Hobbyist Forums banner
  • If you've ever been interested in the history of Zee Toys or Maisto over the course of the 80s, 90s and into the modern day, you should come over to the Hobbytalk Ask Me Anything with Chepp going live on Tuesday, September 21st and running until Thursday, September 23rd. Don't miss out! You can ask your questions here!
1 - 1 of 1 Posts

1 Posts
Discussion Starter · #1 ·
Hey guys, I'm currently making a variable speed manufacturing conveyor belt for my mechanical engineering senior design project. I am lacking in my electrical skills, but I figured out the theoretical requirements needed to run the system and was hoping someone could help out with figuring out how to choose a motor/speed reducer. The requirements are as follows:

Motor Type: Brushless
Torque Range: 10.5-11.2 Nm = 94-99in.-lbs.
Motor Speed Range: 2-13 RPM
Power Range: 2.2-152.4 W = 0.0029-0.205 HP
Temp Range: 50-110 F = 10-45 C
It will be run continuously in a humid environment. There are no restrictions to size or whether it's AC or DC, but if it's AC then 120V is preferred.

I realize that motor will not have those exact specs so I was not sure how to choose it. I've tried Googling a few things and so far came up with these pointers:

1) Given a constant load (i.e. torque) the speed of a motor is solely dependent on the voltage applied to the motor.
2) Power is the product of speed and torque. The maximum power of a DC motor is produced at the operating point that is defined by operation at half the no-load speed and half the stall torque.
3) The general rule of thumb for operation of a DC micromotor is to operate the motor at approximately 70% to 90% of its no-load speed and from 10% to 30% of its stall torque.
4) For use with gearing, the motor should be selected for the minimum speed practical by choosing a motor with higher voltage ratings than the available voltage supply.
5) For DC motors operated at a constant voltage, the speed and torque produced are inversely related. The higher the torque produced, the lower the speed of the motor will be.

However, I am not sure where to go from here. Hopefully someone can help!
1 - 1 of 1 Posts