Patents by Inventor Takami Suzuki
Takami Suzuki 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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Publication number: 20230308035Abstract: (1) A motor control device of the present invention includes a magnetic-flux command value generator and a current-command value generator. The magnetic-flux command value generator is configured to generate a magnetic-flux command value based on a torque-command value. The current-command value generator is configured to generate a current-command value on the basis of the magnetic-flux command value. The magnetic-flux command value generator includes a magnetic-flux command calculator, a feedback-value calculator, a magnetic-flux compensation value calculator, a magnetic-flux command value calculator, and a control-gain changer.Type: ApplicationFiled: March 28, 2023Publication date: September 28, 2023Inventors: Takami SUZUKI, Kohei ONISHI, Tomoyuki DANSAKO, Tomofumi HAYASHI, Satoshi FUJISHIRO, Yoshihiro ITO
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Patent number: 11735995Abstract: A power conversion device having a multi-phase converter in which a plurality of chopper circuits each including a switching element and a reactor connected to the switching element are connected in parallel is provided. The power conversion device includes a single current sensor that is provided on a primary side of the chopper circuit, and detects a phase current flowing through each of the reactors when the switching elements are in both an on state and an off state, and a drift current detection unit configured to detect a drift current of a phase current in the multi-phase converter on the basis of the phase current detected by the current sensor, wherein the current sensor detects a phase current such that directions of phase currents flowing through each of the reactors are the same as each other.Type: GrantFiled: June 4, 2019Date of Patent: August 22, 2023Assignee: HITACHI ASTEMO, LTD.Inventors: Takami Suzuki, Yuta Nakamura, Kazunari Kurokawa, Takuma Kato
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Patent number: 11705845Abstract: This motor control device includes a vector control unit. The vector control unit includes: a current control unit that calculates a before-compensation d-axis voltage command value and a before-compensation q-axis voltage command value; a first non-interference control unit that calculates a first d-axis non-interference compensation value on the basis of a q-axis current command value to compensate for the before-compensation d-axis voltage command value and calculates a first q-axis non-interference compensation value on the basis of a d-axis current command value to compensate for the before-compensation q-axis voltage command value; and a second non-interference control unit that cancels out an interference component of a d-axis current generated in a specific rotation range of a motor with a q-axis current and an interference component of the q-axis current generated in the specific rotation range with the d-axis current by using a variable integral gain varying depending on a motor rotation speed.Type: GrantFiled: May 20, 2022Date of Patent: July 18, 2023Assignee: HITACHI ASTEMO, LTD.Inventor: Takami Suzuki
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Publication number: 20220385219Abstract: This motor control device includes a vector control unit. The vector control unit includes: a current control unit that calculates a before-compensation d-axis voltage command value and a before-compensation q-axis voltage command value; a first non-interference control unit that calculates a first d-axis non-interference compensation value on the basis of a q-axis current command value to compensate for the before-compensation d-axis voltage command value and calculates a first q-axis non-interference compensation value on the basis of a d-axis current command value to compensate for the before-compensation q-axis voltage command value; and a second non-interference control unit that cancels out an interference component of a d-axis current generated in a specific rotation range of a motor with a q-axis current and an interference component of the q-axis current generated in the specific rotation range with the d-axis current by using a variable integral gain varying depending on a motor rotation speed.Type: ApplicationFiled: May 20, 2022Publication date: December 1, 2022Inventor: Takami SUZUKI
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Patent number: 11489458Abstract: This multi-phase converter control device performs PWM control on driving of a multi-phase converter. The multi-phase converter is configured such that a plurality of converters connected to each other in parallel have reactors, and the reactors are magnetically coupled with each other and step up an input voltage to generate a step-up voltage. This multi-phase converter control device includes a feedback control unit configured to perform feedback control such that the step-up voltage is a target voltage, a PWM control unit configured to generate a PWM signal on the basis of a voltage command value output from the feedback control unit, and a drive unit configured to drive the multi-phase converter on the basis of the PWM signal. The feedback control unit calculates a step-up ratio of the multi-phase converter and changes a control gain in the feedback control on the basis of the step-up ratio.Type: GrantFiled: December 15, 2020Date of Patent: November 1, 2022Assignee: HITACHI ASTEMO, LTD.Inventor: Takami Suzuki
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Patent number: 11456685Abstract: The present motor control device includes an inverter, a converter, and a control device. The control device has a rotation speed calculation unit that calculates a rotation speed of a motor; an optimum voltage calculation unit that calculates an optimum input voltage; a minimum voltage calculation unit that calculates a minimum input voltage required to operate the motor at a motor operating point; and a target value setting unit that sets either one of the optimum input voltage and the minimum input voltage as a target input voltage. In a case in which the set target torque exceeds a predetermined value, the target value setting unit sets the minimum input voltage lower than the optimum input voltage as the target input voltage.Type: GrantFiled: December 22, 2020Date of Patent: September 27, 2022Assignee: HITACHI ASTEMO, LTD.Inventors: Shogo Tokita, Kazunari Kurokawa, Masahiro Shimada, Yuta Nakamura, Takami Suzuki
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Patent number: 11362597Abstract: The present power control device includes an inverter, a step-up/down converter, a first capacitor, a second capacitor, and a control device. The step-up/down converter includes an upper arm and a lower arm that are switching elements, and a reactor that has a first end and a second end, the first end being connected to the first capacitor, and the second end being connected between the upper arm and the lower arm. The control device is configured to fix the lower arm in an off state and control the upper arm such that the upper arm switches at a predetermined duty ratio.Type: GrantFiled: September 30, 2020Date of Patent: June 14, 2022Assignee: HITACHI ASTEMO, LTD.Inventors: Nobukatsu Yamaguchi, Yuta Nakamura, Takami Suzuki
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Publication number: 20210281195Abstract: The present motor control device includes an inverter, a converter, and a control device. The control device has a rotation speed calculation unit that calculates a rotation speed of a motor; an optimum voltage calculation unit that calculates an optimum input voltage; a minimum voltage calculation unit that calculates a minimum input voltage required to operate the motor at a motor operating point; and a target value setting unit that sets either one of the optimum input voltage and the minimum input voltage as a target input voltage. In a case in which the set target torque exceeds a predetermined value, the target value setting unit sets the minimum input voltage lower than the optimum input voltage as the target input voltage.Type: ApplicationFiled: December 22, 2020Publication date: September 9, 2021Inventors: Shogo TOKITA, Kazunari KUROKAWA, Masahiro SHIMADA, Yuta NAKAMURA, Takami SUZUKI
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Publication number: 20210281192Abstract: This multi-phase converter control device performs PWM control on driving of a multi-phase converter. The multi-phase converter is configured such that a plurality of converters connected to each other in parallel have reactors, and the reactors are magnetically coupled with each other and step up an input voltage to generate a step-up voltage. This multi-phase converter control device includes a feedback control unit configured to perform feedback control such that the step-up voltage is a target voltage, a PWM control unit configured to generate a PWM signal on the basis of a voltage command value output from the feedback control unit, and a drive unit configured to drive the multi-phase converter on the basis of the PWM signal. The feedback control unit calculates a step-up ratio of the multi-phase converter and changes a control gain in the feedback control on the basis of the step-up ratio.Type: ApplicationFiled: December 15, 2020Publication date: September 9, 2021Inventor: Takami SUZUKI
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Publication number: 20210159799Abstract: A power conversion device having a multi-phase converter in which a plurality of chopper circuits each including a switching element and a reactor connected to the switching element are connected in parallel is provided.Type: ApplicationFiled: June 4, 2019Publication date: May 27, 2021Inventors: Takami SUZUKI, Yuta NAKAMURA, Kazunari KUROKAWA, Takuma KATO
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Publication number: 20210104956Abstract: The present power control device includes an inverter, a step-up/down converter, a first capacitor, a second capacitor, and a control device. The step-up/down converter includes an upper arm and a lower arm that are switching elements, and a reactor that has a first end and a second end, the first end being connected to the first capacitor, and the second end being connected between the upper arm and the lower arm. The control device is configured to fix the lower arm in an off state and control the upper arm such that the upper arm switches at a predetermined duty ratio.Type: ApplicationFiled: September 30, 2020Publication date: April 8, 2021Inventors: Nobukatsu YAMAGUCHI, Yuta NAKAMURA, Takami SUZUKI
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Patent number: 10608535Abstract: A control device for a step-up converter which controls the step-up converter connected between a load and a DC power source, the control device includes a voltage control unit, a current command generation unit, a duty estimator, and a pole zero cancellation control unit. The voltage control unit performs a control arithmetic operation on the basis of a calculated value, obtained by performing a proportional arithmetic operation and an integration arithmetic operation on a difference between a voltage value on the load side and a voltage command value, and a value generated by the pole zero cancellation control unit. The current command generation unit generates a reactor current command value on the basis of an arithmetic result of the voltage control unit and a reciprocal of a duty estimation value.Type: GrantFiled: June 20, 2019Date of Patent: March 31, 2020Assignee: KEIHIN CORPORATIONInventor: Takami Suzuki
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Publication number: 20200044565Abstract: A control device for a step-up converter which controls the step-up converter connected between a load and a DC power source, the control device includes a voltage control unit, a current command generation unit, a duty estimator, and a pole zero cancellation control unit. The voltage control unit performs a control arithmetic operation on the basis of a calculated value, obtained by performing a proportional arithmetic operation and an integration arithmetic operation on a difference between a voltage value on the load side and a voltage command value, and a value generated by the pole zero cancellation control unit. The current command generation unit generates a reactor current command value on the basis of an arithmetic result of the voltage control unit and a reciprocal of a duty estimation value.Type: ApplicationFiled: June 20, 2019Publication date: February 6, 2020Inventor: Takami SUZUKI
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Patent number: 4986509Abstract: A seat lifter for a vehicular seat comprises spaced side base members; and front and rear lift mechanisms which are mounted on front and rear portions of the side base members for adjusting the heights of front and rear portions of a seat cushion respectively. Each lift mechanism comprises a pivot shaft extending across the side base members, brackets secured to the pivot shaft to rotate therewith, arm members pivotally connected to the brackets and connected to the seat cushion, a sector gear pivotally connected to one of the side base members and pivotally moved together with the pivot shaft, a pinion meshed with the sector gear, and a handling knob mounted on the side base member and having the pinion connected thereto.Type: GrantFiled: June 21, 1989Date of Patent: January 22, 1991Assignee: Ikeda Bussan Co., Ltd.Inventors: Takami Suzuki, Isamu Chinomi, Yuji Tanaka, Isao Kuwabara
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Patent number: 4943128Abstract: A mirror surface for deflecting an incident light beam is inclined to the axis of rotation and rotated for scanning the light beam. The incident light beam is applied to the mirror surface along the axis of rotation, and a reflected light beam is continuously deflected by the rotating mirror surface to scan a surface. When the incident light beam has an elliptical cross section in a direction normal to its optical axis, the cross-sectional shape of the reflected light beam varies due to the inclination of the mirror surface in response to rotation of the mirror surface. The varying shape of the reflected light beam obstructs proper reading and writing of an image with a light scanning device employing the above mirror surface. To avoid this problem, light beam shapers are provided in positions before and after the light beam is reflected by the mirror surface.Type: GrantFiled: October 28, 1987Date of Patent: July 24, 1990Assignee: Ricoh Company, Ltd.Inventors: Hiromi Takada, Takami Suzuki, Toshio Shiina, Keiji Okamoto, Takeshi Komurasaki, Satoru Yoshioka, Nobuo Sakuma, Tadashi Matsuura
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Patent number: 4875063Abstract: A laser printer or like electrostatic recording apparatus of the type developing an electrostatic latent image provided on a photoconductive drum by toner which is conveyed by a developing roller. Various devices of the apparatus including the photoconductive drum and developing roller are separated into an upper and a lower unit which are openable away from each other. A photoconductive drum assembly including the photoconductive element and a developing assembly including the developing roller are individually detachable from a body of the apparatus. Various measures are taken to enhance stable and safe operation, miniaturization, easy maintenance, operability, service life, and image quality.Type: GrantFiled: September 1, 1987Date of Patent: October 17, 1989Assignee: Ricoh Company, Ltd.Inventors: Hiroyuki Idenawa, Hideaki Mochimaru, Hajime Kanda, Nobuhiro Makita, Yoshiaki Tanaka, Takahiro Yagisita, Takanori Yamaki, Takeshi Motohashi, Masayoshi Miyamoto, Hisao Ishizu, Yasuhiro Sagawa, Tadaaki Kanno, Tomoo Sankoda, Hiroshi Hosokawa, Hideo Aoki, Takami Suzuki, Hiromi Takada, Toshio Shimazaki
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Patent number: 4874264Abstract: A hybrid printer includes at least one impact type print head and at least one non-impact type print head, which are selectively used to print not only graphic information but also character information. For example, the impact type print head may be a type wheel print head and the non-impact type print head may be a pen print head. The print heads are selectively magnetically coupled to the carriage drive belt.Type: GrantFiled: August 19, 1987Date of Patent: October 17, 1989Assignee: Ricoh Company, Ltd.Inventors: Takami Suzuki, Yoshikuni Tatara, Tomoyuki Moriya
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Patent number: 4416556Abstract: A type carrier for use in an impact-type printing machine to form an imprint of virtually the equal quality when used with either a flat hammer or a detentable, shaped hammer is provided. The present type carrier includes a hub and a plurality of fingers extending from the hub, each finger having a printing section which has a front surface provided with at least one type and a back surface having a novel structure. The back surface of the printing section includes at least one flat portion and at least a pair of sloped portions. Preferably, the sloped portions are defined such that they slope down oppositely from a plane common to or below the flat portion in the direction substantially perpendicular to the lengthwise direction of the finger.Type: GrantFiled: October 23, 1981Date of Patent: November 22, 1983Assignee: Ricoh Company, Ltd.Inventors: Nobuo Iwata, Koh Matsuhisa, Hiromi Takada, Takami Suzuki
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Patent number: 4363559Abstract: A print wheel mounting assembly for a serial printer comprising means for transmitting a torque from a rotary shaft to a print wheel, means for positioning the print wheel in the direction of its rotation and means for regulating the position of the print wheel axially thereof, whereby no special tool is required for mounting or detaching the print wheel on the rotary shaft.Type: GrantFiled: November 26, 1980Date of Patent: December 14, 1982Assignee: Ricoh Co., Ltd.Inventors: Takami Suzuki, Takashi Hasegawa
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Patent number: 4335970Abstract: Each of resilient tongues of a type wheel for use in a serial printing apparatus carries one or more type members. Each of the type members is provided with a curved or concave type face whose center of curvature lies on an axis of a paper supporting platen so that the type face comes into even and tight contact with the platen surface in a printing position. The curved type face is formed on a projection having a forward end which is tapered toward or away from a plane perpendicular to a rotary axis of the type wheel. Further, the each of the type members is provided with a back face which is formed on a back portion of the curved type face. The back face is driven by a hammer which is oriented in a predetermined direction toward the axis of the platen so as to be evenly and entirely engaged with a striking face of the hammer in the printing position. The back portion of the curved type face comprises a projection which is tapered toward or away from a plane perpendicular the rotary axis of the type wheel.Type: GrantFiled: June 24, 1980Date of Patent: June 22, 1982Assignee: Ricoh Company, Ltd.Inventors: Nobuo Iwata, Takami Suzuki