Wheel collapsible frame

Claim 1

A collapsible frame for a wheeled vehicle, comprising a main tubular structure, a pair of forks which at one end thereof are pivoted to the rear lower side of said tubular structure and each carrying at the other end thereof at least one wheel, a rigid footboard pivoted to the front lower side of the tubular structure and on which at least one rod is mounted, at the running conditions for the vehicle said rod being rotatable about a substantially vertical axis and carrying at an end thereof one vehicle wheel, said rod being provided with means operable to control the rotation thereof about said substantially vertical axis, the frame also comprising a secondary tubular structure pivoted to the upper side of said main tubular structure and forming the rigid portion of a seat, said pair of forks and said footboard, along with tHe wheels carried thereby, being rotatable on respective pins restraining them to the main tubular structure between a closed position, at which they are collapsed within the main tubular structure, and an open position, at which they project from said tubular structure with the wheels supporting the vehicle at running conditions, said secondary tubular structure being rotatable on its pins between a closed position, at which it is overturned on the main tubular structure, and an open position, at which it extends at the rear of the main tubular structure, means being provided for clamping at least said pair of forks and said footboard at said open position, each fork of said pair of forks being connected to said main tubular structure by first and second levers pivoted to one another at an end thereof and with the other end of the first lever pivoted to the fork and the other end of the second lever pivoted to the main tubular structure, said footboard is pivoted to said main tubular structure by at least one first lever and one second lever pivoted to each other at an end thereof and with the other end said first lever pivoted to said footboard and the other end of said second lever pivoted to said main tubular structure, said second lever of each fork and said second lever of the footboard being connected to said secondary tubular structure by motiontransmitting means pivotally connecting on the main tubular structure said secondary tubular structure to the footboard and the pair of forks and controlling the setting at closed position and open position, respectively, for the footboard and the pair of forks upon setting at a closed position and open position, respectively, for the secondary tubular structure on said main tubular structure.