A planetary gearbox is a commonly used reducer consisting of the planet gear, sun gear, and outer ring gear, whose structure has the functions of shunting, deceleration, and multi-tooth meshing to improve the output torque, better adaptability, and work efficiency. The sun gear is usually placed in the center, and the planet gears orbit around the sun gear, receiving torque from it. The outer ring gear (refers to the lower housing) meshes with the planet gears. ZHAOWEI provides optional motors, such as brushed DC motors, DC brushless motors, stepper motors, and coreless motors, which can be matched with micro planetary gearbox for better performance.
Planetary Gearbox
Modular Gearbox

Advantages of Planetary Gearbox
1. High torque: With more teeth in contact, the mechanism can transmit and withstand greater torque in a more uniform manner.
2. Durable and efficient: The bearing can reduce friction by connecting the shaft directly to the gearbox. It allows for better rolling and smooth running, simultaneously enhancing efficiency.
3. Impressive precision: The rotation angle is fixed, which improves the accuracy and stability of the rotation movement.
4. Compact size: The planetary gear motor can be compact and small due to the planetary structure, in which multiple gears mesh together and orbit around a sun gear.
5. Low-noise: The multiple gears enable more surface contact. Rolling is much softer, and jumps are virtually nonexistent.
Module | Voltage (V) |
Reduction Ratio | Rated Speed(rpm) | Rated Torque (gf.cm) |
Overall Length (mm) |
---|---|---|---|---|---|
3.4mm DC Gear Motor | 3V | 5-625 | customization | 50gf.cm | 10.75-15.25mm |
4.3mm DC Gear Motor | 3V | 6-1296 | customization | 140gf.cm | 11.78-16.32mm |
6mm DC Gear Motor | 3-12V | 4.8-1707.9 | 4-1563rpm | 250-600gf.cm | 23.7-30.9mm |
8mm DC Gear Motor | 3-12V | 3.6-809.1 | 14-3361rpm | 50-750gf.cm | 23.1-31.2mm |
10mm DC Gear Motor | 3 - 24V | 3-809 | 17-3917rpm | 500-1000gf.cm | 24.7-34.0mm |
12mm DC Gear Motor | 3-24V | 4-1296 | 6-1875rpm | 200-2000gf.cm | 24.5-35.9mm |
16mm DC Gear Motor | 3-24V | 4-1296 | 6-1875rpm | 3000-5000gf.cm | 38.4-48.3mm |
20mm DC Gear Motor | 3-24V | 4-1296 | 6-1875rpm | 6000-10000gf.cm | 42.7-58.6mm |
22mm DC Gear Motor | 3-24V | 4-1296 | 6-1875rpm | 8000-15000gf.cm | 57.5-79.4mm |
24mm DC Gear Motor | 3-24V | 4-1296 | 6-1875rpm | 15000-20000gf.cm | 49.3-69.45mm |
28mm DC Gear Motor | 3-24V | 4-1296 | 5-1658rpm | 15000-40000gf.cm | 58.1-83.6mm |
32mm DC Gear Motor | 3-24V | 16-1078 | 7-469rpm | 30000-50000gf.cm | 78.2-98.2mm |
38mm DC Gear Motor | 3-24V | 4-1526 | 4-1525rpm | 80000gf.cm | 87.7-126.7mm |
Customization Small Gearbox
ZHAOWEI offers customer-based planetary gearbox solutions with extended choice of materials and gearbox features. Planetary gearbox can be combined with motors, including DC motor, stepper motor, and corelsss motor, to achieve high output torque, smooth output speed, and high work efficiency.
Specifications are as follows: Diameter: 3.4mm–38mm; Voltage: under 24V; Output power: under 50W; Output speed: 5rpm–2000rpm; Speed ratio: 5–1500; Output torque: 1.0 gf.cm–50kgf.cm.