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:
May. 02, 1989
Filed:
Sep. 17, 1987
Koji Ochi, Iwamizawa, JP;
Masahide Harada, Sapporo, JP;
Nippon Oil and Fats Co., Ltd., both of, JP;
Harada Electronics Industry, both of, JP;
Abstract
A delay type electric detonating primer for use in a multiple-step blasting system including a capacitor for storing electric changes supplied from an electric blaster via bus wires and leg wires, an actuation circuit connected across the capacitor for generating an actuation signal when an energy supply from the electric blaster is stopped, a clock pulse generating circuit having a crystal oscillator and being energized with energy stored in the capacitor to produce clock pulses, a counting circuit which is initiated to count the clock pulses in response to the actuation signal, and generates an ignition signal when the counter has counted the predetermined number of clock pulses, and a switching circuit for discharging electric charges stored in the capacitor through an igniting resistor in response to the ignition signal.