Patents by Inventor Kazuya Kuwahara
Kazuya Kuwahara has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11961677Abstract: A capacitor module includes a capacitor element, a plurality of connection terminals for electrically connecting the capacitor element to a semiconductor module and a power supply that are another equipment, and an exterior coating that includes a resin film having electrical insulating property and wraps the capacitor element except the plurality of connection terminals.Type: GrantFiled: July 21, 2022Date of Patent: April 16, 2024Assignee: DENSO CORPORATIONInventors: Mamoru Kuwahara, Yuta Hashimoto, Kazuya Takeuchi
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Publication number: 20170263386Abstract: A negative electrode material for a power storage device contains a single-phase porous carbon material capable of electrochemically occluding and releasing lithium ions, the single-phase porous carbon material has a BET specific surface area of not less than 100 m2/g, and a cumulative volume of pores having a pore diameter of 2 nm to 50 nm in a pore diameter distribution of the single-phase porous carbon material is not less than 25% of a total pore volume.Type: ApplicationFiled: August 28, 2015Publication date: September 14, 2017Inventors: Shinji Ishikawa, Kazuya Kuwahara, Takahiro Saito
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Publication number: 20150251945Abstract: An optical fiber manufacturing method includes a drawing step and a slow cooling step. In the slow cooling step, an optical fiber passes through a heating furnace having a temperature which is set such that in at least 70% of a region from a first position at which a glass outer diameter of the optical fiber becomes less than 500% of a final outer diameter to a second position at which a temperature T of the optical fiber becomes 1400° C., an actual temperature of the optical fiber is within ±100° C. of a target temperature Tt(n) for each position n. The target temperature Tt(n) is a temperature at which a fictive temperature Tf(n+1) of a core at a position n+1 determined by calculation using the recurrence formula “Tf(n+1)=T(n)+(Tf(n)?T(n))exp(??t(T(n)))” starting from a fictive temperature Tf(0) of the optical fiber at the first position n=0 is lowest.Type: ApplicationFiled: September 24, 2013Publication date: September 10, 2015Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Tetsuya Nakanishi, Tatsuya Konishi, Kazuya Kuwahara
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Patent number: 9128236Abstract: An inexpensive low-attenuation optical fiber 1 suitable for use as an optical transmission line in an optical access network is a silica based glass optical fiber and includes a core 11 including the center axis, an optical cladding 12 surrounding the core, and a jacket 13 surrounding the optical cladding. The core contains GeO2 and has a relative refractive index difference ?core, based on the optical cladding, greater than or equal to 0.35% and less than or equal to 0.50% and has a refractive index volume v greater than or equal to 0.045 ?m2 and less than or equal to 0.095 ?m2. The jacket has a relative refractive index difference ?J greater than or equal to 0.03% and less than or equal to 0.20%. Glass constituting the core has a fictive temperature higher than or equal to 1400° C. and lower than or equal to 1590° C. Residual stress in the core is compressive stress that has an absolute value greater than or equal to 5 MPa.Type: GrantFiled: February 20, 2015Date of Patent: September 8, 2015Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Tetsuya Nakanishi, Tatsuya Konishi, Kazuya Kuwahara
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Publication number: 20150239740Abstract: A method for fabricating a porous carbon is provided. The method comprises the steps of: exposing a metal carbide to a heated atmosphere of a first gas to produce a porous carbon material and a metal chloride, the metal carbide containing a first metal and carbon, the first gas containing chlorine gas, and the metal chloride containing the first metal and chlorine; reacting the metal chloride with a second gas in a heated atmosphere to produce a metal oxide and a third gas, the second gas containing oxygen gas, the metal oxide containing the first metal and oxygen, and the third gas containing chlorine gas; and recovering chlorine gas from the third gas, the chlorine gas recovered being used as the chlorine gas for the first gas.Type: ApplicationFiled: October 15, 2013Publication date: August 27, 2015Inventors: Shinji Ishikawa, Kazuya Kuwahara
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Publication number: 20150160410Abstract: An inexpensive low-attenuation optical fiber 1 suitable for use as an optical transmission line in an optical access network is a silica based glass optical fiber and includes a core 11 including the center axis, an optical cladding 12 surrounding the core, and a jacket 13 surrounding the optical cladding. The core contains GeO2 and has a relative refractive index difference ?core, based on the optical cladding, greater than or equal to 0.35% and less than or equal to 0.50% and has a refractive index volume v greater than or equal to 0.045 ?m2 and less than or equal to 0.095 ?m2. The jacket has a relative refractive index difference ?J greater than or equal to 0.03% and less than or equal to 0.20%. Glass constituting the core has a fictive temperature higher than or equal to 1400° C. and lower than or equal to 1590° C. Residual stress in the core is compressive stress that has an absolute value greater than or equal to 5 MPa.Type: ApplicationFiled: February 20, 2015Publication date: June 11, 2015Inventors: Tetsuya NAKANISHI, Tatsuya KONISHI, Kazuya KUWAHARA
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Patent number: 8989545Abstract: An inexpensive low-attenuation optical fiber 1 suitable for use as an optical transmission line in an optical access network is a silica based glass optical fiber and includes a core 11 including the center axis, an optical cladding 12 surrounding the core, and a jacket 13 surrounding the optical cladding. The core contains GeO2 and has a relative refractive index difference ?core, based on the optical cladding, greater than or equal to 0.35% and less than or equal to 0.50% and has a refractive index volume v greater than or equal to 0.045 ?m2 and less than or equal to 0.095 ?m2. The jacket has a relative refractive index difference ?J greater than or equal to 0.03% and less than or equal to 0.20%. Glass constituting the core has a fictive temperature higher than or equal to 1400° C. and lower than or equal to 1590° C. Residual stress in the core is compressive stress that has an absolute value greater than or equal to 5 MPa.Type: GrantFiled: October 25, 2012Date of Patent: March 24, 2015Assignee: Sumitomo Electric Industries, Ltd.Inventors: Tetsuya Nakanishi, Tatsuya Konishi, Kazuya Kuwahara
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Patent number: 8687936Abstract: Provided is an inexpensive low-loss optical fiber suitably used in an optical transmission network. An optical fiber includes a core, an optical cladding, and a jacket. The core has a relative refractive index difference between 0.2% and 0.32% and has a refractive index volume between 9%·?m2 and 18%·?m2. The jacket has a relative refractive index difference between 0.03% and 0.20%. Glass constituting the core has a fictive temperature between 1400° C. and 1560° C. Stress remaining in the core is compressive stress. A cutoff wavelength measured on a fiber having a length of 2 m is 1300 nm or more and a cutoff wavelength measured on a fiber having a length of 100 m is 1500 nm or less. An effective area at a wavelength of 1550 nm is 110 ?m2 or more. A attenuation at a wavelength of 1550 nm is 0.19 dB/km or less.Type: GrantFiled: December 6, 2012Date of Patent: April 1, 2014Assignee: Sumitomo Electric Industries, Ltd.Inventors: Tetsuya Nakanishi, Tatsuya Konishi, Kazuya Kuwahara
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Publication number: 20140056596Abstract: An inexpensive low-attenuation optical fiber 1 suitable for use as an optical transmission line in an optical access network is a silica based glass optical fiber and includes a core 11 including the center axis, an optical cladding 12 surrounding the core, and a jacket 13 surrounding the optical cladding. The core contains GeO2 and has a relative refractive index difference ?core, based on the optical cladding, greater than or equal to 0.35% and less than or equal to 0.50% and has a refractive index volume v greater than or equal to 0.045 ?m2 and less than or equal to 0.095 ?m2. The jacket has a relative refractive index difference ?J greater than or equal to 0.03% and less than or equal to 0.20%. Glass constituting the core has a fictive temperature higher than or equal to 1400° C. and lower than or equal to 1590° C. Residual stress in the core is compressive stress that has an absolute value greater than or equal to 5 MPa.Type: ApplicationFiled: October 25, 2012Publication date: February 27, 2014Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Tetsuya Nakanishi, Tatsuya Konishi, Kazuya Kuwahara
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Publication number: 20130064513Abstract: An optical fiber has a plurality of holes in a cladding around a core, and has a high failure strength and small transmission loss. The core is made of glass. The cladding surrounds the core, and the holes are formed in the cladding so as to extend along a central axis of the fiber. The holes are formed with constant intervals therebetween along a circle centered on the core, and each hole has a substantially circular cross section. The cladding is sectioned into two claddings. A residual stress in an inner region that is inside a circumcircle of the holes is a compressive stress.Type: ApplicationFiled: August 24, 2012Publication date: March 14, 2013Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Takuji NAGASHIMA, Toshiki Taru, Kazuya Kuwahara
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Patent number: 8346041Abstract: The present invention relates to an optical communications system that allows improving OSNR while suppressing the power increase of pumping light for distributed Raman amplification. In the optical communications system, an optical fiber is laid in a transmission section between a transmitter station (or repeater station) and a receiver station (or repeater station), and optical signals are transmitted from the transmitter station to the receiver station via the optical fiber. In the optical communications system, pumping light for Raman amplification, outputted by a pumping light source provided in the receiver station, is fed into the optical fiber via an optical coupler, and the optical signals are distributed-Raman-amplified in the optical fiber. The transmission loss and the effective area of the optical fiber satisfy, at the wavelength of 1550 nm, a predetermined relationship.Type: GrantFiled: February 13, 2012Date of Patent: January 1, 2013Assignee: Sumitomo Electric Industries, Ltd.Inventors: Eisuke Sasaoka, Kazuya Kuwahara
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Publication number: 20120236295Abstract: A method of measuring the bending performance of an optical fiber in a simple manner is provided. Power P1 of light emitted from one end of the optical fiber when light is incident onto the other end of the optical fiber is measured under conditions where the optical fiber 1 is wound at a constant pitch by one layer on the circumferential side of a mandrel 2 and the overall circumference of the optical fiber 1 thus wound is covered with an index matching sheet 5. The refractive index of the index matching sheet 5 substantially matches with the refractive index of resin of the outermost layer of the optical fiber 1.Type: ApplicationFiled: March 12, 2012Publication date: September 20, 2012Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Tetsuya Nakanishi, Toshiki Taru, Takuji Nagashima, Tatsuya Konishi, Kazuya Kuwahara, Makoto Ichikawa
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Publication number: 20120230639Abstract: An easily manufacturable optical fiber that has desired properties includes a core region made of a glass, a cladding region made of a glass surrounding the core region and having a first viscosity at a drawing temperature, and a jacket region made of a glass surrounding the cladding region and having a second viscosity that is lower than the first viscosity at the drawing temperature. A plurality of holes that are surrounded by the glass of the cladding region and the glass of the jacket region are circumferentially arranged in a cross section that is perpendicular to a fiber axis and extend along the fiber axis, and 50% or more of the glass surrounding each of the plurality of holes is the glass of the cladding region.Type: ApplicationFiled: March 9, 2012Publication date: September 13, 2012Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Toshiki TARU, Takuji NAGASHIMA, Kazuya KUWAHARA
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Publication number: 20120148258Abstract: The present invention relates to an optical communications system that allows improving OSNR while suppressing the power increase of pumping light for distributed Raman amplification. In the optical communications system, an optical fiber is laid in a transmission section between a transmitter station (or repeater station) and a receiver station (or repeater station), and optical signals are transmitted from the transmitter station to the receiver station via the optical fiber. In the optical communications system, pumping light for Raman amplification, outputted by a pumping light source provided in the receiver station, is fed into the optical fiber via an optical coupler, and the optical signals are distributed-Raman-amplified in the optical fiber. The transmission loss and the effective area of the optical fiber satisfy, at the wavelength of 1550 nm, a predetermined relationship.Type: ApplicationFiled: February 13, 2012Publication date: June 14, 2012Inventors: Eisuke SASAOKA, Kazuya Kuwahara
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Patent number: 8145024Abstract: The present invention relates to an optical communications system that allows improving OSNR while suppressing the power increase of pumping light for distributed Raman amplification. In the optical communications system, an optical fiber is laid in a transmission section between a transmitter station (or repeater station) and a receiver station (or repeater station), and optical signals are transmitted from the transmitter station to the receiver station via the optical fiber. In the optical communications system, pumping light for Raman amplification, outputted by a pumping light source provided in the receiver station, is fed into the optical fiber via an optical coupler, and the optical signals are distributed-Raman-amplified in the optical fiber. The transmission loss and the effective area of the optical fiber satisfy, at the wavelength of 1550 nm, a predetermined relationship.Type: GrantFiled: August 5, 2010Date of Patent: March 27, 2012Assignee: Sumitomo Electric Industries, Ltd.Inventors: Eisuke Sasaoka, Kazuya Kuwahara
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Publication number: 20110044700Abstract: The present invention relates to an optical communications system that allows improving OSNR while suppressing the power increase of pumping light for distributed Raman amplification. In the optical communications system, an optical fiber is laid in a transmission section between a transmitter station (or repeater station) and a receiver station (or repeater station), and optical signals are transmitted from the transmitter station to the receiver station via the optical fiber. In the optical communications system, pumping light for Raman amplification, outputted by a pumping light source provided in the receiver station, is fed into the optical fiber via an optical coupler, and the optical signals are distributed-Raman-amplified in the optical fiber. The transmission loss and the effective area of the optical fiber satisfy, at the wavelength of 1550 nm, a predetermined relationship.Type: ApplicationFiled: August 5, 2010Publication date: February 24, 2011Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: EISUKE SASAOKA, KAZUYA KUWAHARA
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Publication number: 20100111486Abstract: The present invention relates to a dispersion compensating module having a configuration that can effectively suppress high-speed fluctuations in the polarization state of light even when being imparted with impact or vibration. In the dispersion compensating module, a dispersion compensating optical fiber is fixed while being wound around the barrel of a bobbin, and the bobbin is fixed in the inside of a housing via a buffer that absorbs impact or vibration. The bobbin corresponds to a holder holding the dispersion compensating optical fiber fixed in a state of coil. The housing corresponds to a struct fixing the holder. The buffer fills a space between the housing and the bobbin on which the dispersion compensating optical fiber is coiled.Type: ApplicationFiled: November 3, 2009Publication date: May 6, 2010Applicant: Sumitomo Electric Industries, Ltd.Inventors: Tetsuya HAYASHI, Eisuke SASAOKA, Kazuya KUWAHARA, Takashi SASAKI, Yasushi KOYANO, Fumiyoshi OHKUBO, Shinjiro HAGIHARA
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Publication number: 20060138271Abstract: It is an object of the present invention to provide an apparatus and method for winding a wire which are simple in structure and in which spring of the wire out of an annular guide is prevented by accommodating a cut terminal portion of the wire in the annular guide which is disposed movably toward one end of a take-up bobbin. The annular guide (20b) is disposed so that it is capable of covering one of the collars of the take-up bobbin (3) for the wire. The annular guide (20b) has a notch (24) for guiding the wire and an inner peripheral surface (25) having an inner diameter gradually increasing in a direction remote away from the bobbin. The annular guide (20b) may be formed in the shape so that it has an engagement portion (26) for preventing the spring of the wire out of the bobbin.Type: ApplicationFiled: April 19, 2004Publication date: June 29, 2006Inventors: Takashi Yamazaki, Kazuya Kuwahara
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Publication number: 20060101861Abstract: A drawing apparatus 1 comprises a drawing furnace 11, a heating furnace 21, and a resin curing section 31. An optical fiber 3 drawn upon heating in the drawing furnace 11 is sent to a heating furnace 21, where a predetermined part of the optical fiber 3 is annealed at a predetermined cooling rate. The temperature of a heater 22 of the heating furnace 21 at the furnace center is set to a temperature within the range from 1200 to 1600° C. Thereafter, the optical fiber 3 is coated with a UV resin liquid 52 by a coating die 51, and the UV resin 52 is cured in the resin curing section 31, so as to yield a coated optical fiber 4.Type: ApplicationFiled: October 7, 2005Publication date: May 18, 2006Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Katsuya Nagayama, Tatsuhiko Saitoh, Yuichi Ohga, Kazuya Kuwahara
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Patent number: 6935139Abstract: The method of manufacturing an optical fiber in accordance with the present invention comprises a step of yielding an optical fiber by drawing an optical fiber preform softened upon heating, wherein a temperature at which the optical fiber preform is softened is at least 1800° C., whereas the optical fiber preform or optical fiber has a glass cooling rate of 4000° C./sec or less when attaining a temperature of 1800° C.Type: GrantFiled: May 14, 2002Date of Patent: August 30, 2005Assignee: Sumitomo Electric IndustriesInventors: Katsuya Nagayama, Kazuya Kuwahara, Takayuki Shimazu