| 400 / | HD | TYPEWRITING MACHINES |
|
| 545 | DF | FOR LINE-SPACING BY INCREMENTAL ROTATION OF PLATEN {15} |
| 546 | DF | .~ To facilitate condensed billing (i.e., by determining a desired limit or amount of retrograde or advance platen movement) {2} |
| 547 | DF | .~.~ Including stop structure (e.g, traveling stop, etc.) {1} |
| 547.1 | DF | .~.~.~ For arresting platen at limit of both retrograde and advance movement {2} |
| 547.3 | DF | .~.~.~.~ By lever or push-rod drive for platen {2} |
| 547.4 |  | .~.~.~.~.~ Via gear drive {2} |
| 547.5 | DF | .~.~.~.~.~.~> Including lever on axis transverse to platen axis |
| 547.6 | DF | .~.~.~.~.~.~> Including relatively adjustable coaxial gear segments |