JP3222529B2 - Electronic endoscope tip - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distal end of a so-called electronic endoscope in which a solid-state image pickup device is built in the distal end of an insertion portion of the endoscope.

[0002]

2. Description of the Related Art In a conventional electronic endoscope, a solid-state image sensor and a circuit board are integrally connected and fixed at an end of an insertion portion with an adhesive so as not to move with each other. In addition to joining with the objective optical system, a signal cable is connected to the circuit board by soldering or the like, and the whole is configured as one unit.

[0003]

Since the signal cable is inserted through the entire length of the insertion portion of the endoscope, if the insertion portion is looped or the bending portion formed in the insertion portion is fully bent, the signal cable is not inserted. The cable is pushed and pulled strongly.

Then, the force reaches the objective optical system via the circuit board and the solid-state imaging device, and the bonding between the solid-state imaging device and the objective optical system is peeled off, and the bonding between the optical components in the objective optical system is peeled off. Was sometimes done. In particular, when it is put in a sterilizer or the like and becomes a high temperature state, it becomes easy to peel off.

Accordingly, an object of the present invention is to provide a distal end portion of an electronic endoscope in which a joint of an objective optical system or the like does not peel even if a signal cable is pushed or pulled.

[0006]

In order to achieve the above object, the distal end of an electronic endoscope according to the present invention is fixedly connected to an objective optical system provided at the distal end of an insertion portion of the endoscope and a solid-state imaging device. In addition, the circuit board is flexible with respect to the solid-state imaging device at the distal end of the electronic endoscope in which the circuit board to which the signal cable is connected and the solid-state imaging device are connected and connected within the distal end of the insertion portion. Characterized in that they are connected to each other.

The circuit board may be fixed to the distal end of the insertion section of the endoscope, and an elastic filling around the connecting section between the circuit board and the solid-state imaging device in the distal end of the insertion section. An agent may be filled.

[0008]

An embodiment will be described with reference to the drawings. FIG. 2 is a front view of a distal end portion of the electronic endoscope, and FIG. 1 is a cross-sectional view taken along a line II.

In FIG. 1, reference numeral 1 denotes a curved portion formed at the distal end of an elongated flexible tube forming an insertion portion, and a plurality of node rings 2 are rotatably connected by rivets. The outer periphery is covered with a mesh tube 4 made of a thin metal wire and a jacket tube 5 made of rubber.

A bending operation wire 7 which is remotely pulled and operated.
Are inserted in a wire guide 8 projecting inward from each node ring 2 so as to be able to advance and retreat. The distal end of each bending operation wire 7 is fixed to the most advanced wire guide 8 by silver brazing. Reference numeral 9 denotes a stopper pipe for securing the wire guide 8, which is fixed to the end of the leading-edge wire guide 8 by silver brazing or the like.

Reference numeral 11 denotes a distal end main body connected to the distal end of the curved portion 1 via a connecting tube 12;
And a head 11a made of an electrically insulating plastic and joined to a tip portion thereof.

The tip body 11 is located on the tip side (left side in FIG. 1).
It has a circular cross-sectional shape as viewed from above, and the objective optical system 13 is built therein. The objective optical system 13 includes an objective lens group 13a including a plurality of lenses, a color correction filter 13b, a low-pass filter 13c, and a right-angle prism 1
3d.

The axial direction of the objective lens group 13a coincides with the axial direction of the distal end main body 11, and the object ahead is the subject. The observation window 14 is formed by the most advanced lens of the objective optical system 13.

Reference numerals 15 and 16 denote mirror frames into which an objective lens group 13a including a cemented lens is fitted and adhered. 17 is the aperture stop. Reference numeral 18 denotes an O-ring for sealing. Reference numeral 20 shown in FIG. 2 denotes an illumination window, from which illumination light transmitted through the illumination light guide fiber bundle is radiated outward to illuminate a subject in front of the distal end body 11.
21 and 22 are air / water nozzles. 23 is an outlet of the forceps channel.

As shown in FIG. 1, a solid-state image pickup device 31 is disposed in the body 11b of the distal end main body 11. As the solid-state imaging device 31, for example, a CCD (charge coupled device) is used.

The image receiving surface 31a of the solid-state image sensor 31 is formed in a square or rectangular shape, and is arranged parallel to the optical axis of the objective lens group 13a.

The right-angle prism 13d disposed between the objective lens group 13a and the solid-state image sensor 31 causes the optical axis of the objective optical system 13 to intersect perpendicularly with the center of the image receiving surface 31a of the solid-state image sensor 31. At right angles.

Right angle prism 13d and objective lens group 13a
And a connecting cylinder 19 connected to the rear half of the lens frame 16.
Inside, the light shielding mask 25, the color correction filter 13b, and the low-pass filter 13c are joined and interposed, and the right-angle prism 13d and the low-pass filter 13c are also joined to each other.

With such an arrangement, the image of the subject on the left side in FIG.
Is formed on the image receiving surface 31a. 42 is the solid-state imaging device 31
Is a flexible circuit board 42 to which an electronic component (not shown) for performing the above signal processing is attached, and which is fixedly connected to a distal end portion of the signal cable 43 by soldering. A solid-state image sensor 31 is fixed to the tip side, and the image receiving surface 31a side of the solid-state image sensor 31 is joined to the right-angle prism 13d.

As shown in FIG. 4, the circuit board 42 is bent in a U-shape, and its periphery is covered with a shield tape 44 and an insulating tape 45. An epoxy adhesive 60 is provided in the internal space. Filled and hardened to prevent deformation.

In this manner, the objective optical system 13, the solid-state image sensor 31, the circuit board 42, and the signal cable 43 are integrally formed as a single unit. Through the fixing screw 5
2 fixed.

The circuit board 42 constituting this unit includes:
As described above, the portion hardened by the epoxy adhesive 60 is rigid, but as shown in FIG. 5, the portion between the hardened portion and the portion to which the solid-state imaging device 31 is fixed is provided. In the portion (neck portion) 42a, the circuit board 42 is formed to have a narrow width, and can easily bend in a direction perpendicular to the surface.

Accordingly, even if the insertion portion of the endoscope is strongly looped or the bending portion 1 is fully bent, and the signal cable 43 is pushed and pulled strongly, it is fixed to the connecting tube 12 by the fixing screw 52. The circuit board 42 does not move back and forth or left and right, and the torsional and tilting forces applied to the circuit board 42 from the signal cable 43 are also absorbed by the flexible neck 42a, and the solid-state imaging device 31 and the objective optical system It does not reach 13

FIG. 6 shows a second embodiment of the present invention, in which a space formed around the solid-state imaging device 31 and the circuit board 42 in the distal end of the insertion portion is provided with an elastic silicone adhesive. 70 and the like.

In this manner, the elastic adhesive 70
, The solid-state imaging device 31 and the objective optical system 13 are difficult to move, and the neck 42 a of the circuit board 42 is kept in a flexible state. Therefore, even if the circuit board 42 is slightly moved by the force applied to the signal cable 43. Even, the solid-state imaging device 31
Is difficult to transmit power to.

[0026]

According to the tip of the electronic endoscope of the present invention,
Since the circuit board is connected to the solid-state imaging device in a flexible state, even if the signal cable connected to the circuit board is strongly pushed or pulled, the force is not transmitted to the solid-state imaging device portion, and therefore, In addition, no separation occurs at the joint between the objective optical system and the joint inside the objective optical system.

[Brief description of the drawings]

FIG. 1 is a side sectional view (II sectional view) of a first embodiment.

FIG. 2 is a front view of the first embodiment.

FIG. 3 is a front sectional view (III-III sectional view) of the first embodiment.
It is.

FIG. 4 is a front sectional view (IV-IV sectional view) of the first embodiment.

FIG. 5 is a partial plan view of the first embodiment.

FIG. 6 is a side sectional view of a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Tip main body 12 Connecting cylinder 13 Objective optical system 31 Solid-state image sensor 42 Circuit board 42a Neck 43 Signal cable

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-68130 (JP, A) JP-A-60-221719 (JP, A) JP-A-63-313970 (JP, A) JP-A-4- 357928 (JP, A) JP-A-4-241831 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61B 1/00-1/32 G02B 23/24

Claims (1)

(57) [Claims] An object optical system provided at the distal end of an insertion portion of an endoscope is fixed to a solid-state imaging device, and a signal cable is provided.
At the distal end of the electronic endoscope in which the circuit board connected from the rear and the solid-state imaging device are connected and connected within the distal end of the insertion portion, the circuit board is raised near the signal cable connection portion.
To the insertion section, and to the front of the fixed section.
Part where the circuit board is not fixed to the tip of the insertion part
In, characterized in that by forming a narrow width portion between said signal cable connecting portion and the solid-state imaging device connecting portion of the circuit board, the circuit board is configured to facilitate bending at the thin portion of the width The tip of the electronic endoscope.