What makes one electric motor last longer than another?

Question

I am making a science project and the device needs to run for a very very long time without wearing out. How can you tell which electric motors last longer? Are there industrial motors that will last longer than hobby type electric motors? Are "stepper" motors long lasting? Also, how do you determine what size motor is needed for a specific task?

For this device it will only move a fraction of an inch ... but it will need to lift something that is fairly heavy.. a couple ounces maybe.. straight up on a track-like construct... over and over for a long long period of time.. years -- or as long as possible.

Answer 1

The best advice I can give you is to obtain a motor that is much stronger and more powerful than you actually need - this will assure that it isn't straining at the bit every time it's cycled.
A stepper motor or a regular motor both can be extremely dependable if they're not pushed to their limit and overheated.
Most motors will have a rating plate - compare this to what you determine you need - and multiply that by five or ten and you should be in good shape. Simply put, the motor will be operating at 10 or 20% of its rated capacity - and it will easily do this for a long, long time.
Good luck.

Answer 2

Motors usually fail due to brush wear, bearing failure, or overheating. A brushless motor will take care of the first problem; proper rating will handle the other two. For the bearings, use a good quality ball-bearing motor and be careful about any side loading or bending load on the shaft. For best wear, mount the motor rigidly and use a compliant coupling. To avoid burnout, make sure the motor is rated for continuous duty and that you have adequate air flow around it. You will need to calculate how much torque your project requires and size the motor and coupling accordingly. You'll probably also want your motor to survive your mechanism getting stuck. If the motor doesn't include overload protection, protect it with a slow-blowing fuse. A slip clutch could add another level of protection.

Answer 3

I would agree with the brushless motor. An induction motor is also good. Look at motors that use ball bearings as a the support system. Typically BLDC motors and steppers with have these. Abuse will shorten motor life.
Also depends on what you are willing to spend. For a science project...why would you want it to last upto a few years??

Answer 4

Overloading causes overheating which causes motor death. Overloading itself (causing "locked rotor" condition or slipping) will kill a motor.
The more "industrial" a motor is, the more likely it is to have thermal and overload protection

"Cool" thing about a stepper, though is you can slow down the rate at which it steps, if you have a controller to do that (as opposed to just running it off ac) Do as much calculation as you can stand. Choose a bigger motor than you need. Slow down the stepping if it seems like its getting overloaded. This all assumes you don't need a specific speed.

Answer 5

A brushless DC motor might be a good choice. However, if you are just moving a couple ounces a fraction of an inch, you might look at a solenoid or voice coil.