3 min readMay 23, 2022

What is an SMD Planetary Gearbox?

A Planetary Gearset is a gearset consisting of Sun Gears, Planetary Gears, A Carrier and a Ring Gear. The Sun gear is located at the centre and Driven and moves the Planet Gears locked in the Carrier. This Construction of Gears looks like a Solar system from which the name derives i.e. Planetary Gearbox. Our Planetary gearbox is available in Single Stage and Double Stage and is available in 2 Variants i.e. with Output Shaft and Flange End. The sizes available with SMD Planetary Gearbox are SNP40, SNP60, SNP90, SNP120, SNP150. Our Clients use Planetary Gearbox in different ways, Planetary gearbox is Generally used as a Speed Reducer but in some applications, it can be used as a Speed Increaser too.

SMD Planetary Gearbox Working
SMD Planetary gearbox Structure

Advantages of SMD Planetary gearbox?

1) High Stability.

Even distribution of mass and rotational stiffness creates greater stability.

2) High Torque Density.

When more Planet Gears are available in the Gearbox it carries more load and high Torque stability.

3) Compact Size.

The inline Planetary Structure and Common Axis makes this Gearbox compact in Size.

4) Cost Effective.

SMD Planetary Gearbox offers much more competitive price than other competitors and also helps in customization and Installation Support.

5) High radial Loads.

In Comparison to other Gearset in Manual Transmission, SMD Planetary gearboxes are strong enough to carry High Loads even in a compact size.

6) High Efficiency.

High proportion of the energy in input is transmitted through the gearbox, rather than being wasted on mechanical losses inside the gearbox. SMD Planetary Gearbox full and constant meshed Ratio permits quick gear ratio change.

7) Designed to be used with Various Servo Motors.

SMD Planetary gearbox provides Customized solutions by providing variation in Frame Size, Mounting Hole, and keyway according to the Customers Servo Motors.

8) Easy Installation.

SMD Planetary gearbox has Sealed Shut and total enclosed design for easy Installation and Self Lubrication.

SMD planetary gearbox Calculation and Working

Things we need to know while selecting SMD Planetary Gearbox?

1) Backlash.

Backlash is the angle at which the output shaft of a gearbox can rotate without the input shaft moving or the clearance between the teeth of two adjacent gears. In Precise applications Like Automation, Robotics, Backlash should be considered.

2) Ratio.

Gear ratio is the correlation between the number of teeth of two different gears. The Selection of the Ratio depends upon the application and the Motor Rpm like what output the customer needs.

3) Speed.

Speed is proportional to the Gear Ratio of the Gearbox. If the input gear has more teeth than the output gear, the result will be an increase in speed at the output shaft. The higher the ratio the lower the output speed will be and vice versa.

4) Output Torque.

Gear reduction reduces the relatively high rotational speed of the motor, delivering a lower rotational speed at the output end. Output torque is an important parameter when choosing a planetary gearbox.

5) Peak Overload Torque.

Peak Overload Torque should also be considered while selecting of the gearbox as it is a short term overloading of permitted output Torque.

6) Secondary Factors.

Factors such as noise, Corrosion, Delivery Time, Price should also be considered.

SMD Planetary gearbox Applications?

1) Automobile.

2) Wind Turbines.

3) Conveyors.

4) Material Handling systems.

5) Track drives.

6) Mixing Equipment.

7) Pumps.

8) Laser Cutting Machines.

9) CNC machines.

10) Gantry Machines.

11) SPM

12) Medical Equipment.

13) Robotics.

14) Hoists and Cranes.

15) Agriculture Equipment.

SMD Planetary Gearbox ( SNP Series )




Our Company Name SMD stands for SEIMITSU MOTION DRIVES as a trailblazer in the solution provider of various types of industrial Gearbox in Taiwan.