JP4928974B2 - The tip of the electronic endoscope - Google Patents

Description

  The present invention relates to a distal end portion of an electronic endoscope.

In an electronic endoscope, an objective lens unit with a built-in objective optical system and an image sensor unit with a built-in solid-state image sensor are integrally connected to form an objective / image sensor unit. A unit holding hole for inserting and holding the objective / imaging device unit in the front end body is formed in the front-rear direction, and the objective / imaging device unit is fixed in the unit holding hole with an adhesive. There are many things to have (for example, Patent Document 1).
JP 2003-325445 A

  FIG. 6 illustrates the tip of a conventional electronic endoscope. An objective lens unit 92 containing an objective optical system 91 and an image sensor unit 94 containing a solid-state image sensor 93 are integrally connected. The objective / imaging element unit 95 is configured, and a unit holding hole 97 for inserting and holding the objective / imaging element unit 95 in the front end portion body 96 is formed penetrating in the front-rear direction so that the objective / imaging element unit 95 holds the unit. The hole 97 is fixed with an adhesive 98.

  When a strong epoxy adhesive or the like is used as such an adhesive 98, the object / image sensor unit 95 is not detached from the tip body 96 when the tip body 96 is disassembled and repaired. Cannot be reused, resulting in very large economic and resource losses.

  Accordingly, the objective / imaging device unit 95 is fixed by using a silicon-based adhesive or the like having a lower adhesive strength than an epoxy-based adhesive or the like. The unit 95 can be removed from the tip body 96, and the objective / image sensor unit 95 (at least the solid-state image sensor 93) can be reused.

  However, since the silicon-based adhesive is elastic and has low fluidity, bubbles are included when the adhesive 98 is filled in the space around the objective / imaging element unit 95 in the unit holding hole 97. easy.

  FIG. 7 shows a state of the work of filling the adhesive 98. The adhesive 98 is applied in advance around the objective / imaging element unit 95 and in the unit holding hole 97, and the objective / imaging is performed. The element unit 95 is inserted into the unit holding hole 97.

  However, during such insertion operation, it is inevitable that the objective / imaging device unit 95 swings in the radial direction or the rotational direction with respect to the unit holding hole 97. As a result, the size of the gap between the objective / imaging element unit 95 and the unit holding hole 97 changes variously, so that it is considered that bubbles are mixed in the adhesive 98, and particularly shown in FIG. Thus, it is difficult for the image sensor unit 94 portion having a rectangular cross-sectional shape to prevent the bubbles 99 from being mixed in the adhesive 98.

  If such bubbles 99 are present in the adhesive 98, the bubbles 99 expand or move when the adhesive 98 is heated and dried to form a hole that is connected to the outer surface. There is a risk of hermetic failure causing such a serious failure. Further, the thermally expanded bubble 99 bursts on the outer surface, and irregularly shaped irregularities 100 are formed there as shown in FIG. 9, which may become a reservoir for bacteria and the like. In particular, a silicone adhesive having heat resistance that can be used for autoclave sterilization needs to undergo a heat reaction during drying, and thus such a phenomenon is likely to occur.

  In the present invention, the objective / imaging device unit can be easily removed and collected when disassembling and repairing the tip body, and the objective / imaging device unit is fixed to the unit holding hole of the tip body during assembly work. An object of the present invention is to provide a distal end portion of an electronic endoscope that can be easily assembled without causing any adverse effects even if air bubbles are mixed in the adhesive.

  In order to achieve the above object, the distal end portion of the electronic endoscope of the present invention is configured such that an objective lens unit incorporating an objective optical system and an image sensor unit incorporating a solid-state image sensor are integrally connected to each other. An element unit is configured, and a unit holding hole for inserting and holding the objective / imaging element unit in the front end portion body arranged at the foremost position of the insertion part is formed through the front / rear direction so that the objective / imaging element unit In the distal end portion of the electronic endoscope having a configuration fixed in the unit holding hole with an adhesive, the space around the objective / imaging element unit in the unit holding hole has elasticity in the area except for the vicinity of the distal end. Filled with elastic adhesive, and in the area near the tip, filled with hard adhesive that changes from fluidity to hard by heat treatment, and with hard adhesive, the outer surface of the elastic adhesive and the tip body It is obtained by isolating between.

  The elastic adhesive may be a silicon adhesive, and the hard adhesive may be an epoxy adhesive. And one end of the hard adhesive may be exposed on the outer surface of the tip body, or the hard adhesive may be filled only within a depth range of several mm from the position where the hard adhesive is exposed on the outer surface of the tip body. Good. Moreover, the hard adhesive may be filled after the elastic adhesive is filled.

  According to the present invention, the space around the objective / imaging device unit in the unit holding hole is filled with an elastic adhesive having elasticity in a region excluding the vicinity of the tip, and heat treatment is performed in the region near the tip. Filling with a hard adhesive that changes from fluid to hard and separating the elastic adhesive from the outer surface of the tip body with a hard adhesive, the objective The image sensor unit can be easily removed and collected. In addition, during assembly work, even if bubbles are mixed in the adhesive used to fix the objective / image sensor unit in the unit holding hole of the tip body, it can be removed. Assembling work can be easily performed without adversely affecting the process.

  An objective lens unit incorporating an objective optical system and an image sensor unit incorporating a solid-state image sensor are integrally connected to form an objective / image sensor unit. A tip of an electronic endoscope having a configuration in which a unit holding hole for inserting and holding the objective / imaging element unit is formed in the front-rear direction, and the objective / imaging element unit is fixed in the unit holding hole with an adhesive. In the unit, the space around the objective / imaging device unit in the unit holding hole is filled with a resilient elastic adhesive in the region except for the vicinity of the tip, and the region near the tip is heated from the fluid quality by heat treatment. A hard adhesive that changes to hard is filled, and the elastic adhesive is separated from the outer surface of the tip body by the hard adhesive.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a half sectional view of a distal end portion of an electronic endoscope, and an observation window 3 is disposed on the distal end surface of a distal end portion body 2 connected to the distal end of a flexible insertion portion 1.

  An objective optical system 4 composed of a plurality of lenses is disposed in the back of the observation window 3, and the imaging surface of the solid-state imaging device 5 is disposed at the imaging position of the endoscope observation image by the objective optical system 4. An observation image of the subject in front of the tip (left side in FIG. 1) can be taken.

  The objective lens unit 6 containing the objective optical system 4 and the image pickup device unit 7 containing the solid-state image pickup device 5 are bonded and integrally connected, and thereby the object / image pickup device unit 8 is configured.

  In the image sensor unit 7, a circuit board 9 on which an electronic circuit is mounted is disposed adjacent to the rear of the solid-state image sensor 5, and is imaged by a signal cable 10 that is led from the circuit board 9 into the insertion portion 1 at the rear. Signals, drive signals, etc. are transmitted.

  A unit holding hole 11 for inserting and holding the objective / imaging element unit 8 is formed in the distal end portion body 2 so as to penetrate straight in the front-rear direction. Then, the objective / imaging element unit 8 is disposed in the unit holding hole 11 and fixed thereto with a resilient elastic adhesive 12.

  However, in the region t near the tip of the unit holding hole 11, the unit holding hole 11 is hermetically sealed by filling the unit holding hole 11 with a hard adhesive 13 that changes from fluid to hard due to heat treatment. Thus, the elastic adhesive 12 and the outer surface of the tip body 2 are isolated.

  FIG. 2 shows a process of fixing the objective / imaging element unit 8 in the unit holding hole 11. The imaging element unit 7 including the rectangular solid-state imaging element 5 has a rectangular cross section, and the objective lens unit 6 corresponds to the imaging element unit 7 in the vicinity of the rear end portion connected to the imaging element unit 7. It is formed in a rectangular shape, and the portion closer to it is formed in a circular cross-sectional shape. In the unit holding hole 11, the area 11 a near the tip is circular and the area 11 b behind it is formed in a rectangular cross-sectional shape in accordance with the cross-sectional shape of the objective / imaging element unit 8.

  The elastic adhesive 12 is applied to the entire surface excluding the region t near the tip of the outer peripheral surface of the objective / imaging element unit 8 before being inserted into the unit holding hole 11, and not applied to the unit holding hole 11. . As the elastic adhesive 12, a silicon adhesive or the like is used.

  Then, as shown in FIG. 3, when the objective / imaging device unit 8 is inserted into the unit holding hole 11, the objective in the unit holding hole 11 is removed in the region excluding the region t near the tip in the unit holding hole 11. The space around the image sensor unit 8 is filled with the elastic adhesive 12, and the objective / image sensor unit 8 is fixed in the unit holding hole 11. At that time, bubbles are mixed in the elastic adhesive 12. A portion 12x of the elastic adhesive 12 that protrudes behind the unit holding hole 11 is wiped off.

  As the elastic adhesive 12, it is preferable to use a high heat-resistant adhesive among various silicon-based adhesives. However, since the high-heat-resistant silicon adhesive needs to be reacted by heating, the unit holding hole 11 is filled. And dried in a heated state. Then, bubbles mixed in the elastic adhesive 12 are thermally expanded and moved, and there are some that escape from the front and rear ends of the unit holding hole 11 to the atmosphere.

  When the heat-drying of the elastic adhesive 12 is completed in this way, as shown in FIG. 4, the objective / imaging device unit in the region t near the tip in the unit holding hole 11 with the observation window 3 facing upward is shown. As shown by an arrow A, a hard adhesive 13 that changes from fluidity to hardness is filled in the space between the outer periphery of 8 and the arrow A. As the hard adhesive 13, an epoxy adhesive or the like having a strong adhesive force can be used.

  The hard adhesive 13 such as an epoxy-based adhesive has a fluidity due to a significant decrease in viscosity due to heat treatment, and therefore the objective / imaging element unit 8 in the region t near the tip in the unit holding hole 11. Resilient adhesive that fills the space between the outer periphery of the tube and completely fills it, then becomes dry and hard by heating, and exhibits a smooth surface state without irregularities due to bursting of bubbles. Stronger adhesive strength than 12 mag can be obtained.

  In this way, the hard adhesive 13 is filled at a position where it is exposed on the outer surface of the tip body 2, and the portion is hermetically sealed, and the hard adhesive 13 causes the elastic adhesive 12 and the tip body 2 to be sealed. The outer surface is isolated.

  Therefore, even if bubble rupture or the like occurs on the elastic adhesive 12 side, there is no problem. The length of the region (t) filled with the hard adhesive 13 is about several mm (for example, about 1 to 3 mm, and about 5 mm or less at the maximum), and the cross-sectional shape of the objective lens unit 6 is a circular portion. Only around.

  In this way, the objective / imaging element unit 8 is fixed in the unit holding hole 11 of the tip body 2 with the elastic adhesive 12 and the hard adhesive 13, so that the objective / imaging element unit 8 is made of the elastic adhesive. 12 is fixed in a stable state, and the air tightness to the outside is surely ensured by the hard adhesive 13 to be finished to a smooth surface, and in the work of filling the elastic adhesive 12, it becomes air-mixed. You can work easily without worrying.

  When the tip body 2 is disassembled and repaired, as shown in FIG. 5, the pushing tool 20 or the like is brought into contact with the observation window 3 and pressed hard to break the hard adhesive 13. Since the adhesive 12 originally has an adhesive force that can move the objective / imaging element unit 8 freely, the objective / imaging element unit 8 can be pushed out from the unit holding hole 11 and taken out.

It is side surface half sectional drawing of the front-end | tip part of the electronic endoscope of the Example of this invention. It is a side half sectional view of a state just before the objective / imaging device unit is inserted into the unit holding hole in the assembly process of the distal end portion of the electronic endoscope according to the embodiment of the present invention. It is a side half sectional view showing the state immediately after the objective / imaging device unit is inserted into the unit holding hole in the assembly process of the distal end portion of the electronic endoscope of the embodiment of the present invention. It is a side half sectional view showing the state at the time of being filled with hard adhesive in the assembly process of the tip part of the electronic endoscope of the example of the present invention. It is a side half sectional view showing a state when the objective / imaging device unit is removed from the inside of the unit holding hole when disassembling and repairing the distal end portion of the electronic endoscope of the embodiment of the present invention. It is a side half sectional view of the tip part of the conventional electronic endoscope. It is a side half sectional view of a state just before the objective / imaging device unit is inserted into the unit holding hole in the assembly process of the distal end portion of the conventional electronic endoscope. It is front sectional drawing of the state in which the objective and the image pick-up element unit was inserted in the unit holding hole in the assembly process of the front-end | tip part of the conventional electronic endoscope. It is a partial expanded side surface sectional view of the front-end | tip part of the conventional electronic endoscope.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insertion part 2 Front-end | tip part body 4 Objective optical system 5 Solid-state image sensor 6 Objective lens unit 7 Image sensor unit 8 Objective / image sensor unit 11 Unit holding hole 12 Resilient adhesive 13 Hard adhesive t Area | region (hard adhesion) near a front-end | tip Area filled with agent)

Claims (6)

An objective lens unit incorporating an objective optical system and an image sensor unit incorporating a solid-state image sensor are integrally connected to form an objective / image sensor unit. An electronic endoscope having a configuration in which a unit holding hole for inserting and holding the objective / imaging element unit is formed in the front-rear direction, and the objective / imaging element unit is fixed in the unit holding hole with an adhesive. At the tip of the mirror,
The space around the objective / imaging device unit in the unit holding hole is filled with a resilient elastic adhesive in the region excluding the vicinity of the tip, and in the region near the tip, the fluid is hardened from the fluid quality by heat treatment. A distal end portion of an electronic endoscope, which is filled with a hard adhesive that changes in shape, and the elastic adhesive is separated from the outer surface of the distal end portion main body by the hard adhesive.   The tip portion of an electronic endoscope according to claim 1, wherein the elastic adhesive is a silicon-based adhesive.   The distal end portion of the electronic endoscope according to claim 1 or 2, wherein the hard adhesive is an epoxy adhesive.   The distal end portion of the electronic endoscope according to claim 1, wherein one end of the hard adhesive is exposed on an outer surface of the distal end portion main body.   5. The distal end portion of an electronic endoscope according to claim 1, wherein the hard adhesive is filled only in a range of a depth of several millimeters from a position where the hard adhesive is exposed on the outer surface of the distal end portion main body.   The distal end portion of the electronic endoscope according to claim 1, 2, 3, or 4, wherein the hard adhesive is filled after the elastic adhesive is filled.

Images