There have been many interesting emergency brake designs over the years.
If you had an early 60's Chrysler product, you would find a drum brake
at the end of the transmission attached to the driveshaft used as the
emergeny brake.
I had a car with one and it was quite capable of locking up the rear
brakes while the car was in motion.

Todd
'88 Westy

David Brodbeck wrote:

>On Tue, 26 Nov 2002, Simon Reinhardt wrote:
>
>
>
>>Interesting. What cars is this on? I helped my neighbor do the brakes
>>on his Lexus, and the rear discs had drums AS THEIR CENTER SECTION!!!
>>It was weird! And hideously efficient. The drum parts were about as
>>large as the rear drums on an A1/A2 VW.
>>
>>
>
>Yeah, I've heard of this design too.  My Honda has 4-wheel disc brakes,
>but instead of using the center of the rear disc as a drum they made the
>handbrake mechanically engage the rear pads.  This is the only emergency
>brake I've ever seen that actually works well enough to deserve the name.
>The car WILL NOT MOVE with it on.  Any other car I've owned you could
>drive off wih the brake set, though sometimes only with difficulty.  One
>Ford Aerostar I drove had an emergency brake that would only grab well in
>the forward direction, so you had to be careful when parked facing uphill.
>
>BTW, total brake system failure *can* happen even in dual-circuit designs.
>A guy I knew had an El Camino lose all braking ability quite suddenly due
>to a bad master cylinder.  Don't know the details of what went wrong in
>that case.
>
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