JPH0630162Y2 - End of endoscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a tip portion of an endoscope, and more particularly, to improvement of a structure of a tip portion of an endoscope having a solid-state imaging device built therein.

[Prior Art] The insertion portion of an endoscope must be as thin as possible in order to reduce the pain to the patient. However, at the current state of the art, it is difficult to make a solid-state image sensor such as a charge coupled device (CCD) as thin as an image guide fiber bundle. Therefore, the tip portion main body incorporating the solid-state imaging device becomes thick to some extent.

However, if the flexible tube (concept including the curved portion) is also made thicker in accordance with it, the pain to the patient becomes great. Further, since the signal cable of the solid-state image pickup device does not become so thick, the space inside the flexible tube is wasted. Therefore, in an endoscope in which a solid-state image sensor is incorporated in the tip portion, it is general that only the tip portion main body is formed thicker than a flexible tube.

7 to 10 show the tip of such a conventional endoscope. In FIG. 7, 51 is a hard tip body. Reference numeral 52 is a bending portion which is formed at the tip portion of the flexible tube and can be bent by remote control. As shown in FIG. 7, the tip portion of the conventional endoscope is connected to the tip portion main body 51 and the bending portion 52 so that their tube axes coincide with each other.

FIG. 8 is an enlarged sectional view of the tip portion 51 thereof. 9 and 1
FIG. 0 is a sectional view taken along line IX-IX and line XX, respectively. In the figure, 53 is an objective optical system. 54 is the objective optical system 53
The forceps channel 55, which is a solid-state image sensor disposed at the image forming position of, and through which a treatment tool such as forceps is inserted is disposed on the upper edge side of the tip portion main body 1 while avoiding the solid-state image sensor 54. It Reference numeral 56 is a light guide bundle for illumination.

[Problems to be Solved by the Invention] However, in the distal end portion of the endoscope configured as described above, as shown in FIG.
However, it is abruptly bent at the portion where the thick tip portion main body 51 enters the thin curved portion 52. Then, when a treatment instrument such as forceps is inserted and removed, a large load is applied, which causes a problem such as a decrease in operability and a breakage of the treatment instrument. Depending on the type of the treatment instrument, the instrument cannot be inserted at all. I will end up.

However, in order to deal with this, if the diameter of the curved portion 52 is increased or the length of the distal end portion main body 51 is increased, the pain to the patient becomes great.

An object of the present invention is to provide a distal end portion of an endoscope which eliminates the above-mentioned conventional drawbacks and improves the insertion of the treatment instrument without increasing the pain to the patient.

[Means for Solving the Problem] In order to achieve the above-mentioned object, the distal end portion of the endoscope of the present invention is such that the distal end portion of the flexible tube has a hard distal end body having an outer diameter larger than that of the flexible tube. And the solid-state image sensor is arranged at the imaging position of the objective optical system in the tip body, and a forceps insertion passage for inserting a treatment tool such as forceps is inserted from the tip body into the flexible tube. The distal end of the endoscope is characterized in that the distal end main body and the flexible tube are eccentrically connected to each other in a direction in which the forceps insertion passage in the distal end main body approaches the tube axis of the flexible tube.

[Operation] The forceps insertion passage is bent inward when the forceps insertion passage is moved from the inside of the thick main body into the thin flexible tube. However, since the tip body and the flexible tube are eccentrically connected to each other in a direction in which the forceps insertion passage in the tip portion main body approaches the tube axis of the flexible tube, the bending of the forceps insertion passage is relaxed and a straight line is formed. It can have a similar shape.

[Example] An example will be described with reference to the drawings.

FIG. 1 is a side sectional view of a distal end portion of an endoscope, and 1 is a hard distal end body. Reference numeral 2 denotes a bendable portion that can be bent by remote control, and is formed as a part of the distal end portion of the flexible tube forming the insertion portion. Note that the bending portion 2 and the flexible tube portion may be separated and the bending portion 2 may not be called a flexible tube. However, in the present invention, the flexible tube is broadly regarded as a concept including the bending portion. I'm catching.

Reference numeral 4 is a known node ring that is rotatably connected to each other by rivets. Reference numeral 5 is a bending operation wire having one end fixed to a hole formed in the most advanced node ring 4 with silver brazing or the like and being pulled by an operation unit (not shown). 6 is a known mesh tube.
Reference numeral 7 denotes an outer cover made of a rubber material having a high elasticity.

The tip portion main body 1 is formed to have a diameter larger than that of the curved portion 2 in order to accommodate the solid-state imaging device 10 and other internal components. Signal cable 10a connected to the solid-state image sensor 10
Is much thinner than the solid-state image sensor 10, so that the curved portion 2 through which the signal cable 10a is inserted can be formed thin. As shown in FIGS. 5 and 6, the tip portion main body 1 is formed into a shape in which the side surface of the material having a circular cross section is cut into three planes at 90 ° intervals. 1
a is the plane part. This is to cut the useless portion of the portion that is large to accommodate the solid-state imaging device 10 inside, and reduce the pain to the patient as much as possible.

Reference numeral 11 denotes a tip body frame that forms an outer peripheral surface of the tip portion of the tip body 1, and a metal element frame 12 that fixes the solid-state imaging device 10 is disposed inside the tip body frame 11 via an insulating tape 13. It is fixed to. As the solid-state image sensor 10,
For example, a charge coupled device (CCD) or the like is used.

In front of the solid-state imaging device 10, an objective lens 14, which is an objective optical system, is housed and arranged in a lens frame 15 made of metal, and the lens frame 15 has an electrical insulating material 16 interposed therebetween.
It is fixed to the tip body frame 11. 17 is a spacer.
Reference numeral 18 is an O-ring for sealing.

In this way, the image receiving surface of the solid-state image sensor 10 is arranged so as to match the image forming surface of the objective lens 14. Further, the element frame 12 is formed in a cross section in which a circular cross section is cut off from both sides as shown in FIG. 3, and as described above, the tip end main body 1 surrounds the solid-state image sensor 10. The three surfaces are formed into a flat shape.

Reference numeral 21 denotes a forceps channel which is a forceps insertion passage for inserting forceps and other treatment tools, and is arranged in the tip body 1 in parallel with the element frame 12. The forceps channel 21 is formed to make the tip body 1 as thin as possible.
The tip body 1 has a thin wall thickness. It is taken into consideration that the forceps channel 21 is not bent in the tip end main body 1, so that buckling does not occur even if the wall thickness is made thin.

The upper edge of the tip body 1 along the forceps channel 21 is formed in a shape with a circular cross section. Then, as shown in FIG. 3, the illumination light guide bundles 25 are arranged along both sides of the forceps channel 21, and as shown in FIGS. 5 and 6, the cover lens 26 is It is provided on the emission end surface of the illumination light guide bundle 25. In addition, in FIG. 5 and FIG.
0 is the opening of the tip of the forceps channel 21. 14 a is the surface of the objective lens 14.

Returning to FIG. 1, the forceps channel 21 is the tip body 1
It is bent inward at the portion that enters from inside to inside the curved portion 2.
However, the present invention is devised to reduce the angle of this bend.

That is, 30 is a metal connecting pipe that connects the tip end main body frame 11 and the node ring 4 of the curved portion, and the rear side of the connecting pipe 30 is the most advanced one as shown in FIG. It is fitted to the outer surface of the node ring 4 and fixed to the node ring 4 by soldering or the like. Further, as shown in FIG. 3, the front side of the connecting pipe 30 is arranged so as to sandwich the tip end body frame 11 from both sides, and is fixed to the tip end body frame 11 by a pin 31. Then, by the connecting pipe 30, the tip end body 1
As shown in FIG. 2, the curved portion 2 and the curved portion 2 are eccentrically connected to each other. As shown in FIGS. 1 and 4, this eccentricity is eccentric in the direction in which the forceps channel 21 in the tip body 1 is brought closer to the tube axis of the bending portion 2, whereby the bending of the forceps channel 21 is prevented. Has been eased. Further, the eccentricity amount t is selected within a range in which the outer edge portion of the curved portion 2 does not project outward from the outer edge portion of the tip portion main body 1.

According to the distal end portion of the endoscope of the present invention thus configured, the bending angle of the forceps channel 21 is relaxed in a direction close to a straight line without thickening the bending portion 2 or lengthening the distal end body 1. can do.

[Advantages of the Invention] According to the distal end portion of the endoscope of the present invention, the flexible tube can be thickened at the connecting portion between the flexible tube and the distal end body containing the solid-state imaging device. Do n’t do it,
The bending of the forceps insertion passage can be relaxed, and the forceps insertion passage can be made closer to a straight line. Therefore, there is an excellent effect that the forceps and other treatment tools can be smoothly inserted and the operability and durability of the treatment tools can be significantly improved without causing extra pain to the patient.

[Brief description of drawings]

FIG. 1 is a side sectional view of a tip portion of an endoscope according to an embodiment of the present invention, FIG. 2 is a side view thereof, FIG. 3 is a sectional view taken along line III-III, and FIG. 4 is line IV-IV. Sectional drawing, FIG. 5 is a front view of the tip of the endoscope, FIG. 6 is a perspective view of the same, FIG. 7 is a side view of the tip of a conventional endoscope, and FIG. FIG. 9 is a sectional view taken along line IX-IX, and FIG. 10 is a sectional view taken along line XX. DESCRIPTION OF SYMBOLS 1 ... Tip part main body, 2 ... Curved part, 4 ... Node ring, 10 ... Solid-state imaging device, 11 ... Tip part main body frame, 12 ... Element frame, 14 ... Objective lens, 21 ... Forceps channel, 30 ... Connection pipe.

Claims (1)

[Scope of utility model registration request] 1. A rigid tip body having an outer diameter larger than that of the flexible tube is connected to the tip of the flexible tube, and a solid-state imaging device is disposed in the tip body at an image forming position of an objective optical system. With
At the distal end of the endoscope in which a forceps insertion passage for inserting a treatment tool such as forceps is inserted from the tip body into the flexible tube, the forceps insertion passage in the tip body approaches the tube axis of the flexible tube. The distal end portion of the endoscope is characterized in that the distal end portion main body and the flexible tube are eccentrically connected in the direction of movement.