Handbrake /parking brake not emergency brake and DCT.

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Handbrake /parking brake not emergency brake and DCT.

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Peter Pick-Up and I got a little off topic on a stop-start battery thread so I thought I'd pick it up here.

Last post by Peter was:
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Originally Posted by g8rpi
Dual clutch transmissions are an exception as there is no torque converter. You are effectively in gear with both clutches out. However you are still blinding the driver behind you with the brake lights. You still should have the parking brake on though. Just because most people don't do it does not mean they are right.


Rubbish.
In D, during standstill there's always one clutchplate engaged, hence the "creeping" behavior.
Again there is no such thing as a "parking brake", (or maybe the Croma has..??)
It is an emergency brake, that's why Mercedes has a foot operated emergency brake, as a lot of USA cars have this foot operated device as well.
Theory is you can apply more force by foot during an emergency stop when the normal brakesystem fails...
The emergency brake is cable operated by law, so not depending on hydraulics, which can leak..."

Peter obviously has no idea how a DCT works. It's two conventional (not planetary + torque converter like a classic automatic transmission) gearboxes in paralell, both engaged and the dual clutch transfers the engine input to the required one and then changes the other to the next anticipated ratio ready for transfer. If the clutch was engaged when stationary it would be slipping and quickly burn out. When you liftt off the brake at standstill the ECU engages the clutch. Yes I've owned a DCT equipped car (Dodge Journey A.K.A Fiat Freemont) and driven many different automatics including my wife's car.
It is a Parking brake, even in California "Every motor vehicle shall be equipped with a service brake system and every motor vehicle, other than a motorcycle, shall be equipped with a parking brake system." see https://law.justia.com/codes/california/2005/veh/26450-26458.5.html
The Croma handbook calls it a Handbrake (hand operated parking brake)
Handbrke-croma.jpg
As do Alfa manuals. The Stelvio is electric and the manual calls it an Electric Parking Brake.

Robert G8RPI.
 
In the UK, the position is quite clear. You should normally apply the parking brake whenever the vehicle is stationary, unless the wait is likely to be very short.

This article, written by an approved driving instructor, basically says it all.
 
<SNIP>
I wasn't aware that the Reliant Robin was available with an automatic gearbox...

Well I once took the engine and automatic gearbox out of a Reliant and put them in an old electric milk float to turn it into a drag racer. It won the race against a modified electric float
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MM-&-ME.jpg

Robert G8RPI
 
Don't see how it could ever ebe called an emergency brake?
You pull it unable emergency all your really achieve is spinning into another car or a wall
It's basically designed to stop thec car from moving and not for slowing it down when


Then what would you call in a car with a electric system as many won't activate when the car is moving


Anyway when what the last time you heard about a car totally loosing all braking?
 
Strangely enough my old uno had a seal disintegrate in the master cylinder they worked on the initial test drive but then the pedal slowly went to the floor on a long hill..thankfully it is possible to slowly stop a car with the handbrake. The trick is not to yank it on and turn hard like you want to handbrake turn.
 
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