Torsional Spring Force Transfer

  • #1
I'm trying to work out the force transfer along a torsional spring. Using Hooke's law, the opposing force from applying a force to the torsional spring can be calculated using

[tex]\textbf{F} = -\textit{K}\vartheta[/tex]

with theta representing the angular deflection from its equilibrium position and K the spring constant. Using the diagram below I can work out the forces and deflection if I applied a force at the green dots but I can't find a formula anywhere for calculating the force transferred along the beam that I would apply at the red dots. The top part of the digram represents one torsional spring, and the bottom is what I'm trying to do. I assume the formula would be something like

[tex]\textbf{F} = [/tex] Force applied / [tex]\textit{K}[/tex] / Distance (length of the beam)

Any help would be much appreciated

forcetransfer.jpg
 

Answers and Replies

  • #2
tiny-tim
Science Advisor
Homework Helper
25,836
251
Hi Zach! :smile:

Sorry, I'm not understanding the question …

transfer of force from where to where?

and a torsional spring stays where it is, and your picture seems to be showing something else. :confused:

Force should be the same all the way along a spring , just as tension is the same all the way along a ("massless") string. :smile:
 
  • #3
Hi Tim!

Thanks for replying. What I'm trying to do is simulate the real time flexing of a group of metal tubes (chassis). For processing reasons I can't go into metallurgy algorithms so I'm treating each chassis tube member as a torsional spring. If I had 2 chassis tubes rigidly connected to each other such as in the bottom part of the diagram, and I applied an upward force at the green dot, that tube would bend like a torsion spring and apply a counter force downward depending on the spring rate and deflection. What I'm trying to work out is if those 2 tubes are connected to each other, there would be a moment created at the middle red dot. How would the spring rate effect that moment? I hope that helps you understand what I'm trying to achieve
 
  • #4
Redbelly98
Staff Emeritus
Science Advisor
Homework Helper
Insights Author
12,133
160
I too am trying to understand what is being asked, but I don't.

It seems that all forces and torques could be calculated without invoking spring constants, since the sums of forces and torques should be zero ... or am I missing something? Are forces being applied at each of the 3 dots? Is the deflection small compared to the length of the tubes?
 

Related Threads on Torsional Spring Force Transfer

Replies
1
Views
962
Replies
6
Views
3K
Replies
3
Views
1K
Replies
2
Views
6K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
2
Views
920
  • Last Post
Replies
1
Views
5K
  • Last Post
Replies
3
Views
5K
  • Last Post
Replies
3
Views
2K
Top