Coating processes – Electrical product produced – Wire conductor
Patent
1991-08-22
1994-03-22
Beck, Shrive
Coating processes
Electrical product produced
Wire conductor
427120, 4271263, 4273764, 427387, 4274193, 427427, 427435, 205188, 205209, B05N 512
Patent
active
052962601
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a method of manufacturing an inorganic insulation such as a heat resistant wire/coil etc., a radiation resistant wire or coil which is related to nuclear power, or a wire or coil for a vacuum apparatus, or the like.
BACKGROUND ART
As a conventional heat resistant wire etc., there is an MI cable, a fiber-glass braided wire, or a wire passing a ceramics tube. However, such a wire is bulky and disadvantageous in view of space. Further, the wire has such a disadvantage that its configuration is apt to be restricted to a round wire.
While a heat resistant organic wire whose surface is coated with an organic material is also known, such a wire cannot withstand a temperature exceeding 300.degree. C., and has a problem in heat resistance. Further, discharge of cracked gas, as well as discharge of adsorbed gas come into question.
As to a heat resistant wire, known are a method of applying a ceramics precursor which is prepared by a sol-gel method to a surface, and a Nippon Sheet Glass method [Liquid Phase Deposition (LPD) method]. However, these methods have such problems that it takes time for increasing film thicknesses.
Known is a method of applying a material which is obtained by mixing ceramics particles into silicone resin onto the surface of a wire or the like and thereafter heating/firing the same. According to this method, however, there is such a problem that the surface of the wire or the like is irregularized and roughened, and weakened against rubbing. It also has a problem in view of flexibility.
Also when films are formed by a spraying method and a sintering method, surfaces are irregularized or made porous. Thus, similar problems are caused.
DISCLOSURE OF THE INVENTION
An object of the present invention is to provide a method of manufacturing an inorganic insulation which is easy to industrialize, improved in workability, as well as improved in insulability and reliability of non-outgassing property.
The manufacturing method according to the present invention comprises a step of forming a ceramics film having irregularity on its surface on a conductor surface, a step of applying a solution of a ceramics precursor prepared from at least one or two types of metal alkoxides or metal acylates onto the ceramics film for filling up irregular portions on the surface of the ceramics film, and a step of at least partially changing the solution of the ceramics precursor to a ceramics state by heating.
In the present invention, the ceramics film having irregularity on its surface indicates such a state that Ra of the surface of the ceramics film is at least 1 .mu.m.
In the present invention, further, a porous ceramics film is included in the ceramics film having irregularity on its surface.
In a first embodiment according to the present invention, it is possible to form a ceramics film by a spraying method, a particle sintering method or an electric deposition method.
In the present invention, the conductor in a state after formation of ceramics may be worked into a desired configuration before application of the ceramics precursor solution.
In a second embodiment according to the present invention, the ceramics film is formed by applying a mixture of silicone resin and ceramics particles and/or ceramics fiber onto the surface of the conductor, performing first heat treatment within such a temperature range that the silicone resin is not changed to a ceramics state for forming a film, and further performing second heat treatment for changing the same to a ceramics state.
When it is desirable to work the conductor into a desired configuration in this embodiment, the conductor is preferably worked into a desired configuration after the first heat treatment and before the second heat treatment.
In this embodiment, a condition for the second heat treatment is preferably a condition of changing at least 90% to a ceramics state.
As to the ceramics precursor, there is a precursor which is prepared from an alkoxide or an acylate of Si, Al, Zr, Ti, or Mg, for exam
REFERENCES:
patent: 4269894 (1981-05-01), Sakai et al.
patent: 4468420 (1984-08-01), Kawahara et al.
patent: 4476192 (1984-10-01), Imai et al.
patent: 4983423 (1991-01-01), Goldsmith
patent: 5105531 (1992-04-01), Sawada et al.
patent: 5112676 (1992-05-01), Cot et al.
patent: 5139820 (1992-08-01), Sawada et al.
Inazawa Shinji
Sawada Kazuo
Yamada Kouichi
Beck Shrive
Fasse W. G.
Sumitomo Electric Industries Ltd.
Utech Benjamin L.
LandOfFree
Method of manufacturing inorganic insulation does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of manufacturing inorganic insulation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of manufacturing inorganic insulation will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-435325