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. 23, 1989
Filed:
Apr. 18, 1988
Eldon Nerheim, Edina, MN (US);
Leonard D Hones, Eden Prairie, MN (US);
Patricia A Douma, Coon Rapids, MN (US);
Earl W McDonald, Eden Prairie, MN (US);
Honeywell Inc., Minneapolis, MN (US);
Abstract
An explosive detonator consisting of an integrated circuit chip having a silicon substrate on which is formed an amorphous or polysilicon bridge, the bridge extending between two metal wire-bonding pads also on the substrate. The integrated circuit chip is disposed in close proximity to a primary charge such that when the bridge is energized by an electric current, it heats to the point where the charge is ignited. By back-etching the silicon substrate under the bridge, parasitic heat conduction is avoided. Further, by bonding a pyrex tube to the chip with the tube's bore surrounding the bridge, it is possible to pack the bore with an explosive train in fabricating the detonator assembly.