Patents Examined by R. Rudy
  • Patent number: 5149998
    Abstract: A dynamic braking means for a variable speed dynamoelectric eddy current drive consists of an ac motor (4) rotationally coupled through a shaft (6) to an inductor drum assembly (13) of an eddy current coupling (3), where an annular field coil 12 generates an electromagnetic field which couples the inductor drum assembly to a pole assembly (10) which is rotationally coupled to an output shaft (16) which drives an inertial load (20). Upon command to stop and brake, a controller (30) signals a motor switch (26) to disconnect the ac motor from the ac source and connect it to a dc source, causing a braking torque to be produced. Concurrently, the controller signals a coupling switch (28) to go to an open position momentarily until the motor decelerates to approximately zero speed, whereupon the coupling switch is again closed, coupling the inertial load to the motor, thereby providing a braking action.
    Type: Grant
    Filed: August 23, 1991
    Date of Patent: September 22, 1992
    Assignee: Eaton Corporation
    Inventor: John H. Wolcott