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:
Apr. 26, 1983
Filed:
Jun. 18, 1981
Applicant:
Inventor:
Robert W Arnold, Glen Aubrey, NY (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01H / ;
U.S. Cl.
CPC ...
361154 ; 361152 ;
Abstract
A constant energy drive circuit for an electromagnetic print hammer has a chopping circuit including a comparator which cycles a switch connecting the energizing coil of the print hammer to an unregulated power supply. Changes in the drive voltage of the unregulated source are compensated for by altering the switching rate of the switch by adjusting the amplitude of a reference signal applied to the comparator. The reference signal adjustment is inverse to changes in the drive voltage.