2 Speed Gearbox

Open for any sort of non-technical discussion regarding EVs
User avatar
EV2Go
Senior Member
Posts: 2059
Joined: Wed, 16 Jul 2008, 00:21
Real Name: Paul
Location: Brisbane 1963

2 Speed Gearbox

Post by EV2Go » Thu, 26 Mar 2009, 00:26

Andrew funny you should say put the diff and simple gearbox together, because I was thinking that very same thing last night. A cast alloy housing with a 2 speed gearbox incorporated would be just the ticket. Compact design, oil all in one place, no clutch, cable gear select...

mikedufty
Senior Member
Posts: 632
Joined: Tue, 02 Dec 2008, 00:15
Real Name: Michael Dufty
Location: Perth, Western Australia
Contact:

2 Speed Gearbox

Post by mikedufty » Thu, 26 Mar 2009, 01:41

My subaru ICE has a two speed gear box between the main 5 speed and the wheels (it is dual range). Would such a dual range transfer case be useful for electric vehicles? The subaru ones can be shifted while driving, unlike some bigger 4WD that require you to stop. The liberty is only about 10% reduction, which might not be enough to be useful, I think the older models, brumby etc had a bigger reduction.

User avatar
Electrocycle
Senior Member
Posts: 985
Joined: Sun, 19 Oct 2008, 20:23
Real Name: Andrew
Location: Sydney
MSN: dumhed@dumhed.com
Contact:

2 Speed Gearbox

Post by Electrocycle » Thu, 26 Mar 2009, 01:43

each car uses a different diff though, while the gearbox could be the same.

I think there's a point where the extra efficiency is outweighed by the project being too specific, making it hard to be commercially viable.
The Engine Whisperer - fixer of things

User avatar
Johny
Senior Member
Posts: 3729
Joined: Mon, 23 Jun 2008, 16:26
Real Name: John Wright
Location: Melbourne
Contact:

2 Speed Gearbox

Post by Johny » Thu, 26 Mar 2009, 04:46

I agree on not including with the diff. Most likely it would be for an independent rear end which would rule out us solid rear end folk.

I reckon just a 2:1 and 1:1 would do it as most motors would be Ok to 4000 RPM which would be max. required speed for 1:1.

If possible, two pre-ordered ratios would make it cope with everyone's requirements. If not, maybe two or three choices?

User avatar
EV2Go
Senior Member
Posts: 2059
Joined: Wed, 16 Jul 2008, 00:21
Real Name: Paul
Location: Brisbane 1963

2 Speed Gearbox

Post by EV2Go » Thu, 26 Mar 2009, 15:48

I drifted off onto a more adhoc approach there for a sec, but if we are talking a commercial consumption, then yes a limited gear ratio options would be necessary to work with different diff ratios.

It wouldn’t necessarily have to be done completely from scratch, if the right gears could be sourced from an existing deployment, it would cut costs. That would be the preferred option since it is one less part you need to manufacture.
Last edited by EV2Go on Thu, 26 Mar 2009, 04:50, edited 1 time in total.

Mark T
Groupie
Posts: 252
Joined: Fri, 04 Jan 2008, 03:56
Real Name: Mark Taylor
Location: Sydney

2 Speed Gearbox

Post by Mark T » Thu, 26 Mar 2009, 16:00

We have a member here in Sydney who works for a company that designs and builds gearboxes. It may be worth having a chat with him at the next meeting.

User avatar
EV2Go
Senior Member
Posts: 2059
Joined: Wed, 16 Jul 2008, 00:21
Real Name: Paul
Location: Brisbane 1963

2 Speed Gearbox

Post by EV2Go » Thu, 26 Mar 2009, 16:02

um yeah, that would definately be a worth while contact.

User avatar
stuartri
Groupie
Posts: 67
Joined: Fri, 02 Nov 2007, 05:32
Real Name: Stuart Richards
Location: Australia

2 Speed Gearbox

Post by stuartri » Sun, 29 Mar 2009, 23:40

Thanks for your reply Taffy.

There is a lot of information on youtube on the device. It is manufactured by fallbrook technologies. Very easy to setup. I am incorporating it into me new design which I am hopful to run at the EVChallenge this year. Missed last year as started a new job and could not attend.

I have attached a picture of the unit. Still need to fit the disk brake.


Regards StuartImageImage

AMPrentice
Senior Member
Posts: 401
Joined: Tue, 05 Aug 2008, 19:30
Location: down south

2 Speed Gearbox

Post by AMPrentice » Tue, 31 Mar 2009, 20:10

mikedufty wrote: My subaru ICE has a two speed gear box between the main 5 speed and the wheels (it is dual range). Would such a dual range transfer case be useful for electric vehicles? The subaru ones can be shifted while driving, unlike some bigger 4WD that require you to stop. The liberty is only about 10% reduction, which might not be enough to be useful, I think the older models, brumby etc had a bigger reduction.


this kind of transfer box I never knew existed it would be ideal to study if it works as you say it does. There are many of subarus at wreckers and can you tell us the model?

Maybe it could provide a base for a 2 speed?

http://www.zeitgeistmovie.com/

No Queen, No Prime Minister, No hierarchical system to break down our communities
Never vote Labour, Liberal or Maggots like them.

User avatar
Richo
Senior Member
Posts: 3737
Joined: Mon, 16 Jun 2008, 00:19
Real Name: Richard
Location: Perth, WA

2 Speed Gearbox

Post by Richo » Tue, 31 Mar 2009, 20:56

stuartri wrote:
It is manufactured by fallbrook technologies. Very easy to setup. I am incorporating it into me new design which I am hopful to run at the EVChallenge this year.


Very nice for a bicycle but not for a car.
If you look at thier website they have torque and RPM limitations which make it unsuitable for a car.
Also they say it has "Automotive" applications but is still vapourware.
They say for LEV upto 5kW.
Don't really need a CVT on my lawnmower...

Also please note that although it may be a CVT they don't specify the efficiency.
My concern is that what you make up by keeping optimum motor power you will loose in efficiency through the CVT.
As for the eVchallenege you would need to test the efficiency to see if it is worth while.
Otherwise you could be better off with a single gear, bigger motor and more caps.
esp with a $1200 price restriction...
So the short answer is NO but the long answer is YES.
Help prevent road rage - get outta my way!

User avatar
Electrocycle
Senior Member
Posts: 985
Joined: Sun, 19 Oct 2008, 20:23
Real Name: Andrew
Location: Sydney
MSN: dumhed@dumhed.com
Contact:

2 Speed Gearbox

Post by Electrocycle » Tue, 31 Mar 2009, 23:54

the Subaru transfer case is built into the main gearbox if I remember correctly.
There's just an extra selector lever going into the gearbox.
The Engine Whisperer - fixer of things

User avatar
stuartri
Groupie
Posts: 67
Joined: Fri, 02 Nov 2007, 05:32
Real Name: Stuart Richards
Location: Australia

2 Speed Gearbox

Post by stuartri » Wed, 01 Apr 2009, 01:17

Thanks for your reply Richo.

In respect of your comments for the EVChallenge I would agree with you regarding a fixed sprocket arrangement as we won the 2007 challenge on exactly that configuration. Our record still stands.

My motivation for the unit is more for a general commuter than a purpose built EV Challenge racer.

I will be able to comment on performance when I get it integrated as I have a development agreement for the unit.

PS it would be one great lawnmower though lol

Regards Stuart

User avatar
Richo
Senior Member
Posts: 3737
Joined: Mon, 16 Jun 2008, 00:19
Real Name: Richard
Location: Perth, WA

2 Speed Gearbox

Post by Richo » Wed, 01 Apr 2009, 17:19

You need a development agreement to use it?
I'd be interested in efficiency tests.
In comparison to the hub gears rohloff & shimano types it is about half the price.
So the short answer is NO but the long answer is YES.
Help prevent road rage - get outta my way!

moemoke
Groupie
Posts: 115
Joined: Tue, 20 May 2008, 04:47
Real Name: Andrew Pugsley
Location: Moe, Victoria,

2 Speed Gearbox

Post by moemoke » Wed, 01 Apr 2009, 17:58

This topic seems to be splitting in two!
I think the Subaru transfer box is part of the gearbox and they are used
in all 4wd manual models from the 70's uptill now (I think)
Suzuki lj80- Sierra had a seperate hi/lo transfer box (as do most older 4wd's) but I'm not sure the ratios would be suitable for using as a gearbox and whether they could handle the power without going through a gearbox first also some transfer boxes can only change gears with the vehicle stationary. what bout using an old 3 speed Holden/Ford/Valiant gearbox, atleast you'll have reverse which can come in handy.
We do not inherit the Earth from our Ancestors,
we borrow it from our Children.

fuzzy-hair-man
Groupie
Posts: 118
Joined: Wed, 12 Nov 2008, 16:40
Location: Canberra

2 Speed Gearbox

Post by fuzzy-hair-man » Wed, 01 Apr 2009, 19:01

Electrocycle wrote: each car uses a different diff though, while the gearbox could be the same.

I think there's a point where the extra efficiency is outweighed by the project being too specific, making it hard to be commercially viable.


I was inclined to agree but then I though that Azure's gearbox is a gearbox / diff combined (all be it with a single ratio) and evidently they make it sell??? If you had something like the planetary where you could select one of 3 ratios even if you couldn't change gears it would be a pretty useful product I'd think?

OK so this is probably specific to front wheel drives and Azure have the American market to sell into, and we don't want to leave the rwd guys out in the cold but for a front wheel drive taking drive from the motor into a 2/3 speed box which has prop shaft like inputs and outputs and then onto a diff is all using up precious space, so I think unless the gearbox mates flush up to the motor or is integrated into the diff it's not really going to work space wise for front wheel drives. Image

Edit: changed could to couldn't in: 3 ratios even if you could change gears...
Last edited by fuzzy-hair-man on Wed, 01 Apr 2009, 08:43, edited 1 time in total.

User avatar
EV2Go
Senior Member
Posts: 2059
Joined: Wed, 16 Jul 2008, 00:21
Real Name: Paul
Location: Brisbane 1963

2 Speed Gearbox

Post by EV2Go » Wed, 01 Apr 2009, 19:35

Not quite what I had in mind, but this might come in handy for anyone wanting to step up or down their gearing / change drive direction http://www.tolomatic.com/products/produ ... gear-boxes

That is the simplistic design I am talking about. If we could keep that level of simplicity and just add another changeable gear it would be perfect.

Image
Last edited by EV2Go on Wed, 01 Apr 2009, 08:37, edited 1 time in total.

User avatar
Richo
Senior Member
Posts: 3737
Joined: Mon, 16 Jun 2008, 00:19
Real Name: Richard
Location: Perth, WA

2 Speed Gearbox

Post by Richo » Wed, 01 Apr 2009, 21:09

moemoke wrote: This topic seems to be splitting in two!
agreed.
I started the following thread for discussion of the smaller CVT's here:

viewtopic.php?t=1068
So the short answer is NO but the long answer is YES.
Help prevent road rage - get outta my way!

fuzzy-hair-man
Groupie
Posts: 118
Joined: Wed, 12 Nov 2008, 16:40
Location: Canberra

2 Speed Gearbox

Post by fuzzy-hair-man » Wed, 01 Apr 2009, 21:45

EV2Go wrote: Not quite what I had in mind, but this might come in handy for anyone wanting to step up or down their gearing / change drive direction http://www.tolomatic.com/products/produ ... gear-boxes

That is the simplistic design I am talking about. If we could keep that level of simplicity and just add another changeable gear it would be perfect.
Going off the graphs in the full catalog here (10.4Mb) these gearboxes aren't able to cope with revs over 1200 rpm so they might be a bit small, the peak torque it can deal with seems to be 2500 inch lbs = ~282Nm

at least that's what I get from the graph below:

Image

User avatar
EV2Go
Senior Member
Posts: 2059
Joined: Wed, 16 Jul 2008, 00:21
Real Name: Paul
Location: Brisbane 1963

2 Speed Gearbox

Post by EV2Go » Wed, 01 Apr 2009, 22:06

As I said not “exactly” what I was looking for, more along the lines of what would be ideal in concept. Have a look at the guts of it, how much simpler could you get?

On the home page you will note they custom build. You could provide them the specs you need it to be to meet the motor requirements and have them make a batch of them.

Image

gttool
Groupie
Posts: 79
Joined: Mon, 26 May 2008, 01:46
Real Name: Geoff OToole
Location: sydney
Contact:

2 Speed Gearbox

Post by gttool » Wed, 01 Apr 2009, 22:27

Yes I have looked at building a 2 speed gearbox for when i do the bike conversion looked at using both a planetary configuration or coventional gear train
for the bike i was going to use a cone clutch possibly ,on the bike as an example using the clutch lever as a gear change it would be normally in the high gear, pulling on the clutch would disengage the clutch and low range would be selected ,sounds simple enough hopefully find enough time to build a sample

after testing of that would follow on with a larger 9" version

I could machine the small gearbox from billet no problems would Be inclined to cast the larger box

Geoff

fuzzy-hair-man
Groupie
Posts: 118
Joined: Wed, 12 Nov 2008, 16:40
Location: Canberra

2 Speed Gearbox

Post by fuzzy-hair-man » Wed, 01 Apr 2009, 22:31

Oh sorry I wasn't dissing it they look quite cool and useful I just went looking for more info and if they would take the torque and RPM required and just posting back what I found, they do look a neater and smaller way of making drives do 90 degree bends than belts or chains. Image

User avatar
Taffy
Groupie
Posts: 238
Joined: Mon, 23 Jun 2008, 15:12
Real Name: Taffy Flynn
Location: Melbourne
Contact:

2 Speed Gearbox

Post by Taffy » Mon, 20 Apr 2009, 00:00

Just seeing if anyone has made any more progress?

The best looking CVT i found was the nissan tordial CVT, they are stacked end to end to give you other gearing options
http://www.carbibles.com/transmission_bible_pg2.html

Gemini
Noobie
Posts: 24
Joined: Sat, 28 Jun 2008, 08:25

2 Speed Gearbox

Post by Gemini » Mon, 20 Apr 2009, 06:46

Ive just been watching video's of CVT's and am amazed. Engineering is amazing!

AMPrentice
Senior Member
Posts: 401
Joined: Tue, 05 Aug 2008, 19:30
Location: down south

2 Speed Gearbox

Post by AMPrentice » Mon, 20 Apr 2009, 18:38

some kind of cvt has to be the way or......

a box like say the mitsubishi lancer which are virtually indestructible and have small form factor.

It needs to be a box that is able to lose 3 of the gears and synchros and allow the use of say only 3rd (2 to 1) and 4nd (1 to 1) and reverse.
Last edited by AMPrentice on Thu, 23 Apr 2009, 11:36, edited 1 time in total.
http://www.zeitgeistmovie.com/

No Queen, No Prime Minister, No hierarchical system to break down our communities
Never vote Labour, Liberal or Maggots like them.

Gemini
Noobie
Posts: 24
Joined: Sat, 28 Jun 2008, 08:25

2 Speed Gearbox

Post by Gemini » Sat, 25 Apr 2009, 21:40

How about one of these CVTs ?

http://www.youtube.com/watch?v=R8AzqtomwD0

Post Reply