JPS61135630A - Exterior parts of endoscope - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an exterior component for an endoscope or the like that can be lightweight and has good abrasion resistance and disinfection resistance.

[Technical Background of the Invention and Problems Therewith] In recent years, endoscopes have been widely used which enable diagnosis or inspection of the inside of a body cavity by inserting an elongated insertion section. This endoscope has a bendable flexible insertion section,
A flexible endoscope that can be inserted into a curved path from the oral cavity, etc., and a rigid endoscope that can be inserted straight into the target area through a puncture hole formed in the abdominal wall, etc. There is a Jl mirror.

By the way, the exterior parts used for the exterior parts of rigid endoscopes and the like are particularly required to have anti-sterilization properties due to the special nature of their uses. Disinfection resistance here refers to resistance to steam sterilization, and the disinfection conditions are extremely severe: 135° C. and 2.2 atmospheres of water vapor. There is also a need for resistance to abrasions that may occur from contact with the device during use or disinfection.

Although the above-mentioned disinfection method is a perfect method for sterilizing medical instruments, it has not been adopted as a method for disinfecting rigid endoscopes. This is because the dominant endoscope could not withstand such disinfection methods. That is, conventionally,
The above exterior parts are made of nickel/copper alloy with a three-layer plating of copper, nickel, and chromium, and the exterior parts treated in this way have a surface hardness of about Hi800. This is because, although it exhibits good abrasion resistance, the plating layer peels off when disinfected using the above-mentioned sterilization method.

On the other hand, as for manufacturing problems, since the above-mentioned plating treatment is performed by a wet plating process, there are inevitably problems with pollution such as plating waste liquid, and the manufacturing cost is also high.

Recently, as one of the ways to solve the above problems,
Exterior parts that are made of austenitic stainless steel, which has good corrosion resistance, and copper-nickel alloys such as Mone Metal, which contains about 67% nickel, are being used without plating. Such exterior parts are cheaper than plated parts, and those made of austenitic stainless steel have sufficient disinfection resistance.

On the other hand, copper-nickel alloys such as Mone Metal cannot withstand steam sterilization due to discoloration of the surface. The problem is that the hardness of the material is only about 30%, and scratches easily occur. If the product gets scratched during use, it will not only impair its clean appearance, but also become susceptible to foreign matter, dirt, etc., which will significantly shorten the product life.

In terms of scratch resistance, alloy steel such as nickel-chromium steel or martensitic stainless steel is used, and it is hardened and tempered) -1r#550
Although it is possible to obtain higher hardness and solve the problem of scratches,
These alloys have poor corrosion resistance and cannot withstand the above disinfection conditions.

Furthermore, for exterior parts using the materials mentioned above,
In order to satisfy the strength required for the part, there are restrictions on dimensions such as the diameter and wall thickness of the part, and there are limits to the weight reduction of the part and the degree of freedom in design.

As described above, several problems remain with the exterior components of endoscopes and the like currently in use.

[Object of the Invention] The present invention has been made in view of these circumstances, and provides an exterior component for an endoscope or the like that is lightweight and has excellent abrasion resistance and disinfection resistance. The purpose is to

[Summary of the Invention] In order to achieve the above object, the present invention provides a material for the exterior parts of endoscopes etc. by using Ni-Cr-Mo-W alloy or Nl-Mo-Fe alloy. The aim is to reduce the weight of the material and improve scratch resistance and disinfection resistance.

[Embodiments of the invention] Hereinafter, the present invention will be specifically described with reference to the drawings.

FIG. 1 shows each component product that makes up a resect scope having exterior parts, and FIG. 2 shows a resect scope assembled with the component products shown in FIG. 1.

A resectoscope configured as an example of an exterior component in the present invention includes a telescope (optical viewing tube) 2 having an elongated insertion portion 1 as shown in FIG.
As shown in FIG. 2, a working element 4 has a fixed rear end of an electrode 3 and can move the electrode 3 back and forth to remove an enlarged prostate, and a sheath is inserted into the urethra and the working element 4 is passed through. It consists of 5.

Thus, the working element 4 is set to a state where it can be used as a resect scope 6 as shown in FIG. It is now possible to do so.

The optical viewing tube 2 consists of a rigid and elongated insertion section 1 and a large diameter eyepiece section 7 connected to the rear end of the insertion section 1. The light guide is inserted through the objective optical system that forms an image of the object and an image transmission means that transmits the optical image to the eyepiece 7 side, so that it can be observed from behind the eyepiece 7. . In addition, on the side of the eyepiece part 7,
A light guide base 8 is provided to which a light guide cable for guiding illumination light from a light source device (not shown) can be attached.

The sheath 5 also has a sheath insertion section 9 inserted into the urethra.
and a sheath main body 10 to which the proximal end of the sheath insertion section 9 is connected, and the working element 4 is fitted into the open proximal (rear) end of the sheath main body 10. A working element connecting portion 11 is formed to allow attachment. Further, a finger hook 12, 12 is provided vertically protruding approximately at the center of the side portion of the sheath main body portion 10. A beak 13 made of an insulating material such as epoxy resin or ceramics is attached to the tip of the sheath insertion portion 9.

On the other hand, the working element 4 includes a fixing part 15 in which the proximal part of the scope insertion pipe 14 through which the insertion part 1 of the optical viewing tube 2 is inserted is fixed by passing through a through hole, and It is comprised of a surrounding part (slider) 16 that is fitted onto the outside so that it can slide and move near the rear end.

In parallel with the scope insertion pipe 14 through which the insertion section 1 of the optical viewing tube 2 is inserted, an electrode insertion pipe 17 through which the resection electrode 3 is inserted is fitted and fixed into a through hole provided in the fixing section 15. The proximal end of the electrode 3 inserted into the electrode insertion pipe 17 is fixed to the electrode connection part 18 of the sliding part 16, and at this electrode connection part 18, a high frequency current from a power supply device (not shown) is applied to the electrode 3. It is configured such that the supplied and exposed electrode tip 3A can cut off the affected area or the like that comes into contact with it by high-frequency heating. The electrode 113 is separated into two parallel lines near the tip, and the tip side thereof is bent downward, for example, to form an electrode tip portion 3A connected to each other in a semicircular shape.

The fixing part 15 that is externally fixed to the scope insertion pipe 14 has a tapered surface on the side near the approximately cylindrical front end so that it can be easily fitted into the working element connecting part 11 of the sheath 5. It is strained. However, the fixed part 1
The scope insertion pipe 14 passes through the through hole 5 and is exposed.
A hollow cylindrical guide shaft 20 is provided, which is substantially parallel to the scope, extends rearward, and has an end fixed to the scope connecting portion 19.

The sliding part 16 is fitted between the fixed part 15 and the scope connecting part 19 in the guide shaft 20, such as by inserting the guide shaft 20 into a hole provided in the sliding part 16. The surrounding portion 16 is configured to be able to slide and move in the axial direction of the guide shaft 20. This guide shaft 20 has a long notch formed on both opposing sides along its cylindrical axis and communicating with the center thereof.
A rod-shaped spring pressing member 22 is normally urged to move rearward by a coil spring 21 housed in a hollow portion of a guide shaft 20 whose front end is fixed by a fixing portion 15 and whose front end is closed. It passes through notches formed on both sides and is fixed at sliding portions 16 on both sides of the notches. Note that a ring-shaped finger rest 23 is provided protruding from the lower end of the sliding portion 16.

By the way, in the present invention, the resectoscope 6
, its component parts, for example, the insertion part 1 of the optical viewing tube 2
．． Scope insertion pipe 14 of working element 4.
and electrode insertion pipe 17. .

In order to impart disinfection resistance and abrasion resistance to the exterior parts forming the sheath insertion part 9 of the sheath 5, the material of each of the exterior parts is chromium (Or > 15-1).
7wt%, molybdenum (Mo) 15-17wt%,
Tungsten (W) 3-5 wt%.

A metal consisting of 0.02 wt% carbon (C) and the balance nickel (Ni) (for example, Mitsubishi Metals 11MA Plasthard C,
MA Plast Hard S [trade name]), or molybdenum (Mo) 26-3Qwt%, iron (Fe) 2wt% or less, silicon (Si) 0.1wt% or less, carbon (C) 0.
It is formed of a metal consisting of the remainder of 02Ni (for example, MA Plast Hard B-2 [trade name] manufactured by Mitsubishi Metals). The former is
Hastelloy C is well known as a corrosion-resistant alloy, and the latter is very similar in composition to Hastelloy B, but the above alloy significantly improves both strength and hardness by applying special heat treatment after cold opening. It is significantly different from corrosion-resistant alloys such as Hastelloy C and Hastelloy B.

In other words, when applying this material to the sheath insertion portion 9 of the sheath, for example, it is formed into a pipe shape by drawing from an ingot of a predetermined composition, and then subjected to special heat treatment to create a high-strength, high-hardness exterior component. can be obtained.

Table 1 shows cold-drawn austenitic stainless steel 5t JS304, the above-mentioned Ni-Or-Mo-W alloy and Ni-
Comparative data on tensile strength and height of Mo-Fe alloys are presented.

In this way, the Ni-Cr-Mo-W applied in the present invention
The alloy, Ni-Mo-Fe alloy has higher strength compared to 5US304, IIJ! It shows high values in both degrees, and conventionally,
The diameter and wall thickness of parts required to meet the deformation resistance required for product use can be significantly reduced, and as a result, the diameter and weight can be reduced.

Next, the present inventors determined that the hardness of this alloy is 5US, which is work hardened.
Noting that it is higher than 304, an abrasion resistance test was conducted to confirm the degree of abrasion resistance required for exterior parts.

As a test method, the sheath 5 has a shape approximately equivalent to the sheath insertion portion 9, that is, a diameter of 10 cm, a wall thickness of 0.35 cm, and a length of 300 cm.
A test piece of mm in diameter was prepared, #1000 emery paper was pressed against the surface of the test piece with a load of 100 g, and the material was rotated at 20 Orpm for 5 seconds, and then the appearance of scratches on the surface was observed.

Two types of samples were used as comparative materials: 5tJS304 and a Ni-C11 alloy plated with three layers of Cu-Ni-Or. The results are shown in Table 2.

Table 2 In this way, Ni-Cr-Mo-W alloy and Ni-
The Mo-Fe alloy showed better scuff resistance than the work-hardened 5US304 test piece, although it was inferior to the Ni-Cu alloy test piece with 311 plating. It was confirmed that the material was sufficiently durable for use as an endoscope exterior component.

Furthermore, in order to confirm the disinfection resistance of the above two types of alloys,
Test pieces having the same shape as the test pieces used in the abrasion resistance test were used and held in water vapor at 135° C. and 2.2 atm for 500 minutes under steam sterilization and disinfection conditions.

Although the above conditions were the most severe among disinfection methods, none of the test pieces showed any discoloration or rust after the test.

From the above series of experimental results, it was confirmed that the exterior parts of endoscopes, etc. of the present invention not only can be made lighter due to their strength advantages, but also have excellent scratch resistance and disinfection resistance.

It goes without saying that the present invention is applicable not only to the resectoscope 6 but also to exterior components of other rigid endoscopes such as the cystourethroscope, the vI lumenoscope, and the Kan III.

Furthermore, although this embodiment has been described using a rigid endoscope, it goes without saying that the present invention is not limited to rigid endoscopes and can also be applied to metal exterior parts of flexible endoscopes.

[Effects of the Invention] As explained above, according to the present invention, it is possible to reduce the weight of exterior parts such as endoscopes, and to significantly improve scratch resistance and disinfection resistance. It has the effect of prolonging the lifespan.

[Brief explanation of the drawing]

Fig. 1 is a side view showing a resectoscope according to an embodiment of the present invention broken down into its constituent products, and Fig. 2 is a side view showing the resectoscope set to a usable state by combining the constituent products. It is a diagram. Figure 1

Claims (3)

[Claims] (1) Ni-Cr-Mo-W alloy or Ni-Mo-Fe
An exterior part for an endoscope, etc., characterized by being formed from an alloy. (2) The above Ni-Cr-Mo-W alloy has Cr15 to
17wt%, Mo15-17wt%, W3-5wt%,
The exterior component for an endoscope or the like according to claim 1, characterized in that C is 0.02 wt% or less and the remainder is Ni. (3) The above Ni-Mo-Fe alloy has Mo26-30
wt%, Fe2wt% or less, Si0.1wt% or less, C
The exterior component for an endoscope or the like according to claim 1, wherein the remaining Ni is 0.02 wt% or less.