Patents by Inventor Yoshio Iimura

Yoshio Iimura 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: 20180199506
    Abstract: “A self-propelled grass mower and a self-propelled wheeled apparatus that can perform precise guidance control by reliably detecting a guidance signal with a guidewire are provided. The self-propelled grass mower includes wheel motors for driving wheels, a cutting blade motor for driving a cutting blade, a rechargeable battery for supplying electrical power to these motors, and a guidewire sensor for detecting a magnetic field generated by a guidewire formed into a loop. In the self-propelled grass mower that detects whether is inside or outside of a region enclosed by the guidewire and runs autonomously in a grass cutting region, only the supply voltage for the cutting blade motor is reduced when a magnetic field is detected by the guidewire sensor. Driving of the cutting blade motor is restarted after detection of the magnetic field has completed. Thereby, the impact of noise due to the cutting blade motor is eliminated.
    Type: Application
    Filed: August 26, 2016
    Publication date: July 19, 2018
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Tatsuya ITO, Yoshio IIMURA
  • Patent number: 9833890
    Abstract: An electric tool including: a motor configured to drive a front end tool; a control device configure to control rotation of the motor; a storage part configured to store a method of driving the motor by the control device; and a communication terminal to which a communication line for reading or writing information of the storage part is configured to be connected.
    Type: Grant
    Filed: May 18, 2012
    Date of Patent: December 5, 2017
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Tatsuya Ito, Tomomasa Nishikawa, Hironori Mashiko, Mizuho Nakamura, Yoshio Iimura
  • Patent number: 9473055
    Abstract: An electric working machine including: an input part; a control unit configured to control a motor in accordance with an operation amount of the input part; and a switching part; wherein, when a predetermined operation is performed to the switching part, the control unit shifts to a fixed control mode in which the motor is controlled in accordance with an operation amount of the input part at the time when the predetermined operation is performed to the switching part, irrespective of an operation amount of the input part after the predetermined operation is performed to the switching part.
    Type: Grant
    Filed: August 15, 2013
    Date of Patent: October 18, 2016
    Assignee: HITACHI KOKI CO., LTD.
    Inventors: Tatsuya Ito, Mizuho Nakamura, Yoshio Iimura, Tomomasa Nishikawa
  • Publication number: 20150022125
    Abstract: An electric tool for driving a tip tool, the electric tool includes: a removable battery; the brushless motor configured to generate a driving force for driving the tip tool; an inverter circuit configured to supply drive power from the removable battery to the brushless motor using a plurality of semiconductor switching elements; a controller configured to control the inverter circuit to control rotation of the brushless motor; a temperature detector configured to detect a temperature of the brushless motor or the semiconductor switching elements; and a voltage detector configured to detect a voltage of the battery. The brushless motor is driven such that a duty ratio of PWM drive signal for driving the semiconductor switching elements is determined based on relationship between the temperature detected by the temperature detector and the voltage detected by the voltage detector.
    Type: Application
    Filed: March 13, 2013
    Publication date: January 22, 2015
    Inventors: Nobuhiro Takano, Tetsuhiro Harada, Yoshio Iimura, Tomomasa Nishikawa, Hiroki Uchida, Yoshihiro Nakano
  • Publication number: 20140049204
    Abstract: An electric working machine including: an input part; a control unit configured to control a motor in accordance with an operation amount of the input part; and a switching part; wherein, when a predetermined operation is performed to the switching part, the control unit shifts to a fixed control mode in which the motor is controlled in accordance with an operation amount of the input part at the time when the predetermined operation is performed to the switching part, irrespective of an operation amount of the input part after the predetermined operation is performed to the switching part.
    Type: Application
    Filed: August 15, 2013
    Publication date: February 20, 2014
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Tatsuya Ito, Mizuho Nakamura, Yoshio Iimura, Tomomasa Nishikawa
  • Patent number: 8607892
    Abstract: According to an aspect of the present invention, there is provided a rotary striking tool includes: a motor; an oil pulse unit that is driven by the motor; an output shaft that is coupled to the oil pulse unit so that a tip tool can be attached to the output shaft; a first detection unit that detects a rotation angle of the motor and outputs a first output signal; a second detection unit that detects an impact generated at the oil pulse unit and outputs a second output signal; and a control unit that controls a rotation of the motor, wherein the control unit uses a portion of the second output signal based on the first output signal for control of the rotation of the motor.
    Type: Grant
    Filed: September 8, 2010
    Date of Patent: December 17, 2013
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshio Iimura, Kenro Ishimaru, Kazutaka Iwata, Nobuhiro Takano
  • Publication number: 20130245789
    Abstract: An electric tool includes a motor, a light having a function in addition to a data transmission, a switch configured to switch power supply to the light in accordance with a user operation; and a control unit. Upon a switch is switched from OFF to ON, the light is blinked at a frequency above the human-sensible range on the basis of data such as the usage history data of the electric tool. An average of the blinking frequency of the light is approximately 4,800 Hz when a bit rate is set to 9,600 bps, for example. Further, an average of a duty ratio of a drive signal of the light during blinking is approximately 50%.
    Type: Application
    Filed: February 6, 2013
    Publication date: September 19, 2013
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Yoshio Iimura, Hironori Mashiko, Tomomasa Nishikawa, Tatsuya Ito
  • Patent number: 8360166
    Abstract: According to an aspect of the present invention, there is provided a rotary striking tool, including: a motor; an impact unit having a driving part being driven by the motor and an output part; a tip-tool side output shaft that is coupled to the output part; an impact detection unit that detects an impact generated at the impact unit; and a control unit programmed to: control the impact unit to perform a confirmation striking when the impact detected by the impact detection unit reaches a prescribed value, detect a rotation angle of the output shaft at the confirmation striking, determine whether a fastening operation is completed when the detected rotation angle is equal to or smaller than a predetermined angle, and continue the fastening operation when the detected rotation angle is larger than the predetermined angle.
    Type: Grant
    Filed: September 8, 2010
    Date of Patent: January 29, 2013
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshio Iimura, Kenro Ishimaru, Kazutaka Iwata, Nobuhiro Takano
  • Patent number: 8328524
    Abstract: An air compressor includes: a tank portion for reserving compressed air used in a pneumatic tool; a compressed air generation portion for generating compressed air and supplying the compressed air to the tank portion; a drive portion including a motor for driving the compressed air generation portion; a control circuit portion for controlling the drive portion; and a pressure sensor for detecting pressure of the compressed air reserved in the tank portion. The control circuit portion includes a unit for controlling the rotational speed of the motor multistageously based on a detection signal output from the pressure sensor.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: December 11, 2012
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshio Iimura, Hiroaki Orikasa, Mitsuhiro Sunaoshi, Toshiaki Uchida, Kazuhiro Segawa
  • Publication number: 20120292070
    Abstract: An electric tool including: a motor configured to drive a front end tool; a control device configure to control rotation of the motor; a storage part configured to store a method of driving the motor by the control device; and a communication terminal to which a communication line for reading or writing information of the storage part is configured to be connected.
    Type: Application
    Filed: May 18, 2012
    Publication date: November 22, 2012
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Tatsuya ITO, Tomomasa NISHIKAWA, Hironori MASHIKO, Mizuho NAKAMURA, Yoshio IIMURA
  • Publication number: 20110079407
    Abstract: According to an aspect of the present invention, there is provided a rotary striking tool, including: a motor; an impact unit having a driving part being driven by the motor and an output part; a tip-tool side output shaft that is coupled to the output part; an impact detection unit that detects an impact generated at the impact unit; and a control unit programmed to: control the impact unit to perform a confirmation striking when the impact detected by the impact detection unit reaches a prescribed value, detect a rotation angle of the output shaft at the confirmation striking, determine whether a fastening operation is completed when the detected rotation angle is equal to or smaller than a predetermined angle, and continue the fastening operation when the detected rotation angle is larger than the predetermined angle.
    Type: Application
    Filed: September 8, 2010
    Publication date: April 7, 2011
    Inventors: Yoshio Iimura, Kenro Ishimaru, Kazutaka Iwata, Nobuhiro Takano
  • Publication number: 20110073334
    Abstract: According to an aspect of the present invention, there is provided a rotary striking tool includes: a motor; an oil pulse unit that is driven by the motor; an output shaft that is coupled to the oil pulse unit so that a tip tool can be attached to the output shaft; a first detection unit that detects a rotation angle of the motor and outputs a first output signal; a second detection unit that detects an impact generated at the oil pulse unit and outputs a second output signal; and a control unit that controls a rotation of the motor, wherein the control unit uses a portion of the second output signal based on the first output signal for control of the rotation of the motor.
    Type: Application
    Filed: September 8, 2010
    Publication date: March 31, 2011
    Inventors: Yoshio Iimura, Kenro Ishimaru, Kazutaka Iwata, Nobuhiro Takano
  • Patent number: 7704052
    Abstract: An air compressor includes: a tank portion for reserving compressed air used in a pneumatic tool; a compressed air generation portion for generating compressed air and supplying the compressed air to the tank portion; a drive portion including a motor for driving the compressed air generation portion; a control circuit portion for controlling the drive portion; and a pressure sensor for detecting pressure of the compressed air reserved in the tank portion. The control circuit portion includes a unit for controlling the rotational speed of the motor multistageously on the basis of a detection signal output from the pressure sensor.
    Type: Grant
    Filed: February 19, 2004
    Date of Patent: April 27, 2010
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshio Iimura, Hiroaki Orikasa, Mitsuhiro Sunaoshi, Toshiaki Uchida, Kazuhiro Segawa
  • Patent number: 7641449
    Abstract: For a motor that drives a compressed air generator, three operating modes which includes a powerful mode for rotating a motor in a high speed range, a silent mode for rotating the motor in a low speed range, and an automatic mode for automatically changing the rotation speed of the motor from the low speed to the high speed in accordance with a setup condition are prepared. A user can designate a desired operating mode by using an operating mode selection switch.
    Type: Grant
    Filed: June 23, 2004
    Date of Patent: January 5, 2010
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshio Iimura, Hiroaki Orikasa, Mitsuhiro Sunaoshi, Kazuhiro Segawa
  • Publication number: 20090288849
    Abstract: An air compressor includes: a tank portion for reserving compressed air used in a pneumatic tool; a compressed air generation portion for generating compressed air and supplying the compressed air to the tank portion; a drive portion including a motor for driving the compressed air generation portion; a control circuit portion for controlling the drive portion; and a pressure sensor for detecting pressure of the compressed air reserved in the tank portion. The control circuit portion includes a unit for controlling the rotational speed of the motor multistageously based on a detection signal output from the pressure sensor.
    Type: Application
    Filed: July 30, 2009
    Publication date: November 26, 2009
    Applicant: HITACHI KOKI CO., LTD.
    Inventors: Yoshio Iimura, Hiroaki Orikasa, Mitsuhiro Sunaoshi, Toshiaki Uchida, Kazuhiro Segawa
  • Patent number: 7476088
    Abstract: A control circuit portion in an air compressor finds the rate of decrease of pressure inside a tank portion when a motor is at rest relative to the time based on a detection signal from a pressure sensor. Where the rate of decrease of pressure is greater than a given value, the motor is started without waiting for the pressure inside the tank to decrease to a motor restart pressure value, the pressure inside the tank portion rises to a given motor stop pressure value and the motor is then controlled to come to a stop. Where the rate of decrease of pressure is less than the given value, the motor is started when the pressure inside the tank has decreased to the motor restart pressure value. After the start of the motor, the motor is controlled such that it comes to a stop when the pressure inside the tank portion increases to a given value lower than the motor stop pressure value.
    Type: Grant
    Filed: October 26, 2005
    Date of Patent: January 13, 2009
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshio Iimura, Hiroaki Orikasa
  • Patent number: 7326038
    Abstract: An air compressor comprises a tank portion for reserving a compressed air, a compressed air generating portion for generating the compressed air to be supplied to the tank portion, a motor for driving the compressed air generating portion, and a pressure switch mechanism having a pressure sensor in a part of the tank portion, and controlling the motor to be turned on or off in accordance with an output of the pressure sensor, characterized in that when the time change rate of the pressure within air tank is greater than a predetermined value, the motor is restarted without waiting until the pressure decreases to the switch on point at the time of pressure fall.
    Type: Grant
    Filed: June 23, 2004
    Date of Patent: February 5, 2008
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshio Iimura, Hiroaki Orikasa, Mitsuhiro Sunaoshi, Kazuhiro Segawa
  • Publication number: 20060110258
    Abstract: A control circuit portion in an air compressor finds the rate of decrease of pressure inside a tank portion when a motor is at rest relative to the time based on a detection signal from a pressure sensor. Where the rate of decrease of pressure is greater than a given value, the motor is started without waiting for the pressure inside the tank to decrease to a motor restart pressure value, the pressure inside the tank portion rises to a given motor stop pressure value and the motor is then controlled to come to a stop. Where the rate of decrease of pressure is less than the given value, the motor is started when the pressure inside the tank has decreased to the motor restart pressure value. After the start of the motor, the motor is controlled such that it comes to a stop when the pressure inside the tank portion increases to a given value lower than the motor stop pressure value.
    Type: Application
    Filed: October 26, 2005
    Publication date: May 25, 2006
    Inventors: Yoshio Iimura, Hiroaki Orikasa
  • Patent number: 7017342
    Abstract: An air compressor includes a tank unit storing a compressed air used by a pneumatic tool, a compressed air generator which generates the compressed air and supplies the compressed air to the tank unit, a motor driving the compressed air generator, a drive portion including the motor, a controller portion controlling the drive portion and a pressure sensor detecting an air pressure of the compressed air in the tank unit, in which the controller portion controls a rotation speed of the motor at multiple levels based on a detection signal P1 of the pressure sensor, a first differential signal which is a differential value d(P1)/dt of the detection signal P1, and a second differential signal which is a differential value d(P2)/dt of a detection signal P2 obtained by removing a pulsatory element from the detection signal P1.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: March 28, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshio Iimura, Hiroaki Orikasa, Mitsuhiro Sunaoshi, Kazuhiro Segawa
  • Publication number: 20050053483
    Abstract: An air compressor includes a tank unit storing a compressed air used by a pneumatic tool, a compressed air generator which generates the compressed air and supplies the compressed air to the tank unit, a motor driving the compressed air generator, a drive portion including the motor, a controller portion controlling the drive portion and a pressure sensor detecting an air pressure of the compressed air in the tank unit, in which the controller portion controls a rotation speed of the motor at multiple levels based on a detection signal P1 of the pressure sensor, a first differential signal which is a differential value d(P1)/dt of the detection signal P1, and a second differential signal which is a differential value d(P2)/dt of a detection signal P2 obtained by removing a pulsatory element from the detection signal P1.
    Type: Application
    Filed: July 29, 2004
    Publication date: March 10, 2005
    Applicant: Hitachi Koki Co., Ltd.
    Inventors: Yoshio Iimura, Hiroaki Orikasa, Mitsuhiro Sunaoshi, Kazuhiro Segawa