| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 2088.1 | Constant Velocity What? | BAHTAT::CARTER_A | Andy Carter..Morph the Borg | Mon May 24 1993 14:52 | 2 |
| What does the T stand for?
|
| 2088.2 | | MUGGER::LEACH | There's a hole in my fuel pipe... | Mon May 24 1993 15:06 | 3 |
| >> What does the T stand for?
Transmission ?
|
| 2088.3 | | WAYOUT::WAYOUT::LOAT | Ahead groove factor 5! Yeah! | Mon May 24 1993 16:24 | 10 |
| 2088.4 | Sorry, I've just realised - "bandwagon". Sorry, Sorry | PEKING::SMITHRW | The Great Pyramid of Bloke | Mon May 24 1993 17:03 | 11 |
| 2088.5 | It's worth a few compromises! | UTROP1::BOSMAN_P | | Mon May 24 1993 17:33 | 20 |
| Not just the mini's either!
- Fiat Uno and Tipo 1.5, called Selecta
- Ford Fiesta
- Volvo 440/460 1.8i (90bhp)
Btw Subaru actualy offers it on the 1.3 4WD Justy!
I liked this tranny so much that I took the Volvo in the deal.
Six weeks in a 1.5 Uno Selecta got me hooked and a month in an Astra
had me appreciate the 440.
Given the fact that it's transport I wanted, I have the wife's Fiero
and two motorbikes for fun, the choice has realy paid off. The
thoroughly practical and roomy 5-door 440 with it's smooth 1.8 injected
Renault engine matched to the incompaireble CVT makes me actualy relax
when commuting! Even trafic jams are taken in it's stride.
Do yourself a favour and try the CVT concept in a Fiesta, Uno or
whatever even if just for the fun of it.
Peter
|
| 2088.6 | C.V. at it's best! | UTROP1::BOSMAN_P | | Mon May 24 1993 17:42 | 7 |
| Oh, I forgot.....I regularly pull a trailer with the two motorbikes or
a caravan and usually have 350 lbs of live dog meat in the back when
travelling this way. The CVT excells! Smooth and completely hassle
free. Since it comes with a standard oil-cooler the extra load doesn't
get it(the 440) sweating either.
Peter
|
| 2088.7 | | UPROAR::EVANSG | Gwyn Evans @ IME - Open DECtrade -> DTN 769-8108 | Mon May 24 1993 18:00 | 7 |
| Didn't Top Gear do a piece of it not too long ago, where they took
a number of members of the public and had them test drive a few small
cars fitted with CVT, without first telling the that it wasn't a
standard auto transmission?
IIRC, they were all inpressed with it and a couple were very keen
to ensure that their next cars had it...
|
| 2088.8 | The proof of the pudding.... | UTROP1::BOSMAN_P | | Mon May 24 1993 19:19 | 4 |
| Yep. And these were 35-45 hp cars with the previous generation CVT!
Even the ones not keen on automatics decided this was the way to go.
Peter
|
| 2088.9 | Is it HP limited or Torque? | CMOTEC::POWELL | Nostalgia isn't what it used to be, is it? | Tue May 25 1993 16:28 | 9 |
| 2088.10 | HP allright. | UTROP1::BOSMAN_P | | Wed May 26 1993 11:05 | 11 |
| Malcolm,
Taking the principle in view I think it is actually HP since the torque
is determained by the gearing of the input shaft. As Hp devided by rpm
results in torque the diesels give the same loading on the CVT.
The variation of the pulleys is the same for a given hp, no matter what
the revs and thus torque. It's the differential- and input-shaft
gearing that determain the highest and lowest ratio. The CVT takes care
of a constant variation between these.
Peter
|
| 2088.11 | How's it work then? | BAHTAT::CARTER_A | Andy Carter..Morph the Borg | Thu May 27 1993 15:12 | 8 |
| re .3
Yep, silly me ! I was thinking of those universal joint things that go
to the steerable wheels of a FWD car.
(Although isn't the idea of CVT that the engine does a constant speed?)
Anbody know a technical description of how CVT works?
|
| 2088.12 | Constant smoothness! | UTROP1::BOSMAN_P | | Fri May 28 1993 16:27 | 31 |
| CVT basicly works like this:
The principle:
A band of a fixed length runs over two axles, transmitting drive from
the one to the other and vice versa. Variation of the drive ratio is
created by enlarging the diameter of the one axles exactly as much as
simultanuously decreasing the diameter of the other and thus keeping
band length constant.
The max. possible variation in ratio is limited by the constructional
limits on the min. and max. diameter of the axles.
The construction:
A high-tech chain built from space tech. metal rings forms a flexible
but VERY stretch resistant band.
This band runs within two drums. The band/drum construction is such
that drive can be applied in two directions.
The whole mechanism runs in oil and is hydraulicly operated.
The governing:
The governing mechanisme uses, engine revs, road speed, inlet vacuum,
throttle position and several related functions as input to determain
the optimum revs/gearing ratio.
Result:
Engine speed remains constant under light loads. Differing loads ask
for differing engine speeds and thus the speed settles again.
Peter
|
| 2088.13 | | PEKING::SMITHRW | The Great Pyramid of Bloke | Fri May 28 1993 16:50 | 8 |
| I never quite understood how a metal band running on the smooth faces
of metal cones could actually transmit any power at all. I could cope
with the old rubber band having enough grip, but the current glorified
expanding watch bracelet has me foxed - has it got rubber facings or
the like?
Richard
|
| 2088.14 | Instant pulling power!!! | UTROP1::BOSMAN_P | | Fri Jun 25 1993 16:04 | 13 |
| No rubber. Just high-tech, in fact nuclear reactor tube, material.
Precision engineering and manufacturing with incredible tolerances
enables a very close "conical fit". You know, the type that made the
fly-wheel of your moped stick to the crankshaft.
A very trick shackle shape takes care of the rest.
Meanwhile I'v doen 5K miles and are even more enthusiastic. On a trip
to the Yorkshire moors with two motorbikes on a trailer I realy got to
appreciate the optimum availebillity of torque. Hairpins,
unexpected stops, pull-oofs, starts and whatever on 1:5 climbs were
taken in the stride. Just aim and squeeze!
Peter
|
| 2088.15 | | PEKING::SMITHRW | Off-duty Rab C Nesbit stunt double | Fri Jun 25 1993 18:07 | 18 |
| Nuclear reactor tube material? You mean maraging (sp?) steels? Oh.
8*)
You mean it wrings and un-wrings whatever many times a second? Wow!
Techy!
I didn't have a moped, it was a BSA 197cc in a 350 RE frame. And no
force in the universe could induce the flywheel to stick to the crank
in anything other than the most casual fashion... I became an expert in
field re-times - haul out the plug/screwdriver in to detect TDC/line up
the Tippex (sorry Snopake in those days) marks.... I have faith in
Science, but only belief in engineering.....
Logic compels me to buy another BX: I only wish I could get one with
CVT.
Richard
|