Combinations of gears give large ratios; planetary trains offer compact high reduction.
Simple train ratio = product of driven teeth / product of driving teeth. Compound trains use shafts with two gears. Planetary trains with sun, planets, ring and carrier give high ratios compactly using the tabular method.
A 3:1 and a 4:1 stage give 12:1 overall.
Gear trains reach large ratios and compact layouts that a single pair cannot achieve, so they are used in gearboxes and vehicles.
Combinations of gears give large ratios; planetary trains offer compact high reduction.
Gear trains reach large ratios and compact layouts that a single pair cannot achieve, so they are used in gearboxes and vehicles.
Multiply the ratios of each stage, taking into account the direction of rotation at each mesh.
They provide high ratios in a compact coaxial layout and distribute load across several planet gears.
Typical applications include designing a reduction gearbox for a robot joint, choosing a planetary gearbox for a compact drill drive and calculating the ratio of a bicycle drivetrain with several sprockets.
Study "Gears" first (topic 86 of 106 in Engineering Mechanics). It covers the groundwork this topic builds on.
Idlers reverse direction only. Ratio multiplies per stage. Used in transmissions.
A 3:1 and a 4:1 stage give 12:1 overall.
The next topic is "Belt and chain drives", which builds directly on this one.
It is classed as Advanced in Engineering Mechanics (topic 87 of 106). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Engineering Mechanics.
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