Patents by Inventor Fumihiro Shimizu
Fumihiro Shimizu 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: 20140365167Abstract: An angle detection device includes a vector generating unit that generates a vector based on the sine wave signals output by a plurality of sensors, a vector rotating unit that rotate the vector based on the vector and reference sine waves with different phases, a sign determining unit that determines whether the rotated vector is located in a positive direction or in a negative direction with respect to a predetermined reference angle and outputs a result of determination as a sign determination signal, and an angle counter that increments or decrements a count value of angular data of a predetermined bit length based on the sign determination signal, and outputs the count value as angular data. A deadband with a predetermined reference angle as a center is provided for a process performed by the sign determining unit to determine one of the positive direction and the negative direction.Type: ApplicationFiled: May 28, 2014Publication date: December 11, 2014Applicant: Ricoh Company, LimitedInventor: Fumihiro SHIMIZU
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Patent number: 8872453Abstract: A motor drive controller to control a motor via multiple sensors includes a first phase detector to compare respective differential pairs of the sensor signals from the same sensor to detect phases of the rotor, and output a first phase information signal; a second phase detector to compare a respective one of the multiple sensor signals with another sensor signal from the different sensor to detect the phases and output a second phase information signal; a phase divider to divide the phases, detected by the first and second phase detectors, into multiple predetermined phase intervals; a signal selector to select one of the multiple sensor signals in the multiple predetermined phase intervals; and a third phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a third phase information signal.Type: GrantFiled: October 23, 2012Date of Patent: October 28, 2014Assignee: Ricoh Company, Ltd.Inventors: Tomohiko Kamatani, Haruyuki Suzuki, Fumihiro Shimizu, Katsuhisa Furuse
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Patent number: 8866421Abstract: A motor drive controller to drive a motor, based on multiple sensors that generates multiple sensor signals corresponding to different positions of the rotor; including a first phase detector to compare a respective one of the multiple sensor signals with a paired sensor signal from the same sensor to detect phases of the rotor, and output a first phase information signal representing a first detected phase; a phase divider to divide the phases, detected by the first phase detector into multiple predetermined phase intervals; a signal selector to select one of the respective multiple sensor signals from the multiple sensors in the multiple predetermined phase interval; and a second phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a second phase information signal representing a second detected phase.Type: GrantFiled: October 23, 2012Date of Patent: October 21, 2014Assignee: Ricoh Company, Ltd.Inventors: Tomohiko Kamatani, Haruyuki Suzuki, Fumihiro Shimizu, Katsuhisa Furuse
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Patent number: 8860346Abstract: Disclosed is an angle detection device including plural sensors that output corresponding sinusoidal signals, wherein each of the sinusoidal signals varies sinusoidally depending on a rotational angle of a rotor of a motor, and each of the sinusoidal signals has a phase that depends on a position of the corresponding sensor; a vector generating unit that generates a vector represented by a result of mutually operating at least two of the sinusoidal signals; a vector rotation unit that rotates the vector by operating the vector and reference sine waves having corresponding phases; and an angle search unit that causes the vector rotation unit to sequentially rotate the vector until a phase of the vector becomes a predetermined phase, and that detects an angle between the vector prior to being rotated and the predetermined phase as the rotational angle of the rotor of the motor.Type: GrantFiled: October 11, 2012Date of Patent: October 14, 2014Assignee: Ricoh Company, Ltd.Inventors: Fumihiro Shimizu, Haruyuki Suzuki, Tomohiko Kamatani, Katsuhisa Furuse
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Publication number: 20130325187Abstract: A motor control device includes: a unit configured to generate a target rotation position information of a first driving motor based on target rotation position signals indicating a target rotation position of a second driving motor being replaced with the first driving motor; a unit configured to generate a speed predicting of the first driving motor; a unit configured to detect a rotation position of the first driving motor; a unit configured to generate an actual position information of the first driving motor; a unit configured to generate an actual speed of the first driving motor; a unit configured to correct an error between the target rotation position and the actual rotation position of the first driving motor; a unit configured to generate a speed error signal; a unit configured to generate a speed control signals of the first driving motor; and a unit configured to output a drive voltage.Type: ApplicationFiled: May 29, 2013Publication date: December 5, 2013Inventors: Fumihiro SHIMIZU, Takuya Murata
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Publication number: 20130106327Abstract: A motor drive controller to drive a motor, based on multiple sensors that generates multiple sensor signals corresponding to different positions of the rotor; including a first phase detector to compare a respective one of the multiple sensor signals with a paired sensor signal from the same sensor to detect phases of the rotor, and output a first phase information signal representing a first detected phase; a phase divider to divide the phases, detected by the first phase detector into multiple predetermined phase intervals; a signal selector to select one of the respective multiple sensor signals from the multiple sensors in the multiple predetermined phase interval; and a second phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a second phase information signal representing a second detected phase.Type: ApplicationFiled: October 23, 2012Publication date: May 2, 2013Applicant: RICOH COMPANY, LTD.Inventors: Tomohiko Kamatani, Haruyuki Suzuki, Fumihiro Shimizu, Katsuhisa Furuse
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Publication number: 20130106326Abstract: A motor drive controller to control a motor via multiple sensors includes a first phase detector to compare respective differential pairs of the sensor signals from the same sensor to detect phases of the rotor, and output a first phase information signal; a second phase detector to compare a respective one of the multiple sensor signals with another sensor signal from the different sensor to detect the phases and output a second phase information signal; a phase divider to divide the phases, detected by the first and second phase detectors, into multiple predetermined phase intervals; a signal selector to select one of the multiple sensor signals in the multiple predetermined phase intervals; and a third phase detector to detect whether the signal selected by the signal selector reaches a predetermined threshold level corresponding to a predetermined phase of the rotor, and output a third phase information signal.Type: ApplicationFiled: October 23, 2012Publication date: May 2, 2013Applicant: RICOH COMPANY, LTD.Inventors: Tomohiko Kamatani, Haruyuki Suzuki, Fumihiro Shimizu, Katsuhisa Furuse
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Publication number: 20130099708Abstract: Disclosed is an angle detection device including plural sensors that output corresponding sinusoidal signals, wherein each of the sinusoidal signals varies sinusoidally depending on a rotational angle of a rotor of a motor, and each of the sinusoidal signals has a phase that depends on a position of the corresponding sensor; a vector generating unit that generates a vector represented by a result of mutually operating at least two of the sinusoidal signals; a vector rotation unit that rotates the vector by operating the vector and reference sine waves having corresponding phases; and an angle search unit that causes the vector rotation unit to sequentially rotate the vector until a phase of the vector becomes a predetermined phase, and that detects an angle between the vector prior to being rotated and the predetermined phase as the rotational angle of the rotor of the motor.Type: ApplicationFiled: October 11, 2012Publication date: April 25, 2013Inventors: Fumihiro SHIMIZU, Haruyuki Suzuki, Tomohiko Kamatani, Katsuhisa Furuse
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Patent number: 8405329Abstract: A motor drive controller includes a position detector that detects and outputs positional signals representing rotational positions of the magnetic rotor at first resolution, a position change detector that detects and outputs position change signals representing rotational positions of the magnetic rotor at second resolution higher than the first resolution, a phase synchronizing circuit that generates and outputs low resolution absolute phase information based on the positional and position change signals. The phase synchronizing circuit generates and outputs high-resolution absolute phase information based on the position change signals. A drive voltage signal outputting device outputs a drive voltage signal causing the current to flow through the coils in accordance with the absolute phase information.Type: GrantFiled: October 18, 2010Date of Patent: March 26, 2013Assignee: Ricoh Company, Ltd.Inventor: Fumihiro Shimizu
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Patent number: 8288978Abstract: A motor driver, including a bridge circuit including a switching element and a diode, connecting with a coil terminal of each phase of a polyphase motor; a modulator modulating a voltage value applied to the coil terminal of each phase such that a minimum voltage value applied thereto is zero; a PWM signal generator generating a PWM signal, based on the voltage value applied to each phase, which is modulated by the modulator; and a switching element drive signal generator generating a switching element drive signal to drive the switching signal, based on the PWM signal generated by the PWM signal generator.Type: GrantFiled: November 2, 2009Date of Patent: October 16, 2012Assignee: Ricoh Company, Ltd.Inventor: Fumihiro Shimizu
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Patent number: 8258731Abstract: A motor starting apparatus includes a driving signal generating unit that generates an open-loop driving signal and a drive circuit that is connected to a motor. The driving signal generating unit includes a data storing unit that stores therein predetermined data, a velocity integrating unit that integrates velocity data, a phase adjusting signal generating unit that generates a phase adjusting signal, a three-phase driving signal generating unit that generates a three-phase applied voltage, and a drive circuit driving unit that generates a driving signal of the motor. The three-phase driving signal generating unit performs open-loop driving by outputting the three-phase applied voltage based on the phase adjusting signal to the drive circuit driving unit.Type: GrantFiled: July 4, 2008Date of Patent: September 4, 2012Assignee: Ricoh Company, LimitedInventor: Fumihiro Shimizu
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Publication number: 20110089874Abstract: A motor drive controller includes a position detector that detects and outputs positional signals representing rotational positions of the magnetic rotor at first resolution, a position change detector that detects and outputs position change signals representing rotational positions of the magnetic rotor at second resolution higher than the first resolution, a phase synchronizing circuit that generates and outputs low resolution absolute phase information based on the positional and position change signals. The phase synchronizing circuit generates and outputs high-resolution absolute phase information based on the position change signals. A drive voltage signal outputting device outputs a drive voltage signal causing the current to flow through the coils in accordance with the absolute phase information.Type: ApplicationFiled: October 18, 2010Publication date: April 21, 2011Applicant: Ricoh Company, Ltd.Inventor: Fumihiro Shimizu
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Publication number: 20100188031Abstract: A motor starting apparatus includes a driving signal generating unit that generates an open-loop driving signal and a drive circuit that is connected to a motor. The driving signal generating unit includes a data storing unit that stores therein predetermined data, a velocity integrating unit that integrates velocity data, a phase adjusting signal generating unit that generates a phase adjusting signal, a three-phase driving signal generating unit that generates a three-phase applied voltage, and a drive circuit driving unit that generates a driving signal of the motor. The three-phase driving signal generating unit performs open-loop driving by outputting the three-phase applied voltage based on the phase adjusting signal to the drive circuit driving unit.Type: ApplicationFiled: July 4, 2008Publication date: July 29, 2010Inventor: Fumihiro Shimizu
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Publication number: 20100117576Abstract: A motor driver, including a bridge circuit including a switching element and a diode, connecting with a coil terminal of each phase of a polyphase motor; a modulator modulating a voltage value applied to the coil terminal of each phase such that a minimum voltage value applied thereto is zero; a PWM signal generator generating a PWM signal, based on the voltage value applied to each phase, which is modulated by the modulator; and a switching element drive signal generator generating a switching element drive signal to drive the switching signal, based on the PWM signal generated by the PWM signal generator.Type: ApplicationFiled: November 2, 2009Publication date: May 13, 2010Inventor: Fumihiro Shimizu
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Patent number: 7296277Abstract: A disk rotation device rotationally driving a disk includes a housing body, a conveyance body installed in the housing body so as to be capable to move between a first position positioned inside of the housing, the first position being where the disk is rotation driven, and a second position positioned outside of the housing body, the second position being where the disk is put on or taken off, a rotation mechanism provided in the conveyance body and having a rotational part which is rotationally driven by a motor and at which rotational part the disk is set, and a braking device which brakes by applying a friction force to the rotational part in a case where the conveyance body is situated at a side of the second position closer than a designated standard position between the first position and the second position, and which turns off application of the friction force in a case where the conveyance body is situated at a side of the first position closer than the standard position.Type: GrantFiled: December 16, 2004Date of Patent: November 13, 2007Assignee: Ricoh Company, Ltd.Inventors: Takehide Ohno, Fumihiro Shimizu
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Publication number: 20060010457Abstract: A disk rotation device rotationally driving a disk includes a housing body, a conveyance body installed in the housing body so as to be capable to move between a first position positioned inside of the housing, the first position being where the disk is rotation driven, and a second position positioned outside of the housing body, the second position being where the disk is put on or taken off, a rotation mechanism provided in the conveyance body and having a rotational part which is rotationally driven by a motor and at which rotational part the disk is set, and a braking device which brakes by applying a friction force to the rotational part in a case where the conveyance body is situated at a side of the second position closer than a designated standard position between the first position and the second position, and which turns off application of the friction force in a case where the conveyance body is situated at a side of the first position closer than the standard position.Type: ApplicationFiled: December 16, 2004Publication date: January 12, 2006Inventors: Takehide Ohno, Fumihiro Shimizu
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Patent number: 6573625Abstract: In a motor device for vehicles, a brush holder is interposed between a motor yoke housing and a reduction gear unit housing has a holder body and a connector unit integrally formed with each other. The connector unit holds therein connector terminals having base ends connected to brushes. A sealing cover is molded integrally on the holder body and the base ends of the connector terminals. The sealing cover seals insides of the yoke housing and the gear housing water-tightly from the outside. The sealing cover is preferably made of rubber, elastomer or adhesive resin, and formed with the brush holder by two-color molding. The sealing cover has a cylindrical cover part extending from the connector unit, and the motor device is mounted in a vehicle door with the cylindrical cover part being attached to the vehicle door for electrical connection with an external power source.Type: GrantFiled: March 28, 2001Date of Patent: June 3, 2003Assignee: Asmo Co., Ltd.Inventors: Fumihiro Shimizu, Hiroaki Yamamoto, Katsuhiko Torii, Kenji Kashima, Kengo Yamamura
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Publication number: 20010026104Abstract: In a motor device for vehicles, a brush holder is interposed between a motor yoke housing and a reduction gear unit housing has a holder body and a connector unit integrally formed with each other. The connector unit holds therein connector terminals having base ends connected to brushes. A sealing cover is molded integrally on the holder body and the base ends of the connector terminals. The sealing cover seals insides of the yoke housing and the gear housing water-tightly from the outside. The sealing cover is preferably made of rubber, elastomer or adhesive resin, and formed with the brush holder by two-color molding. The sealing cover has a cylindrical cover part extending from the connector unit, and the motor device is mounted in a vehicle door with the cylindrical cover part being attached to the vehicle door for electrical connection with an external power source.Type: ApplicationFiled: March 28, 2001Publication date: October 4, 2001Inventors: Fumihiro Shimizu, Hiroaki Yamamoto, Katsuhiko Torii, Kenji Kashima, Kengo Yamamura
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Patent number: 5438801Abstract: A quarter window opening/closing apparatus in which a torsion coil spring is provided at a link-connecting portion where a second link is rotatably connected to a first link is provided. When the quarter window is in a state other than a fully closed or fully open state, the torsion coil spring urges the quarter window in its opening direction by means of the second link. Accordingly, the occurrence of rattling of the quarter window is prevented even when the quarter window is in a state other than fully closed or fully open.Type: GrantFiled: June 10, 1994Date of Patent: August 8, 1995Assignee: Asmo Co., Ltd.Inventors: Mikiya Ishihara, Takahiro Yamada, Fumihiro Shimizu