JP2004129719A - Flexible tube for endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make the strand of the net-like tube of an endoscope hard to rust. <P>SOLUTION: A flexible tube for the endoscope is provided with the net-like tube 38 constituted by using a strand bundle 42 composed by arranging at least two or more strands and a jacket 39 put on the net-like tube 38 and composed of a high molecular material. The strand bundle 42 is composed by combining one or more strands 40 composed of an electric insulating material and a strand 41 composed of a conductive metal material. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a flexible tube used for an endoscope.
[0002]
[Prior art]
In medical endoscopes, it is indispensable to clean and sterilize the used endoscope in particular. Therefore, recently, autoclave sterilization (high-temperature and high-pressure steam sterilization), which can be used immediately after sterilization and disinfection without a complicated operation as a means for sterilizing and disinfecting the endoscope and has a low running cost, has been increasingly used.
[0003]
However, the sterilization environment by autoclave sterilization is very severe for an endoscope. In view of this, Japanese Patent Application Laid-Open No. 2002-17658 (Patent Document 1) proposes an endoscope that can suppress deterioration of bending rigidity of a flexible tube portion such as an insertion portion when exposed to the high temperature of autoclave sterilization. are doing.
[0004]
[Patent Document 1]
JP-A-2002-17658 (pages 4 to 5, FIG. 2)
[0005]
[Problems to be solved by the invention]
Generally, high-pressure high-temperature steam during autoclave sterilization slightly permeates a polymer material such as rubber or plastic or an adhesive, which is a member constituting an endoscope. As in the endoscope disclosed in Japanese Patent Application Laid-Open No. 2002-17658, which is capable of performing autoclave sterilization, a small amount of water vapor during autoclave sterilization is applied to the flexible tube sheath made of a polymer material. Through the metal parts, such as a mesh tube forming a flexible tube. The invading water vapor has been a factor that causes metal parts such as a mesh tube to rust.
[0006]
Since the wires constituting the mesh tube are very thin, even a slight rust may cause wire breakage. Further, the rust powder is transferred to various metal parts inside the endoscope and induces rust, which is a secondary factor causing abnormalities of various functions. Further, if the mesh tube breaks, the performance of the flexible tube, such as flexibility and elasticity, may be reduced.
[0007]
The present invention has been made in view of the above-mentioned problem, and an object of the present invention is to provide an endoscope in which a wire of a mesh tube is hardly rusted.
[0008]
[Means for Solving the Problems]
The present invention relates to a flexible tube for an endoscope, comprising: a reticulated tube formed by using a wire bundle formed by bundling at least two or more wires, and a sheath covered with the reticulated tube and made of a polymer material. In the flexible tube for an endoscope, the element bundle is constituted by combining an element wire made of one or more electrically insulating materials and an element wire made of a conductive metal material. is there.
According to the present invention, since the strand bundle is made of a combination of the conductive metal material and the electrically insulating material, it becomes difficult for electricity to flow between the conductive metal material strands. The reaction can be suppressed, and rust of the mesh tube caused by repeated autoclave sterilization can be prevented.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view schematically showing an entire configuration including an endoscope device and peripheral devices, FIG. 2 is an explanatory view of a flexible tube of an endoscope insertion portion shown in FIG. 1, and FIG. 3 is the flexible tube. It is a perspective view which expands and shows the braided tube of FIG.
[0010]
As shown in FIG. 1, an endoscope apparatus 1 includes an endoscope 2 having an imaging unit (not shown) and a light guide removably connected to the endoscope 2 and provided on the endoscope 2. A light source device 3 for supplying illumination light to the endoscope 2 is connected to the endoscope 2 via a signal cable 4 to control the imaging means of the endoscope 2 and to process a signal obtained from the imaging means. A video processor 5 that outputs a standard video signal, and a monitor 6 that receives the video signal from the video processor 5 and displays an endoscopic image.
[0011]
The endoscope 2 is washed after being used for observation and treatment, and thereafter can be sterilized by autoclave sterilization (high-temperature high-pressure steam sterilization).
[0012]
The endoscope 2 has a flexible elongated insertion portion 7, an operation portion 8 provided on the proximal end side of the insertion portion 7, and has flexibility extending from a side portion of the operation portion 8. A universal cord 9, a connector 10 provided at an end of the universal cord 9 and detachably connectable to the light source device 3, and a connector 10 provided at a side of the connector 10 and connectable to the video processor 5. The signal cable 4 is mainly constituted by a detachable electrical connector section 11.
[0013]
A connecting portion between the insertion portion 7 and the operation portion 8 is provided with an insertion portion side stopping member 12 having an elastic member for preventing a sharp bend of the connection portion. An operation portion side stopper member 13 is provided at a connection portion with the universal cord 9, and a connector portion side stopper member 14 is provided at a connection portion between the universal cord 9 and the connector portion 10.
[0014]
The insertion portion 7 has a flexible tube portion 15 having flexibility, a bending portion 16 that can be bent by a bending operation of the operation portion 8 provided on the distal end side of the flexible tube portion 15, And an end portion 17 provided with an observation optical system, an illumination optical system, and the like (not shown).
[0015]
The operation unit 8 includes an air supply / water supply operation button 21 for operating an air supply operation and a water supply operation, a suction operation button 22 for operating a suction operation, and a bending operation knob for performing a bending operation of the bending unit 16. 23, a plurality of remote switches 24 for remotely operating the video processor 5, and a treatment tool insertion port 25 which is an opening communicating with a treatment tool channel formed in the endoscope 2.
[0016]
The distal end portion 17 includes a liquid supply port (not shown) and a gas supply / water supply nozzle (not shown) for ejecting a cleaning liquid or gas toward an observation window of an observation optical system (not shown) by a gas supply operation or a water supply operation. A suction port (not shown), which is an opening on the distal end side of a treatment tool channel (not shown), through which the disposed treatment tool is inserted or a liquid inside the body cavity is sucked, is provided.
[0017]
The connector section 10 has a gas supply base 26 detachably connected to a gas supply source (not shown) built in the light source device 3 and a water supply tank detachably connected to a water supply tank 27 serving as a liquid supply source. Water is supplied from the pressure base 28 and the liquid supply base 29, a suction base 30 connected to a suction source (not shown) for performing suction from the suction port of the distal end portion 17, and the liquid supply port of the distal end portion 17. And an inlet 31 connected to a water supply means (not shown). The connector section 10 is provided with a ground terminal base 32 for returning the leakage current to the high-frequency processing device when a high-frequency leakage current occurs in the endoscope when performing high-frequency processing or the like.
[0018]
The electric connector section 11 is provided with a ventilation section (not shown) for communicating the inside and the outside of the endoscope 2 with each other. Further, a waterproof cap 33 with a pressure adjusting valve can be detachably connected to the electric connector section 11, and the waterproof cap 33 is provided with a pressure adjusting valve (not shown).
[0019]
Next, the structure of the flexible tube 15 in the endoscope 2 will be described. As shown in FIG. 2, the flexible tube portion 15 includes, in order from the inside, a spiral tube 37 in which a metal strip is spirally wound, and a net-like tube 38 formed in a net shape to cover the outside of the spiral tube 37. And a resin outer skin 39 that covers the outside of the mesh tube 38.
[0020]
For the outer cover 39, a resin that can withstand high-temperature and high-pressure steam, such as an ester-based, styrene-based, olefin-based, or amide-based thermoplastic elastomer, is used alone or as a blend. The outer cover 39 is black, and an index 43 as a guide at the time of insertion is printed in yellow or white on the surface thereof. The color of the indicator 43 may be another color.
[0021]
The mesh tube 38 is formed by using a wire bundle 42 formed by bundling, for example, a polyamide fiber wire 40 having electrical insulation and water absorption and a SUS (stainless steel) wire 41 as a conductive metal material. It is constructed by weaving or weaving in a net shape. Here, the term “bundle” has a broad meaning including the meaning of combining element wires.
[0022]
In particular, the mesh tube 38 of the present embodiment is configured using a strand bundle 42 having a configuration in which the polyamide fiber strands 40 and the SUS strands 41 are arranged alternately and in parallel as shown in an enlarged manner in FIG. are doing. The polyamide fiber strand 40 is thicker than the SUS strand 41.
[0023]
The strand bundle 42 is not limited to one in which the two strands 40 and 41 are alternately arranged one by one, but may have an arrangement configuration in which the ratio of the polyamide-based strands 40 is larger. In addition, it is preferable that the two wires 40 and 41 are arranged in parallel. However, not only this arrangement format but also another arrangement such as twisting a plurality of wires may be used. Further, the strand may be enclosed by another string-shaped object.
[0024]
There is no particular limitation on the braiding method such as the method of knitting or weaving using the wire bundle 42, but a method of obtaining a thin and strong net-like tube 38 is preferable.
[0025]
Further, as the material of the electrically insulative strand, other synthetic resin such as fluorine, silk, octopus, other non-metallic materials other than polyamide may be used, or a plurality of arbitrarily selected from these materials. A composite material formed of a material may be used. As the material of the conductive strand, a metal material other than SUS, such as copper, brass, tungsten, and iron, may be another conductive material, or a composite material formed of a plurality of materials arbitrarily selected from these materials. May be used.
[0026]
As shown in FIG. 2, the helical tube 37 of the flexible tube portion 15 has a structure in which the strips are overlapped twice so that the winding directions are reversed. In addition, the overlapping length of the spiral tube 37 may be the entire length of the flexible tube portion 15 or only a part thereof, or the spiral tube 37 may be wound three times. Any of these may have a structure suitable for the use and performance of the flexible tube portion 15.
[0027]
The endoscope 2 is washed after being used for observation and treatment, and then sterilized by autoclave sterilization (high-temperature high-pressure steam sterilization). When the endoscope 2 is subjected to autoclave sterilization (high-temperature, high-pressure steam sterilization), a sterilization storage case (hereinafter, storage case) 34 for storing the endoscope 2 is used. The storage case 34 includes a tray 35 for storing the endoscope 2 and a back cover member 36 of the tray 35. The tray 35 and the back cover member 36 are provided with a plurality of vents (not shown) so that steam can pass through the holes during autoclave sterilization (high-temperature high-pressure steam sterilization).
[0028]
A regulating portion (not shown) is formed on the tray 35 corresponding to the shape in which the endoscope 2 is arranged. The restricting portions are provided so that respective portions of the endoscope 2 are accommodated in predetermined positions of the storage case 34.
[0029]
As described above, typical conditions for high-temperature and high-pressure steam sterilization include approval by the American National Standards Institute and US Vascular Standard ANSI / AAMI ST37-1992 issued by the Medical Device Development Association, prevacuum type, sterilization process at 132 ° C. for 4 minutes, and gravity type. The sterilization process is performed at 132 ° C. for 10 minutes.
[0030]
The temperature conditions in the high-temperature and high-pressure steam sterilization during the sterilization step vary depending on the type of the high-temperature and high-pressure steam sterilizer and the time of the sterilization step, but are generally set in a range of about 115 ° C. to 138 ° C. Some sterilizers can be set to about 142 ° C. The time condition varies depending on the temperature condition of the sterilization process, but is generally set to about 3 to 60 minutes. Further, depending on the type of the sterilization apparatus, there is also one that can be set to about 100 minutes.
[0031]
The pressure in the sterilization chamber in the high-temperature and high-pressure steam process is generally set to about +0.2 MPa with respect to the atmospheric pressure.
The general pre-vacuum type high-temperature and high-pressure steam sterilization process involves a pre-vacuum process in which the sterilization chamber containing the equipment to be sterilized is depressurized before the sterilization process, and after this process, high-pressure high-temperature steam is sent into the sterilization room to sterilize A sterilization step of performing The pre-vacuum step is a step for allowing steam to penetrate into the details of the equipment to be sterilized during the subsequent sterilization step. By reducing the pressure in the sterilization chamber, high-pressure high-temperature steam is distributed throughout the equipment to be sterilized. The pressure in the sterilization chamber in this pre-vacuum step is generally set to about -0.07 MPa to -0.09 MPa with respect to the atmospheric pressure.
[0032]
Some methods include a drying step in which the sterilization chamber is again depressurized after the sterilization step in order to dry the equipment to be sterilized after the sterilization. In this drying step, the pressure in the sterilization chamber is reduced to remove steam from the sterilization chamber, thereby promoting the drying of the equipment to be sterilized in the sterilization chamber. The pressure in the sterilization chamber in this drying step is generally set to about -0.07 to -0.09 MPa with respect to the atmospheric pressure.
[0033]
When the endoscope 2 is subjected to autoclave sterilization (high-temperature and high-pressure steam sterilization), the endoscope 2 is mounted in a state where the waterproof cap 33 with the pressure adjusting valve is attached to the electric connector unit 11. In this state, the pressure adjusting valve (not shown) of the waterproof cap 33 is closed, the vent is closed by the waterproof cap 33, and the inside of the endoscope 2 is hermetically sealed from the outside.
[0034]
Further, in the case of a sterilization method having a pre-vacuum step, when the pressure inside the sterilization chamber decreases in the pre-vacuum step and the pressure becomes lower outside the endoscope 2 than inside the endoscope 2, the above-mentioned pressure is reduced. The regulating valve is opened, and the inside and the outside of the endoscope 2 communicate with each other through the ventilation port to prevent a large pressure difference between the inside of the endoscope 2 and the pressure in the sterilization chamber. Thus, the endoscope 2 is not damaged by a pressure difference between the inside and the outside.
[0035]
In the sterilization step, when a pressure difference is generated in the sterilization chamber such that the pressure inside the endoscope 2 becomes higher than that inside the endoscope 2, the pressure regulating valve closes. As a result, high-pressure and high-temperature steam does not actively enter the endoscope 2 through the waterproof cap 33 and the ventilation hole.
[0036]
However, the high-temperature and high-pressure steam is an O-ring made of fluorine rubber, silicon rubber, or the like, which is a sealing means provided at the outer skin of the flexible tube made of a polymer material or at a connection portion of the outer body of the endoscope 2. Infiltrate the inside gradually from the like. Since the pressure applied in the pre-vacuum process and the pressure applied in the sterilization process are added to the exterior body of the endoscope 2, a state is created in which pressure from the outside toward the inside is generated. Intrusion is promoted.
[0037]
Further, when a method including a decompression step is adopted after the sterilization step, a pressure difference occurs such that the pressure in the sterilization chamber is reduced in the decompression step and the pressure outside the endoscope 2 is lower than that inside the endoscope 2. At about the same time, the pressure regulating valve is opened, and the inside and the outside of the endoscope 2 communicate with each other through the ventilation port to prevent a large pressure difference between the inside of the endoscope 2 and the pressure in the sterilization chamber. To For this reason, the endoscope 2 is not damaged by a pressure difference between the inside and the outside.
[0038]
When the decompression step is completed and the inside of the sterilization chamber is pressurized to generate a pressure difference such that the pressure is higher outside the endoscope 2 than inside the endoscope 2, the pressure regulating valve is closed.
[0039]
When all the steps of the high-temperature and high-pressure steam sterilization are completed, the outer body of the endoscope 2 is in a state where the pressure from the outside toward the inside is generated by the reduced pressure in the pressure reducing step.
[0040]
When all the steps of the high-temperature and high-pressure steam sterilization described above are completed, the outer body of the endoscope 2 is in a state where the pressure from the outside to the inside is generated by the reduced pressure in the decompression step.
[0041]
When the waterproof cap 33 is removed from the electrical connector section 11, the inside and the outside of the endoscope 2 communicate with each other through the ventilation port, and the inside of the endoscope 2 is set to the atmospheric pressure. The load caused by the pressure that caused the body disappears. Also at this time, there is an opportunity for steam to enter the inside of the endoscope 2.
[0042]
As described above, since the endoscope 2 is subjected to autoclave sterilization after being cleaned after use, water vapor may permeate through the outer cover 39 and reach the mesh tube 38 of the flexible tube portion 15.
[0043]
However, since the SUS strand 41 is thinner than the polyamide fiber strand 40 constituting the mesh tube 38, the gap between the SUS strands 41 is widened even in the portion where the strand bundles 42 overlap, and the inside and outside of the gap A difference in ion concentration hardly occurs. Thereby, the anode / cathode reaction can be suppressed, and rust caused by repeating autoclave sterilization hardly occurs.
[0044]
In addition, since the conductive SUS wires 41 are not adjacent to each other and are insulated from each other, the flow of electrons in the conductive material required for the rust anode / cathode reaction is suppressed. The generation of rust can be suppressed.
[0045]
Further, the polyamide fiber strands 40 absorb the impurities, such as moisture and chlorine due to the steam in the autoclave, remaining in the gap between the outer cover 39 and the braided pipe 38 and between the strands of the braided pipe 38. It is difficult to leave moisture and impurities on the surface. For this reason, the passivation film on the surface of the SUS wire 41 is hardly broken, and rust is hardly generated on the mesh tube .
[0046]
Even if the ratio of the SUS wire 41 of the mesh tube 38 is reduced by the above configuration, the flexibility and elasticity of the flexible tube portion 15 can be improved by overlapping the spiral tube 37 two or three times. And other mechanical properties.
[0047]
As described above, according to the mesh tube 38 of the present embodiment, since the strand bundle is formed by combining the conductive metal material and the electrically insulating material, electricity between the strands of the conductive metal material is reduced. It is difficult to flow, the anode / cathode reaction can be suppressed, and rust of the mesh tube caused by repeating autoclave sterilization (high-pressure high-temperature steam sterilization) can be prevented. Therefore, it is possible to solve the problem that rust is easily generated particularly when the endoscope is sterilized using autoclave sterilization (high-pressure high-temperature steam sterilization).
[0048]
In addition, water vapor impurities used for autoclave sterilization may stick to the surface of the outer skin 39 and cause yellowing. However, the outer skin 39 uses the yellow indicator 43 on the black resin, so that yellowing due to repeated autoclave sterilization is performed. Does not change the visibility.
[0049]
(2nd Embodiment)
A second embodiment of the present invention will be described with reference to FIG. In the present embodiment, the polyamide fiber strand 40 of the mesh tube 38 is replaced with an electrically insulating and water-repellent fluorine resin strand 44, for example, and the fluorine resin strand 44 and the SUS strand are used. The wire bundle 42 is configured by alternately and parallelly arranging 41, and the other configuration is the same as that of the first embodiment. Therefore, the fluorine resin wire 44 is thicker than the SUS wire 41. Note that the wire bundle 42 may have a configuration in which the ratio of the fluororesin wires 44 is larger than that in which both wires are alternately arranged.
[0050]
Also in the present embodiment, since the SUS strand 41 is thinner than the fluororesin strand 44, the gap between the SUS strands 41 is widened even in the portion where the strand bundles 42 overlap, and a difference in ion concentration inside and outside the gap is less likely to occur. Become. In addition, since the conductive SUS wires 41 are not adjacent to each other and are electrically insulated, the flow of electrons in the conductive material necessary for the rust anode / cathode reaction is suppressed. Furthermore, the fluorine-based resin wire 44 repels water due to steam in the autoclave, which remains in the gap between the outer cover 39 and the mesh tube 38 and between the wires of the mesh tube 38, and the water on the surface of the SUS wire 41 is easily evaporated. Become. Therefore, the mesh tube 38 is less likely to rust as in the case of the mesh tube 38 of the first embodiment.
[0051]
The present invention is not limited to the embodiments described above, but can be applied to other embodiments. According to the above description, the following items and items obtained by arbitrarily combining the items listed below can be obtained.
[0052]
<Appendix>
1) A flexible tube for an endoscope, comprising: a reticulated tube formed by using a wire bundle formed by arranging at least two or more wires, and a sheath covered with the reticulated tube and made of a polymer material; A flexible tube for an endoscope, wherein a wire bundle is formed by combining a wire made of one or more electrically insulating materials and a wire made of a conductive metal material.
2) The flexible tube for an endoscope according to 1), wherein a wire made of an electrically insulating material is thicker than a wire made of a conductive metal material.
3) The flexible tube for an endoscope according to 1), wherein wires made of a conductive metal material are arranged so as not to be adjacent to each other.
4) The flexible tube for an endoscope according to 1), wherein the wire made of an electrically insulating material is a water-absorbing wire.
5) The flexible tube for an endoscope according to 1), wherein the wire made of an electrically insulating material is a water-repellent wire.
[0053]
The function of the additional item 1 is to suppress the anode / cathode reaction by reducing the flow of electricity between the conductive metal material strands.
The effect of the additional item 2 is that the gap formed in the overlapping portion of the conductive metal material wires becomes large, and the distance between the conductive metal material wires arranged across the insulating material wire also becomes large, The local ion concentration difference is less likely to occur in the atmosphere around the conductive metal material, and crevice corrosion is less likely to occur.
The effect of the additional item 3 is that, since the conductive metal material strands are not adjacent to each other, there is no flow of electricity between the adjacent strands, and the anode / cathode reaction is further suppressed.
Supplementary note 4 describes that the insulating material wires absorb moisture and impurities remaining in the gap between the outer cover and the mesh tube and between the wires of the mesh tube due to the steam of the autoclave, and the surface of the conductive metal material wires absorbs moisture and impurities. Is difficult to leave.
The function of the additional item 5 is that the water remaining in the gap between the outer cover and the mesh tube or between the wires of the mesh tube due to the steam of the autoclave is repelled by the insulating material wires, so that the water is easily evaporated. .
[0054]
【The invention's effect】
As described above, according to the present invention, it is possible to prevent rust of a mesh tube caused by repeating autoclave sterilization, which is provided in the prior art.
[Brief description of the drawings]
FIG. 1 is a perspective view schematically showing an entire configuration including an endoscope apparatus and peripheral devices according to a first embodiment of the present invention.
FIG. 2 is an explanatory diagram of a flexible tube of the endoscope insertion section according to the first embodiment of the present invention.
FIG. 3 is an enlarged perspective view showing a mesh tube of a flexible tube of the endoscope insertion section according to the first embodiment of the present invention.
[Explanation of symbols]
2 Endoscope 7 Insertion part 8 Operation part 9 Universal cord 15 Flexible tube 16 Curved part 37 Spiral tube 38 Reticulated tube 39 Outer skin 40 Polyamide fiber 41 41 SUS wire 42 … Wire bundle 44… fluorine resin wire

Claims (1)

In a flexible tube for an endoscope having a reticulated tube configured by using a wire bundle formed by bundling at least two or more wires, and an outer sheath made of a polymer material covered with the reticulated tube,
The flexible tube for an endoscope, wherein the wire bundle is formed by combining a wire made of one or more electrically insulating materials and a wire made of a conductive metal material.

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