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. 24, 1976
Filed:
Oct. 11, 1974
Tex Monroe Dudley, Palo Alto, CA (US);
Electroglas, Inc., Santa Clara, CA (US);
Abstract
A positioning apparatus includes a platen and a head independently movable relative to the platen. First and second coils having a particular phase relationship are disposed relative to each other on the head are independently energized to produce first and second electromagnetic forces. These electromagnetic forces have varying characteristics for moving the head relative to the platen and constant characteristics for maintaining the head in a substantially fixed relationship to the platen. Abrupt changes from the variable to the constant characteristics of the applied electromotive forces allow inertial forces to impart a decaying oscillation of the head about the positional origin determined by the constant characteristics of the applied electromotive force. Oscillation of the head relative to the platen produces first and second back-electromotive force sinusoids in the first and second coils, respectively. Means is provided for detecting the first back-electromotive force sinusoid to produce a damping signal with characteristics similar to the characteristics of the second back-electromotive force sinusoid. This damping signal can be introduced to the second coil to damp the second back-electromotive force sinusoid and inhibit the oscillations of the head.