JP2004081891A - Endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope which makes full use of the function of a hardness variable means prepared within a flexible tube and can obtain successful followability by carrying handy operation to an apex end. <P>SOLUTION: A coil pipe 32 is set along a longitudinal direction on the side of an inner wall of a flexible tube 12. A central position of the coil pipe 32 is located on each wall side 29a of an UP side sector within the region from a symbol C to a symbol D, or a DOWN side sector within the region from a symbol E to a symbol F respectively, when an area within a spiral pipe 29 is split into four as a dashed line shows. For this reason, the spiral pipe 29, a screen pipe 30, and a shell 31 located on the inside of the circular arc of a central axis of this flexible tube 12 curve while they are shrunk, and the spiral pipe 29, the screen pipe 30, and the shell 31 located on the outside of the circular arc of the central axis curve while they are stretched when the flexible tube 12 in a tube-like manner which consists of the spiral pipe 29, the screen pipe 30, and the shell 31 is inflected as a simple body. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to an endoscope in which the hardness of the distal end side of a flexible tube constituting an insertion portion is adjustable.

In recent years, by inserting an elongated insertion portion into a body cavity, an endoscope that can observe an inspection target site in the body cavity without necessitating an incision and perform a therapeutic treatment using a treatment tool if necessary. Has become widely used.

The insertion portion of the endoscope has flexibility so that it can be inserted into a bent insertion path. However, by providing flexibility, the distal end side of the insertion portion near the insertion portion can be operated. There is a problem that the directionality is not determined, and it is difficult to smoothly insert the target portion.

To cope with this problem, Japanese Unexamined Utility Model Publication No. 3-43802, for example, discloses that an endoscope is provided with a variable hardness means (or a variable flexibility means) comprising a coil pipe and a wire inside an endoscope. There is disclosed an endoscope in which a surgeon performing a simple operation adjusts the flexibility of an insertion portion to facilitate insertion into a curved path.
Japanese Utility Model Publication No. 3-43802

However, the flexibility of the flexible tube is changed in advance between the distal portion and the proximal portion, for example, the flexibility of the proximal portion is set to be harder than the distal portion. If provided, it is possible to further harden the hardness of the hand side portion that is set to be harder in advance, but it is possible to adjust the hardness of the more flexible portion on the distal end side to be harder. Did not. For this reason, since the highly flexible distal end portion remains in a soft state, for example, it is assumed that the observation is performed by transanally inserting the rectum, sigmoid colon to the deep part such as the descending, transverse and ascending colons. However, there is a problem that the operator's hand operation is not sufficiently transmitted to the distal end portion, and good followability cannot be obtained, so that the desired operation cannot be performed, and the operator cannot smoothly insert the target portion.

Further, when the distal end portion of the hardness changing means is disposed at substantially the same position as the hardness changing portion where the hardness of the flexible tube changes, when the hardness changing means is in the hard state, the hardness changing portion of the flexible tube changes. In addition to the hardness of the flexible tube, the hardness of the hardness changing means becomes harder, and the hardness of the hardness changing portion becomes sharply harder than the flexibility on the tip side of the hardness changing portion. However, there is a possibility that the bent portion may be bent in the vicinity of the hardness changing portion to deteriorate good insertability.

The present invention has been made in view of the above circumstances, and while emphasizing the flexibility of the flexible tube, the function of the hardness variable means provided in the flexible tube is utilized to the maximum extent to allow the user to perform a hand operation. It is an object of the present invention to provide an endoscope that can be transmitted to a distal end portion and obtain good followability.

The endoscope according to the present invention is provided with a hardness changing means for changing the flexibility of the flexible tube provided along the longitudinal axis inside a flexible tube connected to the curved portion constituting the insertion portion, Operating means for adjusting the hardness of the hardness variable means to change the hardness of the flexible tube, the endoscope capable of bending the distal end of the insertion portion in a predetermined direction,
In a configuration in which the end of the insertion section is bent by the bending operation so as to be directed upward or downward on the monitor screen as the vertical direction of the endoscope,
The hardness varying means is provided on an upper inner wall side or a lower inner wall side in a vertical cross section of the flexible tube.

According to this configuration, when the operating means is operated to change the hardness of the flexible tube, the hardness of the flexible tube on the upper side or the lower side mainly changes.

ADVANTAGE OF THE INVENTION According to this invention, while making much of the flexibility of a flexible tube, the function of the hardness variable means provided in the flexible tube is utilized to the fullest, and the hand operation is transmitted to the distal end portion to achieve good follow-up. It is possible to provide an endoscope capable of obtaining the desired characteristics.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 7 relate to a first embodiment of the present invention, FIG. 1 is an explanatory view showing a schematic configuration of an electronic endoscope, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. FIG. 4 is a schematic view illustrating an arrangement position in the flexible tube, FIG. 4 is a sectional view taken along line BB of FIG. 3, and FIG. 5 is a distance from an end of a scope of an endoscope provided with a flexible tube having a hardness changing portion and hardness. FIG. 6 is a diagram showing the relationship between the distance from the end of the scope of an endoscope having a flexible tube having a hardness change region and the hardness, and FIG. It is a figure showing the insertion state at the time of insertion.

As shown in FIG. 1, an electronic endoscope (hereinafter, referred to as an endoscope) 1 according to a first embodiment of the present invention has an elongated and flexible insertion portion 2 and a rear end of the insertion portion 2. An operation unit 3 is provided on the end side, and a universal cable 4 extending from a side of the operation unit 3 is provided. The universal cable 4 includes a light source unit that supplies illumination light, which is an external device of the endoscope 1, and a signal processing unit that processes an electric signal transmitted from the endoscope 1 (not shown). Is provided with a connector 4a. The video signal output from the control device is displayed on a screen of a monitor (not shown).

The insertion portion 2 has a rigid distal end portion 10 on the distal end side, and a bendable curved portion 11 is continuously provided on the rear side adjacent to the distal end portion 10, and further has flexibility behind the curved portion 11. The flexible tube 12 in the form of a tube is continuously provided.

The distal end portion 10 has a distal end main body 13 in which a rigid member is formed in a substantially cylindrical shape. The distal end main body 13 has a through hole for a forceps channel formed in parallel with the longitudinal direction of the insertion portion 2. 14 and an observation through-hole 15 are provided.

A connecting tube 16 is built in the through hole 14 for the forceps channel, and a flexible forceps for forming a forceps channel 17 at a rear end portion of the connecting tube 16 protruding from a rear end surface of the distal end body 13. The distal end of the channel tube 18 is connected. The forceps channel tube 18 is inserted into the insertion section 2, guided into the operation section 3, and has a rear end communicated with a forceps port 19 provided in the operation section 3.

An objective lens system 20 is provided at the tip of the observation through-hole 15, and a solid-state imaging device 21 is provided at an image forming position of the objective lens system 20. A signal cable 22 for transmitting input / output signals is connected to the solid-state imaging device 21. The signal cable 22 is inserted through the insertion section 2 and further connected to the electrical contact 4b provided on the connector 4a via the operation section 3 and the universal cord 4.

A light guide connector 24 formed such that illumination light emitted from a light source unit (not shown) to illuminate an observation site is incident on an end of a light guide 23 inserted through the endoscope insertion unit 2 to the connector 4a. Is provided. The light guide 23 passes through the inside of the universal cable 4, the operation section 3, and the insertion section 2, and has a distal end disposed in a light guide through hole (not shown) provided in the distal end body 13.

A plurality of substantially annular joint pieces 26,..., 26 are rotatably connected to each other in the bending section 11 in the longitudinal direction of the insertion section 2. Is fixed to the rear end of the distal end body 13 and the joint piece 26e located at the rearmost end of the annular connecting pipe 27 provided at the distal end of the flexible tube 12. It is fitted and fixed to the tip. The bending portion 11 connecting the plurality of joint pieces 26,..., 26 is bent in, for example, up / down / left / right directions by operating a bending operation knob (not shown) provided on the operation portion 3.

接 続 An angle wire guide 41 (see FIG. 2) fixed to the rear end of the distal end body 13 and formed by a metal coil pipe is fixed to the connection pipe 27. An angle wire 42 (see FIG. 2) formed of a stranded wire or the like that is pulled and relaxed by operating a bending operation knob provided on the operation unit 3 is inserted into the angle wire guide 41. I have. That is, by operating the bending operation knob, the angle wire 42 is pulled and relaxed to bend the bending portion 11 so that the distal end portion 10 located in front of the bending portion 11 is directed in a desired direction. Has become. The plurality of joint pieces 26,..., 26 that constitute the curved portion 11 are covered with a soft outer skin 28.

可 撓 The flexible tube 12 is composed of a spiral tube 29, a mesh tube 30, and a skin 31 in this order from the inside. A coil pipe 32 is provided along the longitudinal direction on the inner wall surface side of the spiral tube 29 as a hardness changing means for changing the flexibility (hereinafter, referred to as hardness) of the flexible tube 12. A hardness adjusting wire 33 serving as an operating means for adjusting the hardness of the flexible tube 12 to a desired hardness is inserted through the inside of the coil pipe 32.

(4) At the tip of the coil pipe 32, a middle part of the hardness adjusting wire 33 is firmly fixed by a fixing member such as a solder 35. The distal end of the hardness adjusting wire 33 protruding from the distal end of the coil pipe 32 and extending further in the distal direction is firmly fixed to a part of the connection pipe 27 with a braze 35 or the like. On the other hand, the proximal side of the coil pipe 32 is firmly fixed to the rear end cap 36 with a wax 35 or the like.

That is, the hardness adjusting wire 33 is movable (unfixed state) with respect to the coil pipe 32 except that the middle portion is fixed at the tip end of the coil pipe 32 by the wax 35.

The end of the hardness adjusting wire 33 extending from the proximal end of the coil pipe 32 is connected to an operating mechanism provided in the operating section 3, and is operated by operating this operating mechanism. By pulling the coil 33, the coil pipe 32 is compressed, and the rigidity of the coil pipe 32 in the bending direction is increased, thereby increasing the hardness of the flexible tube 12 from the soft state where no load is applied. It can be adjusted to any hardness up to the hardened state.

The upward direction in FIG. 2 indicates the UP direction of the endoscope 1, and the UP direction of the endoscope 1 is obtained by operating the upward bending knob provided on the operation unit 3. Is the direction in which the tip 10 bends. It corresponds to the upward direction (anti-gravity direction) on the monitor screen. As shown in the figure, the coil pipe 32 and the hardness adjusting wire 33 are arranged on the UP direction side in the endoscope 1. Reference numeral 43 denotes an air supply tube that constitutes an air supply conduit, and reference numeral 44 denotes a water supply tube that constitutes a water supply conduit. The distal ends of both tubes are provided on the distal end body 13 for air supply / water supply. It communicates with a hole (not shown).

First, the arrangement position of the coil pipe 32 configured as described above in the cross-sectional direction of the flexible tube 12 will be specifically described.
As shown in FIG. 3, the distal end of the coil pipe 32 provided along the longitudinal direction on the inner wall side of the flexible tube 12 of the endoscope 1 is fixed to the hardness adjusting wire 33 with the wax 35 as described above. The distal end of the adjustment wire 33 extending from the distal end surface of the coil pipe 32 is fixed to the connection pipe 27. On the other hand, the proximal side of the coil pipe 32 is fixed to a rear end base 36 with a wax 35. Further, the respective distal ends of the helical tube 29, the mesh tube 30, and the outer cover 31 constituting the flexible tube 12 are firmly fixed integrally to the rear end of the connection tube 27, and the rear ends of the respective tubes are connected to the rear. It is firmly and integrally fixed to the tip of the end cap 36 to form a tube.

As shown in FIG. 4, the center position of the coil pipe 32 provided on the inner wall surface side of the spiral tube 29 constituting the flexible tube 12 is when the inside of the spiral tube 29 is divided into four as indicated by broken lines. , The UP side area in the range from the symbol C to the symbol D, or the DOWN side area in the range from the symbol E to the symbol F are arranged on the wall surface side 29a.

For this reason, when the flexible tube 12 composed of the spiral tube 29, the mesh tube 30, and the outer skin 31 is bent by itself, the portion of the flexible tube 12 located inside the circular arc from the center axis of the flexible tube 12. The spiral tube 29, the mesh tube 30, and the outer skin 31 are curved while shrinking, and the portions of the spiral tube 29, the mesh tube 30, and the outer skin 31 located outside the circular arc from the central axis are curved while extending.

Here, for example, the hardness adjusting wire 33 provided inside the flexible tube 12 is pulled to compress the coil pipe 32 to make it hard. Then, in this state, the flexible tube 12 is bent in the UP direction. Then, the portion located inside the circular arc from the central axis of the spiral tube 29, the mesh tube 30, and the outer cover 31 located on the UP side of the endoscope 1 tries to shrink, but as shown by the solid line in FIG. The spiral pipe 29, the mesh pipe 30, and the outer skin 31 curb while suppressing the shrinkage of the helical tube 29, the mesh tube 30, and the outer skin 31 by the coil pipe 32 in the hard state arranged in the above.

On the other hand, when the coil pipe 32 is arranged on the DOWN side as shown by a two-dot chain line in FIG. , The portion located outside the circular arc from the central axis of the mesh tube 30 and the outer cover 31 tends to extend, but the coiled tube 32, the mesh tube 30 and the outer cover 31 are hardened by the coil pipe 32 in the DOWN side region. Curves while suppressing the extension of the part.

Next, the arrangement position of the coil pipe 32 configured as described above in the longitudinal direction of the flexible tube 12 will be specifically described.
As shown in FIG. 5, the flexible tube 12 of the endoscope 1 used in the present embodiment is a flexible tube having a hardness changing portion 34a by connecting two separate outer skins 31a and 31b having different hardnesses. 12A and a flexible tube 12B composed of an outer skin 31c having a hardness change area 34b in which hardness changes gradually as shown in FIG.

The flexible tube 12A shown in FIG. 5 has a soft flexible portion that covers a soft soft skin 31a that forms up to about 50 cm from the distal end of the scope, and a soft but soft skin 31a that forms from this 50 cm to the hand side. And a hard flexible portion coated with a hard outer skin 31b having a slightly higher hardness. That is, the hardness is set to be harder on the side of the hand than on the side of the distal end with the boundary of the hardness change portion 34a near 50 cm from the distal end of the scope. Then, the distal end portion of the coil pipe 32 inserted into the inside of the flexible tube 12A is positioned on the distal end side from the hardest portion on the proximal end side of the flexible tube, and the hardness change portion 34a is approximately 30 cm from the distal end of the scope. It is disposed on the soft flexible portion closer to the distal end portion 10.

As shown in the graph of FIG. 5, when the hardness adjusting wire 33 inserted through the inside of the coil pipe 32 is not pulled, the hardness of the flexible tube 12 is represented by a solid line in the soft state (the coil pipe 32 is not loaded). It is set as shown. In the hard state where the hardness adjusting wire 33 is pulled to the maximum and the coil pipe 32 is compressed most (the state where the maximum load is applied to the coil pipe 32), the hardness of the flexible tube 12 is as shown in FIG. It becomes as shown by the broken line. That is, the hardness of the flexible tube 12 changes from the solid line to the range shown by the broken line by appropriately pulling the hardness adjusting wire 33.

た め Since the distal end of the coil pipe 32 is not located closer to the distal end than the portion 30 cm from the distal end of the scope, it is not possible to adjust the hardness of the soft flexible portion within a range of 30 cm from the distal end of the scope. The portion indicated by the solid line having the lowest hardness on the tip side is referred to as the softest state portion S, and the portion indicated by the solid line having the highest hardness on the hand side is referred to as the hardest state portion H.

The flexible tube 12B shown in FIG. 6 includes an outer skin 31c having a hardness change region 34b in which the hardness gradually changes from the softest state to the hardest state from about 34 cm to about 50 cm from the end of the scope. . In other words, in this flexible tube 12B, the range from the distal end of the scope to around 34 cm is the softest flexible portion S which is the softest state portion S. A hardness change region 34b that gradually changes to the hardest state is a hard flexible portion in which the range closer to the hand than 50 cm from the distal end of the scope is the hardest state portion H. Then, the distal end of the coil pipe 32 inserted into the inside of the flexible tube 12B is connected to the hardest part twisted distal end side of the flexible tube base end side, and a hardness change area 34b of approximately 30 cm from the distal end of the scope. It is disposed on the soft flexible portion closer to the distal end portion 10.

The solid line in the graph of FIG. 6 shows the hardness of the flexible tube 12 in a soft state in which the hardness adjustment wire 33 inserted through the coil pipe 32 is not pulled, and the broken line in the graph indicates that the hardness adjustment wire 33 is maximized. It shows the hardness of the flexible tube 12 in the hard state where the coil pipe 32 is compressed most by being pulled. In this endoscope, the hardness on the distal end side can be changed from a hardness change area 34b provided near 50 cm from 34 cm from the end surface of the endoscope. The hardness change region 34b is formed by gradually increasing the mixing ratio of a hard resin material in the middle of a soft resin material. Other configurations are the same as those of the flexible tube 12A shown in FIG. 5, and the same members are denoted by the same reference numerals and description thereof will be omitted.

The operation of the endoscope 1 configured as described above will be described with reference to FIG.
First, the insertion section 2 of the endoscope 1 is inserted into the meandering sigmoid colon 53 from the anus 51 through the rectum 52 as shown in FIG. At this time, the flexible tube 12A is in a soft state. For this reason, the hardness in the range of about 50 cm from the distal end of the scope is soft, so that the sigmoid colon 53 is inserted without causing any pain while forming a loop corresponding to the bent shape.

In addition, depending on the insertion method of the operator, the hardness adjusting wire 33 is operated to gradually compress the coil pipe 32 to linearize the flexible tube 12A without forming a loop in the sigmoid colon 53. An insertion method of insertion (while shortening the sigmoid colon 53 so as to fold) may be used. In this case, by compressing the coil pipe 32 and setting the hardness of the flexible tube 12A to the desired hardness of the operator, a delicate hand operation such as pushing and pulling or twisting at hand is transmitted to the tip. It is inserted smoothly.

Next, when the distal end portion 10 of the endoscope 1 reaches the vicinity of the descending colon 54 or the spleen bend 55 over the sigmoid colon 53, the flexible tube 12A is twisted as shown in FIG. The loop is released by pulling while pulling, and this time, the state is made as close to a straight line as possible. At this time, the sigmoid colon 53 is in a folded state. Further, when the flexible tube 12A is in a soft state, the hardness of the distal end portion 10 is changed to a desired hardness by appropriately operating the hardness adjusting wire 33, so that the distal end portion 10 can move the transverse colon 56, the liver curve 57, the ascending colon 58, At the time of insertion into the cecum 59, the hand operation is transmitted to the distal end portion 10 sensitively and smoothly inserted.

In addition, the shape of the transverse colon 56 and the liver curve 57 may be different depending on the patient. For example, in the case of a patient whose shape of the transverse colon 56 and the liver curve 57 is not so complicated, the hand operation is performed to fold the transverse colon 56. Then, it is possible to make the distal end portion 10 reach the cecum 59 in a substantially straight line as shown in FIG. . As described above, in the case of a patient whose shape of the transverse colon 56 and the liver curve 57 is not so complicated, the distal end portion 10 can be quickly inserted into the cecum by adjusting the flexible tube 12A to a desired hardness. .

On the other hand, in the case of a patient whose transverse colon 56 is very long or has a complicated shape, it is difficult to fold the transverse colon 56 by performing a manual operation, which may not be performed well. In such a case, the user inserts the transverse colon 56 by pushing it while forming a loop by hand, and slides the distal end portion 10 along the intestinal wall. In this insertion method, when the flexible tube 12A is in a hard state, the flexible tube 12A cannot cope with the bent shape of the transverse colon 56 or the liver curve 57, and the insertability may be deteriorated. The flexible tube 12A is made to be in a soft state, and the soft flexible portion on the distal end side is pushed along the shape of the transverse colon 56 and the liver curve 57 and inserted as shown in FIG.

In addition, when the operator performs insertion of the endoscope into the large intestine alone, when the operator passes through a bent portion of the large intestine, the operator generally passes through a curved portion in the UP direction. That is, the bending direction in the DOWN, LEFT, and RIGHT directions is not often used, and the insertion direction is determined by the bending operation in the UP direction and the hand operation of the twisting operation of the flexible tube 12. Therefore, the flexible tube 12 also passes through each bent portion of the large intestine while bending in the UP direction.

Also, as shown in the graphs of FIGS. 5 and 6, by setting the hardness on the proximal side from the part 50 cm from the distal end of the scope to be harder than the distal end surface side even in the soft state, FIG. As shown in (), the sigmoid colon 53, which has been shortened once, forms a loop again, so that the operation at hand is hardly transmitted to the distal end portion 10.

Further, the followability can be improved by setting the position of the distal end of the coil pipe 32 near the distal end of the scope of the flexible tube 12, but the insertion method shown in FIG. Also in the case of insertion, it is conceivable to insert while inserting the insertion portion along the bending of the transverse colon 56 or the liver curve 57. For this reason, the distal end of the coil pipe 32 is arranged in the softest state portion S 30 cm from the distal end of the scope so that the loop can be formed and inserted while pushing along the bend. Then, the softest part S is left in a portion up to 30 cm from the distal end of the scope.

硬度 By arranging the distal end of the coil pipe at the softest part provided on the flexible tube, the hardness of at least a part of the softest part can be changed and adjusted. As a result, the followability of the insertion portion of the endoscope is greatly improved, and it becomes possible to cope with various insertion methods by the operator. Also, in the case where the coil pipe is inserted as shown in FIG. 7 (c), for example, since the tip of the coil pipe is located at a position closer to the hand than the part 50 cm from the tip of the scope, the distance from the tip of the scope to 50 cm is increased. The inconvenience that the hand operation that has occurred because the hardness of the softest state portion S cannot be changed and is not transmitted to the distal end portion is solved.

Further, by providing the coil pipe along the longitudinal direction of the inner wall side of the helical tube constituting the flexible tube on the UP side region or the DOWN side region, it is possible to reduce the amount of pulling force or the moving distance of the less hardness adjusting wire. Thus, a desired bending hardness can be obtained. That is, in addition to the hardness variable function originally provided by the coil pipe alone, by providing the coil pipe along the inner wall side, the bending rigidity of the flexible tube in the UP and DOWN directions is increased, and the hardness of the flexible tube is reduced. Can be set stiffer without having to apply much. As a result, it is not necessary to increase the hardness adjustment width of the coil pipe alone, and the load applied to the coil pipe and the hardness adjustment wire is reduced, so that the durability of the coil pipe and the hardness adjustment wire is improved.

Further, by disposing the distal end of the coil pipe at a position closer to the distal end than the hardness-changed portion or the hardness-changed region, a flexible tube generated by a sudden change in hardness in the hardness-changed portion or the hardness-changed region. A sharp bend can be prevented. As a result, the flexible tube has a smoothly bent shape and is inserted into the body cavity.

The hardness varying means and the operating means are not limited to coils and wires, but may be those using a shape memory alloy or an elongated balloon.

8 and 9 relate to a second embodiment of the present invention, and FIG. 8 is a diagram showing a relationship between a distance from a distal end of a scope of an endoscope provided with a flexible tube having a plurality of hardness change regions and hardness. FIG. 9 is a diagram showing the relationship between the distance from the end of the scope of the endoscope having the flexible tube in which the distance of the hardness change region is set long and the hardness.

In this embodiment, the length of the flexible tube in the longitudinal direction from the softest state portion S to the hardest state portion H is set long to prevent the flexible tube from being sharply bent in the vicinity of the hardness change region. FIG. 8 shows that during the transition from the softest state part S to the hardest state part H, the state changes to the intermediate hardness state part M which is a hardness state substantially intermediate between the softest state part S and the hardest state part H. The outer skin 31d is provided with a first hardness change region 61 to be changed and a second hardness change region 62 to change from the intermediate hardness state portion M to the hardest state portion H, and the hardness of the flexible tube 12C is stepped. It is made to change. A coil pipe 32 is inserted through the inside of the flexible tube 12C, and the distal end of the coil pipe 32 is positioned 40 cm from the distal end of the scope at the distal end from the hardest portion on the flexible tube base end side. Are arranged in the intermediate hardness state portion M so that the hardness of the intermediate hardness state portion M can be changed.

On the other hand, FIG. 9 shows an outer skin 31e having a wide hardness change region 63 in which the longitudinal distance from the softest state portion S to the hardest state portion H is set to be as long as about 45 cm. The hardness is changed steplessly. A coil pipe 32 is inserted through the inside of the flexible tube 12D. The distal end of the coil pipe 32 is positioned 30 cm from the distal end of the scope at the distal end from the hardest portion on the proximal end side of the flexible tube. Is arranged in the middle of the wide hardness change region 63 so that the hardness of the distal end side of the wide hardness change region 63 can be changed.

Note that the hardness can be changed stepwise even if the flexible tube 12C is configured by arranging three separate outer skins having different hardnesses in order from the softest one from the tip end side. The flexible tube 12C shown in FIG. 8 and the flexible tube 12D shown in FIG. 9 are slightly different in the position of the distal end of the coil pipe 32. FIG. 3 shows an example corresponding to each operator's preference.

As described above, by setting a plurality of hardness change regions or a wide hardness change region in the flexible tube, by setting a long distance in the longitudinal direction until the flexible tube changes from the softest state portion to the hardest state portion, When the flexible tube enters a loop state, a smoother bent shape can be formed. As a result, when the endoscope is inserted, better insertability can be obtained.

FIG. 10 is a diagram showing a relationship between a distance from a distal end of a scope of an endoscope provided with a flexible tube having a hardness change portion and a hardness change region according to a modification of the second embodiment of the present invention and hardness.
As shown in the figure, the flexible tube 12E of the present embodiment is provided with a hardness change portion 64 and a hardness change region 65 to change the hardness stepwise.

The hardness changing portion 64 is provided by disposing the coil pipe 32a inside the flexible tube 12E. That is, the coil pipe 32a itself has a larger wire cross-sectional area than the above-described coil pipe 32, for example, and has a higher hardness set in advance. For this reason, the transition from the softest state portion S on the distal end side of the flexible tube 12E to the intermediate hardness state portion M is performed not by changing the hardness of the outer cover 31 constituting the flexible tube 12 but by changing the hardness. The hardness is changed by a built-in member disposed in the flexible tube 12.

Thus, by changing the hardness of the flexible tube by the built-in member inserted through the inside of the flexible tube, a plurality of hardness changing portions having different hardnesses can be easily provided. As a result, the hardness of the flexible tube can be changed stepwise without preparing a plurality of separate outer skins having different hardnesses, so that the number of outer skins can be reduced and the manufacturing process can be simplified.

As shown in FIG. 8, when two hardness change areas are provided on the outer skin during molding, the hardness increases stepwise as the difference in hardness between the softest state part and the hardest state part increases. Since it becomes difficult to change the hardness, as shown in FIG. 10, by changing either one of the hardness change regions by providing the built-in component, a stepwise change in the hardness can be easily realized. The built-in member for changing the hardness of the flexible tube is not limited to the coil pipe, but may be a built-in member such as an air supply tube or a water supply tube, and changes the thickness of these tubes. It can also be done by

FIG. 11 shows the relationship between the distance from the distal end of the scope and the hardness of an endoscope including a flexible tube having two hardness change regions according to the first embodiment and a modification of the second embodiment of the present invention. FIG.
As shown in the figure, in the present embodiment, a front side hardness change area 66 and a rear side hardness change area 67 are provided in the flexible tube 12F. The front side hardness change region 66 changes the softest state portion S from the hardest state portion S to the hardest state portion H, whereas the rear side hardness change region 67 changes the hardest state portion H to a soft hand soft portion 68. Is changed.

As described above, by providing the soft part at the hand side by the rear side hardness change area that softly changes the hardest state part at the hand side of the flexible tube, the operation part is twisted as much as possible when inserted into the sigmoid colon in the soft state. When the flexible tube is twisted without being used, the soft hand soft portion bends to absorb the twist of the flexible tube, and the amount of twisting force can be reduced. This improves the operability of twisting the flexible tube.

When inserted deep into the large intestine, there is a possibility that the soft hand portion 68 may be bent by being inserted up to the hand soft portion 68 located closer to the hand than the hardest state portion H. However, since the coil pipe 32 is inserted through the soft hand portion 68, the rigidity of the coil pipe 32 is increased to compensate for the softness of the soft hand portion 68, and the soft hand portion 68 may be bent in a living body. Is prevented.

Note that the present invention is not limited to only the above-described embodiments, and various modifications can be made without departing from the spirit of the invention.

[Appendix]
According to the above-described embodiment of the present invention as described in detail above, the following configuration can be obtained.

(1) A flexible tube having flexibility that is formed so that the hardness at the base end side is higher than the distal end side in the longitudinal direction of the insertion portion, and the flexibility provided along the longitudinal axis inside the flexible tube. In an endoscope having a hardness variable means for changing the hardness and an operating means for adjusting the hardness of the hardness variable means to change the flexible tube to an arbitrary hardness,
An endoscope in which the distal end of the variable hardness means is disposed distally from the hardest part on the base end side of the flexible tube, and at least a part of the distal end of the flexible tube is variable in hardness.

(2) The flexible tube is composed of a soft flexible portion on the distal end side and a hard flexible portion on the hand side, and the distal end of the hardness varying means is located at a position more distal than the hardest portion on the proximal end side of the flexible tube. An endoscope which is disposed on a soft flexible portion of a flexible tube on the side, and at least a part of the soft flexible portion has a variable hardness.

(3) An endoscope in which a hardness changing portion in which the hardness of the flexible tube is switched and a position where the hardness is changed by the hardness changing means are different.

(4) An endoscope wherein the hardness varying means is provided along the longitudinal direction on the inner wall side of the flexible tube in the UP direction or the DOWN direction in the vertical section of the flexible tube.

1 to 7 relate to a first embodiment of the present invention, and FIG. 1 is an explanatory diagram showing a schematic configuration of an electronic endoscope. AA sectional view of FIG. Schematic view for explaining the arrangement position of the coil pipe in the flexible tube BB sectional view of FIG. The figure which shows the relationship between the distance from the scope front-end | tip of the endoscope provided with the flexible tube which has a hardness change part, and hardness. The figure which shows the relationship between the distance from the scope front-end | tip of the endoscope provided with the flexible tube which has a hardness change area, and hardness. The figure which shows the insertion state at the time of inserting the endoscope transanally. FIGS. 8 and 9 relate to a second embodiment of the present invention, and FIG. 8 is a diagram showing the relationship between the distance from the distal end of a scope of an endoscope provided with a flexible tube having a plurality of hardness change areas and the hardness. The figure which shows the relationship between the distance from the scope front-end | tip of the endoscope provided with the flexible tube which set the distance of the hardness change area long, and hardness. The figure which shows the relationship between the distance from the scope front-end | tip of the endoscope provided with the flexible tube which has the hardness change part and hardness change area | region which concerns on the modification of 2nd Embodiment of this invention, and hardness. The figure which shows the relationship between the distance from the scope front-end | tip of the endoscope provided with the flexible tube which has two hardness change areas based on the said 1st Embodiment of this invention and the modification of 2nd Embodiment, and hardness.

Explanation of reference numerals

10: Tip 12A: Flexible tube
32 ... Coil pipe
Attorney Susumu Ito

Claims (1)

Hardness changing means for changing the flexibility of the flexible tube provided along the longitudinal axis inside a flexible tube connected to the curved portion constituting the insertion portion, and adjusting the hardness of the hardness changing means. Operating means for changing the hardness of the flexible tube, the endoscope capable of bending the distal end of the insertion portion in a predetermined direction,
In a configuration in which the end of the insertion section is bent by the bending operation so as to be directed upward or downward on the monitor screen as the vertical direction of the endoscope,
An endoscope, wherein the hardness varying means is provided on an upper inner wall side or a lower inner wall side in a vertical cross section of the flexible tube.

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