Patents by Inventor Kazuhito Fujisawa

Kazuhito Fujisawa 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: 11820137
    Abstract: A liquid discharging apparatus has an integrated circuit that controls supply of a driving signal to a first driving element and to a second driving element according to a discharge control signal. The integrated circuit has: a first switch circuit that receives the driving signal and switches between output and non-output of the driving signal to the first driving element; a second switch circuit that receives the driving signal and switches between output and non-output of the driving signal to the second driving element; and a switch control circuit that receives the discharge control signal and controls whether to cause each of the first switch circuit and the second switch circuit to output the driving signal. The switch control circuit controls the first switch circuit and the second switch circuit according to the first data.
    Type: Grant
    Filed: September 29, 2021
    Date of Patent: November 21, 2023
    Inventors: Kazuhito Fujisawa, Tomoko Hara
  • Patent number: 11745504
    Abstract: A liquid discharging apparatus has a switch control circuit that controls whether to cause each of a first switch circuit, a second switch circuit, a third switch circuit, and a fourth switch circuit to output a driving signal. The switch control circuit has a fifth switch circuit, a sixth switch circuit, and a seventh switch circuit. The fifth switch circuit switches between output of the first data to the second switch circuit and output of the second data to the second switch circuit. The sixth switch circuit switches between output of the first data to the third switch circuit and output of the third data to the third switch circuit. The seventh switch circuit switches between output of the first data to the fourth switch circuit and output of the fourth data to the fourth switch circuit.
    Type: Grant
    Filed: September 28, 2021
    Date of Patent: September 5, 2023
    Inventors: Kazuhito Fujisawa, Tomoko Hara
  • Patent number: 11318736
    Abstract: A liquid ejecting apparatus includes a differential signal output circuit that outputs a pair of differential signals based on an original control signal, a pair of first signal wirings that are electrically coupled to the differential signal output circuit and propagate the differential signals, a first receiving circuit that is electrically coupled to the first signal wirings, a second receiving circuit that is electrically coupled to the first signal wirings, and an ejector that includes a drive element and that ejects a liquid from a nozzle by driving the drive element, in which the first receiving circuit outputs a control signal for controlling driving of the drive element based on the differential signals, power consumption of the first receiving circuit is larger than power consumption of the second receiving circuit, and the first receiving circuit and the second receiving circuit are electrically coupled by a second signal wiring.
    Type: Grant
    Filed: September 29, 2020
    Date of Patent: May 3, 2022
    Inventors: Kazuhito Fujisawa, Atsushi Obinata
  • Publication number: 20220097368
    Abstract: A liquid discharging apparatus has a switch control circuit that controls whether to cause each of a first switch circuit, a second switch circuit, a third switch circuit, and a fourth switch circuit to output a driving signal. The switch control circuit has a fifth switch circuit, a sixth switch circuit, and a seventh switch circuit. The fifth switch circuit switches between output of the first data to the second switch circuit and output of the second data to the second switch circuit. The sixth switch circuit switches between output of the first data to the third switch circuit and output of the third data to the third switch circuit. The seventh switch circuit switches between output of the first data to the fourth switch circuit and output of the fourth data to the fourth switch circuit.
    Type: Application
    Filed: September 28, 2021
    Publication date: March 31, 2022
    Inventors: Kazuhito FUJISAWA, Tomoko HARA
  • Publication number: 20220097362
    Abstract: A liquid discharging apparatus has an integrated circuit that controls supply of a driving signal to a first driving element and to a second driving element according to a discharge control signal. The integrated circuit has: a first switch circuit that receives the driving signal and switches between output and non-output of the driving signal to the first driving element; a second switch circuit that receives the driving signal and switches between output and non-output of the driving signal to the second driving element; and a switch control circuit that receives the discharge control signal and controls whether to cause each of the first switch circuit and the second switch circuit to output the driving signal. The switch control circuit controls the first switch circuit and the second switch circuit according to the first data.
    Type: Application
    Filed: September 29, 2021
    Publication date: March 31, 2022
    Inventors: Kazuhito FUJISAWA, Tomoko HARA
  • Publication number: 20210094285
    Abstract: A liquid ejecting apparatus includes a differential signal output circuit that outputs a pair of differential signals based on an original control signal, a pair of first signal wirings that are electrically coupled to the differential signal output circuit and propagate the differential signals, a first receiving circuit that is electrically coupled to the first signal wirings, a second receiving circuit that is electrically coupled to the first signal wirings, and an ejector that includes a drive element and that ejects a liquid from a nozzle by driving the drive element, in which the first receiving circuit outputs a control signal for controlling driving of the drive element based on the differential signals, power consumption of the first receiving circuit is larger than power consumption of the second receiving circuit, and the first receiving circuit and the second receiving circuit are electrically coupled by a second signal wiring.
    Type: Application
    Filed: September 29, 2020
    Publication date: April 1, 2021
    Inventors: Kazuhito FUJISAWA, Atsushi OBINATA
  • Publication number: 20210094283
    Abstract: A liquid ejecting apparatus includes a first differential signal output circuit that outputs a pair of first differential control signals, and a pair of first differential clock signals, a second differential signal output circuit that outputs a pair of second differential control signals, and a pair of second differential clock signals, a first differential signal receiving circuit that outputs a first control signal based on the first differential control signals and the first differential clock signals, a second differential signal receiving circuit that outputs a second control signal based on the second differential control signals and the second differential clock signals, in which transition timings of the first differential clock signals and transition timings of the second differential clock signals are different from each other.
    Type: Application
    Filed: September 28, 2020
    Publication date: April 1, 2021
    Inventors: Kazuhito FUJISAWA, Atsushi OBINATA
  • Patent number: 10239314
    Abstract: A head unit includes a discharge section, a determination circuit, and a discharge limitation circuit. The discharge section is equipped with a piezoelectric element that is configured to be displaced in accordance with changes in potential of a drive signal when the drive signal is supplied. The discharge section is configured to discharge a liquid in accordance with displacement of the piezoelectric element. The determination circuit is configured to determine whether or not the piezoelectric element has a predetermined power storage capability. The discharge limitation circuit is configured to stop supply of the drive signal to the piezoelectric element and limit discharging of liquid from the discharge section when a result of determination is negative.
    Type: Grant
    Filed: November 28, 2016
    Date of Patent: March 26, 2019
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhito Fujisawa, Ryota Furukawa
  • Patent number: 9796179
    Abstract: A liquid discharge apparatus includes a controller, a drive signal generation unit, a discharge unit, a residual vibration detection unit, and an amplification unit, in which the controller generates discharge control data for controlling discharge of liquid and controls an amplification rate of an amplification unit, the drive signal generation unit generates and outputs a drive signal including a plurality of waveforms driving the discharge unit, the discharge unit discharges the liquid by applying a waveform assigned by the discharge control data among the plurality of waveforms included in the drive signal, the residual vibration detection unit detects residual vibration of the discharge unit and outputs a residual vibration signal indicating the residual vibration, after the discharge unit is driven by the drive signal, and the amplification unit amplifies the residual vibration signal with the amplification rate controlled by the controller and outputs the amplified signal.
    Type: Grant
    Filed: July 19, 2016
    Date of Patent: October 24, 2017
    Assignee: Seiko Epson Corporation
    Inventors: Kyohei Date, Masashi Kamiyanagi, Ryota Furukawa, Kazuhito Fujisawa, Hiroshi Sugita
  • Patent number: 9724914
    Abstract: A liquid discharging apparatus includes a first piezoelectric element that includes a pair of electrodes including a first electrode and that is displaced according to a potential change of a driving signal in a case where the driving signal is supplied to the first electrode, a reference piezoelectric element that includes a pair of electrodes including a reference electrode, an internal space of which a volume changes in response to displacement of the reference piezoelectric element, and a detecting unit that detects a potential of the first electrode via a first wire and detects a potential of the reference electrode via a second wire in a first detection period which is a period after the first piezoelectric element is displaced due to the driving signal, in which the internal space is not filled with the liquid.
    Type: Grant
    Filed: December 1, 2016
    Date of Patent: August 8, 2017
    Assignee: Seiko Epson Corporation
    Inventor: Kazuhito Fujisawa
  • Publication number: 20170182773
    Abstract: A head unit includes a discharge section, a determination circuit, and a discharge limitation circuit. The discharge section is equipped with a piezoelectric element that is configured to be displaced in accordance with changes in potential of a drive signal when the drive signal is supplied. The discharge section is configured to discharge a liquid in accordance with displacement of the piezoelectric element. The determination circuit is configured to determine whether or not the piezoelectric element has a predetermined power storage capability. The discharge limitation circuit is configured to stop supply of the drive signal to the piezoelectric element and limit discharging of liquid from the discharge section when a result of determination is negative.
    Type: Application
    Filed: November 28, 2016
    Publication date: June 29, 2017
    Inventors: Kazuhito FUJISAWA, Ryota FURUKAWA
  • Publication number: 20170173948
    Abstract: A liquid discharging apparatus includes a first piezoelectric element that includes a pair of electrodes including a first electrode and that is displaced according to a potential change of a driving signal in a case where the driving signal is supplied to the first electrode, a reference piezoelectric element that includes a pair of electrodes including a reference electrode, an internal space of which a volume changes in response to displacement of the reference piezoelectric element, and a detecting unit that detects a potential of the first electrode via a first wire and detects a potential of the reference electrode via a second wire in a first detection period which is a period after the first piezoelectric element is displaced due to the driving signal, in which the internal space is not filled with the liquid.
    Type: Application
    Filed: December 1, 2016
    Publication date: June 22, 2017
    Inventor: Kazuhito FUJISAWA
  • Publication number: 20170021615
    Abstract: A liquid discharge apparatus includes a controller, a drive signal generation unit, a discharge unit, a residual vibration detection unit, and an amplification unit, in which the controller generates discharge control data for controlling discharge of liquid and controls an amplification rate of an amplification unit, the drive signal generation unit generates and outputs a drive signal including a plurality of waveforms driving the discharge unit, the discharge unit discharges the liquid by applying a waveform assigned by the discharge control data among the plurality of waveforms included in the drive signal, the residual vibration detection unit detects residual vibration of the discharge unit and outputs a residual vibration signal indicating the residual vibration, after the discharge unit is driven by the drive signal, and the amplification unit amplifies the residual vibration signal with the amplification rate controlled by the controller and outputs the amplified signal.
    Type: Application
    Filed: July 19, 2016
    Publication date: January 26, 2017
    Inventors: Kyohei DATE, Masashi KAMIYANAGI, Ryota FURUKAWA, Kazuhito FUJISAWA, Hiroshi SUGITA
  • Patent number: 9457563
    Abstract: An ink jet printer is provided with a driving signal generating section which generates a driving signal for driving a piezoelectric element, a residual vibration detecting section, a control IC which includes the residual vibration detecting section, and a connection terminal which connects the piezoelectric element, an input terminal to which the driving signal is supplied and an output terminal from which an output signal of the residual vibration detecting section is supplied, a first external wiring which is connected to the input terminal and through which the driving signal is supplied, and a second external wiring which is connected to the output terminal and through which the output signal of the residual vibration detecting section is supplied. A resistance value per unit length of the second external wiring is larger than a resistance value per unit length of the first external wiring.
    Type: Grant
    Filed: September 9, 2014
    Date of Patent: October 4, 2016
    Assignee: Seiko Epson Corporation
    Inventors: Yoshio Nakazawa, Masahiko Yoshida, Kazuhito Fujisawa, Atsushi Akiyama, Osamu Shinkawa
  • Patent number: 9434159
    Abstract: An ink jet printer is provided with a piezoelectric element which is provided corresponding to a pressure chamber in order to discharge liquid droplets, a driving signal generating section which generates a driving signal, a residual vibration detecting section which detects changes in an electromotive force of the piezoelectric element in accordance with the residual vibration inside the pressure chamber which occur after the driving signal is applied, a first switch which switches whether or not a driving signal is applied to the piezoelectric element, and a second switch which switches whether or not a change in the electromotive force is supplied to a first high-pass filter, where the second switch and the residual vibration detecting section are connected via a first capacitor of the first high-pass filter.
    Type: Grant
    Filed: August 12, 2014
    Date of Patent: September 6, 2016
    Assignee: Seiko Epson Corporation
    Inventors: Yoshio Nakazawa, Kazuhito Fujisawa, Masahiko Yoshida, Atsushi Akiyama, Osamu Shinkawa
  • Publication number: 20150091960
    Abstract: An ink jet printer is provided with a driving signal generating section which generates a driving signal for driving a piezoelectric element, a residual vibration detecting section, a control IC which includes the residual vibration detecting section, and a connection terminal which connects the piezoelectric element, an input terminal to which the driving signal is supplied and an output terminal from which an output signal of the residual vibration detecting section is supplied, a first external wiring which is connected to the input terminal and through which the driving signal is supplied, and a second external wiring which is connected to the output terminal and through which the output signal of the residual vibration detecting section is supplied. A resistance value per unit length of the second external wiring is larger than a resistance value per unit length of the first external wiring.
    Type: Application
    Filed: September 9, 2014
    Publication date: April 2, 2015
    Inventors: Yoshio NAKAZAWA, Masahiko YOSHIDA, Kazuhito FUJISAWA, Atsushi AKIYAMA, Osamu SHINKAWA
  • Publication number: 20150054876
    Abstract: An ink jet printer is provided with a piezoelectric element which is provided corresponding to a pressure chamber in order to discharge liquid droplets, a driving signal generating section which generates a driving signal, a residual vibration detecting section which detects changes in an electromotive force of the piezoelectric element in accordance with the residual vibration inside the pressure chamber which occur after the driving signal is applied, a first switch which switches whether or not a driving signal is applied to the piezoelectric element, and a second switch which switches whether or not a change in the electromotive force is supplied to a first high-pass filter, where the second switch and the residual vibration detecting section are connected via a first capacitor of the first high-pass filter.
    Type: Application
    Filed: August 12, 2014
    Publication date: February 26, 2015
    Inventors: Yoshio NAKAZAWA, Kazuhito FUJISAWA, Masahiko YOSHIDA, Atsushi AKIYAMA, Osamu SHINKAWA
  • Patent number: 8807720
    Abstract: A printing apparatus includes a holder in which a cartridge set that is configured of N printing material cartridges is mounted and a mounting detection circuit for detecting a mounting state of the printing material cartridge inside the holder. Each of N printing material cartridges has a storage device for storing information regarding the contained printing material, an electric device for the mounting detection, storage device terminals and the electric device terminals. The electric device for N printing material cartridges is configured such that the detection current is predetermined threshold value current or more when N printing material cartridges are all mounted inside the holder.
    Type: Grant
    Filed: September 1, 2011
    Date of Patent: August 19, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhito Fujisawa, Shuichi Nakano
  • Patent number: 8622506
    Abstract: A printing device includes: a printing material container that includes first and second short circuit detection terminals, first and second attachment detection terminals; a high voltage power supply that applies a high voltage to the first attachment detection terminal; a short circuit detector that detects a short circuit between at least one of the first and second short circuit detection terminals and at least one of the first and second attachment detection terminals; a high voltage application controller that blocks supply of the high voltage from the high voltage power supply when the short circuit detector detects the short circuit; a resistor element that is arranged between the high voltage power supply and the first attachment detection terminal; and an electrostatic capacitor element that is arranged between the detection node of the short circuit detector and a low-potential-side power supply node.
    Type: Grant
    Filed: May 25, 2012
    Date of Patent: January 7, 2014
    Assignee: Seiko Epson Corporation
    Inventor: Kazuhito Fujisawa
  • Publication number: 20120306948
    Abstract: A printing device includes: a printing material container that includes first and second short circuit detection terminals, first and second attachment detection terminals; a high voltage power supply that applies a high voltage to the first attachment detection terminal; a short circuit detector that detects a short circuit between at least one of the first and second short circuit detection terminals and at least one of the first and second attachment detection terminals; a high voltage application controller that blocks supply of the high voltage from the high voltage power supply when the short circuit detector detects the short circuit; a resistor element that is arranged between the high voltage power supply and the first attachment detection terminal; and an electrostatic capacitor element that is arranged between the detection node of the short circuit detector and a low-potential-side power supply node.
    Type: Application
    Filed: May 25, 2012
    Publication date: December 6, 2012
    Applicant: Seiko Epson Corporation
    Inventor: Kazuhito FUJISAWA