JP3370435B2 - Rigid endoscope - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rigid endoscope for observing an observation image transmitted by a relay optical system through an eyepiece optical system. 2. Description of the Related Art In order to observe the throat and the like, a rigid endoscope in which a distal end of an insertion portion is greatly curved is used. In such a rigid endoscope, an eyepiece optical system is built in at a base end side of a lens frame having a built-in relay optical system for transmitting an observation image from a distal end side to a base end side of an insertion portion. An eyepiece is provided, and a plurality of adjustment mechanisms are provided in the vicinity of a connection portion between the two optical systems in order to perform various optical adjustments. In such a case, the adjusting portion is generally biased in the axial direction by a coil spring, and conventionally, a biasing coil spring is provided independently for each of the adjusting mechanisms. However, providing a biasing coil spring for each of the plurality of adjusting mechanisms of the optical system not only complicates the mechanism but also requires a very small and lightweight mechanism. There is a disadvantage that the rigid endoscope becomes large. SUMMARY OF THE INVENTION It is an object of the present invention to provide a rigid endoscope in which a rigid endoscope having a plurality of adjustment mechanisms in an optical system can be made small and lightweight. In order to achieve the above object, a rigid endoscope according to the present invention comprises a relay optical system for transmitting an observation image from a distal end to a proximal end of an insertion portion. In a rigid endoscope provided with an eyepiece having a built-in eyepiece optical system at a base end side of a built-in lens frame, a first optical adjustment member for performing optical adjustment of the optical system at one end side is provided. A spring is provided for urging in the direction of the optical axis and for urging a second optical adjusting member for performing another optical adjustment of the optical system in the other end side in a direction opposite to the above direction. . An embodiment will be described with reference to the drawings. FIG.
1 shows a rigid endoscope according to an embodiment of the present invention, in which an insertion section 1 formed in an elongated tubular shape having a circular cross section is formed such that a front half thereof is largely curved to about 70 to 80 degrees. ing. Since the insertion portion 1 is not flexible, its curved shape is always maintained. The proximal end of the insertion section 1 is connected to the proximal body 6. The hand-held side body 6 has a grip portion 2 for grasping and supporting with a hand, an eyepiece portion 3 for viewing an observation image transmitted through the inside of the insertion portion 1, and a protrusion from the tip of the insertion portion 1. A treatment tool insertion port 4 for feeding treatment tools to be performed,
Light guide flexible tubes 5 for transmitting illumination light are provided in a protruding manner. The hand-side main body 6 is formed of an electrically insulating synthetic resin, and the grip portion 2, the eyepiece portion 3, the treatment instrument insertion port portion 4, and the light guide flexible tube 5 are each watertight at hand. It is attached to the side body 6. As shown in FIG. 2 which is an enlarged cross section taken along the line II-II, the flexible light guide tube 5 protrudes laterally from the proximal body 6 and has a light guide fiber bundle (light) for illumination. (Not shown). Reference numeral 7 denotes a breaking rubber for preventing the base end of the light guide flexible tube 5 from being sharply bent. The grip portion 2 is detachably attached to the main body 6 from a slightly diagonally rearward downward direction. Reference numeral 10 denotes a metal mounting seat fixed to the hand side body 6 with screws, and a protruding portion formed on the mounting seat 10 is fitted into a concave portion formed on the grip portion 2. Then, as shown in FIG. 1, a fixing pin 11 having a protruding head is inserted across the through hole formed in the mounting seat 10 and the grip portion 2, thereby forming the grip portion 2. Are connected to the mounting seat 10. The distal end portion of the fixing pin 11 is screwed into a female screw formed on the grip portion 2. When the fixing pin 11 is tightened, the grip portion 2 is firmly fixed to the mounting seat 10. When the fixing pin 11 is loosened, the grip portion 2 can be removed from the main body 6 at the hand side. Therefore, when the user changes, the grip portion 2 can be replaced with the grip portion 2 having a size adapted to the hand of the user, and when the rigid endoscope is stored after use, the grip portion 2 is moved from the hand side main body 6. Can be stored in a small case having a small thickness. Further, since the mounting seat 10 to which the grip portion 2 is connected and fixed is supported by the electrically insulating hand-side main body 6 and does not contact other metal parts, the grip portion 2 and this rigid endoscope are used. The mirror is electrically insulated from other metal parts. As shown in FIG. 2, the proximal end of the light guide flexible tube 5 is fixed to the main body 6 via a connecting tube 12, and the right and left openings of the main body 6 have lids. 13,
14 are attached. An O-ring for sealing is mounted on a boundary surface between the parts facing the outside so that water does not enter the inside. Each O-ring is shown in a cross-sectional shape in a natural state before being mounted, and the reference numeral is omitted for each O-ring (the same applies hereinafter). As shown in FIG. 3, an observation window 17, an illumination window 18, and a treatment tool outlet 19 are arranged on the distal end surface of the insertion portion 1. A pair of illumination windows 18 are provided on the left and right, and an emission end of a light guide fiber bundle (not shown) is arranged inside the illumination windows 18. As shown in FIG. 4, an objective optical system 20 is disposed in the observation window 17, and an observation image of a subject obtained by the objective optical system 20 is transferred from the distal end to the proximal end of the insertion section 1. A relay optical system 21 for transmitting the light to the lens frame 22 is supported in the lens frame 22 and disposed in the insertion section 1. The lens frame 22 is an elongated rigid body formed by a hard metal pipe such as brass, for example, and is formed by different parts from a curved portion in the front half and a straight portion in the base half. The two parts are integrally connected by soldering or the like. The relay optical system 21 includes a number of lenses for transmitting an observation image and a prism for changing the direction of the optical axis in accordance with the curved shape of the lens frame 22. Each optical member is a mirror. It is adhesively fixed in the frame 22. Also, a treatment tool insertion channel 24 made of, for example, a fluororesin tube, whose base end is connected to the treatment tool insertion port 4, and a light guide fiber bundle (not shown) are inserted alongside the lens frame 22. It is inserted through the entire length of the part 1. The insertion portion 1 is covered with an outer tube made of a flexible tube 30. As shown in FIG. 5, the flexible tube 30 is an inner spiral tube 3 formed by winding a stainless steel strip spirally with a uniform diameter with a gap therebetween to form an elongated cylindrical shape.
1, an outer spiral tube 32 formed in a direction opposite to that of the spiral tube 31 and covered on the outer periphery of the spiral tube 31, and a plurality of stainless steel wires and the like are arranged side by side and braided into a cylindrical shape to form a spiral tube. A mesh tube 33 is provided on the outer periphery of the mesh tube 32, and an outer tube 34 made of a flexible polyurethane resin tube is provided on the outer periphery of the mesh tube 33. The flexible tube 30 is assembled in a straight state when sequentially covering each member. When the flexible tube 30 is completed, the flexible tube 30 is heated in a state of being curved so as to match the curvature of the lens frame 22. And a cooling process. As a result, as shown in FIG. 4, the flexible tube 30 has a curved shape that matches the curved shape of the lens frame 22 in the free state. Therefore, when the lens frame 22 is passed through the flexible tube 30, the flexible tube 30 is flexible. After the lens frame 22 is passed through the flexible tube 30 as shown in FIG. 4, the flexible tube 30 assumes a natural curved state in which no residual stress or the like remains. When the lens frame 22 is inserted into the flexible tube 30 in this manner, the shape of the insertion portion 1 is maintained by the lens frame 22. The flexible tube 30 can be moved by a small gap between the flexible tube 30 and the built-in body such as the lens frame 22, but cannot be deformed as a whole, and is inserted with a rigid mirror whose front half is curved. The outer tube of the part 1 is formed. FIG. 6 shows the distal end of the insertion portion 1 in an enlarged manner.
FIG. 7 shows a VII-VII section thereof. The lens frame 22 is attached to the metal distal end body 36 disposed at the distal end of the insertion section 1.
The distal ends of the treatment tool insertion channel 24 and the light guide fiber bundle 27 are inserted from behind and fixedly joined. The ends of the spiral tube 31, the spiral tube 32, and the mesh tube 33 of the flexible tube 30 are integrally fixed to a metal connecting ring 37 by, for example, soldering. The surface is watertight. Connecting ring 3
7 is screwed and fixed to the distal end portion main body 36 as shown in FIG. A metal tip cover 38 having an outer diameter gradually decreasing toward the front and formed in a smooth tapered shape is screwed around the outer periphery of the connection ring 37 to surround the periphery of the insertion portion 1. In. An O-ring for sealing is mounted on the inner surface side of the front cover 38. FIG. 8 shows a peripheral portion of the hand side main body 6. The treatment instrument insertion opening 4 is fixed obliquely protruding from the proximal body 6, and has an O-ring for sealing mounted on its fitting surface to prevent water from entering the inside of the fitting portion. It is blocking. As shown in FIG. 8, a metal connecting portion 41 for connecting the insertion portion 1 and a metal connecting portion for connecting the eyepiece portion 3 are provided in front of and behind the main body 6 at the hand side. An eye connecting tube 42 is fixedly protruding in the optical axis direction. An O-ring for sealing is mounted on each of the fitting portions. In the vicinity of the protruding end of the insertion portion connecting tube 41, a metal base end cap 43 water-tightly attached to the base end side of the flexible tube 30 is fixed by a sharp screw 45. The periphery of the connecting portion is surrounded by a base cover 44 screwed to the outer periphery of the insertion portion connecting tube 41. Inside the base cover 44, water is prevented from entering the connecting portion by the sharp screw 45. An O-ring for sealing is mounted. IX-IX
As shown in FIG. 9 showing a cross section, a hole 46 for passing the lens frame 22, a hole 47 for passing a connection pipe 50 communicatively connected to the proximal end of the treatment instrument insertion channel 24, and a light guide fiber bundle. A hole 48 for passing 27 is formed. The proximal end of the connection pipe 50 is connected to the treatment instrument insertion port 4 and is fixed thereto by silver brazing or the like. The distal end of the connection pipe 50 is connected to the treatment instrument insertion channel 24.
And is bound by a metal wire from around the treatment tool insertion channel 24. The exposed portion of the connection pipe 50 in the hand side main body 6 is covered with an electrically insulating fluororesin tube (insulating tube) 51. Therefore, the treatment instrument insertion opening 4 and the connection pipe 50 are electrically insulated from other metal parts of the rigid endoscope. As shown in FIG. 9, a hole 46 for passing the lens frame 22 is formed to be slightly thicker than the diameter of the lens frame 22, and a small screw arranged toward the center of the hole 46 from three directions. A slightly thinner tip of the (optical axis alignment coarse adjustment small screw) 53 is in contact with the surface of the lens frame 22. Mirror frame 2
On the second side, a groove 54 into which the tip of the small screw 53 fits is formed. Therefore, by adjusting the degree of tightening of the three small screws 53, the axial position of the lens frame 22 can be shifted, and the relay optical system 21 built in the lens frame 22 and the eyepiece 3 can be built in. Coarse optical axis adjustment with the eyepiece optical system 60 that has been performed can be performed. The rotation of the lens frame 22 is also restricted by fitting the tip of the small screw 53 into the groove 54 on the outer periphery of the lens frame 22. A metal supporting cylinder 61 is mounted on the projecting end of the eyepiece connecting cylinder 42 so as to protrude therefrom, and is fixed to the eyepiece connecting cylinder 42 by screws (not shown). The eyepiece frame 62 supporting the eyepiece optical system 60 is fitted into the support cylinder 61 so as to be slidable in the optical axis direction. O-rings for sealing are mounted on the fitting portions and the like. An insulating cylinder 63 made of an electrically insulating material is covered on the base end portion of the lens frame 22 in a cap shape.
Therefore, the lens barrel 22 is electrically connected to the distal end body 36 at the distal end side, but is electrically insulated from the eyepiece section 3 at the proximal end side by the insulating cylinder 63. The insulating cylinder 63 is disposed so as to be loosely fitted to the eyepiece connecting cylinder 42 so that a slight gap is formed in the radial direction. 64 are fixed. A V-shaped groove 65 is formed in the outer peripheral surface of the receiving ring 64 in the circumferential direction, and is screwed to the eyepiece connecting cylinder 42 as shown in FIG. A sharp screw (sharp screw for fine adjustment of optical axis alignment) 66 is tightened toward the V groove 65 from three directions. However, since the width of the V-groove 65 is slightly larger than the tip of the sharp screw 66, the lens frame 22 is fixed in the axial direction even if the sharp screw 66 is tightened. Never. Therefore, by adjusting the degree of tightening of the three sharp screws 66, the axial position of the lens frame 22 is finely moved, and the fine optical axis alignment between the relay optical system 21 and the eyepiece optical system 60 is performed. Adjustments can be made. On the inner peripheral surface of the protruding end of the eyepiece connecting cylinder 42,
A male screw portion 68a formed on the outer periphery of the end of the focus adjustment cylinder 68 also shown in FIG. Focus adjustment barrel 6
At the end at the back of 8, a comb-shaped uneven portion 68b for engaging a tool is formed. A focus adjusting lens 70 has a relay optical system 21 and an eyepiece optical system 60 inside the protruding end of the focus adjusting barrel 68.
And is fixed coaxially. Therefore, a small driver-like tool is inserted through the adjustment window 71 formed on the side surface of the support cylinder 61, and the tip of the tool is inserted into the uneven portion 6 of the focus adjustment cylinder 68.
By rotating the focus adjustment barrel 68 around the axis by engaging with the focus adjustment lens 8b, the focus adjustment lens 70 advances and retreats in the optical axis direction, and focus adjustment can be performed. 74 is a cover cylinder provided so as to surround the adjustment portion. In this mechanism, a first compression coil spring 72 is mounted between the receiving ring 64 and the focus adjustment cylinder 68 so as to urge the two in the direction of the optical axis to move them away from each other. Accordingly, the focus adjusting cylinder 68 is moved by the one end of the first compression coil spring 72 to the eyepiece optical system 6.
Since it is always urged in the zero direction, the focus does not shift due to the backlash of the male screw portion 68a during the fine adjustment of the focus. Since the lens frame 22 is urged in the distal direction by the other end of the first compression coil spring 72, the side wall surface of the groove 54 is pressed against the side surface of the distal end portion of the small screw 53. In addition, no axial displacement occurs during the coarse and fine adjustment of the optical axis alignment. The eyepiece frame 62 is urged outward by a second compression coil spring 76 whose one end is received by a spring receiver 77. A pin 78 protruding from the side wall of the eyepiece frame 62 is passed through a cam hole 79 formed in the side wall of the support cylinder 61 to engage with a vertical groove 81 formed on the inner surface of the diopter adjusting ring 80. I agree. Therefore, the pin 78 is constantly pressed against one slope of the cam hole 79 by the urging force of the second compression coil spring 76, and the position of the pin 78 is adjusted by rotating the diopter adjusting ring 80. Changes, the eyepiece frame 62 supporting the eyepiece optical system 60 moves in the optical axis direction, and diopter adjustment is performed. Reference numeral 82 denotes a nut for holding the diopter adjusting ring 80 so as to be rotatable and not to move in the axial direction. An O-ring for sealing is mounted on the rotating sliding surface of the diopter adjusting ring 80 and the like. According to the present invention, the first optical adjustment member is urged in the optical axis direction at one end, and the second optical adjustment member is biased at the other end.
By providing a spring that biases the optical adjustment member in the opposite direction, it is possible to bias two optical adjustment members with one spring, so a rigid endoscope having a plurality of adjustment mechanisms in the optical system It has an excellent effect that it can be made compact and lightweight.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall side view in which a part of an embodiment of the present invention is cut away. FIG. 2 is an enlarged sectional view taken along the line II-II of the embodiment of the present invention. FIG. 3 is a front view of an insertion portion according to the embodiment of the present invention. FIG. 4 is a side sectional view of an insertion portion according to the embodiment of the present invention. FIG. 5 is a partially exploded perspective view of the flexible tube according to the embodiment of the present invention. FIG. 6 is an enlarged side sectional view of the distal end of the insertion portion according to the embodiment of the present invention. FIG. 7 is a sectional view taken along line VII-VII of the embodiment of the present invention. FIG. 8 is a side sectional view of a proximal portion of the embodiment of the present invention. FIG. 9 is a sectional view taken along line IX-IX of the embodiment of the present invention. FIG. 10 is a sectional view taken along line XX of the embodiment of the present invention. FIG. 11 is a perspective view of a focus adjustment cylinder according to the embodiment of the present invention. [Description of Signs] 22 Lens frame 68 Focus adjustment barrel 72 Coil spring

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-282815 (JP, A) JP-A-1-232320 (JP, A) JP-A-62-132512 (JP, U) (58) Survey Field (Int.Cl. ⁷ , DB name) A61B 1/00-1/32

Claims (1)

(57) [Claims 1] A proximal end of a lens frame having a built-in relay optical system for transmitting an observation image from a distal end to a proximal end of an insertion portion.
In a rigid endoscope provided with an eyepiece having a built-in eyepiece optical system, a first end for performing optical adjustment of the optical system on one end side
A spring is provided for urging the optical adjustment member in the optical axis direction, and for urging the second optical adjustment member for performing another optical adjustment of the optical system in the opposite direction to the other direction on the other end side. A rigid endoscope characterized in that: