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:
Mar. 19, 1991
Filed:
Aug. 17, 1989
NEC Corporation, , JP;
Abstract
An unmanned vehicle guide system has guide routes made of a magnetic material and an unmanned vehicle guided to travel on the guide route. The unmanned vehicle has an exciting coil for emitting a magnetic field, a pair of detection coils, arranged in a direction perpendicular to the travel direction of the unmanned vehicle, for detecting a magnetic field change, a comparator for measuring an output-difference between the detection coils, and a steering device for steering the unmanned vehicle such that the output-difference becomes a predetermined value. At an intersection where a plurality of guide routes intersect and in the vicinity thereof, at least one guide route lacks a magnetic material. Alternatively, an extra marker is added to each of the guide routes that intersect at the intersection.