Diverse Speeds For Different Motors Patents (Class 318/67)
  • Patent number: 5712543
    Abstract: An apparatus for controlling a surgical device includes a housing and a magnetic switching element mounted on the housing. The magnetic switching element includes a magnet, a magnetic sensor configured to produce a control signal for controlling the surgical device, and an actuator mounted on the housing for movement between a first position in which a magnetic field of the magnet is decoupled from the magnetic sensor and a second position in which the magnetic field is coupled to the magnetic sensor so as to change a value of the control signal produced by the magnetic sensor. The magnetic switching element may also include magnetically soft material positioned so that movement of the actuator causes relative movement between the magnet and the magnetically soft material.
    Type: Grant
    Filed: April 10, 1996
    Date of Patent: January 27, 1998
    Assignee: Smith & Nephew Endoscopy Inc.
    Inventor: Douglas D. Sjostrom
  • Patent number: 5705908
    Abstract: A drive unit capable of maintaining the stability of driving speed with respect to the driven part in which the motor is not used at a low drive efficiency.
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: January 6, 1998
    Assignee: NEC Corporation
    Inventor: Hideo Kashimura
  • Patent number: 5638387
    Abstract: A lift truck has a tractive-power electric motor, an electric motor which actuates a pump for the hydraulic circuits, and batteries which supply the electric motors. In order to obtain a long working life as well as reliability and a high performance, the tractive-power motor or both motors are asynchronous and there are provided devices for sensing the angular positions and angular velocities of the motors and an electronic control unit connected to the sensor devices for controlling the power supplies to the motors in dependence on required velocities for the motors and on the basis of data provided by the sensor devices.
    Type: Grant
    Filed: January 10, 1995
    Date of Patent: June 10, 1997
    Assignee: Fiat Om Carrelli Elevatori S.p.A.
    Inventors: Guido Palleggi, Fabrizio Lanza
  • Patent number: 5627438
    Abstract: A pulsing drive system delivers pulsed power signal of the driven wheels of a vehicle for improving the efficiency internal combustion or an electric motor driven vehicles. A controller receives signals such as velocity and demand, and communicates to a means for selectively communicating energy wherein the means for selectively communicating energy converts the pulse signal to a correspondingly conditioned power pulse for powering the vehicle. When combined with a plurality of motors sized with optimal horsepower ranges according to a binary array, an arrangement of such motors provides for an optimally efficient operation of the vehicle by bringing on-line strategically selected combinations of the motors. A control system selectively brings on-line the multiple motors.
    Type: Grant
    Filed: January 25, 1995
    Date of Patent: May 6, 1997
    Inventor: Robert D. Barrett
  • Patent number: 5606231
    Abstract: A vibrating table for compaction of a mass such as concrete. The vibrating table includes a table top adapted to support the mass to be compacted. Support members support the table top above a floor and provide the table top with two degrees of freedom of movement in a principal plane which is substantially horizontal. The support members rigidly support the table top against movement in a generally vertical direction. An excitation shaft is coupled to the table top and has an axis of rotation which is generally perpendicular to the horizontal principal plane. The excitation shaft includes an unbalanced mass for the creation of an excitation force which provides movement of the table top in the horizontal principal plane.
    Type: Grant
    Filed: December 2, 1994
    Date of Patent: February 25, 1997
    Assignee: Netter GmbH
    Inventors: Dietrich Kroger, Arnim Bura
  • Patent number: 5528114
    Abstract: Plural systems of switching signals are obtained from a single microprocessor for driving a plurality of motors and other apparatuses while achieving effective use of ports of the microprocessor. In principle, three kinds of switching signals based on three-phase are generated in the microprocessor, the three kind of switching signals are converted to six kinds of switching signals in circuits external to the microprocessor, and then the signals are supplied to their respective switching elements in an inverter circuit.
    Type: Grant
    Filed: November 10, 1993
    Date of Patent: June 18, 1996
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hisashi Tokizaki, Naoto Tsukui
  • Patent number: 5487437
    Abstract: A turning control system for an electric vehicle includes a differential filter which receives a signal indicative of a desired vehicle steer angle and generates a pair of signals representative of proportional speed and direction at a left and a right drive wheel of the vehicle. Speed limit factors generated by an angular speed limit filter and an operator set throttle control are applied to the signals indicative of proportional speeds to generate desired proportional speed signals. The desired proportional speed signals are applied to a motor coupling controller along with signals indicating the actual motor speeds.
    Type: Grant
    Filed: March 7, 1994
    Date of Patent: January 30, 1996
    Inventor: Isaac Avitan
  • Patent number: 5345154
    Abstract: A heat engine operates an alternator that supplies electrical power to an electric continuously variable transmission for driving at least one ac motor through a differential to multiple wheels or to multiple independent ac wheel motors in an automobile, bus or truck. A heat engine control operates in a closed-loop power mode and decouples heat engine speed from motor speed, allowing the heat engine to produce required power at an operating speed and throttle position, or fuel injector duty cycle, that maximizes fuel economy and minimizes engine emissions. An energy storage unit (e.g., a battery, flywheel, ultracapacitor, superconducting magnetic energy storage device, or combination thereof) provides electrical energy to the electric drive system during vehicle accelerations and further reduces peak power demands on the heat engine. Advantageously, energy is recovered during vehicle deceleration and braking; and the recovered energy is used to recharge the energy storage unit.
    Type: Grant
    Filed: February 26, 1993
    Date of Patent: September 6, 1994
    Assignee: General Electric Company
    Inventor: Robert D. King
  • Patent number: 5248922
    Abstract: A motion controller, which is adaptable to a variety of different motors, provides motor control signals to the motors of a multi-axis coordinated system as a function of position and velocity commands from a host computer. The motion controller configures the motor control signals to be compatible to the particular motors being driven based upon motor identification instructions from the host computer.
    Type: Grant
    Filed: April 27, 1992
    Date of Patent: September 28, 1993
    Assignee: Motion Control Technologies, Inc.
    Inventor: Saeid Meshkat
  • Patent number: 5239247
    Abstract: A machine control permits the selection of input values defining configurations of motors on the machine in desired master-slave relationships. Individual master-slave dependencies may be selectively activated and deactivated. In response to a new commanded velocity for a master motor the control is effective to alter the velocities of all motors dependent therefrom as a function of change of velocity of the master motor and selectable slave ratios.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: August 24, 1993
    Assignee: Cincinnati Milacron
    Inventors: Thomas F. Habig, Ronald M. Sparer
  • Patent number: 5239245
    Abstract: A method of controlling the rotational speeds and phases of drum and capstan motors forming part of a servo system in a VCR by detecting signals that correspond to current rotational speeds and phases of the motors, and controlling the rotational speeds and phases of the motors by using the detected signals in rotational speed control and phase control routines. The speed control routine applys the steps of: inputting current rotational speed signals; producing rotational speed control signals corresponding to a rotational speed error signal; applying the produced rotational speed control signals to the drum and capstan motors to control their rotational speeds, performing a compensating operation necessary to the servo system, and then completing the rotational speed control routine.
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: August 24, 1993
    Assignee: Gold Star Co., Ltd.
    Inventor: Hong S. Lee
  • Patent number: 5237250
    Abstract: A multiplexor circuit connects a plurality of stepper motors to a lesser number of stepper motor drivers with at least one driver connected to a plurality of parallel connected stepper motors. A control computer through a multi-axis position controller generates step commands to the drivers to move one or more stepper motors a predetermined amount, at a predetermined speed and in a predetermined direction of rotation. The computer configures switches in the multiplexor circuit to connect selected ones of the stepper motors to selected drivers such that a plurality of stepper motors may be connected in parallel to a single driver such that a single driver can sequentially drive multiple stepper motors thereby reducing the number of drivers required for a plurality of stepper motors.
    Type: Grant
    Filed: November 1, 1991
    Date of Patent: August 17, 1993
    Inventors: Kim A. Zeile, James F. Runstrom
  • Patent number: 5198736
    Abstract: A technique of this invention discloses an orthogonal two-axis moving apparatus basically adapted to move in horizontal and vertical directions. In one embodiment the apparatus includes a vertical block, a horizontal moving member movably supported on the vertical block, and a driving mechanism for moving the horizontal moving member, a driving pulley, a driven pulley, and a belt for transmitting a driving force.
    Type: Grant
    Filed: November 13, 1991
    Date of Patent: March 30, 1993
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yusaku Azuma, Katsumi Ishihara, Takeo Tanita, Hiroyuki Kigami
  • Patent number: 5191267
    Abstract: A spiral drum freezer apparatus having a system for measuring and monitoring the "overdrive" of a rotated drum relative to a spiral belt helically wrapped around the drum in an ascending fashion. The system measures overdrive directly and continuously by obtaining a first speed measurement of the drum directly from the sprockets of a drive gear box drivingly engaging the drum. An alternative point of measurement for measuring rotational speed includes proximate the sprockets of a drum wheel driven by a belt, or sensing spaced-apart vertical outer structure members of the drum. Another point yet is on a disc-like plate. This plate is coaxially aligned and attached to the drum, and has precisionally spaced apart markings proximate a periphery where the rotational speed of the plate is directly proportional to the rotational speed of the drum. A second speed measurement is obtained by measuring the rotational speed of sprockets of a guide roller guiding the spiral belt.
    Type: Grant
    Filed: February 20, 1992
    Date of Patent: March 2, 1993
    Inventor: David G. Machacek
  • Patent number: 5117163
    Abstract: A drive system with slip control for railway vehicles with two or more dc drive motors and with common control of the motor armature currents and a logic unit to which are input a measured signal which indicates the armature current intensity of the motor driving the axle having the best adhesion which is usually the trailing axle motor. The measured signal and an amplification signal are multiplied by each other and the product signal issued in a feedback loadsharing system to control the other motors such that the torque of the other motors increased to a maximum allowed level, the trailing axle then rolling very close to ground speed without slipping. This speed is used as a measure of the true speed, which in turn controls the system for loadsharing such that the vehicle can be controlled to maximum tractive effort without causing slipping axles.
    Type: Grant
    Filed: October 19, 1990
    Date of Patent: May 26, 1992
    Assignee: Asea Brown Boveri AB
    Inventor: Lennart Sandberg
  • Patent number: 5077506
    Abstract: An apparatus for controlling the speed of a plurality of DC motors, comprises a device for supplying voltage to one of the plurality of DC motors, first selector for selecting one of the DC motors to be connected to the device for supplying voltage, second selector for selecting a desired speed for the selected DC motor, a device for producing a feedback signal representative of an electrical current drawn by the selected DC motor and a controller for: (i) producing a reference voltage in response to the first and second selectors (ii) producing a load voltage in response to the feedback signal and (iii) outputting a control signal which is the sum of the reference voltage and the load voltage to the device for supplying voltage so that the selected DC motor is operated at the desired speed.
    Type: Grant
    Filed: February 3, 1989
    Date of Patent: December 31, 1991
    Assignee: Dyonics, Inc.
    Inventor: Kenneth W. Krause
  • Patent number: 5063334
    Abstract: An orthogonal two-axis moving apparatus includes a first guide member which extends along one direction and is attached to a stationary position, a slide block which is slidably supported on the first guide member and is movable in the one direction, and a second guide member which extends along the other direction perpendicular to the one direction and is supported by the slide block to be movable in the other direction. First and second rollers are pivotally supported on two ends of the first guide member, a third roller is pivotally supported on one end of the second guide member, and intermediate rollers are pivotally supported on four corner portions of the slide block. A coupling belt is provided and has two ends of which are fixed to the other end of the second guide member and which is looped in a cross shape on the first to third rollers and the four intermediate rollers.
    Type: Grant
    Filed: July 23, 1990
    Date of Patent: November 5, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takeo Tanita, Hiroyuki Kigami, Yusaku Azuma
  • Patent number: 5013981
    Abstract: Control arrangement for an electric motor having a control arrangement which, in accordance with at least one nominal value fed thereto, controls at least one power control element to be connected to an electrical network and the motor, including data transmission apparatus in the form of a computer device for applying to the control arrangement data received by the computer device from at least one of a device for determining the data and a memory wherein the data are stored.
    Type: Grant
    Filed: May 18, 1989
    Date of Patent: May 7, 1991
    Assignee: Heidelberger Druckmaschinen AG
    Inventor: Anton Rodi
  • Patent number: 4956589
    Abstract: A work station having a plurality of tools permits selection, operation and speed control of individually selected tools using a common speed control for each tool. Each of the tools includes a tool head such as a cutter, rasp, or other forming or finishing tool supported at the end of a flexible drive shaft rotatable by a motor. A free end portion of the drive shaft includes a holding portion to permit manipulation of the tool but by an operator. A set of berths is located at the work surface with each berth configured to receive respective end portions of the drive shafts. A switch is provided in each berth for electrically connecting each of the motors to the common speed control which is operable by a foot pedal for controlling the speed of a selected tool. Under this arrangement, an operator at the work station can manipulate any one of the work tools without the burden of manipulating the tool speed which is pedal controlled.
    Type: Grant
    Filed: December 12, 1988
    Date of Patent: September 11, 1990
    Inventor: Victor M. Cherlo
  • Patent number: 4922173
    Abstract: A drive system for a machine such as a robot providing motion in two independent directions under the control of respective motors, comprising a saddle supported for motion in a first said direction, an arm supported by said saddle for motion in the second said direction, a first belt drive arranged to transmit drive from a first of said motors to said saddle and a second belt drive arranged to transmit drive from the second of said motors to said arm, said second belt drive comprising a belt having two portions extending around respective pulleys mounted on the arm and arranged to be driven by the second motor such that one portion is lengthened and the other shortened when the first motor is stopped, so that the arm moves relative to the saddle, but when the first motor is driven and the second motor stopped said two portions remain the same length so that the arm does not move relative to the saddle as the saddle moves.
    Type: Grant
    Filed: September 23, 1988
    Date of Patent: May 1, 1990
    Assignee: The Kemble Instrument Company Limited
    Inventor: Anthony J. Lawler
  • Patent number: 4866354
    Abstract: In spiral drum freezer apparatus having an insulated disclosure a spiral drum is mounted for rotation within the enclosure and includes a spiral belt to the spiral drum with the top of the spiral drum being supported by UHMW bearings and the bottom of the spiral drum being supported by a planetary wheel drive. A gear motor is connected to the planetary wheel drive for rotating the spiral drum at a specified speed. A take-up drive gear motor drives the spiral belt. A tachometer feedback speed control sense the speed of the drum gear motor and controls the speed thereof and the take-up drive gear motor in accordance with the preselectable speed.
    Type: Grant
    Filed: April 25, 1988
    Date of Patent: September 12, 1989
    Assignee: Refrigeration Engineering Corporation
    Inventor: David B. Miller
  • Patent number: 4829217
    Abstract: A safety device for use in a recording apparatus controls the on/off operation and prevents the malfunction of motors for driving a gear flange to rotate a light sensitive drum and for driving an actuating gear and other driving members in accordance with a signal indicative of the reference rotational frequency received from an oscillator and a signal indicative of the rotational frequency of each motor. A motor control circuit is used including motor drivers for controlling the operation of said motors and a fault detection circuit for detecting the malfunction of said motors by comparing an adder output indicative of said motors' rotational frequencies with threshold values in a comparator, thereby ascertaining the long-term use of the light sensitive drum.
    Type: Grant
    Filed: April 28, 1986
    Date of Patent: May 9, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toru Kameyama, Ken Miyagi
  • Patent number: 4746264
    Abstract: An earth-working machine includes a first internal gear fixedly mounted on a mobile chassis, a turntable coaxially rotatably mounted on the first internal gear, a carriage rotatably mounted on the turntable in eccentric relation thereto and having a second internal gear, an earth-working mechanism mounted on the carriage, a first hydraulic motor mounted on the turntable and having a first pinion held in driving mesh with the first internal gear for rotating the turntable about its own axis, a second hydraulic motor mounted on the turntable and having a second pinion held in driving mesh with the second internal gear for rotating the carriage about its own axis, and hydraulic driving devices for actuating the first and second hydraulic motors independently or in synchronism. The hydraulic driving devices may be controlled by an electric control system supplied with signals from angle detectors such as rotary encoders for detecting angular displacements of the turntable and the carriage.
    Type: Grant
    Filed: October 16, 1986
    Date of Patent: May 24, 1988
    Assignee: Kabushiki Kaisha Hikoma Seisakusho
    Inventors: Mitsuhiro Kishi, Yokichi Nagasawa
  • Patent number: 4661714
    Abstract: An AC marine propulsion system which provides a constant continuous rated horsepower availability at the standard rated engine RPM, over the full useful operating range of the propeller. A prime mover diesel engine is operated at its continuous rated speed to provide for maximum fuel efficiency. An alternator connected to the prime mover is driven at a speed which is higher than the standard rated alternator speed, thus producing higher than standard rated voltage and frequency. The combination of prime mover and alternator provides for an optimum system mass to power ratio. An AC motor is coupled through a gearbox to a fixed pitch propeller system. A frequency converter is dispsoed between the alternator and AC motor. Propeller RPM is controlled by changing the frequency of the voltage supplied to the AC motor.
    Type: Grant
    Filed: June 17, 1985
    Date of Patent: April 28, 1987
    Inventors: J. Glenn Satterthwaite, George B. Field, Jr.
  • Patent number: 4647824
    Abstract: In a system having a plurality of electric motors which are rated at different voltages, a voltage control circuit enables the electric motors to be connected to a common power supply. The voltage control circuit determines a first voltage appearing between the positive bus of the power supply and the motor and a second voltage appearing between the negative bus and the motor. One voltage is inverted and then summed with the non-inverted voltage to provide an average voltage. The average voltage is compared to a reference voltage and when the average voltage exceeds the reference voltage, a limit signal is generated. The limit signal is used to prevent higher voltages from being applied across the motor.
    Type: Grant
    Filed: April 19, 1985
    Date of Patent: March 3, 1987
    Assignee: Kollmorgen Technologies Corp.
    Inventor: Rolf Eichenwald
  • Patent number: 4511825
    Abstract: The electric wheelchair includes a battery pack (A), a right drive motor (B), a left drive motor (C), and a control circuit for controlling the amount of power supplied from the battery to the left and right control motors. A speed potentiometer (24) and a direction potentiometer (26) are connected with a joystick (22) for producing a selected vehicle speed signal and a selected vehicle direction signal, respectively. A right speed control circuit (E) and a left speed control circuit (F) receive the selected vehicle speed and direction signals and control the right and left motors in accordance with them. Each speed control circuit includes a reference signal circuit (90) which receives the selected vehicle speed and direction signals and produces a reference signal whose magnitude varies with the speed selected for its motor. The voltage and current across the armature of the motor are detected as measures of the motors actual speed.
    Type: Grant
    Filed: February 24, 1982
    Date of Patent: April 16, 1985
    Assignee: Invacare Corporation
    Inventor: Robert G. Klimo
  • Patent number: 4507044
    Abstract: A compact robot of the 3-axis type comprising a base-mounted motor control system with means to sense the position of a robot arm through a servo-system comprising position-sensing potentiometers mounted in the motor control system and a feed-back control system to co-ordinate the vertical and horizontal movement of a robot arm.
    Type: Grant
    Filed: December 8, 1981
    Date of Patent: March 26, 1985
    Assignee: Zymark Corporation
    Inventors: Burleigh M. Hutchins, Raymond R. Dunlap, Louis Abrahams
  • Patent number: 4506197
    Abstract: This invention concerns a method of controlling mill-motor speed in a cold tandem mill. During unsteady phases of rolling operation such as threading, rolling speed acceleration and/or deceleration, and tail out with respect to the coil being rolled, mill motors are so controlled as not to perform drooping characteristic action except under certain specific conditions, and at threading phase in particular, motors in individual stands are so controlled as to revolve at a uniformly decreased speed, whereby final gauge control accuracy can be improved with respect to top and bottom end portions of the coil and such troubles as coil cut and the like can be effectively prevented.
    Type: Grant
    Filed: January 30, 1984
    Date of Patent: March 19, 1985
    Assignee: Sumitomo Kinzoku Kogyo Kabushiki Kaisha
    Inventors: Katsuya Kondo, Shigeru Tajima
  • Patent number: 4471273
    Abstract: The invention pertains to a control circuit (10) for controlling the speed of a pair of motors (12,14), including a pair of switching elements (68,74) coupling power to the motors (12,14), a pair of controllable circuits (64,74) for driving the switching elements (68, 74), a circuit (36) for generating digital numbers representing the same command speed for each of the motors (12,14), a circuit (38) for generating digital numbers representing differential command speeds for the motors (12,14), and a data processor (56) for controlling the pair of controllable circuits (64,74) in response to the digital numbers. By utilizing digital and integrated circuit technology, prior, essentially linear, control apparatus, which are relatively unreliable, expensive and slow, need not be used.
    Type: Grant
    Filed: January 5, 1983
    Date of Patent: September 11, 1984
    Assignee: Towmotor Corporation
    Inventors: Grant C. Melocik, William Pickering
  • Patent number: 4460852
    Abstract: This invention concerns a method of controlling mill-motor speed in a cold tandem mill. During unsteady phases of rolling operation such as threading, rolling speed acceleration and/or deceleration, and tail out with respect to the coil being rolled, mill motors are so controlled as not to perform drooping characteristic action except under certain specific conditions, and at threading phase in particular, motors in individual stands are so controlled as to revolve at a uniformly decreased speed, whereby final gauge control accuracy can be improved with respect to top and bottom end portions of the coil and such troubles as coil cut and the like can be effectively prevented.
    Type: Grant
    Filed: January 29, 1982
    Date of Patent: July 17, 1984
    Assignee: Sumitomo Kinzoku Kogyo Kabushiki Gaisha
    Inventors: Katsuya Kondo, Shigeru Tajima
  • Patent number: 4415049
    Abstract: An electric control is disclosed for an electrically powered vehicle having independently controlled left and right drive motors and associated drive wheels to propel and steer the vehicle. The electrical control includes left and right closed loop control circuits for respectively accelerating either or both of the drive wheels whenever a speed command or error signal associated with such drive wheel exceeds a first determined value. Dynamic braking is provided by connecting in parallel electrical relationship an associated brake resistor across one or both of the motors whenever the speed command signal associated with such motor does not exceed a second predetermined value.
    Type: Grant
    Filed: September 14, 1981
    Date of Patent: November 15, 1983
    Assignee: Instrument Components Co., Inc.
    Inventor: John A. Wereb
  • Patent number: 4341982
    Abstract: A system for simultaneously and independently controlling a plurality of electric motors from a number of dispersed stations. The system operates by transmission of duty cycle modulated selected frequencies superimposed on a DC track voltage on a common power line servicing the motors. The modulation is variable and determines the speed of the motors. Transmitters are portable and designed removably to plug into a common signal transmission cable anywhere along its length without interaction. Receivers, each tuned to a specific frequency and associated with and controlling a motor, are coupled to the common power line.
    Type: Grant
    Filed: July 3, 1980
    Date of Patent: July 27, 1982
    Assignee: Power Systems, Inc.
    Inventors: Abbott W. Lahti, Stephen R. Russell
  • Patent number: 4334175
    Abstract: In a speed control method for digitally controlling the speeds of motors in a sectional drive system including the steps of setting a speed difference of each section with respect to a line speed reference, the speed difference set value is varied by pressing a push button switch and varying the speed difference set value by a unit value every unit operation time when the button switch is pressed.
    Type: Grant
    Filed: June 29, 1979
    Date of Patent: June 8, 1982
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Hiroichiro Tanaka, Yasuo Nagatani
  • Patent number: 4296361
    Abstract: A motor control system for a pair of motors which drive respective wheels of a vehicle which is steered by controlling the relative speed of the motors includes switch means, and a pair of resistors which are connected in a series circuit including the motors, when no current is being supplied to the motors in order to provide electrical braking of the motors.
    Type: Grant
    Filed: July 24, 1979
    Date of Patent: October 20, 1981
    Assignee: Lucas Industries Limited
    Inventor: Michael A. Archer
  • Patent number: 4284929
    Abstract: Control circuitry for producing signals to control motors which propel a ile platform for a standing paraplegic. Logic circuits connect a 3-axis joy stick controller to four permanent magnet DC motors mounted on the platform such that the platform follows in the direction of the displacement of the joy stick. The joy stick outputs are taken as inputs to several differential amplifiers. Each of a plurality of velocity servo amplifiers receives one input signal from the differential amplifier output and another from a tachometer feedback signal derived from each motor. Comparators receive the velocity servo amplifier outputs as well as a triangular wave input. Each comparator comprises a pulse width modulator which generates pulse outputs whose duty cycle is a function of the voltage inputs to each comparator. The comparator outputs then control motor rotation such that the platform moves in the direction of displacement of the joy stick.
    Type: Grant
    Filed: October 27, 1978
    Date of Patent: August 18, 1981
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Robert A. Garrett, John Silva, Craig R. Allen
  • Patent number: 4270072
    Abstract: A cable extending onto a drum-cutter loader mining machine has divided branch cable sections to supply electrical current to the individual drive motors for each of two cutting drums. A branch switch coupled in each divided branch cable section and a thyristor controller is coupled in one branch cable section before the switch therein. Crossover lines bridge the branch switches in each divided branch cable section. Bridge switches in each of the bridging crossover lines are used together with the branch switches to deliver electrical current from the controller to either or, if desired, both of the separate drive motors.
    Type: Grant
    Filed: January 18, 1979
    Date of Patent: May 26, 1981
    Assignee: Gebr. Eickhoff Maschinenfabrik und Eisengeisserei m.b.H.
    Inventor: Karl-Heinz Weber
  • Patent number: 4259621
    Abstract: A speed regulator for a guide and follower motor assembly. A guide pulse frequency generator driven by a guide motor drives a frequency converter which drives a follower motor. The frequency converter includes a frequency regulator with a negative feed back which includes a frequency divider. Adjusting and setting circuits for the frequency divider include an up/down counter for operating the frequency divider, a resetting operation of the counter to provide a frequency indicating value for its output, an adjustable pulse generator for driving the counter, an add/subtract circuit, and a comparator responsive to the add/subtract circuit and the counter to control the pulse generator.
    Type: Grant
    Filed: August 31, 1978
    Date of Patent: March 31, 1981
    Assignee: Danfoss A/S
    Inventors: Jakob S. Jakobsen, Robert M. McCulloch
  • Patent number: 4174237
    Abstract: A speed control system is provided for apparatus and process for shaping and treating web material of indefinite length wherein the apparatus includes a master processing unit, one or more slave processing units communicating with the master unit through web storage or buffer means and a computer. Information as to the desired speed and mode of operation of the master unit and the mode of operation of the slave units is inputted to the computer which communicates with the drive motors of the master and slave units through special buffered isolated amplifiers and automatically controls the speed of the slave units so as to maintain the desired quantity of partially processed web material in the web storage means and to maintain the selected operating speed of the master unit.
    Type: Grant
    Filed: July 3, 1978
    Date of Patent: November 13, 1979
    Assignee: International Paper Company
    Inventors: Frank E. Hemming, Jr., Stuart A. Johnson
  • Patent number: 4166238
    Abstract: A control system for a dual-wheel drive which includes two drive motors independently controllable by regulating the amount of current which flows to each of the motors. Two contact means are provided wherein one is a rotatable wiper arm system and the other is a pivotable plate system. A control motor continuously moves one of these two contacts while a drive wheel selectively moves the other contact. One of the contacts serves as a common electrical supply terminal for both of the drive motors while the other contact has separate terminals respectively coupled to each of the two drive motors to supply them with current. The contact relationships between the two contacts are selectively controlled by means of the drive wheel whereby the amount of current directed to flow in each of the two motors is controlled.
    Type: Grant
    Filed: October 27, 1977
    Date of Patent: August 28, 1979
    Inventor: Tihamer S. Binner
  • Patent number: 4093896
    Abstract: Disclosed herein is a control comprising a rotatably supported wheel, a first direct current motor, means drivingly connecting the first direct current motor to the wheel with a first drive ratio, a second direct current motor, means drivingly connecting the second direct current motor to the wheel with a second drive ratio lower than the first drive ratio, a source of direct current, and a switch electrically connected to the source of direct current and to the first and second direct current motors and including a contact arm for initially electrically connecting the direct current source to the first direct current motor whereby to drive the wheel at a slow speed, and for subsequently additionally electrically connecting the source of direct current to the second direct current motor while maintaining electrical connection of the direct current source to the first direct current motor, whereby to drive the wheel at a fast speed.
    Type: Grant
    Filed: August 11, 1976
    Date of Patent: June 6, 1978
    Assignee: Outboard Marine Corporation
    Inventor: Gerald N. McAuliffe
  • Patent number: 4086903
    Abstract: A tennis ball throwing machine for use in the practice of tennis having the capability of controllably delivering tennis balls to a player's forehand and backhand at various speeds and with various spins simulating conditions commonly encountered in game play. The machine has a pair of wheels which are independently and controllably driven so as to throw a tennis ball delivered therebetween by an automatic ball feed mechanism at a speed and with a spin determined by the speed of each of the wheels. Various features include an oscillating system to alternate pitches between the forehand and backhand in a controllable manner, an elevation adjustment mechanism for controllably varying the height of the delivery or providing a random variation in such height, and independent ball speed and ball spin controls. Remote controls for the machine may be provided.
    Type: Grant
    Filed: April 13, 1976
    Date of Patent: May 2, 1978
    Inventor: Jack C. Scott
  • Patent number: 4017774
    Abstract: A method for coordinating the rate of processing of a container at a processing station with the rate of feed of said container to and removal from said processing station, comprising selecting a predetermined rate for said processing and said feed and removal, independently and continuously comparing the actual processing rate with said selected rate, independently and continuously comparing the actual feed and removal rate with said selected rate, and independently adjusting the actual rate of processing and the actual rate of feed and removal as needed to arrive at said selected rate. A corresponding apparatus is described wherein the speed selecting means includes a potentiometer. A pair of tachogenerators respond independently to the actual speeds of processing and conveying and these are independently electronically compared with the selected speed established by the potentiometer, the driving speeds being independently adjusted as needed in response to the comparisons.
    Type: Grant
    Filed: May 30, 1975
    Date of Patent: April 12, 1977
    Assignee: Jagenberg Werke AG
    Inventor: Rainer Buchholz
  • Patent number: 3970160
    Abstract: A steering control for an electrically powered vehicle having a pair of traction wheels on each side of the vehicle's frame, each of said wheels being driven by a synchronous type motor. The rotor field producing coils of each motor being separately controlled by the accelerator control of the vehicle and a frequency changing circuit which selectively changes the rotational speed of individual motors. The frequency changing circuit includes frequency divider switches and frequency counters connected to the rotor field producing coils; the wipers of said frequency divider switches are connected to the steering control in such manner as the output of each frequency dividing counter is varied independently. A battery included in such vehicle for producing electric power needed for the motors can be charged by a generator or alternator.
    Type: Grant
    Filed: November 6, 1973
    Date of Patent: July 20, 1976
    Inventor: William Nowick
  • Patent number: RE30356
    Abstract: .Iadd.A hand drill includes an induction motor energized by a multi-phase electrical power source with the angle between consecutive phase maintained substantially constant over a wide frequency range by energizing logical circuitry comprising a number of flip-flops intercoupled by AND GATES. .Iaddend.
    Type: Grant
    Filed: June 16, 1978
    Date of Patent: August 5, 1980
    Inventors: Herbert Berman, Harvey L. Pastan
  • Patent number: RE32414
    Abstract: A compact robot of the 3-axis type comprising a base-mounted motor control system with means to sense the position of a robot arm through a servo-system comprising position-sensing potentiometers mounted in the motor control system and a feed-back control system to co-ordinate the vertical and horizontal movement of a robot arm.
    Type: Grant
    Filed: February 7, 1986
    Date of Patent: May 12, 1987
    Assignee: Zymark Corporation
    Inventors: Burleigh M. Hutchins, Raymond R. Dunlap, Louis Abrahams