JP2537612Y2 - Flexible tube of endoscope - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible tube for an endoscope which forms an endoscope insertion portion and the like.

[0002]

2. Description of the Related Art A flexible tube of an endoscope, whose hardness is changed in the middle thereof, is often used so that it can be inserted into a body cavity or the like as easily as possible.

In order to change the hardness of the flexible tube in the middle, various structures have been conventionally devised. In recent years, however, a plurality of synthetic resin tubes having the same radial size and different hardness have been developed. In many cases, the end surfaces are brought into contact with each other, and a synthetic resin of the same type as the tube is heated and welded to the contact surfaces.

[0004]

[Problems to be solved by the invention] However, in a structure in which the end faces of the tubes are simply brought into contact with each other and welded, the welded area is small, so that the welded portion is peeled off by repeated bending or the like, so that sufficient strength is not necessarily obtained. I can't get it.

[0005] In particular, when the flexible tube is bent, the soft tube is bent with an extremely small radius of curvature near the joint, so that a load is applied to the joint and not only peeling but also wrinkles are generated. .

Accordingly, the present invention provides an endoscope having a plurality of tubes made of synthetic resin, which are provided with end faces in contact with each other and connected in the axial direction of the tube, and which have excellent durability against repeated bending and the like. An object of the present invention is to provide a flexible tube.

[0007]

In order to achieve the above object, a flexible tube of an endoscope according to the present invention comprises a plurality of tubes made of a flexible synthetic resin having substantially the same radial dimension. In a flexible tube of an endoscope, which is abutted with each other and joined in the tube axis direction, the outer peripheral surface of the flexible tube of the endoscope astride an annular groove having a depth smaller than the thickness of the adjacent tube at the joint portion. And a synthetic resin similar to the tubes is filled in the annular groove and welded.

[0008]

An embodiment will be described with reference to the drawings.

FIG. 2 shows an endoscope. An elongated insertion section 1 is connected to a distal end of a flexible tube 2 by a remote control, and is provided with an observation window, an illumination window, and the like. The distal end main body 4 is connected to the distal end of the bending portion 3.

The operation unit 5 is provided with a bending operation device 51, an air / water supply / suction operation device 52, and the like, and the eyepiece unit 6 is also protruded from the operation unit 5. Further, a light guide connector 7 connected to the light source device is connected to the operation unit 5 by a connection flexible tube 8.

FIG. 1 is a cross-sectional view of a flexible tube 2 constituting an insertion portion 1, and a so-called built-in component such as an optical fiber bundle inserted therein is omitted.

Reference numeral 21 denotes a spiral tube formed by spirally winding a stainless steel strip, a phosphor bronze strip, or the like at a constant pitch to the same diameter. In this figure, the spiral tube 21 has a single layer, but a plurality of spiral tubes having different winding directions may be superposed two or more times.

The outer surface of the spiral tube 21 is covered with a mesh tube 22 formed by knitting a fine stainless steel wire or the like in a net shape. Then, on the outer surface of the mesh tube 22, first and second tubes 23 made of, for example, polyurethane resin are used.
24 are coated.

The first and second tubes 23 and 24 have the same dimensions such as diameter and wall thickness, and are both flexible. The second tube 24 that covers the proximal end side of the insertion portion 1
More flexible and bendable materials are used. The arrangement of the first and second tubes 23, 24 is also shown in FIG.

The first and second tubes 23 and 24 cover the flexible tube 2 in a state where the end surfaces thereof come into contact with each other and are joined in the tube axis direction. Second
Over each of the tubes 23, 24,
An annular groove 25 having a depth of about half the thickness of the 24 and a width of, for example, about 2 to 2.5 mm is formed on the outer peripheral surface.

A polyurethane resin 26 similar to the first and second tubes 23 and 24 is provided in the annular groove 25.
And heat-welded. Therefore, welding can be performed in a larger area than the end surfaces of the tubes 23 and 24, and since the resins are of the same system, they are strongly welded to each other. In addition, you may weld with a solvent etc.

Also, the first and second tubes 23, 24
Is fixed in a state similar to that which is fastened with a band from the outside by the welding resin 26 at the ends, so that even if this part is repeatedly bent, the ends of the first and second tubes 23 and 24 are fixed. Without peeling off from the surface of the reticulated tube 22,
Also, no wrinkles are generated on the tubes 23 and 24.

Further, the hardness of the welding resin 26 is determined by the first and second hardnesses.
When the hardness of the tubes 23 and 24 is about the middle, the change in hardness at the connection portion becomes smooth, so that a so-called anti-bending effect is obtained, and the first tube 23 suddenly has a small radius of curvature. This prevents the occurrence of a state of bending.

The present invention is not limited to the above embodiment, but may be applied to, for example, the first and second tubes having the same hardness. In addition, the present invention may be applied to the connecting flexible tube 8 or the like.

[0020]

According to the flexible tube of the endoscope of the present invention, the strength of the joint portion of the plurality of tubes is greatly enhanced, the durability is improved, and the structure therefor is very simple and the cost is low. It has an excellent effect that is not applied.

[Brief description of the drawings]

FIG. 1 is a half sectional side view of a flexible tube according to an embodiment.

FIG. 2 is an overall schematic diagram of the endoscope of the embodiment.

[Explanation of symbols]

 23 first tube 24 second tube 25 annular groove 26 polyurethane resin (welding resin)

Claims (1)

(57) [Scope of request for utility model registration] 1. A flexible tube of an endoscope comprising a plurality of flexible synthetic resin tubes having substantially the same radial dimension and externally attached by connecting end surfaces thereof in a tube axial direction. In the joint portion, an annular groove having a depth shallower than the thickness of the adjacent tube is formed on the outer peripheral surface across the tubes on both sides, and a synthetic resin similar to those tubes is filled in the annular groove and welded. A flexible tube for an endoscope.