Digital Comparison Patents (Class 318/601)
  • Patent number: 7813978
    Abstract: A method for tracking and approving legal expenses incurred by a business entity using a legal budgeting computer system is provided. The method includes creating a legal matter reflecting legal work to be performed by an outside counsel, creating a purchase order for the legal matter including a budgeted amount which is expected to be paid to the outside counsel for performing the legal work, receiving from the outside counsel an invoice, and prompting an account manager to designate a method of reimbursement for the invoice including at least one of paid at close, charge to good faith, charge to loan, customer to wire money, and a non-reimbursable charge to cost center. The method also includes submitting the invoice to an approval process, validating the approved invoice amount, paying the approved invoice amount, and automatically reconciling the approved invoice amount.
    Type: Grant
    Filed: May 3, 2004
    Date of Patent: October 12, 2010
    Assignee: GE Corporate Financial Services, Inc.
    Inventors: Preston H. Abbott, Patricia Anne Hussey, Carolyn Katherine Amone, Prasanna Ramaswamy, Ganesh Narayanan, Janice Pearson, Patricia O'Brien-Gilbert
  • Publication number: 20100253275
    Abstract: The present invention is a parallel kinematic linkage based micro-positioning system that can provide precise movement at the micron and sub-micron level of a payload that is compatible with an existing automation system. The system has a motor controller, a digital signal processor, a base frame, a first motor, a first cranking arm with a first connecting link and an intermediate stage that mounts a second motor that is attached to a second cranking arm with a second connecting link. There is also an output stage (also called a table) that is precisely moved by the second cranking arm and a first and second optical linear encoder used in combination with the first and second motor and the first and second cranking arm forming a first motor assembly that converts operational data into a plurality of highly precise X-axes and Y-axes payload linear movements.
    Type: Application
    Filed: April 5, 2010
    Publication date: October 7, 2010
    Inventor: Bhargav Ishwarlal Gajjar
  • Patent number: 7804267
    Abstract: In a correction method for a microprocessor-controlled digital regulation of a drive motor, wherein the measurement arrangement used for the regulation of the motor is simplified. recognizing that the real value surveying cannot always be implemented periodically by the microprocessor at the requested point in time, making sporadic measurement errors of a simplified measurement arrangement ineffectual, in accordance with the method individual measurement values with a sudden change are read out and correction values are used instead of these for the regulation.
    Type: Grant
    Filed: May 15, 2008
    Date of Patent: September 28, 2010
    Assignee: Francotyp-Postalia GmbH
    Inventor: Ralf Müller
  • Patent number: 7804268
    Abstract: An apparatus and method of controlling injection in an electric injection molding machine including a motor and a screw. The apparatus has an encoder detecting a current position of the screw and outputting the detected position as an encoding signal, a memory storing reference positions of the screw according to a drive of the motor by the passage of time, and a current controller checking an elapse of time that the screw moves from a previous position to a current position through receiving the encoding signal from the encoder, reading out a section of time corresponding to the checked elapse of time from the memory, and controlling a current value applied to the motor based on a difference between a reference position of the screw corresponding to the read-out section of time and a current position of the screw.
    Type: Grant
    Filed: November 7, 2007
    Date of Patent: September 28, 2010
    Assignee: LS Mtron Ltd.
    Inventors: Kyong-ho Park, Jong-min Lee
  • Patent number: 7791305
    Abstract: The control apparatus 10 of a servo motor of the present invention has a position control unit 11 controlling the position of a servo motor 33, a speed control unit 12 controlling a speed of the servo motor 33, a distributing unit 13 dividing the speed command output by the position control unit 11 into a filtered part Vf which is filtered to suppress vibration and a nonfiltered part Vnf, a filtering unit 14 receiving as input the filtered part Vf and filtering and outputting the filtered part Vf, and an adder unit 15 adding the filtered part Vf filtered by the filtering unit 14 and the nonfiltered part Vnf and outputting the result to the speed control unit 12.
    Type: Grant
    Filed: January 17, 2008
    Date of Patent: September 7, 2010
    Assignee: Fanuc Ltd
    Inventors: Yasusuke Iwashita, Tadashi Okita, Hiroyuki Kawamura
  • Patent number: 7750592
    Abstract: When performing numerical control of a rotary table, the moment of inertia and the center of gravity of a control target change because of a placed object fixed onto the rotary table. A rotary table to which a placed object has been fixed serves as a target plant, the actual motion of this is compared with motion calculated by an identification model of the target plant, and a torque command value is corrected. The identification model comprises a term pertaining to angular acceleration and a term pertaining to angle of rotation, and by including the term pertaining to angle of rotation, correction of a torque command corresponding to a change in the center of gravity can be performed.
    Type: Grant
    Filed: January 3, 2008
    Date of Patent: July 6, 2010
    Assignee: Okuma Corporation
    Inventor: Satoshi Eguchi
  • Patent number: 7723942
    Abstract: An integrated motor and position sensor achieves motion between a moving portion and a stationary portion by electrically energizing poles to interact with magnetics respectively on the moving and stationary portions. The position sensor includes a plurality of sensing coils placed to intercept the magnetic flux between a plurality of the poles and the magnetics. The outputs from these coils are fed to a microprocessor DSP through an internal or external A/D converter. The microprocessor or DSP decodes the measured voltages using resolver strategies to produce a position, velocity or acceleration measurement.
    Type: Grant
    Filed: February 9, 2009
    Date of Patent: May 25, 2010
    Assignees: QuickSilver Controls, Inc.
    Inventor: Donald P. Labriola, II
  • Patent number: 7719224
    Abstract: The invention includes a system and method for generating simulated encoder outputs in a control system. An output pulse width between reference position inputs is computed, the output pulse width being based upon a difference between an updated reference position input and a previous reference position input, and upon a time interval between the reference position inputs. Next, a plurality of simulated encoder pulses is output between updates of the reference position input based upon the computed output pulse width. The output pulse is thereafter adjusted in a closed loop manner between updates of the reference position input.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: May 18, 2010
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Juntao Quan, Adrian Wirth
  • Patent number: 7659681
    Abstract: A servomotor in a numerical controller is controlled by automatically switching to either pressure control or position control in association with the command which is smaller from among a command obtained by performing pressure feedback control and a command obtained by performing position feedback control. When switched to pressure control while moving according to a movement command, the output of the movement command is terminated halfway, and the command in the next block is executed, and pressure control of the next command is immediately started. As a result, a wasteful time is eliminated, and a cycle time of the operation can be shortened.
    Type: Grant
    Filed: August 8, 2007
    Date of Patent: February 9, 2010
    Assignee: Fanuc Ltd
    Inventors: Yasushi Onishi, Tetsuo Hishikawa, Keisuke Tsujikawa
  • Publication number: 20100001679
    Abstract: An acceleration control apparatus for servo control of a computer numerical control (CNC) machine comprises a digital filter. The digital filter is obtained by selecting a cutoff frequency of an analog filter and using a pole-zero matched method to transform an analog filter. The low-pass digital filter includes a signal input unit, a signal input register unit, a signal operation unit, a signal output unit, and a signal output register unit.
    Type: Application
    Filed: December 31, 2008
    Publication date: January 7, 2010
    Applicant: FOXNUM TECHNOLOGY CO., LTD.
    Inventors: RONG-HWANG HORNG, WEI-DER TANG, YAW-SHEN LAI, JHY-HAU CHIU
  • Publication number: 20090261772
    Abstract: A method and apparatus for determining speed of a stepper motor. In one embodiment of the method, a first terminal of a first coil of the stepper motor is coupled to an input of a multibit digital-to-analog (A/D) convertor. The stepper motor's a rotor is rotated about an axis while the first terminal is coupled to the multibit A/D convertor. An analog signal is induced at the first terminal generating while the rotor is rotating about the axis. The multibit A/D convertor receives the analog signal induced at the first terminal. The multibit A/D convertor generates a plurality of multibit digital signals in response to receiving the analog signal. The multibit digital signals can be processed to determine the rotational speed at which the rotor was rotating when the A/D convertor generated the plurality of multibit digital signals.
    Type: Application
    Filed: April 16, 2008
    Publication date: October 22, 2009
    Inventors: Timothy J. Grai, Nathan W. John
  • Patent number: 7576503
    Abstract: A brushless motor controller for use in a fuel pump detects a rotor phase based on an induced voltage in each phase coil of a brushless motor, and controls energization of the each phase coil based on the detected rotor phase. A control circuit of the controller is arranged to check the induced voltage by using three reference voltages as judgment values, convert a result of the check into a logic signal, and detect the rotor phase based on a prescribed change of the logic signal.
    Type: Grant
    Filed: November 27, 2006
    Date of Patent: August 18, 2009
    Assignee: Aisan Kogyo Kabushiki Kaisha
    Inventors: Shingo Nakanishi, Masahiro Kako
  • Publication number: 20090195207
    Abstract: The present invention discloses a servo control circuit comprising: a first node for receiving a control voltage; a second node for receiving a feedback voltage; an operational amplifier controlling a current on a path according to the voltages at the first and second nodes, the path including an internal voltage node thereon; an analog to digital converter (ADC) for converting the voltage at the internal voltage node to a digital signal; and a control logic circuit for generating a servo control signal according to the digital signal.
    Type: Application
    Filed: February 6, 2008
    Publication date: August 6, 2009
    Inventor: Hui-Yen Hsieh
  • Publication number: 20090085507
    Abstract: The invention includes a system and method for generating simulated encoder outputs in a control system. An output pulse width between reference position inputs is computed, the output pulse width being based upon a difference between an updated reference position input and a previous reference position input, and upon a time interval between the reference position inputs. Next, a plurality of simulated encoder pulses is output between updates of the reference position input based upon the computed output pulse width. The output pulse is thereafter adjusted in a closed loop manner between updates of the reference position input.
    Type: Application
    Filed: September 28, 2007
    Publication date: April 2, 2009
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Juntao Quan, Adrian Wirth
  • Patent number: 7504785
    Abstract: A system to control the fixed mass/spring mechanical resonance of the motor in conjunction with a model of the motor that estimates the present position and allows the determination of the motor stator voltage pattern which will produce the requested output force. This approach effectively eliminates the electrical restoring force from the motor dynamics and minimizes the problems associated with the varying resonant frequency of the motor.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: March 17, 2009
    Assignee: Agilent Technologies, Inc.
    Inventor: Paul Lewis Corredoura
  • Publication number: 20090009127
    Abstract: A motor driving control device includes a current instruction value computing section 31 which computes a current instruction value for driving a brushless motor 12, a motor current detector 38 which detects a motor current of the brushless motor 12, a current controller 34 which computes a voltage instruction value based on the current instruction value and the motor current, and a rotation information detector 22 which detects an electric angle and a rotation angular velocity of the brushless motor, and the motor driving control device includes a disturbance compensation voltage computing section 41 which computes a disturbance compensation voltage value base on the current instruction value, the electric angle of the brushless motor, and the rotation angular velocity of the brushless motor, and a feed-forward compensator 35 which corrects a voltage instruction value outputted from the current controller based on the disturbance compensation voltage value computed by the disturbance compensation voltage com
    Type: Application
    Filed: July 3, 2008
    Publication date: January 8, 2009
    Applicant: NSK LTD.
    Inventors: Yousuke IMAMURA, Lilit KOVUDHIKULRUNGSRI, Shuji ENDO, Kenji MORI
  • Publication number: 20080303475
    Abstract: Methods and systems are provided for controlling permanent magnet machines. The method includes determining a maximum torque of the PM machine based on an error between a commanded d-axis flux and an estimated d-axis flux of the PM machine, and adjusting a torque command based on the maximum torque. The error associated with a variation between a current temperature and a nominal temperature of the PM machine.
    Type: Application
    Filed: June 7, 2007
    Publication date: December 11, 2008
    Inventors: Nitinkumar R. Patel, Brian A. Welchko, Bonho Bae, Steven E. Schulz
  • Publication number: 20080174259
    Abstract: In a device, such as measuring or control signal transmitter, generating an analog current or voltage output signal, absolute values of output variables are continuously measured and regulated to ensure the correctness of the signal. The actual current or voltage value of an analog output signal is measured and digitized (206), a difference (e) between the digitized actual current or voltage value and the desired current or voltage value is defined (300), and the generation (200, 202, 204, 205) of the analog output signal is controlled (304) by means of a digital control signal (Enable, Direction) so as to decrease the difference.
    Type: Application
    Filed: January 22, 2008
    Publication date: July 24, 2008
    Applicant: ABB OY
    Inventor: Erkki MIETTINEN
  • Patent number: 7291999
    Abstract: A method of analyzing a limited rotation motor system is disclosed. The method includes the step of providing a motor control frequency domain signal that is representative of a frequency domain representation of the motor control signal responsive to a first digital signal that is representative of a motor control signal. The method also includes the step of providing a position detection frequency domain signal that is representative of a frequency domain representation of the position detection signal responsive to a second digital signal that is representative of a position detection signal.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: November 6, 2007
    Assignee: GSI Group Corporation
    Inventor: Yuhong Huang
  • Patent number: 7282883
    Abstract: A system for moving a barrier between limit positions, includes an operator motor assembly mounted proximate to the barrier, wherein at least a portion of the motor assembly is movable between an operating position and a locking position with the motor assembly blocking movement of the barrier. A bias assembly biases the motor assembly in the operating position and allows the motor assembly to move toward the locking position when either a predetermined force overcomes a biasing force or when the barrier is moved to a closed limit position or when forced entry is imposed on the barrier. The biasing force may be adjusted by moving posts on the motor assembly that are engaged by the bias assembly. A disengagement feature may also be provided that allows pivotable movement of the motor assembly even when in a locking position. And the pivoting motor assembly may be used as a secondary entrapment input to an operator controller.
    Type: Grant
    Filed: February 16, 2006
    Date of Patent: October 16, 2007
    Assignee: Wayne-Dalton Corp.
    Inventors: Willis J. Mullet, Paul J. VanDrunen
  • Patent number: 7262959
    Abstract: An apparatus for housing a drawer-type storage unit including a storage unit that stores data and a case in which the storage unit is contained in a drawable manner includes a drawing-status determining unit that determines whether the case is drawn from the apparatus; and a fan controlling unit that controls a revolutions-per-minute of a fan provided in the apparatus based on a result of determination by the determining unit.
    Type: Grant
    Filed: August 22, 2005
    Date of Patent: August 28, 2007
    Assignee: Fujitsu Limited
    Inventor: Tomoya Makino
  • Patent number: 7183731
    Abstract: A method of generating pulses includes setting a cycle based on a frequency of reference clock, determining a total number of the pulses to be generated during the cycle, calculating the number of one or more first reference clocks used to determine a width of one or more first pulses, the number of one or more second reference clocks used to determine a width of one or more second pulses, a first pulse number for the first pulses and a second pulse number for the second pulses on the basis of the cycle and the total number of the pulses, and generating the first pulse number of the first pulse and the second pulse number of the second pulses during the cycle. A motor control system employs the above pulse generating method and a pulse generator using the method to improve accuracy of controllability of a motor by generating the total number of the pulses during a cycle, and decrease a manufacturing cost.
    Type: Grant
    Filed: October 18, 2004
    Date of Patent: February 27, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: In-su Yang
  • Patent number: 7180257
    Abstract: A system and method is provided for improved monitoring and controlling of mechanically commutated DC motors. The system and method include DC motors, pulse-count driver circuitry for driving the motors, motor position sensing circuitry, and motor control circuitry. The system and method provide for improved motor current waveform sensing that is able to effectively reject false brake pulses, avoid erroneous processing due to fluctuating battery voltage levels, and reduce the sensitivity to variations in motor current signals due to dynamic motor load, manufacturing variation, system aging, temperature, brush bounce, EMI, and other factors. The system and method also include an improved ability to multiplex additional external motor drivers to the motor control circuitry, select between sequential and simultaneous drive modes using an SPI bit, and monitor the system controller for an error condition and simultaneously driver motors in response to the error condition.
    Type: Grant
    Filed: February 27, 2006
    Date of Patent: February 20, 2007
    Assignee: Delphi Technologies, Inc.
    Inventors: Philip K. Schneider, David D. Moller
  • Patent number: 7170251
    Abstract: A diagnostic system is disclosed for analyzing a limited rotation motor system. The diagnostic system includes a first transform unit, a second transform unit, a closed loop frequency response unit, and a diagnostic system. The first transform unit is for receiving a first digital signal that is representative of a motor control signal, and is for providing a motor control frequency domain signal that is representative of a frequency domain representation of the motor control signal. The second transform unit is for receiving a second digital signal that is representative of a position detection signal, and is for providing a position detection frequency domain signal that is representative of a frequency domain representation of the position detection signal. The closed loop frequency response unit is for identifying a representation of the frequency response of the limited rotation motor responsive to the position detection frequency domain signal and the motor control frequency domain signals.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: January 30, 2007
    Assignee: GSI Group Corporation
    Inventor: Yuhong Huang
  • Patent number: 7164244
    Abstract: An electric motor controller controls the currents flowing through the phase windings of an electric motor. The electric motor controller includes driving stages for driving respective phase windings of the motor and a memory for storing samples of reference signals. The driving stages force currents corresponding to the reference signals through a respective phase winding of the motor. The electric motor controller includes circuitry to determine subdivision degree intervals of an electric rotation and circuitry for comparing one of the currents flowing through the respective phase windings of the motor with at least one of the samples of the respective reference signal in at least one portion of each one of the degree intervals.
    Type: Grant
    Filed: December 1, 2004
    Date of Patent: January 16, 2007
    Assignee: STMicroelectronics S.R.L.
    Inventor: Marco Viti
  • Patent number: 7148647
    Abstract: An analog amplifier performs control of a motor at the speed in proportion to a speed instruction (analog voltage) outputted from a numerical control device. The speed instruction (analog value) is converted into a digital value by an A/D converter and is then sent to a CPU. When the CPU judges that the received digital value corresponding to the speed instruction deviates from a predetermined range, the CPU stops sending out an enable signal, and sends out an emergency stop signal. As a result, the CPU stops electric power supply to the analog amplifier, and also invalidates the speed instruction sent to the analog amplifier 20, thereby performing control to make the speed of the motor become “0”.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: December 12, 2006
    Assignee: Fanuc Ltd
    Inventors: Kazunari Aoyama, Kunitaka Komaki, Yasuharu Aizawa
  • Patent number: 7135831
    Abstract: A motor control method is provided in which a cycle between at least one of leading edges and trailing edges of a pulse signal is measured. The pulse signal is outputted from a pulse signal generator which generates a pulse signal every time a driven target is driven for a specified distance by a motor. A driving velocity of the driven target is calculated from the measured edge cycle. A manipulated variable of the motor is calculated such that the calculated driving velocity corresponds to a specified target velocity, and the motor is driven and controlled based on the manipulated variable. The driving velocity is replaced with a specified set velocity that is lower than the target velocity, when no output of edges from the pulse signal generator continues for and over a specified replacement determination time while the motor is driven and controlled.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: November 14, 2006
    Assignee: Brother Kogyo Kabashiki Kaisha
    Inventor: Shigeki Akiyama
  • Patent number: 7103448
    Abstract: A robot system capable of performing automatic updating of data inherent to a robot mechanism section or a mechanical unit thereof when changing the robot mechanism section or the mechanical unit. After changing the robot mechanism section or the mechanical unit, data of identifiers are read by a robot control section from nonvolatile memories associated with encoders in the robot mechanism section or the mechanical unit automatically upon turning-on of a power supply on or a manual operation. If it is determined that a kind of the robot is changed, the data indicating the kind of robot is rewritten in the robot control section. If it is required to change an algorithm for forward/inverse transformation for calculation of a robot locus, the algorithm is changed. If a kind of the robot is not changed, it is determined whether individuality of the whole robot mechanism section or the mechanical unit is changed or not.
    Type: Grant
    Filed: October 29, 2003
    Date of Patent: September 5, 2006
    Assignee: Fanuc LTD
    Inventors: Tetsuaki Kato, Yukinobu Tsuchida, Makoto Someya
  • Patent number: 7062159
    Abstract: A device for correcting a digital estimate of an electric signal is described. The device includes a comparator that generates a current proportional to the difference between an analog estimate signal, which derives from the digital estimate, and the electric signal. The device also includes a capacitor positioned to be charged by the current, a transistor that discharges the capacitor, and a comparator that compares the voltage at the terminal of the capacitor with a reference voltage. The device also includes a controller that drives the transistor in response to the output signal of the comparator and a logic device that generates a correction digital signal to be added to or subtracted from the digital estimate of the electric signal in correspondence of an ascending or descending waveform of the electric signal.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: June 13, 2006
    Assignee: STMicroelectronics S.r.l.
    Inventors: Antonio Borrello, Stefano Saggini, Aldo Novelli, Ignazio Bellomo
  • Patent number: 7057364
    Abstract: An actuating system having an electric motor that is controlled by a computer as a function of a setpoint position of a member that is to be actuated. The actuating system includes an encoder that is dependent on the movement of the motor, a sensor designed to deliver two square digital position signals in quadrature and which are representative of the position of the encoder, a device for processing the signals and which can determine the actual position of the encoder, and a device for comparing the actual position of the encoder with the position of the encoder that corresponds, in theory, to the applied setpoint. The actuating system can be used to actuate a member and/or actuate a device that meters the amount of fuel provided to a heat engine.
    Type: Grant
    Filed: December 4, 2003
    Date of Patent: June 6, 2006
    Assignee: S.N.R. Roulements
    Inventors: Gérard Ballas, Christophe Nicot
  • Patent number: 7049778
    Abstract: An interrupt signal is generated at each of rising timings of PWM signals which are produced on the basis of phase-shifted triangular wave carrier signals for phases, and voltage command values for the phases. At timings of the interrupt signals, A/D conversion of motor currents of the phases detected by a shunt is started. Interrupt signals are also produced at timings of valleys of the triangular wave carrier signals. Additionally, peak interrupt signals and valley interrupt signals are respectively produced at timings of peaks and valleys of triangular wave carrier signals for phases. Based on each of the peak interrupt signals, normality/abnormality of a switching element of an upper side of the phase corresponding to the interrupt signal is checked, and, based on each of the valley interrupt signals, normality/abnormality of a switching element of a lower side of the phase corresponding to the interrupt signal is checked.
    Type: Grant
    Filed: February 9, 2005
    Date of Patent: May 23, 2006
    Assignee: Nippon Yusoki Co., Ltd.
    Inventor: Ikuya Katanaya
  • Patent number: 7012397
    Abstract: In a control apparatus, a “characteristic value calculation” block calculates a characteristic value (such as amplitude value, offset value, or waveform distortion for each phase of two-phase sinusoidal signals optically input from an encoder, or phase difference between the two phase signals) for each of the two-phase sinusoidal signals, and an “alarm detection” block checks the presence or absence of an excursion outside a predetermined allowable range and, if such an excursion is detected, produces an alarm indication or the like. Each time the “present characteristic value” is input, a “characteristic value comparison” block compares it with “previous characteristic values”, and analyzes the result of the comparison. That is, the difference between the present value and each previous data is calculated, and the largest amount of variation (with plus or minus sign) is obtained; if this amount is larger than a predetermined value, a signal indicating an “imminent failure” is output.
    Type: Grant
    Filed: February 18, 2005
    Date of Patent: March 14, 2006
    Assignee: Fanuc LTD
    Inventors: Mitsuyuki Taniguchi, Keisuke Imai, Ichirou Nagatomo, Shinichi Horikoshi, Takashi Harada
  • Patent number: 6998810
    Abstract: A position controller for controlling a position of a feed shaft of a machine having a motor and the feed shaft driven by the motor is provided. A subtractor calculates a difference between a speed instruction and a speed detection value of a motor and outputs as a speed difference. An adder 20 adds the speed difference and a speed instruction compensation value and a speed difference proportion calculator calculates a proportional component of the speed difference based on the added result and a proportional gain. A speed difference integral calculator calculates an integral component of the speed difference based on the speed difference and an integral gain. An adder 6 adds the proportional component of the speed difference and the integral component of the speed difference to output a torque instruction.
    Type: Grant
    Filed: September 3, 2004
    Date of Patent: February 14, 2006
    Assignee: Okuma Corporation
    Inventor: Tomohisa Kameyama
  • Patent number: 6995538
    Abstract: A region judging circuit judges an electric angle region of a three-phase brushless DC motor based on an output signal of a resolver. A latch timing output circuit determines an optimum latch timing. A driving direction judging circuit judges a rotational direction of the motor based on a comparison in largeness between a pair of phase currents. A latch circuit latches a judgement result of the driving direction judging circuit at the latch timing designated by the latch timing output circuit and retains the judgement result until the next latch timing comes.
    Type: Grant
    Filed: February 3, 2003
    Date of Patent: February 7, 2006
    Assignee: Denso Corporation
    Inventor: Yoshitaka Hayashi
  • Patent number: 6967459
    Abstract: The invention concerns a method of regulating the current in a direct current machine with which are associated an arrangement for generating a current target value signal, as well as a PWM generator (FIG.
    Type: Grant
    Filed: August 14, 2001
    Date of Patent: November 22, 2005
    Assignee: ebm-papst St. Georgen GmbH & Co. KG
    Inventors: Alexander Hahn, Hermann Rappenecker
  • Patent number: 6949900
    Abstract: A processor for controlling a sensorless, brushless DC motor is disclosed comprising a first output for providing a control signal to a potentiometer controlling the speed and voltage of the DC motor. The processor also includes a second input for receiving a back-EMF voltage from an open phase of a three phase winding. The processor determines a digital error signal from the back-EMF voltage and generates a control signal responsive to the digital error signal. The control signal decreases the speed of the motor when the digital error signal is in a first range. The processor decreases both the speed and voltage of the motor when the digital error signal is in a second range. The processor increases the speed of the motor when the digital error signal is in a third range. The processor increases both the speed and voltage of the motor when the digital error signal is in a fourth range.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: September 27, 2005
    Assignee: Silicon Laboratories Inc.
    Inventor: Kenneth Alan Berringer
  • Patent number: 6912427
    Abstract: A programmable limit switch includes output channels for receiving position data, each position value of the position data representing an incremental advance of a workpiece through a production field, and for producing actuation signals. The channels are connectable to respective output devices responsive to the respective actuation signals and located in the field. Each output channel has an output controller, which is individually programmable to change the state of respective actuation signals in response to reaching selected position values. Preferably, the PLS includes input connectors coupled to a respective channel and connectable to respective input devices located within the production field. Each channel operates its own inputs and outputs according to a variety of programmed functions depending upon system conditions seen by the output controller.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: June 28, 2005
    Assignee: Ametek, Inc.
    Inventors: Jack Pattee, Sheila F. Champagne
  • Patent number: 6894453
    Abstract: One embodiment of the present invention is an apparatus to provide a measure of disk drive head velocity in a disk drive wherein movement is produced by a disk drive motion mechanism that includes a coil, which apparatus includes: (a) a controller that outputs one or more digital signals that are applied as input to a first component, and in response, the first component outputs a reference voltage; (b) a second component, responsive to voltage output across the coil and the reference voltage, outputs a measure of a difference between the coil voltage and the reference voltage; and (c) a third component, responsive to the measure of the difference, outputs a first value if the coil voltage is greater than the reference voltage and a second value if the coil voltage is less than the reference voltage, which third component output is applied as input to the controller; wherein the controller executes a search algorithm that varies the one or more digital signals while observing changes in the third component ou
    Type: Grant
    Filed: October 16, 2003
    Date of Patent: May 17, 2005
    Assignee: Riospring, Inc.
    Inventors: David M. Drouin, Avraham Perahia
  • Patent number: 6876891
    Abstract: A method and apparatus implementing a user interface device, such as a mouse or trackball, having electronically controllable tactile responsiveness which is flexibly programmable. A user interface device effects positioning of a cursor within a limited area, such as on a display screen, with limits imposed by controllable tactile responsiveness. Programmable force-position characteristics relate the tactile responsiveness of the interface device to the position of the cursor within the limited area or on the display screen. In a described embodiment, the interface device includes at least two sets of wheels that move as the interface device is actuated. The at least two sets of wheels are aligned on mutually orthogonal axes. A servo motor is attached to each of the at least two sets of wheels.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: April 5, 2005
    Assignee: Immersion Corporation
    Inventors: Chester L. Schuler, Seth M. Haberman
  • Patent number: 6822414
    Abstract: A motor controller capable of obtaining information on offsets, amplitudes and a phase difference of analog feedback signals from encoders without using special measuring device. The analog feedback signals from the encoders are A/D converted and the offsets, the amplitudes and the phase difference of A-phase and B-phase analog feedback signals are obtained based on the converted digital signals by an arithmetic section. The obtained offsets, amplitudes and phase difference are displayed by a display section of the motor controller and/or a display section of a numerical controller as a host controller. Further, the obtained offsets and amplitudes are compared with respective reference values for determining acceptability of the feedback signals from the encoders and the results of the comparison is displayed by the display section and/or the display section of the numerical controller.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: November 23, 2004
    Assignee: Fanuc Ltd.
    Inventors: Yuuki Morita, Shinichi Kono, Takahiro Akiyama
  • Patent number: 6707269
    Abstract: Method and apparatus for controlling a motor. A digital to analog converter (DAC) converts input digital values to corresponding analog voltages over a range of different selectable dynamic operating ranges. A first motor adjustment signal within a first dynamic range of the DAC is generated in relation to a velocity error of the motor, and applied to the DAC to control flow of current through the motor. The DAC is adjusted to a different, second dynamic range when the first motor adjustment signal is proximate an upper end or a lower end of the first dynamic range. Expanding the dynamic range allows greater amounts of current to be applied to the motor; contracting the dynamic range provides higher resolution (volts/count) and greater stability. The different ranges are automatically selected for different motor load conditions.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: March 16, 2004
    Assignee: Seagate Technology LLC
    Inventor: Triet M. Tieu
  • Publication number: 20030150412
    Abstract: The operational state of the engine is detected and the target value of the motor is computed corresponding to the operational state (step S1); a current value of the motor is obtained (step S2); and the width of a stop target area that is a determination parameter is selected based on the target value and the current value (step S3). The stop target area is obtained based on the selected width of the stop target area and the target value (step S4). If the current value falls within the stop target area, then a motor control signal is determined so as to maintain the current value, and if the current value is beyond the stop target area, then the motor control signal is determined so as to draw the current value toward the target value (steps S6 and S7).
    Type: Application
    Filed: November 5, 2002
    Publication date: August 14, 2003
    Applicant: MITSUBISHI DENKI KABUSHIKI KAISHA
    Inventor: Manabu Gohou
  • Patent number: 6445961
    Abstract: A multi-purpose controller for variables which closely controls such variables to set point by making sequential corrections to the level of input to the system of the variable based on: system response time, relationship of controller output to the variable, deviation of the variable from set point, and change in system load as determined by change in error and change in system input. The controller has a self tuning capability and can provide generation of the set point according to a set of variable parameters. It can be configured as a stand alone controller, as an intelligent Input/Output device for another intelligent device, or be resident in another intelligent device such as a programmable controller, computer or other microprocessor based device.
    Type: Grant
    Filed: March 7, 2000
    Date of Patent: September 3, 2002
    Inventor: Kenneth P. Melvin
  • Patent number: 6445966
    Abstract: An data interface module is provided for allowing a user to remotely modify a predetermined number of operating parameters of a motor driven by a motor control and for displaying the same. The interface module includes a micro-controller interconnected to a communications network and a visual display structure. The visual display structure has a first screen which displays a scrollable list of the operating parameters and a second screen which displays a data value for a user selected one of the operating parameters. A user may modify the user selected operating parameter when the second screen is displayed.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: September 3, 2002
    Assignee: Eaton Corporation
    Inventors: Charles T. Younger, Thomas M. Ruchti, Erik W. Linske
  • Patent number: 6429618
    Abstract: The index signal generator generates an original signal every the rotor of the direct-drive motor rotates, and delays the original signal by a delay time to produce index signal. The index signal generator comprises, as the delay giving the delay time, the delay counter that can be set the initial value, instead of an analog delay circuit, a variable register and a capacitor. The delay counter comprises the counter and the counter value selector for determining the initial value of the counter. The counter starts to count the clock signals generated by the clock in response to the original signal, and stops counting the clock signals and generates the index signal when the number of the clock signals counted by the counter reaches the initial value.
    Type: Grant
    Filed: December 28, 2000
    Date of Patent: August 6, 2002
    Assignee: Mitsumi Electric Co., Ltd.
    Inventors: Akira Shibata, Yoshihito Otomo
  • Publication number: 20020024314
    Abstract: A voltage regulator of a vehicle AC generator includes a control circuit connected to a power circuit for supplying field current to a field coil of the AC generator, a power circuit for supplying electric power to the control circuit, a power drive circuit for controlling the power circuit according to a self-excited voltage induced in an armature coil of the AC generator, and a bypass circuit connected to a ground. The resistance of the bypass circuit is reduced when the power circuit does not supply electric power to the control circuit and is increased when the power circuit supplies electric power to the control circuit. Therefore, power consumption of the bypass circuit is reduced when the AC generator starts regular power generation.
    Type: Application
    Filed: June 26, 2001
    Publication date: February 28, 2002
    Inventors: Keiji Takahashi, Toshinori Maruyama, Makoto Taniguchi
  • Publication number: 20020021100
    Abstract: An apparatus for producing a floating DC voltage source from an electric motor which may be a brushless DC motor. The apparatus includes a rectifier circuit for rectifying back electromotive force voltage from a winding of the motor and a clamping circuit for clamping the rectified voltage to produce a floating DC voltage which may be a TTL logic level voltage. A motor control circuit is disconnected from the winding to produce the back electromotive force voltage.
    Type: Application
    Filed: August 16, 2001
    Publication date: February 21, 2002
    Inventor: Fred A. Brown
  • Patent number: 6333613
    Abstract: A servo system controller in which motor specification data inputted through a CRT/keyboard (1) and representing the characteristics of a motor is edited into electronic cam data by a data editing section (22), the edited data is displayed in the form of a table or graph, such as a cam diagram, on a data display section (25), and the electronic cam data converted into the one of a format enabling cam motion is generated by a machine drive section and stored, comprising input data calculating means (26) for calculating the acceleration/deceleration peak torques and the rotational speed of a motor for every block of the electronic cam data, a motor specification data table (28) stored with the known motor specification data, and input judging means (27) for displaying the result of the comparison of the output of the input data calculating section (26) with the motor specification data for every block on a display section.
    Type: Grant
    Filed: November 17, 2000
    Date of Patent: December 25, 2001
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Kanji Watanabe, Ikuo Nagamatsu
  • Patent number: 6323614
    Abstract: A system for controlling the position of a rotating member suspended using a magnetic field includes at least one sensor that is operable to detect the position of the rotating member, the sensor further being operable to generate a position reference signal in response to the detected position. The system also includes a controller in communication with the at least one sensor and being operable to generate an actuator control signal in response to receiving the position reference signal. The controller is operable to introduce a phase lead in the actuator control signal in response to a rotational speed of the rotating member. The system further includes at least one actuator in communication with the controller that is operable to adjust the position of the rotating member in response to the actuator control signal by modifying characteristics of the magnetic field.
    Type: Grant
    Filed: September 3, 1999
    Date of Patent: November 27, 2001
    Assignee: The Texas A&M University System
    Inventors: Alan Palazzolo, Mu Li, Uhn Joo Na, Erwin Thomas
  • Patent number: 6294910
    Abstract: A moving target opposite a stationary analog sensor has two sensitive elements delivering two sinusoidal output signals, of equal maximum amplitudes, centered on the same average value, in quadrature and with a period equal to one revolution of the target. A device for processing the two output signals, generates n output signals in-parallel, where n is a positive whole number greater than or equal to 2, for providing the position of a rotating component, connected to the moving target, with a resolution equal to 2n. The processing device includes a generator device, a detection device, a multiplexing device and an interpolation device.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: September 25, 2001
    Assignee: The Torrington Company
    Inventors: Francis Travostino, Alain Bochet