Patents by Inventor Kenji Mawatari

Kenji Mawatari 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: 20210094290
    Abstract: The present invention discharges ink from a plurality of inkjet heads and is used when performing drive whereby one droplet or a plurality of droplets are discharged onto and united on one pixel. A drive signal includes a drive waveform comprising N number (N being an integer of at least 2) of drive waveform elements and is configured so as to fulfil the relationship 1.1 Tc?Ts?1.4 Tc, when Tc is the natural vibration cycle determined from the inkjet head structure and Ts is the time from the start point of the drive waveform to the start point of the subsequent drive waveform. As a result, velocity deviation caused by the resonant frequency of a piezoelectric actuator driving the inkjet head can be suppressed when driving an inkjet head using multiple gradations.
    Type: Application
    Filed: October 4, 2018
    Publication date: April 1, 2021
    Inventor: Kenji MAWATARI
  • Patent number: 10639890
    Abstract: An inkjet head configured to eject inkjet ink includes a piezoelectric layer of a thin film and a diaphragm. An absolute value of a product of a piezoelectric constant d31 of the piezoelectric layer and a Young's modulus of the piezoelectric layer is 10 [C/m2] to 15 [C/m2]. Even when the inkjet head ejects ink having a high viscosity, variation of driving voltage during ejection can be suppressed.
    Type: Grant
    Filed: October 26, 2016
    Date of Patent: May 5, 2020
    Assignee: KONICA MINOLTA, INC.
    Inventor: Kenji Mawatari
  • Patent number: 10369787
    Abstract: A piezoelectric thin film is formed by adding a donor element to lead zirconate titanate. In the piezoelectric thin film, a molar ratio of lead to a total sum of zirconium and titanium is 105% or higher, and, when positive and negative coercive electric fields in polarization and electric field hysteresis are referred to as Ec (+) and Ec (?), respectively, a value of |Ec (+) |/|Ec (?) | is 0.5 or more and 1.5 or less.
    Type: Grant
    Filed: May 11, 2016
    Date of Patent: August 6, 2019
    Assignee: KONICA MINOLTA, INC.
    Inventor: Kenji Mawatari
  • Publication number: 20180326727
    Abstract: An inkjet head configured to eject inkjet ink includes a piezoelectric layer of a thin film and a diaphragm. An absolute value of a product of a piezoelectric constant d31 of the piezoelectric layer and a Young's modulus of the piezoelectric layer is 10 [C/m2] to 15 [C/m2]. Even when the inkjet head ejects ink having a high viscosity, variation of driving voltage during ejection can be suppressed.
    Type: Application
    Filed: October 26, 2016
    Publication date: November 15, 2018
    Inventor: Kenji MAWATARI
  • Publication number: 20180170044
    Abstract: A piezoelectric thin film is formed by adding a donor element to lead zirconate titanate. In the piezoelectric thin film, a molar ratio of lead to a total sum of zirconium and titanium is 105% or higher, and, when positive and negative coercive electric fields in polarization and electric field hysteresis are referred to as Ec (+) and Ec (?), respectively, a value of |Ec (+)|/|Ec (?)| is 0.5 or more and 1.5 or less.
    Type: Application
    Filed: May 11, 2016
    Publication date: June 21, 2018
    Inventor: Kenji MAWATARI
  • Patent number: 9705070
    Abstract: In order to obtain a ferroelectric thin film that is formed to have a predetermined thickness on a substrate, that have satisfactory crystallization and that achieves a high piezoelectric property, a method of manufacturing such a ferroelectric thin film and a method of manufacturing a piezoelectric element having such a ferroelectric thin film, when a dielectric material of a perovskite structure is formed into a film on the substrate, a predetermined amount of additive is mixed with PZT, and the concentration of the additive mixed is varied in the thickness direction of the thin film.
    Type: Grant
    Filed: October 26, 2011
    Date of Patent: July 11, 2017
    Assignee: KONICA MINOLTA, INC.
    Inventor: Kenji Mawatari
  • Publication number: 20170050439
    Abstract: This ferroelectric thin film comprises lead zirconate titanate niobate. In said ferroelectric thin film, the ratio (a) of number of moles of lead to the total number of moles of zirconium, titanium, and niobium is greater than or equal to 100%; the ratio (b) of the number of moles of niobium to the total number of moles of zirconium, titanium, and niobium is between 10% and 20%, inclusive; and the ratio (c) of the number of moles of zirconium to the total number of moles of zirconium and titanium is between 52% and 59%, inclusive. The film stress exhibited by the ferroelectric thin film is between 100 and 250 MPa, inclusive.
    Type: Application
    Filed: April 27, 2015
    Publication date: February 23, 2017
    Inventor: Kenji MAWATARI
  • Patent number: 9457564
    Abstract: A drive signal applied to a thin-film piezoelectric element includes the following: at least one discharge pulse that causes a drop of ink to be discharged from a pressure chamber; and a cancellation pulse. Said cancellation pulse has the same polarity as the discharge pulse(s) and serves to suppress reverberations of a pressure wave applied to the pressure chamber when the thin-film piezoelectric element is driven by the application of the discharge pulse(s). Letting Tc represent half of the natural vibration period of the pressure chamber, within the period within which a single pixel is placed, the cancellation pulse is applied once an amount of time equal to Tc times an even integer greater than or equal to 4 has passed since the end of the application of the first discharge pulse.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: October 4, 2016
    Assignee: KONICA MINOLTA, INC.
    Inventor: Kenji Mawatari
  • Patent number: 9324934
    Abstract: A piezoelectric thin film which is of a perovskite type having a tetragonal crystal structure, the tetragonal crystal having a degree of (100) orientation of 80% or higher. The piezoelectric thin film is constituted of a lead lanthanum zirconate titanate (PLZT) which is a lead zirconate titanate (PZT) in which some of the lead has been replaced with lanthanum.
    Type: Grant
    Filed: January 22, 2013
    Date of Patent: April 26, 2016
    Assignee: KONICA MINOLTA, INC.
    Inventor: Kenji Mawatari
  • Patent number: 9318687
    Abstract: A piezoelectric element having an electrode, a seed layer for controlling the crystal orientation of a piezoelectric layer, and the piezoelectric layer stacked in this order from the substrate side. The seed layer is composed of two or more layers stacked together each comprising crystals of spherical particles.
    Type: Grant
    Filed: July 25, 2013
    Date of Patent: April 19, 2016
    Assignee: KONICA MINOLTA, INC.
    Inventor: Kenji Mawatari
  • Publication number: 20160082723
    Abstract: A drive signal applied to a thin-film piezoelectric element includes the following: at least one discharge pulse that causes a drop of ink to be discharged from a pressure chamber; and a cancellation pulse. Said cancellation pulse has the same polarity as the discharge pulse(s) and serves to suppress reverberations of a pressure wave applied to the pressure chamber when the thin-film piezoelectric element is driven by the application of the discharge pulse(s). Letting Tc represent half of the natural vibration period of the pressure chamber, within the period within which a single pixel is placed, the cancellation pulse is applied once an amount of time equal to Tc times an even integer greater than or equal to 4 has passed since the end of the application of the first discharge pulse.
    Type: Application
    Filed: March 13, 2014
    Publication date: March 24, 2016
    Inventor: Kenji MAWATARI
  • Publication number: 20150214465
    Abstract: A piezoelectric element having an electrode, a seed layer for controlling the crystal orientation of a piezoelectric layer, and the piezoelectric layer stacked in this order from the substrate side. The seed layer is composed of two or more layers stacked together each comprising crystals of spherical particles.
    Type: Application
    Filed: July 25, 2013
    Publication date: July 30, 2015
    Applicant: KONICA MINOLTA, INC.
    Inventor: Kenji Mawatari
  • Publication number: 20150077474
    Abstract: A piezoelectric thin film which is of a perovskite type having a tetragonal crystal structure, the tetragonal crystal having a degree of (100) orientation of 80% or higher. The piezoelectric thin film is constituted of a lead lanthanum zirconate titanate (PLZT) which is a lead zirconate titanate (PZT) in which some of the lead has been replaced with lanthanum.
    Type: Application
    Filed: January 22, 2013
    Publication date: March 19, 2015
    Inventor: Kenji Mawatari
  • Publication number: 20130228454
    Abstract: In order to obtain a ferroelectric thin film that is formed to have a predetermined thickness on a substrate, that have satisfactory crystallization and that achieves a high piezoelectric property, a method of manufacturing such a ferroelectric thin film and a method of manufacturing a piezoelectric element having such a ferroelectric thin film, when a dielectric material of a perovskite structure is formed into a film on the substrate, a predetermined amount of additive is mixed with PZT, and the concentration of the additive mixed is varied in the thickness direction of the thin film.
    Type: Application
    Filed: October 26, 2011
    Publication date: September 5, 2013
    Inventor: Kenji Mawatari