Explanation of some common terms about motor and reducer

1、 Motor

① Starting torque

The torque generated at the moment when the motor starts. Generally, the starting torque of single-phase motor is 60-70% of the rated torque, and the starting torque of three-phase motor is 2-3 times of the rated torque.

Since the starting torque of single-phase motor is less than the rated torque, the output torque of single-phase motor shall be the starting torque when calculating the driving force for constant load application.

② Rated torque

The torque that the motor can continuously output under rated voltage and rated frequency.

③ Rated speed

Speed of motor under rated voltage, rated frequency and rated output power.

④ No load speed

Speed of motor under rated voltage, rated frequency and no load.

⑤ Stop over rotation

The number of turns that the motor rotor shaft continues to rotate due to inertia from the moment when the power supply is cut off to the time when it stops completely.

⑥ Braking force

The force applied to the motor rotor shaft to quickly decelerate the motor output shaft, stop the braking, or keep the motor output shaft in the original state.

The braking torque of the electromagnetic braking motor is 1.2~1.8 times of the rated torque.

The braking torque of the damping motor is 10% of the rated torque.

⑦ Gear shaft

The rotor shaft of the motor is in gear shape, which is used for matching and connecting the reducer.

⑧ Circular axis

The rotor shaft of the motor is cylindrical in shape, which is used for the motor alone and cannot be connected with the reducer.

2、 Reduction gearbox

① Allowable torque

When the motor is decelerated by the reduction gearbox, the output torque at the motor end is amplified by the reduction gearbox by a multiple of the reduction ratio. When the reduction ratio is large, such as 1:180, the output torque of the motor is amplified by 180 times. In theory, if the reduction gearbox has a large load, the motor can drive the load. However, because the mechanical strength of the reduction gearbox cannot bear the load, the reduction gearbox will be damaged. The maximum load torque to ensure that the reduction gearbox is not damaged is the allowable torque of the reduction gearbox.

② Grayson spiral gear

The gear is a 90 degree transmission with high transmission efficiency, no self-locking and long service life. It is mainly used for automobile rear axle transmission and is the most advanced 90 degree transmission structure.