JP2006068258A - Electronic endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic endoscope capable of reliably holding an imaging unit at a distal end hard part regardless of outflow or deterioration of an airtight sealant.
An insertion portion extending from an operation portion includes a bending portion that can be bent, and a distal end rigid portion that is disposed at a distal end of the bending portion and an objective optical system is disposed inside the distal end. An image sensor that is fixed to the rear end of the system and forms an image by an objective optical system, a circuit board that controls the operation of the image sensor, and a signal line that connects the image sensor and the circuit board is fixed to each other The imaging unit has elasticity and is press-fitted into a unit holding member mounted in the distal end hard portion.
[Selection] Figure 3

Description

  The present invention relates to an electronic endoscope, and more particularly to a configuration of a distal rigid portion including a rigid imaging unit in which at least an imaging element, a circuit board, and a signal line are fixed to each other.

In a conventional electronic endoscope, the CCD, the circuit board, and the signal line are bonded and fixed together to form an imaging unit in order to prevent the insertion portion from moving, bending, breakage, and failure, and to operate stably. In some cases, the entire imaging unit is disposed in a hole formed in the hard end portion. In order to prevent damage and failure due to intrusion of liquid from the outside, the imaging unit is disposed in the hole with an airtight sealant applied to the outer surface thereof. In this configuration, the gap between the hole and the imaging unit is filled with the hermetic sealant, and the imaging unit is held in the hole by the elasticity and adhesive force of the hermetic sealant.
JP 7-84193 A

  However, in the above-mentioned electronic endoscope, the hermetic sealant dissolves and flows out by washing with the chemical solution after the treatment, or the hermetic sealant is repeatedly introduced and detached from the patient's body in the patient's body. Due to deterioration and a decrease in elasticity and adhesive strength, the imaging unit may not be sufficiently held in the hard end portion.

  In order to solve the above-described problem, in the electronic endoscope of the present invention, the insertion portion extending from the operation portion is disposed at the bending portion that can be bent and the distal end of the bending portion, and the objective optical system is disposed inside the distal end. An imaging element that is fixed to the rear end of the objective optical system and forms an image by the objective optical system, a circuit board that controls the operation of the imaging element, and the imaging element and the circuit A rigid imaging unit in which signal lines connecting the substrate are fixed to each other has elasticity and is press-fitted into a unit holding member mounted in the distal end rigid portion.

In the electronic endoscope of the present invention, the insertion portion extending from the operation portion has a bending portion that can be bent, and a distal end rigid portion disposed at the distal end of the bending portion,
An objective optical system, an image sensor that is fixed to the rear end of the objective optical system and forms an image by the objective optical system, a circuit board that controls the operation of the image sensor, and a signal line that connects the image sensor and the circuit board The rigid imaging units fixed to each other have elasticity and are press-fitted into a unit holding member mounted in the distal end rigid portion.

  The unit holding member has a hollow, substantially frustoconical shape, and the bottom surface is arranged on the operation unit side with respect to the hole portion drilled in the distal end hard portion so that the cross section perpendicular to the axis is a circle having a constant diameter. It is preferable that it is mounted by press-fitting.

  The unit holding member has a substantially cylindrical shape, and can be mounted by press-fitting into a hole portion drilled in the distal end hard portion so that the cross section perpendicular to the axis is a circle having a constant diameter.

  More preferably, the unit holding member is provided with a protrusion protruding outward on the outer periphery thereof.

  The hole is preferably provided with a recess at a position corresponding to the protrusion when the unit holding member is press-fitted, and the protrusion is inserted into the recess to prevent the unit holding member from coming off. be able to.

  The distal end rigid portion can be detached from the curved portion, and the imaging unit can be taken in and out from the rear end portion of the distal end rigid portion.

  A solid-state image sensor can be used as the image sensor.

  According to the present invention, the unit holding member is disposed in the distal end rigid portion, and the imaging unit is retained in the distal end rigid portion, thereby reliably retaining the imaging unit in the distal end rigid portion regardless of the outflow or deterioration of the airtight sealant. An electronic endoscope can be provided.

<First Embodiment>
Hereinafter, a first embodiment according to the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the endoscope 1 according to the first embodiment includes an operation unit 10 for performing suction and bending and an insertion unit 30 to be inserted into a living body.

  The operation unit 10 includes a suction button 11 and a bending operation knob 13 including a left / right bending operation knob 13a and an up / down bending operation knob 13b. When the suction button 11 is pushed in, suction is performed from the forceps channel 32a that opens to the front surface of the distal rigid portion 40, and the affected part is removed of washing water, mucus, and the air in the body cavity.

  The insertion portion 30 includes a flexible tube portion 50, a bending portion 60, and a distal end rigid portion 40 that sheathes the insertion portion 30. As shown in FIG. 2, the distal rigid portion 40 has light distribution lenses 33a1 and 33b1 provided at the distal ends of light guide fibers 33a and 33b (see FIG. 4) for irradiating illumination light to the affected area in front, and an image of the affected area. An objective lens (objective optical system) 71 for forming an image on a CCD (solid-state imaging device) (imaging device) 72 (see FIG. 3), and a forceps channel provided at the tip of a forceps channel tube 32 (see FIG. 4) 32a is arranged. As shown in FIG. 3, the objective lens 71 is fixed with its front surface aligned with the distal end surface 41 of the distal end rigid portion 40. In the present embodiment, the distal end side (front side) refers to the distal end rigid portion 40 side of the endoscope 1, and the rear end side (rear side) refers to the operation portion 10 side of the endoscope 1.

  A biopsy forceps and a brush are inserted into the forceps opening 20 disposed between the insertion portion 30 and the operation portion 10 shown in FIG. The biopsy forceps and the brush inserted into the forceps opening 20 are inserted through a forceps channel tube (not shown) and protrude from the forceps channel 32a of the distal end rigid portion 40.

  As shown in FIG. 3, the bending portion 60 has a plurality of node rings 61a, 61b, 61c, 61d. . . Are connected and arranged with the node ring 61a as a tip side. The two node rings arranged side by side are rotatably connected to each other by rivets 38 and 39 which face each other in the radial direction and are aligned in the center line A direction. In FIG. 3, the light guide fiber, the forceps channel tube, and the bending operation wire are omitted.

  As shown in FIGS. 3 and 4, a pair of bending operation wires 36 a and 36 b are inserted into the bending portion 60, and the distal ends thereof are formed on the inner surface of the hollow cylindrical rear end portion 40 a of the distal end rigid portion 40. It is fixed. Each node ring 61a, 61b, 61c, 61d. . . The node ring assembly formed by connecting the two is covered and protected by a mesh tube 37 braided with a metal wire, and the mesh tube 37 is covered by a coating rubber 31 on the outside. The node ring 61a is detachably fixed to the rear end portion 40a of the distal end hard portion 40 by screws (not shown).

  The operator can bend the bending portion 60 in the left-right direction by turning the left / right bending operation knob 13a, and can bend the bending portion 60 in the up / down direction by turning the up / down bending operation knob 13b. it can. That is, when the operator operates the bending operation knob 13, the bending operation wires 36 a and 36 b inserted into the bending portion 60 and connected to the bending operation knob 13 are pulled or released, and according to the movement of the bending operation wires 36 a and 36 b. Thus, the bending portion 60 is bent. Thus, the operator can bend the bending portion 60 in a desired angle and direction.

  As shown in FIGS. 2 to 4, the distal end rigid portion 40 is a rigid cylindrical member made of, for example, plastic, and includes therein light guide fibers 33 a and 33 b, a forceps channel tube 32, an objective lens 71, and an imaging. A unit 70 and an imaging unit holding member (unit holding member) 80 are disposed.

  The image pickup unit 70 forms an image formed by the objective lens 71, a CCD (solid-state image pickup device) (image pickup device) 72 that converts the image into an electronic signal, a circuit board 73 that controls the operation of the CCD, and the CCD 72 and the circuit board. 73 is a rigid tubular body that is provided with a signal line 74 that connects to the housing 73 and is fixed to each other with an adhesive in a hollow cylindrical metal shield member 70a. The shield member 70a is covered with an insulating member 70b. The imaging unit 70 may be a unit in which the objective lens 71 is fixed to the tip of the CCD 72. In addition to the CCD, a CMOS (Complementary Metal-Oxide Semiconductor) sensor can also be used as the image sensor.

  The imaging unit 70 is accommodated in a hole 45 formed in the distal end rigid portion 40. Thereby, the front-end | tip part which has arrange | positioned CCD72 is arrange | positioned at the rear-end side of the objective lens 71 so that it may become a predetermined positional relationship. The hole 45 includes a small-diameter portion 46, a medium-diameter portion 47, and a large-diameter portion 48 having concentric circular cross-sectional shapes. In the hole 45, an objective lens 71, an imaging unit 70, and an imaging unit holding member 80 in which a fluid-like airtight sealant 90 (for example, epoxy resin or silicone resin) is applied to the outer peripheral surface in advance are introduced.

  The small-diameter portion 46 has an open end surface 46 a communicating with the front end surface 41 of the front end rigid portion 40, and the front end side lens 71 a of the objective lens 71 is attached to the inner surface of the front end surface 46 a through an airtight sealant 90. The objective lens 71 can be accommodated while positioning in the optical axis direction by applying. The medium-diameter portion 47 having an inner diameter larger than the small-diameter portion 46 accommodates the imaging unit 70 while performing axial positioning by applying the tip 70d of the imaging unit 70 to the tip inner surface 47a via the airtight sealant 90. can do. The large-diameter portion 48 having an inner diameter larger than the medium-diameter portion 47 accommodates the imaging unit 70 while positioning the tip 70d of the imaging unit 70 against the inner surface 48a of the tip via an airtight sealant 90 while performing axial positioning. can do.

  The imaging unit holding member 80 is made of an elastic material (for example, silicone rubber or resin), and at least the bottom surface 82 has a diameter that is sufficiently larger than the inner diameter of the large-diameter portion 48 and has an axial length larger than that of the large-diameter portion 48. It has a truncated cone shape. Inside the image pickup unit holding member 80, a holding hole portion 84 penetrating concentrically is formed. When the imaging unit holding member 80 is press-fitted into the large diameter portion 48, the outer peripheral surface (conical surface) 81 of the imaging unit holding member 80 is pressed against and fixed to the inner side surface 48c of the large diameter portion 48 due to its shape and elasticity. Is done.

  Subsequently, introduction of the imaging unit 70 and the objective lens 71 into the distal end rigid portion 40 in the electronic endoscope of the present embodiment will be described. The imaging unit 70 and the objective lens 71 are introduced from the rear end portion 40 a of the distal end rigid portion 40 in a state where the distal end rigid portion 40 is separated from the curved portion 60.

  First, the rear end of the imaging unit 70 and the front end of the objective lens 71 are bonded and fixed in a state where the optical axis of the imaging unit 70 and the axial direction of the imaging unit 70 are matched. In the image pickup unit 70, the CCD 72 and the circuit board 73 are fixed in advance in a predetermined positional relationship, and connected to each other by a signal line 74 are inserted into a shield member 70a having an outer peripheral surface coated with an insulating member 70b and bonded. It is fixed. In this imaging unit 70, the center of the CCD 72 is arranged in the axial direction, the light emitted from the objective lens 71 forms an image on the CCD 72, and the image is used to control the circuit board 73 connected by the signal line 74. Originally converted into an electrical signal.

  On the other hand, the imaging unit holding member 80 is press-fitted into the large-diameter portion 48 while the outer peripheral surface 81 is pressed against the inner side surface 48c. The imaging unit holding member 80 has a tapered shape in which the axial orthogonal cross-sectional diameter of the outer peripheral surface 81 decreases from the bottom surface 82 toward the top surface 83, and the diameter of the bottom surface 82 is smaller than the inner diameter of the large diameter portion 48. Since it is large, it is fixed in the large diameter portion 48 by the elastic force of the imaging unit holding member 80. At this time, the bottom surface 82 extends into the rear end portion 40a.

  Next, the objective lens 71 and the imaging unit 70 in which a predetermined amount of the airtight sealant 90 is applied onto the outer peripheral surface 71b and the insulating member 70b of the objective lens 71, the imaging unit from the bottom 82 side with the objective lens 71 at the head. It is inserted into the holding member 80 and further into the hole 45. The objective lens 71 is positioned in the optical axis direction when the tip lens 71a of the objective lens 71 is brought into contact with the inner surface of the tip surface 46a through the airtight sealant 90.

  On the other hand, the imaging unit 70 is positioned in the axial direction by the tip 70d of the imaging unit 70 being applied to the inner surface 47a of the tip via an airtight sealant 90. At this time, the gap between the objective lens 71 and the small diameter portion 46, the gap between the imaging unit 70 and the medium diameter portion 47, and the gap between the imaging unit holding member 80 and the tip inner surface 48a are filled with the airtight sealant 90. The filling state is maintained due to the adhesiveness of the airtight sealant 90, and the elasticity of the airtight sealant 90 prevents damage and failure due to vibration of the imaging unit 70 and the objective lens 71 even when the insertion portion 30 moves and curves. can do.

  Furthermore, since the outer diameter of the insulating member 70 b is slightly larger than the inner diameter of the holding hole portion 84, when the imaging unit 70 is press-fitted into the imaging unit holding member 80, the imaging unit holding member 80 is elastic and the imaging unit 70 can be held more securely at its axial position. For this reason, even if the airtight sealant 90 flows out or deteriorates, the imaging unit 70 can be reliably held in the distal end rigid portion 40.

Second Embodiment
In the second embodiment, an imaging unit holding member 180 is used instead of the imaging unit holding member 80 of the first embodiment. Here, the same reference numerals are used for the same members as those in the first embodiment, and the description thereof is omitted.
The imaging unit holding member 180 is made of an elastic material (for example, silicone rubber or resin) and has a substantially columnar shape having an outer diameter substantially the same as the inner diameter of the large diameter portion 48. A holding hole 184 that penetrates concentrically is formed inside the imaging unit holding member 180. On the outer peripheral surface 181 of the imaging unit holding member 180, a protruding portion 185 protruding outward is formed in an annular shape at a fixed position on the distal end side in the axial direction of the imaging unit holding member 180. The projecting portion 185 is formed by molding, and the outer diameter thereof is larger than the inner diameter of the large diameter portion 48. When the imaging unit holding member 180 is press-fitted into the large-diameter portion 48, the projection 185 is strongly pressed against the inner side surface 48 c of the large-diameter portion 48, so that the elasticity is fixed to a desired position in the large-diameter portion 48. Can do.

Further, a concave portion 48d is formed on the inner side surface 48c of the large diameter portion 48 at a position corresponding to the projection portion 185 when the outer peripheral surface 181 is press-fitted to the outer peripheral side of the distal end hard portion 40. When the outer peripheral surface 181 is press-fitted into the large-diameter portion 48 and the projection 185 is fitted into the concave portion 48d, the outer peripheral surface 181 can be prevented from coming off in the axial direction.
Other configurations, operations, and effects are the same as those in the first embodiment.

  Although the present invention has been described with reference to the above embodiment, the present invention is not limited to the above embodiment, and can be improved or changed within the scope of the purpose of the improvement or the idea of the present invention.

It is a general-view figure which shows the structure of the whole endoscope. It is a top view of the tip of a tip hard part concerning a 1st embodiment of the present invention. It is a longitudinal cross-sectional view of the front-end | tip rigid part which concerns on 1st Embodiment of this invention, and a curved view. It is sectional drawing along the IV-IV line of FIG. It is a longitudinal cross-sectional view of the front-end | tip rigid part which concerns on 2nd Embodiment of this invention, and a curved view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Endoscope 10 Operation part 20 Forceps port 30 Insertion part 40 Front rigid part 40a Rear end part 41 Front end face 45 Hole part 46 Small diameter part 47 Medium diameter part 48 Large diameter part 60 Curved part 61a Node ring 61b Node ring 61c Node ring 70 Imaging unit 71 Objective lens (objective optical system)
72 CCD (imaging device)
73 Circuit board 74 Signal line 80 Imaging unit holding member (unit holding member)
180 Imaging unit holding member (unit holding member)
A Curve center line (axis)

Claims (8)

The insertion portion extending from the operation portion has a bendable bending portion, and a distal end rigid portion that is disposed at the distal end of the bending portion and the objective optical system is disposed inside the distal end,
An imaging device fixed at the rear end of the objective optical system, on which an image formed by the objective optical system is formed, a circuit board that controls the operation of the imaging element, and a signal line that connects the imaging device and the circuit board An electronic endoscope characterized in that a rigid imaging unit formed by fixing each other has elasticity and is press-fitted into a unit holding member mounted in the distal end rigid portion. The insertion part extending from the operation part has a bendable bending part, and a distal end rigid part arranged at the distal end of the bending part,
An objective optical system, an imaging element fixed to the rear end of the objective optical system, and an image formed by the objective optical system, a circuit board for controlling the operation of the imaging element, and the imaging element and the circuit board. An electronic endoscope, wherein a rigid imaging unit formed by fixing signal lines to be connected to each other has elasticity and is press-fitted into a unit holding member mounted in the distal end rigid portion. The unit holding member has a hollow, substantially truncated cone shape, and the bottom surface of the unit holding member faces the operation portion side with respect to a hole portion formed in the distal end hard portion so that an axial orthogonal cross section is a circle having a constant diameter. The electronic endoscope according to claim 1, wherein the electronic endoscope is mounted by being press-fitted after being placed on the head. The unit holding member has a substantially cylindrical shape, and is mounted by press-fitting into a hole formed in the distal end hard portion so that a cross-section perpendicular to the axis is a circle having a constant diameter. Item 1. The electronic endoscope according to Item 1. The electronic endoscope according to claim 3, wherein the unit holding member includes a protruding portion that protrudes outward on an outer periphery thereof. When the unit holding member is press-fitted into the hole, a concave portion is formed at a position corresponding to the protruding portion, and the protruding portion is fitted into the concave portion to prevent the unit holding member from coming off. The electronic endoscope according to claim 5. The electronic endoscope according to claim 1, wherein the distal rigid portion is detachable from the curved portion, and the imaging unit is taken in and out from a rear end portion of the distal rigid portion. The electronic endoscope according to claim 1, wherein the image sensor is a solid-state image sensor.

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