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. 28, 1976
Filed:
Aug. 07, 1974
Eugene Dale Johnston, Roseville, MN (US);
Sydney J Roth, Edina, MN (US);
Joseph A Marino, Waukesha, WI (US);
Applied Power Inc., Milwaukee, WI (US);
Abstract
Engine diagnostic apparatus for displaying on a cathode ray tube the voltage conditions existing at each of the spark plugs which apparatus is intended for use with ignition systems in which the voltage pulses applied to the spark plugs are of such short duration that a cathode ray tube will not properly respond to the changes of voltage. The apparatus is effective to successively charge a capacitor to a value corresponding to the value of each voltage pulse and the voltages across this capacitor are used to control the vertical defection of the cathode ray tube. At the end of a first period of time following a voltage pulse, the capacitor is shorted. The capacitor is maintained shorted for a longer period of time less than the time between successive pulses so as to avoid undesired charging of the capacitor as a result of transient conditions. The time constant of the charging circuit for the capacitor is less than the duration of the voltage peak so that the capacitor is substantially fully charged during the voltage peak.