A compound wheel train passes rotation through successive gear pairs. Enter three stage speed multipliers to compare the combined speed change, output period and ideal torque ratio.
Wheel Train Interactive Calculator
Enter three positive stage ratios and input speed. Ratios are defined here as output speed divided by input speed; direction, tooth counts, efficiency and loads are not solved.
Equation Used
- All ratios are positive output/input speed magnitudes.
- Stages are rigid and lossless.
- Direction and idler effects are omitted.
- Tooth counts, module, center distance, backlash and interference are omitted.
- Inertia, efficiency, strength, lubrication and life are omitted.
Ideal Three-Stage Wheel Train
The NASA simple-machines guide provides gear context. This calculator uses entered stage ratios rather than tooth geometry.
What This Calculator Represents
A lossless serial ratio comparison with each ratio defined as output speed divided by input speed.
Serial Ratio comparison
nout=ninR
T=3600/nout
tauout/tauin=1/R
Worked Scenario
Ratios 6, 6 and 7 produce 252x. At 1 RPH input, output is 252 RPH, one revolution takes about 14.29 seconds and ideal torque factor is 0.00397.
Assumptions and Limits
- Calculated: ratio product, ideal speed, period and reciprocal torque factor.
- Not calculated: tooth geometry, direction, losses, loads, strength or life.
Frequently Asked Questions
Are these reduction ratios?
No; they are defined as speed multipliers.
Are losses included?
No.
Is direction shown?
Only as an animation cue.
Are tooth counts selected?
No.
Is output torque guaranteed?
No.
Can this design gears?
No.
References
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