Tilt trailer in particular for a road transport vehicle carrier

In a trailer adapted to be connected with a front end thereof to a rear-end of a carrier vehicle, said front end of the trailer being held in an operative position of said trailer at a predetermined height above ground, when said trailer is connected to the rear-end of said carrier vehicle, the trailer including a frame defining a trailer frame plane extending in a hauling position of the trailer substantially parallel to the ground, a front extension and a rear extension of said trailer frame extending substantially along said trailer frame plane, said front extension being connected between said front end and the trailer frame, said trailer front end including an elongated drawbar defining a drawbar plane subtending a first angle close to 180.degree. with said trailer frame plane in said hauling position, the improvement comprising

• angle varying means for changing said first angle to a second angle when said trailer frame is in a position for providing access to vehicles to be loaded onto the trailer for subsequent passage to said carrier vehicle, said predetermined height being similar in said hauling and vehicle access positions of said trailer frame, whereby said rear extension touches the ground when said drawbar plane subtends said second angle with said trailer frame plane, so as to provide a gently sloping vehicle access ramp,
• wherein said angle varying means comprises a cylinder-piston unit, and articulated leverage means being connected near one end thereof to a piston rod of said cylinder-piston unit, having another end thereof articulatably connected to said trailer front extension, and having an intermediate hinge thereof connected to said drawbar,
• wherein said articulated leverage means is movable between a hauling state and a vehicle access state, and further comprises self-locking means for preventing movement of said leverage means out of said hauling state along at least one direction when said trailer frame is in said hauling position, and
• wherein said articulated leverage means comprises a first arm hingeably connected with one end thereof to an end of said piston rod, and hingeably connected with another end thereof to said drawbar, and an elbow-shaped arm hingeably connected with one end portion thereof to said other end of said first arm, the other end portion of said elbow-shaped arm constituting said other end of said leverage means.