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. 27, 2009
Filed:
Oct. 10, 2005
Ulrich Hahn, Neustadt, DE;
Günter Schwesig, Erlangen, DE;
Ulrich Hahn, Neustadt, DE;
Günter Schwesig, Erlangen, DE;
Siemens Aktiengesellschaft, München, DE;
Abstract
In a method for monitoring a stationary condition of a drive device, a monitoring device provides the drive device with a temporally varying monitoring signal which, when a sensor device connected to the drive device functions properly, modulates a sensor output signal of the sensor device in accordance with the monitoring input signal. The monitoring device receives the sensor signal and monitors it for the presence of a corresponding signal component. In the absence of such a signal component, the monitoring device controls a safety device which converts the drive device into a safe state. When the drive device is controlled by means of at least two phase-shifted current regulators, it is possible for the monitoring device to monitor an output signal of at least one of the current regulators for constancy and to control the safety device when the output signal of the at least one current regulator changes.