Operation mechanism of insertion apparatus, and insertion apparatus

Abstract

The present invention comprises: wires 37, 38 that act by reciprocating between an operation part 6 and the distal end of an insertion part 5 inserted into a subject in the longitudinal direction of an insertion apparatus 1; pulleys 51, 52 that rotate about a central axis O3 in response to an operation from the outside, the pulleys 51, 52 including drums drum 51a, 52a around which a wire is wound for at least one circumference, and a flange 51c for preventing detachment of the wires from the drums; and a wire-fixing part 51d that fixes the wires to the pulleys. The drums are configured such that the cross-sectional shape orthogonal to the central axis has a non-circular oval shape in which the radius of a portion where the wire-fixing part is not provided is formed so as to be less than the radius of a portion where the wire-fixing part is provided.

Description

Insertion device operating mechanism and insertion device

[0001] The present invention relates to an operation mechanism that operates by operating an operation member provided in an operation section in an insertion instrument such as an endoscope, and to an insertion instrument equipped with such an operation mechanism.

[0002] Conventionally, insertion instruments such as endoscopes have been widely used in, for example, the medical field and the industrial field. Generally, insertion instruments such as endoscopes are configured to include an insertion section formed in a flexible, elongated tube shape and an operation section provided adjacent to the base end of the insertion section and having various operation members and the like on its outer surface. For example, in a medical endoscope, the insertion section is inserted into a body cavity of a subject to enable observation of the inside of the body cavity.

[0003] A typical endoscope is configured with a bending portion formed to be freely bendable in a partial region near the tip of the insertion portion. This bending portion realizes a predetermined bending movement through a bending operation mechanism that operates in response to the rotation of an operation member (bending operation member) provided in the operation portion.

[0004] Specifically, for example, when the bending operation member is rotated, the amount of operation force rotates a pulley, which is a rotating body connected to the bending operation member. Here, the base ends of multiple pulling wires inserted into the insertion portion are fixed to the pulley. As a result, when the pulley rotates, the pulling wires are wound around the outer peripheral surface of the pulley. In addition, the tips of the multiple pulling wires are fixed to the bending portion. With this configuration, the multiple pulling wires move forward and backward inside the insertion portion in a direction along the longitudinal axis, thereby pulling the bending portion. This realizes bending of the bending portion in a predetermined direction.

[0005] Meanwhile, in recent years, so-called single-use endoscopes that are disposed of after a single use have become increasingly popular in the field of medical endoscopes, for example, in order to take infection control measures into consideration, etc. This type of single-use endoscope has the advantage that cleaning and sterilization processes are not required.

[0006] Furthermore, there is a constant demand for reduced manufacturing costs and lower product prices for conventional endoscopes, and such demands are particularly strong for single-use endoscopes. To this end, various proposals have been made for conventional endoscopes, such as for simplifying the structure without compromising operability or for reducing the number of manufacturing steps, as disclosed in, for example, Japanese Patent Publication Nos. 2016-59571, 2000-12619, 2010-119556, and 2017-46825.

[0007] For example, in conventional endoscopes, it has been proposed to simplify the structure without impairing operability by devising the outer peripheral shape of the pulley that winds up the traction wire in the bending operation mechanism, or by devising the winding pattern of the traction wire around the pulley.

[0008] Furthermore, in conventional endoscopes, it has been proposed to simplify the structure by, for example, fixing a wire stator to one end of a pulling wire by caulking, and fitting the wire stator into a fixed portion of a pulley, thereby detachably connecting the pulling wire to the pulley.

[0009] In conventional endoscopes, these improvements have simplified the structure, contributing to a reduction in manufacturing costs and also to improved operability.

[0010] However, in conventional endoscopes, when a structure in which a wire stator is connected to a pulley is adopted as described above, providing a wire fixing portion on the pulley tends to increase the outer diameter around which the traction wire is wound, which results in an increase in the load radius of the pulley caused by the traction wire, thereby increasing the rotational torque when rotating the bending operation member, resulting in a problem of impaired operability.

[0011] The present invention aims to provide an operating mechanism for an insertion device such as an endoscope, for example, a bending operation mechanism equipped with a pulley that winds up a traction wire, which has a structure that can suppress an increase in the rotational torque of an operating member during bending operation, and the insertion device.

[0012] In order to achieve the above object, one embodiment of the operating mechanism of an insertion device of the present invention includes a wire that acts on a subject by reciprocating between the tip of an insertion section that is inserted longitudinally of the insertion device and an operating section that is arranged on the base end side of the insertion section, a drum that wraps the wire around itself at least once, a flange that prevents the wire from falling off the drum, a pulley that rotates around a central axis in response to external operation, and a wire fixing section that fixes the wire to the pulley, and the cross-sectional shape of the drum perpendicular to the central axis is formed so that the radius of the portion where the wire fixing section is not provided is smaller than the radius of the portion where the wire fixing section is provided, and the drum has a non-circular oval shape.

[0013] An insertion instrument according to one aspect of the present invention includes an insertion section that is inserted into a subject in the longitudinal direction of the insertion instrument, a wire that acts by reciprocating between the tip of the insertion section and an operation section disposed on the base end side of the insertion section, a drum that wraps the wire around itself at least once, and a flange configured to prevent the wire from falling off the drum, the drum also having a pulley that rotates about a central axis in response to external operation, and a wire fixing section that fixes the wire to the drum, and the cross-sectional shape of the drum perpendicular to the central axis is formed such that the radius of the portion where the wire fixing section is provided is smaller than the radius of the portion where the wire fixing section is not provided, and the drum has a non-circular oval shape.

[0014] According to the present invention, it is possible to provide an operating mechanism for an insertion device such as an endoscope, for example, a bending operation mechanism equipped with a pulley that winds up a traction wire, which has a structure that can suppress an increase in the rotational torque of the operating member during bending operation, and the insertion device.

[0015] 6 is an external perspective view showing a schematic configuration of an endoscope as an example of an insertion instrument according to a first embodiment of the present invention; an external perspective view of the tip of the endoscope in FIG. 1; a front view of the tip as seen from the direction of arrow [3] in FIG. 2; a top view of a main part of the tip as seen from the direction of arrow [4] in FIG. 3; a cross-sectional view of a main part along line [5]-[5] in FIG. 3; a cross-sectional view along the longitudinal axis direction of a bending part of the endoscope in FIG. 1; a cross-sectional view along line [7]-[7] in FIG. 6; a schematic perspective view of the bending part in FIG. 6 as seen from the base end side; a schematic perspective view showing only an elevator operation wire restricting member; a schematic perspective view showing a modified example of an elevator operation wire restricting member; a cross-sectional view taken along the line

[12] -

[12] in FIG. 11; a cross-sectional view taken along the line

[13] -

[13] in FIG. 11; a cross-sectional view of the connection between the bending section and the flexible tube section of the endoscope in FIG. 1; a cross-sectional view taken along the line

[15] -

[15] in FIG. 14; an exploded perspective view of the tip end side of the flexible tube section of the endoscope in FIG. 1; a schematic perspective view of the assembled state of the tip end side of the flexible tube section of the endoscope in FIG. 1; an exploded perspective view of the operation section of the endoscope in FIG. 1; a cross-sectional view showing the second housing side at the connection between the operation section and the flexible tube section of the endoscope in FIG. 1; a cross-sectional view taken along the line

[20] -

[20] in FIG. 25] is an exploded perspective view of the housing at the connection portion between the operation section and the flexible tube section of the endoscope of FIG. 1; a cross-sectional view taken along the line

[22] -

[22] of FIG. 21; an exploded perspective view of the housing at the connection portion between the operation section and the flexible tube section of the endoscope of FIG. 1; a cross-sectional view taken along the line

[24] -

[24] of FIG. 19; a cross-sectional view showing the connection structure at the connection portion between the operation section and the flexible tube section of the endoscope of FIG. 1; a cross-sectional view taken along the line

[26] -

[26] of FIG. 25; an exploded perspective view showing the rear end connecting member of the flexible tube section of the endoscope of FIG. 1; an enlarged cross-sectional view of the main part of the region shown in

[28] of FIG. 25; a cross-sectional view of a branch tube provided in the operation section of the endoscope of FIG. 1; and an external perspective view showing a part of the branch tube of FIG. , a plan view seen from the side of an air / liquid supply cylinder provided in the operating section of the endoscope of Figure 1, a figure showing a tube fixing member of a first modified example, a figure showing a tube fixing member of a second modified example, a figure showing a tube fixing member of a third modified example, a figure showing the tube fixing member of the third modified example of Figure 34 from a different direction, a figure showing a tube fixing member of a fourth modified example, a cross-sectional view of a suction cylinder provided in the operating section of the endoscope of Figure 1, a cross-sectional view of a bending operation mechanism provided in the operating section of the endoscope of Figure 1, an exploded perspective view showing a pulley unit in the bending operation mechanism of Figure 38 from one end side, an exploded perspective view showing the pulley unit in the bending operation mechanism of Figure 38 from the other end side,Perspective view showing an enlarged first case member, plan view schematically showing the state when the pulley for up-and-down bending rotates to the first rotation end position, plan view schematically showing the state when the pulley for up-and-down bending rotates to the second rotation end position, cross-sectional view (neutral state) showing the drum shapes of the pulley for up-and-down bending and the pulley for left-and-right bending, view showing the state with a predetermined amount of rotational force applied from the neutral state of FIG. 44, exploded perspective view showing the up-and-down bending operation knob from one end side, exploded perspective view showing the up-and-down bending operation knob from the other end side, cross-sectional view of the main part of the up-and-down bending operation knob when the brake is released, cross-sectional view of the main part of the up-and-down bending operation knob when the brake is actuated, exploded perspective view showing the left-and-right bending operation knob from one end side, exploded perspective view showing the left-and-right bending operation knob from the other end side, exploded perspective view showing the enlarged main part of the left-and-right bending operation knob from one end side, exploded perspective view showing the enlarged main part of the left-and-right bending operation knob from the other end side, perspective view showing an enlarged cam plate, cross-sectional view of the main part of the left-and-right bending operation knob when the brake is released, cross-sectional view of the main part of the left-and-right bending operation knob when the brake is actuated, enlarged cross-sectional view of the region indicated by

[57] in FIG. 38, external perspective view showing only the UD spacer, external perspective view showing only the RL spacer, enlarged cross-sectional view of the region indicated by

[60] in FIG. 38, perspective view showing the up-and-down stage operation mechanism of the endoscope of FIG. 1, cross-sectional view of the main part of the cylinder unit of the up-and-down stage operation mechanism of FIG. 61, schematic view of the wire guide frame provided inside the operation part of the endoscope of FIG. 1, schematic view showing the structure in which the bending operation wire is held by the wire guide frame of FIG. 63, exploded perspective view showing the pulley unit in the endoscope according to the second embodiment of the present invention from one end side, exploded perspective view showing the pulley unit of FIG. 65 from the other end side, plan view schematically showing the state when the pulley for up-and-down bending in the bending operation mechanism of FIG. 65 rotates to the first rotation end position of the auxiliary plate, plan view schematically showing the state when the pulley for up-and-down bending in the bending operation mechanism of FIG. 65 rotates to the second rotation end position of the auxiliary plate, plan view schematically showing the state when the pulley for up-and-down bending and the auxiliary plate in the bending operation mechanism of FIG. 65 rotate to the first rotation end position, plan view schematically showing the state when the pulley for up-and-down bending and the auxiliary plate in the bending operation mechanism of FIG. 65 rotate to the second rotation end position, perspective view showing the auxiliary plate selectively used for the pulley for up-and-down bending in the bending operation mechanism of FIG. 65FIG. 1 is a cross-sectional view of a connection portion between a bending section and a flexible tube section in a conventional endoscope.

[0016] The present invention will be described below with reference to the illustrated embodiments. The drawings used in the following description are schematic. Therefore, in these drawings, each component is shown at a size that allows it to be recognized on the drawing. For this reason, the dimensional relationships and scales of the components in the drawings may be different for each component. The present invention is not limited to the illustrated embodiments with respect to the quantities, shapes, size ratios, relative positional relationships, etc. of the components shown in the drawings.

[0017] First, the configuration of an insertion instrument according to a first embodiment of the present invention will be described below with reference to the drawings. In the first embodiment of the present invention, an endoscope for medical use will be exemplified as an example of the insertion instrument. Furthermore, the endoscope is assumed to be, for example, a so-called single-use endoscope that is disposed of after a single use.

[0018] FIG. 1 is an external perspective view showing a schematic configuration of an endoscope as an example of an insertion instrument according to a first embodiment of the present invention.

[0019] 1, the endoscope 1 is configured to include an insertion section 5 that is inserted into a subject, an operation section 6 provided on the base end side of the insertion section 5, a universal cord 7 that extends from the operation section 6, and an endoscope connector 8 provided on the end side of the universal cord 7. The insertion section 5 includes, in order from the tip side, a tip section 10, a bending section 11, and a flexible tube section 12.

[0020] As shown in Fig. 1, the tip portion 10 is disposed at the most distal end of the insertion section 5 of the endoscope 1, and is a structural unit that houses various structures therein, as will be described later. Here, Figs. 2 to 5 are views mainly showing the tip portion of the endoscope in Fig. 1. Of these, Fig. 2 is an external perspective view of the tip portion of the endoscope in Fig. 1. Fig. 3 is a front view of the tip portion as seen from the direction of arrow [3] in Fig. 2. Fig. 4 is a top view of the essential parts of the tip portion as seen from the direction of arrow [4] in Fig. 3. Fig. 5 is a cross-sectional view of the essential parts along the line [5]-[5] in Fig. 3.

[0021] 2, the tip portion 10 is made of a hard material and has a generally cylindrical shape. The tip portion 10 includes a tip portion body 10a, a tip cap 10b, a raising base 10c, and an insulating block 10z.

[0022] The tip body 10a is a basic component of the tip 10 and is made of a resin material such as PSU (polysulfone) resin. The tip body 10a has a flat portion 10aa, a tip side opening 10ab, and a lifting base housing portion 10ac.

[0023] The flat portion 10aa is a planar region formed on a part of the outer circumferential surface of the tip portion 10. The flat portion 10aa is provided with an illumination window 10d, an observation window 10e, and a nozzle 10f.

[0024] The illumination window 10d is configured by an optical member located at the forefront of the illumination optical system, which irradiates the subject with illumination light guided from a light source (not shown) by a light guide or the like.

[0025] The observation window 10e is part of the observation optical system of the imaging unit (not shown) provided at the tip portion 10. The observation window 10e is configured in such a way that the optical member located at the forefront of the observation optical system is disposed on the plane of the flat portion 10aa and exposed to the outside.

[0026] The observation optical system captures return light from the subject through the observation window 10e. The observation optical system then projects the captured return light onto the light-receiving surface of an imaging element (not shown) of the imaging unit. The imaging element then receives the return light and converts it into an imaging signal. The imaging element then captures an image of the subject. The optical axis of the observation optical system is set in a direction (side view direction) that intersects with the longitudinal axis O1 (see FIG. 1 ) of the insertion portion 5.

[0027] The nozzle 10f is connected to the distal end of an air / liquid supply tube 47 (see FIG. 18, etc.) described later, so that the nozzle 10f discharges the gas or liquid supplied from the air / liquid supply tube 47 onto the flat portion 10aa.

[0028] The distal end side opening 10ab is a portion that opens toward the outer circumferential side of the distal end portion 10. The distal end side opening 10ab communicates with a treatment instrument channel 31 (see FIG. 18, etc.) described later.

[0029] The elevator storage portion 10ac has a tip side opening 10ab as an opening, and is a portion in which the elevator 10c is stored so as to be able to freely protrude and retract.

[0030] The elevator 10c is a member for raising the distal end side of a treatment tool or the like (not shown; including a guide wire) protruding from the distal opening 31a (see FIG. 3) of the treatment tool channel 31, thereby changing the protruding direction from the distal end portion 10. For this purpose, the elevator 10c is disposed in the distal side opening 10ab at a position facing the distal opening 31a of the treatment tool channel 31. The elevator 10c is also attached so as to be able to swing freely relative to the distal end portion 10. Furthermore, the distal end side of an elevator operating wire 42 (see FIG. 18, etc.), which will be described later, is connected to the elevator 10c.

[0031] The elevator 10c has a concave surface 10ca (see FIG. 3) formed on the contact surface with which the side peripheral surface of the treatment tool or the like contacts when the elevator 10c is raised. The concave surface 10ca is formed to stably hold the treatment tool or the like while it is being raised by the elevator 10c.

[0032] The tip cap 10b is a member that covers and protects a portion of the outer surface of the tip body 10a. When attached to the tip body 10, the tip cap 10b is formed so as to expose the tip side opening 10ab and the area of ​​the flat portion 10aa where at least the illumination window 10d, the observation window 10e, and the nozzle 10f are disposed to the outside, and is formed so as to cover the rest of the outer surface of the tip body 10a.

[0033] The insulating block 10z is a component that is disposed between the treatment tool, etc. and the tip body 10a when the raising base 10c acts to raise the treatment tool, etc., and cuts off electrical conduction between the treatment tool, etc. and the tip body 10a.

[0034] That is, the insulating block 10z is disposed in a part of the distal end body 10a at a position facing one surface (treatment tool contact surface) of the elevator 10c in the raised state. In this case, the insulating block 10z has a treatment tool contact area in a substantially central area where the treatment tool or the like comes into contact.

[0035] In the endoscope 1 of this embodiment, the insulating block 10z is formed using the same material as the tip portion body 10a, for example, a resin member such as PSU (polysulfone) resin. In this case, the insulating block 10z is formed as a single component integral with the tip portion body 10a.

[0036] The insulating block 10z is also a component that prevents the treatment tool from moving beyond a predetermined maximum lifting range. That is, as the treatment tool is being raised by the raising base 10c, the treatment tool ultimately contacts the insulating block 10z. When the treatment tool is sandwiched between the raising base 10c and the insulating block 10z, the movement of the raising base 10c is prevented. This prevents the treatment tool from moving further in the lifting direction.

[0037] In general, in conventional endoscopes, the insulating block is made of a hard material such as ceramic, and the distal end body is made of a resin material. For example, in an endoscope disclosed in JP 2020-141904 A, the insulating block portion on the distal end body side against which the treatment tool or the like is pressed when the raising base acts to raise the treatment tool or the like is made of a material harder than the other portions of the distal end body to prevent damage such as scraping by the treatment tool or the like.

[0038] Furthermore, reusable endoscopes that can be repeatedly used after cleaning, etc., must be designed to be adaptable to a wide range of target cases and uses, etc. For example, the insulating block may be made of a harder material in consideration of durability or ease of assembly to the tip body.

[0039] However, using different materials for the insulating block and the other parts of the tip body results in higher manufacturing costs, which is particularly important for single-use endoscopes, which are designed for use in only one case.

[0040] Therefore, in the distal end portion 10 of the endoscope 1 of this embodiment, the distal end portion main body 10a and the insulating block 10z are formed as a single component from the same material, which has the effect of contributing to a significant reduction in manufacturing costs.

[0041] When raising the elevator 10c provided at the distal end portion 10 of the endoscope 1, a predetermined operation is performed using a predetermined operating member (an elevator operating lever 24 described later; see FIG. 18 ). By performing this raising operation, the elevator 10c can direct treatment tools (including medical treatment tools, guide wires, etc.) protruding forward from a distal end opening 31a (see FIG. 3 ) provided at the distal end portion 10 toward a site to be observed or treated. At this time, a predetermined operation is performed using the predetermined operating member (the elevator operating lever 24) to fix (lock) the position of the elevator 10c, thereby maintaining the treatment tools in the raised state.

[0042] In addition, the raising operation of the raising table 10c may be performed, for example, when a guide wire is used to secure an insertion path for a therapeutic treatment instrument prior to inserting the therapeutic treatment instrument from the duodenal papilla into the bile duct or pancreatic duct.

[0043] Generally, the guidewire is a long member with a much thinner diameter than the treatment instrument. On the other hand, the elevator has a contact surface of sufficient size to reliably raise the treatment instrument, and a concave portion is provided in the approximate center of the contact surface to ensure stability of the treatment instrument during elevation.

[0044] Here, the medical treatment tool has an outer diameter of a predetermined size, so that when the medical treatment tool is raised by the raising base, the medical treatment tool can be stably raised by fitting into the concave portion of the contact surface.

[0045] However, when using such a conventional elevator to raise an extremely thin guidewire, it was sometimes impossible to ensure sufficient locking force, particularly when attempting to guide the guidewire toward an object located above or to the left or right on the endoscope monitor screen (not shown).

[0046] In other words, when attempting to guide the guide wire toward an object located above or to the left or right on the endoscope monitor screen (not shown), the guide wire will be raised by abutting against the left and right side areas of the abutment surface of the raising stand.

[0047] Note that the left and right on the endoscope monitor screen refer to the left and right as viewed from the monitor screen. In this case, the left and right on the monitor screen correspond to the left and right as viewed from the base end of the distal end portion 10 of the endoscope 1 toward the distal end. Viewing the distal end from the base end of the distal end portion 10 refers to the line of sight in the direction indicated by arrow [V] in Fig. 2. Therefore, in Fig. 3, which is viewed from the direction of arrow [3] in Fig. 2, it is necessary to consider the left and right as being reversed.

[0048] As described above, a concave portion is formed in the approximate central region of the lifting platform, so that by placing a guide wire in this concave portion and lifting the lifting platform, even an extremely thin guide wire can be stably and easily guided toward the object in the center of the screen.

[0049] However, when the guide wire is raised by abutting it against the left and right side regions of the contact surface of the elevator, stable abutment of the guide wire is not ensured, and for example, the guide wire may come off the left and right side regions of the contact surface of the elevator. Here, as described above, the insulating block is disposed on the surface facing the elevator when it is raised. Therefore, the wire guide gets caught in the gap between the elevator and both left and right sides of the insulating block, and the wire guide cannot be clamped with sufficient force.

[0050] Therefore, in the distal end portion 10 of the endoscope 1 of this embodiment, the insulating block 10z is formed in the following shape: That is, as shown in Fig. 3, the insulating block 10z is formed to have a chamfered portion 10za and a gap protrusion portion 10zb.

[0051] The chamfered portion 10za is formed on the right side (closer to the outer surface of the tip portion 10) of the insulating block 10z when viewed from the direction of the arrow [V] in Fig. 2. As shown in Figs. 3 and 4, the chamfered portion 10za is formed in a region close to the right side of the insulating block 10z and is an inclined surface that slopes toward the base end.

[0052] By providing the insulating block 10z with the chamfered portion 10za, the guide wire that comes into contact with the raising base 10c and is raised can be guided to an area closer to the right side of the insulating block 10z.

[0053] When the guide wire is placed in this region, the side region of the elevator 10c pinches the guide wire and reliably presses against the chamfered portion 10za of the insulating block 10z, thereby increasing the locking force of the elevator 10c for the guide wire.

[0054] Specifically, for example, if an object (e.g., the duodenal papilla) is located in the upper right corner of the monitor screen, the guide wire can be guided in that direction, and when the state of the lifting table 10c at that time is locked, the guide wire can be securely held with sufficient locking force.

[0055] On the other hand, the gap protrusion 10zb is formed in the gap 10zc formed between the insulating block 10z and the tip body 10a in the left side region (near the center of the tip 10) of the insulating block 10z when viewed from the direction of the arrow [V] in Figure 2.

[0056] The gap protrusion portion 10zb extends in a direction approximately perpendicular to the formation direction of the gap 10zc (the extension direction of the treatment tool, etc. being raised) (see Figure 4), and is formed so as to protrude forward from the wall surface of the tip main body 10a (see Figure 5).

[0057] When the guide wire 102 (see FIG. 5 ) that is raised by contact with the elevator 10c is guided to a region near the left side of the insulating block 10z, the guide wire 102 enters the gap 10zc. At this time, the side region of the elevator 10c pinches the guide wire 102 and presses against the gap 10zc. However, depending on the respective sizes of the side region of the elevator 10c and the gap 10zc, the elevator 10c may not be able to pinch the guide wire 102 with sufficient force.

[0058] Therefore, in this embodiment, by providing gap protrusions 10zb at predetermined positions on the insulating block 10z, the side regions of the elevator 10c can clamp the guide wire 102 with sufficient force.

[0059] In this way, when the guide wire 102 is placed in the gap 10zc, the side regions of the elevator 10c sandwich the guide wire 102 and reliably press the gap protrusion 10zb of the insulating block 10z, thereby increasing the locking force of the elevator 10c for the guide wire 102.

[0060] Specifically, for example, if an object (e.g., the duodenal papilla) is located in the upper left of the monitor screen, the guide wire 102 can be guided in that direction, and when the state of the raising table 10c at that time is locked, the guide wire 102 can be securely held with sufficient locking force.

[0061] Next, as shown in Fig. 1, the bending section 11 is a tubular structural unit connected to the proximal end side of the tip section 10 in the insertion section 5 of the endoscope 1 and incorporating various structures therein. Here, Figs. 6 to 10 are views mainly showing the bending section of the endoscope in Fig. 1. Of these, Fig. 6 is a cross-sectional view taken along the longitudinal axis direction of the bending section of the endoscope in Fig. 1. Fig. 7 is a cross-sectional view taken along line [7]-[7] in Fig. 6. Fig. 8 is a schematic perspective view of the bending section in Fig. 6 as viewed from the proximal end side. Fig. 9 is a schematic perspective view showing only the elevator operation wire restricting member. Fig. 10 is a schematic perspective view showing a modified example of the elevator operation wire restricting member.

[0062] As shown in Fig. 6 etc., the bending section 11 is made up of a bending tube or the like, which is a tubular member made up of a plurality of bending pieces (11a, 11b, 11c). Of the plurality of bending pieces (11a, 11b, 11c), the bending piece arranged at the most distal end is called the distal piece 11a, and the bending piece arranged at the most proximal end is called the proximal piece 11c. The plurality of bending pieces arranged side by side between the distal piece 11a and the proximal piece 11c are called intermediate pieces 11b.

[0063] The bending pieces (11a, 11b, 11c) are arranged in a row along the longitudinal axis O1 of the insertion portion 5 (see FIGS. 1 and 6).

[0064] Adjacent pieces of each bending piece (11a, 11b, 11c) are rotatably connected to each other using rivets, etc. This allows the bending portion 11 to be bent in all directions, including up, down, left, and right directions of the insertion portion 5.

[0065] The distal ends of a pair of up-down bending operation wires 37 (two wires) and a pair of left-right bending operation wires 38 (two wires) are connected to the distal end piece 11a of the bending portion 11 (some wires are not shown in FIG. 6). The bending operation wires 37, 38 (four wires; see FIG. 7) are inserted through bending wire guides 103 that are arranged at predetermined positions on the inner circumferential surface of a bending tube made up of multiple bending pieces (11a, 11b, 11c). As a result, the bending operation wires 37, 38 are arranged within the bending portion 11 so as to maintain a direction along the longitudinal axis O1.

[0066] Here, the up, down, left, and right directions of the insertion portion 5 are defined, for example, as corresponding to the up, down, left, and right directions of the image captured by the imaging element (not shown) of the tip portion 10, among directions intersecting the longitudinal axis O1.

[0067] As described above, the bending wire guides 103 are disposed at predetermined positions on the inner circumferential surfaces of the plurality of bending pieces (11a, 11b, 11c). The bending wire guides 103 are disposed at positions spaced at intervals of approximately 90 degrees around the longitudinal axis O1 of the bending portion 11 (see FIG. 7).

[0068] The outer circumferential surface of the bending tube consisting of multiple bending pieces (11a, 11b, 11c) is covered with a tubular piece outer skin 104 (see Figures 6, 7, etc.). The outer surface of the bending portion 11 is further covered and protected by a tubular bending outer skin rubber 106 (see Figure 11), as will be described later.

[0069] As shown in Figures 6 to 8, the base end piece 11c of the multiple bending pieces (11a, 11b, 11c) has an elevator-operation wire restricting member 105. This elevator-operation wire restricting member 105 is a component provided to prevent an elevator-operation wire 42 (see Figures 11 to 13), which will be described later, from suddenly moving inside the bending portion 11 when the bending portion 11 performs a bending operation. The elevator-operation wire restricting member 105 will be described below.

[0070] First, before describing the elevator operating wire restricting member 105, the internal configuration of the bending portion 11 in the endoscope 1 of this embodiment will be briefly described below. Here, Fig. 11 is a view of the tip portion and bending portion of the endoscope in Fig. 1 as seen from above. Note that Fig. 11 is partially cut away to show the arrangement of the internal components of the bending portion. Fig. 12 is a cross-sectional view taken along line

[12] -

[12] in Fig. 11. Fig. 13 is a cross-sectional view taken along line

[13] -

[13] in Fig. 11.

[0071] As shown in Figures 11 to 13, various long internal components, such as an up-down bending operation wire 37, a left-right bending operation wire 38, a treatment instrument channel 31, an air / liquid supply tube 47, a light guide 107, an imaging signal cable 108, and a raising table operation wire 42, are inserted inside the bending portion 11.

[0072] The up-down bending operation wires 37 and the left-right bending operation wires 38 are provided in pairs, and are pulling wires that work in conjunction with the bending operation members (22, 23) and the endoscope bending operation mechanism 35 (both of which will be described later; see Figures 1, 18, 38, etc.) to realize the bending operation of the bending portion 11 in the up-down and left-right directions. The up-down bending operation wires 37 and the left-right bending operation wires 38 are arranged so as to be able to move forward and backward in the direction along the longitudinal axis O1 of the insertion portion 5 by bending wire guides 103 that are arranged at predetermined positions on the inner circumferential surfaces of the multiple bending pieces (11a, 11b, 11c).

[0073] The up / down bending operation wire 37 and the left / right bending operation wire 38 act to bend the bending section 11 by moving back and forth between the tip of the insertion section 5 and the operation section 6 in the direction along the longitudinal axis O1 of the insertion section 5.

[0074] The bending operation wires (37, 38) are composed of a wire core, an inner sheath 37b, and an outer sheath 37a (see FIG. 14 described later). The wire core is made of, for example, a stranded wire made of a metal wire member. The inner sheath 37b is, for example, a tubular member made of a resin member. The wire core is disposed inside the inner sheath 37b. The outer sheath 37a is, for example, a coiled tubular member formed by tightly winding a wire member made of a metal member or the like, and is formed to have flexibility as a whole. The inner sheath 37b, with the wire core inserted therethrough, is disposed inside the outer sheath 37a.

[0075] In the bending operation wire, the inner sheath 37 b and the outer sheath 37 a are disposed in the region from the flexible tube portion 12 to the base end piece 11 c of the bending portion 11 .

[0076] 14 shows only one of the bending operation wires, the up-down bending operation wire 37. Therefore, only the reference numerals 37a and 37b are used for the inner sheath and outer sheath. However, the configuration of the bending operation wire itself is the same as that of the left-right bending operation wire 38. As such, since not all of the multiple bending operation wires are necessarily shown in the drawings, in the following explanation, the reference numerals may be omitted when referring to the bending operation wires.

[0077] The treatment instrument channel 31 is a flexible tubular member disposed inside the insertion section 5 between the operation section 6 and the distal end section 10. The treatment instrument channel 31 is connected to a treatment instrument insertion mouthpiece 21 (described later; see FIGS. 1 and 18 ) of the operation section 6. This allows a treatment instrument or the like to be inserted through the treatment instrument insertion mouthpiece 21 and passed through the treatment instrument channel 31, so that the distal end portion of the treatment instrument or the like can be caused to protrude toward the distal end of the distal end section 10.

[0078] The air / liquid feed tube 47 is a tubular member connected to the air / liquid feed cylinder 45 (described later; see FIG. 18, etc.) The air / liquid feed tube 47 becomes a flow path through which gas or liquid flows when subjected to a predetermined operation.

[0079] The light guide 107 is a component that transmits illumination light from a light source device (not shown) to an illumination window 10d that constitutes part of the illumination optical system of the distal end portion 10. The light guide 107 passes through the inside of the endoscope connector 8, the universal cord 7, the operation section 6, and the insertion section 5, and reaches the illumination window 10d of the distal end portion 10.

[0080] The imaging signal cable 108 is a signal cable for transmitting control signals from a processor unit (control unit) (not shown) to the imaging element or image signals from the imaging element. The imaging signal cable 108 passes through the inside of the endoscope connector 8, the universal cord 7, the operation unit 6, and the insertion tube 5, and is inserted into the electric circuit board including the imaging element in the distal end portion 10.

[0081] The elevator operating wire 42 is a traction wire that operates in conjunction with the elevator operating lever 24 and the elevator operating mechanism 40 to perform operations such as raising the elevator 10c. The elevator operating wire 42 is composed of a wire core 42a, a sheath 43, and a guide coil 44. Of these, the wire core 42a is a traction wire made of, for example, a stranded wire made of a metal wire member. The sheath 43 is a flexible tubular member that covers the outer surface of the wire core 42a. The guide coil 44 is a tubular member that covers the outer surface of the sheath 43. The guide coil 44 is formed, for example, of a tightly wound coil or the like.

[0082] These internal components are not fixed to a fixed object inside the curved portion 11, but are arranged adjacent to each other with a slight gap between adjacent components.

[0083] With this configuration, the internal components are allowed to move radially relative to one another inside the bending portion 11. In particular, when the bending portion 11 is bent, each of the internal components is allowed to move radially within the gap space, so that the bending operation of the bending portion 11 can always be performed smoothly.

[0084] In general, in conventional endoscopes, the internal components inserted into the insertion section, including the bending section, are arranged to extend generally along the longitudinal axis of the insertion section, and the elevator control wire is arranged, for example, in a position offset to one side of the insertion section 5 (e.g., toward the R side).

[0085] For example, Fig. 72 is a diagram showing a cross section of a connection portion between a bending section and a flexible tube section in a conventional endoscope. Fig. 72 is a diagram corresponding to Fig. 15 of the endoscope of this embodiment, which will be described later. The configuration example shown in Fig. 72 is an example in which the elevator operating wire 42 is disposed eccentrically toward the R side of the insertion section 5.

[0086] In a conventional endoscope configured as described above, when the bending section is bent in a predetermined direction (e.g., upward (U direction) and rightward (R direction)), a compressive load is applied to the elevator control wire. The load on the elevator control wire gradually accumulates, but may be suddenly released at a predetermined timing. At this time, the elevator control wire is compressed inside the bending section, and as it buckles and releases, it moves suddenly from the R-side position to the L-side position, thereby releasing the accumulated load (a jump in bending phenomenon caused by a buckling phenomenon). The impact of this sudden movement causes the distal end portion 10 to bend as if it were jumping. At this time, the endoscopic image displayed on the monitor screen may be distorted, a phenomenon known as image jumping.

[0087] Therefore, in the endoscope 1 of this embodiment, a raising table operating wire restricting member 105 is provided at a predetermined position on the inner circumferential surface of the bending portion 11 .

[0088] 6 to 8, 11, 13, etc., the elevator operating wire restricting member 105 is disposed on the inner peripheral surface of the base end piece 11c of the bending tube of the bending portion 11, on the upper side of the positions where the pair of up-down bending operating wires 37 are disposed. Here, the upper side on the inner peripheral surface of the base end piece 11c refers to the surface in the direction of arrow U shown in FIG. 12, for example.

[0089] In this embodiment, the elevator operating wire 42 is arranged at a position offset in one direction (L side) in the internal region of the insertion section 5 on the proximal side up to the flexible tube section 12 (see FIGS. 11 and 12 ). On the other hand, in the internal region of the insertion section 5 on the distal side beyond the bending section 11, the elevator operating wire 42 is arranged at a position offset in the other direction (R side) (see FIGS. 11 and 13 ).

[0090] For this purpose, a raising-table operation wire restricting member 105 is provided on the base end piece 11c of the bending portion 11. Here, the raising-table operation wire restricting member 105 is joined to a predetermined portion on the inner peripheral surface of the base end piece 11c by, for example, laser welding or the like.

[0091] 9, the elevator operation wire restricting member 105 has a generally cylindrical shape with a spherical tip, and is formed with a through-hole 105a in a direction perpendicular to the column axis. This through-hole 105a is provided to prevent interference with the up / down bending operation wire 37. Here, the up / down bending operation wire 37 is inserted through the through-hole 105a.

[0092] With this configuration, the elevator operating wire restricting member 105 restricts the positioning of the elevator operating wire 42 to the L-side region inside the insertion section 5 in the area closer to the base end than the bending section 11 in the insertion section 5. At the same time, the elevator operating wire 42 restricts the positioning of the elevator operating wire 42 to the R-side region inside the insertion section 5 in the area closer to the tip end than the bending section 11 in the insertion section 5.

[0093] As a result, according to the endoscope 1 of this embodiment, the load applied to the elevator control wire 42 is reduced as the bending section 11 bends, preventing the elevator control wire 42 from moving suddenly, thereby suppressing display distortion of the endoscopic image and enabling endoscopic images of good image quality to be displayed at all times.

[0094] In addition to the form shown in Fig. 9, the elevator operation wire restricting member 105 may be configured as a modified form as shown in Fig. 10. The elevator operation wire restricting member 105A of the modified form shown in Fig. 10 is further formed to have a notched portion 105b and a flat portion 105c.

[0095] The notch 105b is provided to avoid interference between the elevator control wire regulating member 105A and the elevator control wire 42, while smoothly regulating the positioning of the elevator control wire 42 from the L side to the R side.

[0096] The flat surface 105c is a reference surface when the elevator operation wire restricting member 105A is welded to a predetermined portion of the base end piece 11c. The elevator operation wire restricting member 105A needs to be installed on the base end piece 11c so that the axial direction of the through hole 105a is approximately aligned with the longitudinal axis O1 of the bending portion 11.

[0097] Therefore, by welding and fixing the lifting platform operation wire restricting member 105A to the base end piece 11c while positioning the flat portion 105c so that it is parallel to a plane perpendicular to the longitudinal axis O1 of the curved portion 11, the lifting platform operation wire restricting member 105A can be installed at a specified position relative to the base end piece 11c.

[0098] The elevator-operating wire restricting member 105A of this modified example can also achieve the same effects as the first embodiment described above. Furthermore, according to this modified example, the notch 105b is provided, which allows for smoother positioning of the elevator-operating wire 42. Furthermore, according to this modified example, the flat portion 105c is provided, which allows for easy positioning of the elevator-operating wire restricting member 105A relative to the base end block 11c. This contributes to simplifying the assembly and manufacturing process.

[0099] 1, the flexible tube section 12 is a structural unit in the form of an elongated tube that is connected to the proximal end side of the bending section 11 in the insertion section 5 of the endoscope 1 and has various structures built in. The flexible tube section 12 is a tubular member that is configured to have flexibility according to the shape of the body cavity of the subject into which the insertion section 5 is inserted.

[0100] As shown in FIG. 14 and other figures, the flexible tube section 12 is composed of a flex 109 and a flexible tube outer jacket 110. The flex 109 is a spiral tube made of a flat plate material wound in a spiral shape, providing overall flexibility. The flex 109 is formed using a metal material such as stainless steel. The flexible tube outer jacket 110 is a tubular member formed of a so-called braided tube or the like, having a three-layer structure in which, from the inside, an inner resin layer, a braid layer, and an outer rubber jacket layer are laminated. Of these, the braid layer is formed of a metallic mesh tube. The inner resin layer is a tubular member that forms the core of the flexible tube outer jacket 110. The outer resin jacket layer is a tubular member formed to cover the outer surface of the blade. The configuration of the flexible tube section 12 itself is substantially the same as that applied to conventional endoscopes.

[0101] The endoscope 1 illustrated in this embodiment is a flexible endoscope equipped with a flexible tube portion 12, which is an example of an insertion device. However, the endoscope 1 of this embodiment is not limited to this configuration example, and may be, for example, a rigid endoscope equipped with a rigid tube portion.

[0102] As described above, in the insertion section 5 of the endoscope 1, the flexible tube section 12 is connected to the base end side of the bending section 11. In this case, in order to ensure the flexibility of the insertion section 5 as a whole, it is desirable to set the length in the longitudinal direction of the connection portion 12a (see FIG. 1) between the bending section 11 and the flexible tube section 12 as short as possible.

[0103] Therefore, in the endoscope 1 of this embodiment, the structure of the connecting portion 12a between the bending section 11 and the flexible tube section 12 is devised.

[0104] In the endoscope 1 of this embodiment, the connection portion 12a between the bending section 11 and the flexible tube section 12 is provided with a first ferrule 111, a second ferrule 112, and a ferrule ring 113, and is configured so that the connection between the bending section 11 and the flexible tube section 12 is made using a plurality of pins 114a and 114b. The configuration of the connection portion 12a between the bending section 11 and the flexible tube section 12 will be described in detail below. Here, FIGS. 14 to 17 are diagrams showing the configuration of the connection portion between the bending section and the flexible tube section of the endoscope. Of these, FIG. 14 is a cross-sectional view of the connection portion between the bending section and the flexible tube section of the endoscope in FIG. 1. FIG. 15 is a cross-sectional view taken along line

[15] -

[15] in FIG. 14. FIGS. 16 and 17 show the distal end side of the flexible tube section of the endoscope in FIG. 1, with FIG. 16 being an exploded perspective view. FIG. 17 is a schematic perspective view of the assembled state.

[0105] As shown in Figures 14 to 17, in the insertion section 5 of the endoscope 1, the connection portion 12a between the bending section 11 and the flexible tube section 12 is composed of a first mouthpiece 111, a second mouthpiece 112, and a mouthpiece ring 113.

[0106] The first base 111 is a connecting member formed in a substantially cylindrical shape. The first base 111 is formed using a metal member such as stainless steel. The flexible tube section 12 is connected to the base end side of the first base 111, and the bending section 11 is connected to the tip end side. Specifically, it is as follows.

[0107] At the base end side (flexible tube section 12 side) of the first mouthpiece 111, the tip end portion of the flex 109 of the flexible tube section 12 is fitted and held on the inner diameter side. Here, the first mouthpiece 111 and the flex 109 are fixed by welding (for example, laser welding).

[0108] On the base end side (flexible tube section 12 side) of the first connector 111, the distal end portion of the flexible tube outer jacket 110 of the flexible tube section 12 is held on the outer diameter side so as to cover the outer surface. Here, the first connector 111 and the flexible tube outer jacket 110 are fixed by adhesive.

[0109] Meanwhile, at the tip end side (the bending portion 11 side) of the first base 111, a base end piece 11c of the bending portion 11 is held on the outer edge portion on the inner diameter side. The first base 111 and the base end piece 11c are joined by a plurality of pins 114a (four; see FIG. 15 ). In this case, the pins 114a are fitted into holes 111a of the first base 111, and adhesive is applied around the pins 114a to adhesively fix them to the first base 111.

[0110] Furthermore, the second base 112 is held on the inner diameter side of the tip end side (curved portion 11 side) of the first base 111. The first base 111 and the second base 112 are joined together by a plurality of pins 114b (two pins; see FIG. 15 ). In this case, adhesive is applied around the pins 114b to adhere and fix them to the first base 111.

[0111] The second base 112 is a connecting member formed in a substantially cylindrical shape and is made of a metal material such as stainless steel.

[0112] The outer sheaths (37a; see FIG. 14) of the four bending operation wires 37, 38 are welded (for example, laser welded) to predetermined positions on the inner diameter side of the second base 112. The outer sheaths 37a and the inner sheaths 37b are bonded and fixed with an adhesive (see the portion indicated by the symbol [A] in FIG. 14).

[0113] The base ring 113 is a member formed in a substantially circular ring shape and is formed using a metal member such as stainless steel. The base ring 113 is disposed so as to cover the outer surface of the tip portion of the flexible tube outer jacket 110, which is disposed on the outer periphery of the base end side of the first base 111.

[0114] Here, the tip portion 110a of the flexible tube outer jacket 110 is in the form of a cut piece, as shown in Fig. 16. In this tip portion 110a, the mesh of the braid layer or the like tends to come loose and spread.

[0115] Therefore, the endoscope 1 of this embodiment is provided with a ferrule ring 113 to prevent the tip portion 110a of the flexible tube outer jacket 110 from expanding. By using this ferrule ring 113, it is possible to prevent the tip portion 110a of the flexible tube outer jacket 110, particularly the braid layer, from expanding, and to prevent the maximum outer diameter of the connection portion 12a from increasing.

[0116] At the same time, the mouth ring 113 can prevent the cut pieces of the blade layer from being exposed to the outside (see FIG. 17).

[0117] In addition, the configuration example shown in Figure 15 illustrates a configuration in which the elevator platform operation wire restricting member 105A exemplified in the above-mentioned modified example is used as the elevator platform operation wire restricting member provided on the base end piece 11c of the bending portion 11.

[0118] Next, as shown in FIG. 1 , the control section 6 is a box-shaped structural unit connected to the proximal end side of the flexible tube section 12 in the insertion section 5 of the endoscope 1 and incorporating various structures therein. Here, FIGS. 18 to 24 are diagrams showing the configuration of the control section of the endoscope in FIG. 1 . Of these, FIG. 18 is an exploded perspective view of the control section of the endoscope in FIG. 1 . FIG. 19 is a cross-sectional view showing the second housing side at the connection portion between the control section and the flexible tube section of the endoscope in FIG. 1 . FIG. 20 is a cross-sectional view taken along line

[20] -

[20] in FIG. 19 . FIG. 21 is a cross-sectional view showing the first housing side at the connection portion between the control section and the flexible tube section of the endoscope in FIG. 1 . FIG. 22 is a cross-sectional view taken along line

[22] -

[22] in FIG. 21 . FIG. 23 is an exploded perspective view of the housing at the connection portion between the control section and the flexible tube section of the endoscope in FIG. 1 . FIG. 24 is a cross-sectional view taken along line

[24] -

[24] in FIG. 19 .

[0119] As shown in FIGS. 1, 18, etc., the operating unit 6 has a housing 15 as the operating unit main body. The housing 15 is formed in a form divided into left and right halves by a first housing member 16 and a second housing member 17. These first and second housing members 16, 17 are formed, for example, by resin molding. As shown in FIGS. 20, 24, etc., the first housing member 16 and the second housing member 17 are joined together using, for example, a plurality of screws 116. For this purpose, for example, the first housing member 16 is formed with a plurality of through holes 16d through which the screws 116 are inserted. Furthermore, the second housing member 17 is formed with a plurality of screw holes 17a into which the screws 116 are threaded.

[0120] 20 and other figures, the screws 116 used to connect the first housing member 16 and the second housing member 17 only show two screws 116 at the connection between the operation section 6 and the flexible tube section 12. Although not shown, the first housing member 16 and the second housing member 17 are also joined by a plurality of other screws 116. With this configuration, the hollow housing 15 is formed.

[0121] Conventionally, the first housing member 16 and the second housing member 17 have been joined by, for example, disposing a ring-shaped member on the outer periphery and gluing, etc. With such conventional joining means, it has not been possible to reliably join the two members, the first housing member 16 and the second housing member 17, and there has been a tendency for, for example, rattle to occur.

[0122] Therefore, in the endoscope 1 of this embodiment, the first housing member 16 and the second housing member 17 are reliably joined together using a plurality of screws 116. With this configuration of this embodiment, rattles and the like do not occur when joining the first housing member 16 and the second housing member 17, ensuring a reliable joint and contributing to high precision of parts.

[0123] The housing 15 is formed with a grip 20 at approximately the center in the direction along the longitudinal axis O2 (see FIG. 1, etc.) for the surgeon to hold with his / her hand when using the endoscope 1. In addition, a treatment tool insertion mouthpiece 21 is attached to the housing 15 on the distal side of the grip 20.

[0124] In conventional endoscopes, the control section and the flexible tube section are connected by fitting the tip of the control section into one end of a cylindrical member and the base end of the flexible tube section into the other end of the cylindrical member, and then caulking the cylindrical member at the two fitting points. However, conventional connection methods require a lot of manufacturing man-hours, and further reductions in manufacturing costs are required.

[0125] Therefore, the innovations in the structure of the connecting portion between the control section 6 and the flexible tube section 12 in the endoscope 1 of this embodiment will be described in detail below. Here, Figures 25 to 27 are diagrams showing the structure of the connecting portion between the control section and the flexible tube section of the endoscope in Figure 1. Of these, Figure 25 is a cross-sectional view showing the connecting structure of the connecting portion between the control section and the flexible tube section of the endoscope in Figure 1. Figure 26 is a cross-sectional view taken along line

[26] -

[26] in Figure 25. Figure 27 is an exploded perspective view showing the rear end connecting member of the flexible tube section of the endoscope in Figure 1. Figure 28 is an enlarged cross-sectional view of the main part of the area indicated by

[28] in Figure 25.

[0126] The proximal end of the flexible tube section 12 is connected to the distal end of the housing 15 using a connecting member of a predetermined type. Here, the connecting member of the predetermined type is made up of a first connecting base 117 and a second connecting base 118.

[0127] The first connection base 117 and the second connection base 118 are, for example, both formed in a substantially cylindrical shape and formed as transparent resin molded parts that are optically transparent.

[0128] As shown in Figure 28, the first connection base 117 is roughly divided into a base region 117a, a tip region 117b, and an intermediate region 117c. The outer diameter d1 of the intermediate region 117c is slightly smaller than the outer diameter d2 of each of the base region 117a and the tip region 117b (d2 > d1). With this configuration, the intermediate region 117c is formed in a concave groove shape. Furthermore, the base region 117a and the tip region 117b are formed in a convex shape facing radially relative to the intermediate region 117c.

[0129] The base end region 117a of the first connection mouthpiece 117 engages with a groove (see reference numeral 17b in FIG. 28 ) formed on the inner diameter side of the housing 15. With the base end region 117a engaged with the groove 17b, the first housing member 16 and the second housing member 17 are mated and joined with screws. This allows the first connection mouthpiece 117 to be incorporated into the housing 15. In this state, movement of the first connection mouthpiece 117 in a direction along the longitudinal axis O1 of the insertion portion 5 is restricted.

[0130] Furthermore, the base end region 117a has a rotation stopper 117d formed at a predetermined position on the outer circumferential surface (see FIGS. 22, 26, etc.). This rotation stopper 117d engages with an engaged portion 17c formed on either the first housing member 16 or the second housing member 17 when the first connection base 117 is incorporated into the housing 15. This restricts rotation of the insertion portion 5 about the longitudinal axis O1 when the first connection base 117 is incorporated into the housing 15.

[0131] In this embodiment, the engaged portion 17c is formed on the second housing member 17 side.

[0132] The tip region 117b of the first connection base 117 is formed with a first step 117e and a second step 117f of different diameters on the inner peripheral side. The first step 117e is formed in a region closer to the tip, and the second step 117f is formed in a region axially more inward than the first step 117e. The inner diameter d3 of the first step 117e is formed slightly larger than the inner diameter d4 of the second step 117f (d3 > d4).

[0133] The outer surface of the end of the flexible tube outer jacket 110 of the flexible tube section 12 is adhesively fixed to the inside of the first step section 117e (see reference numeral 117x in FIG. 28). In this case, UV adhesive using an ultraviolet curing resin is used, for example.

[0134] The outer surface of the base end region 118a of the second connection base 118 is adhesively fixed to the inner diameter side of the second step portion 117f (see reference numeral 118x in FIG. 28). In this case, UV adhesive using an ultraviolet curable resin is used, for example.

[0135] The second connection cap 118 has a base end region 118a and a tip end region 118b. The outer diameter d5 of the base end region 118a is slightly larger than the outer diameter d6 of the tip end region 118b (d5 > d6). As described above, the inner surface of the second step 117f of the tip end region 117b of the first connection cap 117 is adhesively fixed to the outer surface of the base end region 118a.

[0136] Furthermore, the tip region 118b of the second connection base 118 is inserted into the inside of the end of the flex 109 of the flexible tube section 12. Then, the outer surface of the tip region 118b is adhesively fixed to the inner surface of the flex 109. In this case, for example, UV adhesive using an ultraviolet curing resin is used for the adhesive.

[0137] A substantially cylindrical anti-break member 115 is disposed at the connection portion where the distal end of the housing 15 and the proximal end of the flexible tube section 12 are connected. The anti-break member 115 is formed from a material such as silicone rubber.

[0138] The procedure for assembling the connection portion between the housing 15 and the flexible tube section 12 thus configured will be briefly described below.

[0139] First, the flexible tube section 12 is arranged by inserting the flex 109 inside the flexible tube outer jacket 110. After that, unnecessary portions of the end face of the flex 109 are cut off.

[0140] Next, the tip region 118b of the second connection base 118 is inserted into the inside of the cut end of the flex 109 and fixed with adhesive.

[0141] Next, adhesive is applied to the outer surface of the base end region 118a of the second connection socket 118, the outer surface of the end of the flex 109, and the outer surface of the end of the flexible tube outer jacket 110, and then the second connection socket 118 is inserted from the base end region 118a into the inner diameter side of the tip end region 117b of the first connection socket 117.

[0142] Then, the adhesive is hardened by irradiating the outer surface of the first connection base 117 with UV light, thereby adhesively fixing the first connection base 117 and the second connection base 118 together.

[0143] As described above, in the endoscope 1 of this embodiment, the connection portion between the flexible tube section 12 and the operation section 6 is fixed only by adhesive. Furthermore, with this configuration, for example, the second connection base 118 does not expose cut pieces formed on the cut end surface of the flex 109 to the outside. Furthermore, the outer surface of the cut end surface of the flex 109 is not exposed to the inside of the flexible tube section 12. Therefore, there is no need to worry about the cut pieces of the flex 109 damaging the internal structure of the flexible tube section 12 or other adverse effects, and safety can be easily ensured.

[0144] As shown in Figures 1, 18, etc., the treatment instrument insertion mouthpiece 21 is sandwiched between the first housing member 16 and the second housing member 17 and held by the assembled housing 15. The treatment instrument insertion mouthpiece 21 is formed as a part of a branch pipe 30 disposed inside the housing 15. Figures 29 and 30 are views showing a branch pipe provided in the operation section of the endoscope of Figure 1. Of these, Figure 29 is a cross-sectional view of the branch pipe provided in the operation section of the endoscope of Figure 1. Figure 30 is an external perspective view showing a part of the branch pipe of Figure 29.

[0145] The branch pipe 30 is composed of a channel coupler 32 and a channel mouthpiece 33 .

[0146] The channel coupler 32 has a first conduit 30a and a second conduit 30b. Of these, the first conduit 30a is a conduit extending along the longitudinal axis O2 of the housing 15 (operation unit 6). The second conduit 30b is a conduit formed by branching from the middle of the first conduit 30a in a direction intersecting with the longitudinal axis O2. A treatment tool insertion mouthpiece 21 is formed at the end of the second conduit 30b. A first suction tube 34 is connected to the end of the first conduit 30a.

[0147] The first suction tube 34 is inserted into the proximal end of the first conduit 30a and is adhesively fixed to the first conduit 30a, so that the first suction tube 34 communicates with the elevator housing 10ac and the distal end lateral opening 10ab of the distal end portion 10 through the channel mouthpiece 33 and the treatment instrument channel 31.

[0148] The endoscope 1 of this embodiment is assumed to be a single-use endoscope. Therefore, it does not require large-scale maintenance such as replacement of the treatment instrument channel 31 and the first suction tube 34. For this reason, the treatment instrument channel 31 and the first suction tube 34 are firmly fixed to the branch tube 30 by a simple structure using an adhesive.

[0149] In this case, UV bonding using an ultraviolet curing resin as an adhesive is applied to bond the branch pipe 30 to the treatment instrument channel 31 and the first suction tube 34. Bonding using an ultraviolet curing resin can be achieved by employing a branch pipe 30 molded from a transparent resin material having optical transparency, for example.

[0150] The channel mouthpiece 33 is a connecting member that connects the channel coupler 32 and the treatment instrument channel 31 .

[0151] The distal end of the channel coupler 32 is connected to the proximal end of the channel mouthpiece 33. In this case, the gaps between the channel mouthpiece 33 and the channel coupler 32 and between the channel mouthpiece 33 and the treatment instrument channel 31 are adhesively joined with an adhesive (see reference numeral 33a in FIG. 29), thereby ensuring watertightness at the adhesive portions.

[0152] The proximal end of the treatment instrument channel 31 is connected to the distal end of the channel mouthpiece 33. In this case, a hook-shaped portion 33a having a hook-shaped cross section is formed on the distal end of the channel mouthpiece 33. The outer surface of this hook-shaped portion 33a is formed with an inclined surface that slopes inward toward the distal end. The hook-shaped portion 33a is inserted into the inner diameter side of the proximal end of the treatment instrument channel 31.

[0153] At this time, the inclined surface of the hook-shaped portion 33a applies a force in the expanding direction to the inner diameter of the proximal end of the treatment instrument channel 31. This causes the treatment instrument channel 31 to be in close contact with the channel mouthpiece 33. Therefore, a watertight state is ensured at the connection portion.

[0154] Furthermore, at the connection portion between the treatment instrument channel 31 and the channel mouthpiece 33, a cable tie 119 is used to fasten and fix the connection portion from the outer surface of the treatment instrument channel 31. The cable tie 119 may be a commonly available general-purpose part.

[0155] In some conventional endoscopes, the branch tube 30 and the treatment instrument channel 31 are connected by fastening means, such as a tapered tube as a connecting member and a tightening nut, but such fastening means have the problem of being expensive to manufacture.

[0156] In addition, some conventional methods use adhesives or the like as fixing means, but when using adhesives for fixation, the adhesiveness can be poor depending on the material that forms the treatment instrument channel, and there is a problem that the number of processing steps increases, for example, after adhesion, a hardening process must be performed in a high-temperature furnace.

[0157] Therefore, in the endoscope 1 of this embodiment, the gaps between the channel mouthpiece 33 and the channel coupler 32 and the treatment instrument channel 31 are fixed with an adhesive, and at the same time, the hook-shaped portion 33a of the channel mouthpiece 33 is used to achieve a connection with improved adhesion to the treatment instrument channel 31. In addition to these, inexpensive and widely available cable ties 119 are used to fix from the outside.

[0158] With this configuration, according to this embodiment, the branch pipe 30 can be easily, reliably, and inexpensively connected to the treatment instrument channel 31. This can also contribute to improving assembly efficiency and reducing manufacturing costs.

[0159] In the housing 15 of the operating unit 6, on the proximal side of the grip 20, as shown in Figures 1, 18, etc., there are provided an up / down bending operation knob 22 and a left / right bending operation knob 23 as bending operation members, a raising platform operation lever 24, an air / liquid supply button 25, a suction button 26, and multiple button switches 27.

[0160] The up-down bending operation knob 22 and the left-right bending operation knob 23 are rotatably attached to the side of the first housing member 16, in a state where they are stacked in a direction along the same central axis O3. These up-down bending operation knob 22 and left-right bending operation knob 23, together with a pulley unit 36 ​​(see Figure 18, etc.) described later, constitute an endoscope bending operation mechanism 35 (hereinafter abbreviated as bending operation mechanism 35; see Figure 38, etc.).

[0161] The bending operation mechanism 35 pulls or loosens the up / down bending operation wire 37 and the left / right bending operation wire 38 in accordance with the amount of operation of the up / down bending operation knob 22 and the left / right bending operation knob 23. In this way, the bending operation mechanism 35 can bend the bending section 11 in all directions, including the up / down and left / right directions.

[0162] The elevator control lever 24 is rotatably attached to the side of the first housing member 16 between the up / down bending control knob 22 and the first housing member 16. This elevator control lever 24, together with a cylinder unit 41 (see FIG. 18, etc.), which will be described later, constitutes an elevator control mechanism 40 (see FIG. 61). The elevator control mechanism 40 pulls or loosens the elevator control wire 42 depending on the amount of operation of the elevator control lever 24. In this way, the elevator control mechanism 40 can swing the elevator 10c (see FIG. 2, etc.).

[0163] The air / liquid feed button 25 is an operation button for feeding air and liquid from the nozzle 10f to the flat portion 10aa of the tip portion 10. The air / liquid feed button 25 is attached to the housing 15 via a resin air / liquid feed cylinder 45. FIGS. 31 to 36 are views showing an air / liquid feed cylinder provided in the operation section of the endoscope of FIG. 1. Of these, FIG. 31 is a plan view, seen from the side, of the air / liquid feed cylinder provided in the operation section of the endoscope of FIG. 1. FIG. 32 is a view showing a tube fixing member of a first modified example. FIG. 33 is a view showing a tube fixing member of a second modified example. FIG. 34 is a view showing a tube fixing member of a third modified example. FIG. 35 is a view of the tube fixing member of the third modified example of FIG. 34 from a different direction. FIG. 36 is a view showing a tube fixing member of a fourth modified example.

[0164] As shown in FIG. 31, the air / liquid supply cylinder 45 has a cylinder body 45s, a first air supply port 45a, a first liquid supply port 45b, a second air supply port 45c, and a second liquid supply port 45d.

[0165] Cylinder body 45s has therein a piston (not shown) connected to air / liquid feed button 25. This piston moves back and forth inside cylinder body 45s depending on the pressure applied to air / liquid feed button 25. Depending on the position of the piston in cylinder body 45s, the piston establishes or blocks communication between first air feed port 45a and second air feed port 45c, and also establishes or blocks communication between first liquid feed port 45b and second liquid feed port 45d.

[0166] The proximal end of a first air supply tube 46a is connected to the first air supply port 45a. The first air supply tube 46a is fixed to the first air supply port 45a by adhesive while inserted into the first air supply port 45a.

[0167] The proximal end of a first liquid supply tube 46b is connected to the first liquid supply port 45b. The first liquid supply tube 46b is fixed to the first liquid supply port 45b by adhesive while inserted into the first liquid supply port 45b.

[0168] 18, the distal end portions of the first air supply tube 46a and the first liquid supply tube 46b are both connected to an air / liquid supply tube 47. The distal end of the air / liquid supply tube 47 is connected to the nozzle 10f of the distal end portion 10.

[0169] The distal end of a second air supply tube 46c is connected to the second air supply port 45c. The second air supply tube 46c is fixed to the second air supply port 45c by adhesive while inserted into the second air supply port 45c.

[0170] The distal end of a second liquid supply tube 46d is connected to the second liquid supply port 45d. The second liquid supply tube 46d is fixed to the second liquid supply port 45d by adhesive while inserted into the second liquid supply port 45d.

[0171] As described above, the endoscope 1 of this embodiment is designed to be a single-use endoscope. Therefore, it does not require extensive maintenance such as replacement of the air supply tubes and liquid supply tubes. For this reason, the tubes are firmly fixed to the air / liquid supply cylinder 45 with a simple adhesive.

[0172] In this case, it is desirable to use, for example, an ultraviolet curable resin as an adhesive for bonding the first air supply port 45 a to the first air supply tube 46 a, the first liquid supply port 45 b to the first liquid supply tube 46 b, the second air supply port 45 c to the second air supply tube 46 c, and the second liquid supply port 45 d to the second liquid supply tube 46 d. Adhesion using an ultraviolet curable resin can be achieved, for example, by employing an air / liquid supply cylinder 45 molded from a transparent resin material that is optically transparent.

[0173] In the endoscope 1 of this embodiment, these multiple air / liquid supply tubes have a complex conduit arrangement inside the operation unit 6. In particular, the second air supply tube 46c is arranged so as to extend in the opposite direction, at an angle of approximately 180 degrees, relative to the protruding direction of the second air supply port 45c, as shown in Fig. 31 .

[0174] As a result, the arrangement of multiple air and liquid supply tubes inside the operating section may change on various occasions, such as when operating the endoscope, during manufacturing and assembly of the endoscope, during transportation, or during long-term storage after shipment, and so-called kinks may occur, such as when the tubes become twisted, crushed, or broken.

[0175] Therefore, in the endoscope 1 of this embodiment, a coil member (not shown) is provided, for example, at the large bent portion of the second air supply tube 46c. In addition, the air / liquid supply cylinder 45 in the endoscope 1 of this embodiment is configured so that a tube fixing member 120 is provided on the side surface of the cylinder main body 45s, as shown in Figure 31.

[0176] This tube fixing member 120 is a member for holding the second air supply tube 46c at a predetermined midpoint. To this end, the tube fixing member 120 has a generally U-shaped cross section and is formed with a tube holding portion 120a that holds the second air supply tube 46c. In this case, the opening 120b of the tube holding portion 120a is formed with an opening width dimension that is generally equal to the outer diameter of the tube (46c) to be held.

[0177] The pipe fixing member 120 is fixed to the side surface of the cylinder body 45s by, for example, adhesive, such as an ultraviolet curable resin, and is therefore made of, for example, a transparent resin material that is optically transparent.

[0178] By adding this type of tube fixing member 120 to the cylinder body 45s, the second air supply tube 46c can be partially fixed securely and firmly, thereby preventing kinking of the tube.

[0179] In the illustrated configuration example, the tube fixing member 120 is shown as being configured to fix the second air supply tube 46c, but this is not limited to this example and can be applied in exactly the same way to other tubes.

[0180] The pipe fixing member 120 is not limited to the above-described configuration, i.e., the configuration in which the pipe fixing member 120 is formed separately from the cylinder body 45s and adhered to the side surface of the cylinder body 45s. For example, the pipe fixing member 120 may be formed integrally with the cylinder body 45s.

[0181] Furthermore, the shape of the tube fixing member 120 is not limited to the shape shown in FIG. 31, and various other shapes are possible.

[0182] For example, a tube fixing member 120A of a first modification shown in Figure 32 has a hook-shaped portion 120Ac in which the cross section of the tip of the tube holding portion 120Aa is formed into a hook shape. This hook-shaped portion 120Ac is formed so that an opening 120Ab, which is a gap between the tip of the hook-shaped portion 120Ac and the side surface of the cylinder body 45s, is approximately equal to or slightly smaller than the outer diameter of the tube (46c) to be held. Therefore, the tube holding portion 120Aa is formed with elasticity so as to be able to maintain a predetermined gap (the size of the opening 120Ab).

[0183] Therefore, when the tube (46c) is placed in the tube holding portion 120Aa, the opening 120Ab is widened to place the tube. When the force widening the opening 120Ab is released, the opening 120Ab returns to the predetermined gap.

[0184] By adopting such a configuration, the tube (46c) placed in the tube holding portion 120Aa is less likely to come out of the tube holding portion 120Aa. Therefore, the tube fixing member 120A of the first modified example can fix the tube (46c) more firmly.

[0185] 33 shows a second modified example of a tube fixing member 120B having a lid-shaped portion 120Bc formed in a lid shape so as to cover the gap between the tip of the tube holding portion 120Ba and the side surface of the cylinder body 45s. Therefore, the tube holding portion 120Ba is formed to have elasticity so that the lid-shaped portion 120Bc can be moved in a direction away from the side surface of the cylinder body 45s when the held tube (46c) is introduced into the tube holding portion 120Ba.

[0186] Therefore, when placing the tube (46c) in the tube holding portion 120Ba, the lid-shaped portion 120Bc is moved in a direction away from the side surface of the cylinder body 45s to place the tube. When the force spreading the lid-shaped portion 120Bc in the direction away from the side surface of the cylinder body 45s is released, the lid-shaped portion 120Bc returns to its original position.

[0187] By adopting such a configuration, the tube (46c) placed in the tube holding portion 120Ba is even less likely to come off the tube fixing member 120B. Therefore, the tube fixing member 120B of the second modified example can fix the tube (46c) even more firmly.

[0188] 34 shows a third modified example of a tube fixing member 120C, in which the tube holding portion 120a has a generally U-shaped cross section, similar to the first embodiment. This modified example differs in that a coil stopper 120Cd is provided on the side of the cylinder body 45s that faces the tube holding portion 120a.

[0189] The coil stopper 120Cd is a protrusion that is disposed at a position where it abuts against the end of the coil member 46ca provided on the outer surface of the second air supply tube 46c when the second air supply tube 46c is held by the tube holding portion 120a. With this configuration, it is possible to fix the second air supply tube 46c and simultaneously and easily set the length and position of the coil stopper 120Cd.

[0190] Furthermore, for example, the fourth modified tube fixing member 120D shown in Figure 36 is an example in which the tube holding portion attached to the cylinder body 45s is configured to be detachable, and multiple types of tube holding portions can be selectively attached.

[0191] The tube fixing member 120D includes a plurality of tube holding portions 120Da and 120Db having different shapes, and an attachment portion 120De that is fixed to the side surface of the cylinder main body 45s.

[0192] In the modified example shown in Figure 36, the multiple tube holding portions 120Da, 120Db are of the same type as those exemplified in the first and second modified examples, but this is not limited to this and other types can be applied.

[0193] The mounting portion 120De has a mounting opening 120Df. Correspondingly, each of the plurality of tube holding portions 120Da, 120Db has a mounting protrusion 120Dg formed therein. The mounting protrusion 120Dg fits into the mounting opening 120Df. This allows each of the tube holding portions 120Da, 120Db to be detachably attached to the mounting portion 120De.

[0194] With this configuration, the tube fixing member 120D of the fourth modification can selectively attach one of the multiple different types of tube holding parts 120Da, 120Db to the cylinder body 45s, allowing the appropriate tube holding part 120Da, 120Db to be selected depending on the tube to be held. In some cases, the air / liquid supply cylinder 45 can also be used without any tube holding part attached.

[0195] 1, 18, etc., the suction button 26 is an operation button for suctioning liquids, solids, etc. from a tip side opening 10ab (see FIG. 2) provided in the tip portion 10. This suction button 26 is attached to the housing 15 through a resin suction cylinder 48. Here, FIG. 37 is a cross-sectional view of the suction cylinder provided in the operation portion of the endoscope in FIG. 1.

[0196] 37 , the suction cylinder 48 has a first suction port 48a and a second suction port 48b. A piston (not shown) is provided inside the suction cylinder 48. The piston moves back and forth inside the suction cylinder 48 depending on the pressure applied to the suction button 26. The piston establishes or blocks communication between the first suction port 48a and the second suction port 48b depending on the position of the piston inside the suction cylinder 48.

[0197] The first suction port 48a is connected to the proximal end of the first suction tube 34. The first suction tube 34 is fixed to the first suction port 48a by adhesive while being inserted into the first suction port 48a.

[0198] The second suction port 48b is connected to the distal end of a second suction tube 49. The second suction tube 49 is fixed to the second suction port 48b by adhesive while inserted into the second suction port 48b.

[0199] The endoscope 1 of this embodiment is designed to be a single-use endoscope. Therefore, it does not require extensive maintenance such as replacing each suction tube. For this reason, each tube is firmly fixed to the suction cylinder 48 with a simple structure using adhesive.

[0200] In this case, it is desirable to use, for example, an ultraviolet curing resin as an adhesive for bonding the first suction port 48a to the first suction tube 34 and the second suction port 48b to the second suction tube 49. Bonding using an ultraviolet curing resin can be achieved, for example, by employing a suction cylinder 48 molded from a transparent resin material that is optically transparent.

[0201] 1, 18, etc., the plurality of button switches 27 are held in the housing 15 in a state where they are sandwiched between the first housing member 16 and the second housing member 17. Each button switch 27 can be assigned as a switch for activating various functions of the endoscope 1.

[0202] 1, the universal cord 7 extends from the base end side of the operation unit 6. Tubes such as a second air supply tube 46c, a second liquid supply tube 46d, and a second suction tube 49 are inserted inside the universal cord 7.

[0203] Various signal cables connected to the button switches and the imaging element of the imaging unit are inserted inside the universal cord 7. Furthermore, a light guide bundle and the like optically connected to the illumination optical system are inserted inside the universal cord 7.

[0204] 1, the endoscope connector 8 is connected to the extended end of the universal cord 7. This endoscope connector 8 can be connected to external devices (not shown) such as a light source device or a processor unit through a relay connector 9.

[0205] 1, the endoscope connector 8 of this embodiment has, for example, a substantially rectangular prism shape. The endoscope connector 8 has, for example, a liquid supply connector 8a connected to the second liquid supply tube 46d and a suction connector 8b connected to the second suction tube 49 on its side. The endoscope connector 8 also has, on its side, an engaging claw 8c that engages with the relay connector 9. The endoscope connector 8 also has, on its end face, an air supply plug that connects to the second air supply tube 46c, multiple electrical connectors that connect to various signal cables, and a light guide connector that connects to a light guide bundle (none of which are shown).

[0206] The relay connector 9 is a reusable item that can be used multiple times. That is, the relay connector 9 can be repeatedly used with multiple endoscopes (single-use endoscopes) 1. The relay connector 9 has, for example, a substantially cylindrical shape.

[0207] The relay connector 9 has a control board 9a therein. The control board 9a performs, for example, various signal processing on the imaging signal and correction processing of the power supply current supplied to the endoscope 1.

[0208] The relay connector 9 has a light source connector 9b and an air supply plug 9c on its tip end surface, and a plurality of electrical contacts 9d on its side surface.

[0209] The base end of the relay connector 9 is provided with a connector receiving hole 9e into which the endoscope connector 8 can be inserted. This connector receiving hole 9e has, for example, a substantially rectangular hole shape. The base end side of the light source connector 9b protrudes into the connector receiving hole 9e. The base end side of the light source connector 9b is positioned so that it can be optically connected to the light guide connector of the endoscope connector 8. Also, inside the connector receiving hole 9e, there are provided an air supply mouthpiece that connects to the air supply plug 9c and an electrical connector receptacle that connects to each electrical contact 9d (neither of which are shown). Of these, the air supply mouthpiece is positioned so that it can be connected to the air supply plug of the endoscope connector 8. Also, the electrical connector receptacle is positioned so that it can be connected to the electrical connector of the endoscope connector 8.

[0210] Next, the detailed configuration of the bending operation mechanism 35 in the endoscope 1 of this embodiment will be described below. Here, FIGS. 38 to 43 are views showing the bending operation mechanism provided in the operation section of the endoscope of FIG. 1. Of these, FIG. 38 is a cross-sectional view of the bending operation mechanism provided in the operation section of the endoscope of FIG. 1. In FIG. 38, the line

[16] -

[16] indicates the boundary of the first housing member 16, with the lower region in the figure being the internal region of the first housing member 16 and the upper region in the figure being the external region of the first housing member 16. FIG. 39 is an exploded perspective view showing the pulley unit in the bending operation mechanism of FIG. 38 from one end. FIG. 40 is an exploded perspective view showing the pulley unit in the bending operation mechanism of FIG. 38 from the other end. FIG. 41 is an enlarged perspective view of the first case member. FIG. 42 is a plan view schematically showing the state when the vertical bending pulley has rotated to the first rotation end position. FIG. 43 is a plan view schematically showing a state when the vertical bending pulley has rotated to the second rotation terminal position.

[0211] As described above, the bending operation mechanism 35 is mainly composed of the operation members of the up-down bending operation knob 22 and the left-right bending operation knob 23, and the pulley unit 36.

[0212] The up / down bending operation knob 22 is attached to the first housing member 16 through a shaft cylinder 16 a (see FIGS. 18 , 38 , etc.) protruding from the side of the first housing member 16 .

[0213] The left-right bending operation knob 23 is attached to the first housing member 16 by inserting a hollow shaft 92 (see FIG. 38) of a cover body 89, which will be described later, into the hollow shaft 81 of the up-down bending operation knob 22. The details of the attachment structure of each knob 22, 23 will be described later.

[0214] As shown in FIGS. 38 to 40, the pulley unit 36 ​​of the bending operation mechanism 35 has a vertical bending pulley 51 and a horizontal bending pulley 52 as rotating members, and a pulley case 53 as a holding member.

[0215] In the description of the bending operation mechanism 35 given below, the side from the up-down bending pulley 51 toward the left-right bending pulley 52 along the central axis O3 of the bending operation mechanism 35 will be referred to as one end (one side), and the side from the left-right bending pulley 52 toward the up-down bending pulley 51 along the central axis O3 of the bending operation mechanism 35 will be referred to as the other end (other side).

[0216] The vertical bending pulley 51 has a disk-shaped (drum-shaped) vertical bending pulley body 51a with a predetermined thickness. A keyhole 51b is provided in the center of the vertical bending pulley body 51a, penetrating in the direction of the central axis O3. A pair of pulley grooves 51c is provided on the outer periphery of the vertical bending pulley body 51a.

[0217] Wire fixing portions 51d are provided on both sides of the vertical bending pulley body 51a (both sides in the direction of the central axis O3 of the vertical bending pulley body 51a). Furthermore, connection grooves 51e are provided on both sides of the vertical bending pulley body 51a to connect the wire fixing portions 51d to the pulley grooves 51c.

[0218] The other side of the vertical bending pulley body 51a is provided with a protrusion 51f as an abutment. In this embodiment, the protrusion 51f has, for example, a partial arc shape and protrudes in the outer diameter direction of the vertical bending pulley body 51a (in the radial direction perpendicular to the central axis O3). The protrusion 51f is a projection that engages with an external component to restrict the rotation range.

[0219] The convex portion 51f is provided at a position in the circumferential direction of the vertical bending pulley body 51a (drum) where a wire fixing portion 51d (described later) is provided.

[0220] The vertical bending pulley 51 configured in this manner is configured to wind around the base ends of the pair of vertical bending operation wires 37. In this case, wire stators 37x attached to the base ends of the vertical bending operation wires 37 are inserted into the wire fixing portions 51d. This connects the vertical bending operation wires 37 to the vertical bending pulley 51. Then, the vertical bending operation wires 37 are guided to the pulley grooves 51c through the connecting grooves 51e.

[0221] The wire stator 37x is provided at one end of the wire (the base end of the up-down bending operation wire 37) and is an engaging part having a larger diameter than the other portion of the wire (up-down bending operation wire 37). The wire stator 37x is a fixed piece attached to one end side of the up-down bending operation wire 37.

[0222] As described above, the vertical bending pulley 51 includes a vertical bending pulley body 51a and a pair of pulley grooves 51c, and rotates around the central axis O3 in response to external operation. Here, the vertical bending pulley body 51a is a drum around which the pair of vertical bending operation wires 37 are wound at least once. In addition, the pair of pulley grooves 51c are flanges that prevent the pair of vertical bending operation wires 37 from falling off the vertical bending pulley body 51a.

[0223] The wire fixing portion 51d is a wire fixing portion that fixes the pair of up-down bending operation wires 37 to the up-down bending pulley body 51a. The wire fixing portion 51d as the wire fixing portion is provided on the flange (pulley groove 51c) or the drum (up-down bending pulley body 51a), and is a recess that is an engaging portion for the wire stator 37x (engaging part, fixing piece). The wire fixing portion 51d includes a structure that engages the engaging part (wire stator 37x).

[0224] A partial arc-shaped protective member 54 is attached to a portion of the outer periphery of the vertical bending pulley 51. This protective member 54 covers a portion of each pulley groove 51c, thereby preventing each vertical bending operation wire 37 from falling off from each pulley groove 51c.

[0225] The left-right bending pulley 52 has a left-right bending pulley body 52a that is disk-shaped (drum-shaped) and has a predetermined thickness. A keyhole 52b that penetrates the center of the left-right bending pulley body 52a in the direction of the central axis O3 is provided. A pair of pulley grooves 52c is provided on the outer periphery of the left-right bending pulley body 52a.

[0226] Wire fixing portions 52d are provided on both sides of the left-right bending pulley body 52a. Furthermore, connection grooves 52e are provided on both sides of the left-right bending pulley body 52a to connect the wire fixing portions 52d to the pulley grooves 52c.

[0227] Furthermore, a protrusion 52f is provided on one side of the left-right bending pulley body 52a as an abutment portion. In this embodiment, the protrusion 52f has, for example, a partial arc shape and protrudes in the outer diameter direction of the left-right bending pulley body 52a (in the radial direction perpendicular to the central axis O3). The protrusion 52f is a projection that engages with an external component to restrict the rotation range.

[0228] The convex portion 52f is provided in a position in the circumferential direction of the left / right bending pulley body 52a where a wire fixing portion 52d, which will be described later, is provided.

[0229] The left-right bending pulley 52 configured in this manner is configured to wind around the base ends of the pair of left-right bending operation wires 38. In this case, wire stators 38x attached to the base ends of the left-right bending operation wires 38 are inserted into each wire fixing portion 52d. This connects each left-right bending operation wire 38 to the left-right bending pulley 52. ​​Then, each left-right bending operation wire 38 is guided to each pulley groove 52c through each connection groove 52e.

[0230] The wire stator 38x is provided at one end of the wire (the base end of the left-right bending operation wire 38) and is an engaging part having a larger diameter than the other portions of the wire (left-right bending operation wire 38). The wire stator 38x is a fixing piece attached to one end of the left-right bending operation wire 38 by crimping (caulking).

[0231] As described above, the left-right bending pulley 52 includes a left-right bending pulley body 52a and a pair of pulley grooves 52c, and rotates around the central axis O3 in response to external operation. Here, the left-right bending pulley body 52a is a drum around which the pair of left-right bending operation wires 38 are wound at least once. In addition, the pair of pulley grooves 52c are flanges that prevent the pair of left-right bending operation wires 38 from falling off the left-right bending pulley body 52a.

[0232] The wire fixing portion 52d is a wire fixing portion that fixes the pair of left-right bending operation wires 38 to the left-right bending pulley body 52a. The wire fixing portion 52d as the wire fixing portion is provided on the flange (pulley groove 52c) drum (left-right bending pulley body 52a), and is a recess that is an engaging portion for the wire stator 38x (engaging part, fixing piece). The wire fixing portion 52d includes a structure that engages the engaging part (wire stator 38x).

[0233] A partial arc-shaped protective member 55 is attached to a portion of the outer periphery of the left-right bending pulley 52. ​​This protective member 55 covers a portion of each pulley groove 52c, thereby preventing each left-right bending operation wire 38 from falling off from each pulley groove 52c.

[0234] The pulley case 53 is a holding member that holds the pulley unit 36. The pulley case 53 has a case main body 60 (first holding member), and first and second case members 61 (second holding members) and 62 (third holding members) attached to both sides of the case main body 60.

[0235] As will be described in more detail later, the pulley case 53 (60, 61, 62) which is a retaining member has a plurality of grooves (65, 66, 69, 70) formed radially around the central axis O3, and stopper members 67, 68 which are plate members attached to the grooves and protrude in the direction in which the pulley unit 36 ​​is provided.

[0236] The case body 60 is made of a substantially cylindrical member. The inner diameter of the case body 60 is set to be larger than the outer diameters of the protection members 54 and 55 and smaller than the outer diameters of the arc-shaped protrusions 51 f and 52 f.

[0237] A partition wall 60a is provided inside the case body 60. This partition wall 60a divides the inside of the case body 60 into an up-down bending pulley chamber 63 and a left-right bending pulley chamber 64. Furthermore, a shaft hole 60b that penetrates in the direction of the central axis O3 is provided at the center of the partition wall 60a.

[0238] The depth (depth in the direction of the central axis O3) of the vertical bending pulley chamber 63 is set to be predetermined shallower than the thickness of the vertical bending pulley 51. As a result, the vertical bending pulley chamber 63 can accommodate the vertical bending pulley 51 with the convex portion 51f facing the other end surface of the case body 60.

[0239] The case body 60 is also provided with a pair of communication grooves 63a that connect the inside and outside of the vertical bending pulley chamber 63. These communication grooves 63a allow the vertical bending operation wire 37 wound around each pulley groove 51c of the vertical bending pulley 51 to extend outside the vertical bending pulley chamber 63.

[0240] Furthermore, a plurality of mounting portions 65 are provided on the other end surface of the case body 60 in the direction of the central axis O3. These mounting portions 65 are configured, for example, by slit-shaped recessed grooves. The mounting portions 65 are arranged radially from the central axis O3 of the case body 60 at a predetermined interval. For example, a flat metal stopper member 67 (see FIGS. 39 and 41) is detachably attached to each mounting portion 65.

[0241] At least one stopper member 67 is selectively attached to the group of mounting portions 65 arranged in this manner. In this embodiment, two stopper members 67 are selectively attached to the group of mounting portions 65. A portion of the stopper member 67 attached to the mounting portion 65 protrudes from the other end surface of the case main body 60. The protruding portion of the stopper member 67 comes into contact with the convex portion 51f of the vertical bending pulley 51.

[0242] As a result, each stopper member 67 regulates the rotation angle of the vertical bending pulley 51. That is, each stopper member 67 defines the rotation angle range of the vertical bending pulley 51 according to the position of the selectively attached mounting portion 65 (see, for example, FIGS. 42 and 43).

[0243] The depth (depth in the direction of the central axis O3) of the left-right bending pulley chamber 64 is set to be a predetermined value shallower than the thickness of the left-right bending pulley 52. ​​As a result, the left-right bending pulley chamber 64 can accommodate the left-right bending pulley 52 with the convex portion 52f facing one end surface of the case body 60.

[0244] The case body 60 is also provided with a pair of communication grooves 64a that communicate the inside and outside of the left-right bending pulley chamber 64. These communication grooves 64a allow the left-right bending operation wire 38 wound around each pulley groove 52c of the left-right bending pulley 52 to extend outside the left-right bending pulley chamber 64.

[0245] Furthermore, one end surface of the case body 60 in the direction of the central axis O3 is provided with a plurality of mounting portions 66. These mounting portions 66 are configured, for example, by slit-shaped recessed grooves. The mounting portions 66 are arranged radially from the central axis O3 of the case body 60 at a predetermined interval. For example, a flat metal stopper member 68 (see FIG. 39 ) is detachably attached to each mounting portion 66.

[0246] At least one stopper member 68 is selectively attached to the group of mounting portions 66 arranged in this manner. In this embodiment, two stopper members 68 are selectively attached to the group of mounting portions 66. A portion of the stopper member 68 attached to the mounting portion 66 protrudes from one end surface of the case main body 60. The protruding portion of the stopper member 68 comes into contact with the convex portion 52f of the left / right bending pulley 52.

[0247] As a result, each stopper member 68 restricts the rotation angle of the left / right bending pulley 52. ​​In other words, each stopper member 68 defines the rotation angle range of the left / right bending pulley 52 according to the position of the mounting portion 66 to which it is selectively attached.

[0248] The first case member 61 has a generally disk shape and an outer diameter that is generally the same as the outer diameter of the case main body 60. A shaft hole 61a is provided in the center of the first case member 61, penetrating in the direction of the central axis O3.

[0249] One end face of the first case member 61 (the face facing the other end face of the case body 60) is formed with a recess 61b to avoid interference with the protrusion 51f of the vertical bending pulley 51. Furthermore, one end face of the first case member 61 is provided with mounting portions 69 corresponding to the respective mounting portions 65 provided on the other end face of the case body 60.

[0250] The first case member 61 configured in this manner is fixed to the other end of the case body 60 by screws or the like. This fixation sandwiches the vertical bending pulley 51 between the first case member 61 and the case body 60. As a result, the vertical bending pulley 51 is held rotatably inside the vertical bending pulley chamber 63.

[0251] At this time, the stopper member 67 is held in a state where it is sandwiched between the mounting portion 65 and the mounting portion 69. To simplify the structure, it is possible to omit either the mounting portion 65 on the other end surface of the case main body 60 or the mounting portion 69 of the first case member 61.

[0252] A bracket 71 is integrally formed with the first case member 61. The bracket 71 has a generally rectangular plate shape that extends in the radially outer direction of the first case member 61.

[0253] The bracket 71 is provided with a groove-shaped guide portion 71a that guides a pair of up-down bending operation wires 37 extending from the up-down bending pulley chamber 63 and a pair of left-right bending operation wires 38 extending from the left-right bending pulley chamber 64.

[0254] The second case member 62 has a generally disk shape and an outer diameter that is generally the same as the outer diameter of the case main body 60. The second case member 62 has a central hole 62a that penetrates in the direction of the central axis O3.

[0255] The other end surface of the second case member 62 (the surface facing the one end surface of the case body 60) is formed with a recess 62b to avoid interference with the protrusion 52f of the left-right bending pulley 52. ​​Furthermore, the other end surface of the second case member 62 is provided with mounting portions 70 corresponding to the respective mounting portions 66 provided on the one end surface of the case body 60.

[0256] The second case member 62 configured in this manner is fixed to one end of the case body 60 by screws or the like. This fixation sandwiches the left-right bending pulley 52 between the second case member 62 and the case body 60. As a result, the left-right bending pulley 52 is held rotatably inside the left-right bending pulley chamber 64.

[0257] At this time, the stopper member 68 is held in a state where it is sandwiched between the mounting portion 66 and the mounting portion 70. To simplify the structure, it is possible to omit either the mounting portion 66 on the other end surface of the case main body 60 or the mounting portion 70 of the second case member 62.

[0258] The pulley unit 36 ​​configured in this manner is fixed to the inner surface of the first housing member 16 by screws or the like.

[0259] Specifically, the pulley unit 36 ​​is fixed to the first housing member 16 using, for example, some of the screws that fix the first case member 61 and the second case member 62 to the case body 60. The pulley unit 36 ​​is also fixed to the first housing member 16 by, for example, fastening a bracket 71 to the first housing member 16 with screws.

[0260] 40, a recess 71b is formed on the other end surface of the bracket 71. This recess 71b serves as a guide portion that guides the movement of a part (head member 97) of the raising platform operating mechanism 40 (see FIG. 61) (described in detail later).

[0261] Furthermore, in the pulley unit 36, in consideration of strength and the like, it is preferable that the bending pulleys 51, 52 be made of a resin material with good sliding properties, such as a material containing glass fiber. Specifically, for example, if POM (polyacetal) or the like is used for the bending pulleys 51, 52, a different type of material, such as a resin member of PC (polycarbonate) or ABS (acrylonitrile butadiene styrene), is used for the sliding parts, such as the pulley case 53 (60, 61, 62) and the bearing portion. Note that the combination of materials is not limited to this. For example, a configuration in which PC or ABS resin or the like is used for the bending pulleys 51, 52 and POM or the like is used for the pulley case 53 (60, 61, 62) may be used.

[0262] Here, the bending pulleys (51, 52) in the pulley unit 36 ​​will be described in more detail.

[0263] As described above, the pair of up-down bending operation wires 37 are wound around the up-down bending pulleys 51. In this case, first, the wire stators 37x at the base ends of the up-down bending operation wires 37 are inserted into the wire fixing portions 51d, and then the up-down bending operation wires 37 are guided to the pulley grooves 51c through the connecting grooves 51e.

[0264] Similarly, the left-right bending pulleys 52 respectively wind the pair of left-right bending operation wires 38. In this case, first, the wire stators 38x at the base ends of the left-right bending operation wires 38 are inserted into the wire fixing portions 52d, and then the left-right bending operation wires 38 are guided to the pulley grooves 52c through the connecting grooves 52e.

[0265] In this way, the bending wires (37, 38) guided to the pulley grooves 51c, 52c are wound around the outer peripheries of the pulley bodies (51a, 52a) of the bending pulleys (51, 52).

[0266] In this case, the outer peripheral shape of the pulley bodies (51a, 52a) in this embodiment is formed as shown in Fig. 44. Here, Fig. 44 and Fig. 45 are cross-sectional views showing the shapes of the pulley bodies (51a, 52a) of the up-down bending pulley 51 and the left-right bending pulley 52. ​​Of these, Fig. 44 shows the neutral state. Fig. 45 shows the state in which a predetermined amount of rotational force is applied from the neutral state of Fig. 44.

[0267] The shapes of the pulley bodies are substantially the same for the vertical bending pulley body 51a and the horizontal bending pulley body 52a. Specifically, in the vertical bending pulley 51, one end side (upward bending side) and the other end side (downward bending side) are in a mirror image relationship. Also, in the horizontal bending pulley 52, one end side (left bending side) and the other end side (right bending side) are in a mirror image relationship. In Figure 44, the reference numerals 51 and 51a are used to clearly indicate the vertical bending pulley 51 and the vertical bending pulley body 51a, but they can also be considered as the horizontal bending pulley 52 and the horizontal bending pulley body 52a.

[0268] 44, the cross-sectional shape of the wire winding portion of the vertical bending pulley body 51a, which is the wire winding drum portion of the vertical bending pulley 51, perpendicular to the central axis O3 is formed such that the radius r1 of the portion where the wire fixing portion 51d is provided (see reference numeral [A] in FIG. 44) is smaller than the radius r2 of the portion where the wire fixing portion 51d is not provided (see reference numeral [B] in FIG. 44) (r1>r2), resulting in a non-circular oval shape. Here, a non-circular oval shape refers to a non-circular shape including an arc, such as an egg shape, an ellipse shape, an oval shape, a rugby ball shape, a pear shape, or the like, and includes a shape including an arc or a parabolic shape, or a shape combining a semicircular portion and a parabolic portion.

[0269] In this case, the parabolic shape is defined as a shape that satisfies the following formula (1):

[0270] The parabola is a linear shape that is approximately equivalent to a parabola expressed by the following formula: y=ax^2 (a is a natural number; "^" is a symbol indicating exponentiation) (1)

[0271] In addition, in the cross section perpendicular to the central axis O3, the vertical bending pulley body 51a includes a region in the circumferential direction of the portion [B] where the wire fixing portion 51d is not provided, in which the region has a constant radius of 180 degrees (°) or more out of an angle of 360 degrees (°). Here, the radius of the region with a constant radius is, for example, about 6 mm to 7 mm.

[0272] In addition, in a neutral state where no rotational force is applied to the pulley (51), the wire (37) is wound around the outer circumferential surface of the vertical bending pulley body 51a for five-quarters (5 / 4) of a circumference (i.e., one circumference plus one-quarter of a circumference) of the vertical bending pulley body 51a.

[0273] Here, the neutral state in which no rotational force is applied to the pulley (51) refers to a state in which no operation is performed to apply tension to the bending operation wires (37, 38) from the bending operation knobs (22, 23).

[0274] Furthermore, the wire fixing portion 51d is provided at a position passing through the central axis O3 and along the longitudinal axis O2 when the pulley (51) is in a neutral state where no rotation is applied.

[0275] Furthermore, when the pulley (51) is in a neutral state where no rotation is being applied, the wire fixing portion 51d may be located at a position that does not pass through the central axis O3 and is not aligned with the longitudinal axis O2, and as an example, may be located on a line that intersects the longitudinal axis O2 at an angle of 90 degrees (°).

[0276] In each of the bending pulleys (51, 52) having such a configuration, for example, consider a case where a rotational force is applied to each of the bending pulleys (51, 52) from a neutral state (the state shown in FIG. 44) in which no rotational force is applied to each of the bending pulleys (51, 52), and each of the bending pulleys (51, 52) is rotated by an angle of approximately 90 degrees in the direction of arrow R1 in FIG. 44, resulting in the state shown in FIG. 45.

[0277] In this case, while each bending pulley (51, 52) is rotating, the position at which each wire (37, 38) is attached to the outer circumferential surface of each pulley body (51a, 52a) shifts within a small radius area, as shown in Figure 45.

[0278] Therefore, at this time, there is no increase in the rotation torque of the bending operation knobs (22, 23). In other words, bending operation can be performed with good operability while suppressing an increase in the operating force of the bending operation knobs (22, 23).

[0279] The same applies when the state of FIG. 45 is further rotated by an angle of approximately 90 degrees in the direction of the arrow R1.

[0280] Next, the bending operation member will be described below. First, the up / down bending operation knob will be described. Here, Figs. 46 to 49 are diagrams showing the configuration of the up / down bending operation knob. Of these, Fig. 46 is an exploded perspective view showing the up / down bending operation knob from one end side. Fig. 47 is an exploded perspective view showing the up / down bending operation knob from the other end side. Fig. 48 is a cross-sectional view of the main parts of the up / down bending operation knob when the brake is released. Fig. 49 is a cross-sectional view of the main parts of the up / down bending operation knob when the brake is applied.

[0281] 38 and 46 to 49, the up / down bending operation knob 22 is, for example, a bending operation knob integrated with a brake. That is, the up / down bending operation knob 22 has an integrally built-in brake mechanism that holds the rotation position of the up / down bending operation knob 22.

[0282] The up-down bending operation knob 22 has an operation knob body 75 , a friction rubber 76 , a push plate 77 , a cam plate 78 , a cover body 79 , a brake operation lever 80 , and a friction sheet 82 .

[0283] The operation knob body 75 is made of, for example, a resin molded product. The operation knob body 75 has a plurality of finger hooks 75a protruding radially. A brake chamber 75b is formed in the operation knob body 75 inside these finger hooks 75a. The brake chamber 75b has a generally cylindrical shape with one end in the direction of the central axis O3 open.

[0284] A hollow shaft 81 is integrally formed at the center of the operation knob body 75 (the center of the brake chamber 75b) and protrudes toward one end along the central axis O3.

[0285] A key 81a that can be fitted into the key hole 51b of the vertical bending pulley 51 is provided at one end of the hollow shaft 81. This key 81a has a shape in which, for example, a part of the outer periphery on the one end side of the hollow shaft 81 is cut out.

[0286] Furthermore, a weakened portion 81b is formed in the middle of the hollow shaft 81. The weakened portion 81b is formed, for example, by providing a groove on the outer periphery of the hollow shaft 81. Due to this weakened portion 81b, the torsional strength of the hollow shaft 81 is set to be weaker than the tensile strength of each of the up / down bending operation wires 37.

[0287] The friction rubber 76 is formed, for example, in an annular shape, and is accommodated in the brake chamber 75b through an annular friction sheet 82.

[0288] The push plate 77 is made of, for example, a resin molded product and has a substantially disk shape. The outer diameter of the push plate 77 is set to be substantially the same as the outer diameter of the friction rubber 76.

[0289] A plurality of cam followers 77a, each of which is made up of, for example, arc-shaped protrusions, are formed on one end surface of the push plate 77. These cam followers 77a are arranged in a ring shape on the one end surface of the push plate 77, centered on the central axis O3.

[0290] In this embodiment, an example of a configuration in which six cam followers 77a are formed is shown.

[0291] Generally, if at least three cam followers 77a are provided on the push plate 77, the push plate 77 can maintain a flat surface, so a minimum of three cam followers 77a is sufficient.

[0292] However, if the number of cam followers 77a is small, a large force applied to the push plate 77 may cause surface deformation of the push plate 77. If the push plate 77 is deformed in this way, a loss of force occurs, and therefore, it may become impossible to efficiently restrict the rotation of the bending operation knob.

[0293] Therefore, in this embodiment, the number of cam followers 77a is increased from the conventional configuration (three), for example, to six. By adopting such a configuration, the contact area of ​​the push plate 77 increases, making it possible to prevent the force loss of the push plate 77 from being reduced.

[0294] The number of cam followers 77a to be arranged is determined by the rotation angle of the brake operation lever 80. For example, when the rotation angle of the brake operation lever 80 is approximately 30 degrees, the cam plate 78 can be provided with, for example, approximately six cams 78a. Accordingly, six cam followers 77a are also provided.

[0295] A keyhole 77b is provided in the center of the push plate 77, penetrating the push plate 77 in the direction of the central axis O3.

[0296] Furthermore, the outer periphery of the push plate 77 is provided with a plurality of minute outward projections 77c that project in the radially outward direction.

[0297] The push plate 77 configured in this manner is housed in the brake chamber 75b with the other end surface abutting against the friction rubber 76.

[0298] The cam plate 78 is made of, for example, a resin molded product and has a substantially disk shape. The outer diameter of the cam plate 78 is set to be larger than the outer diameter of the push plate 77.

[0299] A plurality of cams 78a are formed on the other end surface of the cam plate 78 in the direction of the central axis O3. Each cam 78a is configured as a sloped protrusion whose protrusion amount toward the other end side gradually changes along the circumferential direction. These cams 78a are arranged in an annular shape on the other end surface of the cam plate 78 so as to face each cam follower 77a.

[0300] Further, a key hole 78b is provided in the center of the cam plate 78, penetrating the cam plate 78 in the direction of the central axis O3.

[0301] Furthermore, an annular flange 78c that protrudes toward the other end is formed on the outer edge of the cam plate 78. This flange 78c has an inner diameter that is larger than the outer diameter of the push plate 77.

[0302] The flange 78c has an inner periphery provided with a plurality of small inward projections 78d that project inwardly. These inward projections 78d are capable of engaging with the respective outward projections 77c provided on the push plate 77.

[0303] The cam plate 78 configured in this manner is housed in the brake chamber 75b with the push plate 77 housed inside the flange 78c.

[0304] The cover 79 is made of, for example, a resin molded product and has a substantially disk shape. The outer diameter of the cover 79 is set to be substantially the same as the inner diameter of the brake chamber 75b.

[0305] The lid body 79 is provided with a through-hole 79a that penetrates in the direction of the central axis O3 of the lid body 79. The lid body 79 is fixed to the operation knob body 75 with screws or the like while being housed in the brake chamber 75b.

[0306] The brake operation lever 80 is made of, for example, a resin molded product and has, for example, a substantially disk-shaped rotating plate 80a and a lever 80b that protrudes radially outward from the rotating plate 80a.

[0307] A through-hole 80c is provided in the center of the rotary plate 80a, penetrating the rotary plate 80a in the direction of the central axis O3.

[0308] An annular flange 80d is formed on the inner edge of the rotary plate 80a and protrudes toward the other end. The outer diameter of this flange 80d is set to be approximately the same as the inner diameter of the through-hole 79a of the lid 79. This flange 80d is slidably fitted into the through-hole 79a of the lid 79.

[0309] Furthermore, a key 80e protrudes from a part of the flange 80d, and can be fitted into the key hole 78b of the cam plate 78. By fitting this key 80e into the key hole 78b of the cam plate 78, the brake operating lever 80 can rotate integrally with the cam plate 78.

[0310] Here, in the up / down bending operation knob 22, the hollow shaft 81 passes through the centers of the friction sheet 82, friction rubber 76, push plate 77, cam plate 78, cover body 79, and brake operation lever 80, and protrudes to one end side beyond the brake operation lever 80.

[0311] As shown in Figures 38, 47, 48, and 49, the up and down bending operation knob 22 configured in this manner is attached to the first housing member 16 through a shaft tube 16a protruding from the side of the first housing member 16.

[0312] Specifically, the hollow shaft 81 of the up / down bending operation knob 22 is rotatably inserted into the shaft cylinder 16a, whereby the up / down bending operation knob 22 is rotatably supported relative to the first housing member 16.

[0313] In this case, a key 81a provided at one end of the hollow shaft 81 is fitted into a key hole 51b of the vertical bending pulley 51. This allows the vertical bending pulley 51 to rotate in conjunction with the rotation of the vertical bending operation knob 22. Then, depending on this rotation state, the vertical bending pulley 51 pulls or loosens the pair of vertical bending operation wires 37. This allows the vertical bending operation knob 22 to bend the bending section 11 in the vertical direction through the pulley unit 36.

[0314] If excessive operating force is applied to the vertical bending pulley 51 during such a bending operation, the fragile portion 81b of the hollow shaft 81 will break before each of the vertical bending operation wires 37 breaks. This makes it possible to prevent each of the vertical bending operation wires 37 from breaking.

[0315] A key 16b is provided on the protruding end of the barrel 16a protruding from the first housing member 16 (the other end of the barrel 16a in the direction of the central axis O3). The key 16b has, for example, a shape in which a portion of the outer periphery on the other end side of the barrel 16a is cut out. This key 16b passes through the brake operation lever 80, the cover 79, and the cam plate 78 and is keyed into a key hole 77b of the push plate 77. As a result, the push plate 77 is supported with its rotation restricted relative to the barrel 16a (first housing member 16).

[0316] When the cam plate 78 is rotated by operating the brake operation lever 80, the push plate 77 rotates relative to the cam plate 78. This relative rotation changes the contact position of the cam follower 77a with the cam 78a. This change in contact position displaces the push plate 77 toward the operation knob main body 75 (see the change from Figure 48 to Figure 49).

[0317] As a result, the friction rubber 76 is pressed against the friction sheet 82 and the operation knob main body 75 while being elastically deformed by the pressing force of the push plate 77. The pressing force of the push plate 77 generates strong frictional forces between the operation knob main body 75 and the friction sheet 82, and between the cam plate 78 and the cover body 79. Here, the push plate 77 is restricted from rotating with respect to the shaft cylinder 16a. This restricts the rotation of the operation knob main body 75. This restriction on rotation with respect to the operation knob main body 75 maintains the rotational position of the up / down bending operation knob 22 (the brake is activated).

[0318] Furthermore, if the rotational position of the up / down bending operation knob 22 is temporarily held and then the up / down bending operation knob 22 is forcibly rotated, the cam plate 78 will also rotate, reducing the pressing force of the push plate 77 and possibly reducing the frictional force. The inward protrusions 78d of the flange 78c engage with the outward protrusions 77c on the push plate 77, preventing the cam plate 78 from rotating. Therefore, even if the up / down bending operation knob 22, whose rotational position is held, is forcibly rotated, the rotation of the cam plate 78 is limited. As a result, the pressing force of the push plate 77 will not decrease, and neither will the frictional force.

[0319] Next, the left / right bending operation knob will be described. Here, Figs. 50 to 56 are diagrams showing the configuration of the left / right bending operation knob. Of these, Fig. 50 is an exploded perspective view showing the left / right bending operation knob from one end. Fig. 51 is an exploded perspective view showing the left / right bending operation knob from the other end. Fig. 52 is an exploded perspective view showing an enlarged view of a main part of the left / right bending operation knob from one end. Fig. 53 is an exploded perspective view showing an enlarged view of a main part of the left / right bending operation knob from the other end. Fig. 54 is an enlarged perspective view of a cam plate. Fig. 55 is a cross-sectional view of a main part of the left / right bending operation knob when the brake is released. Fig. 56 is a cross-sectional view of a main part of the left / right bending operation knob when the brake is applied.

[0320] 38 and 50 to 56, the left / right bending operation knob 23 is, for example, a brake-integrated bending operation knob. That is, the left / right bending operation knob 23 has an integrally built-in brake mechanism that holds the rotation position of the left / right bending operation knob 23.

[0321] The left / right bending operation knob 23 has an operation knob body 85 , a cam plate 86 , a push plate 87 , a friction rubber 88 , a cover body 89 , a brake operation knob 90 , a fixed shaft 91 , and a friction sheet 93 .

[0322] The operation knob body 85 is made of, for example, a resin molded product. The operation knob body 85 has a plurality of finger hooks 85a protruding radially. A brake chamber 85b is formed in the operation knob body 85 inside these finger hooks 85a. One end of the brake chamber 85b in the direction of the central axis O3 is open.

[0323] A through-hole 85c is provided in the center of the operation knob body 85, penetrating the operation knob body 85 in the direction of the central axis O3.

[0324] The cam plate 86 is made of, for example, a resin molded product. The cam plate 86 has a generally disk-like shape. A plurality of cams 86a are formed on one end surface of the cam plate 86 in the direction of the central axis O3. Each cam 86a is formed by a sloped protrusion whose protrusion amount toward one end gradually changes along the circumferential direction. These cams 86a are arranged in an annular shape centered on the central axis O3 on one end surface of the cam plate 86.

[0325] Furthermore, a through hole 86b is provided in the center of the cam plate 86, penetrating the cam plate 86 in the direction of the central axis O3. Furthermore, a key hole 86c is provided around the through hole 86b of the cam plate 86, penetrating the cam plate 86 in the direction of the central axis O3. Furthermore, an annular flange 86d is formed on the outer edge of the cam plate 86, protruding toward one end. The inner periphery of the flange 86d is provided with a plurality of small inward protrusions 86e that protrude in the inward radial direction. The cam plate 86 configured in this manner is housed in the brake chamber 85b.

[0326] The push plate 87 is made of, for example, a resin molded product and has a substantially disk shape. The outer diameter of the push plate 87 is set smaller than the inner diameter of the flange 86d of the cam plate 86.

[0327] A plurality of cam followers 87a, each consisting of, for example, an arc-shaped protrusion, are formed on the other end surface of the push plate 87. These cam followers 87a are arranged in a ring shape on the other end surface of the push plate 87 so as to face each of the cams 86a.

[0328] In this embodiment, five cam followers 87a are provided as a configuration example. The number of cam followers 87a is determined by the rotation angle of the brake operation knob 90. For example, the rotation angle of the brake operation knob 90 is approximately 60 degrees. Therefore, the maximum number of cams 86a that can be provided on the cam plate 86 is five. Accordingly, five cam followers 87a are also provided.

[0329] This configuration increases the contact area of ​​the push plate 87, which contributes to reducing the force loss of the push plate 87.

[0330] The push plate 87 has a keyhole 87b formed in the center thereof, which penetrates in the direction of the central axis O3 of the push plate 87. Furthermore, the outer periphery of the push plate 87 has a plurality of small outward protrusions 87c that protrude outward in the radial direction. These outward protrusions 87c are capable of engaging with the inward protrusions 86e formed on the cam plate 86. The push plate 87 thus configured is housed inside the flange 86d of the cam plate 86.

[0331] The friction rubber 88 is formed, for example, in an annular shape and is accommodated in the brake chamber 85b in a state in which the friction rubber 88 abuts against the push plate 87.

[0332] The cover 89 is made of, for example, a resin molded product and has a generally flat plate shape that is similar to the shape of the operation knob body 85 in a plan view.

[0333] A hollow shaft 92 that protrudes toward one end along the central axis O3 is integrally formed with the cover 89. A key 92a that can be fitted into the key hole 52b of the left-right bending pulley 52 is provided at one end of the hollow shaft 92. The key 92a has a shape in which, for example, a portion of the outer periphery of the hollow shaft 92 at one end is cut out.

[0334] The key 92a is set as a weak part that will plastically deform when a predetermined external force or more is applied. The twisting strength of the key 92a is set to be weaker than the tensile strength of each of the left and right bending operation wires 38.

[0335] The cover 89 is fixed to the operation knob body 85 by screws or the like while being in contact with one end of the operation knob body 85. In this case, a friction rubber 88 is in contact with the cover 89 through an annular friction sheet 93.

[0336] The brake operation knob 90 is an operation member for maintaining the rotational state (rotational position) of the left / right bending operation knob 23 by restricting the rotation of the left / right bending operation knob 23 .

[0337] The brake operation knob 90 is made of, for example, a resin molded product and has a rotating member 90a having a gentle, generally truncated cone shape and a knob 90b protruding from the other end of the rotating member 90a.

[0338] A through-hole 90c that passes through the rotating member 90a and the knob 90b in the direction of the central axis O3 is provided in the center of the brake operation knob 90. A key 90d that can be fitted into a key hole 86c of the cam plate 86 protrudes from one end face of the rotating member 90a.

[0339] The rotating member 90a of the brake operation knob 90 is rotatably abutted against the other end of the operation knob body 85. In this state, the key 90d of the brake operation knob 90 passes through a through hole 85c of the operation knob body 85 and is key-fitted into a key hole 86c of the cam plate 86. This allows the brake operation knob 90 to rotate integrally with the cam plate 86.

[0340] The fixed shaft 91 is made of, for example, a machined metal part. A key 91a that can be fitted into a key hole 87b of the push plate 87 is provided midway on the fixed shaft 91. The fixed shaft 91 passes through the centers of the brake operation knob 90, operation knob body 85, cam plate 86, push plate 87, friction rubber 88, and friction sheet 93, and is inserted into the hollow shaft 92. In this case, the key 91a of the fixed shaft 91 is key-fitted into the key hole 87b of the push plate 87.

[0341] As shown in FIG. 38 , the left / right bending operation knob 23 configured in this manner is attached to the first housing member 16 by inserting the hollow shaft 92 of the left / right bending operation knob 23 into the hollow shaft 81 of the up / down bending operation knob 22.

[0342] In this case, a key 92a provided at one end of the hollow shaft 92 is fitted into a key hole 52b of the left-right bending pulley 52. ​​This allows the left-right bending pulley 52 to rotate in conjunction with the rotation of the left-right bending operation knob 23. Depending on this rotation state, the left-right bending pulley 52 pulls or loosens the pair of left-right bending operation wires 38. This allows the left-right bending operation knob 23 to bend the bending section 11 in the left-right direction through the pulley unit 36.

[0343] If excessive force is applied to the left / right bending operation knob 23 during such bending operation, the key 92a of the hollow shaft 92 will break before each left / right bending operation wire 38 breaks, thereby preventing each left / right bending operation wire 38 from breaking.

[0344] 38, one end of the fixed shaft 91 inserted into the hollow shaft 92 is connected in a state in which its rotation is restricted to the shaft hole 62a of the second case member 62. As a result, the push plate 87 is supported in a state in which its rotation is restricted to the shaft cylinder 16a (first housing member 16).

[0345] When the cam plate 86 is rotated by operating the brake operating knob 90, the push plate 87 rotates relative to the cam plate 86. This relative rotation changes the contact position of the cam follower 87a with the cam 86a. This change in contact position displaces the push plate 87 toward the cover 89 (see the change from Figure 55 to Figure 56).

[0346] As a result, the friction rubber 88 is pressed against the friction sheet 93 and the cover 89 while being elastically deformed by the pressing force of the push plate 87. The pressing force of the push plate 87 generates a strong frictional force between the cover 89 and the friction sheet 93, and between the cam plate 86 and the operating knob body 85. Here, the push plate 87 is restricted from rotating relative to the fixed shaft 91.

[0347] Furthermore, the cover body 89 is fixed and rotationally restricted with respect to the operation knob body 85. These restrict the rotation of the operation knob body 85. This restriction on rotation with respect to the operation knob body 85 maintains the rotational position of the left / right bending operation knob 23.

[0348] Furthermore, if the rotational position of the left / right bending operation knob 23 is temporarily held and then the left / right bending operation knob 23 is forcibly rotated, the cam plate 86 will also rotate, reducing the pressing force of the push plate 87 and possibly reducing the frictional force. The inward protrusions 86e of the flange 86d engage with the outward protrusions 87c provided on the push plate 87, preventing the cam plate 86 from rotating. Therefore, even if the left / right bending operation knob 23, whose rotational position is held, is forcibly rotated, the rotation of the cam plate 86 is limited. As a result, the pressing force of the push plate 87 will not decrease, and the frictional force will not decrease either.

[0349] As described above, the up / down bending operation knob 22 is attached to the first housing member 16 through the shaft tube 16a of the first housing member 16 (see FIG. 38, etc.). In this state, the up / down bending operation knob 22 is rotatable around the shaft tube 16a as a support shaft.

[0350] In this case, in the conventional configuration, a part of the operation knob body 75 of the up-and-down bending operation knob 22 (a part of the ceiling portion in the brake chamber 75b) is in contact with a part (top) of the shaft tube 16a of the first housing member 16. Therefore, in the conventional configuration, when the operation knob body 75 rotates, a part of the operation knob body 75 and a part of the shaft tube 16a slide against each other.

[0351] Here, both the operation knob main body 75 and the first housing member 16 are made of a resin material such as polycarbonate (PC). Therefore, when the two members (75, 16a) slide, they may scrape against each other, generating powdery dust. If powdery dust or the like is generated at the sliding portion, the operation knob main body 75 may not be able to rotate smoothly, which may increase the bending operation force. This results in a problem of reduced operability of the up / down bending operation knob 22.

[0352] Therefore, in this embodiment, a UD spacer 121 is provided at the sliding portion between the operation knob main body 75 and the first housing member 16. Here, Fig. 57 is an enlarged cross-sectional view of the cross section of Fig. 38 showing the vicinity of the sliding portion between the operation knob main body (up / down bending operation knob) and the shaft tube (first housing member). That is, Fig. 57 is an enlarged cross-sectional view of the area indicated by

[56] in Fig. 38. Also, Fig. 58 is an external perspective view showing only the UD spacer.

[0353] The UD spacer 121 is a thin sheet-like member formed in a circular ring shape. The UD spacer 121 is made of a resin member with slidability, such as PTFE (polytetrafluoroethylene). The UD spacer 121 having such a configuration is disposed in a position sandwiched between the operation knob main body 75 and the first housing member 16.

[0354] With this configuration in this embodiment, the operation knob main body 75 and the first housing member 16 do not slide directly against each other, but slide through the UD spacer 121, which has high slidability. This improves the slidability between the two (75, 16a), preventing the generation of powdery dust and ensuring smoother rotation of the operation knob main body 75. This contributes to improving the operability of the up / down bending operation knob 22.

[0355] In addition, in an endoscope having a conventional configuration, when the brake operation knob 90 is rotated, the left / right bending operation knob 23 may also rotate at the same time as the brake operation knob 90 is rotated.

[0356] That is, when the brake operating knob 90 is rotated in a predetermined manner, the cam plate 86 rotates due to the mechanism and action described above, and the push plate 87 is pushed down. At this time, the key 91 a of the fixed shaft 91 is key-fitted into the key hole 87 b of the push plate 87, so the rotation of the push plate 87 relative to the fixed shaft 91 is restricted.

[0357] In this case, if the key fitting between the push plate 87 and the fixed shaft 91 is strong, when the push plate 87 is pushed down, a force acts to push down the fixed shaft 91 in the same direction.

[0358] In an endoscope with a conventional configuration, the fixed shaft 91 is inserted into a hollow shaft 92 of the cover 89 of the left-right bending operation knob 23. The fixed shaft 91 is connected in a state in which its rotation is restricted to the shaft hole 62a of the second case member 62 included in the pulley case 53. On the other hand, the fixed shaft 91 is allowed to move slightly within the hollow shaft 92 in a direction along the central axis O3.

[0359] Specifically, for example, when the fixed shaft 91 is inserted into the hollow shaft 92 and the brake operating knob 90 is in an unloaded state (non-rotating operating state), a step provided on the outer periphery of the fixed shaft 91 abuts against a step provided on the inner periphery of the hollow shaft 92, thereby restricting movement of the fixed shaft 91 in the direction along the central axis O3 within the hollow shaft 92.

[0360] However, if there is a gap between the step of the fixed shaft 91 and the step of the hollow shaft 92, movement in the direction along the central axis O3 will be allowed by the amount of that gap.

[0361] When the fixed shaft 91 is pressed down in this manner, the brake operation knob 90 is pressed downward (downward in the direction along the central axis O3) while being rotated. Then, the rotating member 90a of the brake operation knob 90 is pressed against the upper surface of the operation knob body 85 of the left / right bending operation knob 23, rotating the operation knob body 85. As a result, when the brake operation knob 90 is rotated, the left / right bending operation knob 23 may also rotate at the same time.

[0362] Therefore, in this embodiment, an RL spacer 122 is provided to restrict movement of the fixed shaft 91 in the direction along the central axis O3 within the hollow shaft 92. Here, Fig. 57 shows the vicinity of the abutment portion between the fixed shaft and the hollow shaft in the left / right bending operation knob in addition to the above-mentioned predetermined portion in the cross section of Fig. 38. Also, Fig. 59 is an external perspective view showing only the RL spacer.

[0363] The RL spacer 122 is formed in an annular shape and is a component provided to fill a predetermined gap between the fixed shaft 91 and the hollow shaft 92. Specifically, as shown in Figure 57, the RL spacer 122 is disposed in the gap that exists between the step portion of the fixed shaft 91 and the step portion of the hollow shaft 92.

[0364] With this configuration, according to the configuration of this embodiment, by providing an RL spacer 122 that fills the gap between the fixed shaft 91 and the hollow shaft 92, it is possible to prevent the left / right bending operation knob 23 from rotating when the brake operation knob 90 is rotated, thereby contributing to improved operability.

[0365] Furthermore, the brake mechanism of the left / right bending operation knob 23 operates, for example, as follows. First, when the brake operation knob 90 is rotated, the cam plate 86 rotates in conjunction with the rotation. When the cam plate 86 rotates, the multiple cams 86a act on the multiple cam followers 87a of the push plate 87, moving the push plate 87 in a direction pushing down in the direction along the central axis O3. The push plate 87 then presses and compresses the friction rubber 88. The friction rubber 88 then presses the cover 89 downward in the direction along the central axis O3 through the push plate 87. This restricts the rotation of the cover 89, and therefore the rotation of the left / right bending operation knob 23.

[0366] On the other hand, the brake mechanism of the up / down bending operation knob 22 operates, for example, as follows. First, when the brake operation lever 80 is rotated, the cam plate 78 rotates in conjunction with the rotation. When the cam plate 78 rotates, the multiple cams 78a act on the multiple cam followers 77a of the push plate 77, moving the push plate 77 in a direction pushing up along the central axis O3. Then, the push plate 77 presses and compresses the friction rubber 76 in a direction along the central axis O3. Then, the friction rubber 76 presses the operation knob main body 75 (upward) along the central axis O3 through the push plate 77. This restricts the rotation of the operation knob main body 75, and therefore the rotation of the up / down bending operation knob 22.

[0367] In this case, when the brake mechanisms of the up / down bending operation knob 22 and the left / right bending operation knob 23 act, the rotation of the cam plates 86, 78 causes the cams 80a, 78a to abut and slide against the cam followers 87a, 77a formed on the push plates 87, 77. The sliding positions correspond to the areas indicated by the symbols [RL] and [UD] in Fig. 59. Fig. 59 is an enlarged cross-sectional view of the cross section of Fig. 38, showing the sliding portions of the cam plate and the push plate. That is, Fig. 59 is an enlarged cross-sectional view of the area indicated by

[59] in Fig. 38.

[0368] In conventional endoscopes, the cam plate and the push plate are generally made of, for example, POM (polyacetal) resin, etc. If the sliding parts are made of the same material, this can cause abnormal noises and the like to occur during sliding.

[0369] Therefore, in the endoscope 1 of this embodiment, for example, the push plates 87 and 77 are made of a material different from that of the cam plates 86 and 78 .

[0370] Specifically, for example, when a POM (polyacetal) resin member is used for the push plates 87, 77, a PC (polycarbonate) resin member is used for the cam plates 86, 78, for example.

[0371] In this way, by using different materials for the push plates 87, 77 and the cam plates 86, 78, it is possible to prevent the generation of abnormal noises during sliding.

[0372] In this embodiment, the push plates 87, 77 and the cam plates 86, 78 are made of the above-described combination of materials, but the present invention is not limited to this configuration example. However, it is desirable to take into consideration the materials of the components adjacent to the push plates 87, 77 and the cam plates 86, 78. Furthermore, the selection of the materials themselves is not limited to the above-described examples.

[0373] Next, the configuration of the elevator operating mechanism 40 will be described in detail. Here, Fig. 61 is a perspective view showing the elevator operating mechanism of the endoscope in Fig. 1. Fig. 62 is a cross-sectional view of the main part of the cylinder unit of the elevator operating mechanism in Fig. 61.

[0374] 61 and 62, the cylinder unit 41 of the elevator operating mechanism 40 has a cylinder 95 through which the base end of the elevator operating wire 42 can be inserted. A rod 96 is inserted into the base end of this cylinder 95 so as to be movable back and forth.

[0375] The base end of the elevator control wire 42 is connected to this rod 96. Specifically, the base end side of the elevator control wire 42 is inserted into the cylinder 95 from the tip side of the cylinder 95. Inside the cylinder 95, the base end of the elevator control wire 42 is exposed from the sheath 43. The base end of the elevator control wire 42 exposed from the sheath 43 is connected to the rod 96.

[0376] Outside the cylinder 95, a head member 97 is connected to the base end of the rod 96. The head member 97 is slidable relative to a recess 71b (see FIG. 40) provided in the bracket 71. As a result, the head member 97 is guided by the recess 71b and is movable along the longitudinal axis O2 of the housing 15.

[0377] A communication hole 95a that connects the inside and outside of the cylinder 95 is provided on the side of the tip end of the cylinder 95. The base end side of the guide coil 44 that covers the sheath 43 of the elevator operating wire 42 is inserted into the cylinder 95 near the communication hole 95a. An adhesive is injected into the inside of the cylinder 95 from the communication hole 95a, so that the guide coil 44 and the sheath 43 are adhesively fixed to the inner circumferential surface of the cylinder 95.

[0378] The elevator operating lever 24 has a circular, plate-shaped rotating cam 24a and a lever 24b that protrudes radially outward from the rotating cam 24a. The rotating cam 24a and the lever 24b are integrally formed by, for example, resin molding.

[0379] 18, the rotating cam 24a is disposed between the up / down bending operation knob 22 and the first housing member 16. The shaft cylinder 16a is inserted into the rotating cam 24a, so that the elevator operation lever 24 is rotatably supported by the first housing member 16.

[0380] Here, the rotating cam 24a is provided with a cam pin 24c (see FIG. 61) that protrudes toward the first housing member 16. This cam pin 24c is inserted into an arc-shaped key hole 16c (see FIG. 18) provided in the first housing member 16.

[0381] The rotation of the elevator operating lever 24 is limited, for example, within an angular range in which the lever 24b abuts against two protrusions formed on the first housing member 16. The rotation of the elevator operating lever 24 can also be limited within an angular range in which the cam pin 24c moves from one end of the keyhole 16c to the other end.

[0382] Additionally, inside the first housing member 16, the cam pin 24c is connected to the head member 97 of the cylinder unit 41 through a relay member 98. This causes the rod 96 to move back and forth within the cylinder 95 in conjunction with the rotation of the elevator operating lever 24. This movement of the rod 96 pulls or loosens the elevator operating wire 42. This allows the elevator 10c provided at the tip end 10 to move between a raised position and a lowered position.

[0383] The endoscope 1 of this embodiment has a total of four bending operation wires: a pair of up-down bending operation wires 37 and a pair of left-right bending operation wires 38. These four bending operation wires extend from the pulley unit 36 ​​of the bending operation mechanism 35, and then extend in the internal space of the operation section 6 toward the insertion section 5 along the longitudinal axis O2 of the housing 15.

[0384] In this case, a wire guide frame 123 is provided inside the operation section 6 to prevent the four bending operation wires from becoming tangled with one another and to define and guide the extending direction of each bending operation wire. Figures 63 and 64 are views showing the wire guide frame provided inside the operation section of the endoscope in Figure 1. Of these, Figure 63 is a schematic diagram showing how the wire guide frame is arranged inside the operation section. Figure 64 is a schematic diagram showing a structure in which the bending operation wires are held by the wire guide frame.

[0385] As described above, the bending operation wires (37, 38) are composed of a wire core material, an inner sheath (37b), and an outer sheath (37a). In the following description, the reference numerals 37, 38 and 37a, 37b will be omitted and only the component names will be used.

[0386] As shown in the figure, the wire guide frame 123 is formed with a plurality of wire insertion grooves 123a. These plurality of wire insertion grooves 123a are holding portions that hold each of the four bending operation wires. For this reason, the same number of wire insertion grooves 123a as the number of bending operation wires are formed. In this embodiment, four wire insertion grooves 123a are formed to match the four bending operation wires.

[0387] A wire locking member 124 attached to the outer surface of the outer sheath of the bending operation wire is held in the wire insertion groove 123a. This wire locking member 124 is formed by connecting two locking members 124a and a rotation stopper 124b. The configuration of the wire locking member 124 is not limited to this example. For example, the wire locking member 124 may be formed by integrally forming the two locking members 124a and the rotation stopper 124b as a single component.

[0388] The two locking members 124a are generally cylindrical in shape and have through holes through which the bending operation wires with the outer sheaths attached are inserted.

[0389] The rotation stopper 124b has a generally cylindrical shape and is formed with two flat surfaces 124c on a part of the outer circumferential surface that face each other across the central axis O4. The rotation stopper 124b also has a through-hole through which the bending operation wire with the outer sheath attached is inserted.

[0390] The rotation stopper 124b is connected between the two locking members 124a in a sandwiched state. In this case, the through holes of the two locking members 124a and the through hole of the rotation stopper 124b are connected as a single through hole. Therefore, the bending operation wire with the outer sheath attached can be inserted through the through hole.

[0391] The wire locking member 124 configured in this manner is attached by caulking or the like to a predetermined position on the outer surface of the bending operation wire with the outer sheath attached. The wire locking member 124 is then attached to the wire insertion groove 123a of the wire guide frame 123.

[0392] In this case, the wire locking member 124 is disposed so that the two flat surfaces 124c thereof coincide with the opposing wall surfaces 123b of the wire insertion groove 123a. Therefore, the width of the opposing wall surfaces 123b of the wire insertion groove 123a and the width of the two flat surfaces 124c of the wire locking member 124 are set to be approximately equal to or slightly smaller than the width of the two flat surfaces 124c.

[0393] With this configuration, when the wire locking member 124 is placed in the wire insertion groove 123a, its rotation around the central axis O4 is restricted.

[0394] The wire locking member 124 is fixed to the outer surface of the outer sheath of the bending operation wire by caulking or the like.

[0395] The wire locking member 124 attached to the bending operation wire also restricts the rotation of the bending operation wire itself around the central axis O4 when placed in the wire insertion groove 123a.

[0396] Generally, in conventional endoscopes, for example, when the bending operation member is repeatedly operated a predetermined number of times during evaluation testing of the endoscope, or when a test is conducted during environmental testing of the endoscope in which the normal packaging state (a state in which the flexible tube portion is bent or curved) is maintained for a long period of time, such as about one and a half years, angle down or knob play may occur.

[0397] Here, "angle down" refers to a phenomenon in which the bending angle at the maximum bending is smaller than a preset maximum bending angle. Furthermore, "knob play" refers to a phenomenon in which, when the bending operation member is operated, an operating range in which the bending operation mechanism does not respond is created depending on the amount of operation of the bending operation member. Possible causes of such angle down and knob play include, for example, looseness in the bending operation wire.

[0398] For example, in a conventional endoscope, the wire locking member 124 that holds the wire insertion groove 123a of the wire guide frame 123 is configured to be allowed to rotate around the central axis O4 relative to the wire guide frame 123.

[0399] As described above, the outer sheath of the bending operation wire is made of, for example, a coiled tubular member. The outer sheath is fixed to a predetermined fixed portion at its end in a state where its rotation is restricted. Therefore, when the outer sheath rotates around the central axis O4, the outer sheath expands and contracts according to the winding direction of the coil. For example, when the outer sheath contracts and becomes shorter, the bending operation wire inserted into the outer sheath becomes relatively elongated (becomes relatively longer).

[0400] When the bending operation wire is stretched relatively in this way, slack occurs in the bending operation wire, and therefore it becomes impossible to ensure proper operation of the bending operation mechanism in accordance with the amount of operation of the bending operation member.

[0401] Therefore, in this embodiment, the wire locking member 124 is provided with two flat surfaces 124c, and the two flat surfaces 124c are sandwiched and held by the wire insertion grooves 123a of the wire guide frame 123.

[0402] With this configuration, rotation of the wire locking member 124 and the bending operation wire around the central axis O4 of the outer sheath is restricted, preventing the outer sheath from shrinking, thereby preventing phenomena such as angle down and knob play that occur during repeated use or long-term storage.

[0403] Furthermore, during assembly, when placing the wire locking member 124 in the wire insertion groove 123a, the rotational position of the bending operation wire around the central axis O4 of the outer sheath can be set in advance, allowing for relative fine adjustment of the length of the bending wire.

[0404] As described above, according to the first embodiment, by devising the cross-sectional shape of the portion around which the bending operation wires (37, 38) are wound in the pulley bodies (51 a, 52 a) included in the pulley unit 36 ​​in the bending operation mechanism 35 of the endoscope 1, it is possible to suppress an increase in rotational torque during rotational operation of the bending operation members (22, 23) with a simple configuration and at low cost, while arranging the wire fixing portions 51 d, 52 d that fix the wire stators 37 x, 38 x in the pulley bodies (51 a, 52 a). Therefore, it is possible to maintain good operability of the bending operation members (22, 23) and prevent the pulley bodies (51 a, 52 a) from becoming larger.

[0405] Next, a second embodiment of the present invention will be described with reference to Figs. 65 to 71. Fig. 65 is an exploded perspective view showing a pulley unit in an endoscope according to the second embodiment of the present invention from one end. Fig. 66 is an exploded perspective view showing the pulley unit of Fig. 65 from the other end. Fig. 67 is a plan view schematically showing a state when the vertical bending pulley in the bending operation mechanism of Fig. 65 has rotated to a first rotation terminal position of the auxiliary plate. Fig. 68 is a plan view schematically showing a state when the vertical bending pulley in the bending operation mechanism of Fig. 65 has rotated to a second rotation terminal position of the auxiliary plate. Fig. 69 is a plan view schematically showing a state when the vertical bending pulley and auxiliary plate in the bending operation mechanism of Fig. 65 have rotated to the first rotation terminal position. Fig. 70 is a plan view schematically showing a state when the vertical bending pulley and auxiliary plate in the bending operation mechanism of Fig. 65 have rotated to the second rotation terminal position. 71 is a perspective view showing an auxiliary plate selectively used for the up and down bending pulley in the bending operation mechanism of FIG. 65. FIG.

[0406] This embodiment differs from the first embodiment described above mainly in the configuration of the pulley unit 36. The remaining configuration is the same as that of the first embodiment described above. Therefore, in the following description, the same components as those of the first embodiment described above will be denoted by the same reference numerals and will not be described again.

[0407] The vertical bending pulley 51 in the pulley unit 36 ​​of this embodiment has an auxiliary protrusion 51g instead of the above-mentioned protrusion 51f (see FIG. 66). This auxiliary protrusion 51g protrudes in the thickness direction of the vertical bending pulley body 51a. More specifically, the auxiliary protrusion 51g has a partial arc shape with an outer diameter substantially the same as the outer diameter of the vertical bending pulley body 51a. This auxiliary protrusion 51g protrudes, for example, from the other end side of the vertical bending pulley body 51a in the direction of the central axis O3.

[0408] An auxiliary plate 100 is interposed between the vertical bending pulley 51 and the first case member 61. The auxiliary plate 100 has a generally disk shape. The outer diameter of the auxiliary plate 100 is set to be larger than the outer diameter of the vertical bending pulley 51. A through-hole 100a is provided in the center of the auxiliary plate 100, penetrating in the direction of the central axis O3 of the pulley unit 36.

[0409] An annular flange 100b is formed on the outer edge of the auxiliary plate 100, protruding toward the other end of the central axis O3. The inner diameter of this flange 100b is set to be approximately the same as the outer diameter of the auxiliary protrusion 51g. The auxiliary protrusion 51g of the vertical bending pulley 51 is inserted into this flange 100b. As a result, the vertical bending pulley 51 is connected to the auxiliary plate 100 in a rotatable state.

[0410] A partially arcuate auxiliary stopper 100c is formed on the inside of the flange 100b. This auxiliary stopper 100c is able to freely abut against the auxiliary protrusion 51g. As a result, the relative rotation angle range between the auxiliary plate 100 and the vertical bending pulley 51 is determined by the auxiliary stopper 100c and the auxiliary protrusion 51g (see Figures 67 and 68).

[0411] Furthermore, a protrusion 100d serving as a contact portion is provided on the auxiliary plate 100. The protrusion 100d has, for example, a partial arc shape and protrudes in the outer diameter direction of the auxiliary plate 100.

[0412] When the auxiliary plate 100 is sandwiched together with the vertical bending pulley 51 between the case main body 60 and the first case member 61, the convex portion 100d is positioned opposite the other end face of the case main body 60. In other words, the convex portion 100d is positioned so as to be able to come into contact with each stopper member 67. This allows the auxiliary plate 100 to rotate freely within the pulley case 53 (60, 61, 62) within the angular range defined by each stopper member 67.

[0413] As a result, the vertical bending pulley 51 can freely rotate within an angle range that is the sum of the angle range allowed by the auxiliary plate 100 relative to the vertical bending pulley 51 and the angle range allowed by the pulley case 53 relative to the auxiliary plate 100 (see Figures 69 and 70).

[0414] Furthermore, the left-right bending pulley 52 in the pulley unit 36 ​​of this embodiment has an auxiliary protrusion 52g instead of the above-mentioned protrusion 52f (see FIG. 65). This auxiliary protrusion 52g protrudes in the thickness direction of the left-right bending pulley main body 52a. More specifically, the auxiliary protrusion 52g has a partial arc shape with an outer diameter substantially the same as the outer diameter of the left-right bending pulley main body 52a. This auxiliary protrusion 52g protrudes, for example, from one end side of the pulley unit 36 ​​in the direction of the central axis O3.

[0415] An auxiliary plate 101 is interposed between the left-right bending pulley 52 and the second case member 62. The auxiliary plate 101 has a generally disk shape. The outer diameter of the auxiliary plate 101 is set to be larger than the outer diameter of the left-right bending pulley 52. ​​A through-hole 101a is provided in the center of the auxiliary plate 101, penetrating in the direction of the central axis O3 of the pulley unit 36.

[0416] An annular flange 101b is formed on the outer edge of the auxiliary plate 101, protruding toward one end of the central axis O3. The inner diameter of this flange 101b is set to be approximately the same as the outer diameter of the auxiliary protrusion 52g. The auxiliary protrusion 52g of the left-right bending pulley 52 is inserted into this flange 101b. As a result, the left-right bending pulley 52 is connected to the auxiliary plate 101 in a rotatable state.

[0417] Furthermore, a partial arc-shaped auxiliary stopper 101c is formed on the inside of the flange 101b. This auxiliary stopper 101c is able to freely come into contact with the auxiliary protrusion 52g. As a result, the relative rotation angle range between the auxiliary plate 101 and the left-right bending pulley 52 is determined by the auxiliary stopper 101c and the auxiliary protrusion 52g.

[0418] Furthermore, a protrusion 101d serving as a contact portion is provided on the auxiliary plate 101. This protrusion 101d has, for example, a partial arc shape and protrudes in the outer diameter direction of the auxiliary plate 101.

[0419] When the auxiliary plate 101 is sandwiched between the case main body 60 and the second case member 62 together with the left-right bending pulley 52, the convex portion 101d is positioned opposite the other end face of the case main body 60. In other words, the convex portion 101d is positioned so as to be able to come into contact with each stopper member 68. This allows the auxiliary plate 101 to rotate freely within the pulley case 53 (60, 61, 62) within the angular range defined by each stopper member 68.

[0420] As a result, the left / right bending pulley 52 is able to rotate freely within an angle range that is the sum of the angle range that the auxiliary plate 101 allows for the left / right bending pulley 52 and the angle range that the pulley case 53 allows for for the auxiliary plate 101.

[0421] According to the second embodiment having such a configuration, in addition to the effects obtained in the first embodiment described above, the effect of being able to appropriately expand the rotation angle range allowable for the up-down bending pulley 51 and the left-right bending pulley 52 is achieved.

[0422] Here, for example, as shown in FIG. 71, the auxiliary plates (100, 101) can be replaced as appropriate depending on the specifications of the endoscope 1 (for example, the limit angles for up and down bending and the limit angles for left and right bending).

[0423] The present invention is not limited to the above-described embodiments, and various modifications and variations are possible, and these are also within the technical scope of the present invention.

[0424] That is, the endoscope bending operation mechanism shown in each of the above-mentioned embodiments is configured such that the convex portions are provided on the pulleys (pulleys for vertical bending and pulleys for horizontal bending) and the attachment portions are provided on the pulley case, but it goes without saying that the endoscope bending operation mechanism is not limited to this configuration. For example, the endoscope bending operation mechanism can also be configured such that the attachment portions are provided on the pulleys (pulleys for vertical bending and pulleys for horizontal bending) and the convex portions are provided on the pulley case.

[0425] Furthermore, although the endoscope bending mechanism shown in each of the above-described embodiments is configured to bend the bending portion in the up-down direction and the left-right direction, it is needless to say that it is not limited to this configuration. For example, the endoscope bending mechanism may be configured to bend the bending portion only in either the up-down direction or the left-right direction.

[0426] Furthermore, the number of attachment parts and stopper members provided on an endoscope bending mechanism need only be one. Furthermore, the stopper member may be shared by endoscope bending mechanisms of different types of endoscopes. For example, the shape of the stopper member attached to the bending mechanism of a duodenal endoscope and the shape of the stopper member attached to the bending mechanism of a colonoscope may be the same. That is, an endoscope system may be provided in which the stopper member attached to the endoscope bending mechanism of a first endoscope (e.g., a duodenal endoscope) and the stopper member attached to the bending mechanism of a second endoscope (e.g., a colonoscope or a gastric endoscope) have the same shape.

[0427] The present invention is not limited to the above-described embodiments, and various modifications and applications can be made without departing from the spirit and scope of the invention. Furthermore, the above-described embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining the disclosed multiple constituent elements. For example, if the problem to be solved by the invention can be solved and the effects of the invention can be obtained even if some constituent elements are deleted from all the constituent elements shown in one embodiment, the configuration from which these constituent elements are deleted can be extracted as the invention. Furthermore, constituent elements from different embodiments may be appropriately combined. The present invention is not limited by specific embodiments other than as limited by the appended claims.

Claims

1. An operating mechanism for an insertion device comprising: a wire that acts on a subject by reciprocating between the tip of an insertion section that is inserted longitudinally of the insertion device and an operating section that is arranged on the base end side of the insertion section; a drum that winds the wire around it at least once; a pulley that includes a flange that prevents the wire from falling off the drum and rotates around a central axis in response to external operation; and a wire fixing section that fixes the wire to the pulley, wherein the cross section of the drum perpendicular to the central axis is formed so that the radius of the part where the wire fixing section is not provided is smaller than the radius of the part where the wire fixing section is provided, and the drum has a non-circular oval shape.

2. The operating mechanism for an insertion instrument according to claim 1, characterized in that, in a cross section perpendicular to the central axis, the drum includes a circumferential region where the wire fixing portion is not provided and the radius is constant over an angle of 180 degrees (°) or more out of an angle of 360 degrees (°).

3. The operating mechanism for an insertion instrument according to claim 2, wherein the radius of the drum in the area with a constant radius is 6 mm to 7 mm.

4. The operating mechanism of the insertion instrument according to claim 1, wherein the drum includes a parabolic shape in a cross section perpendicular to the central axis.

5. The operating mechanism for an insertion instrument according to claim 4, characterized in that the drum is composed of a combination of a semicircular portion and a parabolic portion in a cross section perpendicular to the central axis.

6. The operating mechanism for an insertion instrument according to claim 5, wherein the wire fixing portion is provided in the portion that describes the parabola.

7. The operating mechanism for an insertion instrument according to claim 1, characterized in that the wire fixing portion is provided at a position passing through the central axis and along the longitudinal direction when the pulley is in a neutral state in which no rotation is being applied to the pulley.

8. The operating mechanism for an insertion instrument according to claim 7, characterized in that the wire fixing portion is provided on a line that passes through the central axis and intersects the longitudinal direction at an angle of 90 degrees (°) when the pulley is in a neutral state with no rotation applied to it.

9. The operating mechanism for an insertion instrument according to claim 1, characterized in that the wire fixing portion is provided at a position that passes through the central axis and is not aligned along the longitudinal direction when the pulley is in a neutral state in which no rotation is being applied to the pulley.

10. The operating mechanism for an insertion instrument according to claim 1, characterized in that the wire is wound around the drum by five-quarters (5 / 4) of the circumference of the drum when the pulley is in a neutral state with no rotation being applied to the pulley.

11. The operating mechanism of an insertion instrument according to claim 1, characterized in that one end of the wire is provided with an engaging part having a diameter larger than that of the remaining part of the wire, and the wire fixing part includes a structure for engaging the engaging part with an engaging part provided on the flange or the drum.

12. The operating mechanism for an insertion instrument as described in claim 11, characterized in that the engaging part is a fixed piece attached by crimping to one end of the wire, and the flange or the drum is provided with a recess for engaging the fixed piece.

13. The operating mechanism for an insertion instrument according to claim 1, characterized in that the pulley is provided with a protrusion that protrudes radially perpendicular to the central axis and engages with an external part to restrict the rotation range.

14. The operating mechanism for an insertion instrument according to claim 13, characterized in that the protrusion is provided at a position in the circumferential direction of the drum where the wire fixing part is provided.

15. An operating mechanism for an insertion instrument as described in claim 13, further comprising a holding member for holding the pulley, the holding member having a plurality of grooves formed radially around the central axis and a plate member attached to the grooves and protruding in the direction in which the pulley is provided, the protrusion of the pulley being configured to be freely rotatable within an angle range up to the point where it comes into contact with the plate member.

16. The operating mechanism of claim 1, further comprising a rotating shaft member that transmits rotational force generated by user operation to the pulley about the central axis, one end of the rotating shaft member having an elliptical shape including straight lines in a cross section perpendicular to the central axis, and the pulley having a connecting portion that connects to the rotating shaft member and has a shape corresponding to the one end of the rotating shaft member about the central axis.

17. An insertion device comprising: an insertion section that is inserted into a subject in the longitudinal direction of the insertion device; a wire that acts by reciprocating between the tip of the insertion section and an operation section provided on the base end side of the insertion section; a drum that winds the wire around it at least once; a pulley that includes a flange configured to prevent the wire from falling off the drum and rotates around a central axis in response to external operation; and a wire fixing section that fixes the wire to the drum, wherein the cross-sectional shape of the drum perpendicular to the central axis is formed so that the radius of the part where the wire fixing section is provided is smaller than the radius of the part where the wire fixing section is not provided, and the drum has a non-circular oval shape.

18. The insertion device of claim 17, which is a single-use endoscope that is disposed of after a single use.

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