Patents Assigned to NKK Corporation
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Patent number: 5123957Abstract: A method for manufacturing a low carbon ferrochrome with a high chromium content of at least 70 weight % Cr comprising the steps of at least once nitriding and crushing a low carbon ferrochrome to form a crushed ferrochrome nitride and subjecting the crushed ferrochrome nitride to an acid treatment comprising introducing the crushed ferrochrome nitride into an acid solution and stirring the resultant mixture of the ferrochrome nitride and the acid solution, to remove iron. The acid treated ferrochrome nitride is denitrided by heating in a vacuum.Type: GrantFiled: October 30, 1989Date of Patent: June 23, 1992Assignee: NKK CorporationInventors: Masanori Kato, Toshio Kamatani, Keiichi Nakagawa, Kiyoshi Kawasaki, Yutaka Yano
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Patent number: 5124121Abstract: A titanium base alloy with improved superplastic, hot workability, cold workability, and mechanical properties is provided. The alloy has about 4% Al and 2.5% V, with below 0.15% O, with 2% Fe and 2% Mo, 0.85.about.3.15 wt. % Mo, and at least one element from the group of Fe, Ni, Co, and Cr as beta stabilizing elements, and as contributing elements to the lowering of beta transus, finally to the improvement of the superplastic properties, and hot and cold workability, with the grain size of below 5 .mu.m. A method of making thereof is provided with the reheating temperature between beta transus minus 250.degree. C. and beta transus.A method of superplastic forming thereof is provided with the heat treating temperature between beta transus minus 250.degree. C. and beta transus.Type: GrantFiled: June 24, 1991Date of Patent: June 23, 1992Assignee: NKK CorporationInventors: Atsushi Ogawa, Kuninori Minakawa, Kazuhide Takahashi
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Patent number: 5122498Abstract: A dye solvent useful as a material for microcapsules necessary for the manufacture of pressure-sensitive manifold paper. This solvent essentially consists of a hydroaromatic compound for pressure-sensitive manifold paper. The compound is a polycyclic aromatic compound with three or more aromatic rings, some of which rings have been hydrogenated and exhibits solvency, particularly, for a black pigment and a blue pigment of leuco dye.Type: GrantFiled: August 8, 1990Date of Patent: June 16, 1992Assignee: NKK CorporationInventors: Taisuke Nishida, Jun Miki, Tadao Kimura, Hiroaki Taniguchi
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Patent number: 5120615Abstract: A magnetic disk substrate composition 0.5 wt % to 1.0 wt % of Mo, 0.03 wt % to 0.5 wt % of O+2N+0.75C, and a balance of Ti. The alloy sheet having a composition of above range is cold-rolled at a rolling ratio of 30% or more to form a magnetic disk substrate material, and the material is thermal-flattened under the following condition:500.ltoreq.T.ltoreq.-(150/11).multidot.t+7850/111.ltoreq.twhere T represents a thermal-flattening temperature (.degree.C.), and t represents a thermal-flattening time (houre), thereby obtaining a magnetic disk substrate having the average grain size of 30 .mu.m or less.Type: GrantFiled: June 12, 1990Date of Patent: June 9, 1992Assignee: NKK CorporationInventors: Hideaki Fukai, Hiroyoshi Suenaga, Kuninori Minakawa
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Patent number: 5116435Abstract: A method for producing a non-oriented electrical steel sheet with precise thickness and homogeneous magnetic property comprising the steps of: making a steel ingot which has: 0.01 wt. % or less C, 0.003 wt. % or less N, 0.01 to 1.0 wt. % Mn, Al and Si satisfying, in wt. %, the formulas of: ##EQU1## provided that (Si %) represents the Si (wt. %) and (Al %) represents Al content (wt. %), and the balance being Fe and inevitable impurities to produce a steel slab; hot-rolling the slab at a finishing temperature of 700.degree. to 900.degree. C. into a steel strip and coiling the hot rolled strip; and cold-rolling the hot-rolled strip into a cold-rolled strip, followed by annealing the cold-rolled strip.Type: GrantFiled: March 27, 1989Date of Patent: May 26, 1992Assignee: NKK CorporationInventors: Akihiko Nishimoto, Yoshihiro Hosoya, Toshiaki Urabe
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Patent number: 5116436Abstract: Non-oriented electrical steel sheets having excellent magnetic properties are produced by carrying out a coiling at a low temperature for monitoring the amount of scale generation; de-scaling after hot rolling; and annealing the de-scaled hot rolled sheet in a non-oxidizing atmosphere to thereby minimize the oxidation and nitriding during annealing the hot rolled sheet. By determining a higher heating temperature for hot rolling, a magnetic property (magnetic flux density) is improved, and the hot rolled sheet is subjected to an open coil-annealing and annealing conditions therefor are specified in order to perfectly precipitate re-solute AlN particles by this heating and fully coarsen AlN particles.Type: GrantFiled: June 13, 1990Date of Patent: May 26, 1992Assignee: NKK CorporationInventors: Akihiko Nishimoto, Yoshihiro Hosoya, Kunikazu Tomita, Toshiaki Urabe, Masaharu Jitsukawa
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Patent number: 5115242Abstract: Disclosed is an in-furnace slag level measuring apparatus having a microwave radar for measuring a slag level in a convertor or the like. The level of a transmission signal or a reception signal is adjusted in accordance with the level of a detection signal so that the signal level in the microwave radar is adjusted to be constant. Further, the level measurement value and the detection signal are inputted and the level measurement values obtained in a predetermined time are subjected to averaging operation. In the averaging operation, when the detection signal is smaller than a set point, the averaging operation is performed while disregarding the level measurement value at that time.Type: GrantFiled: March 27, 1991Date of Patent: May 19, 1992Assignee: NKK CorporationInventors: Akio Nagamune, Kouichi Tezuka, Isamu Komine
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Patent number: 5114749Abstract: A method for manufacturing carbon material having good resistance to oxidation, comprising coating carbon material, which is a sintered body or a porous body, with an inorganic polysilazane; heating the carbon material coated with the inorganic polysilazane in an inert atmosphere to form amorphous silicon nitride on the surface of the carbon material; and reheating the heated carbon material in a non-nitriding and non-oxidizing atmosphere, the amorphous silicon nitride being decomposed and silicon carbide being formed on the surface of the carbon material; the reheating being conducted at a temperature of 1300.degree. C. to 1900.degree. C. and the non-nitriding and non-oxidizing atmosphere having a partial pressure of nitrogen determined with reference to a graph wherein the abscissa is a temperature in .degree.C. and the ordinate is partial pressure of nitrogen in atmospheres, the partial pressure being defined within an area under a line connecting a first point corresponding to 1300.degree. C. and 0.Type: GrantFiled: July 18, 1990Date of Patent: May 19, 1992Assignee: NKK CorporationInventors: Hiroaki Nishio, Keiji Watanabe, Michitaka Sato
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Patent number: 5112577Abstract: An apparatus for removing the dispersion medium in a metal or ceramic molded body which comprises a dispersion medium-removing vessel includes a condensing zone located in a upper part and a boiling zone located in a lower part, a separator to separater a solvent in the dispersion medium solution discharged from the vessel by heating the solution at a temperature higher than the boiling point of the solvent to evaporate it, the boiling zone being connected with the separator through a pipe to transport the dispersion medium solution and a pipe to transport the vaporized solvent to form a circuit, and a pump provided in the circuit. In the apparatus since the dispersion medium is removed in the boiling solvent, keeping a constant temperature is easy. The dispersion medium is promptly removed by contacting it with a solution of which the concentration of the dispersion medium is always low due to continuous removal of the dispersion medium in the separator. Since the boiling point of the solvent is about 20.Type: GrantFiled: September 7, 1990Date of Patent: May 12, 1992Assignee: NKK CorporationInventor: Hiroaki Nishio
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Patent number: 5110689Abstract: A first characteristic of the invention is present in forming a chromate film on the surface of a zinc or a zinc alloy plated steel sheet, and a resin composition film at a coating amount of 0.3 to 5.0 g/m.sup.2 on said chromate fim, said resin composition film comprising an organic solvent soluble epoxy resin and hydrophobic silica in a ratio of 80:20 to 50:50 by weight of epoxy resin:hydrophobic resin, said epoxy resin having a glass transition temperature of 293.degree. to 342.degree. K.A second characteristic of the invention is present in forming a chromate film on the surface of a zinc or zinc alloy plated steel sheet, and a resin composition film at a coating amount of 0.3 to 5.0 g/m.sup.2 on said chromate film, and resin composition film comprising an organic solvent soluble epoxy resin having glass transition temperature of 293.degree. to 342.degree. K.Type: GrantFiled: February 19, 1991Date of Patent: May 5, 1992Assignees: NKK Corporation, Kansai Paint Co., Ltd.Inventors: Tsutomu Watanabe, Masaaki Yamashita, Takahiro Kubota, Yoshiaki Miyosawa, Tadashi Nishimoto
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Patent number: 5108522Abstract: The present invention is to produce non-oriented electrical steel sheets having excellent magnetic property under low magnetic field by effectively checking thermal stress from introducing during cooling in a final annealing without decreasing productivity, for which when a silicon steel sheet having passed a cold rolling is cooled after a final continuous annealing, especial cooling conditions are specified only to a temperature range giving bad influences to the magnetic properties under the low magnetic field so as to prevent the introduction of the thermal strain.Type: GrantFiled: October 12, 1989Date of Patent: April 28, 1992Assignee: NKK CorporationInventors: Akihiko Nishimoto, Yoshihara Hosoya, Kunikazu Tomita, Toshiaki Urabe, Masaharu Jitsukawa
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Patent number: 5108521Abstract: For enabling the manufacture of non-oriented steel strips by HDR, the amounts of AlN and MnS which precipitate on the way of HDR are decreased to such a level that they do not affect the magnetic properties by regulating the Al and S contents, and further unavoidable precipitating nitrides are precipitated as coarse BN. With regard to the steel composition, the amounts of C, Si and P are not only regulated, but also the amounts of Mn, Al, S and N are regulated from the above standpoint, and a proper amount of B is added if required. In addition, in regard to treatment conditions, in order to secure necessary finishing and coiling temperatures, the lower limit of the slab temperature at the starting time of HDR is specified. Moreover, to secure precipitation of BN and recrystallization of a ferrite structure, the lower limits of the finishing and coiling temperatures are specified.Type: GrantFiled: August 20, 1991Date of Patent: April 28, 1992Assignee: NKK CorporationInventors: Yoshihiro Hosoya, Akihiko Nishimoto, Toshiaki Urabe
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Patent number: 5108678Abstract: This invention relates to a fiber reinforced plastic sheet having a gradient layer structure wherein the number of reinforcing fibers continuously varies and a process for producing the same by spreading a mixture of the fibers different in the number of filaments over the traveling zone of a conveyor and then pressing it while it contains a resin. The fiber reinforced plastic sheet of the invention is excellent in smooth appearance, fluidity during molding to an article, fiber filling ability into a complex form portion of an article and mechanical strength and can be produced inexpensively.Type: GrantFiled: April 27, 1990Date of Patent: April 28, 1992Assignee: NKK CorporationInventors: Masato Hirasaka, Yoshiaki Fujiwara
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Patent number: 5108565Abstract: A method of removing harmful gas from a refuse combustion exhaust gas. The refuse combustion exhaust gas, containing a harmful gas such as hydrogen chloride, is supplied to a reactor. Other steps include atomizing an alkaline material within the reactor, and applying radiation, such as an electron beam, to the refuse combustion exhaust gas, simultaneously with the atomizing of the alkaline material, thereby causing a reaction between the gas and the alkaline material, and recovering a salt produced by the reaction.Type: GrantFiled: September 4, 1990Date of Patent: April 28, 1992Assignees: Japan Atomic Energy Research Institute, NKK Corporation, Ebara CorporationInventors: Sueo Machi, Shoichi Sato, Okihiro Tokunaga, Yasushi Aoki, Shouichi Suda, Tsuneharu Miyachi, Yokichi Shibamura, Keita Kawamura, Ryoji Suzuki, Toru Agarida
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Patent number: 5104227Abstract: A three-dimensional curved surface shape measuring apparatus of the slit light rotating type. In accordance with a composite image .theta.(x', y') produced when a slit light is rotationally scanned with respect to a picture of an object to be measured and horizontal displacements x.sub.o and vertical displacement z.sub.o of an axis of rotation of the slit light with respect to an origin of a reference plane, a necessary computational processing is performed to determine a three-dimensional shape f(x, y) of the object surface which is free of distortion due to a perspective effect of a television camera.Type: GrantFiled: March 20, 1990Date of Patent: April 14, 1992Assignee: NKK CorporationInventors: Mitsuaki Uesugi, Masaichi Inomata
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Patent number: 5102478Abstract: For enabling the making of non-oriented magnetic steel strips by direct rolling, the amounts of AlN and MnS which precipitate on the way of the direct rolling are decreased to such a level that they do not affect the magnetic properties by regulting the Al and S amounts, and further unavoidable precipitating nitrides are precipitated coarsely as BN. With regard to the steel composition, the amount of C, Si and P are not only regulated, but also the amounts of Mn, Al, S and N are regulated from the above standpoint, and a proper amount of B is added if required. In addition, in regard to treatment conditions, in order to secure necessary finishing and coiling temperatures, the lower limit of the slab temperature at the starting time of the direct rolling is specified. Moreover, to promote refining of ferrite, the upper limit of the finishing temperature is specified, and also to prevent non-uniform recrystallization after coiling, the upper limit of the coiling temperature is specified.Type: GrantFiled: August 20, 1991Date of Patent: April 7, 1992Assignee: NKK CorporationInventors: Yoshihiro Hosoya, Akihiko Nishimoto, Toshiaki Urabe
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Patent number: 5102224Abstract: A three-dimensional curved surface shape measuring apparatus of the slit light linear scanning type. In accordance with a composite image u(x', y') produced by image composing means when a slit light is scanned over a surface of an object to be measured, a measured value or computed value u.sub.o (x', y') of a composite image with respect to a reference plane, a light projecting angle .theta. to the reference plane and a reference plane-television camera distance a, a necessary computational processing is performed to determine a three-dimensional curved surface shape f(x, y) of the surface of the object which is free of any distortions due to a perspective effect of the television camera.Type: GrantFiled: March 20, 1990Date of Patent: April 7, 1992Assignee: NKK CorporationInventors: Mitsuaki Uesugi, Masaichi Inomata
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Patent number: 5102223Abstract: A method and apparatus for measuring a three-dimensional curved surface shape based on a new measuring principle that a surface of an object to be measured is coded with information relating to a slit light which is used as a medium and moved or rotated at a constant speed. The manner in which a linear reflected pattern of the slit light is moved over the surface of the object to be measured is picked up by a television camera to form a composite image in which a value of each of picture elements in the image is represented by information relating to the slit light, e.g., a position, time or projection angle of the slit light at an instant that the slit light passes through one of positions on the object surface corresponding to that picture element.Type: GrantFiled: February 7, 1998Date of Patent: April 7, 1992Assignee: NKK CorporationInventors: Mitsuaki Uesugi, Masaichi Inomata, Isamu Komine
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Patent number: 5102043Abstract: A method for producing snow comprises producing a group of waterdrops by jetting water or water together with compressed air from a nozzle into the atmosphere of 0.degree. C. or less, and freezing the group of waterdrops jetted by applying ultrasonic waves to the group of waterdrops. An apparatus for producing snow comprises a jetting apparatus for producing a group of waterdrops by jetting water or water together with compressed air into the atmosphere of 0.degree. C. or less, and an ultrasonic wave generator for applying ultrasonic waves to the group of waterdrops jetted by the jetting apparatus.Type: GrantFiled: February 26, 1991Date of Patent: April 7, 1992Assignee: NKK CorporationInventors: Masanori Inoue, Susumu Kishi, Koji Ishihara, Akira Hagiwara
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Patent number: 5102044Abstract: A method for artificially producing snow, which is used for an indoor skiing facility. The method comprises maintaining an inside temperature of the indoor skiing facility of 0.degree. C. or less and blowing air and water with an air-water ratio of 300 to 3000 Nm.sup.3 /m.sup.3 in volume from a plurality of two-fluid spraying nozzles to generate and spread waterdrops of a particle size of 5 to 200 .mu.m, into the indoor skiing facility. The spray nozzles are disposed adjacent an upper portion of a cover enclosure of the indoor skiing facility. An apparatus for artificially producing snow. The apparatus comprising an indoor skiing facility having a floor and a cover enclosure comprising a ceiling and side walls. The cover enclosure and the floor are made from an insulating material. Holes are provided for blowing cold air into the indoor skiing facilities. The holes for blowing air are disposed adjacent an upper portion of the cover enclosure.Type: GrantFiled: February 12, 1991Date of Patent: April 7, 1992Assignee: NKK CorporationInventors: Masanori Inoue, Susumu Kishi, Katsutoshi Harima