Belleville Washers

X-Mozilla-Keys:

Paul,

I like it, as long as the thrust  loaded direction

will be working with the

belleville spring direction.  It will permit the

thermal expansion

of the main housing without lousing up the

preload.  It's elegant.

The issue is exactly how to find the right

washer(s).  It might

require going to a spring maker and having some

made.


You made one comment recently about beville

washers that I think

is incorrect.  I believe that stacking them in

opposition retains the

same spring constant as a single washer, but gains

the travel equal

to the total number stacked.  Of course, stacking

then nested

adds the spring constants and keeps the same

travel.


Bill Freeman

Two identicle springs of any kind in series results
in half
the spring rate of each spring.

In other words for a given overall deflection each
spring moves
half as far hence half the rate. Another example; A
coil spring
which is really a bunch of torsion bars wound up in
a circle.
Add  coils and the rate  goes down.

Paul Lamar

I have used bellvilles in numerous aerspace applications and they are
quite effective for high loads in compact spaces. Bill's comment about
stacking
arragements is completly right and combinations can give you a wide
variety load/displacement conditions
without going to "specials" - Vance


OK how else can I put this? 

Let's say each spring is 1000 pounds per inch.

I deflect one spring .05 inch and get 50 pounds.
If I deflect it .025 inch I get 25 pounds.

So now I have two spring back to back. I deflect the stack .05 inches.
One spring is deflected .025 and provides 25 pounds. The next spring
now has a force on it of 25 pounds as well and it deflects .025
inches. Total applied force is 25 pounds and total deflection is .050
inches
so the spring rate for the stack  is half or 500 pounds per inch.

Paul Lamar
 
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