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. 09, 1978
Filed:
Feb. 25, 1977
Applicant:
Inventor:
Robert H Schmidt, Minnetonka, MN (US);
Assignee:
Electro-Craft Corporation, Hopkins, MN (US);
Primary Examiner:
Int. Cl.
CPC ...
H02P / ;
U.S. Cl.
CPC ...
322 90 ; 307304 ; 318138 ; 322 94 ; 324163 ;
Abstract
A brushless tachometer utilizing four stator windings and series connected field effect transistor commutation switches to provide an input to a summing amplifier. Connection of the field effect transistor switches to the summing junction of the amplifier and use of series resistance and back-to-back clamping diodes on the winding side of the field effect transistors permits commutation switching with a minimum of transient voltage changes due to interruption of the stator winding current.