Abstract: Improvements with the present invention is concerned relate in particular to special bimodal semi-trailers adapted to travel on both rails and roads, wherewith the rail carriage and the highway carriage as well are removable. The invention may be applied if the highway carriage is non-removable. The invention may be applied if the highway carriage is non-removable, or with other types of bimodal semi-trailers.

Abstract: The semi-trailer is capable of traveling on roads or on rails. It is characterized in that both a rail truck and a highway carriage are rapidly removable. Therefore the semi-trailer can travel on roads with only the highway carriage, and on rails with only the rail truck. The advantage is a reduction in the tare of the rail-operable unit. An additional advantage is the lack of a need for all the means intended for maintaining the wheels of the highway carriage elevated above the plane of the rails when traveling on rails, which means are required for all prior art binary rail and road vehicles. Other characteristics of the invention are the coupling device between the semi-trailers, the system of connection of a center pin socket to a hemispherical center-bearing counter-element of the rail truck, and the use of special support props and jacks.