JP2005261513A - Insertion part of flexible endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an insertion part of a flexible endoscope capable of obtaining excellent insertability by constituting the second half part of a curved part into a second curved part to be freely bent with small external force while securing the minimum firmness without hardening the elastic jacket of the curved part. <P>SOLUTION: The tip of a tight winding coil pipe 26 to be a guide of an operation wire 24 is arranged so as to abut from the rear part when the curved parts 2A and 2B are in a straight state without being fixed to a wire guide 25A projecting inwards from a joint ring 21A at the middle position of the curved parts 2A and 2B. The part in the middle of the tight winding coil pipe 26 is fixed near the boundary part of a flexible pipe 1 and the curved parts 2A and 2B. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an insertion portion of a flexible endoscope.

  In general, the insertion portion of the flexible endoscope is a plurality of rotatably connected to the distal end of the flexible tube formed by covering the outer surface of the coarsely wound metal spiral tube with the flexible skin. The bending portion formed by covering the outer surface of the node ring with a flexible outer skin is connected, and the distal end of the operation wire that is advanced and retracted from the proximal end side of the flexible tube is connected to the vicinity of the distal end of the bending portion. It has become.

  The insertion portion of the flexible endoscope having such a configuration can bend the bending portion in a desired direction according to the shape of the organ in the body cavity, but near the connection portion between the bending portion and the flexible tube. However, it is difficult to avoid that the structure is hard to some extent, and the flexible outer skin covering the flexible tube is harder than the elastic outer skin covering the curved portion.

  Therefore, as shown in FIG. 5, even if the flexible tube 1 is pushed in from the proximal side in a state where the bending portion 2 is bent for insertion into the inside of the body, the flexible tube adjacent to the rear end of the bending portion 2 There are cases where the vicinity of the tip of 1 is stretched and cannot be inserted smoothly.

Therefore, conventionally, the tip of the tightly wound coil pipe that serves as a guide for the operation wire is fixed to the middle position of the bending portion, and the latter half of the bending portion behind the position is lightened by external force without receiving bending operation by the operation wire. It was made to bend freely (for example, patent document 1).
Reality 1-222641

  When the configuration described in Patent Document 1 described above is adopted, a phenomenon in which the latter half portion of the bending portion becomes a so-called second bending portion having a characteristic of being freely bent with a very small external force, and that portion is stretched during insertion. Can be avoided.

  However, the second curved portion having such a configuration is too soft and weak, and even if there is a slight catch in the body during insertion, the second curved portion will oscillate without maintaining linearity, and the insertability will be reduced. There is a case.

  Therefore, if the elastic skin covering the curved portion is hardened, such fluctuation can be suppressed, but if this is done, the operation for bending the curved portion becomes heavy and the operability is reduced. At the same time, there is a drawback that the durability of the operation wire is lowered.

  Therefore, the present invention is configured by forming the second half of the bending portion into a second bending portion that can be bent freely with a small external force while ensuring the minimum waist strength without hardening the elastic skin of the bending portion. An object of the present invention is to provide an insertion portion of a flexible endoscope that can obtain excellent insertion properties.

  In order to achieve the above object, the insertion portion of the flexible endoscope of the present invention is relatively positioned at the distal end of the flexible tube having a structure in which the outer surface of the coarsely wound metal spiral tube is covered with the flexible skin. A curved portion configured to cover a resilient outer skin is connected to the outer surface of a plurality of joint rings that are rotatably connected. The curved portion is inserted from the inside of the flexible tube to the inside of the curved portion, and is advanced and retracted from the proximal end side of the flexible tube. In the insertion portion of the flexible endoscope in which the distal end of the operation wire connected to the vicinity of the distal end of the bending portion, the distal end of the tightly wound coil pipe that serves as a guide for the operation wire is moved from the node ring in the middle of the bending portion. It is arranged so that it comes into contact with the wire guide protruding inward from behind when the bending portion is straight without being fixed, and the middle part of the closely wound coil pipe is bent with the flexible tube. It is fixed in the vicinity of the boundary with the part.

  According to the present invention, the bending portion is straight without fixing the tip of the closely wound coil pipe that serves as a guide for the operation wire to the wire guide that protrudes inward from the node ring in the middle of the bending portion. In such a state, it is arranged so as to come into contact with the rear side, and by fixing the middle part of the tightly wound coil pipe near the boundary between the flexible tube and the bending portion, the elastic outer skin of the bending portion is hardened. Instead, the second half of the bending portion can be configured as a second bending portion that can be bent freely with a small external force while ensuring a minimum waist strength, and thus excellent insertability can be obtained.

  The structure is such that the outer surface of a roughly wound metal ring is covered with a flexible outer cover, and the outer surface of a plurality of joint rings connected relatively freely to the tip of the flexible tube is covered with a flexible outer cover. A flexible endoscope in which a distal end of an operation wire that is connected to a bending portion and is inserted and arranged from the inside of the flexible tube to be advanced and retracted from the proximal end side of the flexible tube is connected to the vicinity of the distal end of the bending portion. In the insertion portion, the bending portion is straight without fixing the tip of the tightly wound coil pipe that serves as a guide for the operation wire to the wire guide protruding inward from the node ring in the middle of the bending portion. It arrange | positions so that it may contact | abut from back at the time of a state, and the part in the middle of a tightly wound coil pipe is fixed to the boundary part vicinity of a flexible tube and a curved part.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 2 shows a flexible endoscope, and an insertion portion to be inserted into the body includes a first bending portion 2A in the front half and a second bending in the rear half at the distal end of the flexible tube 1. The bending part which consists of the part 2B is connected, and it has the structure which the front-end | tip part main body 3 was connected to the most advanced part.

  The operation section 4 connected to the base end of the flexible tube 1 is provided with a bending operation knob 5 that can bend the first bending section 2A in an arbitrary direction by an arbitrary angle by remote operation. An alternate long and two short dashes line indicates a state where the first bending portion 2A is slightly bent. The second bending portion 2B is not bent by remote operation.

  FIG. 1 shows the vicinity of the distal end of the insertion portion. The flexible tube 1 is formed by arranging, for example, a metal spiral tube 11 formed by roughly winding a stainless steel strip in a single, double or triple manner, and on the outer surface thereof. For example, a flexible outer skin 12 made of a polyurethane resin tube or the like is covered. Between the metal spiral tube 11 and the flexible sheath 12, a mesh tube formed by braiding stainless steel fine wires or the like is disposed.

  The first bending portion 2A in the front half of the bending portion and the second bending portion 2B in the rear half have a plurality of (for example, about 5 to 20) node rings 21 that are relatively moved by rivets 22 or the like. The outer surface is covered with a resilient outer shell 23 made of rubber tube. Between the node ring 21 and the elastic outer skin 23, a mesh tube formed by braiding a metal or non-metallic fine wire is disposed.

  Each node ring 21 is connected to the adjacent node ring 21 by a pair of rivets 22 in a 180 ° symmetrical position. Therefore, the bent portion in the up and down direction and the bent portion in the left and right direction are alternately combined, so that it can be bent in any direction of 360 ° as a whole.

  The distal end portions of the first bending portion 2A are connected to the distal end portions of the four operation wires 24 inserted and arranged from the inside of the flexible tube 1 into the bending portion at approximately 90 ° intervals. , Each operation wire 24 is inserted into a wire guide 25 projecting inwardly from the inner peripheral surface of each node ring 21 so as to be movable forward and backward in the axial direction. As a result, when the operation wire 24 is pulled from the operation unit 4 side, the first bending portion 2A bends in the direction of the pulled operation wire 24.

  In the second bending portion 2B and the flexible tube 1, each operation wire 24 is inserted and guided in a coil pipe 26 tightly wound with a stainless steel wire so as to advance and retreat in the axial direction. The base end portion is fixed to the operation portion 4 through the flexible tube 1 over the entire length.

  The wire guide 25 is not provided in the second bending portion 2B, and each of the four coil pipes 26 has a distal end node at the end of the first bending portion 2A when the bending portions 2A and 2B are straight. It arrange | positions in the state contact | abutted from the back to the wire guide 25A projected inwardly from the ring | wheel 21A. In addition, the front-end | tip part of each coil pipe 26 is not being fixed anywhere.

  Then, on the inner peripheral surface of the distal end cap 13 of the flexible tube 1 that is screwed to the rear end of the second bending portion 2B, intermediate portions of the coil pipes 26 are spaced at approximately 90 ° intervals by brazing 30 or the like. It is fixed.

  As described above, the second curved portion 2B having a structure in which the outer surface of the plurality of node rings 21 that are relatively rotatably connected by the rivet 22 is covered with the flexible elastic outer shell 23 is freely bent by a small external force. It has the characteristic to do.

  And with such a configuration alone, the second bending portion 2B becomes too flexible and the waist becomes weak unless the elastic shell 23 is hardened, but the four coil pipes 26 are arranged at intervals of approximately 90 °. 2. By placing it in a state of stretching in the curved portion 2B, the elastic outer shell 23 is not hardened, and the waist strength is secured so that it does not shake even if there is a slight catch during insertion into the body. doing.

  3 and 4 schematically show a state in which the insertion portion of the flexible endoscope of the above-described embodiment is inserted into the body. As shown in FIG. 3, the bent first bending portion 2A is shown in FIG. When the flexible tube 1 is pushed in from the proximal side after hitting the body wall, the second bending portion 2B is not bent and stretched by the pushing force as shown in FIG. The body part 3 can be pushed forward.

  When the second bending portion 2B is bent as described above, the coil pipe 26a located at the inner side of the bending curve meanders in a state of stretching in the second bending portion 2B and acts as an appropriate resistance against bending. The coil pipe 26b on the outer side of the slidable portion moves in accordance with the deformation of the second bending portion 2B in a free state because the distal end side is not fixed.

It is side surface sectional drawing of the vicinity of the front-end | tip of the insertion part of the flexible endoscope of the Example of this invention. It is a side view showing the whole flexible endoscope composition of the example of the present invention. It is a schematic diagram showing the state where the flexible endoscope of the example of the present invention is inserted into the body. It is a schematic diagram showing the state where the flexible endoscope of the example of the present invention is inserted into the body. It is a schematic diagram which shows the insertion state in the body of the conventional flexible endoscope.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Flexible tube 2A 1st bending part 2B 2nd bending part 4 Operation part 11 Metal spiral tube 12 Flexible outer skin 13 Tip cap 21, 21A Node ring 22 Rivet 23 Elastic outer skin 24 Operation wire 25, 25A Wire guide 26 Coil Pipe 30 with brazing

Claims (1)

The structure is such that the outer surface of a roughly wound metal ring is covered with a flexible outer cover, and the outer surface of a plurality of joint rings connected relatively freely to the tip of the flexible tube is covered with a flexible outer cover. A bending portion is connected, and a distal end of an operation wire that is inserted and arranged from the inside of the flexible tube to the inside of the bending portion and is advanced and retracted from the proximal end side of the flexible tube is connected to the vicinity of the distal end of the bending portion. In the insertion part of the sex endoscope,
The tip of the tightly wound coil pipe that serves as a guide for the operation wire is not fixed to the wire guide that protrudes inward from the node ring in the middle of the bending portion, and the bending portion is straight. The flexible endoscope according to the present invention, wherein the flexible endoscope is arranged so as to come into contact with the back from time to time, and an intermediate portion of the tightly wound coil pipe is fixed in the vicinity of a boundary portion between the flexible tube and the curved portion. Insertion section.

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