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| Number | Title | Issue Date |
| 7268502 | Method and arrangement for controlling the synchronous running of a plurality of electronically commutated motors A method of controlling synchronous running of a plurality of electronically commutated motors (22, 24, 26), each of which includes a stator having a stator winding (40, 42, 44), a permanent-magnet rotor (28, 30, 32), and at least one arrangemen... | 09/11/2007 |
| 7159479 | Active damper for stabilized mirrors An active damping method for a stabilized mirror, and a corresponding active damper apparatus, comprising providing a tachometer measuring speed of a motor driving the mirror, employing compensation electronics receiving input from said tachometer and the motor, and... | 01/09/2007 |
| 7088068 | Sensorless motor driving apparatus and driving method addressing prevention of backward rotation The sensorless motor driving apparatus according to the invention may include: a timing generation circuit generating a timing signal at intervals T; a driving signal generation circuit receiving the timing signal and generating, at the intervals T, pulse signals, t... | 08/08/2006 |
| 5675226 | Control circuit for an synchronous electric motor of the brushless type A control circuit comprises a TRIAC (T) in series with the stator winding (1) of the motor across the terminals of an alternating voltage source (VM). A fixed sensor (H) is associated with the rotor (R) and operable to provide a signal indicati... | 10/07/1997 |
| 5019755 | Electric motor drive system An electric motor drive system having a first electric motor, a first drive shaft to which the first electric motor is coupled, a second electric motor having a higher power rating than the first, a second drive shaft to which the second electric motor is... | 05/28/1991 |
| 4906908 | Method for numerical position control of motor-driven shafts In a method for numerical position control of motordriven shafts whose rotations are to be synchronous with one another under a certain transmission ratio a control loop is provided for each shaft. A speed setpoint, weighted with the corresponding transmi... | 03/06/1990 |
| 4492901 | Control system for synchronizing combination press line A control system for synchronizing a combination press line comprised of a transfer press and a double-action press. The transfer press is set as a master press and the double-action press as a slave press following the transfer press in operation. The transfe... | 01/08/1985 |
| 4334175 | Digital speed control method and apparatus 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 pres... | 06/08/1982 |
| 4264905 | Drive belt movement detecting system A belt movement sensor detects the movement of a belt having signal generating means embedded in or emplaced on the surface of a drive belt, and actuates a warning signal and/or controls the drive motor when the signal from the sensor varies by more than ... | 04/28/1981 |
| 4174237 | Process and apparatus for controlling the speed of web forming equipment 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 ... | 11/13/1979 |
| 4146824 | Low speed servo control A control system is described for use in a web transport in which a web is advanced from a supply spool to a take-up spool by a pair of drive motors, the latter of which are actuated by a servo control. The system includes a variable gain network which en... | 03/27/1979 |
| 4121138 | Servo system A system is described for controlling the speed and direction of rotation of first and second spools in a web transport system in which a web is advanced between the spools by first and second drive motors. The system incorporates a servo control which co... | 10/17/1978 |
| 4095146 | Reel-to-reel drive with speed control Long and short term variations in the speed at which a magnetic tape is moved with respect to a read and/or write head are minimized by maintaining the product of the speed of the tape payout and take-up reels constant. In accordance with a preferred embo... | 06/13/1978 |
| 4092576 | Method and apparatus for facsimile scanning A facsimile transceiver comprises a rotatably mounted drum and an information transducer juxtaposed to the drum for marking on a copy medium carried by the drum or detecting dark-light variations in a document carried by the drum. The drum is driven by a ... | 05/30/1978 |
| 4075538 | Adaptive acceleration responsive system A method and apparatus for rapidly detecting acceleration variations in a moving object by monitoring the instantaneous velocity of the object. A signal representative of instantaneous velocity is operated on to derive signals representative of average ac... | 02/21/1978 |
| 4051415 | Web speed control system A motor control system for use in maintaining substantially constant linear speed of a web moving between a supply and a takeup reel such as in a reel driven magnetic tape transport. The rotational periods of the reels are measured to provide representati... | 09/27/1977 |
| 4000449 | Electrical shaft system Two movable members driven by individual motors are positioned accurately at any given time and are tracking each other for all displacements. Individual positioning is used with differential positioning to force a follow-up of one member relative to the ... | 12/28/1976 |
| 3989989 | Conveyor overspeed-underspeed and/or slip detector A control system is provided for stopping the operation of a bulk material conveyor system in response to an indication that the speed of either drive or driven elements thereof are above or below acceptable amounts, that the output speed of a particular ... | 11/02/1976 |
