GB522781A - An improved date-indicator for time-pieces - Google Patents

Abstract

522,781. Date indicators. HARRISON, T. H. Nov. 18, 1938, No. 33546. [Class 106 (iv)] A date indicator comprises two rotatably mounted members 1, 2 bearing date numerals and the names of the months respectively, a date feed lever 16 movable by means, e.g., the clockwork mechanism of a timepiece, adapted to impart an intermittent rotary feeding movement once in every twenty-four hours to the rotatable date member 1, said date lever 16 having two fixed arms 20, 21 adapted to co-operate with a pair of surplus feed cam tracks 9, 29 (one track 29 moving with the rotatable month member 2 and the other track 9 stationary), a month feed member 33 movable by means associated with the rotatable date member 1 and adapted to impart intermittent rotary movement to the rotatable month member 2, and an element 43 on the date member 1 adapted on the last day of a twenty-eight day month and of a thirty-day month to engage with one arm 20 of the date lever 16 to advance the date member 1 through an angular surplus feed movement corresponding to three days and one day respectively. The hour hand pipe 4 of a clock carries a pinion 14 which drives a gear 15 a pin 19 on which oscillates trident lever 16 once each day, an arm 25 of this lever bearing a claw 26 which engages teeth 27 to advance a member 3 bearing the names of the days of the week. The two outer arms 20, 21 carry claws 22, 23 to engage with a row of thirty-one teeth on the inner periphery of dial 1. A fixed circular wall 9 having a gap 28 separates dials 1 and 2 while the month dial 2 has a flange 29 with four gaps 30 corresponding to the thirty-day months and a longer gap 31 corresponding to February. Normally claw 22 which is wide is kept clear of the teeth 24 of dial 1 by engagement with flange 29, and claw 21 moves dial 1 one step after coming to the gap 28 in wall 9. At the end of February, long gap 31 on flange 29 is so placed that claw 22 drops down immediately behind a high tooth 43 and moves dial 1 a distance of 2¢ divisions before riding over the crest of wall 9. Claw 23 completes the movement by advancing dial 1 one-and-a-half divisions. For the thirty-day months, shorter gaps 30 are so disposed that claw 22 moves dial 1 half a division and claw 23 the remaining one-and-a-half divisions. For the other months no gaps are provided in flange 29 and claw 22 does not engage tooth 43. At the end of each month, pin 32 on dial 1 contacts the toe portion of month lever 33 which has a claw 34 which by engaging one of twelve teeth 35 moves forward month dial 2 one step. Small rubber rollers 39, Fig. 9, are used for adjustment of the dials in leap years, springs 42 preventing backward rotation and holding the rollers 39 against their apertures to keep dust out of the case.