Acceleration Control Patents (Class 318/276)
  • Patent number: 11444557
    Abstract: A gate drive semiconductor device includes: external terminals to which PWM control signals are supplied; external terminals outputting a drive signal for driving a three-phase BLDC motor; external terminals to which the counter electromotive voltage generated by driving the three-phase BLDC motor is supplied; a zero-cross determination unit generating an interrupt signal indicating timing at which the counter electromotive voltage intersects with a midpoint potential of the three-phase BLDC motor based on the PWM control signal and the counter electromotive voltage; and an external terminal outputting the interrupt signal.
    Type: Grant
    Filed: January 13, 2021
    Date of Patent: September 13, 2022
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Seigi Ishiji, Minoru Kurosawa
  • Patent number: 11410629
    Abstract: An output voltage regulating circuit includes a PWM IC, a voltage regulating speed control unit, a first n-type switch unit, a first capacitor, a resistor unit, and a voltage output unit, wherein the voltage regulating speed control unit includes a second switch unit, a second capacitor, a current source, and a comparator; when the PWM IC receives a signal to increase or decrease the output voltage, the PWM IC correspondingly controls the voltage output unit to increase or decrease the output voltage, and simultaneously controls the second switch unit to turn on and then cut off such that the voltage at the first terminal of the second capacitor is gradually increased, and before increasing to the reference voltage, the comparator outputs a high voltage level to turn on the first n-type switch unit such that the compensation terminal of the PWM IC is directly connected to the first capacitor.
    Type: Grant
    Filed: December 4, 2017
    Date of Patent: August 9, 2022
    Assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd.
    Inventor: Xianming Zhang
  • Patent number: 11177751
    Abstract: A motor controller, an active short circuit thereof, and a method for controlling active short via the same. An enabling signal is generated and outputted in response to determining that a vehicle is to enter a safe mode and a speed of a motor exceeds a threshold. Currents of a direct-axis and a quadrature-axis of the motor are adjusted to characteristic currents according to the enabling signal. An action flag signal and a control signal that corresponds to the enabling signal are generated and outputted in response to determining that the currents of the direct-axis and the quadrature-axis are adjusted to be the characteristic currents. A driving signal corresponding to the control signal is generated and outputted according to the action flag signal. A driving circuit safely controls a corresponding switch transistor in the inverter to be turned on based on the driving signal.
    Type: Grant
    Filed: February 19, 2020
    Date of Patent: November 16, 2021
    Assignee: SUNGROW POWER SUPPLY CO., LTD.
    Inventors: Yang Min, Wenjie Chen
  • Patent number: 10234872
    Abstract: A method for launching an unmanned aerial vehicle (UAV) comprises: receiving a pre-launching signal; detecting, via at least one sensor of the UAV, at least one status parameter of the UAV in response to receiving the pre-launching signal; determining a launching mode of the UAV according to the at least one detected status parameter of the UAV; and launching the UAV according to the determined launching mode of the UAV.
    Type: Grant
    Filed: December 27, 2016
    Date of Patent: March 19, 2019
    Assignee: ZEROTECH (CHONGQING) INTELLIGENCE TECHNC
    Inventors: Shuaiqin Wang, Xiongwei Zhu, Yiqiang Zheng
  • Patent number: 9670711
    Abstract: A movable partition system includes a movable partition including coupled panels and a lead post engaged with and movable along a track. A motor control system includes a motor coupled to the movable partition and a switching circuit coupled to the motor and for selectively coupling the motor to a positive power source and a negative power source responsive to one or more PWM signals. An encoder is configured for generating one or more rotation signals indicative of operational direction and operational speed of the motor. A motor controller is coupled to the switching circuit and is configured for improving airflow around the panels of the movable partition when the lead post of the movable partition is between a predefined position and a fully retracted position indicative of a billowing effect for the panels by adjusting pulse widths of the PWM signals to control rotational speed of the motor.
    Type: Grant
    Filed: October 2, 2015
    Date of Patent: June 6, 2017
    Assignee: Won-Door Corporation
    Inventors: Duane O. Hall, E. Carl Goodman, W. Michael Coleman, John G. Garrett, III
  • Patent number: 8847523
    Abstract: An electronic drive includes an electro-mechanical brake associated with a direct-current motor. A first valve or diode connects one of the terminals of the direct-current motor with the first electrical terminal of the brake in a forward direction. A second valve or diode connects the other terminal of the direct-current motor with the first electrical terminal of the brake. A second electrical terminal of the brake is at least indirectly connected with a reference voltage.
    Type: Grant
    Filed: November 28, 2011
    Date of Patent: September 30, 2014
    Assignee: Aktiebolaget SLF
    Inventors: Remy Bringold, Klaus Pfeffer
  • Patent number: 8482876
    Abstract: A method and system for sensing the current applied to the motor of a data storage device and determining whether a shock event has occurred by processing the sensed current levels.
    Type: Grant
    Filed: January 25, 2012
    Date of Patent: July 9, 2013
    Assignee: Apple Inc.
    Inventor: Thomas R. Colligan
  • Patent number: 8476852
    Abstract: A controller for a brushless motor that includes a processor, a first timer, a second timer, a compare register, a comparator, an input, and one or more outputs. The processor starts the first timer in response to a signal at the input. The first timer then generates an interrupt after a first period. In response to the interrupt, the processor generates a first control signal at the outputs. The processor also loads the compare register and starts the second timer in response to either the input signal or the interrupt. The comparator then generates a second control signal at the outputs when the second timer and the compare register correspond. Additionally, a motor system that includes the controller.
    Type: Grant
    Filed: April 13, 2011
    Date of Patent: July 2, 2013
    Assignee: Dyson Technology Limited
    Inventors: David John Hawker, Hanping Dai
  • Patent number: 8258726
    Abstract: A system for cooling a battery mounted on a vehicle using air within a vehicle, independently of the travelling state of the vehicle. The air within a vehicle compartment is guided to a battery mounted on a vehicle to cool the battery. A controller determines a basic fan speed v of the cooling fan based on a battery temperature and an ambient temperature. Further, the controller calculates an increment ?v of the fan speed in accordance with the vehicle speed and the degree of window opening and determines a final fan speed V according to V=v+?v, to drive the cooling fan. By controlling the fan speed to increase, it is possible to cool the battery even when the base pressure of the inlet-side static pressure of the cooling fan becomes negative pressure compared to when the windows are closed.
    Type: Grant
    Filed: February 4, 2010
    Date of Patent: September 4, 2012
    Assignee: Panasonic EV Energy Co., Ltd.
    Inventors: Jun Okuda, Toshiaki Nakanishi, Norihito Yuno
  • Patent number: 8217601
    Abstract: A robust method for detecting a relative position of a feedback device, such as an encoder or resolver, coupled to a shaft, such as a motor shaft, is provided. To detect the relative position, electrical commands are issued in an open loop mode to spin the motor shaft an amount greater than the apparent rotational angle between two consecutive markers of the position feedback device, such that the net mechanical rotation is equal to or greater than the total rotational angle between two consecutive markers.
    Type: Grant
    Filed: February 2, 2010
    Date of Patent: July 10, 2012
    Assignee: Parker-Hannifin Corporation
    Inventor: Yun-Chich “Jack” Lin
  • Patent number: 8107183
    Abstract: A method and system for sensing the current applied to the motor of a data storage device and determining whether a shock event has occurred by processing the sensed current levels.
    Type: Grant
    Filed: July 2, 2008
    Date of Patent: January 31, 2012
    Assignee: Apple Inc.
    Inventor: Thomas R. Colligan
  • Patent number: 8044616
    Abstract: A system for controlling a disk in a disk drive includes a motor control circuit and a first circuit that retrieves firmware speed control instructions from non-volatile memory. During retrieval of the firmware speed control instructions, at least one of the motor control circuit determines a position of the disk, one of the first circuit and the motor control circuit spins up the disk and the motor control circuit ramps up a speed of the disk. The first circuit performs speed control of the disk based on the firmware speed control instructions.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: October 25, 2011
    Assignee: Marvell International Ltd.
    Inventors: Ravishanker Krishnamoorthy, Foo Leng Leong
  • Patent number: 7619379
    Abstract: A motor control device includes a recording module and a controlling module. The recording module has a revolution speed table recording a plurality of predetermined revolution speed values. The controlling module receives a reference revolution speed control signal and measures the reference revolution speed control signal to correspondingly generate a reference measuring value. The recording module records the reference measuring value corresponding to one of the predetermined revolution speed values in the revolution speed table.
    Type: Grant
    Filed: March 15, 2007
    Date of Patent: November 17, 2009
    Assignee: Delta Electronics, Inc.
    Inventors: Hong-Jen Chen, Keittipermsak Rungcharoen, Sukudom Saravut
  • Patent number: 7602131
    Abstract: A system includes a current control module that supplies current to a voice coil motor during a first period to rotate an actuator arm in a first rotational direction, that discharges the current from the voice coil motor after the first period, and that generates a control signal a predetermined period after the current is discharged. A back electromagnetic force (bemf) module generates a bemf signal in response to the control signal. A speed control module determines a speed of the actuator arm based on the bemf signal.
    Type: Grant
    Filed: December 4, 2008
    Date of Patent: October 13, 2009
    Assignee: Marvell International Ltd.
    Inventor: Siew Yong Chui
  • Patent number: 7579796
    Abstract: Control of rotational speed of a direct current multi-phase brushless motor is provided using an apparatus and method that works at low speed but does not depend upon Hall effect sensors. An apparatus for accelerating rotation of the motor shaft has a power stage circuit coupled to a back Electromotive Force (EMF) sensor circuit and a microprocessor. The power stage pulses at a duty cycle less than 100% under control of the microprocessor. The back EMF sensor circuit measures an order with respect to voltage of at least one phase relative to one or more other phases during off-time. The microprocessor determines one or more phases to be pulsed, and the polarity of the pulses based on the measured order. A method for sustaining rotation pulses the phases, measures order with respect to voltage of at least one phase relative to one or more other phases, and updates commutation state based on the measured order.
    Type: Grant
    Filed: June 24, 2008
    Date of Patent: August 25, 2009
    Assignee: Castle Creations, Inc.
    Inventor: Richard A. Hofer
  • Patent number: 7545111
    Abstract: A method for testing electric motor shut-off including injecting current into an electric motor, applying at least one of a short or an open to the electric motor for a predetermined length of time, calculating the rate of decay of the current and comparing rate of the decay with a predetermined decay criteria. In one implementation, a predefined sequence of opening and short circuiting the electric motor is used, and the shut-off path tests for the motor three phases can be verified with one test.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: June 9, 2009
    Assignees: Chrysler LLC, GM Global Technology Operations, Daimler AG, Bayerische Motoren Werke Aktiengesellschaft
    Inventors: Zhenxing Fu, Marcus Heller
  • Patent number: 7468590
    Abstract: A motor controller comprises an angular position module that determines an angular position of a disk. A spin-up module performs a spin-up of the disk. A ramp-up module ramps up a speed of the disk after the spin-up. A speed control module controls the speed of the disk based on a control program that is downloaded to the motor controller during a boot-up operation of a disk drive. The angular position module determines the angular position of the disk before handover of control to the control program.
    Type: Grant
    Filed: February 12, 2008
    Date of Patent: December 23, 2008
    Assignee: Marvell International Ltd.
    Inventors: Ravishanker Krishnamoorthy, Foo Leng Leong
  • Patent number: 7466095
    Abstract: A system and method for controlling an actuator includes a control module that communicates with a plurality of switching devices to generate current through a voice coil motor during a first time period so that an actuator arm rotates in a first rotational direction in response to the current. The control module controls the switching devices to discharge the current from the voice coil motor during a second time period less than the first time period so that the first rotational direction of the actuator arm is maintained after discharging the current. The control module further includes a back electromagnetic force (bemf) module for determining a bemf voltage after controlling the switching devices to discharge the current, and an actuator arm speed control module for determining an actuator arm speed in response to the bemf voltage.
    Type: Grant
    Filed: June 19, 2006
    Date of Patent: December 16, 2008
    Assignee: Marvell International Ltd.
    Inventor: Siew Yong Chui
  • Patent number: 7400103
    Abstract: Control of rotational speed of a direct current multi-phase brushless motor is provided using an apparatus and method that works at low speed but does not depend upon Hall effect sensors. An apparatus for accelerating rotation of the motor shaft has a power stage circuit coupled to a back Electromotive Force (EMF) sensor circuit and a microprocessor. The power stage pulses at a duty cycle less than 100% under control of the microprocessor. The back EMF sensor circuit measures an order with respect to voltage of at least one phase relative to one or more other phases during off-time. The microprocessor determines one or more phases to be pulsed, and the polarity of the pulses based on the measured order. A method for sustaining rotation pulses the phases, measures order with respect to voltage of at least one phase relative to one or more other phases, and updates commutation state based on the measured order.
    Type: Grant
    Filed: August 8, 2006
    Date of Patent: July 15, 2008
    Assignee: Castle Creations, Inc.
    Inventor: Richard A. Hofer
  • Patent number: 7385364
    Abstract: A system and method for determining the rotational speed of a motor, such as a three-phase disk drive motor, detects back electromotive force voltage generated during operation of the motor with an automatic pole calibration to minimize or eliminating variations in the wave of a freeze signal. A phase voltage at a winding is compared against a center tap (CT) voltage. Once the phase voltage falls to a specified voltage level, a detect signal is generated. A predetermined time after the detect signal is generated, a freeze signal is generated for freezing at least the circuit associated with the winding.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: June 10, 2008
    Assignee: Marvel International Ltd.
    Inventors: Kuong Hoo, legal representative, Foo Leng Leong, Siew Yong Chui, Cheng Yong Teoh, Sakti Pada Rana
  • Patent number: 7382104
    Abstract: The present invention relates to portable powered devices or tools for residential, commercial, or industrial applications, in which the power source may be carried on the back of the individual user, power is transferred via a flexible drive shaft, and the powered devices or tools may be quickly connected to or disconnected from the power source via a quick-connect power take-off and power take-on to allow the user to quickly, safely and ergonomically accomplish a variety of tasks, each requiring a different device or tool. Among residential, commercial, or industrial applications, the invention relates to power sources which are light-weight internal combustion engines or AC or DC powered electric motors and to portable powered tools for landscaping, maintenance and repair; such as, without limitation, string-trimmers, edge-trimmers, hedge cutters, brush saws, blowers, drills, buffers, grinders, sanders, drainer cleaners, or sump pumps.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: June 3, 2008
    Inventors: Bradley A. Jacobson, David E. Milton
  • Patent number: 7348741
    Abstract: A vehicle which uses an internal combustion engine and a motor generator as drive sources is provided with a battery disposed under a seat and a fan for cooling the battery. Power is exchanged between the motor generator and battery via an inverter. An electronic control unit estimates the level of background noise which is noise other than the operating sound of the fan in the passenger compartment based on the vehicle speed and rotation speed, etc., of the internal combustion engine. Then, the electronic control unit calculates an operation command value for the fan based on the estimated background noise level and temperature level of the battery and controls the rotation speed of the fan through the operation command value. As a result, it is possible to effectively cool the battery while reducing sensible noise caused by the operating sound of the fan.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: March 25, 2008
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hideto Minekawa, Teruo Ishishita, Yoshiaki Kikuchi
  • Patent number: 7332883
    Abstract: Disk drives such as hard (magnetic) disk drives take a certain amount of time to initialize and “spin up” to the operational rotational speed of the disk or disks, thereby creating a time lapse from power up to when data can first be read from or written to the disk drive. This time lapse can be reduced, whereby some tasks conventionally done sequentially instead are performed in parallel. For example, the motor controller that controls the spindle motor can perform its portion of the initialization beginning at the same time that the remaining electronic components, including the hard disk controller, begin their initialization process including downloading firmware. Additionally, other portions of the initialization process typically performed by firmware can be performed by dedicated circuitry or a bootstrap program in the motor controller and hard disk controller, thereby not requiring the relatively slow downloading of system firmware.
    Type: Grant
    Filed: February 9, 2006
    Date of Patent: February 19, 2008
    Assignee: Marvell International Ltd.
    Inventors: Ravishanker Krishnamoorthy, Foo Leng Leong
  • Patent number: 7141946
    Abstract: A method and apparatus for use with a motor controller that receives a command velocity and that applies voltages to drive a motor at the command velocity, the apparatus comprising a dual inertia lost motion assembly including a motor and a load couplable to the motor, the lost motion assembly characterized by at least some lost motion between the motor and the load, the motor and load together characterized by a total assembly inertia, an acceleration error determiner for generating an acceleration error that is the difference between a derivative of the command velocity and a motor acceleration value and a low pass acceleration error filter filtering the acceleration error and having a gain set as a percentage of the total assembly inertia, the acceleration error filter providing the filtered signal to the controller, the controller using the filtered signal to adjust the applied voltages.
    Type: Grant
    Filed: September 15, 2003
    Date of Patent: November 28, 2006
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Thomas J. Rehm, Peter B. Schmidt, John Joseph Golownia
  • Patent number: 7026775
    Abstract: Method and apparatus for controlling a moving speed of a moving body, wherein at least one transient target speed value in addition to a final target speed value is used to control the moving speed in an accelerating period between a moment of initiation of a movement of the moving body and a moment at which the moving speed should coincide with the final target speed value. The transient target speed is updated at a predetermined timing, or changed to the final target speed value, or from one transient value to another transient value before it is changed to the final target speed value, so that the moving speed is smoothly increased to the final target speed value, without an overshoot beyond the final target speed value.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: April 11, 2006
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Masatoshi Kokubo, Shigeki Akiyama
  • Patent number: 7023155
    Abstract: Method and apparatus for accelerating a multi-phase motor having a rotatable rotor is disclosed. A first commutation state in which the rotor resides is identified, a first position of the rotor within the first commutation state is determined (preferably within one to two electrical degrees), and a travel distance for the rotor to advance from the first position to a second position is determined. An optimized activation time is next determined for utilizing substantially all available motor torque, and a first drive pulse is applied for the activation time to advance the rotor to the second position. The process is repeated until an intermediate velocity is reached, after which back electromotive force (bemf) commutation is used for control of the motor. The apparatus includes a controller programmed with routines that utilize speeds and accelerations of the motor in accordance with basic Newtonian laws to determine optimized activation times.
    Type: Grant
    Filed: June 5, 2003
    Date of Patent: April 4, 2006
    Assignee: Seagate Technology LLC
    Inventor: Triet Minh Tieu
  • Patent number: 7012391
    Abstract: Method and apparatus for accelerating a motor to an operational velocity using a continuous sequence of current limit values derived from a plurality of discrete current limit values. Each discrete current limit value establishes a maximum current magnitude for the motor over a plurality of intermediate velocities less than the operational velocity. Each current limit value in the continuous sequence of current limit values has a different magnitude for each different one of the plurality of intermediate velocities. The continuous sequence of current limit values are preferably derived by generating coefficients of a multi-order polynomial curve in relation to the discrete current limit values, and obtaining the continuous sequence of current limit values in relation to said coefficients. Faster acceleration, reduced current spiking and less acoustic noise during motor acceleration are thereby obtained.
    Type: Grant
    Filed: April 9, 2003
    Date of Patent: March 14, 2006
    Assignee: Seagate Technology LLC
    Inventor: James Wilford DuLaney
  • Publication number: 20040251861
    Abstract: Method and apparatus for accelerating a multi-phase motor having a rotatable rotor is disclosed. A first commutation state in which the rotor resides is identified, a first position of the rotor within the first commutation state is determined (preferably within one to two electrical degrees), and a travel distance for the rotor to advance from the first position to a second position is determined. An optimized activation time is next determined for utilizing substantially all available motor torque, and a first drive pulse is applied for the activation time to advance the rotor to the second position. The process is repeated until an intermediate velocity is reached, after which back electromotive force (bemf) commutation is used for control of the motor. The apparatus includes a controller programmed with routines that utilize speeds and accelerations of the motor in accordance with basic Newtonian laws to determine optimized activation times.
    Type: Application
    Filed: June 5, 2003
    Publication date: December 16, 2004
    Inventor: Triet Minh Tieu
  • Publication number: 20040239276
    Abstract: A control method for controlling a speed of a movable machine element of a numerically controlled industrial processing machine with jerk limitation is described. The processing machine can be, for example, a machine tool, a production machine and/or a robot. A travel path of the movable machine element is first decomposed into a plurality of sequentially arranged, interpolatable travel sections. Jerk profiles are then determined for the interpolatable travel sections, which are modified with a parameter-dependent shape function. The modified jerk profiles provide a filter action that can be represented by bandpass filters having blocking frequencies. The blocking frequencies of the bandpass filters are selected so as to substantially correspond to characteristic frequencies of the machine element. The control method significantly improves the machine dynamics without sacrificing accuracy.
    Type: Application
    Filed: April 2, 2004
    Publication date: December 2, 2004
    Applicant: SIEMENS AKTIENGESELLSCHAFT
    Inventors: Uwe Ladra, Elmar Schafers
  • Publication number: 20040066158
    Abstract: A method and apparatus for improving the timing of a seek operation through the removal of the coast phase of conventional model reference waveform type control systems are provided. With the apparatus and method, the coast phase is removed such that an acceleration phase is immediately followed by a deceleration phase in the waveform of the control system. A (1-Cos)/2 shaping is applied to the resulting square waveform so that the affects of high frequency harmonics are minimized. The resulting “cosine bang-bang” waveform provides a reduction in seek time when compared to conventional model reference waveform based control. In addition to the above, the present invention provides a controller architecture in which the cosine bang-bang waveform may be applied to a voice coil motor to control the actuation of the read/write heads of a disc drive.
    Type: Application
    Filed: October 3, 2003
    Publication date: April 8, 2004
    Inventor: Apurva Dolatrai Naik
  • Patent number: 6563287
    Abstract: A motor starter. The motor starter comprises a motor; start, run, shorting and transition contactors operably associated with the motor; and run, start, shorting and transition auxiliary contactors. The transition auxiliary contactor operably controls the operation of a shorting contactor, and the shorting auxiliary operatively controls the operation of the run contactor.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: May 13, 2003
    Assignee: American Standard International Inc.
    Inventors: Matthew A. Shepeck, Michael W. Murry
  • Patent number: 6552507
    Abstract: Acceleration/deceleration control is performed on the basis of a designated jerk control such that a maximum absolute value Jmax of jerk value, which is differential value of acceleration, is made not larger than a predetermined value when a commanded quantity of servomotor movement is smaller than a minimum quantity Smin of motor movement which is required to allow the movement of the servomotor to reach a predetermined maximum velocity Vmax and a predetermined maximum acceleration Amax.
    Type: Grant
    Filed: April 13, 2001
    Date of Patent: April 22, 2003
    Assignee: Seiko Epson Corporation
    Inventor: Hiroshi Miyazawa
  • Patent number: 6528962
    Abstract: A control unit suppresses fluctuation in speed of a motor in a printer. The control unit has a speed detecting part for detecting the speed of the motor in a predetermined period tv, and an average speed calculating part for calculating an average speed based on a current speed detected by the speed detecting part, and on a speed which has been detected n (n≧2) periods tv before, ntv corresponding to substantially half period of the fluctuation in speed of the motor. The control unit also has a speed control part for controlling the speed of the motor based on a deviation of the average speed from a target speed of the motor.
    Type: Grant
    Filed: July 26, 2000
    Date of Patent: March 4, 2003
    Assignee: Seiko Epson Corporation
    Inventors: Hitoshi Igarashi, Masanori Yoshida
  • Patent number: 6501244
    Abstract: A method and apparatus for controlling a permanent magnet synchronous motor (8) coupled to a turbo engine such that transient current and steady state current are minimized. The method comprises the steps of, for a given DC bus voltage, determining an acceleration profile as a function of a voltage-offset value, a low-speed rated speed value, a high-speed rated speed value, a first desired speed for warming up the turbo engine, and a second desired speed where the turbo engine has sufficient torque to accelerate to its rated speed without the aid of the permanent magnet synchronous motor (8).
    Type: Grant
    Filed: July 6, 2001
    Date of Patent: December 31, 2002
    Assignee: Ballard Power Systems Corporation
    Inventor: Bing Cheng
  • Patent number: 6492789
    Abstract: A method and apparatus for controlling a permanent magnet synchronous motor (8) coupled to a turbo engine such that transient current and steady state current are minimized. The method comprises the steps of, for a given DC bus voltage, determining an acceleration profile as a function of a voltage-offset value, a low-speed rated speed value, a high-speed rated speed value, a first desired speed for warming up the turbo engine, and a second desired speed where the turbo engine has sufficient torque to accelerate to its rated speed without the aid of the permanent magnet synchronous motor (8).
    Type: Grant
    Filed: July 6, 2001
    Date of Patent: December 10, 2002
    Assignee: Ballard Power Systems Corporation
    Inventor: Bing Cheng
  • Patent number: 6040666
    Abstract: A machine tool has a spindle with a tooling body mounted thereon, a detector for detecting an acceleration time for the tooling body to reach from a rotation start to a predetermined rpm, a controller for controlling an rpm of the spindle under a lowered limit when the acceleration time is longer than a reference time. Another detector detects an asymmetricity of radial forces acting on the spindle, and the controller controls the rpm of the spindle under a lowered limit when the asymmetricity of radial forces exceeds a reference degree.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: March 21, 2000
    Assignee: Toshiba Kikai Kabushiki Kaisha
    Inventors: Hirohiko Honda, Yoshinobu Kato
  • Patent number: 5960376
    Abstract: In order to control a movable object such as an automobile, the differential of acceleration is derived and used as control information. In order to derive that differential, a value representing the acceleration may be differentiated, but preferably a sensor is provided which generates a direct measurement of the differential of acceleration. In one example of such a sensor, a pendulum has a coil thereon which interacts with the magnetic field of a magnet on a casing supporting the pendulum. A current is supplied to the coil such as to generate a force resisting movement of the pendulum. It is then found that the voltage across the coil corresponds to the differential of acceleration.
    Type: Grant
    Filed: July 1, 1997
    Date of Patent: September 28, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Makoto Yamakado, Yuzo Kadomukai
  • Patent number: 5877955
    Abstract: A transducerless position determining system and method of using the same for determining the relative position of a mechanical member or component which is driven by an electric motor within an electromechanical system. The transducerless position determining system includes a microcontroller with a software model that simulates the acceleration, deceleration and velocity characteristics of the electric motor as a function of applied voltage thereto and the load characteristics of the electromechanical system. The applied voltage is sampled electronically to monitor its amplitude level, and microcontroller software and associated circuitry is used to accurately detect application and removal of the applied voltage to the electric motor.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: March 2, 1999
    Assignee: Waterstrike Incorporated
    Inventor: David A. Struyk
  • Patent number: 5485065
    Abstract: A position command method and apparatus for shortening the acceleration and deceleration times of a servo controlled apparatus by effectively utilizing the torque of the controlled apparatus. A value of speed per unit time is developed on the basis of speed and position data, and a constant speed or an acceleration or deceleration function processing may be selectably performed. In the position commanding method and its unit of the present invention, the deceleration stop distance of output speed is computed at all times or is held as a list data as described above and moreover is compared with a residual distance XR. Consequently, the deceleration stop distance does not have to coincide with the residual portion from the acceleration command, and the acceleration/deceleration curve alone can be realized in an independent form. Also, the speed change can be made smoother by correcting the cross point of independently formed acceleration and/or deceleration curves defining a corner section.
    Type: Grant
    Filed: April 1, 1994
    Date of Patent: January 16, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akira Kaneko, Norikazu Iguchi, Takahiro Hayashida, Torao Takeshita, Yoshio Shinohara
  • Patent number: 5323097
    Abstract: A procedure for producing a speed reference signal for a crane motor control when the converter feeding the motor is controlled by means of at least one manually operated controller. To allow the speed reference signal to be changed, the controller has a control position in which the value of the speed reference signal is changed as a function of time. In order to facilitate more accurate manual control of the motor speed, when the speed of the motor is above a predetermined minimum value, the time derivative of the speed reference signal is changed during acceleration of the motor.
    Type: Grant
    Filed: June 16, 1993
    Date of Patent: June 21, 1994
    Assignee: Kone Oy
    Inventor: Tapani Kiiski
  • Patent number: 5207520
    Abstract: A device for PWM control of the printer carriage motor (1) which has a circuit (65) for generating a first PWM pulses of 100% duty ratio, a circuit for computing second PWM pulses (31, 37, 39, 15, 17, 53, 57, 59) according to the PI control method based on the difference between the motor current speed and the predetermined standard speed, and a circuit (121) for holding the optimum integrated value for controlling the motor current speed agree with the standard speed. Until the motor current speed reaches a predetermined transfer speed slightly lower than the standard speed, the carriage motor is accelerated with the maximum acceleration according to the first PWM pulses, when the transfer speed is reached, the optimum integrated value is set as the initial integrated value of the PI control, and thereafter the speed control is carried out according to the PI control method.
    Type: Grant
    Filed: July 19, 1991
    Date of Patent: May 4, 1993
    Assignee: Seiko Epson Corp.
    Inventor: Hirotomo Tanaka
  • Patent number: 4808895
    Abstract: This invention provides an acceleration control apparatus suitable for use as various kinds of feed control. A comparator circuit compares a command value supplied from an acceleration commanding unit and an actual value of acceleration detected by a signal generator connected to a motor to be controlled. A voltage command computing circuit provided at a rear stage of the comparator circuit effect predetermined processing of an acceleration deviation signal on the basis of the result of this comparison to output the resultant command voltage to a driving control circuit. This command voltage is output to the motor and thus acceleration of the motor is controlled.
    Type: Grant
    Filed: November 30, 1987
    Date of Patent: February 28, 1989
    Assignee: Toshiba Machine Co., Ltd.
    Inventors: Jun Fujita, Yoshinori Nakanishi, Etsuzi Oda, Kazutaka Yamashita