Van Truong

US Patent:

53270592, Jul 5, 1994

Filed:

Sep 24, 1992

Appl. No.:

7/950457

Inventors:

Van K. Truong - Harbor City CA
Edward H. Patrick - Westminster CA
David E. Woodral - Walnut CA

Assignee:

Archive Corporation - Costa Mesa CA

International Classification:

H02P 128
H02P 130

US Classification:

318632

Abstract:

A system and apparatus for startup and speed regulation of low-inertia capstan motors under circumstances where the capstan load during startup may vary widely. A stiction handler provides dynamic control of the motor drive voltage imposed to overcome stationary friction, minimizing the power consumption on startup independently of variations in drag load or motor inertia. A stepped speed-up signal is applied to the motor instead of a conventional constant current-limited signal or sawtooth ramp signal. Motor speed regulation is imposed at each step of a stepped speed-up drive signal. This invention is particularly useful, for example, in low-power magnetic tape drives that must efficiently adapt to variations in drag between one tape cassette or cartridge and another.