JP2003319904A - Breaking preventer of flexible endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a breaking preventer of a flexible endoscope which prevents foul fluid from intruding between a distal end of the breaking preventer and the outer peripheral surface of a flexible tube and facilitates assembly and disassembly thereof to the flexible tube. <P>SOLUTION: The breaking preventer 3 of the flexible endoscope is arranged to encircle the part near the coupling end of the flexible tube 1 coupled to a rigid body section 2 of the endoscope, is formed into a cylindrical shape of the thickness gradually decreasing toward the distal end side with an elastic material and is attached to the flexible tube 1 in the state of tightening the tube in a segment near the distal end, in which a projecting part 30 extending to the entire circumference is formed on the outside surface side of the extreme distal end segment to make the extreme end segment greater in thickness than the adjacent parts. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible inner tube for preventing a flexible tube of an endoscope from sharply bending near a connection end with a rigid body. Related to breaking endoscopes. 2. Description of the Related Art A flexible tube of an endoscope is connected to a rigid body such as an operation unit, and the vicinity of the connection end thereof is far smaller than other parts when bent with a small radius of curvature. A buckle made of a resilient material is attached so that it can easily buckle. [0003] Such a flexible endoscope is generally formed of a resilient material into a cylindrical shape whose thickness gradually decreases toward the distal end, and is connected to a rigid body of the endoscope. It is arranged so as to surround the vicinity of the connection end of the flexible tube, and is attached in a state where the flexible tube is fastened at the distal end portion. [0004] If the tip of the buckle is too tightly fastened to the flexible tube, it becomes difficult to mount the buckle on the flexible tube. Conventionally, however, the flexible tube was lightly tightened at the distal end of the buckle. However, when the flexible tube was bent, a gap was formed between the distal end of the buckle and the flexible tube. In some cases, waste may enter the gaps and become dirty. Therefore, as a countermeasure, for example,
As shown in JP-A-3-241, there is a case where the inner peripheral surface of the buckle is joined to the surface of the flexible tube, but in this case the buckle cannot be disassembled with respect to the flexible tube. Would. Accordingly, the present invention is directed to a flexible endoscope which is free of contaminants between the tip of the buckle and the outer peripheral surface of the flexible tube and which can be easily assembled and disassembled with the flexible tube. The purpose is to provide. [0008] In order to achieve the above-mentioned object, a flexible endoscope according to the present invention is provided with a connecting end of a flexible tube connected to a rigid portion of the endoscope. It is arranged so as to surround the vicinity, is formed into a cylindrical shape having a thickness gradually reduced toward the distal end side by an elastic material, and is attached to a flexible tube attached in a state where the flexible tube is fastened at a portion near the distal end. In preventing the endoscope from being broken, a projecting portion is formed over the entire periphery on the outer surface side of the distal end portion, and the distal end portion is formed thicker than the adjacent portion. Embodiments of the present invention will be described with reference to the drawings. FIG. 2 shows an endoscope in which an insertion portion to be inserted into a body cavity is covered with a flexible tube 1, and a base end thereof is connected to an operation portion 2. The connector 5 connected to the light source device and the operation unit 2 are connected by the connection flexible tube 4. The connecting end portion of the flexible insertion tube 1 to the rigid operating portion 2, the connecting end portion of the flexible connecting tube 4 to the operating portion 2, and the connection of the flexible connecting tube 4 to a rigid connector 5. Bends 3, 6 for restricting the flexible tubes 1, 4 from bending with a small radius of curvature are attached to the end portions, respectively. FIG. 1 shows a connecting portion between the insertion portion flexible tube 1 and the operation portion 2, and illustrations of optical fiber bundles, tubes, signal cables, and the like inserted therein are omitted. I have. A flexible tube base end cap 11 fixed to the base end of the insertion portion flexible tube 1 is fixed to a frame of the operation unit 2 by a holding screw 12. The buckle 3 is formed in a tapered cylindrical shape with an elastic rubber-based material (for example, nitrile rubber, chloroprene rubber, polyurethane rubber or the like having a JIS rubber hardness of about 40 to 65 °). Flexible insertion tube 1
And a metal attachment base 31 is integrally fixed to the base end thereof. A female screw portion formed on the inner surface of the mounting base 31 is screwed with a male screw portion formed at the end of the frame of the operating portion 2, whereby the base end of the buckle 3 is connected to the operating portion. 2 is fixed to the end. The buckling stopper 3 is formed in a tapered cylindrical shape in which both the inner and outer surfaces are gradually reduced in diameter toward the front side and the thickness is gradually reduced toward the front side. Is formed to have a diameter slightly smaller than the outer diameter of the insertion portion flexible tube 1. Therefore, the buckling stopper 3 is attached in a state in which the insertion portion flexible tube 1 is elastically fastened by being elastically deformed in a state of being wider than the natural state in the vicinity of the distal end. The chain double-dashed line indicates the shape of the buckle 3 itself in its natural state. As shown in FIG. 3, which is an enlarged view of the vicinity of the tip of the buckle 3, a projection 30 is formed over the entire circumference on the outer surface of the foremost portion of the buckle 3. Thereby, the thickness e2 of the foremost portion is formed to be thicker than the thickness e1 of the adjacent portion. FIG. 4 shows a state in which the vicinity of the connecting portion of the flexible tube 1 with respect to the operating portion 2 is bent with a radius of curvature of, for example, about 120 mm. The portion closer to the front end is greatly stretched as schematically indicated by arrow A, and the side located on the inner surface is more greatly compressed toward the front end as schematically indicated by arrow B. As a result, on the outer surface side of the curve at the foremost portion of the buckle 3, a force acts to peel the insertion tube 1 from the surface of the flexible tube 1. Since the thickness is small, the amount of elastic deformation is small, so that no gap is generated between the surface of the insertion portion flexible tube 1 and the distal end portion of the buckle 3 and the outer peripheral surface of the insertion portion flexible tube 1. Sewage does not enter between. Since the foremost portion of the buckle 3 has the above-described configuration and characteristics, the amount of tightening of the foremost portion of the buckle 3 with respect to the flexible tube 1 can be set small. is there. More specifically, the buckling stopper 3 is inserted into the flexible tube 1 of the insertion portion.
Even when the radial elongation rate of the foremost portion in the mounted state with respect to the natural state not mounted on the flexible tube 1 is set to a very small value of about 3 to 8%, the bending of the distal end portion with the surface of the insertion portion flexible tube 1 at the time of bending. There is no gap between them. If the amount of tightening of the foremost end of the buckle 3 with respect to the flexible tube 1 is set small, the assembling and disassembly of the buckle 3 with respect to the flexible tube 1 can be easily performed, and at the same time, with time. The occurrence of cracks at the tip of the buckle 3 due to the change is also suppressed. The present invention is not limited to the above embodiment. For example, as shown in FIG. 5, the cross-sectional shape of the projection 30 may be circular, as shown in FIGS. 6 and 7. 3a adjacent to the protrusion 30 of the buckle 3
May be formed to be thin so as to be stepped compared to a portion closer to the base end. The present invention can also be applied to the bending stopper 6 on the connecting flexible tube 4 side. According to the present invention, a protrusion is formed over the entire periphery on the outer surface side of the foremost part of the buckle, and the foremost part is formed thicker than the adjacent part. Since the adhesiveness to the outer peripheral surface of the flexible tube is enhanced, no waste liquid enters between the front end portion of the buckle and the outer peripheral surface of the flexible tube, and the amount of fastening to the flexible tube can be reduced. ,
The assembling and disassembly of the flexible tube are facilitated, and at the same time, the occurrence of cracks at the tip portion of the buckling prevention due to aging is suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a flexible endoscope according to a first embodiment of the present invention. FIG. 2 is an external view of an endoscope according to the first embodiment of the present invention. FIG. 3 is an enlarged cross-sectional view of a tip end portion of the flexible endoscope according to the first embodiment of the present invention. FIG. 4 is a vertical cross-sectional view of the flexible endoscope according to the first embodiment of the present invention in a state where the buckle is bent. FIG. 5 is an enlarged sectional view of a tip portion of a buckle of a flexible endoscope according to a second embodiment of the present invention. FIG. 6 is an enlarged sectional view of a tip portion of a buckle of a flexible endoscope according to a third embodiment of the present invention. FIG. 7 is an enlarged sectional view of a tip portion of a buckle of a flexible endoscope according to a fourth embodiment of the present invention. [Description of Signs] 1 Insertion part flexible tube 2 Operation part (rigid part) 3, 6 Bend prevention 4 Connecting flexible tube 5 Connector (rigid part) 30 Projecting part 3a Adjacent part

Claims (1)

Claims: 1. A flexible tube connected to a rigid portion of an endoscope is disposed so as to surround a vicinity of a connection end thereof. The flexible endoscope, which is formed in a cylindrical shape and is attached to the flexible tube at a position near the distal end in a state where the flexible tube is fastened, forms a protruding portion extending over the entire circumference on the outer surface side of the foremost portion. The flexible endoscope is characterized in that the tip portion is formed thicker than the adjacent portion.