JPH1147075A - Object driving mechanism of endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the object driving mechanism of an endoscope capable of obtaining a focused and excellent endoscope observation image in the whole range of adjustment by moving an object frame in an axial line direction without inclining it by means of a remote operation with an operation wire thereby executing focusing and zooming. SOLUTION: When the operation wire 25 is pulled by the remote operation, a cam cylinder 50 is rotated and driven around an axial line by a slid cylinder 55 sliding in the axial line direction so that one of or both of the object frame 34 or/and image receiving part frame 35 are driven by it so as to execute focusing and zooming. Then, the energizing force of a second energizing means 58 for energizing the slide cylinder 55 to a tip side is made to be normally large by the energizing force of the first energizing means 47 for energizing the frames 34 and 35 in the axial line direction, which are inserted to a fixed cylinder 28 so as to be freely slidable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope objective driving mechanism having a function such as focusing or zooming.

[0002]

2. Description of the Related Art In order to perform focusing, zooming, or the like in an endoscope, it is necessary to move an objective optical system portion built in the distal end of an insertion portion in an axial direction by remote control.

Conventionally, therefore, an objective frame having an objective optical system attached thereto is slidably fitted in a fixed cylinder, which is fixedly arranged in the distal end of an insertion portion, in the axial direction, and is moved in the axial direction by remote control. Focusing or zooming is performed by connecting the distal end of the operation wire to the object frame and sliding the object frame in the axial direction via the operation wire.

[0004]

Since the insertion portion of the endoscope is elongated and has various built-in components inserted therein, remote control such as focusing and zooming must be performed via operation wires.

However, as described above, when the distal end of the operation wire is directly connected to the objective frame and the operation wire is moved forward and backward, the pulling force of the operation wire directly acts on the objective frame, so that the objective frame is loosened from the fixed cylinder. There has been a problem that the observation image is partially out of focus when tilted by an amount.

[0006] Therefore, the present invention provides a good endoscope observation without focusing and zooming by moving the objective frame in the axial direction without tilting by remote control via an operation wire, and performing defocusing in the entire adjustment range. It is an object of the present invention to provide an endoscope objective driving mechanism capable of obtaining an image.

[0007]

In order to achieve the above object, an objective driving mechanism for an endoscope according to the present invention comprises a distal end of an operation wire which is moved in an axial direction by remote control and is connected to a distal end of an insertion portion. And a slide cylinder slidably disposed in the axial direction, and at least one of an objective frame to which the objective optical system is mounted and an image receiving portion frame to which the image receiving portion of the image transmitting means is mounted are slidably fitted in the axial direction. And a fixed cylinder fixedly arranged in the distal end of the insertion portion, and fitted and arranged on the fixed cylinder so as to be rotatable about an axis, and driven to rotate about the axis by a sliding operation of the slide cylinder. By means of the objective frame and the image receiving portion frame, a cam tube that axially drives a frame slidably fitted in the fixed tube, and the cam frame that drives the objective frame and the image receiving portion frame inside the fixed tube. Slide yourself A first urging means for urging the frame inserted in the shaft in the axial direction, and a second urging means for urging the slide cylinder forward with an urging force which is always larger than the urging force of the first urging means. And a biasing means.

[0008] A pin is protruded from each of the slide frame and the objective frame and the image receiving portion frame, the frame being slidably fitted in the fixed cylinder and the cam cylinder. A plurality of cam grooves with which each pin separately engages may be formed in the cam cylinder.

Further, a frictional resistance applying means for applying a frictional resistance to the axial movement of the operating wire is provided, and the frictional resistance is larger than the maximum urging force of the second urging means. It is good to make it larger.

[0010] Both the objective frame and the image receiving portion frame are slidably fitted in the fixed cylinder, and the first biasing means is provided between the objective frame and the image receiving portion frame. It may be arranged compressed.

[0011] One or both of focusing and zooming may be performed by moving at least one of the objective frame and the image receiving unit frame.

[0012]

Embodiments of the present invention will be described with reference to the drawings. FIG. 2 shows the entire configuration of the endoscope,
The operating portion 2 is connected to the base end of the flexible tubular insertion portion 1, and the bending portion 4 formed at the distal end portion of the insertion portion 1 is operated by rotating a bending operation knob 3 provided on the operation portion 2. ,
It can be bent in any direction and at any angle.

A distal end body 10 containing an objective optical system and the like is connected to the distal end of the bending section 4. In the vicinity of the connection between the insertion section 1 and the operation section 2, a treatment instrument insertion port 5 which is an entrance of a treatment instrument insertion channel inserted and arranged in the insertion section 1 is protrudingly arranged. Reference numeral 6 denotes an optical system operation lever for performing a focusing operation or a zooming operation.

A connector 8 is connected to a distal end of a flexible connecting tube 7 connected to a rear portion of the operation unit 2. The connector 8 supplies illumination light to a light guide fiber bundle for illumination, which will be described later, and a distal end. It is connected to a light source device and a video processor (not shown) for processing video signals picked up by a solid-state image pickup device built in the main body 10.

FIG. 3 is a front view of the distal end body 10, and FIG.
1 is an observation window for taking in an observation image, 12 is an illumination window for emitting illumination light for illuminating a subject, 13 is an outlet of a treatment instrument insertion channel, and 14 and 15 are an air supply nozzle and a water supply nozzle. .

FIG. 4 is a side sectional view of the distal end portion of the insertion portion 1 in a section passing through each center line of the observation window 11 and the illumination window 12, and FIG. 5 is a VV sectional view thereof. It is the bending part and the tip part main body described above.

A concave lens 17 for widening the light distribution angle of the illumination light is fitted into the illumination window 12, and an emission end of a light guide fiber bundle 18 is disposed inside the concave lens. A cover lens 20, which is a first lens of the objective optical system, is fitted into the observation window 11, and an objective lens group 21, a solid-state imaging device 24, and the like are arranged inside the cover lens 20. 2
2 is a YAG laser cut filter, and 23 is a cover glass.

The skeleton of the curved portion 4 is constituted by connecting a plurality of node rings rotatably with rivets, and the foremost node ring 4a is covered on the outer peripheral surface of the rear end of the distal end main body 10. It is fitted and connected and fixed by the fixing screw 4b.

4c is a screw piece arranged in a recess formed in the distal end body 10 for screwing the fixing screw 4b, 4d is a bending operation wire, 4e is an elastic rubber outer tube. is there.

FIG. 1 is an enlarged view showing the configuration around the objective optical systems 20 and 21 and the solid-state image sensor 24 in a normal observation state, and FIGS. 6 and 8 show a VI-VI section and a VIII-VIII section. ing.

A fixed inner cylinder 28 is inserted into a fixed outer cylinder 27 fitted and fixed in a hole formed in the tip end body 10 in the axial direction.
As shown in FIG. 6, the (fixed cylinder) is directly fitted and fixed with the fixing screw 29 on the rear side, and the two are fixed on the front side.
A space ring 30 is interposed and fixed between 7, 28,
A constant gap is secured between the two members 27 and 28 over the entire length excluding both end portions.

The cover lens 20 is fixed to the distal end of the fixed inner cylinder 28 in a watertight manner, and a front lid 31 is joined to the space ring 30 so as to close the space between the side surface of the cover lens 20 and the distal end body 10. ing.

A gap between the front lid 31 and the side surface of the cover lens 20 is filled with a defoamed epoxy adhesive, and a fitting surface between the front lid 31 and the tip body 10 is used for sealing. An O-ring 32 is mounted.

In the fixed inner cylinder 28, an objective frame 34 on which the objective lens group 21 is mounted, and an image receiving section frame 35 on which the solid-state imaging device 24 for capturing an observation image is mounted.
They are inserted so as to be able to advance and retreat in the axial direction independently of each other.
33 is an O-ring.

The objective lens group 21 is assembled in a lens barrel 36 and fixed by caulking. The lens barrel 36 is joined to the objective frame 34. However, the lens barrel 36 may be fixed to the objective frame 34 with screws.

Reference numeral 37 denotes a light shielding mask for cutting unnecessary ambient light. The aperture stop is arranged on the front end face of the objective lens group 21. Between the objective frame 34 and the image receiving section frame 35, a first compression coil spring 47 for urging the both in a direction away from them is interposed to prevent rattling.

The solid-state imaging device 24 is fixed to the tip of a flexible substrate 44 such as a TAB (tape automating bonding) substrate, and the cover glass 23 is joined to the front end surface of the solid-state imaging device 24, and The laser cut filter 22 is joined to the front end face of the cover glass 23.

In the flexible substrate 44, the solid-state image sensor 24
A buffer board 43 on which electronic components constituting a driving circuit and the like are mounted is arranged, and a signal cable 4
5 has been pulled out.

An electrically insulating thin insulating tape 38 is continuously wound around the outer peripheral surfaces of the cover glass 23, the solid-state imaging device 24, and the flexible substrate 44 to form a shield tube made of a conductive tube. 40 is fitted on the outside. The shield line of the signal cable 45 is connected to the shield tube 40.

The tip of the shield tube 40 is connected to the solid-state image sensor 24.
The outer surface of the insulating tape 38 is filled with a defoamed electrically insulating epoxy-based adhesive 41 from the middle of the side surface to the tip of the cover glass 23.

Then, an insulating tape 39 is continuously wound from the portion to the outer periphery of the shield tube 40, so that electrical insulation between the shield tube 40 and the image receiving unit frame 35 is ensured. Reference numeral 46 denotes a silicon-based adhesive filled on the rear end side to prevent dust from entering the image receiving unit frame 35.

The shield tube 40 in which the solid-state image pickup device 24 and the electronic circuit are accommodated in this manner is pressed and fixed by the fixing screws 42 screwed into the image receiving portion frame 35. The fixing screw 42 is temporarily loosened when performing focus adjustment in the normal observation state, and is further switched to a close-up magnification observation state, which will be described later, to check the focus. Fix to 35.

However, since the insulating tape 39 is interposed between the distal end surface of the fixing screw 42 and the outer peripheral surface of the shield cylinder 40, the electric insulation between the image receiving portion frame 35 and the shield cylinder 40 is improved. Is secured.

A cylindrical cam cylinder 50 having first, second and third cam grooves 51, 52, 53 formed on the outer peripheral surface of the fixed inner cylinder 28 is rotatably fitted around an axis. And
A slide tube 55 driven by the operation wire 25 and slid in the axial direction is disposed at a position surrounding the cam tube 50.

The distal end of the operation wire 25 is passed through a hole formed in the slide cylinder 55, and the retaining ring 5
7 is fixed. The slide cylinder 55 is slid to the right in FIG. 1 by an operation of operating the optical system operation lever 6 to pull the operation wire 25 from the operation section 2 side.

Then, the operation wire 25 is turned in the opposite direction (that is,
1) by the urging force of the second compression coil spring 58 disposed around the outer periphery of the fixed inner cylinder 28 when the cylinder is moved forward.
, The slide cylinder 55 is slid to the left.

In the normal observation state shown in FIG. 1, the first compression coil spring 47 is most compressed and has the largest urging force, while the second compression coil spring 58 is most extended and has the greatest urging force. Is minimized, but in this state, the urging force F2 of the second compression coil spring 58
Is set to be larger than the urging force F1 of the compression coil spring 47.

Therefore, in any state,
The urging force F2 of the second compression coil spring 58 is larger than the urging force F1 of the first compression coil spring 47,
Of the cam cylinder 50 by the urging force F1 of the compression coil spring 47 of FIG.
Does not rotate on its own.

Reference numerals 62 and 63 are guide tubes having a double structure for guiding the operation wire 25 in the insertion portion 1, the inside being a flexible tube 62 and the outside being a tightly wound coil pipe 63 having a rectangular cross section. , And is adhesively fixed to a connection pipe 61 soldered and fixed to the fixed outer cylinder 27. The flexible tube 62 has a function of preventing the lubricant applied to various built-in components in the insertion section 1 from entering.

A first pin 65 whose front end is movably engaged with the first cam groove 51 formed in the cam cylinder 50 without play is screwed into the slide cylinder 55 so as to protrude inward. Fixed.

A second pin 66 whose head engages with the second cam groove 52 is screwed and fixed to the objective frame 34 so as to protrude outward. The third pin 67 whose head engages with the third cam groove 53 is screwed and fixed so as to protrude outward.

The fixed inner cylinder 28 has a second pin 66
And straight grooves 68 and 69 through which the third pin 67 passes are formed in a direction parallel to the axis. Further, since the second pin 66 and the third pin 67 have their heads engaged with the second cam groove 52 and the third cam groove 53, as shown in FIG. Slotting groove 66 for engaging the tip
a, 67a are formed by half-moon-shaped depressions that are not exposed on the side surfaces.

FIG. 7 shows the first to third cam grooves 51 and 5.
FIG. 5 is a developed view showing an engaged state of the first and third pins 65, 66, 67 with the pins 65, 66, 67;
Is in the position of the normal observation state shown in FIGS.

Here, the second pin 66 for driving the objective lens group 21 is driven by the urging force of the first compression coil spring 47.
Is urged forward to be pressed against the front side wall surface, which is the reference surface of the second cam groove 52, and the third
The pin 67 is driven rearward and pressed against a rear wall surface which is a reference surface of the third cam groove 53.

The angle θ formed by the first cam groove 51 with respect to the axial direction (that is, the optical axis direction) of the cam barrel 50 is in the range of 10 ° to 45 ° in order to perform a smooth operation with a small operation force. Is desirable. In this embodiment, θ ≒ 30 °
Is set to

When the operation wire 25 is pulled by operating the optical system operation lever 6 of the operation section 2 from the normal observation state, the slide cylinder 55 resists the urging force of the second coil spring 58 as shown in FIG. And back (right side in FIG. 10)
The cam cylinder 50 is driven to rotate about the axis by the engagement between the first pin 65 and the first cam groove 51 that slides along with the first pin 65. Its rotation angle is at most 90 °.

When the cam cylinder 50 rotates around the axis, the second and third pins 66 and 67 that engage with the second and third cam grooves 52 and 53 formed in the cam cylinder 50 move in the axial direction. The object frame 34 is moved forward (to the left in FIG. 10).
And the image receiving unit frame 35 slides rearward (to the right in FIG. 10).

The length of the first cam groove 51 is equal to the length of the cam cylinder 5.
The rotation angle of 0 is exactly 90 °, but the second and third
The cam grooves 52 and 53 are formed such that both end portions when the cam cylinder 50 is rotated by 90 ° are longer than the first cam grooves 51. As a result, the first cam groove 51 and the first pin 65 engaged with the first cam groove 51 serve as a stopper for restricting the rotation angle of the cam cylinder 50.

FIG. 11 shows the engaged state of the first to third pins 65, 66, 67 with the first to third cam grooves 51, 52, 53 when the cam cylinder 50 is rotated by 90 °. FIG. 12 is a development view, and FIG. 12 shows a XII-XII cross section.

In the state shown in FIGS. 10 to 12, the objective lens group 21 moves forward without moving the cover lens 20, and the solid-state imaging device 24 moves backward.

As a result, zooming is performed. For example, during normal observation, the viewing angle is 120 ° and the observation distance is 5 to 10
What was in the range of 0 mm, the viewing angle becomes 40 ° and the observation distance becomes in the range of 2 to 4 mm.

When the optical system operation lever 6 is stopped at an arbitrary intermediate position, the objective frame 34 and the image receiving portion frame 35 driven via the operation wire 25 and the slide cylinder 55 stop at an intermediate position in the movement range. Thus, observation can be performed at an arbitrary magnification between the normal observation state and the close-up magnification observation state.

FIG. 13 shows a mechanism for converting the rotational movement of the optical system operation lever 6 provided on the operation section 2 into the linear movement of the operation wire 25. It is connected and fixed to a drum 71 rotatably supported by a frame 70 in the section 2.

An end of an arcuate link 72 along the outer peripheral surface is rotatably attached to the drum 71, and a linear link 73 is connected to the other end of the arcuate link 72 via a stroke adjusting screw 74. Are linked.

The cylinder body 76 fixed to the frame 70 by screws or the like (not shown)
A piston body 77 to which the base end of the operation wire 25 is adhesively fixed and the base end of the operation wire 25 is connected and fixed by soldering is inserted into the cylinder body 76 so as to be able to advance and retreat in the axial direction.

A linear link 73 is connected and fixed to the protruding end of the piston body 77 by screwing. An O-ring 79 is mounted on the outer peripheral portion of the piston body 77 located in the cylinder body 76 in a state of being crushed by being pressed by the inner peripheral surface of the cylinder body 76.
And a cylinder body 76 is provided with a frictional resistance F3.

The frictional resistance F3 is set to be larger than the maximum urging force F2 _MAX of the second compression coil spring 58 for urging the operation wire 25 in the distal end body 10 in the distal direction.

Therefore, when the optical system operation lever 6 is stopped at an arbitrary position, the operation wire 25 is stopped by the frictional resistance F3 of the O-ring 79, and the second compression coil spring 58
Does not move by the urging force F2.

The present invention is not limited to the above embodiment. For example, only focusing may be performed, or both focusing and zooming may be performed. Also, the object lens group 21 and the solid-state imaging device 24 are moved by pulling the operation wire 25.
Either one may be used.

[0060]

According to the present invention, when the operating wire is pulled by remote control, the cam barrel is driven to rotate around the axis by the slide barrel that slides in the axial direction, whereby one or both of the objective frame and the image receiving unit frame are driven. Is driven in the axial direction to perform focusing and zooming, so that focusing and zooming can be performed in good focus without tilting the objective frame, and a clear observation image can be obtained. Since the urging force of the second urging means for urging the slide cylinder to the front side is always larger than the urging force of the first urging means for urging the inserted frame in the axial direction, Focusing and zooming operations in accordance with the intention of the present invention can be obtained.

Further, by applying a frictional resistance larger than the maximum urging force of the second urging means to the operation wire, an observation image at an arbitrary position during the focusing or zooming operation can be stably obtained. .

[Brief description of the drawings]

FIG. 1 is an enlarged side sectional view of an objective optical system portion in a normal observation state according to an embodiment of the present invention.

FIG. 2 is a side view showing the entire configuration of the endoscope according to the embodiment of the present invention.

FIG. 3 is a front view of a distal end of an insertion portion of the endoscope according to the embodiment of the present invention.

FIG. 4 is a side sectional view of a distal end of an insertion portion of the endoscope according to the embodiment of the present invention.

FIG. 5 is a sectional view taken along line VV in FIG. 4 of the embodiment of the present invention.

FIG. 6 is a sectional view taken along the line VI-VI in FIG. 1 of the embodiment of the present invention;

FIG. 7 is a development view showing an engagement state between the cam groove and the pin in a normal observation state according to the embodiment of the present invention.

FIG. 8 is VIII-VIII in FIG. 1 of the embodiment of the present invention.
It is sectional drawing.

FIG. 9 is a perspective view of a pin according to the embodiment of the present invention.

FIG. 10 is an enlarged side sectional view of an objective optical system portion in a close-up magnification observation state according to the embodiment of the present invention.

FIG. 11 is a development view showing an engagement state between the cam groove and the pin in the close-up observation state according to the embodiment of the present invention.

FIG. 12 shows XII-X in FIG. 10 of the embodiment of the present invention.
It is II sectional drawing.

FIG. 13 is a cross-sectional view of a mechanism for converting a rotational movement of the optical system operation lever into a linear movement of the operation wire according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insertion part 6 Optical system operation lever 21 Objective lens group 24 Solid-state image sensor 25 Operation wire 28 Fixed inner cylinder (fixed cylinder) 34 Objective frame 35 Image receiving part frame 47 First compression coil spring 50 Cam cylinder 51, 52, 53 Cam groove 55 Slide cylinder 58 Second compression coil spring 65, 66, 67 Pin 76 Cylinder body 77 Piston body 79 O-ring (friction resistance applying means)

Claims (5)

[Claims] 1. A slide tube connected to the distal end of an operation wire that moves in the axial direction by remote control and slidably disposed in the distal end of an insertion portion in the axial direction, and an objective frame to which an objective optical system is attached. At least one of the image receiving unit frames to which the image receiving unit of the image transmitting unit is attached is slidably fitted in the axial direction, and is fixedly disposed in the distal end of the insertion portion. The object cylinder and the image receiving portion frame are slidably fitted into the fixed cylinder by being arranged to be fitted to the fixed cylinder and being rotated around the axis by the sliding operation of the slide cylinder. A cam cylinder for driving the frame in the axial direction; a first urging means for axially urging a frame slidably fitted in the fixed cylinder among the objective frame and the image receiving unit frame; The first urging means And a second urging means for urging the slide cylinder forward with an urging force that is always greater than the urging force of the endoscope. 2. A pin protruding from each of the objective frame and the image receiving portion frame slidably fitted in the fixed cylinder and the slide cylinder to the cam cylinder, and 2. The objective drive mechanism for an endoscope according to claim 1, wherein a plurality of cam grooves in which the respective pins are separately engaged are formed in the cam cylinder. 3. A friction resistance applying means for applying frictional resistance to the axial movement of the operating wire, the frictional resistance being greater than the maximum urging force of the second urging means. The objective drive mechanism for an endoscope according to claim 1 or 2, which is large. 4. The apparatus according to claim 1, wherein both the objective frame and the image receiving portion frame are slidably fitted in the fixed cylinder, and the first urging means is provided between the objective frame and the image receiving portion frame. The objective drive mechanism for an endoscope according to claim 1, 2 or 3, wherein the objective drive mechanism is arranged in a compressed state. 5. The objective drive mechanism for an endoscope according to claim 1, wherein at least one of focusing and zooming is performed by moving at least one of the objective frame and the image receiving unit frame. .