JP2008033098A - Optical adaptor and endoscope apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical adaptor that can be attached to a lens barrel part without limiting the installation and size of components in the lens barrel part and without making the diameter of the lens barrel part large, and to provide an endoscope apparatus equipped with the optical adaptor. <P>SOLUTION: The optical adaptor is freely detachably attached to the lens barrel part provided at the leading end part of an optical system for an endoscope apparatus, and the optical adaptor includes: an adaptor main body 9 into which the lens barrel part 3 is inserted; a fixing cylinder 15 into which the adaptor main body 9 is inserted, and which is displaceable back and forth relatively to the adaptor main body 9; and a projecting part 23 provided in the adaptor main body 9 and opposed to a step part 12b formed on the trailing end side of the lens barrel part 3. When the fixing cylinder 15 displaces forward, the displacement of the projecting part 23 from the position where the projecting part 23 opposed to the step part 12b formed on the trailing end side of the lens barrel part 3 to the outside is prevented by the fixing cylinder 15. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical adapter and an endoscope apparatus including the optical adapter.

  In order to observe the inside of a mechanical device such as an engine, a narrow space such as a human body esophagus, a body cavity such as a trachea, etc., a lens barrel portion including a photographing lens and an image sensor is inserted into the space, There is an endoscope apparatus that can display an image captured by the lens barrel on a monitor.

  In such an endoscope apparatus, an optical adapter may be attached to the lens barrel portion in order to change the focal length and the photographing direction of the photographing lens. As a configuration of this optical adapter, in a state where the locking claw provided in the optical adapter is locked in the groove formed in the outer tube of the lens barrel portion, by pressing the locking claw to the groove side by the ring tube, The structure which fixes an optical adapter to a lens-barrel part is disclosed by patent document 1, for example.

Japanese Patent Laying-Open No. 2005-270392 (see FIG. 1 etc.)

  However, in the configuration in which the groove portion is formed in the outer tube, a portion corresponding to the groove portion of the outer tube protrudes to the inner peripheral side, and the arrangement and size of components such as a lens disposed in the lens barrel portion are limited. There is a problem that.

  In addition, when the thickness of the outer tube is increased so that the portion corresponding to the groove portion of the outer tube does not protrude to the inner peripheral side, the outer diameter of the outer tube increases, and the larger diameter of the lens barrel portion There is a problem that it becomes a hindrance when inserting into a narrow space.

  Therefore, the present invention was made based on the circumstances as described above, without restricting the arrangement and size of the components inside the lens barrel, or without causing an increase in the diameter of the lens barrel, It is an object of the present invention to provide an optical adapter that can be attached to a lens barrel and an endoscope apparatus that includes the optical adapter.

  In order to solve the above-described problems, the present invention provides an optical adapter that is detachably attached to a lens barrel portion provided at a distal end portion of an endoscope apparatus, and an adapter main body into which the lens barrel portion is inserted, and the adapter main body is inserted. And a fixed cylinder that is displaceable in the front-rear direction relative to the adapter body, and a protrusion that is provided on the adapter body and faces a step on the rear end side of the lens barrel, When the fixed cylinder is displaced forward, the fixed cylinder is prevented from being displaced outward from the position facing the step on the rear end side of the lens barrel.

  In such a configuration, the optical adapter is dropped from the lens barrel without restricting the arrangement and size of the components inside the lens barrel and without increasing the diameter of the lens barrel. Can be prevented.

  In order to solve the above-described problems, the present invention provides an optical adapter that is detachably attached to a lens barrel portion provided at a distal end portion of an endoscope apparatus, and an adapter main body into which the lens barrel portion is inserted, and the adapter main body is inserted. And a fixed cylinder that is movable in the front-rear direction relative to the adapter body, a plate body that extends rearward from the adapter body, an inner surface of the fixed cylinder, and an outer surface of the plate body. The abutting portions that are in contact with each other, and are provided on the plate body, and in a state in which the lens barrel portion is inserted to a predetermined position of the adapter body, are located on the rear side of the step portion on the rear end side of the lens barrel portion, and on the inner side. It is assumed that at least one of the contact portions is an inclined surface that is inclined from the outside to the inside from the front to the rear.

  In such a configuration, the optical adapter is dropped from the lens barrel without restricting the arrangement and size of the components inside the lens barrel and without increasing the diameter of the lens barrel. Can be prevented. Furthermore, at least one of the abutting portions between the inner surface of the fixed cylinder and the outer surface of the plate body is configured by an inclined surface that is inclined from the outer side to the inner side from the front side to the rear side. Thus, a force that presses the plate against the lens barrel can be applied. Therefore, the optical adapter is fixed to the lens barrel part by pressing the plate body against the lens barrel part. Since the optical adapter is fixed to the lens barrel by the force with which the plate is pressed against the lens barrel by the contact portion, the arrangement and size of the components inside the lens barrel are limited, and the mirror The tube can be mounted on the lens barrel without causing an increase in diameter of the tube.

  In another invention, in addition to the above-described invention, the front surface of the protrusion is formed as an inclined surface that inclines from the outside toward the inside from the front to the rear, and the rear surface is from the front. It shall be formed in the inclined surface which inclines from the inner side to the outer side toward the back.

  In such a configuration, when the lens barrel is inserted into the adapter body, the inclined surface on the rear side of the protruding portion serves as a guide, and the lens barrel can be smoothly inserted into the adapter body. In addition, when the lens barrel is extracted from the adapter main body, the inclined surface on the front side of the protrusion serves as a guide, and the lens barrel can be smoothly extracted from the adapter main body.

  In addition to the above-described invention, in another invention, the inner surface of the adapter body is provided with a positioning projection that protrudes inward and abuts against the front end portion of the lens barrel portion. It is assumed that a gap is provided between the rear end portion of the lens barrel portion and the protruding portion in a state where the projection is in contact with the positioning projection.

  In the case of such a configuration, even if the length of the lens barrel portion varies, there is no gap between the lens barrel portion and the protruding portion because the interval is provided.

  In another invention, in addition to the above-described invention, the contact portions are in surface contact with each other.

  When configured in this way, the pressing force from the abutting portion on the fixed cylinder side to the abutting portion on the adapter main body side can be reliably applied.

  In addition to the above-mentioned invention, in another invention, the shape along the circumferential direction of the lens barrel portion of the plate body is a shape along the circumferential shape of the outer peripheral surface of the lens barrel portion.

  When configured in this way, the plate body has a shape that follows the shape of the outer peripheral surface of the lens barrel portion, the contact area between the plate body and the lens barrel portion increases, and the force with which the plate body presses the lens barrel portion is ensured. Act on.

  In addition to the above-described invention, in another invention, the inner surface of the plate body and the inner peripheral surface of the adapter main body other than the plate body are flush with each other.

  When configured in this manner, the pressing force can be applied to the lens barrel portion over a wide area, so that the optical adapter can be reliably fixed to the lens barrel portion.

  According to another invention, in addition to the above-described invention, a protruding portion is provided on the outer surface of the plate body, and the fixed cylinder has an engaging portion that engages with the protruding portion on the front side of the protruding portion. Is assumed to be formed.

  In such a configuration, since the engaging portion formed on the fixed cylinder side is engaged with the front side surface of the protruding portion, it is possible to prevent the adapter main body from falling out of the fixed cylinder.

  According to another invention, in addition to the above-described invention, the adapter main body and the fixed cylinder have a screw coupling portion that is screw-coupled to each other. It moves to the front and rear direction.

  In such a configuration, the fixed cylinder can be easily and reliably moved.

  In order to solve the above-described problems, the present invention includes the above-described optical adapter in an endoscope apparatus.

  In such a configuration, the optical adapter is dropped from the lens barrel without restricting the arrangement and size of the components inside the lens barrel and without increasing the diameter of the lens barrel. Can be prevented.

  According to the present invention, the optical adapter can be mounted on the lens barrel without restricting the arrangement and size of the components inside the lens barrel and without increasing the diameter of the lens barrel. .

  Hereinafter, an optical adapter and an endoscope apparatus according to embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
First, an optical adapter and an endoscope apparatus according to a first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a diagram showing a configuration of an endoscope apparatus 1 to which an optical adapter according to the present embodiment and a second embodiment described later is mounted. As shown in FIG. 1, the endoscope apparatus 1 includes a control device 2, a lens barrel portion 3, and a connection cable 4. This endoscope apparatus 1 can be used as an endoscope apparatus for photographing the inside of a mechanical device such as an engine, and can also be used for photographing a body cavity such as a human esophagus and trachea.

  The control device 2 is provided with a monitor 2a on which an image taken in the lens barrel unit 3 is displayed, and an operation button 2b for controlling the endoscope device 1. The monitor 2a is composed of, for example, a liquid crystal display element. The operator operates the operation button 2b to start various control operations such as control operation of the endoscope device 1, for example, turning on / off the power of the endoscope device 1, start of photographing, and adjustment of image quality. It can be carried out.

  The lens barrel 3 includes a photographing lens 5 (see FIGS. 4 and 5), an image sensor 6 (see FIGS. 4 and 5) such as a CCD or a CMOS, and an illumination LED 7 (see FIGS. 4 and 5). And a camera unit configured to image an image formed by the photographic lens 5 with the image sensor 6.

  The connection cable 4 includes a flexible tube 4c in which a so-called spiral tube 4a formed by winding a thin metal plate in a spiral shape is covered with a resin tube 4b, and a signal line 4d inserted into the flexible tube 4c. (See FIG. 4 and FIG. 5). The flexible tube 4c can change the line shape by a human hand, and has rigidity enough to support the lens barrel 3 with respect to the control device 2 while maintaining the changed shape. Therefore, by matching the line shape of the connection cable 4 to the shape of the space or gap into which the lens barrel portion 3 is inserted, the lens barrel portion 3 can easily enter the space or the gap.

  The lens barrel portion 3 and the control device 2 are electrically connected via a signal line 4d, and an image signal photographed by the lens barrel portion 3 is sent to the control device 2, and the control device 2 receives an image sensor. 6 and the electric signal which drive-controls LED7 and an electric signal are sent.

  Next, the configuration of the optical adapter 8 attached to the endoscope apparatus 1 will be described with reference to FIGS. 2 to 6. Note that the optical adapter 8 is attached to the endoscope apparatus 1, whereby the endoscope apparatus according to the first embodiment is obtained.

  FIG. 2 shows a side view of the optical adapter 8 attached to the lens barrel 3 of the endoscope apparatus 1. FIG. 3 is a view showing a configuration of the adapter main body 9 of the optical adapter 8, and FIG. 3A is a side view of the adapter main body 9. FIG. 3B is a rear view of the adapter body 9 as viewed from the rear. FIG. 4 is a side sectional view of the optical adapter 8 and the lens barrel 3 in a state where the lens barrel 3 is inserted into the optical adapter 8. The state shown in FIG. 4 is a state in which the lens barrel portion 3 is simply inserted into the optical adapter 8, and the optical adapter 8 is not fixed to the lens barrel portion 3. FIG. 5 is a side sectional view of the optical adapter 8 and the lens barrel unit 3 in a state where the optical adapter 8 in which the lens barrel unit 3 is inserted is fixed to the lens barrel unit 3. FIG. 6 is an enlarged view of a portion A in FIG.

  Here, the configuration of the lens barrel 3 will be described with reference to FIG. 4 and others. As described above, the lens barrel unit 3 includes the photographing lens 5, the image sensor 6, and the LED 7.

  In the following description, the direction from the image sensor 6 toward the photographing lens 5 is the front (front side), the opposite direction is the rear (rear side), and the direction in which the photographing lens 5 is disposed with respect to the LED 7 is upward ( The upper side) and the opposite direction will be described as the lower side (lower side). Further, the description will be made with the right hand side as the right side (right side) and the left hand side as the left side (left side) as viewed from the front from the rear.

  A subject image captured by the photographing lens 5 is formed on the imaging surface of the imaging element 6. The image formed on the image sensor 6 is subjected to image processing and the like by the image signal processing circuit unit on the circuit board 10 and then sent to the control device 2 side through the signal line 4d.

  The LED 7 disposed below the photographing lens 5 is provided for illumination for illuminating a photographing subject. With this LED 7, it is possible to take a picture while illuminating the inside of a dark mechanical device. The LED 7 is lit by receiving power from the control device 2 side via the signal line 4d.

  The photographic lens 5, the imaging device 6, and the circuit board 10 are held by a cylindrical optical system holding cylinder 11, and the optical system holding cylinder 11 and the LED 7 are held by a cylindrical outer cylinder 12. The exterior cylinder 12 is formed of a rigid hard member, for example, in order to protect the internal optical system holding cylinder 11, the LED 7, and the like from an external impact or the like. Specifically, it is made of, for example, a metal such as stainless steel or aluminum, or a resin material such as polycarbonate or ABS having high hardness. Further, the outer peripheral portion of the outer cylinder 12 has a smooth cylindrical surface with no irregularities so that it is not caught by an internal structure or the like when inserted into a narrow interior.

  In the following description, the direction toward the central axis M along the front-rear direction of the exterior cylinder 12 is defined as the inside, and the direction away from the central axis M is defined as the outside.

  A substantially circular cover plate 13 is attached to the inside of the front end portion of the outer cylinder 12. The cover plate 13 is formed with a hole 13a into which the optical system holding cylinder 11 is fitted, and the optical system holding cylinder 11 is fitted into the hole 13a. The optical system holding cylinder 11 is held with respect to the exterior cylinder 12 via the cover plate 13. Further, a transparent plate 13b is fitted under the hole 13a of the cover plate 13, and the illumination light of the LED 7 can pass through the transparent plate 13b to illuminate the subject side. The joint between the hole 13a and the optical system holding cylinder 11, the joint between the cover plate 13 and the exterior cylinder 12, and the joint between the transparent plate 13b and the cover plate 13 are in a watertight state. .

  A connecting cable 4 having a circular cross section is inserted into the opening 12 a at the rear end of the outer tube 12, and is a cylindrical shape that is fitted between the inner peripheral surface of the outer tube 12 and the outer peripheral surface of the tip of the connecting cable 4. The sealing ring 14 secures the connection cable 4 and the outer cylinder 12 and also ensures water tightness.

  Since the connection cable 4 is inserted into the outer tube 12, the outer tube 12 protrudes outward from the outer periphery of the connection cable 4, and the end surface of the rear end portion 12 b is a step on the rear end side of the lens barrel portion 3. It is formed.

  Next, the configuration of the optical adapter 8 will be described.

  The optical adapter 8 includes an adapter main body 9 and a fastening cylinder 15 as a fixed cylinder. The adapter body 9 and the fastening cylinder 15 are made of, for example, a metal such as stainless steel or aluminum, or a resin material such as polycarbonate or ABS having high hardness.

  The adapter main body 9 has a cylindrical body as a whole, and includes a mirror support holding part 16, a lens barrel holding part 17, and a lens barrel fixing part 18 in order from the front. These are integrally molded and formed as an adapter body 9. In addition, the mirror support body holding part 16 says from the front-end | tip of the adapter main body 9 to the positioning projection 20 mentioned later, and the lens-barrel holding part 17 says from the positioning projection 20 to the junction part 22a mentioned later. And the lens-barrel fixing | fixed part 18 says the back side from the junction part 22a.

  A mirror support 19 is held inside the mirror support holding part 16. The mirror support holder 16 is formed with an opening 16a that opens from the left and right sides to the top.

  The mirror support 19 has a shape obtained by cutting one end of a cylindrical body with a slope. That is, the mirror support 19 has a substantially cylindrical shape, but the rear end side is formed as an inclined surface 19a. The mirror support 19 is made of the same material as the adapter main body 9.

  The outer peripheral diameter of the cylindrical portion 19 b of the mirror support 19 is set so as to fit just inside the mirror support holding portion 16 in accordance with the inner peripheral diameter of the mirror support holding portion 16. The inclined surface 19a is inclined at an angle of 45 degrees from the upper side to the lower side toward the rear. The inclined surface 19a is finished as a mirror surface by polishing and is formed as a mirror surface 19c. The mirror surface 19c may be formed on the inclined surface 19a by performing aluminum vapor deposition or the like.

  The mirror support 19 is inserted into the mirror support holding part 16 from the opening 9a on the distal end side of the adapter body 9, and the mirror surface 19c (inclined surface 19a) is directed upward, that is, from the opening 16a to the mirror. It is held in the mirror support holding part 16 with the surface 19c facing. The rear end portion of the mirror support 19 is brought into contact with a positioning protrusion 20 formed on the lower side of the inner peripheral surface of the adapter main body 9, whereby the mirror support 19 is moved in the front-rear direction in the mirror support holding portion 16. Positioning is performed. The optical adapter 8 including the mirror support 19 functions as an optical adapter that changes the shooting direction of the lens barrel 3 by the mirror surface 19c.

  The lens barrel part 3 is held inside the lens barrel holding part 17. The inner diameter of the lens barrel holding portion 17 is substantially the same as the outer diameter of the lens barrel portion 3 (exterior cylinder 12), and the lens barrel portion 3 is as loose as possible in the vertical and horizontal directions with respect to the lens barrel holding portion 17. The diameter of both is set so that there is no. The lens barrel portion 3 is inserted into the lens barrel holding portion 17 from the rear of the lens barrel fixing portion 18, and the front end portion 12 c of the outer tube 12 is brought into contact with the positioning projection 20 to perform positioning in the front-rear direction. Is called.

  With the front end portion 12c of the outer tube 12 in contact with the positioning projection 20, more than half of the total length in the front-rear direction of the lens barrel portion 3, for example, about 3/5 is inserted into the lens barrel holding portion 17. As described above, the length of the lens barrel holding portion 17 and the arrangement position of the positioning projections 20 are set.

  The lens barrel part 3 may have a back and forth rattling by a slight gap with the inner peripheral surface of the lens barrel holding part 17. In such a case, the lens barrel portion 3 swings in a direction intersecting with the central axis M around the portion held by the lens barrel holding portion 17. Therefore, the amount of oscillation on the rear end side of the lens barrel portion 3 can be reduced when the length of the lens barrel portion 3 held by the lens barrel holding portion 17 is longer than when the length is shorter. That is, when more than half of the lens barrel part 3 is inserted and held in the lens barrel holding part 17, rattling of the lens barrel part 3 with respect to the adapter main body 9 can be effectively suppressed.

  On the outer peripheral surface on the rear side of the lens barrel holding portion 17, a male screw 21 that is screw-coupled to a tightening tube 15 described later is formed. A lens barrel fixing portion 18 is provided on the rear side of the lens barrel holding portion 17 where the male screw 21 is formed. The lens barrel fixing portion 18 is a plate 22, 22, 22, 22 provided in four directions, up, down, left, and right, and a protruding portion provided at the rear end of these plates 22 and protruding inward. And a protrusion 23. In addition, an inclined surface 24 that is inclined from the outside to the inside from the front to the rear is formed at the outer edge of the rear end portion of each plate 22. Each plate 22 has an arc shape in cross section on a plane orthogonal to the central axis M. As shown in FIG. 3B, the plate bodies 22 are provided symmetrically with respect to the central axis M in the vertical and horizontal directions. Further, the width of each plate 22 is set to be approximately 1/8 of the circumference of the inner peripheral surface of the lens barrel fixing portion 18.

  Furthermore, the thickness of each plate 22 is formed thinner than the thickness of the portion where the male screw 21 of the lens barrel holding portion 17 is formed on both the inside and outside. Accordingly, each plate 22 is elastically flexible in the inner and outer directions, and can be bent inward and outward with the joint portion 22a with the lens barrel holding portion 17 as the center. It has become.

  The protruding portion 23 is located behind the rear end portion 12b of the outer tube 12 in a state where the lens barrel portion 3 is inserted into the adapter body 9 and the front end portion 12c of the outer tube 12 is brought into contact with the positioning projection 20. The length of each plate 22 is set so as to be positioned.

  The front and back surfaces of the protrusion 23 are formed as inclined surfaces 23a and 23b, respectively. The front inclined surface 23a is a slope inclined from the outside to the inside from the front to the rear. The rear inclined surface 23b is a slope inclined from the inside to the outside from the front to the rear.

  The fastening cylinder 15 has a cylindrical body as a whole, and an internal thread 25 is formed on the inner peripheral surface thereof. The internal thread 25 is coupled to the external thread 21 formed on the outer peripheral surface of the lens barrel fixing portion 18 described above. The tightening cylinder 15 advances and retreats in the front-rear direction according to the lead of the male screw 21 and the female screw 25 by rotating so as to change the amount of screw coupling between the male screw 21 and the female screw 25. Further, the rear cylindrical portion of the female screw 25 is configured as a plate body insertion portion 26 into which each plate body 22 of the adapter main body 9 is inserted. The inner peripheral diameter of the plate body insertion portion 26 is set so that the outer surface of each plate body 22 to be inserted comes into contact. The curvature in the circumferential direction of the central axis M of the outer surface of each plate 22 and the curvature of the inner peripheral surface of the plate insertion portion 26 are the same, and the entire outer surface of each plate 22 is within the plate insertion portion 26. It touches the peripheral surface.

  As shown in FIG. 2, knurled grooves 9b and 15a are formed on the outer peripheral surfaces of the adapter main body 9 and the fastening cylinder 15, respectively. Therefore, even if oil is attached to the clamping tube 15 and the adapter main body 9 and the finger to be picked, it can be picked without slipping, and the tightening tube 15 can be reliably rotated with respect to the adapter main body 9.

  A protruding portion 27 that protrudes inward is formed at the rear end portion of the plate body insertion portion 26, that is, the opening portion 15 b that is the rear end portion of the fastening cylinder 15. The protruding portion 27 is formed on the entire inner periphery of the opening 15b. The front and back surfaces of the protrusion 27 are formed as inclined surfaces 27a and 27b, respectively. The front inclined surface 27a is an inclined surface that is inclined from the outside to the inside from the front to the rear. The rear inclined surface 27b is a slope inclined from the inside to the outside from the front to the rear. The inclined surface 24 and the inclined surface 27a described above are formed so as to overlap each other in the front-rear direction.

  As shown in FIGS. 2, 4, and 5, the optical adapter 8 inserts the lens barrel fixing portion 18 of the adapter main body 9 into the tightening tube 15, and the male screw 21 and the tightening tube 15 on the adapter main body 9 side. The side female screw 25 is used in a state where it is screwed.

  Prior to mounting the optical adapter 8 on the lens barrel 3, the inclined surface 27 a of the projecting portion 27 of the fastening tube 15 does not contact or slightly contacts the inclined surface 24 of the rear end of each plate 22. The amount of screw coupling between the male screw 21 of the adapter main body 9 and the fastening cylinder 15 female screw 25 is adjusted so as to be in a state. Then, the lens barrel 3 is inserted into the adapter main body 9 from the opening 15b at the rear of the tightening tube 15, and the front end 12c of the outer tube 12 is brought into contact with the positioning projection 20 as shown in FIG. Let

  As described above, each plate body 22 is thinner than the lens barrel holding portion 17, and therefore, with the lens barrel portion 3 inserted in the lens barrel holding portion 17, A gap D1 is formed between the side surface and the exterior cylinder 12 of the lens barrel 3.

  The amount of screw coupling between the male screw 21 of the adapter body 9 and the female screw 25 of the fastening cylinder 15 is such that the inclined surface 27a of the projecting portion 27 does not abut against the inclined surface 24 of the rear end portion of each plate 22 or When lightly abutting, the distance between the apexes of the protrusions 23 facing each other in the upper, lower, left, and right directions of each plate 22 (diameter of the circle in contact with each apex) L1 is slightly larger than the outer peripheral diameter of the exterior cylinder 12. Further, the protruding amount of the protruding portion 23 is set.

  Therefore, in a state where the male screw 21 of the adapter main body 9 and the female screw 25 of the fastening cylinder 15 are screw-coupled to the extent that the inclined surface 27a of the protruding portion 27 does not contact the inclined surface 24 of each plate body 22, The lens barrel portion 3 can be inserted into the lens barrel holding portion 17 of the adapter main body 9 through the space between the projecting portions 23 facing each other in the vertical and horizontal directions. The inner diameter R1 at the apex of the protrusion 27 is also set larger than the outer diameter of the outer cylinder 12 so that the outer cylinder 12 can pass through.

  The rear surface inside the protrusion 23 is formed as an inclined surface 23b. Therefore, when the lens barrel 3 is inserted into the adapter main body 9, the front end 12 c is guided by the inclined surface 23 b even if the front end 12 c of the outer cylinder 12 hits the protruding portion 23. 9 can be inserted smoothly.

  The inner diameter R <b> 1 at the apex portion of the projecting portion 27 is such that the amount of screw coupling between the male screw 21 of the adapter body 9 and the female screw 25 of the fastening cylinder 15 is such that the inclined surface 27 a of the projecting portion 27 is the rear end portion of each plate 22. The distance between the outer surfaces of the plate bodies 22 facing each other in the vertical and left and right directions (the diameter of a circle in contact with the outer surface of each plate body) L2 Is set smaller than. Therefore, when the amount of coupling between the male screw 21 and the female screw 25 is increased and the fastening cylinder 15 is displaced forward with respect to the adapter main body 9, the inclined surface 27 a comes into contact with the inclined surface 24 of each plate 22. It is possible. That is, the inclined surface 24 and the inclined surface 27a are formed to have surfaces that overlap each other in the front-rear direction.

  As described above, the lens barrel 3 is inserted into the adapter main body 9 until the front end 12c of the outer cylinder 12 contacts the positioning projection 20, and then the clamping cylinder 15 is rotated to remove the clamping cylinder 15. Tighten to the adapter body 9. That is, the tightening tube 15 is rotated in a direction in which the amount of screw coupling between the male screw 21 and the female screw 25 is increased, and the tightening tube 15 is displaced forward relative to the adapter main body 9, and the state shown in FIG. And

  That is, when the tightening tube 15 is tightened with respect to the adapter main body 9, and the tightening tube 15 is displaced forward with respect to the adapter main body 9, the inclined surface 27 a of the protruding portion 27 is moved to the rear of each plate 22. It contacts the inclined surface 24 at the end. As the tightening cylinder 15 is displaced forward, the inclined surface 24 gradually receives a pressing force directed inward by the inclined surface 27a. When a pressing force directed inwardly acts on the inclined surface 24 of each plate 22, a gap D <b> 1 is formed between each plate 22 and the exterior cylinder 12, so according to the strength of the pressing force, Each plate 22 bends inward. That is, as the fastening cylinder 15 is tightened with respect to the adapter main body 9, the interval between the opposing plate bodies 22 becomes narrower from the front to the rear, and finally the rear side of the inner surface of each plate body 22. The end side comes into contact with the outer peripheral surface of the rear end portion 12 b of the exterior cylinder 12.

  As shown in FIG. 5, in a state where the inner surface of each plate 22 is in contact with the outer peripheral surface of the rear end portion 12 b of the outer tube 12, the tightening tube 15 is further tightened against the adapter body 9. As a result, the outer peripheral surface of the rear end portion 12 b of the outer cylinder 12 is sandwiched between the inner side surfaces of the opposing plate bodies 22, and the adapter main body 9 is fixed to the lens barrel portion 3.

  In this manner, the optical adapter 8 is fixed to the lens barrel portion 3 by sandwiching the outer tube 12 by the inner surface of each plate 22. That is, since it is not necessary to provide a configuration for fixing the optical adapter 8 on the exterior tube 12 side, there is a limit to the arrangement and size of components such as the lens 5 and the image sensor 6 inside the lens barrel portion 3. The optical adapter 8 can be attached to the lens barrel 3 without giving or inviting an increase in the diameter of the lens barrel 3.

  The rear end of each plate 22 is at least inside the gap D1 when the optical adapter 8 is fixedly attached to the lens barrel 3 and before the optical adapter 8 is fixed to the lens barrel 3. Displace. Therefore, the interval L1 between the protruding portions 23 of the opposing plate bodies 22 is smaller than the outer peripheral diameter of the exterior cylinder 12. That is, as shown in FIG. 5, the protruding portion 23 of each plate 22 is disposed on the rear side of the end face of the rear end portion 12 b of the exterior cylinder 12. Moreover, since the inclined surface 24 receives the pressing force directed inward by the inclined surface 27a of the protruding portion 27, the protruding portion 23 is prevented from being displaced outward.

  By the way, the screw connection between the fastening cylinder 15 and the adapter main body 9 is loosened, and the force that each plate 22 sandwiches the exterior cylinder 12 is weakened, and the optical adapter 8 moves in the front-rear direction with respect to the exterior cylinder 12. It may happen that it will be in a state where it ends up. Even in such a case, the projecting portion 23 is disposed on the rear side of the rear end portion of the exterior tube 12 in a state in which the outward displacement is prevented, so that the projecting portion 23 is provided in the exterior tube. 12, the optical adapter 8 can be prevented from falling off the lens barrel 3. That is, the optical adapter 8 is prevented from falling off the lens barrel 3 even when the screw connection between the fastening cylinder 15 and the adapter body 9 is loosened while observing the inside of the mechanical device or the like. can do.

  Thus, since the protrusion 23 is disposed on the rear side of the rear end portion of the exterior cylinder 12, the protrusion 23 is engaged with the rear end 12 b of the exterior cylinder 12. It is not necessary to provide a configuration for preventing the optical adapter 8 from dropping off on the side. Therefore, there is no limitation on the arrangement and size of components such as the lens 5 and the imaging element 6 inside the lens barrel portion 3, and the diameter of the lens barrel portion 3 is not increased. It is possible to prevent the optical adapter 8 from falling off.

  Further, in a state where the force for sandwiching the outer cylinder 12 of each plate 22 is weakened and the optical adapter 8 moves back and forth with respect to the outer cylinder 12, the positioning between the positioning projection 20 and the protrusion 23 is performed. The lens barrel 3 is rattling. Therefore, it is possible to know that the screw connection between the tightening cylinder 15 and the adapter main body 9 is loose due to the rattling.

  As shown in FIG. 5, in a state where the optical adapter 8 is fixedly attached to the lens barrel portion 3, there is a gap between the front end portion of the inclined surface 23 a of the projecting portion 23 and the rear end portion of the exterior tube 12. For example, the position where the protrusion 23 is formed is set so that S1 is formed with an interval of 1 mm, for example. Thus, by providing the gap S1 between the projecting portion 23 and the rear end portion of the exterior cylinder 12, even if there is some variation in the length of the exterior cylinder 12 in the front-rear direction, the exterior cylinder 12 The rear end portion 12b can be positioned in front of the protruding portion 23.

  The shape of the cross section in the plane orthogonal to the central axis M of each plate 22 is an arc shape. Therefore, the cross section of the protrusion 23 in a plane orthogonal to the central axis M is also arc-shaped, and the inclined surface 23 a is also an arc-shaped surface in the circumferential direction of the central axis M. Therefore, when the protrusion 23 is engaged with the rear end 12b of the exterior cylinder 12, the protrusion 23 is engaged along the arc of the rear end 12b of the exterior cylinder 12, and the engagement is It can be certain.

  The inclined surface 24 and the inclined surface 27a have the same inclination angle. Further, the outer surface of each plate 22 and the inner peripheral surface of the fastening cylinder 15 are curved surfaces having the same curvature that are in contact with each other. That is, the inclined surface 24 and the inclined surface 27a are curved surfaces having the same curvature around the central axis M. Therefore, the inclined surface 24 and the inclined surface 27a can be brought into surface contact with each other over a wide area, and the contact portion is not biased to a part, and the pressing force can be reliably applied to the inclined surface 24 from the inclined surface 27a. it can.

  In the present embodiment, the abutting portion is formed by the inclined surface 24 and the inclined surface 27a, but either one of the inclined surface 24 and the inclined surface 27a is not a inclined surface but a protruding portion. It is good also as a structure which contact | abuts the vertex part of a part to the other inclined surface.

  Since the cross-sectional shape of each plate 22 is arcuate, the inner surface of each plate 22 is along the outer peripheral surface of the exterior cylinder 12. For this reason, in the abutting portion between each plate body 22 and the exterior cylinder 12, a portion that contacts the direction along the circumferential direction of the central axis M increases, so that the force with which each plate body 22 presses the exterior cylinder 12 is ensured. Will act.

  Next, an operation for removing the optical adapter 8 attached and fixed to the lens barrel 3 as described above from the lens barrel 3 will be described.

  First, the tightening cylinder 15 is rotated to weaken the tightening of the screw connection with the adapter main body 9. Thereby, the fastening cylinder 15 is displaced rearward, and the inclined surface 27a is also displaced rearward. Therefore, the force that the inclined surface 27a pushes the inclined surface 24 of each plate 22 inward is weakened, and each plate 22 that has been pushed and bent inward by the gap D1 is restored to the outside by its own elastic restoring force, As shown in FIG. 4, it becomes a straight state. In this state, the inner surface of each plate body 22 eliminates the force for sandwiching the outer tube 12, and the protruding portion 23 of each plate body 22 is located from a position facing the end surface of the rear end portion 12 b of the outer tube 12. The outer cylinder 12 is retracted outside the outer peripheral surface.

  That is, as shown in FIG. 4, the interval between the apexes of the projecting portion 23 is L1, and the lens barrel portion 3 can be pulled out from the adapter body 9 backward. That is, the optical adapter 8 can be detached from the lens barrel portion 3.

  By the way, the surface on the inner side of the protrusion 23 is formed as an inclined surface 23a. Therefore, when the optical adapter 8 is extracted from the lens barrel 3, even if the rear end of the outer tube 12 hits the protruding portion 23, the rear end is guided by the inclined surface 23 a, so that it can be extracted smoothly.

(Second Embodiment)
Next, an optical adapter 28 according to a second embodiment of the present invention will be described with reference to FIGS. In addition, when this optical adapter 28 is attached to the endoscope apparatus 1, the endoscope apparatus according to the second embodiment is obtained.

  In the optical adapter 28, the configurations of the lens barrel fixing portion 29 and the fastening tube 30 are different from the configurations of the lens barrel fixing portion 18 and the fastening tube 15 of the optical adapter 8 according to the first embodiment. The front of the lens barrel fixing portion 29 has the same configuration as the lens barrel holding portion 17, the mirror support holding portion 16 and the mirror support 19 in the optical adapter 8 according to the first embodiment described above. 7, 8, and 9 mainly show the configurations of the lens barrel fixing portion 29 and the fastening tube 30, and the rear of the lens barrel holding portion 31, which corresponds to the lens barrel holding portion 17. A part of the side is shown in the drawing, and description and illustration of portions corresponding to the mirror support holding part 16 and the mirror support 19 are omitted. Further, the same components as those of the endoscope apparatus 1 and the optical adapter 8 according to the other first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 7 is a side sectional view of the optical adapter 28 in a state where the lens barrel 3 is inserted into the optical adapter 28. The state shown in FIG. 7 is a state in which the lens barrel 3 is simply inserted into the optical adapter 28, and the optical adapter 28 is not fixed to the lens barrel 3. FIG. 8 is a side sectional view of the optical adapter 28 in a state where the optical adapter 28 into which the lens barrel portion 3 is inserted is fixed to the lens barrel portion 3. FIG. 9 is a side sectional view of the optical adapter 28 during insertion of the lens barrel 3 into the optical adapter 28 or during removal of the optical adapter 28 from the lens barrel 3. FIG. 10 is an enlarged view of a portion B in FIG.

  The lens barrel fixing portion 29 is provided with plate bodies 32, 32, 32, 32 provided in four directions, up, down, left and right, and rear end portions of these plate bodies 32 in the same manner as the plate bodies 22 of the first embodiment. And a protrusion 33 that is a protrusion protruding inward and a protrusion 34 provided on the outer side of each plate 32. The lens barrel fixing portion 29 is configured to be integrally formed with the lens barrel holding portion 31 behind the lens barrel holding portion 31. A male screw 35 is formed on the outer peripheral surface of the lens barrel holding portion 31.

  Each plate 32 is provided symmetrically with respect to the central axis M in the vertical and horizontal directions. Further, the width of each plate 32 is set to be approximately 1/8 of the circumference of the inner peripheral surface of the lens barrel fixing portion 29. Further, each plate 32 is flush with the inner peripheral surface of the lens barrel holding portion 31 on the inner side, but on the outer side, the meat of the cylinder forming the lens barrel holding portion 31 is provided. It is formed thinner than the thickness. Accordingly, each plate 32 is elastically flexible in the inner and outer directions, and can be bent inward and outward around the joint portion 32a with the lens barrel holding portion 31. ing.

  The protrusion 33 is formed by combining the lens barrel 3 with a mirror support holding unit (not shown) (corresponding to the mirror support holding unit 16 in the first embodiment), the lens barrel fixing unit 29 and the lens barrel holding unit 31. Inserted into the adapter body 36 to be molded, the rear end 12b of the outer cylinder 12 is in a state where the front end 12c of the outer cylinder 12 is in contact with a positioning projection 20 (not shown) (see FIGS. 4 and 5). The length of each plate body 32 is set so as to be positioned rearward from the side.

  The front and rear surfaces of the protrusion 33 are formed as inclined surfaces 33a and 33b, respectively. The front inclined surface 33a is a slope inclined from the outside to the inside from the front to the rear. The rear inclined surface 33b is a slope inclined from the inside to the outside from the front to the rear.

  The shape of the cross section in the plane orthogonal to the central axis M of each plate 32 is an arc shape. Therefore, the cross section of the protrusion 33 in a plane orthogonal to the central axis M is also arcuate, and the inclined surfaces 33a and 33b are arcuate surfaces in the circumferential direction of the central axis M.

  Each protruding portion 34 is inserted from the rear end portion of the outer tube 12 in a state where the lens barrel portion 3 is inserted into the adapter main body 36 and the front end portion 12c of the outer tube 12 is in contact with the positioning projection 20 (not shown). It is arrange | positioned so that it may be located ahead. That is, it is disposed in front of each protrusion 33. Each protrusion 34 has a width in the front-rear direction, and has the same width as the width of each plate 32 in the circumferential direction around the central axis M. That is, each protrusion 34 protrudes in a trapezoidal shape as a whole, and the outer surface 34a of each protrusion 34 is a curved surface along the circumferential direction of the central axis M like each plate 32, and extends from the front to the rear. It is formed in the inclined surface which inclines toward the inside from the outside.

  The fastening cylinder 30 has a cylindrical body as a whole, and an internal thread 37 is formed on the inner peripheral surface thereof. The female thread 37 is coupled to the external thread 35 formed on the outer peripheral surface of the lens barrel holding portion 31 described above. The tightening cylinder 30 advances and retreats in the front-rear direction according to the lead of the male screw 35 and the female screw 37 by rotating so as to change the amount of screw coupling between the male screw 35 and the female screw 37. Further, the cylindrical portion on the rear side of the female screw 37 is configured as a plate body insertion portion 38 into which each plate body 32 of the adapter main body 36 is inserted.

  The protruding portion 34 can be fitted to the inner peripheral surface of the fastening tube 30 at a position facing the protruding portion 34 when the optical adapter 28 is not fixed to the lens barrel portion 3 (the state shown in FIG. 7). A concave portion 39 is formed. The recess 39 is formed over the entire circumference of the inner peripheral surface of the fastening cylinder 30.

  An inclined surface 40 is formed over the entire inner peripheral surface of the inner peripheral surface of the fastening cylinder 30 behind the recess 39. The inclined surface 40 is an inclined surface that is inclined inwardly from the outside toward the rear from the rear edge of the concave portion 39, and is an inclined surface having the same inclination as the outer surface 34 a of the protruding portion 34. The inclined surface 40 and the inclined surface 34a are formed so as to have overlapping surfaces in the front-rear direction. Therefore, as shown in FIG. 8, the outer side surface 34 a of the projecting portion 34 comes into contact with the inclined surface 40 in a state where the fastening cylinder 30 is tightened with respect to the adapter main body 36.

  As shown in FIGS. 7, 8, and 9, the optical adapter 28 inserts the lens barrel fixing portion 29 of the adapter main body 36 into the tightening tube 30, and the male screw 35 and the tightening tube 30 on the adapter main body 36 side. The side female screw 37 is used in a state where it is screwed.

  Prior to mounting the optical adapter 28 on the barrel 3, the male screw 35 of the adapter main body 36 and the female screw 30 of the clamping cylinder 30 are arranged so that the recess 39 of the clamping cylinder 30 and the protrusion 34 of each plate 32 face each other. The amount of binding with 37 is adjusted in advance. Then, the lens barrel 3 is inserted into the adapter main body 36 through the opening 30a behind the tightening tube 30, and the front end 12c of the outer tube 12 is brought into contact with the positioning projection 20 (not shown).

  Since the inner side surface of each plate 32 is flush with the inner peripheral surface of the lens barrel holding portion 31, the outer peripheral surface of the outer tube 12 inserted into the adapter main body 36 and the inner side surface of each plate 32. Will be in contact. Therefore, the protruding portion 33 that protrudes inward from the inner surface of each plate 32 protrudes to the rear side of the edge of the rear end portion of the exterior cylinder 12. That is, the distance between the apexes of the protrusions 33 of each plate 32 facing each other (the diameter of the circle in contact with each apex) L3 is smaller than the outer diameter of the outer cylinder 12. Therefore, when the lens barrel part 3 is inserted into the adapter main body 36, the front end part 12 c of the outer cylinder 12 comes into contact with the inclined surface 33 b of the protruding part 33.

  In a state in which the protruding portion 34 is in a position facing the concave portion 39, a gap D <b> 2 is formed between the outer surface of each plate body 32 and the inner peripheral surface of the fastening cylinder 30, and thus each plate body 32. Can be bent outward. Further, the depth of the recess 39 is such that the protrusion 34 is bent outward and the protrusion 34 is not in contact with the recess 39 even when the outer surface of each plate 32 is in contact with the inner peripheral surface of the fastening cylinder 30. Is formed. Therefore, when the lens barrel 3 is inserted into the adapter main body 36, if the front end 12 c of the outer tube 12 contacts the inclined surface 33 b of the protrusion 33, the protrusion 33 guides the front end 12 c of the outer tube 12. Then, the distance L3 between the apexes of the projecting portions 33 of the plate bodies 32 facing each other widens outward. As shown in FIG. 9, the protruding portion 33 comes into contact with the outer peripheral surface of the outer tube 12, and the lens barrel portion 3 can be inserted into the adapter main body 36. The innermost peripheral diameter R2 of the fastening cylinder 30 is set larger than the outer peripheral diameter of the outer cylinder 12 so that the outer cylinder 12 can pass through.

  When the lens barrel 3 is inserted into the adapter main body 36 until the front end 12c of the exterior cylinder 12 contacts the positioning protrusion 20 (not shown), the protrusion 33 is re-energized by the elastic restoring force of each plate 32. As shown in FIG. 8, it protrudes to the rear side of the end surface of the rear end portion 12b of the exterior cylinder 12. Therefore, each plate body 32 is in a straight state in which the inner surface is in contact with the outer peripheral surface of the exterior cylinder 12.

  The inner diameter R2 of the opening 30a, which is the innermost peripheral diameter of the rear end portion 40a of the inclined surface 40 of the tightening cylinder 30, is the plate bodies facing each other vertically and horizontally when no force is applied to each plate body 32. 32 is set to be smaller than an interval (diameter of a circle in contact with each front end portion 34b) L4 at the front end portion 34b of the outer surface 34a of the projecting portion 34. Therefore, when the fastening cylinder 30 is displaced forward with respect to the adapter main body 36, the inclined surface 40 comes into contact with the outer side surface 34 a of the protruding portion 34 of each plate body 32. That is, the inclined surface 34a and the inclined surface 40 are formed to have surfaces that overlap each other in the front-rear direction.

  Note that the distance L5 (diameter of a circle in contact with each rear end portion 34c) L5 at the rear end portion 34c of the outer surface 34a of the protruding portion 34 of each plate body 32 facing in the vertical and left and right directions is the inclined surface 40 of the fastening cylinder 30. Is set smaller than the inner diameter R3 of the front end portion 40b. Therefore, when the tightening tube 30 is displaced forward with respect to the adapter main body 36, the rear surface in the recess 39 is not caught by the rear surface of the protrusion 34, and the tilt of the tightening tube 30 is inclined. The fastening tube 30 can be displaced forward so that the surface 40 contacts the outer surface 34 a of the protruding portion 34.

  As described above, the lens barrel 3 is inserted into the adapter main body 36 until the front end 12c of the outer cylinder 12 contacts the positioning projection 20 (not shown), and then the clamping cylinder 30 is rotated to tighten it. The attached tube 30 is fastened to the adapter main body 36. That is, the fastening cylinder 30 is rotated in a direction in which the amount of screw coupling between the male screw 35 and the female screw 37 is increased, and the fastening cylinder 30 is displaced forward relative to the adapter body 36 to obtain the state shown in FIG. To do.

  When the tightening tube 30 is tightened with respect to the adapter main body 36 and the tightening tube 30 is displaced forward with respect to the adapter main body 36, the inclined surface 40 on the tightening tube 30 side becomes the outer surface of the projecting portion 34. Abuts on 34a. Since both the inclined surface 40 and the outer surface 34a are inclined from the outer side toward the inner side, the outer surface 34a of the protrusion 34 is pressed inward from the inclined surface 40 as the fastening cylinder 30 is displaced forward. You will gradually receive power. That is, each plate body 32 is pressed against the outer tube 12, and the adapter main body 36 is fixed to the lens barrel 3.

  In this manner, the optical adapter 28 is fixed to the lens barrel portion 3 by sandwiching the outer tube 12 with the inner surface of each plate 32. That is, since it is not necessary to provide a configuration for fixing the optical adapter 28 on the exterior tube 12 side, there is a limit to the arrangement and size of components such as the lens 5 and the image sensor 6 inside the lens barrel 3. The optical adapter 28 can be attached to the lens barrel 3 without giving or inviting an increase in the diameter of the lens barrel 3.

  The inclined surface 40 on the side of the fastening cylinder 30 and the outer surface 34a of the protruding portion 34 are inclined surfaces having the same inclination in the front-rear direction, and are arc surfaces having the same curvature in the circumferential direction of the central axis M. Therefore, the inclined surface 40 and the outer surface 34a can be in surface contact with each other over a wide area, and a pressing force acts on the outer surface 34a from the inclined surface 40 with certainty.

  In the second embodiment, the abutting portion is formed by the inclined surface 40 and the outer surface 34a. However, one of the inclined surface 40 and the outer surface 34a is not an inclined surface but a protrusion. The apex of the protrusion may be in contact with the other inclined surface.

  Further, the inner side surface of each plate 32 is flush with the inner peripheral surface of the lens barrel holding portion 31. Therefore, the entire inner surface of each plate 32 abuts against the outer peripheral surface of the exterior cylinder 12. Therefore, when each plate 32 is pressed against the exterior cylinder 12 by the inclined surface 40 of the tightening cylinder 30 via the protrusion 34, the entire inner surface of each plate 32 is against the exterior cylinder 12. Therefore, the optical adapter 28 is securely fixed to the exterior cylinder 12.

  As shown in FIG. 8, in a state where the optical adapter 28 is fixedly attached to the lens barrel portion 3, the projecting portion 33 is disposed on the rear side of the end surface of the rear end portion 12 b of the exterior tube 12. Become. Further, since the outer surface 34a of the projecting portion 34 receives the pressing force directed inward by the inclined surface 40, the projecting portion 33 is prevented from being displaced outward. By the way, the screw connection between the tightening tube 30 and the adapter main body 36 is loosened, and the force that each plate 32 sandwiches the outer tube 12 is weakened, and the optical adapter 28 moves in the front-rear direction with respect to the outer tube 12. It may happen that it will be in a state where it ends up. Even in such a case, the projecting portion 33 is disposed on the rear side of the rear end portion 12b of the exterior tube 12 in a state in which the outward displacement is prevented, so that the projecting portion 33 becomes the exterior tube. 12, the optical adapter 28 can be prevented from falling off the lens barrel 3.

  In addition, when the screw connection between the tightening tube 30 and the adapter main body 36 is loosened, the adapter main body 36 rattles against the lens barrel portion 3, so that the image of the mirror surface 19c reflected on the monitor 2a is blurred. Therefore, it is possible to know that the screw connection between the tightening cylinder 30 and the adapter main body 36 has been loosened by the blurring of the image. Then, before the optical adapter 28 is detached from the lens barrel 3, the optical adapter 28 attached to the lens barrel 3 can be pulled out from the inside of the mechanical device or the body cavity to the outside. It is possible to prevent an accident in which the adapter 28 is left inside the mechanical device or the like.

  As described above, the protrusion 33 is disposed on the rear side of the rear end portion of the outer tube 12 in a state in which the outward displacement is prevented, so that the protrusion 33 is the rear end portion of the outer tube 12. Since it engages with 12b, it is not necessary to provide a configuration for preventing the optical adapter 28 from falling off on the exterior tube 12 side. Therefore, there is no limitation on the arrangement and size of components such as the lens 5 and the imaging element 6 inside the lens barrel portion 3, and the diameter of the lens barrel portion 3 is not increased. It is possible to prevent the optical adapter 28 from falling off.

  As shown in FIG. 8, in a state where the optical adapter 28 is fixedly attached to the lens barrel portion 3, a gap S2 is, for example, 1 mm between the protruding portion 33 and the rear end portion 12b of the exterior tube 12. The position where the protrusion 33 is formed is set so as to be formed as an interval. As described above, by providing the gap S2 between the projecting portion 33 and the rear end portion 12b of the exterior cylinder 12, even if there is some variation in the length of the exterior cylinder 12 in the front-rear direction, the exterior cylinder 12 The rear end portion 12 b can be positioned in front of the protruding portion 33.

  The inclined surface 33 a of the protruding portion 33 is an arc-shaped surface in the circumferential direction of the central axis M. Therefore, when the protrusion 33 is engaged with the rear end portion 12b of the exterior cylinder 12, the protrusion 33 is engaged along the arc of the rear end portion 12b of the exterior cylinder 12, and the engagement is performed. It can be certain.

  Next, an operation for removing the optical adapter 28 attached and fixed to the lens barrel 3 as described above from the lens barrel 3 will be described.

  First, the tightening cylinder 30 is rotated in a direction to weaken tightening of the screw connection with the adapter main body 36, and the recess 39 is displaced rearward to a position facing the protruding portion 34 as shown in FIG. In this state, each plate 32 can be bent outward by the presence of the gap D <b> 2 between the fastening cylinder 30 and each plate 32.

  Therefore, when the lens barrel part 3 is moved rearward, the inclined surface 33b of the protrusion 33 is guided by the rear end part 12b of the exterior cylinder 12, and the distance L3 between the apexes of the protrusions 33 facing each other of the plate bodies 32 is obtained. Is expanded. Then, as shown in FIG. 9, the protruding portion 33 is positioned on the outer peripheral surface of the exterior cylinder 12, and the lens barrel portion 3 can be pulled out from the adapter body 36 rearward.

  By the way, the interval L4 at the front end 34b of the outer side surface 34a of the projecting portion 34 of each plate body 32 facing in the vertical and horizontal directions is set to be larger than the inner diameter R4 of the inner peripheral surface on the front side of the recess 39 of the fastening cylinder 30. ing. That is, the front side surface 39a inside the recess 39 faces the front side surface 34d of the protruding portion 34 and serves as an engaging portion that prevents the optical adapter 28 from being separated.

  Thus, by providing the front side surface 39a, the adapter main body 36 and the fastening cylinder 30 are separated in a state where the lens barrel portion 3 is removed from the optical adapter 28, and either one of them is lost. Can be prevented. In addition, when the fastening cylinder 30 and the adapter main body 36 are assembled, each plate body 32 is bent inward so that it can be assembled smoothly.

  Further, in a state where the male screw 35 and the female screw 37 are screwed together, the front side surface 34d is set to the front side surface 39a by setting the positional relationship in which the front side surface 39a of the recess 39 and the front side surface 34d of the protruding portion 34 are engaged. In the engaged state, it is prevented that the tightening cylinder 30 is rotated in a direction in which the screw connection between the male screw 35 and the female screw 37 is reduced, so that the adapter body 36 and the tightening cylinder 30 are not easily separated. .

  The optical adapters 8 and 28 in each of the above-described embodiments have a function for changing the photographing direction, but may be an optical adapter having a conversion lens for changing the focal length of the photographing lens 5.

  Moreover, although each plate body 22 and 32 is provided in four places one each on the upper and lower sides, and right and left, you may make it provide not only this but three places or five places or more from one place. Preferably, the optical adapters 8 and 28 are stably attached to the exterior cylinder 12 by being disposed at two or more locations that are symmetrically disposed with respect to the central axis in the direction along the central axis M of the exterior cylinder 12. Can be fixed to.

  Further, the protrusions 23 and 33 do not need to be provided on each of the plate bodies 22 and 32, and may be provided on at least one plate body 22 and 32. Preferably, by disposing at two or more locations that are symmetrical with respect to the central axis in the direction along the central axis M of the outer tube 12, Dropout can be effectively prevented.

1 is a configuration diagram showing an overall configuration of an endoscope apparatus to which an optical adapter according to each embodiment of the present invention is attached. It is a figure which shows the optical adapter which concerns on the 1st Embodiment of this invention, and is a side view of the optical adapter with which the lens-barrel part of the endoscope apparatus shown in FIG. 1 was mounted | worn. 3 is a diagram showing a configuration of an adapter main body of the optical adapter shown in FIG. 2, FIG. 3 (a) is a side view of the adapter main body, and FIG. 3 (b) is a rear view of the adapter main body viewed from the rear. It is. FIG. 3 is a side sectional view of the optical adapter and the lens barrel in a state where the lens barrel is inserted into the optical adapter shown in FIG. 2, and shows a state where the optical adapter is not fixed to the lens barrel. FIG. 3 is a side sectional view of the optical adapter and the lens barrel in a state where the lens barrel is inserted into the optical adapter shown in FIG. 2 and the optical adapter is fixed to the lens barrel. It is an enlarged view of the A part of FIG. FIG. 6 is a partial side sectional view of the optical adapter and the lens barrel portion showing a state in which the lens barrel portion is inserted into the optical adapter according to the second embodiment of the present invention, and the optical adapter is fixed to the lens barrel portion. It is a figure which shows the state which is not. It is a partial side sectional view of an optical adapter and a lens barrel part showing a state where a lens barrel part is inserted into an optical adapter according to a second embodiment of the present invention and the optical adapter is fixed to the lens barrel part. . In the optical adapter which concerns on the 2nd Embodiment of this invention, the optical adapter which shows the state in the middle of inserting a lens-barrel part or removing an optical adapter from a lens-barrel part, and a partial side sectional view of a lens-barrel part is there. FIG. 8 is an enlarged view of a portion B in FIG. 7.

Explanation of symbols

1 ... Endoscopic device.
8, 28 ... Optical adapters 9 and 36 ... Adapter body 12 ... Exterior cylinders 15 and 30 ... Tightening cylinder 20 ... Positioning projection 21 ... Male screw (screw coupling portion)
22, 32 ... Plate bodies 23, 33 ... Projections 23a, 33a ... Inclined surfaces 23b, 33b ... Inclined surfaces 24, 27a, ... Inclined surfaces (contact portions)
25 ... Female thread (screw joint)
34a, 40 ... Inclined surface (contact portion)
35 ... Male thread (screw joint)
37 ... Female thread (screw joint)
39a ... Front side (engagement part)

Claims (10)

In the optical adapter that is detachably attached to the lens barrel provided at the distal end of the endoscope device,
An adapter body into which the lens barrel is inserted;
The adapter body is inserted, and a fixed cylinder that is displaceable in the front-rear direction relative to the adapter body;
Provided in the adapter body, and provided with a protruding portion facing the stepped portion on the rear end side of the lens barrel portion,
The protruding portion is prevented from being displaced outward from a position facing the stepped portion on the rear end side of the lens barrel portion by the fixed tube when the fixed tube is displaced forward. Optical adapter. In the optical adapter that is detachably attached to the lens barrel provided at the distal end of the endoscope device,
An adapter body into which the lens barrel is inserted;
The adapter body is inserted, and a fixed cylinder that is movable in the front-rear direction relative to the adapter body;
A plate extending rearward from the adapter body;
Abutting portions that are provided on the inner side surface of the fixed cylinder and the outer side surface of the plate body, and that are in contact with each other;
A protrusion that is provided on the plate and is located on the rear side of the step portion on the rear end side of the lens barrel portion and protrudes inward when the lens barrel portion is inserted to a predetermined position of the adapter body. With
At least one of the contact portions is an inclined surface that is inclined from the outside to the inside from the front to the rear.   The front surface of the protrusion is formed as an inclined surface inclined from the outside to the inside from the front to the rear, and the rear surface is an inclined surface inclined from the inside to the outside from the front to the rear. The optical adapter according to claim 1, wherein the optical adapter is formed.   On the inner side surface of the adapter body, there is provided a positioning projection that protrudes inward and contacts the front end of the lens barrel, and the front end of the lens barrel is in contact with the positioning projection. The optical adapter according to any one of claims 1 to 3, wherein a gap is provided between a rear end portion of the lens barrel portion and the protruding portion.   The optical adapter according to claim 2, wherein the abutting portions are in surface contact with each other.   The shape along the circumferential direction of the lens barrel portion of the plate body is a shape along the circumferential shape of the outer peripheral surface of the lens barrel portion. Optical adapter.   The optical adapter according to any one of claims 2 to 6, wherein an inner surface of the plate body and an inner peripheral surface of an adapter main body other than the plate body are flush with each other.   A protruding portion is provided on the outer surface of the plate body, and an engaging portion that engages with the protruding portion is formed on the fixed cylinder on the front side of the protruding portion. The optical adapter according to any one of claims 2 to 7.   The adapter main body and the fixed cylinder have a screw coupling portion that is screw-coupled to each other, and the fixed cylinder moves relative to the adapter main body in the front-rear direction by a lead of the screw coupling portion. The optical adapter according to any one of claims 2 to 8.   An endoscope apparatus comprising the optical adapter according to any one of claims 1 to 9.

Images