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:
Jun. 01, 1976
Filed:
Sep. 03, 1974
David P Erdmann, Hopkins, MN (US);
Dennis L Kurschner, Minnetonka, MN (US);
Honeywell Inc., Minneapolis, MN (US);
Abstract
A system for sensing seismic and magnetic disturbances, comprising a segmented transducer, such as a line sensor, and electronic circuitry for processing the signals developed by the segmented transducer. The segmented transducer comprises sets of windings wrapped around a ferromagnetic core. Currents are induced in the transducer windings by magnetic field disturbances caused by external ferrous objects. Electronic signal processing circuitry associated with the transducer extracts information from the induced seismic and magnetic signals and activates an alarm if the information meets predetermined criteria. Important criteria used include whether the seismic signals are impulsive, whether the magnetic or stress disturbances are localized, and whether specific thresholds of magnetic and stress activity are reached.