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:
May. 06, 1980
Filed:
Aug. 31, 1978
Jeffrey L Lovgren, Rochester, MN (US);
William P Quinlan, Rochester, MN (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A control system for applying a magnetic head onto a magnetic disk in random places thereon including a free running oscillator and switching means responsive to pulses from said oscillator and a head load command signal derived from the disk during a revolution thereof for initiating the energization of a head engaging solenoid. The system includes a capacitor which is charged at various rates to produce an initial fast rising current in the solenoid for moving the head into close proximity with the disk, a slowly rising subsequent current in the solenoid for engaging the head with the disk gradually, and a final fast rising current in the solenoid for completing the engagement of the head on the disk.