What should I bring to CDC at the age of 3

1. It should be prepared, but if it should be, it should not be much, but it should be prepared with ID card and other documents.

2. The earliest bus from Ningbo south bus station to Xiangshan starts at 6 am; The latest departure from Xiangshan passenger transport center to Ningbo south bus station is 5:25 p.m.

3. Motor selection:

the main technical index of motor is rated torque / power / inertia

since you have used the turbine to decelerate, it means that your working speed is very low, so you don't need to consider the inertia moment of quick start, and think that your mechanical system works at a constant speed

then you can calculate the average speed of the weight at work × 3000n to get the output power of the system

then the efficiency is determined. First of all, the efficiency of the turbine vortex bar must be considered, because the turbine vortex bar transmission is a low efficiency transmission. There are bearings, screw... The total efficiency of the system is obtained by multiplying the mechanical efficiency of all intermediate links

use the output power / total efficiency = the output power of the motor or the input power of the system

then calculate the angular speed of the motor shaft, and use the average speed of your weight to convert it to the motor shaft through the transmission ratio
then, the output torque can be obtained by dividing the output power of the motor by the angular velocity

with the power and torque values, you can check the motor samples. But we should know that this algorithm is based on the uniform motion of the mechanical system, and does not consider the acceleration problem of starting. So for the sake of safety, you can give a safety factor for both power and torque, and amplify it by 1.2 times

finally, the matching of inertia is not very important for low-speed system. Don't make a big difference. The sample of the motor will also tell you the allowable load inertia range of the motor. Just choose according to its requirements

I don't know if what I said is clear. I often choose motors, asynchronous, AC / DC servo and step-by-step. This idea should have no problem with your things.

4. T=9550*P/n，
T是力矩，N.m
P功率，kW;
n转速，rpm.

5. You should want to know the inertia of the load. There is such a formula, but your data is too little to calculate. According to the moment of inertia theorem, the torsion moment M = J β
where: j-moment of inertia, β— Angular acceleration

when the cylindrical load rotates around its axis, the moment of inertia J = Mr ^ 2 / 2
where m is the mass of the cylinder, R is the radius of the cylinder

according to △ T seconds to △ T seconds ω The angular acceleration of the cylinder can be calculated according to the requirement of rotational / minute angular velocity β= △ ω/ In this way, according to the radius r, length L and material density ρ， Calculate the mass m and the moment of inertia J,
calculate the angular acceleration according to the required starting speed β， Then the torsion moment M can be calculated. Then select the motor according to M. At the same time, the driving power of the motor can be calculated according to the load speed and transmission ratio
at the same time, you should also consider that the torque obtained at this time is the load torque, and the actual torque of the motor after deceleration, and the rated parameters of the motor have this data.

6. The motor output is torque
if you need to know the force acting on the tangent of a disk with radius r, just divide the torque by R

the power, mechanical efficiency and power factor of the motor should also be known in the calculation process

if mechanical efficiency and power factor are not considered and the motor power is set to P, then there are:
the "torque" of the motor, and the unit is n & # 8226; M (nm)

the formula is t = 9549 * P / n

P is the rated (output) power of the motor, and the unit is kW.
denominator is the rated speed, and the unit is R / min.
P and N can be found directly from the motor nameplate
n here is 100-200 rpm

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