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:
Mar. 19, 1996
Filed:
Aug. 29, 1994
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
While the electric power source is turned on, capacitor 1 is charged to a voltage EO by a direct current constant voltage supplier through transistor 4. When the electric power is disconnected, transistor 4 is switched off to discharge capacitor 1 through resistor R1. When the power source is turned on, the voltage of capacitor 1 is read by A/D converter to be produced and stored in CPU 12 memory. Then transistor 4 is switched on to charge capacitor 1 to the voltage EO. Then transistor 4 is switched off and transistor 5 is switched on to discharge capacitor 1 through resistor R2 and a counter stars. When the voltage of capacitor 1 reduces to the same voltage stored in the memory, transistor 5 is switched off to stop the counter and to obtain the counted value t2. Then transistor 4 is switched on to prepare for the next operation. The time lapse t1 after the power source being turned off is obtained by a formula (R1/R2).times.t2.