Use of Expressions to constrain gears in assembly environment

[Pattanshetti]

I am using nx 7.5 and i wanted to constrain 2 gears in assembly environment. I read one post on using Expression Tool. Am not getting how exactly to use this. Please help me in this regard.Thank You.

 

[JohnRBaker]

I suspect that the comment about using expressions with gears was not so much to 'constrain' them as it was to create a relationship so that when one gear was rotated that the other would rotate the proper amount as if they were constrained. The way you do this is to constrain both gears using an 'Angle' constraint, each of which will then have an expression controlling the angle-of-rotaion. Now you simply consider one of the 'gears' to be the 'driver' and you then relate, using the gear ratio, the angle of first gear to the second.

Attached is an example of a pair of gears that I've used the 'Animation' function to create a relationship between the two gears using expressions. After extracting the files, open the assembly file and then go to...

Menu -> View -> Visualization -> Create Animation...

...and when the dialog opens push the button labeled 'Preview Animation' and when the next dialog opens you'll see what essentially are VCR like controls. Push the 'Play' button to see the animation sequence of the gears.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
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To an Engineer, the glass is twice as big as it needs to be.

 

[Pattanshetti]

Thank you