Patent ID: 7522476

Claim:
A calendar mechanism for displaying a date and a day of a week in a timepiece, comprising: a date indicator formed by a crown with an inner toothing; means for driving said date indicator including a first drive wheel having an external toothing so as to be able to be driven about an axis of rotation by a wheel set secured to an hour wheel of said timepiece, said external toothing comprising a prominent tooth and other teeth, said prominent tooth longer than said other teeth and disposed to abut against a tooth of the inner toothing of the date indicator to move it forward one day in a time interval located around a determined time of the day; a day of the week indicator; means for driving said day of the week indicator to move it forward one day during said time interval; means for positioning said indicators wherein said means for driving the day of the week indicator comprises a second drive wheel fitted with an external toothing, superposed and coaxial to the first drive wheel, wherein said first and second drive wheels have respective diameters that are equal and respective even numbers of teeth which are equal, said first and second drive wheels both engaging said wheel set secured to said hour wheel so as to be driven by said wheel set, and wherein said wheel set is formed by a pinion secured to a pipe of said hour wheel and including a number of teeth equal to half of that of said first and second drive wheels.