Pulse Or Frequency Counter Patents (Class 388/912)
  • Patent number: 8928271
    Abstract: An apparatus or method which accepts a burst of pulses at a frequency which may not be tightly controlled and converts this into a trajectory command that is a suitable motion profile for an incremental motor control application. The output of the invention can be a pulse stream that can be fed to an existing incremental pulse input motor drive or the invention can be embedded into a motor drive where its output is a numerical sequence that defines a physically realizable trajectory to be fed to the control circuits and software within the motor drive.
    Type: Grant
    Filed: March 8, 2013
    Date of Patent: January 6, 2015
    Assignee: Teknic, Inc.
    Inventors: Thomas John Bucella, David W. Sewhuk, Scott M. Mayne
  • Patent number: 8598833
    Abstract: An electronically commutated motor (ECM) includes windings, a power switch, an infrared transceiver and an electromagnetic shield. The power switch is configured to provide pulse width modulated (PWM) power signals to the windings and to generate a substantial level of electromagnetic noises at PWM frequencies during its switching operation. The infrared transceiver is configured to communicate with an external device using infrared signals and convert electrical signals from and to infrared signals that carry data. The electromagnetic shield is configured to substantially shield the infrared transceiver from the electromagnetic noises of PWM frequencies from the power switch.
    Type: Grant
    Filed: December 13, 2010
    Date of Patent: December 3, 2013
    Assignee: Sntech Inc.
    Inventor: Young Chun Jeung
  • Patent number: 8562304
    Abstract: An electrical motor activation method for an electric motor including a rotor, connected to a motor shaft, and a stator having brushes. The stator comprises multiple commutator laminations for the commutation of windings disposed on the rotor and is activated by a pulsed or linearly controllable power source. The motor shaft is connected to a radially driven load, in particular a pump, which has a nonlinear torque curve via a motor revolution. A waviness signal is obtained from a voltage potential applied to the motor and/or from the motor current and rotor position information is obtained from the curve of said waviness signal.
    Type: Grant
    Filed: March 9, 2009
    Date of Patent: October 22, 2013
    Assignee: Continental Teves AG & Co. oHG
    Inventors: Dieter Barthel, Ralf Hartmann, Andreas Heise, Christian Bitsch, Daniel Schmitz, Andreas Richter
  • 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: 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: 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: 6983102
    Abstract: When a signal level of a motor brush switching signal is low and thus dropouts or omission of the pulse signals converted by a waveform shaping part take place, so that an interval between a pulse signal to be currently counted and an immediately preceding pulse signal thereof becomes longer than a predetermined average interval, a pulse signal counter makes a correction of the number of counts by adding one pulse to the pulse to be counted. Therefore, even if the signal level of the motor brush switching signals generated from a vertical motion motor M2 is low for some reasons, accurate control can be exercised over the number of rotations of the vertical motion motor M2.
    Type: Grant
    Filed: September 16, 2003
    Date of Patent: January 3, 2006
    Assignee: Murakami Corporation
    Inventors: Ayako Yamada, Akiyoshi Kobayashi, Mitsuyoshi Nagao
  • Patent number: 6819074
    Abstract: An apparatus for controlling a driving speed of a motor comprises a motor controller provided in the motor controlling apparatus detecting the motor driving speed in response to pulses outputted from an encoder. The motor controller adjusts a detection period for the pulses according to the motor driving speed, thereby measuring the motor driving speed. The motor controller sets the detection period so that a number of four-multiplied pulses can be a multiple of four. Although a phase difference between pulses outputted from an encoder is not constant, the motor controlling apparatus can obtain a desired response characteristic by excluding effects of a phase error between the pulses.
    Type: Grant
    Filed: December 31, 2002
    Date of Patent: November 16, 2004
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Ho-Sun Yoo
  • Patent number: 6559616
    Abstract: A motor rotational pulse generating circuit for a motor is provided which generates a correct pulse signal even at an initial turning-on stage of the motor, by adjusting a filter cutoff frequency in response to motor rotational condition. The motor rotational pulse generating circuit includes a rotational pulse generation circuit 20 which generates ripple pulses based on a signal being inputted from the DC motor 1, in which a ripple is superposed whose frequency is in proportion to a rotation number of the DC motor 1. A filter 3 makes a cutoff frequency variable on the basis of a clock signal issued from a PLL circuit 6. An oscillation frequency at an oscillator VCO10 is determined by the ripple pulses and a motor rotation condition signal inputted by way of circuits 12 to 16 inclusive. A microcomputer 20 operates, when the motor is turned on, to cause the oscillator VCO10 to issue a preliminary clock signal.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: May 6, 2003
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventors: Koji Aoki, Nobuyasu Kimura, Hideyuki Kanie, Hitoshi Ishikawa
  • Patent number: 6400113
    Abstract: Apparatus for monitoring fan speeds within a computing system includes a tachometer turning with the fan, providing a tachometer signal including a number of pulses during each revolution of the fan. This tachometer signal is provided as an input to a signal generator in the form of a flip-flop, which generates a square-wave signal having transitions between high and low levels corresponding to tachometer signal pulses. The square-wave signals are provided as inputs to separate input ports of a microprocessor. These input ports are sequentially sampled at a rate providing at least two samples per period of the fastest square-wave signal, so that transitions of each square wave signal during a predetermined time interval can be detected and counted. For each input port, the number of counted transitions is compared to a stored acceptable value to establish whether the fan is operating in an acceptable speed range.
    Type: Grant
    Filed: July 19, 2000
    Date of Patent: June 4, 2002
    Assignee: International Business Machines Corporation
    Inventors: Ray Garcia, Will E. Hamel, Kendall A. Honeycutt, Stephen E. Still
  • Publication number: 20020045953
    Abstract: A function selecting control system is provided, which modularizes a plurality of wiper control systems, builds them in an integrated circuit, and selects a desired system on the basis of a selection signal of the system from the outside, thereby drive-controlling a wiper motor. The function selecting control system includes: input means 30a for inputting a selection signal which selects a control logic block 30h corresponding to a starting control mode out of the control logic blocks provided for every control mode of the motor; judgment means 30c for reading the input selection signal for a standard number of times and for judging the coincidence among the read selection signals; count means 30e for counting the number of times of the coincidence; settlement means 30f for settling the selection signal when the number of times of the coincidence reaches the predetermined standard number; and system starting means 30g for starting a control logic corresponding to the settled selection signal.
    Type: Application
    Filed: October 11, 2001
    Publication date: April 18, 2002
    Inventors: Akihiko Torikoshi, Kazuhiro Kubota, Yuichi Nakazawa
  • Patent number: 6335603
    Abstract: Disclosed herein are a motor control circuits and a control system comprising the motor control circuits.
    Type: Grant
    Filed: September 1, 2000
    Date of Patent: January 1, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toru Otsuka, Takeo Hashimoto, Hiroshi Watanabe
  • Patent number: 6327425
    Abstract: A regulator for heating and air-conditioning appliances in motor vehicles, having a suction fan which is driven by an electrically commutated DC motor and in whose induction air flow a temperature measurement sensor is arranged. A disturbance in motor running which may lead to an incorrect temperature measurement is detected at an early stage by providing measurement means which, in two time intervals, determine measurements that are proportional to the frequency of the motor voltage, and compare these measurements with one another.
    Type: Grant
    Filed: March 13, 2000
    Date of Patent: December 4, 2001
    Assignee: Mannesmann VDO AG
    Inventor: Henry Strobel
  • Patent number: 6262549
    Abstract: A fan speed pulse filter is used for a PWM fan. The filter comprises a comparator, a latch circuit and a synchronizer. The fan unit, including a tachometer pulse output, is controlled by a PWM signal for determining the fan speed. By comparing the PWM signal with a reference voltage, the comparator generates a reset signal. The latch circuit, coupled to the comparator and the fan unit, receives the reset signal and the tachometer pulse and outputs a filtered tachometer pulse containing no phantom pulses. Furthermore, a synchronizer generates an output signal without interruption when the PWM signal is switched off.
    Type: Grant
    Filed: June 29, 2000
    Date of Patent: July 17, 2001
    Assignee: System General Corp.
    Inventors: Ta-yung Yang, Jenn-yu G. Lin, Cheng-chi Hsueh
  • Patent number: 6040671
    Abstract: An apparatus for controlling an actuator having a moveable member and having a coil that influences movement of the member, by provision of a drive current to the coil in response to a target speed voltage signal. The invention includes an up/down counter, counting at a predetermined count rate and providing a count output. A control unit is provided for controlling the direction of count of the up/down counter depending on whether the voltage across the coil, sensed periodically a first predetermined interval after the drive current to the coil is interrupted, is greater than, or less than, a reference voltage having a predetermined relationship to the target speed voltage. A digital-to-analog converter is provided, responsive to the count output to provide a compensated voltage signal having a voltage corresponding to the count output.
    Type: Grant
    Filed: January 28, 1999
    Date of Patent: March 21, 2000
    Assignee: Texas Instruments Incorporated
    Inventors: Joao Carlos F. Brito, John K. Rote, Frederick W. Trafton, Marcus M. Martins
  • Patent number: 5798919
    Abstract: In a technique of monitoring whether a physical system is normal or abnormal by continuously comparing a phenomenon taking place in the system and a phenomenon taking place in a model and also in a technique of control adopting evaluation functions using an error quantity in the model, the phenomena in both the physical system and model can be optimized. An equivalent electric circuit to the physical system is produced, and an input is provided to both of the system and the circuit. In this state, the output of the physical system and the reference value of the equivalent electric circuit are compared. The use of the equivalent electric circuit permits solving the problem inherent in the prior art that the time necessary for analog-to-digital conversion and numerical calculations is longer than the time of the actual phenomenon and disables real time simulation.
    Type: Grant
    Filed: March 5, 1996
    Date of Patent: August 25, 1998
    Assignees: Toyota Jidosha Kabushiki Kaisha, Toyota School Foundation
    Inventors: Kazutsugu Suita, Yoji Yamada, Nuio Tsuchida, Koji Imai
  • Patent number: 5790971
    Abstract: A frequency-locked stepping position control servo (FLSPS) system for driving a stepping motor. It essentially comprises a means for driving the stepping motor to move an object toward a target according to a driving signal, a means for detecting position of the object, a position-to-frequency converter to feedback the position information and a microprocessor-based slope-varied frequency-controlled oscillator (.mu.P-SVFCO) to generate the driving frequency. The .mu.P-SVFCO includes a microprocessor to ease the implementation of the control law and utilizes the slope-varied technique to adaptively pump the pulse train frequency of the driving signal. In addition, a one-bit clock is provided to dynamically maintain the position of the object when the target position is reached. The FLSPS system is capable of achieving similar system acquisition times for different target commands among a wide-range of positioning control commands.
    Type: Grant
    Filed: June 19, 1996
    Date of Patent: August 4, 1998
    Assignee: National Science Council
    Inventor: Guan-Chyun Hsieh
  • Patent number: 5696642
    Abstract: A circuit for controlling a rotating member is provided with an input capture register which reads out the value of a free running counter at a timing of an FG (frequency generated) pulse generated in accordance with a rotation of a rotating member. A central processing unit performs an interrupt operation based on a PG (phase generated) pulse generated in accordance with a rotation of the rotating member and an interrupt operation based on the FG pulse. A pulse width modulation circuit rotates the rotating member by use of a speed error signal and a phase error signal which are obtained by the interrupt operations of the central processing unit. A rotating member driver is also provided. The central processing unit calculates the phase error signal from an output of the input capture register based on an FG pulse generated after the generation of the PG pulse.
    Type: Grant
    Filed: December 8, 1994
    Date of Patent: December 9, 1997
    Assignee: Rohm Co., Ltd.
    Inventors: Yo Sawamura, Toshihiro Tafuru
  • Patent number: 5680023
    Abstract: A method of measuring a linear velocity of a rotating disk on a disk drive system wherein a rotation of a spindle motor is controlled in accordance with a predetermined linear velocity which is generated based on a signal reproduced from the disk to control the initial rotation of the spindle motor. The linear velocity of the disk is determined by measuring one revolution of the disk and from the radius of the disk. The disk drive system includes a servo control system to measure the one revolution of the disk and to generate a servo control signal at a time corresponding to a predetermined number of output pulses from the spindle motor measured during the one revolution time of the disk. The servo control signal is supplied to the spindle motor to control its initial rotation.
    Type: Grant
    Filed: May 18, 1995
    Date of Patent: October 21, 1997
    Assignee: Mitsumi Electric Co., Ltd.
    Inventor: Tatsuya Komaki
  • Patent number: 5548679
    Abstract: A PLL system has a phase comparator for converting the phase difference between a reference clock signal and a feedback clock signal corresponding to a PWM signal Into a binary value, a frequency comparator for converting the frequency difference between the reference and feedback clock signals into a binary value, an automatic gain controller for adjusting the loop gain of the PLL system to a given value whenever the output of the frequency comparator reaches a change point, and a PWM signal generator for generating the PWM signal according to the outputs of the phase comparator, frequency comparator, and automatic gain controller. These components of the PLL system process digital signals, to simplify the structure of the PLL system, expand the range of loop gains to be set, and speedily synchronize the feedback clock signal with the reference clock signal.
    Type: Grant
    Filed: February 10, 1995
    Date of Patent: August 20, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shinichi Kiyota
  • Patent number: 5483132
    Abstract: A control device for an electrically driven telescopic antenna including: a counting signal extracting circuit which detects the altered waveform of an rectified current generated during the forward or reverse rotation of a DC motor so as to extract counting signals; a command device which sends a control stop command to a motor drive control circuit when the counted value of the extracted counting signals reaches a certain preset value; a motor current monitoring circuit which monitors the current flow to the motor and outputs information on the completion of the antenna element extension/retraction action when the motor current value exceeds a prescribed value; and a correction device which corrects the counted value based upon the information outputted by the motor current monitoring circuit. The control device can include a large-capacitance capacitor for absorbing power supply fluctuations.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: January 9, 1996
    Assignee: Harada Kogyo Kabushiki Kaisha
    Inventors: Koji Arata, Kazufumi Sato, Yuji Maeda
  • Patent number: 5387856
    Abstract: In a speed control arrangement for an induction motor or an a.c. permanent magnet motor in which any one of a number of power frequencies may be selected for application to the motor, there is provided circuitry to control the rate of change of frequency from one selected power frequency to another to control the acceleration or deceleration of the motor.
    Type: Grant
    Filed: October 20, 1993
    Date of Patent: February 7, 1995
    Assignee: Plessey SemiConductors Limited
    Inventor: David P. Gilbert
  • Patent number: 5365385
    Abstract: In the spindle control system of the present invention the compensator is divided into two portions. The first portion is driven by a first clock signal at a first frequency and a second portion is driven by a second clock signal at a second frequency derived from the first clock signal. In particular, the integrator utilizes a clock which increases the time measurement to be a longer interval than the measurement utilized for the remainder of the compensator circuit. This allows the absolute speed to be adjusted with a high resolution independent of the gain. Therefore, the gain can be maintained and the loop dynamics are preserved, maintaining dynamic range and stabilization while increasing the resolution of control of the spin speed.
    Type: Grant
    Filed: June 24, 1993
    Date of Patent: November 15, 1994
    Assignee: Maxtor Corporation
    Inventors: James W. Hargarten, Steven P. Ward
  • Patent number: 5345532
    Abstract: A rotation drive device for driving a rotator is disclosed, comprising an electric motor for driving the rotator, a phase detecting circuit for detecting the phase of rotation of the rotator, a reference signal source for forming a reference signal of a constant period, a phase control circuit for controlling the motor in such a manner that the phase difference between the output of the reference signal source and the output of the phase detecting circuit becomes a constant value, a detecting circuit for detecting a fact that the reading-out of the phase difference is not completed in the time interval between the successive two outputs of the phase detecting circuit, a control circuit for varying the number of cycles of phase difference computing operation of the phase control circuit depending on the time interval between the successive two outputs of the phase detecting circuit, another detecting circuit for detecting a fact that the phase detecting circuit has produced no output in one period of the refer
    Type: Grant
    Filed: September 14, 1993
    Date of Patent: September 6, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventor: Nobuo Fukushima
  • Patent number: 5293445
    Abstract: A circuit automatically changes the gain in a PLL for driving a motor of the type having a motor speed signal that indicates the speed of motor rotation. The circuit includes a phase detector for sensing a phase difference between the motor speed signal and a reference frequency and for producing an output signal of duration proportional to the sensed phase difference. A counter counts clock pulses throughout the duration of the output signal, and a motor driving circuit drives the motor in response to the count reached by the counter. A source of clock pulses provides clock signals at first and second frequencies, the second frequency being lower than the first frequency, and a lock range sense circuit produces a sense signal output that indicates when the PLL is within a predetermined phase difference range.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: March 8, 1994
    Assignee: SGS-Thomson Microelecetronics, Inc.
    Inventor: Francesco Carobolante
  • Patent number: 5278935
    Abstract: A control device for a moving body such as a focusing lens or the like is arranged to vary time intervals at which a speed control action is performed on a motor according to a driving amount required for moving the moving body to a target position by means of the motor. The arrangement enables the device to prevent an adverse effect of vibrations, etc. and to accurately accomplish position control.
    Type: Grant
    Filed: March 26, 1992
    Date of Patent: January 11, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventor: Etsuro Furutsu
  • Patent number: 5212434
    Abstract: A speed controller is equipped to a step motor for controlling the rotation of the step motor with a desired angular velocity. The step motor speed controller utilizes a phase-locked stepping servomechanism (PLSS) in which a phase-controlled oscillator (PCO) comprised of an adaptive digital-pumped controller (ADPC) and a voltage-controller oscillator (VCO) is employed. The step motor speed controller utilizes a tachometer comprised of an optical encoder for detecting the angular speed of the step motor. The tachometer sends out a first pulse train with the frequency thereof indicating the angular velocity of the step motor as a feedback signal to the ADPC. A reference signal source is employed for sending a second pulse train to the ADPC. The ADPC compares the phase difference between the first pulse train and the second pulse train and whereby a signal corresponding the phase difference is sent to the VCO, causing the VCO to output a third pulse train to the step motor.
    Type: Grant
    Filed: March 17, 1992
    Date of Patent: May 18, 1993
    Assignee: National Science Counsil
    Inventor: Guan-Chyun Hsieh
  • Patent number: 5058191
    Abstract: A motor rotation speed control circuit fabricated in an LSI, a first counter which, after being reset by each rotation of the motor, begins counting clock pulses. Bit-outputs of the first counter are led out of the LSI package of the LSI, and are selectively connected to external input lead terminals of a plurality of gate circuits, each of which detects when the first counter has counted a number determined by sum of the input bit-outputs. One gate circuit detects a first reference count-number N.sub.a, which is smaller than a probable least count-number corresponding to, for example, a lower limit of tolerance of the motor speed, considering future possible changes of the motor speed. After being reset by a reset signal corresponding to the first refernece number N.sub.a input thereto, a second counter, preset with a second reference count-number N.sub.b, starts to count the clock pulses. The second reference count-number N.sub.b is chosen so that N.sub.a +N.sub.b =N.sub.0, N.sub.
    Type: Grant
    Filed: May 22, 1989
    Date of Patent: October 15, 1991
    Assignee: Fujitsu Limited
    Inventor: Hiroshi Tsurumi
  • Patent number: 5046123
    Abstract: An error signal detection circuit in a servo control device comprises a reference signal generation circuit for selectively generating reference signals of different periods, each having a slope which changes from a reference value at a substantially constant gradient, an error detection timing generation circuit for generating timing of detection of an error signal of an object of control, an error signal detection circuit for generating an error signal by detecting the value of a reference signal generated by the reference signal generation circuit at a timing provided by the error detection timing generation circuit, and a slope varying circuit for varying the slope of the reference signal in accordance with the period of the reference signal.
    Type: Grant
    Filed: September 1, 1988
    Date of Patent: September 3, 1991
    Assignee: Yamaha Corporation
    Inventor: Mamoru Horino
  • Patent number: 5040234
    Abstract: A circuit for generating a pulse-like timing signal driving a stepping motor which is used to drive for example a magnetic tape to run in an audio tape or video tape recording and reproducing apparatus. A rewritable memory stores output pattern data and time information for generating the timing signal. This timing signal generating circuit comprises a rewrite control circuit responsive to an operation mode instructing signal, for performing a predetermined operational processing on basic pattern data and basic time information and storing the resulting output pattern data and uniquely related time information in the rewritable memory.
    Type: Grant
    Filed: December 5, 1989
    Date of Patent: August 13, 1991
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tooru Yamamoto, Kazuharu Date, Yoshihisa Nakatoh, Shigeki Imai
  • Patent number: 4933985
    Abstract: A rotation drive device for driving a rotator is disclosed, comprising an electric motor for driving the rotator, a phase detecting circuit for detecting the phase of rotation of the rotator, a reference signal source for forming a reference signal of a constant period, a phase control circuit for controlling the motor in such a manner that the phase difference between the output of the reference signal source and the output of the phase detecting circuit becomes a constant value, a detecting circuit for detecting a fact that the reading-out of the phase difference is not completed in the time interval between the successive two outputs of the phase detecting circuit, a control circuit for varying the number of cycles of phase difference computing operation of the phase control circuit depending on the time interval between the successive two outputs of the phase detecting circuit, another detecting circuit for detecting a fact that the phase detecting circuit has produced no output in one period of the refer
    Type: Grant
    Filed: May 15, 1987
    Date of Patent: June 12, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventor: Nobuo Fukushima
  • Patent number: 4914713
    Abstract: In order to pick up in a simple manner which is reliable, and under rough operating conditions, a rotation of the rotor in a miniature motor excited by permanent magnets with magnet segments at a tangential distance with magnet segments distributed at the bore circumference of the stator, it is proposed to arrange in at least one pole gap between the magnet segment a measuring coil. A signal is induced by the pulsation of the stray field due to rotation of the rotor. The measuring coil is advantageously arranged in a non-magnetic, preferably plastic support body held between the individual poles or the magnet segments respectively.
    Type: Grant
    Filed: September 9, 1988
    Date of Patent: April 3, 1990
    Assignee: Siemens Aktiengesellschaft
    Inventors: Hans-Joachim Mueller, Werner Seuffert, Udo Winter
  • Patent number: 4887307
    Abstract: A speed control device for an electric motor having a rotation speed and driven by a power source and including components for producing a counter value from the rotation speed of the motor, components for comparing the counter value produced from the producing components with a predetermined counter value of a designated speed and producing a deviation output counter value, components for integrating the deviation output for a predetermined period of time including a first integrating circuit for multiplying the deviation output by a predetermined value and producing a resultant and a second integrating circuit for adding a predetermined value to the resultant of the first integrating circuit and producing a resultant, and components for adding said second integrating circuit resultant to the deviation output of the comparator means so as to change the deviation output resultant counter value to a time value for controlling the motor driving power source.
    Type: Grant
    Filed: March 2, 1988
    Date of Patent: December 12, 1989
    Assignee: Janome Sewing Machine Co., Ltd.
    Inventors: Akira Orii, Takashi Nakamura
  • Patent number: 4885793
    Abstract: A microcomputer (20) servo controls the rotational speed and the rotational phase of a cylinder motor (37) of a VTR in a digital manner. The microcomputer (20) generates a 10-bit digital phase error signal D.sub.PH having sufficiently low conversion gain and a 10-bit digital speed error signal D.sub.SP having sufficiently low conversion gain in response to an FG signal generated with rotation of a cylinder motor. The digital phase error signal D.sub.PH and the digital speed error signal D.sub.SP are added to each other in a digital manner in the addition ratio 1:8. In addition, the result of this addition is amplified four times in a digital manner by extracting eight lower order bits thereof and then converted into an analogue signal and supplied to the cylinder motor as a servo control signal. Thus, since the error signals are added to each other in a digital manner and then, the added signal is amplified as required, a digital servo having a large capture range can be achieved as whole.
    Type: Grant
    Filed: February 8, 1988
    Date of Patent: December 5, 1989
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Junichiro Tabuchi
  • Patent number: 4885515
    Abstract: A velocity control apparatus according to the invention is used in order to acccept feedback data, for velocity control of a servomotor or the like. The disclosed apparatus provides velocity information in the form of discrete data from a pulse coder or the like, and forms a prescribed control command by digitally processing the data in a microprocessor. In a case where the above mentioned data are sampled at a predetermined sampling rate during a processing period so as to accommodate processing by the microprocessor, a lag element results when the data are accepted within the computer as velocity information which causes an inaccuracy in servomotor control. Accordingly, a detection signal forming unit (5) processes the discrete count data as the sum of count data synchronized to the sampling rate which is the processing period subdivided into a fraction, in which fraction the denominator is an integer.
    Type: Grant
    Filed: July 28, 1988
    Date of Patent: December 5, 1989
    Assignee: Fanuc Ltd.
    Inventors: Mitsuo Kurakake, Keiji Sakamoto
  • Patent number: 4884162
    Abstract: A method and apparatus prevents the overheating of a line feed motor used in a printer. First and second timers are respectively provided to measure first and second time intervals. The second time interval includes a cessation period in which the line feed motor is not driven to allow for heat dissipation of the line feed motor. At the end of the first time interval, a determination is made as to whether the number of line feed pulses during the first time interval exceeds a predetermined limit. If the number of line feed pulses does not exceed the predetermined limit, the first time is reactivated. If the number of line feed pulses does exceed the predetermined limit, then the second timer is activated to allow for heat dissipation of the line feed motor.
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: November 28, 1989
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Toshikazu Ito, Toshiro Suemune, Katsuhiko Sato
  • Patent number: 4879754
    Abstract: The invention provides a speed controller which detects the period of an AC signal containing information of the rotational speed of a motor and controls the rotational speed based on the detected period value and a reference speed value. More particularly, the speed controller computes the amount of the deviation of the AC signal based on continuously detected period values and the reference speed value, and then stores the computed deviation amount in a memory as a correction value. Using the correction value stored in the memory, the speed controller corrects the deviation of the period, and thus, the speed of the rotation of the motor can be controlled with extremely high precision.
    Type: Grant
    Filed: March 14, 1989
    Date of Patent: November 7, 1989
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kunihira Tadashi, Hiroshi Minakuchi
  • Patent number: 4873473
    Abstract: An apparatus for controlling a motor comprises an oscillator for providing a source of periodic signals, and a divider for converting the oscillator output into desired motor rotation frequency signals. A tachometer generates actual motor rotation frequency signals and a comparator compares the actual and desired motor rotation frequency signals and generates a rotation frequency error signal. The tachometer and the divider are coupled to the comparator. An SCR bridge controls motor rotation frequency. The comparator is coupled to the SCR bridge. An AND gate coupled to the source of periodic signals provides a counting gate during which periodic signals from any suitable source are to be counted and a counter coupled to the AND gate counts the periodic signals. A display displays the number of such periodic signals counted during the counting gate.
    Type: Grant
    Filed: January 28, 1988
    Date of Patent: October 10, 1989
    Assignee: Dart Controls, Inc.
    Inventors: Paul E. Penn, Roger A. Werckman, Jr., John W. Waymire
  • Patent number: 4862048
    Abstract: In a speed control system for a carriage movable along a predetermined path, light beams originating at the ends of the path are deflected by light conductors aboard the carriage so that they are interrupted, as the carriage moves, by a slotted plate extending along the path. The light beams are then deflected by light conductors so that they are directed along the carriage path to light receivers situated at the ends of the path. Electrical pulses from the light receivers are ORed together and converted by a transducer to a signal representative of the actual carriage speed, and by a counter to a signal representative of the carriage position. The carriage position signal is converted, in accordance with a predetermined functional relationship, to a speed set signal which is compared with the actual carriage speed. A signal, representative of the difference between the actual speed and the set speed is used to control the driving motor for the carriage.
    Type: Grant
    Filed: February 10, 1989
    Date of Patent: August 29, 1989
    Assignee: Tsubakimoto Chain Co.
    Inventors: Yoshikazu Shimodaira, Teruo Nozawa
  • Patent number: 4845608
    Abstract: A speed regulator digital speed controller for rotating machinery is comprised of a single-chip microcontroller operating in conjunction with a multiple counter/time peripheral, and is programmed in a high level language. Pulses are generated by a digital speed sensor at a rate too low to give the required speed resolution; these pulses are counted and a preset number toggles a binary gate signal. Two clock counters both having an input connected to a high reference frequency oscillator are gated alternately and accumulate a count depending on the length of the gated on interval. These speed related counts are read during alternating gated off intervals into the microcontroller where the speed error is calculated in real time to a high degree of accuracy and resolution. The speed of an electric motor and a steam turbine, for instance, are regulated.
    Type: Grant
    Filed: December 21, 1987
    Date of Patent: July 4, 1989
    Assignee: General Electric Company
    Inventor: Michael Gdula
  • Patent number: 4833375
    Abstract: A digital motor control system includes a flip-flop latch for receiving motor circuit drive data from a microprocessor, a counter for counting to a predetermined value representing the total duration of a motor drive pulse, a comparator for comparing the incrementing counter value with the motor circuit drive data stored in the latch to provide a pulse width modulated signal, delay circuitry for preventing overlapping of motor brake and motor drive signals, a drive gate controlled in part by said pulse width modulated signal for applying a drive signal for motor control, and a brake gate for applying a brake signal for motor control.
    Type: Grant
    Filed: March 25, 1988
    Date of Patent: May 23, 1989
    Assignee: NCR Corporation
    Inventor: James R. Del Signore, II
  • Patent number: 4827201
    Abstract: A digital servo system comprising source means of a clock signal, counter means, latch means which latches a predetermined lower bits of the output of the counter means, means for obtaining a servo control output in response to the latch means, and sequencer means which is applied with a digital data of which the pulse interval or the phase is processed, and controls passing or nonpassing of the clock signal to the counter means in response to the digital data and obtains a latch pulse for the latch device.
    Type: Grant
    Filed: September 30, 1987
    Date of Patent: May 2, 1989
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kenji Ito
  • Patent number: RE33500
    Abstract: A digital proportional-integral controller for controlling the speed of a d.c. electric motor in a copying machine and synchronizing it with the speed of another motor in the copying machine. The proportional stage and the integral stage of the controller are each formed by an up/down counter which counts up or down depending upon the pulses of the actual speed signal and the reference signal. Logic circuits are provided for processing the speed signal pulses and the reference signal pulses before they are fed to the up/down counters. The controller also has an interface for a two-wire bus system over which data and commands for adjusting and varying the control parameters can be input.
    Type: Grant
    Filed: July 1, 1988
    Date of Patent: December 18, 1990
    Assignee: Oce-Nederland B.V.
    Inventor: Wilhelmus T. L. Bisseling