Driving device for mechanical timepiece movements

A driving device for mechanical timepiece movements, said device comprising a barrel-drum, a barrel-bridge, an arbor coaxial with said drum and pivoting in said bridge, a toothed ratchet-wheel secured to said arbor and disposed adjacent to said bridge, and a one-piece click comprising a rigid portion rotatable about said arbor between a locking position and an unlocking position, a resilient arm, and a beak disposed at a free end of said arm, said beak being adapted for engagement in said toothing of said ratchet-wheel, wherein said bridge comprises a recess in which said click is disposed between said bridge and said ratchet-wheel, and said click further comprises a support element disposed at said free end of said resilient arm and situated within the peripheral limits of said ratchet-wheel, said recess having sides comprising, for determining said locking position, at least a first banking cooperating in said locking position with said support element and a second banking cooperating in said locking position with said beak.