Patent GB-516795-A (GB)
Title: Improvements in or relating to printing calculating or the like machines
IPC: G06C11/04
Filed: 1938-07-08
Abstract: 516,795. Calculating-apparatus. BURROUGHS ADDING MACHINE CO. July 8, 1938, No. 20260. Convention date, July 9, 1937. [Class 106 (i)]  In a printing calculating machine having type carriers with cipher and special character type controlled by the differential actuating mechanism, the members connecting the type carriers with the actuator racks are connected with the racks in a manner which permits the connecting members and type carriers to move one step from their normal position before the racks are entrained. A means controlled by the movements of the connecting members causes a special character to be printed in all orders higher than the highest significant denomination and a zero to be printed in all lower orders in which no significant digit is to be printed. The invention is shown applied to a machine of the Burroughs type as described in Specification 105,928, [Class 106 (i)]. The actuator racks 4, 5, Fig.. 1, for the line totalizer 6 and lower totalizer 7 are mounted for limited movement .on the differential stop bars 3 to which are pivoted sectors 8 carrying type 11. The impression mechanism comprises spring controlled hammers 12 with latches 13 and control pawls 14. Each pawl 14, except that for the third lowest order, is provided with a tail 16 .that engages the sector of corresponding order in such manner that when a sector is raised above zero position the pawl 14 is rocked to engage its'latch- 13 so as to release the hammer 12 at the end of the forward stroke. The latches 13 of all but the lowest order have lateral projections 91, Fig. 2, each of which lies in front of a projection on the latch of next lower order so that a latch releases all those of the lower orders. The type carriers for the three lowest orders have type from "9" to "0" the remainder, except the highest order, have in addition an asterisk "<SP>*</SP>" and the highest order has a dollar sign "$" instead of an asterisk. In normal position the "0" type is one line below the printing position. Each stop bar 3 is provided with a stud 20 overlying a spring controlled pawl 21 pivoted to a bracket 23 that is secured to a plate 27 supported on shafts 28 slidably mounted in brackets 29. Secured to the rear end of the shafts 28 is a cross bar 31 to which is pivoted a link 32 with an upstanding foot 34 at its rear end in position to engage a stud 35 on an arm 36 secured to the main driving shaft 37. The link 32 also has an arm 38 with a stud 39 engaging a cam 40 journalled on a shaft 41 but yieldingly connected thereto by a spring 42 and arm 43. In operation when the stop bars 3 move forwardly to their differential positions those arrested in the " 0 " position will have their studs 20 in front of shoulder pieces 47 on their pawls 21 as in Fig. 4, while those bars that move to digital positions will move the stud 20 to a position as shown in Fig. 5. The pawls 21 are normally held in lowered position by a cross bar 26. During the operation the link 32 moves rearwardly and the pawls 21 are rocked or blocked depending on the position of the studs 20. The pawls of the five highest orders have each a projection 51 overlying a projection 50 on the pawl of next lower order so that when a pawl is blocked all lower orders will be held against movement. During the continued rearward movement of the link the shoulder pieces of those orders to the left of the highest significant figure will engage the studs 20 and will return the corresponding stop bars to normal position so as to place the special character or asterisk type at the printing line. To effect the printing the corresponding hammers must be released. A link 81, Fig. 2, is connected at its forward end to a bell-crank 82 that is provided with a horizontal extension 86 engaging a pawl 87 pivoted to the hammer latch 13 of the third lowest order which is operated ,in every cycle. The pawl 87 is provided with an extension 89 ,engaging the shoulder of a pawl 90 pivoted to the latch 13 of the highest order so that when this latch is released all other latches will be released through their projections 91. This mechanism' is under the control of the paper carriage to effect printing of amounts, without the special characters by the provision of rollers 75. Fig. 1, co-operating with a bellcrank 76 operatively connected by a link 78 to the link 81 so as to move it forwardly to raise the pawl 87 and disengage extension 89 from the pawl 90. If the machine is used for cheque writing, printing in certain orders must be suppressed in certain columnar positions. For this purpose rollers 108 on the carriage operate a linkage 106, 104 to displace a rack 103 in mesh with a pinion 102 which sets a shaft 100 with respect to fingers 101 projecting forwardly from the type hammers. '