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:
Apr. 29, 2003
Filed:
Dec. 07, 2000
Michihiro Kaneko, Tsurugashima, JP;
Koichi Nagaki, Tsurugashima, JP;
Pioneer Corporation, Tokyo-to, JP;
Abstract
A navigation system detects a present position of a movable body and performs a navigation for the movable body on the basis of map information. The navigation system is provided with: a storage device ( ) of non-volatile type capable of writing the map data thereinto and reading the map data therefrom; a map data transferring device ( ) for obtaining the map data corresponding to a predetermined area, and transferring and storing the map data corresponding to the predetermined area to the storage device; an empty area judging device ( ) for judging whether or not an empty storage area having a predetermined capacity is reserved in the storage device when the map data transferring device is to transfer the map data corresponding to the predetermined area to the storage device; and an erasing device ( ) for determining unnecessary data among data stored in the storage device on the basis of a predetermined condition, and erasing the unnecessary data from the storage device if the empty area judging device judges that the empty storage area is not reserved.