JP2010240217A - Endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To adjust the curvature direction of a curvature part and the lead-out direction of an observation visual field and treatment member of a tip rigid part without particularly enlarging the diameter of an insert part, and maintain perfection of internal gas tightness of the insert part. <P>SOLUTION: The curvature part 3b and the tip rigid part 3c of the insert part 3 are detachably connected to each other. Engagement projections 38 on a tip ring 32 of the curvature part 3b, and lock holes at a base end part of a tip part body 30 of the tip rigid part 3c are respectively formed in the circumferential direction at a prescribed pitch interval. The tip rigid part 3c is connected as it is rotated to the curvature part 3b to stop its rotation. An outer skin layer 34 is extended to an outer circumferential surface of the tip part body 30 to be fixed by a tip fixing part 35. A seal wall 36 is provided on the tip ring 32, and on the tip side over the seal wall 36, a buffer space 37 is formed to house an insert member with sufficient length. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an endoscope capable of adjusting the direction of an observation visual field.

  The endoscope is provided with an insertion part connected to the main body operation part, and the insertion part is provided with a soft part connected to the main body operation part, and a bending part and a hard tip part constituting the tip part of the soft part. It consists of parts. The distal end hard part is provided with an endoscope observation means including an illumination part and an observation part, and is provided with a treatment instrument insertion passage through which forceps and other treatment instruments are inserted. The direction of the observation visual field by the endoscope observation means and the direction in which the treatment instrument is led out in the treatment instrument insertion path are the same direction, but as the direction, a direct-viewing endoscope directed in the extension direction of the axis of the insertion portion, There is a side-view endoscope that has a field-of-view range that is substantially perpendicular to the axis of the insertion portion.

  In the case of a side-view endoscope, a flat surface portion is formed on the side surface of the distal end hard portion of the insertion portion, and an illumination window and an observation window are provided on the flat surface portion. In addition, a treatment instrument outlet for deriving the treatment instrument is also formed in the flat surface portion. The exit end of the light guide faces the illumination window provided on the side surface of the hard tip portion, and solid-state imaging means is attached to the observation window. The light guide is flexible in the bending direction, and the signal cable drawn from the solid-state image pickup means is also flexible in the bending direction. Therefore, they are bent approximately 90 degrees in the hard tip portion and extend from the insertion portion to the main body operation portion.

  The side endoscope configured as described above is preferably used as a duodenoscope, the insertion portion is inserted into the duodenum, and the distal end hard portion is advanced to a position facing the nipple. In this state, the state of the nipple can be observed or inspected by the endoscope observation means including the illumination window and the observation window provided on the side surface of the hard tip portion. In addition, if necessary, a treatment instrument such as a bile duct cannulation tube or a metal stent is inserted into the treatment instrument insertion passage, and is led out from the treatment instrument outlet formed on the side surface of the distal end hard portion, and then the common bile duct from the nipple Appropriate treatment is performed by inserting into the inside.

  In the insertion portion, a bending portion is connected to the distal end hard portion. The bending portion can be bent by a remote operation by a bending operation means provided in the main body operation portion, thereby adjusting the direction of the distal end hard portion. Here, the bending portion can be bent in two or four directions, preferably in four directions, but is provided with an endoscope observation means when viewed from the main body operation portion side where the insertion portion is led out, and a treatment instrument. In general, the flat surface portion on the side surface where the outlet port is opened is upward (up direction) in the bending direction of the bending portion.

  The up direction at the time of the bending operation is the direction in which the fingertip of the hand is directed when the operator or the like grips the main body operation unit, and the main body operation unit is provided with an air supply / water supply button, a suction button, etc. Yes. In addition, when the direction opposite to the up direction is the down direction and the structure can be bent in four directions, the directions orthogonal to the up and down directions are the right and left directions. When the bending operation means is bent in the up direction, the observation field of view is bent in the upward direction.

  It is desirable that the endoscope observation means in the distal end hard portion is displaced so as to be directed toward the nipple during the bending operation in the upward direction of the bending portion. Generally, when operating an endoscope, the subject is in a lying or prone position. When the surgeon grasps the main body operation part and performs the operation, the direction of the observation visual field and the direction of the treatment instrument can be adjusted depending on the manner of grasping, the posture of the surgeon and the subject, etc. May be desirable.

  In consideration of the above points, Patent Document 1 discloses a configuration that can be adjusted in the direction of rotation about the axis between the bending portion and the distal end hard portion constituting the insertion portion. In Patent Document 1, a ring-shaped connecting portion is provided at the distal end of the bending portion, and the distal end hard portion is rotatably attached to the connecting portion. The hard end portion is provided with two operation wires for rotating operation. When one operation wire is pulled, the hard end portion rotates in one direction, and the other operation wire is When pulled, the distal end hard portion rotates in the opposite direction.

JP 2003-204926 A

  By the way, the endoscope needs to be cleaned and disinfected every time it is used, and may be heated for sterilization. In addition, it is necessary to keep the airtight so that cleaning liquid, gas, and the like do not enter the inside of the insertion portion during cleaning / disinfection. In Patent Document 1, a seal member made of an O-ring is interposed between the hard tip portion and the connecting portion on the curved portion side, but it is difficult to achieve a complete seal with this seal member. If a complete sealing mechanism is provided, the smoothness of the turning operation of the distal end hard portion by the operation wire is impaired, and there is a problem that the operation load increases. In particular, when heat treatment is performed for sterilization, the seal member is deteriorated, so that there is a problem in durability of the airtight mechanism.

  In addition, the endoscope has a very high demand for reducing the diameter of the insertion portion. As described above, two operation wires are provided, and these two operation wires are provided inside the bending portion. It is desirable from the viewpoint of not only that the structure of the rotation mechanism of the distal end hard part is complicated, but also that the filling rate inside the insertion part is high and the diameter of the insertion part is reduced. It is not a thing.

  The present invention has been made in view of the above points, and the object of the present invention is to observe the bending direction of the bending portion and the observation visual field or treatment tool of the distal end hard portion without particularly increasing the diameter of the insertion portion. The lead-out direction of the insertion portion can be adjusted, and the internal hermetic integrity of the insertion portion can be maintained.

  In order to achieve the above-described object, the present invention is provided with an insertion portion connected to the main body operation portion, and the insertion portion includes a distal end hard portion and a bending portion provided connected to the distal end hard portion. An endoscope having a configuration in which the bending portion can be bent by remote operation from the main body operation portion, and a seal wall is provided at a distal end side portion of the bending portion, and the distal end hard portion A plurality of insertion members to be connected extend from the curved portion side so as to penetrate the seal wall, and the base end portion of the distal end hard portion and the distal end portion of the curved portion can be attached and detached by a coupling mechanism. This connecting mechanism is characterized in that the distal end hard portion can be adjusted in the rotational direction with respect to the bending portion.

  The insertion part is usually composed of a soft part, a bending part, and a hard tip part in order from the side connected to the main body operation part, and the soft part bends in any direction along the insertion path. Is provided with an endoscope observation means, and the bending portion is a portion that is bent by remote operation from the main body operation portion side. The viewing direction of the endoscope and the direction of derivation of the treatment tool include a direct-viewing endoscope in front of the insertion portion and a side endoscope provided in a direction orthogonal to the axis of the insertion portion. In the case of a side endoscope, the relationship between the direction of the bending operation, the direction of the observation field of view, and the direction of the treatment instrument is extremely important. It is convenient from the viewpoint of etc. Further, even in the case of a direct-view endoscope, at least one of the direction of the observation visual field and the direction of derivation of the treatment tool does not exist on the central axis of the insertion portion. In some cases, it may be desirable to adjust the position in the rotational direction between the hard tip portion and the curved portion.

  In the case of a side endoscope, the bending portion can be bent in four directions, up and down, and left and right. One of these bending directions, for example, the up direction, the direction of the visual field observed by the endoscope observation means, and the treatment instrument outlet The direction in which the treatment tool is led out (hereinafter simply referred to as the observation direction) is matched, but the bending direction of the bending portion and the observation direction are not fixed, and the position of the rotation direction can be adjusted. It may be convenient for the surgeon to operate. For this reason, the distal end hard portion and the curved portion are connected so as to be relatively rotatable, but the adjustable angle range does not need to be so large. For example, if adjustment is possible by an angle of about 10 to 20 degrees to the left and right with respect to the center line in the up direction, the direction can be adjusted to the extent necessary for practical use.

  A light guide, a cable, a treatment instrument insertion tube, an air / water tube, and the like pass between the distal end hard portion and the curved portion. However, the tip of the operation wire for bending the bending portion is fixed in the bending portion and does not penetrate the seal wall. Therefore, when the distal end hard portion and the bending portion are assembled, a space is provided between the distal end hard portion and the sealing wall on the bending portion side, and the extra length of each insertion member described above is provided in this space. Therefore, by limiting the adjustable range of the direction of the distal end hard portion, when the distal end hard portion is separated from the curved portion, each insertion member is pulled and rotated when it is rotated. And torsional stress is minimized. In short, this space can be made to function as a buffer space that allows the insertion member to be twisted. Here, the sealing wall may be composed of a hard member, but it can be composed of a member having elasticity such as rubber or a sealing material, and in particular, a material having good heat resistance and pressure resistance, and chemical resistance. It is desirable to use

  As for the configuration of the connecting portion between the hard tip portion and the curved portion, the curved portion side is a ring-shaped member, but the hard tip portion side can be configured from a block-like member, and the block-like tip There is also a configuration in which a connection ring is provided on the main body. When the connecting portion on the distal end hard portion side is in a block shape, the distal end of the bending portion is fitted into the distal end portion main body. When both members are configured in a ring shape, they may be fitted with either one of the distal end hard portion and the curved portion facing outward.

  In order to make it easy to adjust the rotation direction of the tip hard part, it is easy to attach and detach the tip hard part to the curved part. And relative rotation must be prevented. For this purpose, a structure is provided that includes a fixing mechanism that fixes the distal end hard portion and the curved portion in a state of being prevented from rotating.

  As the anti-rotation mechanism, both members can be provided with uneven portions, and these uneven portions can be engaged with each other. When the concave and convex portion is formed in the axial direction, it is serrated or square, but a spline groove may be formed on the fitting surface. The anti-rotation mechanism provided in the axial direction does not exhibit a function of fixing in a connected state between the distal end hard portion and the bending portion. Further, the uneven portion may be formed in the radial direction, and in this case, it is desirable to form a shallow uneven shape and to be engaged by a snap action action. As a result, the detent mechanism also functions as a fixing mechanism.

  Even if a fixing mechanism is provided, it must be detachable between the distal end hard portion and the bending portion. The curved portion is provided with an outer skin layer of an elastic member made of rubber or the like, and fixes the front end of the outer skin layer, and this fixing is generally performed by a spool or an adhesive. Therefore, a fixing mechanism can be obtained by extending the outer skin layer to the distal end hard portion and fixing the end portion of the outer skin layer by winding or bonding. Moreover, it is good also as a structure which fixes between them using screwing etc.

  The bending portion and the distal end hard portion of the insertion portion can be stably fixed with the position adjusted in the rotational direction, and the insertion portion does not have a large diameter for this position adjustment. The internal airtightness of the can be kept.

FIG. 3 is an explanatory diagram illustrating a configuration of a side endoscope. It is an external view of the front-end | tip part in the insertion part of the endoscope of FIG. It is a longitudinal cross-sectional view of FIG. It is XX sectional drawing of FIG. It is a front view of the insertion part which shows the bending direction of a bending part, and the direction of a front-end | tip hard part, Comprising: It is a figure which shows the state which made the observation visual field and the bending direction correspond. It is a front view of the insertion part which shows the bending direction of a bending part, and the direction of a front-end | tip hard part, Comprising: It is a figure which shows the state which changed the observation visual field and the bending direction into the rotation direction. It is a top view of the front-end | tip part of the insertion part which shows the state which isolate | separated the bending part and the front-end | tip hard part. It is sectional drawing in the YY position of FIG. 3 which shows the structure of the rotation prevention mechanism in the state which connected the bending part and the front-end | tip hard part. It is a principal part top view which shows the other structural example of the rotation prevention mechanism in the state which connected the bending part and the front-end | tip hard part. It is a principal part top view which shows the structure which shows another example of a structure of the rotation prevention mechanism in the state which connected the bending part and the front-end | tip hard part.

    Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a side-view endoscope will be described as an endoscope, but a direct-view endoscope can be configured similarly. In FIG. 1, reference numeral 1 denotes an endoscope. The endoscope 1 is provided by connecting an insertion portion 3 to a main body operation portion 2, and a universal cord 4 is drawn from the main body operation portion 2. The insertion portion 3 is a flexible portion 3a that is bent in an arbitrary direction along the insertion path from the connecting portion with the main body operation portion 2, and a bending portion 3b is connected to the tip of the flexible portion 3a. Further, a distal end hard portion 3c is provided at the distal end of the bending portion 3b. The main body operation unit 2 is provided with operation knobs 5a and 5b as bending operation means. By operating the operation knobs 5a and 5b, the bending unit 3b is bent vertically and horizontally.

  FIG. 2 shows the appearance of the distal end portion of the insertion portion 3 of the endoscope 1. A flat surface portion 10 is formed on a side surface portion of the distal end hard portion 3c provided continuously with the bending portion 3b, and an illuminating portion 11 and an observation portion 12 are provided on the flat surface portion 10 as endoscope observation means. This is configured as a side-view endoscope in which the direction of the observation visual field is directed in a direction orthogonal to the axis of the insertion portion 3. The illumination unit 11 is equipped with an illumination lens facing the light guide exit end. The observation unit 12 is provided with an objective optical system, and a solid-state imaging unit faces the image forming position of the objective optical system. In addition, since the specific structure of the illumination part 11 and the observation part 12 is known, illustration and detailed description are abbreviate | omitted.

  Here, as a side endoscope, the endoscope 1 is mainly used as a duodenoscope, inserted through the subject's oral cavity, and inserted from the esophagus through the stomach to the duodenum. A nipple leading to the biliary tract is opened in the cavity wall of the duodenum. Then, a treatment instrument such as a cannulation tube or a stent is inserted into the biliary tract through the nipple and from the biliary tract into the common bile duct or the like, and a predetermined examination or treatment is performed. For this purpose, the endoscope 1 is provided with an insertion path for inserting the treatment tool.

  As shown in FIG. 1, a treatment instrument introduction section 6 is provided in the main body operation section 2 at the entrance of the treatment instrument insertion path. Also, in FIG. 3, reference numeral 13 shown at the distal end hard portion 3 c in the insertion portion 3 is a treatment instrument insertion passage made of a flexible tube, and this treatment instrument insertion passage 13 is a treatment instrument introduction in the main body operation portion 2. The treatment instrument insertion passage 13 communicates with the portion 6 and is directed in the axial direction in the insertion portion 3 and is connected to a recess formed in the distal end hard portion 3c. This recessed portion is a treatment instrument standing space 14, and this treatment instrument standing space 14 is opened as a treatment instrument outlet 14a at a portion of the flat surface portion 10. The treatment instrument standing space 14 is a space for changing the direction of the treatment instrument guided in the axial direction of the insertion portion 3 by the treatment instrument insertion passage 13 toward the direction of deriving from the treatment instrument outlet 14a. A treatment instrument stand 15 is mounted in the instrument stand space 14. As a result, the treatment instrument extended in the axial direction of the insertion portion 3 changes its direction by a predetermined angle including the direction orthogonal to the axial line of the insertion portion 3 and is led out from the treatment instrument outlet 14a.

  The treatment instrument stand 15 is provided to control the angle of the treatment instrument guided from the treatment instrument insertion path 13 to the treatment instrument standing space 14 when the treatment instrument is led out from the treatment instrument outlet 14a. Accordingly, the treatment instrument standing space 14 is elongated in the axial direction of the insertion portion 2, and the treatment instrument outlet 14a is greatly opened. The treatment instrument stand 15 has a treatment instrument guide surface 15a for the treatment instrument, and appropriately performs a raising / lowering operation by remote operation from the main body operation unit 2 side. In FIG. 3, the position indicated by the solid line is the minimum angle position where the treatment instrument stand 15 is most inclined, and the position indicated by the alternate long and short dash line is the maximum angle position where the treatment instrument stand 15 is most upright. The range between the minimum angle position and the maximum angle position is the operation range of the operation of raising and lowering the treatment instrument stand 15 and guides the treatment instrument of the treatment instrument guided along the treatment instrument guide surface 15a of the treatment instrument stand 15. The direction of derivation from the outlet 14a is controlled.

  As shown in FIG. 4, the treatment instrument stand 15 is rotatably supported on the side partition wall 14 b of the treatment instrument standing space 14 of the distal end rigid portion 3 by a rotation shaft 16. The rotating shaft 16 passes through the side partition wall 14 b and extends into the lever housing space 17 defined by the side partition wall 14 b, and is connected to the driven lever 18 in the lever housing space 17. ing. When the driven lever 18 is rotated in the front-rear direction, the treatment instrument stand 15 is rotated around the axis of the rotation shaft 16 to perform the raising / lowering operation. For this purpose, the driven lever 18 is connected to a standing operation wire 19a constituting a control cable 19 (see FIG. 8), and the rotating shaft 16 is rotated by pushing and pulling the standing operation wire 19a. Thus, the treatment instrument stand 15 moves up and down. The raising / lowering operation of the treatment instrument stand 15 is performed on the main body operation unit 2 side. For this purpose, the main body operation unit 2 is provided with an upright operation lever 7.

  When the endoscope 1 is configured as a duodenoscope, the distal end hard portion 3c of the insertion portion 3 is inserted to the position of the nipple in the duodenum. For example, when a cannulation tube is inserted into the bile duct as a treatment instrument, the cannulation tube is inserted into the treatment instrument insertion passage 13 from the treatment instrument introduction unit 6 provided in the main body operation unit 2. The cannulation tube is guided into the treatment instrument standing space 14 from the treatment instrument insertion passage 13, slides along the treatment instrument guide surface 15a of the treatment instrument stand 15, and is led out from the treatment instrument outlet 14a. When the treatment instrument stand 15 is raised from this state, it is bent toward the proximal end side from the treatment instrument outlet 14a and can be directed to the nipple.

  In performing the above-mentioned treatment, the observation visual field by the endoscope 1 completely puts the nipple to be observed within the visual field range. Moreover, the treatment tool led out from the treatment tool insertion passage 13 via the treatment tool outlet 14a is also directed in a predetermined direction with respect to the nipple. When the insertion portion 3 of the endoscope 1 used as a duodenoscope is inserted into the body cavity of the subject, the subject is generally in a lying position. Then, an operator who operates the endoscope 1 holds the main body operation unit 2 with one hand, performs an operation of inserting the insertion unit 3, and the distal end term hard portion 3c advances into the duodenum and faces the nipple. After the subject is placed in the prone position, the bending portion 3b is bent to adjust the direction of the distal end hard portion 3c.

  Here, when the operation knobs 5a and 5b are operated, the bending portion 3b is bent, but the direction of the distal end hard portion 3c is changed according to the operation direction of the operation knobs 5a and 5b. When either the operation knob 5a or the operation knob 5b is operated in one direction, the distal end hard portion 3c is directed in either the vertical or horizontal direction. Further, in order to turn in the oblique direction, the two operation knobs 5a and 5b are operated simultaneously. The direction of the bending operation of the bending portion 3b and the direction in which the distal end hard portion 3c is directed by this bending operation are as shown in FIG. That is, when the direction of the observation field by the observation unit 12 is A, the direction toward the observation field A is the up direction (UP), the opposite direction is the down direction (DOWN), and the right direction is the right direction. The right direction (RIGHT) and the left direction are the left direction (LEFT).

  When the distal end hard portion 3c faces the nipple, the operation knobs 5a and 5b are appropriately operated to bend the bending portion 3b, thereby providing the distal end hard portion 3c, specifically, the flat surface portion 10 formed on the side surface thereof. The observed unit 12 is moved closer to or away from the nipple. Further, when the treatment tool is inserted, the treatment tool is led out from the treatment tool outlet 14a, and the treatment tool stand 15 is raised and lowered so as to aim at the nipple. For this reason, when the bending portion 3b is operated in the up direction, the observation unit 12 is generally set so as to be close to the nipple, and when operated in the down direction, the observation unit 2 is set apart from the nipple.

  However, for the surgeon, it may be preferable in operation that the curved portion 3b does not match the up direction and the direction of the observation visual field due to its individuality, wrinkles, etc., or anatomical characteristics of the subject. That is, it is not always advantageous to make the direction A of the observation field coincide with the up direction during the bending operation of the bending portion 3b. As shown in FIG. 6, when the direction of the observation visual field tilted in the left or right direction with respect to the up direction in the operation direction of the bending operation is (A ± α) and the bending portion 3b is operated in the up direction. In addition, there are cases where it is desirable that the observation field of view does not change in the direction of rising straight. In addition, when it is necessary for the smooth operation by the operator that the direction of the observation visual field (A ± α) and the bending direction of the bending portion 3b can be adjusted, that is, the visual field direction can be rotated. There is.

  Therefore, the configuration is such that the direction of the observation field can be easily adjusted. Therefore, as shown in FIG. 7, the bending portion 3b and the hard tip portion 3c are configured to be separable and coupled so as to be relatively rotatable. Here, various insertion members are extended from the front-end | tip hard part 3c toward the curved part 3b. Specifically, a treatment instrument insertion path 13 comprising a light guide 20 for transmitting illumination light toward the illumination unit 11, a cable 21 connected to a solid-state imaging means provided in the observation unit 12, and a flexible tube is possible. There are a flexible tube 22 and a cleaning fluid supply tube 23 for cleaning the surface of the observation unit 12. A control cable 19 is also inserted.

  As apparent from FIG. 3, the distal end hard portion 3 c includes a distal end portion main body 30 and a distal end cover 31 made of an elastic member provided so as to cover the outer surface of the distal end portion main body 30. On the other hand, the bending portion 3b is obtained by pivoting a bending ring in the order of up and down, left and right, and the most advanced bending ring, that is, the distal end ring 32 is inserted into the base end portion of the distal end portion main body 30, and its outer periphery. The part is covered with a net 33 made of a metal wire, and further covered with a stretchable outer skin layer 34 such as rubber. Here, although the flat surface portion 10 is formed on the distal end hard portion 3c, the flat surface portion 10 does not extend over the entire length of the distal end hard portion 3c, but a portion on the proximal end side of the distal end portion main body 30 in the distal end hard portion 3c. Has a circular cross section. And it is a site | part with this circular cross section inserted by the front-end | tip ring 32. Further, the outer skin layer 34 extends from the position of the tip ring 32 to the tip side, and after winding the thread at a portion having a circular cross section in the tip portion main body 30 constituting the tip hard portion 3c, an adhesive is applied. It is set as the structure fixed using. This is the tip fixing portion 35 of the outer skin layer 34. A connection mechanism is comprised by the above structure.

  FIG. 3 shows a cross section of a portion constituting the treatment instrument lead-out path. On a different cross section, the light guide 20 extended to a position facing the illumination lens in the illuminating unit 11, observation The cable 21 connected to the solid-state imaging device provided at the image forming position of the objective optical system in the section 12, the flexible tube 22 and the supply tube 23 constituting the treatment instrument insertion path are extended from the curved portion 3b to the distal end of the distal end hard portion 3c. The main body 30 is connected. A control cable 19 is also provided. These are insertion members in the insertion portion 3, and as shown in FIG. 8, their tip portions are attached to through holes 24, 25, 26, 27, 28 formed in the tip portion main body 30. And it is hold | maintained airtight by providing a sealing material around the through-hole to which each insertion member is connected. On the other hand, the bending portion 3b and the distal end hard portion 3c can be separated, and the distal end fixing portion 35 is removed and the entire distal end hard portion 3c is separated from the bending portion 3b.

  As described above, when the distal end hard portion 3c and the bending portion 3b are separated from each other, in order to keep the portion from the inside of the insertion portion 3 to the main body operation portion 2 in an airtight state, the vicinity of the distal end of the bending portion 3b A seal wall 36 is mounted at a position, and each of the insertion members described above extends so as to penetrate the seal wall 36. The seal wall 36 is made of an elastic member such as rubber and is fixed to the inner surface of the tip ring 32. And between the outer peripheral surface of the seal wall 36 and the inner peripheral surface of the tip ring 32, and around the through hole provided for inserting various insertion members from the curved portion 3b side toward the tip hard portion 3c. By filling the sealing material, the portion of the sealing wall 36 is kept airtight.

  Here, the seal wall 36 is on the tip side of the tip ring 32 where the tip of the operation wire for bending operation is fixed, and the tip of the seal wall 36 is connected to the tip hard portion 3c. The hard part 3c is located away from the base end side surface of the distal end main body 30. Therefore, a predetermined space exists between the seal wall 36 and the proximal end surface of the distal end main body 30, and this is the buffer space 37. Each insertion member described above is in a state of having a predetermined extra length inside the buffer space 37.

  Thus, the reason why each insertion member has a surplus length inside the buffer space 37 is to enable the direction adjustment of the distal end hard portion 3c. As already described, the distal end hard portion 3c has an angle (A ± α) in which the observation visual field of the observation portion 12 is tilted to the left or right with respect to the direction A that coincides with the upward bending direction of the bending portion 3b. Can be. When the distal end hard portion 3c is separated from the curved portion 3b, each insertion member is pulled out, and when the distal end hard portion 3c is rotated, twisting of each insertion member must be allowed. Accordingly, a surplus length is provided for the length of each insertion member to allow the pull-out length and twisting. When the distal end hard portion 3 c is remounted on the curved portion 3 b, the extra length is stored in the buffer space 37. For this reason, there is a limit to the possible rotation angle of the distal end hard portion 3c, and it is desirable that the rotation angle is about 15 degrees in the left-right direction. When adjusting the distal end rigid portion 3c in the rotational direction, as shown in FIG. 7, the distal end fixing portion 35 of the outer skin layer 34 is removed and the distal end portion is pulled toward the proximal end side. Or, it is separated from the connecting portion between the distal end hard portion 3c and the bending portion 3b.

  After the distal end hard portion 3c is rotated and connected to the bending portion 3b, the angular state is maintained by preventing rotation. That is, as shown in FIG. 8, engagement protrusions 38 are formed at a predetermined pitch interval in the circumferential direction at the fitting portion of the distal end ring 32 on the proximal end surface of the distal end portion main body 30. A fastening hole 39 into which these engaging projections 38 are fitted is formed. Accordingly, the distal end hard portion 3c can be fixed in a state of being rotated at intervals of the engagement projections 38, 38, and the resolution of the rotation angle can be obtained based on the interval of the engagement projections 38. The engagement protrusion 38 is engaged with the fixing hole 39, so that the distal end hard portion 3c is prevented from coming off from the curved portion 3b. Further, a distal end fixing portion 35 is provided that is fixed to the outer peripheral surface of the distal end portion main body 30 constituting the distal end hard portion 3c at a position closer to the distal end side than the distal end ring 32 by the outer skin layer 34 of the curved portion 3b. Therefore, the distal end hard portion 3c is held in a state of being connected to the bending portion 3b.

  Here, when the bending portion 3b and the distal end hard portion 3c are connected, the distal end ring 32 gets over the engaging protrusion 38. The tip ring 32 is made of a metal material having elasticity, and the tip portion of the tip ring 32 gets over the engaging projection 38 by a snap action action. For this reason, the protruding height of the engaging projection 38 is made too small. When it is high, it becomes difficult to attach and detach. Here, not only the engagement protrusion 38 and the fastening hole 39 are engaged, but also the distal end fixing portion 35 of the outer skin layer 34 functions as a fixing mechanism. There is no risk that the portion 3c will fall off.

  Thus, by rotating the distal end hard portion 3c to the bending portion 3b and adjusting the direction, the direction of the observation visual field and the bending direction of the bending portion 3b in the up direction are most easily operated by the operator. An angle can be given. As a result, the operability of the operation of the endoscope 1 by the operator is improved, and it is not necessary for the subject to take an unreasonable posture, so that the pain of the subject can be reduced.

  As a means for fixing the rotation of the distal end hard portion 3c, not only the engagement between the engagement protrusion 38 and the fastening hole 39 described above, but also the distal end surface of the distal end ring 32 of the bending portion 3b, as shown in FIG. The concave / convex engaging portions 40, 40 can be formed between the distal end hard portion 3c of the distal end ring 32 and the abutting surface of the distal end main body 30, and as shown in FIG. It can also be set as the serrated engagement part 41 and 41 instead of a part.

DESCRIPTION OF SYMBOLS 1 Endoscope 2 Main body operation part 3 Insertion part 3a Soft part 3b Bending part 3c Hard tip part 10 Flat surface part 19 Control cable 20 Light guide 21 Cable 22 Flexible tube 22 Supply tube 30 Tip part main body 31 Tip cover 32 Tip ring 34 Outer skin layer 35 Tip fixing portion 36 Seal wall 37 Buffer space 38 Engagement protrusion 39 Fastening hole 40 Uneven engagement portion 41 Serrated engagement portion

Claims (4)

An insertion part is connected to the main body operation part, and the insertion part has a structure having a hard tip part and a bending part provided to be connected to the hard tip part, and is remotely operated from the main body operation part. In the endoscope that enables the bending portion to be bent,
A seal wall is provided at a distal end portion of the curved portion;
The plurality of insertion members connected to the distal end hard part extend so as to penetrate the seal wall from the curved part side,
The proximal end portion of the distal end hard portion and the distal end portion of the bending portion are detachably connected by a connecting mechanism, and the connecting mechanism causes the distal end hard portion to rotate with respect to the bending portion. An endoscope characterized in that the position can be adjusted. When the curved portion and the hard tip portion are connected, a buffer space is formed that allows the insertion members to be twisted between the seal wall and the end surface of the hard tip portion. The endoscope according to claim 1, characterized in that: The coupling mechanism includes a fitting portion that fits between the hard tip portion and the bending portion, and a fixing means that prevents separation of the fitting portion and prevents rotation. The endoscope according to claim 1 or 2. The fixing means forms a concavo-convex portion in a radial direction or an axial direction engaging with each other at a distal end portion of the bending portion and a proximal end portion of the distal end hard portion of the fitting portion, and the bending portion The endoscope according to claim 3, wherein the outer tube is extended to a portion of the outer peripheral surface of the hard tip portion and the tip is fixed.

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