GB844526A - Improvements in record-controlled printing machines - Google Patents

Abstract

844,526. Typewriters &c. INTERNATIONAL BUSINESS MACHINES CORPORATION. Jan. 22, 1957 [Jan. 25, 1956], No. 2234/57. Class 100(4) A punched card controlled typewriter having a type-wheel positioned by a magnetically controlled clutch has improved electrical card sensing means in which brushes sense holes in a card to select groups of type. Individual type are selected on sensing further holes. Also, additional groups of type are selected when certain combinations of holes (i.e. 8-4 and 8-3) are serially sensed. Cards 10, Fig. 1, having twelve punching positions per column are used, and twelve brushes 19, statically read record holes 12, (R), 11, (X), O, 1-9 in a column. Impulses are transmitted to related sensing brushes in the order 9-1, O, X, (11), and R, (12) as a brush wipes over the emitter contact points. Groups of type, Fig. 4, are selected by impulses 8-4, 8-3, completed serially through the two appropriate holes, and 9-0. An individual type in a group is selected by the second O, X or R impulse for a letter or the N impulse for a digit. A printing control magnet 26, Fig. 3, when energised by an impulse through a hole initiates the differential anticlockwise rotation of a type wheel 25 through members 28, 27, 29, 31, 32, arms 37 and members 39, a clutch pawl 55, a fluted tube 41, and gears 43. An armature knock-off cam 75 prevents an armature 28 from sticking, through members 76, 78, 79, 27. A clutch release arm 39 is returned to pawl engaging position, as in Fig. 3, by a finger 82 moved by a cam and follower 86, 85, 84. A second impulse to a magnet 26 from zone holes O, X, R, or from the N impulse generating cam selects a character from a group by engaging the printing clutch 98, 99 through members 28, 27, 79, 78, 77, 91 and pawl 94. As a cam 65 revolves, projection 63 engages projection 62 and rocks a frame 60 pivoted at 61 and a type-wheel 25 towards a platen 67 to print. A cam 95 prevents this sequence occurring in response to the first impulse to the magnet 26. The type wheel 25 rotates more slowly during character selection from a group as described in Specification 605,132. Brushes 114-117, Fig. 5, rotate half a revolution per machine cycle. The circuit through magnet 26 is completed as follows:- Positive line 120, segment 112, brush 116, wire 122, brush 117, 8-4 or 8-3, wires 123, 129, hole 8, brush 19, plate 11, brush 19, through either hole 4 or 3, and either wires 130, 131 to 8-4 or 132, 133 to 8-3, from either of these through brush 114, wire 126, brush 115, segment 113, wires 107, 106, 105 and magnet 26 to negative line 121, and similarly for points 9-1, O, X and R. The N impulse is transmitted under control of CR1 cam contacts. Specification 632,724 also is referred to.