Patent ID: 8146509

Claim:
A tramway transit system, comprising: a pre-established track; and a vehicle for traveling along the pre-established track, wherein the vehicle includes steering mechanisms each having an electrically driven oil hydraulic actuator for steering front wheels and rear wheels of the vehicle automatically, the track includes a protection track laid down on the track, the vehicle further includes a guard wheel assembly provided at front and rear parts respectively under the vehicle, the guard wheel assembly having a pair of guard wheels which protrude into a groove of the protection track without contacting side walls thereof, and interlocking mechanisms so that a center line connecting centers of the each pair of the guard wheels is directed by the steering mechanisms in the same direction of the front wheels or rear wheels during traveling of the vehicle, wherein said electrically driven oil hydraulic actuator comprises a hydraulic cylinder having a cylinder rod connected via a movable rod to at least one of right and left wheels of the vehicle, a two-way discharge pump for supplying working oil to both actuating rooms of the hydraulic cylinder, a variable speed, reversible rotation motor for driving the two-way discharge pump, and a closed hydraulic circuit including the two-way pump and the hydraulic cylinder and having relief valves for releasing the working oil to an oil storage tank when pressure in the hydraulic circuit exceeds a prescribed permissible pressure, wherein said system further comprises (i) protection arms each having forward and rearward ends extending forward and rearward of the vehicle, respectively, and (ii) steering arms each of which has an end part connected to an end part of the corresponding protection arm via a connecting rod, thereby the guard wheels are moveable without contacting the side walls of the groove of the protection track, said pair of guard wheels provided at the front part and the rear part respectively under the vehicle is constructed so that the guard wheel of the vehicle are respectively connected to the forward and rearward ends of the protection arm, and said protection arms are respectively provided to a front bogie of the front part of the vehicle and a rear bogie of the rear part of the vehicle such that each said protection arm is supported at a center part thereof rotatably in a width direction of the protection track by the front bogie and the rear bogie respectively.