JP4360834B2 - Endoscope curvature - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bending portion of an endoscope.
[0002]
[Prior art]
In general, the bending portion of an endoscope is configured such that adjacent node rings of a plurality of node rings arranged on a coaxial line are rotatably connected by a pair of rotation fulcrums arranged at 180 ° symmetrical positions around the axis. The operation wire is arranged along the inner surface of the node ring in a direction parallel to the axis of the node ring.
[0003]
Conventionally, the operation wire of the bending portion of the endoscope has been arranged at the center position between the pair of rotation fulcrums and the rotation fulcrum. In many cases, it is arranged at a position deviated from the center position with respect to the rotation fulcrum (for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 5-38325, FIG. 2, etc.
[Problems to be solved by the invention]
In the bending portion of the conventional endoscope as described above, the shape of the edge portion of the node ring is formed in a bilaterally symmetric shape with the positions of the rotation fulcrum at the left and right ends.
[0006]
Therefore, when the node ring is rotated around the rotation fulcrum until the edges of the adjacent node rings come into contact with each other by the bending operation, the edges of the adjacent node rings are paired with the rotation fulcrum and the rotation fulcrum. Abuts at the center position.
[0007]
Then, when the operation wire is in a position deviated from the center position of the pair of rotation fulcrum and the rotation fulcrum, a built-in object such as an optical fiber bundle inserted inside is adjacent to the node ring. Since they are in direct contact with each other, they may be sandwiched between the node rings and damaged.
[0008]
Therefore, the present invention provides a bending portion of an endoscope in which an operation wire is disposed at a position deviated from a center position between a pair of rotation fulcrums and a rotation fulcrum. An object of the present invention is to provide a bending portion of an endoscope having excellent durability that is not pinched and damaged.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the bending portion of the endoscope of the present invention includes a pair of adjacent node rings of a plurality of node rings arranged on the same axis arranged in a 180 ° symmetrical position around the axis. The operation wires are connected to each other at the rotation fulcrum so that the operation wire is displaced from the center position of the pair of rotation fulcrum and the rotation fulcrum along the inner surface of the node ring in a direction parallel to the axis of the node ring. In the bending portion of the endoscope arranged in a manner, the shape of the edge of the node ring is such that the portion located outside the operation wire abuts when the adjacent node rings rotate around the rotation fulcrum Is formed.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 3 shows an overall configuration of the endoscope. A distal end body 3 in which a bending portion 2 bent by remote operation is connected to the distal end of the insertion portion flexible tube 1 and an observation window and an illumination window are arranged. Is connected to the tip of the bending portion 2.
[0011]
The operation unit 4 is connected to the proximal end of the insertion portion flexible tube 1, and by operating the bending operation member 5 disposed in the operation unit 4, one of the pair of operation wires 6 is pulled and the other is The bent portion 2 is bent and bent as indicated by a two-dot chain line.
[0012]
FIG. 4 shows the distal end portion of the bending portion 2. The bending portion 2 includes a plurality of (for example, about 10 to 20) node rings 21, 22, 23, 24... Arranged on a coaxial line, and the adjacent node rings 21, 22, 23, 24. Are connected to each other by a pair of connecting shafts 25 (rotating fulcrums) arranged at 180 ° symmetrical positions, and the periphery thereof is covered with a rubber tube outer skin.
[0013]
As the node rings 21, 22, 23, 24..., The state-of-the-art node ring 21 connected to the tip body 3 and the operation wire 6 are used in addition to the most commonly used standard node rings 22 and 23. Several types of node rings 21 such as a guided node ring 24 in which a wire guide 27 to be guided inwardly projects, and a node ring (not shown) at the end connected to the insertion portion flexible tube 1. , 22, 23, 24... Are combined and connected.
[0014]
In the bending portion 2, as shown in FIG. 5 illustrating a VV cross section, a signal cable 7 for transmitting an imaging signal of an endoscope observation image, a light guide fiber bundle 8 for illumination, a treatment instrument insertion channel Various built-in items such as 9 are inserted. In FIG. 4, illustration of built-in objects is omitted.
[0015]
The position of each of the pair of operation wires 6 is regulated by the wire guide 27, and the center position between the pair of connecting shafts 25 and 25 so that the built-in objects 7, 8, and 9 can pass smoothly. Rather than the pair of connecting shafts 25 and the center position of the connecting shaft 25, the nodal rings 21, 22, 23, 24. It is arranged along the inner surface.
[0016]
Each of the pair of operation wires 6 is disposed so as to be able to advance and retract in the axial direction over the entire length, and the distal ends of the operation wires 6 are fixed to the distal end portion body 3. Reference numeral 29 shown in FIG. 4 is a known fixing ring for this purpose.
[0017]
FIG. 2 shows the node rings 22 and 23 as a single unit, and a pair of tongue pieces A and B project from each of the front and rear portions of the node rings 22 and 23 at positions 180 degrees symmetrical, Holes a and b for passing through the connecting shaft 25 are formed in the tongue pieces A and B, respectively. Further, each edge of each node ring 22, 23 is formed in a stepped portion where the operation wire 6 is disposed inside (stepped portion C).
[0018]
Accordingly, by overlapping the tongue pieces B and A of the adjacent node rings 22 and 23 and passing the connecting shaft 25 through the holes b and a, as shown in FIG. The bending portion 2 is bent as a whole by relatively rotating around the connecting shaft 25.
[0019]
As described above, when one of the pair of operation wires 6 is pulled by the bending operation and the other is loosened, and the node rings 22 and 23 are rotated around the connecting shaft 25 to the maximum extent, FIG. As shown in FIG. 4, the edges of the adjacent node rings 22 and 23 come into contact with each other, and the node rings 22 and 23 come into contact with each other at the stepped portion C formed at the edge.
[0020]
Then, since the operation wire 6 is disposed inside the contact portion between the edge portions of the node rings 22 and 23, the built-in objects 7, 8, and 9 are not sandwiched between the contact portions, and are curved. Even if the operation is repeated, the built-in items 7, 8, and 9 are not damaged.
[0021]
The present invention is not limited to the above embodiment. For example, the bending portion 2 of the above embodiment bends only in two directions that are 180 ° symmetrical, but the present invention bends in four directions, that is, up, down, left, and right. It can also be applied to a four-way bending portion. Moreover, the structure etc. which make a rotation fulcrum by engaging a hook etc. without using the connecting shaft 25 for a rotation fulcrum may be used.
[0022]
【The invention's effect】
According to the present invention, in the bending portion of the endoscope in which the operation wire is disposed at a position deviated from the center position between the pair of rotation fulcrum and the rotation fulcrum, the shape of the edge of the node ring is adjacent. Each node ring is rotated when the node ring is rotated to the maximum by forming a shape in which the portions located outside the operation wire come into contact with each other when the node rings rotate around the rotation fulcrum. An operation wire is arranged inside the contact part between the two parts, so that the built-in object is not sandwiched between the node rings, so that the built-in object is not damaged even if the bending operation is repeated. Excellent durability can be obtained.
[Brief description of the drawings]
FIG. 1 is a partially exploded perspective view of a bending portion according to an embodiment of the present invention.
FIG. 2 is a perspective view showing a node ring of a bending portion according to an embodiment of the present invention alone.
FIG. 3 is a side view showing an overall configuration of an endoscope according to an embodiment of the present invention.
FIG. 4 is a side sectional view of the vicinity of the distal end of the bending portion according to the embodiment of the present invention.
5 is a cross-sectional view taken along the line VV in FIG. 4 of the bending portion according to the embodiment of the present invention.
[Explanation of symbols]
2 Bending portion 6 Operation wires 21, 22, 23, 24 Node ring 25 Connecting shaft (rotating fulcrum)
7, 8, 9 Built-in object C Stepped portion

Claims (1)

Adjacent node rings of a plurality of node rings arranged on the coaxial line are rotatably connected by a pair of rotation fulcrums arranged at 180 ° symmetrical positions around the axis, and the operation wires are connected to the pair In the bending portion of the endoscope arranged along the inner surface of the node ring in a direction parallel to the axis of the node ring at a position deviated from the center position of the rotation fulcrum and the rotation fulcrum,
The shape of the edge of the node ring is formed such that when the adjacent node rings rotate around the rotation fulcrum, the portion located outside the operation wire abuts. The bending part of the endoscope.

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