Patent GB-910082-A (GB)
Title: Improvements relating to mechanism for operating the date part of an automatic calendar
IPC: G04B19/243
Filed: 1959-04-09
Abstract: 910,082. Date indicators. SOLARI & C. UDINE S.p.A. April 9, 1959 [April 9, 1958], No. 12031/59. Class 106 (4). Mechanism for operating the date part of an automatic calendar in response to the twenty-four hourly rotations of a cam 1 comprises an actuator 5 which on downward movement transfers energy to storing means which on release of the actuator 5 serves both to lift the actuator 5 again to release a gear-wheel 17 and to drive the wheel 17 to operate the date part, being stopped after a predetermined movement, the energy storing means also driving a pair of control discs 24, 28 at different speeds, the faster 28 acting or not acting on the slower one 24 at the end of each month in a manner dependent on the number of days in the particular month in a four-year period, and the slower disc 24 then controlling the predetermined movement permitted to the wheel 17 according to the length of the month. The energy storing means comprises three springs 29, 9, 10, of which the first 29 is a torsion spring which is tensioned while the cam 1 is lifting a pivoted arm 4 causing the actuator 5 to bear down on a latch arm 13. At midnight, when the cam 1 releases the arm 4, this spring 29 lifts the latch 13 clear of a stop 14 on a gear-wheel 16 to release the wheel 17 and raises the actuator 5 which turns a lever 6 anticlockwise thereby stressing the helical spring 10 while the spiral spring 9 drives the released wheel 17. While the actuator 5 is descending the helical spring 10 transfers energy to the spiral spring 9 by imparting clockwise rotation to the lever 6 which turns a ratchet wheel 8 through a pawl 7, overwinding being prevented by a pin and slot connection between the lever 6 and actuator 5 providing for lost motion. In each revolution of the wheel 16, the wheel 17 turns a fortieth of a revolution andturns a flap-drum indicator a tenth of a revolution to change the units figure of the date, transfer mechanism to a tens flap-drum indicator being provided. The control disc 24 turns with the wheel 17 and for each revolution thereof the control disc 28 advances a forty-eighth of a turn relative thereto. For <SP>27</SP>/ 40 ths of its circumference the periphery of the disc 24 is raised and through a roller 30 limits the rocking of latch 13 so that another stop 15 on the wheel 16 is engaged before a single revolution is completed. When the roller 30 engages the remainder of the periphery of the disc 24 the latch 13 clears both stops 14, 15 on the wheel 16 which turns freely until the raised part is encountered. The disc 24 carries a pivoted arm 35 whose abutment 31 normally extends the raised periphery of the disc 24 by a further <SP>3</SP>/ 40 ths of its circumference but can be rocked by pegs 33 on the disc 28 to extend the raised periphery by only two, one or no fortieths according to the radial disposition of the pegs 33 which are arranged according to the way 30, 29 and 28 day months are interspaced among 31 day months throughout a period of 48 months. A cam 36 moves with the wheel 17 and is followed by a roller 37 on an arm 38 which advances the month indicator through a pin wheel 41.