JP2001190493A - Electronic endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic endoscope which is excellent in observation performance and curving operability and is made smaller in the diameter of an insertion section. SOLUTION: Curving wires 29 and 29 are arranged on a region 2A side which is a left side half divided by a one end face extension line at which one end protrudes when the right end in Figure of the maximum external form projected part of an image pickup unit indicated by a broken line of the image pickup unit 45 protrudes by a size (a) by crossing the perpendicular axis facing the upper and lower curving direction passing the center section of the insertion part 2. A connecting pipe 38, a tube 37 for a channel and light guides 39 and 39 are arranged in a region B divided by the one end face extension line.

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 the diameter of an insertion portion is reduced.

[0002]

2. Description of the Related Art Conventionally, an elongated insertion portion is inserted into a body cavity, and a medical endoscope for observing the inside of the body cavity, or an industrial endoscope used for observing and inspecting inside a tube of a machine or a chemical plant. Endoscopes are widely used.

[0003] As such an endoscope, there is an electronic endoscope in which a solid-state imaging device such as a CCD is arranged at a distal end portion of an insertion portion to constitute an imaging unit. The electronic endoscope is provided with a treatment instrument channel for inserting a light guide for supplying illumination light, a treatment instrument, and the like.

In the electronic endoscope, an elongated endoscope insertion section is inserted into a small-diameter, meandering tube or lumen.
In order for the endoscope insertion part to be inserted smoothly even a little,
It has been desired to reduce the outer diameter and the hard length of the distal end portion in which the imaging unit is built.

For example, in an endoscope disclosed in Japanese Patent Application Laid-Open No. 5-38325, an image pickup unit having a rectangular cross-section is formed by interposing a center axis in a vertical direction of a cross section of the endoscope tip (see other figures). The upper and lower sides of the imaging unit are disposed on one side, and a channel tube is disposed on the other side, and a string guide for fixing a bending wire to the bending tube is disposed above and below the channel tube. An electronic endoscope has been constructed by arranging a light guide in a space surrounded by a string guide (wire receiver) and a joint piece inscribed circle.

In recent years, as the size of the imaging unit has been reduced and the diameter of the insertion portion has been further reduced, the area around the CCD, which is the largest cross-sectional shape of the imaging unit, in an electronic endoscope with a treatment instrument channel has been increased. It occupies nearly half of the area that makes up the endoscope end.

For this reason, a curved wire is set up and down with a channel tube in between as in the prior art, and a light guide is arranged in the space surrounded by the inscribed circle of the imaging unit, string guide and joint piece as described above. If you try,
Since the space area for arrangement is reduced, the number of strands constituting the light guide must be reduced and the diameter of the light guide must be reduced. However, when the light guide is configured by reducing the number of strands,
There is a possibility that the amount of illumination light may be reduced and obstruct observation. For this reason, in order to install the light guide without changing the number of strands, that is, without reducing the amount of illumination, the arrangement position of the curved wire is set near the channel tube to secure the light guide arrangement space. .

[0008]

However, by setting the bending wire installation position closer to the channel tube, the bending wires are brought closer to each other in the bending direction, and the two bending wires are placed on one side. In addition, not only the bending operation becomes heavy, but also when the bending portion is bent at the time of the bending operation, there is a problem that the bending wire is largely warped in a direction in which the bending wire is disposed. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an electronic endoscope which is excellent in observation performance and bending operability and has a reduced diameter of an insertion portion.

[0010]

An electronic endoscope according to the present invention comprises:
An objective optical system and a body cavity including an illumination optical system that is located on the distal end side and emits illumination light to an observation site, an imaging unit provided with a solid-state imaging device that captures an optical image of the observation site illuminated by the illumination optical system, and An insertion portion having a distal end main body having an opening of a channel for introducing a treatment instrument or the like therein, and a bending portion connected to the distal end main body and configured to bend in two upward and downward directions; An electronic endoscope fixed to the base end side and including an operation section having an operation knob for pulling a bending wire for bending the bending section, wherein the insertion section is viewed from the distal side, When one end surface of the maximum outer shape projection unit of the imaging unit has a size crossing a vertical axis passing through a center portion, the up-down curved wire is divided into two by an extension line of one end surface crossing the vertical axis,
The image pickup unit is arranged on one side including the image pickup unit in a positional relationship sandwiching the image pickup unit.

[0011] According to this configuration, the bending wire is prevented from being displaced to one side, and the heavy bending operation and the bending of the bending portion are reliably prevented.

[0012]

1 to 5 relate to an embodiment of the present invention. FIG. 1 is a diagram illustrating an electronic endoscope, and FIG. 2 is a diagram illustrating a distal end side of an insertion portion of the electronic endoscope. FIG. 3 is a sectional view taken along line BB of FIG. 2, FIG. 4 is a sectional view taken along line CC of FIG. 2, and FIG. 5 is a sectional view taken along line DD of FIG.

FIG. 2A is a view of the distal end of the insertion portion as viewed from the front, and FIG. 2B is a sectional view taken along line AA of FIG. 2A.

As shown in FIG. 1, an electronic endoscope 1 according to the present embodiment has an elongated and flexible insertion section 2, an operation section 3 connected to the rear end of the insertion section 2, It has flexibility extending from the side of the operation unit 3 and is mainly constituted by a universal cable 4 in which an imaging cable, a light guide, and the like are inserted. Reference numeral 4a denotes an electrical connector detachably connected to a video processor (not shown) disposed at the base end of the universal cable 4.

The insertion section 2 includes a distal end constituting section 24 which constitutes a distal end section 21 containing a solid-state image pickup element, a bending section 22 which connects a plurality of articulated pieces described later and can be bent vertically.
The flexible tube section 23 having flexibility is sequentially connected from the distal end side.

The operation unit 3 has a switch unit 31 for controlling a video processor (not shown) such as a freeze of an endoscopic observation image displayed on a monitor screen (not shown);
A bending operation knob 32 for bending the bending portion 22
Further, a treatment instrument insertion port 33 for inserting the treatment instrument is provided.

As shown in FIG. 2A, an observation lens cover 4 constituting an observation optical system, which will be described later,
1 and an illumination lens cover 35 for emitting illumination light transmitted from a light source device (not shown) via a light guide inserted into the universal cable 4, the operation unit 3, and the insertion unit 2 toward a target observation site. Are located. Reference numeral 36 denotes a treatment tool opening from which the treatment tool inserted from the treatment tool insertion port 33 projects.

As shown in FIGS. 2 (b), 3 and 4, the distal end portion 24 constituting the distal end portion is formed in a substantially cylindrical shape by a metal member, and the distal end portion is covered with an insulating cover 11 made of resin. ing.

The distal end portion 24 includes an observation lens cover 41 and a first lens frame 43 and a second lens frame 44 for supporting a plurality of lens groups 42 constituting an observation optical system 40 which is a built-in endoscope. A through hole for an observation optical system to be disposed, a through hole for a tube for disposing a connection tube 38 for disposing a channel tube 37 formed of a flexible soft member, and an illumination optical system. Is formed for disposing the light guide 39.

The falling-off preventing portion 11a protruding from the insulating cover 11 to the base end side is provided with a fixing pin 9 on the front end forming portion 24.
a, and the second lens frame 44 is integrally fixed to the distal end portion 24 by screws 9b.

The holes for disposing the fixing pins 9a and the fixing screws 9b are formed in the same direction in consideration of workability. Reference numeral 9c is a sealing resin member that closes the screw hole.

A bending portion 2 is provided at the base end of the tip configuration portion 24.
2 are fixed, and a plurality of joint pieces 25 are attached to the base end side of the distal joint piece 25a.
rivet 2 so that b, ..., 25n bend smoothly
6 form a curved tube 25 which is connected rotatably. .., 25n.
The outer tube 27 is covered on the outer periphery of the curved tube 25 which is rotatably formed by connecting the outer tube 27 and the outer tube 27.

Reference numeral 28 denotes one of two ring-shaped wire receivers provided on the inner peripheral surface side of the distal joint piece 25a. Each of the wire receivers 28 has one end attached to the bending operation knob 32. The other end of the curved wire 29 to which is fixed is fixed. A wire guide (not shown) for guiding the bending wire 29 also to the bending tube 25.
Are provided.

On the other hand, reference numeral 45 in the figure denotes a main part of the built-in endoscope, and a solid-state image sensor 45a is provided at an image forming position of the observation optical system.
Is an imaging unit configured by arranging the imaging planes. In the imaging unit 45, a cover glass (not shown), a solid-state imaging device 45a, a circuit board (not shown), and the like are arranged in series in the longitudinal direction of the insertion section 2 in order from the distal end side.
From the base end of the imaging unit 45, a signal cable 46 in which a plurality of coaxial lines and the like connected to the circuit board and the solid-state imaging device 45a are extended to the electric connector 4a.

Here, referring to FIG. 5, the image pickup unit 45, the wire receiver 28, the curved wire 29, and the connecting pipe 3 will be described.
8 and the relationship between the channel tube 37 and the light guide 39 will be described.

As shown in the figure, one end face (right end in the figure) of the imaging unit maximum outer shape projection part shown by a broken line of the imaging unit 45 is a vertical axis passing through the center of the insertion part 2 and going in the vertical bending direction. And protrudes beyond this vertical axis by dimension a.

When the one end face of the imaging unit maximum outer shape projection part protrudes from the vertical axis as described above, the position is sandwiched by the imaging unit 45 on the side of the area 2A corresponding to the left half in the figure divided by the one end face extension line. The bending wires 29, 29 are arranged in relation to each other. At this time, the area 2B which is the right half in the figure divided by the one end surface extension line
, A connection tube 38, a channel tube 37, and light guides 39, 39 are arranged.

That is, the bending wires 29, 29, which are wires for bending up and down, are located in the region 2A in the vicinity of the vertical axis and within the distal end joint piece 25a, which is substantially opposed to each other across the imaging unit 45. It is fixed to two wire receivers 28, 28 fixed on the peripheral surface. Accordingly, the space in which the bending wires 29 and 29 are disposed is in a range surrounded by the inscribed circle of the joint piece 25a, the extension of the one end surface, and the outer periphery of the imaging unit maximum outer shape projection unit, while the connection tube 38 and the channel tube 37 are provided. The space where the light guides 39 and 39 are disposed is a range surrounded by the inscribed circle of the joint piece 25a and the extension of the one end surface.

Therefore, the area surrounded by the inscribed circle of the joint piece 25a, the extension of the one end surface, and the outer periphery of the channel tube 37 is secured as a space for disposing the light guide 39. That is, by setting the outer dimensions of the channel tube 37 arranged in the inscribed circle of the joint piece 25a in advance and forming the maximum outer projection unit of the imaging unit, the number of wires is not changed, that is, the amount of illumination light is reduced. The installation of a light guide is possible. At this time, the light guide 3
9 may be formed in a flat shape and arranged in a range surrounded by the inscribed circle of the joint piece 25a, the extension of the one end surface, and the outer periphery of the channel tube 37. Notches are formed at the four corners of the imaging unit 45 in consideration of the disposition of the built-in object in the internal space of the insertion section.

When the insertion portion having a small diameter is viewed from the front end side, when one end surface of the maximum outer shape projection portion of the image pickup unit has a size crossing a vertical axis passing through the center portion, the one end surface portion is formed. By arranging the upper and lower curved wires such that the curved wires face each other on the region side including the imaging unit divided by the extension line,
It is possible to prevent the bending tube from inclining to one side during bending and increase the amount of bending force.

The present invention is not limited to only the above-described embodiments, but can be variously modified without departing from the gist of the invention.

[Appendix] According to the above-described embodiment of the present invention as described in detail above, the following configuration can be obtained.

(1) An imaging unit provided with an illumination optical system for emitting illumination light to an observation site and a solid-state imaging device for imaging an optical image of the observation site illuminated by the illumination optical system is provided on the distal end side. A distal end main body having an objective optical system having a channel opening for introducing a treatment instrument or the like into a body cavity, and an insertion portion having a curved portion connected to the distal end main body and configured to bend in two vertical directions. And an operation section fixed to the base end side of the insertion section and having an operation knob for pulling a bending wire for bending the bending section, the operation section including the operation section. As viewed from above, when one end surface of the maximum outer shape projection unit of the imaging unit is large enough to cross a vertical axis passing through the center, the vertically curved wire is divided into two by an extension of one end surface crossing the vertical axis. Divided Electronic endoscope disposed in the positional relationship across the imaging unit in one region side including the image pickup unit.

(2) The electronic endoscope according to appendix 1, wherein an arrangement position of the illumination optical system is set in a range surrounded by the inner surface of the insertion portion, the extension of the one end surface, and a channel.

(3) In an electronic endoscope having at least an image pickup unit, two curved wires, two light guides, and a channel tube in the insertion portion, the positional relationship of the built-in object in the position cross section is determined by a watch. An electronic endoscope in which a curved wire, a light guide, a tube for a channel, a light guide, a curved wire, and an imaging unit are arranged in this order.

[0036]

As described above, according to the present invention, it is possible to provide an electronic endoscope which is excellent in observation performance and bending operability and has a reduced diameter of the insertion portion.

[Brief description of the drawings]

FIG. 1 to FIG. 5 relate to an embodiment of the present invention,
FIG. 1 is a diagram illustrating an electronic endoscope.

FIG. 2 is a diagram illustrating a distal end side of an insertion portion of the electronic endoscope.

FIG. 3 is a sectional view taken along line BB of FIG. 2;

FIG. 4 is a sectional view taken along line CC of FIG. 2;

FIG. 5 is a sectional view taken along line DD of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope 45a ... Solid-state image sensor 28 ... Wire receiver 29 ... Curved wire 37 ... Channel tube 38 ... Connection tube 39 ... Light guide

[Procedure amendment]

[Submission Date] October 25, 2000 (2000.10.
25)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 1

[Correction method] Change

[Correction contents]

FIG.

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Figure 3

[Correction method] Change

[Correction contents]

FIG. 3

[Procedure amendment 3]

[Document name to be amended] Drawing

[Correction target item name] Fig. 4

[Correction method] Change

[Correction contents]

FIG. 4

Claims (1)

[Claims] An illumination optical system that emits illumination light to an observation site and a solid-state imaging device that captures an optical image of the observation site illuminated by the illumination optical system are provided at a distal end side. A distal end body provided with an objective optical system and a channel opening for introducing a treatment instrument or the like into the body cavity, and an insertion portion having a curved portion connected to the distal end body and configured to bend in two vertical directions. An operation section fixed to the base end side of the insertion section and having an operation knob for pulling a bending wire for bending the bending section, the operation section comprising: When viewed, when the one end face of the maximum outer shape projection part of the imaging unit has a size crossing a vertical axis passing through a center portion, the vertical bending wire is divided into two by an extension of one end face crossing the vertical axis. And before An electronic endoscope, characterized in that arranged in the positional relationship across the imaging unit in one region side including the imaging unit.