Patent ID: 6082268
Filing Date: 2000-07-04
Classification: B61B,B61L

Abstract:
A transportation system, comprising: a plurality of carrier vehicles, a guideway for guiding said carrier vehicles for movement therealong, and track means supported by said guideway and arranged for connection to terminals of an electrical power source, said track means including a pair of metallic electrically conductive left and right lower tracks and a pair of metallic electrically conductive left and right upper tracks, track support means for supporting said tracks from said guideway, each of said carrier vehicles including electrically powered drive means for coaction with said guideway for effecting movement of said carrier vehicle along said guideway, front and rear pairs of left and right lower wheels for engagement with said pair of left and right lower tracks for support of said vehicle, front and rear pairs of left and right upper wheels engageable with said upper tracks to restrict rocking movements of said carrier vehicles, pressure applying means for urging said upper wheels into pressure engagement with said upper tracks, said wheels including metallic peripheral portions for electrically conductive engagement with said tracks, and conduction means for electrically connecting said metallic peripheral portions of said wheels to terminals of said electrically powered drive means of said vehicle, said track support means including insulation means to allow conduction of current between said terminals of said source of electrical power and said terminals of said electrically powered drive means of said vehicle, said current being conducted through said tracks and through said metallic peripheral portions of said wheels and said conduction means, said electrical power source being a source of three phase AC current having first, second and third terminals, said electrically powered drive means including a three phase AC motor having first, second and third terminals, and said track means being so connected to said terminals of said source and said conduction means being so arranged as to allow said conduction of current between said first, second and third terminals of said source and said first, second and third terminals of said AC motor.