Automatic And/or With Time-delay Means Patents (Class 318/364)
  • Patent number: 10498282
    Abstract: A common mode noise reduction section performs a first noise reduction process in a first system, a second noise reduction process in a second system and a third noise reduction process in the case where the two systems have a phase, a current for which that flows through a stray capacitance is not canceled out in at least one PWM cycle in a current control cycle after the first noise reduction process is performed and the second noise reduction process is performed. The third noise reduction process includes shifting a PWM count for each phase in the first system by a first predetermined amount and shifting a PWM count for each phase in the second system by a second predetermined amount such that the currents for such a phase which flow through the stray capacitances in the two systems cancel out each other in the relevant PWM cycle.
    Type: Grant
    Filed: November 9, 2018
    Date of Patent: December 3, 2019
    Assignee: JTEKT CORPORATION
    Inventor: Hiroshi Sumasu
  • Patent number: 9436916
    Abstract: A method for determining a correction characteristic curve for adapting a characteristic curve of an injection system, in which the correction characteristic curve includes at least one deviation of a measured characteristic curve from a setpoint characteristic curve, the at least one deviation including a sum tolerance of at least two components of the injection system, which have an effect on the characteristic curve.
    Type: Grant
    Filed: June 27, 2011
    Date of Patent: September 6, 2016
    Assignee: Robert Bosch GmbH
    Inventor: Guenter Veit
  • Patent number: 8901864
    Abstract: Proposed is a driver having dead-time compensation function. The driver having dead-time compensation function generates an output voltage according to a voltage command and a frequency command. The driver includes an inverter, an output current detector and a control unit. The inverter receives a DC voltage and operates with a pulse width modulation mode so that the driver outputs the output voltage and an output current. The output current detector detects the current value of the output current to generate a output current detecting signal. The control unit outputs a switching control signal to inverter according to the voltage command and the frequency command. The control unit corrects a reference command according to dead-time and the output current detecting signal related to the output current so that amplitude and waveform smoothness of the output voltage and the output current are compensated.
    Type: Grant
    Filed: August 20, 2012
    Date of Patent: December 2, 2014
    Assignee: Delta Electronics, Inc.
    Inventors: Chien-Yu Chi, Chien-Ping Huang
  • Patent number: 8847524
    Abstract: Braking current generated by an electrical motor on mining equipment during a retard interval is switched through one or more grid resistors that are liquid cooled. Under low ambient temperatures, a heating current can be switched through the grid resistors when the electrical motor is not operating in a retard interval. An integrated cooling system can be used to cool grid resistors and power modules. Heat dissipated by the grid resistors and the power modules can be circulated through auxiliary heating loops to heat portions of the mining equipment under low ambient temperatures. Multiple liquid-cooled power modules, liquid-cooled grid resistors, auxiliary heating loops, control modules, radiators, and pumps can be coupled by a liquid distribution system with various combinations of parallel and serial branches. Temperature, pressure, and flow rate in each branch can be independently controlled. Operation of the integrated cooling system can be controlled by a computational system.
    Type: Grant
    Filed: September 29, 2011
    Date of Patent: September 30, 2014
    Assignee: Siemens Industry, Inc.
    Inventor: Joy Mazumdar
  • Patent number: 8823297
    Abstract: The invention relates to a method of control implemented in a variable speed drive for controlling the deceleration of an electric motor (M) in the case of electrical power outage. The method of control comprises: a step of determining the Joule-effect losses to be applied to the electric motor (M) and to the variable speed drive according to a deceleration ramp to be applied to the electric motor (M) during an electrical power outage, a step of determining the flux reference (?ref) as a function of the said Joule-effect losses to be applied to the electric motor (M) and to the variable speed drive.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: September 2, 2014
    Assignee: Schneider Toshiba Inverter Europe SAS
    Inventors: Ludovic Kermarrec, Francois Malrait
  • Patent number: 8742703
    Abstract: The invention relates to a blower apparatus (1) having a blower wheel (4) for generating a blower air flow (50). The blower wheel (4) is arranged in a housing (2), wherein the blower wheel is driven by an electric drive motor (8). A blower tube (6) via which the generated blower air flow (50) is guided connects at an outlet (5). A control unit (17) is provided for controlling the rotational speed of the electric drive motor. For a quick reduction of the blower air flow (50), it is provided that the control unit (17) supports the deceleration of the drive motor (8) through a braking current (I).
    Type: Grant
    Filed: December 15, 2011
    Date of Patent: June 3, 2014
    Assignee: Andreas Stihl AG & Co. KG
    Inventors: Andreas Binder, Arne Untermann, René Wichert
  • Patent number: 8729836
    Abstract: A control device for a hoist, which enables easy judgment of the lifetime of a brake of a hoist is provided. The time setting unit sets the time from startup of a double winding induction motor to disengagement of the brake and the time from start of engagement of the brake to stopping of the double winding induction motor in accordance with the time from the startup of the double winding induction motor to generation of torque. The time changing unit detects if power-supply frequency of a power supply is 50 Hz or 60 Hz and can change at least one of the time from the startup of the double winding induction motor to the disengagement of the brake and the time from stopping of driving of the brake to stopping of double winding induction motor in accordance with the power-supply frequency of the power supply.
    Type: Grant
    Filed: September 29, 2010
    Date of Patent: May 20, 2014
    Assignee: Kito Corporation
    Inventors: Masaharu Maruno, Daisuke Matsuo, Kazuho Furukawa
  • Patent number: 8670844
    Abstract: The invention relates to a device, particularly a machine tool device, having at least one computer (10), at least one transmitter (12) for transmitting a transmission signal (S1, S2), at least one receiver (14) for receiving at least one receiving signal (E1, E2, E3, E4) excited by the transmission signal (S1, S2), and at least one analysis unit (16) which is provided to calculate at least one parameter (P1, P2, P3, P4) by means of the receiving signal (E1, E2, E3, E4). The invention provides that the computer unit (10) is provided to compare the parameter (P1, P2, P3, P4) to at least one comparison parameter (V1, V2, V3, V4) calculated by means of at least one model (M).
    Type: Grant
    Filed: November 11, 2008
    Date of Patent: March 11, 2014
    Assignee: Robert Bosch GmbH
    Inventors: Reiner Krapf, Heiko Braun, Michael Mahler, Alexander Werner Hees
  • Patent number: 8587231
    Abstract: A power tool includes a housing, a brushless DC motor housed inside the housing, a power supply, a control unit, and an input unit such as a trigger switch actuated by a user. The control unit controls the commutation of the motor through a series of power switches coupled to the power supply. The control unit initiates electronic braking of the motor after occurrence of a condition in the input unit, such as trigger release or reduced speed, indicative of the power tool shut-down. A mechanism is provided to power the control unit for a predetermined amount of time after the detection of the condition from the input unit in order to complete the electronic braking of the motor.
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: November 19, 2013
    Assignee: Black & Decker Inc.
    Inventor: Pradeep M. Pant
  • Patent number: 8587230
    Abstract: A power tool includes a brushless DC motor housed inside a tool housing, an input unit, and a control unit. The motor includes a rotor, a stator, and at least one sensor positioned to sense a state of the rotational position of the rotor inside the stator. A control unit controls commutation of the motor through a series of power switches coupled to the power supply. The control unit receives a current sensor state from the sensor and a user-selected speed from the input unit and determines whether the motor has reversed direction using the user-selected speed and the current sensor state. The control unit disables commutation of the motor if the motor has reversed direction until a proper current sensor state is received from the sensor.
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: November 19, 2013
    Assignee: Black & Decker Inc.
    Inventors: Pradeep M. Pant, James Goble
  • Publication number: 20130015790
    Abstract: The invention relates to a method of control implemented in a variable speed drive for controlling the deceleration of an electric motor (M) in the case of electrical power outage. The method of control comprises: a step of determining the Joule-effect losses to be applied to the electric motor (M) and to the variable speed drive according to a deceleration ramp to be applied to the electric motor (M) during an electrical power outage, a step of determining the flux reference (?ref) as a function of the said Joule-effect losses to be applied to the electric motor (M) and to the variable speed drive.
    Type: Application
    Filed: June 21, 2012
    Publication date: January 17, 2013
    Applicant: Schneider Toshiba Inverter Europe SAS
    Inventors: Ludovic KERMARREC, François MALRAIT
  • Patent number: 8299735
    Abstract: A fan system including a motor with a coil, a storage unit, a driver, and a buffer circuit is provided. The coil module has a first connection terminal and a second connection terminal. The storage unit electrically couples with a voltage source, stores electrical energy when the voltage source is available, and releases the stored electrical energy to carry out a brake operation when the voltage source is unavailable. The driver electrically couples with the first and second connection terminals of the coil module to control a direction of an inductor current passing through the coil module. The buffer circuit electrically couples with the coil module. In the brake operation, the buffer circuit operates to form a transient potential between the first and second connection terminals of the coil module and to consume electrical energy of the inductor current, for gradually stopping the motor in a buffering time period.
    Type: Grant
    Filed: January 27, 2010
    Date of Patent: October 30, 2012
    Assignee: Sunonwealth Electric Machine Industry Co., Ltd.
    Inventors: Alex Horng, Tung-An Chen, Cheng-Nan Tsai, Kun-Tien Wu, Kuan-Yin Hou
  • Patent number: 8026680
    Abstract: Methods and apparatus to reduce the stopping time of a spindle motor are disclosed. An example method includes detecting a dissipation current flowing in a spinning motor; determining when the dissipation current drops below a threshold value; and, in response to the dissipation current dropping below the threshold value, applying a voltage to the motor to increase the dissipation current for a duration. In some examples, the voltage is removed from the motor when the motor reaches a predetermined rotational velocity to avoid reverse rotation.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: September 27, 2011
    Assignee: Texas Instruments Incorporated
    Inventor: Triet Tieu
  • Patent number: 8022656
    Abstract: An electric brake circuit for holding an alternating current motor rotor stationary uses a direct current brake acting on an AC motor rotor. The rotor has at least one groove formed therein positioned for alignment with at least one AC motor pole when switching from an alternating current to DC. The AC induction motor holds the rotor stationary against a heavier load by using the grooved rotor with the grooves formed in the rotor aligning with the AC motor's poles.
    Type: Grant
    Filed: August 11, 2008
    Date of Patent: September 20, 2011
    Inventor: Daniel G. Puglisi
  • Patent number: 7911164
    Abstract: A circuit installation that executes full voltage activation, division voltage operation, and delayed breaking brake to electric load by increasing the power to the load activated to promote its activation performance or reducing operation power in the course of operation by the load to save power consumption or limit operation performance of the load.
    Type: Grant
    Filed: October 19, 2010
    Date of Patent: March 22, 2011
    Inventor: Tai-Her Yang
  • Patent number: 7889462
    Abstract: At least one embodiment of the invention relates to a protective circuit for protection of an appliance, in particular of an electric motor, against thermal overloading. In at least one embodiment, the protective circuit includes a first and a second terminal for connecting a temperature detection element; a detection unit for detecting whether a resistance value of the temperature detector element which is connected between the first and the second terminals, is in a first or a second resistance range; a short-circuit detector for identifying whether there is a short circuit between the first and the second terminals; signaling outputs for emitting signal messages to an evaluation unit when the detected resistance value is in the second resistance range and/or when a short circuit has been identified by the short-circuit detector; and a third terminal, which is connected to the second terminal via a predetermined resistance.
    Type: Grant
    Filed: September 6, 2006
    Date of Patent: February 15, 2011
    Assignee: Siemens Aktiengesellschaft
    Inventors: Konrad Spindler, Josef Koller, Markus Meier, Johann Seitz, Andreas Fritsch
  • Publication number: 20100301785
    Abstract: An electromagnetic braking system and method is provided for selectively braking a motor using an electromagnetic brake having an electromagnet, a permanent magnet, a rotor assembly, and a brake pad. The brake assembly applies when the electromagnet is de-energized and releases when the electromagnet is energized. When applied the permanent magnet moves the brake pad into frictional engagement with a housing, and when released the electromagnet cancels the flux of the permanent magnet to allow a leaf spring to move the brake pad away from the housing. A controller has a DC/DC converter for converting a main bus voltage to a lower braking voltage based on certain parameters. The converter utilizes pulse-width modulation (PWM) to regulate the braking voltage. A calibrated gap is defined between the brake pad and permanent magnet when the brake assembly is released, and may be dynamically modified via the controller.
    Type: Application
    Filed: May 29, 2009
    Publication date: December 2, 2010
    Applicants: GM GLOBAL TECHNOLOGY OPERATIONS, INC., The U.S.A. as Represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Donald R. Davis, Nicolaus A. Radford, Frank Noble Permenter, Adam H. Parsons
  • Patent number: 7839105
    Abstract: A circuit installation that executes full voltage activation, division voltage operation, and delayed breaking brake to electric load by increasing the power to the load activated to promote its activation performance or reducing operation power in the course of operation by the load to save power consumption or limit operation performance of the load.
    Type: Grant
    Filed: September 26, 2006
    Date of Patent: November 23, 2010
    Inventor: Tai-Her Yang
  • Patent number: 7834567
    Abstract: A motor drive device for alternately driving a plurality of motors includes a position detection signal processing circuit for processing position detection signals of the plurality of motors, a pre-drive circuit for generating an excitation switching signal of the motors, a plurality of power switching circuits for supplying an electric current to the motors in response to an output from the pre-drive circuit, and a motor switching circuit for instructing a switchover of driving the motors. The position detection signal processing circuit, in response to an input signal to the motor switching circuit, selects a position detection signal of a motor to be driven out of the position detection signals of the plurality of motors, and inputs a position detection processed signal to the pre-drive circuit for selecting one of the plurality of power switching circuits.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: November 16, 2010
    Assignee: Panasonic Corporation
    Inventors: Tomohiko Naya, Tomohiro Inoue
  • Patent number: 7723936
    Abstract: The invention relates to a method for controlled braking of an electrically powered lifting action in the event of a failure, such that at least one of the nominal values for “rotational direction” and/or “operating speed” and/or “door position” and/or “motor capacity” and/or “motor current” is ascertained and compared with an actual value, and such that a motorized braking process or motorized stopping process is triggered by a departure of the actual value from the nominal value that lies outside a predetermined range. In addition the invention relates to a device for applying said method.
    Type: Grant
    Filed: July 27, 2007
    Date of Patent: May 25, 2010
    Assignee: Feig Electronic GmbH
    Inventor: Dirk Schaefer
  • Publication number: 20090160375
    Abstract: Provided is a motor controller for controlling a motor installed at an object such as an electric car operated using a transmitter. A manipulation of a manipulation tool of the transmitter is allocated for brake and reverse modes. A specific value of brake power contained in a signal demodulated by a receiver is stored in a memory unit as a changeover reference value, and a changeover determining unit compares the changeover reference value with the brake power. If the brake power is greater than the changeover reference value, the changeover determining unit transmits a changeover signal to a control unit, and if the manipulation tool is manipulated to a neutral point after the control unit receives the changeover signal, the control unit changes the state of the manipulation tool from brake mode to reverse mode. The changeover reference value can be changed by an operator using an external device.
    Type: Application
    Filed: December 17, 2008
    Publication date: June 25, 2009
    Inventors: Kazuo Katsuyama, Hideo Kitazawa, Takatoshi Morita
  • Patent number: 7268507
    Abstract: A DC power supply, a DC motor driven by DC voltage outputted from the DC power supply, and a control unit outputting a drive control signal to drive the DC motor are provided. A motor drive switch is provided between the DC power supply and the DC motor, and a brake switch is connected to a positive input terminal of the DC motor. The motor drive switch is on while receiving the drive control signal and outputs an output current monitor signal while current is being applied to the motor drive switch. The brake switch is configured to operate faster than the motor drive switch and is off while at least one of the drive control signal and the output current monitor signal is on. Accordingly, when the drive control signal is supplied, the brake switch is turned off, and then the motor drive switch is turned on.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: September 11, 2007
    Assignee: Yazaki Corporation
    Inventor: Yoshihiro Kawamura
  • Patent number: 7157871
    Abstract: Rotation of a capstan motor is detected by a frequency detector, and supplied to a CPU as a rotation detection signal CFG. The CPU derives a period of the rotation detection signal CFG, calculates an average rotational speed of the capstan motor on the basis of the derived period, derives an attenuation value of the rotational speed on the basis of the calculated average speed, and thereby sets a braking time interval. As a result, calculation of the braking time using a highly accurate zero point detection with a frequency detector of one system becomes possible. The apparatus scale can be reduced.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: January 2, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kazuki Azuma
  • Patent number: 7088064
    Abstract: A method for the orientation of a spindle of a numerically controlled and rapidly rotating spindle by which the spindle is brought from an initial rotational speed into a predetermined position of rest. The method includes performing a first phase of orientation of the spindle by braking the spindle to a threshold rotational speed, wherein during the braking a switching over to a position controller is prepared, the switching over is performed at a switching time during a transition from the first phase of orientation to a second phase of orientation, the switching over is continuous in regard to position and/or rotational speed, and wherein a rotational speed of the spindle drops strictly monotonically.
    Type: Grant
    Filed: February 10, 2004
    Date of Patent: August 8, 2006
    Assignee: Dr. Johannes Heidenhain GmbH
    Inventors: Michael Brakelmann, Matthias Fauser
  • Patent number: 7042177
    Abstract: System for braking either linear or rotary electric motor having no permanent magnets comprising at least one servo amplifier and an electronic circuit for generating a pulsed control signal for controlling the braking of the motor. The electronic circuit of the present invention may be responsive to any emergency such as loss of the line power, a motion controller failure, or actuation of a limit switch by a driven member. A method of braking is also disclosed.
    Type: Grant
    Filed: August 5, 2004
    Date of Patent: May 9, 2006
    Assignee: Universal Instruments Corporation
    Inventors: Darrin M. Weiss, Andrew Zalesski
  • Patent number: 6998805
    Abstract: The invention is a motor stop control device for a rotating reel type gaming machine 1 which includes a stepping motor 70 having two pairs of excitation phases as a driving source of reels 3 having a plurality of symbols drawn thereon and in which the stepping motor is stopped in accordance with an operational instruction from outside. The device includes a deceleration transmission mechanism 700 for transmitting the rotation of the stepping motor 70 to rotating shafts for rotating the reels 3 at a predetermined reduction ratio and a main CPU 40 for performing control for reducing the rotating speed of the stepping motor 70 when a stop command for the stepping motor 70 is generated according to an operational instruction from the outside and for performing stop control of the stepping motor 70 through two-phase excitation.
    Type: Grant
    Filed: October 31, 2003
    Date of Patent: February 14, 2006
    Assignee: Aruze Corp.
    Inventors: Takao Nireki, Shingo Omono, Yuichiro Suzuki
  • Patent number: 6831432
    Abstract: Brake mode switching signal production means detects the number of revolutions per unit time of a rotor according to a change in a positional relationship between motor windings of a plurality of phases and the rotor so as to output first and second brake mode switching signals for selecting either a short brake mode or a reverse brake mode for braking the rotation of the rotor based on the number of revolutions. Control means outputs an energization control signal for controlling energization of the motor windings of a plurality of phases in response to the first and second brake mode switching signals. Thus, it is possible to reduce the braking noise and the stopping time.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: December 14, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Maki Murakami
  • Patent number: 6753668
    Abstract: A garage door drive assembly for moving a linkage arm connected to a garage door, the assembly being adapted for shipping in a partially assembled condition in at least a box for on-site installation, the assembly has a longitudinally-extending rail with laterally extending flanges. The assembly also has a carriage shaped to fit about the flanges. A drive mechanism is movably mounted to the rail. An anchor is coupled to the drive mechanism. The assembly also has a coupler with a selectively releasable connection to the anchor, a connector pivotably connectable to the linkage arm, and a detachable connection enabling the coupler to be fixedly secured to and carried by the carriage. The rail and the carriage may be shipped to the installation site in a box having a smaller cross-sectional profile than would be required to accommodate the carriage and coupling in their connected state.
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: June 22, 2004
    Assignee: Linear Corporation
    Inventors: James Patrick Stewart, Mark Y. Shin, Anthony Ramirez
  • Patent number: 6700340
    Abstract: A control circuit controls a coffee grinder having a grinder motor. The control circuit includes a timer portion and a first switch. The first switch functions as a two-condition switch to place the control circuit in one of (1) an off condition when the first switch is open and the timer portion and the grinder motor are de-energized and (2) a run condition when the first switch is closed, the timer portion is energized, and the grinder motor is energized once in the run condition, the control circuit remaining in the run condition until the timer portion times out or until the first switch is re-opened thereby returning the control circuit to the off condition.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: March 2, 2004
    Assignee: Hamilton Beach/Proctor-Silex, Inc.
    Inventors: Phillip Boyune Wong, Peter J. McCurdy
  • Publication number: 20040017294
    Abstract: A system and method for detecting user entry into a defined danger zone surrounding a saw blade includes a non-conducting member defining an opening therein for receiving a saw blade. The non-conducting member may comprise, for example, an insert received by an opening in the work surface or table of a table saw, scroll saw, band saw, miter saw, etc. Alternatively, it may comprise the blade guard of a radial arm saw or miter saw, for example. A conductive sensor is situated on the non-conducting member adjacent the opening to define a danger zone near the saw blade. A voltage source is coupled to the sensor, and a monitor circuit is configured to detect a change in the sensor's capacitance so as to signal a user entry into the danger zone.
    Type: Application
    Filed: July 29, 2002
    Publication date: January 29, 2004
    Inventor: James I. Metzger
  • Publication number: 20030178959
    Abstract: A control circuit controls a coffee grinder having a grinder motor. The control circuit includes a timer portion and a first switch. The first switch functions as a two-condition switch to place the control circuit in one of (1) an off condition when the first switch is open and the timer portion and the grinder motor are de-energized and (2) a run condition when the first switch is closed, the timer portion is energized, and the grinder motor is energized once in the run condition, the control circuit remaining in the run condition until the timer portion times out or until the first switch is re-opened thereby returning the control circuit to the off condition.
    Type: Application
    Filed: March 19, 2002
    Publication date: September 25, 2003
    Applicant: Hamilton Beach/Proctor-Silex, Inc.
    Inventors: Phillip Boyune Wong, Peter J. McCurdy
  • Publication number: 20030178961
    Abstract: The present invention relates to an electronic safety switching device having at least a first and a second signal processing channel. The channels can be supplied with input signals for signal processing, and they provide redundantly processed output signals. According to one aspect of the invention, the signal processing channels are arranged monolithically on a common semiconductor substrate. The semiconductor structures of each signal processing channel are spaced apart physically by a multiple of their width from the semiconductor structures of every other signal processing channel.
    Type: Application
    Filed: April 16, 2003
    Publication date: September 25, 2003
    Inventors: Roland Rupp, Hans Schwenkel
  • Publication number: 20030090224
    Abstract: A machine is disclosed having a detection subsystem adapted to detect contact between a person and a specified portion of the machine, and to distinguish that contact from contact with other materials. The detection subsystem imparts an electrical signal to a specified portion of the machine, and distinguishes that contact based on a predetermined frequency response of the electrical signal. A reaction subsystem then causes a predetermined action to take place. The machine may be a power saw designed to minimize injury in the event a person accidentally contacts the blade.
    Type: Application
    Filed: November 12, 2002
    Publication date: May 15, 2003
    Inventors: Stephen F. Gass, J. David Fulmer
  • Patent number: 6545444
    Abstract: A back EMF monopole motor and method using a rotor containing magnets all of the same polarity and in a monopole condition when in momentary apposition with a magnetized pole piece of a stator having the same polarity, said stator comprised of a coil with three windings: a power-coil winding, a trigger-coil winding, and a recovery-coil winding. The back EMF energy is rectified using a high voltage bridge, which transfers the back EMF energy to a high voltage capacitor for storage in a recovery battery. The stored energy can then be discharged across the recovery battery through the means of a contact rotor switch for further storage.
    Type: Grant
    Filed: March 13, 2001
    Date of Patent: April 8, 2003
    Assignee: Bedini Technology, Inc.
    Inventor: John C. Bedini
  • Patent number: 6498448
    Abstract: A motor brake releasing device includes an electromagnetic brake for locking a motor shaft and a switch mounted between the electromagnetic brake and a releasing-power-supply for the brake. The switch can be operated by an AND signal produced by a motor driving signal and a motor-brake-release-permitting signal. This structure allows a motor brake to be released when a motor driving system encounters an obstacle, although the motor is left free. The structure also can prevent a final object of the motor shaft from dropping due to its own weight.
    Type: Grant
    Filed: June 1, 2001
    Date of Patent: December 24, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Shigeru Shimogama
  • Patent number: 6456032
    Abstract: A motor driver for drive-controlling a brushless motor being provided with a delay circuit that detects the motor pulse. When a stop signal is inputted, a transistor is activated, which in turn activates an electric brake to brake the brushless motor, while at the same time, the motor pulse detected by the motor driver is inputted to the delay circuit. After the stop signal is inputted, the motor pulse declines, which is detected by the delay circuit to activate the electromagnetic brake. The delay circuit is provided on the driver substrate for the motor driver.
    Type: Grant
    Filed: November 29, 2000
    Date of Patent: September 24, 2002
    Assignee: Itoh Electric Co., Ltd.
    Inventors: Kazuo Itoh, Toshiyuki Tachibana, Shigeki Fukata
  • Patent number: 6291951
    Abstract: A holding brake control circuit is provided for use in conjunction with a servo-motor having an electrically operated holding brake. The holding brake has a pair of electric brake terminals and the brake is retained in a released condition as long as at least a preset brake voltage is maintained to the brake terminals. The holding brake control circuit includes a pair of output terminals connected to the electric brake terminals as well as a pair of power input terminals electrically connected to an electric power source. The electric power source, furthermore, has a higher voltage than the preset brake voltage. At least one capacitor is electrically connected in parallel with the input terminals so that the capacitor charges when power is applied to the input terminals. A voltage regulator has power inputs connected in parallel with the capacitor and a regulated voltage output connected in parallel with the output terminals for the control circuit.
    Type: Grant
    Filed: March 21, 2000
    Date of Patent: September 18, 2001
    Assignee: Valiant Machine & Tool Inc.
    Inventor: Dominique Baulier
  • Patent number: 6157153
    Abstract: A motor driver has a braking control circuit. The braking control circuit shuts off the supply of an electric current to the coils included in the motor when a motor control signal shifts to a predetermined level and, after a predetermined length of time secured in accordance with an index signal, starts application of braking to the rotation of the motor by the use of a braking circuit. The index signal is obtained from the signal that indicates the rotational position of the motor. The motor control signal is fed from a control signal generating circuit to the braking control circuit.
    Type: Grant
    Filed: April 9, 1999
    Date of Patent: December 5, 2000
    Assignees: Rohm Co., Ltd., Teac Corporation
    Inventors: Tomoaki Uegami, Takahiro Sakaguchi
  • Patent number: 6140784
    Abstract: A method and circuit for controlling a voice coil motor (VCM) for a disk drive actuator assembly such that the actuator assembly moves to a landing area at a constant velocity when the disk drive loses power. The circuit includes a sense amplifier for sensing and amplifying current to the VCM, a current integrator for determining the actual velocity of the actuator assembly during every seek, an H-bridge driver, which controls the direction of current to the VCM and magnitude of voltage across the VCM and a window compare and logic block that receives and sorts information from the integrator, and a timer. The window compare and logic block determines the direction of current and magnitude of voltage to apply to the VCM. During a loss of power, e.g.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: October 31, 2000
    Assignee: Quantum Corporation
    Inventor: Babak Mazda
  • Patent number: 6104153
    Abstract: A disk drive employs a method of operating a spindle motor to respond to a spin-down command to reduce the time required for spinning down and subsequently spinning up the spindle motor. The disk drive is connectable to a power supply having a fixed DC voltage. The spindle motor includes a stator having a plurality of windings and a rotor rotatable at a variable spin-rate. The rotor has an angular position relative to the stator. The disk drive includes switching elements coupled to the fixed DC voltage and the plurality of windings. The switching elements are controlled to sequentially apply the fixed DC voltage across a selected combination of the windings to generate a negative torque on the rotor such that a controlled braking operation is performed to decelerate the rotor to a selected spin-rate .omega.1. After the variable spin-rate is reduced to the selected spin-rate .omega.
    Type: Grant
    Filed: February 23, 1999
    Date of Patent: August 15, 2000
    Assignee: Western Digital Corporation
    Inventors: Raffi Codilian, Steven Nemshick, Robert P. Ryan
  • Patent number: 6046559
    Abstract: A motor control method stops rotation of a motor which rotates in a forward direction by applying a brake signal for rotating the motor in a reverse direction. The motor control method detects a power supply voltage, and corrects a brake signal applying time for which the brake signal is applied to the motor depending on the detected power supply voltage.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: April 4, 2000
    Assignee: Fujitsu Limited
    Inventor: Masaaki Iwasaki
  • Patent number: 6037728
    Abstract: A system for electrical braking and the storage for reuse of the braking energy is disclosed using alternating current (AC) rather than direct current (DC) generators coupled to the wheels of the vehicle to be braked. Upon braking, the AC generators feed the primary coil of a transformer whose secondary coil can be tapped at one of a number of different turns. Means are provided for changing the tap points so as to increase the number of turns in the secondary as the speed of the braked wheel declines. The output from the secondary is fed to a rectifier and thereafter the direct current is fed to a battery energy storage device. By increasing the turns of the secondary as the wheel speed drops, more energy can be fed and stored in the battery and the range of effective braking by the alternating current generator can be extended to lower speeds.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: March 14, 2000
    Inventor: Peter M. Petkovic
  • Patent number: 5894204
    Abstract: A spindle motor control method stops a spindle motor which rotates in a forward direction in response to a rotation signal. The spindle motor control method includes two steps. First, a brake signal is supplied to the spindle motor for rotating the spindle motor in a reverse direction when stopping the spindle motor which rotates in the forward direction. Second, the rotation signal and the brake signal are put in an OFF state when a frequency generator signal FG, which indicates a rotational phase of the spindle motor and is generated based on an output of the spindle motor, is not detected for a predetermined time.
    Type: Grant
    Filed: February 12, 1998
    Date of Patent: April 13, 1999
    Assignee: Fujitsu Limited
    Inventor: Hiroshi Kumita
  • Patent number: 5804940
    Abstract: A method for the numerical control of machines with several axes, in particular machine tools and robots, to compensate for the inaccuracies occurring when the axes are reversed, wherein varying friction conditions, as well as slackness and torsional effects are compensated using a friction precontrol. Rotation speed reference values are corrected by injecting a correction pulse with an acceleration-dependent injection amplitude and a constant decay time for each axis at the time of passage from one quadrant to another, with the associated change in direction. The injection amplitude and constant decay time are determined for each machine manually or learned in an additional embodiment automatically in a self-learning system in the form of a neural network.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: September 8, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventors: Friedrich Erkens, Stefan Maetschke, Bernd Quaschner
  • Patent number: 5760566
    Abstract: The invention relates to a control device for stopping the operation of a single-phase asynchronous motor with a capacitor in the event an overload of this motor with respect to a threshold value is detected. This device is characterized in that it includes, on the one hand, device for measuring the phase shift between any one parameter, voltage or current (U1, U2, I2, I3) of the main phase (.phi.1) or the secondary phase (.phi.2) and another one of these parameters and, on the other hand, device for controlling the stoppage capable of interrupting the current supply to the motor in the event there is measured a time delay lower than a memorized threshold value.
    Type: Grant
    Filed: January 27, 1997
    Date of Patent: June 2, 1998
    Assignee: Plumer, Societe Anonyme
    Inventors: Djafar Nassr, Philippe Raude, Louis Plumer
  • Patent number: 5712539
    Abstract: A system and method is provided for controlling a brushless DC motor (100), the motor being of the type having a plurality of coils (25, 26, 27) and a switching amplifier coil driving circuit (25A, 26A, 27A) including a plurality of transistors (21, 22, 29, 30, 33, 34). Current application to the plurality of transistors is controlled to obtain, near a commutation point of the motor, a simultaneous rise in current applied to a first of the transistors and a fall in current applied to a second of the transistors. Controlling application of current to the plurality of transistors involves, for each of the transistors, generating a PWM gate drive signal by selectively switching between a nominal PWM signal and a constant signal. The selective switching is in response to a synthesized state signal, the synthesized state signal being generated to alternate variably between the two states in accordance with a desired ramping of current to the first and second transistors.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 27, 1998
    Assignee: Exabyte Corporation
    Inventors: James Zweighaft, Mark H. Moyer, Christopher Koerner
  • Patent number: 5708339
    Abstract: A bag neck tying device for tying a ribbon dispensed from a spool about a gathered neck. A pulley and proximity switch are mounted to prevent the completion of a tying cycle if a bag neck is not properly gathered and ready to be tied.
    Type: Grant
    Filed: January 5, 1996
    Date of Patent: January 13, 1998
    Assignee: Burford Corporation
    Inventors: Jimmy R. Frazier, John D. Richardson, Greg P. Coxsey
  • Patent number: 5587640
    Abstract: A servomotor control system is set forth that assists in overcoming the problem of servomotor shut down during a failure of the programmable control system and/or servo-amplifier. The presently disclosed servomotor control system includes a programmable control system having one or more output signals connected to control a servo-amplifier. The system further includes a servomotor that is connected for control by the servo-amplifier. A safety switch is connected for detection by the programmable control system, the programmable control system controlling the servo-amplifier to brake the servomotor upon detection of the actuation of the safety switch. A delayed braking apparatus is disposed between the servo-amplifier and the servomotor. The delayed braking mechanism is also connected to detect the actuation of the safety switch, and acts to brake the servomotor after a predetermined time period from the detection of such actuation has lapsed.
    Type: Grant
    Filed: September 28, 1994
    Date of Patent: December 24, 1996
    Assignee: Tetra Laval Holdings & Finance S.A.
    Inventors: Anders Ek, Johan Hegardt
  • Patent number: 5495156
    Abstract: Method and apparatus for retracting an actuator comprising determining back emf voltage generated by the actuator motor; applying the determined voltage to a capacitor-resistor network; applying a holding voltage to the capacitor-resistor network. The application of the determined voltage and the holding voltage together charges a capacitor in the capacitor-resistor network to develop a charged capacitor voltage. The method and apparatus further comprises terminating application of the determined voltage to the capacitor-resistor network upon charging of the capacitor, and discharging the capacitor through the capacitor-resistor network to provide a forcing voltage to the actuator for retract operation. The forcing voltage initially forces a high deceleration current in the actuator. Further, the forcing voltage decays with time to a predetermined holding voltage to complete the retract operation.
    Type: Grant
    Filed: June 24, 1994
    Date of Patent: February 27, 1996
    Assignee: Quantum Corporation
    Inventors: Dean Wilson, Brian Molloy
  • Patent number: 5449992
    Abstract: A braking circuit for an electric motor includes a braking device for being connected in a circuit for braking the electric motor, a braking switch including first and second changeover switches for switching between a motor mode and a braking mode, and a control device. Switching contacts of the first and second changeover switches are switched between a first position for contacting, respectively, first stationary contacts of the first and second changeover switches in the motor mode, and a second position for contacting, respectively, second stationary contacts of the first and second changeover switches in the braking mode.
    Type: Grant
    Filed: September 24, 1993
    Date of Patent: September 12, 1995
    Assignee: Marquardt GmbH
    Inventors: August Geiger, Alexander Knappe, Michael Bufe