Coupling device for an automotive vehicle

This coupling unit consists of a pair of front links (8) and a pair of rear links (9) pivoting on a frame (6) fixed to the tractor (2). The free ends of the front and rear links (8,9) are connected to a coupling shaft (12) at the rear of which is a coupling hook (13). In order to adjust the position of the coupling hook, the rear of the coupling shaft is connected to hydraulic cylinders (17) whose upper ends pivot on a bearing (20) mounted on a gear box (5).