CN117045177A - Endoscope with a lens - Google Patents

Abstract

The present invention provides an endoscope, which is composed of: a distal end structure portion provided at a distal end portion of an insertion portion to be inserted into a subject; a forceps lifting seat rotatably provided with respect to the distal end structure portion for lifting a treatment tool protruding from a first opening portion provided in the distal end structure portion; an operation wire protruding from a second opening provided in the front end structure portion and reciprocating in a longitudinal direction of the insertion portion; a wire pulling part formed protruding from the forceps raising seat in a direction intersecting the longitudinal direction, holding a front end of the operation wire, and transmitting a pulling force generated by the reciprocation of the operation wire to the forceps raising seat; and a tip protruding portion provided on the tip structure portion, the tip protruding portion having a guide surface for guiding the reciprocating movement of the operation wire and a restriction portion provided on an end portion of the guide surface to restrict a rotation angle at which the wire pulling portion can rotate together with the forceps raising seat.

Description

endoscope

Technical field

The present invention relates to an endoscope provided with a forceps lifting base that changes the protruding direction of a treatment instrument or the like protruding outward from a front end structural portion of an insertion portion.

Background technique

Conventionally, endoscopes have been widely used in the medical field, industrial field, and the like.

A general endoscope is usually configured to have an insertion part formed in an elongated tube shape and inserted into a subject, and to have a tip structure part at the tip of the insertion part.

Furthermore, for example, a camera unit, a lighting unit, etc. are provided in the front-end structural part.

Furthermore, some endoscopes are configured such that the insertion portion of the conventional endoscope has an elongated tube-shaped conduit (so-called treatment instrument insertion conduit).

Treatment equipment and the like can be inserted into this pipeline.

Here, the treatment instrument or the like is an instrument equipped with forceps or the like at the front end and used for performing various treatments such as biopsy of a part of the biological tissue in the body cavity and excision of the lesion in the body cavity.

In addition, conventional endoscopes can insert treatment instruments and the like into the duct with the insertion portion inserted into the body cavity of the subject, and the distal end portions of the treatment instruments and the like can protrude outside the distal end structure portion.

By setting it in such a state, various treatments using treatment instruments and the like can be performed.

In addition, conventionally, for example, an endoscope has been disclosed that includes a forceps lifting base in a front end structure portion for changing the protruding direction of a treatment instrument or the like that protrudes outward from the front end structure portion, mainly the duodenum or the like. Disposal object.

Regarding such an endoscope, various proposals have been proposed in Japanese Patent Publication No. 2015-165839, Japanese Patent Publication No. H08-56900, Japanese Patent Publication No. H04-218134, Japanese Patent Publication No. 3159464, and the like.

The above-mentioned Japanese Patent Publication No. 2015-165839, the above-mentioned Japanese Patent Publication No. H08-56900, etc. disclose an endoscope having a forceps lifting base and a mechanism for operating the forceps lifting base. Located in each space separated by wall members, etc.

In addition, the above-mentioned Japanese Patent Publication No. H04-218134, the above-mentioned Japanese Patent No. 3159464, etc. disclose an endoscope that does not provide a partition wall between the forceps lifting base and the forceps lifting base operating mechanism. The pliers lifting base is connected to the operating wire to directly pull the pliers.

Among these endoscopes, there is disclosed a structure in which a part of the rotation limiting portion for limiting the rotation range of the forceps lifting base is disposed in the movable area of the treatment instrument.

Contents of the invention

An endoscope according to one aspect of the present invention includes: a front end structure portion provided at the front end portion of an insertion portion inserted into a subject; and a forceps lifting base provided so as to be rotatable relative to the front end structure portion. To lift the treatment instrument protruding from the first opening provided in the front end structural part; an operation wire protrudes from the second opening provided in the front end structural part in the length direction of the insertion part Perform reciprocating motion; a wire pulling portion is formed protrudingly from the pliers lifting seat in a direction intersecting the length direction, holding the front end of the operating wire, and transferring the reciprocating motion of the operating wire to the The traction force is transmitted to the pliers lifting base; and a front-end protruding portion is provided on the front-end structural portion and has a guide surface and a limiting portion. The guide surface guides the reciprocating motion of the operating wire, so The limiting portion is provided at an end of the guide surface and is used to limit the rotation angle at which the wire pulling portion can rotate together with the pliers lifting base.

Description of the drawings

FIG. 1 is a diagram schematically showing an entire endoscope system including an endoscope according to an embodiment of the present invention;

FIG. 2 is an enlarged perspective view of the main part of the front end structural part of the endoscope according to one embodiment of the present invention;

3 is an enlarged perspective view of the main part of the front end structural part of the endoscope according to one embodiment of the present invention;

Fig. 4 is an exploded perspective view showing a state in which the front end cover of the front end structural part of Fig. 2 is removed;

Figure 5 is an enlarged perspective view of only the pliers lifting base in the front-end structural part of Figure 2;

Fig. 6 is an enlarged perspective view showing the structure of the forceps lifting base and the forceps lifting base operating mechanism in the front end structure part of Fig. 2;

Figure 7 is an enlarged top view when viewed from the direction of arrow mark [7] in Figure 6;

Fig. 8 is a perspective view showing the internal structure of the front end structural part of Fig. 2;

FIG. 9 is an enlarged perspective view of the main part showing the installation structure of the operating wire in the front end structure part of FIG. 2 relative to the wire pulling part of the pliers;

FIG. 10 is a diagram showing a modified example of the installation structure of the operation wire with respect to the wire pulling part in FIG. 9 ;

Figure 11 is a diagram showing a state in which the forceps lifting base is in the middle of being lifted in the front end structure part;

Figure 12 is a diagram showing the state in which the pliers lifting base is in the middle of being lifted in the front end structural part after the front end cover is removed;

Figure 13 is a diagram showing the maximum lifted state of the pliers lifting base in the front end structure part;

Figure 14 is a diagram showing the maximum raised state of the pliers lifting base in the front end structural part after the front end cover is removed;

Figure 15 is a view showing the state in which the forceps lifting base and the treatment instrument are inverted together with the front end structure part after the front end cover is removed;

Fig. 16 is a diagram showing the state in which the treatment instrument has reached the maximum lifted position with the front end structural part with the front end cover removed;

FIG. 17 is a diagram showing a modified example of the distal end structural portion of the endoscope according to the embodiment of the present invention;

FIG. 18 is a diagram schematically showing the appearance of the front end structural portion of the endoscope according to one embodiment of the present invention;

Fig. 19 is a diagram showing a cross-section along line [18]-[18] in Fig. 18;

Fig. 20 is a diagram showing a cross section along the plane shown by [20] to [20] in Fig. 19;

FIG. 21 is a diagram showing a cross section along line [21] to [21] in FIG. 18 .

Detailed ways

Generally, examples of structures of conventional endoscopes include structures disclosed in the above-mentioned Japanese Patent Publication No. 2015-165839, Japanese Patent Publication No. H08-56900, and the like.

In the case of an endoscope having such a structure in which a forceps lifting base and a mechanism for operating the forceps lifting base are arranged in each space separated by a wall member or the like, the forceps lifting base is included in the structure. The structure of the front end structural part of the mechanism part for raising the seat may become complicated.

Therefore, in order to further simplify the structure, for example, the structure of the endoscope disclosed in the above-mentioned Japanese Patent Publication No. H04-218134, the above-mentioned Japanese Patent No. 3159464, etc. can be cited.

The front end structural part of such an endoscope has a structure in which a partition wall is not provided between the forceps lift base and the forceps lift base operating mechanism, and the forceps lift base is connected to the operation wire for direct pulling.

However, when a structure is applied that does not provide a partition wall between the forceps lift base and the forceps lift base operating mechanism, there is a possibility that structures or operating wires near the front end opening of the front end structural part may hinder the insertion of treatment instruments, etc. pull.

As an example of the cause of this phenomenon, it is considered that, for example, a rotation restricting portion or the like near the front end opening of the front end structural portion, an operating wire, etc. are present in the movable area of the treatment instrument or the like.

According to the embodiments of the present invention described below, it is possible to provide an endoscope that can simplify the structure of the front end structure, does not hinder the insertion and removal of treatment instruments, etc., and can ensure the good performance of treatment instruments and the like. operability.

Hereinafter, the present invention will be described based on the embodiments shown in the drawings.

Each of the drawings used in the following description is schematically shown. In order to show each component in a size that can be recognized in the drawing, the dimensional relationship, scale, etc. of each component may be set for each individual component. The components are represented differently.

Therefore, the present invention is not limited to the number of each component, the shape of each component, the size ratio of each component, the relative positional relationship of each component, etc. shown in the drawings.

First, the schematic structure of an endoscope system including an endoscope according to one embodiment of the present invention will be described below using FIG. 1 .

FIG. 1 is a diagram schematically showing an entire endoscope system including an endoscope according to one embodiment of the present invention.

In addition, the basic structure of the endoscope system 1 shown in FIG. 1 is substantially the same as that of the conventional endoscope system.

Therefore, the following description is limited to a schematic description of each structural component in the endoscope system 1 .

As shown in FIG. 1 , the endoscope system 1 of this embodiment is configured to include an endoscope 2, a light source device 3, a video processor 4, a display device 5, an endoscope treatment instrument 40, and the like.

The endoscope 2 is configured to have an insertion portion 9 having a substantially elongated tube shape, an operating portion 10, a universal cable 12, and the like.

The insertion part 9 is a component inserted into the subject.

The insertion part 9 is formed by arranging the front-end structural part 6, the bending part 7, and the flexible tube part 8 in order from the front-end side.

As a result, the entire insertion portion 9 is formed into a substantially elongated tube shape.

Furthermore, the operation part 10 is connected to the proximal end side of the insertion part 9 .

Furthermore, an endoscopic treatment instrument (hereinafter simply referred to as a treatment instrument) 40 can be inserted into the endoscope 2 , the details of which will be described later.

Therefore, the treatment instrument insertion channel 17 , which is a conduit for inserting the treatment instrument 40 , is provided in the insertion portion 9 from the front end to the base end.

Various structural components such as a camera unit, a lighting unit, and a forceps lifting base are provided inside the front end structural portion 6 (not shown in FIG. 1 ; details will be described later).

The operating unit 10 is configured to include an operating unit main body, a plurality of operating members, a forceps insertion port 11 and the like.

The entire main body of the operating part is formed into a substantially box-shaped shape, and constitutes a gripping part.

As mentioned above, the insertion part 9 is extended from the operation part main body.

The plurality of operating members are operating members for performing various operations of the endoscope 2 .

The plurality of operating members are provided at predetermined positions on the outer surface of the operating unit body.

The forceps insertion port 11 is provided at a predetermined position close to the front end of the operating portion body of the operating portion 10 .

The forceps insertion port 11 is the proximal end opening of the treatment instrument insertion channel 17 of the insertion portion 9 .

Furthermore, the treatment instrument insertion channel 17 is connected on the front end side to the first front end side opening 20a (not shown in FIG. 1 ; see FIGS. 7 and 8 described below) of the front end structural part 6 .

With this structure, the distal end of the treatment instrument 40 inserted through the forceps insertion port 11 protrudes outward from the first distal end side opening 20 a of the distal end structure part 6 .

The universal cable 12 is a tubular member extending from the side of the operation part 10 .

An endoscope connector 13 is provided at the front end of the universal cable 12 .

This endoscope connector 13 is connected to the light source device 3 .

The light source device 3 is a device that supplies illumination light to a lighting unit provided inside the distal end structure portion 6 of the insertion portion 9 of the endoscope 2 .

The illumination light emitted from the light source device 3 is transmitted from the endoscope connector 13 to the light source device 3 through an optical fiber cable or the like (not shown) that is inserted into the universal cable 12 , the operating unit 10 , and the insertion unit 9 . The lighting unit of the front end structural part 6 of the insertion part 9 of the endoscope 2 .

Then, the illumination light passes through the illumination optical component provided in the front end structure part 6 and is irradiated toward the observation object in the vicinity of the front end structure part 6 .

In addition, as an example of the lighting unit, a structure in which the illumination light from the light source device 3 is transmitted to the front end structural part 6 through an optical fiber cable or the like is exemplified, but the structure is not limited to this structure.

For example, a structure may be adopted in which an LED (Light Emitting Diode) or the like as an illumination light source is provided inside the front end structure part 6 and the light emission of the illumination light source (LED) is controlled by the light source device 3 .

The endoscope cable 14 extends laterally from the endoscope connector 13 .

An electrical connector portion 15 is provided at the front end of the endoscope cable 14 .

This electrical connector part 15 is connected to the video processor 4 .

The video processor 4 is a control device including a control circuit that controls the entire endoscope system 1 and the like.

In this case, the video processor 4 includes a signal processing circuit, a control processing circuit, and the like.

The signal processing circuit has, for example, a structure that receives an imaging signal from an imaging unit (not shown) provided inside the front end structure portion 6 of the insertion portion 9 of the endoscope 2 and performs predetermined signal processing. .

The control processing circuit has a structure that outputs a control signal for driving the imaging unit, for example.

The video processor 4 and the camera unit are electrically connected through a signal transmission cable (not shown).

Therefore, the signal transmission cable is configured to be inserted from the electrical connector part 15 into the endoscope cable 14 , the endoscope connector 13 , the universal cable 12 , the operation part 10 , and the front end structure part 6 of the insertion part 9 between camera units.

With this structure, the imaging signal output from the imaging unit, the control signal output from the video processor 4, and the like are transmitted between the imaging unit and the video processor 4 through the signal transmission cable.

In addition, as one form of the signal transmission cable, for example, a composite cable in which a plurality of cables are bundled and covered with an outer shield, an outer tube, or the like is used.

The video processor 4 and the display device 5 are connected using a video cable 16 .

The video cable 16 transmits image signals, control signals, and the like output from the video processor 4 to the display device 5 .

The display device 5 receives an image signal and a control signal output from the video processor 4 and displays an endoscopic image, various information, and the like in a predetermined format based on the display format corresponding to the received control signal.

Furthermore, in the endoscope system 1 of this embodiment, the treatment instrument 40 is inserted into the endoscope 2 in a detachable manner.

In FIG. 1 , a state in which the treatment instrument 40 is inserted into a predetermined position of the endoscope 2 is shown.

The treatment instrument 40 is prepared in various forms. The treatment instrument 40 is appropriately selected and used depending on the site to be treated, the type of treatment, and the like.

Next, the detailed structure of the distal end structure portion 6 in the endoscope 2 of the present embodiment included in the endoscope system 1 configured in this way will be described below using FIGS. 2 to 10 .

2 and 3 are enlarged perspective views of main parts of the endoscope according to the embodiment of the present invention.

2 is a perspective view of the front end surface of the front end structure portion, viewed from a position close to the oblique left side.

FIG. 3 is a perspective view of the front end surface of the front end structure portion viewed from a position close to the diagonally right side surface.

FIG. 4 is an exploded perspective view showing a state in which the front end cover of the front end structural part is removed.

FIG. 5 is an enlarged perspective view of only the pliers lifting base among the internal structural components of the front end structural part;

FIG. 6 is an enlarged perspective view showing the structure of the forceps lift base and the forceps lift base operating mechanism.

FIG. 7 is an enlarged plan view of the front end structural part when viewed from the direction of arrow [7] in FIG. 6 .

FIG. 8 is a perspective view of the internal structure of the front-end structural part with the front-end cover removed when viewed from a different direction than FIG. 4 .

FIG. 9 is an enlarged perspective view of the main part showing the installation structure of the operating wire with respect to the wire pulling part.

FIG. 10 shows a mounting structure of the operation wire with respect to the wire pulling part, similarly to FIG. 9 , and is a diagram showing a modification of the large-diameter portion of the operation wire.

First, the schematic structure of the distal end structure part 6 in the endoscope 2 of this embodiment will be described using FIGS. 2 to 4 .

As shown in the figure, the front end structural part 6 is composed of a front end structural part main body 20 and a front end cover 30 .

In addition, in the following description, the axis indicated by the symbol Ax in FIGS. 2 and 3 will be called the insertion axis of the insertion part 9 (the front-end structural part 6).

In addition, the direction along the insertion axis Ax is called the longitudinal direction of the insertion portion 9 .

The front end structural part main body 20 is a structural member provided at the front end part of the insertion part 9 .

The front-end structural part main body 20 is formed using a metal material such as stainless steel, for example.

The front end structure body 20 is provided with a lighting unit 21, a camera unit 22, an air and water supply nozzle 23, an insulating block 24, a forceps lifting base 25, and a lifting base operating mechanism part 27 including a part of the operating wire 26 (see FIG. 3 etc. (described in detail later), etc.

Here, in the front-end structural part main body 20, the area where the lighting unit 21, the imaging unit 22, the air and water supply nozzle 23, etc. are arrange|positioned is called a 1st area.

The first area is an area close to the right when viewed toward the front surface of the front end structural portion 6 .

In FIG. 6, reference numeral B1 denotes the first area.

In addition, in the front-end structural part main body 20, the area where the insulating block 24, the forceps lifting base 25, etc. are arrange|positioned is called a 2nd area.

The second region is a region located substantially in the center when viewed toward the front surface of the front end structural portion 6 .

In Fig. 6, reference numeral B2 indicates the second area.

Moreover, in the front-end structural part main body 20, the area|region in which the lift base operation mechanism part 27 including a part of the operation wire 26 is provided is called a 3rd area|region.

The third area is an area close to the left side when viewed toward the front surface of the front end structural portion 6 .

In Fig. 6, reference numeral B3 indicates the third area.

In addition, a wire pulling portion 25c (described in detail later) that holds the tip of the operation wire 26 is also arranged in the third area.

As described above, the lighting unit 21 , the imaging unit 22 , the air and water supply nozzles 23 and the like are arranged in the first area B1 of the front end structural part body 20 .

Among them, the lighting unit 21 is configured to include an illumination optical component that receives illumination light transmitted from the light source device 3 through an optical fiber cable or the like, and illuminates a predetermined range in a predetermined direction outside the front end structure part 6 . irradiation.

In addition, the structure of the lighting unit 21 itself is the same as that of the lighting unit mounted on a conventional endoscope.

Therefore, detailed description of the lighting unit 21 is omitted.

The imaging unit 22 is a structural component composed of an imaging optical system, an imaging element, an imaging element drive circuit, and the like.

The imaging optical system is composed of optical lenses and the like that form an optical image of an object to be observed.

An imaging element is an electronic component that receives an optical image formed by an imaging optical system and performs photoelectric conversion.

This imaging element is driven by an imaging element driving circuit.

The imaging element driving circuit receives the instruction signal from the video processor 4 to drive the imaging element.

The image data photoelectrically converted by the imaging element is sent to the video processor 4 through the imaging element driving circuit.

The video processor 4 receives the received image data and performs predetermined image data processing.

In addition, the structure of the imaging unit 22 itself is the same as that of the imaging unit mounted on a conventional endoscope.

Therefore, detailed description of the imaging unit 22 is omitted.

The air and water supply nozzle 23 is a structural member that outputs liquid or gas when water or air is supplied outward from the front end structural portion 6 .

For example, when a predetermined water supply operation is performed by operating a predetermined operation member among a plurality of operation members provided in the operation unit 10 , the air supply and water supply nozzle 23 outputs an output signal to the imaging optical system of the imaging unit 22 that is exposed to the outside. The surface of the observation window is cleaned with water.

As mentioned above, the insulating block 24, the forceps lifting base 25, etc. are arrange|positioned in the 2nd area B2 of the front-end structural part main body 20.

In addition, a first front end side opening 20 a that is a first opening connected to the treatment instrument insertion channel 17 is formed in the second region B2 (see FIGS. 7 and 8 ).

As described above, the treatment instrument 40 is inserted from the forceps insertion opening 11 and inserted into the treatment instrument insertion channel 17 .

Furthermore, the front end region (front end portion) of the treatment instrument 40 protrudes toward the outside from the first front end side opening 20 a (see FIGS. 7 and 8 ) of the front end structural part 6 .

At this time, the forceps lifting base 25 performs a predetermined lifting action to change the protruding direction of the front end region of the treatment instrument 40 (details will be described later).

The insulating block 24 is a structural member that is interposed between the treatment instrument 40 and the front end structural part main body 20 when the treatment instrument 40 is lifted by the forceps lifting base 25 as described above.

The insulating block 24 is formed of ceramic material such as alumina.

With this structure, the insulating block 24 cuts off the electrical conduction between the treatment instrument 40 and the front end structure body 20 when the treatment instrument 40 is lifted by the forceps lifting base 25 .

At the same time, the insulating block 24 limits movement of the treatment instrument 40 beyond the specified maximum raised position.

That is, when the treatment instrument 40 is lifted by the forceps lifting base 25, the treatment instrument 40 comes into contact with the insulating block 24, so that the treatment instrument 40 is sandwiched between the forceps lifting base 25 and the insulating block 24. In this state, the pliers lifting base 25 no longer rotates.

This restricts the treatment instrument 40 from further moving in the lifting direction.

The forceps lifting base 25 is a structural member that changes the protruding direction of the treatment instrument 40 protruding outward from the distal end structural portion 6 (the first distal end side opening 20a (see FIGS. 7 and 8 )).

As described above, when the treatment instrument 40 is inserted from the forceps insertion port 11 and inserted into the treatment instrument insertion channel 17 , a part of its front end protrudes outward from the first front end side opening 20 a of the front end structure body 20 .

When the treatment instrument 40 is in this state, when the forceps lifting base 25 is rotated in the lifting direction, the treatment instrument 40 is lifted together with the forceps lifting base 25 .

Here, the structure of the forceps lifting base 25 is demonstrated in further detail using FIG. 5 etc. FIG.

The forceps lifting base 25 is provided rotatably relative to the tip structure part 6 .

Specifically, the forceps lifting base 25 is provided rotatably about the rotation axis Ax2 (refer to FIGS. 4 and 5 ) substantially perpendicular to the insertion axis Ax (refer to FIGS. 2 to 4 ) of the distal end structure part 6 .

Here, arrow R1 in FIG. 4 indicates the lifting direction of the forceps lifting base 25 .

Similarly, arrow R2 in FIG. 4 indicates the inversion direction of the pliers lifting base 25 .

Furthermore, in this case, the rotation of the forceps lifting base 25 is restricted within a predetermined range (details will be described later).

The pliers lifting base 25 is formed of, for example, a metal material such as stainless steel.

As shown in FIG. 5 , the forceps lifting base 25 is formed with a rotation center hole 25a, a treatment instrument guide portion 25b, a wire pulling portion 25c, a wire engaging portion 25d, a stopper contact surface 25s, and the like.

The rotation center hole 25a is a through hole to which a spindle member 28 that pivotally supports the forceps lifting base 25 in a rotatable manner in a predetermined direction is fixed.

Here, the support shaft member 28 is arranged at a predetermined position of the front end structural part main body 20 in parallel with the rotation axis Ax2.

In the present embodiment, the support shaft member 28 is, for example, disposed between the first region B1 and the third region B3 (the distal protruding portion 20x; described later) in the distal end structure body 20 .

The treatment instrument guide part 25b is a contact surface formed in order to contact the treatment instrument 40 protruding from the first distal side opening 20a and guide the traveling direction of the treatment instrument 40 to a predetermined direction.

The treatment instrument guide portion 25b is formed in a substantially concave shape in cross section in a direction perpendicular to the insertion axis Ax, for example.

In this case, it is preferable that the substantially concave shape of the treatment instrument guide portion 25 b is formed so that the diameter is substantially larger than the diameter near the front end portion of the treatment instrument 40 .

In this way, in the endoscope 2 , the protruding direction of the front end portion of the treatment instrument 40 inserted into the treatment instrument insertion channel 17 is guided by the forceps lifting base 25 within a predetermined range.

The wire pulling part 25c is a structural part that holds the tip of the operation wire 26.

The wire pulling part 25c has a function of transmitting the traction force generated by the reciprocating movement of the operation wire 26 along the insertion axis Ax (described in detail later) to the forceps lifting base 25.

At this time, the operation wire 26 and the wire pulling part 25c function as a part of the lift base operating mechanism part 27.

The wire pulling part 25c is integrally formed with the pliers lifting base 25.

In this case, the wire pulling part 25c and the treatment instrument guide part 25b in the forceps lifting base 25 are formed so that at least a part thereof has a surface that is integrally connected to each other (see reference numeral 25bb in FIG. 5 ).

The wire pulling portion 25c is formed at a position protruding toward the third region B3 side in a direction substantially perpendicular to the insertion axis Ax (a direction substantially parallel to the rotation axis Ax2).

In other words, the wire pulling portion 25c is formed at a position offset from the treatment instrument guide portion 25b toward the third region B3 in a direction substantially perpendicular to the insertion axis Ax (a direction substantially parallel to the rotation axis Ax2).

In addition, although the structural example in which the wire pulling part 25c and the forceps lifting base 25 are integrally formed is shown, it is not limited to this structural example.

For example, the wire pulling part 25 c formed separately from the forceps lifting base 25 may be attached to a predetermined position of the forceps lifting base 25 .

The wire engaging portion 25d detachably engages the large-diameter portion 26a (so-called column portion; see FIG. 9 described later) provided at the front end of the operation wire 26.

The wire engaging portion 25d is engaged with the large-diameter portion 26a to hold the tip of the operation wire 26 on the wire pulling portion 25c.

Furthermore, when the operation wire 26 is pulled in a state where the large diameter portion 26a is engaged with the wire engaging portion 25d, the forceps lifts the base due to the traction force transmitted from the large diameter portion 26a to the wire pulling portion 25c through the wire engaging portion 25d. 25 will lift.

In addition, the large-diameter portion 26a and the wire engaging portion 25d may be configured to be rotatable with each other.

The stopper contact surface 25s is a contact surface that comes into contact with the rotation restricting portion 20s of the distal end protrusion 20x described later when the forceps lifting base 25 is rotated within a predetermined rotatable range.

By bringing the stopper contact surface 25s into contact with the rotation restricting portion 20s, the rotation of the forceps lifting base 25 in the lifting direction is restricted.

In addition, the detailed structure and function of the front-end protrusion part 20x including the rotation restriction part 20s with which the stopper contact surface 25s abuts will be described later.

The lift base operating mechanism part 27 and the like including a part of the operating wire 26 are arranged in the third region B3 of the front end structural part main body 20 .

Therefore, the second front end side opening 20 b that is the second opening connected to the operating wire insertion conduit (not shown) that is the conduit that penetrates the insertion part 9 is formed in the third region B3 of the distal end structural part body 20 (see Figure 7, Figure 8).

With this structure, a part of the front end area of the operation wire 26 protrudes from the second front end side opening 20 b of the front end structure body 20 of the front end structure part 6 , and the front end of the operation wire 26 is held by the wire pulling part 25 c.

Furthermore, the operation wire 26 is configured to reciprocate in the direction along the insertion axis Ax according to the operation of the endoscope user.

Here, the front end area of the operation wire 26 , that is, the area between protruding from the second front end side opening 20 b and being held by the wire pulling part 25 c may be provided with a waterproof covering member such as a covering tube.

By providing such a covering tube or the like on at least the portion of the operation wire 26 that is exposed to the outside, the surface of the operation wire, which is mainly made of a metal material, can be protected.

In addition, when the operation wire 26 is lifted up or inverted, the length protruding from the second front end side opening 20b is displaced.

Taking this into consideration, it is conceivable to form the cladding pipe or the like into a structure using a stretchable material or into a corrugated shape.

Furthermore, one end of the covering tube is sealingly bonded to the periphery of the second front end opening 20b.

Similarly, the other end of the covering tube is sealed and bonded to the front end of the operating wire 26 .

With such a structure, the waterproof function of the operating wire 26 can be ensured.

In addition, the operation wire 26 is inserted into the insertion part 9 into an operation wire insertion conduit (not shown) provided between the predetermined operation member from the front end structural part 6 to the operation part 10 .

A part of the front end of the operation wire 26 protrudes outward from the second front end side opening 20 b of the front end structural part 6 .

At this time, as shown in FIG. 9 , the front end of the operation wire 26 has a large diameter portion 26 a whose diameter is enlarged.

Furthermore, the large-diameter portion 26a is engaged with the wire pulling portion 25c.

In addition, the base end of the operation wire 26 is connected to a predetermined operation member of the operation part 10 (not shown).

With this structure, the operation wire 26 reciprocates in the direction along the insertion axis Ax in the operation wire insertion conduit when receiving an operation force from a predetermined operation member of the operation part 10 .

And the driving force generated by this reciprocating motion is transmitted to the forceps lifting base 25 through the wire pulling part 25c.

The driving force transmitted to the forceps lifting base 25 causes the forceps lifting base 25 to rotate around the rotation axis Ax2 within a predetermined rotation range.

In addition, as a structural example of the large-diameter portion 26a of the operation wire 26, as shown in FIG. 9, the large-diameter portion 26a is formed into a substantially cylindrical shape.

However, the shape of the large-diameter portion of the operation wire is not limited to the structural example in FIG. 9 .

For example, the large-diameter portion of the operation wire may be configured as shown in FIG. 10 .

The front end of the operation wire 26A shown in FIG. 10 has a large diameter portion 26Aa formed in a substantially spherical shape.

Such a form can also function exactly the same as the large-diameter portion 26a of the structural example in Fig. 9 .

In addition, a wire pulling portion 25 c formed to protrude from the side surface of the forceps lifting base 25 in a direction substantially perpendicular to the insertion axis Ax is disposed in the third region B3 of the distal end structure body 20 .

In addition, a front end protruding portion 20x constituting a part of the lift base operating mechanism portion 27 is formed in the third region B3 of the front end structural portion main body 20 .

Here, the lift base operation mechanism part 27 refers to a mechanism part composed of the front end protrusion part 20x, the wire pulling part 25c, and the operation wire 26.

The front end protrusion 20x extends toward the front end side with respect to the second front end side opening 20b in the direction along the insertion axis Ax.

The front end protrusion 20x has a guide surface 20g and a rotation restricting portion 20s.

The guide surface 20g is composed of a curved surface that guides the reciprocating motion of the operation wire 26 protruding from the second front end side opening 20b.

The curved surface of the guide surface 20g is formed in a shape along the following trajectory: when the forceps lifting base 25 is in the inverted state, the operation wire 26 extends from the second front end side opening 20b until it is connected to the wire pulling part 25c. traces of.

The rotation restricting portion 20s is provided at one end of the guide surface 20g close to the base end.

The rotation restricting portion 20 s is provided to restrict the rotation angle at which the wire pulling portion 25 c can rotate together with the forceps lifting base 25 due to the pulling force of the operation wire 26 .

That is, the rotation restricting portion 20s comes into contact with the stopper contact surface 25s of the wire pulling portion 25c that rotates together with the forceps lifting base 25 within a predetermined rotation angle range, thereby restricting the forceps lifting base 25 in the lifting direction. of rotation angle.

In addition, the curved surface of the guide surface 20g is formed so as to have a gap between the movement trajectory within the movement range when the wire pulling portion 25c rotates together with the forceps lifting base 25 by the pulling force of the operation wire 26.

This gap is provided to prevent the wire pulling part 25c from coming into contact with parts other than the rotation restricting part 20s.

In such a structure, in the core structural member provided in the third region B3 of the front end structural part body 20, the second front end side opening 20b, the guide surface 20g, the rotation restricting part 20s, and the wire pulling part 25c are arranged along the insertion The line of axis Ax is roughly parallel to the straight line.

In other words, a part of the operation wire 26 protruding from the second distal side opening 20b, the distal protruding portion 20x including the guide surface 20g and the rotation restricting portion 20s, and the wire pulling portion 25c are arranged on a straight line substantially parallel to the line along the insertion axis Ax. superior.

That is, the lifting base operation mechanism part 27 composed of the operation wire 26, the distal protrusion part 20x, and the wire pulling part 25c is provided in a region deviated from the treatment instrument guide range.

Here, the treatment instrument guide range is a range in which the treatment instrument 40 can move in the up, down, left and right directions when viewed from the front end side of the insertion axis Ax when the forceps lifting base 25 is lifted.

This treatment instrument guide range corresponds to a rectangular area indicated by the symbol [A] when viewed from the front of the front end structure part 6 as shown in FIG. 7 , for example.

In addition, the distal end protruding portion 20x (third region B3) and the forceps lifting base 25 (second region B2) are arranged in adjacent regions in the distal end structural portion main body 20.

At this time, the surface of the distal protrusion 20x facing the forceps lifting base 25 is formed smoothly within the range in which the forceps lifting base 25 rotates.

Furthermore, a gap is provided in the portion where the front end protrusion 20x and the forceps lifting base 25 face each other.

The gap in this case is set to have a maximum size smaller than the size of the first front end opening 20a. This is to prevent the treatment tool 40 from being inserted between the front end protrusion 20x and the forceps lifting base 25.

At the same time, by providing a gap smaller than the size of the first distal side opening 20 a, it can be expected that the treatment instrument 40 is guided to the treatment instrument guide portion 25 b side of the forceps lifting base 25 .

In addition, the first front end side opening 20 a and the second front end side opening 20 b are arranged side by side in a direction substantially perpendicular to the insertion axis Ax, that is, in the width direction of the front end structural part body 20 (see FIG. 7 ).

However, in this case, the first front end side opening 20a and the second front end side opening 20b are formed at positions shifted from each other in the direction along the insertion axis Ax.

The front end cover 30 is a cover member attached to the front end side of the front end structural part main body 20 .

The front end cover 30 covers at least a part of the forceps lifting base 25, the operation wire 26, the wire pulling part 25c and the outer surface of the front end protruding part 20x.

Furthermore, the front end cover 30 has an opening 30a, which is used to avoid hindering the movement of the forceps lifting base 25 in the lifting direction due to rotation (see FIGS. 2 to 4).

With this structure, when the forceps lifting base 25 is rotated by the traction force of the operation wire 26, the forceps lifting base 25 operates without contacting the tip cover 30.

The structure of the endoscope 2 of this embodiment is as described above.

In the endoscope 2 configured in this way, the function of the forceps lifting base 25 in the distal end structure part 6 will be described below using FIGS. 3 , 4 and 11 to 16 .

Here, when the traction force of the operation wire 26 is not applied to the forceps lifting base 25, the forceps lifting base 25 is inverted (falls down).

The state at this time is called the inverted state of the forceps lifting base 25 (see FIGS. 2 to 4, 6, 8 to 10, and 15).

On the other hand, when the traction force of the operation wire 26 is applied to the forceps lifting base 25, the forceps lifting base 25 rotates and is lifted.

The state at this time is called the lifted state of the forceps lifting base 25 (see FIGS. 11 to 14 and 16 ).

FIG. 11 is a diagram showing the front-end structural part in the same manner as FIG. 3 .

In addition, FIG. 12 shows a state in which the front end cover is removed from the front end structural part in FIG. 11 .

Figures 11 and 12 show a state in which the pliers lifting base is in the middle of being lifted.

FIG. 13 is a diagram showing the front end structure part in the same manner as FIGS. 3 and 11 .

In addition, FIG. 14 shows a state in which the front end cover is removed from the front end structural part in FIG. 13 .

Figures 13 and 14 show the maximum lifted state of the pliers lifting base.

In addition, in FIGS. 3 , 4 , and 11 to 14 , in order to explain the function of the forceps lifting base itself, a state without a treatment instrument is shown.

On the other hand, FIGS. 15 and 16 show the treatment instrument being lifted up by the action of the forceps lifting base.

Among them, FIG. 15 shows the distal end structure part with the distal end cover removed, and also shows the state in which the treatment instrument is present.

In addition, FIG. 16 shows a state in which, after the state in FIG. 15 , the forceps lifting base is lifted together with the treatment instrument, and the treatment instrument reaches the maximum lifted position.

First, in the endoscope 2 of this embodiment, when the forceps lifting base 25 is not operated, the forceps lifting base 25 is in the inverted state shown in FIGS. 3 and 4 .

At this time, the reciprocating motion of the operation wire 26 stops.

That is, the pulling force of the operation wire 26 is not transmitted to the wire pulling part 25c of the forceps lifting base 25.

Here, a rotational force is applied to the forceps lifting base 25 in the inversion direction R2.

However, the rotation of the forceps lift base 25 in the inversion direction R2 by this rotational force is restricted by the forceps lift base 25 coming into contact with a predetermined portion of the inner surface of the tip cover 30 .

Thereby, the inverted state of FIG. 3 and FIG. 4 is maintained.

When the endoscope user is in the inverted state shown in FIGS. 3 and 4 , the endoscope user operates predetermined operating members of the operating unit 10 to perform a lifting operation on the forceps lifting base 25 .

Upon receiving the lifting operation at this time, the operation wire 26 is pulled toward the operation part 10 in the direction along the insertion axis Ax.

The pulling force of the operation wire 26 is transmitted to the forceps lifting base 25 through the wire pulling part 25c.

Thereby, the forceps lifting base 25 rotates around the rotation axis Ax2 in the predetermined lifting direction R1 from the inverted state in FIGS. 3 and 4 .

Then, the forceps lifting base 25 is displaced to the state shown in FIGS. 11 and 12 , for example.

At this time, while the forceps lifting base 25 is moving in the lifting direction, the wire pulling portion 25c maintains a gap with the guide surface 20g of the front end protruding portion 20x and moves along the guide surface 20g without contacting the guide surface 20g. Surface movement of 20g.

When the lifting operation of the forceps lifting base 25 is continued and the operation wire 26 is continued to be pulled in this state, soon the stopper contact surface 25s of the wire pulling portion 25c of the forceps lifting base 25 and the rotation restricting portion of the front end protruding portion 20x 20s butt.

Thereby, the rotation of the forceps lifting base 25 in the lifting direction R1 is restricted.

The state of the pliers lifting base 25 at this time is the maximum lifting state shown in FIGS. 13 and 14 .

Here, as described above, the rotation of the forceps lifting base 25 is restricted by bringing the stopper contact surface 25s into contact with the rotation restricting portion 20s.

Therefore, the forceps lifting base 25 does not rotate further in the lifting direction R1 from the position shown in FIGS. 13 and 14 .

In addition, the wire pulling portion 25c of the forceps lifting base 25 is configured not to interact with the rotation restricting portion while moving from the inverted state shown in FIGS. 3 and 4 to the maximum lifted state shown in FIGS. 13 and 14 . Partial contact beyond 20s.

Thereby, the forceps lifting base 25 can move smoothly within the predetermined rotation range.

In addition, in the maximum raised state of FIGS. 13 and 14 , the endoscope user operates predetermined operating members of the operating unit 10 to relax the traction force of the operating wire 26 .

This allows the forceps lifting base 25 to be operated upside down.

In this way, the forceps lifting base 25 performs an appropriate lifting operation of pulling the operation wire 26 and an inversion operation of loosening the operation wire 26, so that the operation wire 26 can be reciprocated within a predetermined range (a predetermined rotation angle). Within the range), the lifting position of the pliers lifting base 25 can be set arbitrarily.

In addition, during the reciprocating operation of the operation wire 26, the endoscope user can maintain the stopped position of the operation wire 26 by operating other predetermined operating members of the operation part 10.

Thereby, the forceps lifting base 25 can maintain any stop position within a predetermined movement range.

On the other hand, in a state where the treatment instrument 40 is inserted into the treatment instrument insertion channel 17 of the insertion portion 9 of the endoscope 2 according to this embodiment, the operation of the forceps lifting base 25 is as follows.

First, the treatment instrument 40 is inserted from the forceps insertion opening 11 and inserted into the treatment instrument insertion channel 17 .

Then, the distal end portion of the treatment instrument 40 is brought into a state of protruding from the first distal end opening 20 a of the distal end structure body 20 .

At this time, the pliers lifting base 25 is in an inverted state.

The status at this time is shown in Figure 15.

In the state of FIG. 15 , the endoscope user operates predetermined operating members of the operating unit 10 to lift the forceps lifting base 25 .

Then, upon receiving the lifting operation, the operation wire 26 is pulled toward the operation part 10 in the direction along the insertion axis Ax.

The traction force of the operation wire 26 lifts the forceps lifting base 25 through the wire traction part 25c.

Thereby, the forceps lifting base 25 rotates in the predetermined lifting direction R1 about the rotation axis Ax2.

At this time, the front end portion of the treatment instrument 40 is lifted as the forceps lifting base 25 is rotated in the lifting direction R1.

Furthermore, the protruding direction of the treatment instrument 40 is changed.

When the lifting operation of the forceps lifting base 25 is continued in this state, the treatment tool 40 comes into contact with the insulating block 24 soon.

Thereby, the movement of the treatment instrument 40 in the lifting direction and the rotation of the forceps lifting base 25 in the lifting direction R1 are restricted.

The state of the treatment instrument 40 and the forceps lifting base 25 at this time is as shown in FIG. 16 .

At this time, the treatment instrument 40 cannot move further in the lifting direction from the position shown in FIG. 16 .

In addition, the forceps lifting base 25 will not rotate further in the lifting direction from the position shown in FIG. 16 .

In addition, in this state, the stopper contact surface 25s of the forceps lifting base 25 does not come into contact with the rotation restricting portion 20s of the distal end protrusion 20x.

In this way, when the treatment instrument 40 is inserted into the insertion portion 9 and the front end portion of the treatment instrument 40 protrudes from the front end structure body 20, the treatment instrument 40 lifted by the forceps lifting base 25 comes into contact with the insulating block 24, thereby limiting The movement range of the treatment tool 40 is determined.

As described above, according to the above-described embodiment, the endoscope of the forceps lifting base 25 is provided with the forceps lifting base 25 for changing the protruding direction of the treatment instrument 40 protruding outward from the first distal end side opening 20a of the distal end structure part 6 of the insertion part 9 In the mirror 2, the forceps lifting base 25 has a wire pulling portion 25c formed to protrude from the side in a direction substantially perpendicular to the insertion axis Ax.

In addition, the tip protruding portion of the tip structure portion 6 has a guide surface 20g that guides the reciprocating motion of the operation wire 26 and a rotation restriction portion 20s that restricts the rotation angle at which the wire pulling portion 25c can rotate together with the forceps lifting base 25.

The rotation restriction part 20s is provided at the end part of the guide surface 20g.

By adopting such a structure, in the distal end structure portion 6 of the endoscope 2 according to the present embodiment, the rotation restriction portion 20 s for restricting the rotation of the forceps lifting base 25 can be provided on the slave treatment instrument in the distal end structure portion main body 20 The position of the boot range offset.

Therefore, with this structure, for example, when the treatment instrument 40 is inserted or removed, the treatment instrument 40 does not get caught on the rotation restricting part 20s or the like.

Therefore, good operability of the endoscope 2 and the treatment instrument 40 can always be ensured.

In addition, in the above-mentioned embodiment, a partition wall is not provided between the forceps lifting base and the forceps lifting base operating mechanism, and a mechanism is used that connects the forceps lifting base to the operating wire and directly pulls the forceps lifting base.

In this structure, for example, the forceps lifting base and the mechanism part for operating the forceps lifting base are arranged in each space separated by a wall member or the like. Compared with the structure of the present invention, not only the component structure can be simplified, but also the number of components can be reduced.

Therefore, it can contribute to the reduction of manufacturing costs required for cutting processing of the front-end structural part main body 20 etc., assembling each structural component, etc.

In addition, the wire pulling part 25c is integrally formed and protrudes from the side of the forceps lifting base 25, and the second front end side opening 20b, the guide surface 20g, the rotation restricting part 20s, and the wire pulling part 25c are respectively provided along the insertion direction. on the straight line of axis Ax.

With this structure, the operation wire 26 protruding from the second front end side opening 20b extends linearly without being bent, and is held by the wire pulling portion 25c.

Therefore, there is no need for bending processing of the operation wire 26 required in the conventional structure, which can contribute to improvement in assembly workability and improvement in durability of the operation wire 26 .

The wire pulling part 25c is formed to have a surface integrally connected with the treatment instrument guide part 25b of the forceps lifting base 25.

With this structure, for example, when the treatment instrument 40 is inserted and removed, the treatment instrument 40 will not get stuck on structural parts such as the wire pulling part 25c.

Therefore, there is an effect of suppressing interference with the operability of the endoscope 2 and the treatment instrument 40 .

The guide surface 20g of the front end protrusion 20x is formed by a curved surface protruding from the second front end side opening 20b and formed along the trajectory of the operation line 26 extending forward.

With this structure, the operation wire 26 does not come into contact with the front end protrusion 20x (curved surface), and the forceps lifting base 25 can be rotated smoothly.

In addition, this curved surface is formed to have a gap from the wire pulling part 25c.

With this structure, the wire pulling part 25c, which moves as the forceps lifting base 25 rotates, avoids contact with parts other than the rotation restricting part 20s within its movement range.

With this structure, smooth rotation of the forceps lifting base 25 can be maintained.

In the distal structure portion of the endoscope according to the above-described embodiment, rotation restriction when the forceps lifting base is in an inverted state is achieved by bringing the forceps lifting base into contact with a predetermined portion of the inner surface of the distal end cover.

In a modification of the distal end structural portion of the endoscope of the present embodiment described below, a structural example is shown in which a rotation restricting portion in the inverted direction of the forceps lifting base is provided in the distal end structural portion.

FIG. 17 is a diagram showing a modified example of the distal end structural portion of the endoscope according to the embodiment of the present invention.

In addition, FIG. 17 shows a state in which the front end cover is removed, similarly to FIG. 4 and so on.

The basic structure of the front end structure part of the modified example shown in FIG. 17 is substantially the same as that of the above-mentioned embodiment.

In this modification, only the structures of the front end protruding portion 20Bx provided on the front end structure body 20B and the wire pulling portion 25Bc provided on the forceps lifting base 25B are slightly different from the front end structure portion of the above-described one embodiment.

Therefore, the same structures as those in the above-described embodiment are denoted by the same reference numerals and their detailed description is omitted, and only the different parts will be described in detail below.

As shown in FIG. 17 , the distal end protrusion 20Bx provided in the distal end structure body 20B of the distal end structure in this modification example is similar to the distal end protrusion 20x in the above-described one embodiment, along the insertion axis Ax. direction extending toward the front end side than the second front end side opening 20b.

Moreover, the front-end protrusion part 20Bx has the guide surface 20g, the 1st rotation restriction part 20sa (1st contact part), and the 2nd rotation restriction part 20sb (2nd contact part).

Like the above-described embodiment, the guide surface 20g is formed of a curved surface that guides the reciprocating motion of the operation wire 26 protruding from the second front end opening 20b.

The first rotation restricting portion 20sa is provided at one end of the guide surface 20g close to the base end.

That is, the first rotation restricting portion 20sa corresponds to the rotation restricting portion 20s in the above-described embodiment.

Therefore, the first rotation restricting portion 20sa comes into contact with a predetermined portion (the first portion; the first stop contact surface 25sa) of the wire pulling portion 25Bc that rotates together with the forceps lifting base 25, thereby restricting the position of the forceps lifting base 25B. The angle of rotation in the lifting direction.

In other words, when the forceps lifting base 25B is in the maximum lifted state, the first rotation restricting portion 20sa (first contact portion) contacts the first stopper contact surface 25sa (first portion) of the wire pulling portion 25Bc, The rotation of the pliers lifting base 25B in the lifting direction is restricted.

The second rotation restricting portion 20sb is provided at the other end portion near the front end of the guide surface 20g.

The second rotation restricting portion 20sb comes into contact with a predetermined portion (second portion; second stopper contact surface 25sb) of the wire pulling portion 25Bc that rotates together with the forceps lifting base 25, thereby restricting the inversion of the forceps lifting base 25B. The angle of rotation of the direction.

In other words, the second rotation restricting portion 20sb (second contact portion) comes into contact with the second stopper contact surface 25sb (second portion) of the wire pulling portion 25Bc when the forceps lifting base 25B is in the inverted state. The rotation of the pliers lifting base 25B in the inverted direction is restricted.

Corresponding to this front end protrusion 20Bx, the first stopper contact surface 25sa (first part) and the second stopper contact surface 25sb ( The second part) are formed in different locations.

Here, the first stopper contact surface 25sa corresponds to the stopper contact surface 25s in the above-described embodiment.

Therefore, when the forceps lifting base 25B moves in the lifting direction, the first stop contact surface 25sa comes into contact with the first rotation restricting portion 20sa, thereby restricting the rotation of the forceps lifting base 25B in the lifting direction.

In addition, when the forceps lifting base 25B moves in the inversion direction, the second stopper contact surface 25sb comes into contact with the second rotation restricting portion 20sb, thereby restricting the rotation of the forceps lifting base 25B in the inversion direction.

Other structures are the same as the above-mentioned embodiment.

In this modified example configured in this way, a mechanism (second rotation restricting portion 20sb and second stopper contact surface 25sb) for restricting the rotation of the forceps lifting base 25B in the inversion direction is further provided.

With this structure, rotation can be restricted reliably in both the lifting direction and the inversion direction of the forceps lifting base 25B.

Therefore, the movement range of the forceps lifting base 25B can be reliably defined.

The endoscope shown in the above-mentioned embodiment can be applied to a so-called reusable endoscope that can be used repeatedly by performing cleaning and sterilization operations after use, and can also be used after being used only once. Just discarded disposable endoscopes.

In particular, when applied to disposable endoscopes, it is expected to contribute to further reduction in manufacturing costs.

In addition, in the distal end structure part of the endoscope according to the above embodiment, when inserting the treatment instrument into the insertion part to perform a predetermined treatment, as described above, the distal end of the treatment instrument is moved from the first end of the distal end structure part. The front end side opening protrudes outward.

At this time, there is a possibility that due to the bending state of the insertion portion of the endoscope, etc., the front end of the treatment instrument moves in a direction deviating from the guide surface of the forceps lifting base, and the front end of the treatment instrument may penetrate into the forceps lifting base. in the gap between the seat or operating wire and the inner surface of the front cover.

In such a case, when the treatment instrument is stuck inside the front end structure, the treatment instrument cannot be further advanced.

When such a situation occurs, unnecessary operations such as temporarily pulling out the treatment instrument and re-inserting the treatment instrument have to be performed, which degrades the operability of the endoscope or the treatment instrument. reason.

There are various types of treatment instruments used in combination with this endoscope.

However, no matter what kind of treatment instrument is used, it is preferable that the treatment instrument is configured to be able to move forward and backward smoothly in the vicinity of the forceps lifting base.

Therefore, in the distal structure part 6 of the endoscope 2 of this embodiment, the inner surface shape of the distal cover 30 is considered so that the treatment instrument 40 can be always used without being caught near the forceps lifting base 25. A structure that advances and retreats smoothly.

18 to 21 are diagrams schematically illustrating the distal end structure of the endoscope according to one embodiment of the present invention.

Among them, FIG. 18 is a diagram schematically showing the appearance of the front-end structural part in the endoscope according to this embodiment.

FIG. 19 shows a cross section along line [18] to [18] in FIG. 18 .

FIG. 20 shows a cross section along the plane indicated by arrow [20] in FIG. 19 .

FIG. 21 shows a cross section along line [21] to [21] in FIG. 18 .

Here, in the front end structure part 6 , the direction along the insertion axis Ax is defined as the X axis, and the two axes perpendicular to the X axis are defined as the Y axis and the Z axis respectively.

Among them, the Y-axis is the width direction of the front-end structural part 6, and the Z-axis is the up-and-down direction of the front-end structural part 6 (refer FIG. 19 to FIG. 21).

As described above, the distal structural portion 6 in the insertion portion 9 of the endoscope 2 is composed of the distal structural portion main body 20 and the distal end cover 30 .

Among them, the front end structural part main body 20 and each structural component mounted on the front end structural part main body 20 are as described above.

In addition, as mentioned above, the front end cover 30 is a cover member attached to the front end side of the front end structural part main body 20 .

Here, the tip cover 30 covers at least a part of the forceps lifting base 25, the operation wire 26, the wire pulling part 25c, and the outer surface of the tip protrusion 20x.

Furthermore, the tip cover 30 is provided with an opening 30 a that allows the forceps lifting base 25 to be in a lifted state when the forceps lifting base 25 is rotated.

On the inner surface of the tip cover 30, a treatment instrument guide surface 31 is formed in a smooth curved surface continuously connected to the side wall surface near the forceps lifting base 25 and the opening 30a of the tip cover 30.

Here, for example, as shown in FIG. 20 , the treatment instrument guide surface 31 preferably sets the angle An1 of the side wall surface of the front end cover 30 in the X-axis direction (that is, the direction in which the treatment instrument 40 advances to the front end side) to approximately 150°. Obtuse angle of about degrees.

Furthermore, for example, as shown in FIG. 21 , the treatment instrument guide surface 31 preferably sets the angle An2 of the side wall surface of the front end cover 30 in the Z-axis direction that is substantially perpendicular to the X-axis (that is, the direction in which the treatment instrument 40 is lifted). An obtuse angle of about 145 degrees.

By forming the treatment instrument guide surface 31 based on this preferred setting on the inner surface of the front end cover 30, when the treatment instrument 40 is advanced to the front end side in the inverted state of the forceps lifting base 25, or when the treatment instrument 40 is passed through the forceps lifting base 25, 25 When the treatment instrument 40 is lifted, the front end of the treatment instrument 40 can be smoothly guided in the direction of the opening 30a of the front end cover 30.

Therefore, with such a structure, in the distal end structure portion 6 of the endoscope 2 according to the present embodiment, the treatment instrument 40 can always advance and retreat smoothly without being stuck near the forceps lifting base 25 .

Furthermore, when the treatment instrument 40 is inserted and removed, the treatment instrument 40 does not get stuck in the front end cover 30 , and the treatment instrument 40 can always be inserted and removed smoothly.

Furthermore, for example, when the endoscope 2 is used, even if solid residues or the like in the body cavity enter the inside of the distal structural portion 6 through the opening 30 a of the distal cover 30 or the like, the inner surface of the distal cover 30 is formed It has a smooth shape, so these solid residues are easily discharged to the outside.

In addition, the shape of the inner surface of the distal end cover 30 is not limited. For example, the portion between the inner surface of the distal end cover 30 and the treatment instrument guide portion 25 b of the forceps lifting base 25 may be formed to be connected by a smooth curved surface. In this case, the same effect can be further obtained.

The present invention is not limited to the above-described embodiments, and various modifications and applications can be made without departing from the gist of the invention.

Furthermore, the above-described embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining the plurality of disclosed structural elements.

For example, even if some structural elements are deleted from all the structural elements shown in the above embodiments, the problem to be solved by the invention can be solved. If the effect of the invention can be obtained, the structure with the structural elements deleted can be regarded as the invention. extract.

Furthermore, structural elements of different embodiments may also be combined appropriately.

The present invention is not limited by the specific embodiments except as defined by the appended claims.

Claims (17)

1. An endoscope, comprising: A front-end structural part provided at the front-end part of the insertion part inserted into the subject; a forceps lifting base, which is configured to be freely rotatable relative to the front end structural part and used to lift the treatment instrument protruding from the first opening provided in the front end structural part; An operating wire protrudes from the second opening provided in the front end structure part and performs reciprocating motion in the length direction of the insertion part; A wire pulling portion is formed to protrude from the pliers lifting base in a direction intersecting the length direction, holds the front end of the operation wire, and transmits the traction force generated by the reciprocating motion of the operation wire to the operation wire. the pliers lifting base; and A front-end protruding portion is provided on the front-end structural portion and has a guide surface and a limiting portion. The guide surface guides the reciprocating motion of the operating wire. The limiting portion is provided at an end of the guide surface. part for limiting the rotation angle that the wire pulling part can rotate together with the pliers lifting base. 2. The endoscope according to claim 1, wherein, The front end protrusion extends toward the front end side relative to the second opening in the length direction. 3. The endoscope according to claim 2, wherein, The second opening, the guide surface, the restriction part and the wire pulling part are respectively provided on straight lines along the length direction. 4. The endoscope according to claim 1, wherein, The restricting portion limits the rotation angle of the forceps lifting base by contacting the wire pulling portion that rotates together with the forceps lifting base within a predetermined rotation angle range. 5. The endoscope according to claim 4, wherein The restriction part has at different positions from each other: a first abutment part that abuts the first part of the wire pulling part when the pliers lifting base is in a lifted state; and a second abutment part, It abuts the second part of the wire pulling part that is different from the first part when the pliers lifting base is in an inverted state. 6. The endoscope according to claim 1, wherein The forceps lifting base has a contact surface that contacts the treatment instrument to guide the treatment instrument, The wire pulling portion is provided at a position away from the contact surface in a direction intersecting the longitudinal direction. 7. The endoscope according to claim 6, wherein The pliers lifting base and the wire pulling part are integrally formed. 8. The endoscope according to claim 7, wherein The wire pulling part has a surface integrally connected with the contact surface of the pliers lifting base. 9. The endoscope according to claim 1, wherein, The guide surface of the front end protrusion is a curved surface. 10. The endoscope according to claim 9, wherein The curved surface is formed in a shape along a trajectory from when the pliers lifting base is in an inverted state from when the operation wire extends from the second opening to connecting with the wire pulling part. traces of. 11. The endoscope according to claim 9, wherein The curved surface is formed with a gap between the wire pulling portion and the wire pulling portion so as to avoid the wire pulling portion from coming into contact with the restriction within a range in which the wire pulling portion moves together with the rotational action of the pliers lifting base. contact with other parts. 12. The endoscope according to claim 1, wherein The front end of the operation wire has a large diameter portion with an enlarged diameter, The wire pulling portion has a wire engaging portion that detachably engages the large-diameter portion, When the operation wire is pulled in a state where the large diameter portion is engaged with the wire engaging portion, the pulling force transmitted from the large diameter portion to the wire pulling portion through the wire engaging portion is utilized. Lift the pliers lifting base. 13. The endoscope according to claim 1, wherein The first opening and the second opening are respectively arranged at different positions across one surface of the front end protrusion. 14. The endoscope according to claim 1, wherein The surface of the front end protrusion facing the forceps lifting base is formed smoothly within a range in which the forceps lifting base rotates. 15. The endoscope according to claim 1, wherein The portions of the front end protrusion and the forceps lifting base that face each other are configured to have a gap with a maximum dimension smaller than the size of the first opening. 16. The endoscope according to claim 1, wherein The endoscope further has a front end cover, which is installed on the front end structural part and covers the forceps lifting base, the operating wire, the wire pulling part and the front end protruding part. 17. The endoscope of claim 1, wherein The endoscope is a disposable endoscope that is used only once and then discarded.