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:
Jul. 06, 1982
Filed:
May. 28, 1980
Karl-Heinz Pilz, Baltmannsweiler, DE;
Wolfgang Grater, Stuttgart, DE;
Hans-Dietrich Mayer, Baltmannsweiler, DE;
Richard Hirschmann, Radiotechnisches Werk, Esslingen, DE;
Abstract
A reversible d-c motor, driving a load such as a vehicular radio antenna, has its armature winding connected in a transistorized energizing circuit which is activated by a start circuit and locks operated as long as the motor speed surpasses a certain threshold, i.e. until a major obstacle or a terminal position is encountered. The threshold may be determined by a voltage sensor detecting the counter-e.m.f. induced in the armature winding, by a Hall-effect device in the magnetic field of the stator, or by a speed sensor. The armature winding lies in series with a current limiter which determines the maximum torque applied to the load and may also transmit a no-load signal to a protective circuit when the motor is found idling, the protective circuit including a timer which cuts off the motor after a predetermined idling period. Alternatively, the operating period may be determined by a pulse counter de-energizing the motor after a preferably settable number of rotor revolutions.