JP2003210556A - Pipe sterilizer with plasma - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pipe sterilizer with plasma which is usable for sterilizing the inner surface of a fine pipe. <P>SOLUTION: The pipe sterilizer with plasma 10 is constituted of a discharge part 3 for generating discharge plasma, a power supply cable 4, a discharge power source 5, and a transfer mechanism 6 for transferring the discharge part 3 within a fine pipe 2. A discharge electrode comprising an external electrode and a central electrode is arranged coaxially with the supply cable 4 at the end of the supply cable 4, and the external electrode is grounded. This pipe sterilizer 10 is constituted so as to generate a discharge plasma when a high voltage is applied to the central electrode. The discharge part 3 is transferred to a desired position within the fine pipe 2 by the transfer mechanism 6, and then a discharge plasma is generated at that position. By repeating the same operations, the whole inner surface of the fine pipe 2 is uniformly sterilized. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma sterilizer for pipes which uses discharge plasma to sterilize the inner surface of a fine pipe such as an endoscope.

[0002]

2. Description of the Related Art In recent years, the decomposition of NOx and SOx,
Plasma is becoming indispensable for the technology of removing harmful substances. The reason is that inelastic collisions of electrons in the plasma cause reactions such as excitation, dissociation, and ionization in the gas, resulting in the abundance of chemically active particles. This is because the harmful components can be decomposed by introducing them into the air containing the components and performing various chemical reactions there. In particular, the plasma sterilization technique has the advantages that the equipment is simpler and the handling is easier than the conventional heating method or chemical treatment method.

Hereinafter, a plasma sterilizer having such excellent characteristics will be described with reference to the drawings. Figure 7
FIG. 1 is a schematic cross-sectional view of a plasma sterilizer that has been conventionally used. In the figure, 11 is a container of the sterilizer, in which a plasma generator 13 is provided. Further, the inside of the container 11 is a pressure control device 1 provided outside.
By 2, the pressure is reduced to the optimum pressure for plasma generation. Further, a substance (gas or liquid) that has a sterilizing effect and is a source of the radical or radical species is also configured to be supplied from the pressure control device 12 into the container 11. The plasma generator 13 is, for example, a capacitively coupled or inductively coupled high frequency drive plasma source. The plasma generated by this plasma generator 13 is
The flow is as shown by the arrow in the figure, and is configured to be supplied to the instrument to be sterilized (hereinafter referred to as the instrument to be sterilized) 14 housed in the container 11.

Further, as a method for sterilizing the inner surface of a deep container such as a bottle or a plastic bottle into which foods, medicines, etc. are put, there is one described in the "sterilizer inside container" of Japanese Patent No. 2540276. That is, as shown in FIG. 8, the electrode rod 17 and the gas nozzle 18 are inserted into each container 16 which is an instrument to be sterilized and positioned on the metal pallet 15, and the gas nozzle 18 is used to generate a gas for plasma generation. When the electrode rod 17 emits a high frequency, a low-temperature plasma is generated between each electrode 17 and the metal pallet 15 connected to the ground. It is a sterilizer.

[0005]

By the way, the conventional plasma sterilizer as described above is not necessarily suitable for sterilization of fine tubes. For example, the plasma sterilizer as shown in FIG. 8 is used when the plasma floating in the sterilizer does not easily flow into the sterilization instrument, but the thin tube as thin as the electrode diameter and the contents of the sterilizer are used. It was not suitable for sterilization of long and slender tubes, etc.

That is, when the outer diameter of the electrode is close to the inner diameter of the thin tube to be sterilized, the discharge plasma generated around the electrode may directly act on the inner wall of the thin tube to cause damage. Further, if the thin tube is too long, there is a problem that the plasma is biased to a portion near the container wall of the sterilizer. This is because if the distance between the electrode and the inner surface of the container that is grounded is partially large, the electric field is discharged only in a region where the electric field is strong and the distance between them is short. As described above, the conventional plasma sterilizer has a problem that the inner surface of the microtube cannot be effectively sterilized.

The present invention has been proposed in order to solve the above-mentioned problems of the prior art, and an object thereof is to provide a plasma sterilizer for tubes which is effective for sterilizing the inner surface of a micro tube. It is in.

[0008]

In order to achieve the above-mentioned object, the invention according to claim 1 is a plasma sterilizer for tubes for sterilizing the inside of a thin tube by discharge plasma.
A discharge unit for generating the discharge plasma, a power supply for supplying power to the discharge unit via a power supply cable, and a moving mechanism for moving the discharge unit to a desired position inside the capillary. is there. According to the invention of claim 1, since the discharge part can be installed in the thin tube and the discharge part can be moved to a desired position inside the thin tube, the inner surface is effective for sterilization over the entire length of the thin tube. The inner surface of the capillary can be uniformly sterilized.

According to a second aspect of the present invention, in the plasma sterilization apparatus for pipes according to the first aspect, the moving mechanism is configured to operate in accordance with a program instructing a moving state input in advance. It is what According to the invention of claim 2, since the moving mechanism of the discharging unit is controlled by the preset program, the operability is further improved.

According to a third aspect of the present invention, in the plasma sterilizer for pipes according to the first or second aspect, the discharge part is composed of a surface electrode and one or more needle electrodes facing the surface electrode. A voltage is applied between these electrodes to generate discharge plasma. Claim 4
The invention according to claim 1 is the plasma sterilizer for pipes according to claim 1 or 2, wherein the discharge part is composed of a base made of an insulator and two or more electrodes juxtaposed on the surface thereof. A voltage is applied between the electrodes to generate discharge plasma.

According to a fifth aspect of the present invention, in the plasma sterilizer for pipes according to the third or fourth aspect, a part or all of the electrodes constituting the discharge part have their surfaces covered with an insulator. It is characterized in that it is composed of a conductor. The invention described in claim 6 is claim 1
The plasma sterilizer for pipes according to any one of claims 5 to 6, wherein the power supply cable is composed of a coaxial electric wire, parallel two-wire electric wire, or two or more stranded wires. It is what According to the inventions of claims 3 to 6, more stable sterilization can be realized.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a plasma sterilizer for pipes according to the present invention will be described below with reference to the drawings. (1) First Embodiment (Structure) FIG. 1 is a schematic diagram showing an endoscope which is an instrument to be sterilized and a plasma sterilizer for pipes of the present embodiment which is inserted into the endoscope to sterilize it. Is. In FIG. 1, 1
Represents an endoscope, and a micro tube 2 having a diameter of about several mm passes through the inside thereof, and in order to sterilize the inside of the micro tube 2, the plasma sterilizing apparatus 10 for a tube of the present embodiment is inserted into the micro tube 2. Has been done. The plasma sterilizer 10 for tubes includes a discharge section 3 for generating discharge plasma, a power supply cable 4, a discharge power supply 5, and a discharge section moving mechanism 6 for moving the discharge section 3 in the fine tube 2. The power supply cable 4 is
It also has a role of holding the discharge unit 3.

Further, FIG. 2 and FIG. 3 show one of the discharge parts 3.
FIG. 2 is a longitudinal sectional view and FIG. 3 is a plan view showing an example. That is, at the tip of the power supply cable 4, a discharge electrode composed of the external electrode 31 and the center electrode 32 is arranged coaxially with the power supply cable 4, and the external electrode 31 is grounded. Then, when a high voltage is applied to the center electrode 32, discharge plasma 33 is generated. The radical species generated therein diffuse in the direction of the arrow in the figure and sterilize on the wall surface of the fine tube (not shown). In the figure,
The external electrode 31 has a cylindrical shape, but may be made of mesh, punch metal, or a perforated cylinder.

As the moving mechanism 6 of the discharging section 3, for example, a mechanism in which the power feeding cable 4 is wound around a drum and the power feeding cable 4 is rolled up or extended by the rotation of the drum is used. In addition, if the moving mechanism 6 is provided with a function capable of automatically moving the discharge unit 3 in accordance with a moving program input in advance, the operability of the apparatus is further improved.

The arrangement of the power supply lines in the power supply cable 4 includes a coaxial system, a parallel two-wire system, a system in which two wires are twisted, and the like. Also, the discharge power source 5
Is a direct current, if it is possible to apply a voltage enough to start the discharge between the discharge electrodes and maintain the discharge.
Either exchange is acceptable. Further, although FIG. 1 illustrates the treatment in the atmosphere in mind, the entire apparatus to be sterilized and the plasma sterilizer for pipes are enclosed in a closed container, and a substance effective for sterilization such as hydrogen peroxide is included. It may be possible to process in gas.

(Operation / Effect) The tube plasma sterilization apparatus of the present embodiment having such a configuration performs the sterilization process of the microtube 2 provided in the endoscope 1 as follows. That is, the discharge part 3 of the plasma sterilizer 10 for tubes is inserted from one opening 2a of the microtube 2 provided in the endoscope 1 to the other end, and the discharge is ignited here. In the plasma generated by the discharge, for example, ozone or other radical species is generated in the air atmosphere, and the inner wall of the fine tube 2 around the discharge part 3 is sterilized by this. Then, the moving mechanism 6 moves the discharge part 3 to a desired position in the micro tube 2, and discharge plasma is generated at that position. By repeating this operation, the entire inner wall surface of the fine tube 2 can be uniformly sterilized.

As described above, in the present embodiment, the inner surface of the fine tube is constructed by disposing the discharge portion for generating the discharge plasma in the fine tube and allowing the discharge portion to move in the tube. Is uniformly exposed to the discharge plasma,
As a result, the inner wall surface of the microtube can be exposed to a component effective for sterilization over the entire length thereof, so that the inner surface of the microtube can be effectively sterilized.

(2) Second Embodiment This embodiment is a modification of the first embodiment and is shown in FIG.
As shown in FIG. 3, the external electrode 41 provided in the discharge part 3 is formed into a flat plate, and is broken down by the high voltage applied to the needle electrode 32 that is the center electrode, and the discharge plasma 33 is generated. There is. In addition, also in this embodiment, the same operation and effect as those of the first embodiment can be obtained.

(3) Third Embodiment This embodiment is a modification of the first embodiment described above and is shown in FIG.
, One of the discharge electrodes (in the figure, the external electrode 3
The surface facing the counter electrode of 1) (the central electrode 32 in the figure) is covered with an insulator 34. With such a configuration, the discharge becomes a dielectric barrier discharge, and the controllability becomes more excellent. Of course, both electrodes may be covered with an insulator. In addition, also in this embodiment, the same operation and effect as those of the first embodiment can be obtained.

(4) Fourth Embodiment This embodiment is a modification of the first embodiment and is shown in FIG.
As shown in FIG. 3, a pair of electrodes 51 and 52 for generating discharge plasma are arranged side by side on the insulator 35.
In this case, the discharge plasma 33 is generated near the surface of the insulator 35 and breaks down along the surface of the insulator 35, so that a more stable discharge than the discharge in the air can be obtained. Note that part or all of the electrodes may be covered with an insulator. In addition, also in this embodiment, the same operation and effect as those of the first embodiment can be obtained.

(5) Other Embodiments The present invention is not limited to the above-described embodiments, and the shape, size, thickness, etc. of the discharge part are appropriately changed in accordance with the instrument to be sterilized. be able to.

[0022]

As described above, according to the present invention, the discharge part is installed in the fine tube which is the instrument to be sterilized, and the inside of the fine tube is moved so that the inner surface of the fine tube is uniformly exposed to the discharge plasma. By doing so, it is possible to provide a plasma sterilizer for tubes that is effective for sterilizing the inner surface of the microtube.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the configuration of a first embodiment of a plasma sterilization apparatus for tubes according to the present invention.

FIG. 2 is a vertical cross-sectional view showing the configuration of the discharge part of the first embodiment.

FIG. 3 is a plan view showing a configuration of a discharge unit of the first embodiment.

FIG. 4 is a schematic diagram showing the configuration of a second embodiment of the plasma sterilization apparatus for tubes according to the present invention.

FIG. 5 is a schematic diagram showing the configuration of a third embodiment of the plasma sterilization apparatus for tubes according to the present invention.

FIG. 6 is a schematic view showing the configuration of a fourth embodiment of the plasma sterilization apparatus for tubes according to the present invention.

FIG. 7 is a schematic diagram showing the configuration of a conventional plasma sterilization apparatus.

FIG. 8 is a schematic diagram showing a configuration of a conventional plasma sterilization apparatus.

[Explanation of symbols]

1 ... Endoscope 2 ... fine tube 3 ... Discharge part 4 ... Power supply cable 5 ... Discharge power supply 6 ... Discharge unit moving mechanism 10 ... Plasma sterilizer for tubes 11 ... Container 12 ... Pressure control device 13 ... Plasma generator 14 ... Instrument to be sterilized 15 ... Metal pallet 16 ... Container 17 ... Electrode rod 18 ... Gas nozzle 31, 41, 51 ... External electrodes 32, 52 ... Center electrode 33 ... Discharge plasma 34, 35 ... Insulator

Claims (6)

[Claims] 1. A plasma sterilizer for pipes, which sterilizes the inside of a thin tube with discharge plasma, comprising: a discharge unit for generating the discharge plasma; a power supply for supplying power to the discharge unit via a power supply cable; A plasma sterilizer for tubes, comprising a moving mechanism for moving the tube to a desired position inside the tube. 2. The plasma sterilizer for tubes according to claim 1, wherein the moving mechanism is configured to operate in accordance with a program that is input in advance to instruct a moving state. 3. The discharge part is composed of a surface electrode and one or more needle electrodes facing the surface electrode, and a voltage is applied between these electrodes to generate discharge plasma. The plasma sterilizer for pipes according to claim 1 or 2. 4. The discharge part is composed of a base made of an insulator and two or more electrodes arranged in parallel on the surface of the base, and a voltage is applied between these electrodes to generate discharge plasma. The plasma sterilizer for pipes according to claim 1 or 2. 5. The pipe according to claim 3 or 4, wherein a part or all of the electrodes forming the discharge part are made of a conductor whose surface is covered with an insulator. Plasma sterilizer. 6. The power supply cable is an electric wire in a coaxial state,
The pipe plasma sterilizer according to any one of claims 1 to 5, wherein the plasma sterilizer for a pipe according to any one of claims 1 to 5, wherein the plasma sterilizer is composed of either two parallel wires or two or more twisted wires.