Method for perpetual display of week number in year for watch movement, involves mechanically displacing mobile display unit on night of Sunday to Monday by two steps when Sunday carries specific date if unit displays week number fifty two

摘要

The method involves displacing a mobile display unit e.g. disk or hand, with respect to an aperture or a graduation in a stepwise manner at a rate of one step per week on night of Sunday to Monday for displaying week number from one to fifty two or fifty three. The display unit is mechanically displaced on the night of Sunday to Monday by two steps instead of one step, when the Sunday carries date 28, 29, 30 or 31 in December or date 1 or 2 in January if the display unit displays the week number 52. Independent claims are also included for the following: (1) a mechanism for perpetual display of week number, for a movement of a timepiece (2) a timepiece comprising a movement provided with a date mechanism.