Plural, Diverse Conditions Patents (Class 318/639)
  • Patent number: 9158256
    Abstract: An image forming apparatus includes: rotators; a drive motor configured to drive the plurality of rotators and including a hall element configured to output a hall signal according to a change of a magnetic field; a counter configured to count the hall signal; an image forming unit forming a color image on a recording medium; and a controller configured to function as: an acquiring unit controlling the image forming unit to form a test pattern on the recording medium, and acquiring correction information based on the formed test pattern; a phase managing unit managing the phases of the rotators based on a count value of the counter from the formation start timing; and a correcting unit correcting the positional deviation based on the phases which are managed by the phase managing unit, and the correction information acquired by the acquiring unit.
    Type: Grant
    Filed: May 30, 2013
    Date of Patent: October 13, 2015
    Assignee: BROTHER KOGYO KABUSHIKI KAISHA
    Inventor: Osamu Takahashi
  • Publication number: 20140354209
    Abstract: A machine tool according to an embodiment includes a drive mechanism configured to move a control target; a motor configured to operate the drive mechanism; a first encoder configured to detect a position of the control target; a second encoder configured to detect a position of the motor; a servo control unit configured to control the motor; and a numerical control unit configured to receive or calculate an error between the position of the control target obtained from a detection result of the first encoder and a position of the control target obtained from a detection result of the second encoder from the servo control unit, and to estimate a transmission error of the drive mechanism based on a change amount of the error between before and after inversion of a moving direction of the control target.
    Type: Application
    Filed: May 29, 2014
    Publication date: December 4, 2014
    Applicant: Toshiba Kikai Kabushiki Kaisha
    Inventors: Jun FUJITA, Chihiro SAGA
  • Patent number: 8897930
    Abstract: This application describes the software invented to control an electric motor system. The electric motor system is mounted on one or more aircraft main wheels or nose wheels to drive an aircraft independently on the ground without aircraft engines or tow vehicles. The software uses closed-loop control together with several other control laws to operate the drive motor or motors. Knowledge of the current operating state of the drive motor, together with knowledge of the commands given to taxi forward, taxi in reverse, or brake in reverse, is used to configure the motors to optimal operating parameters. The software architecture is described along with the pilot interface and many details of software implementation.
    Type: Grant
    Filed: July 27, 2011
    Date of Patent: November 25, 2014
    Inventor: Janice Ilene Bayer
  • Publication number: 20140132195
    Abstract: Disclosed herein are an apparatus and method for control of an electric booster. The apparatus includes a sensing unit to sense information about at least one of displacement and velocity variation of a ball screw, a control unit to receive the information, the control unit including a preset range of reference Wall Pattern position and reference Wall Pattern velocity, a determination unit to determine whether the information is within at least one of the range of reference Wall Pattern position and the range of reference Wall Pattern velocity, and a ball screw initial position setting unit to set a current position of the ball screw contacting a rear wall of the master cylinder to an initial position of the ball screw when it is determined that the information is within the range of reference Wall Pattern position and the range of reference Wall Pattern velocity.
    Type: Application
    Filed: November 12, 2013
    Publication date: May 15, 2014
    Applicant: MANDO CORPORATION
    Inventor: Kyuwoong CHOI
  • Patent number: 8670904
    Abstract: A motor control device includes: a rotation angle detection portion that detects a rotation angle of a motor and outputs a rotation angle signal; an abnormal condition detection portion that detects the presence or absence of an abnormal condition of the rotation angle detection portion; a rotation angle estimation portion that estimates the rotation angle of the motor and outputs an estimate rotation angle signal; and a driving control portion that controls driving of the motor on the basis of the rotation angle signal, which is output from the rotation angle detection portion, when the abnormal condition detection portion does not detect an abnormal condition of the rotation angle detection portion, and controls driving of the motor on the basis of the estimate rotation angle signal, which is output from the rotation angle estimation portion, when the abnormal condition detection portion detects an abnormal condition of the rotation angle detection portion.
    Type: Grant
    Filed: May 28, 2009
    Date of Patent: March 11, 2014
    Assignee: Honda Motor Co., Ltd.
    Inventors: Atsuhiko Yoneda, Yasuo Shimizu
  • Publication number: 20130234643
    Abstract: An acceleration command calculator 22 calculates an acceleration command “as” based on an output torque Tmb of the spindle motor applied when the rotational speed is less than or equal to a base rotational speed and an inertia Jm+Jl of the overall spindle. A switching speed calculator 23 calculates a control mode switching speed Vs based on the acceleration command “as”. A control mode switching switch 5 switches from a speed control mode to a position control mode when the motor speed Vm becomes less than or equal to the control mode switching speed Vs, to stop the spindle at a desired rotational position. The control mode switching speed Vs may be a value calculated using the following equation: Vs=60×(amax×0.5)1/2, where a maximum acceleration that can be achieved at this time is represented by a max.
    Type: Application
    Filed: March 4, 2013
    Publication date: September 12, 2013
    Applicant: OKUMA CORPORATION
    Inventors: Tomohiro Shibata, Tomohisa Kameyama
  • Patent number: 8525465
    Abstract: A feedback switching device and a method allow a drive control loop for a servo motor to actively switch the feedback mode in accordance with the rotating speed of the servo motor. When the servo motor is under a high speed operation, a sensorless position estimation feedback technology is used as the feedback mode; on the other hand, when the servo motor is under a low speed operation, the switching mode is automatically switched to a position sensing feedback technology. Therefore, the development needs for multi-function, high performance and low cost in the field of the servo motor control are met, and the conventional problem is solved that, when being applied to a servo driving system having a wide speed range, the single use of the position sensing feedback technology or the sensorless position estimation feedback technology fails to satisfy the application for a wide speed range.
    Type: Grant
    Filed: December 9, 2010
    Date of Patent: September 3, 2013
    Assignee: Industrial Technology Research Institute
    Inventors: Kuo-Lin Chiu, Chia-Min Ting, Hsin-Hung Chou
  • Patent number: 8344675
    Abstract: A rechargeable electric power tool includes a motor driven by a secondary battery, a switching element for regulating power distribution to the motor, a motor control unit for controlling rotation of the motor through the switching element, a lead wire for supplying a drive current to the motor therethrough and a trigger switch changed over by a user for turning on or off the drive current supplied to the motor through the lead wire. In the rechargeable electric power tool, upon changeover of the trigger switch, a microcomputer determines a magnitude relation between a detected temperature outputted from a first thermistor and a first temperature threshold value. If the detected temperature is determined to be greater than the first temperature threshold value, the microcomputer is set in a limited operation mode in which a revolution number of the motor is limited to a predetermined value or less.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: January 1, 2013
    Assignee: Panasonic Electric Works Power Tools Co., Ltd
    Inventors: Tatsuya Miwa, Atsumasa Kubota, Masaki Ikeda, Kazuhiko Nishii
  • Patent number: 8299743
    Abstract: A machine tool a tool includes a supporting member relatively movable to a workpiece along a predetermined axis, a servo motor configured to drive the tool supporting member to the workpiece along the predetermined axis, a sizing sensor configured to measure a profile of the workpiece and to output a size deviation of measured values from a target profile, and a position detector configured to detect at least one of a relative position of the tool supporting member to the workpiece and a rotational position angle of the servo motor. The a servo driver is configured to drive the servo motor, and has a first feedback control having an output based on the size deviation, and a second feedback control based on an output of the position detector. The servo drives the servo motor by combining the outputs of the first and second feedback controls.
    Type: Grant
    Filed: January 12, 2010
    Date of Patent: October 30, 2012
    Assignee: JTEKT Corporation
    Inventors: Satoshi Abeta, Toshihiro Yonezu
  • Publication number: 20120238796
    Abstract: A device for manipulating a magnetic coupling force across tissue in response to a monitored coupling force is described. The device includes a magnetic field source assembly, a positioning assembly operatively connected to the magnetic field force assembly, and a magnetic coupling force monitor. The magnetic field source assembly includes magnets that provide an external magnetic field source for providing a magnetic field across tissue. The positioning assembly adjusts the position of the magnetic field source. The magnetic field creates a magnetic coupling force between the external magnetic field source and an object positioned in use in a patient during a procedure, wherein the object has or is associated with an internal magnetic field.
    Type: Application
    Filed: March 15, 2012
    Publication date: September 20, 2012
    Applicant: Ethicon Endo-Surgery, Inc.
    Inventor: Sean P. Conlon
  • Publication number: 20120098476
    Abstract: A feedback switching device and a method allow a drive control loop for a servo motor to actively switch the feedback mode in accordance with the rotating speed of the servo motor. When the servo motor is under a high speed operation, a sensorless position estimation feedback technology is used as the feedback mode; on the other hand, when the servo motor is under a low speed operation, the switching mode is automatically switched to a position sensing feedback technology. Therefore, the development needs for multi-function, high performance and low cost in the field of the servo motor control are met, and the conventional problem is solved that, when being applied to a servo driving system having a wide speed range, the single use of the position sensing feedback technology or the sensorless position estimation feedback technology fails to satisfy the application for a wide speed range.
    Type: Application
    Filed: December 9, 2010
    Publication date: April 26, 2012
    Inventors: Kuo-Lin CHIU, Chia-Min Ting, Hsin-Hung Chou
  • Publication number: 20110279077
    Abstract: An apparatus includes a driven member, a DC brushless motor, a first signal generation unit configured to output a first signal according to rotation of the DC brushless motor and to change an output value of the first signal each time the DC brushless motor rotates by a predetermined amount, a movement unit configured to move the driven member by a driving force of the DC brushless motor, a second signal generation unit configured to output a second signal each time the driven member moves by the predetermined amount, and a control unit configured to control driving of the DC brushless motor based on the output value of the first signal and a value of a number of times that the second signal is output during a period in which the DC brushless motor rotates by a predetermined amount.
    Type: Application
    Filed: April 27, 2011
    Publication date: November 17, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yoshitsugu Sohara, Shin Genta
  • Patent number: 8013560
    Abstract: The non-linear elastic deformation component included in the angular transmission error of an actuator provided with a wave gear drive is a component of the angular transmission error occurring due to elastic deformation of a flexible externally-toothed gear when the direction of rotation of the motor shaft changes. This component can be analyzed by driving the motor in a sine-wave shape. A model of the non-linear elastic deformation component (non-linear model) obtained from the analysis results is used to store data or a function for compensating for this component in a motor-control device. Compensation for the non-linear elastic deformation component (?Hys) is added to a motor-shaft angle command (?*M) as a compensation input (N?*TE) for feed-forward compensation. As a result, the non-linear elastic deformation component (?Hys) can be effectively reduced, and the positioning precision of the actuator can be improved.
    Type: Grant
    Filed: January 13, 2009
    Date of Patent: September 6, 2011
    Assignee: Harmonic Drive Systems Inc.
    Inventors: Kozo Sasaki, Yoshifumi Okitsu, Toshio Yajima, Makoto Iwasaki
  • Publication number: 20100295495
    Abstract: A servo control apparatus that performs dual-position feedback control and thereby achieves a reduction in position error according to the purpose of machining.
    Type: Application
    Filed: March 3, 2010
    Publication date: November 25, 2010
    Applicant: FANUC LTD
    Inventors: Yasusuke IWASHITA, Tadashi Okita, Yukio Toyozawa, Kazuomi Maeda
  • Patent number: 7813089
    Abstract: In a motor controller, if a failed electric current flow in any one of phases of a motor is detected, a motor control signal is generated, based on a phase other than the phase with the failed electric current flow, in such a manner that a motor electric current matches a required torque except for at a specific rotation angle corresponding to the phase with the failed electric current flow.
    Type: Grant
    Filed: February 25, 2008
    Date of Patent: October 12, 2010
    Assignee: JTEKT Corporation
    Inventor: Hiroshi Suzuki
  • Publication number: 20100188035
    Abstract: It is an object of the present invention to provide a machine tool and a machining method thereof which can execute to machine the workpiece more precisely. The machine tool comprises a tool supporting member 21 relatively movable to a workpiece W along a predetermined axis and supporting a tool 40, a servo motor 32 driving the tool supporting member 21 to the workpiece W along the predetermined axis, a sizing sensor 50 measuring a profile of the workpiece W machined by the tool 40 and outputting a size deviation of measured values from a target profile, and a servo driver 33 driving the servo motor 32 in a feedback control based on the size deviation being output from the sizing sensor 50.
    Type: Application
    Filed: January 12, 2010
    Publication date: July 29, 2010
    Applicant: JTEKT CORPORATION
    Inventors: Satoshi ABETA, Toshihiro Yonezu
  • Publication number: 20090058348
    Abstract: A motor drive control device for controlling a rotational speed of a motor includes: a motor driver for rotationally driving a motor; a correction amount calculating section for detecting a rotational speed of an output of the motor in accordance with an alternate current signal outputted from an FG sensor and detecting a rotational position of a photoconductive drum, which is rotated by a rotational drive force of the motor, in accordance with a pulse outputted from an encoder; a speed controller for generating a speed control signal corresponding to a total correction amount, which is a sum of a correction amount calculated in the correction amount calculating section based on a rotational speed of the motor and a correction amount calculated based on a rotational position of the photoconductive drum, and outputting the generated speed control signal to the motor driver.
    Type: Application
    Filed: August 25, 2008
    Publication date: March 5, 2009
    Applicant: KYOCERA MITA CORPORATION
    Inventor: Gunmun Ryu
  • Patent number: 7408317
    Abstract: A method, and a system of using the method, of controlling a motor having a rated capacity. The method includes determining the motor has been started, determining a plurality of operating parameters of the motor after the motor has started, determining a threshold from a portion of the operating parameters, comparing one of the determined operating parameters with the threshold, and operating the motor at a level corresponding to below the rated capacity when one of the determined operating parameters is greater than the threshold. When an electric motor having a control system according to the present invention lifts a load, drives a machine, or starts other motions, the control system automatically adjusts to a power level that corresponds to the load. In this way, the motor will not be allowed to exert any power or force to the load in excess of what is necessary.
    Type: Grant
    Filed: May 3, 2006
    Date of Patent: August 5, 2008
    Assignee: Wildeck, Inc.
    Inventor: Stephen M. Payne
  • Patent number: 7362071
    Abstract: In an electric rotary excavator (construction machine) 1, when earth pressure acts on a rotary body 4 in an opposite direction to an instructed direction of a lever, a control-system changing means 150 of a rotation control device 100 increases a torque output of an electric motor 5 that drives the rotary body 4. Accordingly, the torque output can properly react against the acting earth pressure, thereby preventing the rotary body from continuing to be rotated in the opposite direction. Therefore, even when the earth pressure becomes large, the work will not be affected. In addition, when the rotary body is rotated on a slope, the rotary body can be prevented from being rotated back greatly due to the weights of the boom and the arm.
    Type: Grant
    Filed: May 13, 2005
    Date of Patent: April 22, 2008
    Assignee: Komatsu Ltd.
    Inventors: Jun Morinaga, Tadashi Kawaguchi
  • Patent number: 6922025
    Abstract: The present invention relates systems and methods for compensating for errors associated with a linear motion system. The systems and methods determines one or more errors associated with the linear motion system and adjusts or corrects an input drive signal associated with the linear motion system to compensate for the one or more errors. The one or more errors of the linear motion system can include cogging errors and ripple errors. The one or more errors can be measured using a measurement system or the one or more errors can be associated with selectable coefficients or parameters, such as standard errors, or device type errors stored in a library.
    Type: Grant
    Filed: February 19, 2003
    Date of Patent: July 26, 2005
    Assignee: Anorad Corporation
    Inventor: James F. Smith
  • Patent number: 6836092
    Abstract: Methods and circuits detect operational information about DC fans powered by pulse width modulation, such as detecting fan presence in a device and/or detecting rotational speed. Output pulses produced by the fan related to the rotational speed are utilized to produce temporary reductions of voltage at the input of a control circuit. The control circuit may count the temporary reductions per unit of time to detect the speed. A pull down resistor may be coupled to the input to pull the input to a continuously low voltage when the DC fan is not present to otherwise provide a pull up at the input, and the control circuit may detect a missing fan from the continuously low voltage. Additionally, or alternatively, a secondary voltage may be provided to the DC fan in addition to the pulse width modulation while a consistently high voltage is provided to the input of the control circuit.
    Type: Grant
    Filed: March 6, 2003
    Date of Patent: December 28, 2004
    Assignee: American Megatrends, Inc.
    Inventor: Clas G. Sivertsen
  • Patent number: 6803736
    Abstract: A system for controlling a regulator equipped with an electric servomotor in a motor vehicle. With reference to an example of an electronic steering system that has an electric-motor steering regulator, output parameters are generated by a model-assisted monitor for evaluating the suitability of a correction for the regulator, and thus criteria for a possible shutdown or to initiate emergency action, as a function of setpoint parameters for the electric servomotor, of instantaneous parameters measured by individual sensors, and of the driving state, and, based on a setpoint behavior of the regulator and on a model simulating the control sections it contains.
    Type: Grant
    Filed: March 5, 2002
    Date of Patent: October 12, 2004
    Assignee: Robert Bosch GmbH
    Inventors: Mathias Hommel, Wolfgang Kraemer
  • Publication number: 20040174131
    Abstract: Methods and circuits detect operational information about DC fans powered by pulse width modulation, such as detecting fan presence in a device and/or detecting rotational speed. Output pulses produced by the fan related to the rotational speed are utilized to produce temporary reductions of voltage at the input of a control circuit. The control circuit may count the temporary reductions per unit of time to detect the speed. A pull down resistor may be coupled to the input to pull the input to a continuously low voltage when the DC fan is not present to otherwise provide a pull up at the input, and the control circuit may detect a missing fan from the continuously low voltage. Additionally, or alternatively, a secondary voltage may be provided to the DC fan in addition to the pulse width modulation while a consistently high voltage is provided to the input of the control circuit.
    Type: Application
    Filed: March 6, 2003
    Publication date: September 9, 2004
    Applicant: American Megatrends, Inc.
    Inventor: Clas G. Sivertsen
  • Patent number: 6664752
    Abstract: A method of correcting positional error in an actuator that is equipped with a motor and a wave gear reduction drive that transmits a motor output to the target load. Positioning error relative to the absolute position of the actuator output shaft is measured, to compile error correction data relating to each position on the rotation of the motor shaft. The rotational position of the motor shaft is detected and rotational position correction information produced by adding error correction values assigned to the position concerned. The rotational positional error information thus produced is used as position feedback information for controlling the positioning of the output shaft.
    Type: Grant
    Filed: February 19, 2002
    Date of Patent: December 16, 2003
    Assignee: Harmonic Drive Systems, Inc.
    Inventors: Naoki Kanayama, Kozo Sasaki
  • Patent number: 6388417
    Abstract: Motor control of a variable reluctance motor is obtained by providing a periodic voltage waveform to a coil of a motor. No coil current control or current or flux feedback is needed to obtain flux waveforms that allow for low-distortion or distortion-free operation of the motor. The periodic voltage waveform may be a sinusoidal or sawtooth signal, for example, and has a substantially zero mean for each cycle of the signal. The periodic voltage waveform may be offset to compensate for the resistance of the coil, and the coil current may be monitored in order to determine the amount of offset required. By providing a zero-mean or substantially zero-mean periodic voltage waveform, the coil current and flux in the gap between the core and the moving part are guaranteed to reach a zero value at some point during each period (or cycle) of the periodic voltage waveform.
    Type: Grant
    Filed: December 6, 1999
    Date of Patent: May 14, 2002
    Assignee: Macrosonix Corporation
    Inventor: F. Joseph Keith
  • Patent number: 5293322
    Abstract: An industrial robot apparatus comprise for controlling an industrial robot and a peripheral unit thereof according to a program so as to load workpieces on a pallet, an abnormal stop unit for detecting an abnormality which occurs in at least either of the industrial robot and the peripheral unit and for stopping both the industrial robot and the peripheral unit, a storage unit for storing a step of the program which is being executed when the abnormal stop takes place, and a removal unit for removing remaining workpieces to be loaded on the pallet in steps following the stored step of the storage unit.
    Type: Grant
    Filed: April 14, 1992
    Date of Patent: March 8, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Nobuo Yagi, Teruo Kurihara, Hisao Kato
  • Patent number: 5239331
    Abstract: A device for braking an electric motor as the drive source of an operating mechanism in camera by means of an electrical circuit is disclosed. This circuit includes a detector for levels of the rotation speed of the motor or of factors of influencing the rotation speed sensed when the motor is supplied with current flowing in a direction to activate the operating mechanism, and control means responsive to the output of the detector for altering the time for which a current flow of reversed direction is supplied to brake the motor.
    Type: Grant
    Filed: March 24, 1992
    Date of Patent: August 24, 1993
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Kobe, Takayuki Tsuboi
  • Patent number: 4611269
    Abstract: An apparatus and a process for detecting an absolute positional value relating to mechanical movement of a member to be measured from a reference point. The apparatus includes a detecting means with a plurality of detectors having periods which are different from one another. Each detector generates an electric signal having a period corresponding to the movement of the member. The signals are stored in a memory. Then, the absolute value of mechanical movement between one of the detectors and the member is specified by using two values. The first value is derived by multiplying the period of the signal corresponding to the one detector by an integer N. The second value is stored in the memory and corresponds to the one detector's partial movement which is less than one period thereof. The value of the integer is decided by using periods and stored values corresponding to other detectors.
    Type: Grant
    Filed: November 15, 1983
    Date of Patent: September 9, 1986
    Assignee: Toshiba Kikai Kabushiki Kaisha
    Inventors: Kimio Suzuki, Jitsuo Toda, Wataru Shimizu
  • Patent number: 4373150
    Abstract: A motor control system including sequencing circuitry for governing the mode of operation of an electric motor in accordance with feedback signals representing selected motor operating parameters further includes modifying circuitry to selectively effect a change in the mode of motor operation in response to an external signal.
    Type: Grant
    Filed: October 8, 1981
    Date of Patent: February 8, 1983
    Assignee: General Electric Company
    Inventor: Allen M. Ritter
  • Patent number: 4059745
    Abstract: An override process control system for regulating a process with a single final control element, such as a valve, from two or more process variables that are interdependent and must not exceed acceptable minimum and maximum limits. The system includes a like number of electronic controllers each acting to compare a respective process variable with a set point to produce an output signal reflecting the deviation of the process variable from the set point. The primary controller responsive to the process variable directly influenced by the setting of the final control element has its output signal applied thereto to regulate this element, whereas the other controllers which are responsive to secondary process variables operate on a standby basis.
    Type: Grant
    Filed: September 29, 1976
    Date of Patent: November 22, 1977
    Assignee: Fischer & Porter Co.
    Inventor: Max H. Gaertner