| 91 / | HD | MOTORS: EXPANSIBLE CHAMBER TYPE |
| 418 | DF | WITH MOTIVE FLUID VALVE {32} |
| 449 | DF | .~ Plural separately controlled waste passages for single working chamber {2} |
| 450 | | .~.~ One passage controlled by inlet and exhaust valve {1} |
| 451 | DF | .~.~.~> Another passage controlled by motive fluid pressure or flow responsive valve (468) |