Patents by Inventor Katsuhiro Oomori

Katsuhiro Oomori 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: 9950417
    Abstract: An electronic pulse driver includes a motor, a hammer, an anvil, an end tool mounting unit, a power supply unit, and a control unit. The hammer is rotatable together with the anvil. The end tool mounting unit transmits the rotation of the anvil to an end tool. The power supply unit supplies a drive electric power to the motor. The control unit controls the power supply unit to halt a supply of the drive electric power to the motor when an electric current flowing to the motor increases to a prescribed value. The control unit controls the power supply unit to supply to the motor a prestart electric power lower than the drive electric power before supplying the drive electric power in order to permit the power supply unit to supply the drive electric power after the hammer is in contact with the anvil.
    Type: Grant
    Filed: March 29, 2011
    Date of Patent: April 24, 2018
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yutaka Ito, Katsuhiro Oomori, Mizuho Nakamura, Tomomasa Nishikawa, Hironori Mashiko
  • Patent number: 9616558
    Abstract: According to an aspect of the present invention, there is provided an impact tool including: a motor; a hammer connected to an output portion of the motor; and an anvil to be struck by the hammer in a rotation direction and having a rotary shaft, the hammer striking the anvil in the rotation direction by driving the motor in pulses, wherein the anvil is provided in front of the hammer, wherein the hammer is driven in pulses by the motor, and wherein a rotation angle of the hammer is substantially proportional to a rotation angle of the motor.
    Type: Grant
    Filed: July 29, 2010
    Date of Patent: April 11, 2017
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Tomomasa Nishikawa, Nobuhiro Takano, Hideyuki Tanimoto, Kazutaka Iwata, Hironori Mashiko, Hayato Yamaguchi, Atsushi Nakagawa, Katsuhiro Oomori, Mizuho Nakamura, Hiroki Uchida, Saroma Nakano, Chikai Yoshimizu
  • Patent number: 9590475
    Abstract: According to an aspect of the invention, an electric power tool which includes a brushless direct-current motor and a drive circuit that supplies drive power to the motor, and which rotates or drives a tool, characterized in that the drive circuit includes plural switching elements, and is arranged on a board provided in a grip portion of a housing or below the grip portion; and an electric fan is provided in the vicinity of the switching element for cooling the switching element.
    Type: Grant
    Filed: December 13, 2013
    Date of Patent: March 7, 2017
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Katsuhiro Oomori, Junichi Tokairin, Hiroki Uchida
  • Patent number: 9522461
    Abstract: An impact tool (1) includes a motor (3); a hammer (42) having a rotational axis extending in a first direction, the hammer (42) being rotatable in a rotational direction including a forward direction and a reverse direction opposite to the forward direction by the motor (3) and being movable in the first direction and a second direction opposite to the first direction; an anvil (52) disposed at the first direction side of the hammer (42) and strikable by the hammer (42) in the forward direction, the hammer (42) that has been struck the anvil (52) being moved in the second direction to come free from the anvil (52); and a fixing member (45A, 46A) that selectively allows the hammer (42) to move in the second direction or prevents the hammer (42) from moving in the second direction.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: December 20, 2016
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Katsuhiro Oomori, Mizuho Nakamura, Yutaka Ito, Nobuhiro Takano, Tomomasa Nishikawa, Hironori Mashiko, Shigeru Takahashi
  • Patent number: 9391491
    Abstract: A power tool includes a housing, a brushless motor, and a cover member. The housing has an air intake hole and an air exhaust hole formed therein, the housing having an inner surface. The brushless motor has an outer surface disposed in the housing, a first endface near the air intake hole, and a second endface near the air exhaust hole. The cover member covers at least one of the first endface and the second endface for preventing dust from entering the brushless motor. The inner surface of the housing and outer surface of the brushless motor define a circulation path providing communication between the air intake hole and the air exhaust hole.
    Type: Grant
    Filed: September 20, 2013
    Date of Patent: July 12, 2016
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Kenichirou Yoshida, Katsuhiro Oomori, Yoshihiro Komuro, Kazutaka Iwata
  • Patent number: 9314908
    Abstract: According to an aspect of the present invention, there is provided an impact tool including: a motor drivable in an intermittent driving mode; a hammer connected to the motor; an anvil to be struck by the hammer to thereby rotate/strike a tip tool; and a control unit that controls a rotation of the motor by switching a driving pulse supplied to the motor in accordance with a load applied onto the tip tool.
    Type: Grant
    Filed: July 29, 2010
    Date of Patent: April 19, 2016
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Hideyuki Tanimoto, Nobuhiro Takano, Tomomasa Nishikawa, Kazutaka Iwata, Hironori Mashiko, Hayato Yamaguchi, Atsushi Nakagawa, Katsuhiro Oomori, Mizuho Nakamura, Hiroki Uchida, Saroma Nakano, Yutaka Ito
  • Patent number: 9126316
    Abstract: An electric tool including: a motor having a stator coil; and a circuit board, wherein the stator coil includes a coil main body and an extending part extending from the coil main body and electrically connected to the circuit board, and wherein the extending part is slacked.
    Type: Grant
    Filed: June 12, 2012
    Date of Patent: September 8, 2015
    Assignee: HITACHI KOKI CO., LTD.
    Inventor: Katsuhiro Oomori
  • Patent number: 9048699
    Abstract: According to an aspect of the present invention, there is provided a power tool including: a brushless motor; switching elements that drive the brushless motor; a circuit board on which the switching elements are mounted; a transmission portion that transmits a driving force of the brushless motor; and a housing that houses the brushless motor, the switching elements, the circuit board and the transmission portion therein, wherein the switching elements include semiconductor elements each having terminals on a bottom surface thereof, and wherein the switching elements are surface mounted on the circuit board.
    Type: Grant
    Filed: May 20, 2009
    Date of Patent: June 2, 2015
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Katsuhiro Oomori, Junichi Toukairin, Nobuhiro Takano, Kazutaka Iwata, Tomomasa Nishikawa
  • Publication number: 20140139055
    Abstract: According to an aspect of the invention, an electric power tool which includes a brushless direct-current motor and a drive circuit that supplies drive power to the motor, and which rotates or drives a tool, characterized in that the drive circuit includes plural switching elements, and is arranged on a board provided in a grip portion of a housing or below the grip portion; and an electric fan is provided in the vicinity of the switching element for cooling the switching element.
    Type: Application
    Filed: December 13, 2013
    Publication date: May 22, 2014
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Katsuhiro Oomori, Junichi Tokairin, Hiroki Uchida
  • Publication number: 20140124229
    Abstract: An impact tool has a hammer (5) to be driven by a motor for revolution and an anvil (6) impacted with the revolution by the hammer (5) and transmitting an impact force to a tip tool. Between the motor and the hammer (5), first and second ring gears (41A, 42A) are provided, and first and second planetary gear mechanisms (41) and (42) are arranged to transmit the rotary force of the motor to the hammer (5). The motor, the hammer (5), the anvil (6), and the first and second ring gears (41A, 42A) are accommodated in a housing (2). The second ring gear (42A) is movable between a holding position where the second ring gear (42A) is held as being engaged with the housing (2) and a non-holding position where the second ring gear (42A) is not engaged with the housing (2) and is revolvable with respect to the housing (2).
    Type: Application
    Filed: August 30, 2012
    Publication date: May 8, 2014
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Shigeru Takahashi, Katsuhiro Oomori
  • Publication number: 20140069672
    Abstract: A power tool includes: a motor configured to be driven based on one of a plurality of drive modes; a mode section switch; a control portion. The control portion is configured to operate responsive to a first operation to assign one or more drive modes preselected from the plurality of drive modes to the mode selection switch. A second operation different from the first operation is capable of manipulating the mode selection switch to select one drive mode from the one or more preselected drive modes, the control portion being further configured to control the motor based on the one drive mode selected by the mode selection switch.
    Type: Application
    Filed: March 21, 2012
    Publication date: March 13, 2014
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Hironori Mashiko, Nobuhiro Takano, Tomomasa Nishikawa, Atsushi Nakagawa, Masanori Watanabe, Mizuho Nakamura, Katsuhiro Oomori
  • Publication number: 20140015350
    Abstract: A power tool includes a housing, a brushless motor, and a cover member. The housing has an air intake hole and an air exhaust hole formed therein, the housing having an inner surface. The brushless motor has an outer surface disposed in the housing, a first endface near the air intake hole, and a second endface near the air exhaust hole. The cover member covers at least one of the first endface and the second endface for preventing dust from entering the brushless motor. The inner surface of the housing and outer surface of the brushless motor define a circulation path providing communication between the air intake hole and the air exhaust hole.
    Type: Application
    Filed: September 20, 2013
    Publication date: January 16, 2014
    Applicant: Hitachi KoKi Co., Ltd.
    Inventors: Kenichirou Yoshida, Katsuhiro Oomori, Yoshihiro Komuro, Kazutaka Iwata
  • Patent number: 8627900
    Abstract: An electric power tool (1) includes a brushless direct-current motor (3) and a drive circuit that supplies drive power to the motor, the power tool rotates or drives a tool, whereby the drive circuit includes plural switching elements (21), and is arranged on a board (9) provided in a grip portion of a housing or below the grip portion; and an electric fan (22) is provided in the vicinity of the switching element for cooling the switching element.
    Type: Grant
    Filed: May 20, 2009
    Date of Patent: January 14, 2014
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Katsuhiro Oomori, Junichi Toukairin, Hiroki Uchida
  • Publication number: 20130333910
    Abstract: According to one embodiment, an impact tool includes: a motor; and a hammer that is connected to the motor and that has a striking-side surface; and an anvil that is journalled to be rotatable with respect to the hammer, that has a struck-side surface and that provides a striking power to a tip tool, wherein the motor is drivable in: a first driving mode in which the motor is continuously driven in a normal rotation; a second driving mode in which the motor is intermittently driven only in the normal rotation; and a third driving mode in which the motor is intermittently driven in the normal rotation and in a reverse rotation.
    Type: Application
    Filed: July 29, 2010
    Publication date: December 19, 2013
    Applicant: HITACHI KOKI CO., LTD.,
    Inventors: Hideyuki Tanimoto, Nobuhiro Takano, Tomomasa Nishikawa, Kazutaka Iwata, Hironori Mashiko, Hayato Yamaguchi, Atsushi Nakagawa, Katsuhiro Oomori, Mizuho Nakamura, Hiroki Uchida, Saroma Nakano
  • Patent number: 8579042
    Abstract: A battery device is constituted by connecting such cell assemblies in parallel as each includes: a first cell group having a plurality of cells connected in series; a housing container for housing the first cell group; current detector housed in the container for detecting a current to flow through the first cell group; a switching element connected with the first cell group for turning ON/OFF the current to flow through the first cell group; and a controller for controlling the ON/OFF of the switching element in response to the output signal of the current detector.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: November 12, 2013
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Hiroyuki Hanawa, Kiyoshi Kato, Kazuhiko Funabashi, Katsuhiro Oomori
  • Publication number: 20130255981
    Abstract: In addition to improvement of operability, a small size with a light weight and a long life are achieved. A switch housing unit and a control-part housing unit are provided in a housing, a switch unit provided with a pressure switch which generates an electric signal by performing a pressing operation by a worker is housed in the switch housing unit, a switch cover which covers the pressure switch and which is elastically deformed by the pressing operation by the worker is provided, and the control-part houses a control circuit board which controls a rotation state of a motor in accordance with a magnitude of the electric signal outputted from the pressure switch.
    Type: Application
    Filed: February 15, 2013
    Publication date: October 3, 2013
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Keiko Noto, Katsuhiro Oomori
  • Publication number: 20130255982
    Abstract: A power tool, in which a case that is connected to a housing and the case houses a reducer mechanism that decelerates an output of an electric motor and an impact mechanism that transmits an output of the reducer mechanism to a tip tool, is provided. The power tool further includes an inner cover that covers an opening of the case, a ring gear included in the reducer mechanism, a spindle that is rotatably supported by a bearing, and a space portion that is placed between the inner cover and the ring gear and in a periphery of the bearing, and capable of stocking grease. A through hole, which communicates with the inside and outside of the case through the space portion, is formed in the inner cover.
    Type: Application
    Filed: February 15, 2013
    Publication date: October 3, 2013
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Shigeru Takahashi, Katsuhiro Oomori, Tomomasa Nishikawa
  • Patent number: 8541913
    Abstract: A power tool includes a housing, a brushless motor, and a cover member. The housing has an air intake hole and an air exhaust hole formed therein, the housing having an inner surface. The brushless motor has an outer surface disposed in the housing, a first endface near the air intake hole, and a second endface near the air exhaust hole. The cover member covers at least one of the first endface and the second endface for preventing dust from entering the brushless motor. The inner surface of the housing and outer surface of the brushless motor define a circulation path providing communication between the air intake hole and the air exhaust hole.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: September 24, 2013
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Kenichirou Yoshida, Katsuhiro Oomori, Yoshihiro Komuro, Kazutaka Iwata
  • Patent number: 8517558
    Abstract: A power tool includes a body housing a motor and a power transmission mechanism positioned ahead of the motor for transmitting a power of the motor, a handle grip having an upper end portion connected to an approximately intermediate portion of the body and a lower end portion to which a battery is connected, a light emitting element positioned below the power transmission mechanism and receiving electrical power from the battery for illuminating a portion ahead of the body, and a trigger positioned below the power transmission mechanism for controlling a supply of the electrical power from the battery to the motor and to the light emitting element.
    Type: Grant
    Filed: October 19, 2011
    Date of Patent: August 27, 2013
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Katsuhiro Oomori, Chikai Yoshimizu, Hidekazu Harada, Nobuhiro Takano
  • Publication number: 20130126202
    Abstract: An screw tightening tool (1) includes: a handle part (22) to be held by a user; a trigger (25); a power supplying section (6, 7) that supplies an electrical power in accordance with an operated amount of the trigger; and a motor (3) that rotates in accordance with the electrical power supplied from the power supplying section. The power supplying section supplies the motor with a preventing electrical power for preventing the motor from rotating with respect to the handle part when a predetermined condition is satisfied.
    Type: Application
    Filed: August 1, 2011
    Publication date: May 23, 2013
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Katsuhiro Oomori, Mizuho Nakamura, Yutaka Ito, Tomomasa Nishikawa, Hironori Mashiko, Atsushi Sumi, Takeshi takeda, Masayuki Ogura