Patent GB-1195802-A (GB)
Title: Printer
IPC: B41J11/04
Filed: 1968-04-09
Abstract: 1,195,802. Selective printing. INTERNATIONAL BUSINESS MACHINES CORP. 9 April, 1968 [17 April, 1967], No. 16914/68. Heading B6F. Index-setting arrangements: variable stroke roller impression arrangements.-A selective printer having an interchangeable type fount disc D, Fig. 1, which is set manually for character selection, is provided with an impression roller 40, Fig. 2, whose stroke along a rectilinear path 41 is varied proportionally to the width of character to be impressed. In operation a character is selected by rotation of disc D to a printing station 12 at which the character selected is aligned (by means not shown) and the printing cycle is then started by depression of a printing key 15 which releases a single revolution clutch 91 to drive a shaft 31 provided with a roller actuating cam 52. The cam 52 rocks a follower 53 associated with a linkage 54 to draw a link 56 to the right, the link 56 displacing a constant throw roller driver 50 which rooks the roller 40 by means of a latch 60 pivotally mounted on a yoke 43 which carries the roller 40. The stroke of the roller along the path 41 is interrupted by a control bracket 64 articulated to the latch 60 and disengaging the latter from the driver 50 when a lug 65 strikes a pawl 66 which is moved into path of the lug 65 a predetermined distance corresponding to the width of the character to be impressed. The lug 65 is displaced by a probe 70 which abuts a ledge D 2  on a letter-spacing disc D 3  fast with the type fount D, the probe 70 which is articulated to an arm 71 fast with a shaft 73, moving towards the ledge D 2  when the link 56 is displaced rightwardly under the influence of a pin 74 which follows the displacement of the link and which is articulated indirectly to the shaft 73 by a bracket 21 biased clockwise by a spring 76. When the probe 70 abuts the ledge D 2  the rotation of the shaft 73 is arrested and the lug 65 is displaced by a distance corresponding to the letter-space of the character selected. Following arrestment of the roller 40 the driver 50 continues along its constant stroke 51, the return movement of the driver being induced by a spring 55. The roller 40 is restored to its rest position by the driver 50 which engages a lug 46 on the roller yoke 43. Stroke of the roller 40 is also varied by a cam 59 which is engaged by the cam follower 53 when a lever 30 displaces the driving-shaft 31 in the case when a disc D with smaller type characters is fitted on to the disc support 11. Impression of the roller 40 is varied by a lever 16 which actuates a pair of cam-shafts 42 to vary the pressure exerted by the roller 40 on to a record tape 13. Letter-spacing arrangements.-At the start of the printing cycle, following depression of the printing key 15, a clutch 82 which drives the tape 13 in a letter-spacing direction is disengaged by an arm 83 which displaces a shaft 81 against the bias of a spring 85. During the return stroke of the impression roller driver 50 the clutch 82 is engaged with the tape spool 80 to rotate it anti-clockwise, through a segment 87, by an amount corresponding to the width of the character selected and predetermined by the displacement of a link 75 in consequence of restoration of the pin 74, bracket 21 and probe 70 by the link 56. Ink ribbon mechanism.-An ink ribbon 14 is fed incrementally by a feed mechanism which is identical with that which effects letter-spacing displacement of the record tape 13.