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:
Dec. 21, 1993
Filed:
Mar. 14, 1991
Keith Wright, Preston, GB;
Paul M Fowler, Preston, GB;
Kwok W Chan, Chorley, GB;
John S Tuson, Leyland, GB;
Eaton Corporation, Cleveland, OH (US);
Abstract
Open-circuit and closed-circuit faults in a solenoid controlled actuator are detected using shunt resistors (R1, R4) across the solenoid (1), a transistor switch (4), and a voltage monitor (7) and/or (14) across one or both of these which can detect a faulty open-circuit solenoid that is not energized, or a faulty closed-circuit solenoid that is energized. According to the present invention, before each change in actuator position, the solenoids are all caused to assume an opposite energization condition for a period of time insufficient to move the actuator, but enough to check the voltage monitor responses. In this way, both open and closed circuit faults are detected.