Patent GB-558981-A (GB)
Title: Improvements in or relating to time recorder
IPC: G07C1/06
Filed: 1941-11-05
Abstract: 558,981. Time printing machines; clocks. INTERNATIONAL BUSINESS MACHINES CORPORATION. Nov. 5, 1941, No. 14292. Convention date, Nov. 5, 1940. [Classes 100 (ii) and 100 (iv)] [Also in Group XVIII] A time recorder comprises a controlling shaft and a controlled shaft both urged to rotate by springs, the controlling shaft being allowed to rotate at a definite rate by an escapement mechanism and having secured thereto a slotted disc, which cooperates with a disc having spaced lugs and geared to the controlled shaft, the lugs passing through the slots at regular intervals so that the controlled shaft is rotated by its spring in uniform steps, and the controlled shaft operating recording means through a releasable connection which permits hand setting of the recording means when desired. Clock hands may also be geared to the recording means for operation therewith. A controlling shaft 22 continuausly driven by a spring drum under control of an escapement carries a flanged disc 26 provided with spaced slots 26a. A second spring drum 18 constantly urges a controlled shaft 25 to rotate in the direction opposite to that of the shaft 22. A gear 29 fast on the shaft 25 drives through gears 30, 31 loose on the shaft 22, a gear 32 loose on the shaft 25 and to which is secured a disk 28 having lugs 27 co-operating with the disc 26 so that when a notch 26a is presented to a lug, the shaft 25 is turned to an entent determined by the distance between the lugs 27. A gear 37 moving with the gear 29 thus turns a shaft 43 carrying the minute hand 41 of a clock and also turns through gears 45, 46, the minute printing wheel of a set of time printing wheels 47. The hour hand 44 of the clock is driven by reducing gear 42 from the shaft 43 and the hour &c. type wheels are driven by usual transfer mechanism from the minute wheel. The gears 29, 37 are connected by a pawl and ratchet device which may be disconnected for hand setting of the type wheels and clock hands. The Specification, as open to inspection under Sect. 91 describes a modification and also platen and ink ribbon mechanisms for co-operating with the time recording wheels 47. The platen arm 58, Fig. 4 (Cancelled), is loosely mounted on the pivot 56 of a bell crank lever 55 so as to be supported normally by that lever to which it is connected by a spring 59. A spring 57 normally holds the bell crank lever 55 against a stop 60 so that its end is beneath a pawl 53 pivoted to a manually operable plunger 51. Upon depression of the plunger against the action of a spring 49, the pawl 53 depresses and then passes the lever 55 so that the latter springs back into contact with the stop 60. The platen however moves further by momentum to make the imprint and then returns to its normal position by the spring 59. The inkribbon is wound on spools 73, 74 and is fed step by step at each operation of the machine by one or other of a pair of pawls 71, 72 pivoted to a plate 70 pivoted on a pin 66 carried by a plate 64 pivoted on the shaft 65 of the type wheels 47. A pin 63 on an estension of the plunger 51 engages a notch in the plate 64 so that as the plunger rises and falls, the plate 64 is oscillated and carries the plate 70 backwards and forwards to cause the operative pawl to feed the ribbon. The plate 70 is held in one or the other of two positions angularly on the pin 60 by the engagement with the upper or lower end of a slot in the plate of a pin 69 carried by a member 67 slidable on a guide pin 68 and provided with end lugs 80,82. When the ribbon is fully unwound from the spool 74, its attachment to that spool prevents movement of the spool 73 when engaged by the pawl 71 on the next operation of the machine with the result that the pin 69 is forced into engagement with the other end of the slot turning the plate 70 so that pins 75, 76 thereon disconnect the retaining detent 77 from the spool 73 and permit the detent 78 to engage the spool 74. At the same time the movement of the member 67 causes the lug 80 to depress the pawl 71 against the action of a spring 81, and causes the lug 82 to move clear of a lug on the pawl 72 to allow that pawl'to be engaged with the spool 74 by a spring 84. In a modified form of time recorder, the minute wheel of the discs 47 is rotated by a pawl on a disc loosely mounted on the shaft of the discs 47 and receiving one oscillation per minute from a lever actuated by a snail cam driven from the shaft of a synchronous motor. This subject-matter does not appear in the Specification as accepted.