GB1142528A - Printing apparatus - Google Patents

Abstract

1,142,528. Selective printers. INTERNATIONAL BUSINESS MACHINES CORP. 7 Dec., 1966 [30 Dec., 1965], No. 54788/66. Heading B6F. Type-wheel machines; electric input signal arrangements; summation type selecting mechanisms; relay actions.-A selective printer having a type carrier 6, Fig. 1, rotatable about a vertical shaft 5 for character selection in accor. dance with electrical binary code signals representative of the character and supplied by a data source control 4 through lines 15, 16, 17 to electromagnets 18, 19, 20 which actuate respective pawls 43, 42, 41 by armatures 54, 53, 52 engaging and displacing ratchet wheels 22, 23, 24 associated with summation gears is provided with a resetting ratchet wheel 27 which disconnects the summation gears from the set type carrier 6 so that the latter is restored under action of spiral spring 7 to its home position without concomitant resetting of the summation gear. In operation drive 38 continuously drives a shaft 29 having fixed thereon a number of cams 32, 33, 34, one for each electromagnet 18, 19, 20 which when energized selectively by lines 15, 16, 17 cause a respective pawl 43, 42, 41 to be oscillated into engagement with associated ratchet wheel 22, 23, 24 and thereby displace the shaft 5 angularly through the intermediary of epicyclic gears 60, 58, 59 or 63, 64, 65. By way of example actuation of pawls 43, 44 results in angular displacement of the shaft 5 by three steps due to displacement of the ratchet wheel 22 fast with the shaft 5 by one step and displacement of the ratchet wheel 23 loosely mounted on hub 62 and rotating the shaft the corresponding amount through epicyclic gears 57, 58, 60 and ratchet wheel 22. The resultant angular displacement is transmitted to the type carrier 6 by a ratchet wheel 25 fast with the shaft 5 through a pawl 26 and reset ratchet wheel 27 whereby the type carrier is rotated against the bias of resetting spring 7. Hammer impression arrangements.-A hammer 8, Fig. 1, is actuated by an electromagnet 9 to press a record medium and transfer medium 11 against the type carrier. Resetting arrangements.-Following impression the type carrier is reset by transmission of a signal from the data source 4 to a resetting electromagnet 45, Fig. 1, whose armature pivots the cam oscillated pawl 40 into engagement with the resetting wheel ratchet 27 which is rocked in the direction of arrow 46 to disengage pawl 26 from the ratchet 25 and thereby allow the type carrier 6 to move under the spring bias to its home position. When the electromagnet 45 is de-energized spring 49 attached to pins 39, 50 on the type carrier 6 and ratchetwheel 27 causes the pawl 26 to re-engage the ratchet wheel 25 through the intermediary of a pin 37 disposed in a radial slot of a recess 27a in the ratchet wheel 27. Composite type selecting actions.-In another embodiment the type carrier 6, Fig. 3, may be replaced by a rotatable and slidable type cylinder 73, whereby the sliding movement for character selection is effected by a mechanism 95 which is identical with the mechanism for rotary character selection on type carrier 6.