Torsion spring movement in assembly
I saw the video of how to construct a compression spring that will provide movement in assemblies, very helpful. Does anyone know how to make a torsion spring work in an assembly? As it is wound, the OD of the spring will need to get smaller in size. Thank you in advance,
Jeff
Ben 12:59 pm on May 3, 2010 Permalink
Hummm this is a good challenge… Not really an answer per-se but something I just played with:
So there is some formula work to deal with here. What we need to determine is what the diamter (radius) change is in relation to the degrees of change in torsion.
I have made a spring using a sweep funtcion (http://www.youtube.com/watch?v=8X0JMtx4ZIs)
Now the radius is 2.5″ and the spring is 1080 degrees rotation so I made an assumption that for every degree added to the 1080 it will compress the 2.5″ to 2.4″ or 0.1″ (just an example) . So the fromula we put into the dimension for the radius is the number of degrees times a constant to get us the ratio. I am for simplicy going to use 0.002 as the contstant.
Click on tools-equations, then double click the model and choose the radius dimension and click the add button on the equation dialog. then click on the degrees of rotation and multiply it by 0.002 to get the equation:”D1@Sketch1″ = “D1@Sweep1″*.002
Now if you change the rotational degrees of the spring the diameter will change too.
Note: if you try and double click on the degree dimension it will not let you edit it but if you single click on it, it will…
Now all of this is really rough but hopefully it will give you something to work with or try.
Attachment – 2010_5_3_13_58
Ben 1:04 pm on May 3, 2010 Permalink
Grrrr the constant I have increases the radius but I hope that gives you an idea of how to use the formulas to get this effect. I am not sure how to animate it though… but it is a start.