The Little Giant locomotive injector uses a separate lift steam valve and handle-controlled nozzle passages. Explore those control relationships and the movable combining tube described in Hiscox figure 383.
Little Giant Injector Control-State Explorer
Use the two illustrative controls to inspect the states described by Hiscox. They do not reproduce a real starting sequence, internal calibration, capacity, pressure limit or safe operating procedure.
Equation Used
- The section is schematic and not dimensionally faithful.
- Control states paraphrase the historical source; their slider positions are illustrative.
- Pressure, temperature, capacity, clearances, timing and operating procedure are intentionally outside the model.
The two controls show whether the illustrated lift valve, injection nozzle and lift-nozzle ports are open or closed. Their positions identify component states, not calibrated operating settings.
Documented control relationships
Hiscox states that opening a separate steam valve starts the lift. Movement of the handle then opens the injection nozzle and closes the lift-nozzle ports. The forcing or combining tube is movable for regulation by a screw and yoke.
The animation labels those parts and states in a schematic section. It does not reconstruct unreported dimensions, flow, pressure, timing or a complete operating sequence.
Historical mechanism study
This page is suitable for identifying the documented parts and their relationships. It is not a boiler-feed selection, commissioning, troubleshooting or operating guide.
What the controls show
The controls select the illustrated valve and nozzle states. Flow capacity requires the exact injector model, manufacturer data and specified installation conditions; it cannot be calculated from these state selections.
Reading the state explorer
The lift/start position displays the injection nozzle closed and the lift-nozzle ports open. Moving the illustrative handle beyond mid-travel displays the stated opposite relationship. That threshold is only a user-interface switch, not real handle calibration.
Model boundary and safety
The drawing does not establish steam pressure, water temperature, lift, delivery head, capacity, nozzle dimensions, clearances, adjustment, start-up procedure or safe limits. Steam and boiler-feed systems can cause severe injury. Use the exact equipment manual, applicable code and trained personnel.
Little Giant injector questions
Does this injector have a lifting stage?
Yes. The cited Hiscox description says the lift starts when the separate steam valve is opened.
Does the slider show the real operating sequence?
No. It is a labelled state comparison only.
Can the diagram determine capacity?
No. It identifies control states. Flow capacity requires equipment-specific performance data.
Historical references
- G. D. Hiscox, Mechanical Movements, Powers, Devices and Appliances, figure 383: separate lift steam valve, handle-controlled injection nozzle and lift ports, and screw-and-yoke combining-tube adjustment.
- Locomotive Appliances: contemporary component list and description of the movable combining tube and its control.
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