JPH0143041Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an endoscope with improved insertion properties for treatment instruments.

Generally, an endoscope consists of a flexible tube through which a treatment instrument a such as forceps is inserted and guided to a channel opening c formed in a distal end portion b, as shown in Fig. 1. A channel tube d is connected to the channel opening c via a fixed pipe e. However, according to such a conventional structure, when the endoscope has a strongly curved or curled distal end as shown in the figure, when the distal end a' of the endoscope is inserted, Because the area near the opening edge of the fixed pipe e strongly hits the inner surface of the channel tube d, this part bulges outward and the tip a' of the treatment instrument a gets caught on the opening edge of the fixed pipe e, causing further damage. There were cases where it became impossible to insert the treatment instrument a. If the treatment instrument a is forcibly pushed in in this state, there is a risk that the channel tube d may be damaged or the distal end a' of the treatment instrument a may suddenly jump out of the channel opening c and damage the body cavity wall. Therefore, the procedure is usually to loosen the curve of the endoscope, insert the treatment tool a, and then curve it again. However, such a bending operation is complicated and time-consuming, and it takes a long time for endoscopy. This caused the process to take time.

This idea was made based on the above circumstances,
The purpose of this is to prevent the tip of the treatment instrument from getting caught in the fixed pipe even if the connection part of the channel tube with the fixed pipe is strongly curved, so that the insertion of the treatment instrument can be performed smoothly. Our goal is to provide endoscopes with improved performance.

An embodiment of the present invention will be described below with reference to FIGS. 2 to 4. In the figure, 1 is an insertion section of an endoscope. In this insertion section 1, a curved section 3 and a distal end forming section 4 are successively formed on the distal end side of a flexible section 2, and an operating section 5 is provided at the rear end. The curved section 3 rotatably connects a plurality of curved pieces 6 by a shaft 7,
The outside of the curved piece 6 is sequentially covered with a metal mesh pipe 8 and a rubber tube 9, and the most advanced curved piece 6
The main body 4a of the tip component 4 is attached to. An operation wire (not shown) is connected to the most advanced curved piece 6 to which the main body 4a is attached.
By pushing and pulling this operating wire with an operating knob 10 provided on the operating section 5, the bending section 3 can be bent.

A light guide 11 and an image guide 12 made of an optical fiber bundle are inserted into the insertion section 1, and a channel tube 14 forming a channel 13 is also inserted therethrough. The light guide 11 is held so that its tip faces the tip surface of the main body 4a of the tip structure section 4, and its rear end is inserted into a light guide cable 15 connected to a light source (not shown) connected to the operation section 5. ing. Further, the image guide 12 has its front end facing an imaging optical system 16 provided on the main body 4a, and its rear end facing an optical system 18 of an eyepiece section 17 formed on the operating section 5. Further, the channel tube 14 has a channel opening 1 bored at the tip in the main body 4a.
9 via a fixed pipe 20, and its rear end communicates with a forceps port 21 provided in the operating section 5. The channel tube 14 is made by stretching a crystalline polymer material, such as polytetrafluoroethylene, which has a porous structure in which a large number of microcrystal nodes are connected to each other by fine fibers. The distal end portion connected to is formed into a solid portion 22 that is solid and non-porous and is harder than other portions. In order to make the tip part of the channel tube 14 into a hard part 22, it is possible to leave this part unstretched from the beginning, or to make it porous and then heat and melt it to return it to a solid and non-porous state. can be done. The hard part 22 is formed in the channel tube 14 with a length of about 1/2 to several times the inner diameter.
is fitted onto the outer periphery of the fixed pipe 20 so that a part of the fixed pipe 20 protrudes toward the operating section 5 side beyond the base end surface of the fixed pipe 20, and this fitted portion is fixed with a string S. Note that the inner circumferential surface on the base end side of the fixed pipe 20 has a tapered portion 20a in which the circumferential wall becomes thinner toward the end surface.
is formed.

According to the endoscope having the above configuration, by bending the bending section 3 using the operation knob 10 of the operation section 5, it is possible to direct the distal end section 4 toward a desired target site in the body cavity while performing observation. If necessary, the treatment instrument 23 is inserted through the forceps port 21 of the operating section 5 and guided out through the channel opening 19 to perform biopsy or other desired treatment.

By the way, in this embodiment, the distal end portion of the channel tube 14, that is, the portion connected to the fixed pipe 20 provided in the channel opening 19, is formed as a hard portion 22 that is harder than other portions. As shown in FIG. 3, when the treatment instrument 23 is inserted with the curved portion 3 strongly curved with a small curvature, the distal end 23a of the treatment instrument 23 moves outward from the peripheral wall until it reaches the hard part 22 of the channel tube 14. However, the hard part 22
When the hard part 22 reaches the tip 2 of the treatment tool 23 due to its hardness, as shown in FIG.
Even if it is pressed by 3a, it hardly deforms. Therefore, the treatment instrument 23 is guided so that its distal end 23a is coaxial with the fixed pipe 20, so that it is smoothly led out from the channel opening 13 into the body cavity. Moreover, since the inner circumferential surface on the base end side of the fixed pipe 20 is formed into a tapered portion 20a, this also makes it difficult for the tip 23a of the treatment tool 23 to catch on the end surface of the fixed pipe 20. Guidance becomes smoother.

Note that the present invention is not limited to the above-mentioned embodiment, and as shown in FIG. A tape 25 consisting of the following was wound spirally. This tape 25 has a non-porous solid portion 25a formed in a portion around which the hard portion 22 of the channel tube 14 is wound. With this configuration, the coating 24 maintains airtightness between the inside and outside of the channel tube 14,
The hard part 22 of the channel tube 14 can be made even harder by the solid part 25a of the tape 25.

As described above, the present invention extends the distal end portion of the channel tube connected to the channel opening of the distal end component via the fixed pipe to a position extending further toward the operating section from the end of the fixed pipe on the operating section side. Since the hard part is made harder than the above-mentioned part, even if the treatment instrument is inserted through the channel tube in a strongly curved state, the tip of the treatment instrument can be prevented from getting caught on the end surface of the fixed pipe. Therefore, the treatment instrument can be inserted smoothly and the channel tube will not be damaged due to forced insertion, which is extremely useful in practice.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a conventional endoscope with its curved portion curved, Figs. 2 to 4 show an embodiment of the present invention, and Fig. 2 is a sectional view of the distal end of the insertion section. FIGS. 3 and 4 are schematic diagrams of an endoscope, and FIGS. 3 and 4 are sectional views showing a treatment instrument inserted into a channel tube, respectively. FIG. 5 is a sectional view of a channel tube showing another embodiment of the present invention. 4... Tip component, 14... Channel tube, 19... Channel opening, 20... Fixed pipe, 22... Hard part.

Claims (1)

[Claims for Utility Model Registration] (1) A fixed pipe is provided at the channel opening of the tip component, and the tip of the channel tube is fitted and connected to the outer periphery of the fixed pipe,
The channel tube is characterized in that the distal end connecting portion connected to the fixed pipe is made of a hard part that is harder than other parts from the operating section side end of the fixed pipe to a position extending further toward the operating section side. Endoscope. (2) The endoscope according to claim 1, wherein the channel tube is made of a crystalline polymer material having a porous structure, and the hard part thereof is non-porous. (3) The endoscope according to claim 2, wherein the crystalline polymer material is polytetrafluoroethylene.