Nx gear feature 5

[tadej001]

Hello everyone...

I'm trying to make a parametrized feature of a gear.
If someone have a tutorial or eaven a sample of how to do it, I would be greateful.

Regards,
Tadej

 

[JohnRBaker]

No, but I have (attached to this reply) an NX Open program which will create a spur gear for you.

John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.

 

[tadej001]

Ok...thanks...
But this is to simple for me....I need a gear with corection and other details...

but thank you for the NX open programme...it is useful to see how thinks works.

Thank you,
Tadej

 

[doc1955]

Here is a basic gear I did a long time back it is done in sketcher I've used it and modified it several times.
It is real basic.

Doc

http://www.goodrich.com

 

[DavidTolsma]

Grab a machinery's handbook and Knowledge Fusion.

-Dave Tolsma

http://Tolsnet.com/jobs

http://groups.google.com/group/NX_CAX/

http://groups.google.com/group/plm-exchange/

 

[mudler]

I also did a gear wheel long time ago, mab be it will be usefull. The expression list is in danish, but M is the module and Tandantal is number of teeth.

-regards Lars

 

[crazydiamond]

Lars,

Very interesting approach to creating a gear tooth profile. One question though, why the offset curves (features #10 & 11).

Thanks in advance for your reply.

Ron
Design Analyst

 

[speedster29]

Here is a fully parametric AGMA spur gear part I created. The expressions are labeled; you can modify the pitch, number of teeth, pressure angle, and tooth thickness and the gear will regenerate. No warranty expressed or implied...

 

[hudson888]

Well done Speedster!

He did it in NX-5 for those one earlier releases.

This is the sort of thing I had been wanting for some time even though I'm not tuned into whether AGMA is the best or most common standard. Many of the gears we worked with are either SAE or Metric standard and the trouble is always that if you want to calculate and repoduce the involute geometry correctly then you've an uphill battle. One of the main problems is that access to information about the geometric detail of the involute form seems to be restricted to those willing to pay the standards orgainizations for their documetation.

I was therefore impressed to see how you had defined the involute and wondered if you would allow me to be ignorant enough to ask whether it is accurate or not?

I realise there are other examples available that do a passable job of putting teeth on a diameter but providing a correct involute tooth form that maintains a good contact angle is a different matter yet one highly to be desired given that we're using a high end CAD system to define such a common engineering mechanism.

Cheers

Hudson

 

[speedster29]

I'm glad you liked it. The involute curve is mathematically accurate. I got the equations from a Pro/E tutorial document I found on the web. It was fairly easy to adapt it to NX. When I first created the model I compared the tooth profile with one generated using Mastercam, and the profiles were identical.

http://www.cadquest.com/books/pdf/gears.pdf

The calculations for tooth width, depth, dedendum, etc. are based on AGMA standards. My job involves gearbox design with plastic molded gears, and AGMA standards work fine most of the time.

The involute equations are the same for metric or english gears, so with a bit of work my model could be converted to create a metric gear.

 

[evdesigner]

Hey Speedster,

I was wondering if you had any ideas about the part not updating correctly if I try making the gear larger than 1 inch. (say, 35 dp and 52 teeth). Do you get errors also?

 

[SDETERS]

I had an Excel Spreedsheet that spits out a x y and z function. This is made for I-Deas Function splines not NX. I do not know how simliar Function Splines in I-Deas is versus the Law curves in NX?

 

[hudson888]

I have seen something similar an excel spreadsheet that spits out a DXF file. It is not however superior in my opinion to the gear that speedster29 above created.

Best Regards

Hudson

www.jamb.com.au

Nil Desperandum illegitimi non carborundum

 

[SDETERS]

This one just creates the true Involute curve for you. Then you have to rotate and mirror and such to get your gear teeth with correct tooth thicknesses. We also make custom PM gears so this method lets us get our root done how we want it. We also use this create true involute ansi splines. We have wire cut many gears and splines using this geometry and it works great for us.

 

[tsjaikdus]

I've used this (non-NX) tutorial for a spur gear. It took me some days to finish it, though.

http://gtrebaol.free.fr/index.html