Device for adjusting the usable length of a bracelet and corresponding bracelet clasp

A device for adjusting the usable length of a bracelet comprising first and second free ends, the adjusting device having a frame carrying

• an adjusting element intended to be fastened to the first free end of the bracelet and capable of sliding in the longitudinal direction of the bracelet with reference to said frame,
• an element for fastening the bracelet, at least indirectly mechanically connected to said frame and intended to be fastened to the second free end of the bracelet,
• said adjusting element carrying a toothed rack as well as rungs, both being oriented in the longitudinal direction of the bracelet,
• a jaw which can move between inactive and active positions, in response to a predefined action by a user on a control element, said jaw being designed so as to cooperate with said toothed rack, to define a plurality of distinct adjustment positions in the longitudinal direction of the bracelet, and
• lock said adjusting element in said active position, and
• leave it free in said inactive position, so as to allow said adjusting element to slide from one to another of said adjustment positions, two adjacent distinct adjustment positions defining an adjustment increment for the usable length of the bracelet,
• wherein said control element bears both a knife, intended to cooperate with said jaw to move it into its inactive position, and a projection, intended to cooperate with said rungs, said projection being positioned such that a stop surface faces said rungs as said jaw is in its inactive position and such that said adjusting element is enabled to slide by one adjustment increment only for each of said predefined action by the user on said control element, to allow the usable length of the bracelet to be adjusted.