A timepiece mechanism includes a first energy source with a regulating member, a second independent energy source, a control member driven by the second energy source, and a blocking device controlled by the first energy source to block the second energy source and release it to allow the control member to be displaced by jumps powered by the second energy source. The blocking device includes first and second mobile parts kinematically interconnected, the first mobile part including a drive device, the second mobile part including a stopping device; a rotating drive member connected to the first energy source and cooperating with the drive device to displace the mobile parts, alternately in opposite directions; and a rotating blocking member connected to the second energy source and cooperating with the stopping device to be blocked by the second mobile part and released at the determined times by second mobile part movement.

A timepiece mechanism includes a first energy source with a regulating member, a second independent energy source, a control member driven by the second energy source, and a blocking device controlled by the first energy source to block the second energy source and release it to allow the control member to be displaced by jumps powered by the second energy source. The blocking device includes first and second mobile parts kinematically interconnected, the first mobile part including a drive device, the second mobile part including a stopping device; a rotating drive member connected to the first energy source and cooperating with the drive device to displace the mobile parts, alternately in opposite directions; and a rotating blocking member connected to the second energy source and cooperating with the stopping device to be blocked by the second mobile part and released at the determined times by second mobile part movement.

Disclosed is a timepiece blocking device including first and second mobile parts kinematically connected to one another, the first mobile part including a drive device, the second mobile part including a stopping device; a rotating drive member turning in a single direction and cooperating with the drive device to displace the first mobile part, and thus the second mobile part, alternately in opposite directions; and a rotating blocking member tensioned and cooperating with the stopping device to be blocked by the second mobile part and released at determined times by the displacements of the second mobile part. Cooperation between the rotating blocking member and stopping device immobilizes the mobile parts when the rotating drive member does not cooperate with the drive device. In normal operation, the rotating drive member contacts the first mobile part only when cooperating with the drive device, i.e. over less than 60% of one revolution of the rotating drive member.