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:
Jan. 05, 2010
Filed:
Jan. 18, 2006
Jens Titschert, Lunen, DE;
Markus Lenzing, Selm, DE;
Jeff Travis, Fairmont, WV (US);
Dan Ferguson, McKees Rocks, PA (US);
Jens Titschert, Lunen, DE;
Markus Lenzing, Selm, DE;
Jeff Travis, Fairmont, WV (US);
Dan Ferguson, McKees Rocks, PA (US);
DBT GmbH, Lunen, DE;
Abstract
A protection circuit for intrinsically safe electromagnetic actuators operating on the voltage from a power unit () approved for underground mining, for switching electrohydraulic valves () in underground mining, comprising at least two spaced-apart short-circuit means (orA) connected in parallel with the electromagnetic actuator coil () for short-circuiting the coil in the event of a reversal of the coil voltage. According to the invention, at least one of the short-circuit means comprises a short-circuit semi-conductor switch (orA) and a voltage-reversal detecting circuit () for activating the short-circuit semiconductor switch ().