JPS5843474B2 - Method and device for forming a film on the inner wall of a tubule - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for forming a film on the inner wall of a capillary, and more particularly to a method and apparatus for forming a film on the inner wall of a capillary, which are suitable for electrolytic treatment of the inner wall of a bent capillary or the like.

Generally, the surface of metal members used as building materials and the like is treated with an oxide film in order to increase their corrosion resistance and surface hardness.

In addition to the above-mentioned properties such as increased corrosion resistance, this oxide film has various properties such as dyeability, insulation properties, and improved light reflectance, so it can be formed and used on various metal members as needed. has been done.

This type of oxide film, such as an anode film, is generally
It is formed by immersing a metal, connected to the anode side, as a film-forming member into an electrolytic solution such as dilute sulfuric acid filled in a reaction vessel, and then electrolyzing it.

However, in such conventional technology, when the film-forming member is a bent thin tube used in a refrigerator condenser, for example, even if a constant potential for an anode is applied to the bent thin tube, the electrolyte inside the tube is , since the surroundings are at equal potential, the whole is at equal potential, and no potential gradient occurs.

For this reason, there was a problem in that no oxide film was formed on the inner wall of the bent tube.

Such inconveniences occur not only particularly in the case of bent tubules, but also in ordinary tubules, and also in cases such as inside members where the inner wall portion is constricted and it is difficult to generate a potential gradient.

For this reason, in recent years, electrode wires have been inserted and laid inside thin tubes, spacers have been installed at multiple locations to prevent the electrode wires from coming into contact with the inner wall, and then the electrolyte is allowed to flow inside. A method has been published in which a potential gradient is formed between the electrode wire and the inner wall of the capillary through the electrode wire, thereby forming an oxide film directly on the inner wall of the capillary 9.

However, in such conventional examples, a large number of spacers are required to support the electrode wires, and countless dot-like or thin-line film irregularities occur on the inner wall of the thin tube in which the spacers are inscribed. There is a problem in that the film on the inner wall of the spacer portion is not uniformly formed.

An object of the present invention is to improve the above-mentioned disadvantages of the prior art, and to be able to reliably form an electrolytic film in places where it is difficult to form an electrolytic film under normal electrolytic conditions, such as the inner wall of a metal tube. An object of the present invention is to provide a method and apparatus for forming a film on the inner wall of a bent tubule, which is suitable for forming a film on the inner wall of a bent tubule.

Therefore, the present invention provides an electrode wire mechanism that is inserted into a thin tube and has a partially exposed portion and is formed so that the exposed portion does not come into contact with the inner wall of the thin tube, and that the electrode wire mechanism is exposed. The above object is achieved by adopting a configuration in which the electrode wire mechanism is gradually moved while creating a potential gradient between the electrode wire mechanism and the inner wall of the thin tube through an electrolytic solution. be.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially omitted sectional view showing the basic structure of the present invention, in which 1 shows the end of a relatively long thin tube 1, and 2 shows an electrode wire loosely inserted into the thin tube. The mechanism is shown.

This electrode wire mechanism 2 is composed of an electrode wire 2A covered with a soft insulator such as vinyl, and an electrode part 3 fixed to the terminal ends of the two electrode wires.

Among these, the electrode part 3 & also includes a substantially spherical electrode body 3A directly fixed to the two electrode wires, and a center part of the right end surface of this electrode body 3A in FIG. The insulation film 3B has high abrasion resistance and covers the entire outer surface of the insulating film 3B.

Then, an external DC power source 4 applies a negative potential to the two electrode wires, and a positive potential to the bent tubule 1.
They are applied respectively.

Now, when an electrolytic solution, for example, dilute sulfuric acid with a concentration of 15% is passed through the bent tube 1 at 20° C., and then a negative potential is applied to the electrode wire 2A and a positive potential is simultaneously applied to the bent tube 1, the electrode body A potential gradient is generated between the right end surface of 3A in FIG. 1 and the surrounding inner wall of the bent tubule 1A, and as a result, an oxide film is formed on the inner wall portion of the bent tubule 1 where the electrode body 3A is located.

Next, by moving the entire electrode wire mechanism 2 in the direction of arrow A in FIG. 1 while maintaining this state, an oxide film is successively and reliably and smoothly formed on the inner wall of the bent thin tube 1.

In this case, the two electrode wires may be made of a soft material such as copper or aluminum, or may be formed by twisting these metal wires together into a fine wire.

Furthermore, when a plurality of the electrode portions 3 are provided at predetermined intervals as shown in FIG. 2 and FIG. 3, the efficiency of film formation can be significantly improved.

FIG. 3 is an explanatory view of the case where the electrode wire mechanism 2 described above is inserted and arranged in the bent thin tube 1.

In this case, a relatively light spherical block 11 made of synthetic resin or the like is fixed to the tip of the electrode wire mechanism 2, and the tip is fitted into a skirt-shaped guide member 11 as shown in the figure.
is installed and L・ru.

This skirt-shaped guide member 12 is made of a flexible face piece, and a plurality of small holes 12A for fluid passage are provided in positions close to the spherical block 11.

The guide portion 13 formed in this manner is placed at one end 1A of the bent thin tube 1 as shown in FIG. 2, and then gas or liquid is forced to circulate from the outside of the bent thin tube 1. Guided by the skirt-like guide member 12, the electrode wire mechanism 2 is inserted into the bent thin tube 1 as shown in FIG.

In this case, the skirt-shaped guide member 12 of the guide portion 13
The guide portion 13 can always maintain the state shown in FIG. The electrode wire mechanism 2 is smoothly inserted into the bent thin tube 1 as a whole.

In addition, if the length of the widening part of the skirt-shaped guide member 12 (the length in the left-right direction in FIG. Since the light portion of the portion 13 is always located at the tip in the moving direction, the guide portion 13 can perform its function in a more stable state.

FIG. 4 shows a schematic front view of the bent thin tube 1 into which the electrode wire mechanism 2 is inserted, as shown in FIG.

In this figure, ends 'iA and 1B of the bent thin tube 1 are connected to a liquid supply system 21 and a liquid return system 22, respectively.

Among these, the liquid supply system 21 includes an electrolyte storage tank 23 for temporarily storing an electrolyte, and a temperature adjustment mechanism 24 for maintaining the temperature of the electrolyte sent out from the electrolyte storage tank 23 at a substantially constant level. and a liquid circulation pump 2 for circulating the electrolyte.
5 and a pipe 26 connecting these parts, one end 1A of the bent thin tube 1 connects to a first connecting mechanism 27 mainly consisting of a cylindrical hollow connecting member 27A made of an insulating material.
It is connected to the liquid supply system 21 via.

Further, the liquid return system 22 includes the other end 1 of the bent thin tube 1.
The pipe 28 connected from B to the electrolyte storage tank 23 described above is provided as its main part, and the other end 1 of the bent thin tube 1
B connects the piping 2 of the liquid return system 22 via a second connection mechanism 29 mainly consisting of a three-way connection member 29A made of an insulating material.
8 is connected.

As shown in FIG. 4, the bent thin tube 1 is installed such that one end 1A thereof is located below and the other end 1B is located above.

As shown in FIG. 7, the first connection mechanism 27 on the side of the liquid supply system 21 is composed of the aforementioned cylindrical hollow connection member 27A and fastening members 27B, 27B provided on the outer periphery of both ends thereof. As a result, one end 1A of the bent thin tube 1
and the pipe 26 of the liquid supply system 21 are removably connected, and electrically insulated between them.

The second connection mechanism 29 on the side of the liquid return system 22 includes the aforementioned three-way connection member 29A, and fastening members 29B, 29B, and 29B provided on the outer periphery of each end of the three-way connection member 29A.
It is composed of.

As shown in FIG. 4 or 6, the other end 1B of the bent thin tube 1 described above is attached to the leftward protruding end of this three-way connecting member 29A, and the downwardly protruding end The upper end of the piping 28 of the liquid return system 22 described above is connected to the liquid return system 22 at a temperature of .degree.

The upwardly protruding end of the three-way connecting member 29A extends upward for a relatively long time, and above the end is a winding mechanism 30 for slowly winding up the electrode wire mechanism 2 described above. It is attached.

This winding mechanism 30 includes a pulley 31 that is rotated by a motor and a speed reducer (not shown), and an electric system 31A that applies a negative potential from a power source 32 to the electrode wire 2A of the electrode wire mechanism 2 via the pulley 31. (see FIG. 4), and a control unit (not shown) for controlling the rotational speed of the pulley 31 in order to keep the winding speed of the electrode wire mechanism 20 substantially constant.
It is composed of.

Further, a positive potential is applied from the power source 32 to the bent thin tube 1 arranged and equipped as shown in FIG.

Further, the above-described oxide film forming device 90 further includes a traveling biasing mechanism 40 for helping the electrode wire mechanism 2 to move gently while the electrode wire mechanism 2 is installed inside the bent thin tube 1. is installed parallel to and close to the curved surface of the

In this embodiment, the traveling biasing mechanism 40 is composed of a plurality of rotating magnet disks 41, 41, .・Ru.

In this embodiment, each rotating magnet disk 41 is made of a rubber magnet mounted on a rotating disk (not shown) made of synthetic resin so as to face the bent portion of the bent thin tube 10, and its magnetic poles N, S As shown in FIG. 5, N and S poles are formed radially at a predetermined interval.

Next, the operation and function of the oxide film forming apparatus 90 shown in FIG. 4 will be explained.

First, when the liquid circulation pump 25 of the liquid supply system 21 is operated,
The electrolyte is supplied from the electrolyte storage tank 23 to the one end 1A of the bent tube 1 via the liquid supply system 21, and then flows through the bent tube 1 at L.sub. It is fed into the storage tank 23, and this state is continued continuously thereafter.

During this time, by operating the temperature adjustment mechanism 24 of the liquid supply system 21, the electrolytic solution is operated so as to be able to maintain a predetermined temperature at all times.

Next, the power supply 32 is switched on, and a positive potential is applied to the bent thin tube 1 and a negative potential is applied to the two electrode wires of the electrode wire mechanism 2.
When activated, the electrode wire mechanism 2 slowly travels inside the bent tube 1.

On the other hand, since a potential gradient is forcibly formed between the plurality of electrode bodies 3A of the electrode wire mechanism 2 and the inner wall of the bent thin tube 1 in the vicinity thereof, the inner wall of the bent thin tube 1 is Formation of the anode film starts at the same time as L, and its range gradually expands over the entire area as the electrode wire mechanism 20 travels.

Therefore, when there are a plurality of electrode parts 3, a predetermined electrolytic film can be formed more quickly and accurately within the bent thin tube 1.

As described above, according to the present invention, it is possible to form an electrolytic film on the inner wall of a thin tube, etc., which has been considered difficult in the past.
This can be done very easily and smoothly, and since the electrolytic film is formed sequentially and continuously on the inner wall of the thin tube etc. as described above while the electrode wire mechanism is traveling, the ratio of the amount of traveling movement of the electrode wire mechanism can be reduced. This allows the range of film formation on the inner wall of a capillary to be recognized from the outside, and since there is no member that comes into contact with the inner wall of the capillary and stops at that position, the film is formed uniformly over the entire inner wall of the capillary, etc. It is possible to provide an unprecedented and excellent method for forming an oxide film and an apparatus therefor, which can form an electrolytic film of

In addition, although the above-mentioned embodiment illustrated the formation of an electrolytic film on the inner wall of a bent thin tube or the like, the present invention is not necessarily limited thereto.

Further, in the above-mentioned embodiment, a case has been described in which a sulfuric acid solution having a concentration of 15 parts is used as the electrolytic solution, and the bent tube 1 is set to a positive potential, and the electrode wire 2A is set to a negative potential. However, the present invention does not necessarily apply to this. There is no limitation, and the applied potential may be switched between positive and negative depending on the properties of the electrolytic solution.

Furthermore, although the case of one bent tube 1 &L was illustrated, under the same conditions, a plurality of bent tubes are installed between the liquid supply system 21 and the liquid return system 22, and the inner wall of these tubes is An electrolytic film may be formed at the same time.

[Brief Description of the Drawings] Fig. 1 is a partially omitted sectional view showing one embodiment of the present invention;
2 and 3 are explanatory diagrams showing a method of inserting an electrode wire mechanism into a bent capillary tube, FIG. 4 is a schematic front view showing an example of the device according to the present invention, and FIG. 5 is a diagram similar to that shown in FIG. 4. FIG. 6 is a front view showing the rotating magnet disk which is the main part of the travel biasing mechanism, FIG.
The figure is an enlarged sectional view showing the first coupling mechanism, and FIG. 8 is an enlarged partial sectional view showing the section ■ in FIG. 4. DESCRIPTION OF SYMBOLS 1... Bent tube as an example of a thin tube, 2... Electrode wire mechanism, 2A... Electrode wire coated with an insulator, 3A.
... Electrode body, 3B... Insulating film, 30... Winding mechanism.

Claims (1)

[Scope of Claims] 1. An electrode wire mechanism having an exposed portion of the electrode wire in a part thereof and formed so that the exposed portion does not come into contact with the inner wall of the thin tube is inserted and arranged in the thin tube, A method for forming a film on the inner wall of a capillary, the method comprising: gradually moving the electrode wire mechanism while creating a potential gradient between the exposed portion of the electrode wire mechanism and the inner wall of the capillary via an electrolyte. 2 Formation of a film on the inner wall of a capillary that includes an electrode wire mechanism disposed within the capillary and an electrical system that generates a predetermined potential gradient between the electrode wire mechanism and the inner wall of the capillary via an electrolyte. In the apparatus, the electrode wire mechanism is connected to a winding mechanism for winding the electrode wire mechanism upward, and the electrode wire mechanism is connected to a bendable electrode wire and at least one location on the electrode wire. and an electrode body attached to the electrode body, and a part of the central part of the electrode body along the electrode wire is exposed, and the other part of the electrode body and the entire moving part of the electrode wire are bent by an insulating member. A device for forming a film on the inner wall of a thin tube, characterized in that it is coated freely.