JP2009136609A - Treatment instrument insertion channel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To narrow the diameter of an insertion pathway of a treatment instrument insertion channel while keeping the circular shape of the cross sectional shape of the pathway. <P>SOLUTION: This treatment instrument insertion channel is provided with: a cylindrical connecting pipe 20 installed to a treatment instrument lead-out hole 11 provided at a rigid tip portion 2c of the insertion section 2 of an endoscope, and allowing the insertion of the treatment instrument in its inside; a flexible treatment instrument insertion tube 30 having one end fitted to the connecting pipe 20 and the other end reaching the treatment instrument introduction portion provided in a body operation section 1 connected to the insertion section 2 and allowing the insertion of the treatment instrument in its inside; wherein the connecting pipe 20 is formed with one or a plurality of opening portions 20F formed by axially cutting it off from the side for fitting the treatment instrument insertion tube 30 till at least a midway position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a treatment instrument insertion channel of an endoscope used for medical purposes and the like.

  An endoscope used for medical purposes or the like is configured by a universal cord connected to a main body operation unit with an insertion unit into a body cavity or the like, and connected to at least a light source device from the main body operation unit. The insertion portion of the endoscope is composed of a hard tip portion, a curved portion, and a soft portion from the tip side, and at least the illumination means and the observation means are provided in the hard tip portion. The illumination means is such that the exit end of a light guide (a bundle of many thin optical fibers) faces the illumination lens, and the observation means comprises an optical system such as an objective lens. In addition to these, a treatment instrument insertion channel and the like for inserting forceps and other treatment instruments are provided.

  The treatment instrument insertion channel is made of a flexible tube, and a rigid treatment instrument insertion pipe is fitted to the distal end of the treatment instrument insertion channel. A through hole for connecting the illumination means, the observation means, and the treatment instrument insertion pipe is provided in the distal end hard portion. In each through hole, an illumination lens barrel as the illumination means and an observation as the observation means are provided. The lens barrel and connecting pipe are fixed. A technique for configuring the distal end portion of the endoscope in this manner is disclosed in Patent Document 1.

In the technique of Patent Document 1, the cross-sectional shape of the channel hole provided in the distal end portion of the endoscope is a flat shape, and the cross-sectional shape of the flexible channel tube connected to the channel hole is formed in a substantially circular shape. These channel holes and channel tubes are for perfusion. By making the cross-sectional shape of the channel holes flat, the channel hole space is secured, and by making the cross-sectional area equal to that of the circular shape, The perfusion rate is increased without increasing the diameter.
JP 2006-122498 A

  By the way, the treatment instrument insertion channel serves as an insertion path for forceps and other treatment instruments, and the cross-sectional shape thereof is preferably circular. Although the treatment tool can be inserted into the channel of Patent Document 1, a special-shaped treatment tool (flat forceps cup) is inserted, and the purpose is to secure perfusion rate. If secured, there is no particular problem even if the shape of the channel hole is not circular. However, when a treatment instrument insertion channel with a channel hole with a flat cross-sectional shape is used when inserting a normal treatment instrument, the size of the treatment instrument that can be inserted is shorter than the major axis and minor axis of the flat channel hole. Depends on the diameter. If it does so, the treatment tool which can be inserted will be limited to the thing of a small size. On the other hand, if various treatment tools can be inserted with the flat channel hole, the channel hole becomes thicker. Therefore, in the case of using a general treatment instrument, it is desirable that the treatment instrument insertion channel has a circular cross section as a whole, regardless of whether the treatment instrument is used in a special shape.

  Therefore, an object of the present invention is to reduce the diameter by holding the cross-sectional shape of the insertion path of the treatment instrument insertion channel in a circular shape.

  In order to solve the above problems, the treatment instrument insertion channel according to claim 1 of the present invention is attached to a treatment instrument lead-out hole provided in the distal end hard portion of the insertion portion of the endoscope, and the treatment instrument is inserted therein. A cylindrical connecting pipe, one end of which is fitted into the connecting pipe, and the other end is connected to the treatment instrument introduction section provided in the main body operation section connected to the insertion section, and the treatment instrument can be inserted therein. A flexible treatment instrument insertion tube, and the connecting pipe is formed with one or a plurality of open portions cut in the axial direction from the side where the treatment instrument insertion tube is fitted to at least an intermediate position. It is characterized by.

  According to the treatment instrument insertion channel of the first aspect, the treatment instrument insertion tube is substantially planarized at the portion where the opening portion of the connection pipe is formed, and at least the thickness of the connection pipe can be reduced. In particular, since the portion where the treatment instrument insertion tube is fitted to the connecting pipe is thick, the diameter of the insertion portion can be reduced by making this portion thin. If the opening portion is formed larger, the diameter can be reduced accordingly. However, as the opening portion becomes larger, the cross-sectional shape of the insertion path of the treatment instrument is greatly deformed from the original circle. For this reason, it is desirable to form the open portion so as to be approximately the same as or slightly larger than the thickness of the connecting pipe. Thereby, while maintaining the cross section of the treatment instrument insertion passage in a substantially circular shape, that is, without substantially changing the inner diameter, the outer diameter of the part can be reduced, and the overall diameter can be reduced. .

  The opening portion may be formed at one place of the connecting pipe, but may be a plurality of places. When there is one open part, the open part has a C-shaped arc shape as a whole, and when there are two open parts, it becomes two divided semicircular shapes. If the open part is formed in many places, the outer diameter of the treatment instrument insertion tube at the connection part can be reduced, but the adhesion area is reduced accordingly, the adhesive strength is weakened, and the strength of the connection pipe itself is also weakened. Therefore, it is desirable to provide the opening portion at one or two locations.

  The treatment instrument insertion channel according to a second aspect of the present invention is the treatment instrument insertion channel according to the first aspect, wherein an imaging unit having a lens barrel of an objective lens and a solid-state imaging element is connected to the distal end hard portion. The open part of the connection pipe is arranged toward the imaging unit.

  According to the treatment instrument insertion channel of claim 2, the treatment instrument insertion channel and the imaging unit can be brought close to each other by directing the thinned portion by the opening formed in the connection pipe to the imaging unit, and the distal end of the insertion section The diameter can be reduced.

  The opening portion may be arranged toward the imaging unit, but may be arranged in any direction other than the imaging unit. For example, there is provided a cut-off part for fixing an operation wire for bending the bending part at the distal end of the insertion part in an arbitrary direction, but this cut-off part is located at a position where it is relatively easy to interfere with the treatment instrument insertion channel. is there. Therefore, it is possible to avoid interference between the cut-off portion and the treatment instrument insertion channel by directing the open portion toward the cut-out portion.

  A treatment instrument insertion channel according to a third aspect of the present invention is characterized in that, in the treatment instrument insertion channel according to the first aspect, an outer diameter of the connection pipe is larger than an inner diameter of the treatment instrument insertion tube.

  According to the endoscope treatment instrument insertion channel of claim 3, since the outer diameter of the connection pipe is larger than the inner diameter of the treatment instrument insertion tube, the connection pipe is connected when the treatment instrument insertion tube is fitted to the connection pipe. The part where the open part of the pipe is formed is reduced in diameter and inserted. After the insertion, the restoring force of the connection pipe and the contraction force of the treatment instrument insertion tube interact with each other, and the fixing strength of the fitting portion between the connection pipe and the treatment instrument insertion tube becomes strong. Since the contraction force acts on the entire treatment instrument insertion tube, a tension acts on the open portion, and the treatment instrument insertion tube of the cutout portion can be substantially planarized in a natural state.

  Here, when the treatment tool insertion tube is fitted to the connection pipe and assembled, the outer diameter of the connection pipe is made larger than the inner diameter of the treatment tool insertion tube, so the treatment tool insertion tube is fitted to the connection pipe. It is relatively difficult to combine. However, since the open part is formed in the connection pipe, it can be easily made thinner than the diameter of the treatment instrument insertion tube by reducing the diameter. Therefore, by temporarily reducing the outer diameter of the connection pipe, the connection pipe can be easily inserted into the treatment instrument insertion tube and can be easily fitted. That is, there is an effect that workability at the time of assembly is improved.

  A treatment instrument insertion channel according to a fourth aspect of the present invention is the treatment instrument insertion channel according to the first aspect, wherein the open portion of the connection pipe is a cut plane parallel to the tangential direction of the cylindrical shape. And

  According to the treatment instrument insertion channel of the fourth aspect, since the opening portion is a cut plane parallel to the tangential direction, the fitting portion between the connection pipe and the treatment instrument insertion tube may be smooth in the circumferential direction. it can.

  The treatment instrument insertion channel according to a fifth aspect of the present invention is the treatment instrument insertion channel according to the first aspect, wherein the connecting pipe is formed of two of an opening portion and a closing portion in which the opening portion is not formed in the axial direction. The closure portion is formed to a position closer to the base end side than the treatment instrument lead-out hole when the connecting pipe is attached to the treatment instrument lead-out hole, and the treatment instrument insertion tube is formed. When fitting to the connecting pipe, the fitting is performed from the fitting side of the treatment instrument insertion tube to the position of the closing portion.

  According to the treatment instrument insertion channel of the fifth aspect, since the treatment instrument insertion tube is fitted to the portion where the open portion is formed in the axial direction, the entire treatment instrument insertion channel can be a sealed space. it can. For this reason, even if the treatment instrument insertion channel is used as a suction passage for body fluid or the like, body fluid or the like does not leak to the outside.

  According to the present invention, since the open portion is formed in the connection pipe for connecting the treatment instrument insertion tube, the fitting portion between the connection pipe and the treatment instrument insertion tube is substantially obtained without changing the inner diameter of the connection pipe. Can be thinned. Thereby, diameter reduction can be achieved without limiting the treatment tool which can be penetrated. Moreover, since the treatment instrument insertion tube is fitted to the closed portion of the connecting pipe, body fluid or the like does not leak out.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the endoscope has a main body operation unit 1, an insertion unit 2, and a universal cord 3 and is schematically configured. The insertion portion 2 is a flexible portion 2a that bends in an arbitrary direction along the insertion path from the side connected to the main body operation portion 1, and a bending portion 2b is connected to the tip of the flexible portion 2a. Further, the distal end of the bending portion 2b is a distal end hard portion 2c. The distal end surface of the distal end hard portion 2c is provided with an endoscope observation means composed of an illuminating portion and an observation portion, and a treatment instrument outlet opening is provided for performing an operation such as suctioning of filth from the treatment instrument. Yes. The bending portion 2b is configured to allow a bending operation in order to direct the distal end hard portion 2c in a desired direction. Here, the bending direction of the bending portion 2b is set to four directions, that is, a vertical direction and a horizontal direction. Note that the bending direction may be two directions, ie, the up-down direction.

  2 to 4 show the configuration of the distal end hard portion 2c. First, in FIG. 2, the tip hard portion 2 c is mainly composed of a tip block 5, and a plurality of through holes 11, 12, 13 are formed in the tip block 5. Each through hole 11, 12, 13 is a hole penetrating from the proximal end surface of the distal end block 5 to the distal end surface. The through hole 11 is a hole for connecting a treatment instrument insertion channel 10 through which forceps, a high frequency treatment instrument and other treatment instruments are inserted, the through hole 12 is a hole for connecting an observation means, and the through hole 13 is an illumination. It is a hole for connecting means. A connecting pipe 20 made of metal or the like is fitted and fixed in the through-hole 11 (referred to as the treatment instrument outlet hole 11), and the treatment instrument insertion tube 30 made of a tube material having flexibility in the bending direction is connected to the connection pipe 20. Are fitted. The treatment instrument insertion channel 10 is composed of these members, and when the treatment instrument insertion tube 30 is fitted and fixed to the connection pipe 20, both are joined using an adhesive or the like.

  A lens barrel 41 to which a plurality of objective lens groups (shown as objective lens group 41L in FIG. 4) is attached is connected to the through hole 12. The base end side of the lens barrel 41 is connected to a prism 42 for bending the optical path by 90 degrees, and a CCD is provided on the exit surface side of the triangular prism 42 (a surface orthogonal to the surface on which light enters the prism 42). A solid-state imaging device 43 such as is connected. The solid-state image sensor 43 is mounted on a substrate 44, and a large number of signal lines 44 </ b> S for outputting electrical signals from the solid-state image sensor 43 are wired on the substrate 44. The lens barrel 41, the prism 42, the solid-state imaging device 43, and the substrate 44 constitute an imaging unit 40. The through-hole 13 is mounted with an illumination lens group that constitutes illumination means, and the exit end of the light guide 51 faces the illumination lens group. Illumination means are mounted at two locations on the distal end hard portion 2 c, and the distal end block 5 is provided with two through holes 13, and light guides 51 and 52 are connected to the respective through holes 13.

  Therefore, an illumination lens as an illumination unit and an observation lens as an observation unit are facing the distal end surface of the distal end hard portion 2c, and an image of a region to be examined is attached to the lens barrel 41 by illumination light from the illumination lens. The optical path is converted 90 degrees from the objective lens group 41L by the prism 42 so as to be incident on the solid-state image sensor 43. The incident light is photoelectrically converted by the solid-state image sensor 43 to be converted into an image signal and output to a processor device or the like. I am doing so. The distal end of the treatment instrument outlet hole 11 faces the distal end surface of the distal end block 5, and the treatment instrument is led out from the distal end hard portion 2 c via the treatment instrument insertion tube 30, the connecting pipe 20, and the treatment instrument outlet hole 11. To be able to. As the other mechanism, the distal end hard portion 2c is provided with a cleaning nozzle 60 (shown in FIG. 4) for cleaning the observation portion. The cleaning nozzle 60 is connected to an air / water supply tube (not shown).

  FIG. 3 shows a cross section of the distal end hard portion 2c. As shown in this figure, the treatment instrument insertion channel 10 including the treatment instrument insertion tube 30 and the connecting pipe 20 occupies a large space, and the imaging unit 40 also requires a relatively large space in the distal end hard portion 2c. It is said. 4 shows a cross-sectional view taken along the line AA of FIG. 3. As shown in FIG. 4, the treatment instrument insertion channel 10 and the imaging unit 40 occupy most of the distal end hard portion 2c. Then, other members such as ride guides 51 and 52 are arranged in the remaining space.

  Since the imaging unit 40 includes a plurality of members such as the solid-state imaging device 43, the substrate 44, and the lens barrel 41, the imaging unit 40 has a shape with unevenness on the left and right as a whole. As shown in FIG. 3, the lens barrel 41 has a relatively small diameter, but the substrate 44 on which the solid-state imaging device 43 is mounted is greatly pushed toward the treatment instrument insertion channel 10. That is, the arrangement mode of the imaging unit 40 and the treatment instrument insertion channel 10 must be determined in consideration of the most protruding portion of the imaging unit 40. Here, the substrate 44 is shown as projecting to the left and right, but when the other members of the imaging unit 40 are projecting most, the projecting portion and the treatment instrument insertion channel 10 are connected to each other. The arrangement mode is determined in consideration of the positional relationship.

  In the present invention, as shown in FIGS. 2 to 4, a cylindrical connecting pipe 20 is partially cut off in the axial direction to form an open portion 20F. The open portion 20F is formed by cutting a certain length (L1) from the end of the connecting pipe 20 on the side where the treatment instrument insertion tube 30 is fitted, and the remaining length in the axial direction of the connecting pipe 20 The portion (L2) is a closed portion 20C in which the open portion 20F is not formed. Since the connecting pipe 20 has a cylindrical shape, the closed portion 20C has a cylindrical shape, but the open portion 20F has a C-shaped arc shape.

  Since the connecting pipe 20 is a metal member having a spring property such as stainless steel, and the part of the opening 20F of the connecting pipe 20 is partially cut off in the axial direction, it is opened when pressure is applied to the part from the outer periphery. The connecting pipe 20 at the site where the portion 20F is formed is reduced in diameter. Therefore, the treatment instrument insertion tube 30 is fitted into the connection pipe 20 in a state where the diameter of the open portion 20F of the connection pipe 20 is reduced using a treatment instrument insertion tube 30 having a diameter smaller than that of the connection pipe 20. Let As described above, since the open portion 20F is formed by the length L1 in the axial direction from the side where the treatment instrument insertion tube 30 is inserted, the outer diameter can be inserted into the treatment instrument by narrowing the open portion 20F. The tube 30 can be inserted in a state smaller than the inner diameter. And by releasing the pressure with respect to the connection pipe 20, the connection pipe 20 and the treatment tool insertion tube 30 are fitted with a strong fixing force. Further, by applying an adhesive to the outer peripheral surface of the connection pipe 20 in advance, reducing the diameter of the connection pipe 20 and inserting it into the treatment instrument insertion tube 30, the connection pipe 20 expands, and the treatment instrument insertion tube 30. Close contact with. As described above, the assembling work becomes easy.

  After assembly, the connecting pipe 20 returns to its original diameter due to the restoring force, and the treatment instrument insertion tube 30 having a diameter smaller than that of the connecting pipe 20 is in a state in which tension is applied. Since the connecting pipe 20 has an open portion 20F, the treatment instrument insertion tube 30 in this portion is in a substantially flat state due to tension. On the other hand, the treatment instrument insertion tube 30 as a whole has a cylindrical shape with respect to the closed portion 20C. As shown in FIG. 4, the treatment instrument insertion tube 30 fitted to the connection pipe 20 has a cylindrical shape in the portion of the closing portion 20C, but is partially thin in the portion of the opening portion 20F. It becomes a thing and becomes a state of being depressed. That is, the treatment instrument insertion channel has a small diameter in the open portion 20F, and a new space is created. Accordingly, the imaging unit 40 and the treatment instrument insertion channel 10 can be brought close to each other by this space, and the overall diameter of the insertion portion 2 can be reduced.

  As shown in FIG. 3, in the axial direction, the most projecting portion of the imaging unit 40, that is, the substrate 44 and the open portion 20 </ b> F of the connecting pipe 20 are arranged adjacent to each other. In the axial direction, the lens barrel 41 having a relatively small diameter is disposed so as to be adjacent to the closing portion 20 </ b> C of the connection pipe 20. Thereby, since the part of the board | substrate 44 which the imaging unit 40 protrudes most and the open part 20F of the connection pipe 20 can be closely approached, the diameter reduction of the insertion part 2 can be achieved.

  Here, the open portion 20F is a cut plane parallel to the tangential direction of the cylindrical connecting pipe 20, and the cut plane is formed by cutting out the thickness of the connecting pipe 20 or more. However, if the cut plane of the opening 20F is formed on the inner side larger than the thickness of the connecting pipe 20, the diameter of the treatment instrument insertion channel 10 can be reduced, but the cross-sectional area is reduced. That is, the cross-sectional shape greatly changes from the original shape. Therefore, the treatment instrument insertion channel 10 can be reduced in diameter without substantially changing the inner diameter of the connection pipe 20 by forming the cut plane of the opening 20F slightly inside the thickness of the connection pipe 20. Can do. And since the plane part of a cut plane can also be utilized as an adhesion surface, adhesion strength can be secured.

  Most of the connecting pipes 20 that form the opening portion 20F are connecting pipes 20, and only the portion of the opening portion 20F has the treatment instrument insertion tube 30 substantially flat. That is, when viewed in the circumferential direction, there is no abrupt change at the change point between the connecting pipe 20 and the treatment instrument insertion tube 30. For this reason, the treatment instrument can be smoothly inserted without causing a catch or the like when the treatment instrument is inserted.

  By the way, the treatment instrument insertion channel 10 is mainly used as a passage through which the treatment instrument is inserted, and this channel is shared as a suction passage for aspirating body fluid or the like in the body cavity. In this case, a suction force is applied from the treatment instrument outlet opening provided on the distal end surface of the distal end hard portion 2 c, and body fluid or the like is sucked through the treatment instrument insertion channel 10. Since the connecting pipe 20 constituting a part of the treatment instrument insertion channel 10 has an opening 20F, if the opening 20F is exposed as it is, the opening 20F is used when used as a suction passage. A body fluid or the like leaks into the insertion portion 2 from 20F. For this reason, the treatment instrument insertion channel 10 must be sealed over the entire length.

  Therefore, in the axial direction, when the connecting pipe 20 is mounted in the treatment instrument outlet hole 11, the closing portion 20C is formed at a position closer to the base end side than the treatment instrument outlet hole 11, and the treatment instrument insertion tube 30 is When fitting to the connecting pipe 20, the fitting is performed from the fitting side of the treatment instrument insertion tube 30 to the position of the closing portion 20 </ b> C. Thereby, the part of the open part 20F is completely covered by the treatment instrument insertion tube 30. In other words, the channel diameter can be reduced without substantially changing the inner diameter of the connection pipe 20, and at the same time, the entire treatment instrument insertion channel can be sealed to prevent body fluid from leaking out.

  Next, an example in which the open portion 20F of the connecting pipe 20 is directed to the cut-off portion will be described. The uneven part formed inside the insertion part 2 is not only the imaging unit 40 but also a cut-off part formed on the curved ring of the curved part 2b, for example. That is, four operation wires are inserted to bend the bending portion 2b connected to the distal end of the flexible portion 2a of the insertion portion 2 in four directions, up and down and left and right. The four operation wires form a total of two pairs of upper and lower pairs and left and right pairs. The operation wire is inserted so that the tip is fixed to the throttle part. The cut and drawn portions are arranged at four locations on the upper, lower, left, and right inside the insertion portion 2 and protrude to some extent in the circumferential direction in order to fix the operation wire.

  FIG. 5 shows a cut-off portion to which an operation wire that is bent in the vertical direction is fixed. The cut and drawn portion 61 provided at the upper position fixes the upper operation wire 62, and the cut and drawn portion 63 provided at the lower position fixes the lower operation wire 64. The upper cut-off portion 61 is disposed at the upper position of the lens barrel 41 or the prism 42 to fix the operation wire 62. Since the lens barrel 41 and the prism 42 have a relatively large space in the upper part, it is possible to place the cut-out diaphragm 61 at this position. On the other hand, the lower cut-out portion 63 is disposed at the lower position of the connection pipe 20 and the treatment instrument insertion tube 30 to fix the operation wire 64.

  As shown in FIG. 5, since there is almost no space between the treatment instrument insertion channel 10 and the cut-out restrictor 63, it is necessary to prevent both from interfering with each other. Here, the portion where the open portion 20F of the connection pipe 20 is formed is thinned, and the open portion 20F is disposed toward the cut-off portion 63, whereby the treatment instrument insertion channel 10 and the cut-out portion 63 are interposed. It is possible to prevent interference.

  Next, another example of the imaging unit will be described. In the example shown in FIGS. 2 to 4, a prism 42 is connected to the lens barrel 41, and the light path is bent 90 degrees by the prism 42 and is incident on the solid-state imaging device 43. That is, the solid-state image sensor 43 is arranged in a direction parallel to the axial direction. FIG. 6 shows an example of another imaging unit. In the imaging unit of this example, an example in which the solid-state imaging device 65 and the substrate 66 on which the solid-state imaging device 65 is mounted is arranged in a direction orthogonal to the axial direction. In this case, since there is no need to convert the optical path, the prism becomes an unnecessary member, and the light from the lens barrel 41 is directly incident on the solid-state image sensor 65.

  As shown also in FIG. 6, when the solid-state imaging device 65 is arranged so as to be orthogonal to the axial direction, a large space in the circumferential direction is required as the entire observation means. Therefore, the diameter of the insertion portion 2 can be reduced without substantially changing the inner diameter by directing the open portion 20F of the connecting pipe 20 to the substrate 66 on which the imaging unit, particularly the solid-state imaging device 65 is mounted. Can do.

1 is an overall configuration diagram of an endoscope. FIG. It is a schematic block diagram near the front-end | tip of the insertion part of an endoscope. It is sectional drawing of the front-end | tip vicinity of the insertion part of an endoscope. It is AA sectional drawing of FIG. It is sectional drawing at the time of providing a cut-down part. It is sectional drawing at the time of arrange | positioning so that a solid-state image sensor may be orthogonal to an axial direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Insertion part 2a Soft part 2b Bending part 2c Hard tip part 5 End block 10 Treatment instrument insertion channel 20 Connection pipe 20C Closure part 20F Opening part 30 Treatment instrument insertion tube 40 Imaging unit 43 Solid-state image sensor 44 Substrate 61 Cut-down part 63 Cutting Aperture part

Claims (5)

A cylindrical connection pipe that is attached to the treatment instrument outlet hole provided in the distal end hard part of the insertion part of the endoscope and into which the treatment instrument is inserted
A flexible treatment instrument insertion tube in which one end is fitted to the connection pipe and the other end reaches a treatment instrument introduction section provided in a main body operation section coupled to the insertion section, and the treatment instrument is inserted therein; With
A treatment instrument insertion channel, wherein the connection pipe is formed with one or a plurality of open portions cut in the axial direction from the side where the treatment instrument insertion tube is fitted to at least a middle position. An imaging unit having a lens barrel of an objective lens and a solid-state imaging device is connected to the hard tip portion,
The treatment instrument insertion channel according to claim 1, wherein an opening portion of the connection pipe is disposed toward the imaging unit.   The treatment instrument insertion channel according to claim 1, wherein an outer diameter of the connection pipe is larger than an inner diameter of the treatment instrument insertion tube.   The treatment instrument insertion channel according to claim 1, wherein the open portion of the connection pipe is a cut plane parallel to the cylindrical tangential direction. The connecting pipe is composed of two parts in the axial direction, the open part and a closed part where the open part is not formed,
The closing portion is formed up to a position closer to the base end side than the treatment instrument outlet hole when the connection pipe is attached to the treatment instrument outlet hole,
The treatment instrument insertion according to claim 1, wherein when the treatment instrument insertion tube is fitted to the connection pipe, the treatment instrument insertion tube is fitted from the fitting side of the treatment instrument insertion tube to the position of the closing portion. Channel.

Images