PERPETUAL CALENDER COMPRISING A QUADRENNIAL CYCLE INDICATOR

摘要

The perpetual calendar mechanism of the invention comprises in addition to the months indicator a four year cycle indicator which displays successively the normal years and the leap-year. The four year cycle indicator is controlled directly or indirectly by a rotatable assembly journalled on the month star such assembly including a year cam and a Maltese cross enabling it to effect one revolution every four years. In one variant illustrated the mechanism includes a first ring bearing the year indications and a second ring concentric to the first ring bearing an index marker. At each year change the index marker is shifted a quarter turn relative to the indications borne by the first ring.