JP2006122498A - Endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope where a flow rate of a liquid made to flow through a channel formed inside an insertion part can be increased without increasing the outer diameter of the distal end of the insertion part and which has a rational constitution where curving operability of the insertion part is not damaged. <P>SOLUTION: The endoscope is provided with a channel 56 formed of: a channel hole 57 formed at the distal end 11; and a flexible channel tube 60 which is connected with the channel hole, includes a curved part 12 and is arranged extending in the rear insertion part 2 from a curved part 12. The cross sectional shape of the channel hole 57 is formed to be flat in a direction expanding the arrangement space of an imaging unit 48 incorporated in the tip 11. The cross section of the channel tube 60 is formed nearly circular. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an endoscope including a channel in an insertion portion in which a bending portion is disposed following a distal end portion in which an imaging unit is built.

Japanese Patent Laid-Open No. 2002-51973 proposes a cross-sectional shape of a channel for inserting a treatment instrument of an endoscope formed into an ellipse or an oval over the entire length of the channel.
JP 2002-51973 A

  In the endoscope of Patent Document 1 described above, the cross-sectional shape of the channel is formed in an elliptical shape or an oval shape over the entire length of the channel. The reason for forming in this way is to allow the treatment instrument having a flat forceps cup to be inserted into the channel without increasing the thickness of the channel arranged in the insertion portion. It is not directly related to distribution performance. Moreover, when the channel tube has an elliptical or oval cross-sectional shape, when the insertion portion, particularly the bending portion, is strongly curved, the flat tube portion is compared with that of the channel tube having a circular cross-sectional shape, It becomes easy to be crushed or buckled to some extent. Further, as the use is repeated, the channel tube is likely to be deformed or broken.

  If the channel tube is deformed or creased, there is a disadvantage that the cross-sectional area of the channel tube at that portion is reduced. As a result, in the case of liquid feeding / perfusion through the channel tube, there is a drawback that the flow of fluid through the channel tube is hindered and the flow rate that can be flowed through the channel tube is reduced.

  In addition, since it is difficult to mold a flat channel tube, there is a problem that the cost of the channel tube increases.

  Furthermore, if the cross-sectional shape of the channel tube is elliptical or oval, it is easy to bend in the flat direction, but is difficult to bend in the direction perpendicular to it, and the propensity to bend easily according to the direction of bending. Varies depending on the bending direction, and the bending operability is impaired. In addition, when the bending direction changes, it is easy for the channel tube to move or rotate in the insertion portion and interfere with other built-in objects.

  By the way, when using an endoscope, a liquid such as physiological saline may be injected or perfused into a body cavity through a channel formed in an insertion portion of the endoscope. At this time, it is desired to increase the flow rate flowing through the channel in order to perform good observation and diagnosis with an endoscope. For this reason, it is conceivable to increase the cross-sectional area of the channel. However, if the cross-sectional area of the channel is increased, the insertion portion of the endoscope must be made thicker accordingly, and there is a strong demand for reducing the diameter of the insertion portion. It is difficult to realize as an endoscope.

  In the case of an electronic endoscope equipped with an image sensor, the largest factor that prevents the insertion portion from being reduced in diameter is the storage portion around the image sensor unit, and the distal end of the insertion portion incorporating the image pickup unit is the thickest. There was a situation that would become.

  Therefore, in consideration of the above circumstances, the present invention can increase the flow rate of the liquid flowing through the channel formed inside the insertion portion without particularly increasing the outer diameter of the distal end portion of the insertion portion. An object of the present invention is to provide an endoscope having a rational configuration that does not impair the bending operability of the insertion portion.

The invention according to claim 1 includes an insertion portion including a distal end portion and a curved portion connected to the distal end portion, a channel hole provided in the distal end portion, and a curved portion including the curved portion connected to the channel hole. And a channel formed by a flexible channel tube disposed in the insertion portion on the rear side, and the channel hole is flat in a direction to widen the arrangement space of the image pickup unit whose cross-sectional shape is incorporated in the distal end portion. The endoscope is characterized in that the channel tube has a substantially circular cross-sectional shape.
According to a second aspect of the present invention, there is provided an insertion portion including a distal end portion and a bending portion connected to the distal end portion, a channel hole provided in the distal end portion, and the bending portion including the bending portion connected to the channel hole. And a channel formed by a flexible channel tube disposed in the insertion portion on the rear side, and the channel hole is flat in a direction to widen the arrangement space of the image pickup unit whose cross-sectional shape is incorporated in the distal end portion. The endoscope is characterized in that the channel tube has a substantially circular cross-sectional shape, and the cross-sectional area of the channel hole is substantially the same as the cross-sectional area of the channel tube inner hole. .
According to a third aspect of the present invention, a main body of the tip portion is formed with a resin-made front frame, a metal connection pipe forming at least a part of the channel hole is attached to the front frame, and the connection pipe is inserted into the insertion portion. The endoscope according to claim 1, wherein the endoscope is connected to a ground member.
The invention according to claim 4 is the endoscope according to claim 3, wherein a part of the connection pipe is cut out.
According to a fifth aspect of the present invention, the cross-sectional shape of the connection pipe is an ellipse or an ellipse, the imaging unit is arranged in the minor axis direction, and light guides are provided on both left and right sides of the imaging unit intersecting the minor axis direction. The endoscope according to claim 1, 2, or 3, wherein the endoscope is arranged.

  According to the present invention, the channel can be rationally distributed in the insertion portion by changing the cross-sectional shape of the channel to efficiently use the space in the insertion portion and increase the perfusion rate without increasing the outer diameter of the insertion portion. Moreover, the bending operability of the insertion portion can be improved.

<First Embodiment>
Hereinafter, an electronic endoscope according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 6.

  FIG. 1 schematically shows the entire endoscope. As shown in FIG. 1, the endoscope 1 includes a long insertion portion 2 and an operation portion 3 provided at the proximal end of the insertion portion 2, and a universal cord 4 is connected to the operation portion 3. . A connector 5 to be described later is provided at the extended tip of the universal cord 4, and the endoscope 1 is connected to a light source device (not shown) by the connector 5. Connected to the connector 5 is a cable 7 leading to a video connector 6 that can be connected to the video processor. The connector 5 is provided with a light guide tube 8 for connection to a light source device (not shown). The video connector 6 is provided with a contact portion 9 for connection to the video processor side.

  The insertion portion 2 has a hard distal end portion 11 disposed at the distal end thereof, a bending portion 12 provided subsequent to the rear end of the distal end portion 11, and a flexible portion provided subsequent to the rear end of the bending portion 12. And a flexible tube portion 13 having a property. A grip portion 3a is formed on the operation portion 3 when the operator holds the endoscope 1. The air supply / water supply operation button 15 or the like is provided on a portion of the operation portion 3 located above the grip portion 3a. A suction operation button 16 for performing a suction operation is provided. The head of the operation unit 3 is provided with a plurality of remote switch buttons 17 for remotely operating the video processor described above. A pair of angle knobs 18 a and 18 b are provided on the side surface of the operation unit 3 as operation members for use when the bending portion 12 of the insertion portion 2 is bent. Each angle knob 18a, 18b is provided with a brake member for locking to the operation position.

  In the present embodiment, a brake knob 19a is provided corresponding to the angle knob 18a, and a brake lever 19b is provided corresponding to the angle knob 18b. In addition, a treatment instrument insertion port 20 is provided in a portion located below the grip portion 3a.

  Next, the configuration of the distal end portion 11 in the insertion portion 2 will be specifically described. As shown in FIGS. 2 to 5, the distal end portion 11 of the insertion portion 2 includes a distal end portion body (tip frame) 31 made of resin, and various members are assembled to the distal end portion body 31. It has become. The tip portion main body 31 is molded from an electrically insulating material as an integral member.

  As shown in FIG. 2A, the tip body 31 has one first mounting hole 35 for assembling an objective lens unit 32 to be described later, and a pair of illumination lenses arranged on the left and right as shown in FIG. Two second mounting holes 36 are provided as illumination lens housing holes for individually incorporating 34. The two second mounting holes 36 are arranged adjacent to the left and right of the first mounting hole 35. Each of the second mounting holes 36 penetrates the front end portion body 31 in the front-rear direction.

  Further, as shown in FIG. 2B, the second mounting hole 36 is formed by being arranged in parallel as a straight hole having the same diameter over the entire length in the front and rear direction. Claw-like protrusions 37 that protrude toward the center of the hole 36 are integrally formed at the edge of the opening portion of the second attachment hole 36. The protrusion 37 may be formed over the entire periphery of the tip opening or may be formed partially. The protrusion 37 is formed integrally with the tip end body 31, but may be provided on another member or another member constituting the tip end body 31.

  As shown in FIG. 2B, the illumination lens 34 is fitted into each of the second mounting holes 36 from the rear side, and then the tip portion of the light guide fiber bundle 38 as a light guide for guiding the illumination light is inserted. It is designed to be fitted and assembled. A protection tube 39 is fitted on the tip portion of the light guide fiber bundle 38, and a portion exposed from the protection tube 39 is bundled by a protection tube 40.

  This protective tube 39 is inserted into the second mounting hole 36. Then, the illumination lens 34 is positioned by being pushed in until the peripheral edge of the illumination lens 34 comes into contact with the back surface of the projection 37 in the tip opening. The illumination lens 34 and the protective tube 39 are substantially equal to the inner diameter of the second mounting hole 36, and the illumination lens 34 and the protective tube 39 can be inserted into the second mounting hole 36. Then, the tip end portions of the illumination lens 34 and the light guide fiber bundle 38 are fixed with an adhesive or the like while being positioned in the second mounting hole 36. The illumination lens 34 is attached to the second attachment hole 36 in a sealed state. In such a configuration, when the illumination lens 34 hits the projection 81 of the second mounting hole 36, the mounting position of the illumination lens 34 is determined in the front-rear position on the optical axis. In addition, the positioning of the illumination lens 34 does not depend on the operation of bonding the illumination lens 34 to the second mounting hole 36, and the position of the illumination lens 34 is determined by abutting the illumination lens 34 against the protrusion 81. Accordingly, the mounting and fixing position of the illumination lens 34 is accurately determined, and the assembly work of the illumination lens 34 is facilitated.

  In the embodiment described above, the illumination lens 34 is assembled by inserting the illumination lens 34 from the rear into the second mounting hole 36, but the illumination lens 34 is inserted from the opening formed on the side of the second mounting hole 36. Alternatively, a horizontal insertion type may be used in which the second attachment hole 36 is attached to the attachment position, and the opening is covered and closed.

  As shown in FIG. 2A, the distal end portion of the objective lens unit 32 is fitted into the first mounting hole 35, and the objective lens unit (imaging optical system) 32 is bonded and fixed to the distal end portion body 31. . The objective lens unit 32 includes a lens frame 41 and an image sensor holder frame 42. The front end portion of the imaging element holder frame 42 is fitted on the outer periphery of the rear end portion of the lens frame 41, and both are fixed by an adhesive 43 after positioning adjustment. The lens frame 41 located on the front end side holds the objective lens group 45, and the image sensor holder frame 42 located on the rear end side holds an image pickup lens 46 and an image pickup element 47 such as a CCD, and an image pickup unit 48 described later. Constitute. The imaging unit 48 is larger than the objective lens unit (imaging optical system) 32.

  The image pickup unit 48 is located behind the image pickup element 47, an attached circuit 53 including a circuit board 51 and a circuit element 52 is arranged, and a connection portion 55 of a signal cable 54 is arranged behind the attached circuit 53. . That is, the image pickup element 47 of the image pickup unit 48 is disposed on the optical axis of the objective lens unit 32 and is located behind the objective lens unit 32. Further, an attached circuit 53 is located behind the image sensor 47, and a connecting portion 55 of the signal cable 54 is arranged behind the attached circuit 53. Although it is arranged side by side so as to overlap in the axial direction of the insertion portion 2 so as not to spread in the radial direction of the distal end portion 11 from the objective lens unit 32 to the imaging unit 48, the peripheral portion of the imaging element 47 is still accommodated. The part occupies the largest installation space. The signal cable 54 is much thinner than the imaging unit 48.

  Further, as shown in FIG. 2A and FIGS. 3 to 5, a channel hole 57 that forms a distal end opening portion of a channel 56 formed in the insertion portion 2 is opened in the distal end portion body 31 of the distal end portion 11. Is formed. The objective lens unit 32 and the illumination lens 34 described above are disposed below the channel hole 57.

  As shown in FIG. 2A, in the tip body 31, the inner part (rear end part) of the channel hole 57 is formed as a hole 58 having a larger diameter than the other part. The distal end portion of the metal connection pipe 59 is closely fitted in the large-diameter hole 58, and the connection pipe 59 is fixed to the distal end portion body 31 by adhesion or the like. The distal end portion of the flexible channel tube 60 is fitted on the outer periphery of the rear end portion of the connection pipe 59 and is fixed by bonding or the like. A channel 61 is formed so as to extend over the channel hole 57 (including the connection pipe 59) of the tip end body 31 and the channel tube 60.

  The channel tube 60 is guided to the operation unit 3 through each of the bending portion 12 and the flexible tube portion 13 of the insertion unit 2 and connected to a base of the treatment instrument insertion port 20 in the operation unit 3 (see FIG. 1). .

  As shown in FIG. 3, the cross-sectional shape of the channel hole 57 of the tip end body 31 is a horizontally long ellipse or ellipse, a horizontally long shape, and a horizontally long flat shape. The cross-sectional shape of the inner hole of the connection pipe 59 that forms a part of the channel hole 57 is also a horizontally long flat shape formed in the same cross-sectional shape as the channel hole 57. That is, the cross-sectional shape of the channel hole 57 and the cross-sectional shape of the inner hole of the connection pipe 59 are the same. In addition, the cross-sectional area of the channel hole 57 and the cross-sectional area of the inner hole of the connection pipe 59 are substantially matched.

  As shown in FIGS. 4 and 5, the channel hole 57 has a flat shape so that the cross-sectional shape of the channel hole 57 increases the arrangement space of the imaging unit 48 incorporated in the distal end portion 11. The cross-sectional shape of the channel hole 57 is an ellipse or an ellipse, and the imaging unit 48 is arranged in the minor axis direction, intersects the minor axis direction, passes through the imaging unit 48, and The light guide fiber bundle 38 is arranged on both the left and right sides.

  On the other hand, as shown in FIG. 6, the channel tube 60 has a circular cross-sectional shape, has a uniform diameter and shape in all directions, and is formed so that the bending characteristics are equal in all directions. The cross-sectional area of the channel tube 60 is the same as the cross-sectional area of the channel portion at the tip 11, that is, the cross-sectional area of the channel hole 57 and the cross-sectional area of the inner hole of the connection pipe 59. Since the cross-sectional area of the channel 61 does not decrease even at the tip portion 11, the flow rate that can flow through the channel 61 does not decrease.

The channel tube 60 may be formed of a resin tube. However, a flexible core material such as a braid formed by knitting or assembling metal wires or a flex formed by a metal coil is used as the core material. Was formed by a flexible tube having a sandwich structure sandwiched between soft inner and outer resin layers.
Further, at least the outer periphery located in the region of the bending portion 12 is covered with a protective flex helical tube 62.

  The connection pipe 59 is joined to the inner surface of the most advanced node ring 75 in the bending portion 12 described later by soldering or the like, and is electrically connected to the node ring 75. Since the connection pipe 59 here is a conductive member, leakage of high-frequency output is released to the ground member of the insertion portion 2 made of a conductive member such as the node ring 75 in the bending portion 12 through the connection pipe 59. Can do.

  For this reason, in an electronic endoscope in which treatment is performed with a high-frequency treatment tool in a conductive liquid such as physiological saline, when the distal end portion body 31 is made of metal, a leakage current of high-frequency output is transmitted through the endoscope. In order to easily make a complicated tip body 31 with a resin member as in this embodiment and reduce the cost of the endoscope, the tip body 31 is made of a resin member. Even in this case, it is difficult for the leakage current of the high-frequency output to flow into the image sensor 47 through the lens frame 41, and the generation of noise can be suppressed.

  As shown in FIG. 2A, the bending portion 12 in the insertion portion 2 includes a bending main body 76 that is formed in a substantially tubular shape as a whole by a plurality of node rings 75, and a covering member described later is provided on the outer periphery of the bending main body 76. 74 is applied. The node rings 75 constituting the curved main body 76 are arranged in a line in the longitudinal axis direction of the insertion portion 2, and adjacent ends of the node rings 75 are alternately or alternately arranged in a rivet-like pin in the left-right position or the vertical position. 77 are pivotally attached to each other. Here, they are pivotally supported by rivet-shaped pins 77 only in the left and right positions. For this reason, each node ring 75 can be rotated in the vertical direction around the pin 77 as a center of rotation, and the entire bending body 76 can be bent in the vertical direction.

  As shown in FIG. 2A, the most advanced node ring 75 is fixed to the distal end portion body 31 in the distal end portion 11 of the insertion portion 2. Further, the node ring 75 at the rearmost end is connected and fixed to the distal end of the flexible tube portion 13 shown in FIG. 2 directly or via a connecting tube.

  As shown in FIG. 6, two operation wires 81 a and 81 b are inserted from the flexible tube portion 13 to the bending portion 12 in the insertion portion 2 in order to bend the bending portion 12 up and down. The distal ends of these operation wires 81 a and 81 b are fixedly connected to the distal end side portion of the bending portion 12, for example, the most advanced node ring 75 or the distal end portion main body 31. Further, the distal end fixing portions of the operation wires 81a and 81b are respectively arranged at positions substantially corresponding to the vertical and horizontal rotation centers of the node ring 75.

  The proximal sides of the operation wires 81a and 81b are guided into the operation section 3 through wire guides 82a and 82b and flexible wire guide tubes, which correspond individually to each other, and the respective operation wires 81a and 81b are guided. The forward and backward movements are individually guided, and the bending operation force by the operation wires 81 a and 81 b is transmitted to the bending portion 12. When the bending portion 12 of the insertion portion 2 is bent, a wire push / pull operation device (not shown) incorporated in the operation portion 3 may be operated by the angle knobs 18a and 18b of the operation portion 3.

  As shown in FIG. 2A, the imaging unit 48 is surrounded by a cylindrical tip cover (second front frame) 65 attached to the tip body 31. The distal end cover 65 is positioned and fixed by fitting the distal end portion thereof to the outer peripheral portion of the rear end of the distal end main body 31. Both the tip body 31 and the tip cover 65 are fixed by soldering, bonding, or the like in a positioned state.

  As shown in FIGS. 2 and 4 to 6, the covering member 74 is covered from the distal end portion 11 to the bending portion 12 in the insertion portion 2, and the distal end portion of the covering member 74 is the distal end portion main body. 31 and is fastened with a thread 78, and an adhesive 79 is applied to the thread winding portion.

  As described above, in this embodiment, the cross-sectional shape of the channel hole formed in the distal end portion 11 is flattened so as to widen the arrangement space of the imaging unit 48 incorporated in the distal end portion 11, and the channel tube 60. The cross-sectional shape is formed in a substantially circular shape. The channel 61 can be formed as thick as possible without increasing the outer diameter of the tip.

  By the way, in the case of the electronic endoscope provided with the image pickup device 47, the factor that restricts the diameter reduction of the insertion portion 2 is the storage portion around the image pickup device 47, while the subsequent insertion portion 2 has a built-in component. Often there is room in the installation space. Therefore, only the cross-sectional shape of the channel hole 57 including the connection pipe 59 juxtaposed with the image sensor 47 is a flat cross-sectional shape, and the cross-sectional shape of the channel tube 60 is substantially circular. For this reason, the cross-sectional area of the channel hole 57 can be ensured and the flow rate flowing through the channel 61 can be increased without increasing the thickness of the distal end portion 11 into which the imaging unit 48 is incorporated.

  In addition, since the cross-sectional shape of the channel tube 60 is circular, even when the bending portion 12 is strongly bent, it is difficult to be crushed or buckled as compared to the flat tube, and the channel tube 60 can be deformed or folded. It is hard to stick. As a result, it is possible to eliminate the inconvenience that the cross-sectional area of the channel tube 60 decreases due to deformation or folds of the channel tube 60 during use. When fluid is fed / perfused through the channel tube 60, the fluid flows smoothly. Further, since the cross-sectional shape of the channel tube 60 is circular, the channel tube 60 can be easily molded as compared with the case where a flat channel tube is used. For this reason, the cost of the channel tube 60 can be reduced.

  Furthermore, when the cross-sectional shape of the channel tube 60 is flat, it is easy to bend in the flat direction, but it is difficult to bend in the direction orthogonal thereto, and the propensity to bend differs according to the direction of the curve, Although the operability is impaired, in this embodiment, since the cross-sectional shape of the channel tube 60 is substantially circular, the bending direction does not change even when the bending direction is changed, and the channel tube 60 is inserted into the insertion portion 2 when being bent. There is also a low rate of interference with other built-in objects by moving or rotating with. Further, if the cross-sectional area of the channel hole 57 is formed to be substantially the same as the cross-sectional area of the inner hole of the channel tube 60, it is possible to achieve a good For diagnosis, it is convenient to secure a flow rate to flow through the channel 61.

<Second Embodiment>
As shown in FIGS. 7 and 8, the tip end main body 31 is partly cut out from the storage chamber 90 in which the imaging unit 48 is disposed to the second mounting hole 36 adjacent thereto, and the first notch A part of the protective tube 39 of the light guide fiber bundle 38 that protrudes to the portion 91 is also cut away, and one edge portion of the imaging unit 48 is located in both of the matching cutout portions 91 and 92, or It has entered (see FIG. 8). For this reason, when disposing the most bulky imaging unit 48 in the distal end main body 31, interference between the storage chamber 90 and the protective tube 39 is reduced as much as possible, and a plurality of adjacent members can be incorporated in a compact manner.

Since this configuration can increase the thickness of the protective tube 39, the illumination lens 34 and the protective tube 39 of the light guide fiber bundle 38 are inserted into the second mounting hole 36 from the rear as in the case of the first embodiment described above. It is suitable for the method of inserting and assembling.
Since other than this is the same as the first embodiment described above, the description thereof is omitted.

<Third Embodiment>
As described above, the present embodiment is usually adopted in an endoscope in which the distal end portion 11 of the insertion portion 2 incorporates an imaging unit 48 incorporating an imaging element such as a light guide fiber bundle 38, a channel 56, and a CCD. An image sensor such as a CCD incorporated in the image pickup unit 48 is vertically long so as not to create a useless space, and this type of image sensor unit 95 is vertically long as shown in FIG. It is arranged and used.

  However, in the case where the vertically long image pickup device portion 95 is diverted to a device in which the image pickup unit 48 incorporating the image pickup device such as the channel 56 and CCD is arranged as shown in FIG. 10B. As shown in FIG. 10B, a useless space is created.

  Therefore, in the present embodiment, as shown in FIG. 9, a type that is arranged above and below and used in a horizontal direction is used. Then, in the processor that performs image processing of the signal of the image sensor unit 95 arranged in the horizontal direction, the process of rotating the direction of the image by 90 ° is performed.

  In this way, the image sensor unit 95 of a type that is normally used by being arranged one above the other can be arranged and used in the horizontal direction, so that it is possible to arrange it in a compact manner without creating a useless space. This configuration may be applied to the above-described first embodiment as shown in FIG.

  In addition, this invention is not limited to the thing of embodiment mentioned above, It can apply also to another form.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic explanatory drawing of the whole electronic endoscope which concerns on the 1st Embodiment of this invention. The longitudinal cross-sectional view of the front-end | tip part in the insertion part of the said electronic endoscope. The front view of the front-end | tip part in the insertion part of the said electronic endoscope. The cross-sectional view of the part along the AA line in Fig.2 (a). FIG. 3 is a cross-sectional view of a portion along line BB in FIG. The cross-sectional view of the portion along the line CC in FIG. The longitudinal cross-sectional view of the front-end | tip part in the insertion part of the electronic endoscope which concerns on the 2nd Embodiment of this invention. Similarly, the cross-sectional view of the front-end | tip part in the insertion part of the electronic endoscope which concerns on the 2nd Embodiment of this invention. The longitudinal cross-sectional view which shows arrangement | positioning of the component of the front-end | tip part in the insertion part of the electronic endoscope which concerns on the 3rd Embodiment of this invention. (A) (b) is a longitudinal cross-sectional view which shows the other example of arrangement | positioning of the components of the front-end | tip part in the insertion part of an electronic endoscope.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Endoscope, 2 ... Insertion part, 3 ... Operation part, 11 ... Tip part 12 ... Curved part, 13 ... Flexible pipe part, 31 ... Tip part main body 32 ... Objective lens unit, 34 ... Illumination lens, 35 ... 1st mounting hole 36 ... 2nd mounting hole, 37 ... protrusion, 38 ... light guide fiber bundle 39 ... protective tube, 40 ... protective tube, 41 ... lens frame 42 ... imaging element holder frame, 45 ... objective lens group, 46 ... Imaging lens 47 ... Imaging device, 48 ... Imaging unit, 54 ... Signal cable 56 ... Channel, 57 ... Channel hole, 59 ... Connection pipe 60 ... Channel tube, 61 ... Channel

Claims (5)

An insertion portion including a distal end portion and a bending portion connected to the distal end portion;
A channel hole provided in the distal end portion and a channel formed by a flexible channel tube connected to the channel hole and including the bending portion and disposed from the bending portion to a rear insertion portion. ,
The channel hole has a flat shape in a direction to expand the arrangement space of the image pickup unit whose cross-sectional shape is incorporated in the tip portion,
An endoscope characterized in that the channel tube has a substantially circular cross section. An insertion portion including a distal end portion and a bending portion connected to the distal end portion;
A channel hole provided in the distal end portion and a channel formed by a flexible channel tube connected to the channel hole and including the curved portion and disposed from the curved portion to the rear insertion portion. ,
The channel hole has a flat shape in a direction to expand the arrangement space of the image pickup unit whose cross-sectional shape is incorporated in the tip portion,
The channel tube has a substantially circular cross-sectional shape,
Furthermore, the endoscope is characterized in that the cross-sectional area of the channel hole is formed substantially the same as the cross-sectional area of the channel tube inner hole.   The main body of the tip is formed with a resin-made front frame, a metal connection pipe that forms at least a part of the channel hole is attached to the front frame, and the connection pipe is connected to the ground member of the insertion section. The endoscope according to claim 1 or 2, wherein the endoscope is characterized.   The endoscope according to claim 3, wherein a part of the connection pipe is cut out.   A cross-sectional shape of the connection pipe is an ellipse or an ellipse, the imaging unit is arranged in the minor axis direction, and light guides are arranged on both the left and right sides of the imaging unit intersecting the minor axis direction. The endoscope according to claim 1, claim 2 or claim 3.

Images