Patents by Inventor Koji Akamatsu

Koji Akamatsu 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: 6469522
    Abstract: An electrical discharge state detecting device for an electrical discharge machining machine which detects an electrical discharge state during an electrical discharge machining operation. The detecting device includes a high-pass filter for detecting a high-frequency component superimposed on an electrical discharge voltage or an electrical discharge current at a machining clearance between an electrode and a workpiece, a rectifying circuit for outputting a rectified component of the high-frequency component, a first integration circuit for integrating the rectified component, a reference voltage circuit, a second integrating circuit for integrating the reference voltage, a comparator for comparing the two integrated values, an electrical discharge generation detecting circuit for controlling starting and ending of the integrating circuits, a logic circuit, and a delay circuit and reset circuits.
    Type: Grant
    Filed: January 23, 2001
    Date of Patent: October 22, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Koji Akamatsu
  • Patent number: 6359448
    Abstract: An electrical discharge state detecting device for an electrical discharge machining machine which detects an electrical discharge state during an electrical discharge machining operation. The detecting device includes a high-pass filter for detecting a high-frequency component superimposed on an electrical discharge voltage or an electrical discharge current at a machining clearance between an electrode and a workpiece, a rectifying circuit for outputting a rectified component of the high-frequency component, a first integration circuit for integrating the rectified component, a reference voltage circuit, a second integrating circuit for integrating the reference voltage, a comparator for comparing the two integrated values, an electrical discharge generation detecting circuit for controlling starting and ending of the integrating circuits, a logic circuit, and a delay circuit and reset circuits.
    Type: Grant
    Filed: January 23, 2001
    Date of Patent: March 19, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Koji Akamatsu
  • Publication number: 20010003425
    Abstract: An electrical discharge state detecting device for an electrical discharge machining machine which detects an electrical discharge state during an electrical discharge machining operation. The detecting device includes a high-pass filter for detecting a high-frequency component superimposed on an electrical discharge voltage or an electrical discharge current at a machining clearance between an electrode and a workpiece, a rectifying circuit for outputting a rectified component of the high-frequency component, a first integration circuit for integrating the rectified component, a reference voltage circuit, a second integrating circuit for integrating the reference voltage, a comparator for comparing the two integrated values, an electrical discharge generation detecting circuit for controlling starting and ending of the integrating circuits, a logic circuit, and a delay circuit and reset circuits.
    Type: Application
    Filed: January 23, 2001
    Publication date: June 14, 2001
    Inventor: Koji Akamatsu
  • Publication number: 20010002104
    Abstract: An electrical discharge state detecting device for an electrical discharge machining machine which detects an electrical discharge state during an electrical discharge machining operation. The detecting device includes a high-pass filter for detecting a high-frequency component superimposed on an electrical discharge voltage or an electrical discharge current at a machining clearance between an electrode and a workpiece, a rectifying circuit for outputting a rectified component of the high-frequency component, a first integration circuit for integrating the rectified component, a reference voltage circuit, a second integrating circuit for integrating the reference voltage, a comparator for comparing the two integrated values, an electrical discharge generation detecting circuit for controlling starting and ending of the integrating circuits, a logic circuit, and a delay circuit and reset circuits.
    Type: Application
    Filed: January 23, 2001
    Publication date: May 31, 2001
    Inventor: Koji Akamatsu
  • Patent number: 6208150
    Abstract: An electrical discharge state detecting device for an electrical discharge machining machine which detects an electrical discharge state during an electrical discharge machining operation. The detecting device includes a high-pass filter for detecting a high-frequency component superimposed on an electrical discharge voltage or an electrical discharge current at a machining clearance between an electrode and a workpiece, a rectifying circuit for outputting a rectified component of the high-frequency component, a first integration circuit for integrating the rectified component, a reference voltage circuit, a second integrating circuit for integrating the reference voltage, a comparator for comparing the two integrated values, an electrical discharge generation detecting circuit for controlling starting and ending of the integrating circuits, a logic circuit, and a delay circuit and reset circuits.
    Type: Grant
    Filed: May 5, 1998
    Date of Patent: March 27, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Koji Akamatsu
  • Patent number: 5801352
    Abstract: A power supply unit for a discharge machining apparatus which eliminates overshooting in current rise and improves the electrode consumption characteristics by preventing an operational amplifier as well as a current control element from being saturated, thereby eliminating overshooting during the rise time of the machining current, by clamping the output voltage of the operational amplifier during the stand-by time for electric discharge. The output is clamped by a plurality of resistors and diodes to a state where the output voltage is higher than a power-supply voltage (the output clamp level is set by a resistor). Namely, during the stand-by time when inverted amplification (feedback) via a resistor in an operational amplifier is being carried out, a constant state of feedback is maintained by the diodes.
    Type: Grant
    Filed: September 8, 1995
    Date of Patent: September 1, 1998
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Mitsubishi Electric Engineering Co., Ltd.
    Inventors: Atsushi Taneda, Koji Akamatsu, Hajime Ogawa, Satoshi Suzuki
  • Patent number: 5751155
    Abstract: An electrical discharge state detecting device for an electrical discharge machining machine which detects an electrical discharge state during an electrical discharge machining operation. The detecting device includes a high-pass filter for detecting a high-frequency component superimposed on an electrical discharge voltage or an electrical discharge current at a machining clearance between an electrode and a workpiece, a rectifying circuit for outputting a rectified component of the high-frequency component, a first integration circuit for integrating the rectified component, a reference voltage circuit, a second integrating circuit for integrating the reference voltage, a comparator for comparing the two integrated values, an electrical discharge generation detecting circuit for controlling starting and ending of the integrating circuits, a logic circuit, and a delay circuit and reset circuits.
    Type: Grant
    Filed: August 3, 1995
    Date of Patent: May 12, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Koji Akamatsu
  • Patent number: 5383026
    Abstract: The invention permits determination of the position and/or the configuration of an object by impinging a laser light beam onto the object in a light scattering medium, and detecting the trace of a scattered light beam, by cameras.
    Type: Grant
    Filed: April 23, 1992
    Date of Patent: January 17, 1995
    Assignees: Naotake Mouri, Mitsubishi Denki Kabushiki Kaisha
    Inventors: Naotake Mouri, Koji Akamatsu, Akihiro Goto
  • Patent number: 5200905
    Abstract: An electric discharge machining control apparatus in which the know how of a skilled person can be readily written which concerns the setting of machining conditions such as pause time, discharge duration time, servo reference voltage, and speed gain which are necessary for maintaining optimum electric discharge machining conditions and for offering a maximum electric discharge machining efficiency, as well as the criterions to the instability of electric discharge machining conditions. According to the know how, the machining control is carried out in a most suitable manner, and can be automatically adjusted when required.
    Type: Grant
    Filed: August 7, 1990
    Date of Patent: April 6, 1993
    Assignee: Mitsubishi Denki K.K.
    Inventors: Kazuhiko Uemoto, Koji Akamatsu, Nobuaki Ohba
  • Patent number: 5047703
    Abstract: The present invention relates to a motor driving device wherein two motors are held in engagement with an identical spindle through respective torque transmission mechanisms, and wherein each of the motors has a driving amplifier for generating a torque in a direction reverse to that of a torque of the other motor; comprising an integration circuit which integrates with respect to time a difference signal between an angle command value of the spindle and a rotational angle feedback value thereof, and which applies its integral output to the driving amplifiers in common.
    Type: Grant
    Filed: October 25, 1989
    Date of Patent: September 10, 1991
    Inventor: Koji Akamatsu