Bi stable belleville spring design
Bi stable belleville spring design
(OP)
There was a great thread a while back about this, and I was looking for some more help. I understand to get the bi stable effect i need a h/t of 2.82 or greater. I need a combined travel of .025" and am constrained to a diameter of .096. I need about 50 Grams of force at the top, and have about 150 grams of actuation force available. If I get the same travel up and down, then the h=.0125 and t= about .0046 I should get the bi stable action, What materials will put me in the range I need?
thanks for the help
Bryan
thanks for the help
Bryan





RE: Bi stable belleville spring design
http://www.bellevillesprings.com/belleville-washer...
RE: Bi stable belleville spring design
This will have an influence on the h/t you need.
You are asking for a travel between both stable positions of 0.025" which is also influence the h/t greatly.
Adding all this and the very small OD of the spring you will need h/t so high and the thickness of spring to be very very small resulting in very very high stresses in the range of thousands of ksi (1 ksi = 1000 psi).
RE: Bi stable belleville spring design
I have about 150 grams of Driving force, I would like something close to 50 grams of holding force on one side. There is very little force needed in opposite position. The travel I need is .025" between stable positions. I have room to move on the 50 grams at the top 25 to 50? I kind of pulled the 50 out of the air. The critical design piece is the Travel, and force to drive from one side to the other. I am working on .01" centers but I could do layers if I need to to get more OD. the shape is another variable that I could work with, How does notching the inside and outside change the equations? (see attachment)
I really thank you for your help with this.
Bryan
RE: Bi stable belleville spring design
I have know knowledge of any design formulation literature that deals with such springs as compared to the vast literature regarding belleville springs. Basically, those springs are three times more flexible than bellevile springs however, there is the issue of stresses too. The point I wanted to present in the previous post was that to my best experience and the theory of belleville springs you are climbing on a very high tree and you are in an charted area as long as the space for the belleville spring is so limited for the 0.025" travel no matter the forces.