JP3637121B2 - Endoscope cover lens fixing part - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope cover lens fixing portion for fixing a cover lens arranged such that a surface is exposed to an outer surface of an endoscope.
[0002]
[Prior art]
The cover lens of the endoscope is fixed to the endoscope so as to be exposed on the outer surface. Therefore, it is fixed using an adhesive having good water resistance so that water or the like does not enter the endoscope from the fixing portion.
[0003]
[Problems to be solved by the invention]
However, each time the endoscope is used, the endoscope is cleaned and disinfected using various chemicals, sterilized by ethylene oxide gas sterilization, or the like.
[0004]
Therefore, the adhesive gradually deteriorates during long-term use, and water-tightness is destroyed and water leakage accidents in which water enters the endoscope or a problem such as lens dropping off may occur.
[0005]
Therefore, an object of the present invention is to provide a cover lens fixing portion of an endoscope having excellent durability, in which the cover lens is not deteriorated even after long-term use.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the cover lens fixing portion of the endoscope according to the present invention is disposed so that the surface is exposed to the outer surface of the endoscope, and the side surface portion is watertightly fixed to the endoscope. In the cover lens fixing portion of the endoscope, a metal film is formed on the side surface of the cover lens by electron shower vapor deposition that performs vacuum deposition together with electron beam irradiation, and the metal film surface is fixed to the metal portion of the endoscope. It is characterized by that.
[0007]
Note that a side surface of the cover lens on which the metal film is formed may be fixed to a metal portion of the endoscope by soldering or brazing, and the cover lens on which the metal film is formed. The side surface may be fixed by an adhesive having good adhesion to metal.
[0008]
Further, the fixing portion may be covered with an adhesive so as not to be exposed on the outer surface, and the metal film may be formed on a part of the side surface of the cover lens.
[0009]
Further, the metal film may be formed continuously on the side surface of the cover lens in the circumferential direction, or the metal film may be formed only on a part of the circumferential direction.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a distal end portion of an insertion portion of an endoscope of a reference example of the present application, and a distal end portion body 1 is formed by coating an outer surface of a metal block 1a with an electrically insulating plastic.
[0011]
Reference numeral 2 denotes an illumination window for radiating illumination light toward a subject, which is watertightly covered by a cover lens 10 made of a concave lens that is exposed on the outer surface, and is illuminated inside the cover lens 10. An exit end face 3a of the light guide fiber bundle 3 for use is arranged. The “cover lens” of the present invention includes a lens having no curvature surface, such as a transparent parallel plate.
[0012]
As shown in FIG. 2, the cover lens 10 has a front half side 10a of a side surface (outer peripheral surface) chamfered to about 45 °, the surface is finished with a grain, and the rear half 10b is irradiated with an electron beam. At the same time, a metal film such as copper, nickel, or chromium is formed by electron shower vapor deposition that performs vacuum vapor deposition.
[0013]
In electron shower vapor deposition, radicals are formed on the vapor deposition surface and molecules are ionically bonded, so the bonding force of the thin film is strong and a much stronger adhesion can be obtained compared to metal films formed by plating or the like. .
[0014]
The metal film surface 10b of the cover lens 10 is fixed to the metal block portion 1a of the tip body 1 in a watertight manner by soldering or silver brazing, so that the cover lens 10 is attached to the tip body 1. And mechanically strong.
[0015]
In the groove formed between the chamfered surface 10a on the front side of the cover lens 10 and the plastic block portion 1b of the distal end portion main body 1, an adhesive 4 such as epoxy or silicon that has water resistance is provided. It is filled so that the metal part inside it does not directly touch the chemical solution. Therefore, even if cleaning and disinfection is repeated, corrosion of the internal metal portion is unlikely to occur.
[0016]
Note that the metal film surface 10b of the cover lens 10 may be fixed to the metal block portion 1a of the tip body 1 with an adhesive. Even in such a case, an adhesive having a strong adhesiveness to metal can be used, so that a much stronger adhesive force can be obtained as compared with the case where the glass surface is bonded.
[0017]
3 and 4 show an example in which the present invention is applied to an observation objective optical system. A cover lens 20 of the objective optical system is fitted in an observation window 6 formed in the distal end main body 1.
[0018]
As shown in FIG. 4, the cover lens 20 has a metal film formed by electron shower vapor deposition only on the inclined surface 20c between the front small diameter portion 20a and the rear large diameter portion 20b on the side surface (outer peripheral surface). Is formed. Therefore, adverse effects on the observed image due to irregular reflection at the metal film portion are minimized.
[0019]
Then, the metal film surface 20c portion of the cover lens 20 is made watertight by caulking and soldering or silver brazing on the tip portion of the metal lens frame 7 in which an objective lens group (not shown) is fitted and supported. It is fixed.
[0020]
4 is an epoxy-based or silicon-based adhesive filled so as to cover the fixing portion so that the fixing portion is not exposed to the outer surface. Note that, similarly to the above-described reference example , the metal film surface 20c may be fixed to the lens frame 7 by adhesion.
[0021]
In the form of implementation described above, to form a metal film continuously in the circumferential direction of the cover lens side. This is effective in maintaining the best watertightness by continuously bonding to the lens frame by soldering, silver brazing, and bonding in the circumferential direction.
[0022]
However, as long as sufficient water-tightness can be maintained in other portions, the metal film may be provided only in a part of the circumferential direction of the cover lens side surface, or may be provided intermittently. By doing so, it is possible to effectively reduce the metal film portion that can cause irregular reflection.
[0023]
Note that the present invention can be applied not only to the distal end of the insertion portion of the endoscope but also to other portions (for example, an eyepiece).
[0024]
【The invention's effect】
According to the present invention, the metal film is formed on the side surface of the cover lens by electron shower vapor deposition, and the surface is fixed to the metal part of the endoscope, so that it is firmly mechanically fixed by soldering or brazing. In addition, since an adhesive that adheres well to a metal can be fixed, the fixed state of the lens hardly deteriorates even after long-term use, and excellent durability can be obtained.
[Brief description of the drawings]
FIG. 1 is a side view of a periphery of an illumination window according to a reference example of the present invention.
FIG. 2 is a perspective view of an illumination window cover lens according to a reference example of the present invention.
FIG. 3 is a side view around the observation window according to the embodiment of the present invention.
FIG. 4 is a perspective view of an observation window cover lens according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tip part main body 1a Metal block part 7 Mirror frame 10, 20 Cover lens 10b, 20c Metal film surface

Claims (6)

Surfaces are arranged so as to be exposed on the outer surface of the endoscope, the cover lens fixing portion of the endoscope which is secured in a watertight with respect to the endoscope,
The cover lens has a narrow-diameter portion on the front side, a large-diameter portion on the rear side, and a slope portion connecting the outer peripheral surface of the thin-diameter portion and the outer peripheral surface of the large-diameter portion in an oblique direction with respect to the axis. And forming a metal film only on the slope portion , and fixing the metal film surface portion to the metal portion of the endoscope. The cover lens fixing part of the endoscope according to claim 1 , wherein the metal film is formed by electron shower vapor deposition that performs vacuum vapor deposition together with electron beam irradiation . The metal film surface portion, soldering, brazing or cover lens fixing portion of the endoscope of any one the claims 1 or 2 wherein is secured by the caulking of the adhesion to the metal portion of the endoscope. The cover lens fixing portion of the endoscope according to claim 2 or 3, wherein the fixing portion is covered with an adhesive so as not to be exposed on an outer surface. The cover lens fixing portion for an endoscope according to claim 1, 2, 3, or 4 , wherein the metal film is continuously formed on the slope portion in the circumferential direction. The cover lens fixing portion of the endoscope according to claim 1, 2, 3, or 4 , wherein the metal film is formed on the slope portion only in a part of the circumferential direction.

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