 34 can be placed at the end of the cable. It is preferable that an image sensor is integrally provided on the objective lens 34. When multiple cables are arranged, an objective lens 34 may be placed at the end of the first cable, and an illumination device may be placed at the end of the second cable. The number of illumination devices may be two or more. It is preferable that the illumination device has a light-emitting diode (LED). Examples of cables include electric wires and optical fibers. It is also preferable that the cable has an insulating film.

[0063] As shown in Figure 11, it is preferable that the first cylindrical portion 1 has a fourth lumen 4L extending in the axial direction X. The fourth lumen 4L can be used as a forceps insertion hole, a fluid injection hole, a suction hole, etc. Examples of fluids injected into the body through the fluid injection hole include liquids and gases.

[0064] As shown in Figure 11, the fourth lumen 4L is preferably located in the radial direction Y between one side joint 11 and the other side joint 12 of the first joint 10. Furthermore, the fourth lumen 4L is preferably located in the radial direction Y between one side joint 21 and the other side joint 22 of the second joint 20. This makes it easier to insert forceps or the like into the fourth lumen 4L.

[0065] The second cylindrical portion 2 preferably has a first lumen 1L, a second lumen 2L, a third lumen 3L, and / or a fourth lumen 4L, and more preferably has a first lumen 1L, a second lumen 2L, a third lumen 3L, and a fourth lumen 4L.

[0066] Preferably, the shaft 31 has a cylindrical portion adjacent to the second cylindrical portion 2 on the side of the second cylindrical portion 2 opposite to the side facing the first cylindrical portion 1. Preferably, the shaft 31 further has at least one connecting portion that connects the cylindrical portion and the second cylindrical portion 2. Preferably, the at least one connecting portion includes a connecting portion having the same shape as at least one first connecting portion 10, and more preferably includes a connecting portion having the same shape as at least one second connecting portion 20.

[0067] Preferably, the shaft 31 has a cylindrical portion adjacent to the first cylindrical portion 1 on the side opposite to the side of the first cylindrical portion 1 that faces the second cylindrical portion 2. Preferably, the shaft 31 further has at least one connecting portion that connects the cylindrical portion and the first cylindrical portion 1. Preferably, the at least one connecting portion includes a connecting portion having the same shape as at least one first connecting portion 10, and more preferably includes a connecting portion having the same shape as at least one second connecting portion 20.

[0068] The first cylindrical part 1, the second cylindrical part 2, the third cylindrical part 3, the first connecting part 10, and the second connecting part 20 each preferably contain a resin, and more preferably consist of a resin. This improves flexibility. Furthermore, the endoscope 30 can be made into a disposable endoscope. The resin is preferably a thermoplastic resin, a thermoplastic elastomer, or a mixture thereof. Examples of thermoplastic elastomers include polyester elastomers and polyamide elastomers. Examples of thermoplastic resins include polyester such as polyethylene terephthalate, polyethylene, polypropylene, polybutene, polyolefins such as ethylene-propylene copolymer and ethylene-vinyl acetate copolymer, polyamides, polyimides, polyamide-imides, polyurethanes, and fluororesins. Examples of fluororesins include polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer. These may be used individually or in combination of two or more. Each part is preferably manufactured by injection molding, but may also be manufactured using a 3D printer or the like. Alternatively, each part may be manufactured individually and joined together by adhesive, welding, etc., but it is preferable to mold each part together as a single unit by injection molding or the like.

[0069] The first cylindrical portion 1, the second cylindrical portion 2, the third cylindrical portion 3, the first connecting portion 10, and the second connecting portion 20 are preferably made of the same material, and more preferably made of the same material. This makes it easier to distribute the force applied during bending, makes it easier to manufacture the shaft 31, and reduces manufacturing costs.

[0070] As shown in Figures 2 and 12, the third cylindrical portion 3 located at the tip end of the shaft 31 preferably has a cylindrical portion on the side opposite to the connection with the other cylindrical portions. The objective lens 34 is preferably arranged in the cylindrical portion. The ends of the first operating wire 33a and the second operating wire 33b are preferably fixed directly or indirectly inside the cylindrical portion. As shown in Figure 2, the third cylindrical portion 3 preferably has a recess 3h that is recessed toward the tip of the shaft 31. The recess 3h provides space, making it easier for the second connection portion 20 to move.

[0071] The shaft 31 preferably has a protective tube in which a first cylindrical portion 1, a first connecting portion 10, and a second cylindrical portion 2 are arranged in its lumen. The protective tube can protect the first cylindrical portion 1 and the second cylindrical portion 2. It is preferable that a second connecting portion 20 is further arranged in the lumen of the protective tube. It is preferable that a third cylindrical portion 3 is further arranged in the lumen of the protective tube. The protective tube preferably contains a resin, and more preferably is made of a resin. The resin is preferably a thermoplastic resin, a thermoplastic elastomer, or a mixture thereof. Examples of thermoplastic elastomers include polyester elastomers and polyamide elastomers. Examples of thermoplastic resins include polyester such as polyethylene terephthalate, polyethylene, polypropylene, polybutene, polyolefins such as ethylene-propylene copolymer and ethylene-vinyl acetate copolymer, polyamide, polyimide, polyamide-imide, polyurethane, and fluororesin. Examples of fluororesin include polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer. These may be used individually, or two or more may be used in combination.

[0072] As shown in Figure 1, it is preferable that the endoscope 30 has a handle 32 located at the proximal end of the shaft 31. The handle 32 should be configured so that the user can grasp it.

[0073] The handle 32 preferably has an operating section 32A for operating the first operating wire 33a and the second operating wire 33b. Preferably, the base ends of the first operating wire 33a and the second operating wire 33b are connected to the operating section 32A directly or indirectly. For example, by rotating the operating section 32A to one side in the circumferential direction, one wire can be pulled and the other wire can be loosened. Figure 1 shows a cylindrical operating section 32A, but the operating section 32A may be dial-shaped. The operating section 32A may also have a rotating mechanism such as a pulley or sprocket.

[0074] Although not shown in the figures, it is preferable that the handle 32 has a connector portion to which a tube or the like for aspirating or supplying fluid can be connected. This allows for the aspiration of bodily fluids from or supplying fluid to bodily tissues via the fourth lumen 4L. Examples of fluids include liquids and gases. Although not shown in the figures, the base end of the handle 32 may be connected via a connector to an external cable connected to an external device such as a video processor.

[0075] The endoscope 30 is preferably capable of observing the digestive tract, such as the esophagus, stomach, small intestine, and large intestine; blood vessels, such as coronary arteries; respiratory organs, such as the thoracic cavity and bronchi; urinary organs, such as the bladder and renal pelvis; pancreas; and biliary tract. Furthermore, the endoscope 30 is preferably a disposable endoscope. This helps prevent infection in the person being observed. [Explanation of Symbols]

[0076] 1, 2, 3 First cylindrical part, second cylindrical part, third cylindrical part 1h, 2h, 3h recess 1A, 2A 1st area, 2nd area 1L, 2L, 3L, 4L 1st lumen, 2nd lumen, 3rd lumen, 4th lumen 1T Tapered section 10, 11, 12 First joint, one side joint, other side joint 10a End portion on the first cylindrical part side 10b End of the second cylindrical section 10c center point 10d, 20d widening section 10e, 20e curved section 10f, 20f reduced width part 10g, 20g curved section 20, 21, 22 Second joint, one side joint, other side joint 20a End portion on the first cylindrical part side 20b End portion on the second cylindrical part side 20c center point L1 Axial length L2 is the radial length. 30 Endoscopes 31 shafts 32 handle 32A Operation section 33a, 33b Operating wires 34 Objective lens L virtual line V1, V2 First virtual plane, Second virtual plane W is the direction of inclination. X-axis direction Y radial direction Z vertical direction

Claims

1. It is the shaft of the endoscope, A first cylindrical portion having an axial direction, The first cylindrical portion and the second cylindrical portion adjacent to it in the axial direction, It has at least one first connecting portion that extends in an inclined direction with respect to the axial direction of the first cylindrical portion and connects the first cylindrical portion and the second cylindrical portion, It has at least one second connecting portion that extends in parallel with the at least one first connecting portion and is connected to the first cylindrical portion and the second cylindrical portion, Each of the at least one first connecting portion and the at least one second connecting portion has a widened portion that widens towards the second cylindrical portion. Each of the at least one first connecting portion and the at least one second connecting portion has a narrowed width portion that becomes narrower as it approaches the second cylindrical portion. The narrowed portion is located closer to the second cylindrical portion than the widened portion and is adjacent to the widened portion on the shaft of the endoscope.

2. The shaft of the endoscope according to claim 1, wherein the inclination direction is the direction in which the shaft is inclined with respect to the axial direction in a first side view of the shaft, where the shaft is oriented in a direction in which the width of the first joint at the center point of the first joint is maximized.

3. The shaft of the endoscope according to claim 2, wherein, in a second side view of the shaft when the shaft in the first side view is rotated 90 degrees in the circumferential direction, the angle between a virtual straight line passing through the end of the first joint on the first cylindrical part side and the end of the first joint on the second cylindrical part side and the radial direction of the first cylindrical part is 70 degrees or more and 110 degrees or less.

4. The shaft of the endoscope according to claim 1, wherein the outer edge of the widened portion has a curved portion.

5. The shaft of the endoscope according to claim 4, wherein the outer edge of the narrowed portion has a curved portion.

6. The shaft of an endoscope according to claim 1 or 2, wherein the at least one first connecting portion has a one-side connecting portion located on one side of the radial direction of the first cylindrical portion and a other-side connecting portion located on the other side.

7. The shaft of the endoscope according to claim 6, wherein the other coupling portion is opposite to the one coupling portion in the radial direction.

8. The shaft of the endoscope according to claim 1, wherein the at least one second connecting portion has a one-side connecting portion located on one of the radial sides of the first cylindrical portion and a other-side connecting portion located on the other side.

9. The shaft of the endoscope according to claim 8, wherein the other coupling portion is opposite the one coupling portion in the radial direction.

10. The shaft of an endoscope according to claim 1 or 2, wherein the first cylindrical portion is divided into a first region and a second region of the first cylindrical portion by a first virtual plane that includes the central axis of the shaft and extends along the central axis, and which forms a line when the shaft is oriented in a direction that maximizes the width of the first joint at the center point of the first joint, the first region having a first lumen extending in the axial direction, and the second region having a second lumen extending in the axial direction.

11. The shaft of an endoscope according to claim 1 or 2, wherein the surface of the end of the first cylindrical portion adjacent to the second cylindrical portion is inclined with respect to the radial direction, and the distance between the first cylindrical portion and the second cylindrical portion increases further outward than the portion of the first cylindrical portion closer to the center in the radial direction.

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