On or around Tue, 20 Jul 2004 23:55:16 +0100, "Paul S. Brown"
<
[email protected]> enlightened us thusly:
>Steve Taylor wrote:
>
>> Austin Shackles wrote:
>>> On or around Tue, 20 Jul 2004 14:50:44 +0100, "Badger"
>>> <[email protected]> enlightened us
>>> thusly:
>>>
>>>
>>>>even worse than the old 4 speed auto in the mini / austin
>>>>1100/1300!
>>>
>>>
>>> Oi. me dad worked on the design team of that one. One thing you can say
>>> is that they were ahead of the times in putting 4 gears in it.
>>
>> Yes, BUT they are supposed to stay IN the box. Not automatically deposit
>> them on the road.....
>>
>
>Two words.
>
>Hillman Electromatic.
>
>
>The damn thing used iron filings and an electromagnet instead of a viscous
>torque convertor.
>
>Now imagine *any* moisture getting in there.
Austin had an interesting CVT ages ago as well. I dunno if I can describe
it in words or by ascii-art, but I remember seeing an article about it in
classic cars ages ago, someone had restored about the only one left in
existence.
OK...
Imagine a flat plate like a lathe surface plate only thicker. Imagine a
second one, facing the first. The first is the driving plate and the second
is the driven plate. Now imagine that you cut a circular groove around each
plate, such that the section of the groove is most of a semicircle. The
outer edge of the groove is near the outside diameter of the plate, the
inner edge is not far from the centre. Now put the 2 plates together,
facing eachother, so that the 2 grooves (one on each plate) both co-incide
with the same hypothetical circle.
The drive was transmitted from one to the other by a set of wheels, arranged
on a carrier in between the 2 plates. The wheels are capable of being
tilted so that they can align from the inner edge of the driving plate to
the outer edge of the driven plate, around to where they align the opposite
way 'round. thus, 1:1 is in the "middle", and it gears down on the one side
and up on the other. suitable choice of final drive ratio achieves the
right overall ratios.
I imagine the problems this device suffered were mainly due to slip. the
wheels could have clutch-style lining around their periphery (and may have
had, for all I know).
and now, I hand you over to the people trying to sell 'em:
http://www.torotrak.com/howitworks.html
http://www.torotrak.com/variator.html
although they seem to be using two.
the second link has moving pictures...
http://www.torotrak.com/media/virtualdrive.swf
interesting site. If they can get the traction fluid sorted, they've solved
the problems of mechanical contact and wear.
--
Austin Shackles.
www.ddol-las.fsnet.co.uk my opinions are just that
If all be true that I do think, There are five reasons we should drink;
Good wine, a friend, or being dry, Or lest we should be by and by;
Or any other reason why. - Henry Aldrich (1647 - 1710)