Patents by Inventor Iwao Nakanishi

Iwao Nakanishi 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: 20230318443
    Abstract: A power supply apparatus (100) according to the present disclosure converts an input voltage supplied from a power source to a predetermined direct current voltage. The power supply apparatus (100) includes an inrush current prevention circuit (120) based on a buck converter system and configured to suppress a flow of inrush current from the power source to the power supply apparatus (100) and a boost converter circuit (130) configured to output the predetermined direct current voltage. A choke coil (104) included in the inrush current prevention circuit (120) and a choke coil (104) included in the boost converter circuit (130) are a common choke coil. A smoothing capacitor (107) included in the inrush current prevention circuit (120) and a smoothing capacitor (107) included in the boost converter circuit (130) are a common smoothing capacitor.
    Type: Application
    Filed: February 13, 2023
    Publication date: October 5, 2023
    Inventors: Naoya Aso, Kei Fukuhara, Masahiko Suzuki, Iwao Nakanishi
  • Patent number: 11569735
    Abstract: A power supply system includes at least two power supply devices that supply a current to a load. Each of the at least two power supply devices includes a converter configured to generate a current that is to be supplied to the load, an FET that is connected in series between the converter and the load, a gate voltage monitoring circuit configured to monitor whether a gate voltage of the FET has fallen below a predetermined first reference voltage, and an alarm generation circuit configured to generate an alarm according to a result of monitoring by the gate voltage monitoring circuit.
    Type: Grant
    Filed: March 22, 2022
    Date of Patent: January 31, 2023
    Assignee: YOKOGAWA ELECTRIC CORPORATION
    Inventors: Yuusuke Shimizu, Kei Fukuhara, Iwao Nakanishi
  • Publication number: 20220320996
    Abstract: A power supply system includes at least two power supply devices that supply a current to a load. Each of the at least two power supply devices includes a converter configured to generate a current that is to be supplied to the load, an FET that is connected in series between the converter and the load, a gate voltage monitoring circuit configured to monitor whether a gate voltage of the FET has fallen below a predetermined first reference voltage, and an alarm generation circuit configured to generate an alarm according to a result of monitoring by the gate voltage monitoring circuit.
    Type: Application
    Filed: March 22, 2022
    Publication date: October 6, 2022
    Applicant: Yokogawa Electric Corporation
    Inventors: Yuusuke Shimizu, Kei Fukuhara, Iwao Nakanishi
  • Patent number: 10992131
    Abstract: A power supply system includes at least two power supply apparatuses that supply current to one load. Each power supply apparatus includes a converter that supplies current to the load, a FET connected in series between the converter and the load, a current detection unit that detects current flowing between the converter and the load, and a droop characteristic controller that causes output voltage of the converter to droop at a droop rate determined based on the magnitude of load current flowing from the converter towards the load. The droop rate is greater when the load current is included in a first current section than when the load current is included in each of a second current section and a third current section. The second current section includes smaller current than the first current section. The third current section includes larger current than the first current section.
    Type: Grant
    Filed: March 10, 2020
    Date of Patent: April 27, 2021
    Assignee: Yokogawa Electric Corporation
    Inventors: Kei Fukuhara, Iwao Nakanishi
  • Publication number: 20200303922
    Abstract: A power supply system includes at least two power supply apparatuses that supply current to one load. Each power supply apparatus includes a converter that supplies current to the load, a FET connected in series between the converter and the load, a current detection unit that detects current flowing between the converter and the load, and a droop characteristic controller that causes output voltage of the converter to droop at a droop rate determined based on the magnitude of load current flowing from the converter towards the load. The droop rate is greater when the load current is included in a first current section than when the load current is included in each of a second current section and a third current section. The second current section includes smaller current than the first current section. The third current section includes larger current than the first current section.
    Type: Application
    Filed: March 10, 2020
    Publication date: September 24, 2020
    Applicant: Yokogawa Electric Corporation
    Inventors: Kei FUKUHARA, Iwao NAKANISHI
  • Patent number: 6088244
    Abstract: A switching power supply comprising a main converter that turns ON and OFF a DC current applied to a primary winding of a main transformer by a main switching element and outputs a main output voltage to a secondary circuit by rectifying and smoothing current induced in a secondary winding; an error amplifier generating an error voltage between the main output voltage and a first reference voltage; an over-voltage protection circuit that generates an over-voltage protection signal when the main output voltage exceeds a second reference voltage; a PWM circuit to control a drive signal for the main switching element to minimize error voltage outputted by the error amplifier; and a shut-down execution circuit that stops the main converter operation when the over-voltage protection signal is generated; wherein are provided a device to superimpose the over-voltage protection signal on the error signal of the main output voltage induced in the secondary winding and to transmit the superimposed signal to the primary
    Type: Grant
    Filed: November 10, 1999
    Date of Patent: July 11, 2000
    Assignee: Yokogawa Electric Corp.
    Inventors: Masaki Shioya, Hideaki Matsumura, Takumi Oe, Iwao Nakanishi
  • Patent number: 6023178
    Abstract: A pulse width control IC circuit that greatly reduces price, increases packaging density,and improves reliability for switching power supply units, wherein the IC circuit is on a single chip and includes a main converter control section that controls the ON and OFF actions of a main switch outside the IC, an output MOSFET, and an auxiliary converter control section that controls the ON and OFF actions of the output MOSFET.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: February 8, 2000
    Assignee: Yokogawa Electric Corporation
    Inventors: Masaki Shioya, Hideaki Matsumura, Takumi Ooe, Iwao Nakanishi, Masuo Hanawaka