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:
Jun. 19, 1979
Filed:
Aug. 02, 1977
Bert Cappel, Lammerspiel, DE;
Alfred Dorn, Lammerspiel, DE;
Abstract
A control system for a reversible screwing tool for tightening and loosening screws in a printing press or the like which includes a pair of angularly spaced pick-up devices coupled to the shaft of the tool for generating respective series of impulses. Monostable pulse generators are coupled to the respective pick-up devices, the generator coupled to the pick-up device in leading position, for counterclockwise rotation, being set to produce an output pulse which is substantially wider than that produced by the generator which is connected to the pick-up device in trailing position so that during counterclockwise rotation the output pulses from the generators timingly overlap one another. The generators feed into the input terminals of an AND gate which is, in turn, connected to a counter which counts the pulses resulting from counterclockwise rotation of the shaft. A relay interposed between the source and the tool automatically turns off the tool when a predetermined count is achieved thereby insuring that the screw is not excessively unscrewed from its tight condition. The relay is resettable in readiness for engagement of the succeeding screw. In the preferred embodiment of the invention the generator which is coupled to the pick-up device in leading position is responsive to the trailing edge of the received impulse while the generator connected to the pick-up device in trailing position is responsive to the leading edge of the pulse which it receives.