Patents by Inventor Toru Tamagawa
Toru Tamagawa 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: 7994483Abstract: To attain objects to reduce the spread of electrons as compared with a conventional one without degrading the multiplication factor of electrons; to provide a large electron multiplication factor; and to improve positional resolution, there is provided a gas electron multiplier using interaction between radiation and gas through photoelectric effects including: a chamber filled with gas and a single gas electron multiplication foil arranged in the chamber wherein the gas electron multiplication foil is made of a plate-like multilayer body composed by having a plate-like insulation layer made of a macromolecular polymer material having a thickness of around 100 ?m to 300 ?m and flat metal layers overlaid on both surfaces of the insulation layer, and the plate-like multilayer body is provided with a through-hole structure.Type: GrantFiled: March 1, 2007Date of Patent: August 9, 2011Assignees: Riken, The University of Tokyo, Scienergy Co., Ltd.Inventors: Toru Tamagawa, Satoshi Koshimuta, Hideki Hamagaki
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Publication number: 20090084972Abstract: To attain objects to reduce the spread of electrons as compared with a conventional one without degrading the multiplication factor of electrons; to provide a large electron multiplication factor; and to improve positional resolution, there is provided a gas electron multiplier using interaction between radiation and gas through photoelectric effects including: a chamber filled with gas and a single gas electron multiplication foil arranged in the chamber wherein the gas electron multiplication foil is made of a plate-like multilayer body composed by having a plate-like insulation layer made of a macromolecular polymer material having a thickness of around 100 ?m to 300 ?m and flat metal layers overlaid on both surfaces of the insulation layer, and the plate-like multilayer body is provided with a through-hole structure.Type: ApplicationFiled: March 1, 2007Publication date: April 2, 2009Applicants: RIKEN, THE UNIVERSITY OF TOKYO, SCIENERGY Co., LTD,Inventors: Toru Tamagawa, Satoshi Koshimuta, Hideki Hamagaki
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Patent number: 7481616Abstract: In a centrifugal fan the diameter of the impeller is rendered less than 20 mm, yet by rotating it under rotational conditions in which the centrifugal force along the impeller periphery is 10,000 m/s2 or more, the static pressure that the fan generates is heightened. At the same time, rendering the vane spacing a predetermined width or less reduces noise. Configuring in this way produces a small-scale, high-static-pressure, low-noise fan for cooling electronic devices. Furthermore, by mounting the centrifugal fan on a heatsink having densely arranged heat-dissipating projections a small-scale, high-cooling-capacity, quiet cooling device is realized.Type: GrantFiled: June 23, 2004Date of Patent: January 27, 2009Assignee: Nidec CorporationInventors: Toru Tamagawa, Yusuke Yoshida
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Patent number: 7364411Abstract: Small, high-performance centrifugal fan for cooling portable electronic devices. The centrifugal fan motor employs a cantilever-type impeller constituted by an impeller blade unit that includes a lower endwall portion at axial one end, having a wall surface for breaking the flow of air along the rotational axis, and an opening at the other axial end. The impeller is configured so that the radius r to the outer circumference of the impeller blade unit is smaller than the axial height h of the impeller. When an airflow that enters through the impeller opening is forced out towards outer periphery of the impeller blade unit, windage loss at the wall surface of the lower endwall portion of the impeller is reduced, which realizes high-efficiency cooling performance that complements motor performance.Type: GrantFiled: February 20, 2004Date of Patent: April 29, 2008Assignee: Nidec CorporationInventors: Toru Tamagawa, Yusuke Yoshida
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Patent number: 7264446Abstract: A tiny-diameter, lengthwise extensive impeller utilized in an ultra-small centrifugal fan is molded by an injection molding operation. In order to avert difficulties attendant on injection-molding ultra-miniature parts, the thickness and length of a reinforcing ring on the tip of the impeller are set to within predetermined ranges. Further, the thickness of each of the vanes that constitute the impeller is made maximum where they join to the impeller ring section.Type: GrantFiled: March 31, 2005Date of Patent: September 4, 2007Assignee: Nidec CorporationInventors: Yusuke Yoshida, Toru Tamagawa, Tomotsugu Sugiyama, Kazumi Takeshita
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Patent number: 7217087Abstract: A centrifugal fan comprises an impeller, a motor which is connected and rotates the impeller and a housing which has an intake and an air blowing port for housing the impeller. The impeller has a plurality of blades arranged on a circumference. The intake opens opposed to the right end (in FIG. 1) of the impeller. The air blowing port opens opposed to a side of the impeller. A gap enlarged portion, in which the distance between the outer circumference of the impeller and the inner face of the housing starts to increase at a point where the distance between the outer circumferential of the impeller and the surface of a nose portion is smallest therein, the nose portion being a region of the vicinity of an edge portion of the air blowing port, the edge portion being the closest side to the outer circumference of the impeller.Type: GrantFiled: March 28, 2005Date of Patent: May 15, 2007Assignee: Nidec CorporationInventors: Yusuke Yoshida, Toru Tamagawa, Tomotsugu Sugiyama, Kazumi Takeshita, Masayuki Aoki
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Publication number: 20060056964Abstract: In a centrifugal fan the diameter of the impeller is rendered less than 20 mm, yet by rotating it under rotational conditions in which the centrifugal force along the impeller periphery is 10,000 m/s2 or more, the static pressure that the fan generates is heightened. At the same time, rendering the vane spacing a predetermined width or less reduces noise. Configuring in this way produces a small-scale, high-static-pressure, low-noise fan for cooling electronic devices. Furthermore, by mounting the centrifugal fan on a heatsink having densely arranged heat-dissipating projections a small-scale, high-cooling-capacity, quiet cooling device is realized.Type: ApplicationFiled: June 23, 2004Publication date: March 16, 2006Applicant: NIDEC CORPORATIONInventors: Toru Tamagawa, Yusuke Yoshida
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Publication number: 20060013684Abstract: Small, high-performance centrifugal fan for cooling portable electronic devices. The centrifugal fan motor employs a cantilever-type impeller constituted by an impeller blade unit that includes a lower endwall portion at axial one end, having a wall surface for breaking the flow of air along the rotational axis, and an opening at the other axial end. The impeller is configured so that the radius r to the outer circumference of the impeller blade unit is smaller than the axial height h of the impeller. When an airflow that enters through the impeller opening is forced out towards outer periphery of the impeller blade unit, windage loss at the wall surface of the lower endwall portion of the impeller is reduced, which realizes high-efficiency cooling performance that complements motor performance.Type: ApplicationFiled: February 20, 2004Publication date: January 19, 2006Applicant: NIDEC CORPORATIONInventors: Toru Tamagawa, Yusuke Yoshida
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Publication number: 20050220613Abstract: A tiny-diameter, lengthwise extensive impeller utilized in an ultra-small centrifugal fan is molded by an injection molding operation. In order to avert difficulties attendant on injection-molding ultra-miniature parts, the thickness and length of a reinforcing ring on the tip of the impeller are set to within predetermined ranges. Further, the thickness of each of the vanes that constitute the impeller is made maximum where they join to the impeller ring section.Type: ApplicationFiled: March 31, 2005Publication date: October 6, 2005Applicant: NIDEC CORPORATIONInventors: Yusuke Yoshida, Toru Tamagawa, Tomotsugu Sugiyama, Kazumi Takeshita
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Publication number: 20050207887Abstract: A centrifugal fan comprises an impeller, a motor which is connected and rotates the impeller and a housing which has an intake and an air blowing port for housing the impeller. The impeller has a plurality of blades arranged on a circumference. The intake opens opposed to the right end (in FIG.1) of the impeller. The air blowing port opens opposed to a side of the impeller. A gap enlarged portion, in which the distance between the outer circumference of the impeller and the inner face of the housing starts to increase at a point where the distance between the outer circumferential of the impeller and the surface of a nose portion is smallest therein, the nose portion being a region of the vicinity of an edge portion of the air blowing port, the edge portion being the closest side to the outer circumference of the impeller.Type: ApplicationFiled: March 28, 2005Publication date: September 22, 2005Applicant: NIDEC CORPORATIONInventors: Yusuke Yoshida, Toru Tamagawa, Tomotsugu Sugiyama, Kazumi Takeshita, Masayuki Aoki
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Publication number: 20050042082Abstract: In a centrifugal fan the diameter of the impeller is rendered less than 20 mm, yet by rotating it under rotational conditions in which the centrifugal force along the impeller periphery is 10,000 m/s2 or more, the static pressure that the fan generates is heightened. At the same time, rendering the vane spacing a predetermined width or less reduces noise. Configuring in this way produces a small-scale, high-static-pressure, low-noise fan for cooling electronic devices. Furthermore, by mounting the centrifugal fan on a heatsink having densely arranged heat-dissipating projections a small-scale, high-cooling-capacity, quiet cooling device is realized.Type: ApplicationFiled: June 23, 2004Publication date: February 24, 2005Applicant: NIDEC CORPORATIONInventors: Toru Tamagawa, Yusuke Yoshida
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Publication number: 20040202540Abstract: Small, high-performance centrifugal fan for cooling portable electronic devices. The centrifugal fan motor employs a cantilever-type impeller constituted by an impeller blade unit that includes a lower endwall portion at axial one end, having a wall surface for breaking the flow of air along the rotational axis, and an opening at the other axial end. The impeller is configured so that the radius r to the outer circumference of the impeller blade unit is smaller than the axial height h of the impeller. When an airflow that enters through the impeller opening is forced out towards outer periphery of the impeller blade unit, windage loss at the wall surface of the lower endwall portion of the impeller is reduced, which realizes high-efficiency cooling performance that complements motor performance.Type: ApplicationFiled: February 20, 2004Publication date: October 14, 2004Applicant: NIDEC CORPORATIONInventors: Toru Tamagawa, Yusuke Yoshida
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Patent number: 4307428Abstract: A circuit breaker apparatus of high voltage direct currents is connected in series with an external circuit comprising an AC-DC converting device connected to an AC power supply and a DC reactor connected to the AC-DC converting device, and comprises a circuit breaker connected in series with the external circuit, a disconnecting switch connected to the circuit breaker, and a series circuit connected in parallel with the circuit breaker and constituted of a blocking capacitor and a primary winding in a transformer. A charge storage capacitor is connected to a secondary winding of the transformer through a starting switch and polarity changeover switch, and an AC power supply for charging is connected through a diode to the charge storage capacitor.Type: GrantFiled: August 28, 1979Date of Patent: December 22, 1981Assignee: Tokyo Shibaura Denki Kabushiki KaishaInventors: Satoru Yanabu, Toru Tamagawa, Susumu Nishiwaki
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Patent number: 3946179Abstract: A vacuum interrupter includes a small-sized, light-weight, rigid coil electrode located behind a main electrode having a plurality of straight slits provided therein and extending from the periphery toward the central portion thereof, wherein magnetic field is created in a direction perpendicular to the surface of the main electrode by arc current flowing through the coil electrode, thereby causing arc produced on the surface of the main electrode to be uniformly and stably distributed, while preventing weakening of the magnetic field by arc current flowing along the surface of the main electrode and eddy current developed on the main electrode by the magnetic field.Type: GrantFiled: September 10, 1974Date of Patent: March 23, 1976Assignee: Tokyo Shibaura Electric Co., Ltd.Inventors: Minoru Murano, Satoru Yanabu, Toru Tamagawa, Nobuyuki Takahashi, Hiroyuki Okumura, Hiroshi Ohhashi