What is a planetary reduction drive?

A planetary reduction drive is a small scale version using ball bearings in an epicyclic arrangement instead of toothed gears. Reduction drives are also used to decrease the rotational speed of an input shaft to an appropriate output speed. Reduction drives can be a gear train design or belt driven.

Can planetary gears be back driven?

A 10:1 is very easy to back drive. The largest ratio planetary gearbox I have back driven was a two stage 100:1. On a side note, if you are driving the gearbox with a DC or servo motor you will probably have to disable the dynamic braking to back drive it.

What is a planetary gear system used for?

Generally, planetary gears are used as speed reducers. They are used to slow down motors and increase the torque. Torque is the working power of the machine. But we’ve seen our planetary gears turned around to be used as speed increasers, too.

How does a planetary drive work?

In a wheel drive planetary gearbox, the sun gear drives the surrounding planetary gears which are fixed to a carrier. When the sun gear is driven, the planet gears rotate the outer ring gear. The wheels can be mounted over the housing of the gearbox. Wheel drive planetary gears can deliver up to 332,000Nm torque.

Which gear has highest speed reduction?

Worm gears are perhaps the most costeffective reduction solution, but usually have a minimum 5:1 ratio and lose considerable efficiency as ratios go higher. Bevel reducers are very efficient but have an effective speed reduction upper limit of 6:1.

Which gear is used for high speed reduction?

Worm Gear Drives
Worm Gear Drives: Worm gears are devices that transmit power through non-intersecting, non-parallel shafts. They are primarily used for high-speed reduction.

Are planetary gears more efficient?

In addition to their durability, planetary gear motors also provide a higher efficiency over spur gear motors. Due to the construction of a planetary gear head, the length of a planetary gear motor is usually longer and narrower than spur gear motors.

How efficient are planetary gears?

The efficiency loss in a planetary gear train is typically about 3% per stage. This type of efficiency ensures that a high proportion (about 97%) of the energy being input is transmitted through the gearbox, rather than being wasted on mechanical losses inside the gearbox.

What machines use planetary gears?

Planetary gear train (PGT) has been widely used in the transmissions of helicopters, automobiles, wind turbine, aircraft engines, etc. The main advantages of this transmission are its high efficiency, its compactness, its large transmission ratio and its large power-to-weight ratio, etc.

How do planetary gears increase torque?

The planet gears are mounted on a joint carrier that is connected to the output shaft. The rotational speed of the output is lower than that of the drive, and the torque of the output is higher in reverse proportion. The more gear wheels mesh with each other, the higher the torque.

When large gear reductions are needed which gears are used?

Worm gears
Worm gears are used when large gear reductions are needed. It is common for worm gears to have reductions of 20:1, and even up to 300:1 or greater.