Patent ID: 7646679

Claim:
A display mechanism for a timepiece, arranged to be driven from a base wheel of a horological movement for controlling movements of a member displaying an indication relating to time or to functioning of said timepiece in connection with graduations indicating values located apart from each other with a predefined movement amplitude of said display member to travel from one to another of said values, said display mechanism comprising a cam having a periphery of predefined shape and driven by said base wheel, said periphery having a continuous main portion, extending between a smallest radius and a largest radius with an irregular radius of curvature, and a transition portion linking said smallest radius to said largest radius, a lever mounted so as to pivot, with reference to a frame element of said horological movement, between first and second extreme positions associated with predefined values of said indication, said lever carrying a sensing finger engaged with said periphery of said cam in order to define an indication position at a given moment, said lever also carrying a rack arranged in engagement with a pinion arranged to drive said display member, at least one elastic organ exerting a force on said lever in order to tend to position it in said indication position, said graduations being designed such that said predefined movement amplitude of said display member to travel between two consecutive values varies along said graduations, according to said irregular radius of curvature of said cam periphery, such that a rotation of said cam by a given rotation angle causes a variable movement of said display member dependent on the angular position of said cam with reference to said frame.