JP3549321B2 - Endoscope - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an endoscope capable of adjusting a positional relationship between an objective optical system and a light receiving unit and thereby performing focusing.
[0002]
[Prior art]
The endoscope includes a body having a hollow base portion and a hollow insertion portion extending forward from the base portion. An objective optical system is housed at the distal end of the insertion section. An image sensor (light receiving means) such as a CCD is arranged behind the objective optical system. A signal line (image transmission means) is connected to the image sensor, and the signal line passes through the insertion section and is led to the outside through the base section. An image of the observation target is captured by an image sensor via an objective optical system, and the image signal is sent to a processing device via a signal line, where it is converted into a television signal and displayed on a television.
[0003]
[Problems to be solved by the invention]
In the above-described conventional general endoscope, the positional relationship between the objective optical system and the light receiving means is constant, and the focusing cannot be performed according to the distance to the observation target. Therefore, an endoscope capable of focusing has been developed, but none has been satisfactory.
[0004]
For example, in an endoscope disclosed in Japanese Utility Model Publication No. 46-18123, a holder for holding the distal end of an optical fiber bundle (image transmission means) is accommodated in the insertion portion so as to be movable in the axial direction. This holder is forbidden from rotating by pins. On the other hand, a see-saw type operation member is provided on the body, and by operating this operation member, the position is adjusted by moving the holder via a wire, and thus the position of the tip end surface (light receiving means) of the optical fiber bundle is adjusted. Focusing is performed by adjusting the position with respect to the objective optical system. However, with this endoscope, only two positions, a front position and a rear position, can be selected as the position of the holder, and fine adjustment cannot be performed, so that high-accuracy focusing cannot be expected.
[0005]
Further, in the endoscope disclosed in FIG. 2 of Japanese Utility Model Laid-Open Publication No. 60-16115, the rear end of an image guide (image transmission means) formed by fixing and integrating an optical fiber bundle is fixed to an eyepiece. . The eyepiece is inserted so as not to rotate with respect to the body and to slide in the axial direction. In this configuration, the axial position of the distal end surface (light receiving means) of the rigid image guide is adjusted with respect to the objective optical system by moving the eyepiece in the axial direction with respect to the body. However, fine adjustment is difficult because the axial movement amount of the eyepiece is the position adjustment amount of the distal end surface of the image guide as it is. Further, since there is no means for holding the adjustment position of the image guide, it is necessary to always hold the eyepiece by hand, and the operation is complicated.
[0006]
JP-A-60-16115 also describes another embodiment in which the eyepiece is screwed into a body. However, in this embodiment, the position of the tip surface of the image guide can be finely adjusted. However, the image guide is rotated at the time of this position adjustment, and the positional relationship between the top, bottom, left, and right in the field of view changes. was there.
[0007]
[Means for Solving the Problems]
According to the first aspect of the present invention, (a) a body having a hollow rigid insertion portion extending long, and (b) an illumination light having a tip portion disposed inside the tip portion of the insertion portion and extending rearward through the insertion portion. Transmission means; (c) an objective optical system arranged in the distal end of the insertion portion; and (d) light receiving means arranged behind the objective optical system and receiving reflected light from the observation target through the objective optical system. (E) image transmission means for passing the image information received by the light receiving means through the insertion section, (f) a holder for holding the light receiving means, and (g) the holder for the objective optical system. Position adjusting means for adjusting the position of the holder in the axial direction with respect to the insertion portion, wherein the position adjusting means axially moves the holder with respect to the insertion portion and locks the holder non-rotatably. A locking means and a holder extending in the axial direction of the insertion portion and having a distal end portion An adjusting member screwed to the rear end; and a second locking means for locking the adjusting member rotatably with respect to the body so as not to move in the axial direction. Accordingly, the position of the holder is adjusted in the axial direction, the holder and the adjusting member are formed in a tubular shape, and the image transmission means is inserted through the inside of the tube.
[0008]
Claim 2 is: (A) a body having a hollow rigid insertion portion that extends long; (B) a guide tube that extends through the insertion portion and extends in the axial direction; and (C) a tip portion is a tip of the insertion portion. Illuminating light transmitting means disposed in the section and extending rearward through the insertion section; (d) an objective optical system disposed in the distal end portion of the insertion section; and (e) disposed behind the objective optical system. Light receiving means for receiving reflected light from the observation object through the objective optical system; (f) image transmitting means for passing the image information received by the light receiving means through the guide tube to the rear; and (g) the guide tube. A holder which is inserted and holds the light receiving means; and (h) position adjusting means for adjusting the position of the holder in the axial direction with respect to the objective optical system, wherein the position adjusting means comprises: A third axially movable and non-rotatably locked relative to the guide tube. (Ii) an adjusting member which is inserted into the guide tube and extends in the axial direction, and a leading end portion of which is screwed to a rear end portion of the holder; and (iii) the adjusting member is attached to the guide tube. And a second locking means that is rotatable with respect to the axial direction and is locked so as not to move in the axial direction, and the position of the holder is adjusted in the axial direction with the rotation of the adjustment member.
The invention according to claim 3 is the endoscope according to claim 2, wherein the body has a base portion provided at a rear end of the insertion portion, and the insertion portion includes an outer tube and an inner tube, The illumination light transmitting means passes between the outer tube and the inner tube, and the guide tube passes through the inner tube and passes through the base.
[0009]
According to a fourth aspect of the present invention, in the endoscope according to the third aspect, the first locking means is accommodated in the accommodation hole having a non-circular cross section formed at the distal end portion of the guide tube, and is accommodated in the accommodation hole. And a head part of a holder having a non-circular cross section.
According to a fifth aspect of the present invention, in the endoscope according to the third aspect, the second locking means is provided in an annular groove formed on the outer periphery of the adjusting member and in a guide tube and inserted into the annular groove. And a plurality of pins.
According to a sixth aspect of the present invention, in the endoscope according to the third aspect, the second locking means includes a spring for urging the holder forward, and a protrusion provided on the adjustment member and abutting on the rear end of the guide tube. And a unit.
[0010]
According to a seventh aspect of the present invention, in the endoscope according to the third aspect, a rear end portion of the adjustment member projects outward from a rear end of the guide tube and is provided as a rotating operation portion.
According to an eighth aspect of the present invention, the endoscope according to the second aspect further includes an operating member that is rotatably inserted into the rear end portion of the guide tube so as to be axially immovable and rotatable. Part is provided as a rotating operation part protruding to the outside, and the distal end of the operating member and the rear end of the adjusting member are connected so as to be relatively axially movable and relatively unrotatable. Features.
According to a ninth aspect of the present invention, in the endoscope according to the third aspect, the guide tube is slidable in the axial direction and protrudes rearward of the base portion, and the objective optical system is supported in the support tube. The rear end of the support tube is detachably connected to the front end of the guide tube by screwing, and the front end of the support tube is locked by the insertion portion so as to restrict backward movement. .
[0011]
According to a tenth aspect of the present invention, in the endoscope including the components (a) to (g) of the first aspect, the objective optical system is supported in a support tube as one component of the position adjusting means, The position adjusting means further includes: first locking means for permitting the rotation of the support tube and locking the tip of the support tube to prohibit forward movement; and axially moving the holder with respect to the insertion portion. A second locking means that is movable and non-rotatably locked, a spring that urges the holder toward the support tube, and a rear end of the support tube and a front end of the holder that cooperate with each other to rotate the support tube. And cam means for adjusting the position of the holder in the axial direction with the movement.
[0012]
According to an eleventh aspect of the present invention, in the endoscope according to the tenth aspect, the first locking means includes a locking projection provided on the insertion portion and projecting radially and inward. The forward movement of the support tube is prohibited by locking the tip of the support tube to the portion, and moreover, a plurality of engagement recesses are formed at the tip of the support tube along the circumferential direction, The rotation position of the support tube is maintained by engaging one of the engagement concave portions with the locking convex portion.
According to a twelfth aspect of the present invention, in the endoscope according to the eleventh aspect, a passage groove extending in an axial direction is formed on an outer periphery of the support tube, and the passage groove is provided at a tip of an insertion portion of the support tube. It is characterized in that it is used to pass through the above-mentioned locking projection when inserting and removing the part.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIG. FIG. 1A shows a rigid endoscope. This rigid endoscope includes a hollow body 1. The body 1 has a rigid insertion portion 10 extending linearly, and a base portion 20 provided at a rear end of the insertion portion 10.
[0014]
The insertion portion 10 has a hard outer tube 11 and an inner tube 12 having a circular cross section and coaxial with each other. The distal ends of the outer tube 11 and the inner tube 12 coincide with each other. The inner space of the inner tube 12 is provided as a first accommodation space 13. The annular space between the outer tube 11 and the inner tube 12 coaxially surrounds the first housing space 13 and is provided as a second housing space 14. The rear end of the outer tube 11 is inserted and fixed to the front wall of the base 20. The rear end of the inner tube 12 passes through the internal space of the base 20 and is inserted and fixed to the rear wall of the base 20.
[0015]
An optical fiber bundle 30 (illumination light transmitting means) for transmitting illumination light is accommodated in the second accommodation space 14 and extends in the axial direction. The distal ends of the optical fiber bundle 30 substantially coincide with the distal ends of the outer tube 11 and the inner tube 12. The optical fiber bundle 30 passes through the base 20 from the rear end of the second housing space 14 and is led out, and the rear end is connected to a light source device (not shown).
[0016]
An objective unit 40 is housed at the tip of the first housing space 13. The objective unit 40 has a cylindrical support tube 41 and an objective optical system 42 housed and supported therein. The objective optical system 42 has a glass plate 42a, an aperture plate 42b, and a plurality of, for example, three lenses 42c in order from the front end of the support tube 41 to the rear. On the outer periphery of the distal end of the support tube 41, an annular locking projection 45 projecting in the radial and outward directions is formed. On the other hand, the inner tube 12 is formed with one or a plurality of locking projections 15 projecting radially and inward at positions slightly retreated from the distal end. These locking projections 45 and 15 constitute locking means for positioning. That is, when the locking projection 45 of the support tube 41 hits the locking projection 15 of the inner tube 12, the movement of the objective unit 40 is restricted and restricted to the rear. The distal end substantially matches the distal end of the insertion section 10.
[0017]
On the other hand, a cylindrical mounting tube 21 is mounted on the base portion 20. The mounting tube 21 is inserted into the rear end of the inner tube 12. A flange 21 a is formed at the rear end of the mounting cylinder 21, and the flange 21 a is fixed to a rear wall of the base 20. A screw hole 21b penetrating in the radial direction is formed in the flange portion 21a, and a screw 22 having an operation described later is screwed into the screw hole 21b.
[0018]
A guide tube 50 is inserted into the mounting cylinder 21 so as to be slidable and removable in the axial direction. The guide tube 50 is formed of a rigid tube, and extends coaxially with the insertion portion 10 in the first housing space 13 through the mounting tube 21. The rear end of the guide tube 50 protrudes rearward from the rear wall of the base portion 20 and the mounting cylinder 21, and a large-diameter knob portion 51 is formed there. The distal end of the guide tube 50 is connected to the rear end of the support tube 41 by screwing. A key 55 projecting radially and outwardly is fixed to the guide tube 50, and the key 55 is accommodated in an axially extending key groove 21 c formed on the inner surface of the mounting cylinder 21. Thus, when the screw 22 is loose, the guide tube 50 is movable in the axial direction and cannot rotate.
[0019]
In the guide tube 50, a tube-shaped holder 60 is housed in the front part, and a tube-shaped adjustment member 70 is housed in the rear part. The holder 60 has a head portion 61 at the tip thereof. The head portion 61 is formed in a non-circular shape, for example, a rectangular shape, and is housed in a housing hole 52 having a rectangular cross section (non-circular shape) formed at the end portion of the guide tube 50. ing. The head portion 61 and the accommodation hole 52 constitute a first locking means for locking the holder 60 so as to be axially slidable and non-rotatable with respect to the guide tube 50. In addition, although the spring 56 is accommodated in the accommodation hole 52 and urges the head portion 61 forward, the spring 56 may be omitted.
[0020]
The rear end of the adjusting member 70 protrudes from the rear end of the guide tube 50, and a large-diameter knob 71 (rotating operation unit) is formed there. The adjusting member 70 has an annular groove 72 on the outer periphery of the rear end portion. The tip of a pin 53 radially penetrating the knob 51 of the guide tube 50 enters the annular groove 72. The pin 53 and the annular groove 72Adjusting member 70The second locking means is configured to be rotatable with respect to the guide tube 50 (and, consequently, with respect to the body 1) and to be locked so as not to move in the axial direction. The rear end of the holder 60 and the front end of the adjusting member 70 are connected by screwing in the guide tube 50.
[0021]
Position adjustment for the holder 60, which will be described later, is performed by the first locking means including the head portion 61 and the receiving hole 52, the second locking means including the pin 53 and the annular groove 72, and the adjusting member 70. Means 5 is constituted.
[0022]
A concave portion 61a is formed on the tip end surface of the head portion 61 of the holder 60, and an image sensor 65 (light receiving means) such as a CCD is accommodated in the concave portion 61a. The tip of a signal line 66 (image transmission means) is connected to the image sensor 65. The signal line 66 is led out from the rear end through the holder 60 and the adjusting member 70. The rear end of the signal line 66 is connected to a monitor television via a processing device.
[0023]
In the above configuration, the objective unit 40 and the guide tube 50 are connected by screwing in a state where the locking projection 45 of the objective unit 40 is locked and positioned by the locking projection 15 of the insertion section 10, and The guide tube 50 is fixed to the base member 20 by the screw 22. As a result, the objective unit 40 is maintained at a predetermined position with respect to the body 10. In this state, when the adjustment member 70 is rotated by grasping the knob 71 of the adjustment member 70, the adjustment member 70 cannot move in the axial direction with respect to the base 20, and the holder 60 rotates with respect to the guide tube 50. Since it is immovable, the adjusting member 70 and the holder60Through the screw of the holder60Are axially adjusted. As a result, the holder60The position of the image sensor 65 held at the tip of the objective optical system 42 is adjusted in the axial direction with respect to the objective optical system 42, whereby focusing can be performed. By using the screwing of the holder 60 and the adjusting member 70, the minute position of the holder 60 can be adjusted by the turning operation of the adjusting member 70, and therefore, the focusing can be performed with high precision. it can. In addition, since the image sensor 65 does not rotate at the time of focusing, it is possible to avoid a change in the vertical and horizontal positions in the field of view, which does not hinder observation.
[0024]
The objective unit 40 is detachable from the insertion section 10 of the body 1, that is, can be replaced. In a state where the objective unit 40 is not mounted, the guide tube 50 is advanced with respect to the body 1 until the knob 51 contacts the rear wall of the base 20, and the tip thereof is positioned near the tip of the insertion unit 10. .
[0025]
When the objective unit 40 is mounted on the insertion section 10, the screw 22 is loosened so that the guide tube 50 can slide on the body 1. In this state, the objective unit 40 is brought close to the tip of the guide tube 50, and the rear end of the support tube 41 is screwed to the tip of the guide tube 50. This screwing is performed by turning the objective unit 40. At this time, the guide tube 50 is prevented from rotating by the key 55 and the key groove 21c.
[0026]
Next, the guide tube 50 is slid backward. At this time, the holder 60, the adjusting member 70, and the image sensor 65 also move together with the guide tube 50. Eventually, the locking projection 45 at the tip of the objective unit 40 hits the locking projection 15 of the inner tube 12, and the rearward movement of the objective unit 40 and the image sensor 65 is prohibited, and the positioning thereof is performed. At this position, the screw 22 is screwed in to fix the guide tube 50. In this positioning state, the tip of the objective unit 40 substantially matches the tip of the insertion section 10, and almost also matches the tip of the optical fiber bundle 30. Then, if the above-described focusing is performed after the mounting of the objective unit 40, the focusing can be performed on an observation target at an arbitrary distance.
[0027]
When the objective unit 40 is to be removed, the guide tube 50 is advanced by loosening the screw 22, and the objective unit 40 protruding from the distal end of the insertion section 10 is grasped by hand and turned. May be released.
[0028]
Instead of the objective unit 40, an objective unit 40A shown in FIG. In this objective unit 40A, components corresponding to those of the objective unit 40 in FIG. The objective optical system 42A of the objective unit 40A is for obtaining a wide-angle visual field, and a concave lens 42d is attached to the tip of the support tube 41A instead of the glass plate 42a. The axial dimension of the objective unit 40A is longer than the objective unit 40 of FIG. Therefore, when the objective unit 40A is mounted, the image sensor 65 is retracted from the distal end of the insertion section 10 as compared with the case of FIGS. Such a dimensional difference in the axial direction can be absorbed by sliding the guide tube 50. The objective unit 40A is positioned by the locking of the locking projections 45 and 15.
[0029]
After the replacement of the objective unit 40A, the focusing operation is performed by rotating the adjusting member 70 in the same manner as described above. In addition, as the objective unit, a unit for side view or the like can be used.
[0030]
Hereinafter, another embodiment of the present invention will be described. In these embodiments, constituent members corresponding to the preceding embodiments are denoted by the same reference numerals, and description thereof will be omitted.
FIG. 2 shows a second embodiment. In this embodiment, the holding means for the guide tube 50 is different from the first embodiment. The details will be described below.
[0031]
An annular spring receiving portion 58 forming a step is formed at an intermediate portion of the guide tube 50, and an annular spring receiving portion 16 projecting radially and inward is formed at an intermediate portion of the inner tube 11. ing. A compressed coil spring 80 is interposed between the spring receiving portions 58 and 16.
[0032]
A locking projection 59 is provided near the knob 51 of the guide tube 50. Further, an annular groove 25 and a passage groove 26 extending in the axial direction so as to pass from the annular groove 25 to the rear surface of the base portion 20 are formed on the inner peripheral surface of the base portion 20.
[0033]
In the above configuration, before the objective unit 40 is mounted, the guide tube 50 is at a position where the knob 51 is in contact with the rear surface of the base 20, that is, at a forward position, and exposes the image sensor 65 to the outside. At this time, the locking projection 59 of the guide tube 50 is housed in the annular groove 25 of the base portion 20, and the guide tube 50 is prohibited from moving rearward against the urging force of the coil spring 80. .
[0034]
Next, the objective unit 40 is screwed into the guide tube 50. After this screwing is completed, the guide tube 50 is turned so that the locking projection 59 is aligned with the passage groove 26. As a result, the guide tube 50 moves rearward by the urging force of the coil spring 80. Then, the locking projection 45 of the objective unit 40 is locked to the locking projection 15 of the inner tube 12, so that the backward movement of the objective unit 40 and the guide tube 50 is regulated, and the positioning of the objective unit 40 is reduced. Done.
[0035]
In this state, the coil spring 80 is in a compressed state, and constantly urges the guide tube 50 rearward. The guide tube 50 is stably supported because its rearward movement is restricted by the locking of the locking projections 15 and 45.
The focusing is the same as in the first embodiment.
[0036]
The third embodiment shown in FIG. 3 is significantly different from the first embodiment in that the guide tube 150 does not protrude to the rear of the base portion 20 and is connected to the rotating member 152. In addition, the rotating member 152 is provided as a part of the guide tube. The distal end of the guide tube 150 is connected to the rear end of the support tube 41 of the objective unit 40 by screwing. A key groove 150a is formed on the outer periphery of the guide tube 150. The key groove 150 a accommodates a key 17 that protrudes radially and inward from the inner peripheral surface of the inner tube 12. Thus, the guide tube 150 is not rotatable with respect to the insertion portion 10 but is movable in the axial direction.
[0037]
An annular spring receiving portion 150b extending radially and inward is formed a predetermined distance before the rear end of the guide tube 150. The inner tube 12 is further formed with a spring receiving portion 18 protruding radially and inwardly. A coil spring 85 for urging the guide tube 150 rearward is provided between the spring receiving portions 150b and 18. I have.
[0038]
On the other hand, the rotating member 152 is inserted through the base portion 20. The rear end of the rotating member 152 protrudes outward, and a large-diameter knob 152a is formed there. An annular groove 152b is formed in the knob 152a. When the pin 22m screwed into the base portion 20 enters the annular groove 152b, the rotating member 152 can only rotate and is prohibited from moving in the axial direction.
[0039]
The rear end of the guide tube 150 enters the front end of the rotating member 152, and both are linked by a cam mechanism 155. The cam mechanism 155 includes a pin 156 provided at the rear end of the guide tube 150 and protruding radially and outwardly, and a spiral groove 157 formed on the peripheral wall at the front end of the rotating member 152 to accommodate the pin 156. And
[0040]
In the above configuration, before the objective unit 40 is mounted, the pin 156 of the guide tube 150 is at or near the tip of the spiral groove 157 of the rotating member 152. As a result, the guide tube 150 is in the forward position, The image sensor 65 is located near the tip of the insertion section 10.
[0041]
In this state, the objective unit 40 is screwed to the distal end of the guide tube 150. At this time, since the rotation of the guide tube 150 is prohibited, the screwing can be advanced by turning the objective unit 40. After the screwing is completed, the rotating member 152 is turned. At this time, since the rotation of the guide tube 150 is prohibited as described above, the guide tube 150 moves rearward by the cam action of the spiral groove 157 and the pin 156. Eventually, the locking projection 45 of the objective unit 40 is locked to the locking projection 15 of the inner tube 12, so that the rearward movement of the objective unit 40 and the guide tube 150 is regulated, and the positioning of the objective unit 40 is reduced. Done.
[0042]
In this state, the coil spring 85 in the compressed state urges the guide tube 150 backward, so that the pin 156 hits the wall of the spiral groove 157, and the friction causes the guide tube 150 and the rotating member 152 to be in the above-mentioned locked position. It is supported stably.
Note that, similarly to the first embodiment, an objective unit 40A shown in FIG. 1B can be mounted instead of the objective unit 40.
[0043]
In the third embodiment, the adjusting member 171 is formed shorter than the adjusting member 70 of the first embodiment, and does not project outside. Adjusting member171Are inserted into the rotating member 152 and the guide tube 150.The adjusting member 171 and an operation member 172 described later are bothIt has a tubular shape, and allows the signal line 66 to pass therethrough. The adjusting member 171 is screwed with the rear end of the holder 60 at the front end. A locking flange 171x (convex portion) is formed at an intermediate portion of the adjusting member 171. The holder 60 and the adjusting member 171 are urged forward by the spring 56. When the locking flange 171x hits the rear end face of the guide tube 150, the adjusting member 171 moves in the axial direction with respect to the guide tube 150. Is prohibited and the rotation is allowed. Therefore, the spring 56 and the locking flange 171x constitute second locking means.
[0044]
A rear end portion of the adjusting member 171 is a rod portion 171a having a rectangular cross section. The rod portion 171a is inserted into an engagement hole 172a having a rectangular cross section formed at the distal end portion of the operation member 172. The rear end of the operation member 172 protrudes from the rear end of the rotation member 152, and a large-diameter knob 172b (rotation operation unit) is formed there. An annular groove 172c is formed in the outer periphery in the vicinity of the knob 172b, and the pin 53 provided on the rotating member 152 is inserted into the annular groove 172c, whereby the operating member 172 can rotate and rotate. It is locked so that it cannot move in the direction.
[0045]
In the third embodiment, focusing can be performed by turning the operation member 172. That is, when the operating member 172 is turned, the adjusting member 171 also rotates through the engagement between the engaging hole 172a and the rod portion 171a, and as a result, the holder 60 is pivoted through the screwing of the adjusting member 171 and the holder 60. The position is adjusted in the direction.
[0046]
When the objective unit 40 is mounted, when the guide tube 150 is retracted, the adjustment member 171 of the operation member 170 locked to the guide tube 150 via the locking flange 171x also moves rearward. The rearward movement of the adjustment member 171 is allowed by the engagement between the rod portion 171a and the engagement hole 172a.
[0047]
The fourth embodiment shown in FIGS. 4 to 6 is completely different from the first to third embodiments in that the focusing operation is performed at the distal end of the insertion section 10 side. The details will be described below. The holder 160 is much shorter than the insertion section 10 and is arranged near the tip of the insertion section 10. The inner tube 12 is used as a guide tube for guiding the holder 160 so as to be slidable in the axial direction. The holder 160 holds the image sensor 65 at the tip. A compressed coil spring 88 is interposed between the rear end of the holder 160 and an annular spring receiving portion 12x formed on the inner periphery of the inner tube 12, and the holder 160 is moved by the coil spring 88. It is biased forward.
[0048]
A key groove 161 extending in the axial direction is formed on the outer periphery of the holder 160, and a key 12y formed on the inner periphery of the inner tube 12 and protruding in the radial and inward directions is formed in the key groove 161. In. The key groove 161 and the key 12y constitute a second locking unit that locks the holder 160 so as to be able to move in the axial direction and not to rotate.
[0049]
In this embodiment, there is no guide tube, so the support tube 41B of the objective unit 40B is not screwed to the guide tube. In the present embodiment, the inner tube 12 plays a role of a guide tube for guiding the holder. An annular step 45 is formed near the tip of the support tube 41B. The step 45 is locked by a locking projection 12z that protrudes in the radial and inward directions formed on the inner peripheral surface near the distal end of the inner tube 12. The step 45 and the locking projection 12z constitute first locking means for restricting the forward movement of the support tube 41B.
[0050]
A large number of engaging recesses 45a are formed in the step 45 in the circumferential direction, and the rotational position of the support tube 41B is maintained by the engaging recesses 45a and the locking protrusions 12z as described later. A maintenance means for performing the operation is configured.
[0051]
A knob 46 (operation unit) for rotating the support tube 41B is formed on the distal end surface of the support tube 41B. A passage groove 49 extending in the axial direction is formed on the outer periphery of the support tube 41B.
[0052]
The rear end of the support tube 41B and the front end of the holder 160 are linked by cam means 90. The cam means 90 has an inclined cam surface 91 formed at the rear end of the support tube 41B, and a follower pin 92 formed on the outer periphery of the distal end of the holder 160 and projecting radially and outwardly. The follower pin 92 comes into contact with the inclined cam surface 91 by the force of the coil spring 88.
[0053]
In this embodiment, the support tube 41B, the spring 88, the first locking means including the step 45 and the locking projection 12z, the second locking means including the key groove 161 and the key 12y, and the engagement recess Position maintaining means for the holder 160 is constituted by the maintaining means consisting of 45a and the above-mentioned locking projection 12z, and the above-mentioned cam means 90.
[0054]
In the above configuration, when the objective unit 40B is not mounted, the holder 160 is at the forward position by the force of the coil spring 88, and the distal end floor pin 92 is locked by the locking protrusion 12z at the distal end of the inner tube 12.
[0055]
The objective unit 40B is mounted as follows. That is, the first housing space 13 is inserted from the opening at the distal end thereof against the coil spring 88. At this time, the insertion of the objective unit 40B becomes possible by passing the locking projection 12z through the passage groove 49. When the locking projection 12z comes off from the tip of the passage groove 49, the knob 46 is hooked on a finger and the support tube 41B is turned to lock the locking projection 12z and the step 45. In this state, the holder 160 and the objective unit 40B are urged forward by the force of the coil spring 88 in the compressed state, and the objective unit 40B is prohibited from moving forward. 40B is stably supported. Even when the objective unit 40B is removed, the locking projection 12z is passed through the passage groove 49. Also in the present embodiment, the objective unit 40B can be replaced with another objective unit, for example, a wide-angle objective unit, instead of the objective unit 40B.
[0056]
In the present embodiment, focusing is performed as follows. By slightly pushing the objective unit 40B, the engaged state between the locking convex portion 12z and the engaging concave portion 45a is released. As a result, the objective unit 40B becomes rotatable. Next, the knob 46a is hooked on a finger to rotate the objective unit 40B. Thereby, the contact position of the follower pin 92 against the inclined cam surface 91 changes, and the position of the holder 160 is adjusted in the axial direction. This adjustment position is stably maintained by engaging the locking projection 12z with one of the engagement recesses 45a.
[0057]
The present invention is not limited to the embodiments described above, and various modes are possible. For example, the adjustment member for focusing may be rotated by a motor provided inside or outside the body.
The fourth embodiment can be applied to an endoscope having a flexible insertion portion. In this case, only the distal end of the insertion portion is hard.
In all embodiments, the objective units may not be interchangeable. Further, the image transmission means may be an optical fiber bundle, and in this case, the front end surface of the optical fiber bundle serves as a light receiving means. An eyepiece may be provided on the base to view the image sent from the optical fiber bundle.
[0058]
【The invention's effect】
As described above, according to the first aspect of the present invention, the position of the holder can be adjusted in the axial direction by rotating the adjusting member, thereby adjusting the positional relationship between the light receiving means and the objective optical system, that is, focusing. Matching can be performed. In addition, since the screwing of the adjusting member and the holder is used, focusing can be performed with high accuracy. Further, at the time of focusing, the light receiving means does not rotate, so that the positional relationship between the top, bottom, left, and right of the field of view does not change, and there is no trouble in observation. Furthermore, since the image transmission means passes through the tubular holder and the adjusting member, the internal space of the insertion section can be effectively used, and the insertion section can be made thin.
According to the second and third aspects of the present invention, the position of the holder can be adjusted in the axial direction by rotating the adjusting member, whereby the positional relationship between the light receiving means and the objective optical system, that is, focusing is performed. Can be. In addition, since the screwing of the adjusting member and the holder is used, focusing can be performed with high accuracy. Further, at the time of focusing, the light receiving means does not rotate, so that the positional relationship between the top, bottom, left, and right of the field of view does not change, and there is no trouble in observation. Further, the holder and the adjustment member can be securely held via the guide tube.
According to the fourth aspect of the invention, the means for locking the holder so that it cannot rotate and can move in the axial direction can have a simple structure.
According to the fifth and sixth aspects of the present invention, the means for locking the adjustment member so as to be rotatable and immovable in the axial direction can have a relatively simple structure.
According to the invention of claim 7, focusing can be performed by a simple turning operation at the rear end of the adjusting member.
According to the eighth aspect of the invention, focusing can be performed by a simple rotation operation at the rear end of the operation member.
According to the ninth aspect of the present invention, the objective optical system can be replaced, and focusing can be performed after the replacement.
According to the tenth aspect, the position of the holder can be adjusted and the focus can be adjusted via the cam means by the rotation operation of the support tube.it can.
According to the eleventh aspect of the present invention, the rotation of the support tube can be restricted and the holder can be reliably maintained at the adjustment position by the simple configuration of the locking projection and the engagement recess.
According to the twelfth aspect of the present invention, the objective optical system can be replaced, and the focus can be adjusted after the replacement.
[Brief description of the drawings]
FIG. 1A is a longitudinal sectional view of an endoscope according to a first embodiment of the present invention. (B) is a longitudinal sectional view showing a different objective unit that can be mounted on the embodiment.
FIG. 2 is a longitudinal sectional view of an endoscope according to a second embodiment of the present invention.
FIG. 3 is a longitudinal sectional view of an endoscope according to a third embodiment of the present invention.
FIG. 4 is a longitudinal sectional view showing a distal end structure of an endoscope according to a fourth embodiment of the present invention.
FIG. 5 is a plan view showing the distal end structure of the endoscope of the fourth embodiment in a partial cross section.
FIG. 6 is a front view of a distal end structure of the endoscope according to the fourth embodiment.
[Explanation of symbols]
1 ... Body
5 Position adjustment means
10 ... insertion part
12 ... Inner tube (guide tube)
12y ... key (second locking means)
12z ... locking projection (first locking means, maintenance means)
30 Optical fiber bundle (illumination light transmission means)
41, 41A, 41B ... support tube
42, 42A ... Objective optical system
45 ... step (first locking means)
45a ... engaging recess (maintenance means)
46… knob (operation part)
50… Guide tube
52 ... accommodation hole (first locking means)
53 ... pin (second locking means)
56… Spring (second locking means)
60… Holder
61 head part (first locking means)
65… Image sensor (light receiving means)
66 ... signal line (image transmission means)
70… adjustment member
71… knob part (rotation operation part)
72 ... annular groove (second locking means)
88… Spring
150… Guide tube
161… keyway (second locking means)
171 ... adjustment member
172… operation member
171x ... locking flange (convex portion, second locking means)
172b: knob (rotating operation unit)
172c: annular groove (second locking means)

Claims (12)

(B) a body having a hollow rigid insertion portion extending long,
(B) an illumination light transmitting means having a distal end disposed within the distal end of the insertion portion and extending rearward through the insertion portion;
(C) an objective optical system disposed in the distal end of the insertion section;
(D) light-receiving means disposed behind the objective optical system and receiving reflected light from the observation target through the objective optical system;
(E) image transmission means for passing the image information received by the light receiving means through the insertion portion,
(F) a holder for holding the light receiving means,
(G) position adjusting means for adjusting the position of the holder relative to the objective optical system in the axial direction;
In the endoscope, the position adjusting means includes a first locking means for locking the holder axially movable and non-rotatably with respect to the insertion portion, and extending in an axial direction of the insertion portion. An adjusting member having a leading end portion screwed to a rear end portion of the holder; and a second locking means for locking the adjusting member so as to be rotatable with respect to the body so as not to move in the axial direction. An endoscope, wherein the position of the holder is adjusted in the axial direction with the rotation of the member, the holder and the adjusting member have a tubular shape, and the image transmission means is inserted into the inside of the endoscope. (B) a body having a hollow rigid insertion portion extending long,
(B) a guide tube that extends through the insertion portion and extends in the axial direction;
(C) an illumination light transmitting means having a distal end disposed at the distal end of the insertion portion and extending rearward through the insertion portion;
(D) an objective optical system disposed in the distal end of the insertion section;
(E) light-receiving means disposed behind the objective optical system and receiving reflected light from the observation target through the objective optical system;
(F) image transmission means for passing the image information received by the light receiving means backward through the guide tube ;
(G) a holder inserted into the guide tube and holding the light receiving means;
(H) position adjusting means for adjusting the position of the holder in the axial direction with respect to the objective optical system;
The provided, the positioning means is inserted (i) a first locking means for the holder to lock the non-rotatably and axially movable against the guide tube, (ii) the guide tube An adjusting member extending in the axial direction and having a distal end screwed to the rear end of the holder; and (iii) a second locking member for locking the adjusting member so as to be rotatable with respect to the guide tube and not to be movable in the axial direction. An endoscope having a locking means, wherein the position of the holder is adjusted in the axial direction with the rotation of the adjustment member. The body has a base portion provided at a rear end of the insertion portion, the insertion portion is formed of an outer tube and an inner tube, and the illumination light transmission means passes between the outer tube and the inner tube, The endoscope according to claim 2, wherein the guide tube passes through the inner tube and the base. The first locking means includes a receiving hole having a non-circular cross section formed at the distal end of the guide tube, and a head portion of a holder having a non-circular cross section received in the receiving hole. The endoscope according to claim 2 or 3 , wherein It said second locking means includes an annular groove formed on the outer periphery of the adjustment member, provided on the guide tube to claim 2 or 3, characterized in that it is composed of a pin inserted in the annular groove The endoscope as described. The said 2nd latching means is comprised with the spring which urges | biases a holder to the front, and the convex part provided in an adjustment member and contact | abutting the rear end of a guide tube, The Claim 2 or 3 characterized by the above-mentioned. The endoscope as described. 4. The endoscope according to claim 3, wherein a rear end of the adjustment member protrudes outside from a rear end of the guide tube and is provided as a rotation operation unit. 5. Further, an operation member is provided at the rear end of the guide tube so as to be axially immovable and rotatably inserted, the rear end of the operation member protruding to the outside and provided as a rotation operation portion, and The endoscope according to claim 2 , wherein a distal end portion and a rear end portion of the adjustment member are connected so as to be movable in a relative axial direction and not to rotate relatively. The guide tube is slidable in the axial direction and protrudes rearward of the base, the objective optical system is supported in the support tube, and the rear end of the support tube is detachably attached to the tip of the guide tube by screwing. 4. The endoscope according to claim 3, wherein the endoscope is connected, and a distal end of the support tube is locked by the insertion portion so as to restrict backward movement. 5. (B) a body having a hollow rigid insertion portion extending long,
(B) an illumination light transmitting means having a distal end disposed within the distal end of the insertion portion and extending rearward through the insertion portion;
(C) an objective optical system disposed in the distal end of the insertion section;
(D) light-receiving means disposed behind the objective optical system and receiving reflected light from the observation target through the objective optical system;
(E) image transmission means for passing the image information received by the light receiving means through the insertion portion,
(F) a holder for holding the light receiving means,
(G) position adjusting means provided on the distal end side of the insertion portion, for adjusting the position of the holder in the axial direction with respect to the objective optical system;
In an endoscope provided with
The objective optical system is supported in a support tube as one component of the position adjusting unit, and the position adjusting unit further allows the support tube to rotate and locks the distal end of the support tube to move forward. First locking means for inhibiting movement of the holder, second locking means for axially moving the holder with respect to the insertion portion and locking the holder non-rotatably, and biasing the holder toward the support tube. An endoscope comprising: a spring; and cam means for coordinating a rear end of the support tube and a front end of the holder to adjust a position of the holder in an axial direction as the support tube rotates. The first locking means includes a locking projection provided on the insertion portion and projecting in a radial direction and an inward direction. The front end of the support tube is locked by locking the tip of the support tube to the locking projection. In addition, a plurality of engaging recesses are formed along the circumferential direction at the distal end of the support tube, and one of the engaging recesses is engaged with the locking projection. The endoscope according to claim 10, wherein the rotation position of the support tube is maintained. A passage groove extending in the axial direction is formed on the outer periphery of the support tube, and this passage groove is used to pass the locking projection when the support tube is inserted into or removed from the distal end of the insertion portion. The endoscope according to claim 11, wherein the endoscope is used.

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