Patents by Inventor Chikai Yoshimizu

Chikai Yoshimizu 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: 10547182
    Abstract: When a main switch (12) is turned ON, an electric operating machine (1) is put in the standby mode. With a trigger (13) being pulled in the standby mode, a power supply circuit (16) applies a voltage to a drive part (30). The power supply circuit (16) adjusts the voltage applied to the drive part (30) for a voltage corresponding to the pulling rate of the trigger (13). When the current running toward the drive part (30) exceeds the rated value of the drive part (30), the power supply circuit (16) automatically stops power supply to the drive part (30). On the other hand, when the output voltage of a battery (50) drops and the battery (50) is put in an overdischarge state, power supply to the drive part (30) is automatically stopped. When it is detected that the battery (50) undergoes an abnormal event, power supply to the drive part (30) is automatically stopped.
    Type: Grant
    Filed: February 10, 2017
    Date of Patent: January 28, 2020
    Assignee: KOKI HOLDINGS CO., LTD.
    Inventors: Nobuhiro Takano, Kazuhiko Funabashi, Hideyuki Tanimoto, Chikai Yoshimizu, Hiromi Ozawa, Yoshihiro Hoshi
  • Patent number: 10263228
    Abstract: The sealing property obtained when a battery pack is attached to an electric power tool is improved. An electric power tool to/from which a battery pack retaining a battery cell is attachable/detachable has: a tool main body being provided with an attachment part to/from which the battery pack is attached/detached; a guide groove which is provided in the attachment part and which determines a direction of the attachment/detachment of the battery pack; a device-side terminal which is provided in the attachment part and which is connected to a battery-side terminal provided in the battery pack; and a seal member which is provided in the attachment part and which seals a connecting part between the battery-side terminal and the device-side terminal.
    Type: Grant
    Filed: July 16, 2013
    Date of Patent: April 16, 2019
    Assignee: Koki Holdings Co., Ltd.
    Inventors: Tomomasa Nishikawa, Tetsuhiro Harada, Chikai Yoshimizu, Hiroyuki Hanawa
  • Publication number: 20170155258
    Abstract: When a main switch (12) is turned ON, an electric operating machine (1)is put in the standby mode. With a trigger (13) being pulled in the standby mode, a power supply circuit (16) applies a voltage to a drive part (30). The power supply circuit (16) adjusts the voltage applied to the drive part (30) for a voltage corresponding to the pulling rate of the trigger (13). When the current running toward the drive part (30) exceeds the rated value of the drive part (30), the power supply circuit (16) automatically stops power supply to the drive part (30). On the other hand, when the output voltage of a battery (50) drops and the battery (50) is put in an overdischarge state, power supply to the drive part (30) is automatically stopped. When it is detected that the battery (50) undergoes an abnormal event, power supply to the drive part (30) is automatically stopped.
    Type: Application
    Filed: February 10, 2017
    Publication date: June 1, 2017
    Inventors: Nobuhiro TAKANO, Kazuhiko FUNABASHI, Hideyuki TANIMOTO, Chikai YOSHIMIZU, Hiromi OZAWA, Yoshihiro HOSHI
  • 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
  • Publication number: 20160207187
    Abstract: A drilling device capable of easily pulling an end bit out of a workpiece is provided. The drilling device is provided with a housing, a brushless motor, a motion translating mechanism, and an output portion. The motion translating mechanism includes a rotation transmitting portion. The rotation transmitting portion includes a bevel gear and clutch. The bevel gear has an abutment portion. The clutches has an abutted portion. Rotational play is formed between the abutment portion and the abutted portion.
    Type: Application
    Filed: July 25, 2014
    Publication date: July 21, 2016
    Inventors: Tomomasa Nishikawa, Chikai Yoshimizu, Nobuhiro Takano
  • Patent number: 9160211
    Abstract: An electric grasscutter includes a motor (50) which drives a rotary blade (42). The motor (50) is a brushless motor accommodated in a motor housing (51) and including a rotor (53) provided integrally with an output shaft (52), and a stator (54) fixed to the motor housing (51). A motor control circuit which drives the motor (50) is accommodated in the motor housing (51). The motor control circuit includes an inverter having FETs (81-86) as switching elements, and a control section to control the FETs (81-86). The FETs (81-86) are fixed in contact with the motor housing (51).
    Type: Grant
    Filed: September 22, 2010
    Date of Patent: October 13, 2015
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Hideyuki Tanimoto, Chikai Yoshimizu, Nobuhiro Takano, Hiromi Ozawa, Kazuhiko Funabashi
  • Publication number: 20150214520
    Abstract: The sealing property obtained when a battery pack is attached to an electric power tool is improved. An electric power tool to/from which a battery pack retaining a battery cell is attachable/detachable has: a tool main body being provided with an attachment part to/from which the battery pack is attached/detached; a guide groove which is provided in the attachment part and which determines a direction of the attachment/detachment of the battery pack; a device-side terminal which is provided in the attachment part and which is connected to a battery-side terminal provided in the battery pack; and a seal member which is provided in the attachment part and which seals a connecting part between the battery-side terminal and the device-side terminal.
    Type: Application
    Filed: July 16, 2013
    Publication date: July 30, 2015
    Inventors: Tomomasa Nishikawa, Tetsuhiro Harada, Chikai Yoshimizu, Hiroyuki Hanawa
  • Patent number: 9065155
    Abstract: When a battery pack having an output voltage of 14.4 V that is connectable to an electric tool in a sliding manner is used as a power supply source for the electric tool that is connectable to a battery pack in an insertion manner and has a rated voltage of 12 V, the electric tool and the battery pack are connected to each other with an adaptor interposed therebetween. The adaptor has an FET that is switched at a predetermined duty of a predetermined frequency. The battery pack and the electric tool are connected or disconnected to or from each other by the switching operation, thereby dropping the output voltage of the battery pack. When the detected voltage is out of a predetermined value range, it is judged that the overcurrent or overdischarge has occurred. Then, the FET is turned off to stop the electric tool.
    Type: Grant
    Filed: June 22, 2012
    Date of Patent: June 23, 2015
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Nobuhiro Takano, Yoshikazu Kawano, Kazuhiko Funabashi, Yuuichi Konuma, Masateru Niyada, Chikai Yoshimizu, Eiji Nakayama, Kenro Ishimaru
  • Patent number: 8928201
    Abstract: A motor has an output shaft which is rotatably supported by a housing, a rotor which is fixed to the output shaft and which comprises a printed-wiring board, and a stator which is fixed to the housing and which comprises a magnet facing the rotor. The printed-wiring board comprises a coil/commutator disk and a coil disk. A commutator conductor pattern is formed in a commutator region of the coil/commutator disk. Likewise, coil conductor patterns are formed in respective coil regions of the coil/commutator disk and of the coil disk.
    Type: Grant
    Filed: September 22, 2010
    Date of Patent: January 6, 2015
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Hideyuki Tanimoto, Chikai Yoshimizu, Nobuhiro Takano, Hiromi Ozawa, Kazuhiko Funabashi
  • 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: 20120262035
    Abstract: When a battery pack having an output voltage of 14.4 V that is connectable to an electric tool in a sliding manner is used as a power supply source for the electric tool that is connectable to a battery pack in an insertion manner and has a rated voltage of 12 V, the electric tool and the battery pack are connected to each other with an adaptor interposed therebetween. The adaptor has an FET that is switched at a predetermined duty of a predetermined frequency. The battery pack and the electric tool are connected or disconnected to or from each other by the switching operation, thereby dropping the output voltage of the battery pack. When the detected voltage is out of a predetermined value range, it is judged that the overcurrent or overdischarge has occurred. Then, the FET is turned off to stop the electric tool.
    Type: Application
    Filed: June 22, 2012
    Publication date: October 18, 2012
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Nobuhiro TAKANO, Yoshikazu Kawano, Kazuhiko Funabashi, Yuuichi Konuma, Masateru Niyada, Chikai Yoshimizu, Eiji Nakayama, Kenro Ishimaru
  • Publication number: 20120199372
    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: Application
    Filed: July 29, 2010
    Publication date: August 9, 2012
    Applicant: 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: 8237404
    Abstract: When a battery pack having an output voltage of 14.4 V that is connectable to an electric tool in a sliding manner is used as a power supply source for the electric tool that is connectable to a battery pack in an insertion manner and has a rated voltage of 12 V, the electric tool and the battery pack are connected to each other with an adaptor interposed therebetween. The adaptor has an FET that is switched at a predetermined duty of a predetermined frequency. The battery pack and the electric tool are connected or disconnected to or from each other by the switching operation, thereby dropping the output voltage of the battery pack. The voltage from the battery pack is detected. When the detected voltage is out of a predetermined value range, it is judged that the overcurrent or overdischarge has occurred. Then, the FET is turned off to stop the electric tool.
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: August 7, 2012
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Nobuhiro Takano, Yoshikazu Kawano, Kazuhiko Funabashi, Yuuichi Konuma, Masateru Niyada, Chikai Yoshimizu, Eiji Nakayama, Kenro Ishimaru
  • Publication number: 20120139456
    Abstract: When a main switch (12) is turned ON, an electric operating machine (1) is put in the standby mode. With a trigger (13) being pulled in the standby mode, a power supply circuit (16) applies a voltage to a drive part (30). The power supply circuit (16) adjusts the voltage applied to the drive part (30) for a voltage corresponding to the pulling rate of the trigger (13). When the current running toward the drive part (30) exceeds the rated value of the drive part (30), the power supply circuit (16) automatically stops power supply to the drive part (30). On the other hand, when the output voltage of a battery (50) drops and the battery (50) is put in an overdischarge state, power supply to the drive part (30) is automatically stopped. When it is detected that the battery (50) undergoes an abnormal event, power supply to the drive part (30) is automatically stopped.
    Type: Application
    Filed: August 27, 2010
    Publication date: June 7, 2012
    Inventors: Nobuhiro Takano, Kazuhiko Funabashi, Hideyuki Tanimoto, Chikai Yoshimizu, Hiromi Ozawa, Yoshihiro Hoshi
  • Publication number: 20120104881
    Abstract: A motor has an output shaft which is rotatably supported by a housing, a rotor which is fixed to the output shaft and which comprises a printed-wiring board, and a stator which is fixed to the housing and which comprises a magnet facing the rotor. The printed-wiring board comprises a coil/commutator disk and a coil disk. A commutator conductor pattern is formed in a commutator region of the coil/commutator disk. Likewise, coil conductor patterns are formed in respective coil regions of the coil/commutator disk and of the coil disk.
    Type: Application
    Filed: September 22, 2010
    Publication date: May 3, 2012
    Inventors: Hideyuki Tanimoto, Chikai Yoshimizu, Nobuhiro Takano, Hiromi Ozawa, Kazuhiko Funabashi
  • Publication number: 20120104983
    Abstract: An electric grasscutter includes a motor (50) which drives a rotary blade (42). The motor (50) is a brushless motor accommodated in a motor housing (51) and including a rotor (53) provided integrally with an output shaft (52), and a stator (54) fixed to the motor housing (51). A motor control circuit which drives the motor (50) is accommodated in the motor housing (51). The motor control circuit includes an inverter having FETs (81-86) as switching elements, and a control section to control the FETs (81-86). The FETs (81-86) are fixed in contact with the motor housing (51).
    Type: Application
    Filed: September 22, 2010
    Publication date: May 3, 2012
    Inventors: Hideyuki Tanimoto, Chikai Yoshimizu, Nobuhiro Takano, Hiromi Ozawa, Kazuhiko Funabashi
  • Publication number: 20120033405
    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: Application
    Filed: October 19, 2011
    Publication date: February 9, 2012
    Inventors: Katsuhiro OOMORI, Chikai Yoshimizu, Hidekazu Harada, Nobuhiro Takano
  • Publication number: 20110199756
    Abstract: A power tool includes a motor as a drive power source, a body housing the motor and having an end output unit for chucking an end tool, a handle grip connected to the body; and a light unit disposed to one of the handle grip and the body, and having a light-emitting element for providing illumination near the end tool. The light unit includes an angle adjuster and holder which adjusts and holds a lighting angle of the light-emitting element at least in accordance with a length of the end tool.
    Type: Application
    Filed: April 26, 2011
    Publication date: August 18, 2011
    Inventors: Katsuhiro OOMORI, Chikai Yoshimizu, Hidekazu Harada, Nobuhiro Takano
  • Patent number: 7934847
    Abstract: A power tool includes a motor as a drive power source, a body housing the motor and having an end output unit for chucking an end tool, a handle grip connected to the body; and a light unit disposed to one of the handle grip and the body, and having a light-emitting element for providing illumination near the end tool. The light unit comprises switch means for switching the light-emitting element on and off, and an off circuit for automatically turning the light-emitting element off at a predetermined time after the light-emitting element turns on.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: May 3, 2011
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Katsuhiro Oomori, Chikai Yoshimizu, Hidekazu Harada, Nobuhiro Takano
  • Publication number: 20110025255
    Abstract: A solar power system has a charging device. The charging device is powered by a solar cell to charge a battery pack having a secondary cell. The charging device has input voltage detection circuit that detects an input voltage from the solar cell; switching circuit that converts the input voltage to supply a charging current to the battery pack; charging current detection circuit that detects the charging current; and control circuit that controls the switching circuit to change the input voltage in order that a resultant charging current becomes suitable for charging the battery pack.
    Type: Application
    Filed: July 29, 2010
    Publication date: February 3, 2011
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Takao Aradachi, Nobuhiro Takano, Kazuhiko Funabashi, Chikai Yoshimizu, Shigeru Ishikawa, Masanori Aoki