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. 17, 2001
Filed:
Sep. 04, 1998
Kurt Stoll, Esslingen, DE;
Walter Suchy, Stuttgart, DE;
Festo AG & Co., Esslingen, DE;
Abstract
A circuit device for the regulation of the coil current flowing through a solenoid coil arrangement is proposed. It comprises a regulating means having a measuring arrangement for measuring the coil current and adapted to regulate the coil current in a manner dependent on the measured coil amperage, means for producing a attraction current, which regulated by clock pulse switching, flowing through the solenoid coil arrangement and a switching over means for reducing the coil current after elapse of an attraction time to a lower clock pulse switched hold current flowing until the end of a switch signal. The measuring arrangement is switched outside the freewheel circuit in which during the freewheel condition, existing in clock pulse switching intervals, of the solenoid coil arrangement the freewheel current flows. This means that the input voltage does not have to be adapted to the desired attraction current and the freewheel current does not produce any power loss in the measurement arrangement.