Patents by Inventor Masahiro Matsuo

Masahiro Matsuo 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).

  • Publication number: 20080211474
    Abstract: A step-up/down DC-DC converter is disclosed that includes: a step-up/down part generating an output voltage by stepping up or down an input voltage; and a control part generating an error signal indicating an error between a voltage value obtained by dividing the output voltage and a predetermined reference voltage, and causing the step-up/down part to perform a step-up or step-down operation based on the comparison between the error signal and first and second triangle wave signals. The control part includes a first circuit generating the first triangle wave signal for step-down control and a second circuit generating the second triangle wave signal for step-up control. The first circuit generates a clock signal synchronized with the first triangle wave signal, and outputs the clock signal to the second circuit. The second circuit generates the second triangle wave signal synchronized with the first triangle wave signal based on the input clock signal.
    Type: Application
    Filed: January 25, 2008
    Publication date: September 4, 2008
    Inventors: Shohichi Nitta, Masahiro Matsuo, Ritsuko Nomura
  • Publication number: 20080209457
    Abstract: The invention provides a disc device capable of offering good SATA interface performance by optimizing the placement of the SATA connector relative to the control board, solving problems concerning noise or unnecessary radiation. A driver IC and DSP for executing main processing concerning disc recording or reproduction processing are installed in a main printed circuit board. A SATA connector having a power supply terminal and signal terminal is fixed to the main printed circuit board. The SATA connector is placed on the board opposite the DSP. Patterns each connecting the power supply terminal to the driver IC and connecting the signal terminal and DSP are formed on the board. The SATA connector and DSP are placed on the driver IC side relative to the central line of the board, the power supply terminal is placed on the driver IC side, and the signal terminal is placed on the DSP side.
    Type: Application
    Filed: September 21, 2007
    Publication date: August 28, 2008
    Inventors: Yoichi Narui, Goshi Shiroishi, Ikuo Nishida, Kenji Watabe, Masahiro Matsuo
  • Publication number: 20080205209
    Abstract: The invention provides an optical disc device conducting highly accurate skew adjustment, avoiding an increase in the number of components, and achieving downsizing. This optical disc device includes: a guide shaft for supporting an optical pickup and guiding its movement; a chassis the guide shaft is attached to; a coil spring attached to the chassis for applying force to an end of the guide shaft; an adjustment screw for adjusting the force applied by the coil spring, provided opposite the coil spring with respect to the guide shaft; and a weight addition member attached to the chassis, wherein internal threads for engaging with the adjustment screw are formed in the weight addition member, and the axis of the adjustment screw engaged with the internal thread, the center of a cross section of the guide shaft perpendicular to its axis, and the axis of the coil spring are aligned along the same line.
    Type: Application
    Filed: September 21, 2007
    Publication date: August 28, 2008
    Inventors: KENJI WATABE, Ikuo Nishida, Yoichi Narui, Masahiro Matsuo
  • Publication number: 20080184279
    Abstract: An optical disc apparatus, comprising a tray 2, attached to be insertable within housings 9 and 10, and within the housings are included a disc motor 3, an optical pickup 4 and a moving mechanism thereof, and also a unit mechanism chassis 5 for moving the optical pickup thereon and a controller substrate 71 disposed below the unit mechanism chassis for controlling the optical pickup, and further, a wide-width flexible cable 8 for electrical connection between the controller substrate and the optical pickup, wherein the optical pickup mounts laser units 41, 42 and 43 including three (3) pieces of elements, each emitting a laser light different in the wavelength thereof, a penetrating portion 2b and a wall portion 2e are provided in a part of left bottom surface of the tray, while forming a cutoff portion 55 in a part of the chassis, thereby guiding the airflow generated accompanying with rotation of the optical disc onto the optical pickup, with certainty.
    Type: Application
    Filed: September 28, 2007
    Publication date: July 31, 2008
    Inventors: Kenji Watabe, Ikuo Nishida, Yoichi Narui, Masahiro Matsuo, Takayuki Fujimoto
  • Patent number: 7391189
    Abstract: A step-up/down DC-DC converter is disclosed that includes: a step-up/down part generating an output voltage by stepping up or down an input voltage; and a control part generating an error signal indicating an error between a voltage value obtained by dividing the output voltage and a predetermined reference voltage, and causing the step-up/down part to perform a step-up or step-down operation based on the comparison between the error signal and first and second triangle wave signals. The control part includes a first circuit generating the first triangle wave signal for step-down control and a second circuit generating the second triangle wave signal for step-up control. The first circuit generates a clock signal synchronized with the first triangle wave signal, and outputs the clock signal to the second circuit. The second circuit generates the second triangle wave signal synchronized with the first triangle wave signal based on the input clock signal.
    Type: Grant
    Filed: April 22, 2004
    Date of Patent: June 24, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Shohichi Nitta, Masahiro Matsuo, Ritsuko Nomura
  • Publication number: 20080122419
    Abstract: A step-down switching regulator is disclosed that includes a first switching element, a smoothing circuit part including an inductor and a second switching element for synchronous rectification, a switching controller circuit part, and a reverse current detector circuit part that detects a reverse current flowing from the inductor to the second switching element and interrupts the reverse current by causing the switching controller circuit part to turn off the second switching element upon detection of the reverse current. Detecting a change in a set voltage, the reverse current detector circuit part stops, for a predetermined period of time, the operation of causing the switching controller circuit part to turn off the second switching element due to detection of the reverse current, and after the predetermined period of time is over, causes the switching controller circuit part to turn off the second switching element upon detection of the reverse current.
    Type: Application
    Filed: January 29, 2008
    Publication date: May 29, 2008
    Applicant: Ricoh Company, Ltd.
    Inventors: Shinya Shimizu, Masahiro Matsuo
  • Patent number: 7352160
    Abstract: A step-down switching regulator is disclosed that includes a first switching element, a smoothing circuit part including an inductor and a second switching element for synchronous rectification, a switching controller circuit part, and a reverse current detector circuit part that detects a reverse current flowing from the inductor to the second switching element and interrupts the reverse current by causing the switching controller circuit part to turn off the second switching element upon detection of the reverse current. Detecting a change in a set voltage, the reverse current detector circuit part stops, for a predetermined period of time, the operation of causing the switching controller circuit part to turn off the second switching element due to detection of the reverse current, and after the predetermined period of time is over, causes the switching controller circuit part to turn off the second switching element upon detection of the reverse current.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: April 1, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinya Shimizu, Masahiro Matsuo
  • Patent number: 7349624
    Abstract: A digital broadcast signal of a channel received in a tuner is converted into digital data by a digital demodulation section. Based on the digital data, a CPU detects the partial of the corresponding subchannel from the whole transport stream (TS) of the digital data and causes a system controller to extract digital data of the subchannel and record the digital data on a hard disk in a predetermined format.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: March 25, 2008
    Assignee: Funai Electric Co., Ltd.
    Inventor: Masahiro Matsuo
  • Publication number: 20080007232
    Abstract: A DC-DC converting apparatus including a step-up and step-down circuit stepping up/down an input voltage to generate an output voltage and a PWM control circuit. The PWM control circuit generates an error signal, first to third voltages, a first triangular wave signal varying between the first and second voltages, and a second triangular wave signal varying between the third voltage and a fourth voltage determined based on the first to third voltages. The PWM control circuit compares the error signal with the first and second triangular wave signals and causes the step-up and step-down circuit to step up/down the input voltage based on the comparison. The first to fourth voltages V1 to V4 satisfy V1<V4<V2<V3 and V4=V3?(V2?V1). At least one of the first to third voltages is variably set to make a time in which voltage ranges of the first and second triangular wave signals overlap longer than a delay time caused by the comparison.
    Type: Application
    Filed: March 21, 2007
    Publication date: January 10, 2008
    Inventors: Shoichi Nitta, Masahiro Matsuo
  • Publication number: 20070283370
    Abstract: A flexible printed-wiring circuit board that connects a signal-processing circuit board and a pickup is prevented from coming into contact with the bottom (or the like) of a tray and thus becoming damaged. The flexible printed-wiring circuit board (FPC board) is disposed in a U-shaped folded state in a space sandwiched between a surface along which the tray moves, and a surface on which the signal-processing circuit board is mounted. An extension portion that restricts deformation of the FPC board toward the tray is provided at a connecting end of the pickup. Length D of the extension portion is set such that length S of the FPC board from a front end of the extension portion to a fold-back position of the FPC board is equal to or less than a required value.
    Type: Application
    Filed: October 3, 2006
    Publication date: December 6, 2007
    Inventors: Masahiro Matsuo, Yoichi Narui, Ikuo Nishida
  • Publication number: 20070216387
    Abstract: A switching regulator including two switching elements and a control switching part. The two switching elements perform a switching operation according to a control signal to control an output voltage. One of the two switching elements is larger in ON-resistance and smaller in control electrode capacitance than the other. The control switching part performs PFM control over the one of the two switching elements to output a first predetermined voltage in a first operation mode, performs PWM control over the two switching elements to output a second predetermined voltage higher than the first predetermined voltage in a second operation mode, and switches the first operation mode to the second operation mode by performing the PFM control, changing the first predetermined voltage to the second predetermined voltage, and switching the PFM control to the PWM control after a first predetermined time elapses since start of increase in the output voltage.
    Type: Application
    Filed: April 16, 2007
    Publication date: September 20, 2007
    Inventors: Masahiro Matsuo, Tomonari Katoh
  • Patent number: 7262588
    Abstract: A switching regulator includes a first switching element to perform a switching operation in accordance with a first control signal input thereto to control an output voltage based on an input voltage, a second switching element having a size smaller than the first switching element to perform a switching operation in accordance with one of the first control signal and a second control signal input thereto to control an output voltage based on the input voltage, and a control circuit to control the first and second switching elements to perform the switching operations in one of a normal operation mode and a light load operation mode in which a current consumed by a load connected to the switching regulator is smaller than a current consumed in the normal operation mode, and control the first switching element to be turned off in the light load operation mode.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: August 28, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahiro Matsuo, Tomonari Katoh
  • Patent number: 7260316
    Abstract: A transport stream TSd generated from a digital broadcast signal and a transport stream TSa generated from an analog broadcast signal are recorded simultaneously and a portion of TSd wherein the reception state of the digital broadcast is bad is replaced with TSa corresponding to the defective portion for compensation. A composite TS consisting of good TSd and TSa corresponding to defective TSd 102 is formed and recorded.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: August 21, 2007
    Assignee: Funai Electric Co., Ltd.
    Inventor: Masahiro Matsuo
  • Publication number: 20070159151
    Abstract: A switching regulator converts an input voltage to a predetermined voltage and outputs the predetermined voltage to a load through an output terminal. The switching regulator includes a first switching element, a second switching element, a control switching circuit part, and a smoothing circuit. When a first operating mode in which a PFM control is performed and a voltage from the output terminal becomes a first voltage is shifted to a second operating mode in which a PWM control is performed and the voltage from the output terminal becomes a second voltage larger than the first voltage, the control switching circuit part increases the voltage from the output terminal stepwise progressively from the first voltage to the second voltage while performing the PWM control.
    Type: Application
    Filed: November 24, 2005
    Publication date: July 12, 2007
    Inventors: Tomonari Katoh, Masahiro Matsuo
  • Publication number: 20070150909
    Abstract: In a disc drive for achieving cooling of an electronic part therein, as well as, suppressing transmission of noises generated from a disc clamper, etc., a channel member 18 for introducing an outside air into an inside is disposed between a supporting member 15 and a top-cover 10, within an inside thereof is formed a vortex-like channel, extending from a center to an outer periphery thereof. At the center of the channel member 18 is formed an opening 19 for introducing the outside air into the inside of the disc drive, and on the top-cover 10 are provided plural numbers of openings 20 for taking the outside air into the channel member 18. When an optical disc 6 rotates, pressure generated on an upper surface thereof comes to be negative to the outside air, then the outside air is taken from the openings 20, through the vortex-like channel of the channel member 18 and the opening 19, into the inside of the drive, so as to pass through electronic parts, such as, an optical pickup, etc., thereby cooling them.
    Type: Application
    Filed: September 28, 2006
    Publication date: June 28, 2007
    Inventors: Takayuki Fujimoto, Ikuo Nishida, Kohei Takita, Yoichi Narui, Masahiro Matsuo
  • Patent number: 7221129
    Abstract: A switching regulator including two switching elements and a control switching part. The two switching elements perform a switching operation according to a control signal to control an output voltage. One of the two switching elements is larger in ON-resistance and smaller in control electrode capacitance than the other. The control switching part performs PFM control over the one of the two switching elements to output a first predetermined voltage in a first operation mode, performs PWM control over the two switching elements to output a second predetermined voltage higher than the first predetermined voltage in a second operation mode, and switches the first operation mode to the second operation mode by performing the PFM control, changing the first predetermined voltage to the second predetermined voltage, and switching the PFM control to the PWM control after a first predetermined time elapses since start of increase in the output voltage.
    Type: Grant
    Filed: April 27, 2005
    Date of Patent: May 22, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahiro Matsuo, Tomonari Katoh
  • Patent number: 7220133
    Abstract: An optical disc apparatus is constructed so that: a first member formed of a plate-shaped or sheet-shaped insulating material is disposed on a flexible printed-wiring board which interconnects a main circuit board and an optical pickup; a second member with a protruding portion is disposed at both sides of the wiring section of the flexible printed-wiring board, on the first member; the protrusions are coupled with a main circuit board by, for example, being inserted into the holes of a planar region on the main circuit board; and the second member presses the flexible printed-wiring board against the main circuit board from one side of the wiring board via the first member, thus fixing the wiring board.
    Type: Grant
    Filed: March 7, 2006
    Date of Patent: May 22, 2007
    Assignee: Hitachi-LG Data Storage, Inc.
    Inventors: Masahiro Matsuo, Yoichi Narui, Kohei Takita
  • Patent number: 7202644
    Abstract: A DC-DC converting apparatus including a step-up and step-down circuit stepping up/down an input voltage to generate an output voltage and a PWM control circuit. The PWM control circuit generates an error signal, first to third voltages, a first triangular wave signal varying between the first and second voltages, and a second triangular wave signal varying between the third voltage and a fourth voltage determined based on the first to third voltages. The PWM control circuit compares the error signal with the first and second triangular wave signals and causes the step-up and step-down circuit to step up/down the input voltage based on the comparison. The first to fourth voltages V1 to V4 satisfy V1<V4<V2<V3 and V4=V3?(V2?V1). At least one of the first to third voltages is variably set to make a time in which voltage ranges of the first and second triangular wave signals overlap longer than a delay time caused by the comparison.
    Type: Grant
    Filed: June 16, 2005
    Date of Patent: April 10, 2007
    Assignee: Ricoh Company, Ltd
    Inventors: Shoichi Nitta, Masahiro Matsuo
  • Publication number: 20070075697
    Abstract: A step-down switching regulator is disclosed that includes a first switching element, a smoothing circuit part including an inductor and a second switching element for synchronous rectification, a switching controller circuit part, and a reverse current detector circuit part that detects a reverse current flowing from the inductor to the second switching element and interrupts the reverse current by causing the switching controller circuit part to turn off the second switching element upon detection of the reverse current. Detecting a change in a set voltage, the reverse current detector circuit part stops, for a predetermined period of time, the operation of causing the switching controller circuit part to turn off the second switching element due to detection of the reverse current, and after the predetermined period of time is over, causes the switching controller circuit part to turn off the second switching element upon detection of the reverse current.
    Type: Application
    Filed: December 5, 2006
    Publication date: April 5, 2007
    Inventors: Shinya Shimizu, Masahiro Matsuo
  • Publication number: 20070079312
    Abstract: An optical disc drive, comprising: a housing; a tray for transferring an optical disc, having a disc mounting portion for mounting the optical disc thereon, and being movable into an inside and a front of the housing; a motor for rotationally driving said optical disc; an optical pickup, having one or more of laser diode(s) for generating a laser beam for conducting recording/reproducing of information onto/from the optical disc, and for irradiating the laser beam upon the optical disc; and a first penetrating hole, for letting the rotation device and the laser beam passing therethrough, being provided within the disc mounting portion and also in rear of said disc mounting portion, on the tray, wherein a second penetrating hole is further provided in rear of the disc mounting portion, in an upstream side of rotating direction of the optical disc than the first penetrating portion, and the second penetrating portion is larger in area than a total of area(s) obtained by projecting the laser diode(s) onto the op
    Type: Application
    Filed: September 29, 2006
    Publication date: April 5, 2007
    Inventors: Nobuyuki Isoshima, Yukinobu Abe, Takayuki Fujimoto, Ikuo Nishida, Masahiro Matsuo