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. 24, 1978
Filed:
Jan. 02, 1975
William J Barrett, Rockford, IL (US);
Elwood J Meyers, Rockford, IL (US);
Barber-Colman Company, Rockford, IL (US);
Abstract
An automatic control system wherein repetitive pulses, the frequency of which is responsive to a remote condition such as prime mover RPM, are converted to a D.C. voltage level which is then compared to a reference to produce an error signal. Three further signals are then produced, one proportional to the error signal, one proportional to its integral and the other proportional to its derivative. The three further signals are summed and amplified to the extent necessary and the resultant used to control an element which in turn controls the remote condition. Included is a fail safe circuit effective to cause the remote condition controlling element to shut off in the event incoming pulses are not present. Provision is made whereby the system may respond to the summed signals described above or an external signal which may be derived from a function generator or a limiting value established by an external condition. A particular application described for the system is its use as a governor system for prime movers such as internal combustion engines and steam turbines.