JP5628661B2 - Endoscope - Google Patents

Description

  The present invention relates to an endoscope provided with an objective optical unit and an illumination optical unit at a circular tubular tip.

  In recent years, endoscopes are used in the medical field and the industrial field. Endoscopes used in the medical field can be observed by inserting an elongated insertion portion into the body, and various treatments can be performed by inserting a desired treatment instrument into a treatment instrument insertion channel as necessary.

  On the other hand, endoscopes used in the industrial field can inspect for scratches, corrosion, and the like by inserting an elongated insertion portion into a boiler, a gas turbine engine, piping of a chemical plant, an automobile engine, or the like.

  In an endoscope, it is desired to reduce the diameter of the insertion portion. For example, Patent Literature 1 discloses an intra-body cavity observation device. In this body cavity observation apparatus, an illumination unit is provided with an observation unit interposed therebetween, and a shape in which a light guide that constitutes the illumination unit and a lens barrel holding unit are combined is configured in a cylindrical shape. In this body cavity observation apparatus, it is possible to obtain and observe with sufficient illumination light as well as realizing a reduction in diameter.

  Further, in Patent Document 2, the outer shape of the insertion part is formed by forming the light guide emission end provided at the tip of the rigid endoscope in a substantially crescent shape, compared to the case where the emission end is formed in a circular shape with the same area. It is shown that the diameter can be reduced.

JP 2002-136473 A Japanese Patent Laid-Open No. 08-122663

  However, in an endoscope used in the industrial field, the observation object is a metal, and the insertion portion moves on the metal surface. For this reason, in the endoscope of Patent Document 1, the illumination ends of the illumination units arranged symmetrically are arranged close to the metal surface of the observation unit, and thus halation occurs and hinders observation. There was a risk.

  On the other hand, in the endoscope of Patent Document 2, halation is prevented and good observation can be performed by separating the substantially crescent-shaped emission end from the metal surface. However, in this endoscope, since the thickness from the observation window end opposite to the exit end to the outer periphery of the tip is thin, wear occurs due to repeated movement of the insertion section on the metal surface. There was a risk of causing trouble.

  In addition, when a retaining pin is disposed as a means for preventing the members constituting the insertion portion of the endoscope from falling off, the retaining pin is reduced in size as the diameter of the insertion portion is reduced. There arises a problem that it becomes difficult and assembly work becomes difficult.

  The present invention has been made in view of the above circumstances, and is an endoscope that prevents the problem of observation due to halation and the problem of observation that occurs when the insertion part is worn while reducing the diameter of the insertion part. The purpose is to provide.

  An endoscope according to an aspect of the present invention includes a distal end cover member that forms a distal end exterior of an endoscope insertion portion having a circular outer shape and a through hole coaxial with a central axis thereof, and a through hole of the distal end cover member. A frame that has the same inner diameter and diameter and is inserted through the through-hole, and a lens arrangement hole in which a lens constituting the objective lens group is arranged, and a frame coaxial with the central axis of the outer shape of the large-diameter portion A through-hole, and an arc-shaped bottom surface formed around the central axis of the large-diameter portion provided in the large-diameter portion on one side of a horizontal line perpendicular to the optical center of the lens fixed to the lens arrangement hole A lens frame member having a light guide installation recess, and a plurality of optical fibers that guide illumination light are bundled, and an inner peripheral surface and an outer peripheral surface that are arranged and fixed on the arc-shaped bottom surface of the lens frame member on the distal end side. Having semi-circular or combination A light guide bundle having a light guide tip formed so as to be configured in a semicircular tube; the light guide bundle disposed in the tip cover member; and the lens frame member inserted and disposed in a through hole of the tip cover member. A drop-off prevention mechanism that prevents the drop-out.

An endoscope according to another aspect of the present invention is configured by bundling a plurality of optical fibers that guide illumination light, and has a light guide distal end portion formed on the distal end side so as to form a semicircular tube or a semicircular tube in combination. And a plurality of lenses disposed on the front surface of the solid-state imaging device that constitutes the objective optical unit. A lens arrangement hole provided, a circle formed to be recessed in the outer circumferential direction on one side from the imaginary line orthogonal to the optical center of the lens arranged in the lens arrangement hole, and the inner circumferential surface of the light guide tip portion being arranged A light guide installation portion having an arc-shaped bottom surface, and a frame front end portion formed by cutting out a predetermined position of the outer peripheral surface of the front end portion on the other side from the imaginary line to provide a flat surface and a rising surface Structure by being integrally fixed and the lens frame member, the light guide tip the lens frame member arranged on the light guide installation portion provided in the lens frame member that consists in a circular tubular member having a And a first surface on which the flat surface provided on the lens frame member is provided and a rising surface provided on the inner surface of the through-hole in which the observation part set to be arranged is disposed. A distal end cover member that constitutes an exterior of the endoscope insertion portion in which the central axis of the outer shape and the central axis of the through hole are concentric.

  ADVANTAGE OF THE INVENTION According to this invention, the endoscope which prevented the malfunction of the observation by halation and the malfunction of the observation which generate | occur | produces when the insertion part wears is realizable, aiming at diameter reduction of an insertion part.

The figure explaining an endoscope system Front view for explaining the distal end surface of the distal end portion of the endoscope Y3-Y3 sectional view of FIG. The figure explaining a lens frame and the light guide front-end | tip part installed in a lens frame Front view of an observation unit configured by fixing a light guide tip to a light guide installation recess of a lens frame and an imaging frame Observation unit perspective view Diagram showing observation state with reduced halation Diagram showing an unsuitable observation state due to halation It is a figure explaining the other structure of a drop-off prevention mechanism part, Comprising: The figure explaining the front-end | tip part of a structure provided with a hole in a front-end | tip cover member and a convex part in a lens frame. The figure explaining the excision part formed in a lens frame The figure explaining the state which has penetrated the lens frame in the through-hole of the front-end | tip cover member The figure explaining the structure which leaves a convex part in the large diameter part of a lens frame The figure explaining the state which has arrange | positioned the observation part group by which the light guide front-end | tip part was fixed to the lens frame which has a convex part in the through-hole of the front-end | tip cover member. It is a figure explaining another structure of a drop-off prevention mechanism part, Comprising: A figure explaining the front-end | tip part of a structure provided with the crimping protrusion in a front-end | tip cover member, and the recessed part formed in the lens frame by the notch part. Front view for explaining a state in which a caulking portion is provided at the tip of the tip cover member and the tip cover member and the lens frame are integrally fixed Y14-Y14 sectional view of FIG.

Embodiments of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, an endoscope system 1 includes an endoscope 10 having an elongated insertion portion 2, and an apparatus main body 30 to which a universal cord 4 extending from an operation portion 3 of the endoscope 10 is connected. It is configured with.

  The insertion portion 2 includes, in order from the distal end side, a distal end portion 2a, a bending portion 2b configured to be able to be bent in the vertical direction, and a flexible tube portion 2c formed in a long shape having flexibility. Configured. An imaging device (not shown) having an imaging element such as a C-MOS is built in the distal end portion 2a.

The operation section 3 is provided with a bending operation lever 3a for performing an operation for bending the bending section 2b. The arrangement position of the bending operation lever 3a is provided so that it can be rotated when the operation unit 3 is placed on a desk surface or a work table surface. The finger rest portion 3 b provided on the bending operation lever 3 a coincides with the upward direction of the insertion portion extending from the operation portion 3. The bending portion 2b is configured to bend in a bending upward direction that is an upward direction of the insertion portion 2 or a bending downward direction that is a downward direction of the insertion portion 2 in accordance with a turning operation of the bending operation lever 3a.
In addition to the bending operation lever 3a, the operation unit 3 is provided with various switches 3c for instructing various imaging operations of an imaging device provided in the distal end portion 2a, for example.

The apparatus main body 30 is provided with a monitor 31 that displays an endoscopic image captured by the imaging apparatus. Inside the housing 32 of the apparatus main body 30, an image processing CPU, an electrical component (not shown) such as a recording device for recording a processed image, a light source device (not shown) for supplying illumination light, and a power supply are supplied. A battery unit (not shown) and the like are disposed.
The power of the battery is supplied to the imaging device, the monitor 31, electric components, a light source device, and the like.

  In the universal cord 4, a signal cable connected to the imaging device, a light guide bundle (hereinafter abbreviated as LG bundle) for transmitting illumination light of the light source device, and the like are inserted.

The configuration of the tip 2a will be described with reference to FIGS.
As shown in FIGS. 2 and 3, the distal end portion 2 a includes a distal end cover member 5, a lens frame member (hereinafter abbreviated as a lens frame) 6, an LG bundle 7, and an imaging frame 8. Yes. The LG bundle 7 is an illumination optical unit configured by bundling a plurality of optical fibers that guide illumination light.

An illumination window portion 70 and a tip lens 11 are provided on the tip surface of the tip portion 2a.
The illumination window part 70 is an opening for emitting the illumination light emitted from the LG bundle 7 to the outside. In the present embodiment, the illumination window portion 70 is a substantially U-shaped opening, and is configured by combining the lens frame 6 and the tip cover member 5. A light guide tip 7a, which will be described later, is disposed in the illumination window 70. And the front end side space of the illumination window part 70 is filled with transparent resin, for example. An illumination lens may be disposed instead of the transparent resin.

The front lens 11 has a circular shape, and is fixed to a first lens arrangement hole 6 h 1 formed in the lens frame 6. In the present embodiment, the optical center of the tip lens 11 disposed on the lens frame 6 and the center axis of the outer shape of the tip cover member 5 are coaxial and the center axis 2aA of the tip portion 2a.
Reference numeral 5ah denotes a D-shaped hole, which is a D-shaped observation portion arrangement hole. In the D-shaped hole 5ah, a frame front end portion 6c of a lens frame 6 and a light guide front end portion 7a of the LG bundle 7 constituting an observation unit set 9 to be described later are arranged.

  The lens frame 6 shown in FIGS. 3 and 4 is made of a metal member. The lens frame 6 is tubular and includes a large diameter portion 6a and a small diameter portion 6b, and a frame through hole 6h. The large-diameter portion 6a is the maximum outer shape portion of the lens frame 6, is configured with a predetermined diameter D, and is divided into a frame front end portion 6c and a frame main body 6d by a step portion 6e. The central axis of the outer shape of the large diameter portion 6a and the small diameter portion 6b and the central axis of the frame through hole 6h are coaxial.

  As shown in FIG. 3, for example, lens arrangement holes 6h1, 6h2, and 6h3 are provided in the frame through hole 6h for arranging various lenses constituting the objective lens group. The front lens 11 is fixed in the first lens arrangement hole 6h1, the optical lenses 12 and 13 are fixed in the second lens arrangement hole 6h2, and the optical lenses 14 and 15 are fixed in the third lens arrangement hole 6h3. Has been. And the optical axis of each lens 11-15 is in agreement.

  As shown in FIGS. 2 and 4, on the outer peripheral surface side of the large diameter portion 6a, there is a light guide installation recess 6f having an arcuate bottom surface 6f1 and a frame tip portion forming plane (hereinafter abbreviated as a tip plane) 6g1. A notch 6g is provided.

  The light guide installation recess 6f is provided on one side of the horizontal line HL which is a virtual line orthogonal to the central axis 2aA which is also the optical center of the tip lens 11 shown in FIG. 2, and the notch 6g sandwiches the light guide HL. It is provided on the other side of the installation recess 6f.

  Specifically, as shown in FIGS. 2 and 4, the light guide installation recess 6f is provided on the outer periphery on the upper side in the drawing, which is one side from the horizontal line HL, and the radius of the arcuate bottom surface 6f1 is set to R. The central axis of the arc-shaped bottom surface 6f1 and the central axis of the large diameter portion 6a are coaxial.

  On the other hand, the notch 6g is provided on the outer periphery on the lower side in the figure which is the other side from the horizontal line HL. The tip flat surface 6g1 constituting the notch 6g is set to a plane parallel to the horizontal line HL.

And the step part 6e which has the standing surface 6e1 is comprised by the large diameter part 6a by having formed the notch part 6g in the large diameter part 6a. And the frame front-end | tip part 6c divided by the step part 6e becomes a substantially D-shaped cross-sectional external shape.
Note that the upper side in the figure from the horizontal line HL is the upward direction of the insertion portion 2, in other words, the upward direction of the bending portion 2b.

  As shown in FIG. 4, the light guide tip 7a of the LG bundle 7 is disposed in the light guide installation recess 6f. The light guide tip 7a is formed by molding the tip of the LG bundle 7 into a predetermined shape. In the present embodiment, the light guide distal end portion 7a is molded into a semicircular tube having a concentric outer peripheral surface 7c and inner peripheral surface 7d. The outer peripheral radius of the semicircular tubular light guide distal end portion 7a is set to R1 which is half of the diameter D of the large diameter portion 6a or shorter than that, and the inner peripheral radius is the same as the radius R of the arcuate bottom surface 6f1, Alternatively, the length is set longer, and the length is set shorter than the length from the front end of the lens frame 6 to the base end of the imaging frame 8 as shown in FIG.

  The light guide tip 7a is not limited to a semicircular tube shape, and is divided into a first light guide tip 7a1 and a second light guide tip 7a2 as shown in FIGS. They may be combined to form a semicircular tube shape. Further, the number of divisions is not limited to two and may be more than that. Reference numeral 7b denotes an emission surface.

  As shown in FIG. 3, the imaging frame 8 includes a through hole 8h, and the through hole 8h includes a connecting hole 8h1 and an imaging hole 8h2. The connection hole 8h1 is externally fitted to the outer peripheral surface of the small diameter portion 6b of the lens frame 6. The imaging hole 8h2 mainly includes a prism 8a that is an optical reflecting member, a protective member 8b, an imaging element 8c, and a substrate 8e on which an electronic component 8d and the like are mounted. The protection member 8b is bonded to the reflection surface of the prism 8a. The imaging element 8c is bonded to the lower surface of the prism 8a, and the imaging surface is arranged in parallel to the central axis 2aA.

  The imaging frame 8 performs focus adjustment and is integrally fixed to the lens frame 6 to constitute an objective optical unit. As a result, the optical image that has entered the prism 8a after passing through the objective lens group included in the lens frame 6 is bent by the prism 8a and formed on the imaging surface of the imaging element 8c.

The protective member 8b is made of the same material as the prism 8a, or a transparent glass member having the same linear expansion coefficient (thermal expansion coefficient) with light transmission, or a synthetic resin or metal member having no light transmission. Etc. are formed. The prism 8a and the protection member 8b are joined by a reflecting surface, and are configured as one block body in which the peripheral shapes of all the upper and lower side portions are the same. In the present embodiment, the prism 8a and the protection member 8b are fixed to the inner surface of the imaging hole 8h2 so that the prism 8a is firmly fixed to the imaging frame 8.
The image sensor 8c is electrically connected to the substrate 8e. Reference numeral 8f is a sealing resin.

As shown in FIGS. 5 and 6, the inner peripheral surface 7d of the light guide distal end portion 7a is disposed on the arc-shaped bottom surface 6f1 of the light guide installation recess 6f, and is integrally fixed to the lens frame 6 by adhesion, so that the observation unit Set 9 is formed. Reference numeral 6e1h is a communication hole. The communication hole 6e1h communicates the second lens arrangement hole 6h2 of the frame through hole 6h with the outside.
A light guide installation recess (not shown) similar to the light guide installation recess 6 f of the lens frame 6 is provided on the outer peripheral surface of the imaging frame 8.

  As shown in FIGS. 2 and 3, the tip cover member 5 constitutes an exterior. The tip cover member 5 has a through hole 5h that is coaxial with the central axis of the circular outer shape. A thick-walled portion 5a for forming a circular tip side opening of the tip cover member 5 into a substantially D-shaped tip side opening is provided on the inner surface of the through hole 5h.

The thick portion 5a includes a first surface 5a1 that is an installation surface and a second surface 5a2 that is an abutment surface, and a front end plane 6g1 that constitutes the lens frame 6 is installed on the first surface 5a1, and the second surface 5a1 is installed. A rising surface 6e1 is disposed in contact with the surface 5a2. That is, the through-hole 5h is an inner periphery of the D-shaped hole 5h1 constituting the distal end side of the through-hole provided with the thick portion 5a and the through-hole 5h constituting the proximal end side from the second surface 5a2 of the thick portion 5a. And a circular hole 5h2 as a surface. The inner diameter of the circular hole 5h2 is set to the same size as the diameter D of the large diameter portion 6a constituting the lens frame 6.
The second surface 5a2 and the rising surface 6e1 constitute a drop-off prevention mechanism.

Here, assembly of the distal end portion 2a of the endoscope 2 will be described.
The distal end portion 2 a of the endoscope 2 is configured by arranging the observation portion set 9 in the through hole 5 h of the distal end cover member 5. The operator inserts the distal end side of the observation unit set 9 from the proximal end side of the through hole 5 h of the distal end cover member 5. Then, the outer peripheral surface of the large diameter portion 6 a comes into contact with the inner peripheral surface of the through hole 5 h of the tip cover member 5. And the frame front-end | tip part 6c is arrange | positioned in the D-shaped hole 5h1, and the frame main body 6d is arrange | positioned in the circular hole 5h2. At this time, the standing surface 6e1 contact | abuts to the 2nd surface 5a2 of the thick part 5a. As a result, the observation unit set 9 is positioned at a predetermined position with respect to the lens frame 6. Thereafter, the operator applies an adhesive between the lens frame 6 and the tip cover member 5 to fix the lens frame 6 and the tip cover member 5 integrally.

  According to the endoscope 2 configured with the distal end portion 2a configured as described above, the optical axis of the lens 11-15, the outer axis of the distal end cover member 5, and the axis of the through hole 5h are coaxial, and the lens frame. The optical axis of the lens 11-15 disposed in the frame through hole 6h of the lens frame 6 is set so that the diameter of the outer peripheral surface of the large diameter portion 6a is the same as the inner diameter of the circular hole 5h2 of the through hole 5h. And the central axis of the outer shape of the tip cover member 5 are coaxial. In addition, the light guide tip 7a of the LG bundle 7 is disposed on one side of the optical axis of the lens 11-15.

  For this reason, as shown in FIG. 7, in the state where the illumination light emitting end 10a is separated from the observation target surface 20 with the tip lens 11 in between, the illumination light is located above the optical axis of the lens 11-15. The light is emitted from the unit 70. As a result, it is possible to secure a distance from the illumination light emitting end 10a to the observation target surface 20 and reduce halation. If the tip portion 2a is disposed upside down as shown in FIG. 8, the insertion portion is rotated 180 degrees at the maximum. As a result, the arrangement state of the distal end portion 2a of the endoscope 10 can be corrected to the state shown in FIG. 7 to reduce halation.

  Also, a thick part 5a is provided at the tip of the tip cover member 5, a notch 6g is provided in the large diameter part 6a of the lens frame 6, and a notch 6g is provided in the second surface 5a2 of the thick part 5a. Thus, the rising surface 6e1 of the stepped portion 6e is configured to abut. As a result, it is possible to reliably prevent the lens frame 6 from dropping from the frame through hole 6h of the tip cover member 5, and it is possible to increase the wear resistance of the tip portion 2a of the insertion portion 2.

  Further, the optical axis of the lens 11-15 disposed in the frame through-hole 6h of the lens frame 6 and the center of the outer shape of the tip cover member 5 are set concentrically, and the light guide tip 7a is moved to the lens 11-15. By arranging the drop-off prevention part mechanism on the other side from the optical axis, it is possible to effectively utilize the vacant space and realize a configuration in which the tip part 2a has the smallest diameter. it can.

  In addition, according to the endoscope 10 described above, when the insertion unit 2 is arranged along the observation target surface 20 in a state where the operation unit 3 is placed on the desk surface, for example, the illumination light emitting end 10a is located on the observation target surface. In this configuration, the thick portion 5a is disposed on the observation target 20 side.

  For this reason, when the endoscope usage environment is such that the insertion unit 2 is simply inserted into the target site and the inspection is performed along the observation target surface 20, the user can move the top and bottom of the distal end of the insertion unit with respect to the observation target surface 20. Since the relationship can be intuitively grasped while the operation unit 3 is held, the usability can be improved. In addition, the position of the illumination light emitting end 10a with respect to the observation target surface 20 and the position of the thick portion 5a are configured in advance in consideration of a frequently used situation when the operation unit 3 is held. For this reason, the user can perform an efficient inspection by inserting and removing the insertion portion without considering halation or wear due to contact with the observation target surface 20, that is, without worrying about the state of the insertion portion tip. It can be carried out.

  In the above-described embodiment, the imaging surface of the imaging element 8c is arranged in parallel to the central axis 2aA. However, a configuration in which the imaging surface of the imaging element 8c is arranged so as to be orthogonal to the central axis 2aA may be employed.

  Further, the drop-off preventing mechanism for preventing the lens frame 6 from dropping from the frame through-hole 6h of the tip cover member 5 is limited to the configuration in which the rising surface 6e1 is brought into contact with the second surface 5a2. is not.

  For example, as shown in FIG. 9A, a dropout prevention hole 5b that connects the through hole 5h and the outside is provided at a predetermined position of the tip cover member 5, and the dropout prevention hole 5b is engaged at a predetermined position of the large diameter portion 6a of the lens frame 6. Protruding portions 6j to be placed are provided. The convex part 6j is a structure which does not protrude from the outer peripheral surface of the lens frame 6 in the state arrange | positioned at the drop-off prevention hole 5b.

  In this configuration, the protrusion amount of the convex portion 6j is set to X. And between the protrusion amount X of the convex part 6j and the distance (D / 2-R) from the circular-arc-shaped bottom face 6f1 which forms the light guide installation recessed part 6f of the lens frame 6 to the inner peripheral surface of the front-end | tip cover member 5. Set the relationship to X <(D / 2-R). 9B, the side portion of the lens frame 6 is cut off by a predetermined distance L. The shaded portion is the cut portion 6k. Accordingly, the lens frame 6 is set to be movable (D / 2-R) within the through hole 5h.

In this configuration, the tip 2a is assembled in the following procedure.
That is, the operator inserts the lens frame 6 into the through hole 5h of the tip cover member 5 as indicated by an arrow Y9 in FIG. Then, the convex portion 6 j of the lens frame 6 is dropped into the dropout prevention hole 5 b of the tip cover member 5. Thereafter, the operator integrally fixes the lens frame 6 and the tip cover member 5 by adhesion, for example.

Next, the operator arranges the light guide distal end portion 7 a of the LG bundle 7 in a space portion formed by the inner peripheral surface of the distal end cover member 5 and the light guide installation concave portion 6 f of the lens frame 6. After the placement, the operator adheres and fixes the light guide tip 7 a to the inner peripheral surface of the tip cover member 5 and the arc-shaped bottom 6 f 1 of the lens frame 6.
By this, the front-end | tip part of the endoscope which has the effect | action and effect similar to embodiment mentioned above can be comprised.

  Further, in order to arrange the lens frame with high accuracy with respect to the through hole of the tip cover member, as shown in FIG. 10, the light guide installation concave portion is left so that the contact convex portion 6m remains on the large diameter portion 6a of the lens frame 6A. In addition to providing 6f, a light guide installation recess 8f may be provided so that the projection 8g remains in the imaging frame 8A.

  In this configuration, the light guide installation recess 6f of the lens frame 6 is configured to be divided into a first light guide installation recess 6fA and a second light guide installation recess 6fB, and the diameter of the outer peripheral surface of the contact projection 6m. Is the same size as the large diameter portion. The light guide installation recess 8f of the imaging frame 8 is also configured to be separated into a first light guide installation recess (not shown) and a second light guide installation recess 8fB.

Then, the light guide installation recesses 6fA, 8fA, the light guide installation recess 6fB, and the light guide installation recesses (not shown) of the imaging frame 8 are arranged with light guide tip portions 7a1 corresponding to the shapes of the respective light guide installation recesses The observation unit 9A is configured by being fixed by bonding. In the present embodiment, the light guide distal end portion 7a is formed in a semicircular tube shape by the two light guide distal end portions 7a1 and the contact convex portion 6m disposed between the light guide distal end portions 7a1.
Other configurations are the same as those of the above-described embodiment, and the same members are denoted by the same reference numerals and description thereof is omitted.

  According to this configuration, when the observation unit set 9A is disposed in the through hole 5h of the tip cover member 5, the outer peripheral surface of the large diameter portion 6Aa of the lens frame 6A is the inner peripheral surface of the through hole 5h as shown in FIG. And the outer peripheral surface of the contact protrusion 6m contacts the through hole 5h.

  As a result, the lens frame 6 </ b> A can be quickly and accurately arranged with respect to the tip cover member 5. As a result, the lens 11 and the light guide distal end portion 7a1 are accurately arranged at predetermined positions with respect to the distal end cover member 5, and the best endoscopic image can be obtained.

  As shown in FIGS. 11 and 12, a caulking protrusion 5 c that protrudes by a predetermined amount is provided at a predetermined position at the tip of the tip cover member 5. On the other hand, as shown in FIGS. 10 to 12, the lens frame 6A is provided with a notch 6gA at a predetermined position on the front end surface of the lens frame 6A to receive a caulking projection 5c.

  Then, after the lens frame 6A is disposed in the through hole 5h of the tip cover member 5, the crimping protrusion 5c is caulked, the tip cover member 5, and the lens frame 6A so as to be accommodated in the recess formed by the notch 6gA. Are fixed together.

  In this way, by fixing the tip cover member 5 and the lens frame 6A by caulking, it is possible to reliably prevent the lens frame 6A from falling off the tip cover member 5. As a result, the structure of the tip cover member 5 can be simplified, and the component cost and manufacturing cost can be reduced.

  Note that the integral fixing of the tip cover member 5 and the lens frame 6A is not limited to the caulking fixing by the caulking projection 5c. For example, as shown in FIGS. The crimping process may be performed to provide a crimping portion 5d so that the tip cover member 5 is integrally fixed to the lens frame 6A. The caulking portion 5d is formed so that the distal end portion of the distal end cover member 5 is pressed and arranged in the notch portion 6gA of the lens frame 6A.

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

DESCRIPTION OF SYMBOLS 1 ... Endoscopy system 2 ... Insertion part 2a ... Tip part 2b ... Bending part
2c ... Flexible tube part 2aA ... Center axis 3 ... Operation part 3a ... Bending operation lever 3b ... Finger rest part 3c ... Switch 4 ... Universal cord
5 ... tip cover member 5a ... thick part 5a1 ... first surface 5a2 ... second surface
5b ... Fall-off prevention hole 5c ... Caulking protrusion 5d ... Caulking part 5h ... Through hole
5h1 ... D-shaped hole 5h2 ... circular hole 6, 6A ... lens frame 6Aa ... large diameter portion 6a ... large diameter portion 6b ... small diameter portion 6c ... frame tip 6d ... frame main body 6e ... step portion 6e1 ... rising surface 6e1h ... Communication hole 6f ... Light guide installation recess 6f1 ... Arc bottom 6fA ... First light guide installation recess
6fB: second light guide installation recess 6g, 6gA ... notch 6g1 ... tip flat surface 6h ... frame through hole 6h1 ... first lens placement hole 6h2 ... second lens placement hole
6h3 ... 3rd lens arrangement hole 6j ... Convex part 6k ... Cut part 6m ... Contact convex part
7 ... LG bundle 7a, 7a1, 7a2 ... Light guide tip 7b ... Outgoing surface
7c ... Outer peripheral surface 7d ... Inner peripheral surface 8, 8A ... Imaging frame 8a ... Prism
8b ... Protective member 8c ... Image sensor 8d ... Electronic component 8e ... Substrate
8f: Light guide installation recess 8fB: Light guide installation recess 8g ... Projection
8h ... through hole 8h1 ... connecting hole 8h2 ... imaging hole 9, 9A ... observation part set
DESCRIPTION OF SYMBOLS 10 ... Endoscope 10a ... Illumination light emission end 11 ... End lens
12, 13, 14, 15 ... optical lens 20 ... observation target surface 30 ... main body of apparatus
31 ... Monitor 32 ... Exterior housing 70 ... Lighting window

Claims (9)

A distal end cover member constituting the distal end exterior of the endoscope insertion portion having a circular outer shape and having a through hole coaxial with the central axis;
The inner diameter and the diameter of the through hole of the tip cover member are the same size, and a large diameter part that is inserted and arranged in the through hole, and a lens arrangement hole in which a lens constituting the objective lens group is arranged are provided. A frame through hole that is coaxial with the central axis of the outer shape, and a central axis of the large-diameter portion provided on the large-diameter portion on one side of the horizontal line perpendicular to the optical center of the lens fixed to the lens arrangement hole A lens frame member having a light guide installation recess having an arc-shaped bottom surface formed in
A plurality of optical fibers that guide illumination light are bundled together, and a semicircular tube having an inner peripheral surface and an outer peripheral surface that are arranged and fixed on the arcuate bottom surface of the lens frame member on the front end side, or a semicircular tube that is combined with each other. A light guide bundle having a light guide tip formed so as to be disposed in the tip cover member;
A drop-off prevention mechanism for preventing the lens frame member inserted through the through hole of the tip cover member from dropping off;
An endoscope comprising:   The endoscope according to claim 1, wherein an optical center of the lens and a central axis of the tip cover member are coaxial.   The endoscope according to claim 1, wherein a part of the large-diameter portion of the lens frame member is disposed in contact with the inner peripheral surface of the through hole of the tip cover member.   2. The length of a hard length to be molded at a light guide front end portion of the light guide bundle is set to be shorter than a length from a front end of the lens frame to a base end of an imaging frame. Endoscope. The drop-off prevention mechanism portion is configured by providing a cutout portion on the other side of the horizontal line of the large-diameter portion provided with the light guide installation recess, and a rising surface provided on the lens frame member;
The abutment provided on the inner surface on the distal end side of the through hole of the distal end cover member, wherein the rising surface formed in a thick portion that makes the circular distal end side opening a substantially D-shaped distal end side opening is abutted and disposed Surface,
The endoscope according to claim 1, further comprising: The drop-off prevention mechanism is
A convex portion projecting at a predetermined projection amount at a predetermined position on the outer peripheral surface of the lens frame member;
A drop-off prevention hole that is formed at a predetermined position of the tip cover member and in which the convex portion is disposed,
Consisting of
The protrusion amount of the convex portion is smaller than the distance from the arc-shaped bottom surface of the light guide installation concave portion of the lens frame member to the inner peripheral surface of the tip cover member in a state where the lens frame member is assembled in the through hole. The endoscope according to claim 1, wherein the endoscope is set. The drop-off prevention mechanism is
A caulking protrusion protruding at a predetermined position of the tip of the tip cover member;
A concave portion provided by a notch at a predetermined position on the distal end surface side of the distal end portion of the lens frame member;
2. The endoscope according to claim 1, wherein the caulking protrusion is caulked so as to be accommodated in the concave portion to prevent the lens frame member from dropping from the tip cover member. 3. A plurality of light guide installation recesses are provided on one side of a horizontal line orthogonal to the optical center of the lens fixed in the lens arrangement hole of the large diameter portion of the lens frame member,
The endoscope according to claim 1, wherein a convex portion having an outer peripheral surface having the same size as the diameter of the large diameter portion is provided between the adjacent light guide installation concave portions. A light guide bundle having a light guide tip portion formed by bundling a plurality of optical fibers that guide illumination light, and shaped to form a semicircular tube or a semicircular tube in combination on the tip side;
A lens arrangement hole in which a plurality of lenses arranged on the front surface of a solid-state imaging device constituting the objective optical unit are fixedly formed by a tubular member having the same outer diameter as the outer diameter of the semicircular tubular guide guide. A light guide having an arcuate bottom surface that is formed to be recessed in the outer peripheral direction on one side of the imaginary line orthogonal to the optical center of the lens disposed in the lens disposition hole, and in which the inner peripheral surface of the light guide tip is disposed A lens frame member comprising: an installation portion; and a frame tip formed by notching a predetermined position of the outer peripheral surface of the tip on the other side from the imaginary line to provide a flat surface and a rising surface;
Observation unit set is arranged constituted by being integrally fixed to the lens frame member by arranging the light guide end portion in the light guide installation portion provided in the lens frame member that consists in a circular tubular member And a meat having a first surface on which the flat surface provided on the lens frame member is installed and a second surface on which the rising surface is installed. A distal end cover member that constitutes an exterior of the endoscope insertion portion that includes a thick portion, and the center axis of the outer shape and the center axis of the through hole are concentric;
An endoscope comprising:

Images