JPH03280918A - Endoscope - Google Patents

Abstract

PURPOSE:To prevent the occurrence of damage or cracks when a treating tool is repeatedly inserted and removed by forming a channel tube provided on a curved section on the tip side of an insertion section into a nearly uniform thickness mixedly with hard sections and soft sections. CONSTITUTION:A channel tube 27 is provided in an insertion section 9 inserted into a body cavity. The channel tube 27 provided on a curved section 12 at the tip side of the insertion section 9 is formed into a nearly uniform thickness mixedly with hard sections 27d and soft sections 27e. Thus, even if a treating tool is repeatedly inserted and removed, damage or cracks rarely occur, the treating tool can be smoothly inserted and removed, buckling rarely occurs when bent, the curved section 12 can be made small in diameter, and excellent durability is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement of a channel tube provided in an insertion section of an endoscope.

[Prior Art] In recent years, medical treatments have become available that allow the observation of internal organs in a body cavity by inserting an elongated insertion section into a body cavity, and the use of a treatment instrument inserted into a treatment instrument channel to perform various treatments as necessary. endoscopes are widely used. Furthermore, in the industrial field, industrial endoscopes that can observe and inspect the interiors of boilers, turbines, engines, chemical plants, etc. are widely used.

The insertion section of this endoscope is provided with a hard distal end on the distal end side, and a bendable curved section on the rear side adjacent to the distal end. This bending portion can be bent in the vertical/horizontal direction by rotating a bending operation knob provided on the operation portion.

By the way, the above-mentioned curved portion is, for example, in the medical field,
Various improvements have been made in response to the medical need to thoroughly and reliably observe and treat organs within body cavities, and recently there has been a trend toward smaller curvature radii and thinner diameters.

Under these circumstances, the channel tube that forms the treatment instrument channel of the endoscope will not buckle even if the radius of curvature of the curved part becomes small, and in order to make the curved part smaller in diameter, It is necessary to reduce the wall thickness.

Conventionally, as means for preventing buckling of the channel tube, as disclosed in, for example, Japanese Unexamined Utility Model Publication No. 59-14601 and Japanese Unexamined Patent Publication No. 62-240022,
Generally, a coil is wound around a channel tube.

However, when the coil is wound around the channel tube, the outer diameter increases, which becomes an obstacle when reducing the diameter of the curved portion.

[Problems to be Solved by the Invention] On the other hand, in recent years, large-sized treatment instruments that can collect a large amount of cells have been developed, but these treatment instruments have a thick shaft diameter and a relatively long hard part, so the channel is difficult to solve. It is difficult to bend along the curvature of the tube, and when inserting or removing the treatment tool from this channel tube, the treatment tool presses the inner surface of the channel tube, which not only increases the amount of insertion/removal force, but also causes the treatment tool to be inserted into and removed from the channel tube. Repeated insertion and removal may cause damage or cracks to the portion of the channel tube that is under pressure.

The present invention has been made in view of the above-mentioned circumstances, and it is possible to smoothly insert and remove treatment instruments without causing damage or cracks even if they are repeatedly inserted and removed, and to prevent buckling even when curved. It is an object of the present invention to provide an endoscope that has a channel tube that is not only difficult to cause, but also allows the curved portion to be reduced in diameter and has excellent durability.

Means for Solving the 18 Problems The present invention provides an endoscope having a channel tube in an insertion section to be inserted into a body cavity, in which the channel tube provided at a curved portion on the distal end side of the insertion section has a substantially uniform shape. It is thick and has a mixture of hard and soft parts.

[Function] In the present invention, the channel tube is formed with a substantially uniform wall thickness and a mixture of hard parts and soft parts. Even if the treatment part presses the inner surface of the channel tube when inserting and removing instruments, the part that receives this pressure is made of a hard part, so even if the treatment instrument is repeatedly inserted and removed, no damage or cracks will occur. Insertion and removal of chests, treatment instruments, etc. become smoother. Furthermore, when the curved portion is curved, the soft portion of the channel tube self-deforms and curves, so buckling does not occur. Furthermore, since the wall thickness of the channel tube is uniform, the internal components of the curved portion can be laid out with high density, and the diameter of the curved portion can be reduced accordingly.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

1 to 9 show a first embodiment of the present invention, FIG. 1 is a cross-sectional view of the main part of the insertion part, FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG.
Fig. 3 is an enlarged view of the part ■ in Fig. 1, Fig. 4 is an enlarged sectional view of the distal end of the insertion section, Fig. 5 is a schematic diagram of the endoscope device, and Fig. 6 is a view of the ■ arrow in Fig. 4. Figure 7 is a diagram showing a monitor image,
FIG. 8 is a diagram corresponding to FIG. 7 according to another embodiment, and FIG. 9 is a diagram corresponding to FIG. 7 according to another embodiment.

Reference numeral 1 in FIG. 5 is an endoscope device, and this endoscope device W11 has an endoscope 2, a light source device @3, and a video processor 4.
A viewing monitor 5 for displaying or recording video signals output from the video processor 4, a VTR deck 6, a video printer 7, a video disk 8, etc. can be freely connected to the video processor 4.

The endoscope 2 includes an elongated, for example, flexible insertion section 9 that is inserted into a body cavity, and a large-diameter operation section 10 is connected to the rear end of the insertion section 9.

Further, a hard tip portion 11 is provided at the tip of the insertion portion 9, and a bendable curved portion 12 is provided on the rear side adjacent to the tip portion 11. By rotating a bending operation knob (not shown) provided on the operating section 10, the bending section 12 can be moved UP/DOllN.

It can be bent arbitrarily in the LEFT/RIGHT direction.

The outer periphery of the curved portion 12 is covered with a curved rubber 13, and a large number of curved portions 15 are arranged on the inner periphery of the curved portion 12 along the pipe length direction via braids (mesh pipes) 14.
5 in the circumferential direction via joint axes (not shown).
They are connected to each other with a phase shift of .degree., and the most extreme curved portion 15 is fixed to the tip main body 11a of the tip 11. Further, the rearmost curved portion 15 is fixed to a ring-shaped base 16 connected to the rear portion of the insertion portion 9.

Approximately 18 wire guides 17 are arranged on the inner periphery of each curved portion 15.
They are fixed at appropriate positions, such as at 0° intervals, by brazing, gluing, or other means. An angle wire 18 is inserted through this wire guide 17, and the tip of each angle wire 18 is connected to the most extreme curved portion 15 or the tip main body 11a.
It is fixed by means such as brazing, and its rear end side is connected to a bending operation knob provided on the operating section 10 via a bending operation drum (not shown).

Further, an objective lens system 19 is disposed at the distal end portion 11,
An imaging section 20 is disposed at the rear of the objective lens system 19. The solid-state image sensor (hereinafter referred to as rsIDJ) of this image sensor 20
) 21 is disposed at the imaging position of the objective lens system 19. Furthermore, the board 2 on which this 5ID21 is mounted
A drive signal line 22a and a video signal line 22b are connected to 1a.

The 5ID 21 and the substrate 21a are covered with a shield frame 24, and the shield frame 24 is fixed to the tip main body 11a.

The video signal line 22b is twisted around the drive signal line 22a, and its outer periphery is covered with a sheath 25. Further, both the signal lines 22a and 22b are extended to the operation unit 10 side and connected to the video processor 4 via a scope cable 23 or the like, and a drive signal generation circuit (not shown) built in the video processor 4 is provided. , and are respectively connected to the video signal processing circuit.

Further, a treatment instrument channel cap 26 is attached to the rear end of the treatment instrument channel through hole 11b opened in the distal end portion 11, and the distal end of a channel tube 27 is fitted into the treatment instrument channel cap 26. Furthermore, the rear end of the channel tube 27 is connected to the treatment instrument insertion port 10a opened in the operating section 10. A treatment instrument channel is constituted by each component between the treatment instrument insertion port 10a and the treatment instrument channel through hole 11b.

Further, the channel tube 27 has a three-layer structure,
Innermost tube 2 with almost uniform wall thickness over the length of the tube
7a is a foamed material having a low coefficient of friction and stretchability, such as stretched foamable tetrafluoroethylene resin (hereinafter referred to as [stretched foamable PTFE)].
It is made of material (abbreviated as J). Further, the intermediate layer tube 27b is made of a flexible material, for example, fluororubber. Furthermore, the outermost layer is stretchable P
It is formed by winding a tape 27c, such as TFE, which has a low coefficient of friction and is stretchable.

The tube 27a, which is the innermost layer, can have a desired hardness by appropriately setting the foaming rate.

Conventionally, the channel tube 27 often has a single-layer structure, and the foam material used has a uniform foaming rate.

The tube 27a according to the present invention has a partially different foaming rate and is integrally formed with a hard part 27d and a soft part 27e mixed in one tube 27a.

Specifically, as shown in FIGS. 1 and 3, foaming is applied to a portion of the tube 27a that is most likely to interfere when the channel tube 27 is bent, that is, a portion of the tube 27a that is opposite to the wire guide 17. hard part 27d (first
The hatched part in the figure) is formed, and the other parts are formed of a soft part 27e with a relatively high foaming rate, similar to the conventional one.

As the means for forming the tube 27a, for example,
First, PTFE resin has a high foaming rate (
form a soft) tube. Next, this tube is set in a jig that exposes only the part to be hardened, and then the tube is heated and re-fired, so that only the part exposed by the jig, that is, only the directly heated part, is heated. The foaming rate of the tube 27a becomes low (soft), and a tube 27a including a hard part 27d and a soft part 27e can be obtained.

On the other hand, in addition to the above-mentioned components, the curved portion 12 includes a pair of light guides 28 that transmit the illumination light from the light source bag @ 3 to the distal end portion 11 side, and an objective provided on the distal end portion 11. Air and water supply nozzle 29 (sixth
An air/water supply tube 30 and the like connected to the main body (see figure) are built-in.

Reference numeral 31 denotes a treatment instrument such as forceps, which is inserted into and removed from the treatment instrument insertion port 10a into the channel tube 27 within the body cavity for diagnostic treatment.

(for production) Next, the operation of the embodiment with the above configuration will be explained.

First, insert the insertion section 9 of the endoscope 2 into a body cavity, etc., and rotate the bending operation knob (not shown) provided on the operation section 10 on the hand side. The wires 18 are each bent in a predetermined manner, and the curved portions 12 that are set on the distal end side of the insertion portion 9 are LIP/DOWN, LEFT/
Curves in the R1 leaf ■ direction.

The tube 27a of the channel tube 27 built into the insertion section 9, which is inserted into the curved section 12, is connected to the hard section 2.
7d and the soft portion 27e are integrally formed, so when the curved portion 12 is bent, the soft portion 27d is deformed and the channel tube 27 is bent. Therefore, even if the curved portion 12 is curved to the minimum curvature, the channel tube 27 will curve without difficulty and will not buckle.

Further, horizontal drive pulses and vertical drive pulses output from the drive signal generation circuit of the video processor 4 are transmitted to the insertion section 9.
The 5ID 21 is driven by transmitting the drive signal line 22a arranged in the drive signal line 22a. On the other hand, information on the inside of the body cavity, etc., which is incident from the objective lens system 19 provided at the distal end 11 of the insertion section 9 and imaged on the S[D21, is photoelectrically converted and transmitted as a video signal through the video signal line 22b. and the above video processor 4
An observation monitor 5, a VTR deck 6, and a video signal processing circuit connected to the video processor 4,
Images of the inside of the body cavity are displayed or recorded on a video printer 7 and a video disk 8.

Incidentally, the signal lines 22a and 22b are generally housed in a state where they are twisted together in advance so that sufficient durability can be guaranteed even if the bending section 12 is repeatedly bent. Therefore, each signal line 2 in a twisted state
Variations tend to occur in the lengths of the signal lines 2a and 22b, and variations also occur when each of the signal lines 22a and 22b is cut to a specified length during wiring assembly. As a result, the length of the signal wires 22a and 22b assembled in a twisted state is
Each endoscope is different, causing variations in drive signal delay.

a horizontal drive pulse transmitted through the drive signal line 22a;
Further, the vertical drive pulse is easily affected by the variation in the delay of the drive signal line, which may cause image disturbance.

Since the drive signal line 22a in the embodiment shown in the figure is arranged in a straight line in the center of the cable strands, variations in line length are less likely to occur, and variations in cutting can be suppressed to a minimum. , variations in drive signal delay are less likely to occur, and image clarity can be improved.

In addition, a channel tube 27 built into the insertion section 9
On the other hand, the treatment instrument insertion port 10 opened in the operation section 10
When the treatment tool 31 such as forceps is inserted and removed from a, if the curved portion 12 is curved, the treatment tool 31 presses against the inner wall of the curved channel tube 27 and moves along the curvature of the channel tube 27. curved.

The hard part 27d of the tube 27a constituting the innermost layer of the channel tube 27 is
Since the channel tube 27a is formed in the part facing the wire guide 17, which is the part that is most likely to interfere with the channel tube 7, even if the treatment instrument 31 presses the inner wall of the tube 27a, the channel tube 27a will not interfere with the wire guide 17. Therefore, damage to the channel tube 27 can be minimized.

In addition, since the channel tube 27 is made of fluororesin, it has a low coefficient of friction, and the sliding resistance with other components when bending and the sliding resistance when inserting and removing the treatment instrument 31 are reduced. , durability is improved.

Furthermore, channel tube 27 1-727a
Since the hard part 27d and soft part 27e formed in the tube 27a are obtained by changing the foaming rate, in other words, by changing the characteristics of the material, it is possible to mold the tube 27a to have a substantially uniform wall thickness without any unevenness. , the channel tube 27 not only moves smoothly with other components during bending, resulting in less damage, but also has no local unevenness.
The wall thickness of the curved portion 12 can be reduced, and the built-in density of the curved portion 12 can be increased, and the thickness of the curved portion 12 can be reduced accordingly.

Furthermore, the amount of force required to insert and remove the treatment instrument 31 is reduced, making it easier to handle and allowing prompt treatment.

In the illustrated embodiment, the hard part 27d of the tube 27a
is formed in the part facing the wire guide 17, but is not limited to this, but is not limited to a part facing the joint axis (not shown) connecting the curved part 15, or a part facing the shoulder opening 15a of the curved part 15, etc. When inserting and removing the treatment instrument 31, this treatment instrument 3
It is only necessary that the hard portion 27d be formed in a portion that is pressed by the channel tube 27 and is likely to interfere relatively violently with other components of the channel tube 27. Further, the hard portion 27d may be locally formed in a portion where interference is particularly severe.

By the way, if the treatment instrument channel through hole 11b is provided between the objective lens system 19 exposed at the distal end 11 and the light guide 28, as shown in FIG. As shown in the figure, the shadow 31a of the treatment instrument 31 protruding from the treatment instrument channel through-hole 11b is projected, which hinders the treatment and observation of the treatment area (
.

On the other hand, as shown in FIGS. 8 and 9, the treatment tool channel through hole 11b, the objective lens system 19, and the light guide 2
8 are arranged in a line, and the through hole 11b for the treatment instrument channel is arranged on one end side, the shadow of the treatment instrument 31 will appear on the back side of the image of the treatment instrument 31 itself. No shadow is cast on the screen.

(Second Embodiment) FIG. 10 is a sectional view of essential parts of an endoscope according to a second embodiment of the present invention.

In this embodiment, the channel tube 27 is connected to the distal end 11.
It can be removed from the side, and the treatment instrument channel through hole 11b that opens in the distal end 11 is composed of a large diameter section 11C on the distal end side and a small diameter section 11d behind it. The body portion 26a of the mouthpiece 26, which is press-fitted into the tip of the channel tube 27 at the rear, is inserted into the portion 11d. The body portion 26a of this mouthpiece 26 is fitted into the small diameter portion 11d of the treatment instrument channel through hole 11b with a clearance fit, and the engagement groove 26 is formed on the outer periphery of this body portion 26a.
b is engraved.

Further, a flange 26G is formed at the tip of the mouthpiece 26, and a sealing member 32 such as an O-ring is provided between the flange 26c and the bottom of the large diameter portion 11c of the treatment instrument channel through hole 11b. has been done.

Further, a machine screw 33 is screwed into the circumferential side of the tip portion 11,
The tip portion 33a of this machine screw 33 is engaged in the engagement groove 26b of the cap 26, and the cap 26 is prevented from being removed. Furthermore, the back surface of the machine screw 33 is filled with a filler material 34.

In the above configuration, the damaged channel tube 2
7, first uninstall the channel tube 27 on the operating section 10 (see Figure 5), and
The machine screw 33 screwed into the tip 11 is removed together with the filler 34.

Then, the channel tube 27 is pulled out together with the mouthpiece 26 from the treatment instrument channel through hole 11b side opened in the distal end portion 11.

Next, a new channel tube 27 is installed in a predetermined position, and after the cap 26 is prevented from being removed using a machine screw 33, the back surface of this machine screw 33 is filled with a filler 34.

According to this embodiment, the channel tube 27 can be removed from the distal end side, and there is no need to disassemble the insertion part and the curved part as in the conventional case, and replacement is easy and workable.

[Effects of the Invention] As explained above, according to the present invention, the channel tube provided at the curved part on the distal end side of the insertion section is formed with a substantially uniform wall thickness and a mixture of hard and soft parts. So,
Damage and cracks are less likely to occur even if treatment instruments are repeatedly inserted and removed, and insertion and removal of treatment instruments is smoother.In addition, buckling is less likely to occur even when curved, and the diameter of the curved part is reduced. It is possible to achieve the following effects, such as excellent durability.

[Brief explanation of the drawing]

1 to 9 show a first embodiment of the present invention, FIG. 1 is a cross-sectional view of the main part of the insertion part, FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG.
Fig. 3 is an enlarged view of the part ■ in Fig. 1, Fig. 4 is an enlarged sectional view of the distal end of the insertion section, Fig. 5 is a schematic diagram of the endoscope device, and Fig. 6 is a view of the ■ arrow in Fig. 4. Figure 7 is a diagram showing a monitor image,
8 is a diagram corresponding to FIG. 7 according to another embodiment, FIG. 9 is a diagram corresponding to FIG. 7 according to another embodiment, and FIG. 10 is a main part of an endoscope according to a second embodiment of the present invention. FIG. DESCRIPTION OF SYMBOLS 1... Endoscope device, 2... Endoscope, 9... Insertion part, 12... Curved part, 27... Channel tube,
27d...hard part, 27e...soft part. Figure 1 Figure 2 LIP Figure 3 Figure 10 Figure 6 Figure 81! f Figure 7 Figure 9

Claims (1)

[Scope of Claims] In an endoscope having a channel tube in an insertion portion inserted into a body cavity, the channel tube provided at a curved portion on the distal end side of the insertion portion has a substantially uniform wall thickness and a hard portion. An endoscope characterized by having a soft part mixed therein.