biella-manovella-bilanciere

[MaxiPT]

the problem is this (see picture attached for the scheme):
I have to calculate the angle of oscillation (osc) of the balancer according to the positions (fulcrum crank and x-y balancer) and to the various lengths that may have biella, crank and bilinciere.
I am not interested in speed and effort that naturally vary in the range of parameters, I am only interested in simply being able to calculate the maximum oscillation of the balance sheet according to the complete rotation of the handle.

Thank you.

 

[MFT]

with autocad, pull the trajectories of the pins and see the oscillation.

Mar

 

[reggio]

hi as already suggested by marco, I would trace the rays
lmanovella
lbilance
Ibiella

positions the horizontal lmanovella at "9 o'clock" which is the closest point to the other lightning and then find the oscillation looking at the intersection of the rays,
repeat by placing the horizontal lmanovella at "hour 3" which is the farthest point to the other lightning :d

 

[Fulvio Romano]

schematizing in autocad is the fastest thing. the minimum and maximum points are those in which biella and crank are overlapped.
but it is neither accurate nor immediate. to know when biella and crank overlapping to make some subsequent graphic approximations.

If you need something more precise than this "attempt" procedure, take a look at the quadrilateral theory, especially the grashof quadrilaterals.

is a well-studied problem in literature

 

[Fulvio Romano]

perhaps towards the end of this document:
http://members.xoom.virgilio.it/pellif/dispense-mdm/lez7.pdffind something interesting, but I have not read carefully. ancient remembrances of robot mechanics... if I found the notes.. .

 

[listastudio]

if you are interested in a graphical spreadsheet mark you graphiclc in http://www.atnet.it/lista/grcalc.htm

 

[zeigs]

I would do like this:
- lbil radius circle with center in the fulcrum of the barbell
- radius circle l biella+l manov with fulcrum in the crank
- radius circle l biella-l manov always with fulcrum in the crank
- two passing lines for the fulcrum of the barbell and the intersections between the barbell circle and the other two
- I mix the ancle between the two segments

you should get the exact size very simply

Hi.

 

[GiGa]

If I have not understood badly, the maximum and minimum angle points are when biella and crank are aligned (maximum and minimal length of leverage).
at that point of meeting with a triangle of which you know practically everything or almost (considering that the longest side will be given by the sum of biella+manovella and biella-manovella).
a sheet of excel with a couple of trigonometry formulas should not be complicated.
otherwise, to use the graphic method, use the constraints of autocad 2010 that to do these studies is fine. . .

 

[MaxiPT]

First of all thank you very much to all for the answers.
I have to say that I've exposed the problem a little bit badly, even because I didn't know where to start with the first evidence.
I've already arranged in fact to bind everything in autocad 2010 (as giga says) and I have to say that it works great or better, you see, turning the crank, the actual biella-bilanciere movement and so I can check if "works".
I realized that my starting variable is the oscillation angle of the balancer that must be of a certain precise value (92 degrees approximately).

So I solved the problem with the graphic construction suggested by zeigs but backwards and that's
- lbil radius circle with center in the fulcrum of the barbell
- two rays in the ch circles form the angle of oscillation I want.
- ipotizzo l biella e l manov
- radius circle l biella+l manov on the first straight
- radius circle l biella-l manov on the second straight
- if there are intersections between the two circles the system works by indicating the two points where the crank fulcrum resides.
thank you very much zeigs and thank you all anyway.