WINCH BASICS: How Planetary Gear Reduction Works
by Larry Walton
Most medium-duty electric winches employ several sets of planetary gears to accomplish the gear reduction needed to produce the pulling power to move tons of truck.
“Each set has a certain reduction and those reductions combined create the overall gear reduction,” says Darren Johnson, design engineer for Warn Industries.
Johnson explains it in basics: The winch motor turns a shaft connected to the first sun gear, which is engaged in a set of planetary gears that reduce the gear ratio.
This first set of planetary gears transfers torque through a carrier into another sun gear, which turns the next set (or stage) of planetary gears.
This process is repeated through three stages of planetary gears that multiply the power through gear reduction at each stage.
Understanding the function of planetary gearsets helps in their repair.