JPH10229971A - Electronic endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic endoscope capable of easily replacing only the solid camera element at the head and of processing the sterilization via an autoclave. SOLUTION: This endoscope is provided at the insertion head tip with an objective optical system 1 and a solid camera element 12 for photo-taking an image to be imaged via the objective optical system 11. A unit 3, both the objective optical system 11 and the solid camera element 12 are attached thereto, is made in a free fashion of attaching-to/detaching-from externally. The unit 3 is fitted to the insertion head tip 1a via a bayonet mechanism 60.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic endoscope in which an endoscope observation image is captured by a solid-state imaging device disposed at a distal end of an insertion section.

[0002]

2. Description of the Related Art Generally, in an electronic endoscope, an objective optical system and a solid-state imaging device for picking up an image formed by the objective optical system are provided inside a distal end main body constituting a distal end of an insertion section. Are located in As a solid-state imaging device, C
CDs (Charge Coupled Devices) are widely used.

[0003]

The endoscope must be cleaned and disinfected after each use to prevent infection. As the disinfection method, chemical solution disinfection and ethylene oxide gas sterilization have been widely performed so far.

However, if an antiseptic solution or ethylene oxide gas remains in the endoscope, it may be harmful to the human body, and sterilize Helicobacter pylori and other viruses that cause stomach ulcer to a higher level. For this purpose, high-pressure steam sterilization (autoclave) has been performed.

[0005] Autoclaves are non-toxic and safe for the human body.
It will be placed in a high temperature environment of about 5 ° C. However, the CCD is often damaged when heated to about 80 ° C. or more due to a difference in the coefficient of thermal expansion between the adhesive used for assembly and the adherend. Therefore, it has been difficult to sterilize the electronic endoscope with an autoclave.

The CCD has a pitch between pixels of 6-1.
Since it is as small as about 0 μm, static electricity generated while assembling the endoscope may cause electrostatic breakdown when a discharge occurs in the CCD, resulting in a defective product. In such a case, the endoscope must be completely disassembled and reassembled from the beginning.

In addition, the CCD may be damaged by the impact of the end portion of the insertion portion when the end portion is hit or dropped on the floor during use of the endoscope. 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.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned inconvenience, and it is possible to easily replace only the solid-state image pickup device at the tip and to perform sterilization by an autoclave. It is an object of the present invention to provide an electronic endoscope capable of performing the following.

[0009]

In order to achieve the above object, an electronic endoscope according to the present invention comprises an objective optical system and a solid-state image sensor for imaging an image formed by the objective optical system. In an electronic endoscope provided at a distal end of an insertion portion, a unit to which the objective optical system and the solid-state imaging device are mounted is detachably attached to a distal end portion of the insertion portion from outside, and the unit is a bayonet mechanism. Characterized in that it is adapted to be locked to the distal end of the insertion portion.

When the unit is attached to the distal end of the insertion portion, at least an electrical contact connected to transmit an image signal or the like between the distal end of the insertion portion and the unit. Waterproof means for preventing external moisture from entering the portion may be provided.

Further, when the unit to which the objective optical system and the solid-state image pickup device are attached is removed from the distal end of the insertion section, external moisture is prevented from entering the distal end of the insertion section. Preferably, the distal end of the insertion portion has a waterproof structure, and the unit itself has a waterproof structure that prevents external moisture from entering the inside.

A projection protruding forward is provided at the center axis position of the distal end portion of the insertion portion, and a hole through which the projection portion is inserted is formed at the center axis position of the unit. The unit may be able to rotate about the central axis with respect to the distal end portion of the insertion portion when the unit is attached to the distal end portion of the insertion portion. In that case, an illumination light guide may be inserted into the protrusion, and a fluid passage may be formed in the protrusion.

When the unit is locked by the bayonet mechanism at the distal end of the insertion portion, a connection is made between the rear end surface of the unit and the distal end surface of the distal end portion of the insertion portion abutting on the unit. The connected member may be arranged, and the connected member may be a lighting light guide.

Further, a member connected at a fitting portion between the unit and the distal end portion of the insertion portion when the unit is locked at the distal end portion of the insertion portion by the bayonet mechanism is disposed. The connected member may be an electrical contact for transmitting an image signal or the like.

It is preferable that the unit and the distal end of the insertion portion engage in only one location in the bayonet mechanism.

[0016]

Embodiments of the present invention will be described with reference to the drawings. FIG. 2 shows an electronic endoscope, in which a proximal end of an insertion section 1 made of a flexible tube is connected to an operation section 2, and a distal end unit 3 is detachably connected to a distal end portion 1 a of the insertion section 1. ing. Reference numeral 4 denotes a bending portion that can be bent by remote control from the operation portion 2.

FIG. 1 shows a distal end portion 1a of the insertion portion 1. Numeral 6 is attached to the distal end of a flexible tube (including the curved portion 4), and the distal end unit 3 is detachably attached to the distal end thereof. This is the tip base connected to.

The unit body 7 constituting the block of the tip unit 3 is made of, for example, a hard plastic having electrical insulation, and an observation window 8 and an illumination window 9 are arranged on the tip surface thereof.

Inside the observation window 8 of the unit body 7, an objective optical system 11 is built in, and an image pickup surface of a solid-state image pickup device 12 composed of, for example, a CCD is provided on an image forming surface of the object by the objective optical system 11. Are located. Reference numeral 13 denotes a circuit board on which electronic components (not shown) for driving the solid-state imaging device 12 are mounted.

Reference numeral 38 denotes a forceps channel inserted into the insertion section 1, the tip of which is fixed to the tip base 6. In the state shown in FIG. 1 in which the distal end unit 3 is connected to the distal end cap 6, the forceps passage hole 39 formed in the unit main body 7 is connected straight to the forceps channel 38. I have.

The distal end portion of the light guide fiber 28 inserted through the insertion section 1 is inserted and fixed in the light guide base 28a, and the light guide base 28a is
It is loosely inserted into a fitting hole 41 formed through the unit body 7 in the axial direction.

The light guide cap 28a is made of, for example, a stainless steel pipe. The base end of the light guide cap 28a is fixed to the tip cap 6 in a water-tight manner, and the tip end is located at the illumination window 9 on the tip face of the unit body 7. ing.

In order to secure the fixed state between the light guide base 28a and the tip base 6, a flange 28b sandwiching the front end wall of the tip base 6 is provided with a light guide base 28a.
It is projected.

On the outer peripheral surface of the light guide base 28a, an electric contact 25 connected to the electric wiring 26 in the insertion portion 1 via a wiring path formed in the light guide base 28a is provided. An electrical contact 24 connected to the wiring of the circuit board 13 via the connection line 23 is provided on the inner peripheral surface of the fitting hole 41 on the unit body 7 side into which is inserted.

A plurality of electrical contacts 25 on the insertion section 1 side are provided at intervals in the axial direction of the light guide cap 28a, and the electrical contacts 24 on the unit body 7 side are arranged at corresponding positions.

As a result, in a state where the distal end unit 3 is connected to the distal end portion 1a of the insertion portion 1, the two electric contacts 2
4 and 25 are connected, and a signal (an imaging signal, a CCD driving signal, and the like) is transmitted between the solid-state imaging device 12 and the electric wiring 26 in the insertion section 1.

The electric contact 2 is formed through a gap between the fitting hole 41 formed in the unit body 7 and the light guide base 28a.
An O-ring 42 for sealing is mounted on the inner peripheral portion near the distal end of the fitting hole 41 in order to prevent moisture from entering the holes 4 and 25.

The light guide base 28a and the fitting hole 41 are
It is provided at each center axis position of the tip end base 6 and the unit main body 7. Accordingly, the unit main body 7 is rotatable around the light guide base 28a without bias about the central axis.

The tip cap 6 and the unit body 7 are bayonet-coupled by a bayonet mechanism 60 at the time of connection. At the front end of the end cap 6, for example, three bayonet inner claws 61 whose rear cross section (III-III cross section) is shown in FIG. 4, three bayonet outer claws 62 are formed as shown in FIG. 4 when the unit body 7 is viewed from the rear side (right side in FIG. 1).

The inner and outer claws 61 and 62 are formed by the widths (angles) of the claws.
Are different from each other, and there is only one positional relationship where the two claws 61 and 62 are engaged. On the back surface of the outer bayonet claw 62, a groove is formed in which the inner bayonet claw 61 is fitted.

Reference numeral 63 shown in FIG. 4 is a stopper for bringing the inner claw 61 into contact when the bayonet is connected. Also, 51 and 52 shown in FIGS. 3 and 4 are an air supply channel and a water supply channel, and 39 is the above-mentioned forceps passage hole.

When the unit body 7 is connected to the tip base 6, the inner claw 61 of the tip base 6 is inserted between the adjacent outer claws 62 of the unit body 7 (the position is one position). The unit body 7 is rotated with respect to the tip base 6 around the light guide base 28a.

Then, as shown in the front sectional view of FIG. 5, the inner claw 61 enters the back side of the outer claw 62 and overlaps in a predetermined direction, and the unit is positioned at a position where the side surface of the inner claw 61 contacts the stopper 63. The air supply path 51, the water supply path 52, and the forceps passage hole 39 on both the main body 7 side and the end cap 6 side are connected.

In this way, the unit body 7 can be bayonet-coupled by rotating the unit body 7 with respect to the tip base 6 by only about 1/6 rotation, and by rotating the unit body 7 in the opposite direction, the connection can be established. The unit main body 7 can be detached from the tip base 6 by releasing.

As shown in FIG. 1, a rubber sealing member 47 is lined around the outer periphery of the end cap 6 so that the end surface of the unit body 7 contacts the entire circumference when the unit body 7 is connected. Have been.

As a result, when the distal end unit 3 is connected to the distal end portion 1a of the insertion portion 1, the O-ring 42
And the sealing effect of the sealing member 47 prevents external moisture from entering the electrical contacts 24 and 25.

Therefore, when the distal end unit 3 is attached to the distal end portion 1a of the insertion section 1, there is no possibility that moisture adheres to the electrical contacts 24 and 25 to cause a signal failure or the like. Further, the seal member 47 also functions as a locking device when the bayonet mechanism 60 is in the connected state.

The entire surface of the tip unit 3 is sealed in a water-tight manner so that moisture does not enter the inside of the tip unit 3 from outside. Therefore, the tip unit 3
Cleaning and disinfection can be sufficiently performed in a single state removed from the insertion section 1.

On the other hand, the insertion section 1 also has a waterproof structure in which moisture does not enter the interior from the outside when the tip unit 3 is removed. Therefore, when the electronic endoscope is used for inspection, the insertion unit 1 (including the operation unit 2) can be put in an autoclave device and sterilized by high-pressure steam with the tip unit 3 removed.

In this way, if the tip unit 3 is removed and sterilization is performed, the solid-state imaging device 12 does not need to be placed in the autoclave device, so that the solid-state imaging device 12 can be protected from thermal destruction.

Further, since the tip unit 3 in which the solid-state imaging device 12 is incorporated is detachable from the insertion section 1, if the solid-state imaging device 12 is damaged during assembly or use, only the tip unit 3 is damaged. Need not be changed, and there is no need to modify the insertion portion 1 side at all.

The light guide base 2 is located at the center axis position.
Instead of arranging 8a, a pipe forming a fluid passage for air supply, water supply, suction or the like may be arranged so that the unit main body 7 can rotate around the pipe. Alternatively, the inner pawl 61 of the bayonet mechanism 60 may be provided on the unit body 7 side, and the outer pawl 62 may be provided on the tip base 6 side.

FIG. 6 shows a second embodiment of the present invention, in which the rear end portion of the unit main body 7 is fitted to the front end portion of the front end cap 6, and the fitting surface portion is electrically connected. The contacts 24 and 25 are arranged.

The distal end surface of the light guide fiber 28 disposed in the insertion section 1 is located at the distal end surface of the distal end cap 6. Therefore, since the light guide base 28a does not protrude from the front end of the front base 6, the front base 6
It is not necessary to arrange at the position of the axis.

In the unit main body 7, short light guide fibers 16 are independently arranged. When the distal end unit 3 is connected to the distal end portion 1a of the insertion section 1, the end faces of both light guide fibers 28 and 16 are provided. The illumination light is transmitted to face each other. Other configurations including the bayonet mechanism 60 are the same as those of the first embodiment.

FIG. 7 shows a third embodiment of the present invention, in which electric contacts 24 and 25 are arranged on the rear end face of the unit main body 7 and the front end face of the front end cap 6, respectively. The configuration is similar to that of the second embodiment.

In this embodiment, the electrical contacts 25 on the insertion portion 1 side are arranged side by side on the distal end face of the distal end cap 6. The front wall portion 46 of the end cap 6 is urged so as to slightly expand forward by a compression coil spring 45 provided in a cavity 44 formed behind it.

Therefore, in the state shown in FIG. 7 in which the distal end unit 3 is attached to the distal end portion 1a of the insertion section 1, the front wall portion 46 of the distal end cap 6 is elastically deformed so as to return to a straight state. , The biasing force of the compression coil spring 45 acts in the direction in which the electrical contacts 24 and 25 come into contact.

It should be noted that the present invention is not limited to the above-described embodiment, and any type of bayonet mechanism 60 may be used.

[0050]

According to the present invention, the unit including the solid-state image sensor can be detached from the distal end portion of the insertion portion by a slight rotation operation by the bayonet mechanism, and only the solid-state image sensor can be easily replaced. The electronic endoscope can be sterilized by an autoclave without exposing the solid-state imaging device to high heat.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a distal end portion of an insertion section of an electronic endoscope according to a first embodiment of the present invention.

FIG. 2 is an overall schematic diagram of the electronic endoscope according to the first embodiment of the present invention.

FIG. 3 is a rear sectional view of the inner pawl side of the bayonet mechanism according to the first embodiment of the present invention.

FIG. 4 is a rear view of the outer pawl side of the bayonet mechanism according to the first embodiment of the present invention.

FIG. 5 is a rear cross-sectional view of the bayonet mechanism according to the first embodiment of the present invention in a coupled state.

FIG. 6 is a side sectional view of a distal end portion of an insertion section of the electronic endoscope according to the second embodiment of the present invention.

FIG. 7 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.

[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 24, 25 Electrical contact 60 Bayonet mechanism 61 Inner nail 62 Outer nail

Claims (12)

[Claims] 1. An electronic endoscope provided with an objective optical system and a solid-state image pickup device for picking up an image formed by the objective optical system at an end of an insertion section, wherein the objective optical system and the solid-state A unit to which an image pickup device is attached is detachably attached to the distal end portion of the insertion portion from the outside, and the unit is locked to the distal end portion of the insertion portion by a bayonet mechanism. Endoscope. 2. An electrical contact connected for transmitting an image signal or the like between at least the distal end portion of the insertion portion and the unit when the unit is attached to the distal end portion of the insertion portion. 2. The electronic endoscope according to claim 1, wherein waterproof means is provided for preventing external moisture from entering the portion. 3. When the unit to which the objective optical system and the solid-state imaging device are attached is removed from the distal end of the insertion section, external moisture does not enter the distal end of the insertion section. 3. The electronic endoscope according to claim 1, wherein a distal end portion of the insertion portion has a waterproof structure. 4. The electronic endoscope according to claim 1, wherein the unit itself has a waterproof structure that prevents external moisture from entering the inside. 5. A projecting portion projecting forward is provided at a center axis position of a tip portion of the insertion portion, and a hole through which the projecting portion is inserted is formed at a center axis position of the unit. 5. The device according to claim 1, wherein the unit is rotatable about the central axis with respect to the distal end portion of the insertion portion when the unit is attached to the distal end portion of the insertion portion. An electronic endoscope according to the paragraph. 6. An electronic endoscope according to claim 5, wherein an illumination light guide is inserted into said projecting portion. 7. An electronic endoscope according to claim 5, wherein a fluid passage is formed in said projecting portion. 8. A connection is made between a rear end surface of the unit and a front end surface of the distal end portion of the insertion portion which comes into contact with the unit when the unit is engaged with the distal end portion of the insertion portion by the bayonet mechanism. The electronic endoscope according to any one of claims 1 to 7, wherein a member to be formed is disposed. 9. An electronic endoscope according to claim 8, wherein said connected member is a light guide for illumination. 10. A member connected at a fitting portion between the unit and the distal end portion of the insertion portion when the unit is locked by the bayonet mechanism at the distal end portion of the insertion portion. The electronic endoscope according to any one of claims 1 to 7, wherein 11. The electronic endoscope according to claim 8, wherein said member to be connected is an electric contact for transmitting an image signal or the like. 12. The electronic endoscope according to claim 1, wherein the position of the bayonet mechanism in which the unit and the distal end portion of the insertion portion are engaged is only one.