Patent GB-191204376-A (GB)
Title: Improvements in and relating to Calculating Machines.
IPC: G06C7/08
Filed: 1911-04-19
Granted: 1912-06-19
Abstract: 4376. Marks, E. C. R., [McCaskey Electric Calculator Co.]. April 19, 1911. Adding and subtracting apparatus.-Relates to the single-bank keyboard, denominationselecting, and differential setting mechanisms of motor-operated adding-machines, of which the error-correcting and main-operating mechanisms are described in Specification 5651/12 and the totalizer actuating and engaging mechanism in Specification 4680/12. Associated with the nine numeral keys are five denomination.- selecting keys, by means of which, as well as by successive depression of numeral keys, a stop cylinder having rows of movable stops may be rotated by steps up to five at one movement. A row of stops is thus selected, and the numeral key depressed determines the stop in the row which shall become operative. The main slides subsequently move according to the stops thus selected. Keyboards and keyboard interlocks. - The numeral keys 9 and denomination keys 10, Fig. 1, pass through slots in a bar 6, and have projections 22 in line, adapted to enter between rollers 23 contained in a groove so as to prevent depression of more than one key at a time. Each key also depresses the horizontal arm of a rightangled lever 16, and thereby moves the appropriate rod between the keyboard and the differential denomination - selector upon a spindle 42. Simultaneously, a plate 24 below the key-stem draws a yoke 32 over the upper end of the lever and locks the key in depressed position, wherein it remains until the stop cylinder has completed its escapement movement. Differential mechanism.-The stop cylinder is made up of alternate disks 47, 48, Fig. 13, of different diameters, and in the nine annular grooves thus formed, and pivoted upon rods 46 running lengthways therein, are mounted nine rows of stops 45 which are normally pressed outwards by springs 54. When the escapement mechanism brings a row of stops to the setting- point, the particular stop thereof that is opposite the displaced member of a series 66 virtually forming the rear ends of the keyrods is turned over thereby and locked by a spring bail 58, as shown in Fig. 13. When the various stops in the rows have been thus set, the main operating-mechanism allows the slides 213 to move forward until the projections 222 thereon are arrested by the displaced stops. A cam 1196, Fig. 36, upon the main operating- shaft of the machine draws slightly rearwards a frame carrying alining-pawls 810 when the main slides 813 have completed their forward movements and are arrested by the stops; at the same time the pawls are pressed downwards by springs into engagement with the ratchet racks upon the slides, which are thus moved slightly rearwards, in order to aline them and to relieve the cylinder stops of pressure, previous to resetting. Selecting denomination.-Depression of any key effects, by the aid of a universal member, a rearward movement of a rod 29, Figs. 21 and 23, which co-operates with two hooked members 67, 69 to release a transverse lever 76 which rises by spring action and allows the tail 81<a> of a pivoted lever 81 to engage between nuts upon the rod 29, thereby locking the rod in rearward position. The left end of the lever 76, Fig. 23, rises until the upper end 88<b> of a pawl 88 pivoted upon the lever is arrested by one of five escapement-stop pins 92 ... 95, Fig. 10, normally projecting, but withdrawn by depression of one of the denomination-selecting keys, or, in the case of the singlestep pin, alternatively by depression of one of the numeral keys. The lower detent end of the pawl is thereby thrown into engagement with a ratchet sector 97, Fig. 21. carrying also a pawl 89 into gear with a fixed ratchet 91, Fig. 23, and the rotation of the ratchet sector thus produced releases a lug 101 upon a lever 73, the movement of which couples the operating-motor to the stop-cylinder shaft, and the cylinder, through the agency of the ratchet 91 and pawl 89, returns the lever 76 until the pawl is disengaged by the action of a fixed projection. Simultaneously the pawl 88 is disengaged and the lever 81 freed from the rod 29, which returns and releases the depressed key, while the return of the lever 73 declutches the motor. The differential return movement of the lever 76, determined by the selection of an escapement stop-pin, thus controls also the movement of the ratchet 91 and therewith the stop-cylinder. The stop-pins are arranged to overlap so that when the five-stop key is depressed four of the pins are withdrawn. In a modified arrangement, Fig. 29, the depression of one of the denomination-selection keys or of a numeral key displaces a stopmember, and allows a rod 1215, to which is secured a plate 1214 having a stepped rear end, to move rearwards under the action of a spring to a distance of from one to five steps according to the particular key depressed. Moving with the rod is an upright lever 1231, carrying a toothed segment 1234 at its upper end, and co-operating with a second lever 1245 which controls the clutch for driving the stop-cylinder spindle, as before. During the movement of the stop-cylinder the arms 1235 of a spider upon the cylinder restore the toothed segment, step-by-step, the rod 1215 being correspondingly held by pawl-and-ratchet parts at the keyboard end, until it is completely reset and the motor declutched. In this way the links connecting the denomination keys with the escapement are replaced by a single rod. Operating by motors.-The clutch connexions between the motor and the stop-cylinder are broken when a certain wheel is arrested, but are made when that wheel is free to rotate. Movement of the lever 73 is arranged to press a slotted member against the flanged periphery of the wheel, or to release it.