Patents by Inventor Takuya Domoto

Takuya Domoto 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).

  • Patent number: 10050550
    Abstract: Downsizing a Cockcroft-Walton high-voltage generation device may cause discharge from the connections of respective components to potentially lack insulation reliability. A Cockcroft-Walton circuit (1) is configured to include capacitors (2a-1 to 2a-4) connected in series and capacitors (2b-1 to 2b-4) connected in series, each having end electrodes (22) at both ends, respectively. One capacitor (2a-1) is electrically connected with the other capacitor (2a-2), which is adjacent in series to the former at a connection (7a-1). The connection (7a-1) is arranged so as not to protrude outside a first space (9) between the end electrode (22) of the one capacitor (2a-1) and the end electrode (22) of the other capacitor (2a-2). Further, the anode of a diode (3a-1) and the cathode of a diode (3b-1) are electrically connected to the connection (7a-1).
    Type: Grant
    Filed: July 9, 2014
    Date of Patent: August 14, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Morita, Toranosuke Takeuchi, Tomoharu Ino, Takuya Domoto
  • Publication number: 20160156280
    Abstract: Downsizing a Cockcroft-Walton high-voltage generation device may cause discharge from the connections of respective components to potentially lack insulation reliability. A Cockcroft-Walton circuit (1) is configured to include capacitors (2a-1 to 2a-4) connected in series and capacitors (2b-1 to 2b-4) connected in series, each having end electrodes (22) at both ends, respectively. One capacitor (2a-1) is electrically connected with the other capacitor (2a-2), which is adjacent in series to the former at a connection (7a-1). The connection (7a-1) is arranged so as not to protrude outside a first space (9) between the end electrode (22) of the one capacitor (2a-1) and the end electrode (22) of the other capacitor (2a-2). Further, the anode of a diode (3a-1) and the cathode of a diode (3b-1) are electrically connected to the connection (7a-1).
    Type: Application
    Filed: July 9, 2014
    Publication date: June 2, 2016
    Inventors: Hiroshi MORITA, Toranosuke TAKEUCHI, Tomoharu INO, Takuya DOMOTO
  • Patent number: 9036784
    Abstract: A power converter is configured to include an inverter which converts a DC output into an AC voltage of a predetermined frequency, and a high voltage generator which receives an output from output terminals of the inverter and boosts the output to a desired high DC voltage. The high voltage generator includes a transformer, and the primary windings of the transformer are connected to the output terminals of the inverter in parallel by conductive wires connected to both ends of each primary winding. Further, a current sensor is provided to detect a current flowing through each of the primary windings, and a control unit determines abnormalities of a path of the inverter and the primary windings on the basis of a value of the current sensor.
    Type: Grant
    Filed: February 8, 2011
    Date of Patent: May 19, 2015
    Assignee: HITACHI MEDICAL CORPORATION
    Inventors: Takatsugu Oketa, Hirokazu Iijima, Takuya Domoto
  • Publication number: 20120294428
    Abstract: In order to prevent breakage of a power converter, a current which flows into an inverter (3) in the power converter is detected. The inverter (3) is equipped with two or more primary windings in parallel with each other. The current flowing through each of the primary windings is detected by current sensors (17, 6). A control unit (22) determines from the outputs of the current sensors that an abnormality occurs, when current does not flow through any of the primary windings.
    Type: Application
    Filed: February 8, 2011
    Publication date: November 22, 2012
    Applicant: HITACHI MEDICAL CORPORATION
    Inventors: Takatsugu Oketa, Hirokazu Iijima, Takuya Domoto
  • Patent number: 8249217
    Abstract: There is provided an inverter device that can detect short-circuit of a switching element of an inverter circuit even under a load condition that a PWM driving signal is very small. The inverter device is provided with means for independently supplying a short-circuit detecting PWM driving signal to respective switching elements S1 to S4 at different timings before the inverter circuit 21 supplies a PWM driving signal for supplying power to a high voltage generating device 31, successively turning on the respective switching elements S1 to S4 with the short-circuit detecting PWM driving signal, detecting on-voltages of the switching elements S1 to S4 which are connected to the turned-on switching elements S1 to S4 in series, and detecting overcurrent or short-circuit states of the switching elements S1 to S4.
    Type: Grant
    Filed: December 1, 2008
    Date of Patent: August 21, 2012
    Assignee: Hitachi Medical Corporation
    Inventors: Hirokazu Iijima, Takuya Domoto, Takayuki Masaki
  • Patent number: 7928600
    Abstract: A DC high voltage power source is constituted by an AC-DC converting means (4, 6) that converts a voltage of a commercial AC power source (3) to a DC voltage and steps up the converted DC voltage, a DC-AC converting means (7) that converts the DC voltage stepped up by the previous means to an AC voltage, two insulating transformer (8, 9) that steps up the AC voltage converted by the previous converting means while insulating each others and a series connection of DC voltages obtained after converting the output voltages from the transformers to DCs and smoothing the same.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: April 19, 2011
    Assignee: Hitachi Medical Corporation
    Inventors: Shingo Hishikawa, Takuya Domoto
  • Publication number: 20100254515
    Abstract: There is provided an inverter device that can detect short-circuit of a switching element of an inverter circuit even under a load condition that a PWM driving signal is very small. The inverter device is provided with means for independently supplying a short-circuit detecting PWM driving signal to respective switching elements S1 to S4 at different timings before the inverter circuit 21 supplies a PWM driving signal for supplying power to a high voltage generating device 31, successively turning on the respective switching elements S1 to S4 with the short-circuit detecting PWM driving signal, detecting on-voltages of the switching elements S1 to S4 which are connected to the turned-on switching elements S1 to S4 in series, and detecting overcurrent or short-circuit states of the switching elements S1 to S4.
    Type: Application
    Filed: December 1, 2008
    Publication date: October 7, 2010
    Applicant: HITACHI MEDICAL CORPORATION
    Inventors: Hirokazu Iijima, Takuya Domoto, Takayuki Masaki
  • Publication number: 20100045113
    Abstract: A DC high voltage power source is constituted by an AC-DC converting means (4, 6) that converts a voltage of a commercial AC power source (3) to a DC voltage and steps up the converted DC voltage, a DC-AC converting means (7) that converts the DC voltage stepped up by the previous means to an AC voltage, two insulating transformer (8, 9) that steps up the AC voltage converted by the previous converting means while insulating each others and a series connection of DC voltages obtained after converting the output voltages from the transformers to DCs and smoothing the same.
    Type: Application
    Filed: June 30, 2006
    Publication date: February 25, 2010
    Applicant: Hitachi Medical Corporation
    Inventors: Shingo Hishikawa, Takuya Domoto
  • Patent number: 7400708
    Abstract: In an X-ray generating device of the neutral grounding system, to remove an unbalance voltage generated due to difference in impedance of parallel transformer coils of the high voltage transformer and particularly an unbalance voltage involved with difference in impedance above and below the neutral points generated in a metal X-ray tube, a plurality of currents flowing in opposite directions through primary windings of the parallel transformer coils in the high voltage transformer are passed through by or wound around a common toroidal coil or wound around an outer circumference of the toroidal coil at a predetermined ratio of winding number, and the unbalance voltage occurring to the secondary side is cancelled by changing primary current with magnetic behavior.
    Type: Grant
    Filed: September 5, 2003
    Date of Patent: July 15, 2008
    Assignee: Hitachi Medical Corporation
    Inventors: Jun Takahashi, Takuya Domoto, Hiroshi Takano
  • Patent number: 7224768
    Abstract: An X-ray tube apparatus (2) having an anode rotating mechanism for preventing damage of the anode (23) of the X-ray tube apparatus thereby to shorten the X-ray exposure waiting time. When the measured number of revolutions of a rotary anode is determined to be predetermined number from only the impedance or current information on the basis of both voltage information and current information on a stator coil (22) of motor constituent elements for rotating the rotary anode, a DC high voltage outputted from an X-ray high-voltage unit (1) is applied between the anode (23) and a cathode (24) of the X-ray tube apparatus, thus exposing a subject (130) to X-rays and imaging the subject. An X-ray generating device and a radiograph are also disclosed.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: May 29, 2007
    Assignee: Hitachi Medical Corporation
    Inventors: Takuya Domoto, Hiroshi Takano
  • Publication number: 20060165220
    Abstract: In an X-ray generating device of the neutral grounding system, to remove an unbalance voltage generated due to difference in impedance of parallel transformer coils of the high voltage transformer and particularly an unbalance voltage involved with difference in impedance above and below the neutral points generated in a metal X-ray tube, a plurality of currents flowing in opposite directions through primary windings of the parallel transformer coils in the high voltage transformer are passed through by or wound around a common toroidal coil or wound around an outer circumference of the toroidal coil at a predetermined ratio of winding number, and the unbalance voltage occurring to the secondary side is cancelled by changing primary current with magnetic behavior.
    Type: Application
    Filed: September 5, 2003
    Publication date: July 27, 2006
    Inventors: Jun Takahashi, Takuya Domoto, Hiroshi Takano
  • Publication number: 20060114623
    Abstract: A switching type power source device used for magnetic field generation coils for an MRI device in which a switching power sources (9˜11) are constituted by a first and a second multi level PWM inverter (12,13) having a same number of potential levels connected in parallel each other with respect to magnetic field generating coils (6˜8) for the MRI device working as a load as well as a switching control circuit (19) for drive controlling the first and the second multi level PWM inverter (12,13) is constituted to drive control the first and the second multi level PWM inverter (12,13) in a manner to shift the switching phases thereof each other, thereby, ripple components in currents output from the first and the second multi level PWM inverter (12,13) are canceled out each other and a current with a further reduced ripple components as a whole can be supplied to the load (6˜8).
    Type: Application
    Filed: February 6, 2004
    Publication date: June 1, 2006
    Inventors: Takuya Domoto, Hiroshi Takano
  • Publication number: 20050226384
    Abstract: An X-ray tube apparatus (2) having an anode rotating mechanism for preventing damage of the anode (23) of the X-ray tube apparatus thereby to shorten the X-ray exposure waiting time. When the measured number of revolutions of a rotary anode is determined to be predetermined number from only the impedance or current information on the basis of both voltage information and current information on a stator coil (22) of motor constituent elements for rotating the rotary anode, a DC high voltage outputted from an X-ray high-voltage unit (1) is applied between the anode (23) and a cathode (24) of the X-ray tube apparatus, thus exposing a subject (130) to X-rays and imaging the subject. An X-ray generating device and a radiograph are also disclosed.
    Type: Application
    Filed: January 24, 2003
    Publication date: October 13, 2005
    Inventors: Takuya Domoto, Hiroshi Takano
  • Patent number: 5721490
    Abstract: A power source apparatus distributes a current command value to be supplied to a load to a plurality of output current amplifiers connected in parallel with the load, and each of the output current amplifiers supplies an output current corresponding to the current command value so distributed. This power source apparatus prevents a circulating current between the output current amplifiers by controlling each output current amplifier so that the difference between the output current from each output current amplifier and the distributed current command value becomes zero, or by inserting current limiting devices into the output line of each output current amplifier.
    Type: Grant
    Filed: February 7, 1996
    Date of Patent: February 24, 1998
    Assignee: Hitachi Medical Corporation
    Inventors: Hiroshi Takano, Hiroyuki Takeuchi, Keiichi Chabata, Takuya Domoto, Takanobu Hatakeyama