×
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

# Compound Gear

 Forum Search FAQs Links MVPs

## Compound Gear

(OP)
How much is the maximum RPM that have been ever achieved by the using of sequence of compound gears.

### RE: Compound Gear

Depends on the size. I would suspect that for a set of smaller gears, the speeds could be quite high.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

### RE: Compound Gear

Drive mechanisms for centrifugal superchargers (automotive applications) can have very high output speeds.

The centrifugal supercharger on a Kawasaki H2 motorcycle drives the supercharger at 9.2 times crankshaft speed, and max crankshaft speed is 13,000 rpm, so supercharger rpm would be 120,000 rpm under those conditions. The final output stage is a planetary-geared speed increaser with an 8:1 speed ratio.

### RE: Compound Gear

I have a hand held mini-grinder that has a 40k rpm motor and ~130k rpm output.
The guys that built it said that they tested one with ~250k rpm output, but it too bulky and ran hot.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

### RE: Compound Gear

Speeds achieved in the real world are directly and inversely related to size of the gears, as others have stated.

You'll also find that if you do the math, the speed is directly limited by contact velocities. There's an upper limit based on gear material.

#### 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!

Close Box

# Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

• Talk To Other Members
• Notification Of Responses To Questions
• Favorite Forums One Click Access
• Keyword Search Of All Posts, And More...

Register now while it's still free!

Already a member? Close this window and log in.