JP2006254973A - Endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope capable of bending accurately at a target bending angle. <P>SOLUTION: The distal end of a first coil pipe 13, into which a bending wire 12 is inserted in such a way that the wire can move forward/backward, is fixed to the distal end of a flexible tube part 4, and the distal end of a second coil pipe 14, into which the bending wire 12 is inserted in such a way that the wire can move forward/backward, is fixed to the distal end of a bending part 5. A gap L is formed between the first coil pipe 13 and the second coil pipe 14 for limiting the operation stroke of the bending wire 12 when the bending part 5 is bent/operated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an endoscope that performs a bending operation by pulling a bending portion provided in an insertion portion to be inserted into a body cavity with a bending wire.

  At present, endoscopes that are inserted into body cavities and observe affected areas are generally widely used. This endoscope is configured such that the distal end portion can be bent for the purpose of observing the entire body cavity when inserted into the body cavity. Further, in order to reduce the blind spot to be observed, the distal end of the insertion portion is made soft so that the distal end can be easily bent.

  For example, Patent Document 1 shows an example of a configuration of a bending portion provided on the distal end side of an insertion portion of an endoscope. A plurality of bending pieces are sequentially connected to the bending portion along the axial direction of the insertion portion. Further, the distal end portion of the bending wire is connected to the distal end side of the bending portion. The proximal end portion of the bending wire is connected to the bending operation mechanism of the operation unit connected to the proximal end portion side of the insertion portion. Then, the bending operation mechanism is driven by operating the bending operation lever provided in the operation unit, and the bending operation of the bending unit is performed by pulling the bending wire.

  The bending operation mechanism that pulls the wire includes a drum that converts the operation force of the bending operation lever into the pulling force of the wire. The base end portion of the bending wire is fixed to the drum. Then, the drum is driven to rotate by operating the bending operation lever of the operation unit. Thus, in general, the insertion portion is configured to bend by applying a tensile force to the distal end of the bending portion via the wire in conjunction with the movement of the bending operation lever. Further, as the wire for transmitting the bending force, a wire composed of a pliable stranded wire that normally prevents buckling and obtains strength is used. It is known that a wire composed of such a stranded wire is untwisted when a tensile force is applied, and the wire is stretched according to the tensile force.

Furthermore, in general, an endoscope is often used for the purpose of performing treatment at the same time as observation, and therefore many endoscopes have a channel for inserting a treatment tool inside an insertion portion. A treatment tool is inserted into the endoscope channel and introduced into the body through the channel.
JP 2003-144382 A

  By the way, when a treatment instrument having a high bending resistance such as a biopsy forceps or a laser treatment instrument is inserted into the treatment instrument insertion channel inside the insertion section, the distal end portion of the endoscope is difficult to bend. Therefore, the bending operation of the distal end portion of the endoscope is performed with a larger operation force than the operation when the treatment instrument is not inserted. In this case, there is a possibility that the wire for transmitting the pulling force is extended and the desired stroke amount cannot be pulled. Thus, when the wire cannot be pulled with a desired stroke amount when operating the bending operation lever of the operation unit, the bending amount of the bending operation of the bending portion of the endoscope is insufficient. There is a possibility that it cannot be bent to the bending angle.

  However, since the insertion portion of the endoscope is inserted into the body cavity, the deformation state of the insertion portion of the endoscope cannot be confirmed visually. Therefore, the endoscope having the above-described conventional configuration has a problem that it is difficult to check whether the bending portion of the endoscope is correctly bent to the target bending angle during the bending operation of the bending portion of the endoscope.

  The present invention has been made paying attention to the above circumstances, and an object of the present invention is to provide an endoscope capable of easily confirming whether or not the bending portion is correctly bent to a target bending angle when the bending portion is bent. It is in.

  According to the first aspect of the present invention, the operation unit is connected to the proximal end side of the insertion portion to be inserted into the body cavity, and the insertion portion is connected to the elongated flexible tube portion and the distal end portion of the flexible tube portion. A bending portion that is connected and can be bent and deformed, and the bending portion includes a plurality of bending pieces that are sequentially connected along the axial direction of the insertion portion, and a distal end of a bending wire on a distal end side of the bending portion The flexible first guide is inserted through the bending wire so as to be able to advance and retreat in an endoscope for bending the bending portion by pulling the bending wire by a pulling means provided on the operation portion. Fixing the distal end portion of the tube to the distal end portion of the flexible tube portion, fixing the distal end portion of the flexible second guide tube through which the bending wire can be advanced and retracted, to the distal end portion of the bending portion; The bay during the bending operation of the bending portion between the first guide tube and the second guide tube An endoscope, characterized in that a gap for regulating the operation stroke of the wire.

  In the first aspect of the present invention, the first guide tube fixed to the flexible tube portion and the second guide tube fixed to the bending portion as the bending angle of the bending portion increases during the pulling operation of the bending wire. The gap between is narrowed. At this time, when the bending portion is operated to bend to the target bending angle, the user senses the touch when the first guide tube and the second guide tube come into contact with each other, so that the bending portion becomes the target curve. The state in which the bending operation is performed up to the angle can be recognized, and the bending operation can be correctly performed up to the target bending angle.

  According to the invention of claim 2, the operating portion is connected to the proximal end side of the insertion portion to be inserted into the body cavity, and the insertion portion is connected to the elongated flexible tube portion and the distal end portion of the flexible tube portion. A bending portion that is connected and can be bent and deformed, and the bending portion includes a plurality of bending pieces that are sequentially connected along the axial direction of the insertion portion, and a distal end of a bending wire on a distal end side of the bending portion The flexible first guide is inserted through the bending wire so as to be able to advance and retreat in an endoscope for bending the bending portion by pulling the bending wire by a pulling means provided on the operation portion. The distal end portion of the tube is fixed to the distal end portion of the flexible tube portion, and hits the distal end portion of the first guide tube at the middle of the bending wire disposed in the bending portion during the pulling operation of the bending wire. A protrusion-shaped stopper is provided, and the first guide tube and the scan are provided. An endoscope, characterized in that a gap for regulating the operation stroke of the bending wire during the bending operation of the bending portion between the Tsu path.

  According to the second aspect of the present invention, the first guide tube fixed to the flexible tube portion and the bending wire disposed in the bending portion as the bending angle of the bending portion increases during the pulling operation of the bending wire. The gap between the part and the stopper is narrowed. At this time, when the bending portion is bent to the target bending angle, the user detects a touch when the first guide tube fixed to the flexible tube portion comes into contact with the middle stopper of the bending wire. By doing so, it is possible to recognize the state in which the bending portion is bent to the target bending angle, and to perform the bending operation correctly to the target bending angle.

  According to a third aspect of the present invention, the bending wire uses a twisted wire obtained by twisting strands in a rope shape and then performing a drawing process or a continuous caulking process, and the guide tube is a multi-wire hollow cable coil. The endoscope according to claim 1 or 2, wherein the endoscope is used.

  In the invention of claim 3, a twisted wire obtained by twisting strands in a rope shape and then performing a drawing process or a continuous caulking process is used as a bending wire, and the guide tube is a multi-wire hollow cable coil. By using it, it is possible to minimize the elongation of the bending wire, and the amount of contraction of the flexible tube portion is also improved. Therefore, it is possible to minimize the phenomenon of bending over the bending wire elongation, and even when the load applied to the bending wire fluctuates, the bending operation can be correctly performed to the target bending angle even during high-weight traction operation. It is something that can be done.

  According to a fourth aspect of the present invention, the pulling means has a bending operation lever provided in the operation portion and a proximal end portion of the bending wire fixed, and converts the operation force of the bending operation lever into a force pulling the bending wire. And a bending mechanism that applies a pulling force to the distal end portion of the bending portion via the bending wire in conjunction with the movement of the bending operation lever to bend the bending portion. The internal view according to claim 1 or 2, further comprising position adjusting means for adjusting a position of a stopper for restricting an operating range of the lever by applying a predetermined pulling force within an elastic deformation range of the bending wire. It is a mirror.

  In the fourth aspect of the invention, during the operation of bending the bending portion, the bending operation lever of the operation portion is operated to drive the bending mechanism portion of the traction means. At this time, the drum is driven in conjunction with the movement of the bending operation lever to convert the operation force of the bending operation lever into a force for pulling the bending wire. Thereby, a pulling force is applied to the distal end portion of the bending portion via the bending wire, and the bending portion is operated to bend. Further, the position of the stopper that regulates the operation range of the bending operation lever is adjusted by applying a specified pulling force within the elastic deformation range of the bending wire by the position adjusting means. As a result, by adjusting the position with a margin for the amount of elongation when a tensile force within the elastic deformation range of the wire is applied, the stopper works when the operating lever is operated with force, and the wire is deformed or When a treatment tool with high bending resistance can be inserted and bending operation is required with a larger operating force than when the treatment tool is not inserted, the wire elongation can be expected in advance. Since the stopper is adjusted, it is possible to compensate for a stroke with insufficient elongation, and to perform a correct bending operation up to a target bending angle.

  According to the present invention, it is possible to easily confirm whether or not the bending portion is correctly bent to a target amount of bending angle during the bending operation of the bending portion.

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an overall view of an endoscope 1 according to the present embodiment. In the endoscope 1, an operation unit 3 is connected to a proximal end side of an insertion unit 2 that is inserted into a body cavity. The insertion portion 2 includes an elongated flexible tube portion 4 and a bending portion 5 that is connected to the distal end portion of the flexible tube portion 4 and is capable of bending deformation. In addition, a hard short tip constituent portion 6 is disposed at the most distal end portion of the insertion portion 2. A bending portion 5 is disposed between the tip constituting portion 6 and the flexible tube portion 4.

  An operation lever 7 for remotely bending the bending portion 5 is provided on the operation portion 3. The bending portion 5 can be bent by operating the operation lever 7.

  FIG. 2 shows the internal structure of the bending portion 5. In the bending portion 5, a plurality of node rings (curving pieces) 9 are arranged in parallel along the axial direction of the insertion portion 2 inside the outer tube 8. Each node ring 9 has projections for connection at both front and rear ends. A rear end protrusion of the front node ring 9 and a front end protrusion of the rear node ring 9 are sequentially connected by rivets 10 so as to be rotatable around the rivets 10.

  Further, the distal end portion of the most advanced node ring 9 a of the bending portion 5 is fixed to the proximal end portion of the distal end configuration portion 6. Further, the node ring 9 b at the rearmost end of the bending portion 5 is connected to a connection member 11 provided at the distal end of the flexible tube portion 4.

  A bending wire 12 for bending the bending portion 5 is inserted into the insertion portion 2 so as to be movable along the axial direction of the insertion portion 2. The distal end portion of the bending wire 12 is fixed to the most advanced node ring 9a by brazing or the like.

  Further, the bending wire 12 is inserted into two closely wound (first and second) coil pipes 13 and 14 as guide tubes in a state of being movable in the respective axial directions. The first coil pipe 13 as the first guide tube is disposed inside the flexible tube portion 4. The tip of the first coil pipe 13 is fixed to the connection member 11.

  In addition, the second coil pipe 14 as the second guide tube is disposed inside the bending portion 5. The tip of the second coil pipe 14 is brazed together with the bending wire 12 to the most advanced node ring 9a. Furthermore, the second coil pipe 14 is provided with an appropriate gap L between the first coil pipe 13 and the first coil pipe 13 when the curved portion 5 is straight. The gap L is set so as to regulate the operation stroke of the bending wire 12 when the bending portion 5 is bent.

  FIG. 3 shows the internal structure of the operation unit 3. Inside the operation unit 3, a bending mechanism unit 15 for bending the bending unit 5 is disposed. The bending mechanism portion 15 is provided with a disk-shaped drum (traction means) 16. The drum 16 is fixed to the casing member 17 of the operation unit 3 in a coaxial state with the operation lever 7 through a shaft 18 that is pivotally penetrated in an airtight state by an O-ring or the like.

  Furthermore, the base end side of the bending wire 12 is fixed around the drum 16 in a state where it can be wound. Then, the drum 16 is rotationally driven by the rotation operation of the operation lever 7 of the operation unit 3, and the bending wire 12 is pulled by the rotation of the drum 16. Thereby, the operation force of the operation lever 7 is converted into a force for pulling the bending wire 12 by the drum 16. Therefore, a pulling force is applied to the distal end portion of the bending portion 5 via the bending wire 12 in conjunction with the movement of the operation lever 7, thereby bending the bending portion 5.

  A stopper 19 that restricts the operating range of the operation lever 7 is provided inside the operation unit 3. Here, a lever cam 20 is connected to the drum 16. The stopper 19 is fixed in a state of being inserted into the rotation track of the lever cam 20. The rotation position of the drum 16 is regulated at a position where the lever cam 20 abuts against the stopper 19. The stopper 19 is provided with a long hole 21 for changing the abutting position with the lever cam 20. A threaded portion of a fixing screw (position adjusting means) 22 is inserted into the long hole 21. Then, the stopper 19 is moved along the elongated hole 21 by loosening the fixing screw 22 so that the position of the abutting position with the lever cam 20 can be adjusted. When adjusting the position of the stopper 19, in addition to the stroke amount when there is no load, the position adjustment is performed with a margin for the amount of elongation when a specified tensile force within the elastic deformation range of the bending wire 12 is applied. To do.

  Next, the operation of the above configuration will be described. When the bending portion 5 of the insertion portion 2 is operated to bend when the endoscope 1 according to the present embodiment is used, the operation lever 7 of the operation portion 3 is rotated. Here, for example, when the operation lever 7 is rotated in the clockwise direction in FIG. 3, the drum 16 is also rotated in the same direction by the shaft 18. As a result, the bending wire 12 moves to the right in FIG. Further, since the distal end of the bending wire 12 is fixed to the node ring 9a on the distal end side of the bending portion 5, all the node rings 9 rotate clockwise around the rivet 10, and as a result, the bending portion 5 It will be greatly curved along its entire length.

  Further, when the bending portion 5 is bent, the second coil pipe 14 moves so as to be close to the first coil pipe 13 according to the pulling stroke amount of the bending wire 12. At this time, when the bending wire 12 is further pulled until the bending angle of the bending portion 5 reaches an appropriate setting angle of, for example, about 90 °, the end surface of the rear end portion of the second coil pipe 14 is finally the first surface. It strikes against the end face of the front end of the coil pipe 13. As a result, the operator bends the bending portion 5 to the target bending angle by the touch of the hand when the end surface of the rear end portion of the second coil pipe 14 abuts the end surface of the front end portion of the first coil pipe 13. The operated state can be recognized. The amount of movement of the second coil pipe 14 is determined by the gap L, and the gap L becomes the pulling stroke of the bending portion 5 and generally restricts the bending angle.

  On the other hand, the stroke range of the operating lever 7 is such that when the second coil pipe 14 abuts on the first coil pipe 13 and the bending angle is regulated and then the operating lever 7 is further rotated, the bending wire 12 has its operating force. In response to this, elastic deformation and elongation occur, and the operation is performed for the excess stroke amount. In the present embodiment, the amount of surplus stroke is adjusted based on the characteristic table of the bending wire 12 so that the stopper 19 is adjusted to a position where a safety factor is calculated for the amount of force that causes elastic deformation. Finally, the lever cam 20 connected to the drum 16 hits the stopper 19 and the operation of the operation lever 7 is restricted.

  Normally, the above-described operation is performed. However, when a treatment instrument having a high bending resistance such as a biopsy forceps or a laser treatment instrument is inserted, the extra stroke covers the wire extension. Further, even when the operation lever 7 is operated with a full stroke, the bending wire 12 is set so as not to be deformed and stretched or torn.

  Therefore, the above configuration has the following effects. That is, in the endoscope 1 according to the present embodiment, the first and second coil pipes 13 and 14 that are closely wound as the guide tube of the bending wire 12 are provided, and the first coil inside the flexible tube portion 4 is provided. The tip of the pipe 13 is fixed to the connecting member 11, and the tip of the second coil pipe 14 inside the bending portion 5 is brazed and fixed to the most advanced node ring 9 a together with the bending wire 12. Further, the length of the second coil pipe 14 is set so as to restrict the operation stroke of the bending wire 12 during the bending operation of the bending portion 5 with the first coil pipe 13 in a state where the bending portion 5 is straight. An appropriate gap L is provided. Thus, the first coil pipe 13 fixed to the flexible tube portion 4 as the bending angle of the bending portion 5 increases during the operation of rotating the operation lever 7 of the operation portion 3 to pull the bending wire 12. And the second coil pipe 14 fixed to the bending portion 5 is narrowed, and when the bending portion 5 is bent to the target bending angle, the second coil pipe 14 becomes the first coil pipe. 13 abuts. At this time, when the user detects the touch when the second coil pipe 14 comes into contact with the first coil pipe 13, the user can recognize the state in which the bending portion 5 is bent to the target bending angle. it can.

  In the present embodiment, a stopper 19 that restricts the operating range of the operation lever 7 by abutting the lever 16 with the lever cam 20 of the drum 16 is provided inside the operation unit 3. Further, the stopper 19 is provided with an elongated hole 21 for changing the abutting position with the lever cam 20, and the stopper 19 is moved along the elongated hole 21 by loosening the fixing screw 22, so that the abutting position with the lever cam 20 is reached. The position is adjusted. When adjusting the position of the stopper 19, in addition to the stroke amount when there is no load, the position adjustment is performed with a margin for the amount of elongation when a specified tensile force within the elastic deformation range of the bending wire 12 is applied. Therefore, even when the operation lever 7 is operated with a full stroke, it is possible to prevent the bending wire 12 from being deformed and extended or torn.

  FIG. 4 shows a second embodiment of the present invention. In the present embodiment, the configuration of the bending portion 5 of the endoscope 1 according to the first embodiment (see FIGS. 1 to 3) is changed as follows.

  That is, in the present embodiment, instead of the second coil pipe 14 as the guide tube of the bending wire 12 of the first embodiment, it is exposed between the node ring 9a and the tip surface of the first coil pipe 13. A projection-shaped pipe member (stopper) 31 is brazed and fixed to the middle portion of the exposed portion of the bending wire 12. The other parts have the same configuration as the endoscope 1 of the first embodiment, and the same parts as those of the endoscope 1 of the first embodiment are denoted by the same reference numerals. Then, the explanation is omitted.

  The pipe member 31 is arranged at a position where an appropriate gap L is provided between the pipe member 31 and the first coil pipe 13 in a state where the bending portion 5 is straight. The gap L is set so as to regulate the operation stroke of the bending wire 12 when the bending portion 5 is bent. When the bending angle of the bending portion 5 reaches an appropriate setting angle of, for example, about 90 ° during the pulling operation of the bending wire 12, the pipe member 31 hits the tip end portion of the first coil pipe 13, so that the operator By the hand feeling when the pipe member 31 hits the end surface of the front end portion of the first coil pipe 13, it is possible to recognize the state in which the bending portion 5 is bent to the target bending angle.

  Next, the operation of the above configuration will be described. In the endoscope 1 according to the present embodiment, when the bending portion 5 of the insertion portion 2 is bent by rotating the operation lever 7 of the operation portion 3, the pipe member 31 corresponds to the pulling stroke amount of the bending wire 12. Moves closer to the first coil pipe 13. At this time, when the bending wire 12 is further pulled until the bending angle of the bending portion 5 reaches an appropriate setting angle of, for example, about 90 °, the pipe member 31 finally comes into contact with the end surface of the first coil pipe 13. Thereby, the operator can recognize the state in which the bending portion 5 is bent to the target bending angle by the hand feeling when the pipe member 31 hits the end surface of the first coil pipe 13. The amount of movement of the pipe member 31 is determined by the gap L, and the gap L becomes the pulling stroke of the bending portion 5 and generally restricts the bending angle.

  Therefore, in the endoscope 1 of the present embodiment, a protruding shape is formed in the middle of the exposed portion of the bending wire 12 instead of the second coil pipe 14 as the guide tube of the bending wire 12 of the first embodiment. Since the pipe member 31 is brazed and fixed, the bending portion 5 is fixed to the flexible tube portion 4 as the bending angle of the bending portion 5 increases when the bending lever 12 is pulled by rotating the operation lever 7 of the operation portion 3. When the gap L between the first coil pipe 13 and the pipe member 31 fixed to the bending wire 12 is narrowed and the bending portion 5 is bent to the target bending angle, the pipe member 31 is moved to the first coil. It contacts the pipe 13. At this time, when the user detects the touch when the pipe member 31 is in contact with the first coil pipe 13, the effect that the bending portion 5 can be recognized to be bent to the target bending angle can be recognized. is there.

  The present invention is not limited to the above embodiment. For example, the bending wire 12 uses a twisted wire obtained by twisting strands in a rope shape and then performing a drawing process or a continuous caulking process, and the guide tube of the bending wire 12 is composed of a multi-ply hollow cable coil. May be.

  In this modification, it is possible to minimize the elongation of the bending wire 12, and the amount of contraction of the flexible tube portion 4 is also improved, so that the phenomenon of bending over the bending wire 12 can be minimized. it can. For this reason, the endoscope 1 according to the present modification has a structure in which even when the load applied to the bending wire 12 fluctuates, the bending wire 12 does not easily change due to the load and the flexible tube portion 4 does not change. Therefore, regardless of whether or not the treatment instrument is inserted, there is an effect that the bending portion 5 can perform a bending operation to a target bending angle.

  Furthermore, it goes without saying that various modifications can be made without departing from the scope of the present invention.

Next, other characteristic technical matters of the present application are appended as follows.
Record
(Additional Item 1) The operation unit is coupled to the proximal end side of the insertion portion to be inserted into the body cavity, and a plurality of bending pieces are provided along the axial direction of the insertion portion on the distal end side of the insertion portion. A bending portion that is sequentially connected is provided, an insertion tube is provided behind the bending portion, a distal end of the bending wire is attached to the distal end side of the bending portion, and the flexible guide tube that is inserted into the proximal end side of the insertion portion is inserted into the flexible guide tube. In an endoscope in which a bending wire is inserted so as to be able to advance and retreat, and the bending wire is pulled by a pulling means provided in the operation portion, and the bending portion is bent, the first guide tube is connected to the bending portion. An internal tube that is fixed to the insertion tube outside the range, the second guide tube is fixed to the proximal end of the bending portion, and a gap is provided between the first guide tube and the second guide tube. mirror.

  (Additional Item 2) The operation unit is coupled to the proximal end side of the insertion portion to be inserted into the body cavity, and a plurality of bending pieces are provided along the axial direction of the insertion portion on the distal end side of the insertion portion. A bending portion that is sequentially connected is provided, an insertion tube is provided behind the bending portion, a distal end of a bending wire is attached to the distal end side of the bending portion, and the flexible guide tube that is inserted into the proximal end side of the insertion portion is inserted into the flexible guide tube. In an endoscope in which a bending wire is inserted so as to be able to advance and retreat, and the bending wire is pulled by a pulling means provided in the operation portion, and the bending portion is bent, the first guide tube is connected to the bending portion. An endoscope which is fixed to an insertion tube outside the range and is provided with a projection shape which abuts against the first guide end when the wire moves in the bending portion range.

  (Additional Item 3) The operation unit is coupled to the proximal end side of the insertion portion to be inserted into the body cavity, and a plurality of bending pieces are provided along the axial direction of the insertion portion on the distal end side of the insertion portion. A bending portion that is sequentially connected is provided, an insertion tube is provided behind the bending portion, a distal end of a bending wire is attached to the distal end side of the bending portion, and the flexible guide tube that is inserted into the proximal end side of the insertion portion is inserted into the flexible guide tube. In an endoscope in which a bending wire is inserted so as to be able to advance and retract, and the bending wire is pulled by a pulling means provided in the operation unit, and the bending portion of the wire is twisted in a rope shape. An endoscope characterized by using a wire that has been stretched or continuously crimped after being combined, and a guide tube using a multi-cable hollow cable coil.

  (Additional Item 4) As a structure for bending the insertion portion to be inserted into the body cavity, a bending operation lever provided in the operation portion, a drum for converting the operation force of the bending operation lever into a force for pulling the wire, and the drum and the bending portion With the wires arranged to fix each end face to the tip, a bending force is applied to the tip of the bending part via the wire in conjunction with the movement of the bending operation lever, and the insertion part is bent and bent. The endoscope according to any one of additional items 1 and 2, wherein a position of the stopper is adjusted by applying a predetermined pulling force within the elastic deformation range of the wire in order to regulate the lever operating range.

  The present invention is effective, for example, for an endoscope in which an endoscope is inserted into a body cavity and the bending portion at the distal end of the insertion portion is bent in the body cavity and a technical field for manufacturing the endoscope.

1 is an overall side view of an endoscope according to a first embodiment of the present invention. The longitudinal cross-sectional view which shows the internal structure of the curved part of the endoscope of 1st Embodiment. The longitudinal cross-sectional view which shows the internal structure of the operation part of the endoscope of 1st Embodiment. The longitudinal cross-sectional view which shows the internal structure of the bending part of the endoscope of the 2nd Embodiment of this invention.

Explanation of symbols

    DESCRIPTION OF SYMBOLS 1 ... Endoscope, 2 ... Insertion part, 3 ... Operation part, 4 ... Flexible pipe part, 5 ... Bending part, 9 ... Node ring (bending piece), 12 ... Bending wire, 16 ... Drum (traction means), 13 ... 1st coil pipe (1st guide pipe), 14 ... 2nd coil pipe (2nd guide pipe), L ... clearance gap.

Claims (4)

The operation unit is connected to the proximal end side of the insertion unit to be inserted into the body cavity,
The insertion portion includes an elongated flexible tube portion and a bending portion that is connected to a distal end portion of the flexible tube portion and can be deformed by bending.
The bending portion has a plurality of bending pieces sequentially connected along the axial direction of the insertion portion,
In an endoscope for bending the bending portion by attaching the distal end of the bending wire to the distal end side of the bending portion and pulling the bending wire by a pulling means provided in the operation portion.
Fixing the distal end portion of the flexible first guide tube, which is inserted through the bending wire so as to freely advance and retract, to the distal end portion of the flexible tube portion;
Fixing a distal end portion of a flexible second guide tube, which is inserted through the bending wire so as to freely advance and retract, to the distal end portion of the bending portion;
An endoscope characterized in that a gap is provided between the first guide tube and the second guide tube to regulate an operation stroke of the bending wire during a bending operation of the bending portion. The operation unit is connected to the proximal end side of the insertion unit to be inserted into the body cavity,
The insertion portion includes an elongated flexible tube portion and a bending portion that is connected to a distal end portion of the flexible tube portion and can be deformed by bending.
The bending portion has a plurality of bending pieces sequentially connected along the axial direction of the insertion portion,
In an endoscope for bending the bending portion by attaching the distal end of the bending wire to the distal end side of the bending portion and pulling the bending wire by a pulling means provided in the operation portion.
Fixing the distal end portion of the flexible first guide tube, which is inserted through the bending wire so as to freely advance and retract, to the distal end portion of the flexible tube portion;
Providing a midway part of the bending wire disposed in the bending part with a protrusion-shaped stopper that abuts against the distal end of the first guide tube during the pulling operation of the bending wire;
An endoscope characterized in that a gap is provided between the first guide tube and the stopper to regulate an operation stroke of the bending wire during a bending operation of the bending portion. The bending wire uses a twisted wire obtained by twisting strands into a rope shape and then performing a drawing process or a continuous caulking process,
The endoscope according to claim 1 or 2, wherein the guide tube uses a multi-row hollow cable coil. The pulling means includes a bending operation lever provided in the operation unit,
A drum in which a proximal end portion of the bending wire is fixed and an operation force of the bending operation lever is converted into a force for pulling the bending wire;
A bending mechanism that applies a pulling force to the distal end of the bending portion via the bending wire in conjunction with the movement of the bending operation lever, and bending the bending portion;
3. A position adjusting means for adjusting a position of a stopper by applying a predetermined pulling force within an elastic deformation range of the bending wire in order to regulate an operation range of the bending operation lever. The endoscope described.

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