Patents by Inventor Wennong Zhang

Wennong Zhang 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: 8845480
    Abstract: A compound planetary gear mechanism includes at least two planetary gear mechanisms and a carrier. The at least two planetary gear mechanisms include a first planetary gear mechanism and a second planetary gear mechanism. The first planetary gear mechanism includes a plurality of first planetary gears. The second planetary gear mechanism includes a plurality of second planetary gears. The carrier is coupled to the plurality of first planetary gears and the plurality of second planetary gears. The carrier includes a first support shaft and a second support shaft. The first support shaft rotatably supports a first planetary gear among the plurality of first planetary gears. The second support shaft rotatably supports a second planetary gear among the plurality of second planetary gears and is independent of the first support shaft.
    Type: Grant
    Filed: April 30, 2013
    Date of Patent: September 30, 2014
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Wennong Zhang, Hiroshi Nakamura, Yasuo Kishi
  • Publication number: 20130237368
    Abstract: A compound planetary gear mechanism includes at least two planetary gear mechanisms and a carrier. The at least two planetary gear mechanisms include a first planetary gear mechanism and a second planetary gear mechanism. The first planetary gear mechanism includes a plurality of first planetary gears. The second planetary gear mechanism includes a plurality of second planetary gears. The carrier is coupled to the plurality of first planetary gears and the plurality of second planetary gears. The carrier includes a first support shaft and a second support shaft. The first support shaft rotatably supports a first planetary gear among the plurality of first planetary gears. The second support shaft rotatably supports a second planetary gear among the plurality of second planetary gears and is independent of the first support shaft.
    Type: Application
    Filed: April 30, 2013
    Publication date: September 12, 2013
    Applicant: KABUSHIKI KAISHA YASKAWA DENKI
    Inventors: Wennong ZHANG, Hiroshi NAKAMURA, Yasuo KISHI
  • Patent number: 8452453
    Abstract: A robot is provided with: a base section; three motors set on the base section; a support so set that an axial centerline is perpendicular to a surface of the base section; pulleys; three wires into which nonlinear springs are incorporated; an output shaft connected to a load; a differential mechanism having a pinion gear connected to the output shaft and also having an affixation member disposed at the upper end of the support; a universal joint disposed at the ring of the differential mechanism; and a wire guide disposed at the affixation member of the differential mechanism. Two side gears of the differential mechanism and two motors are connected in one-to-one correspondence by means of two wires through the pulleys, and the remaining motor and the universal joint are connected by means of the remaining wire which is passed through the wire guide.
    Type: Grant
    Filed: May 10, 2012
    Date of Patent: May 28, 2013
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Wennong Zhang, Hiroshi Nakamura
  • Patent number: 8274252
    Abstract: A motor control apparatus includes a sub-controller including a two-degree-of-freedom repetitive compensator and a shaping filter. The two-degree-of-freedom repetitive compensator includes a forward delay placed in a forward route of a loop and a feedback delay placed in a feedback route thereof and is configured so that a total delay time provided by the forward delay and the feedback delay is equal to the cycle of a target command or a disturbance. The shaping filter is configured so that the product of the pulse transfer function of the two-degree-of-freedom repetitive compensator and the complementary sensitivity function of a general-purpose control system has a low-pass characteristic.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: September 25, 2012
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Wennong Zhang, Hiroshi Nakamura
  • Publication number: 20120221146
    Abstract: A robot is provided with: a base section; three motors set on the base section; a support so set that an axial centerline is perpendicular to a surface of the base section; pulleys; three wires into which nonlinear springs are incorporated; an output shaft connected to a load; a differential mechanism having a pinion gear connected to the output shaft and also having an affixation member disposed at the upper end of the support; a universal joint disposed at the ring of the differential mechanism; and a wire guide disposed at the affixation member of the differential mechanism. Two side gears of the differential mechanism and two motors are connected in one-to-one correspondence by means of two wires through the pulleys, and the remaining motor and the universal joint are connected by means of the remaining wire which is passed through the wire guide.
    Type: Application
    Filed: May 10, 2012
    Publication date: August 30, 2012
    Applicant: KABUSHIKI KAISHA YASKAWA DENKI
    Inventors: Wennong ZHANG, Hiroshi Nakamura
  • Patent number: 8120302
    Abstract: A servo control apparatus capable of suppressing adverse effects of disturbance, load variation and the like, and realizing robust and high-performance speed control. The apparatus includes both of the following observers: a disturbance observer for adding a disturbance compensation torque Tf, calculated from a torque command T* and an electric motor rotational speed ?m, to a torque command basic signal T0*, calculated on the basis of a deviation between a speed command ?* and a feedback speed ?f by a PI control section, thus outputting the torque command T*; and a phase advance compensation observer for generating, from the torque command basic signal T0* and the electric motor rotational speed ?m, an output of a nominal plant serving as an element in which no delay occurs, thus outputting the output as the feedback speed ?f.
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: February 21, 2012
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Wennong Zhang, Mitsujiro Sawamura, Yasuyuki Takei
  • Patent number: 8115349
    Abstract: A magnetic levitation system includes a levitation-actuator movable element which generates a levitation force applied to a control object; and a levitation-actuator stator which receives a reactive force while the control object is being operated, the levitation-actuator stator being attached to a fixed or movable structure. The levitation-actuator stator includes levitation-actuator stator units connectable to each other in a travelling direction. Each levitation-actuator stator unit includes a coil and an iron core for generating a levitation force between the levitation-actuator stator unit and the levitation-actuator movable element. A length of an end portion of each iron core is equal to or larger than a length of each coil between the ends of the coil so that the cores are continuously arranged without gaps therebetween when the levitation-actuator stator units are connected to each other in the travelling direction.
    Type: Grant
    Filed: January 13, 2010
    Date of Patent: February 14, 2012
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Takashi Mamba, Hiroshi Nakamura, Wennong Zhang
  • Publication number: 20120007541
    Abstract: A motor control apparatus includes a sub-controller including a two-degree-of-freedom repetitive compensator and a shaping filter. The two-degree-of-freedom repetitive compensator includes a forward delay placed in a forward route of a loop and a feedback delay placed in a feedback route thereof and is configured so that a total delay time provided by the forward delay and the feedback delay is equal to the cycle of a target command or a disturbance. The shaping filter is configured so that the product of the pulse transfer function of the two-degree-of-freedom repetitive compensator and the complementary sensitivity function of a general-purpose control system has a low-pass characteristic.
    Type: Application
    Filed: September 23, 2011
    Publication date: January 12, 2012
    Applicant: KABUSHIKI KAISHA YASKAWA DENKI
    Inventors: Wennong ZHANG, Hiroshi Nakamura
  • Patent number: 8040098
    Abstract: A position controller includes a position control part that calculates a speed command on the basis of a difference between a position command and a rotation position of a motor, a PI control part that calculates a torque command on the basis of a speed difference between the speed command and a feedback speed, an observer that generates the feedback speed on the basis of the torque command and a rotation speed of the motor, a phase lead compensator that generates a phase lead compensation signal of the torque command on the basis of the speed command, and an adder that generates a new torque command by adding the phase lead compensation signal of the torque command to the torque command.
    Type: Grant
    Filed: June 11, 2009
    Date of Patent: October 18, 2011
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Wennong Zhang, Shoji Takamatsu, Koji Tomita
  • Patent number: 7725201
    Abstract: In a feedback control apparatus comprising a controller, a control object to be controlled by the controller, and an observer for inputting a control output from the control object and an output of the controller and setting an output of a control object model to be a feedback signal, the observer includes an observer compensator for inputting a difference between the control output and an output of an element model and inputs, to the control object model, a sum of an output of the observer compensator and the output of the controller. Consequently, a control system having an excellent response performance can be constituted and a stable observer can easily be constituted.
    Type: Grant
    Filed: December 13, 2001
    Date of Patent: May 25, 2010
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Wennong Zhang, Yasuhiko Kaku
  • Publication number: 20100109448
    Abstract: A magnetic levitation system includes a levitation-actuator movable element which generates a levitation force applied to a control object; and a levitation-actuator stator which receives a reactive force while the control object is being operated, the levitation-actuator stator being attached to a fixed or movable structure. The levitation-actuator stator includes levitation-actuator stator units connectable to each other in a travelling direction. Each levitation-actuator stator unit includes a coil and an iron core for generating a levitation force between the levitation-actuator stator unit and the levitation-actuator movable element. A length of an end portion of each iron core is equal to or larger than a length of each coil between the ends of the coil so that the cores are continuously arranged without gaps therebetween when the levitation-actuator stator units are connected to each other in the travelling direction.
    Type: Application
    Filed: January 13, 2010
    Publication date: May 6, 2010
    Applicant: KABUSHIKI KAISHA YASKAWA DENKI
    Inventors: Takashi MAMBA, Hiroshi Nakamura, Wennong Zhang
  • Publication number: 20090251092
    Abstract: A position controller includes a position control part that calculates a speed command on the basis of a difference between a position command and a rotation position of a motor, a PI control part that calculates a torque command on the basis of a speed difference between the speed command and a feedback speed, an observer that generates the feedback speed on the basis of the torque command and a rotation speed of the motor, a phase lead compensator that generates a phase lead compensation signal of the torque command on the basis of the speed command, and an adder that generates a new torque command by adding the phase lead compensation signal of the torque command to the torque command.
    Type: Application
    Filed: June 11, 2009
    Publication date: October 8, 2009
    Applicant: KABUSHIKI KAISHA YASKAWA DENKI
    Inventors: Wennong ZHANG, Shoji TAKAMATSU, Koji TOMITA
  • Publication number: 20090243533
    Abstract: The present invention provides a servo control apparatus capable of suppressing adverse effects of disturbance, load variation and the like, and realizing robust and high-performance speed control. The apparatus includes both of the following observers: a disturbance observer (5) for adding a disturbance compensation torque Tf, calculated from a torque command T* and an electric motor rotational speed ?m, to a torque command basic signal T0*, calculated on the basis of a deviation between a speed command ?* and a feedback speed ?f by a PI control section (2), thus outputting the torque command T*; and a phase advance compensation observer (6) for generating, from the torque command basic signal T0* and the electric motor rotational speed ?m, an output of a nominal plant (61) serving as an element in which no delay occurs, thus outputting the output as the feedback speed ?f.
    Type: Application
    Filed: January 23, 2007
    Publication date: October 1, 2009
    Applicant: KABUSHIKI KAISHA YASKAWA DENKI
    Inventors: Wennong Zhang, Mitsujiro Sawamura, Yasuyuki Takei
  • Patent number: 7345443
    Abstract: It is an object of the invention to provide a motor control apparatus capable of ensuring a control function even for a large inertia moment ratio.
    Type: Grant
    Filed: March 24, 2005
    Date of Patent: March 18, 2008
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Yasufumi Yoshiura, Yasuhiko Kaku, Keisei Inoki, Wennong Zhang
  • Publication number: 20070210731
    Abstract: It is an object of the invention to provide a motor control apparatus capable of ensuring a control function even for a large inertia moment ratio.
    Type: Application
    Filed: March 24, 2005
    Publication date: September 13, 2007
    Inventors: Yasufumi Yoshiura, Yasuhiko Kaku, Keisei Inoki, Wennong Zhang
  • Patent number: 7164953
    Abstract: In a speed control system, there are provided a speed observer compensator (10) for inputting a difference between a speed VM of a mechanical system (5) and an estimated value VMO of a speed of the mechanical system (5) which is obtained by a speed observer (6) and outputting a speed difference VM?VMO based on the input, and a mechanical system model (8) for inputting a sum of an output of the speed observer compensator (10) and an output Tro of a PI controller (2), and the speed observer (6) is constituted in such a manner that the signal VMO produced after a passage of an output of the mechanical system model (8) through a filter delay element model (11) and a dead time delay element model (12) is equal to the speed VM of the mechanical system (5), and the output of the mechanical system model (8) is set to be a speed feedback signal Vf of the speed control system.
    Type: Grant
    Filed: July 18, 2002
    Date of Patent: January 16, 2007
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Wennong Zhang, Yasuhiko Kaku
  • Patent number: 6828749
    Abstract: A full-closed control apparatus for performing velocity control based on a velocity signal of a motor and performing position control based on a position signal of a load driven by the motor, including: an equivalent rigid system velocity loop model; a band-pass filter; an amplitude adjuster; and a unit for inputting a velocity instruction of a velocity control loop into the equivalent rigid system velocity loop model, inputting a difference signal obtained by subtracting an output of the equivalent rigid system velocity loop model from a velocity signal of the load into the band-pass filter, inputting an output of the band-pass filter into the amplitude adjuster and outputting a signal obtained by adding an output of the amplitude adjuster to an output of a position controller, as a new velocity instruction.
    Type: Grant
    Filed: August 22, 2003
    Date of Patent: December 7, 2004
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Wennong Zhang, Yasuhiko Kaku
  • Publication number: 20040239280
    Abstract: In a speed control system, there are provided a speed observer compensator (10) for inputting a difference between a speed VM of a mechanical system (5) and an estimated value VMO of a speed of the mechanical system (5) which is obtained by a speed observer (6) and outputting a speed difference VM−VMO based on the input, and a mechanical system model (8) for inputting a sum of an output of the speed observer compensator (10) and an output Tro of a PI controller (2), and the speed observer (6) is constituted in such a manner that the signal VMO produced after a passage of an output of the mechanical system model (8) through a filter delay element model (11) and a dead time delay element model (12) is equal to the speed VM of the mechanical system (5), and the output of the mechanical system model (8) is set to be a speed feedback signal Vf of the speed control system.
    Type: Application
    Filed: July 6, 2004
    Publication date: December 2, 2004
    Inventors: Wennong Zhang, Yasuhiko Kaku
  • Patent number: 6801010
    Abstract: To provide a vibration-damping positioning controller capable of effecting stable positioning operation within a short period of time.
    Type: Grant
    Filed: August 5, 2003
    Date of Patent: October 5, 2004
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Wennong Zhang, Yasuhiko Kaku, Tadashi Okubo
  • Publication number: 20040113579
    Abstract: A full-closed control apparatus for performing velocity control based on a velocity signal of a motor and performing position control based on a position signal of a load driven by the motor, including: an equivalent rigid system velocity loop model; a band-pass filter; an amplitude adjuster; and a unit for inputting a velocity instruction of a velocity control loop into the equivalent rigid system velocity loop model, inputting a difference signal obtained by subtracting an output of the equivalent rigid system velocity loop model from a velocity signal of the load into the band-pass filter, inputting an output of the band-pass filter into the amplitude adjuster and outputting a signal obtained by adding an output of the amplitude adjuster to an output of a position controller, as a new velocity instruction.
    Type: Application
    Filed: August 22, 2003
    Publication date: June 17, 2004
    Applicant: KABUSHIKI KAISHA YASKAWA DENKI
    Inventors: Wennong Zhang, Yasuhiko Kaku