Patents by Inventor Daisuke Okumura

Daisuke Okumura 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: 9589781
    Abstract: A curved ion guide includes four curved rod electrodes arranged around a curved central axis, two deflecting auxiliary electrodes which face each other across the axis, and two focusing auxiliary electrodes which are located on a curved surface orthogonal to the plane P and including the axis and which face each other across the axis. Ions are focused by the effect of an electric field created by radio-frequency voltages applied to the curved rod electrodes, and a deflecting electric field having the effect of curving ions along the axis is created by direct-current voltages applied to the deflecting auxiliary electrodes. Furthermore, a focusing direct-current electric field having the effect of pushing ions from the vicinity of the focusing auxiliary electrodes toward the axis is created by a direct-current voltage having the same polarity as that of the ions and applied to the focusing auxiliary electrodes.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: March 7, 2017
    Assignee: Shimadzu Corporation
    Inventor: Daisuke Okumura
  • Patent number: 9373490
    Abstract: When ions introduced between repeller electrode and extraction electrode are accelerated through flight space, orthogonal acceleration power supply portion applies a designated voltage to a plurality of acceleration electrodes in such a way as to form an acceleration field wherein potential distribution ? along central axis of the acceleration area becomes ?2?/?Z2<0. When ions traverse an acceleration field with this manner of axial potential distribution, in addition to force in the acceleration direction, force pressing towards central axis acts on ions situated away from central axis. This causes ions to be fired through flight space while being focused, and hence to reach detector more efficiently. This makes it possible to improve measurement sensitivity without adding a focusing lens or the like.
    Type: Grant
    Filed: June 19, 2015
    Date of Patent: June 21, 2016
    Assignee: SHIMADZU CORPORATION
    Inventors: Masaru Nishiguchi, Daisuke Okumura
  • Publication number: 20160163527
    Abstract: In the ionizer of the present invention, a stream of gas spouted from a nozzle (18) of a DART ionization unit (10) vaporizes and ionizes the components in a sample (25). Gaseous sample-component molecules which have not been ionized by that process are subsequently ionized by a reaction with a reactant ion produced by a corona discharge generated from a needle electrode (20). Such a two-stage ionization of the sample-component molecules improves the ionization efficiency. A needle-electrode support mechanism (21) adjusts the position and/or angle of the needle electrode (20) and thereby controls a potential gradient. Therefore, a specific sample-derived ion species can be efficiently introduced into an ion introduction tube (31) and be detected with a high level of sensitivity.
    Type: Application
    Filed: August 2, 2013
    Publication date: June 9, 2016
    Applicants: SHIMADZU CORPORATION, Public University Corporation Yokohama City Univer sity
    Inventors: Kanako SEKIMOTO, Mitsuo TAKAYAMA, Daisuke OKUMURA
  • Patent number: 9324551
    Abstract: A method of operating an electrode changeover switch which switches the connection state of electrodes, the electrode changeover switch is provided in the wiring path between eight electrodes through, arranged rotation-symmetrically about ion optical axis, and voltage generation switch which generates square wave high voltage ±V. When switch is switched as shown in the drawing, two circumferentially adjacent rod electrodes are connected to form one set, a square wave voltage of opposite phase is applied to circumferentially adjacent sets, and an effectively quadrupole electric field is formed. When switch is switched, a square wave voltage of opposite phase is applied to circumferentially adjacent rod electrodes and an octupole electric field is formed. In this way, by switching the switch according to the mass range, etc., it becomes possible to rapidly switch the number of poles of a multipole electric field and to suitably transport ions.
    Type: Grant
    Filed: August 25, 2014
    Date of Patent: April 26, 2016
    Assignee: SHIMADZU CORPORATION
    Inventors: Junichi Taniguchi, Daisuke Okumura, Hiroto Itoi
  • Patent number: 9230788
    Abstract: In eight electrodes arranged at an interval of a rotational angle of 45° around an ion optical axis, two neighboring electrodes are electrically connected together as one group, and electrodes in alternate groups are also electrically connected together. A voltage VDC+v cos ?t is applied to electrodes in alternate groups around the optical axis, and a voltage VDC?v cos ?t is applied to the other electrodes. Then, while an ion guide has the same electrode structure as that of an octupole-type ion guide, a radio-frequency electric field mainly having a quadrupole field component is formed, and the ion guide can be used as a quadrupole-type ion guide. Accordingly, only by changing the wiring for applying a voltage by using the electrodes having the same structure, ion guides of, for example, a quadrupole type and an octupole type, having different properties such as ion receiving properties and ion passing properties can be achieved.
    Type: Grant
    Filed: March 16, 2012
    Date of Patent: January 5, 2016
    Assignee: SHIMADZU CORPORATION
    Inventors: Daisuke Okumura, Hiroto Itoi
  • Patent number: 9040902
    Abstract: In an atmospheric pressure ionization source using an ESI or the like having a desolvation pipe with one end opening serving as an ion-drawing port, a drying-gas supplying port for supplying a drying gas against the ion-drawing direction is provided below the ion-drawing port, i.e. at a position opposite to the side where a nozzle for spraying a liquid sample into an atmospheric pressure atmosphere is located, as viewed from the ion-drawing port. When the drying gas is supplied from the drying-gas supplying port, the gas pressure becomes higher in a region above the ion-drawing port becomes higher than in a region below the same port and produces a downward air stream. This stream helps ions in the spray flow from the nozzle to easily come close to the ion-drawing port and be efficiently drawn into the desolvation pipe.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: May 26, 2015
    Assignee: SHIMADZU CORPORATION
    Inventors: Manabu Ueda, Daisuke Okumura
  • Publication number: 20150041642
    Abstract: In eight electrodes arranged at an interval of a rotational angle of 45° around an ion optical axis, two neighboring electrodes are electrically connected together as one group, and electrodes in alternate groups are also electrically connected together. A voltage VDC+v cos ?t is applied to electrodes in alternate groups around the optical axis, and a voltage VDC?v cos ?t is applied to the other electrodes. Then, while an ion guide has the same electrode structure as that of an octupole-type ion guide, a radio-frequency electric field mainly having a quadrupole field component is formed, and the ion guide can be used as a quadrupole-type ion guide. Accordingly, only by changing the wiring for applying a voltage by using the electrodes having the same structure, ion guides of, for example, a quadrupole type and an octupole type, having different properties such as ion receiving properties and ion passing properties can be achieved.
    Type: Application
    Filed: March 16, 2012
    Publication date: February 12, 2015
    Applicant: SHIMADZU CORPORATION
    Inventors: Daisuke Okumura, Hiroto Itoi
  • Publication number: 20140361163
    Abstract: A method of operating an electrode changeover switch which switches the connection state of electrodes, the electrode changeover switch is provided in the wiring path between eight electrodes through, arranged rotation-symmetrically about ion optical axis, and voltage generation switch which generates square wave high voltage ±V. When switch is switched as shown in the drawing, two circumferentially adjacent rod electrodes are connected to form one set, a square wave voltage of opposite phase is applied to circumferentially adjacent sets, and an effectively quadrupole electric field is formed. When switch is switched, a square wave voltage of opposite phase is applied to circumferentially adjacent rod electrodes and an octupole electric field is formed. In this way, by switching the switch according to the mass range, etc., it becomes possible to rapidly switch the number of poles of a multipole electric field and to suitably transport ions.
    Type: Application
    Filed: August 25, 2014
    Publication date: December 11, 2014
    Applicant: SHIMADZU CORPORATION
    Inventors: Junichi TANIGUCHI, Daisuke OKUMURA, Hiroto ITOI
  • Patent number: 8866077
    Abstract: A mass spectrometer having a multi-stage differential pumping system with an ion lens provided in a partition wall separating a second intermediate vacuum chamber and a third intermediate vacuum chamber, the incircle radii of ion guides and the size of the opening of the ion lens are determined so that the circumferential edge of the opening is located outside the circumferential surface of a virtual tubular body straightly connecting the incircle at the rear edge of the second ion guide in the front stage and the incircle at the front edge of the third ion guide in the rear stage. Although the ion lens is located in between, the radio-frequency electric field created by the second ion guide can be effectively connected to the radio-frequency electric field created by the third ion guide through the opening of the ion lens.
    Type: Grant
    Filed: October 20, 2011
    Date of Patent: October 21, 2014
    Assignee: Shimadzu Corporation
    Inventors: Daisuke Okumura, Manabu Ueda
  • Patent number: 8866074
    Abstract: An ion trap is provided between a collision cell and a time-of-flight mass separator. During a time period in which precursor ions derived from the same compound are selected with a quadrupole mass filter, a collision energy is changed from one to another. Various product ions that are produced by dissociation respectively under collision energies of the plurality of stages and precursor ions that are not dissociated are temporarily trapped in the ion trap, and are ejected in a packet form in the state where these ions are mixed, and are introduced into the time-of-flight mass separator 6 to be subjected to a mass spectrometry. Thereby, in a data processing unit, one MS/MS spectrum in which product ions produced in various dissociation modes under various CID conditions appear is created.
    Type: Grant
    Filed: February 24, 2014
    Date of Patent: October 21, 2014
    Assignee: Shimadzu Corporation
    Inventor: Daisuke Okumura
  • Publication number: 20140284473
    Abstract: In an atmospheric pressure ionization source using an ESI or the like having a desolvation pipe with one end opening serving as an ion-drawing port, a drying-gas supplying port for supplying a drying gas against the ion-drawing direction is provided below the ion-drawing port, i.e. at a position opposite to the side where a nozzle for spraying a liquid sample into an atmospheric pressure atmosphere is located, as viewed from the ion-drawing port. When the drying gas is supplied from the drying-gas supplying port, the gas pressure becomes higher in a region above the ion-drawing port becomes higher than in a region below the same port and produces a downward air stream. This stream helps ions in the spray flow from the nozzle to easily come close to the ion-drawing port and be efficiently drawn into the desolvation pipe.
    Type: Application
    Filed: October 17, 2011
    Publication date: September 25, 2014
    Applicant: SHIMADZU CORPORATION
    Inventors: Manabu Ueda, Daisuke Okumura
  • Publication number: 20140252217
    Abstract: A mass spectrometer having a multi-stage differential pumping system with an ion lens provided in a partition wall separating a second intermediate vacuum chamber and a third intermediate vacuum chamber, the incircle radii of ion guides and the size of the opening of the ion lens are determined so that the circumferential edge of the opening is located outside the circumferential surface of a virtual tubular body straightly connecting the incircle at the rear edge of the second ion guide in the front stage and the incircle at the front edge of the third ion guide in the rear stage. Although the ion lens is located in between, the radio-frequency electric field created by the second ion guide can be effectively connected to the radio-frequency electric field created by the third ion guide through the opening of the ion lens.
    Type: Application
    Filed: October 20, 2011
    Publication date: September 11, 2014
    Applicant: SHIMADZU CORPORATION
    Inventors: Daisuke Okumura, Manabu Ueda
  • Patent number: 8822915
    Abstract: In a first-stage intermediate vacuum chamber, cluster ions causing a background noise are dominantly formed in area (A), while fragment ions are dominantly generated in area (B). Taking this fact into account, when no in-source CID analysis is performed, voltages applied to the first-stage plate electrode of an ion guide and the exit end of a desolvation tube are adjusted to create an accelerating electric field only in area (A) without creating such a field in area (B). Meanwhile, voltages applied to the electrodes of the ion guide are adjusted to create an electric field for separating ions according to their mobility and selecting a specific ion. Such an operation suppresses the cluster-ion formation, removes ions which originate from impurities and have mass-to-charge ratios close to or equal to those of the ions originating from a target substance, and suppresses the fragment-ion generation. As a result, the target ions are detected with high S/N.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: September 2, 2014
    Assignee: Shimadzu Corporation
    Inventors: Kazuo Mukaibatake, Daisuke Okumura
  • Publication number: 20140239170
    Abstract: An ion trap is provided between a collision cell and a time-of-flight mass separator. During a time period in which precursor ions derived from the same compound are selected with a quadrupole mass filter, a collision energy is changed from one to another. Various product ions that are produced by dissociation respectively under collision energies of the plurality of stages and precursor ions that are not dissociated are temporarily trapped in the ion trap, and are ejected in a packet form in the state where these ions are mixed, and are introduced into the time-of-flight mass separator 6 to be subjected to a mass spectrometry. Thereby, in a data processing unit, one MS/MS spectrum in which product ions produced in various dissociation modes under various CID conditions appear is created.
    Type: Application
    Filed: February 24, 2014
    Publication date: August 28, 2014
    Applicant: SHIMADZU CORPORATION
    Inventor: Daisuke OKUMURA
  • Patent number: 8748811
    Abstract: A mass analysis of a sample having a known mass-to-charge ratio is carried out by performing a scan at a first-stage quadrupole over a predetermined mass range, under the condition that a collision induced dissociation gas is introduced into a collision cell and a voltage applied to a third-stage quadrupole is set so that no substantial mass separation occurs in this quadrupole. Various product ions originating from a precursor ion selected by the first-stage quadrupole arrive at and are detected by a detector without being mass separated. Accordingly, based on the detection data, a data processor can obtain a relationship between the voltage applied to the first-stage quadrupole and the mass-to-charge ratio of the selected ions, with a time delay in the collision cell reflected in that relationship. This relationship is stored in a calibration data memory, to be utilized in a neutral loss scan measurement or the like.
    Type: Grant
    Filed: August 20, 2012
    Date of Patent: June 10, 2014
    Assignee: Shimadzu Corporation
    Inventor: Daisuke Okumura
  • Publication number: 20140103206
    Abstract: In a first-stage intermediate vacuum chamber, cluster ions causing a background noise are dominantly formed in area (A), while fragment ions are dominantly generated in area (B). Taking this fact into account, when no in-source CID analysis is performed, voltages applied to the first-stage plate electrode of an ion guide and the exit end of a desolvation tube are adjusted to create an accelerating electric field only in area (A) without creating such a field in area (B). Meanwhile, voltages applied to the electrodes of the ion guide are adjusted to create an electric field for separating ions according to their mobility and selecting a specific ion. Such an operation suppresses the cluster-ion formation, removes ions which originate from impurities and have mass-to-charge ratios close to or equal to those of the ions originating from a target substance, and suppresses the fragment-ion generation. As a result, the target ions are detected with high S/N.
    Type: Application
    Filed: December 17, 2013
    Publication date: April 17, 2014
    Inventors: Kazuo Mukaibatake, Daisuke Okumura
  • Patent number: 8698074
    Abstract: The gas conductance on the ion injection side of a collision cell is made larger than the gas conductance on the ion exit side by providing two ion injection apertures 23, 25 in the collision cell. Due to the different gas conductances, a CID gas supplied through the gas supply tube 31 generally flows in a direction from the ion injection side to the ion exit side in the collision cell, namely, in the ion's passage direction. When the ions injected in the collision cell 20 slow down upon contacting with the CID gas, their progress is assisted by the gas flow, so that the delay of the ions in the collision cell 20 is alleviated. As a result, it is possible to avoid a deterioration in the detection sensitivity of a target product ion and to prevent a ghost peak caused by the stay of the ions.
    Type: Grant
    Filed: April 25, 2012
    Date of Patent: April 15, 2014
    Assignee: Shimadzu Corporation
    Inventors: Hiroto Itoi, Daisuke Okumura
  • Patent number: 8698072
    Abstract: A high-quality mass spectrum is provided with alleviated mass/charge axis deviation in a triple quadrupole mass spectrometer even when executing a high-speed mass scan with MS/MS analysis. Mass calibration tables which denote relations between m/z and a mass deviation value which scan speed is a parameter are prepared separately for use in MS analyses without involving dissociation operations and MS/MS analyses with involving dissociation operations. According to a measuring mode, such as a product ion scan measurement or a neutral loss scan measurement, when performing MS/MS analysis, a mass deviation value for the minimum scan speed in a table is used for a quadrupole where the selected m/z is fixed, and a mass deviation value for a designated scan speed in a table is used for a quadrupole where the mass scan is performed, thus controlling the operations of each of a pre-stage and a post-stage quadrupoles.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: April 15, 2014
    Assignee: Shimadzu Corporation
    Inventors: Hiroshi Sugawara, Daisuke Okumura
  • Patent number: 8637810
    Abstract: In a first-stage intermediate vacuum chamber, cluster ions causing a background noise are dominantly formed in area (A), while fragment ions are dominantly generated in area (B). Taking this fact into account, in an in-source CID analysis mode, a DC voltage higher than that applied to a skimmer is applied to a first ion guide so as to create an accelerating electric field in area (B), whereby the ions are sufficiently energized to promote the fragmentation. When the in-source CID is not performed, a DC voltage higher than that applied to the first ion guide is applied to the exit end of a desolvation tube so as to create an accelerating electric field only in area (A) without creating such a field in area (B), whereby both the formation of the cluster ions and the generation of the fragment ions are suppressed, so that a high-quality chromatogram can be obtained.
    Type: Grant
    Filed: June 24, 2010
    Date of Patent: January 28, 2014
    Assignee: Shimadzu Corporation
    Inventors: Kazuo Mukaibatake, Daisuke Okumura
  • Publication number: 20130334415
    Abstract: A high-quality mass spectrum is provided with alleviated mass/charge axis deviation in a triple quadrupole mass spectrometer even when executing a high-speed mass scan with MS/MS analysis. Mass calibration tables which denote relations between m/z and a mass deviation value which scan speed is a parameter are prepared separately for use in MS analyses without involving dissociation operations and MS/MS analyses with involving dissociation operations. According to a measuring mode, such as a product ion scan measurement or a neutral loss scan measurement, when performing MS/MS analysis, a mass deviation value for the minimum scan speed in a table is used for a quadrupole where the selected m/z is fixed, and a mass deviation value for a designated scan speed in a table is used for a quadrupole where the mass scan is performed, thus controlling the operations of each of a pre-stage and a post-stage quadrupoles.
    Type: Application
    Filed: September 30, 2011
    Publication date: December 19, 2013
    Applicant: SHIMADZU CORPORATION
    Inventors: Hiroshi Sugawara, Daisuke Okumura