JP2001238851A - Flexible tube of endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible tube which assists an inserting part to make a smooth, easy, and prompt inserting operation while correcting a flexible route straight among the inserting routes, by maintaining the difference in flexibility in the flexible direction toward the axis of the tube and by forming, at the same time, a hardness shifting part which has the difference of hardness toward the circumference between a high hard flexible part and a low hard flexible part. SOLUTION: At a flexible tube part 20a which constitutes an inserting part 20, a fixed length from a joining side to an operating part of a main body corresponds to a high hard flexible part 20aH, while a fixed length from a joining side to an angle part 20b corresponds to a low hard flexible part 20aS. Between the high hard flexible part 20aH and the low hard flexible part 20aS, a hardness shifting part 20aT is installed which changes the flexibility toward the direction of circumference. At the hardness shifting part 20aT, the high hard flexible part 20aH at both sides, left and right, and the low hard hard flexible part 20aS, at both sides up and down, respectively constitute a wave form as if they stretched out so as to make a V letter to the countepart.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a flexible tube in an insertion portion of an endoscope, and more particularly, to a method for correcting a curved path so as to be substantially straight like a colonoscope. The present invention relates to a flexible tube in an endoscope of a type inserted while being inserted.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 7, an endoscope widely used for medical purposes is provided with a main body operation section 2 connected to a base end of an insertion section 1 inserted into a body cavity or the like. In addition, the main body operation section 2 is substantially constructed by connecting a light guide flexible section 3 which is detachably connected to a light source device (not shown). The insertion portion 1 has a flexible tube portion 1a for most of the length from a portion connected to the main body operation portion 2, and the flexible tube portion 1a has an angle portion 1b, and the angle portion 1b has a tip portion main body. 1c are sequentially provided. The flexible tube portion 1a has flexibility in the bending direction.
b can be bent up and down and left and right (or at least one direction) by remote control from the main body operation unit 2. For this purpose, the main body operation unit 2 is provided with an angle operation means 4 which can be operated by an operator or the like with fingers. Further, an illumination window and an observation window are provided in the distal end portion main body 1c as an endoscope observation mechanism, and a treatment instrument insertion channel for inserting a treatment instrument such as forceps is opened.

[0003] Of the three parts constituting the insertion part 1, the flexible tube part 1a has a length that allows at least the distal end main body 1c to reach a predetermined observation target part, and the main body operation part 2
It is necessary to have a length enough to separate the patient from the patient or the like to the extent that it does not hinder the operator from gripping and operating the device. The flexible tube portion 1a needs to have flexibility over substantially the entire length, and in particular, a portion to be inserted into a body cavity or the like must have a more flexible structure. Here, the flexibility required for the flexible tube portion 1a is flexibility in the bending direction, and it is necessary to have sufficient strength in the expansion and contraction direction and the collapse direction.

Further, the flexible tube section 1a needs to have flexibility in the bending direction over substantially the entire length thereof. When the flexible tube section 1a is connected to the main body operation section 2, the flexible tube section 1a is pushed in when inserted into a body cavity or the like. For good thrust, considerable rigidity is required against bending. On the other hand, when the angle portion 1b is bent, the portion on the side continuous to the angle portion 1b follows the bend to some extent, and smoothly follows the bent insertion path to bend. It is desirable to increase the degree. Therefore, changing the degree of flexibility of the flexible tube portion 1a in the axial direction, that is, making the proximal end hard and the distal end soft, is advantageous from the viewpoint of insertion operability, reduction of patient's pain, and the like. It is. As described above, various methods are used to determine the degree of flexibility in the axial direction of the flexible tube portion 1a.

[0005] Here, as shown in FIG.
The flexible tube 10 constituting a is covered with a tubular mesh 12 formed by braiding a metal wire around a spiral tube 11 formed by spirally winding a metal strip on the innermost side, An outer skin layer 13 made of urethane resin or the like is laminated on and adhered to the tubular net 12. Therefore, in order to have a difference in hardness in the axial direction of the flexible tube 10, these spiral tubes 1
1, any one of the configuration of the tubular mesh body 12 and the outer skin layer 13 is changed in the axial direction.

As described above, an endoscope in which the flexible tube section 1a of the insertion section 1 changes the degree of flexibility in the axial direction is, for example, a colonoscope which is an endoscope for the lower digestive tract. Used as The colonoscope advances the distal end main body 1a of the insertion portion 1 from the anus to the inside of the large intestine via the rectum, and performs an examination of the inside of the large intestine.
It must pass through a large, curved part of the sigmoid colon. Moreover, unless the sigmoid colon is corrected so as to be as straight as possible, the insertion portion cannot be smoothly guided into the large intestine. For this purpose, the insertion section 1 is usually inserted in a state where the subject is lying on his side. Then, as shown in FIG. 9, when the insertion section 1 reaches the sigmoid colon C, the surgeon operates the angle operation means 4 provided on the main body operation section 2 and, as shown by an arrow in FIG. The angle portion 1b is bent in an appropriate direction (for example, upward) or returned to a straight state,
Further, while twisting, pushing, and pulling back the entire insertion portion 1, the distal end main body 1c is advanced along the sigmoid colon C as shown by the imaginary line in FIG. I am going to correct it.

[0007]

By the way, the above-mentioned procedure requires extremely skill and requires a long time, so that the subject suffers and the burden on the operator is great. Also, depending on the degree of bending of the sigmoid colon, etc., the operator may not be able to smoothly pass only by twisting the insertion portion, and in such a case, the subject may have to change the posture. This is not desirable in that the subject suffers from a great feeling of oppression. In particular, in order to advance the inside of the sigmoid colon, it is preferable that the flexible tube portion in the insertion portion bends smoothly following the bend of the path. It is more desirable that the flexible tube be hardened when straightening. In other words, when inserting a curved path while correcting it so that it becomes almost straight, if the flexible tube section only has a difference in hardness in the axial direction, it is difficult to insert the flexible pipe section from the viewpoint of insertion operability and the like. It is not always satisfactory.

The present invention has been made in view of the above points, and an object of the present invention is to improve the operation of inserting an insertion portion while straightening a curved path of an insertion path. An object of the present invention is to enable smooth and easy operation in a short time.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention covers a tubular structure which is flexible in a bending direction with a tubular mesh, and the tubular mesh has an outer skin layer. Are stacked,
A flexible tube of an endoscope having flexibility in a bending direction over substantially the entire length thereof, a base end side of which is connected to a main body operation unit, and a distal end portion of which is connected to at least an angle portion which can be bent vertically. A high hardness flexible portion having a low degree of flexibility in a bending direction for a predetermined length from the connection side to the main body operation portion, and a high hardness for a predetermined length from the connection side to the angle portion. A flexible portion having a higher degree of flexibility than the flexible portion is formed as a low-hardness flexible portion, and a transition portion between the high-hardness flexible portion and the low-hardness flexible portion is provided with the angle portion over a predetermined range. In the bending direction, the flexibility is different in the bending direction between the up-down direction and the left-right direction.

Here, in order to change the hardness of the flexible tube portion such as a high-hardness flexible portion, a low-hardness flexible portion, and a transition portion, any one of the bending portions of the flexible tube is bent. What is necessary is just to change the degree of directional flexibility. For example, a spiral tube,
The degree of flexibility can be changed by either the tubular net or an adhesive for fixing the tubular net to the outer skin layer. However, it is the simplest and most effective to cause the outer skin layer to exhibit the function of changing the degree of flexibility because of the presence of different regions. Therefore, the outer skin layer is formed of a high-hardness synthetic resin layer in the high-hardness flexible portion, and a low-hardness synthetic resin layer in the low-hardness flexible portion.
What is necessary is just to comprise so that the high-hardness synthetic resin layer side and the low-hardness synthetic resin layer side may be alternately protruded for every predetermined angle in the circumferential direction. It is desirable that the high-hardness synthetic resin layer and the low-hardness synthetic resin layer constituting the outer skin layer are formed of urethane resins having different rubber hardnesses.

The outer skin layer is formed by forming a high-hardness synthetic resin layer and a low-hardness synthetic resin layer in the form of a tube, respectively, and forming a tubular mesh body.
It is possible to adopt a configuration in which the end portions of both synthetic resin layers are abutted on each other and are adhered. In this case, it is preferable that the heat-shrinkable tube is further covered on the outer skin layer, and the heat-shrinkable tube is shrunk so as to be in close contact with the outer skin layer by heating. In addition, if a two-layer molding machine is used, molding can be performed so that the high-hardness synthetic resin layer and the low-hardness synthetic resin layer that constitute the outer skin layer are laminated on the tubular mesh body.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. First, FIG. 1 shows the entire configuration of an endoscope. As is clear from the figure, the endoscope is provided with the base end of the insertion section 20 connected to the main body operation section 21, and the light guide flexible section 22 extends from the main body operation section 21. The insertion tube 20 has a flexible tube portion 20a having a length substantially equal to the length of the flexible tube portion 2a from the side connected to the main body operation portion 21.
An angle portion 20b that can be bent in the vertical and horizontal directions by an angle operating means 23 provided on the main body operation portion 21 is provided at the distal end of the main portion 0a, and a distal end portion main body 20c is connected to the distal end of the angle portion 20b. ing. In this respect, there is no particular difference from the above-described configuration of the related art.

The flexible tube portion 20a has a configuration in which the degree of flexibility in the bending direction changes in the axial direction. That is, of the flexible tube portion 20a, the main body operation portion 2
1 is a high-hardness flexible portion 20aH
And a predetermined length from the side connected to the angle portion 20b is the low hardness flexible portion 20aS. Further, a hardness transition portion 20aT is provided between the high hardness flexible portion 20aH and the low hardness flexible portion 20aS. Here, although the high hardness flexible portion 20aH is flexible in the bending direction, it has a high resistance to bending, that is, a harder portion. The low hardness flexible portion 20aS is the same as the high hardness flexible portion 20aH. In comparison, it is a portion having a small resistance to bending, that is, a softer portion. As described above, although there is a difference in hardness in the bending direction between the high hardness flexible portion 20aH and the low hardness flexible portion 20aS, the difference is determined by the insertion resistance and the degree of bending of the insertion path. Further, it is appropriately set based on the purpose of use and the like.

Here, the hardness transition portion 20aT is a portion where the degree of flexibility with respect to bending changes in the circumferential direction. As shown in FIG. 2, when the angle portion 20b is configured to be able to bend in the vertical direction indicated by arrows U and D and the horizontal direction indicated by arrows R and L, the hardness transition portion 20
aT is such that one of the U and D directions or the R and L directions is hard and the other side is soft. For example, in the same figure, the angle 90 around the center lines U and D in the bending direction is shown.
The range of ° can be a soft portion S, and the range of 90 ° around the center lines R and L in the bending direction can be a hard portion H. In the case of a configuration in which the bending operation can be performed only in one of the up and down direction and the left and right direction, it is preferable that the bending operation is softer and the bending disabled direction is harder.

For example, as shown in FIG. 3, in the hardness transition portion 20aT, a high hardness flexible portion 20aH is provided on both left and right sides, and a low hardness flexible portion 20aS is provided on both upper and lower sides in a V-shape. It is formed so as to have a waveform so as to protrude in a shape. Alternatively, as shown in FIG. 4, the overhanging portion may be formed to have a band shape having a uniform width. In FIGS. 3 and 4, the hatched portions are portions where the high-hardness flexible portions 20aH project. When configured as a colonoscope, for example, approximately 100 to 400 from the distal end of the insertion portion 20 toward the proximal end side.
It is desirable that the low hardness flexible portion 20aS be used up to about mm and the axial length of the hardness transition portion 20aT be about 50 to 200 mm.

With this configuration, when inserting the insertion section 20 into a body cavity of a subject, for example, a colonoscope for a lower gastrointestinal tract along an insertion path, the distal end main body 20c is complicated. After the sigmoid colon portion, which is a curved path, is smoothly passed, and after the distal end main body 20c has passed through the sigmoid colon, the curved portion can be corrected so as to be substantially straight.

That is, when the distal end main body 20c of the insertion section 20 approaches a bent portion, the angle operating means 23 is operated to bend the angle section 20b, for example, in the upward direction (U direction), so that the path To bend in the bending direction. In this state, when the surgeon operates to grasp and push the proximal end of the flexible tube portion 20a by hand, the distal end portion main body 20c advances toward the bent portion. Since the distal end side of the flexible tube portion 20a is a low-hardness flexible portion 20aS, the low-hardness flexible portion 20aS advances into a bent portion in the sigmoid colon. Further, the hardness transition portion 20aT has a hard portion and a soft portion in the circumferential direction,
At the time of insertion into the sigmoid colon, the bending direction of the angle portion 20b is matched with the soft portion, that is, the side where the low-hardness flexible portion 20aS projects to the hardness transition portion 20aT. Proceeds smoothly to the curved part of the colon.

In this state, the entire insertion portion 20 is substantially 90 °
Operate to twist. Then, the hard portion of the hardness transition portion 20aT is oriented in the bending direction of the sigmoid colon. As a result, the hardness transition portion 20aT is straightened or at least corrected so that the bending angle is reduced. . Therefore, the sigmoid colon can be easily and reliably linearized approximately simply by twisting the insertion portion 20 and combining the operation with the insertion portion 20 to be pulled back. The insertion operability is improved. Further, the torsion angle of the insertion portion 20 is about 90 °, and such an amount of torsion can be easily performed by the operator, so that it is not necessary to change the posture of the subject lying sideways.

To form the low-hardness flexible portion 20aS, the hardness transition portion 20aT, and the high-hardness flexible portion 20aH on the flexible tube portion 20a from the distal end side, the flexible tube portion 20a is formed. It is most desirable to use two kinds of outer layers made of different materials. Therefore, for example, as shown in FIG. 5, the high hardness synthetic resin layer 30H constituting the high hardness flexible portion 20aH is formed of a urethane resin having a rubber hardness of JISA 75 ° to 90 °. Is JISA50 ° ~
The low-hardness synthetic resin layer 30S constituting the low-hardness flexible portion 20aS is formed of an 80 ° urethane-based resin in a tubular shape (however, the high-hardness synthetic resin layer 30H has a higher rubber hardness than the low-hardness synthetic resin layer 30H). Is higher). The high-hardness flexible portion 20aH and the low-hardness flexible portion 20aS form V-shaped overhangs at two locations at the joint therebetween.

The high-hardness resin layer 30H and the low-hardness resin layer 30S form a flexible tube portion 20a by joining V-shaped overhangs formed at their ends to each other. It is fitted into a tubular net to which an adhesive has been applied, and assembled so as to abut against each other accurately. Then, a sealing material is applied to a joint between the resin layers 30H and 30S, and a heat-shrinkable tube is further adhered, and then the heat-shrinkable tube is heated.

For example, as shown in FIG. 6, even when the composite molding machine 40 is used, a low hardness flexible portion 20aS, a hardness transition portion 20aT, and a high hardness The portion 20aH can be formed. That is, in FIG. 6, reference numeral 41 denotes a molding machine main body, and the molding machine main body 41 has a flexible pipe structure 4 in which the outer periphery of a spiral tube is covered with a tubular mesh body.
2 that constitutes the insertion passage 43 through which the second member 2 is inserted.
And an inner cylinder 45 and an outer cylinder 46. A molding die 47 is provided at a position upstream of the insertion passage 43 in the molding machine main body 41 so as to be connected thereto.

48a is a high-hardness resin, for example, rubber hardness J
A high-hardness resin supply unit to which an urethane resin of ISA 85 ° is supplied, and 48b is a low-hardness resin, for example, a rubber hardness of JIS.
A low-hardness resin supply unit to which a 75 ° urethane resin is supplied. These resin supply sections 48a and 48b communicate with supply passages 49a and 49b, respectively. The high-hardness resin supply passage 49a communicates with an annular supply passage 50 formed between the passage forming member 44 and the inner cylinder 45. The low-hardness resin supply passage 49b is formed between the inner cylinder 45 and the outer cylinder 46, and communicates with arc-shaped supply passages 51, 51 formed up and down by a predetermined angle. A position where the upper and lower arc-shaped supply passages 51 and the annular supply passage 50 join together is a joining portion 52.
The base of the discharge passage 53 is open at the junction 52. Therefore, the discharge passage 53 is formed by the passage forming member 44.
Is a passage formed by a conical gap formed between the conical portion at the tip of the dies and the forming die 47, and the tip is a thin annular discharge port 54.

In order to laminate the outer skin layer on the outer peripheral surface of the flexible tube structure 42 by using the composite molding machine 40 having the above structure, an adhesive is previously applied to the entire outer surface of the flexible tube structure 42. After being uniformly applied, the flexible tube structure 42 is fed into a passage 43 provided in the composite molding machine 40 in the direction of the arrow in FIG. Initially, of the resin supply sections 48a and 48b, the high-hardness resin supply section 48a for supplying the high-hardness resin is supplied at a predetermined pressure in a state where the high-hardness resin is melted. Does not supply resin. As a result, only the high-hardness resin flows into the discharge passage 53, and is discharged from the discharge port 54. As a result, only the high-hardness resin is laminated on the flexible tube structure 42.

In this flexible tube structure 42, after the high-hardness resin is supplied by the length corresponding to the high-hardness flexible portion 20aH, the resin is also supplied from the low-hardness resin supply portion 48b side. At this time, the supply pressure of the resin from the low-hardness resin supply section 48b is higher than the supply pressure of the high-hardness resin. Thus, the low-hardness resin supplied from the low-hardness resin supply unit 48b reaches the junction 52 from the arc-shaped supply path 51. As described above, the low-hardness resin is supplied only from the two upper and lower locations from the arc-shaped supply path 51, and since the supply pressures are different, and there is also a difference in the viscosity between the two resins. 2
The types of resins are not substantially mixed, and the low-hardness resin initially has only a very narrow width in the upper and lower two places.
4 is discharged in a layered state. Then, the supply pressure of the low-hardness resin from the low-hardness resin supply unit 48b is kept constant, and the supply pressure of the high-hardness resin from the high-hardness resin supply unit 48a is gradually reduced. As a result, the low-hardness resin is initially supplied to the flexible tube structure 42 only in a narrow range above and below,
The width continuously increases. When the molding corresponding to the length of the hardness transition portion 20aT in the flexible tube portion 20a is completed, the supply of the resin from the high-hardness resin supply portion 48a is shut off. Thereby, the flexible tube structure 4
2, the low-hardness resin is laminated over the entire circumference.

With the above construction, the outer skin layer formed on the flexible tube structure 42 becomes a substantially uniform layer, and as shown in FIG.
0aH is on the left and right sides, and the low-hardness flexible portion 20aS
The hardness transition portions 20aT can be formed on both upper and lower sides so as to protrude in a V-shape with respect to each other.

[0026]

As described above, the present invention provides a difference in flexibility in the bending direction in the axial direction of the flexible tube as well as the circularity between the high hardness flexible portion and the low hardness flexible portion. Since a hardness transition portion having a difference in hardness in the circumferential direction is formed, the operation of inserting the insertion portion while straightening a curved path of the insertion path while straightening is more smoothly and easily, and moreover, It has effects such as being able to be performed in a short time.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an endoscope showing one embodiment of the present invention.

FIG. 2 is an explanatory view showing a bending portion of an angle portion in an insertion portion and a flexibility portion in a bending direction of a hardness transition portion of a flexible tube portion.

FIG. 3 is a diagram showing a first form of a hardness transition portion in a flexible tube portion.

FIG. 4 is a view showing a second mode of the hardness transition portion in the flexible tube portion.

FIG. 5 is a development view of the outer skin layer when the hardness transition portion is formed by the outer skin layer and formed by two types of cylindrical members.

FIG. 6 is a cross-sectional view of a composite molding machine for forming a hardness transition portion with a skin layer and laminating the skin layer to a flexible tube structure by a molding means.

FIG. 7 is an explanatory diagram showing the entire configuration of the endoscope.

FIG. 8 is an explanatory view showing a configuration of a flexible tube according to a conventional technique.

FIG. 9 is an explanatory view showing a state where the insertion portion is inserted into the sigmoid colon.

[Explanation of symbols]

Reference Signs List 20 insertion portion 20a flexible tube portion 20aH high hardness flexible portion 20aS low hardness flexible portion 20aT hardness transition portion 20b angle portion 20c tip main body 21 main body operation portion 30H high hardness resin layer 30S low hardness resin layer 40 composite molding machine

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koichi Kamata 1-324 Uetake-cho, Omiya City, Saitama Prefecture Fuji Photo Optical Co., Ltd. (72) Inventor Tomoyuki Ishida 1-324 Uetake-cho, Omiya City, Saitama Fuji Photo F term in Koki Co., Ltd. (reference) 2H040 BA21 DA14 4C061 AA04 BB01 CC00 DD03 FF24 FF26 FF29 FF30 JJ01 JJ06

Claims (5)

[Claims] 1. A tubular structure that is flexible in a bending direction is covered with a tubular mesh body, and an outer skin layer is laminated on the tubular mesh body, and has flexibility in a bending direction over substantially the entire length thereof. A flexible tube of an endoscope having a proximal end connected to the main body operating section and a distal end connected to at least an angle section capable of being bent in a vertical direction, wherein a predetermined length from a side connected to the main body operating section is provided. The high rigidity flexible portion having a low degree of flexibility in the bending direction has a low degree of flexibility higher than the high hardness flexible portion for a predetermined length from the connection side to the angle portion. In the transition between the high-hardness flexible portion and the low-hardness flexible portion, the bending portion has a bending direction in a vertical direction and a horizontal direction in a bending direction of the angle portion over a predetermined range. The endoscope is characterized in that it has a configuration in which the hardness is changed with different flexibility. Shiwakan. 2. The outer skin layer has no high-hardness synthetic resin layer in the high-hardness flexible portion, has no low-hardness synthetic resin layer in the low-hardness flexible portion, and has a circumferential direction in the hardness transition portion. 2. The flexible tube for an endoscope according to claim 1, wherein the high-hardness synthetic resin layer and the low-hardness synthetic resin layer are formed so as to alternately protrude at predetermined angle intervals. 3. The endoscope according to claim 2, wherein the high-hardness synthetic resin layer and the low-hardness synthetic resin layer forming the outer skin layer are formed of urethane resins having different rubber hardnesses. Flexible tube. 4. The outer skin layer is formed by forming the high-hardness synthetic resin layer and the low-hardness synthetic resin layer in the form of a tube, respectively, and bringing the ends of both synthetic resin layers into contact with the tubular mesh body. 4. The flexible tube for an endoscope according to claim 3, wherein the heat-shrinkable tube is attached to the outer periphery of the flexible tube. 5. The structure according to claim 3, wherein said high-hardness synthetic resin layer and said low-hardness synthetic resin layer constituting said outer skin layer are laminated on said tubular net using a composite molding machine. Endoscope flexible tube.