Piloting device for piloting a braking valve of a trailer

A piloting device (4) for piloting a braking valve of a trailer, comprising a piloting circuit (45) that can be connected to the braking system of a towing vehicle, a hollow body (40) defining a chamber (41a, 41b) communicating with said piloting circuit (45) and inside which is housed sealed and sliding at least a piloting piston (42, 43) meant to cooperate with the braking valve (3) of a trailer, and a contrasting circuit (47) communicating with the chamber (41a, 41b) on the opposite side of the piloting circuit (45) with respect to the piloting piston (42, 43) in such a way that the piloting circuit (45) and the contrasting circuit (47) apply a first and a second action, respectively, on the piloting piston itself directed towards an opposite direction to one another.