Pedersen self energizing brakes.

Every day is an adventure for a new bike mechanic. There seems to be n
end to the exotic componentry out there.
I just had a unit come in with the Pedersen cantis. It was easy enoug
to figure out how they work, the only real mystery is, well, why? I a
certainly no engineer,so maybe someone who is can explain the advantag
if there is one. How does moving the pads forward as the brake arm
rotate toward rim contact energize the brake?
Was this just another answer to a question no one asked

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Dan Burkhar