JPH07194518A - Endoscope - Google Patents

Abstract

PURPOSE:To prevent a curving portion from being curved intensely on the side of the control portion of the curving portion during an operation for curving the curving portion by setting the sum of the angles of curvature of adjacent curving pieces to be roughly the same as the difference between each direction of curvature and the angle of curvature of the curving portion, the curving pieces rotating in the same direction as each direction of curvature of the curving portion. CONSTITUTION:The sum of the angles of curvature of adjacent curving pieces 13, 14 that rotate in the same direction as each direction of curvature of a curving portion 4, that is, the angle of curvature of a curving-piece connecting unit 12 before being assembled to an endoscope main body, is set to be roughly the same as the difference between each direction of curvature, that is, the angle of curvature of the curving-piece connecting unit 12 being assembled to the endoscope main body, and the angle of curvature of the curving portion 4. Therefore, during an operation for curving the curving portion, the curving portion is prevented from being curved intensely on the side of the control portion of the curving portion and can be curved gently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope having a bending portion capable of bending in at least two directions.

[0002]

2. Description of the Related Art Generally, it is well known that an endoscope is provided with a bending portion for changing the direction of the distal end portion of an insertion portion. The bending angle of the bending portion varies depending on the purpose of use. For example, in the endoscope for the upper digestive tract, the cardiac, the retrograde view of the duodenal bulb, etc. can be performed, and the UP direction is 180 to 210 ° and the DOWN direction in order to observe the stomach thoroughly and perform various treatments. 90-110 degrees,
In many cases, the LIGHT and LEFT directions are set within an angle range of 100 to 120 °.

Further, a plurality of bending pieces arranged in parallel in the insertion direction of the insertion portion of the endoscope are rotatably connected to the bending portion by rivets. Further, the tip end of the operation wire is fixed to the most advanced bending piece. The other end of the operation wire extends through the insertion portion of the endoscope to the operation portion on the near side, and is connected to a rotating member such as a bending operation knob provided on the operation portion. By pulling the operation wire in accordance with the turning operation of the bending operation knob or the like, each bending piece of the bending portion is turned, and the entire bending portion is bent to a predetermined bending angle.

The bending tube used as each bending piece 1 of the bending portion is formed by processing a pipe material as shown in FIG. Then, the front and rear rivet hole centers 2 and 3 of each bending piece 1 and the axial dimensions A of the shoulder openings 4, 5, 6, and 7,
Many of B, C, and D are commonly used for common use of parts and prevention of wrong assembly.

Therefore, a plurality of bending pieces 1 constituting the bending portion
In the assembled state of the connecting unit of the bending piece 1 integrally connected with each other, that is, in the state before being assembled to the endoscope main body, the bending angle of the connecting unit of the bending piece 1 is the UP direction and the DOWN direction.
Direction, RIGHT direction and LEFT direction are common,
Alternatively, the four directions are common. In this case, the bending angle of the connecting unit of the bending piece 1 before being attached to the endoscope body is made larger than the bending angle in the state of being assembled in the endoscope body. There is 1 between the bending angle of the connecting unit of the bending piece 1 before assembling to the endoscope body and the bending angle of the bending portion after being incorporated in the endoscope body.
Generally, there is a difference of 0 ° or more.

[0006]

Taking the case of bending the bending portion of the endoscope in the UP direction and the DOWN direction in the conventional structure as an example, the connecting unit of the bending piece 1 is an endoscope. When the bending angle in the UP direction is set to 210 ° and the bending angle in the DOWN direction is set to 90 ° in the state of being assembled to the main body, the bending piece 1 of the bending piece 1 before being attached to the endoscope main body is set. The bending angle of the connecting unit, that is, the total bending angle between the adjacent bending pieces 1 and 1 is the UP direction, D
It is set to about 220 to 260 degrees in both OWN directions.

Therefore, when the connecting unit of the bending piece 1 before being attached to the endoscope body is bent in the DOWN direction, the bending angle of the connecting unit of the bending piece 1 and the connection of the bending piece 1 can be increased. The difference between the bending angle at which the connecting unit of the bending piece 1 can be bent and the bending angle when the unit is assembled to the endoscope body is as large as 130 ° to 170 °. In this case, when the bending portion is bent by pulling the operation wire, the bending portion starts to bend from the operation portion side rather than the distal end side with respect to the insertion direction of the insertion portion. It sharply bends at 90 ° at the end position on the side of the part, and is held in a straight line at the part on the tip side of the part, and the part has a shape of sharp bend.

As described above, when the forceps is inserted into the forceps insertion channel in a state where a part of the curved portion is sharply bent locally, the operation becomes heavy at the time of inserting the forceps or the light guide is inserted. There is a problem that the tubes are easily broken or buckled.

Further, when the operating portion side of the bending portion is locally sharply bent, the distal end portion of the insertion portion is farther from the bending portion of the insertion portion than the flexible tube portion on the operating portion side. In a narrow space, for example, the duodenal bulb, there is a problem that the distal end of the insertion portion comes too close to the body wall, making observation and treatment difficult.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an endoscope capable of improving the curved shape of a curved portion and facilitating observation and treatment.

[0011]

According to the present invention, a plurality of bending pieces arranged side by side in the insertion direction of an insertion portion are rotatably connected to each other,
Adjacent to each other, each of which has a bending portion that can bend in at least two directions, and which rotates in the same bending direction of the bending portion as compared to the bending angle of the bending portion in each bending direction when the bending portion is bent. In an endoscope set such that the sum of the bending angles of the bending pieces is large, the sum of the bending angles of the adjacent bending pieces that rotate in the same direction as the bending directions of the bending portions and the bending of the bending portions. Bending angle setting means for setting the difference between the bending angle of the bending portion and the bending angle of the bending portion in substantially the same state is provided.

[0012]

By setting the difference between the sum of the bending angles of the adjacent bending pieces that rotate in the same direction as the bending direction of the bending portion and the bending angle of the bending portion in each bending direction of the bending portion to be substantially the same state. During the bending operation of the bending portion, the bending portion is prevented from being concentrated and bent on the side of the operating portion, so that the bending portion is gently bent.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. FIG. 2 shows a schematic configuration of the entire system of the electronic endoscope 1 incorporating the image pickup device.
Reference numeral 2 is an insertion portion formed of a flexible tube that is inserted into the lumen of the observation target, and 3 is an operation portion connected to the proximal end portion of the insertion portion 2.

Further, 4 is provided on the distal end side of the insertion portion 2 of the endoscope 1.
A bending portion 4 is provided so that it can be bent in any direction. Further, at the tip of the curved portion 4, a tip forming portion 5 incorporating an optical element such as an objective lens is provided.

Further, the operation portion 3 is provided with an operation knob 6 for remotely bending the bending portion 4. Then, by rotating the operation knob 6, the operation wire 7 shown in FIG. 3 is pulled, and the bending portion 4 can be bent through the operation wire 7.

Further, a universal cord 8 has a base end portion connected to the operation portion 3. The tip of the universal cord 8 is connected via a connector 9 to a video processor 10 having a light source device therein. Then, the image pickup signal from the endoscope 1 is transmitted to the video processor 10 via the universal code 8. The video processor 10 has a signal processing circuit for processing an image pickup signal from the endoscope 1, and the processed signal is transmitted to a monitor 11 connected to the video processor 10 to display an image. Thereby, the operator can observe the inside of the lumen of the observation target into which the endoscope 1 is inserted by looking at the display screen of the monitor 11.

Further, FIG. 1A shows a bending piece connecting unit 12 arranged on the bending portion 4 and capable of bending in four directions.
Is shown. This bending piece connecting unit 12 has 2
A plurality of types of bending pieces, that is, a bending piece 13 for bending in two directions shown in FIG. 1B and a bending piece 14 for bending in four directions shown in FIG. 1C are combined in a predetermined order. It is connected.

A wire guide 15 is brazed to the inner peripheral surface of each of the bending pieces 13 and 14. further,
The connecting portions of the bending pieces 13 and 14 are rotatably connected by rivets 16.

Further, a blade 17 is covered on the outer peripheral portion of the bending piece connecting unit 12. This blade 1
Both ends of 7 are bending pieces 1 at the front end of the bending piece connecting unit 12.
8 and the bending piece 19 at the rearmost end are fixed by soldering respectively.

Then, the operation wire 7 is inserted into the wire guide 15, and the operation knob 6 of the operation section 3 is operated to operate the operation wire 7.
It has a structure in which the operation wire 7 is bent in the pulled direction.

The interval between the wire guides 15 brazed to the bending pieces 13 and 14 is A ₁ in the RIGHT / LEFT directions of the bending directions of the bending portion 4.
A ₂ , A ₃ , A ₄ ... And these are in the relationship of the following mathematical expression 1.

[0022]

[Equation 1] The intervals between the wire guides 15 in the UP and DOWN directions are B ₁ , B ₂ , B ₃ , B _4, ...
As in the EFT direction, brazing is performed so that the following relationship of the following equation 2 is established.

[0023]

[Equation 2] In addition, the bending piece connecting unit 1 before being attached to the endoscope body
2 bending angle, that is, the sum of the bending angles of the adjacent bending pieces 13 and 14 that rotate in the same direction as the bending directions of the bending portion 4 and the bending piece connection in the state of being assembled to the endoscope body. The difference from the bending angle of the unit 12 is set to be substantially the same.

For example, when the bending piece connecting unit 12 is assembled to the endoscope main body, the bending angle is 21 in the UP direction.
0 °, DOWN direction 90 °, RIGHT direction / LEF
When the T direction is set to 100 °, the bending angle in the state of being assembled to the endoscope body is increased by the UP.
Direction / DOWN direction 40 °, RIGHT direction / LE
By allowing 20 ° in the FT direction, UP
Direction is 250 °, DOWN direction is 130 °, RIGHT
Direction and LEFT direction are set at 120 °.

At this time, the bending pieces 13 for bidirectional bending are shown in FIG. 1B, and the centers O ₁ and O of the rivet holes 20 and 21 before and after the adjacent bending pieces 13 are rotatably connected to _{each other} . The axial distance between the ₂ and the shoulders 22, 23, 24, 25 is E,
It becomes F, G, H.

The bending piece 14 for bending in four directions is shown in FIG.
In (C), dimensions I, J, K, L related to four directions of UP direction, DOWN direction, RIGHT direction, and LEFT direction.
(Not shown) is set to the same size, and is dimensioned so that it is curved by 120 ° in the RIGHT direction and the LEFT direction.

In this case, the bending angle of the bending piece connecting unit 12 before assembling to the endoscope body in the UP direction and the DOWN direction is 250 ° in the UP direction and 130 ° in the DOWN direction. The dimensions E and G, which are related to the bending, are set to be larger than the dimensions F and H, which are related to the bending in the DOWN direction.

That is, since the bending piece 14 for bending in four directions has already been set to bend by 120 ° in both the UP direction and the DOWN direction,
Each bending piece 13 for bi-directional bending, the front end piece 21, and the rear end piece 22
(250 ° -120 ° = 130 °) is set to bend between and, and (130 ° -1) for the DOWN direction.
The dimensions E, F, G, H of the bending piece 13 for bidirectional bending are set so as to bend (20 ° = 10 °).

As described above, the dimensions of the bending pieces 13 and 14 are set, and the bending portion 4 is bent with the bending piece connecting unit 12 assembled to the endoscope body as shown in FIG.
It shows in (D). Further, for comparison, a state in which the bending portion 4 is bent while the conventional bending piece connecting unit is used is shown by an imaginary line in FIG.

Here, the curved shape in the UP direction is the same in this embodiment and the conventional one. Further, the conventional bending piece connecting unit 1
2 is a state before being attached to the endoscope main body, in the UP direction and DO
Since the WN direction can be bent at the same angle, the bending shape in the DOWN direction is the bending piece connecting unit 12.
Since it is bent only 90 ° when it is assembled to the endoscope body, it sharply bends near the end of the bending portion 4 on the side of the operating portion 4.

On the other hand, in this embodiment, the bending piece connecting unit 12 is DOWN before being assembled to the endoscope body.
Since it is designed to bend only 130 ° in the direction,
As shown in FIG. 1D, the bending portion 4 can be bent with a large and smooth bending radius. Further, the position of the distal end surface of the distal end forming portion 5 in the state of being bent at the maximum bending angle of 90 ° in the DOWN direction is arranged closer to the central axis of the insertion portion 2 than in the conventional case.

Therefore, the insertability of the forceps in the forceps insertion channel is improved, and since the observation can be performed while maintaining the distance between the body wall and the tip surface of the tip forming portion 5, excellent treatment / observation performance is achieved. Can be obtained.

In the above embodiment, the bending angle when the bending piece connecting unit 12 is assembled to the endoscope body is U.
210 ° in P direction, 90 ° in DOWN direction, RIGHT
Although the description has been given by taking the configuration in which the direction and the LEFT direction are set to 100 ° as an example, the present invention is not limited to that angle and can be applied to various angles. Preferably, the difference between the bending angle of the bending piece connecting unit 12 in the state of being assembled to the endoscope body and the bending angle of the bending piece connecting unit 12 before being attached to the endoscope body is 10 ° to. It is good to set it at about 50 °.

Therefore, in the above-mentioned construction, the adjoining members which rotate in the same direction as each bending direction of the bending portion 4, which is the bending angle of the bending piece connecting unit 12 before being assembled to the endoscope body. The difference between the sum of the bending angles of the bending pieces 13 and 14 and the bending angle of the bending portion 4 in each bending direction, which is the bending angle of the bending piece connecting unit 12 when assembled in the endoscope body, Since they are set to be in substantially the same state, when the bending portion 4 is bent, it is possible to prevent the bending portion 4 from being concentrated and bent on the operation portion 3 side.
It can be gently curved. Therefore, it is possible to improve the curved shape of the bending portion 4 and facilitate observation and treatment.

The distance between the wire guides 15 brazed to the bending pieces 13, 14 is A ₁ , A ₂ , A ₃ , A in the RIGHT / LEFT directions of the bending directions of the bending portion 4.
₄ , and the intervals between the wire guides 15 in the UP and DOWN directions are set to be B ₁ , B ₂ , B ₃ , B ₄ ... at substantially equal intervals, so that the operation wire 7 is rubbed with the wire guide 15 by friction. Since the force is applied evenly, compared to the case where the spacing between the wire guides is not nearly the same as in the past,
The operation wire 7 is less likely to be worn or broken, and the durability can be improved.

Further, since the operation wire 7 can be operated smoothly and the frictional force is not locally concentrated, the amount of bending force of the operation knob 6 of the operation portion 3 can be reduced, and a smooth curved shape can be obtained.

In FIG. 3, the brazed position of the conventional wire guide 15 is shown by a broken line. This is because the distance between the wire guides 15 in the UP and DOWN directions is C ₁ , C ₂ , C ₃ , C _4.
However, these are related by the following mathematical expression 3.

[0038]

[Equation 3] Here, in order to bend the bending portion 4, the operation wire 7 is pulled by the operation of the operation knob 6 of the operation portion 3. However, the more the bending, the more the space between the operation wire 7 and the wire guide 15 increases. A large friction force works. Therefore, in the conventional case, the operation wire 7 is worn or broken as compared with the case where the intervals between the wire guides 15 are set to be substantially equal as in the present embodiment, and there is a problem in terms of durability. That is clear.

FIG. 4 shows the tip of the insertion portion 31 of the optical endoscope. Here, 32 is a hard tip forming member made of a metal material or the like in a substantially cylindrical shape. The frontmost bending piece 33 is fixed to the rear side of the tip forming member 32.

The objective lens system 3 is attached to the tip forming member 32.
4 is fixed via a first lens frame 35 and a second lens frame 36. An image guide fiber 37 is arranged on the rear end side of the objective lens system 34.

The second lens frame 36 has a cylindrical body 38.
The front end of the second lens frame 36 is bonded and integrated so that the second lens frame 36 can be easily inserted from the rear end side of the front end constituting member 32. Further, a hole 39 is provided on the rear end side of the cylindrical body 38 so that it can be easily removed. The cylindrical body 38 is fixed by the fixing screw 40 shown in FIG. Further, the fixing screw 40 is filled with a silicone-based elastic adhesive 41.

The front end surface and the outer peripheral surface on the front end side of the tip forming member 32 are covered with a tip insulating cover 42. Further, the outer peripheral surface on the rear end side of the tip forming member 32 is covered with a flexible outer cover 43, and the outer peripheral surface of the front end of the outer cover 43 is fixed to the tip forming member 32 by spooling.

Further, a hole portion 44a of the air / water feeding channel 44 is formed in the tip forming member 32. This hole 4
The front end of the channel pipe 45 of the air / water supply channel 44 is fitted to the rear end side of 4a. Further, the rear end of the channel pipe 45 is projected to the outside of the tip forming member 32, and the front end of the channel tube 44b of the air / water feeding channel 44 is connected to this projection.

Further, the hole portion 44 of the air / water feeding channel 44
The front end portion of a is enlarged in diameter to form a nozzle mounting hole portion 46. A nozzle 48 is attached to the nozzle attachment hole portion 46 via an insulating cylinder 47. Furthermore, the nozzle 4
8, the insulating cylinder 47 is fixed with a fixing screw 49 as shown in FIG. 5, and a silicone-based elastic adhesive 50 having insulating performance is filled on the insulating cylinder 47.

The connecting portion between the channel tube 44b of the air / water feeding channel 44 and the channel pipe 45 is adhered. Further, a thread binding portion 44c, which is thread-tightened from the top of the channel tube 44b, is formed so that a uniform adhesive layer can be formed, and the pull-out strength is enhanced. The channel pipe 45 and the tip forming member 32 are fixed by solder.

Further, the distal end forming member 32 is provided with a hole 53 for forming a treatment instrument insertion channel 51 in the vicinity of the cylindrical body 38 which covers the image guide fiber 37, and the distal end portion of the connecting pipe 52 is distally provided on the rear end side thereof. Soldered to the component member 32.

The rear end of the connection pipe 52 is projected to the outside of the tip forming member 32, and the tip of the channel tube 54 is connected so as to fit the projection.
The channel tube 54 and the connection pipe 52 are bonded together. In this case, in order to make the adhesive layer of the channel tube 54 uniform and to improve the strength, the thread winding portion 55 is formed, and the adhesive layer is provided to such an extent that the thread is not uneven so that the thread is not frayed.

Further, the adhesive pipe 52 is provided with a taper portion 56 so that the treatment instrument can be smoothly inserted and removed in the treatment instrument insertion channel 51 without being caught. Therefore, the outer diameter of the tapered portion 56 of the connection pipe 52 becomes the maximum diameter of the connection pipe 52. As a result, the thread winding portion 55 of the channel tube 54 to which the thread winding is adhered is tightened to a small diameter, so that the fixing strength of the channel tube 54 becomes stronger.

Further, on both sides of the cylindrical body 38 which covers the image guide fiber 37, the light guide caps 58A and 58B on the tip side of the light guides 57A and 57B which are inserted through the inside of the insertion portion 31 and branched in the middle are tip ends. It is attached to the component member 32.

These light guides 57A and 57B are fixed by fixing screws 59A and 59B as shown in FIG. 6, and a silicone-based elastic adhesive 60 is applied on the light guides 57A and 57B for insulation.
Is filled.

Further, the frontmost bending piece 33 is screwed and fixed to the tip forming member 32 by two fixing screws 61 as shown in FIG. At this time, the relative position of the two fixing screws 61 is about 90 °.

A base 62 is provided on the front end side of the image guide fiber 37, and the front end of the base 62 has substantially the same outer diameter as the lens 63 bonded to the front end of the image guide fiber 37. A small diameter portion 64 finished to have a diameter is formed. Further, as shown in FIG. 8, on the rear end side of the mouthpiece 62, a first rear end side small diameter portion 67 for fixing a second protection tube 65 described later, a protrusion 69, and a second
Is provided with a small diameter portion 68.

Here, the tip portion of the first protection tube 66 formed of a silicon tube is fitted to the portion corresponding to the second small diameter portion 68, and is fixed by the silicone adhesive. Further, a second protective tube 65 for preventing the image guide fiber 37 from being broken is fitted. The tip side of the second protection tube 65 has a protrusion 6
After being fitted over 9 to the portion of the first rear end side small diameter portion 67, the outer peripheral surface of the second protective tube 65 is tightly bound with a thread, and the outer surface is covered with an adhesive.

The second protective tube 65 is made of porous tetrafluoroethylene resin and is highly flexible. As shown in FIG. 4, a chamfered portion 71 is provided at the tip of the second protective tube 65 to form a curl preventing means for preventing the tip of the second protective tube 65 from curling up.

Further, on the rear end side of the second protection tube 65, there is formed a hardening treatment portion 72 which is hardened by heat. Further, even if the second protection tube 65 moves in the axial direction, the flex portion of the flexible tube is not caught.

When assembling the endoscope, after soldering the channel pipe 45 and the connection pipe 52 to the distal end constituting member 32, an adhesive is applied to the connection pipe 52, a channel tube 54 is fitted, and tightly bound with a thread. Cover it with adhesive. Similarly, after the adhesive is applied to the channel pipe 45, the channel tube 44 of the air / water feeding channel 44
After b is fitted and bound by the thread, the adhesive is applied onto the thread.

After that, the cylindrical body 38 integrated with the lens 63 of the objective lens system 34 and the second lens frame 36 is inserted, and then the image guide fiber 37 is inserted and fixed by focusing.

Therefore, in the above structure, the chamfered portion 71 is provided at the tip of the second protective tube 65 to form a curl preventing means for preventing the tip of the second protective tube 65 from being curled up. Therefore, the tip component 32
Even if the diameter of the second protective tube 65 is reduced, it is possible to prevent the tip of the second protective tube 65 from turning up. Therefore, at the time of focusing, since there is no turning-up portion, the endoscope does not interfere with the fixed portions of the treatment instrument insertion channel 51 and the air / water feeding channel 44 which are adjacent to each other, and an endoscope with good assembling is obtained.

Further, as shown in FIG. 8, a hardening treatment portion 73 is provided at the tip of the second protection tube 65 so that the tip of the second protection tube 65 does not curl up even when bound by a thread. May be.

The hardening treatment section 73 is made by hardening a porous tetrafluoroethylene resin by crushing the porous portion thereof with heat. Alternatively, the porous portion may be impregnated with an adhesive or the like to be hardened. In this case, unlike the case where the chamfered portion 71 is provided at the tip of the second protection tube 65, there is no machining such as chamfering, so the cost is low.

FIG. 9A shows the flexible tube portion 81 of the insertion portion 2 of the endoscope 1 shown in FIG. This flexible tube section 8
Reference numeral 1 denotes a flex 82 wound in a spiral shape, a blade 83 arranged on the outer circumference of the flex 82, and an outer skin 84 arranged on the outer circumference of the blade 83, which are sequentially laminated.

Further, a front mouthpiece 85 is connected to the front end of the flexible tube portion 81, and a rear mouthpiece 86 is connected to the rear end thereof. The front cap 85 at the tip of the flexible tube portion 81 is connected to the rear end piece 22 of the bending portion 4.

In the flex 82, for example, two or more round wires, square wires, elliptical wires and the like are arranged in parallel to form a multi-strip strip material 87, and the strip strip material 87 is spirally wound. It is formed by a strip. The flexible portion 88 having a wide spiral pitch of the multi-strand strip 87 is provided on the tip side of the flex 82, and the hard portion 8 tightly wound on the hand side.
9. An intermediate hardness portion 90 having an intermediate hardness is formed in each of the central portions.

Therefore, in the above-mentioned structure, the flexibility is formed in a state in which the flexible portion 88 is formed at the distal end portion, the hard portion 89 is formed at the proximal side, and the intermediate hardness portion 90 is formed at the central portion. Since the flex 82 of the different multi-strip strip 87 is provided, the hardness of the flexible tube portion 81 can be effectively changed partially. Therefore, as compared with the case where the hardness of the outer cover 84 is partially changed stepwise by changing and mixing the soft resin and the hard resin sequentially.
The number of manufacturing steps can be simplified, and the variation in product quality can be reduced.

Further, since it is not necessary to change the hardness of the outer cover 84 in stages, the quality can be improved. Furthermore, since continuous molding is possible when molding the outer cover 84, the number of steps can be significantly reduced. It should be noted that higher elasticity can be obtained by selecting the material of the multi-stripe strip material 87 of the flex 82.

Further, the inside of the flexible tube portion 81 is shown in FIG.
As shown in (B) and (C), four coil pipes 91 ... Through which the bending operation wire 7 is inserted are arranged. The front end of each coil pipe 91 is brazed and fixed to the front cap 85 and the rear end of the flexible pipe 81 to the rear cap 86, respectively.

Further, for each coil pipe 91, for example, two or more round wires, square wires, elliptical wires, etc. are arranged in parallel to form a multi-strip strip material 92, and the strip sheet material 92 is wound in a coil shape. It is formed by a multi-stripe body.

In this case, the hardness can be arbitrarily changed by forming the coil of the strip plate material 92 of each coil pipe 91 to be coarse and dense. Therefore, it is effective when the hardness of the flexible tube portion 81 is partially changed stepwise.

Further, FIG. 9 (F) shows a connection state between the rear end piece 22 of the rearmost end of the bending portion 4 and the front mouthpiece 85 of the flexible tube portion 81. In this case, as shown in FIG.
As shown in (D), a narrowed portion 101 having a reduced outer diameter,
Pin engaging groove 10 extending along the axial direction of the flexible tube portion 81.
2 are formed.

Further, as shown in FIG. 9E, a ring-shaped engagement groove 103 with which the throttle portion 101 of the rear end piece 22 is engaged with the front mouthpiece 85 of the flexible tube portion 81 and a rotation stopper. And the engaging pin 104 of.

When the rear end piece 22 of the rearmost end of the bending portion 4 and the front mouthpiece 85 of the flexible tube portion 81 are connected, the engagement pin 104 of the front mouthpiece 85 is inserted into the pin engagement groove 102 of the rear end piece 22. While inserting, the throttle portion 101 of the rear end piece 22 is attached to the front mouthpiece 8
5 is engaged with the engaging groove 103. At this time, the narrowed portion 101 of the rear end piece 22 has a smaller diameter than the outer diameter of the front end portion of the front mouthpiece 85. Therefore, when the rear end piece 22 is fitted into the front mouthpiece 85, The rear end piece 22 is fitted into the front mouthpiece 85 while elastically deforming so that the rear end portion spreads the portion of the pin engaging groove 102.

Therefore, in the structure described above, when the rear end piece 22 of the curved end 4 and the front mouthpiece 85 of the flexible tube portion 81 are connected, the engagement pin 104 of the front mouthpiece 85 is moved to the rear end. The rear end piece 22 is fitted into the front mouthpiece 85 while being inserted into the pin engaging groove 102 of the piece 22 and with the narrowed portion 101 of the rear end piece 22 being engaged with the engaging groove 103 of the front mouthpiece 85. Therefore, the work can be simplified as compared with the case where the rear end piece 22 of the rearmost end of the bending portion 4 and the front mouthpiece 85 of the flexible tube portion 81 are connected by means such as screwing.

Further, in the state where the rear end piece 22 of the rearmost end of the bending portion 4 and the front mouthpiece 85 of the flexible tube portion 81 are connected, the engagement pin 104 of the front mouthpiece 85 and the pin of the rear end piece 22. The engagement portion with the engagement groove 102 prevents rotation in the circumferential direction, and the engagement portion with the narrowed portion 101 of the rear end piece 22 and the engagement groove 103 of the front mouthpiece 85 allows the flexible tube portion 81 to be prevented. Since the retainer is prevented in the axial direction, the rear end piece 22 of the rear end of the bending portion 4 and the front mouthpiece 85 of the flexible tube portion 81 can be reliably connected. Therefore, by providing a U-shaped groove-shaped tongue piece on the rear end piece 22 of the rearmost end of the bending portion 4 and caulking the tongue piece on the front mouthpiece 85 of the flexible tube portion 81, The reliability of the work can be enhanced as compared with the case where the rear end piece 22 and the front mouthpiece 85 of the flexible tube portion 81 are connected.

FIG. 10 shows a modification of the bending piece 13 for bidirectional bending of the bending portion 4 of the first embodiment.
The bending piece 13 of this modification is similar to the rivet holes 20 and 21 in FIG.
When the distance between the lower shoulder openings 23 and 25 is M and N, the shoulder openings 23 and 35 are set to protrude beyond the rivet holes 20 and 21 by M and N.

FIG. 11 shows the bending portion 4 of the second embodiment of the present invention. This is the wire guide 15 of the bending piece 13 for bending in two directions and the bending piece 1 for bending in four directions.
Bending angle restriction ring 11 between the wire guide 15 and the wire guide 15
1 is interposed through the operation wire 7 to regulate the bending angle.

In this case as well, similarly to the first embodiment, the bending piece 4 is rotated in the same direction as the bending direction of the bending portion 4, which is the bending angle of the bending piece connecting unit 12 before being attached to the endoscope body. The sum of the bending angles of the adjacent bending pieces 13 and 14 and the bending angle of the bending portion 4 in each bending direction, which is the bending angle of the bending piece connecting unit 12 when assembled in the endoscope body. Since the difference can be set to be substantially the same, the same effect as that of the first embodiment can be obtained.

FIG. 12 shows the bending portion 4 of the third embodiment of the present invention. This is because the wire guide 15 of the bending piece 13 for two-way bending and the wire guide 15 of the bending piece 14 for four-direction bending adjacent to this bending piece 13 are placed at positions where they protrude from the respective bending pieces 13 and 14. When attached and fixed and bent, the wire guides 15 come into contact with each other before the bending pieces 13 and 14 come into contact with each other, and the bending angle is regulated.

Also in this case, as in the first embodiment, the bending piece 4 is rotated in the same direction as the bending direction of the bending portion 4, which is the bending angle of the bending piece connecting unit 12 before being attached to the endoscope body. The sum of the bending angles of the adjacent bending pieces 13 and 14 and the bending angle of the bending portion 4 in each bending direction, which is the bending angle of the bending piece connecting unit 12 when assembled in the endoscope body. Since the difference can be set to be substantially the same, the same effect as that of the first embodiment can be obtained.

FIG. 13 shows the tip of the insertion portion 2 of the electronic endoscope 1 of the first embodiment. Here, the tip piece 21 is fixed to the tip forming portion 5 at the rear side of the cylindrical tip forming member 122 made of a hard member such as metal.

An objective lens system 124 is fixed to the tip forming member 122 via a lens frame 125. A part of the tip forming member 122 behind the objective lens system 124 is cut out to accommodate an image pickup section 126. ing. This imaging unit 12
Reference numeral 6 is composed of a CCD chip or the like. Further, a signal cable 127 is connected to the image pickup section 126, the signal cable 127 is inserted through the insertion section 2 and connected to the video processor 10.

The front end face and the outer periphery on the front end side of the tip forming member 122 are covered with a tip insulating cover 128, and the rear end side outer periphery of the tip forming member 122 is covered with a flexible outer cover 130. The outer periphery of the front end of the outer cover 130 is fixed to the tip forming member 122 by winding a thread.

On the upper side of the image pickup section 126, an air / water supply channel 131 is formed by a tube 132. The front end of the tube 132 is connected to the pipe 133 fitted in the hole of the tip forming member 122. The front end of this hole is enlarged in diameter to form a nozzle mounting hole 134 so that the nozzle 136 can be mounted through the insulating cylinder 135.

In addition, the tip-constituting member 122 has a structure shown in FIG.
As shown in FIG. 4, a hole for forming the treatment instrument insertion channel 137 is formed adjacent to the lens frame 125. The nozzle mouth jaw 138 at the tip of the nozzle 136 is attached so as to be in contact with the outer surface of the tip insulating cover 128.

The light guide caps 1 on the distal ends of the light guides 139A and 139B which are inserted into the insertion portion 2 on both sides of the treatment instrument insertion channel 137 and branched in the middle.
40A, 140B are attached to the tip component 122.

The lens frame 125 is fixed by a lens fixing screw 141 as shown in FIG. Further, as shown in FIG. 15, one light guide 139B is also fixed by the light guide fixing screw 142. These lens frames 12
5. Since the light guide 139B has a space for fixing screws around it, the flat point screws 141 and 142 are screwed into the normal screw holes, and the tips of the flat point screws 141 and 142 are attached to the outer circumference of the lens frame 125. The surface or the outer peripheral surface of the base 140B is pressed and fixed.

After the screws 141 and 142 are fixed, the filling holes 143 and 144 are filled with the filling material 145. Further, the screw 141 is provided with a protrusion at its tip, and this protrusion is engaged with the recess of the lens frame 125.

On the other hand, as shown in FIG. 14, since the space around the nozzle 136 is narrow, the nozzle 136 is fixed with a pointed screw 146. A screw hole 147 is provided on the side surface of the hole portion 134.

Further, the position of the central axis of the screw hole 147 is determined by inserting the insulating cylinder 135 having the nozzle 136 into the hole portion 13.
4, the conical portion 146A on the tip side of the pointed tip screw 146 can come into contact with the outer peripheral portion of the insulating cylinder 135.

The tip insulating cover 128 has the above-mentioned screw hole 1 when it is attached to the tip constituting member 122.
An escape hole 148 is provided at a position facing 47, and after the pointed screw 146 is fixed, the silicon-based filler 14
5 is filled.

Incidentally, in FIG. 14, the tip end insulating cover 1
Reference numeral 28 is used to prevent the cover from falling off by a cover falling prevention pin 149. In this embodiment, as shown in FIG. 15, the light guide 139A is fixed with a barbed screw 150.

The light guide 139A is composed of a fiber bundle formed by bundling a plurality of glass fibers including a core on the center side and a clad covering the core, and the tip end side of the light guide 139A is a light guide base 140A made of a metal pipe. Are glued together. This base 140A
Can be inserted into the light guide mounting hole 151 provided in the tip forming member 122.

The side surface of the mounting hole 151 has a screw hole 1
52 is provided, and the tip is a cone-shaped pointed screw 15
0 can be attached (screwed). The tip side conical portion 153 of the pointed tip screw 150 is the light guide base 1
The screw hole 152 is provided so that the central axis thereof is in contact with the outer circumference of 40A and the crossing angle is substantially right angle to the central axis of the mounting hole 151, and the screw hole 152 is in a twisted position.

As shown in FIG. 13, a diameter-increased mounting hole portion 154 is formed in a portion of the mounting hole portion 151 which is fixed by the pointed tip screw 150, and a spacer pipe 155 is inserted therein. , A pointed point screw 150
Is cut out so as not to interfere with.

Further, a light guide lens 156 is provided on the front surface of the emission end surface of the light guide 139A to which the light guide base 140A is attached.
It is fixed to the tip forming member 122 via 7.

Here, FIG. 16 shows a sectional view of the light guide 139B on the base end side. In FIG. 16, reference numeral 160 denotes a flexible tube portion of the insertion portion 2, and the flexible tube portion 160 is a flex 161 made of strip-shaped stainless steel or spring phosphor bronze.
A stainless steel wire and a reticulated tube 162 woven with a polyimide resin are covered thereover, and a polyurethane adhesive 164 is placed thereon.
And a polyurethane resin outer skin 163 is formed by a tubing method so that the mesh tube 162 is impregnated with the polyurethane resin.

FIG. 17 shows a fixing portion on the front end side of the light guide 139B. Here, the first protection tube 165 is provided on the base end side of the light guide base 140B.
Covers the light guide fiber.

Further, a second protective tube 167 is fitted on the outer side thereof, and the tip end portion thereof is tightly bound by a thread 168 over the flange 166 of the light guide base 140B, and the upper portion thereof Cover with adhesive 169,
The thread 168 is prevented from fraying. On the base end side of the second protection tube 167, a portion 170 is a hard portion as shown in FIG.

The second protective tube 167 is formed by drawing a porous tetrafluoroethylene resin, and the hard portion 170 is hardened by heat. Or, by changing the amount of stretching and changing the number of porous holes, the flexibility is changed,
It is stretched to a state as close as possible to the tetrafluoroethylene resin. The second protection tube 167 is also provided on the other light guide 139A and has the same configuration.

Therefore, in the case of the above structure, even when the insertion portion 2 is bent and the bending portion 4 is bent, the base end side of the second protection tube 167 is still rigid, so The base end side of the protection tube 167 of No. does not get caught in the gap of the flex 161. Therefore, the base end side of the second protection tube 167 is not caught in the gap of the flex 161, and the light guides 139A and 139B are not broken, and the durability is improved.

The present invention is not limited to the above embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0101]

According to the present invention, the difference between the sum of the bending angles of the adjacent bending pieces that rotate in the same direction as the bending direction of the bending portion and the bending angle of the bending portion in each bending direction of the bending portion is substantially equal. Since the bending angle setting means for setting the same state is provided, it is possible to improve the bending shape of the bending portion and facilitate observation and treatment.

[Brief description of drawings]

FIG. 1A is a side view showing a connecting unit of a bending piece according to a first embodiment of the present invention, FIG. 1B is a longitudinal sectional view showing a bending piece for bending in two directions, and FIG. FIG. 3D is a vertical cross-sectional view showing a bending piece for use with the bending piece, and FIG. 3D is a side view showing the bending state of the bending portion when the connecting unit of the bending piece is assembled to the endoscope main body.

FIG. 2 is a schematic configuration diagram of the entire system of an electronic endoscope.

FIG. 3 is a vertical cross-sectional view of a bending portion of an endoscope.

FIG. 4 is a vertical cross-sectional view showing the distal end portion of the insertion portion of the optical endoscope.

5 is a sectional view taken along line L ₁ -L _{1 of} FIG.

6 is a sectional view taken along line L ₂ -L _{2 of} FIG.

FIG. 7 is a sectional view taken along line L ₃ -L _{3 of} FIG.

FIG. 8 is a vertical cross-sectional view showing a fixing portion on the tip side of the first and second protection tubes of the image guide fiber.

9A is a side view showing a partial cross section of a flexible tube portion of an insertion portion of an endoscope, FIG. 9B is a cross sectional view showing a disposition state of a coil pipe in the flexible tube portion, FIG. (C) is a side view showing a partial cross-section of the arrangement of the coil pipes in the flexible tube portion,
(D) is a side view showing the pin engagement groove of the bending piece at the rearmost end of the bending portion, (E) is a side view showing the engagement pin of the front mouthpiece at the distal end of the flexible tube portion, and (F) is the rearmost end. FIG. 6 is a vertical cross-sectional view showing a connected state of the bending piece and the front mouthpiece of the flexible tube portion.

FIG. 10 is a vertical cross-sectional view showing a modified example of the bending piece.

FIG. 11 is a vertical sectional view showing a bending portion of a second embodiment of the present invention.

FIG. 12 is a vertical sectional view showing a bending portion of a third embodiment of the present invention.

FIG. 13 is a vertical cross-sectional view of the distal end portion of the insertion portion of the endoscope.

14 is a sectional view taken along line L ₁ -L _{1 of} FIG.

FIG. 15 is a sectional view taken along line L ₂ -L _{2 of} FIG.

FIG. 16 is a vertical cross-sectional view showing an end edge portion on the base end portion side of the second protection tube of the light guide.

FIG. 17 is a vertical cross-sectional view showing a fixing portion on the tip side of the first and second protection tubes of the light guide fiber.

FIG. 18 is a vertical sectional view showing a conventional bending piece.

[Explanation of symbols]

 2 ... insertion part, 4 ... bending part, 13, 14 ... bending piece.

[Procedure amendment]

[Submission date] April 27, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

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[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 4

[Correction method] Change

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[Figure 4]

[Procedure 3]

[Document name to be corrected] Drawing

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[Figure 5]

[Procedure amendment 4]

[Document name to be corrected] Drawing

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[Figure 6] ─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] July 20, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 4

[Correction method] Change

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[Figure 4]

Claims (1)

[Claims] 1. A plurality of bending pieces arranged in parallel in the insertion direction of the insertion portion are rotatably connected to each other, and each of the bending pieces is provided with a bending portion capable of bending in at least two directions. In the endoscope set in such a state that the sum of the bending angles of the adjacent bending pieces that rotate in the same direction as the bending direction of the bending portion is larger than the bending angle of the bending portion in each bending direction, Angle setting means for setting the difference between the sum of the bending angles of the adjacent bending pieces that rotate in the same direction as the bending directions of the bending portions and the bending angle of the bending portions in the bending directions of the bending portions to substantially the same state. An endoscope characterized by being provided with.