JP5030658B2 - Endoscope - Google Patents

Description

  The present invention relates to an endoscope having a bending portion that can be bent at a part of a flexible insertion portion in a medical endoscope or an industrial endoscope.

  For example, a medical endoscope will be described. A bending portion provided in a part of a flexible insertion portion to be inserted into a body cavity has a plurality of bending pieces arranged linearly in the axial direction of the insertion portion. The bending pieces are connected to each other by pivoting the edges of the adjacent bending pieces with a rivet pin or the like. An operation portion is provided at the base end portion of the insertion portion, and an operation wire for bending the bending portion is inserted into the insertion portion so as to be able to advance and retract.

  When the operation wire is pulled along with the bending drive operation in the operation unit, each bending piece rotates in the direction of pulling around the rivet pin, and the bending portion is moved until the edges of the adjacent bending pieces come into contact with each other. It can be curved.

  In this way, in the bending portion of the insertion portion of the endoscope, the bending pieces of the plurality of tubular members that are linearly connected in the axial direction of the insertion portion have a D-shaped cross section, and these bending pieces can be freely rotated by the rivet pins. Connect to An endoscope is known in which a bending portion is bent in a desired direction when an operation wire is pulled to bend the bending portion (see, for example, Patent Document 1).

  In addition, when the edges of the adjacent bending pieces do not contact each other in the vicinity of the edge of the adjacent bending piece, a convex portion that contacts the edge of one of the bending pieces is provided on the other bending piece so as to deviate from a predetermined bending angle. There is also known one that prevents the phenomenon of so-called piece dropping, in which curved pieces rotate, for example (see Patent Document 2, for example).

Furthermore, in consideration of insertion of optical fiber bundles, tubes, signal lines, operation wires and other built-in items inside the insertion portion including the bending portion, the inner side of the bending piece protrudes inward from the wire guide, There is also known one provided with a climbing restricting member that restricts the climbing of a built-in object (for example, see Patent Document 3).
JP 7-59728 A JP 2000-316797 A JP 2002-320587 A

  By the way, in recent years, endoscopes have been made thinner in order to reduce the invasiveness of patients. In order to reduce the diameter of the insertion part, it is necessary to reduce the size of each part, but the insertion part including the bending part is inserted with built-in items such as an optical fiber bundle, a tube, a signal line, and an operation wire. In order for these built-in functions to fulfill their functions, the interior must be secured to a space area that meets and fits them.

  Accordingly, it is necessary to reduce the thickness of each part in order to satisfy the above-described requirements, and the bending piece made of a tubular member constituting the bending portion is also reduced in diameter, and the thickness thereof is further reduced. Therefore, depending on the processing error, the edges of adjacent bending pieces do not come into contact with each other, and there is a case where a so-called piece dropping phenomenon occurs in which the bending pieces turn more than the design value.

  That is, the bending angle and the bending radius of the bending portion are determined by abutting between the edge portions of adjacent bending pieces, but by reducing the thickness of the bending piece, the range of the contact surface (line or point) is reduced. The end edge part of the bending piece enters the inside or the outside of the end edge part of the adjacent bending piece, and a desired bending angle cannot be obtained. Furthermore, there is a possibility that the built-in object may be damaged due to sharp bending.

  For example, in Patent Document 1, the bending piece of the tubular member has a D-shaped cross section, but the edges of the adjacent bending pieces have the same shape. There is a possibility that a phenomenon of so-called piece dropping occurs, in which the curved pieces rotate more than the design value without contacting each other.

  Moreover, in patent document 2, although the phenomenon of what is called a piece dropping is prevented by a convex part, since the convex part is provided in the outer peripheral surface of the bending piece, there exists a problem that the outer diameter of an insertion part becomes thick. is there.

  Furthermore, Patent Document 3 is a structure in which a climbing restricting member for restricting the climbing of the built-in object is separately provided inside the bending piece, and the jumping restricting member causes the internal space of the bending piece to be narrowed, and the layout for inserting the built-in object is difficult Therefore, it is considered that the assembly workability is deteriorated.

  The present invention has been made paying attention to the above circumstances, and the object of the present invention is to provide an end of an adjacent bending piece even if the bending piece constituting the bending portion is thinned as the diameter of the insertion portion is reduced. An endoscope capable of preventing a piece dropping phenomenon in which edges are securely in contact with each other, greatly deviating from a predetermined bending angle, and the bending pieces are rotated, and damage to built-in objects can be prevented. It is to provide.

  In order to achieve the above object, according to the present invention, an operation unit is coupled to a proximal end side of an insertion portion to be inserted into a body cavity, and a plurality of the operation portions are disposed on a distal end side of the insertion portion. In an endoscope having a bending portion in which bending pieces are sequentially connected along the axial direction of the insertion portion, the bending piece is positioned on an axis in the bending direction of the bending portion at least at an end edge portion of the adjacent bending piece, and A protrusion protruding inside the bending piece is provided, and the protrusions of the adjacent bending pieces are different in shape.

  A second aspect of the present invention is characterized in that the protrusion of the first aspect has an arc shape having different curvature radii between the adjacent bending pieces.

  A third aspect of the present invention is characterized in that the projecting portion of the first aspect has a D-cut shape having a different cut width between the adjacent bending pieces.

  A fourth aspect of the present invention is characterized in that the protrusions according to any one of the first to third aspects are shifted in the circumferential direction of the bending pieces between the adjacent bending pieces.

  According to a fifth aspect of the present invention, the protrusions according to any one of the first to fourth aspects are provided in a substantially symmetrical pair with a connecting shaft center that rotatably connects the bending pieces to each other. Features.

  In a sixth aspect of the present invention, the protrusions according to any one of the first to fourth aspects are provided in substantially symmetrical pairs with a connecting shaft center that rotatably connects the bending pieces to each other. The protrusions formed have different shapes.

  A seventh aspect of the present invention is characterized in that the projecting portion of the first to sixth aspects also serves as a wire guide for an operation wire for performing a bending operation on the bending portion.

  An eighth aspect of the present invention is characterized in that the protrusions of the first to seventh aspects are provided only at an end edge portion of the bending piece.

  A ninth aspect of the present invention is characterized in that the protrusions of the first to seventh aspects are provided over the entire length of the bending piece in the axial direction.

  According to the present invention, at least the edge portion of the adjacent bending piece of the bending portion of the insertion portion is provided with a protruding portion that protrudes inside the bending piece, and the protruding portions of the adjacent bending pieces are configured to have different shapes. It is characterized by. Therefore, even if the bending piece constituting the bending portion is thinned with the reduction in the diameter of the insertion portion, the edges of the adjacent bending pieces reliably come into contact with each other and greatly deviate from a predetermined bending angle. It is possible to prevent the drop-off phenomenon that the lens rotates, and to prevent damage to the built-in objects. Furthermore, by providing a protrusion on a part of the bending piece, the manufacturing accuracy and the assembly accuracy of the bending piece are not required, so that the cost can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 to 4 show a first embodiment, and FIG. 1 is an overall configuration diagram of an endoscope 1. The endoscope 1 includes an insertion unit 2 and an operation unit 3. The operation unit 3 is provided with an air / water supply button 4, a forceps insertion cap 5, a bending operation knob 6, and the like, and a universal cord 7 is connected thereto.

  The insertion portion 2 includes a flexible portion 8, a bending portion 9 connected to the distal end, and a tip constituting portion 10 provided at the forefront of the bending portion 9, and includes an image transmission signal line and an illumination portion. A fiber, a tube for inserting a forceps tube, and the like are inserted, and these are fixed to the distal end component 10 on the distal end side.

  FIG. 2 shows the internal structure of the bending portion 9 in two vertical directions, and a plurality of bending pieces 11 are sequentially arranged in series along the axial direction of the insertion portion 2 inside the outer tube (not shown). The adjacent bending pieces 11 are rotatably connected by a rivet-shaped shaft pin 12.

  3 and 4 show the bending piece 11, FIGS. 3A and 3B are cross-sectional views of adjacent bending pieces 11, and FIG. 4 is a perspective view of the bending piece 11. The bending piece 11 is made of a thin metal tubular member, and the ear-shaped connecting portions 13 protrude integrally at the positions of the left and right portions around the distal end edge 11a and the proximal end edge 11b. And is formed symmetrically. Each connecting portion 13 is provided with a shaft hole 14. The shaft pins 12 are inserted into the respective sets of the shaft holes 14 of the corresponding connecting portions 13 of the adjacent bending pieces 11, and are rotatable in two directions up and down with the shaft pin 12 as a fulcrum. Indicates an axis in the bending direction, and the axis S is orthogonal to the axial direction of the shaft pin 12.

  In this way, adjacent bending pieces 11 are connected in series. A cutout portion 15 is formed on each of the distal end edge 11a and the proximal end edge 11b of the bending piece 11 so as to form linear end faces on the upper side and the lower side with respect to the central axis O of the bending piece 11, respectively. Has been. The end face of each notch 15 is inclined toward the center side of its own bending piece 11 toward the outer side, and the extension of the inclined end face is formed so as to pass through the center of the shaft hole 14 or the vicinity thereof. .

  As shown in FIG. 2, a plurality of bending pieces 11 connected in series will be described. Among the plurality of bending pieces 11, the proximal end side edge 11 b of the adjacent bending piece 11 on the distal end side is shown in FIG. The distal end side edge 11a of the bending piece 11 on the proximal end side which is formed as shown in a) and adjacent thereto is configured as shown in FIG. That is, the proximal end side edge 11b of the bending piece 11 on the distal end side is formed on the upper and lower portions of the outer peripheral wall at a position biased to the left side in the figure across the axis S of the bending piece 11 as shown in FIG. Is provided with a protrusion 16 having a large radius of curvature that protrudes toward the central axis O. As shown in FIG. 3B, the distal end edge 11a of the bending piece 11 on the proximal end side is centered on the upper and lower portions of the outer peripheral wall at a position biased to the left side in the figure across the axis S of the bending piece 11. A protrusion 17 having a small radius of curvature that protrudes toward the axis O is provided.

  Since the end portions of the adjacent bending pieces 11 are different in shape from the protrusions 16 and 17, the distal end side edge 11a and the proximal end side edge 11b of the bending piece 11 are bent along with the bending of the bending portion 9. When the two come into contact with each other, the protrusions 16 and 17 partially come into contact with each other to prevent the leading end side edge 11a and the base end side edge 11b from entering the inside or the outside, thereby preventing the piece from falling.

  Further, as shown in FIGS. 3 (a) and 3 (b), in the substantially intermediate portion in the axial direction of the bending piece 11, there are central axes on the upper and lower portions of the inner peripheral wall at a position biased to the right side in the drawing across the axis S. A wire guide 18 having a radius of curvature projecting toward O is provided. The wire guide 18 is formed by inserting two cut lines parallel to the peripheral wall of the bending piece 11 and projecting between the cut lines toward the central axis O. These wire guides 18 are shown in FIG. In this way, the bending operation wire 19 is inserted. The wire guide 18 may weld a ring of another member to the inner wall of the bending piece 11.

  Further, a treatment instrument insertion channel pipe line 21 as a built-in object, a light guide fiber 22, and a flexible built-in object 23 such as a signal line for transmitting a signal from the image sensor are inserted into the internal space portion 20 of the bending piece 11. Has been. The largest diameter treatment instrument insertion channel pipe line 21 is arranged on the left side of the axis S, the light guide fiber 22 and the flexible built-in object 23 are arranged on the right side of the axis S, and the bending resistance of the bending portion 9 during bending is arranged. It is configured so as not to interfere.

  Next, the operation of this embodiment will be described.

  When the bending operation wire 19 is pulled in accordance with the bending drive operation of the bending operation lever 6 of the operation unit 3 on the hand side by the surgeon, the distal end configuration unit 10 to which the distal end portion of the pulled bending operation wire 19 is fixed is obtained. The curved portion 9 is drawn toward the proximal end. At this time, the bending pieces 11 are rotated around the shaft pins 12 by the rotational moment generated around the shaft pins 12 and are rotated until the end surfaces of the notch portions 15 of the adjacent bending pieces 11 come into contact with each other.

  Here, when the inner diameter at the edge of the bending piece 11 is processed to be slightly larger than a predetermined dimension, or becomes obsolete, the shaft pin 12 and the shaft hole 14 at the connecting portion 13 are rattled. In this case, the end surfaces of the cutout portions 15 of the bending pieces 11 may not contact each other. However, when the distal end side edge 11a and the proximal end side edge 11b of the adjacent bending pieces 11 are in contact with each other, the shapes of the protrusions 16 and 17 provided on the end edge portion are different. 17 is partially in contact with each other and the bending pieces 11 do not rotate any more. That is, it is possible to prevent the leading edge 11a and the proximal edge 11b from entering the inside or the outside and dropping the pieces.

  Accordingly, it is possible to prevent a drop-off phenomenon in which the bending pieces are rotated by greatly deviating from the predetermined bending angle of the bending portion, and it is possible to prevent damage to the built-in objects. As a result, the durability of the endoscope is improved, and the user does not have to worry about excessive handling.

  FIG. 5 shows a second embodiment, and the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. 5A and 5B are cross-sectional views of adjacent bending pieces 11. In this embodiment, the base end side edge 11b of the bending piece 11 on the distal end side is an outer peripheral wall at a position biased to the left side in the drawing with the axis S of the bending piece 11 in between, as shown in FIG. Protrusions 24 made of inclined surfaces projecting toward the central axis O are provided at the upper and lower portions. As shown in FIG. 5 (b), the distal end side edge 11 a of the bending piece 11 on the proximal end side is a protrusion formed of a flat surface protruding toward the central axis O at the upper and lower portions on the axis S of the bending piece 11. A portion 25 is provided.

  In this way, the end edges of the adjacent bending pieces 11 are provided at different positions in the circumferential direction of the bending piece 11 from the protrusions 24 and 25, and one of them is reversely inclined and the other is parallel, so that the bending portion 9 When the distal end side edge 11a and the proximal end edge 11b of the bending piece 11 come into contact with each other, the protrusions 24 and 25 partially contact with each other so that the distal end side edge 11a and the proximal end side are in contact with each other. The edge 11b enters the inside or the outside and prevents the piece from falling.

  6 and 7 show a third embodiment, and the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. FIGS. 6A and 6B are cross-sectional views of adjacent bending pieces 11, and FIG. 7 is a perspective view of the bending piece 11.

  As shown in FIG. 6A, the proximal end edge 11b of the distal bending piece 11 protrudes toward the central axis O at the upper and lower portions of the outer peripheral wall located on the axis S of the bending piece 11. A protrusion 26 having a large curvature radius is provided. The distal end side edge 11a of the bending piece 11 on the proximal end side protrudes toward the central axis O at the upper and lower portions of the outer peripheral wall located on the axis S of the bending piece 11 as shown in FIG. A protrusion 27 having a small curvature radius is provided.

  Since the end portions of the adjacent bending pieces 11 have different shapes from the protrusions 26 and 27, the distal end side edge 11a and the proximal end side edge 11b of the bending piece 11 are bent along with the bending of the bending portion 9. When the two come into contact with each other, the projections 26 and 27 partially come into contact with each other to prevent the leading end side edge 11a and the base end side edge 11b from entering the inside or the outside, thereby preventing the piece from falling. Further, a partition wall 28 that partitions the protrusions 26 and 27 is provided at an intermediate portion in the axial direction of the bending piece 11.

  The partition wall 28 is formed with a communication hole that connects the protrusions 26 and 27, and a wire guide 29 is formed by the communication hole. That is, the protrusions 26 and 27 protrude inward from the outer peripheral wall of the bending piece 11, and a dead space is formed between the outer peripheral wall of the bending piece 11 and the bottoms of the protrusions 26 and 27. The wire guide 29 is formed using the above. Therefore, unlike the first and second embodiments, it is not necessary to separately provide a protrusion on the peripheral wall of the bending piece 11 in order to form the wire guide 18, and the internal space portion 20 of the bending piece 11 can be widened. it can.

  FIG. 8 shows a fourth embodiment, and the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. 8A and 8B are cross-sectional views of adjacent bending pieces 11.

  As shown in FIG. 8A, the proximal end edge 11b of the distal bending piece 11 is centered on the upper and lower portions of the outer peripheral wall at a position biased to the left in the figure across the axis S of the bending piece 11. A protrusion 30 having a large radius of curvature that protrudes toward the axis O is provided. As shown in FIG. 8B, the distal end side edge 11a of the bending piece 11 on the proximal end side is centered on the upper and lower portions of the outer peripheral wall at a position biased to the left side in the drawing across the axis S of the bending piece 11. A protrusion 31 having a small radius of curvature protruding toward the axis O is provided.

  In this way, since the edge portions of the adjacent bending pieces 11 are different in shape from the protrusions 30 and 31, the distal end side edge 11a and the proximal end side edge 11b of the bending piece 11 are accompanied by the bending of the bending portion 9. When the two come into contact with each other, the projections 26 and 27 partially come into contact with each other to prevent the leading end side edge 11a and the base end side edge 11b from entering the inside or the outside, thereby preventing the piece from falling. Further, a partition wall 32 that partitions the protrusions 30 and 31 is provided at an intermediate portion in the axial direction of the bending piece 11. The partition wall 32 is formed with a communication hole that connects the protrusions 30 and 31, and a wire guide 33 is formed by the communication hole. Therefore, as in the third embodiment, it is not necessary to provide a separate protrusion on the peripheral wall of the bending piece 11 in order to form the wire guide 18, and the internal space 20 of the bending piece 11 can be widened.

  FIG. 9 shows a fifth embodiment, and the same components as those in the first and fourth embodiments are denoted by the same reference numerals and description thereof is omitted. 9A and 9B are cross-sectional views of adjacent bending pieces 11. In the present embodiment, the treatment instrument insertion channel conduit 21, the light guide fiber 22, the signal line, and the like as a built-in object incorporated in the internal space 20 of the bending piece 11 with respect to the fourth embodiment are flexible. The arrangement of the built-in object 23 is changed, and there are the same effects as in the fourth embodiment.

  10 and 11 show a sixth embodiment, and the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. FIGS. 10A and 10B are cross-sectional views of adjacent bending pieces 11, and FIG. 11 is a perspective view of the bending piece 11.

  As shown in FIG. 10A, the proximal end edge 11b of the bending piece 11 on the distal end side is centered on the upper and lower portions of the outer peripheral wall at a position biased to the left side in the figure across the axis S of the bending piece 11. A protrusion 34 having a large curvature radius that protrudes toward the axis O is provided. As shown in FIG. 10B, the distal end edge 11a of the bending piece 11 on the base end side is centered on the upper and lower portions of the outer peripheral wall at a position biased to the right side in the figure across the axis S of the bending piece 11. A protrusion 35 having a small radius of curvature that protrudes toward the axis O is provided. As shown in FIG. 11, the protrusions 34 and 35 are provided over the entire length of the bending piece 11 in the axial direction.

  As described above, since the edge portions of the adjacent bending pieces 11 are different in the shapes of the protrusions 34 and 35, the leading edge 11a and the proximal edge 11b of the bending piece 11 are bent along with the bending of the bending portion 9. When the two come into contact with each other, the protrusions 34 and 35 partially come into contact with each other to prevent the leading end side edge 11a and the base end side edge 11b from entering the inside or the outside, thereby preventing the piece from falling.

  FIG. 12 shows a seventh embodiment, and the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. FIGS. 12A and 12B are cross-sectional views of adjacent bending pieces 11. As shown in FIG. 12A, the proximal end edge 11b of the bending piece 11 on the distal end side of the present embodiment is located above and below the outer peripheral wall at a position biased to the left in the figure across the axis S of the bending piece 11. The part is provided with a projecting part 36 made of a slope with a left slope projecting toward the central axis O. As shown in FIG. 12B, the distal end side edge 11a of the bending piece 11 on the proximal end side is centered on the upper and lower portions of the outer peripheral wall at a position biased to the right side in the drawing across the axis S of the bending piece 11. A protrusion 37 is provided that is formed of a right inclined surface protruding toward the axis O. These protrusions 36 and 37 are provided over the entire length of the bending piece 11 in the axial direction.

  As described above, since the edge portions of the adjacent bending pieces 11 have different inclination directions of the protrusions 36 and 37, the distal end side edge 11 a and the proximal end edge 11 b of the bending piece 11 are associated with the bending of the bending portion 9. When the two come into contact with each other, the protrusions 36 and 37 partially come into contact with each other to prevent the leading end side edge 11a and the base end side edge 11b from entering the inside or the outside, thereby preventing the piece from falling.

  FIG. 13 shows an eighth embodiment, and the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. FIGS. 13A and 13B are cross-sectional views of adjacent bending pieces 11. As shown in FIG. 13A, the proximal end edge 11b of the bending piece 11 on the distal end side of the present embodiment is located above and below the outer peripheral wall at a position biased to the left side in the figure across the axis S of the bending piece 11. The part is provided with a projecting part 38 made of a left inclined surface projecting toward the central axis O. As shown in FIG. 13B, the distal end side edge 11 a of the bending piece 11 on the proximal end side protrudes toward the central axis O on the upper and lower portions of the outer peripheral wall located on the axis S of the bending piece 11. Projections 39 made of a flat surface are provided in parallel. These protrusions 38 and 39 are provided over the entire length of the bending piece 11 in the axial direction.

  As described above, since the end portions of the adjacent bending pieces 11 are different in shape from the protrusions 38 and 39, the bending end 9 is bent and the distal end side edge 11 a and the proximal end edge 11 b of the bending piece 11 are changed. When the two come into contact with each other, the projections 38 and 39 partially come into contact with each other to prevent the front end side edge 11a and the base end side edge 11b from entering the inside or the outside, thereby preventing the piece from falling.

  14 and 15 show a ninth embodiment, and the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. FIGS. 14A and 14B are cross-sectional views of adjacent bending pieces 11, and FIG. 15 is a perspective view of the bending piece 11.

  In the bending piece 11 of the present embodiment, the ear-shaped connecting portions 13a and 13b are integrally projected at the positions of the left and right portions around the distal end edge 11a and the proximal end edge 11b. Although formed, the connecting portions 13a and 13b are arranged 180 degrees out of phase, and the connecting portions 13a and 13b are provided with shaft holes 14, respectively. Then, the shaft pin 12 is inserted into each pair of the shaft holes 14 of the corresponding connecting portions 13a and 13b of the adjacent bending pieces 11 in the same manner as in the first embodiment, and the shaft pin 12 is used as a fulcrum. -It is configured to be pivotably connected in four directions.

  The proximal end side edge 11b of the bending piece 11 on the distal end side protrudes toward the central axis O at the upper and lower portions of the outer peripheral wall located on the axis S of the bending piece 11 as shown in FIG. A protrusion 40 having a large curvature radius is provided. As shown in FIG. 14B, the distal end side edge 11 a of the bending piece 11 on the proximal end side protrudes toward the central axis O on the upper and lower portions of the outer peripheral wall located on the axis S of the bending piece 11. A protrusion 41 having a small curvature radius is provided. As shown in FIG. 15, the protrusions 40 and 41 are provided on the distal end side edge 11 a and the proximal end side edge 11 b of the bending piece 11.

  As described above, the edge portions of the adjacent bending pieces 11 are different in the shape of the protrusions 40 and 41, so that the distal end side edge 11 a and the proximal end of the bending piece 11 are associated with the bending of the bending portion 9 in the vertical and horizontal directions. When the side edge 11b abuts, the protrusions 40 and 41 partially abut to prevent the leading edge 11a and the proximal edge 11b from entering the inside or the outside and preventing the piece from falling. is doing. In the present embodiment, the protrusions 40 and 41 having different radii of curvature are provided, but the protrusion may be an inclined surface and a flat surface, or may be a combination of inclined surfaces having different inclined directions.

  According to the above configuration, even when the edges of the adjacent bending pieces do not come into contact with the edge portions of the adjacent bending pieces, the protruding pieces come into contact with each other, greatly deviating from a predetermined bending angle. It is possible to prevent the drop-off phenomenon that the lens rotates, and to prevent damage to the built-in objects. As a result, the durability of the endoscope is improved, and there is an effect that the user does not have to worry about excessive handling.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

1 is an overall configuration diagram of an endoscope according to a first embodiment of the present invention. FIG. The side view of the curved part of the embodiment. The embodiment is shown, (a) (b) is a cross-sectional view of an adjacent bending piece. The perspective view of the bending piece of the embodiment. The 2nd Embodiment of this invention is shown, (a) (b) is a cross-sectional view of the adjacent bending piece. The 3rd Embodiment of this invention is shown, (a) (b) is a cross-sectional view of the adjacent bending piece. The perspective view of the bending piece of the embodiment. The 4th Embodiment of this invention is shown, (a) (b) is a cross-sectional view of the adjacent bending piece. The 5th Embodiment of this invention is shown, (a) (b) is a cross-sectional view of the adjacent bending piece. The 6th Embodiment of this invention is shown, (a) (b) is a cross-sectional view of the adjacent bending piece. The perspective view of the bending piece of the embodiment. The 7th Embodiment of this invention is shown, (a) (b) is a cross-sectional view of the adjacent bending piece. The 8th Embodiment of this invention is shown, (a) (b) is a cross-sectional view of the adjacent bending piece. The 9th Embodiment of this invention is shown, (a) (b) is a cross-sectional view of the adjacent bending piece. The perspective view of the bending piece of the embodiment.

Explanation of symbols

2 ... Insertion part, 3 ... Operation part, 9 ... Bending part, 11 ... Bending piece, 16, 17 ... Projection part

Claims (9)

The operation unit is connected to the proximal end side of the insertion portion to be inserted into the body cavity, and a bending portion in which a plurality of bending pieces are sequentially connected to the distal end side of the insertion portion along the axial direction of the insertion portion. In an endoscope having
Protrusions that are located on an axis in the bending direction of the bending portion and project inside the bending piece are provided at least at an edge portion of the adjacent bending pieces, and the protrusions of the adjacent bending pieces are different in shape. An endoscope characterized by that.   The endoscope according to claim 1, wherein the protrusion has an arc shape with different curvature radii between the adjacent bending pieces.   The endoscope according to claim 1, wherein the protrusion has a D-cut shape with a cut width different between the adjacent bending pieces.   The endoscope according to any one of claims 1 to 3, wherein the protrusions are displaced in the circumferential direction of the bending pieces between the adjacent bending pieces.   5. The projection according to claim 1, wherein the protrusions are provided in a substantially symmetrical pair with a connecting shaft center that rotatably connects the bending pieces. Endoscope.   The protrusions are provided in substantially symmetrical pairs with a connecting shaft center that rotatably connects the bending pieces, and the protrusions forming a pair have different shapes. Item 5. The endoscope according to any one of Items 1 to 4.   The endoscope according to any one of claims 1 to 6, wherein the protrusion also serves as a wire guide of an operation wire for bending the bending portion.   The endoscope according to claim 1, wherein the protrusion is provided only at an end edge of the bending piece.   The endoscope according to claim 1, wherein the protrusion is provided over the entire length of the bending piece in the axial direction.

Images