A clockwise torque is applied by weight 6 to disk 5 which rotates about fixed axis A. Pawl 2 is keyed with planet pinion 3 to a stud shaft. Pinion 3 meshes with fixed sun gear 4, forming planetary gearing of which disk 5 is the carrier. Link 1 rotates about axis A and has braking surface a on one half of its hub circumference. One end of spiral spring 7 is attached to disk 5 and the other to link 1. Spring 7 turns link 1 so that pawl 2 slides off braking surface a, allowing disk 5 to rotate. Pinion 3 rolls around gear 4 until pawl 2 again contacts the braking surface and stops rotation. At the same time, spring 7 is wound up because link 1 is stopped beforehand by a device that is not shown.
$2740$RG,ML$