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:
Jan. 16, 1990
Filed:
Oct. 12, 1988
Koji Ochi, Iwamizawa, JP;
Masahide Harada, Sapporo, JP;
Nippon Oil & Fats Co., Ltd., , JP;
Harada Electronics Industry, , JP;
Abstract
An electric detonator of delay type including leg wires connectable to bus wires, a capacitor connected across the leg wires for storing the electric energy supplied from an electric blaster via the leg wires, a delay circuit connected across the leg wires and generating an igniting signal at a predetermined timing, a switching circuit and an igniting resistor connected to the switching circuit, whereby the switching circuit is made conductive in response to the igniting signal to discharge the electric energy stored in the capacitor through the igniting resistor to explode the detonator. In order to operate the detonator reliably and safely, there are provided low and high voltage protection circuits for discharging the electric energy therethrough when the power supply voltage is out of a predetermined normal operation range.