Annual calendar mechanism for a timepiece
AssigneeCompagnie des Montres Longines, Francillon S.A.
InventorFrank Vaucher
Life of this patent
Estimating the term…
Abstract
A timepiece such as a watch carries a date ring with a window display. The ring carries an engaging system capable of driving at the end of each month an annual ring having twelve or twenty four external teeth and five internal teeth. A calendar driving wheel set has a first finger capable of driving the date ring and a second finger capable of driving the annual ring. At the end of a month of thirty days, one of the five internal teeth of the annual ring appears on the path of the second finger and drives this ring in its travel, such ring, from being driven becomes a driving wheel and, via the engaging system, causes the date ring to advance to the first of the following month. A manual correction remains necessary at the end of the month of February.
Claims11
An annual calendar mechanism for a timepiece, said mechanism comprising a date ring fitted with thirty one internal teeth inside the ring, onto which are applied thirty one numbers each corresponding to a day of the month which are displayed successively through a window made in a dial, and a calendar driving wheel set making one rotation in twenty four hours, said wheel set having a first finger capable of driving said date ring through one step once a day via one of its internal teeth for changing the displayed number, wherein said mechanism further comprises an annual ring partially superposed on said date ring, said annual ring making one rotation in a year and having external teeth in positions corresponding to the twelve months of the year and five internal teeth in positions corresponding to the months of less than thirty one days, said annual ring being arranged off-centre with regard to said date ring and next to said calendar driving wheel set so that it is actuated, at the end of months of less than thirty one days, by a second finger of said calendar driving wheel set, said second finger acting on one of said five internal teeth of the annual ring, said date ring having engaging means for engaging at least one of said external teeth of said annual ring at the end of each month.
Dependencies are inferred from the claim text.