Patents by Inventor Masayoshi Nakayama
Masayoshi Nakayama 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: 9696654Abstract: An image forming apparatus includes an image bearer, an image forming device, a toner concentration detector, a toner supply device, an image density detector, and a controller including a memory device. At a predetermined timing before image formation is started, the controller adjusts a developing potential to adjust an image density of a detection toner image on the image bearer and drives the toner supply device or the developing device to adjust a toner concentration in the developing device. After the image formation is started, the controller drives the toner supply device to adjust the toner concentration, and, in a predetermined sheet interval, adjusts the target concentration based on the image density of the detection toner image formed in a non-image area of the image bearer. When the toner concentration is higher than the target concentration plus a threshold, the controller suspends image formation and readjusts the developing potential.Type: GrantFiled: April 1, 2016Date of Patent: July 4, 2017Assignee: Ricoh Company, Ltd.Inventors: Masayoshi Nakayama, Takuma Higa, Hiroyuki Kunii, Masaki Sukesako, Kazuaki Kamihara, Yuichi Aizawa, Masahiro Katoh, Kohei Matsumoto
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Publication number: 20170003630Abstract: An image forming apparatus includes an image bearer, a transfer member, and a power source. The image bearer includes a plurality of layers. The transfer member forms a transfer nip between the image bearer and the transfer member. The power source outputs a transfer bias to transfer a toner image from the image bearer onto a recording sheet in the transfer nip. The transfer bias alternates between a transfer-side bias that causes the toner image to move from the image bearer to the recording sheet, and an opposite-side bias different from the transfer-side bias. A duty ratio of a time period, during which the opposite-side bias is output, relative to one cycle of a waveform, is greater than 50%.Type: ApplicationFiled: September 14, 2016Publication date: January 5, 2017Inventors: Tatsuya OHSUGI, Kenji SUGIURA, Jyunya SAKURABA, Hirokazu ISHII, Toshitaka YAMAGUCHI, Hiroyoshi HAGA, Naohiro KUMAGAI, Seiichi KOGURE, Junpei FUJITA, Yuuji WADA, Kazuki YOGOSAWA, Shinya TANAKA, Masayoshi NAKAYAMA
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Publication number: 20160372191Abstract: A nonvolatile semiconductor storage apparatus is provided. To a data node and a reference node, a first transistor and a second transistor are respectively connected. In a data state determining operation, in the case where voltage is applied to the data node and reference node, the first and second transistors operate as precharge transistors in a first operation mode, and operate as mirror transistors in a second operation mode. The first and second operation modes are switched.Type: ApplicationFiled: July 25, 2016Publication date: December 22, 2016Inventors: MASAYOSHI NAKAYAMA, YASUO MURAKUKI, TAKAFUMI MARUYAMA
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Patent number: 9500978Abstract: An image forming apparatus includes a first electric charging unit having an electric discharge wire to uniformly electrify a surface of the electrostatic latent image bearer, a second electric charging unit having a second electric discharge wire to execute a pre-electric charge removal electric charging process by electrifying the surface of the electrostatic latent image bearer subsequent to a transfer process to transfer a toner image, and a first electric charge removing device to diselectrify the surface of the electrostatic latent image bearer by irradiating it with electric charge removing light subsequent to the pre-electric charge removal electric charging process. The first electric charge removing device is disposed within an electric discharge region of the second electric discharge wire on a downstream side of an extreme upstream edge of the electric discharge region of the second electric discharge wire in a rotational direction of the electrostatic latent image bearer.Type: GrantFiled: July 8, 2015Date of Patent: November 22, 2016Assignee: RICOH COMPANY, LTD.Inventors: Masayoshi Nakayama, Takuma Higa, Hiroyuki Kunil, Masaki Sukesako, Kazuaki Kamihara, Masakazu Terao, Yuichi Aizawa, Masahiro Katoh, Kohei Matsumoto, Toshihiro Sugiyama
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Patent number: 9488931Abstract: An image forming apparatus includes a latent image bearer; a developing device containing two-component developer and including a developer bearer, a development voltage source, and a toner concentration detector; a toner supply device to supply toner to the developing device; a transfer device; and a controller to keep a toner concentration in the developer in the developing device at a target toner concentration during image formation. The controller executes forced toner consumption in which the developing device supplies the toner to the latent image bearer the toner at a predetermined forced toner consumption timing, while inhibiting the toner supply device from supplying toner. When the toner concentration falls to a prescribed toner density lower than the target toner concentration, the controller completes the forced toner consumption and executes a post-consumption toner supply operation.Type: GrantFiled: November 12, 2015Date of Patent: November 8, 2016Assignee: Ricoh Company, Ltd.Inventors: Makoto Yasuda, Jun Hitosugi, Takamasa Ozeki, Mutsuki Morinaga, Emiko Shiraishi, Wakana Itoh, Hitoshi Yamamoto, Takatsugu Komori, Kunio Hasegawa, Tadashi Kasai, Kazuaki Kamihara, Kazumi Kobayashi, Hiroyuki Kunii, Masaki Sukesako, Yuichi Aizawa, Masakazu Terao, Masayoshi Nakayama, Takuma Higa, Masahiro Katoh, Kohei Matsumoto
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Publication number: 20160291507Abstract: An image forming apparatus includes an image bearer, an image forming device, a toner concentration detector, a toner supply device, an image density detector, and a controller including a memory device. At a predetermined timing before image formation is started, the controller adjusts a developing potential to adjust an image density of a detection toner image on the image bearer and drives the toner supply device or the developing device to adjust a toner concentration in the developing device. After the image formation is started, the controller drives the toner supply device to adjust the toner concentration, and, in a predetermined sheet interval, adjusts the target concentration based on the image density of the detection toner image formed in a non-image area of the image bearer. When the toner concentration is higher than the target concentration plus a threshold, the controller suspends image formation and readjusts the developing potential.Type: ApplicationFiled: April 1, 2016Publication date: October 6, 2016Applicant: Ricoh Company, Ltd.Inventors: Masayoshi Nakayama, Takuma Higa, Hiroyuki Kunii, Masaki Sukesako, Kazuaki Kamihara, Yuichi Aizawa, Masahiro Katoh, Kohei Matsumoto
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Patent number: 9459564Abstract: An image forming apparatus includes an image bearer, a transfer member, and a power source. The image bearer includes a plurality of layers. The transfer member forms a transfer nip between the image bearer and the transfer member. The power source outputs a transfer bias to transfer a toner image from the image bearer onto a recording sheet in the transfer nip. The transfer bias alternates between a transfer-side bias that causes the toner image to move from the image bearer to the recording sheet, and an opposite-side bias different from the transfer-side bias. A duty ratio of a time period, during which the opposite-side bias is output, relative to one cycle of a waveform, is greater than 50%.Type: GrantFiled: October 13, 2015Date of Patent: October 4, 2016Assignee: Ricoh Company, Ltd.Inventors: Tatsuya Ohsugi, Kenji Sugiura, Jyunya Sakuraba, Hirokazu Ishii, Toshitaka Yamaguchi, Hiroyoshi Haga, Naohiro Kumagai, Seiichi Kogure, Junpei Fujita, Yuuji Wada, Kazuki Yogosawa, Shinya Tanaka, Masayoshi Nakayama
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Patent number: 9423746Abstract: An image forming apparatus includes a latent image bearer that carries a latent image and a developer carrier including a developer carrying member that carries a developer on a surface thereof. The developer carrier conveys the developer to a developing position opposite to the latent image bearer by moving the developer carrying member so as to develop the latent image carried by the latent image bearer. In a startup operation after a stop operation performed during a developing operation by the developer carrier, the developer carrying member is rotated for a predetermined time while the latent image bearer is set in a stopped state before starting a rotation.Type: GrantFiled: January 13, 2015Date of Patent: August 23, 2016Assignee: Ricoh Company, Ltd.Inventor: Masayoshi Nakayama
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Publication number: 20160147174Abstract: An image forming apparatus includes a latent image bearer; a developing device containing two-component developer and including a developer bearer, a development voltage source, and a toner concentration detector; a toner supply device to supply toner to the developing device; a transfer device; and a controller to keep a toner concentration in the developer in the developing device at a target toner concentration during image formation. The controller executes forced toner consumption in which the developing device supplies the toner to the latent image bearer the toner at a predetermined forced toner consumption timing, while inhibiting the toner supply device from supplying toner. When the toner concentration falls to a prescribed toner density lower than the target toner concentration, the controller completes the forced toner consumption and executes a post-consumption toner supply operation.Type: ApplicationFiled: November 12, 2015Publication date: May 26, 2016Inventors: Makoto YASUDA, Jun HITOSUGI, Takamasa OZEKI, Mutsuki MORINAGA, Emiko SHIRAISHI, Wakana ITOH, Hitoshi YAMAMOTO, Takatsugu KOMORI, Kunio HASEGAWA, Tadashi KASAI, Kazuaki KAMIHARA, Kazumi KOBAYASHI, Hiroyuki KUNll, Masaki SUKESAKO, Yuichi AIZAWA, Masakazu TERAO, Masayoshi NAKAYAMA, Takuma HIGA, Masahiro KATOH, Kohei MATSUMOTO
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Patent number: 9343115Abstract: A memory array includes a resistive memory cell array having a first cell transistor and a resistance change element connected in series and a reference cell array having a second cell transistor and a resistance element connected in series. The second cell transistor of the reference cell array is connected to a reference source line, and the resistance element is connected to a reference bit line. A dummy memory cell is connected to the reference bit line in the memory cell array, and both ends of a resistance change element of the dummy memory cell are short-circuited through the reference bit line.Type: GrantFiled: March 12, 2015Date of Patent: May 17, 2016Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.Inventors: Takanori Ueda, Kazuyuki Kouno, Yasuo Murakuki, Masayoshi Nakayama, Yuriko Ishitobi, Keita Takahashi
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Publication number: 20160109832Abstract: An image forming apparatus includes an image bearer, a transfer member, and a power source. The image bearer includes a plurality of layers. The transfer member forms a transfer nip between the image bearer and the transfer member. The power source outputs a transfer bias to transfer a toner image from the image bearer onto a recording sheet in the transfer nip. The transfer bias alternates between a transfer-side bias that causes the toner image to move from the image bearer to the recording sheet, and an opposite-side bias different from the transfer-side bias. A duty ratio of a time period, during which the opposite-side bias is output, relative to one cycle of a waveform, is greater than 50%.Type: ApplicationFiled: October 13, 2015Publication date: April 21, 2016Inventors: Tatsuya OHSUGI, Kenji SUGIURA, Jyunya SAKURABA, Hirokazu ISHll, Toshitaka YAMAGUCHI, Hiroyoshi HAGA, Naohiro KUMAGAI, Seiichi KOGURE, Junpei FUJITA, Yuuji WADA, Kazuki YOGOSAWA, Shinya TANAKA, Masayoshi NAKAYAMA
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Publication number: 20160026109Abstract: An image forming apparatus includes a first electric charging unit having an electric discharge wire to uniformly electrify a surface of the electrostatic latent image bearer, a second electric charging unit having a second electric discharge wire to execute a pre-electric charge removal electric charging process by electrifying the surface of the electrostatic latent image bearer subsequent to a transfer process to transfer a toner image, and a first electric charge removing device to diselectrify the surface of the electrostatic latent image bearer by irradiating it with electric charge removing light subsequent to the pre-electric charge removal electric charging process. The first electric charge removing device is disposed within an electric discharge region of the second electric discharge wire on a downstream side of an extreme upstream edge of the electric discharge region of the second electric discharge wire in a rotational direction of the electrostatic latent image bearer.Type: ApplicationFiled: July 8, 2015Publication date: January 28, 2016Applicant: RICOH COMPANY, LTD.Inventors: Masayoshi Nakayama, Takuma Higa, Hiroyuki Kunii, Masaki Sukesako, Kazuaki Kamihara, Masakazu Terao, Yuichi Aizawa, Masahiro Katoh, Kohei Matsumoto, Toshihiro Sugiyama
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Publication number: 20160004192Abstract: An image forming apparatus has a system speed of from 400 to 2,000 mm/sec and includes an endless intermediate transfer belt to transfer a sheet-shaped medium bearing an image formed of a toner. The intermediate transfer belt includes a first layer including at least a substrate; a second layer; and an electric resistance controlling material and has a surface resistivity of from 1×108 to 1×1013 ?/?, a volume resistivity of from 1×106 to 1×1012 ?·cm, and a surface roughness not greater than 50 ?m. The toner includes a mother particle which is surface-treated with a fluidizer, comprising a charge controlling agent and at least two external additives which are inorganic particulate materials and particulate polymers formed of polymeric particulate materials or thermosetting resins adhering to the surface of the mother particle.Type: ApplicationFiled: June 16, 2015Publication date: January 7, 2016Applicant: RICOH COMPANY, LTD.Inventors: Wakana Itoh, Hiroyuki Kunii, Masayoshi Nakayama, Kazuaki Kamihara, Takuma Higa
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Patent number: 9229399Abstract: An image forming apparatus includes multiple image forming units each including a latent image bearer and a developing device, a transfer device to transfer toner images from the latent image bearers onto a surface of endless rotary member, a cleaner to clean the surface of the endless rotary member, and a control unit to execute a forcible toner consumption process to forcibly consume degraded toner stored in applicable one or more developing devices. The forcible toner consumption process includes a step of forming a toner image formed for forced consumption in a non-image region of the latent image bearer with an amount of toner corresponding to a difference between an image area ratio of a developed image and a prescribed threshold when the image area ratio of the developed image is lower than the prescribed threshold.Type: GrantFiled: December 5, 2014Date of Patent: January 5, 2016Assignee: Ricoh Company, Ltd.Inventors: Kazuaki Kamihara, Toshihiro Sugiyama, Takuma Higa, Masayoshi Nakayama, Hiroyuki Kunii, Masaki Sukesako, Wakana Itoh
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Publication number: 20150348626Abstract: A memory array includes a plurality of memory cells arranged in a matrix, each memory cell including a cell transistor and a variable resistance element connected to an end of the cell transistor, and a cell transistor performance measuring cell including a MOS transistor. The cell transistor performance measuring cell is used to stabilize resistance values in a low resistance state and a high resistance state of the variable resistance element irrespective of variations in the cell transistor and thereby improve read characteristics and reliability characteristics of a nonvolatile semiconductor storage device.Type: ApplicationFiled: August 13, 2015Publication date: December 3, 2015Inventors: Masayoshi NAKAYAMA, Kazuyuki KOUNO, Reiji MOCHIDA, Keita TAKAHASHI
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Publication number: 20150198909Abstract: An image forming apparatus includes a latent image bearer that carries a latent image and a developer carrier including a developer carrying member that carries a developer on a surface thereof. The developer carrier conveys the developer to a developing position opposite to the latent image bearer by moving the developer carrying member so as to develop the latent image carried by the latent image bearer. In a startup operation after a stop operation performed during a developing operation by the developer carrier, the developer carrying member is rotated for a predetermined time while the latent image bearer is set in a stopped state before starting a rotation.Type: ApplicationFiled: January 13, 2015Publication date: July 16, 2015Applicant: RICOH COMPANY, LTD.Inventor: Masayoshi NAKAYAMA
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Publication number: 20150187393Abstract: A memory array includes a resistive memory cell array having a first cell transistor and a resistance change element connected in series and a reference cell array having a second cell transistor and a resistance element connected in series. The second cell transistor of the reference cell array is connected to a reference source line, and the resistance element is connected to a reference bit line. A dummy memory cell is connected to the reference bit line in the memory cell array, and both ends of a resistance change element of the dummy memory cell are short-circuited through the reference bit line.Type: ApplicationFiled: March 12, 2015Publication date: July 2, 2015Inventors: Takanori UEDA, Kazuyuki KOUNO, Yasuo MURAKUKI, Masayoshi NAKAYAMA, Yuriko ISHITOBI, Keita TAKAHASHI
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Publication number: 20150160599Abstract: An image forming apparatus includes multiple image forming units each including a latent image bearer and a developing device, a transfer device to transfer toner images from the latent image bearers onto a surface of endless rotary member, a cleaner to clean the surface of the endless rotary member, and a control unit to execute a forcible toner consumption process to forcibly consume degraded toner stored in applicable one or more developing devices. The forcible toner consumption process includes a step of forming a toner image formed for forced consumption in a non-image region of the latent image bearer with an amount of toner corresponding to a difference between an image area ratio of a developed image and a prescribed threshold thereof when the image area ratio of the developed image is lower than the prescribed threshold.Type: ApplicationFiled: December 5, 2014Publication date: June 11, 2015Inventors: Kazuaki KAMIHARA, Toshihiro SUGIYAMA, Takuma HIGA, Masayoshi NAKAYAMA, Hiroyuki KUNII, Masaki SUKESAKO, Wakana ITOH
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Patent number: 8718498Abstract: An image forming apparatus includes: an image forming unit that includes a developing unit with a developing roller to form an image using toner; a controller; and a detection unit that detects a plurality of toner patches formed at different densities on an image carrier by the image forming unit. The controller controls the image forming unit to form the toner patches on the image carrier so that each interval between the toner patches is equal to or greater than a length corresponding to a circumference length of the developing roller.Type: GrantFiled: March 7, 2011Date of Patent: May 6, 2014Assignee: Ricoh Company, LimitedInventor: Masayoshi Nakayama
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Patent number: 8711629Abstract: Bit lines connected to each nonvolatile memory cell are selected by corresponding selective transistors. A first drive circuit for driving the gate of one of the selective transistors receives a voltage selected by a first voltage switch, and a second drive circuit for driving the gate of the other selective transistor receives a voltage selected by a second voltage switch. A transistor constituting the first drive circuit is different in structure from a transistor constituting the second drive circuit.Type: GrantFiled: September 10, 2012Date of Patent: April 29, 2014Assignee: Panasonic CorporationInventors: Masayoshi Nakayama, Takashi Ono, Reiji Mochida