JP3665439B2 - Electronic endoscope - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic endoscope in which an endoscopic observation image is picked up by a solid-state imaging device arranged at the tip of an insertion portion.
[0002]
[Prior art]
In an electronic endoscope, generally, an objective optical system and a solid-state imaging device for capturing an image formed by the objective optical system are arranged in a distal end portion main body constituting the distal end of the insertion portion. . A CCD (charge coupled device) is widely used as a solid-state imaging device.
[0003]
[Problems to be solved by the invention]
Endoscopes need to be cleaned and disinfected each time they are used to prevent infection. As disinfection methods, chemical disinfection and ethylene oxide gas sterilization have been widely performed so far.
[0004]
However, if disinfectant solution or ethylene oxide gas remains in the endoscope, it may be harmful to the human body or to sterilize Helicobacter pylori and other viruses that cause gastric ulcers at a higher level. High-pressure steam sterilization (autoclave) has been performed.
[0005]
Autoclaves are non-toxic and safe for the human body, but generally, an object to be sterilized is placed in a high temperature environment of about 120 ° C to 135 ° C.
However, in general, a CCD is often damaged when heated to about 80 ° C. or more due to a difference in thermal expansion coefficient between an adhesive used for assembly and an adherend. For this reason, it has been difficult to sterilize electronic endoscopes using an autoclave.
[0006]
In addition, since the pitch between pixels of the CCD is as small as about 6 to 10 μm, if the discharge occurs in the CCD due to static electricity generated while assembling the endoscope, it causes electrostatic breakdown and becomes a defective product. It may become. In such a case, all endoscopes must be disassembled and reassembled from the beginning.
[0007]
Further, when the endoscope is being used, the tip of the insertion portion may be hit or dropped on the floor, and the impact may damage the CCD. In such a case, it is necessary to replace the entire endoscope or to disassemble and repair the entire endoscope in order to replace the CCD.
[0008]
The present invention has been made to improve the above-described disadvantages, and is an electronic device that can easily replace only the solid-state imaging element portion at the tip and can be sterilized by an autoclave. An object is to provide an endoscope.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, an electronic endoscope according to the present invention is an electronic device in which an objective optical system and a solid-state imaging device for imaging an image formed by the objective optical system are provided at the distal end of the insertion portion. In the endoscope, a unit to which the objective optical system and the solid-state imaging device are attached is configured to be detachable from the outside at the distal end portion of the insertion portion, and the unit is attached to the distal end portion of the insertion portion. The electrical contact connected to transmit an imaging signal or the like between the distal end portion of the insertion portion and the unit when in a state, the rear end surface of the unit and the distal end surface of the distal end portion of the insertion portion that contacts the electrical contact point It is provided in and.
[0010]
The unit may be attached to and detached from the front end portion of the insertion portion, and a plurality of the electrical contacts may be provided on the unit and the front end portion of the insertion portion.
[0011]
The electrical contacts may be arranged to face the unit in a direction parallel to the axial direction, one of the electrical contacts on the unit side and the electrical contact on the insertion portion side being a pin shape, May have a cylindrical shape into which the pin-shaped electrical contacts are inserted.
[0012]
Further, biasing means for biasing the unit-side electrical contact and the insertion portion-side electrical contact in a direction in contact with each other may be provided on at least one of the unit side and the insertion portion side. .
[0013]
Further, it is preferable that waterproof means is provided to prevent external moisture from entering at least the electrical contact portion when the unit is attached to the distal end portion of the insertion portion.
[0014]
In addition, when the unit is removed from the distal end portion of the insertion portion, the distal end portion of the insertion portion may be waterproof so that external moisture does not enter the distal end portion of the insertion portion. . And it is good for the said unit itself to have a waterproof structure in which external moisture does not enter the inside.
[0015]
Further, a fixing member for fixing the unit to the distal end portion of the insertion portion is screwed to the distal end portion of the insertion portion when the unit is attached to the distal end portion of the insertion portion. It may be.
[0016]
Alternatively, the fixing member for fixing the unit to the distal end portion of the insertion portion is click-fixed to the distal end portion of the insertion portion when the unit is attached to the distal end portion of the insertion portion. It may be like this.
[0017]
The fixing member may be a hood-like member that is detachable with respect to the distal end portion of the insertion portion.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 2 shows an electronic endoscope. A proximal end of an insertion portion 1 made of a flexible tube is connected to an operation portion 2, and a distal end unit 3 is detachably connected to a distal end portion 1 a of the insertion portion 1. ing. Reference numeral 4 denotes a bending portion that can be bent by remote operation from the operation portion 2.
[0019]
FIG. 1 shows a distal end portion 1a of the insertion portion 1, and 6 is attached to the distal end of a flexible tube (including the bending portion 4), and the distal end unit 3 is detachably connected to the front side thereof. It is a tip cap.
[0020]
The unit main body 7 constituting the block of the tip unit 3 is made of, for example, electrically insulating plastic, and an observation window 8 and an illumination window 9 are arranged on the tip surface.
[0021]
An objective optical system 11 is built inside the observation window 8 of the unit main body 7, and an imaging surface of a solid-state imaging device 12 made of, for example, a CCD is disposed on the imaging surface of a subject by the objective optical system 11. Yes.
[0022]
Reference numeral 13 denotes a circuit board to which the solid-state image sensor 12 is attached. In addition to the solid-state image sensor 12, an electronic component 14 for driving the solid-state image sensor 12 is attached.
[0023]
A short light guide fiber 16 for transmitting illumination light for illuminating the subject is disposed inside the illumination window 9, and a cover glass 17 is fitted into the illumination window 9.
[0024]
The unit main body 7 is formed in a columnar shape and is detachable from the front end base 6 of the insertion portion 1 from the front. A recess 20 formed on the front end face of the front end base 6 is formed on the rear end face of the unit main body 7. A projecting portion 19 that fits in is projected, and functions as positioning and rotation prevention.
[0025]
The periphery of the unit main body 7 is surrounded by a cylindrical hood-like member 21, and the rear end face of the unit main body 7 is formed by screwing a screw portion 22 formed between the hood-like member 21 and the front end cap 6. Is pressed against the front end surface of the front end cap 6 from the front (left side in FIG. 1) and fixed in contact therewith.
[0026]
A plurality of pin-shaped electrical contacts 24 connected to the circuit on the circuit board 13 via connection wires 23 protrude rearward and parallel to the axial direction of the unit body 7 on the rear end surface portion of the unit body 7. It is installed.
[0027]
On the other hand, a plurality of cylindrical electrical contacts 25 connected to the internal electrical wiring 26 are arranged on the distal end surface portion of the distal end cap 6 so as to face the electrical contacts 24 on the unit body 7 side and to be parallel to the axial direction. Has been. Reference numeral 27 denotes an electrical insulating member.
[0028]
As a result, as shown in FIG. 1, when the tip unit 3 is connected to the tip portion 1 a of the insertion portion 1, the electrical contact 24 on the unit body 7 side is connected to the cylindrical electrical contact 25 on the tip base 6 side. The two electrical contacts 24 and 25 are press-fitted, and signals (imaging signal, CCD drive signal, etc.) are transmitted between the solid-state imaging device 12 and the electrical wiring 26 in the insertion portion 1.
[0029]
When connecting the tip unit 3 to the tip cap 6, the hood-like member 21 is first shifted to the front side of the unit body 7 by about half of its length compared to the state shown in FIG. Then, the rear end portion of the unit body 7 is connected to the front end portion of the front end cap 6. At that time, the positioning between the unit main body 7 and the tip cap 6 is performed by the engagement of the convex portion 19 and the concave portion 20 and the connection of the electrical contacts 24 and 25.
[0030]
Then, the hood-like member 21 is shifted backward (in a direction approaching the tip cap 6) from the state, and the hood-like member 21 and the tip cap 6 are screwed together by the screw portion 22. Since the unit main body 7 and the tip cap 6 are engaged in a relatively non-rotating state, the unit main body 7 does not rotate during the screwing operation.
[0031]
When the hood-like member 21 is tightened so that the screw portion 22 is screwed, the flange portion 7 a protruding from the rear end of the outer peripheral portion of the unit body 7 is formed on the inner peripheral surface of the hood-like member 21. The step portion 21 a is pressed and the unit main body 7 is pressed and fixed to the front end face of the tip cap 6.
[0032]
Then, if the screw portion 22 between the hood-like member 21 and the tip cap 6 is released and the unit body 7 is pulled forward with respect to the tip cap 6, the tip unit 3 is detached from the tip cap 6, and the electrical contact 24. , 25 are disconnected.
[0033]
Reference numeral 28 denotes an illumination light guide fiber inserted and arranged in the insertion portion 1, and its emission end face is located on the tip face of the tip cap 6. As shown in FIG. 1, in the state where the tip unit 3 is connected to the tip portion 1 a of the insertion portion 1, the end surfaces of the light guide fibers 16 and 28 in both the tip unit 3 and the insertion portion 1 are tight. It comes to oppose.
[0034]
A sealing O-ring 31 that is in close contact with the outer peripheral surface of the unit main body 7 is attached to the inner peripheral surface near the tip of the hood-like member 21. Further, a sealing O-ring 32 that is in close contact with the inner peripheral surface of the mouth of the hood-like member 21 is attached to the rear end portion of the screw portion 22 of the tip cap 6.
[0035]
As a result, as shown in FIG. 1, in the state where the tip unit 3 is connected to the tip portion 1 a of the insertion portion 1, the electrical contacts 24 and 25 and the screw portion are caused by the sealing effect by both O-rings 31 and 32. 22 and the like prevent external moisture from entering.
[0036]
Therefore, when the distal end unit 3 is attached to the distal end portion 1 a of the insertion portion 1, there is no possibility that moisture adheres to the electrical contacts 24 and 25 and a signal failure or the like occurs. The O-rings 31 and 32 also have a function of preventing the screw part 22 from loosening.
[0037]
The tip unit 3 has a hood-like member 21 that is rotatable and slidable with respect to the unit main body 7 and can be detached from the unit main body 7. However, the surface portion of the unit main body 7 is all sealed watertight. In addition, moisture is prevented from entering the inside from the outside. Therefore, the tip unit 3 can be sufficiently cleaned and disinfected in a single state removed from the insertion portion 1.
[0038]
On the other hand, the insertion portion 1 also has a waterproof structure in which no moisture enters the inside from the outside when the tip unit 3 is removed. Therefore, when this electronic endoscope is used for inspection, the insertion unit 1 side (including the operation unit 2) can be placed in the autoclave device with the distal end unit 3 removed, and sterilization using high-pressure steam can be performed.
[0039]
If the tip unit 3 is thus removed and sterilized and sterilized, the solid-state image sensor 12 does not have to be placed in the autoclave device, and the solid-state image sensor 12 can be protected from thermal destruction.
[0040]
Further, since the tip unit 3 in which the solid-state image pickup device 12 is incorporated is detachable from the insertion portion 1, when the solid-state image pickup device 12 is damaged during assembly or use, only the tip unit 3 is replaced. There is no need to add any hand to the insertion portion 1 side.
[0041]
When a large number of electrical contacts 24 and 25 are required, an appropriate arrangement such as arranging the electrical contacts 24 and 25 on the circumference as shown in FIG. 3 can be taken.
[0042]
FIG. 4 shows a second embodiment of the present invention, in which the light guide fiber 28 on the insertion portion 1 side protrudes straight to the distal end portion of the distal end unit 3, and the light guide base 28 a is attached to the unit body 7. It is inserted through the formed fitting hole 41. Thereby, the distal end unit 3 is positioned with respect to the distal end portion 1 a of the insertion portion 1.
[0043]
The light guide base 28 a is made of, for example, a stainless steel pipe, and is fixed to the tip base 6 in a watertight manner. The electrical contacts 24 and 25 are disposed on the rear end surface of the unit body 7 and the front end surface of the front end cap 6 so as to face each other in parallel to the axial direction.
[0044]
Further, in order to prevent moisture from entering the electrical contacts 24 and 25 from the gap between the fitting hole 41 formed in the unit main body 7 and the light guide base 28a, the inner peripheral portion of the fitting hole 41 is used for sealing. O-ring 42 is attached.
[0045]
As shown in an enlarged view in FIG. 5, the electrical contact 25 on the distal end portion 1 a side of the insertion portion 1 has a concave front surface and is arranged side by side on the distal end surface of the distal end cap 6. And the front wall part 46 of the front-end | tip base 6 is urged | biased by the compression coil spring 45 provided in the cavity 44 formed in the back so that it may swell forward a little.
[0046]
On the other hand, the electrical contact 24 on the unit body 7 side is formed in a convex shape toward the rear, and the electrical contact 25 on the distal end cap 6 side is positioned on the rear end surface of the unit body 7 that abuts on the distal end surface of the distal end cap 6. Are arranged together.
[0047]
Therefore, as shown in FIG. 4, in a state where the tip unit 3 is attached to the tip portion 1 a of the insertion portion 1, both the electrical contacts 24 and 25 are pressed together, and the front wall portion 46 of the tip base 6 is moved. It is elastically deformed so as to return to a straight state, and the urging force of the compression coil spring 45 acts in a direction in which the electrical contacts 24 and 25 are brought into contact with each other.
[0048]
The hood-like member 21 that fixes the distal end unit 3 to the distal end portion 1a of the insertion portion 1 is the same as that in the first embodiment. However, a rubber seal member 47 is lined on the outer peripheral portion of the tip cap 6, and the waterproof effect is enhanced by the mouth end of the hood-like member 21 coming into contact with the seal member 47. Therefore, the O-ring 32 can be omitted.
[0049]
FIG. 6 shows a third embodiment of the present invention, in which a protrusion 54 protruding rearward from the unit body 7 is inserted into a circumferential groove 53 formed on the outer peripheral surface near the front end of the tip cap 6. Are so-called click-coupled.
[0050]
A large number of slits are cut from the rear of the projection 54 so that the projection 54 has springiness. In addition, the protrusion 54 does not need to be formed on the whole circumference, for example, may be partially formed in about three places on the circumference. In that case, the circumferential groove 53 may be partially made in accordance with the protrusion 54.
[0051]
In the state where the tip unit 3 is attached to the tip cap 6, the projection 54 portion of the unit body 7 is pressed from the outside by the hood-like member 21 screwed with the unit body 7 at the screw portion 55, and the unit body 7 Is prevented from coming off the tip cap 6. Other parts are the same as those in the first embodiment, and a description thereof will be omitted.
[0052]
In connecting the tip unit 3 to the tip cap 6 in this embodiment, first, the screw engagement between the unit body 7 and the hood-like member 21 in the screw portion 55 is loosened, and the hood-like member 21 is shifted to the front side. In this state, the protrusion 54 at the rear end portion of the unit body 7 is elastically deformed and engaged with the circumferential groove 53 of the tip cap 6.
[0053]
The positioning at that time is performed by connecting the electrical contacts 24 and 25. However, when the protrusion 54 and the circumferential groove 53 are partially asymmetrically formed in the circumferential direction, positioning by the protrusion 54 and the circumferential groove 53 is also possible.
[0054]
From this state, when the hood-like member 21 is screwed into the unit main body 7 at the screw portion 55, the hood-like member 21 covers the engaging portion of the protrusion 54 with the circumferential groove 53, and the unit main body 7 is attached to the tip cap 6. It will be in a state that cannot be removed
[0055]
FIG. 7 shows a fourth embodiment of the present invention. Contrary to the embodiment shown in FIG. 6, a circumferential groove 53 is formed on the unit body 7 side so as to have a spring property. The protrusion 54 protrudes forward from the tip end side of the tip cap 6. The attachment and detachment of the hood-like member 21 and the expansion of the protrusion 54 are suppressed by the hood-like member 21 are the same as in the third embodiment.
[0056]
【The invention's effect】
According to the present invention, when the unit to which the objective optical system and the solid-state imaging device are attached is configured to be detachable from the front at the distal end portion of the insertion portion, and the unit is attached to the distal end portion of the insertion portion. By providing electrical contacts connected to transmit imaging signals and the like between the distal end portion of the insertion portion and the unit on the rear end surface of the unit and the distal end surface of the distal end portion of the insertion portion that is in contact with the unit, The unit containing the image sensor can be removed from the distal end of the insertion section, and only the solid-state image sensor can be easily replaced. Can be processed.
[Brief description of the drawings]
FIG. 1 is a side sectional view of a distal end portion of an insertion portion of an electronic endoscope according to a first embodiment of the present invention.
FIG. 2 is an overall schematic view of the electronic endoscope according to the first embodiment of the present invention.
FIG. 3 is a schematic diagram showing an example of arrangement of electrical contacts according to the first embodiment of the present invention.
FIG. 4 is a side sectional view of a distal end portion of an insertion portion of an electronic endoscope according to a second embodiment of the present invention.
FIG. 5 is a partial enlarged cross-sectional view of a second embodiment of the present invention.
FIG. 6 is a side sectional view of a distal end portion of an insertion portion of an electronic endoscope according to a third embodiment of the present invention.
FIG. 7 is a partial schematic side sectional view of an electronic endoscope according to a fourth embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Insertion part 1a Tip part 3 Tip unit 6 Tip base 7 Unit main body 12 Solid-state image sensor 21 Hood-like members 24 and 25 Electrical contact

Claims (12)

In an electronic endoscope in which an objective optical system and a solid-state imaging device for capturing an image formed by the objective optical system are provided at the distal end of the insertion portion,
A unit to which the objective optical system and the solid-state image sensor are attached is configured to be detachable from the front at the distal end portion of the insertion portion, and the unit is attached to the distal end portion of the insertion portion. Rutotomoni provided an electrical contact which is connected to transmit an image signal or the like between the tip portion and the unit of the insertion portion, to the front end surface of the rear end surface and the tip portion of the insertion portion in contact with the that of the unit ,
A light guide for illumination is projected straight forward from the distal end surface of the distal end portion of the insertion portion and is inserted into a fitting hole formed in the unit, thereby positioning the unit with respect to the distal end portion of the insertion portion. An electronic endoscope characterized in that is performed . The electronic endoscope according to claim 1, wherein the unit is attached to and detached from a distal end portion of the insertion portion from the front. The electronic endoscope according to claim 1, wherein a plurality of the electrical contacts are provided on each of the unit and the distal end portion of the insertion portion. 4. The electronic endoscope according to claim 1, wherein each of the electrical contacts is disposed so as to face the unit in a direction parallel to the axial direction. 5. The electronic endoscope according to claim 4, wherein one of the electrical contact on the unit side and the electrical contact on the insertion portion side has a pin shape, and the other has a cylindrical shape into which the pin-shaped electrical contact is inserted. The urging means for urging the electric contact on the unit side and the electric contact on the insertion portion side in a direction to contact the electric contact on the unit side is provided on at least one of the unit side and the insertion portion side. The electronic endoscope according to 2, 3, 4 or 5. 7. A waterproof means for preventing external moisture from entering at least the electric contact portion when the unit is attached to the distal end portion of the insertion portion is provided. Electronic endoscope according to item. The distal end portion of the insertion portion has a waterproof structure so that external moisture does not enter the distal end portion of the insertion portion when the unit is detached from the distal end portion of the insertion portion. 8. The electronic endoscope according to any one of items 7. 9. The electronic endoscope according to claim 1, wherein the unit itself has a waterproof structure that prevents external moisture from entering the inside. When the unit is attached to the distal end portion of the insertion portion, a fixing member for fixing the unit to the distal end portion of the insertion portion is screwed into the distal end portion of the insertion portion. The electronic endoscope according to any one of claims 1 to 9. A fixing member for fixing the unit to the distal end portion of the insertion portion when the unit is attached to the distal end portion of the insertion portion is click-fixed to the distal end portion of the insertion portion. The electronic endoscope according to any one of claims 1 to 9. The electronic endoscope according to claim 10 or 11, wherein the fixing member is a hood-like member that is detachable with respect to a distal end portion of the insertion portion.

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