JPH071612Y2 - Endoscope - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an endoscope having an electronic component built in its distal end.

[Technical background of the device and its problems]

In recent years, along with the multifunctionalization of endoscopes, computerization is progressing.
For example, an endoscope using a solid-state image pickup device as an observing means is provided (see Japanese Patent Laid-Open No. 58-69528).

By the way, the electric wire led out from the fixed image pickup device incorporated in the distal end portion and its attached electronic components is guided through the long insertion portion. In this case, if each electric wire is disjointed, other built-in members such as light guide, image guide,
It may hit the tubes directly and may be entangled with them, thus preventing damage.

Therefore, in an unpublished prior application, it is considered that the electric wires are bundled and protected by a protective tube.

However, merely by fitting the protective tube over the electric wire, the effect of preventing disconnection or the like is small. That is, when the insertion portion is bent, the electric wire and the protection tube move in the axial direction, but the movement amount of each member is different. Therefore, particularly when the electric wires are so filled as to compete with each other in the protective tube, a large frictional force is generated between the electric wires and the protective tube. Then, the electric wire is repeatedly buckled or excessively pulled, and finally the wire is broken. As for the location of disconnection, not only in the middle of the electric wire, but also at the soldered portion on the printed circuit board or the like, the disconnection is likely to occur.

[Purpose of device]

The present invention has been made in view of the above circumstances, and an object thereof is to provide an endoscope in which the durability of a shielded wire and its tangent portion derived from an electronic component provided at the endoscope distal end portion is improved. To do.

[Outline of device]

The present invention is an endoscope in which an electronic component is provided at a distal end portion of an endoscope and a shielded electric wire derived from the electronic component is guided through the insertion portion. In the endoscope, the shielded electric wire is inserted through the insertion portion and is protected. An endoscope characterized in that the tube is loosely inserted so that there is a gap between the outer diameter of the shielded electric wire and the inner diameter of the protective tube.

[Example of device]

FIG. 1 shows the entire endoscope apparatus, 1 is an endoscope, 2 is an endoscope control apparatus, and a video process circuit 3 is built in the endoscope control apparatus 2. A monitor 4 connected to the video process circuit 3 is provided outside the endoscope control device 2.

The distal end portion of the insertion portion 5 of the endoscope 1 is configured as shown in FIG. That is, the distal end portion is provided with a distal end constituent member 7 connected to the distal end of the bending tube 6 connected to the distal end of the flexible tube (not shown) of the insertion section 5,
Various members are incorporated in the tip forming member 7 as described later. The tip forming member 7 may be made of metal, but may be made of synthetic resin or ceramic. The bending tube 6 is formed by covering the outer circumference of a core member, which is formed by rotatably connecting a plurality of bending pieces 8 with each other, with an outer cover 9 made of electrically insulating synthetic resin.

A tip cover 11 made of an electrically insulating material is tightly fitted on the outer peripheral surface of the tip constituent member 7. Further, an objective observation unit 12, which will be described later, is detachably attached to the distal end constituent member 7. Further, an illumination lens 13 is airtightly provided on the distal end constituent member 7 side by side with the objective observation unit 12,
The tip of a light guide 15 made of an optical fiber bundle is connected to the inside of the illumination lens 13. The tip portion of the light guide 15 penetrates the tip component member 7 and is fixed to the tip component member 7. Further, the illumination lens 13 is the above-mentioned tip cover.
The outer end surface of the illuminating lens 13 is fitted in a hole 16 penetrating through 11 in an airtight manner and adhered thereto.
It is recessed deeper inward than the outer end face. That is, the tip cover 11 forms the wall 17 around the illumination lens 13. As a result, the illumination light does not directly enter the objective lens side described later, and flare is prevented.

Further, the tip component member 7 is provided with an air / water feeding nozzle 18 penetrating the tip cover 11 and protruding to the outside, and the air / water feeding nozzle 18 has an air / water feeding tube 19 inserted into the insertion portion 5.
Are connected. The air / water nozzle 18 is made of an electrically insulating material.

Further, the tip forming member 7 includes a tubular channel tip member.
A hole 22 into which the 21 is inserted is penetrated, and a circumferential groove 24 into which an O-ring 23 is fitted is formed on the outer periphery of the channel tip member 21. That is, the channel tip member 21 is hermetically fitted in the hole 22 by the O-ring 23. The channel tip member 21 is fixed in place by a retaining screw 25 that is screwed into the side wall of the tip forming member 7. The attaching position of the retaining screw 25 is sealed by filling an electrically insulating potting material 30. Also,
The opening 26 of the channel tip member 21 communicates with the channel hole 27 opened in the tip cover 11. Further, the channel tip member 21 is connected to a channel tube 28 inserted into the insertion portion 5. An insertion channel 29 is formed by the inside of the opening 26, the channel hole 27, and the channel tube 28 so that various treatment tools can be inserted.

On the other hand, the objective observation unit 12 includes an objective lens system 33, an electronic component such as a solid-state image sensor 34 and its flexible substrate 35, and an electric wire 36 connected to the flexible substrate 35.
Is at least incorporated. The electric wire 36 is a shielded electric wire as described later. Electronic components 31 such as transistors, capacitors and resistors are attached to the flexible substrate 35. In the objective lens system 33, a plurality of lenses 37 are hermetically bonded and fixed in a lens frame 38 made of metal, and an observation cover lens 39 is fixedly attached to the tip of the lens frame 38. A diaphragm hole 40 formed by a part of the lens frame 38 is provided between the plurality of lenses 37 and the observation cover lens 39. Further, an electrically insulating lens frame cover 41, which is airtightly adhered, is fitted on the outer periphery of the lens frame 38. The tip of the lens frame cover 41 projects outward beyond the tip of the lens frame 38 and further beyond the tip surface of the tip cover 11. The protruding tip edge 42 of the lens frame cover 41 protrudes around the observation cover lens 39 to prevent the illumination light from the illumination lens 13 side from directly entering the objective lens system 33 and prevent so-called flare. It is like this. A space between the periphery of the observation cover lens 39 and the front end of the lens frame cover 41 is sealed by filling an insulating potting material 43. That is, the lens frame 38 is not exposed to the outside.

Further, the outer periphery of the lens frame cover 41 is closely fitted and inserted into the through hole 45 formed in the distal end constituent member 7, and is detachably attached. That is, a peripheral groove 47 into which the O-ring 46 is fitted is formed on the outer peripheral surface of the lens frame cover 41. That is, the lens frame cover 41 is airtightly inserted into the through hole 45 by the O-ring 46. Further, the lens frame cover 41 is fixed in place by a retaining screw 48 that is screwed into the side wall of the tip forming member 7. The attaching position of the retaining screw 48 is hermetically sealed to the outside by filling an electrically insulating potting material 49.

On the other hand, the solid-state image pickup device 34 is made of metal and is attached inside a tubular device frame 51. The outer diameter of the solid-state image sensor mounting portion of the element frame 51 is larger than the outer diameter of the lens frame cover 41. The tip of the element frame 51 is the lens frame 38.
Is bonded to the outer circumference of the sheet and is fixed by adhesion with a conductive adhesive. The lens frame cover 41 is fitted on the outer periphery of the tip portion of the element frame 51.

In addition, a flexible substrate 35 connected to the solid-state image sensor 34
Is a shield pipe screwed to the rear end of the element frame 51.
Surrounded by 52. The shield pipe 52 is made of metal and is electrically connected to the element frame 51. The shield pipe 52 extends rearward so as to include the connecting end portion of the electric wire 36. A metal wire fixing member 53 is connected to the rear end of the shield pipe 52 and is electrically connected to the shield pipe 52. That is, the lens frame 38, the element frame 51, the shield pipe 52, and the wire fixing member 53 are electrically connected to each other, and these form a long tubular shield member 54.

An electric wire protection tube 55 is connected to the outer periphery of the rear end of the electric wire fixing member 53. And the wire 36 is this wire protection tube
It is guided through 55 and is connected to the video process circuit 3 as shown in FIG. The tip portion of the electric wire 36 is inserted into the electric wire fixing member 53, and is fastened and fixed to the electric wire fixing member 53 by a string 56. The electric wire 36 is composed of a shield wire, and the wire 57 that is in charge of the shield.
Is electrically connected to the flexible substrate 35 and the wire fixing member 53.

The electric wire protection tube 55 is made of a long flexible tube material and is guided through the endoscope 1 including the insertion portion 5. That is, it is guided through the inside of the insertion section 5, the operation section 70, and the light guide cable 71.

The electric wires 36 are twisted together as shown in FIG. Further, the inner diameter of the wire protection tube 55 is made sufficiently large with respect to the diameter of the outer diameter envelope circle of the twisted wires 36. That is, the electric wire 36 is loosely inserted into the electric wire protection tube 55. For example, the ratio of the area of the outer diameter envelope circle of the bundle of wires 36 to the inner hole cross-sectional area of the wire protection tube 55 is 50%.
Below.

Each of the shield pipe 52 and the wire fixing member 53 is densely filled with an electrically insulating potting agent 58.
Therefore, the shield pipe 52 and the wire fixing member
The flexible substrate 35 inside the 53, the electric wire 36 and their connecting ends are embedded in the electrically insulating potting agent 58.

On the other hand, an electrically insulating tube 59 is tightly fitted on the outer peripheries of the element frame 51 and the shield pipe 52. The tip of the tube 59 is fitted on the outer periphery of the rear end of the lens frame 38 and is fastened by a string 60. Also,
The rear end of the tube 59 is fitted on the outer circumference of the electric wire protection tube 55 fitted on the outer circumference of the electric wire fixing member 53, and is fastened by a string 61. The potting agent 62 is filled inside the tip of the tube 59 and around the element frame 51.

For each of the potting agents 30, 43, 49, 58, 62, an epoxy-based or silicon-based electrically insulating adhesive is used, for example.

The electric wire 36 is loosely inserted into the electric wire protection tube 55.

By the way, when the endoscope is used, when the insertion portion 5 and the light guide cable 71 are bent, the electric wire 36 and the electric wire protection tube 55 are displaced from each other in the axial direction. However, since the electric wire 36 is loosely inserted into the electric wire protection tube 55, no frictional force is generated between the two.

Further, by twisting, the excessive movement of the electric wire 36 is restricted, and the electric wire 36 has elasticity in the axial direction. Therefore, even if the insertion portion 5 and the light guide cable 71 are repeatedly bent,
An excessive frictional force is not applied to the electric wire 36, and an excessive compressive force is not applied, so that the electric wire 36 does not buckle. Further, since an excessive pulling force is not applied, breakage of the brazed connection portion of the electric wire 36 is prevented.

Further, since the plurality of electric wires 36 are twisted together, the force applied to one of the electric wires 36 is averaged as compared with the case where the electric wires 36 are separated one by one. Therefore, the strength of only one wire is prevented from being weakened, and the durability as a whole is improved.

Further, since the electric wire protection tube 55 is fitted, it becomes easy to slip, and the influence of other built-in objects, for example, rubbing against other electric wires, snarling, and catching is eliminated. From this point, too, no excessive force is applied to the electric wire 36, and no excessive force is applied to the connecting portion with the flexible substrate 35, so that the durability can be improved.

Furthermore, since the electric wire protection tube 55 is thick enough for the electric wire 36 side, it is possible to block mechanical influences received from other built-in objects and prevent it from being directly transmitted to the electric wire 36. Also in this respect, the durability of the electric wire 36 itself or the connection portion is improved.

In general, in this type of solid-state image sensor type endoscope, the electric wire 36
The outer diameter of the bundle can be made smaller than the outer diameter of the image guide of the image guide type endoscope. By the way, the thickness of the insertion portion is appropriate for each model. Therefore, it is not enough to simply reduce the diameter. Therefore, depending on the model used, when the solid-state image sensor type is used, the filling rate of built-in objects may be low.

When the filling rate of the built-in items is low, the initial position of the built-in items collapses due to the bending of the built-in items as the bending of the built-in items is repeated.

On the contrary, if the filling rate of the built-in objects is high, the frictional force between the built-in objects becomes large, and the durability of the built-in objects also deteriorates.

Therefore, when the electric wire protection tube 55 is provided, the outer diameter of the protection tube 55 is selected to select an appropriate filling rate. The filling rate of this internal component is usually 55-65%.
The degree is good, especially around 60% is desirable.

In the configuration of the above embodiment, adjusting the filling rate is convenient because the electric wire 36 can be inserted more loosely into the electric wire protection tube 55.

Although the electric wires 36 are twisted and bundled in the above embodiment, the present invention is not limited to this type. Each electric wire 36
May be parallel to each other. In this case, as for the filling rate of the electric wire 36, the sum of the cross-sectional areas of the electric wire 36 is the electric wire protection tube 55.
Of the inner hole cross-sectional area. Particularly, the filling rate is preferably 8% to 70%.

[Effect of device]

As described above, the present invention is a protective tube in which a shielded wire derived from an electronic component provided at the distal end portion of an endoscope is inserted and disposed in an insertion portion. The frictional force between the protective tube and the shielded electric wire can be greatly reduced because it is inserted so loosely that there is a gap. Therefore, the shielded electric wire does not buckle or an excessive pulling force is applied even if it is repeatedly bent. In addition, the shield effect of the shielded wire itself and its connection is prevented, and the shielded wire of the shielded wire is not deteriorated and the shielded wire or core wire is not damaged. Also, the durability of the sealed electric wire itself can be significantly improved.

[Brief description of drawings]

FIG. 1 is a schematic view of an endoscope apparatus according to an embodiment of the present invention, and FIG.
Similarly, the figure is a sectional view of the distal end portion of the endoscope. DESCRIPTION OF SYMBOLS 1 ... Endoscope, 5 ... Insertion part, 7 ... Tip component member, 31 ... Electronic component, 34 ... Solid-state image sensor, 36 ... Electric wire, 55 ... Electric wire protection tube.

Claims (1)

[Scope of utility model registration request] 1. An endoscope in which an electronic component is provided at a tip portion of an endoscope, and a shielded electric wire derived from the electronic component is guided through the insertion portion, the shielded electric wire being inserted and disposed in the insertion portion. An endoscope characterized in that it is inserted into a protective tube loosely so that there is a gap between the outer diameter of the shielded electric wire and the inner diameter of the protective tube.