Modeling of Compression Spring exposed to cyclic loading

Hello,

Currently I have a problem of designing a compression spring exposed to
cyclic loading in SolidWorks.

The said spring is pre-compressed and placed in a housing. Then a
cyclic force is applied along the vertical axis of the spring. My
problem is to find in what pattern the spring gets compressed. Do you
please let me know how I could design this system ? (I have already
designed the spring with edges cut and placed in the housing. But I
dont know how to compress the spring into the housing and then later
give it a cyclic load !)

I very much appreciate your kind help and direction.

Sincerely
-Raju

 

If all you are doing is testing the spring, there are mathematical
formulae that can predict failure based upon # of cycles, amount of
compression, ect. There is also software that automates the process of
doing the math so you can test lots of design/material changes in the time
it would take to run it through a std analysis pkg.

If you are trying to simulate motion, there are some things that can be
done in the assembly simulation, but I don't see how to cycle stuff other
than putting the playback in a loop. If you want to get real complex, you
can drive the dimensions of your spring with equations, and a little VBA to
force it to cycle.

Someone's site ( maybe Ed's? ) has an equation driven spring sample.

 

Ed's site appears to be down. I'd also be interested in seeing this
example if someone can host it.

-Matt

 

I'm kind of curious if I am the Ed you are referring to.
I had posted on a few springs to a personal site about a year and a
half ago, but I let that site lapse (lacked the time to do anything
with it. Now that its cold I might actually do something with it).

The springs were not accurate for engineering testing. I would also
recommend the formula or to put your spring vendor to work for you in
developing the apporpriate spring for the job.
But the files were a useable springboard for animations and for
interference detection.
If you want those files, email me at work (the email I use for google
groups has also lapsed)

EdEaton
At
DimonteGroup
Com

 

Velu,

I am not quite sure how SolidWorks can expose a spring to cyclic
loading. If by your question you mean how is a spring set up for
analysis of fatigue and stress evaluation in CosmosWorks I will respond
by saying that this is not the best way to solve the problem. In the
words of one of my professors, "It is driving thumbtacks with a sledge
hammer." Spring manufacturing associations have software that will do
this type of analysis quickly and much more accurately than CosmosWorks
can do. Your spring manufacturer will usually have this software and
will check your design anyway. This is a case where even a textbook
solution is superior to doing FEA.

If you are simply asking how to represent the spring in a model in both
compressed and uncompressed states then I would search the newsgroup
because this has been discussed many times.


TOP

 

You're probably remembering the various examples of springs on Mike Wilson's
site:
http://www.mikejwilson.com/solidworks/solidworks_files.htm

Jerry Steiger
Tripod Data Systems
"take the garbage out, dear"