This simulator inspects alternating link plates, rollers and toothed sprockets on a guarded roller-chain drive bench. Adjust driver and driven tooth counts, driver speed, input torque demand, requested shaft spacing, prescribed transmission efficiency and measured pitch elongation, then compare tooth ratios, chain-length selection and the effect of wear on engagement.
• A real-time 3D cutaway workbench of the driving sprocket and keyed shaft, driven sprocket and load coupling, roller chain with pins and alternating link plates, slotted support with screw center-distance adjustment, drip lubricator and oil collection tray, removable mesh chain guard with shaft bearings, and a separate pitch-gauge inspection fixture, with home view, focus-selected-part, show-full-enclosure, exploded view, auto-rotate, expand and show/hide labels controls. • Two action controls: start drive and stop drive. • Playback controls: pause/resume, 0.1 s and 1 s step advances, and five playback speeds (10× and 100× slow motion, real time, 10× faster, one minute per second). • A Curves & measurements tab with a live mean input/output power chart, a mean output-speed history chart, the full model equations (speed ratio, mean chain speed, pitch radius, approximate chain-length/center-distance formula, power and torque transmission, chordal-variation indicator) and snapshot measurement readouts covering output speed, speed ratio, chain speed, mean chain pull, output torque, input/output/loss power, selected pitch count, estimated center distance, tooth-engagement frequency, chordal variation and measured worn pitch. • An Experiments tab with four guided fixtures (nominal 18:36 reduction, equal tooth counts, small driving sprocket, inspect elongated pitch) and a Model verification bench that runs independent deterministic checks against a fresh model without disturbing your live trial, plus a timestamped event log and a copyable trial report. • A Learn & assess tab with guided lessons, a knowledge-check quiz with reset, and a written model-scope statement with a technical reference link.
A chain drive is a positive-engagement mechanism, not a friction drive like a belt: each sprocket advances exactly one chain pitch per tooth it engages, so there is no slip. This makes the mean speed ratio a simple function of tooth counts — driven speed equals driver speed times the ratio of driver teeth to driven teeth, independent of chain tension or load (within the drive's capacity).
Because a chain wraps a sprocket as a polygon rather than a true circle, fewer teeth on the driving sprocket produce more pronounced chordal action — a cyclic speed variation within each revolution as successive chain pitches engage at slightly different effective radii. The simulator's chordal-variation indicator captures this geometric effect, though the 3D animation itself uses mean transport speed.
Selecting a chain length is a discrete problem: roller chains commonly use an even number of pitches so the two chain ends join cleanly, and the simulator solves an approximate length equation to pick the nearest even pitch count and the corresponding estimated center distance for your requested shaft spacing.
A separate enlarged pitch gauge compares the nominal 12.7 mm pitch against a measured elongation caused by pin and bushing wear. This is an inspection trigger, not a universal discard limit, and worn pitch does not behave like smooth belt slip — it degrades tooth engagement and, in a real drive, can eventually cause skipping, which this model flags but does not simulate directly. The overall model is a mean-speed positive-drive representation without contact mechanics, tension oscillation, chain sag or strength rating.
A chain engages sprocket teeth positively — each tooth advances the chain by exactly one pitch, with no friction-dependent slip. This is why the mean speed ratio in the simulator depends only on the driver-to-driven tooth-count ratio, unlike a belt drive where tension and friction limits can cause slip.
A chain wraps around a sprocket as a polygon rather than a perfect circle, so the chain's effective radius varies slightly as each pitch engages, producing a small cyclic speed variation called chordal action. Fewer teeth make this polygon more pronounced, increasing chordal variation — the simulator's indicator reflects this even though the visible animation uses mean speed.
No. Pitch elongation from pin and bushing wear degrades how well the chain seats on unworn sprocket teeth, and in a real drive can eventually cause the chain to skip a tooth. The simulator flags this with a separate inspection gauge rather than modeling it as a smooth, continuous speed loss the way belt slip would behave.
No. It is a mean-speed positive-drive model at nominal pitch — it excludes contact mechanics, chain tension oscillation, sag, strength rating and true wear evolution, and center-distance estimation excludes installation slack. A real chain drive selection requires manufacturer horsepower ratings and full engineering design procedures.