Endoscopy

Abstract

To provide an endoscope that enables treatment by a treatment instrument to be executed appropriately.SOLUTION: An observation window 46 is principally disposed in a proximity area 70E, a first treatment instrument lead-out port 52 is principally disposed in a fourth quadrant 70D, a second treatment instrument lead-out port 54 is principally disposed in a third quadrant 70C, and the upper end position 54B of the second treatment instrument lead-out port 54 is disposed above the upper end position 52B of the first treatment instrument lead-out port 52.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an endoscope, and more particularly to an endoscope having a treatment tool outlet port at the distal end of an insertion section. [Background technology]

[0002] In endoscopes, various treatments are performed on a subject by introducing various treatment tools through a treatment tool inlet provided in the operation section and leading the treatment tools out through a treatment tool outlet opening at the tip of the insertion section. Endoscopic submucosal dissection (ESD) is known as one example of such treatments.

[0003] Patent Document 1 discloses an endoscope that performs treatment by introducing different types of treatment tools from two treatment tool outlets that open at the tip of an insertion section.

[0004] The endoscope of Patent Document 1 has two treatment tool outlets, a cutting treatment tool outlet for outletting a cutting treatment tool that cuts internal tissue, and a capturing treatment tool outlet for outletting a capturing treatment tool that captures the cut tissue. The cutting treatment tool outlet and the capturing treatment tool outlet are open and disposed at positions sandwiching an observation window in the diagonal direction of the visual field mask. A cleaning water outlet for ejecting cleaning water is disposed at a position closer to the cutting treatment tool outlet than the intermediate position between the cutting treatment tool outlet and the capturing treatment tool outlet. This cleaning water outlet ejects cleaning water in a direction substantially parallel to the direction in which the treatment tool is ejected from the cutting treatment tool outlet. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2002-330920 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the endoscope of Patent Document 1, in the image of the inside of the subject obtained through the observation window, the capture treatment tool protruding from the capture treatment tool protruding port is observed as an image appearing from the top of the screen and moving toward the center of the screen. Therefore, from the viewpoint of the surgeon performing treatment while watching the image, the capture treatment tool may get in the way and make it difficult to see the lesion. In addition, when the capture treatment tool is raised (curved) when lifting the lesion with the capture treatment tool, for example, the capture treatment tool may be projected large in the center of the screen, so in this case too, the capture treatment tool may get in the way and make it difficult to see the lesion. As a result, the endoscope of Patent Document 1 may make it difficult to perform treatment with the cutting treatment tool accurately.

[0007] The present invention has been made in consideration of the above circumstances, and provides an endoscope that enables treatment with a treatment tool to be performed accurately. [Means for solving the problem]

[0008] In order to achieve the object of the present invention, an endoscope according to the present invention is provided with an observation window for observing inside a subject, which is provided on a distal end surface of an insertion section which is bendable in the up-down and left-right directions, a first treatment tool outlet provided on the distal end surface and capable of leading out a first treatment tool, and a second treatment tool outlet provided on the distal end surface and capable of leading out a second treatment tool, and when the distal end surface is viewed from the front, of two axes which pass through the center of the distal end surface and are perpendicular to each other, an axis parallel to the left-right direction is defined as a first axis, and an axis parallel to the up-down direction is defined as a second axis, and the distal end is determined by the first axis and the second axis. If the surface is divided into four divided regions, with the upper right divided region being the first quadrant, the upper left divided region being the second quadrant, the lower left divided region being the third quadrant, and the lower right divided region being the fourth quadrant, the observation window will be primarily located in the proximal region of the first quadrant that is close to the first axis, the first treatment instrument outlet will be primarily located in the fourth quadrant, the second treatment instrument outlet will be primarily located in the third quadrant, and the upper end position of the second treatment instrument outlet in the direction of the second axis will be located higher than the upper end position of the first treatment instrument outlet in the direction of the second axis.

[0009] In one aspect of the present invention, the observation window is preferably disposed mainly in a central region that is a region closer to the center than the outer periphery of the tip surface.

[0010] In one aspect of the present invention, the second treatment tool outlet has a larger diameter than the first treatment tool outlet.

[0011] In one aspect of the present invention, it is preferable that the distance between the center of the observation window and the center of the second treatment tool outlet is longer than the distance between the center of the observation window and the center of the first treatment tool outlet.

[0012] In one aspect of the present invention, it is preferable that the distance between the center of the first treatment tool outlet and the center of the second treatment tool outlet is longer than the distance between the center of the observation window and the center of the first treatment tool outlet.

[0013] In one form of the present invention, a forward water supply port is provided on the tip surface for spraying liquid toward an observation site within a subject, and it is preferable that the center position of the forward water supply port in the direction of the second axis is located between the center position of the observation window and the center position of the first treatment tool outlet in the direction of the second axis.

[0014] In one embodiment of the present invention, it is preferable that the forward water supply port is offset to the outer periphery of the tip face opposite the center of the tip face with respect to a line connecting the center of the observation window and the center of the first treatment tool outlet.

[0015] In one aspect of the present invention, the front water inlet is preferably disposed mainly in the fourth quadrant.

[0016] In one embodiment of the present invention, it is preferable that the second quadrant has an air / water nozzle.

[0017] In one form of the present invention, the distal end face has a first illumination window and a second illumination window, the first illumination window and the second illumination window being respectively arranged on the outer periphery of the distal end face opposite the center of the distal end face with respect to the observation window, and it is preferable that there is no overlapping area between a first region surrounded by straight lines connecting the center of the observation window and the centers of the first illumination window and the second illumination window and a second region surrounded by straight lines connecting the center of the observation window and the centers of the first treatment tool outlet and the second treatment tool outlet.

[0018] In one form of the present invention, the tip surface is provided with a forward water inlet for spraying liquid toward an area to be observed within a subject, and the tip surface preferably has a first surface and a second surface protruding from the first surface toward the tip of the insertion portion, and the forward water inlet is preferably located on the first surface and an observation window is preferably located on the second surface.

[0019] In one aspect of the present invention, the first illumination window is preferably disposed on the second surface.

[0020] In one embodiment of the present invention, it is preferable that the second illumination window is offset to the outer periphery of the tip face opposite the center of the tip face with respect to a line connecting the center of the observation window and the center of the air and water nozzle.

[0021] In one aspect of the present invention, the second illumination window is preferably disposed on the second axis. Effect of the Invention

[0022] According to the present invention, treatment using a treatment tool can be performed accurately. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a configuration diagram of an endoscope system including an endoscope according to an embodiment. [Diagram 2] FIG. 2 is a front view of the tip of the insertion section. [Diagram 3] FIG. 3 is a front view of the tip of the insertion section. [Figure 4]FIG. 4 is an explanatory diagram showing the procedure of a treatment method in ESD using the endoscope of the embodiment. [Diagram 5] FIG. 5 is an explanatory diagram showing the procedure of a treatment method in ESD using the endoscope of the embodiment. [Figure 6] FIG. 6 is an explanatory diagram showing the procedure of a treatment method in ESD using the endoscope of the embodiment. [Figure 7] FIG. 7 is an explanatory diagram showing the procedure of a treatment method in ESD using the endoscope of the embodiment. [Figure 8] FIG. 8 is an example of a biometric image displayed on a display. [Figure 9] FIG. 9 is a diagram showing an observation image captured by the observation optical system. [Figure 10] FIG. 10 is a schematic cross-sectional view of the operation portion at hand and the bending portion. [Figure 11] FIG. 11 is a diagram showing the relationship between the torque generated when bending the bending portion and the bending angle of the bending portion. [Figure 12] FIG. 12 is a diagram showing a connection form of a plurality of bending pieces that constitute the bending portion. [Figure 13] FIG. 13 is a cross-sectional view showing the internal structure of the bending portion. [Figure 14] FIG. 14 is a cross-sectional view showing the internal structure of the bending portion. [Figure 15] FIG. 15 is a cross-sectional view showing the internal structure of the bending portion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, an embodiment of an endoscope of the present invention will be described with reference to the accompanying drawings.

[0025] 1 is a configuration diagram of an endoscope system 12 including an endoscope 10 according to an embodiment of the present invention. The endoscope system 12 includes the endoscope 10, an endoscope processor device 14, and a display 16.

[0026] The endoscope 10 includes a hand-operated portion 18 and an insertion portion 20 that is provided on the distal end side of the hand-operated portion 18 and is inserted into a subject.

[0027] The insertion section 20 has a long axis Ax extending from the base end to the tip end, and is provided with a flexible section 22, a bending section 24, and a tip section 26 in that order from the base end to the tip end.

[0028] A pair of angle knobs 28, 30 for bending the bending portion 24 are disposed on the hand-operated operation unit 18. The pair of angle knobs 28, 30 are provided so as to be freely rotatable on the same axis. The angle knobs 28, 30 and the bending portion 24 are connected by four angle wires (not shown) inserted through the flexible portion 22, and the angle wires are pushed and pulled by rotating the angle knobs 28, 30, thereby bending the bending portion 24 in the up-down and left-right directions. The hand-operated operation unit 18 is also provided with an air / water supply button 31A and a suction button 31B.

[0029] In this specification, a three-dimensional orthogonal coordinate system of three mutually orthogonal axial directions (X-axis, Y-axis, and Z-axis) is used for explanation. That is, when the angle knob 28 for vertical operation is rotated in the UP direction as viewed from the distal end 26 of the handheld operation unit 18, the upward direction is the Z(+) direction, and the opposite downward direction is the Z(-) direction. When the angle knob 30 for horizontal operation is rotated in the R direction, the rightward direction is the X(+) direction, and the leftward direction is the X(-) direction. At that time, the forward direction (the direction toward the distal end in the direction of the long axis Ax) is the Y(+) direction, and the rearward direction (the direction toward the base end in the direction of the long axis Ax) is the Y(-) direction. The Y-axis direction, which includes the Y(+) direction and the Y(-) direction, is parallel to the direction of the long axis Ax.

[0030] A base end of a universal cable 32 is connected to the hand operation unit 18, and a connector device 34 is provided at the tip end of the universal cable 32. The connector device 34 is connected to the processor device 14 for the endoscope.

[0031] The endoscope processor 14 includes a light source device 36 and an image processing device 38. The light source device 36 includes a processor-side connector 37 to which the connector device 34 is connected. The image processing device 38 is connected to a display 16 that displays an image processed by the image processing device 38. According to the endoscope system 12, light from the light source device 36 is transmitted through an optical fiber cable (not shown) and is irradiated forward (Y(+) direction) from illumination windows 42, 44 provided on a distal end surface 40 (see FIG. 2) of the distal end portion 26. Image light incident from an observation window 46 (see FIG. 2) provided on the distal end surface 40 is received by an image sensor (not shown) through an observation optical system (not shown) provided behind the observation window 46 (Y(-) direction), for example. The electric signal photoelectrically converted by the image sensor is processed by the image processing device 38 and displayed on the screen of the display 16 as an image inside the subject (hereinafter also referred to as a "biological image"). In the display 16, the up-down direction in which the bending portion 24 bends is aligned with the vertical direction within the screen, and the left-right direction in which the bending portion 24 bends is aligned with the horizontal direction within the screen.

[0032] The proximal operation section 18 in FIG. 1 is provided with a first treatment tool introduction port 48 through which the first treatment tool can be introduced, and a second treatment tool introduction port 50 through which the second treatment tool can be introduced. The insertion section 20 is also provided with a first treatment tool channel and a second treatment tool channel (not shown). The base end of the first treatment tool channel is connected to the first treatment tool introduction port 48, and the tip end is connected to the first treatment tool outlet 52 opened on the tip surface 40 shown in FIG. 2. The base end of the second treatment tool channel is connected to the second treatment tool introduction port 50 shown in FIG. 1, and the tip end is connected to the second treatment tool outlet 54 opened on the tip surface 40 in FIG. 2. As an example of the first treatment tool, a cutting treatment tool (for example, high-frequency scissors forceps, ESD knife, biopsy forceps) that cuts (incises) tissue in the body is used. As the second treatment tool, a treatment tool having multiple functions is used. Examples of such treatment tools include grasping forceps having a grasping function and a bending function, an endoscopic suture instrument having a suturing function, etc. The above is an overview of the endoscope 10.

[0033] Here, in a forward-viewing endoscope such as the endoscope 10 in this example, in which the tip 26 of the insertion section 20 is provided with an observation window 46 and two treatment tool outlets (in this example, a first treatment tool outlet 52 and a second treatment tool outlet 54), the following points are required to enable accurate treatment using two treatment tools.

[0034] That is, the surgeon who operates the endoscope 10 treats the lesion by leading out two treatment tools from the first treatment tool outlet 52 and the second treatment tool outlet 54 while watching the living body image displayed on the display 16. For this reason, it is necessary to avoid the two treatment tools getting in the way of the living body image and making it difficult to see the lesion. Therefore, the endoscope 10 of this example is capable of accurately performing treatment using two treatment tools by arranging components such as the observation window 46, the first treatment tool outlet 52, and the second treatment tool outlet 54 provided on the distal end surface 40 of the distal end portion 26 shown in FIG. 2 in suitable positions as shown in FIG. 2. An example of suitable positions for the above components will be described in detail below.

[0035] Fig. 2 is a front view of tip portion 26. That is, Fig. 2 is a view of tip surface 40 of tip portion 26 viewed from the Y(+) side toward the Y(-) side. Fig. 3 is a front view of tip portion 26 similar to Fig. 2, but is used to supplement the explanation of the arrangement of components.

[0036] As shown in Fig. 2, the distal end surface 40 of the distal end portion 26 is provided with illumination windows 42 and 44, an observation window 46, a first treatment tool outlet 52, a second treatment tool outlet 54, a front water supply port 56, and an air and water supply nozzle 58 at predetermined positions. Here, the illumination window 42 corresponds to the first illumination window of the present invention, and the illumination window 44 corresponds to the second illumination window of the present invention. Also, the observation window 46 corresponds to the observation window of the present invention, the first treatment tool outlet 52 corresponds to the first treatment tool outlet of the present invention, and the second treatment tool outlet 54 corresponds to the second treatment tool outlet of the present invention. Furthermore, the front water supply port 56 corresponds to the front water supply port of the present invention, and the air and water supply nozzle 58 corresponds to the air and water supply nozzle of the present invention.

[0037] As described above, the observation window 46 is a window for observing the inside of the subject located in front of the tip portion 26 (Y(+) direction), and the illumination windows 42, 44 are arranged to sandwich this observation window 46. Here, for example, when the diameter of the tip portion 26 is 12.5 to 13.0 mm, the observation window 46 and the illumination windows 42, 44 are each formed to have a diameter of about 1.5 to 2.0 mm, for example.

[0038] The first treatment tool outlet 52 is an opening through which the cutting tool (first treatment tool) described above can be led forward. The second treatment tool outlet 54 is an opening through which the grasping forceps (second treatment tool) described above can be led forward. The second treatment tool outlet 54 is formed with a diameter of about 3.5 to 4.0 mm, for example, in order to pass the grasping forceps having a larger diameter than the cutting tool. That is, the diameter of the second treatment tool outlet 54 is formed larger than the diameter of the first treatment tool outlet 52 (about 3.0 to 3.5 mm, for example), which is only required for the cutting tool to pass through. The first treatment tool outlet 52 also functions as a suction port for sucking liquid, etc., from within the subject by operating the suction button 31B in FIG. 1.

[0039] The front water supply port 56 is an opening for injecting liquid toward an observation site (e.g., a lesion) in a subject, and is formed with a diameter of about 1.0 to 1.5 mm, for example. The front water supply port 56 is connected to a water supply connector 35 provided in the connector device 34 (see FIG. 1) via a water supply tube (not shown). A water supply device (not shown) is connected to the water supply connector 35, and liquid is supplied to the front water supply port 56 via the water supply tube by driving the water supply device.

[0040] The air and water nozzle 58 is a nozzle that sprays liquid and air mainly toward the observation window 46. Liquid or air is selectively supplied to the air and water nozzle 58 by operating the air and water button 31A shown in FIG.

[0041] Here, as shown in Fig. 2, when the distal end surface 40 is viewed from the front, of two axes that pass through the center C of the distal end surface 40 and are perpendicular to each other, the axis parallel to the left-right direction is the horizontal axis H, and the axis parallel to the up-down direction is the vertical axis V. Among the divided regions obtained by dividing the distal end surface 40 into four by the horizontal axis H and the vertical axis V, the upper right divided region is the first quadrant 70A, the upper left divided region is the second quadrant 70B, the lower left divided region is the third quadrant 70C, and the lower right divided region is the fourth quadrant 70D. In this case, the observation window 46 is disposed in the adjacent region 70E (see Fig. 3) adjacent to the horizontal axis H in the first quadrant 70A, the first treatment tool outlet 52 is disposed in the fourth quadrant 70D, and the second treatment tool outlet 54 is disposed in the third quadrant 70C. An upper end position 54B in the direction of the vertical axis V of the second treatment tool outlet 54 is disposed above an upper end position 52B in the direction of the vertical axis V of the first treatment tool outlet 52. Here, the horizontal axis H corresponds to the first axis of the present invention, and the vertical axis V corresponds to the second axis of the present invention.

[0042] The above-mentioned "proximal region 70E" refers to the tip surface region on the horizontal axis H side of the tip surface region obtained by dividing the first quadrant 70A into two at a midpoint in the direction of the vertical axis V (the midpoint of the distance from the center C of the tip surface 40 to the upper end 40D in the direction of the vertical axis V), as shown in FIG.

[0043] Next, an example of a treatment method using the endoscope 10 of the embodiment will be described with reference to Fig. 4 to Fig. 7. Fig. 4 to Fig. 7 show the procedure of a treatment method in ESD. As shown in Fig. 7, a high-frequency scissors forceps 100 having a pair of openable and closable claws 102 at the tip is used as the first treatment tool. The pair of claws 102 are opened and closed by an operation unit (not shown) of the high-frequency scissors forceps 100. When the pair of claws 102 are closed and the living tissue is grasped by the pair of claws 102, a high-frequency current is passed between the pair of claws 102 to cauterize and incise the living tissue.

[0044] As shown in Fig. 4, a grasping forceps 200 having a bending portion 202 and a pair of gripping portions 204 at a distal end thereof is used as the second treatment tool. The bending portion 202 is bent by an operating portion (not shown) of the grasping forceps 200, and the pair of gripping portions 204 are opened and closed by the operating portion.

[0045] First, the insertion section 20 of the endoscope 10 shown in Fig. 1 is orally inserted into the subject. Then, as shown in Fig. 4, when the tip section 26 is positioned to the side of the lesion 300 of the mucosal layer, the high-frequency scissors forceps 100 (see Fig. 7) is inserted into the first treatment tool channel from the first treatment tool introduction port 48 of the endoscope 10 (see Fig. 1). Then, the grasping forceps 200 (see Fig. 4) is inserted into the second treatment tool channel from the second treatment tool introduction port 50, and the pair of grasping portions 204 and the bending portion 202 of the grasping forceps 200 are led forward from the second treatment tool lead-out port 54 as shown in Fig. 4. Then, as shown in Figs. 4 and 5, the operating portion (not shown) of the grasping forceps 200 is operated to grasp the lesion 300 with the pair of grasping portions 204.

[0046] 6, the operating portion (not shown) of the grasping forceps 200 is operated to bend the bending portion 202 upward (Z(+) direction), thereby raising the pair of grasping portions 204, and the lesion portion 300 grasped by the pair of grasping portions 204 is lifted upward.

[0047] Next, in a state in which the lesion 300 is lifted as shown in Fig. 6, the high-frequency scissors forceps 100 inserted into the first treatment tool channel is led out forward from the first treatment tool outlet 52 as shown in Fig. 7. Then, the pair of claws 102 of the high-frequency scissors forceps 100 are advanced to a lower portion of the lesion 300, and the lower portion of the lesion 300 is incised by the pair of claws 102. Then, when the lesion 300 is completely incised, the grasping forceps 200 is retracted to the Y(-) side while grasping the lesion 300 with the pair of grasping parts 204, and the lesion 300 is taken out of the endoscope 10. The above is an example of a treatment method in ESD.

[0048] Fig. 8 shows an example of a biometric image 400 displayed on the display 16 in the above-mentioned procedure. In explaining the biometric image 400 shown in Fig. 8, the so-called clock position expressed from 1 o'clock to 12 o'clock will be used in addition to the up-down (Z-axis) and left-right (X-axis) positions.

[0049] According to the biological body image 400 in Fig. 8, the high-frequency scissors forceps 100 led out from the first treatment tool outlet 52 (see Fig. 2) is observed as an image moving from approximately the 6 o'clock position at the bottom of the screen toward the lesion 300 at the center of the screen. Moreover, the grasping forceps 200 led out from the second treatment tool outlet 54 (see Fig. 2) is observed as an image moving from approximately the 4 o'clock position at the bottom right of the screen toward the lesion 300 at the center of the screen.

[0050] In other words, the endoscope 10 of the embodiment has a configuration in which the observation window 46 is located in the proximal region 70E, the first treatment instrument outlet 52 is located in the fourth quadrant 70D, the second treatment instrument outlet 54 is located in the third quadrant 70C, and the upper end position 54B of the second treatment instrument outlet 54 in the direction of the vertical axis V is located above the upper end position 52B of the first treatment instrument outlet 52 in the direction of the vertical axis V. As a result, the high-frequency scissors forceps 100 is observed as an image moving from approximately the 6 o'clock position at the bottom of the screen toward the lesion 300 in the center of the screen, and the grasping forceps 200 is observed as an image moving from approximately the 4 o'clock position at the bottom right of the screen toward the lesion 300 in the center of the screen.Therefore, when performing treatment while viewing the lesion 300 on the biological image 400, the high-frequency scissors forceps 100 and the grasping forceps 200 do not get in the way of each other, and it is possible to accurately perform treatment using the high-frequency scissors forceps 100 and the grasping forceps 200 while viewing the lesion 300.

[0051] Moreover, since the endoscope 10 of the embodiment is configured to place the observation window 46 in the adjacent region 70E and the second treatment tool outlet 54 in the third quadrant 70C, when the bending portion 202 of the grasping forceps 200 is bent to lift the lesion portion 300 upward as shown in Fig. 6 and Fig. 7, the bending portion 202 and the pair of grasping portions 204 are observed as images that have moved from the center to the right end side in the living body image 400 in Fig. 8. As a result, the image area of ​​the grasping forceps 200 in the living body image 400 becomes smaller, so that the high-frequency scissors forceps 100 becomes easier to see, and as a result, an incision treatment using the high-frequency scissors forceps 100 can be performed accurately.

[0052] Furthermore, the endoscope 10 of the embodiment is configured to place the observation window 46 in the proximal region 70E and the second treatment tool outlet 54 in the third quadrant 70C, so that when the lesion 300 is lifted by the grasping forceps 200, the pair of grasping parts 204 are located on the right end side of the biological body image 400, and halation (a phenomenon in which an image becomes white) can be suppressed. That is, when a part of the light irradiated from the illumination windows 42, 44 is reflected by the pair of grasping parts 204 and becomes disturbance light and is received by the imaging element from the observation window 46, halation may occur, but since the pair of grasping parts 204 are located on the right end side, the amount of disturbance light received by the imaging element is reduced, and as a result, halation can be suppressed.

[0053] Here, a comparative example to be compared with the endoscope 10 of the embodiment will be briefly described. For example, in the direction of the vertical axis V shown in FIG. 2, when the first treatment tool outlet is arranged in the distal end surface area below the observation window and the second treatment tool outlet is arranged in the distal end surface area above the observation window, the grasping forceps led out from the second treatment tool outlet is observed as an image moving from, for example, the 11 o'clock to 1 o'clock position at the top of the screen toward the center of the screen in the living body image displayed on the display. Therefore, for the surgeon performing treatment while looking at the living body image 400, the grasping forceps may get in the way and make it difficult to see the lesion. And when the lesion is lifted by the grasping forceps, the grasping forceps may be displayed large in the image, so in this case too, the grasping forceps may get in the way and make it difficult to see the lesion. As a result, in the above comparative example, it may be difficult to perform an incision treatment using high-frequency scissors forceps accurately.

[0054] In contrast, the endoscope 10 of the embodiment is configured such that the first treatment tool outlet 52 and the second treatment tool outlet 54 are disposed in a distal end surface region below the observation window 46. Specifically, the observation window 46 is disposed in the proximal region 70E of the first quadrant 70A, the first treatment tool outlet 52 is disposed in the fourth quadrant 70D, the second treatment tool outlet 54 is disposed in the third quadrant 70C, and the upper end position 54B of the second treatment tool outlet 54 is disposed above the upper end position 52B of the first treatment tool outlet 52, so that treatment using the high-frequency scissors forceps 100 and the grasping forceps 200 can be performed accurately.

[0055] In addition, Figures 2 and 3 show a configuration in which the observation window 46, the first treatment tool outlet 52, and the second treatment tool outlet 54 are completely contained in their corresponding corresponding areas (i.e., the proximal area 70E, the fourth quadrant 70D, and the third quadrant 70C), but this configuration is not necessarily limited to this, and it is sufficient that the observation window 46, the first treatment tool outlet 52, and the second treatment tool outlet 54 are mainly disposed in their corresponding corresponding areas.

[0056] Here, the above-mentioned "mainly arranged" refers to a case where the majority (more than half) of the components to be arranged (e.g., observation window 46) is included in the corresponding region (proximal region 70E in the case of observation window 46). In other words, the above-mentioned "mainly arranged" does not necessarily mean a configuration in which the components are completely included in the corresponding region, but also means a configuration in which at least a part of the components is arranged outside the corresponding region as long as the majority of the components are included in the corresponding region. Note that in the following description, the term "mainly arranged" has the same meaning.

[0057] Even when the observation window 46 is disposed mainly in the proximal region 70E, the first treatment tool outlet 52 is disposed mainly in the fourth quadrant 70D, and the second treatment tool outlet 54 is disposed in the third quadrant 70C in this manner, the same effects as those of the above embodiment can be obtained. However, according to the configuration of the above embodiment, the observation window 46, the first treatment tool outlet 52, and the second treatment tool outlet 54 are completely contained in the corresponding corresponding regions (i.e., the proximal region 70E, the fourth quadrant 70D, and the third quadrant 70C), respectively, so that the above-mentioned effects become more prominent.

[0058] Below, the specific arrangement of the observation window 46, the first treatment tool outlet 52, the second treatment tool outlet 54, the forward water supply port 56, the illumination windows 42, 44, and the air and water supply nozzle 58 arranged on the distal end surface 40 in FIG. 2 will be described with reference to FIG.

[0059] First, the observation window 46 is disposed in a central region 70F, which is a region closer to the center C than the outer periphery 40C of the distal end surface 40. Here, if the observation window 46 is disposed in an outer region (not shown), which is a region closer to the outer periphery 40C than the center C of the distal end surface 40, the observation window 46 is too far from the second treatment tool outlet 54, which may affect the treatment by the grasping forceps 200 led out from the second treatment tool outlet 54. In contrast, according to a configuration in which the observation window 46 is disposed in the central region 70F, which is a region closer to the center C than the outer periphery 40C of the distal end surface 40, for example, the high-frequency scissors forceps 100 can be observed as an image directed from the approximately 6 o'clock position at the bottom of the screen toward the lesion 300 in the center of the screen, and the grasping forceps 200 can be observed as an image directed from the approximately 4 o'clock position at the bottom right of the screen toward the lesion 300 in the center of the screen. In other words, the high-frequency scissors forceps 100, which is the main treatment instrument, can be observed from directly below the screen, and the grasping forceps 200, which is the sub treatment instrument, can be observed from the lower right of the screen, making it possible to accurately perform treatments using the high-frequency scissors forceps 100 and the grasping forceps 200.

[0060] On the other hand, the grasping forceps 200 has more functions (bending function) than the high-frequency scissors forceps 100, and therefore has a larger diameter than the high-frequency scissors forceps 100, and therefore the second treatment tool outlet 54 has a larger aperture than the aperture of the first treatment tool outlet 52. And, since the second treatment tool outlet 54 is disposed in the third quadrant 70C, it is possible to reduce the image area occupied by the image of the grasping forceps 200 in the biological body image 400. This makes it even easier to see the high-frequency scissors forceps 100, and therefore it is possible to perform treatment using the high-frequency scissors forceps 100 accurately.

[0061] Further, the observation window 46, the first treatment tool outlet 52, and the second treatment tool outlet 54 are arranged so as to satisfy an arrangement relationship (arrangement relationship A) in which the distance D2 between the center 46A of the observation window 46 and the center 54A of the second treatment tool outlet 54 is longer than the distance D1 between the center 46A of the observation window 46 and the center 52A of the first treatment tool outlet 52. By satisfying this arrangement relationship A, when the bending portion 202 of the grasping forceps 200 is bent and the pair of gripping portions 204 is raised, the bending portion 202 and the pair of gripping portions 204 move to the right end side of the biological body image 400, so that the bending portion 202 and the pair of gripping portions 204 are difficult to see from the biological body image 400. As a result, it is possible to perform the treatment using the high-frequency scissors forceps 100 accurately.

[0062] Further, the observation window 46, the first treatment tool outlet 52, and the second treatment tool outlet 54 are arranged so as to satisfy an arrangement relationship (arrangement relationship B) in which the distance D3 between the center 52A of the first treatment tool outlet 52 and the center 54A of the second treatment tool outlet 54 is longer than the distance D1 between the center 46A of the observation window 46 and the center 52A of the first treatment tool outlet 52. By satisfying this arrangement relationship B, in this case as well, when the pair of gripping parts 204 are raised, the bending part 202 and the pair of gripping parts 204 move to the right end side of the biological body image 400, so that the bending part 202 and the pair of gripping parts 204 are difficult to see from the biological body image 400. As a result, it is possible to perform treatment using the high-frequency scissors forceps 100 accurately.

[0063] In the embodiment of the endoscope 10, as a preferred aspect, the observation window 46, the first treatment tool outlet 52, and the second treatment tool outlet 54 are configured to satisfy both the above-mentioned positional relationship A and positional relationship B, but this is not necessarily limited to this, and they may be configured to satisfy at least one of the above-mentioned positional relationship A and positional relationship B.

[0064] Moreover, the front water supply port 56 is disposed at a position between the observation window 46 and the first treatment tool outlet 52 with respect to the position in the direction of the vertical axis V. Specifically, the position of the center 56A of the front water supply port 56 in the direction of the vertical axis V is disposed between the position of the center 46A of the observation window 46 and the position of the center 52A of the first treatment tool outlet 52 in the direction of the vertical axis V. Furthermore, in such an arrangement, it is preferable that the front water supply port 56 is disposed offset to the outer periphery 40C side of the distal end surface 40 opposite to the center C side of the distal end surface 40 with respect to the line L1 connecting the center 46A of the observation window 46 and the center 52A of the first treatment tool outlet 52. The front water supply port 56 is mainly disposed in the fourth quadrant 70D.

[0065] By satisfying the above-mentioned arrangement positions, in the living body image 400 of Fig. 8, the liquid 60 sprayed from the front water supply port 56 (see Fig. 2) is observed as an image directed from the 7 o'clock to 8 o'clock position at the bottom left of the screen toward the lesion 300 in the center of the screen. That is, in the endoscope 10 of the embodiment, the position of the center 56A in the direction of the vertical axis V of the front water supply port 56 is disposed between the position of the center 46A of the observation window 46 and the position of the center 52A of the first treatment tool outlet 52 in the direction of the vertical axis V, so that when performing treatment while viewing the lesion 300 on the living body image 400, the liquid 60 sprayed toward the lesion 300 can be observed.

[0066] In the endoscope 10 of the embodiment, the front water supply port 56 is completely shifted from the line L1 toward the outer periphery 40C, but the present invention is not limited to this, and it is sufficient that at least the center 56A of the front water supply port 56 is shifted toward the outer periphery 40C. That is, even if the front water supply port 56 is positioned so as to overlap with the line L1, the same effect as that of the embodiment can be obtained. As one specific example of such an arrangement, the example in which the front water supply port 56 is arranged in the fourth quadrant 70D has been shown, but the front water supply port 56 may be arranged in the first quadrant 70A.

[0067] Moreover, the air / water nozzle 58 is disposed in the second quadrant 70B. This allows the empty space in the second quadrant 70B to be effectively utilized as a space for disposing the air / water nozzle 58. As a result, the diameter of the tip 26 can be made small.

[0068] The illumination window 42 and the illumination window 44 are disposed on the outer periphery 40C side of the distal end face 40 opposite to the center C side of the distal end face 40 with respect to the observation window 46. The illumination window 42, the illumination window 44, the observation window 46, the first treatment tool outlet 52 and the second treatment tool outlet 54 are disposed such that a first region T1 surrounded by a straight line L3 connecting the center 46A of the observation window 46 and the centers 42A and 44A of the illumination window 42 and the illumination window 44, respectively, and a second region T2 surrounded by a straight line L4 connecting the center 46A of the observation window 46 and the centers 52A and 54A of the first treatment tool outlet 52 and the second treatment tool outlet 54, respectively, do not overlap with each other.

[0069] By satisfying the above-mentioned positional relationship, when the curved portion 202 of the grasping forceps 200 is curved and the pair of grasping portions 204 is raised, it is possible to prevent the illumination light from the illumination windows 42, 44 from being blocked by the pair of grasping portions 204, and it is also possible to suppress halation caused by the illumination light reflected by the pair of grasping portions 204 entering the observation window 46.

[0070] The distal end surface 40 includes a first surface 41A and a second surface 41B protruding from the first surface 41A toward the distal end of the insertion section 20 (Y(+) direction). The forward water supply port 56 is disposed on the first surface 41A, and the observation window 46 is disposed on the second surface 41B. Here, the first surface 41A corresponds to the first surface of the present invention, and the second surface 41B corresponds to the second surface of the present invention. In this example, the second surface 41B, which is fan-shaped in plan view, is formed in the first quadrant 70A, and the first surface 41A is formed in a part of the first quadrant 70A, the second quadrant 70B, the third quadrant 70C, and the fourth quadrant 70D.

[0071] By arranging the observation window 46 on the second surface 41B and the front water supply port 56 on the first surface 41A, it is possible to suppress halation and the like caused by the remaining water of the liquid 60 that rises in the Y(+) direction from the front water supply port 56. Open The residual water in the liquid 60 in the opening rises in the Y(+) direction due to the effect of surface tension. As a result, there is a concern that the raised residual water may be reflected on the screen, or that the illuminated light may be reflected by the raised residual water, causing halation. In response to this, the endoscope 10 of the embodiment has a configuration in which the observation window 46 is disposed on the second surface 41B and the forward water supply port 56 is disposed on the first surface 41A, so that the reflection of the residual water and halation caused by the above-mentioned raised residual water can be suppressed, and a good image can be displayed.

[0072] In addition, in a configuration in which the observation window 46 is disposed on the second surface 41B and the forward water supply port 56 is disposed on the first surface 41A, the illumination window 42 (first illumination window) is further disposed on the second surface 41B. This makes it possible to prevent residual water in the forward water supply port 56 from adhering to the illumination window 42. As a result, it is possible to prevent a reduction in the amount of illumination light and halation caused by residual water adhering to the illumination window 42.

[0073] The illumination window 44, which corresponds to the second illumination window, is disposed on the first surface 41A. This illumination window 44 is located on the opposite side of the observation window 46 from the side on which the front water supply port 56 is disposed, and is disposed at a position farther away from the front water supply port 56 than the illumination window 42. For this reason, the remaining water in the front water supply port 56 is less likely to adhere to the illumination window 44 than to the illumination window 42, so it is possible to dispose the illumination window 44 on the first surface 41A. It goes without saying that the illumination window 44 may be disposed on the second surface 41B, similar to the illumination window 42.

[0074] Moreover, the illumination window 44 (second illumination window) is offset from the center C of the distal end face 40 toward the outer periphery 40C of the distal end face 40 with respect to a line L2 connecting the center 46A of the observation window 46 and the center 58A of the air / water nozzle 58. The reason why such an arrangement is desirable will be described below.

[0075] The curved portion 202 of the grasping forceps 200 led out from the second treatment tool outlet 54 is curved upward as shown in FIG. 5. At this time, if the illumination window 44 is disposed close to the second treatment tool outlet 54, a part of the light irradiated from the illumination window 44 is reflected by the pair of gripping portions 204, becomes disturbance light, and is received by the image sensor from the observation window 46, which may cause halation. In the endoscope 10 of the embodiment, the illumination window 44 is offset from the second treatment tool outlet 54, so that the disturbance light can be prevented from being received by the image sensor. As a result, halation caused by the grasping forceps 200 led out from the second treatment tool outlet 54 can be prevented, and a good image can be displayed.

[0076] In the embodiment, as a preferred embodiment, the illumination window 44 is arranged so that the illumination window 44 is completely aligned from the line L2 to the outer periphery 40. C However, the present invention is not limited to this, and it is sufficient that at least the center 44A of the illumination window 44 is shifted from the line L2 toward the outer periphery 40C. In other words, even if the illumination window 44 is disposed at a position overlapping the line L2, the same effect as in the embodiment can be achieved.

[0077] In addition, in the above offset arrangement, it is preferable that the illumination window 44 is arranged on the vertical axis V. In this case, even when the bending portion 202 of the grasping forceps 200 is bent, it is possible to prevent the illumination light from the illumination window 44 from being blocked by the pair of grasping portions 204. As a result, a bright and good image can be projected.

[0078] In the embodiment, a preferred embodiment has been described in which the center 44A of the illumination window 44 is disposed at a position overlapping the vertical axis V, but the present invention is not limited thereto, and it is sufficient that at least a portion of the illumination window 44 is disposed on the vertical axis V. In other words, even if a portion of the illumination window 44 is disposed on the vertical axis V, the same effect as in the embodiment can be achieved.

[0079] Hereinafter, several preferred aspects related to the endoscope 10 of the embodiment will be described.

[0080] <Adjusting the installation position of the observation window> First, a case will be described in which the first treatment tool outlet 52 is disposed directly below the observation window 46 in the direction of the vertical axis V. In the observation image, the outlet position of the treatment tool observed in the observation image changes depending on the mounting position of the observation window 46. One example will be described with reference to FIG.

[0081] 9 indicates an observation image 502 when a line (not shown) connecting the center 46A of the observation window 46 (i.e., the center of the observation optical system) and the center 52A of the first treatment tool outlet 52 (see FIG. 2) is inclined at an angle of 1 degree or less to the right with respect to a line parallel to the vertical axis V when the distal end surface 40 is viewed from the Y(+) direction. Reference symbol IXB indicates an observation image 504 when a line connecting the center 46A of the observation window 46 and the center 52A of the first treatment tool outlet 52 is inclined at an angle of 10 degrees to the right with respect to a line parallel to the vertical axis V when the distal end surface 40 is viewed from the Y(+) direction. Reference symbol IXC indicates an observation image 506 when a line connecting the center 46A of the observation window 46 and the center 52A of the first treatment tool outlet 52 is inclined at an angle of 7 degrees to the left with respect to a line parallel to the vertical axis V when the distal end surface 40 is viewed from the Y(+) direction. In this example, for ease of explanation, a form will be described in which the center 46A of the observation window 46 and the center of the observation optical system are pre-aligned on the same straight line. However, if the center 46A of the observation window 46 and the center of the observation optical system are not aligned, the position of the center of the observation optical system will be adjusted.

[0082] In the observed image 502, the high-frequency scissors forceps 100 is observed as being derived from directly below (the 6 o'clock position) the observed image 502 toward the center of the observed image 502. In contrast, in the observed image 504, the high-frequency scissors forceps 100 is observed as being derived from the lower left of the observed image 504, and in the observed image 506, the high-frequency scissors forceps 100 is observed as being derived from the lower right of the observed image 506.

[0083] In this way, the high-frequency scissors forceps 100 appears to be drawn out from a different position in the observation image depending on the mounting position of the observation window 46. This may affect the procedure of the surgeon.

[0084] In order to solve this problem, the attachment position of the observation window 46 is adjusted so that the inclination of the line connecting the center 46A of the observation window 46 and the center 52A of the first treatment tool outlet 52 is within 3 degrees with respect to the vertical axis V, so that the outlet position of the high-frequency scissors forceps 100 appears constant in the observation image. This enables the surgeon to perform treatment with stable technique.

[0085] The mounting position of the observation window 46 can be adjusted by using an adjustment jig to adjust the position of the observation window 46 while viewing an image captured by the observation optical system.

[0086] <About the bending mechanism> Next, in order to bend the bending portion 24 of the configuration of the handheld operation unit 18, of An example of a bending operation mechanism will be described. Fig. 10 is a schematic cross-sectional view of the handheld operation unit 18, and a part of the bending portion 24 is also shown as a cross-sectional view in the same figure. Fig. 10 shows, among the bending operation mechanisms that bend the bending portion 24, a bending operation mechanism that bends the bending portion 24 in the up-down direction, and a bending operation mechanism that bends the bending portion 24 in the left-right direction is omitted because it is the same mechanism. The former bending operation mechanism will be described below, and the latter bending operation mechanism will be omitted.

[0087] As shown in FIG. 10, the bending portion 24, as an example, has a plurality of substantially cylindrical bending pieces 552 and a plurality of rivet pins 554 that connect adjacent bending pieces 552 to each other, and the adjacent bending pieces 552 are connected to each other so as to be rotatable around the rivet pins 554 as axes.

[0088] 13 to 15, in addition to built-in components such as a first treatment tool channel 714, a second treatment tool channel 716, a liquid feed tube 708, a liquid supply tube 710, a gas supply tube 712, a signal cable 702, and light guides 704 and 706, a pair of angle wires 556 for bending the bending portion 24 up and down and a pair of angle wires 556 for bending the bending portion 24 left and right are inserted into the flexible portion 22 and the bending portion 24. The two pairs of angle wires 556 are each disposed along the direction of the long axis Ax of the insertion portion 20, and are engaged with the bending piece 552 by being inserted into holes 720 of pins 722a, 722b, 722c, and 722d provided inside the rivet pin 554 of the bending portion 24.

[0089] Of the two pairs of angle wires 556, the distal end portions of the pair of angle wires 556 for vertical operation are fixed to the distal end portion 26, and the proximal end portions of the pair of angle wires 556 are joined to a pair of sleeves 557 for vertical operation shown in Fig. 10. As a result, the bending portion 24 is bent in the vertical direction by pushing and pulling the pair of angle wires 556 via the pair of sleeves 557.

[0090] A bending operation mechanism 558 for vertical operation provided inside the handheld operation unit 18 has a sprocket 560 and a chain 562 wound around the sprocket 560. A pair of sleeves 557 are joined to both ends of the chain 562.

[0091] The sprocket 560 is connected to the angle knob 28 (see FIG. 1) for vertical operation via a rotating shaft 560A, and is rotated in conjunction with the rotation of the angle knob 28. This causes the pair of angle wires 556 to be pushed and pulled via the chain 562 and the pair of sleeves 557. That is, one of the pair of angle wires 556 is pulled toward the base end, and the other is sent out toward the tip end.

[0092] Here, stoppers 564A and 564B are provided on the base end side of the sleeves 557, 557 to restrict movement of the sleeves 557, 557 toward the base end side by abutting against the sleeves 557, 557. The positions of the stoppers 564A and 564B are adjustable, respectively, and the movement of the sleeves 557, 557 is restricted by the stoppers 564A and 564B. As a result, the maximum bending angle of the bending portion 24 in the up-down direction is regulated.

[0093] Further, stoppers 564A, 564B are set such that stopper 564A restricting the Up side (Z(+) direction side) is located closer to the base end than stopper 564B restricting the Down side (Z(-) direction side). This allows bending section 24 to bend at a larger angle toward the Up side than toward the Down side. As a result, when bending section 24 is bent toward the Up side, it becomes possible to observe the body wall on the opposite side to the insertion direction of insertion section 20. Note that in this case, the bending angle toward the Down side is smaller (for example, the Up side is 210 degrees while the Down side is 90 degrees), but since the Up side is mainly used in the endoscope, there is no problem in using the endoscope.

[0094] On the other hand, in an endoscope (for example, an endoscope using two treatment tools simultaneously) that requires a large traction force (large torque) when bending the bending portion 24, even if the angle knob 28 is operated, the angle wire 556 may stretch and not contribute to the bending operation of the bending portion 24. In order to prevent this problem, the position of the stopper 564A that restricts the Up side is disposed further toward the base end side. As a result, the angle wire 556 can be pulled including the amount of stretch of the angle wire 556, so that even an endoscope with a large torque can be bent to the Up side. In this way, by adjusting the positions of the stoppers 564A and 564B according to the magnitude of the torque, common parts can be used without using dedicated parts according to the magnitude of the torque.

[0095] <About the curved section> Next, an example of the configuration of the bending portion 24 will be described. Fig. 11 is a diagram (graph) showing the relationship between the torque (traction force) generated when bending the bending portion 24 and the bending angle of the bending portion 24. Fig. 12 is a diagram showing a connection form of a plurality of bending pieces 552 that constitute the bending portion 24.

[0096] In an endoscope having the torque fluctuation shown by line LA in Fig. 11 (herein referred to as endoscope A), the bending portion 24 can be bent with a gradually increasing torque up to a certain angle, but when a certain bending angle (190 degrees on line LA) is exceeded, there is an inflection point where a larger torque is required. Therefore, in this endoscope A, the bending portion 24 can be bent without any problems up to a bending angle of 190 degrees, but when the bending angle exceeds 190 degrees, a larger torque is required, which places a burden on the surgeon, and even if the angle wire 556 is pulled with a large torque, the angle wire 556 stretches, so that it may not be possible to obtain a predetermined bending angle for the traction force.

[0097] It should be noted that line LA was measured when the bending section contained internal objects, but this tendency was the same when no internal objects were present. When the torque and bending angle of endoscope A was measured using the bending section alone, without any internal objects, it was confirmed that there was an inflection point at 225 degrees.

[0098] Therefore, the above problem was solved by configuring the bending portion 24 as follows, so that the angle of the inflection point when no built-in object is contained within the bending portion 24 is made larger than the above 225 degrees. The configuration of the bending portion 24 will be described below.

[0099] That is, as shown in Fig. 12, the bending pieces 552 constituting the bending portion 24 have a pair of tongue-shaped connecting pieces 602 protruding in the Y-axis direction in the circumferential direction. The pair of connecting pieces 602 are arranged at intervals of 180 degrees in the circumferential direction of the bending piece 552. The connecting pieces 602 of adjacent bending pieces 552 are overlapped with each other, and a rivet pin 606 is attached to a through hole 604 formed in the connecting piece 602 to connect the adjacent bending pieces 552. As a result, the multiple bending pieces 552 are connected to be rotatable in the up-down direction via the two rivet pins 606, 606 arranged in the left-right direction.

[0100] In order to bend the bending portion 24 at a larger bending angle than the conventional one, for example, the following can be done. That is, the inclination angle of the end 608 with respect to the Z axis is increased so that the end portions 608, 608 of adjacent bending pieces 552 facing each other in the Y axis direction move away from each other in the Y axis direction. This makes the bending angle of the bending portion 24 larger than the conventional one when the bending portion 24 is bent. As a result, it becomes possible to set the inflection point of the bending portion 24 alone to, for example, 225 degrees or more, and it becomes possible to set the inflection point of the bending portion 24 including the built-in object to, for example, 205 degrees or more (see endoscope B indicated by line LB in FIG. 11).

[0101] It is preferable that the bending pieces for increasing the inclination angle of the end 608 are those in the middle portion of the multiple bending pieces 552 connected in the Y-axis direction, excluding the bending piece 552 on the tip side connected to the tip portion 26 and the bending piece 552 on the base side connected to the flexible section 22.

[0102] That is, the position of the bending piece 552 on the tip side in the Y-axis direction is the position where the tube, which is the outer skin of the bending portion 24, is fixed to the tip portion 26, and is a part with high rigidity due to hardening of the adhesive. Therefore, when the inclination angle of the end portion 608 is increased in the bending piece 552 on the tip side, a large torque is required to bend this part (the part with high rigidity), so it is preferable to use the conventional bending piece 552 on the tip side.

[0103] Furthermore, the position of the bending piece 552 on the base end side in the Y-axis direction is the position that is the starting point for bending the bending portion 24. Therefore, when the inclination angle of the end portion 608 of the bending piece 552 on the base end side is increased, the tip portion 26 of the endoscope 10 rises up high at the position of the bending piece 552. Therefore, the curvature of the bending portion 24 when bent becomes small, and as a result, it becomes difficult to invert the bending portion 24 with a large curvature. In other words, since the observation range of the endoscope 10 becomes narrower, it is preferable that the bending piece 552 on the base end side be the same as before.

[0104] <About the internal structure of the curved section> Next, a preferred internal structure of the bending section 24 will be described. As described above, the distal end surface 40 of the endoscope 10 is provided with the illumination windows 42, 44, the observation window 46, the first treatment tool outlet 52, the second treatment tool outlet 54, the air / water supply nozzle 58, and the front water supply port 56. These are connected to the handheld operation section 18 via various cables and various channels (hereinafter referred to as built-in components) inserted inside the bending section 24 and the flexible section 22.

[0105] The illumination windows 42, 44, the observation window 46, the first treatment tool outlet 52, the second treatment tool outlet 54, the air and water supply nozzle 58, and the forward water supply port 56 are fixed to the tip portion 26, but since the curved portion 24 is curved, it is preferable that the internal components within the curved portion 24 are arranged without being fixed.

[0106] However, when the bending operation of the bending portion 24 is repeated, the internal objects may move within the bending portion 24. In this case, problems may occur such as the internal objects kinking (twisting or twisting), the cable breaking, and the arrangement within the bending portion becoming distorted relative to the arrangement of the tip surface.

[0107] Therefore, in order to prevent the arrangement of the built-in items in the bending portion 24 from becoming disarrayed, it is preferable to provide the following configuration.

[0108] (1) The outer diameters of the first treatment tool channel 714 and the second treatment tool channel 716 are increased.

[0109] FIG. 13 is a cross-sectional view showing the internal structure of the bending portion, viewed from the Y(-) direction to the Y(+) direction. When the bending portion 24 is divided in half in the Z-axis direction in accordance with the arrangement of each component of the distal end surface 40, the signal cable 702, the light guides 704 and 706, the liquid supply tube 708 that supplies water to the front water supply port 56, the liquid supply tube 710 that supplies liquid to the air and water supply nozzle 58, and the gas supply tube 712 that supplies gas are arranged in the Z(+) direction side region of the two divided regions. In addition, the first treatment tool channel 714 and the second treatment tool channel 716 are arranged in the Z(-) direction side region. In addition, the bending portion 24 has pins 722a, 722b, 722c, and 722d having holes 720 through which the angle wire 556 for bending the bending portion 24 passes in the up, down, left, and right directions of the inner circumference.

[0110] In the curved portion 24 shown in FIG. 13, the outer diameters of the first treatment instrument channel 714 and the second treatment instrument channel 716 are each made larger, and the distance between the pins 722b, 722d facing each other in the X-axis direction is made shorter than the sum of the outer diameters of the first treatment instrument channel 714 and the second treatment instrument channel 716.

[0111] Furthermore, it is preferable that the first treatment instrument channel 714 has an outer diameter that does not move into the Z(+) direction area by abutting the X(-) side pin 722d and the second treatment instrument channel 716, and the second treatment instrument channel 716 has an outer diameter that does not move into the Z(+) direction area by abutting the X(+) side pin 722b and the first treatment instrument channel 714.

[0112] With the above configuration, it is possible to prevent both the first treatment tool channel 714 and the second treatment tool channel 716 from moving to the area on the Z(+) direction side. In addition, the first treatment tool channel 714 and the second treatment tool channel 716 can prevent the signal cable 702, the light guides 704, 706, the liquid delivery tube 708, the liquid supply tube 710, and the gas supply tube 712 from moving to the area on the Z(-) direction side. As a result, it is possible to prevent the arrangement of the built-in items in the bending section 24 from being disturbed.

[0113] (2) The pin extends toward the center.

[0114] Fig. 14 is a diagram for explaining another embodiment for preventing the above-mentioned disorder of the arrangement. In the embodiment shown in Fig. 14, pins 722b and 722d provided opposite to each other in the X-axis direction are extended toward the center of the bending portion 24. The distance between the pins 722b and 722d facing each other is set shorter than the outer diameter of the first treatment tool channel 714 and the outer diameter of the second treatment tool channel 716.

[0115] This makes it possible to prevent the first treatment tool channel 714 and the second treatment tool channel 716 from moving to the area on the Z(+) direction side of the pins 722d, 722b provided in the X-axis direction. As a result, it is possible to prevent the arrangement in the bending portion 24 from being disturbed.

[0116] Furthermore, by configuring the pins 722b, 722d of each bending piece 552 of the bending portion 24 in the above-described shape, the force applied to the pins 722b, 722d can be dispersed, and damage to the pins 722b, 722d can be prevented.

[0117] (3) A partition member is provided within the curved portion.

[0118] Fig. 15 is a diagram for explaining yet another embodiment for preventing the above-mentioned disturbance of the arrangement. In the embodiment shown in Fig. 15, a partition member 724 is provided in the area on the Z(+) direction side. The partition member 724 is a component housed in the area on the Z(+) direction side, and is provided to surround the signal cable 702, the light guides 704, 706, the liquid delivery tube 708, the liquid supply tube 710, and the gas supply tube 712.

[0119] This prevents the various cables and channels from being swapped between the areas on the Z(+) direction and the Z(-) direction, thereby preventing the arrangement of the internal components from becoming distorted.

[0120] The partition member 724 can be provided at any position within the curved portion 24. The partition member 724 can be fixed by spot welding, or by inserting it into the curved portion after the curved portion is assembled.

[0121] Although the endoscope according to the embodiment has been described above, the present invention may be improved or modified in several ways without departing from the gist of the present invention. [Explanation of symbols]

[0122] 10 Endoscopy 12 Endoscope System 14. Processor device for endoscope 16 Display 18 Handheld operation unit 20 Insertion section 22 Soft part 24 Curved section 26 Tip 28 Angle knob 30 Angle knob 31A Air / Water Supply Button 31B Suction button 32 Universal Cable 34 Connector device 35 Water Supply Connector 36 Light source device 37 Processor side connector 38 Image Processing Device 40 Tip surface 40C outer circumference 40D top end 41A 1st page 41B 2nd side 42 Lighting window 42A center 44 Lighting window 44A center 46 Observation window 46A center 48 First treatment tool inlet 50 Second treatment tool introduction port 52 First treatment tool outlet 52A center 52B Top position 54 Second treatment tool outlet 54A center 54B Top position 56 Front water inlet 56A center 58 Air and water supply nozzle 58A center 60 liquid 70A 1st quadrant 70B 2nd quadrant 70C 3rd quadrant 70D Quadrant 4 70E Close Range 70F Center side area 100 High Frequency Scissors and Forceps 102 Nails 200 Grasping forceps 202 Curved section 204 Gripping part 300 Lesions 400 Biometric Images 502 Observation images 504 Observation images 506 Observation Images 552 Curved piece 554 Rivet pin 556 Angle Wire 557 Sleeve 558 Curvature Operation Mechanism 560 Sprocket 560A Rotating Shaft 562 Chain 564A Stopper 564B Stopper 602 Connecting piece 604 Through hole 606 Rivet Pin 608 End 702 Signal Cable 704 Light Guide 706 Light Guide 708 Liquid delivery pipe 710 Liquid supply pipe 712 Gas supply pipe 714 1st treatment tool channel 716 Second treatment tool channel 720 holes 722a Pin 722b Pin 722c Pin 722d Pin 724 Partition material Ax long axis C center H horizontal axis V vertical axis L1 line L2 line L3 line L4 line D1 Distance D2 distance D3 distance T1 First area T2 Second area

Claims

1. an observation window for observing the inside of a subject, the observation window being disposed on a distal end surface of the insertion portion which is bendable in the vertical and horizontal directions; a first treatment tool outlet provided on the distal end surface and capable of outletting a first treatment tool; a second treatment tool outlet provided on the distal end surface and capable of outletting a second treatment tool; Equipped with When the tip surface is viewed from the front, of two axes that pass through the center of the tip surface and are perpendicular to each other, an axis parallel to the left-right direction is defined as a first axis, an axis parallel to the up-down direction is defined as a second axis, a direction of the first axis is a direction along the horizontal direction of an image based on an electrical signal from an imaging element that receives light incident from the observation window, and a direction of the second axis is a direction along the up-down direction of the image, and among the divided regions obtained by dividing the tip surface into four by the first axis and the second axis, the upper right divided region is defined as a first quadrant, the upper left divided region is defined as a second quadrant, the lower left divided region is defined as a third quadrant, and the lower right divided region is defined as a fourth quadrant, The observation window is disposed mainly in a proximal region of the first quadrant that is proximal to the first axis, The first treatment tool outlet is mainly disposed in the fourth quadrant, The second treatment tool outlet is mainly disposed in the third quadrant, an upper end position of the second treatment tool outlet in the second axial direction is disposed higher than an upper end position of the first treatment tool outlet in the second axial direction; Endoscope.

2. The observation window is mainly disposed in a central region, which is a region closer to the center than the outer periphery of the tip surface. The endoscope according to claim 1 .

3. The second treatment tool outlet has a larger diameter than the first treatment tool outlet.

3. An endoscope according to claim 1 or 2.

4. a distance between a center of the observation window and a center of the second treatment tool outlet is longer than a distance between a center of the observation window and a center of the first treatment tool outlet; The endoscope according to any one of claims 1 to 3.

5. a distance between a center of the first treatment tool outlet and a center of the second treatment tool outlet is longer than a distance between a center of the observation window and a center of the first treatment tool outlet; The endoscope according to any one of claims 1 to 4.

6. a forward water supply port for injecting a liquid toward a site to be observed in the subject is provided on the distal end surface; A center position of the front water supply port in the second axial direction is disposed between a center position of the observation window and a center position of the first treatment tool outlet in the second axial direction. The endoscope according to any one of claims 1 to 5.

7. The front water supply port is offset to the outer periphery of the distal end surface on the opposite side to the center of the distal end surface with respect to a line connecting the center of the observation window and the center of the first treatment tool outlet. The endoscope according to claim 6.

8. The front water inlet is disposed primarily in the fourth quadrant. The endoscope according to claim 7.

9. The second quadrant has an air / water supply nozzle.

9. An endoscope according to any one of claims 1 to 8.

10. The tip surface has a first illumination window and a second illumination window, the first illumination window and the second illumination window are disposed on an outer circumferential side of the tip surface opposite to a center side of the tip surface with respect to the observation window, a first region surrounded by straight lines connecting a center of the observation window and a center of each of the first illumination window and the second illumination window, and a second region surrounded by straight lines connecting the center of the observation window and a center of each of the first treatment tool outlet and the second treatment tool outlet do not overlap with each other; 10. An endoscope according to any one of claims 1 to 9.

11. a forward water supply port for injecting a liquid toward a site to be observed in the subject is provided on the distal end surface; The tip surface includes a first surface and a second surface protruding from the first surface toward the tip of the insertion portion, The front water supply port is disposed on the first surface, The observation window is disposed on the second surface. The endoscope according to claim 10.

12. The first illumination window is disposed on the second surface. The endoscope according to claim 11.

13. An air / water supply nozzle is provided in the second quadrant, the second illumination window is offset from a line connecting a center of the observation window and a center of the air / water nozzle to an outer periphery of the tip surface opposite to a center of the tip surface, An endoscope according to any one of claims 10 to 12.

14. The second illumination window is disposed on the second axis. The endoscope according to claim 13.

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