how brakes work
Thread Starter
Launching!
Joined: Dec 2005
Posts: 237
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how brakes work perhaps this would be the better place to put this thread up... anyway. i understand how calipers and pads and such work... but how do the pads seperate from the rotor? pads are free floating within the caliper housing/chatter plates, and the pistons push the pad aginst the rotor, but the pads aernt connected to the caliper/piston, so when the brake is let off, the piston seperates.. but how is the pad taken with it? it seems like when dealing with high forces/frictions like those in brakes, pad seperation would be important
The pads are always touching/wiping the surface of the rotor even with zero pressure in the brake lines. With no pressure being applied to the master cylinder, no pressure is applied to the slave cylinders/calipers and the coefficient of friction from the pad to the rotor is extremely low. Drum brakes have return springs that actually pull the brake shoes back away from the inside of the drum.
Is this the sort of explanation that you are looking for?
Steve
Is this the sort of explanation that you are looking for?
Steve
they generate clearance through wheel speed also. the same way main bearings pull in oil once the crank starts spinning, the pads and rotor pull a small amount of air between them. its also comaprable to how the hard drive in your computer "lifts" the read/write head off the surface. as the disk drive(rortor) spins, the heads(pads) lift off the surface, creating clearance. its all bernoulli's principle.
Last edited by slowpoke96z28; Jan 25, 2006 at 09:05 PM.
TECH Resident
Joined: Dec 2004
Posts: 881
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I believe you will find it is a function of runout. Which is why a very flat disc will have better actuation...the pad has less distance to move. These forces are high enough to move the whole caliper in frame for the floating caliper systems on F-bodies and Y-bodies other than the C6Z. Fixed calipers have pistons on both sides and just retract the pads.
Thread Starter
Launching!
Joined: Dec 2005
Posts: 237
Likes: 1
good points, the idea that the pads and rotors create lift between eachother and seperate is really cool. i suppose the coefficent of friction between an unpreassurised line would be really really small too.. so even if they dont seperate it would be negligable.
