Auto clutch ready to go
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• Automatic clutches for manual gearboxes came a step closer last week when Fichte] & Sachs revealed that its ECS system is ready for mass production. ECS replaces the clutch pedal and linkage with an electronic package which takes over the operation of a standard F&S clutch.
The German clutch specialist has worked with MAN on the system, which has been exhibited on an MAN (CM 24-30 August 1989). It is said to be compatible with MercedesBenz's [PS electronic gear shift, and either MAN or Mercedes-Benz is expected to be the first truck manufacturer to specify it — both buy their clutches from F&S.
With ECS the gearlever is retained but a network of electronic sensors operate the clutch via an electrically powered mechanism bolted to the bell housing.
The main sensor, in the gearlever, detects pressure from the driver's hand. Signals from it, and from other sensors monitoring engine and road speed and throttle demand, are fed to a central computer which monitors the system's condition 125 times every second.
When the driver starts to move the lever the computer checks that the other signals concur before signalling the power unit (similar to a windscreen wiper motor) to disengage the clutch. The clutch is engaged once the shift is complete.
ECS-equipped vehicles can stop in any gear: the enginespeed sensor will disengage the clutch whenever tickover is reached. Holding the gear lever in position keeps the clutch disengaged. The system relies on a minimum 6V/10W power supply to work the clutch of a 12-volt system, so vehicles with completely flat batteries cannot be tow started.
ECS will not function if its power supply falls below 7.5V and vehicles may be fitted with "limp-home" clutch pedals.
F&S says that the system's advantages include advanced safety, reduced wear and improved fuel economy. ECS will carry a price premium. F&S will not quote figures but says that van users might pay as much as they would for a powered sunroof or "a good radio-cassette".
It is unclear how the driver licensing authorities will view