JPH0793920B2 - Endoscope - Google Patents

Description

TECHNICAL FIELD The present invention relates to an endoscope in which a bending tube portion of an insertion portion is forcibly bent.

[Prior Art] In general, an endoscope is provided with a curved tube portion at its insertion portion in order to perform necessary observation and to enhance insertability, and the curved tube portion is forced by remote operation from a hand operation portion side. Can be curved.

By the way, the bending tube portion is configured such that a plurality of bending pieces are arranged in a line, and adjacent bending pieces are pivotally attached to each other so that the bending pieces can be bent as a whole. (Public Publication No. 60-41207). Then, by pulling the operation wire inserted through the insertion portion, it is bent toward the pulling side.

Further, when the bending wire portion is bent by pulling the operation wire, the moments applied to the respective piece portions are compared, and the bending piece located closer to the distal end side has a smaller bending moment and conversely the proximal end side has a larger moment. Therefore, the bending tube portion has a characteristic of starting to bend from the base end side.

However, in actual use, it is desirable to start bending from a portion near the tip side. For example, with a direct-viewing type gastroscope, it is necessary to view the entire stomach from the front,
For this purpose, it is desirable that the portion near the tip side be curved. However, in the above-mentioned conventional method, since the bending is preferentially bent from the proximal end side of the bending tube portion, in a bending state where the maximum bending angle is not reached, only the proximal end side portion is largely bent, and the distal end side is hardly bent. Becomes For this reason, the tip rigid portion is substantially lengthened, and the distance between the tip of the endoscope insertion portion and the stomach angle cannot be appropriately set.

Further, in the endoscope for large intestine, when the bending tube portion bends so as to draw a substantially large arc, the bending portion advances along the intestinal wall when the insertion portion is pushed, so that the insertability is improved, In the case of the system type, the base end side begins to partially bend, which impairs the insertability.

On the other hand, in order to solve these inconveniences, the above-mentioned J.K.
The one disclosed in Japanese Patent No. 1207 has been proposed. In order to guide the operation wire, a spacer is provided between the wire guides provided inside the bending piece to regulate the bending action and obtain a desired bending state.

[Problems to be Solved by the Invention] However, in the assembly in the above method in which a spacer is provided to regulate the bending action, the spacer is mounted in advance before loading the built-in object, and after that, the built-in object is loaded and A mesh tube should be fitted around the outer circumference of the bridge. The adjustment of the bending characteristic is performed without connecting the built-in object and the mesh tube and only by connecting the bending pieces.

However, the case where the bending piece is simply connected and the case where the built-in object is loaded and the mesh tube is fitted differ depending on the variation in the size of the piece and the like.

For this reason, if readjustment is desired after assembly, the number of spacers and the length of the spacers must be changed, so it is necessary to remove the operation wire once. That is, it is necessary to pull out all the built-in components from the curved tube portion.

However, this is practically impossible because there is a risk that the fiber bundle is broken. That is, the above-mentioned system cannot readjust the bending characteristic. Therefore, it may happen that the bending properties in the finished state are not the best.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an endoscope capable of setting a bending characteristic in a state of a bending tube portion covered with a mesh tube and having a built-in object inserted therein. .

[Means and Actions for Solving Problems] In the present invention, a plurality of bending pieces are arranged in a line, adjacent bending pieces are rotatably connected to each other, and the outer periphery of the bending pieces is covered with a covering member to bend the bending tube portion. In the endoscope in which the bending tube portion is bent by an operation wire, a bending restriction for suppressing the bending action corresponding to the position between the bending pieces to be restricted from the outside of the covering member. Means are provided.

According to the above configuration, the bending characteristic can be set in a state close to a finished product without disassembling the bending tube portion or taking out the built-in object. Therefore, the best bending characteristic can be easily obtained.

[Embodiment] FIGS. 1 to 3 show an embodiment of the present invention. FIG. 3 shows the entire endoscope according to the embodiment. The endoscope 1 is composed of an operation section 2, an insertion section 3 and a light guide cable 4. The insertion section 3 is composed of a flexible tube section 5, a bending tube section 6 and a tip section 7, and the bending tube section 6 is forcibly bent as described later.

Further, a lateral bending angle knob 8 and a vertical bending angle knob 9 are provided on the position side surface of the operation portion 2 so as to vertically overlap with each other on the same axis. Further, a first fixing lever for fixing the left and right curved angle knobs 8 on the uppermost part.
11 is provided, and a second fixing lever 12 for fixing the vertical bending angle knob 9 is provided at the lowermost portion. Each of the angle knobs 8 and 9 is connected to an operating mechanism (not shown) incorporated in the operating section 2, and drives the operating mechanism to push and pull an operating wire described later. Further, the first fixing lever 11 releases the left and right bending angle knob 8 at the position shown by the solid line in FIG. 4, and also at the position also shown by the dotted line, the left and right bending angle knob 8.
Is designed to be fixed. On the other hand, the second fixed lever
Reference numeral 12 similarly releases the vertical bending angle knob 9 at the position shown by the solid line in FIG. 4 and fixes it at the position shown by the dotted line. A fixed position indicator 13 is provided on the side surface of the operation portion 2 corresponding to the fixed position of the second fixing lever 12, and a released position indicator 14 is provided on the side surface of the operation portion 2 corresponding to the release position. It is provided. Further, a fixed direction display 15 and a release direction display 16 are displayed near the respective displays 13 and 14. In addition, each fixed lever 11,12
Are configured so that their orientations match in their fixed positions and also in their release positions. That is, when both the fixed levers 11 and 12 are rotated in the counterclockwise direction, the braking mechanism thereof operates. Also, the left and right bending angle knobs 8 are installed so as to be within a range of 40 mm to 60 mm from the side surface (the surface on which the palm part of the gripping hand contacts) opposite to the side surface on which the angle knobs 8 and 9 are provided. There is. With this installation, the right and left bending angle knob 8 can be easily operated by the hand holding the operation portion 2.

On the other side surface of the operation unit 2, an air / water supply operation button 15 and a suction operation button 16 are provided.

On the other hand, the bending tube portion 6 of the insertion portion 3 is constructed as shown in FIG. The core material of the bending tube portion 6 is formed by arranging a plurality of bending pieces in a position row in the longitudinal axis direction of the insertion portion 3 and rotatably contacting adjacent ones.
In this case, all the bending pieces are not the same, and the most distal bending piece 21, the four-direction bending piece 22, the two-direction bending piece 23, and the proximal end bending piece 24 are sequentially connected from the tip side. The tip end bending piece 21 is fixedly attached to the tip end portion 7, and the proximal end bending piece 24 is connected to the tip end of the flexible tube 5. Further, a mesh tube 25 as a first covering member is fitted on the outer circumference of each bending piece 21, 22, 23, 24, and further, an elastic tube as a second covering member made of rubber or the like is formed on the outer circumference thereof ( It is covered with 26). The distal end of the elastic tube 26 is fitted on the outer periphery of the base end portion of the distal end portion 7, and a fixing thread 27 is wound around the outer periphery and tightened, and the fixing thread 27 is fixed with an adhesive 28.
Further, the proximal end of the elastic tube 26 is made to abut against the distal end of the outer tube 29 of the flexible tube portion 5, and further, the fixing thread 31 is wound around both the abutting ends of the elastic tube 26 and the outer tube 29 and the fixing thereof is performed. The yarn 31 is fixed with an adhesive 32. Although the fixing yarns 27 and 31 and the adhesives 28 and 32 are drawn in a large size in the drawing, they are actually much smaller than this. Further, since the elastic tube 26 and the outer tube 29 contract when tightening the thread, the outer diameter becomes equal to that of the other insertion portion 3.

Further, the distal ends of the operation wires 33, 34, 35, 36 located vertically and horizontally are attached to the most distal bending piece 21. The operation wires 33, 34, 35, 36 are formed on the inner surface portions of the four-way bending piece 22 and the two-way bending piece 23, but are provided on the guide hole 37 and the guide tube 28 disposed inside the flexible tube portion 5. It is inserted and guided. The proximal ends of the operation wires 33, 34, 35, 36 are connected to the operation mechanism in the operation section 2. The operation wires 33, 34, 35, 36 are alternately pushed and pulled by this operation mechanism in a combination of up and down or left and right.

Further, as shown in FIG. 1, an objective lens 41 and a solid-state image sensor 42 are provided at the tip portion 7, and a signal cable 43 is connected to the solid-state image sensor 42. In addition to the signal cable 43, the light guide fiber 4 is provided in the insertion portion 3.
4, built-in objects such as the water supply tube 45, the air supply tube 46, the forceps channel tube 47 are inserted.

Further, in the mesh tube 25 of the bending tube portion 6 having the above-mentioned configuration, for example, a portion 47 corresponding to a position between the proximal side bending piece 24 and the two-way bending piece 23 is coated with an ultraviolet curable adhesive to cure it. Bending control means is provided. Then, the bending regulating means suppresses the bending action of the portion 48, and sets the bending characteristics of the entire bending tube portion 6.

Next, a method of providing the above-mentioned bending regulation means will be described. First, assembling the curved tube portion 6 without the elastic tube 26,
Operation wire on the upper side with built-in components
33, the bending pieces 21, 22, 23, 24 hit each other, and the maximum bending angle (hereinafter referred to as the maximum bending angle) is the bending pieces.
It depends on the machining accuracy of 21,22,23,24 and the degree of beaming of the mesh tube 25 that regulates their axial displacement. For example, if the maximum bending angle should be set to 210 °, 220 ° or 230
° There will be variations. Further, this variation differs for each endoscope 1 even in the same model.

Therefore, for example, when the actual maximum bending angle is 220 °, the portion 48 of the mesh tube 25 corresponding to the position between the bending piece 24 on the most proximal side and the bidirectional bending piece 23 adjacent thereto is UV-cured. Apply a mold adhesive and cure it. The portion 48 is formed wider than the width of the bending pieces 23, 24 so as to extend to the portions of the bending pieces 23, 24. By providing the bending restricting means in this manner, the maximum bending angle is reduced to, for example, 215 ° which is slightly larger than the desired angle in consideration of the influence of the elastic tube 26.

After this, the elastic tube 26 is fitted, and both ends of the elastic tube 26 are fixed.
Tighten with 7,31 and harden with glue 28,32. Furthermore, the position of a bending operation wire stopper (not shown) provided in the operation portion 3 is adjusted to finally set the bending angle to a desired 210 °.

When the maximum bending angle of the bending tube portion 6 is larger than 230 °, in addition to the above portion 47, the adjacent two-way bending pieces 23, 23
An ultraviolet curable adhesive is also applied to the portion 49 of the mesh tube 25 corresponding to the position between them, and this is cured. Then, similarly to the above, the bending angle may be set to be slightly larger than the desired angle.

Then, when the maximum bending angle of the bending tube portion 6 is larger than the required bending angle, the bending side length is effectively shortened by fixing the proximal portion by the bending regulating means. Therefore, the effective length of the tip rigid part is shortened,
The angle of the stomach becomes easier to see.

A thermosetting adhesive may be used for the bending means, but since the ultraviolet curing adhesive is used particularly in the above-mentioned embodiment, it is not necessary to apply heat, and the light guide fiber 44 or the like is not adversely affected. Moreover, it cures in a short time.

Further, when the adhesive is applied to the portions 48 and 49 of the mesh tube 2, the proximal end bending piece 24 and the two-way bending piece 23 are contacted with each other within a range that does not adversely affect the movement of the operation wire 33 within the guide hole 37. An adhesive may be poured into the contact portion (connecting portion) and fixed at the same time.

Further, although the bending restricting means of the above-described embodiment is configured such that the adhesive is applied to the mesh tube 25, a heat shrinkable tube may be fitted around the mesh tube 25 to cause heat shrinkage. Note that heat shrinking with hot air from a dryer damages the ride guide fiber 44 and the like, so it is advisable to bring a soldering iron or the like into contact with the heat shrinkable tube for shrinking. Alternatively, the above-mentioned adhesive and heat-shrinkable tube may be used as the bending regulation means.

Alternatively, the bending pieces may be rotatably connected using shafts.

Further, the four-way bending piece 22 is provided on the distal end side of the bending tube portion 6 of the above embodiment.
And the two-way bending piece 23 is arranged on the proximal side of the base, so that the left-right direction bends at a portion closer to the tip. Furthermore, 4
The adhesive for bending control is less likely to enter the inside of the bending piece 23 as compared with the case where the direction bending pieces 22 are arranged on the proximal side of the hand.

Note that the curvature may be regulated by soldering instead of bonding when the net tube is covered without inserting the built-in object.

Further, when the endoscope is a large intestine scope, the intermediate portion of the bending tube portion 6 may be fixed appropriately.

Further, FIG. 4 shows another example of the bending restricting means, in which the fixing thread 51 is wound around the outer circumference of the elastic tube 26 as the second covering member and the thread 51 is fixed with the adhesive 52. Therefore, the bending action is suppressed. Further, since the wound fixing thread 51 is of the type that is fixed by the adhesive 52, the thread 51 only needs to exhibit the anchoring action of the adhesive 52, and therefore may be wound more loosely than the fixing threads 27 and 31. . The fixing thread 51 may be the same as the fixing thread 31. Further, a material different from that of the fixing threads 27 and 31 may be used.

Further, the bending restricting means in the present invention may be one in which a heat-shrinkable tube is fitted on the outer circumference of the elastic tube 26 at a position where it is necessary to suppress the bending action to restrict the bending.

[Effects of the Invention] As described above, according to the configuration of the present invention, the bending characteristic can be set in the state of the bending tube portion in which the mesh tube is fitted and the built-in object is inserted. In other words, the bending characteristics can be set in a state close to a finished product without disassembling the bending tube portion or taking out the built-in object. Therefore, the best bending characteristic can be easily obtained without damaging the built-in object.

[Brief description of drawings]

FIG. 1 is a side sectional view of an insertion portion according to an embodiment of the present invention,
FIG. 2 is a sectional view taken along the line II-II in FIG. 1, FIG. 3 is a perspective view of the same embodiment, and FIG. 4 is a sectional view of an essential part in another embodiment. 1 ... Endoscope, 5 ... Flexible tube, 6 ... Curved tube, 7 ...
… Tip part, 21 …… Cutting edge bending piece, 22 …… Four-way bending piece,
23 …… 2-way bending piece, 24 …… Bend end bending piece, 25 …… Net tube, 26 …… Elastic tube, 47,48 …… Part, 51 …… Thread, 52 ……
adhesive.

Claims (1)

[Claims] 1. A bending tube portion having a plurality of bending pieces arranged in a line, adjacent bending pieces being rotatably connected to each other, and having an outer periphery covered with a covering member. In the endoscope in which the distal end of the operation wire inserted through the inner portion is connected to the distal end side of the bending tube portion, and the bending operation is performed by advancing / retreating the operation wire, the bending portion is intended to be regulated from the outside of the covering member. An endoscope characterized in that a bending regulating means for suppressing a bending action is provided corresponding to a position between the pieces.