| 400 / | HD | TYPEWRITING MACHINES |
| 139 | DF | INCLUDING TYPE-SET-ASSEMBLAGE MOUNTED ON CARRIER AND RELATIVELY MOVABLE FOR SELECTION AND FOR IMPACT OF TYPE-FACE {11} |
| 153 | DF | .~ Imprint by movement of record-medium against type-face {3} |
| 154 | DF | .~.~ By hammer impacting record-medium against type-face on type-head (e.g., type shuttle, etc.) {3} |
| 157.1 | DF | .~.~.~ Including particular structure of hammer(s) {3} |
| 157.2 | | .~.~.~.~ Electromagnetically actuated |