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:
Nov. 18, 1986
Filed:
Sep. 17, 1985
Abstract
In a head position control apparatus, a magnetic pole disc mounted on a DC motor has a plurality of opposite magnetic poles arranged on its circumference in a predetermined relationship with tracks on a floppy disk. A sensor located close to the pole disc generates a pulse signal having pulses corresponding to the tracks and a voltage representing the actual speed of the motor. The pulses are counted in an incremental or a decremental mode. The difference between a track position indicating command signal from a keyboard and the pulse count is detected for deriving a direction signal which indicates the direction of the head and determines the count mode, a speed reference variable according to a predetermined transfer function and a switching signal when the difference reduces below a certain limit. A speed control signal is generated representing the difference between the speed reference and the actual speed of the motor. A position control signal is generated representing the difference between the amplitude of the pulse signal and a reference voltage. In response to the switching signal one of the control signals is applied to a polarity inverter for inverting or noninverting its polarity depending on the direction signal and on its amplitude relative to the reference voltage.