Industry news|2022-04-12| admin
The combination of servo motor and gearbox is a very common transmission cooperation. The gearbox can play a good role in increasing torque and reducing speed, so that the transmission mechanism has a very suitable output power and optimizes the quality of machinery or workpieces. So what parameters are required for the selection of servo motor gearbox in production, let's take a look.
1: Speed ratio
The reduction ratio of the gearbox is roughly selected by dividing the rated speed of the motor by the final output speed. For example, if the final output speed is 200 rpm and the motor rated speed is 3000 rpm, the speed ratio of the gearbox is about 1:15. Final output speed depends on operating conditions.
The output torque of the gearbox is also the required torque we get when we choose the gearbox. We choose the gearbox because we hope that the motor rated torque of the gearbox is the smallest, and the gearbox can obtain a larger torque output by increasing the torque. Therefore, after determining the torque required by the mechanism, and then comparing the selected servo motor torque, the ratio of these two torques is the speed ratio of the gearbox torque to be selected. We generally allow some headroom for the final torque, and the gear ratio will be slightly larger than required.
Assume that the rated torque of the motor is 10N. m and the reduction ratio is 15, the rated torque of the selected gearbox model should be greater than 10 * 15 = 150 N.m
The precision of the gearbox can be selected according to the precision required by the mechanism, and can be matched according to the corresponding parameters. The return clearance of the gearbox (backlash, backlash or swing clearance) depends on the specific job requirements. Generally speaking, the gap used with the servo motor should not be greater than 20arcmin, and the single-stage deceleration can be less than or equal to 3arcmin, which is generally a high-end product.
The cross-sectional size of the gearbox is generally similar to that of the motor. For other parameters, it is best to refer to the description of the selected brand. Technical samples generally describe selection steps and calculation examples. Specific models are represented by different brands. Generally expressed by output flange size or section size, generally 40/42, 50/60, 70/80, 90, 115/120, 142, 160, 180, 220, 240, etc.
Small servo motors can be equipped with large gearboxs, while large motors are generally not equipped with small gearboxs.
The higher the hardness of the same specification, the better the quality, so our technology is hard tooth surface cutting technology.
Servo motor selection:
Speed (select as required)
Torque (According to the load structure, weight and speed, calculate the torque that the servo motor needs to output)
Moment of inertia (this parameter is related to the servo running accuracy on the mechanical structure, calculated by the weight of the load structure)
Generally, there must be a certain margin, that is, the safety factor.
Combine these three parameters and select samples to select the model of the servo motor.
Selection of gearbox:
Reduction ratio (determined according to 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)
Bearing torque (final output torque should not be greater than the rated torque of the gearbox, which is related to the life of the gearbox)
Accuracy (select the appropriate accuracy requirements according to user needs)
Dimensions of accessories (installation of accessories between the load and the gearbox and the installation of accessories between the motor and the gearbox are determined according to the product drawings)
The above is the relevant knowledge of the parameters required for the selection of the servo motor gearbox. The parameter configuration of the gearbox such as torque and accuracy is also very important in the selection, and must be paid attention to in the selection process.