×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Motor in-lb torque converting to actual weight?
3

Motor in-lb torque converting to actual weight?

Motor in-lb torque converting to actual weight?

(OP)
I'm trying to figure out what size stepping motor I will need to push a piston at 500 Lbs of pressure. The motors I was looking at tell me a in-lb torque rating, but I need to be able to figure a good size to start with. I will be gearing this down as well.
But if a motor is rated at say 260 in-lbs. torque, and is geared 1 to 1 what pressure would that be able to push? I think I will be able to figure the gearing once I know this. Thanks for you help....

RE: Motor in-lb torque converting to actual weight?

2
do an internet search for a .pdf document called "Smart Motion Cheat Sheet"

TygerDawg

RE: Motor in-lb torque converting to actual weight?

If you are in a frictionless world........

260 in-lb is the torque required to pull 260 lb on a 1" raduis.  So if you had a 2" OD pulley you could pull 260 lb.  With a 4" OD pulley, 2" radius, you could pull 130 lb.

The size motor you will need will also depend on how fast you want to move.  One horsepower equation is:

(speed in feet per min.) x (force in lbs.) / 33,000

(60 fpm ) x (260 lb) / 33,000 = .47 hp

Of course we live in a world with friction so the gearing or mechanism you use to convert the motion of motor to the desired motion will use up some of your power.  As a rule of thumb an acme screw will use up about 50% of you power.

If you give some more details it would help.

Barry1961

RE: Motor in-lb torque converting to actual weight?

(OP)
Thanks for the info. So with a motor rated at 260in-lb. torque, if I had a 1" gear(I guess the teeth count matters?)on the motor shaft directly connected to a 4" gear, would that multiply the torque 4 times (not counting friction)to 1040 lbs.? Or is it not that simple? Thanks in advance

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources