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:
Nov. 15, 1994
Filed:
Mar. 15, 1993
Asahi Kasei Kogyo Kabushiki Kaisha, Osaka, JP;
Abstract
An electronic delay circuit for firing an ignition element. The delay circuit includes a capacitor which stores electric energy supplied from an electric blasting machine, an oscillator generating a clock pulse train, a circuit for over-exciting the oscillator, a counter which counts clock pulses of the clock pulse train, and a circuit for maintaining a reset state of the counter for a predetermined time period after the electric energy is supplied. The counter produces a trigger signal when it counts a predetermined number of the clock pulses, and the electric energy stored in the capacitor is discharged to the ignition element. Since the oscillator enters into the steady state in a very short time by the over-excitation, the delay circuit has large resistance to external noise.