Patent ID: 8095311

Claim:
A navigation apparatus for a vehicle, the apparatus comprising: a present position acquisition unit configured to acquire a present position of the vehicle; a storage unit configured to store road data and interchange data, including positional data related to entrance interchanges and exit interchanges of a toll road; a control unit comprising: a travel road designation unit configured to designate, in order, travel roads, on which the vehicle travels, by amending present positions acquired by the present position acquisition unit, based on the stored road data, while considering an allowable error between the acquired present position and the stored road data, an entrance designation unit configured to designate an entrance interchange, by which the vehicle enters the toll road, based on the acquired present position and the stored interchange data, and an exit determination unit configured to determine whether the vehicle approaches an exit interchange, by which the vehicle exits the toll road, after the entrance interchange is designated; and a toll calculation unit configured to calculate a toll from the designated entrance interchange to the approached exit interchange when the vehicle is determined to approach the exit interchange, wherein when the entrance designation unit designates an entrance interchange, the control unit is configured to determine whether a discontinuity has occurred between the travel roads in an order designated by the travel road designation unit, and when it is determined that the discontinuity has occurred, the control unit is further configured to i) designate a travel road, which was designated as such prior to the occurrence of the discontinuity, as a reference travel road used in estimating an entrance interchange actually passed through, instead of designating as the reference travel road, a travel road designated as such posterior to the occurrence of the discontinuity, and ii) re-designate an entrance interchange based on the designated reference travel road, whereas the toll calculation unit is further configured to calculate a toll from the entrance interchange re-designated by the control unit to the approached exit interchange when the vehicle is determined to approach the exit interchange.