Patent GB-851188-A (GB)
Abstract: 851,188. Workmen's time-recorders. INTERNATIONAL BUSINESS MACHINES CORPORATION. Nov. 29, 1957 [Nov. 30, 1956], No. 37323/57. Class 106 (4). [Also in Group XXIV] Apparatus for recording elapsed time comprising programme means adapted to control the establishment of a connection between advancing mechanism and elapsed time mechanism to drive the latter at a fixed rate, includes rapid advance means including a spring releasable under the control of the programme means to advance the elapsed time mechanism by a selected amount at a higher rate than the fixed rate. The invention may be applied to the workmen's time-recorder described in the Specification 772,853 and is described as a modification to the elapsed-time programming and drive thereof whereby, over a certain period, workers in consecutive shifts can register their actual times " in " and " out " while at the same time the coded perforations punched in their cards for controlling the calculations of elapsed time conform to the allowable pay period so that, in calculating wages from elapsed time for a shift changing at say 5 p.m. those registering " on " early are only paid as from 5 p.m. and those registering " off " late are only paid up to 5 p.m. Elapsed-time programming. Non-working periods are eliminated from the counting of elapsed time by sensing a programme channel 344, Fig. 5, prepunched at various time indicating positions with a single hole for effecting a " start " signal and two consecutive holes for effecting a " stop " signal. The signal takes the form of a movement of an arm 729, Fig. 7, to the right for a " start " and to the left for a " stop " under the action of levers controlled by successive sensing pins 719, 720, 721. Once a minute a bail 725 is lifted and allows the pins to feel for holes in the tape T, ensuing interactions causing the arm 729 to move to the right when each pin successively 719, 720, 721 feels a single hole and to be restored from right to left when each pair of pins 719, 210 and 720, 721 successively feels a pair of holes. Rapid advance occurs when a prepunched hole in another channel 344 is sensed. Once a minute the bail 725 allows a pin 761, Fig. 8, to feel for a hole in this channel and when one is encountered an arm 774 is moved to the left, being restored later upon the down stroke of the bail 725. Should the tape T break a normal start signal is inhibited through the feeler 721, Fig. 7, and a signal for rapid advance is prevented through an extra feeler 762, Fig. 8. Elapsed-time shaft drive. For normal advance once a minute, the arm 729, Fig. 7, is positioned to the right causing an arm 788, Fig. 15, to be held clear of a lever 784 and once a minute an arm 80, when moving to start the drive motor, also clears the lever 784 allowing it to rock counterclockwise driving bell crank 794 to unlatch a clutch (see Group XXIV) so that rotation of the minute shaft 78 is transmitted to the elapsed-time shaft 797. For rapid advance the movement of the arm 774, Fig. 8, to the left causes an arm 866, Fig. 15, to free a detent 868, so that a clock spring 855 can drive gear 848 until its ear 856 engages the edge 857 on the dial gear 847, the amount of rotation being determined by the presetting of the dial gear 847 in the clamp 849, the gear 848 driving a gear 859, ratchet 860 and cam 861, allowed by the freeing of the detent 868. Thus the cam 861 frees a trip lever 869, Fig. 16, to turn counterclockwise and through arm 870 to turn counterclockwise the bell crank 794 with its latch portion 804. The elapsed-time shaft 797 is thus clutched into the minute shaft 78 and in each half revolution ear 871 or 872 of plate 798 strikes and cams an arm 873 counterclockwise for a pawl 875 to advance the ratchet 860 a tooth to be held by detent 868. Alternately ears 805, 878 try to restore the bell crank 794 but with the trip lever 869 on the low of the cam this is prevented during the few seconds it takes to advance the number of minutes e.g. 15, preset by the dial gear 847. The simultaneous driving of the ratchet 860 by a corresponding number of teeth brings the high of the cam 861 back to relatch the trip lever 869, allowing the return of the bell crank 794 and declutching of the elapsed-time shaft. The drive motor is held active throughout the rapid advance by arranging for contacts 886 to be held closed. The pawl 875 is ineffective during normal advance because an appropriate section of the ratchet 860 is relieved of teeth. Elapsed-time wheels drive. The shaft 797, Fig. 10, drives the hundredths of an hour type wheel 810 through a chain of gears including a pair of mutilated gears for decimal coding and the wheel 810 drives other denominational wheels through geneva transfer mechanism. An aligner 809 is withdrawn during the drive by a cam on the shaft 797 and also during computation by a cam on the computation shaft 106. Another cam on the shaft 106 withdraws slides carrying parts of the drive and transfer chains during a subtraction cycle to enable the type wheels to be backed up.