Endoscope

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 tip face region 40A above a horizontal axis H, and a first treatment instrument lead-out port 52 is principally disposed in a tip face region 40B below the horizontal axis H. The position of a center 56A in a direction of a vertical axis V of a front water supply port 56 is disposed between the position of a center 46A of the observation window 46 in the direction of the vertical axis V and the position of a center 52A 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 at the distal end of an insertion portion.

Background Art

[0002] In an endoscope, various treatment tools are introduced from a treatment tool inlet provided in an operation portion, and the treatment tools are led out to the outside from a treatment tool outlet opened at the distal end of an insertion portion, thereby performing various treatments on a subject. As an example of such a treatment, endoscopic submucosal dissection (ESD) is known.

[0003] Patent Document 1 discloses an endoscope that performs a treatment by leading out different treatment tools from two treatment tool outlets opened at the distal end of an insertion portion.

[0004] The endoscope of Patent Document 1 has, as two treatment tool outlets, a cutting treatment tool outlet for protruding a cutting treatment tool for cutting body tissue and a capturing treatment tool outlet for protruding a capturing treatment tool for capturing the cut tissue. Further, the cutting treatment tool outlet and the capturing treatment tool outlet are arranged to open at positions sandwiching an observation window in a diagonal direction of a visual field mask. Also, a washing water jet outlet for jetting washing water is arranged 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 washing water jet outlet jets washing water in a direction substantially parallel to the treatment tool protruding direction from the cutting treatment tool outlet.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the endoscope of Patent Document 1, in the image of the subject obtained through the observation window, the capture treatment tool protruding from the capture treatment tool outlet is observed as an image that appears from above the screen and heads towards the center of the screen. Therefore, from the perspective of the operator performing the treatment while looking at the image, the capture treatment tool may get in the way and make it difficult to see the lesion, and as a result, it may be difficult to accurately perform the treatment with the treatment tool.

[0007] The present invention has been made in view of such circumstances, and provides an endoscope capable of accurately performing a treatment with a treatment tool.

Means for Solving the Problems

[0008] To achieve the object of the present invention, the endoscope according to the present invention is disposed on the tip surface of an insertion portion that can be bent in the vertical and horizontal directions, and includes an observation window for observing the inside of the subject, and is disposed on the tip surface. A first treatment tool outlet through which a first treatment tool can be led out, and a front water supply port disposed on the tip surface for injecting a liquid toward an observation site inside the subject. When looking at the tip surface from the front, among the two axes passing through the center of the tip surface and perpendicular to each other, the axis parallel to the horizontal direction is defined as the first axis, and the axis parallel to the vertical direction is defined as the second axis. The observation window is mainly disposed in the tip surface region above the first axis, the first treatment tool outlet is mainly disposed in the tip surface region below the first axis, and the central position of the front water supply port in the direction of the second axis is disposed between the central position of the observation window and the central position of the first treatment tool outlet in the direction of the second axis.

[0009] In one form of the present invention, among the divided regions obtained by dividing the tip surface by the first axis and the second axis, when the upper right divided region is defined as the first quadrant, the upper left divided region is defined as the second quadrant, the lower left divided region is defined as the third quadrant, and the lower right divided region is defined as the fourth quadrant, the observation window is preferably mainly disposed in the first quadrant, and the first treatment tool outlet is preferably mainly disposed in the fourth quadrant or the third quadrant.

[0010] In one aspect of the present invention, the front water inlet is preferably offset and arranged on the outer peripheral side of the tip surface on the side opposite to the center side of the tip surface with respect to the line connecting the center of the observation window and the center of the first treatment tool outlet.

[0011] In one aspect of the present invention, the front water inlet is preferably mainly arranged in the fourth quadrant.

[0012] In one aspect of the present invention, the tip surface has a second treatment tool outlet through which the second treatment tool can be led out. The first treatment tool outlet is preferably mainly arranged in the fourth quadrant, and the second treatment tool outlet is preferably mainly arranged in the third quadrant.

[0013] In one aspect of the present invention, the second treatment tool outlet preferably has a larger diameter than the diameter of the first treatment tool outlet.

[0014] In one aspect of the present invention, the tip surface includes a first surface and a second surface protruding from the first surface in the tip direction of the insertion portion. The front water inlet is preferably arranged on the first surface, and the observation window is preferably arranged on the second surface.

[0015] In one aspect of the present invention, it is preferable to have a first illumination window on the second surface.

[0016] In one aspect of the present invention, when the tip surface is divided into four divided regions by the first axis and the second axis, 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, it is preferable to have an air and water supply nozzle in the second quadrant.

[0017] In one aspect of the present invention, the tip surface has a second illumination window, and the second illumination window is preferably offset and arranged on the outer peripheral side of the tip surface on the side opposite to the center side of the tip surface with respect to the line connecting the center of the observation window and the center of the air and water supply nozzle.

[0018] In one aspect of the present invention, the second illumination window is preferably arranged on the second axis.

Advantages of the Invention

[0019] According to the present invention, it becomes possible to accurately perform a treatment with a treatment instrument.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Mode for Carrying Out the Invention

[0021] Hereinafter, embodiments of the endoscope of the present invention will be described with reference to the accompanying drawings.

[0022] FIG. 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 an endoscope 10, an endoscope processor device 14, and a display 16.

[0023] The endoscope 10 includes a hand operation unit 18 and an insertion unit 20 provided at the distal end side of the hand operation unit 18 and inserted into a subject.

[0024] The insertion unit 20 has a long axis Ax extending from the proximal end portion to the distal end portion, and includes a flexible portion 22, a bending portion 24, and a distal end portion 26 in order from the proximal end side to the distal end side.

[0025] A pair of angle knobs 28 and 30 for bending the bending portion 24 are arranged on the hand operation unit 18. The pair of angle knobs 28 and 30 are provided rotatably coaxially. The angle knobs 28 and 30 and the bending portion 24 are connected by four angle wires (not shown) inserted through the flexible portion 22. By rotating the angle knobs 28 and 30, these angle wires are pushed and pulled to bend the bending portion 24 in the vertical direction and the horizontal direction. Further, the hand operation unit 18 is provided with an air / water supply button 31A and a suction button 31B.

[0026] In this specification, the description will be given using a three-dimensional orthogonal coordinate system with three mutually orthogonal axes (X-axis direction, Y-axis direction, Z-axis direction). That is, when looking at the distal end portion 26 from the hand operation unit 18, if the direction in which the bending portion 24 faces when the angle knob 28 for vertical direction operation is rotated in the UP direction is defined as the upward direction, the upward direction is defined as the Z(+) direction, and the downward direction, which is the opposite direction, is defined as the Z(-) direction. Also, if the direction in which the bending portion 24 faces when the angle knob 30 for left-right direction operation is rotated in the R direction is defined as the right direction, the right direction is defined as the X(+) direction, and the left direction is defined as the X(-) direction. Further, the front direction (the direction on the distal end side in the major axis Ax direction) at that time is defined as the Y(+) direction, and the rear direction (the direction on the proximal end side in the major axis Ax direction) is defined as the Y(-) direction. Note that the Y-axis direction including the Y(+) direction and the Y(-) direction is parallel to the direction of the major axis Ax.

[0027] The base end portion of the universal cable 32 is connected to the hand operation unit 18, and a connector device 34 is provided at the tip end portion of the universal cable 32. The connector device 34 is connected to the endoscope processor device 14.

[0028] The endoscope processor device 14 includes a light source device 36 and an image processing device 38. The light source device 36 is provided with a processor-side connector 37 to which the connector device 34 is connected. Further, a display 16 for displaying an image processed by the image processing device 38 is connected to the image processing device 38. According to this endoscope system 12, the light from the light source device 36 is transmitted through an optical fiber cable (not shown) and irradiated forward (in the Y(+) direction) from the illumination windows 42 and 44 provided on the front end surface 40 (see FIG. 2) of the distal end portion 26. Further, the image light incident from the observation window 46 provided on the front end surface 40 (see FIG. 2) is received by an imaging element (not shown) through an observation optical system (not shown) provided, for example, behind the observation window 46 (in the Y(-) direction). Then, the electrical signal photoelectrically converted by the imaging element is processed by the image processing device 38 and projected as an image of the subject inside the body (hereinafter, also referred to as a "biological image") on the screen of the display 16. In the display 16, the vertical direction in which the curved portion 24 curves is aligned with the vertical direction in the screen, and the horizontal direction in which the curved portion 24 curves is aligned with the horizontal direction in the screen.

[0029] Further, the hand operation unit 18 in FIG. 1 is provided with a first treatment tool introduction port 48 into which a first treatment tool can be introduced and a second treatment tool introduction port 50 into which a second treatment tool can be introduced. Further, a first treatment tool channel (not shown) and a second treatment tool channel are inserted through the insertion portion 20. The base end portion of the first treatment tool channel is connected to the first treatment tool introduction port 48, and the distal end portion thereof is connected to a first treatment tool outlet 52 opened at the front end surface 40 shown in FIG. 2. The base end portion of the second treatment tool channel is connected to the second treatment tool introduction port 50 shown in FIG. 1, and the distal end portion thereof is connected to a second treatment tool outlet 54 opened at the front end surface 40 of FIG. 2. As an example of the first treatment tool, a cutting treatment tool (for example, high-frequency scissors forceps, an ESD knife, biopsy forceps) for cutting (incising) body tissue is used. Further, 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, or an endoscope stapler having a suturing function. The above is an overview of the endoscope 10.

[0030] Here, in a forward-view endoscope such as the endoscope 10 in this example, in which an observation window 46, treatment tool outlets (in this example, a first treatment tool outlet 52 and a second treatment tool outlet 54) are provided at the distal end portion 26 of the insertion portion 20, the following points are required in order to enable accurate treatment with a treatment tool.

[0031] That is, an operator who operates the endoscope 10 inserts a treatment tool from the treatment tool outlet while viewing a biological image projected on the display 16 to perform treatment on a lesion. For this reason, it is necessary to avoid the situation where the treatment tool obstructs the view and makes it difficult to see the lesion in the biological image. Therefore, the endoscope 10 in this example enables accurate treatment with a treatment tool by providing components such as the observation window 46, the first treatment tool outlet 52, and the second treatment tool outlet 54 provided on the front end surface 40 of the distal end portion 26 shown in FIG. 2 at suitable arrangement positions shown in FIG. 2. Hereinafter, an example of a suitable arrangement position of the above components will be described in detail.

[0032] FIG. 2 is a front view of the distal end portion 26. That is, FIG. 2 is a view of the front end surface 40 of the distal end portion 26 seen from the Y(+) side toward the Y(-) side.

[0033] As shown in FIG. 2, on the front end surface 40 of the distal end portion 26, a lighting window 42, 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 / water supply nozzle 58 are provided at respective predetermined arrangement positions. Here, the lighting window 42 corresponds to the first lighting window of the present invention, and the lighting window 44 corresponds to the second lighting 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. Further, the front water supply port 56 corresponds to the front water supply port of the present invention, and the air / water supply nozzle 58 corresponds to the air / water supply nozzle of the present invention.

[0034] The observation window 46 is a window for observing the subject located in front (in the Y(+) direction) of the distal end portion 26 as described above, and the illumination windows 42 and 44 are arranged so as to sandwich the observation window 46. Here, for example, when the diameter of the distal end portion 26 is 12.5 to 13.0 mm, the observation window 46 and the illumination windows 42 and 44 are each formed to have a diameter of about 1.5 to 2.0 mm as an example.

[0035] The first treatment instrument outlet 52 is an opening through which the above-described cutting treatment instrument (first treatment instrument) can be led forward. The second treatment instrument outlet 54 is an opening through which, for example, the above-described grasping forceps (second treatment instrument) can be led forward. The second treatment instrument outlet 54 is formed to have a diameter of about 3.5 to 4.0 mm as an example in order to allow the grasping forceps having a larger diameter than the cutting treatment instrument to pass through. That is, the diameter of the second treatment instrument outlet 54 is formed to be larger than the diameter of the first treatment instrument outlet 52 (about 3.0 to 3.5 mm as an example) through which the cutting treatment instrument only needs to pass. Note that the first treatment instrument outlet 52 also functions as a suction port for sucking liquid or the like in the subject by operating the suction button 31B in FIG. 1.

[0036] The forward water supply port 56 is an opening for injecting liquid toward the observed site (for example, a lesion) in the subject, and is formed to have a diameter of about 1.0 to 1.5 mm as an example. The forward 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 by driving the water supply device, liquid is supplied to the forward water supply port 56 via the water supply tube.

[0037] The air and water injection nozzle 58 is a nozzle for injecting liquid and air mainly toward the observation window 46. Liquid or air is selectively supplied to the air and water injection nozzle 58 by operating the air and water injection button 31A shown in FIG. 1.

[0038] Here, as shown in FIG. 2, when the tip surface 40 is viewed from the front, of the two axes passing through the center C of the tip surface 40 and perpendicular to each other, the axis parallel to the left - right direction is defined as the horizontal axis H, and the axis parallel to the up - down direction is defined as the vertical axis V. In this case, the observation window 46 is disposed in the tip surface region 40A above the horizontal axis H, and the first treatment tool outlet 52 is disposed in the tip surface region 40B below the horizontal axis H. And at the front water inlet 56, the position of the center 56A in the direction of the vertical axis V of the front water inlet 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. 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.

[0039] Next, an example of a treatment method using the endoscope 10 of the embodiment will be described with reference to FIGS. 3 to 6. FIGS. 3 to 6 show the procedure of the treatment method in ESD. Also, as the first treatment tool, as shown in FIG. 6, a high - frequency forceps 100 having a pair of claws 102 that can be opened and closed at the tip is used. The pair of claws 102 are opened and closed by an operation part (not shown) of the high - frequency forceps 100. When the pair of claws 102 are closed and the biological tissue is held by the pair of claws 102, by passing a high - frequency current between the pair of claws 102, the biological tissue is cauterized and incised.

[0040] Also, as the second treatment tool, as shown in FIG. 3, a grasping forceps 200 having a bending part 202 and a pair of grasping parts 204 at the tip is used. The bending part 202 is bent by an operation part (not shown) of the grasping forceps 200, and the pair of grasping parts 204 are opened and closed by the above - mentioned operation part.

[0041] First, the insertion portion 20 of the endoscope 10 shown in FIG. 1 is inserted orally into the subject's body. Then, as shown in FIG. 3, when the distal end portion 26 is positioned on the side of the lesion portion 300 of the mucosal layer, the high-frequency scissors forceps 100 (see FIG. 6) are inserted into the first treatment tool channel from the first treatment tool inlet 48 of the endoscope 10 (see FIG. 1). Then, the grasping forceps 200 (see FIG. 3) are inserted into the second treatment tool channel from the second treatment tool inlet 50, and as shown in FIG. 3, the pair of grasping portions 204 and the bending portion 202 of the grasping forceps 200 are led forward from the second treatment tool outlet 54. Then, as shown in FIGS. 3 and 4, the operation portion (not shown) of the grasping forceps 200 is operated to grasp the lesion portion 300 with the pair of grasping portions 204.

[0042] Next, as shown in FIG. 5, the operation portion (not shown) of the grasping forceps 200 is operated to bend the bending portion 202 upward (in the Z(+) direction). As a result, the pair of grasping portions 204 are lifted, and the lesion portion 300 grasped by the pair of grasping portions 204 is lifted upward.

[0043] Next, as shown in FIG. 5, in a state where the lesion portion 300 is lifted, as shown in FIG. 6, the high-frequency scissors forceps 100 inserted into the first treatment tool channel are led forward from the first treatment tool outlet 52. Then, the pair of claws 102 of the high-frequency scissors forceps 100 are advanced to the lower part of the lesion portion 300, and the lower part of the lesion portion 300 is incised with the pair of claws 102. When the lesion portion 300 is completely incised, with the lesion portion 300 grasped by the pair of grasping portions 204, the grasping forceps 200 are pulled in the Y(-) side to take out the lesion portion 300 outside the endoscope 10. The above is an example of the treatment method in ESD.

[0044] FIG. 7 shows an example of the biological image 400 projected on the display 16 in the above treatment. When explaining the biological image 400 shown in FIG. 7, in addition to the up-down (Z-axis) and left-right (X-axis), the so-called clock position expressed from 1 o'clock to 12 o'clock is used for the explanation.

[0045] According to the biological image 400 of FIG. 7, the high-frequency scissors forceps 100 led out from the first treatment tool outlet 52 (see FIG. 2) are observed as an image moving from a position approximately at 6 o'clock below the screen towards the lesion 300 at the center of the screen. That is, as shown in FIG. 2, the endoscope 10 of the embodiment has a configuration in which the observation window 46 is arranged in the tip surface area 40A above the horizontal axis H, and the first treatment tool outlet 52 is arranged in the tip surface area 40B below the horizontal axis H. Specifically, the tip surface 40 of the endoscope 10 is divided into four parts by the horizontal axis H and the vertical axis V. Among the divided areas, the upper right divided area is defined as the first quadrant 70A, the upper left divided area is defined as the second quadrant 70B, the lower left divided area is defined as the third quadrant 70C, and the lower right divided area is defined as the fourth quadrant 70D. In this case, the observation window 46 is arranged in the first quadrant 70A, and the first treatment tool outlet 52 is arranged in the fourth quadrant 70D. Thereby, the high-frequency scissors forceps 100 led out from the first treatment tool outlet 52 (see FIG. 2) are observed as an image moving from a position approximately at 6 o'clock below the screen towards the lesion 300 at the center of the screen.

[0046] Also, according to the biological image 400 of FIG. 7, the liquid 60 ejected from the front water inlet 56 (see FIG. 2) is observed as an image moving from a position between 7 o'clock and 8 o'clock in the lower left of the screen towards the lesion 300 at the center of the screen. That is, the endoscope 10 of the embodiment has a configuration in which the position of the center 56A of the front water inlet 56 in the direction of the vertical axis V is arranged 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. Specifically, 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 inlet 56 is offset and arranged on the outer periphery 40C side of the tip surface 40 on the side opposite to the center C side of the tip surface 40. Thereby, the liquid 60 ejected from the front water inlet 56 is observed as an image moving from a position between 7 o'clock and 8 o'clock in the lower left of the screen of FIG. 7 towards the lesion 300 at the center of the screen.

[0047] Here, a comparative example compared with the endoscope 10 of the embodiment will be briefly described. For example, when the treatment tool outlet and the front water supply port are arranged in the upper end face region with respect to the observation window in the direction of the vertical axis V shown in FIG. 2, in the biological image projected on the display, the treatment tool led out from the treatment tool outlet is observed as an image moving from a position, for example, from 11 o'clock to 1 o'clock above the screen toward the center of the screen. Therefore, for an operator performing a treatment while viewing the biological image 400, there may be a case where the treatment tool gets in the way and it becomes difficult to see the lesion (that is, the lesion is hidden by the treatment tool). And for the liquid jetted from the front water supply port, there may also be a case where it is difficult to see whether the treatment tool gets in the way and hits the lesion accurately. As a result, in the above comparative example, it may be difficult to accurately perform the treatment with the treatment tool.

[0048] On the other hand, the endoscope 10 of the embodiment is configured to arrange the first treatment tool outlet 52 in the lower end face region with respect to the observation window 46. Specifically, the observation window 46 is arranged in the upper end face region 40A above the horizontal axis H, and the first treatment tool outlet 52 is arranged in the lower end face region 40B below the horizontal axis H. More specifically, the observation window 46 is arranged in the first quadrant 70A, and the first treatment tool outlet 52 is arranged in the fourth quadrant 70D. As a result, as shown in FIG. 7, the high-frequency scissors forceps 100 are observed as an image moving from a position of approximately 6 o'clock below the screen toward the lesion 300 at the center of the screen. As a result, when performing a treatment while observing the lesion 300 on the biological image 400, the high-frequency scissors forceps 100 do not get in the way, and it is possible to accurately perform the treatment with the high-frequency scissors forceps 100 while observing the lesion 300.

[0049] In addition, the endoscope 10 of the embodiment is configured such that the forward water supply port 56 is disposed in the tip surface region below the observation window 46. Specifically, the position of the center 56A of the forward 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. More specifically, the forward water supply port 56 is offset and disposed on the outer periphery 40C side of the tip surface 40 on the side opposite to the center C side of the tip 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. As a result, the liquid 60 and the high-frequency forceps 100 are projected without overlapping on the biological image 400. As a result, it becomes easier to see whether the liquid 60 jetted from the forward water supply port 56 accurately hits the lesion part.

[0050] Therefore, according to the endoscope 10 of the embodiment, the observation window 46 is disposed in the tip surface region 40A above the horizontal axis H, and the first treatment tool outlet 52 is disposed in the tip surface region 40B below the horizontal axis H. The position of the center 56A of the forward 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. Therefore, it is possible to accurately perform a treatment using the high-frequency forceps 100.

[0051] In FIG. 2, the observation window 46 and the first treatment tool outlet 52 are shown to be completely included in the corresponding regions (that is, the tip surface region 40A and the tip surface region 40B), respectively. However, the present invention is not necessarily limited to this configuration, and it is sufficient that the observation window 46 and the first treatment tool outlet 52 are mainly disposed in the corresponding regions. Similarly, in FIG. 2, the observation window 46, the first treatment tool outlet 52, and the second treatment tool outlet 54 are shown to be completely included in the corresponding regions (that is, the first quadrant 70A, the fourth quadrant 70D, and the third quadrant 70C), respectively. However, the present invention is not necessarily limited to this configuration, 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 the corresponding regions.

[0052] Here, the above-mentioned "mainly arranged" means a case where most (more than half) of the component to be arranged (for example, the observation window 46) is included in its corresponding region (in the case of the observation window 46, it is the front end face region 40A). That is, it is not limited to the configuration where the above-mentioned component is completely included in its corresponding region. As long as most of the above-mentioned component is included in its corresponding region, a configuration where at least a part of the above-mentioned component is arranged outside its corresponding region also corresponds to the above-mentioned "mainly arranged" case. In the following description, the same meaning is also possessed when it is described as "mainly arranged".

[0053] Even when the observation window 46 is mainly arranged in the front end face region 40A and the first treatment tool outlet 52 is mainly arranged in the front end face region 40B in this way, since the high-frequency scissors forceps 100 can be observed as an image moving from the lower side of the biological image 400 toward the lesion 300 at the center of the screen, it is possible to accurately perform the treatment using the high-frequency scissors forceps 100. However, by configuring the observation window 46 to be completely included in the front end face region 40A and configuring the first treatment tool outlet 52 to be completely included in the front end face region 40B, it becomes possible to more accurately perform the treatment using the high-frequency scissors forceps 100. Furthermore, by arranging the observation window 46 in the first quadrant 70A and arranging the first treatment tool outlet 52 in the fourth quadrant 70D, since the high-frequency scissors forceps 100 can be observed as an image moving from a position approximately at 6 o'clock below the screen toward the lesion 300 at the center of the screen, it becomes possible to perform the treatment using the high-frequency scissors forceps 100 even more accurately.

[0054] In the embodiment, as a preferred mode, a form in which the front water inlet 56 is completely shifted to the outer periphery 40C side from the line L1 is shown, but it is not limited to this. As long as at least the center 56A of the front water inlet 56 is shifted to the outer periphery 40 C side from the line L1. That is, even in a form where the center 56A of the front water inlet 56 is arranged at a position shifted to the outer periphery 40 C side from the line L1, the same effects as those of the embodiment can be achieved.

[0055] Also, in the above offset arrangement, the front water inlet 56 is preferably mainly arranged in the fourth quadrant 70D. In this case, the liquid 60 jetted from the front water inlet 56 is observed as an image heading from the position of 7 o'clock to 8 o'clock below the screen Left toward the lesion 300 at the center of the screen, so even in this case, it is easier to see whether the liquid 60 jetted from the front water inlet 56 hits the lesion accurately.

[0056] The endoscope 10 of the embodiment described above has a configuration having the first treatment tool outlet 52 and the second treatment tool outlet 54. However, in the case of an endoscope having only the first treatment tool outlet 52 as the treatment tool outlet, the first treatment tool outlet 52 may be mainly arranged in the third quadrant 70C. In this case, the high-frequency scissors forceps 100 is observed as an image heading from the position of 4 o'clock to 5 o'clock in the lower right of the screen toward the lesion 300 at the center of the screen. Therefore, when performing a treatment while observing the lesion 300 on the biological image 400, the high-frequency scissors forceps 100 does not get in the way, and the treatment by the high-frequency scissors forceps 100 can be accurately performed while observing the lesion 300.

[0057] Hereinafter, the specific arrangement forms of the observation window 46, the first treatment tool outlet 52, the second treatment tool outlet 54, the front water inlet 56, the illumination windows 42 and 44, and the air and water supply nozzle 58 arranged on the distal end surface 40 of FIG. 2 will be described with reference to FIG. 2.

[0058] First, a first treatment tool outlet 52 is disposed below the observation window 46, and a second treatment tool outlet 54 is disposed below the observation window 46 and laterally of the first treatment tool outlet 52. Specifically, the observation window 46 is disposed 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. By satisfying the above-described arrangement relationship, as shown in FIG. 7, the high-frequency forceps 100 are observed as an image moving from a position approximately at 6 o'clock below the screen toward the lesion 300 at the center of the screen, and the grasping forceps 200 are observed as an image moving from a position between 4 o'clock and 5 o'clock at the lower right of the screen toward the lesion 300 at the center of the screen. That is, since the high-frequency forceps 100 and the grasping forceps 200 are projected on the biological image 400 without overlapping, the high-frequency forceps 100 and the grasping forceps 200 are more visible. As a result, it becomes possible to perform the treatment using the high-frequency forceps 100 and the grasping forceps 200 more accurately.

[0059] Further, since the grasping forceps 200 have more functions (bending function) than the high-frequency forceps 100, the diameter of the grasping forceps 200 is larger than that of the high-frequency forceps 100. For this reason, the second treatment tool outlet 54 has a larger diameter than the diameter of the first treatment tool outlet 52. Since the second treatment tool outlet 54 is disposed in the third quadrant 70C, the image area occupied by the image of the grasping forceps 200 in the biological image 400 can be reduced. Thereby, the high-frequency forceps 100 become even more visible, so that it becomes possible to accurately perform the treatment using the high-frequency forceps 100.

[0060] Further, the distal end surface 40 includes a first surface 41A and a second surface 41B protruding from the first surface 41A in the distal end direction (Y(+) direction) of the insertion portion 20. A forward water inlet 56 is disposed on the first surface 41A, and an 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, a fan-shaped second surface 41B is formed in the first quadrant 70A in plan view, 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.

[0061] By adopting a configuration in which the observation window 46 is disposed on the second surface 41B and the front water supply port 56 is disposed on the first surface 41A, it is possible to suppress halation (a phenomenon in which an image becomes white) and the like caused by the residual water of the liquid 60 that has risen in the Y(+) direction from the front water supply port 56. Specifically, when the water supply of the liquid 60 from the front water supply port 56 is completed, the Open residual water of the liquid 60 rises in the Y(+) direction due to the influence of surface tension at the opening of the front water supply port 56. As a result, there is a concern that the rising residual water may be reflected on the screen, or the illuminated light may be reflected by the rising residual water to cause halation. On the other hand, the endoscope 10 of the embodiment has a configuration in which the observation window 46 is disposed on the second surface 41B and the front water supply port 56 is disposed on the first surface 41A. Therefore, it is possible to suppress the reflection of the residual water and halation caused by the above-mentioned rising residual water, and a good image can be projected.

[0062] Also, in the configuration in which the observation window 46 is disposed on the second surface 41B and the front water supply port 56 is disposed on the first surface 41A, the illumination window 42 (the first illumination window) is further disposed on the second surface 41B. Thereby, it is possible to suppress the adhesion of the residual water of the front water supply port 56 to the illumination window 42. As a result, it is possible to suppress a decrease in the amount of illumination light and halation caused by the adhesion of the residual water to the illumination window 42.

[0063] The illumination window 44 corresponding to the second illumination window is disposed on the first surface 41A. This illumination window 44 is located on the side opposite to the side where the front water supply port 56 is disposed with the observation window 46 interposed therebetween, and is disposed at a position farther from the front water supply port 56 than the illumination window 42. For this reason, since the residual water of the front water supply port 56 is less likely to adhere to the illumination window 44 than to the illumination window 42, it is possible to dispose the illumination window 44 on the first surface 41A. Needless to say, the illumination window 44 may be disposed on the second surface 41B in the same manner as the illumination window 42.

[0064] Also, the air and water supply nozzle 58 is disposed in the second quadrant 70B. As a result, the second quadrant 70B, which is spatially unoccupied, can be effectively utilized as the placement space for the air and water supply nozzle 58. As a result, the tip 26 can be made smaller in diameter.

[0065] Also, the illumination window 44 (second illumination window) is offset and disposed on the outer peripheral 40C side of the distal end surface 40, on the side opposite to the center C side of the distal end surface 40, with respect to the line L2 connecting the center 46A of the observation window 46 and the center 58A of the air and water supply nozzle 58. The reason why such an arrangement is desirable will be described below.

[0066] 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, when 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 grasping portions 204, becomes disturbing light, and is received by the imaging element through the observation window 46, and halation may occur. In the endoscope 10 of the embodiment, since the illumination window 44 is offset and disposed at a position away from the second treatment tool outlet 54 as described above, it is possible to suppress the disturbing light from being received by the imaging element. As a result, halation caused by the grasping forceps 200 led out from the second treatment tool outlet 54 can be suppressed, and a good image can be displayed.

[0067] In the embodiment, as a preferred aspect, the form in which the illumination window 44 is completely displaced to the outer peripheral 40F side from the line L2 is shown. However, the present invention is not limited to this, and at least the center 44A of the illumination window 44 may be displaced to the outer peripheral 40C side from the line L2. That is, even in the form in which the illumination window 44 is disposed at a position overlapping the line L2, the same effect as that of the embodiment can be achieved.

[0068] Further, 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 curved portion 202 of the grasping forceps 200 is curved, it is possible to suppress 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.

[0069] In the embodiment, as a preferred mode, the form in which the center 44A of the illumination window 44 is arranged at a position overlapping the vertical axis V is shown. However, the present invention is not limited to this, and at least a part of the illumination window 44 may be arranged on the vertical axis V. That is, even in the form in which a part of the illumination window 44 is arranged on the vertical axis V, the same effect as that of the embodiment can be obtained.

[0070] In the embodiment described above, the endoscope 10 having two treatment tool outlets (the first treatment tool outlet 52 and the second treatment tool outlet 54) on the distal end surface 40 has been described. However, the present invention can also be applied to an endoscope having only the first treatment tool outlet. That is, on the distal end surface 40, the observation window 46 is arranged in the distal end surface area 40A above the horizontal axis H, and the first treatment tool outlet 52 is arranged in the distal end surface area 40B below the horizontal axis H. As a result, the treatment tool is observed from below the biological image toward the central part of the biological image. Image Therefore, it is possible to accurately perform the treatment with the treatment tool.

[0071] Hereinafter, some preferred forms related to the endoscope 10 of the embodiment will be described.

[0072] <Regarding the adjustment of the mounting position of the observation window> First, the case where the first treatment tool outlet 52 is arranged directly below the observation window 46 in the vertical axis V direction will be described. In the observation image, the derivation position of the treatment tool observed in the observation image changes depending on the mounting position of the observation window 46. An example thereof will be described with reference to FIG. 8.

[0073] Reference numeral VIIIA in Fig. 8 shows 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 when looking at the front end face 40 from the Y(+) direction with respect to a line parallel to the vertical axis V. Reference numeral VIIIB shows an observation image 504 when the line connecting the center 46A of the observation window 46 and the center 52A of the first treatment tool outlet 52 is inclined 10 degrees to the right when looking at the front end face 40 from the Y(+) direction with respect to a line parallel to the vertical axis V. Reference numeral VIIIC shows an observation image 506 when the line connecting the center 46A of the observation window 46 and the center 52A of the first treatment tool outlet 52 is inclined 7 degrees to the left when looking at the front end face 40 from the Y(+) direction with respect to a line parallel to the vertical axis V. In this example, for the sake of convenience of explanation, the form in the case where the center 46A of the observation window 46 and the center of the observation optical system are pre-aligned on the same straight line will be described. However, when 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 shall be adjusted.

[0074] In the observation image 502, the high-frequency scissors forceps 100 are observed to be derived from directly below the observation image 502 (the 6 o'clock position) toward the center of the observation image 502. On the other hand, in the observation image 504, it is observed to be derived from the lower left of the observation image 504, and in the observation image 506, it is observed to be derived from the lower right of the observation image 506.

[0075] Thus, depending on the mounting position of the observation window 46, in the observation image, the high-frequency scissors forceps 100 appear to be derived from different positions. Therefore, it may affect the operator's technique.

[0076] Therefore, in order to solve such a problem, the mounting 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 derivation position of the high-frequency scissors forceps 100 in the observation image appears to be constant. Thereby, the operator can perform the treatment with a stable technique.

[0077] As a method for adjusting the mounting position of the observation window 46, it can be performed by adjusting the position of the observation window 46 using an adjustment jig while observing the image captured by the observation optical system.

[0078] <Regarding the bending operation mechanism> Next, among the configurations of the hand operation unit 18, for bending the bending portion 24 Of An example of the bending operation mechanism will be described. FIG. 9 is a schematic cross-sectional view of the hand operation unit 18, and a part of the bending portion 24 is also shown as a cross-sectional view in the figure. Further, FIG. 9 shows a bending operation mechanism for bending the bending portion 24 in the vertical direction among the bending operation mechanisms for bending the bending portion 24. Since the bending operation mechanism for bending in the left-right direction has the same mechanism, the illustration is omitted. Hereinafter, the former bending operation mechanism will be described, and the description of the latter bending operation mechanism will be omitted.

[0079] As shown in FIG. 9, the bending portion 24 has, as an example, a plurality of bending pieces 552 having a substantially cylindrical shape, and a plurality of rivet pins 554 that connect adjacent bending pieces 552 to each other. The adjacent bending pieces 552 are rotatably connected to each other about the rivet pin 554.

[0080] On the other hand, in the flexible portion 22 and the bending portion 24, for example, as shown in FIGS. 12 to 14, in addition to the built-in objects such as the first treatment tool channel 714, the second treatment tool channel 716, the liquid supply pipe 708, the liquid supply pipe 710, the gas supply pipe 712, the signal cable 702, and the 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 respectively inserted. The two pairs of angle wires 556 are respectively arranged along the long axis Ax direction of the insertion portion 20, and are engaged with the bending pieces 552 by being respectively inserted into the holes 720 of the pins 722a, 722b, 722c, and 722d provided inside the rivet pins 554 of the bending portion 24.

[0081] Also, among the two pairs of angled wires 556, the tip portions of the pair of angled wires 556 for vertical direction operation are respectively fixed to the tip portion 26, and the base end portions of the pair of angled wires 556 are respectively joined to a pair of sleeves 557 for vertical direction operation shown in FIG. 9. Thus, by pushing and pulling the pair of angled wires 556 via the pair of sleeves 557, the curved portion 24 is curved in the vertical direction.

[0082] The bending operation mechanism 558 for vertical direction operation provided inside the hand 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 end portions of this chain 562.

[0083] The sprocket 560 is connected to an angle knob 28 (see FIG. 1) for vertical direction operation via a rotation shaft 560A and is rotated along with the rotation operation of the angle knob 28. Thus, the pair of angled wires 556 are pushed and pulled via the chain 562 and the pair of sleeves 557. That is, one of the pair of angled wires 556 is pulled toward the base end side and the other is sent out toward the tip end side.

[0084] Here, stoppers 564A and 564B are provided on the base end sides of the sleeves 557, 557 to regulate the movement of the sleeves 557, 557 toward the base end side by contacting the sleeves 557, 557. The positions of the stoppers 564A and 564B can be adjusted respectively, and the movement of the sleeves 557, 557 is regulated by the stoppers 564A and 564B. As a result, the maximum bending angle in the vertical direction of the curved portion 24 is defined.

[0085] Further, with respect to the positions of the stoppers 564A and 564B, the position of the stopper 564A that restricts the Up side (Z(+) direction side) is set to the proximal end side with respect to the position of the stopper 564B that restricts the Down side (Z(-) direction side). As a result, the curved portion 24 curves at a larger angle toward the Up side than the Down side. As a result, when the curved portion 24 is curved toward the Up side, the body wall on the side opposite to the insertion direction of the insertion portion 20 can be observed. In this case, although the bending angle toward the Down side becomes small (for example, 90 degrees on the Down side while 210 degrees on the Up side), since the Up side is mainly used in the endoscope, there is no problem in using the endoscope.

[0086] On the other hand, when bending the curved portion 24, in an endoscope that requires a large pulling force (large torque) (for example, an endoscope that uses two treatment tools simultaneously), even if the angle knob 28 is operated, the angle wire 556 may extend and may not contribute to the bending operation of the curved portion 24. To prevent this problem, the position of the stopper 564A that restricts the Up side is arranged further toward the proximal end side. As a result, the angle wire 556 can be pulled including the amount of extension of the angle wire 556, so that even an endoscope with a large torque can be bent toward the Up side. Thus, 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.

[0087] <Regarding the curved portion> Next, an example of the configuration of the curved portion 24 will be described. FIG. 10 is a diagram (graph) showing the relationship between the torque (pulling force) generated when bending the curved portion 24 and the bending angle of the curved portion 24. FIG. 11 is a diagram showing the connection form of a plurality of curved pieces 552 constituting the curved portion 24.

[0088] In the endoscope having torque fluctuations shown by line LA in FIG. 10 (hereafter referred to as endoscope A), the bending section 24 can be bent with a gradually increasing torque up to a certain angle. However, when it exceeds a certain bending angle (190 degrees in line LA), it has an inflection point where a larger torque is required. Therefore, in this endoscope A, as long as the bending angle is up to 190 degrees, the bending operation of the bending section 24 can be performed without problems. However, when the bending angle exceeds 190 degrees, a larger torque is required, which places a burden on the operator. Also, even if traction is applied with a large torque, the angle wire 556 stretches, so it may not be possible to obtain a predetermined bending angle with respect to the traction force.

[0089] Note that line LA was measured with the built-in object included inside the bending section. However, this tendency is the same even when the built-in object is not included. When measuring the torque and the bending angle with only the bending section of endoscope A without the built-in object, it was confirmed that it has an inflection point at 225 degrees.

[0090] Therefore, the bending section 24 is configured as follows to increase the angle of the inflection point in the state where the built-in object is not included inside the bending section 24 to be larger than the above-mentioned 225 degrees, thereby solving the above problems. Hereinafter, the configuration of the bending section 24 will be described.

[0091] That is, as shown in FIG. 11, in the circumferential direction of the bending piece 552 that constitutes the bending section 24, a pair of connecting pieces 602 formed in a tongue shape protrude along the Y-axis 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, and a rivet pin 606 is attached to the through hole 604 formed in the connecting piece 602, and adjacent bending pieces 552 are connected. As a result, a plurality of bending pieces 552 are rotatably connected in the vertical direction via two rivet pins 606, 606 arranged in the left-right direction.

[0092] In order to bend the bending portion 24 at an angle larger than the previous one, for example, the following can be done. That is, the inclination angle of the end portions 608 with respect to the Z-axis is increased so that the end portions 608, 608 facing each other in the Y-axis direction of the adjacent bending pieces 552 are separated from each other in the Y-axis direction. As a result, when the bending portion 24 is bent, the bending angle of the bending portion 24 becomes larger than the previous one. As a result, the inflection point of the bending portion 24 alone can be, for example, 225 degrees or more, and the inflection point of the bending portion 24 including the built-in object can be, for example, 205 degrees or more (refer to the endoscope B shown by the line LB in FIG. 10).

[0093] Note that the bending piece for increasing the inclination angle of the end portion 608 is preferably the bending piece 552 in the middle portion excluding the tip-side bending piece 552 connected to the tip portion 26 and the base-end-side bending piece 552 connected to the flexible portion 22 among the plurality of bending pieces 552 connected in the Y-axis direction.

[0094] That is, the position of the tip-side bending piece 552 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 it is a portion with high rigidity due to the hardening of the adhesive. Therefore, when the inclination angle of the end portion 608 is increased in the tip-side bending piece 552, a large torque is required to bend this portion (the portion with increased rigidity), so it is preferable to keep the tip-side bending piece 552 the same as before.

[0095] Also, the position of the base-end-side bending piece 552 in the Y-axis direction is the starting point for bending the bending portion 24. Therefore, when the inclination angle of the end portion 608 is increased in the base-end-side bending piece 552, the tip portion 26 of the endoscope 10 will rise high at the position of that bending piece 552. As a result, the curvature when the bending portion 24 is bent becomes smaller, and as a result, it becomes difficult to invert the bending portion 24 with a large curvature. That is, the observation range of the endoscope 10 becomes narrower, so it is preferable to keep the base-end-side bending piece 552 the same as before.

[0096] <Regarding the internal structure of the bending section> Next, the preferred internal structure of the bending section 24 will be described. As described above, on the tip surface 40 of the endoscope 10, there are arranged 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 front water inlet 56. These are connected to the hand operation section 18 via various cables and various channels (hereinafter referred to as built-in items) inserted into the bending section 24 and the flexible section 22.

[0097] 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 front water inlet 56 are fixed to the tip portion 26. However, since the bending section 24 bends, it is preferable that the built-in items within the bending section 24 are arranged without being fixed.

[0098] By the way, when the bending operation of the bending section 24 is repeated, the built-in items may move within the bending section 24. In this case, problems such as the built-in items kinking (twisting or being distorted), the cable breaking, and the arrangement within the bending section being disturbed with respect to the arrangement of the tip surface may occur.

[0099] Therefore, in order to prevent the disturbance of the arrangement of the built-in items within the bending section 24, it is preferable to have the following configuration.

[0100] (1) Increase the outer diameters of the first treatment tool channel 714 and the second treatment tool channel 716.

[0101] FIG. 12 is a cross-sectional view showing the internal structure of the curved portion, and is a view seen from the Y(-) direction to the Y(+) direction. Inside the curved portion 24, in accordance with the arrangement of each component of the tip surface 40, when the inside of the curved portion 24 is divided into two equal parts in the Z-axis direction, among the two divided regions, on the Z(+) direction side region, a signal cable 702, light guides 704, 706, a liquid feed pipe 708 for feeding water to the front water inlet 56, a liquid supply pipe 710 for supplying liquid to the air and water nozzle 58, and a gas supply pipe 712 for supplying gas are arranged. Further, in the Z(-) direction side region, a first treatment tool channel 714 and a second treatment tool channel 716 are arranged. Also, pins 722a, 722b, 722c, 722d having holes 720 through which angle wires 556 for bending the curved portion 24 pass are provided in the vertical and horizontal directions of the inner circumference inside the curved portion 24.

[0102] In the curved portion 24 shown in FIG. 12, the outer diameters of each of the first treatment tool channel 714 and the second treatment tool channel 716 are increased, and the distance between the pins 722b and 722d facing each other in the X-axis direction is made shorter than the sum of the outer diameter of the first treatment tool channel 714 and the outer diameter of the second treatment tool channel 716.

[0103] Furthermore, it is preferable that the first treatment tool channel 714 has an outer diameter that does not move to the Z(+) direction side region by abutting against the pin 722d on the X(-) side and the second treatment tool channel 716, and the second treatment tool channel 716 has an outer diameter that does not move to the Z(+) direction side region by abutting against the pin 722b on the X(+) side and the first treatment tool channel 714.

[0104] 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 Z(+) direction side region. Also, by the first treatment tool channel 714 and the second treatment tool channel 716, it is possible to prevent the signal cable 702, the light guides 704, 706, the liquid feed pipe 708, the liquid supply pipe 710, and the gas supply pipe 712 from moving to the Z(-) direction side region. As a result, it is possible to prevent the arrangement of the built-in objects inside the curved portion 24 from being disturbed.

[0105] (2) Extend the pins toward the central part.

[0106] FIG. 13 is a diagram for explaining another embodiment for preventing the disorder of the above arrangement. In the aspect shown in FIG. 13, the pins 722b and 722d provided to face each other in the X-axis direction are extended toward the center within the curved portion 24. And the distance between the mutually opposed pins 722b and 722d is made shorter than the outer diameters of the first treatment tool channel 714 and the second treatment tool channel 716.

[0107] Thereby, it is possible to prevent the first treatment tool channel 714 and the second treatment tool channel 716 from moving to the region on the Z(+)-direction side from the pins 722d and 722b provided in the X-axis direction. As a result, it is possible to prevent the disorder of the arrangement within the curved portion 24.

[0108] Further, by configuring the shapes of the pins 722b and 722d of each bending piece 552 of the curved portion 24 as described above, the force applied to the pins 722b and 722d can be dispersed, and it is possible to prevent the pins 722b and 722d from being damaged.

[0109] (3) Provide a partition member within the curved portion.

[0110] FIG. 14 is a diagram for explaining yet another embodiment for preventing the disorder of the above arrangement. In the aspect shown in FIG. 14, it has a partition member 724 in the region on the Z(+)-direction side. The partition member 724 is a component housed in the region on the Z(+)-direction side, and is provided so as to surround the signal cable 702, the light guides 704 and 706, the liquid delivery pipe 708, the liquid supply pipe 710, and the gas supply pipe 712.

[0111] Thereby, it is possible to prevent various cables and various channels from being interchanged between the region on the Z(+)-direction side and the region on the Z(-)-direction side, and as a result, it is possible to prevent the disorder of the arrangement of the built-in objects.

[0112] Incidentally, the position where the partition member 724 is provided can be set at any position within the curved portion 24. The partition member 724 can be fixed by spot welding and can be assembled by inserting it into the curved portion after assembling the curved portion.

[0113] As described above, the endoscope according to the embodiment has been described. However, the present invention may be subject to some improvements or modifications without departing from the gist of the present invention.

Explanation of Signs

[0114] 10 Endoscope 12 Endoscope system 14 Processor device for endoscope 16 Display 18 Hand operation unit 20 Insertion portion 22 Flexible portion 24 Curved portion 26 Tip portion 28 Angle knob 30 Angle knob 31A Air and 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 40A Upper tip surface area 40B Lower tip surface area 40C Outer periphery 41A First surface 41B Second surface 42 Lighting window 44 Lighting window 44A Center 46 Observation window 46A Center 48 First treatment tool inlet 50 Second treatment tool inlet 52 First treatment tool outlet 52A Center 54 Second treatment tool outlet 54A Center 56 Front water supply port 56A Center 58 Air and water supply nozzle 58A Center 60 Liquid 70A First quadrant 70B Second quadrant 70C Third quadrant 70D Fourth quadrant 100 High-frequency scissors forceps 102 Claw 200 Grasping forceps 202 Bending part 204 Grasping part 300 Lesion part 400 Biometric image 502 Observation image 504 Observation image 506 Observation image 552 Bending piece 554 Rivet pin 556 Angle wire 557 Sleeve 558 Bending operation mechanism 560 Sprocket 560A Rotation axis 562 Chain 564A Stopper 564B Stopper 602 Connecting piece 604 Through hole 606 Rivet pin 608 End part 702 Signal cable 704 Light guide 706 Light guide 708 Liquid delivery pipe 710 Liquid supply pipe 712 Gas supply pipe 714 First treatment tool channel 716 Second treatment tool channel 720 Hole 722a Pin 722b Pin 722c pin 722d pin 724 partition member H horizontal axis V vertical axis L1 line L2 line LA line LB line Ax major axis C center

Claims

1. An observation window disposed on the tip surface of an insertion portion that can be bent in the vertical and horizontal directions for observing the inside of a subject, a first treatment tool outlet disposed on the tip surface and capable of guiding out a first treatment tool, a forward water supply port disposed on the tip surface for injecting liquid toward an observation site in the subject, comprising, When looking at the tip surface from the front, among two axes passing through the center of the tip surface and perpendicular to each other, the axis parallel to the horizontal direction is defined as the first axis, and the axis parallel to the vertical direction is defined as the second axis. Among the divided regions obtained by dividing the tip surface into four by the first axis and the second axis, when the upper right divided region is defined as the first quadrant, the upper left divided region is defined as the second quadrant, the lower left divided region is defined as the third quadrant, and the lower right divided region is defined as the fourth quadrant, the center of the observation window is disposed in the first quadrant, the center of the first treatment tool outlet is disposed in the fourth quadrant or the third quadrant, the central position of the forward water supply port in the direction of the second axis is disposed between the central position of the observation window and the central position of the first treatment tool outlet in the direction of the second axis, the forward water supply port is offset and disposed on the outer peripheral side of the tip surface opposite to the center side of the tip surface with respect to the line connecting the center of the observation window and the center of the first treatment tool outlet, the center of the forward water supply port is disposed in the fourth quadrant, an endoscope.

2. An observation window disposed on the tip surface of an insertion portion that can be bent in the vertical and horizontal directions for observing the inside of a subject, a first treatment tool outlet disposed on the tip surface and capable of guiding out a first treatment tool, a forward water supply port disposed on the tip surface for injecting liquid toward an observation site in the subject, comprising, When looking at the tip surface from the front, among two axes passing through the center of the tip surface and perpendicular to each other, the axis parallel to the horizontal direction is defined as the first axis, and the axis parallel to the vertical direction is defined as the second axis. Among the divided regions obtained by dividing the tip surface into four by the first axis and the second axis, when the upper right divided region is defined as the first quadrant, the upper left divided region is defined as the second quadrant, the lower left divided region is defined as the third quadrant, and the lower right divided region is defined as the fourth quadrant, having an air and water supply nozzle in the second quadrant, the center of the observation window is disposed in the first quadrant, the center of the first treatment tool outlet is disposed in the fourth quadrant, the central position of the forward water supply port in the direction of the second axis is disposed between the central position of the observation window and the central position of the first treatment tool outlet in the direction of the second axis, an endoscope.

3. The tip surface has a second illumination window, the second illumination window is offset and arranged on the outer peripheral side of the tip surface on the side opposite to the center side of the tip surface with respect to the line connecting the center of the observation window and the center of the air and water supply nozzle, The endoscope according to claim 2.

4. the second illumination window is arranged on the second axis, The endoscope according to claim 3.

5. the front water supply port is offset and arranged on the outer peripheral side of the tip surface on the side opposite to the center side of the tip surface with respect to the line connecting the center of the observation window and the center of the first treatment tool outlet, The endoscope according to claim 4.

6. the center of the front water supply port is arranged in the fourth quadrant, The endoscope according to claim 5.

7. the tip surface has a second treatment tool outlet through which a second treatment tool can be led out, the center of the first treatment tool outlet is arranged in the fourth quadrant, the center of the second treatment tool outlet is arranged in the third quadrant, The endoscope according to any one of claims 1 to 6.

8. the second treatment tool outlet has a larger diameter than the diameter of the first treatment tool outlet, The endoscope according to claim 7.

9. the tip surface includes a first surface and a second surface protruding from the first surface in the tip direction of the insertion portion, the front water supply port is arranged on the first surface, the observation window is arranged on the second surface, The endoscope according to any one of claims 1 to 8.

10. the second surface has a first illumination window, The endoscope according to claim 9.

Images