spring in deformable parts

[tchan2]

I know how to do a simple spring, 1 helix, as deformable part. How do I do a spring with grind ends in defomavle part?

 

[mmauldin]

Check out his thread for some examples:

http://eng-tips.com/viewthread.cfm?qid=324342

 

[JohnRBaker]

Attached is a simple assembly which should answer your questions. When you open the Assembly make sure that the Load Option 'Partial Loading' is toggled OFF. Once the assembly is open, go to the Part Navigator and expand the 'User Expressions' item and then change the value of 'Height' to something between 8" and 14".

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
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[tchan2]

John, Thanks for the reply, the assembly helps but not quite answer my question. I'm trying to use the same spring in different application with different installed height. I created a spring using tube feature with a join curves formed by 3 helical curves. 1st & last helix with a pitch same as the wire diameter & one turn only. The middle helix has a pitch equals to ((spring_length-2*wire_dia)/no of turn). Then I trim the top & bottom ends with datum planes. My problem is on the last helix, I don't know how to get the location of helix associate with the 2nd helix. When I change the spring length in the assembly, the join curve operation fails because the last helix eill stay where it was & not touching the 2nd helix. I hope I explain it better this time.

 

[JohnRBaker]

This will all be much simpler once you've installed NX 8.0, which will be released soon. We have completely reimplemented the helix function which will now allow you to control not only the diameter and length/no of loops of a helix, but also the pitch at anywhere along the length of the helix itself.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

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

 

[jnikolauk]

I solved that priblem by making the length of all the helixes the a function of the overall length minus the end grinds. for a spring with two end turns with ground ends would something like:
pitch = (overall length-((2*wire diameter)+(2*end grind)))/active coils

formula may differ depending how you set up your end grinds.

 

[jnikolauk]

that's one end turn per side

 

[tchan2]

Thanks everybody for the help, I got the law define spline works now.

 

[JohnRBaker]

This will all be much simpler once you've installed NX 8.0, which will be released soon.

Sorry, I meant NX 8.5.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

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