"step-by-step" Motors In Closed-loop Servos Patents (Class 318/685)
  • Publication number: 20080231220
    Abstract: When a printing instruction is provided, a CPU causes a stepping motor M to drive a developer and calculates the value of a load of the stepping motor M before printing operations are performed. Then, CPU determines whether the value of the load is within a predetermined range stored in advance. If the value is not within the predetermined range, CPU causes a display to display an error message.
    Type: Application
    Filed: March 18, 2008
    Publication date: September 25, 2008
    Applicant: Konica Minolta Business Technologies, Inc.
    Inventors: Takahiro Tsujimoto, Katsuhide Sakai, Kouji Ohara, Shinichi Yabuki
  • Patent number: 7427848
    Abstract: A system for correcting skew of a web of material being fed through a machine includes first and second pinch assemblies placed at a distance transversely to a direction of feeding. First and second stepper motors drive the first and second pinch assemblies, respectively. A control provides first and second pulse trains to drive the first and second stepper motors, respectively. A device determines a value for the skew of the web of material. A method for controlling the system includes establishing first and second corrective pulse train sections for the first and second stepper motors, respectively, in accordance with a determined skew value, and providing first and second pulse trains for driving the first and second stepper motors, respectively.
    Type: Grant
    Filed: November 22, 2006
    Date of Patent: September 23, 2008
    Assignee: Oce-Technologies B.V.
    Inventors: Lodewijk T. Holtman, Peter G. La Vos, Cornelis W. M. Venner
  • Patent number: 7427847
    Abstract: A stepping motor control method including: supplying hold current for holding a rotor of a stepping motor at a prescribed angle to the stepping motor as required while the stepping motor stops; performing a phase change at a frequency lower than a maximum self-start frequency when the stepping motor is rotated, under a state that the hold current is not supplied to the stepping motor, from a stopping state; and then, performing an accelerating process.
    Type: Grant
    Filed: June 13, 2006
    Date of Patent: September 23, 2008
    Assignee: Seiko Epson Corporation
    Inventor: Yasuhiko Yoshihisa
  • Publication number: 20080203961
    Abstract: A controller for a motor driving apparatus switches a direction of electricity flowing through a first coil according to a first lead angle signal obtained based on a first magnetic pole detecting signal and a second magnetic pole detecting signal. The controller switches a direction of electricity flowing through a second coil according to a second lead angle signal obtained based on the first magnetic pole detecting signal and the second magnetic pole detecting signal. Thus, a motor driving apparatus can be configured such that the angle of the rotation center of the rotor with respect to two magnetically sensitive poles can freely be selected.
    Type: Application
    Filed: January 10, 2008
    Publication date: August 28, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Hiromu Yasuda
  • Publication number: 20080164835
    Abstract: A stepping motor controller for controlling a stepping motor which drives a load, including: a load drive state detection section which detects a driving state of the load; and a control section which controls the stepping motor, when a detection result of the load drive state detection section is beyond a prescribed range, so as to maintain a driving speed of the load, and when the detection result of the load drive state detection section is within the prescribed range, so as to control the driving state of the load based on a control pattern.
    Type: Application
    Filed: October 16, 2007
    Publication date: July 10, 2008
    Applicant: KONICA MINOLTA BUSINESS TECHNOLOGIES, INC.
    Inventors: Yoshiki Katayama, Satoshi Ogata
  • Publication number: 20080150468
    Abstract: The invention relates to a method and a circuit layout for the position and/or speed control of a linear drive, in particular a servo drive for a linear robot. An electric motor is supplied via a converter (3) with a control unit (4) and the motor position is determined, in particular in a sensor-free manner or via a position sensor (7). This motor position signal and an acceleration signal generated via an accelerometer (5) provided in the control unit (4) and arranged on the moving part of the linear drive are mathematically converted to a speed signal. This speed signal is used for controlling the drive. The accelerometer (5) is embodied as a microelectromechanical system (MEMS) and integrated into the entrained control unit (4).
    Type: Application
    Filed: May 24, 2006
    Publication date: June 26, 2008
    Inventor: Tomas Kalender
  • Patent number: 7378813
    Abstract: A system for determining a zero position of a yarn guide (25) of a textile winding device for cross-winding yarn into cheeses via a step motor (34). The yarn guide (25), acted upon by the step motor (34), is initially displaced in the direction of its zero position (NS) and positioned at a slow speed against a defined detent (15) downstream of the zero position (NS). Then, the step motor (34) is switched off, causing the rotor (41) of the step motor (34) to drop into one of two possible stop positions (RS1, RS2). Subsequently, the step motor (34) is switched on by an electrical current supply to its stator windings (20A, 20B) such that, when switched off, the rotor (41) of the step motor (34) is in the stop position (RS2) in which the yarn guide (25) is in its zero position (NS).
    Type: Grant
    Filed: January 3, 2006
    Date of Patent: May 27, 2008
    Assignee: Oerlikon Textile GmbH & Co. KG
    Inventors: Günter Scheer, Wilhelm Oehrl, Erwin Peters, Robert Geisler, Dirk Schiffers, Gudrun Doβ, Maximilian Preutenborbeck
  • Publication number: 20080116837
    Abstract: The present invention relates to a circuit for detecting a functional status of an electro-motor. Typical electro-motors need additional components to identify the functional status of the motor. This means additional weight for such motors determining the functional status. According to the present invention a circuit is provided using a part of a motor as a sensor for detecting the functional status of the electro-motor.
    Type: Application
    Filed: September 17, 2004
    Publication date: May 22, 2008
    Applicants: Airbus Deutschland GmbH, Hamilton Sundstrand Corporation
    Inventors: Jurgen Kelnhofer, Thomas Scherer, Steffen Kalsow, Alvy Biccum, John Maljanian, David Leenhouts
  • Publication number: 20080116835
    Abstract: A method for damping vibrations in a stepper motor with micro-stepping control which comprises the steps of identifying the force amplitudes and phase shifts of multiple harmonic detent torques of the stepper motor, such as the first, second and fourth harmonic detent torques, and tuning the stepper motor with different current commands until minimum friction and resistive torque are obtained. Thereafter, a compensating harmonic current derived from said force amplitudes and phase shifts of the said multiple harmonic detent torques is injected into a current command during operation of the stepper motor to compensate for torque ripples.
    Type: Application
    Filed: November 19, 2007
    Publication date: May 22, 2008
    Inventors: Wang Hay Kenneth TSUI, Wai Chuen GAN, Shing Wai TAM, Gang OU, Hon Yu Peter NG
  • Publication number: 20080107435
    Abstract: In a method or system for driving a load element, a drive motor is provided on a drive shaft of the load element that establishes a drive rotation speed of the load element. A rotation torque sensor on the drive shaft emits a load torque signal proportional to a rotation torque. A rotation torque influencing device generates a supplementary torque when the load torque signal deviates from a desired load angle value present when a change has not occurred to a load created by the load element and acting on the drive motor, the supplementary torque being added to a drive torque generated by the drive motor such that a load angle of the drive motor remains substantially constant and uninfluenced by a change of the load.
    Type: Application
    Filed: August 8, 2005
    Publication date: May 8, 2008
    Inventors: Stefan Scherdel, Manfred Viechter
  • Publication number: 20080100253
    Abstract: A stepping motor driving device which makes it possible to reduce electric power consumed by a stepping motor and at the same time suppress degradation of shake correcting performance. A CPU of the stepping motor driving device switches between a first driving method in which a first applied voltage is applied to the stepping motor and a second driving method in which each pulse is divided to apply the first applied voltage over a predetermined time period and then apply a second applied voltage to the stepping motor, depending on the state of the drive frequency of the stepping motor.
    Type: Application
    Filed: October 24, 2007
    Publication date: May 1, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Kousuke Kiyamura
  • Publication number: 20080100249
    Abstract: The lead or lag relationship between the stator and rotor of a stepper motor is monitored on a continuing basis by an incremental encoder, in feed-back relation, and adjusts the lead or lag to within optimum range values to thereby prevent motor stalls and motor cogging.
    Type: Application
    Filed: October 30, 2006
    Publication date: May 1, 2008
    Inventor: David Coutu
  • Patent number: 7362072
    Abstract: A method of controlling a two-phase stepping motor to operate in one of a plurality of operating modes in which output of the motor behaves differently upon encountering obstacle, comprises the steps of: generating an electrical driving current comprising a repeating series of a positive active driving region, a first inactive driving region, a negative active driving region and a second inactive driving region; determining one of the duration of the active driving regions and the duration of the inactive driving regions relative to the other of the durations to thereby cause the motor to operate in a corresponding mode of the operating modes; and applying the driving current to the motor.
    Type: Grant
    Filed: May 9, 2006
    Date of Patent: April 22, 2008
    Inventors: Ferenc Fekete, Ming Ki Au, Celement Chiu Sing Tse, Kenny Chi Ken Lee, Chi Keung Tang, Man Keung Mak, Ming Lam Ng, Kwok Kit Mak, Nai Lap Lee
  • Publication number: 20080084176
    Abstract: A microstepper motor device and method of controlling the device uses a microcontroller that provides current sinusoidal values from at least one array of sinusoidal values to power circuitry of the device in response to control signals. The power circuitry is connected to a stepper motor of the device to supply power signals to the stepper motor using the current sinusoidal values. The microcontroller is configured to index the at least one array of sinusoidal values to the current sinusoidal values in response to the control signals as part of an interrupt service routine of the microcontroller. The microcontroller is further configured to transmit the current sinusoidal values to the power circuitry as part of a non-interrupt routine of the microcontroller.
    Type: Application
    Filed: October 6, 2006
    Publication date: April 10, 2008
    Inventor: Christopher C. Chang
  • Patent number: 7355358
    Abstract: In an implementation of a configurable H-bridge circuit, a high switch is connected to a voltage source and a low switch is connected to ground. The configurable H-bridge circuit includes a first configuration as a motor drive circuit in which the high switch and the low switch are connected together and coupled to drive a motor. The configurable H-bridge circuit also includes a second configuration in which the high switch and the low switch are each configured as a discrete switch that can be coupled as a component switch.
    Type: Grant
    Filed: October 23, 2003
    Date of Patent: April 8, 2008
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Paul D. Bliley, William Jennings, Glenn M. Smith
  • Publication number: 20080079384
    Abstract: A stepping motor controller that alleviates the CPU burden of motor control tasks. An acceleration control starter initializes a pointer register with a given start angle address upon receipt of a control start signal. Duty cycles for different motor angles are previously calculated and stored in a duty cycle memory. A duty cycle selector looks up this memory to select specific duty cycles corresponding to the angle address held in the pointer register. The stepping motor is driven with pulse signals that a pulse generator produces according to the selected duty cycles. An angle address calculator adds a given address increment to the pointer register. A revolution detector detects one revolution of the stepping motor by comparing the angle address of the pointer register with an end angle address, which permits an acceleration constant calculator to change the angular increment upon detection of one revolution.
    Type: Application
    Filed: August 28, 2007
    Publication date: April 3, 2008
    Inventor: Minoru Usui
  • Patent number: 7352150
    Abstract: A stepping motor driving apparatus includes a detector that detects a current supplied to a winding included in the stepping motor, a first offset adding section that adds an offset to the output of the detector, an amplifier that amplifies the output of the first offset adding section, a reference signal generator that generates a reference signal indicating a current limit, a second offset adding section that adds an offset to the output of the reference signal generator, a switching section that supplies a power to the winding when the switching section is turned on and cuts off a power to the winding when the switching section is turned off, and a PWM controller that turns on the switching section every predetermined period, and turns off the switching section when the output of the amplifier exceeds the output of the second offset adding section.
    Type: Grant
    Filed: July 10, 2006
    Date of Patent: April 1, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroshi Fujinaka, Naoki Kawamoto
  • Patent number: 7348753
    Abstract: A fan motor includes: a single-phase stepping motor including a stator excited by applying an electric current to a coil to function as a single-phase magnetic pole, and a rotor which has a permanent magnet magnetized to a single phase and rotates as the magnetic pole of the stator changes; an impeller which is rotated by a rotating shaft of the rotor; and a drive circuit for controlling an application of a current to the coil. The drive circuit applies pulse voltage to the coil and the coil constant is set so that a mean value of the current applied to the coil is 10 mA or smaller.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: March 25, 2008
    Assignee: NIDEC Copal Corporation
    Inventors: Takashi Kasahara, Hiroyuki Shingai, Masaaki Takagi
  • Patent number: 7345447
    Abstract: A method and a system are disclosed for adaptively controlling a stepper motor to produce a required torque output based on selection information provided by a sensor or a user/user interface which, in combination with a selector, selects a torque-related value. The selection information provided to the selector for selecting the stepper motor torque-related value may be, for example, the size or thickness of material being handled or the number of accumulated sheets for processing. The torque-related value is predetermined through experimentation and loaded into a lookup table stored in the memory of a motion control system board. The selected torque-related value is provided to a stepper motor driver which supplies the appropriate drive signal(s) to the stepper motor.
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: March 18, 2008
    Assignee: Pitney Bowes Inc.
    Inventors: George J. Doutney, James A. Fairweather, Gary S. Jacobson, Michael J. Lorello
  • Patent number: 7342690
    Abstract: An image reading apparatus of the present invention can suppress an image distortion caused by the vibration of a carriage by varying at least one of the level of a current supplied to a drive motor in accordance with a variation of an environmental temperature and an acceleration distance.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: March 11, 2008
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventor: Tetsuya Sato
  • Publication number: 20080054198
    Abstract: A method and to a corresponding apparatus for processing information carriers, in particular for reading out storage phosphor plates (2) for storing X-ray information, an information carrier (2) and/or a container (1) in which the information carrier (2) is located being processed, in particular being moved and/or fixed, by at least one mechanical processor (13), the processor (7) being driven by at least one stepper motor (10), and information from the information carrier (2) being read out and/or written in the information carrier.
    Type: Application
    Filed: August 9, 2007
    Publication date: March 6, 2008
    Applicant: AGFA HEALTHCARE N.V.
    Inventors: Vladimir Zemanek, Bernd Gerstlauer, Thomas Zehetmaier, Alfred Huber
  • Patent number: 7339342
    Abstract: A stepper motor controlling apparatus has a driver which drives a stepper motor in response to an input pulse signal, a PWM controlling section which changes a duty ratio of the pulse signal fed to the driver to control a rotation of the stepper motor, a pulse encoder which rotates in response to the rotation of the stepper motor, and outputs a pulse according to a position of a moving object, a position counter which counts the pulse output from the pulse encoder to sense a present position of the moving object, and a pulse rate controlling section which controls an update latency time of the pulse signal according to a deviation between a target position of the moving object and the present position.
    Type: Grant
    Filed: December 14, 2005
    Date of Patent: March 4, 2008
    Assignee: Yokogawa Electric Corporation
    Inventors: Naoyuki Harada, Hiroshi Otawa
  • Patent number: 7332887
    Abstract: An image forming apparatus includes a stepping motor that drives a rotor by rotating in accordance with an input of a drive pulse, a drive pulse profile storage portion that stores the drive pulse profiles corresponding to temporal changes of the drive pulse inputted in the stepping motor at starting, the drive pulse profile storage portion storing at least a first load profile corresponding to the first drive pulse profile for a first load driving the rotor and a second load profile corresponding to the second drive pulse profile for a second load driving the rotor, which is larger than the first load and a profile setting portion that sets the drive pulse profile in accordance with the load for driving the rotor, as the drive pulse profile of pulses inputted into the stepping motor, among the drive pulse profiles stored in the drive pulse profile storage portion.
    Type: Grant
    Filed: April 19, 2006
    Date of Patent: February 19, 2008
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Teruyo Ryuzaki
  • Patent number: 7333400
    Abstract: The invention concerns a control system for a servomechanism comprising a control member that can move between first and second positions defining a variable electric quantity respectively between a minimum quantity and a maximum quantity, characterized in that the control system further comprises low voltage powering means, voltage increase means connected to the terminals of the low voltage powering means and delivering a high voltage at output, means for measuring a value of the variable electric quantity, powered by the low voltage powering means when the high voltage is being generated, and means for regulating the voltage increase means arranged to increase the high voltage delivered for a variation in the measured electric quantity value lower than a variation threshold determined by the servomechanism, respectively to decrease the high voltage delivered for a variation in the measured electric quantity values higher than the determined variation threshold.
    Type: Grant
    Filed: November 22, 2006
    Date of Patent: February 19, 2008
    Assignee: ETA SA Manufacture Horlogère Suisse
    Inventors: Fabien Blondeau, Emmanuel Fleury, Pierre-André Meister, André Zanetta
  • Patent number: 7330009
    Abstract: A method, apparatus, and program for driving a motor in a feedback control system, capable of suppressing oscillation of the motor rotational speed are disclosed. A motor drive controller includes a drive motor, a detector, and a motor drive controller. The drive motor drives a moving body around a target speed. The detector detects a current moving speed of the moving body and outputs it as a detector pulse signal. The controller calculates a difference between the current moving speed and the target moving speed, calculates a control value based on the difference, calculates a pulse rate of a drive pulse signal based on the control value after having controlled the control value to be within a predetermined value, and controls the drive motor based on the pulse rate.
    Type: Grant
    Filed: July 19, 2004
    Date of Patent: February 12, 2008
    Assignee: Ricoh Co., Ltd.
    Inventors: Toshiyuki Andoh, Tadashi Shinohara, Yuuji Matsuda, Kazuhiko Kobayashi, Nobuto Yokokawa, Masato Yokoyama, Yohhei Miura, Toshiyuki Takahashi, Jun Hosokawa
  • Patent number: 7327115
    Abstract: There are included a control circuit to control sequence of excitation of a stepping motor, a switching circuit to switch electric power to be supplied to the stepping motor based on an instruction from the control circuit, and a stop circuit to stop an operation of the switching circuit in a case where temperature of the switching circuit becomes a specified temperature or higher, and the control circuit controls the switching circuit in a mode where the stop circuit operates before the stepping motor is damaged by heat.
    Type: Grant
    Filed: March 7, 2006
    Date of Patent: February 5, 2008
    Assignee: Seiko Epson Corporation
    Inventor: Yasuhiko Yoshihisa
  • Patent number: 7327116
    Abstract: A stepper motor accelerating system is used for accelerating a stepper motor from a current rotational speed to a target rotational speed. The stepper motor accelerating system comprises a controller, a pulse generator, and a driver. The controller stores a safety acceleration curve. The safety acceleration curve is defined by shifting a characteristic curve of the stepper motor with a safety margin. The controller compares the current rotational speed and the target rotational speed with the safety accelerating curve, and then gets two corresponding points on the safety accelerating curve. The controller generates a real accelerating curve based on these two corresponding points. The pulse generator receives the real accelerating curve and converts to a pulse signal. The driver receives the pulse signal, and then drives the stepper motor with the pulse signal. The present invention accelerates the stepper motor base on the safety accelerating curve.
    Type: Grant
    Filed: August 25, 2006
    Date of Patent: February 5, 2008
    Assignee: Transpacific Plasma, LLC
    Inventor: Ping-Hung Kuo
  • Patent number: 7323839
    Abstract: A direct current motor controlling method includes a mean for transforming a duty signal to computed value by a microprocessor unit. The microprocessor unit computes the computed value and then produces a target value by executing a dichotomy method, a rotation method and a transformed function, capable of reducing executing time and executing load of the microprocessor unit and saving memory space. The microprocessor unit sends a frequency signal to a driving circuit unit according to the target value. The driving circuit unit receives the frequency signal and then provides a driving voltage to a power switch. The power switch provides a voltage to a direct current motor or not according to the driving voltage for controlling output performance of the direct current motor.
    Type: Grant
    Filed: September 5, 2006
    Date of Patent: January 29, 2008
    Assignee: Cheng Uei Precision Industry Co., Ltd.
    Inventor: Lung-Chieh Chen
  • Patent number: 7323844
    Abstract: A circuit for the control of a stepper motor having a rotor configured as a permanent magnet and a stator configured of at least first and second energized excitation coils enclosing the rotor. Each end terminal of the first excitation coil is connected to the positive pole of the supply voltage over a switching element and each end terminal of a second excitation coil is connected to the negative pole of the supply voltage over a switching element. The central contacts of both excitation coils are connected to each other.
    Type: Grant
    Filed: July 1, 2005
    Date of Patent: January 29, 2008
    Assignee: Visteon Global Technologies, Inc.
    Inventor: Walter Mayer
  • Patent number: 7324245
    Abstract: In the present invention, an image reading apparatus and the like which is provided with a driving device (21) capable of changing its rotational speed, includes an inertial load changing device 26 for changing the inertial load of a rotating body (23) of the driving device (21). The inertial load changing device 26 includes an inertial body (27) which is adjacently disposed to the rotating body (23) and an interlock unit 28 for attaching the inertial body 27 to the rotating body 23 to create an integral rotation so as to change the inertial load of the rotating body (27). The inertial bodies is provided by single or plural number. The plural number of inertial bodies (27) is individually attached to the rotating body (23) by means of the interlock unit 28 in order to change the inertial load of the rotating body in several levels.
    Type: Grant
    Filed: March 18, 2003
    Date of Patent: January 29, 2008
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventor: Toshihiro Sone
  • Publication number: 20080012523
    Abstract: A control device for a stepping motor of the present invention stores setting data for controlling a state of the stepping motor in a data storage unit for each of a plurality of basic control items obtained by classifying control from activation to stoppage of the stepping motor. In addition, the control device for the stepping motor includes a plurality of modules that execute processing with respect to the basic control items and a module control unit that specifies the order of executing the processing by the plurality of modules in advance, and controls the stepping motor by operating the modules in accordance with the specified executing order based on the setting data stored in the data storage unit.
    Type: Application
    Filed: May 2, 2007
    Publication date: January 17, 2008
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hidenori Kobayashi, Shunichi Ono, Kazumasa Takada, Takashi Okano
  • Patent number: 7307398
    Abstract: A image processing device includes a first module, a motor system connected to the first module and capable of pushing the first module to move forward, a selector connected to a plurality of loading circuits included in the motor system and capable of selecting a loading circuit among the plurality of loading circuits and setting the selected loading circuit as a loading of the motor system, and a controller electrically connected to a driver included in the motor system and capable of controlling a speed of the motor system pushing the first module.
    Type: Grant
    Filed: March 15, 2005
    Date of Patent: December 11, 2007
    Assignee: BenQ Corporation
    Inventors: Chun-Jen Lee, Yueh-Chi Hung
  • Patent number: 7304449
    Abstract: A stepping motor control apparatus includes a control circuit to control the excitation sequence of a stepping motor, and a switching circuit to switch electric power to be supplied to the stepping motor based on an instruction from the control circuit, and when the stepping motor is rotated from a stop state, the control circuit executes an acceleration processing after sending pulses at a frequency not higher than a maximum self-start frequency.
    Type: Grant
    Filed: March 7, 2006
    Date of Patent: December 4, 2007
    Assignee: Seiko Epson Corporation
    Inventor: Yasuhiko Yoshihisa
  • Patent number: 7301300
    Abstract: A method and a circuit arrangement for operating stepper motors or other appropriately dimensioned synchronous motors is disclosed in which between a first operational mode for normal motor operation and a second operational mode for detecting an operating state of the motor like for example its load can be switched. The method and the circuit arrangement is especially provided for determining a reference position of the motor without sensors by driving the motor against a mechanical stop wherein an increase of the load which is caused by this, is detected as a change of the operating state (FIG. 1).
    Type: Grant
    Filed: June 7, 2003
    Date of Patent: November 27, 2007
    Assignee: Trinamic Motion Control GmbH & Co. KG
    Inventor: Lars Larsson
  • Publication number: 20070241716
    Abstract: An optical disk drive capable of detecting occurrence of step-out or tooth jump in a mechanism for transferring an optical pickup. The optical pickup is transferred in a radial direction of the optical disk by means of a stepping motor. Upon receipt of a seeking operation command from a host machine, a control section drives the stepping motor by way of a controller, to thus cause the optical pickup to perform seek up to a target address. When logical contradiction has arisen in a stepper pointer showing the amount of rotation of the stepping motor, the control section determines that step-out or tooth jump has arisen. Moreover, even when a difference exists between an address indicated by the value of the stepper pointer and an actual address, step-out or tooth jump is determined to have arisen. When the step-out or tooth jump has arisen in the transfer mechanism, the rotational speed of a spindle motor or the rotational speed of the stepping motor is decreased.
    Type: Application
    Filed: March 16, 2007
    Publication date: October 18, 2007
    Applicant: TEAC Corporation
    Inventors: Hideki Kubo, Kazuhiko Kameda
  • Publication number: 20070216335
    Abstract: A stepping motor controlling device according to the present invention includes lead angle computing means which computes a lead angle according to the load torque current deviation of the stepping motor, adding means which adds an angle command to the lead angle to determine a winding exciting angle and voltage applying means which applies a voltage according to the winding exciting angle to the stepping motor.
    Type: Application
    Filed: March 15, 2007
    Publication date: September 20, 2007
    Inventors: Akio Takemori, Yoshifumi Kuwano, Hiroaki Taka, Yoshitaka Iwaji
  • Patent number: 7271554
    Abstract: A motor-driving circuit drives a plurality of motors of different types. The motor-driving circuit includes a plurality of H-bridge circuits for outputting driving signals to the motors, a controller for controlling the plurality of H-bridge circuits, a setting section for setting up the controller, and terminals for inputting setting data.
    Type: Grant
    Filed: July 26, 2004
    Date of Patent: September 18, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventor: Takayuki Aizawa
  • Patent number: 7268512
    Abstract: A pattern register stores an excitation pattern of stepping motors. A first pattern control unit reads out an excitation pattern for n bits from a predetermined address of a pattern register for supplying the same to an external motor driver. A second pattern control unit reads out an excitation pattern for the same n bits as in the first pattern control unit from a predetermined address of the pastern register and supplies the same to an external motor driver. An output control unit selectively outputs a first output mode for using the first pattern control means and the second pattern control means independently, or a second output mode for using them in an interlocked manner.
    Type: Grant
    Filed: February 21, 2003
    Date of Patent: September 11, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yukimasa Iseki
  • Patent number: 7262575
    Abstract: Methods and apparatus for precise positioning of an object using linear actuators based on linear stepper motors operating in microstepping or full step mode, a control algorithm based on compensation table, and a calibration apparatus for obtaining the compensation table.
    Type: Grant
    Filed: November 21, 2005
    Date of Patent: August 28, 2007
    Assignee: Bio-Rad Laboratories, Inc.
    Inventors: Nenad Kircanski, Amir Sadri, Milija Timotijevic, Zhiliang Xu, Manja Kircanski, Neven Nikolic
  • Patent number: 7253575
    Abstract: A highly versatile optical shutter for industrial and scientific applications is disclosed. The has a aperture which defines a light path through the shutter, and a shutter vane or blade that is moved into and out of the light path using a precision, microprocessor controlled motor, such as a stepping motor. Preferably, the motor is mounted on the shutter housing using a shock absorbing material. A control unit associated with the shutter comprises the microprocessor, a motor driver, preferably one which is capable of microstepping the motor, and a non-volatile memory device, such as EEPROM, which stores a plurality of shutter control programs defining different trajectories of the shutter vane. Different programs may be used, for example, to maximize shutter speed or frequency, or to minimize vibrations.
    Type: Grant
    Filed: November 8, 2004
    Date of Patent: August 7, 2007
    Assignee: Sutter Instrument Company
    Inventors: Jack Belgum, Ximin Wang, Dale Flaming
  • Patent number: 7245106
    Abstract: A controller of a pulse width modulation signal-driven device, includes: an instruction input of operating the pulse width modulation signal-driven device; a control section generating a control clock which operates the pulse width modulation signal-driven device; a frequency modulator frequency-modulating the control clock, to thereby give to the control clock a frequency variation in a predetermined frequency range; a frequency varier generating a modulation signal inputted to the frequency modulator; and a first switching member driving the switching element which flows a predetermined drive current to the pulse width modulation signal-driven device based on the frequency-modulated control clock. The frequency varier includes: a first signal generator setting a range of diffusing a switching noise in a frequency range, and a unit for shifting a frequency band of the switching noise by giving a predetermined offset voltage to an output voltage of the first signal generator.
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: July 17, 2007
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Kentaro Shin, Yasuaki Hayami, Kraisorn Throngnumchai
  • Patent number: 7239108
    Abstract: A method for referencing a polyphase stepper motor by monitoring the current step response in at least one driven phase is presented. The coil current step response is compared to past step responses in order to determine when an increase in or maximum load is present. A combination of step to step variance, step response variance from mean current magnitude, and average current magnitude variance, as well as other measures can be combined to create an algorithm output. The output is compared to a pre-determined threshold and if the value is greater than the threshold, the motor is commanded to halt its position, which remains magnetically synchronous. This position is then used as a reference point to zero, or to home the motor.
    Type: Grant
    Filed: January 31, 2006
    Date of Patent: July 3, 2007
    Assignee: Texas Instruments Incorporated
    Inventor: Eric P. Best
  • Patent number: 7231139
    Abstract: A system and method for reducing fan noise by controlling the drive current to the fan motor. In one embodiment the system approximates a linear drive using a number of transistors in parallel and sequentially deploying the transistors. In another embodiment, a scheme is used to activate and deactivate transistors in discrete steps thereby achieving the benefits of the linear controller topology.
    Type: Grant
    Filed: September 29, 2005
    Date of Patent: June 12, 2007
    Assignee: Asahi Kasei Microsystems Co., Ltd.
    Inventors: Mark E Collins, Sumner B Marshall, III
  • Patent number: 7224140
    Abstract: This invention detects a stall in a stepper motor by determining a motor winding current for each stepper pulse and determining if the winding current of a particular stepper pulse meets predetermined criteria. The motor winding current may be determined by measuring a voltage across an ON field effect transistor during a stepper pulse and calculating a winding current using an assumed ON field effect transistor resistance. The predetermined criteria may by a calculated motor winding current greater than a predetermined threshold, greater than prior pulse by more than a predetermined threshold or greater than a prior pulse by more than a predetermined factor.
    Type: Grant
    Filed: January 31, 2006
    Date of Patent: May 29, 2007
    Assignee: Texas Instruments Incorporated
    Inventors: Mohammed S. Arefeen, Jim D. Childers
  • Patent number: 7215091
    Abstract: A method of the invention is for controlling a DC printer motor with a motor driver during a potential stall of the DC printer motor. One step of the method includes detecting the start of the potential stall of the DC printer motor. Another step includes thereafter during the potential stall using an input to the motor driver which corresponds to a pulsed desired motor voltage. A further step includes outputting from the motor driver a control voltage to the DC printer motor based on the input. In one example of the method, the start of a potential stall of a DC printer motor is detected at least one time when a printhead carrier moved by a DC printer motor of an inkjet printer encounters a capping device of the inkjet printer while returning to the printer sidewall home position of the printhead carrier.
    Type: Grant
    Filed: January 3, 2003
    Date of Patent: May 8, 2007
    Assignee: Lexmark International, Inc.
    Inventor: Marc A. Herwald
  • Patent number: 7208905
    Abstract: The driving method of the present invention is a driving method to drive a stepping motor driven by a predetermined driving pulse, by the servo driving method, and is characterized in that a predetermined sampling period is set, and the generation condition of the driving pulse to drive the stepping motor is set at the sampling periods. Thereby, the stepping motor can be driven while the most suitable driving condition is determined at the predetermined sampling periods. That is, since the driving condition of the stepping motor can be changed at the sampling periods, even when the stepping motor driven by the driving pulse is the driving source, appropriate servo control can be realized.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: April 24, 2007
    Assignee: Konica Minolta Photo Imaging, Inc.
    Inventor: Kazuhiro Shibatani
  • Patent number: 7199546
    Abstract: It is disclosed the motor stop control device having the stepping motor 49 as the drive source of the reel 3 on which a plurality of symbols are formed, the motor stop control device being utilized in the reel-type gaming machine 1 and stopping the stepping motor 49 corresponding to the stop instruction from an external. When the stop instruction of the stepping motor 49 occurs based on the instruction from an external, the main CPU 31 drops the voltage value added to the stepping motor which is rotating at the constant speed to the voltage value lower than such voltage value and executes the stop process of the stepping motor 49 by 2-phase excitation.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: April 3, 2007
    Assignee: Aruze Corp.
    Inventors: Takao Nireki, Yuuichirou Suzuki
  • Patent number: 7197390
    Abstract: A novel system for adaptively controlling an electric vehicle to maintain desired speed under variable driving conditions. The system includes a control circuit for producing a control signal to control an electric motor of the vehicle. The control signal is formed based on a control current required to achieve the desired speed. The control strategy selection circuit is configured in the system to determine a motor control scheme that provides an appropriate waveform profile of the control current.
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: March 27, 2007
    Assignee: Wavecrest Laboratories LLC
    Inventors: Guohui Yuan, Boris Maslov
  • Patent number: 7193386
    Abstract: The present invention relates to an apparatus for driving a stepping motor, including a plurality of push-pull circuits each of which is capable of controlling a push state in which a current is supplied to a terminal and a pull state in which a current is drawn through the terminal and which are connected to coils to operate the stepping motor utilizing the bipolar driving. In the apparatus of the present invention, at least one of the push-pull circuits is connected to a common terminal having one ends of the coils of different phases connected thereto, thereby reducing the number of circuits and driving lines.
    Type: Grant
    Filed: May 29, 2003
    Date of Patent: March 20, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hiroyoshi Misumi
  • Patent number: RE40370
    Abstract: An electronic watch 400 which comprises a power supply 401 and a watch circuit 402.
    Type: Grant
    Filed: March 7, 2001
    Date of Patent: June 10, 2008
    Assignee: Citizens Holdings Co., Ltd.
    Inventors: Koichi Sato, Fumio Kanno