JPH06130308A - Optical adapter of endoscope - Google Patents

Abstract

PURPOSE:To provide the optical adapter for the endoscope which enables secure and easy attachment and detachment, maintain safety so as to prevent a fall at the time of mounting, and has a small increase in the external diameter of the endoscope insertion part. CONSTITUTION:When the optical adapter 31 is mounted on the endoscope tip part 9, the optical adapter is turned in its circumferential direction to engages a lock pin 35 with a groove 22, and then restrained from moving axially. In this engagement state, a rotation restraint pin 40 which is energized by a pressure spring 38 is fitted in and engaged with a recessed part 23. Consequently, the adapter 31 is restrained from rotating in the circumferential direction. Then the state wherein the adapter 31 is restrained from rotating in the circumferential direction with the energizing force is held. The rotation restraint pin 40 and recessed part 23 are disengaged from each other with the energizing force of the pressure spring 38 and the adapter 31 is turned in the circumferential direction and detached from the tip part 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an optical adapter for an endoscope having an attaching / detaching mechanism that can be attached to and detached from a tip portion of the endoscope.

[0002]

2. Description of the Related Art In recent years, by inserting an elongated insertion portion into a body cavity, the organ in the body cavity can be observed and, if necessary,
2. Description of the Related Art Endoscopes that can perform various therapeutic treatments using a treatment instrument inserted in a treatment instrument channel are widely used.

Boilers, gas turbine engines,
BACKGROUND ART Industrial endoscopes are widely used for observing and inspecting scratches and corrosion inside pipes of chemical plants and the body of automobile engines.

Further, as the endoscope, in addition to the fiber type optical endoscope, various electronic endoscopes using a solid-state image pickup device such as a charge coupled device (CCD) as an image pickup means are also used.

By the way, in an endoscope having a structure in which an optical adapter is detachably attached to the tip of the insertion portion, the tip of the insertion portion to which the optical adapter is attached is inserted into a body cavity or a duct or the like. It is necessary to completely prevent falling.

Conventionally, as a mechanism for attaching and detaching the distal end of the insertion portion of the endoscope and the optical adapter, screw portions provided to each other are screwed together.

Japanese Utility Model Publication No. 61-21043 discloses a structure in which an optical adapter is attached to and detached from the tip of the endoscope body. In the one described in this publication, the distal end portion of the endoscope insertion portion is rotatably and externally threaded,
A ring-shaped member that is locked in the axial direction is inserted. On the other hand, the optical adapter is provided with a female screw at a portion fitted to the ring-shaped member and is screwed and assembled to the ring-shaped member.

Further, the optical adapter has a pin which engages with an L-shaped groove formed in the distal end portion so that the optical adapter is locked at the distal end portion to prevent the optical adapter from falling off. That is, it is a loosening prevention in the screwed state.

Further, the observation optical path and the illumination optical path can be matched only when the front end portion and the optical adapter are completely fastened.

[0010]

As described above, since the distal end of the insertion portion is inserted into the body cavity or the duct, it is necessary to completely prevent the optical adapter from falling off.

For this reason, in the one described in the above publication, in order to make the optical adapter detachable, a rotatable ring member is provided on the outer periphery of the distal end portion of the endoscope, and the ring member and the optical adapter are provided respectively. The screw part is screwed and fixed. Further, the pin of the optical adapter is engaged with the L-shaped groove formed at the tip portion to lock the optical adapter at the tip portion. These pins and grooves serve as a mechanism for preventing them from coming off.

[0012] However, in the case where the threaded portion is screwed like the conventional one, the wall thickness of each is increased by the amount of forming the screw, and the outer diameter of the endoscope insertion portion is increased accordingly. . Further, in the one described in the above publication, since the ring member fitted to the distal end portion and the optical adapter are screwed together, the diameter of the endoscope insertion portion is increased by the amount of the ring member, and there is room for improvement. There is.

The present invention has been made in view of the above circumstances, and ensures secure and easy attachment / detachment and safety so as to prevent falling off during attachment, and a large outer diameter of an endoscope insertion portion. It is an object of the present invention to provide an optical adapter for an endoscope that is less likely to be used.

[0014]

SUMMARY OF THE INVENTION The present invention is an optical adapter for an endoscope which is removably provided at the tip of an endoscope insertion portion, wherein the optical adapter is provided at the tip by rotating in the circumferential direction. A movement restricting member that engages with the first engaging portion and restricts movement in the axial direction, and is slidable in the axial direction, and is engaged with the first engaging portion and the movement restricting member. The rotation restricting member that restricts rotation in the circumferential direction by engaging and engaging with the second engaging portion of the tip portion in the combined state, and the rotation restricting member And a biasing unit that holds the state in which the rotation in the circumferential direction is restricted by biasing toward the engaging portion.

[0015]

[Operation] According to the present invention, when the optical adapter is mounted on the distal end portion of the endoscope, the adapter is rotated in the circumferential direction so that the movement restricting member engages with the first engaging portion provided on the distal end portion. And regulate the movement of the adapter in the axial direction.

With the first engaging portion engaged with the movement restricting member, the rotation restricting member urged toward the second engaging portion by the urging means is moved to the second engaging portion. Engage and engage the part. As a result, the rotation of the adapter in the circumferential direction is restricted. Then, since the rotation restricting member is biased toward the second engaging portion by the biasing force of the biasing means, the state in which the circumferential rotation of the adapter is restricted is maintained. That is, the optical adapter is prevented from rotating and dropping from the tip portion.

On the other hand, the force against the urging force of the urging means releases the engagement between the rotation restricting means and the second engaging portion, and the adapter is rotated in the circumferential direction. It becomes a state. Then, in the released state, the adapter is rotated in the circumferential direction to remove the adapter from the tip portion.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 relate to a first embodiment of the present invention, FIG. 1 is a cross-sectional view of a distal end of an endoscope with an optical adapter attached, FIG. 2 is an overall configuration diagram of an endoscope system, and FIG. It is a perspective view which looked through an adapter and a tip part of an endoscope.

As shown in FIG. 1, the endoscope system 1 includes
It is composed of a fiber type endoscope 2 and a light source device 3 which supplies illumination light to an observation target through the endoscope 2.

The endoscope 2 has an elongated and flexible insertion section 4, a large-diameter operation section 5 connected to the rear end of the insertion section 4, and a rear end of the operation section 5. And an eyepiece section 6 which is provided. A flexible universal cord 7 is extended laterally from the operation portion 5, and a connector 8 is provided at an end portion of the universal cord 7. This connector 8
Are connected to the light source device 3.

The insertion section 4 comprises, in order from the tip side, a hard tip section 9, a bendable bending section 10, and a flexible tube section 11 which is flexible and is connected to the operation section 5.

An optical adapter 31 is detachably attached to the tip portion 9. The optical adapter 31 is an adapter that is attached to the direct-viewing endoscope 1 so that the field of view can be changed to the side-viewing type.

The bending portion 10 is bent by operating the operation knob 12 provided on the operation portion 5.

FIG. 1 shows a cross section of the tip of the insertion portion.
The tip portion 9 has a tip forming member 14, and the tip forming member 14 is provided with an illumination window, an observation window, and a forceps channel port (not shown) on its tip surface.

A light distribution lens 15 is mounted inside the illumination window, and an emission end of a light guide 16 made of a fiber bundle is arranged at the rear end of the light distribution lens 15. The light guide 16 is inserted through the insertion portion 4, the operation portion 5 and the universal cord 7 and connected to the connector 8. Illumination light emitted from a light source lamp (not shown) in the light source device 3 is incident on the incident end of the light guide 16.

Inside the observation window, the incident ends of the objective optical system 17 and the image guide fiber 18 are
They are arranged in order. The exit end of the image guide fiber 18 is arranged in the eyepiece section 6 so that an endoscopic image can be observed at the eyepiece section 6.

At the rear end of the tip forming member 14, there is provided a bending tube in the bending portion 10 which is composed of a large number of substantially cylindrical joint pieces 20, ... Have,
The outer peripheral portion of this curved tube is covered with a curved rubber 21. Further, the rear end of the rearmost joint piece is fixed to the flexible tube 11.

A gravitational direction detector 19 is fixed to a rear end of the tip forming member 14. The gravity direction detector 19 detects the direction of gravity at the tip of the endoscope.

Further, an L-shaped groove 22 as a first engaging portion with which a pin of the optical adapter 31 described later is engaged is formed on the outer peripheral surface of the tip forming member 14.
As shown in FIG. 3, the L-shaped groove 22 is formed parallel to the axial direction from the outer peripheral tip of the tip portion 9 toward the rear, and is further bent at a right angle to the axial direction.

A concave portion 23 as a second engaging portion with which a pin of the optical adapter 31 described later is engaged is axially provided on the distal end surface of the distal end constituting member 14.

On the other hand, the optical adapter 31 has an adapter body 32 formed in a substantially cylindrical shape, and the adapter body 32 is held by the adapter body 32, and the adapter 31 is attached to the tip 9.
And a lever portion 33 for restricting the rotation of the lever.

The adapter body 32 has a fitting hole 32a formed at the rear end thereof for fitting with the tip 9, and an observation / illumination window 32 is formed from the side surface to the center of the fitting hole 32a.

The observation / illumination window 32 partially communicates with the fitting hole 32a, and the bottom portion thereof is formed obliquely with respect to the axial direction. A mirror 34 is attached to the bottom.

On the inner peripheral surface of the fitting hole 32a, a locking pin 35 as a first movement restricting means for engaging with the L-shaped groove 22 of the tip portion 9 is provided in a protruding manner. Then, by rotating the optical adapter 31 until the locking pin 35 reaches the terminal end 22a of the L-shaped groove 22 of the tip portion 9, the optical adapter 31 is locked to the tip portion 9. In this state,
The optical adapter 31 is restricted from moving in the axial direction.

With the optical adapter 31 attached to the tip portion 9, the mirror 34, the objective optical system 17 and the light distribution lens 15 are arranged to face each other. That is, the illumination light can be emitted in a direction perpendicular to the axial direction of the optical adapter 31, and an object in the same direction can be observed.

Further, the adapter body portion 32 axially penetrates a mounting hole 32c into which the lever portion 33 is inserted. Further, a fixing pin 39 is projectingly fixed to the front surface of the main body 32.

The lever portion 33 is a rotation regulating pin 40 as a rotation regulating means which is fitted in the recess 23 of the tip portion 9.
And the head 3 with the tip of the rotation regulating pin 40 fixed
6 and 6. The rotation restricting pin 40 is inserted and held in the mounting hole 32c, and the lever portion 33 is slidably movable in the axial direction.

A cap 37 is fixed to the mounting hole 32c of the adapter body 32 through an opening at the tip end thereof so that the rotation restricting pin 40 is slidably inserted in the axial direction. In the mounting hole 32c, the rotation restricting pin 40 has a pressing spring 38 as a biasing means interposed between a flange formed near the rear end of the rotation restricting pin 40 and the cap 37. One end of the pressing spring 38 is fixed to the cap 37 by adhesion or the like. The biasing means may be a leaf spring or the like, and any means other than the spring may be used as long as it can hold the biasing force.

The rotation restricting pin 40 has the mounting hole 32.
In the state that the flange is inserted into
c is contacted with a step portion formed midway on the rear end side,
Is regulated so as not to move axially backward. The rotation restricting pin 40 is axially pressed by the pressing spring 38, and the tip of the rotation restricting pin 40 projects toward the mounting hole 32c and fits into the recess 23.

Further, the adapter body 32 fixes a fixing pin 39 projecting to the tip end surface at a position substantially opposite to the mounting hole 32c. Further, the lever portion 33 has a locking hole 36a axially formed at a position substantially opposite to the rotation restricting pin 40 so as to engage with the fixed pin 39.

Further, the lever portion 33 is formed with a recess 36b on the outer peripheral surface for hooking a finger to move the lever portion 33 itself forward and backward. That is, the engagement between the rotation restricting pin 40 and the mounting hole 32c is released by hooking a finger or the like on the recess 36b and applying a force against the biasing force of the pressing spring 38.

An explanation of the attachment / detachment mechanism will be given with reference to FIGS. 3 (a) and 3 (b).
This will be described with reference to. The fixing pin 39 of the adapter body 32 is engaged with the locking hole 36a, and is assembled so that the lever 33 does not rotate about the pin 40 as a central axis. The rotation restricting pin 40 of the lever portion 33 is held slidably in the axial direction with respect to the adapter body portion 32, and is attached to the attachment hole 32c of the adapter body portion 32 by the pressing spring 38. It is pushed axially rearward. Therefore, the tip of the pin 40 projects toward the mounting hole 32c side of the adapter body 32. Further, the rotation restricting pin 40 causes the pressing spring 38 to
The fixing pin 39 is formed in such a length that it does not come off from the locking hole 36a even if it moves forward in the axial direction against.

First, as shown in FIG. 3 (a), the optical adapter 31 in which the lever portion 33 and the adapter body portion 32 are combined as described above is inserted into the endoscope distal end portion 9 and rotated clockwise. Let At this time, the tip 9 has an L-shaped groove 22 cut in the axial direction so that the locking pin 35 of the adapter body 32 is guided along the L-shaped groove 22. Locking pin 3
5 is before reaching the L-shaped corner of the groove 22, the rotation regulating pin 40
Has its end abutted against the tip surface of the tip 9 and retracted into the mounting hole 32c.

At the positions of the rotation restricting pin 40 and the recess 23, the locking pin 35 engaged with the L-shaped groove 22 is substantially at the end 2.
When they reach 2a, they agree. Therefore, at this time, the rotation restricting pin 40 is projected by the urging force of the pressing spring 38 and fitted into the recess 23. In this way, the rotation regulating pin 40 regulates the rotation of the optical adapter 31 in the circumferential direction. Further, at the terminal end 22a of the L-shaped groove 22, the locking pin 35 restricts the sliding of the optical adapter 31 in the axial direction.

In this state, the optical adapter 31 is locked to the tip portion 9 and there is no risk of falling off. In addition, the pin 3
The rotation of the lever portion 33 is restricted by the engagement between the engagement hole 9 and the engagement hole 36a.

In the mounted state, the illumination light emitted from the light distribution lens 15 is reflected by the mirror 34 and travels in the direction perpendicular to the axial direction. The reflected light from the subject is guided to the objective optical system 17 via the mirror 34, and is transmitted to the eyepiece 6 by the image guide fiber 18 as an image of the subject.

Next, the case where the optical adapter 31 is removed from the tip 9 will be described.

On the other hand, the concave portion 36b of the head 36 is pulled with a finger in the Z direction shown in FIG. 3 (b), and the optical adapter 31 is rotated in the opposite direction to the assembling, that is, counterclockwise. In this way, the rotation restriction of the optical adapter 31 can be released by removing the fitting between the rotation restriction pin 40 and the recess 36b. Then, in this state, the optical adapter 31 can be removed along the L-shaped groove 22.

In this embodiment, the tip 9 and the optical adapter 3 are
Without forming a screw part to be screwed to
The optical adapter 31 can be detachably combined. That is, in the present embodiment, the optical adapter 31 can be removed from the tip end portion 9 by rotating with the recess 36b provided in the lever 33 hooked with a finger or the like and pulled forward. In the present embodiment, the distal end portion 9 and the optical adapter 31 are not provided with a threaded portion as in the prior art, and the ring-shaped member is not provided. The optical adapter can have a small diameter. And, by the diameter reduction,
The insertability of the endoscope insertion portion can also be improved.

4 and 5 relate to the second embodiment of the present invention. FIG. 4 is a sectional view of the tip of the endoscope with an optical adapter attached, and FIG. 5 is a sectional view for explaining removal of the optical adapter. It is a figure.

In the second embodiment, the operation of the rotation regulating pin 40 of the first embodiment is performed by an electromagnetic solenoid. Other configurations and operations similar to those of the first embodiment are designated by the same reference numerals and description thereof will be omitted.

The optical adapter 45 shown in FIG. 4 is, like the optical adapter 31 shown in FIG. 1, attached to the direct-viewing type endoscope 1 so that the field of view can be changed to the side-viewing type.

The optical adapter 45 is used for the endoscope tip portion 9
The mounting hole 45a penetrates in the axial direction at a position facing the recess 23. The mounting hole 45a has a small diameter from the rear end side opening to the middle, and has a large diameter from the middle to the tip opening. A rotation restriction pin 46 made of a ferromagnetic material is axially slidably held at the rear end of the mounting hole 45a. The rotation regulating pin 46 has its stepped portion in contact with the stepped portion of the mounting hole 45a to limit the axially rearward movement position.

A hollow coil 47 having a hollow interior is fixed to the large diameter portion of the mounting hole 45a.
The rotation restricting pin 46 as the rotation restricting means is arranged so as to be housed in the hollow portion of the hollow coil 47. The hollow coil 47 is sealed by a cap 49 attached to the tip side opening of the attachment hole 45a.

The rotation restricting pin 46 has a rear end connected to a pressing spring 48 as an urging means, and the spring 48 is connected to the rear end surface of the cap 49.
Therefore, the rotation restricting pin 46 is biased axially rearward by the pressing spring 48 to project from the fitting hole 32a.

The coil of the hollow coil 47 is connected to the electrodes 49a and 49b embedded in the cap 49 made of an insulating material. The electrode 49a is exposed on the front surface of the cap 49, while the electrode 49b is connected to the body member of the metallic adapter 45, and this body member serves as the other electrode.

With the above structure, the optical adapter 45 is attached to the endoscope distal end portion 9. The functions of the locking pin 35 and the groove 22 are as described in the first embodiment.

With the locking pin 35 reaching the end 22a of the groove 22, the battery 50 is connected to the electrodes 49a and 49b as shown in FIG. The hollow coil 47 generates a magnetic flux, and the rotation restricting pin 46 made of a ferromagnetic material causes the coil 4 to rotate.
7 is drawn into the hollow portion. As a result, the rotation regulating pin 46 and the recess 23 are disengaged from each other, and the optical adapter 4
It can be removed from the tip 9 by turning 5.

In this embodiment, since a battery is required for removing the optical adapter, unlike the first embodiment, the lever is not accidentally caught on the object to be inspected and the optical adapter does not come off, which is safer. The rest of the configuration, functions and effects are the same as those of the first embodiment, and the explanation is omitted.

As a modification of the second embodiment, the pressing coil 48 is formed of a shape memory alloy while the hollow coil 47 is excluded, and the current applied to the spring 48 is turned ON / OF.
You may make it carry out F and may obtain the same effect.

6 and 7 relate to the third embodiment of the present invention. FIG. 6 is a sectional view of the tip of the endoscope with an optical adapter attached, and FIG. 7 is a sectional view for explaining the removal of the optical adapter. It is a figure.

In the third embodiment, the operation of the rotation regulating pin is performed by an air cylinder. Other configurations and operations similar to those of the second embodiment are designated by the same reference numerals and description thereof will be omitted.

The optical adapter 51 shown in FIG. 6 has an air supply hole 52 which opens from the middle of the mounting hole 45a in the axial direction toward the outer peripheral surface and opens on the outer peripheral surface. That is, the mounting hole 45a communicates with the outside via the air supply hole 52. Further, a cap 53 having a vent hole 53a penetrating therethrough is mounted and fixed on the tip opening side of the mounting hole 45a so as to communicate with the air supply hole 52. Then, the mounting hole 45a
Form a cylinder (hereinafter referred to as cylinder 45a).

The cylinder 45a holds a rotation restricting pin 54 as a rotation restricting means slidable in the axial direction. The head 54a of the rotation regulating pin 54
Is formed to have a size close to the mounting hole 45a. The rotation restriction pin 54 constitutes a piston with respect to the mounting hole 45a which is a cylinder.

The rotation restricting pin 54 has a cylinder 45a.
The pin is biased by an internal pressing spring 48 so as to project axially rearward from the mounting hole 32a.

When air is blown from the air supply hole 52 from the air nozzle 55, the pin 54 moves forward like a piston as shown in FIG. Then, the pin 54 is housed in the main body member of the optical adapter 51, and the engagement between the rotation regulating pin 54 and the recess 23 of the tip portion 9 is released. When assembling, the air supply should be stopped. In this way, the optical adapter 31 is attached to and detached from the tip portion 9.

The rest of the configuration, operation, and effects are the same as in the first embodiment, so a description thereof will be omitted.

FIGS. 8 to 11 relate to the fourth embodiment, FIG. 8 is a sectional view showing a state in which an optical adapter is attached to the distal end portion of the endoscope, and FIG. 9A is a sectional view taken along the line AA of FIG. 9B is a sectional view taken along the line BB in FIG. 8, and FIG. 10 is a view taken in the direction of the arrow D in FIG.
FIG. 11 is another configuration diagram of the fall prevention wire.

The fourth embodiment shows the structure of the attachment / detachment mechanism for the direct-view type endoscope and the direct-view type optical adapter. Regarding the configuration and operation similar to those of the first embodiment,
The same reference numerals are given and the description is omitted.

In this embodiment, the endoscope 1 shown in FIG.
Is configured as an electronic endoscope. An endoscope-side objective optical system 62 and a CCD 63 are arranged at the tip portion 9 of this electronic endoscope in order from the tip side of the observation window. The image formed by the objective lens system 62 is converted into an electric signal by the CCD 63, converted into a TV signal by a camera control unit (not shown), and an image is displayed by a TV monitor (not shown).

Further, a fall prevention wire 71 is fixed to the component member 72 of the tip end portion 9 by brazing or the like so that the fall prevention wire 71 can be recovered even if it is dropped from the insertion portion. The opposite end of the fall prevention wire 71 is fixed inside the operation portion 5. By thus providing the drop-prevention wire, it is possible to prevent the tip end portion 9 of the endoscope from falling off due to being caught when the endoscope is removed from the object to be inspected. Further, although the endoscope distal end portion 9 is mainly assembled with an adhesive material, it is possible to prevent the distal end portion 9 from falling off due to a decrease in adhesive force due to a high temperature environment or a change with time.

Further, as shown in FIG. 11, a non-metallic fall prevention cable 74 may be passed through a U-shaped metal fitting 73 fixed to the constituent member 72 of the tip portion 9 by brazing or the like. The opposite end of the cable 74 is fixed to the operation unit 5. The cable 74 may be made of high-strength fiber such as aramid fiber or carbon fiber.

Next, the optical adapter 64 of this embodiment shown in FIG. 8 will be described below.

The optical adapter 64 has the tip portion 61.
It is detachably attached. The optical adapter 64 has an adapter-side objective optical system 67 arranged at a position facing the endoscope-side objective optical system 62 when it is attached to the distal end portion 9.

The optical adapter 64 is on the side opposite to the adapter-side objective optical system 67, and has a notch shape from the front end to the rear halfway.

Adapter body 65 of this optical adapter 64
Is an insertion hole 6 that opens at a position facing the recess 23.
6 is penetrated in the axial direction, and the insertion hole 66 is opened at the rear end surface of the notch. In addition, the adapter body 65
A holding member 67 having a conduit is fixed to the notch at the tip end side thereof by adhesion or the like.

Between the holding member 67 and the insertion hole 66, a rotation regulating pin 68 having flanges 68a and 68b formed in the middle is supported so as to be slidable in the axial direction. The rotation restricting pin 68 has a pressing spring 69 as an urging means mounted between the flange portion 68 a and the fixing member 67. The pin 68 is biased axially rearward by a pressing spring 69 so as to project from the rear end surface of the adapter 64.

The rotation restricting pin 68 has a flange portion 68.
The outer diameters a and 68b do not project to the outer circumference of the adapter body 65.

The principle of attachment / detachment of the optical adapter 64 is the same as that shown in FIG. A space of approximately 1 mm is provided between the flange portions 68a and 68b, and as shown in FIG. 8, for example, by pushing the pin 68 in the D direction with the tip of the pencil 70,
It can be stored in the adapter body 65. In this state, the optical adapter 64 can be removed along the L-shaped groove 22 shown in FIG.

As described above, in this embodiment, the sliding mechanism including the rotation restricting pin 68 is provided on the inner surface rather than the outer periphery of the adapter body, and the sliding mechanism may be caught by the object to be inspected and the optical adapter may come off. There is little nature.

Moreover, the optical adapter can be removed by hooking it with a sharp tool or the like to move the rotation restricting pin 68 so that the optical adapter can be easily removed. Description of other effects similar to those of the first embodiment will be omitted.

In FIG. 8, reference numeral 85 indicates the objective optical system 62.
Is the diaphragm mechanism.

12 to 14 show details of an example of the structure of the diaphragm mechanism. 12 is a sectional view of the tip of the insertion portion of the endoscope having the variable diaphragm mechanism, FIG. 13 is an explanatory view of the diaphragm mechanism, and FIG. 14 is a sectional view of the diaphragm mechanism.

In the objective optical system 75 arranged at the tip 9 of the endoscope shown in FIG. 12, a double focus lens 76 in which the central portion of the plane-parallel plate is convex is provided on the tip side. ing. The double-focus lens 76 has a large first aperture.
The diaphragm 77 is adhered. Further, a second diaphragm 78 having a small diaphragm hole is provided so as to be in contact with the first diaphragm 77 and rotate about an fulcrum 79 shown in FIG. 13 by an actuator 80. A positioning portion 76 a of the second diaphragm 77 is provided on the double focus lens 76 so as to project therefrom. This is done by molding the double-focus lens 76 by molding glass or plastic, and the positioning portion 76
a and the double focus lens 76 are integrated.

In the above configuration, when the distance from the endoscope distal end portion 9 to the object to be observed is at a far point such as 40 mm to ∞, the actuator 80 is driven to drive the movements shown in FIGS. As shown in (a), the second diaphragm 78
Moves away from the objective optical system 62 in the direction of arrow E in FIG. 12, and the first diaphragm 77 having a large diaphragm hole appears.

In the double-focus lens 76 in this state, since the diaphragm hole is wide open, the central convex portion 76b is ignored, and the double-focus lens 76 functions as a substantially parallel plane plate. Since the depth of field of the objective optical system 62 at this time is set to, for example, 40 mm to ∞, a good focused image can be obtained in the far point observation. Further, since the diameter of the aperture is large and the FNO is small, it is possible to obtain sufficient brightness for far point observation.

Next, when the distance from the endoscope tip 9 to the object to be observed is near, for example, 5 mm to 60 mm, as shown in FIGS. 13 (b) and 14 (b). To
By driving the actuator 80, the second diaphragm 78 having a small diaphragm hole is inserted into the objective optical system 62. Then, the second diaphragm 78 hits the positioning portion 76a formed integrally with the double focus lens 76,
Positioned. The light flux passes only through the convex portion 76b at the center of the double focus lens 76. That is, the double focus lens 76 functions as a convex lens. Since the depth of field of the objective optical system 62 at this time is set to, for example, 5 mm to 60 mm, it is possible to obtain a good focused image in the near point observation. Further, since the diameter of the aperture hole is small and the FNO is large, the light amount does not exceed in the near point observation.

As described above, by combining the double focus lens 76 and the variable aperture mechanism, it is possible to obtain two kinds of depth of field and brightness suitable for far point observation and near point observation. it can.

However, at the time of near point observation, that is, when the second diaphragm 78 having a small diaphragm hole is inserted into the objective optical system 62,
If the convex portion 76b at the center of the double focus lens 76 and the aperture hole do not exactly coincide with each other, the resolving power will be reduced or the observation depth range will be shifted to the near point side.

Therefore, in this embodiment, the positioning member 76a in which the second diaphragm 78 is provided integrally with the double focus lens 76 is provided.
It is positioned by abutting against. With such a structure, as compared with the case where the diaphragm positioning mechanism is provided separately from the lens, the diaphragm hole and the double focus lens 7 are provided.
6 The central convex portion 76b can be accurately aligned.

FIG. 15 is a block diagram of the diaphragm mechanism. In this diaphragm mechanism, a pin-shaped positioning member 76b is molded integrally with the double focus lens 76. Other configurations, operations, and effects are similar to those of the diaphragm mechanism shown in FIG.

Although the positioning member is provided in the double focus lens 76 shown in FIGS. 13 and 15, the positioning member may be integrated with the plane-parallel plate, the convex lens, the concave lens, etc. located in the vicinity of the diaphragm of the brightness. Good.

[0093]

According to the present invention, the first engaging portion provided at the distal end portion of the endoscope insertion portion is engaged with the movement restricting means, and the second engaging portion provided at the distal end portion. The rotation restricting means is biased by the biasing means so that the rotation restricting means is held in the engaged state. In this way, in this embodiment, the release of the engagement between the movement restricting means and the first engaging portion is restricted, and the optical adapter is locked in a state where the optical adapter does not easily drop from the distal end portion of the endoscope. You can keep the state.

Further, in this embodiment, the regulation is released by the force against the urging force of the urging means, the engagement between the movement regulating means and the first engaging portion is released, and the tip end portion is released. The optical adapter can be removed from the.

That is, in this embodiment, it is possible to securely and easily attach / detach the distal end portion of the endoscope and the optical adapter, and to ensure safety so as to prevent the detachment at the time of attachment, and to insert the endoscope. There is an effect that it is possible to reduce the outer diameter of the part.

[Brief description of drawings]

1 to 3 relate to a first embodiment of the present invention,
FIG. 1 is a cross-sectional view of the tip of the endoscope with an optical adapter attached.

FIG. 2 is an overall configuration diagram of an endoscope system.

FIG. 3 is a perspective view in which an optical adapter and a distal end portion of the endoscope are seen through.

4 and 5 relate to a second embodiment of the present invention, and FIG. 4 is a cross-sectional view of the distal end of the endoscope with an optical adapter attached.

FIG. 5 is a cross-sectional view for explaining removal of the optical adapter.

6 and 7 relate to a third embodiment of the present invention, and FIG. 6 is a cross-sectional view of the distal end of the endoscope with an optical adapter attached.

FIG. 7 is a cross-sectional view for explaining removal of the optical adapter.

8 to 11 relate to a fourth embodiment, and FIG. 8 is a cross-sectional view of a state in which an optical adapter is attached to the distal end portion of the endoscope.

9 (a) is a sectional view taken along the line AA of FIG. Figure 9
8B is a sectional view taken along the line BB in FIG.

10 is a view on arrow D in FIG. 8;

FIG. 11 is another configuration diagram of the captive wire.

FIG. 12 is a sectional view of a distal end of an insertion portion of an endoscope having a variable diaphragm mechanism.

FIG. 13 is an explanatory diagram of a diaphragm mechanism.

FIG. 14 is a sectional view of a diaphragm mechanism.

FIG. 15 is an explanatory diagram of a diaphragm mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Endoscope 9 ... End part of endoscope 22 ... L-shaped groove 23 ... Recess 31 ... Optical adapter 32 ... Adapter body 32c ... Mounting hole 33 ... Lever 36a ... Locking hole 37 ... Cap 38 ... Press spring 39 … Fixed pin 40… Rotation restriction pin

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[Procedure amendment]

[Submission date] January 19, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction content]

As shown in FIG . 2 , the endoscope system 1 includes
It is composed of a fiber type endoscope 2 and a light source device 3 which supplies illumination light to an observation target through the endoscope 2.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0032

[Correction method] Change

[Correction content]

The adapter body 32 has a fitting hole 32a formed at the rear end thereof for fitting with the tip 9, and an observation / illumination window 32b is formed from the side surface to the center of the fitting hole 32a.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction content]

The observation / illumination window 32b partially communicates with the fitting hole 32a, while the bottom portion is formed obliquely with respect to the axial direction. A mirror 34 is attached to the bottom.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0039

[Correction method] Change

[Correction content]

The rotation restricting pin 40 has the mounting hole 32.
In the state that the flange is inserted into
c is contacted with a step portion formed midway on the rear end side,
Is regulated so as not to move axially backward. Then, the rotation restricting pin 40 is pressed in the axial direction, the tip is adapted to fit projects, this concave <br/> portion 23 in the recess 23 side by the pressing spring 38.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction content]

Further, the lever portion 33 is formed with a recess 36b on the outer peripheral surface for hooking a finger to move the lever portion 33 itself forward and backward. That is, by hooking a finger or the like on the recess 36b and applying a force against the biasing force of the pressing spring 38, the rotation restricting pin 40 and the recess
It is configured to release the engagement with 23 .

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0042

[Correction method] Change

[Correction content]

An explanation of the attachment / detachment mechanism will be given with reference to FIGS. 3 (a) and 3 (b).
This will be described with reference to. The fixing pin 39 of the adapter body 32 is engaged with the locking hole 36a, and is assembled so that the lever 33 does not rotate about the pin 40 as a central axis. The rotation restricting pin 40 of the lever portion 33 is held slidably in the axial direction with respect to the adapter body portion 32, and is attached to the attachment hole 32c of the adapter body portion 32 by the pressing spring 38. It is pushed axially rearward. Therefore, the tip of the pin 40 moves rearward from the mounting hole 32c of the adapter body 32.
Overhangs . Further, even if the rotation restricting pin 40 moves axially forward against the pressing spring 38, the locking hole 36
The fixing pin 39 is formed to a length that does not deviate from a.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0048

[Correction method] Change

[Correction content]

On the other hand, the concave portion 36b of the head 36 is pulled with a finger in the Z direction shown in FIG. 3 (b), and the optical adapter 31 is rotated in the opposite direction to the assembling, that is, counterclockwise. In this way, by removing the fitting between the rotation restriction pin 40 and the recess 23 , the rotation restriction of the optical adapter 31 can be released. Then, in this state, the optical adapter 31 can be removed along the L-shaped groove 22.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0055

[Correction method] Change

[Correction content]

The rotation restricting pin 46 has a rear end connected to a pressing spring 48 as an urging means, and the spring 48 is connected to the rear end surface of the cap 49.
Therefore, the rotation restricting pin 46 is biased axially rearward by the pressing spring 48 so as to project from the mounting hole 45a .

[Procedure Amendment 9]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

Claims (1)

[Claims] 1. An optical adapter for an endoscope, which is detachably provided at a distal end portion of an endoscope insertion portion, which engages with a first engaging portion provided at the distal end portion by rotating in a circumferential direction. And a movement restricting member that restricts movement in the axial direction, and is slidable in the axial direction, and the distal end portion has the first engaging portion and the movement restricting member in an engaged state. A rotation restricting member that restricts rotation in the circumferential direction by engaging and engaging with the second engaging portion, and urging the rotation restricting member toward the second engaging portion. The optical adapter for an endoscope, comprising: a biasing unit that holds the state in which the circumferential rotation is restricted.