JP2000279373A - Angle part of endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively protect a fragile part, which constructs the outer part of angle part, at the outer tube without spoiling the function that is necessary for outer tube of angle part by setting a protective cover on the peripheral side of the part that covers the end part ring that constructs a bending tube at the outer tube. SOLUTION: The protective cover 37 is set on end part ring 30a, 32b, which are a fragile and non-bending part of full length of outer tube 34 that is comprised of EPDM at the angle part. The protective cover 37 is made of a thin synthetic resin film of several to several tens μm thickness. The synthetic resin film is harder than at least the outer tube 34 and has no elasticity. The protective cover 37, which is made of polyimide resin film that has harder member than that of outer tube 34, is mounted on the synthetic resin film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope used as a medical device or the like, and to an angle portion forming an insertion portion thereof.

[0002]

2. Description of the Related Art An endoscope has a structure shown in FIG. In the figure, 1 is a main body operation unit, 2 is an insertion unit,
3 is a universal code. The insertion portion 2 is a flexible portion 2a that bends in an arbitrary direction along an insertion path such as in a body cavity from the side of the connecting portion to the main body operation portion 1, and a predetermined end is provided at the distal end of the flexible portion 2a. An angle portion 2b having a length is continuously provided, and a distal end hard portion 2c is continuously provided at a tip of the angle portion 2b. Although illustration is omitted in the distal end hard portion 2c,
At least an illumination unit and an observation unit are provided. The angle portion 2b is for directing the distal end hard portion 2c in a desired direction, and can be bent vertically and horizontally.
This bending operation is called an angle operation, and is performed by rotating an angle knob 4 provided on the main body operation unit 1.

Next, FIG. 6 shows a configuration of the angle portion 2b. It should be noted that in the figure, internal insertion members such as a light guide, a signal cable (image guide), and a treatment tool insertion channel are omitted. Thus, the angle part 2b is
A predetermined number of angle rings 10 are sequentially pivoted by pivot pins 11 to form a curved tube 12 having a node ring structure. Front and rear angle ring 1 with pivot pin 11
The pivot points between 0 and 10 are alternated up and down and left and right, so that the bending tube 12 as a whole can be bent up and down and left and right. The curved tube 12 is covered with a net 13 made of a braid of a wire such as a metal, and an outer tube 14 is attached to the outer periphery of the net 13.

[0004] Of the angle rings constituting the curved tube 12, end rings 10a and 10b located at both ends are connected to a soft portion 2a and a distal end hard portion 2c, respectively. For this purpose, the end ring 10a is fitted to the connecting ring 15 extending from the flexible portion 2a side, and the end ring 10b is fitted to the distal end body 16 constituting the distal rigid portion 2c. Then, the operation wires 17 for the bending operation are fixed to the end ring 10b at four positions, that is, up and down and right and left. Each of these operation wires 17 is inserted through an insertion hole provided in the pivot pin 11, and extends to the end ring 10a while being positioned at a predetermined position.
0a from the insertion pipe 18 fixed to
9. An operation wire 17 inserted through the close contact coil 19 is extended to the main body operation unit 1 and an angle pulley (not shown) rotated and operated by the angle knob 4.
It is wound around.

[0005] In the angle portion 2b configured as described above, the outer tube 14 serving as the outermost exterior portion is provided.
Must be formed of an elastic member because it expands and contracts during the angle operation, and must be held so that the inside of the angle portion 2b is completely sealed. Further, since the insertion portion 2 is inserted into a body cavity or the like, it is natural that the insertion portion 2 is not harmful to the human body, and must be excellent in chemical resistance because it is repeatedly washed and disinfected. Must.

Although both ends of the outer tube 14 are fixed, it is necessary to completely fix the outer tube 14 so as not to leak from the end of the outer tube 14. For example, Japanese Unexamined Patent Publication
As shown in, for example, Japanese Patent No. 154097, it is general that the inside of the outer tube is kept in an airtight state by being wound around the outer surface of the outer tube and then fixed by applying an adhesive. Further, Japanese Patent Application Laid-Open No. 10-127571 discloses that a fixing member formed of an elastomer such as urethane resin or a rubber member is cohesively fixed to the inner periphery of an outer tube, and the fixing member is connected to a flexible portion to which a curved tube is connected. FIG. 1 shows a structure in which the fixing ring is fixed to a concave groove or the like provided in a distal end body constituting a distal end main body constituting a distal end rigid portion.

In any of the above-mentioned fixing methods, the outer tube partially expands and contracts at the time of the angle operation, so that the fixing portion does not fall off during the expansion and contraction. It must exhibit the fixing strength. Here, the end rings located at both ends of the curved tube are fitted to the connection ring on the soft part side and the tip main body, respectively. Therefore, these both end rings can be used at the time of an angle operation or when an external force is applied. It is a non-curved part that does not bend. So, both ends of the outer tube
Positions near both ends of the curved tube, especially the connecting ring to the distal end body and the flexible portion of the end ring,
That is, it is stably fixed at a position where it is not pressed and deformed even when an external force acts. Thereby, the fixing strength of the outer tube is increased.

[0008]

By the way, the insertion portion of the endoscope is long, and there is a possibility that the insertion portion, especially the tip portion, may erroneously collide with a surrounding object or the like when carrying the endoscope. is there. Therefore, if the outer tube is damaged or damaged due to the impact at the time of such a collision, contaminants in the body adhere to it and cleaning becomes difficult. In an extreme case, the cleaning liquid, the disinfecting liquid, etc. And the like, the members such as the solid-state imaging device provided in the insertion portion are contaminated to cause troubles, and inconveniences such as disconnection of cables and optical fibers occur. Further, the endoscope is provided with a treatment tool insertion channel through which forceps and other treatment tools are inserted for treating an affected part or the like. As the treatment tool, for example, a treatment tool having a sharp tip such as a forceps with a needle is used. If the distal end of such a treatment tool is brought into contact with the exterior part of the insertion portion by mistake, the sharp distal end may be pierced.

[0009] In the exterior portion of the entire insertion portion, the hard tip portion has extremely high strength against the action of an external force, and the angle portion and the soft portion are bendable. Can be absorbed to some extent. However, the connecting portion between the angle portion and the rigid portion at the distal end and the connecting portion between the angle portion and the soft portion have a limited length but are not bent. Therefore,
When a large impact force acts on the unbent portion, the possibility of breakage increases, and the possibility of breakage increases even when the sharp distal end of the treatment tool abuts. In addition, since the soft portion and the angle portion have a difference in the material of the exterior portion, etc., the angle portion generally has a lower strength against an impact force.

In general, the exterior portion of the angle portion is required to be made of a material having high elasticity in order to reduce resistance to the angle operation and to have properties such as chemical resistance. At present, urethane rubber and EPDM (ethylene propylene diene rubber) are usually used. Therefore, it is not always possible to select a material having a high strength against an external force such as an impact. As a result, of the outer tube, the portion located on the end ring that constitutes the non-curved portion of the curved tube that cannot absorb shocks or the like by being bent even when an external force is applied to the surface, that is, the hard base made of metal or the like The part that is almost fixedly in contact with the upper part absorbs shock by the elastic force of the outer tube itself, so the surface is damaged even if a load due to a relatively small impact etc. acts, and a large impact acts Then, the outer tube may be damaged.

The present invention has been made in view of the above points, and an object of the present invention is to effectively protect a fragile portion of an outer tube constituting an exterior portion of an angle portion. It is in.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a hard distal end provided with an angle portion which is bent by remote control, and the angle portion is provided with a soft bendable in any direction. In the insertion part of the endoscope with a series of parts,
The angle portion includes a curved tube having a node ring structure formed by pivotally attaching a predetermined number of angle rings, a net mounted on an outer surface of the curved tube, and a curved tube mounted on the outside of the net. An outer ring tube provided to extend to a position covering an end ring connected to the distal end hard portion and the soft portion of the angle ring constituting the tube,
A portion of the outer tube covering the end ring is provided with a protective cover made of a member harder than the outer tube so as to cover at least a part of the outer peripheral side thereof. is there.

Here, it is desirable that the protective cover be attached so as to extend over substantially the entire length including the end ring and a connection portion to another angle ring adjacent to the end ring. Generally, it is made of urethane rubber or ethylene propylene diene rubber, but the protective cover can be made of a film, tube or coating harder than the material of the outer tube, thin metal tube or hard resin tube. it can. As a method for fixing the outer tube, it is also possible to use a thread winding and an adhesive.Both protective covers are bonded from both ends of the outer tube over a predetermined length, and the outer tube is bonded to each end ring. The outer tube can be fixed by providing an adhesive layer so that the ends of both protective covers are bridged between the distal end hard portion and the soft portion. And
If the adhesive surface of the outer tube is primed in advance,
Further, the bonding strength can be increased.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, FIG. 1 shows a configuration of a distal end portion in an insertion portion of an endoscope. In the figure, reference numeral 20 denotes a hard tip portion, 21 denotes an angle portion, and 22 denotes a soft portion. Although not shown, the distal end hard portion 20 is provided with an illumination unit equipped with an illumination lens.
3 are provided, and these constitute an observation means of the endoscope. The observation unit 23 includes an objective optical system 24 and a solid-state imaging device 25 such as a CCD provided at an image forming position of the objective optical system 24. Further, a treatment tool deriving opening 26 is provided in the distal end hard portion 20 for deriving forceps and other treatment tools, and a connection pipe 26a is provided in the treatment tool derivation opening 26 by being inserted thereinto. A treatment instrument insertion tube 27 is provided so as to fit into the connection pipe 26a. Therefore, the distal end rigid portion 20 has a distal end main body 28 having a predetermined shape for mounting these members.
And a tip cap 29 that covers the front portion of the tip body 28. The distal end body 28 is formed of metal from the viewpoint of structural strength and workability, and the distal end cap 28 covers the distal end of the distal end main body 28 so as to prevent the distal end main body 28 from being exposed to the outside. Reference numeral 29 is formed of a synthetic resin having electrical insulation.

The angle portion 21 has a curved tube 32 formed by sequentially connecting the angle rings 30 via pivot pins 31. A net 33 is attached to the curved tube 32. An outer tube 34 is attached on the upper side. The pivot pins 31 for pivotally connecting the front and rear angle rings 30 are provided at two locations each in the order of up and down and left and right, so that the angle portion 21 can be bent up and down and left and right. For this purpose, four operating wires 35 are provided with a 90 ° phase relationship. The end ring 30a at the most proximal position of the angle ring 30 is fitted to the connection ring 36 extending from the flexible portion 22, and the end ring 30 at the most distal position.
b is fitted to the tip body 28. Therefore, the bending tube 32
Of these, both end rings 30a, 30b are
This is a non-curved portion that does not bend when a bending operation is performed by a push-pull operation or the like or when an external force is applied.

More specifically, in FIG. 1, the length L up to the mounting portion of the pivot pin 31 connecting the end rings 30a, 30b and the adjacent angle ring 30 is non-curved. And a portion between them is a curved portion. Here, the ends of all the angle rings 30 including the end rings 30a and 30b have a shape projecting obliquely.
The connecting projection 30P for mounting the end ring 30 is further protruding, so that the non-curved portion is strictly restricted to the end ring 30P.
a, a pivot pin 31 in the connecting projection 30P of 30b
Up to the fastening part.

The outer tube 34 is made of, for example, EPDM in order to exhibit elasticity and chemical resistance. The outer tube 34 is connected to the end rings 30a, 30a.
It extends to the end position of b or beyond it to seal the inside as an exterior part of the angle part 21. Therefore, it is necessary for the outer tube 34 to fully exhibit the function of completely sealing the angle portion 21 and not to be damaged by an external impact or the like over its entire length. Increasing the thickness of the outer tube 34 increases the strength. However, increasing the thickness of the outer tube 34 not only increases the diameter of the entire insertion portion but also increases the resistance during the angle operation. Here, in the curved portion of the outer tube 34, the impact is absorbed to some extent by bending when the impact is applied. Therefore, the thickness dimension of the outer tube 34 is set based on the strength against impact at the curved portion. As a result, when an impact or the like acts on portions that are located on the end rings 30a and 30b that are non-curved portions, sufficient strength cannot be obtained.

Here, in the entire length of the outer tube 34, the portions on the end rings 32a and 32b which are fragile portions are non-curved portions of the entire outer tube 34. Therefore, it is not necessary for the outer tube 34 to have at least elasticity at a position covering the non-curved portion. Of course, since it is an exterior part of the angle part 21, characteristics such as chemical resistance are required, but since elasticity is not required in this part, protection is provided so as to have mechanical strength. For this reason, on the outer peripheral surface of the outer tube 34, a protective cover 37 is provided limited to a portion that covers portions on the end rings 32a and 32b. Here, the protective cover 37 is made of a thin synthetic resin film having a thickness of about several μm to several tens of μm. This synthetic resin film is at least harder than the outer tube 34, and is made of a polyimide resin such as a Kapton film (trade name). It is composed of a film. The protective cover 37 made of the synthetic resin film is a member that does not have elasticity and is harder than at least the material of the outer tube 34.

When the protective cover 37 is mounted on the outer tube 34, the protective cover 37 has a width dimension that covers the entire circumference of the outer tube 34, and has a longitudinal dimension that is equal to the length of the end ring 32a. A rectangular film shorter than the entire length of 32b is used. An adhesive is applied to the inner surface of the film, and the film is wound around the outer tube 34.
When the protective cover 37 is wound, a certain compressive force acts on the outer tube 34. An adhesive is applied to both ends and the joint of the protective cover 37 to prevent the protective cover 37 from peeling off. Further, the protective cover 37 is not attached only for a predetermined length from the end of the outer tube 34. Thereby, the outer tube 34 is fixed to the curved tube 32 and the inside of the insertion portion is sealed by applying the thread winding 38 and the adhesive to the portion where the protective cover 37 on the distal end side is not provided.

With the above configuration, the strength of the portion of the outer tube 34 that covers the end rings 30a and 30b is greatly improved. That is, even if the insertion portion collides with another object and a large impact force acts thereon, it is protected by the hard protective cover 37 and no impact force is directly applied to the outer tube 34. Therefore, the strength of the outer tube 34 at the positions on the end rings 30a and 30b against impact is greatly improved, and the outer tube 34 can be prevented from being damaged or broken. In addition, even if an extremely sharp object collides with a sharp object such as the tip of a forceps with a needle, there is no danger of the protective cover 37 being pierced by the tip, and the non-curved portion of the outer tube 34 is extremely effectively protected. Is done.

The protective cover 37 is made of a hard film and has no elasticity.
When 1 is bent, the extension of the outer tube 34 does not reach the portion where the protective cover 37 is provided. Therefore, the resistance to the angle operation for bending the angle portion 31 does not increase.

Here, in the embodiment shown in FIG. 1, the end rings 30a and 30
2, the protective cover 40 may be mounted so as to cover substantially the entire length of the non-curved portion, as shown in FIG. As can be seen from the figure, the protective cover 40 made of a thin film of a polyimide resin or the like has a width dimension that completely covers the outer periphery of the angle portion 21, and the entire length is the end portion of the outer tube 34. , And a dimension to cover the connection projection 30P of the end rings 30a, 30b to the fastening position of the pivot pin 31.

With this configuration, almost the entire non-curved portion of the outer tube 34 can be protected by the protective cover 40. However, in this case, since the outer tube 34 cannot be fixed by thread winding, an adhesive is applied to the inner surface and the front surface of the outer tube 34 to form the end ring 30a, 30b and the distal end hard portion 20. 28 and the surface of the connection ring 36, and the adhesive 41 is filled between the end of the protective cover 40 and the tip body 28 and the connection ring 36 so as to provide a sealing property. While improving the adhesive strength. In this case, it is desirable that the bonding surface of the outer tube 34 made of rubber be subjected to a process for improving the adhesiveness, for example, a primer process. Here, when EPDM is used as the material of the outer tube 34, a primer containing toluene or xylene as a main component is preferably used as the primer.

Further, as shown in FIG. 3, a protective cover 42 made of metal in a thin ring shape can be used. The protective cover 42 completely covers the entire non-curved portion of the outer tube 34 or is slightly shorter. Since the protective cover 42 is made of metal, even if the protective cover 42 is extremely thin, the outer cover tube 34 is not affected by an impact or the like.
The impact force does not act directly on the surface, and the protection function is significantly improved. In particular, the protection function at the time of collision of a treatment tool having a sharp tip is extremely high.

Here, the protective cover 4 made of a metal ring
No. 2 has no elasticity in the radial direction, so that the outer tube 34 made of rubber is fitted to the end rings 30a and 30b while being bent to some extent, and the outer tube 34 and these end portions The bonding surfaces of the rings 30a, 30b, the tip body 28, and the connecting ring 36, and the protective cover 42 are further bonded with an adhesive 43, so that the outer tube 34 has a bonding function and a sealing function inside the angle portion. Can be demonstrated. In addition, by performing the bonding after performing the primer treatment on the bonding surface of the outer tube 34 and the like, the bonding strength of the bonding agent 43 can be improved.

Further, as shown in FIG. 4, the protective cover 44 can also be formed by forming a hard resin into a ring shape.
Can be configured. However, in the case of this protective cover 44 made of resin, it cannot be formed so thinly.
By forming the outer tube 34 and the protective cover 44 integrally, the protective cover 44 of the outer tube 34 is formed.
The part to be mounted is formed thin. Thereby, it is possible to hold the insertion portion so that the outer diameter does not increase. In this case, the end of the outer tube 34 is fixed by applying an adhesive after applying a thread 45. Therefore, the protective cover 44
It is preferable that the protective cover 44 is not provided for a predetermined length from the end of the outer tube 34 without extending to the portion where the step 5 is performed.

[0027]

As described above, according to the present invention, since the protective cover is provided on the outer peripheral side of the portion covering the end ring constituting the curved tube in the outer tube, the function required for the outer tube at the angle portion is provided. It is possible to effectively protect the easily breakable portion of the outer tube constituting the outer portion of the angle portion without damaging the outer tube.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an angle part showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of an angle part showing a second embodiment of the present invention.

FIG. 3 is a cross-sectional view of an angle part showing a third embodiment of the present invention.

FIG. 4 is a sectional view of an angle part showing a fourth embodiment of the present invention.

FIG. 5 is an overall configuration diagram of the endoscope.

FIG. 6 is a cross-sectional view of an angle part according to the related art.

[Explanation of symbols]

REFERENCE SIGNS LIST 20 Hard tip portion 21 Angle portion 22 Flexible portion 28 Tip body 30 Angle ring 30a, 30b End ring 31 Pivot pin 32 Curved tube 33 Net 34 Outer tube 36 Connection ring 37, 40, 42, 4
4 Protective cover 38, 45 Thread spool 41, 43 Adhesive

Claims (5)

[Claims] 1. An insertion part of an endoscope in which an angle portion which is bent by remote control is provided on a hard distal end portion, and a flexible portion which can be bent in an arbitrary direction is connected to the angle portion. A curved tube having a node ring structure formed by pivotally attaching a predetermined number of angle rings, a net mounted on an outer surface of the curved tube, and a net mounted outside the net to constitute the curved tube. The angle ring comprises an outer tube provided to extend to a position covering the end ring connected to the distal end hard portion and the soft portion, and a portion covering the end ring of the outer tube includes: An angle portion of an endoscope, wherein a protective cover made of a member harder than the outer tube is attached so as to cover at least a part of an outer peripheral side thereof. 2. The protection cover according to claim 1, wherein the end ring includes:
The angle part of an endoscope according to claim 1, wherein the end ring is mounted over a length range substantially covering the entire length including a connection part to another angle ring adjacent to the end ring. 3. The outer tube is made of urethane rubber or ethylene propylene diene rubber, and the protective cover is made of a film, a tube or a coating harder than the material of the outer tube, a thin metal tube or a hard resin tube. The angle part of the endoscope according to claim 1, wherein the angle part is constituted by: 4. The protective covers are adhered over a predetermined length from both ends of the outer cover tube, and the outer cover tubes are bonded to the respective end rings. The angle part of the endoscope according to claim 1, wherein an adhesive layer is provided so as to bridge between the hard part and the soft part. 5. The angle section of an endoscope according to claim 4, wherein the adhesive surface of the outer tube is subjected to a primer treatment.