Re: Analysis of Dual Pivot Brake


As a followup, we can look at the relative pad movement. Let x1 be
the movement of the left pad, x2 the movement of the right pad. For
small movements, the vertical movement of the contact point of the
two arms is

dy = dx1*L5/L2 = -dx2*L6/L4.

The (negative) ratio is

-dx1/dx2 = L4*L5/L2/L6.

Expressed in terms of k we get

-dx1/dx2 = L4/L2*k/(1-k)

Ideally we'd like this ratio to be 1, so that both pads open equally.
Solving for k we get

k = L2/(L2+L4)

Plugging that into the gain ratio and simplifying we get

F/T = 1/2*(L1/L2 + L3/L4)

So, with k set so the pads move equally, the gain of
the brake is the average of the gain of the two
lever arms without the connection (the connection is required
for operation.


--
Joe Riel
.

Relevant Pages

  • Re: Analysis of Dual Pivot Brake
    ... the movement of the left pad, x2 the movement of the right pad. ... Ideally we'd like this ratio to be 1, so that both pads open equally. ... Plugging that into the gain ratio and simplifying we get ... lever arms without the connection (the connection is required ...
    (rec.bicycles.tech)
  • Re: Analysis of Dual Pivot Brake
    ... the movement of the left pad, x2 the movement of the right pad. ... Ideally we'd like this ratio to be 1, so that both pads open equally. ... lever arms without the connection (the connection is required ...
    (rec.bicycles.tech)
  • Re: Analysis of Dual Pivot Brake
    ... the movement of the left pad, x2 the movement of the right pad. ... Ideally we'd like this ratio to be 1, so that both pads open equally. ... lever arms without the connection (the connection is required ...
    (rec.bicycles.tech)
  • Re: Analysis of Dual Pivot Brake
    ... the movement of the left pad, x2 the movement of the right pad. ... Ideally we'd like this ratio to be 1, so that both pads open equally. ... lever arms without the connection (the connection is required ...
    (rec.bicycles.tech)
  • Re: Design for a small tube/valve mixer
    ... even knows what output levels it'll be required to deliver. ... a preamp circuit with a single fixed gain will not perform very well. ... You can get 20dB of *free* gain from the input transformer of course, but with a 0dBu input, even with the pad in place there is 0dBu on the grid of the first valve which in itself would be an issue for an ECC83 biased at a volt or less. ... I wouldn't expect an inline pad to have a significant or fatal effect on phantom power except in very rare cases, if the correct pad topology is used, or am I missing something? ...
    (rec.audio.tubes)