The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 09, 1988
Filed:
May. 17, 1982
John J Neesz, Rochester, MN (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
The circuit provides damping for digitally controlled devices where the provision of power pulses in response to sensing a given device parameter may result in a regularity of pulses that causes a resonant condition with a frequency that interferes with other device functions or induces error conditions. The circuit shown randomizes to a motor by random gating of a sequence of commands retained in a shift register. Random gating from the shift register positions occurs through the use of a counter driven by an oscillator, independent of other device functions and clocking circuits, in conjunction with an enabling circuit from a random digitized data source that enables or disables counter advance by the oscillator. In the disk drive environment shown, randomizing has no significant effect on the closely regulated speed since the corrective commands occur during each sector of revolution or about thirty-six hundred times per second and motor rotational inertia precludes any meaningful change during a sector rotation.