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Revolutionary new Clutchless gearbox claim to reduce shift time to none

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Revolutionary new Clutchless gearbox claim to reduce shift time to none

Old 02-20-04, 03:22 PM
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Revolutionary new Clutchless gearbox claim to reduce shift time to none

ZeroShift Ltd: New gearbox shifts in zero milliseconds and blitzes road test
London, July 16 -- ZeroShift Ltd, a UK company, has successfully road tested its radical new shift technology. The time of a gearshift is the period during which drive is interrupted while the next ratio is selected. In the case of ZeroShift(TM), that period is ZERO time. A ZeroShift(TM) gearbox (patents pending) provides an uninterrupted shift, the fastest possible gearshift.

By way of comparison, the dual clutch transmission (DCT) recently released in the Audi TT V6 is no quicker than a good driver using a conventional manual. The same can be said of the BMW SMG, the F1 system in the Ferrari 360 and the Aston Martin Vanquish automated manual transmission (AMT). A car fitted with ZeroShift will convincingly out-accelerate any otherwise identical vehicle - smoothly.

Even current F1 cars take around 60 milliseconds (0.06 secs) for a complete shift sequence that involves an (audible) engine power cut. F1 fans will appreciate that this is a long time to lose on every shift.

ZeroShift Ltd is so confident of the new technology (recently road tested in a TVR Cerbera 4.5) that the company plans to fit a standard 225bhp Audi TT with the system and race it against the new TT V6 DSG (DCT) in front of the media to prove the point. The automotive media has praised the Audi DSG gearbox as the future of transmissions. Watch this space!

ZeroShift represents a radically different engineering approach. Where AMT adds weight and complexity around the gearbox and DCT adds weight and complexity inside the gearbox, ZeroShift addresses the switching of ratios more fundamentally. In simple terms, ZeroShift components replace synchromesh components. AMT and DCT transmissions are merely complex ways of operating 80-year-old synchromesh.

ZeroShift Technical Director Bill Martin says: 'AMT and DCT are just faster steam trains - as a consequence, they are heavier and more expensive to make and maintain.'

On the road, according to the ZeroShift team, the performance is 'amazing'. ZeroShift spokesman Phil James describes it: 'What you get is acceleration, acceleration, acceleration through the gears. That's instead of acceleration, declutch, yaw, acceleration, declutch... in a conventional manual; or acceleration, slur, acceleration... in an auto.

'The difference in performance and feel is very noticeable with the TVR Cerbera where, with the conventional gearbox, the violent acceleration through the low gears really emphasises the yaw of de-clutching between first and second gear accelerations. With ZeroShift, the car just keeps accelerating - it's pretty addictive! You lose no momentum or sense of thrust through the gear-changes. Two ZeroShift gear-changes between standstill and 100mph are worth more than a second.'

A standard Cerbera 4.5 has been timed at 8.4 secs to 100mph, so McLaren F1 drivers should not be complacent if they see a chrome ZeroShift badge on the car beside them at the lights. To wring the best 0-100 time from the F1 needs deft gear-changing skills - the ZeroShift driver will have optimum shifts, every shift. This will be the badge to look out for!

ZeroShift is about much more than going faster, though. The performance advantage is a factor of the efficiency of the system that provides other benefits too, including emissions reduction, lower fuel consumption and smoothness. Bill Martin: 'Emissions and fuel consumption are spiked by conventional gear-changes because the off-then-on action on the accelerator pedal momentarily enriches the fuel mix. ZeroShift does not need the off-and-on gas action. The smoothness issue is one of the ZeroShift system's strongest suits. Shifts are imperceptible, other than noticing change in engine note.'

ZeroShift is able to modify existing transmissions for rapid introduction to the market. But a gearbox developed to fully exploit the ZeroShift system would be considerably smaller and lighter than whatever gearbox it is designed to replace.

Unlike other 'revolutionary' gearbox concepts, a ZeroShift transmission is based on a donor manual gearbox, albeit with extensive internal modifications. No changes to the clutch or bell housing are required. As a consequence, a ZeroShift gearbox can fit straight into a car. Furthermore, ZeroShift can be operated by a conventional stick shift, by column-mounted paddles, or it can be fully automated to work like a conventional automatic. The development car is using its standard H-gate stick shift.

Phil James: 'ZeroShift is smooth for luxury cars, fast for supercars (including motorsport) and economical for minis. With the same engineering element at its core, only the shift strategy changes to suit the application. We think you will see a variety of new supercars offered with ZeroShift from as early as 2005.
Racecar Engineering

A little something that may interest you guys.
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Old 02-20-04, 05:46 PM
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I want!!!
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Old 02-21-04, 05:59 PM
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Yeah but it doesn't discuss at all what it actually does. How it actually accomplishes the shift. I would like to know how it does this, as well as life of the transmission. I would think this would cause harder engaging and thus reduce the life of the tranny and the clutch, as well as being hard on the rest of the drivetrain.

- Steiner
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Old 02-21-04, 07:14 PM
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It sounds like another version of what has been used in Pro Stock cars and the like for years, the difference being the Pro Stock setup is arranged for upshift-only.

Imagine a standard dog-ring gearbox (which is just a standard synchro box with dog sets instead of synchros/teeth) The trick is, you make the sliders (the pieces that slide to engage the dogs on the gear, and transmit power to the shaft) TWO-piece and spring loaded. When you're under load in gear, and you shift into Neutral, half of the slider goes into Neutral, the other half is still driving the gear you were in, because the dogs have slight bevels on them to hold them in place under load. But the spring is now trying hard to pull it back into Neutral.

You put it into the next gear. For a SPLIT SECOND, two gears are engaged at once. Then the previous gear unloads, since it's a different ratio, and the springs yank its half of the slider into Neutral. Voila, no-lift clutchless upshift.

If the dogs weren't designed for upshift-only, the same principle would work for downshifting, although the lack of rev matching would unsettle the drive tires just like if you dumped the clutch on a non-rev-matched downshift in a normal trans. I would imagine that without the heavily acceleration-biased gears, you would want WIDE spacing to give the disengaging half of the slider plenty of time to snap into Neutral, before it hangs up on the next dog and the tranny goes "sprack".

We're talling like 20-30 year old stuff here....
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Old 02-21-04, 08:32 PM
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may its the new CVT stuff....like what they use in Toyota Prius, and some Honda Civic.
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Old 02-21-04, 09:47 PM
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Or the design i came up with a while ago on here - much more efficient and should be able to hold more torque/Bhp than those pitiful chain-driven things by Toyota and Honda!!!
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Old 02-21-04, 10:03 PM
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GM had something like that in the 30's, except instead of a cone, it used a toroid to drive the "ball". It was called the Toric, as I recall.

HP doesn't hurt transmissions, torque does. And "those chain driven things" (actually it's a steel belt) handle a *lot* more power than any other CVT short of a torque converter, which is really a fluidic CVT in and of itself.

However, the original story for this post has nothing at all to do with CVTs....
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Old 02-22-04, 07:43 PM
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but then again, its interesting - so we may as well have two topics!!

I read the chain can only cope with around 60Bhp from one company - so thats where i got that idea from about it being weak

But what Reza mentiond has some scope in this argument, it could be based on the CVT concept
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Old 02-22-04, 08:15 PM
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No, it can't. Read the text - it's simply altering the synchronizers of an existing gearbox.
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