How to match the reducer with the servo motor

Does the servo motor need to be matched with a planetary reducer? Then how to match the reducer with the servo motor in production?

1: Speed ​​ratio

The reduction ratio of the reducer is roughly the result of dividing the rated speed of the motor by the final output speed. For example, if the final output speed is 200RPM and the rated speed of the motor is 3000RPM, then the speed ratio of the reducer is preferably around 1:15. The final output speed depends on the working conditions.

2: Torque

The rated torque of the reducer must be greater than or equal to the product of the motor's rated torque and the reduction ratio. Assuming the motor's rated torque is 10N.M and the reduction ratio is 15, the rated torque of the selected reducer model must be greater than 10*15=150N.M.

3: Accuracy

The return clearance (backlash, clearance or rotary clearance) of the reducer depends on the specific working requirements. Generally speaking, the clearance used with a servo motor should not be greater than 20 arcmin. Single-stage reduction that can be less than or equal to 3 arcmin is generally a high-end product.

4: Specifications

The cross-sectional dimensions of the reducer are generally similar to those of the motor. For other parameters, it is best to refer to the instructions of the selected brand. The technical sample generally indicates the selection steps and calculation examples. The specific models are expressed differently for each brand. Usually, they are roughly expressed by the output flange size or cross-sectional size, generally with specifications of 40/42, 50/60, 70/80, 90, 115/120, 142, 160, 180, 220, 240, etc.

General principles:

Small servo motors can be equipped with large reducers, but large motors are generally not equipped with small reducers.

For the same specification, the higher the rigidity, the better the quality, so our process is hard tooth surface cutting process.

Servo motor selection:

Speed ​​(select as needed)

Torque (calculate the torque required by the servo motor based on the load structure, weight and speed)

Moment of inertia (this parameter is related to the running accuracy of the servo on the mechanical structure and is calculated by the weight of the load structure)

Generally, a certain margin, that is, the safety factor, must be left.

Use these three parameters in combination with the selection sample to select the model of the servo motor.

Reducer selection:

Reduction ratio (determined by the ratio of the motor speed to the final output speed, the ratio of the final output torque to the motor torque, and the square root of the ratio of the mechanical moment of inertia to the motor moment of inertia)

Rated load torque (the final output torque should not be greater than the rated torque of the reducer, which is related to the life of the reducer)

Accuracy (select appropriate accuracy requirements according to user needs)

Installation matching dimensions (the matching installation between the load and the reducer, and the matching installation between the motor and the reducer, etc. are determined according to the product drawings)

The above are the general parameters that need to be determined when selecting servo motors and reducers.