# [EVDL] How to drive hundreds of miles a day in an ev.



## EVDL List (Jul 27, 2007)

Only 100 miles in a day. How about 1056 miles in 24 hours which is a 
average of 44 mph. This was done at the time, to show that a EV can be 
driven 1000 miles in a day. You will have to have a time machine to go 
back to 1975 to see this done with a proto type EV call Transformer I by the 
EFP Co. in Troy, Mich.

After this EV accomplished this feat, with only one replacement of a 25 amp 
diode, I received this vehicle for further research, modifications and 
upgrades. I still am running it today. It use a 900 amp CableForm 
PulseMatic Triac motor controller and a 180 volt 300 AH cobalt cells that 
can be charge to 252 volts using a 200 amp charger that was either develop 
from a 3 phase bank of 50 KVA transmission connected in 250 VAC Delta or 
from a motor-generator unit that provided 37.5 kw 3 phase 250 VAC delta that 
had a output of 280 DC from a 3 phase bridge that has eighteen 300 amp 
diodes in it. This pusher was only normally use to either transport the EV 
about 500 miles, or can be use as a emergency power plant for your home.

Top speed of the EV was 92 mph at about 1 hour driving, but kept the speed 
lower so the EV could average about 44 mph with 30 to 40 charging stops. 
Did not have to charge the batteries clean to 100 percent SOC and did not 
discharge too many times below 40% SOC.

First thing I did when I received this EV in Montana, is to drive it as is, 
which was mostly in a breadboard stage of wiring and installation, was take 
it to a vehicle testing place, to check up the HP, torque, wheel rpm, motor 
rpm, per motor and battery ampere results.

Did the first full one time discharge test drive around the city on a river 
road drive until I discharge the batteries to 1.100 SG which was 79 miles at 
speeds from several stops up to 60 mph.

At 79 miles, the EV was going very slowly and was only 1000 feet from my 
home, so I stop the EV and let it set for about 15 minutes, to let the 
negative plates, diffuse more of the acid into the electrolyte. Was able to 
drive it all the way home. I never again drop the batteries below 50% SOC 
again.

Roland







----- Original Message ----- 
From: "Lawrence Rhodes" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>; "SFEVA" 
<[email protected]>
Cc: "Zappylist" <[email protected]>
Sent: Saturday, July 05, 2008 8:39 AM
Subject: [EVDL] How to drive hundreds of miles a day in an ev.


One interesting possibility is the Vectrix. (maxiscooter) It can go 40 or so 
miles on the freeway & then charge in two hours & go another 40 miles all on 
house current.(typical household plug) It might actully make it to LA in a 
couple of days. You could build a car for about 24k but then you would have 
to figure out some way to connect two 50 amp chargers to it at one time. I 
guess you could find campsites with 50 amp service. This is a math exercise. 
Find the places to charge. Find the distances. Build the vehicle. A car with 
two 50 amp chargers could charge in under 2 hours & still have a 40 mile 
useable range. Quick calculation. 400 miles to LA from San Francisco. That 
is ten charges or 20 hours of charging. Plus about 6 to 7 hours of driving. 
You could do it in a day of Le Mans style driving. You could see the sights 
while charging. You might EVen do it a little quicker. A good freeway car 
doesn't use all
that much in the amps department. Your charging time might be only 1 hour. 
It would make for a long day. This is only a rough estimate but if you had a 
vehicle that would cruse the freeway at 100 amps or less then your charging 
and driving time would be the same. One hour of drive for one hour of charge 
remember what makes electric cars impractical is not the range or driving 
time but the charging time. Here is something you can do yourself. Find out 
what vehicle has the lowest current draw on the freeway. (don't forget to 
figure in hills like the little mountain range between Bakersfield & LA) 
Figure out how many chargers you will need to charge in under an hour. Look 
up all the places you can charge on the way. You now have your electric 
superhiway. Use at your own risk. By using electricity you can calculate it 
easily. So if you used two 50 amp chargers & you car drew 100 amps your 
driving and charging times will be the
same. So efficiency becomes important. I bet a Sprint/CRX/Insight 
conversion would do the trick. I know Cedric Lynch could do it. His vehicles 
are extremely efficient. Lawrence Rhodes.....
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## EVDL List (Jul 27, 2007)

Note: The people that uses the Yahoo group that send e-mails to the EVDL, 
please delete the Yahoo address in the the above Cc: and Bcc: or the 
messages become rejected. The message will still be sent to the EVDL but 
will not sent to the other addresses unless that person is a member of that 
group.

Roland


----- Original Message ----- 
From: "Roland Wiench" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>; "Electric 
Vehicle Discussion List" <[email protected]>; "SFEVA" 
<[email protected]>
Cc: "Zappylist" <[email protected]>
Sent: Saturday, July 05, 2008 10:56 AM
Subject: Re: [EVDL] How to drive hundreds of miles a day in an ev.


> Only 100 miles in a day. How about 1056 miles in 24 hours which is a 
> average of 44 mph. This was done at the time, to show that a EV can be 
> driven 1000 miles in a day. You will have to have a time machine to go 
> back to 1975 to see this done with a proto type EV call Transformer I by 
> the EFP Co. in Troy, Mich.
>
> After this EV accomplished this feat, with only one replacement of a 25 
> amp diode, I received this vehicle for further research, modifications and 
> upgrades. I still am running it today. It use a 900 amp CableForm 
> PulseMatic Triac motor controller and a 180 volt 300 AH cobalt cells that 
> can be charge to 252 volts using a 200 amp charger that was either develop 
> from a 3 phase bank of 50 KVA transmission connected in 250 VAC Delta or 
> from a motor-generator unit that provided 37.5 kw 3 phase 250 VAC delta 
> that had a output of 280 DC from a 3 phase bridge that has eighteen 300 
> amp diodes in it. This pusher was only normally use to either transport 
> the EV about 500 miles, or can be use as a emergency power plant for your 
> home.
>
> Top speed of the EV was 92 mph at about 1 hour driving, but kept the speed 
> lower so the EV could average about 44 mph with 30 to 40 charging stops. 
> Did not have to charge the batteries clean to 100 percent SOC and did not 
> discharge too many times below 40% SOC.
>
> First thing I did when I received this EV in Montana, is to drive it as 
> is, which was mostly in a breadboard stage of wiring and installation, was 
> take it to a vehicle testing place, to check up the HP, torque, wheel rpm, 
> motor rpm, per motor and battery ampere results.
>
> Did the first full one time discharge test drive around the city on a 
> river road drive until I discharge the batteries to 1.100 SG which was 79 
> miles at speeds from several stops up to 60 mph.
>
> At 79 miles, the EV was going very slowly and was only 1000 feet from my 
> home, so I stop the EV and let it set for about 15 minutes, to let the 
> negative plates, diffuse more of the acid into the electrolyte. Was able 
> to drive it all the way home. I never again drop the batteries below 50% 
> SOC again.
>
> Roland
>
>
>
>
>
>
>
> ----- Original Message ----- 
> From: "Lawrence Rhodes" <[email protected]>
> To: "Electric Vehicle Discussion List" <[email protected]>; "SFEVA" 
> <[email protected]>
> Cc: "Zappylist" <[email protected]>
> Sent: Saturday, July 05, 2008 8:39 AM
> Subject: [EVDL] How to drive hundreds of miles a day in an ev.
>
>
> One interesting possibility is the Vectrix. (maxiscooter) It can go 40 or 
> so miles on the freeway & then charge in two hours & go another 40 miles 
> all on house current.(typical household plug) It might actully make it to 
> LA in a couple of days. You could build a car for about 24k but then you 
> would have to figure out some way to connect two 50 amp chargers to it at 
> one time. I guess you could find campsites with 50 amp service. This is a 
> math exercise. Find the places to charge. Find the distances. Build the 
> vehicle. A car with two 50 amp chargers could charge in under 2 hours & 
> still have a 40 mile useable range. Quick calculation. 400 miles to LA 
> from San Francisco. That is ten charges or 20 hours of charging. Plus 
> about 6 to 7 hours of driving. You could do it in a day of Le Mans style 
> driving. You could see the sights while charging. You might EVen do it a 
> little quicker. A good freeway car doesn't use all
> that much in the amps department. Your charging time might be only 1 
> hour. It would make for a long day. This is only a rough estimate but if 
> you had a vehicle that would cruse the freeway at 100 amps or less then 
> your charging and driving time would be the same. One hour of drive for 
> one hour of charge remember what makes electric cars impractical is not 
> the range or driving time but the charging time. Here is something you can 
> do yourself. Find out what vehicle has the lowest current draw on the 
> freeway. (don't forget to figure in hills like the little mountain range 
> between Bakersfield & LA) Figure out how many chargers you will need to 
> charge in under an hour. Look up all the places you can charge on the way. 
> You now have your electric superhiway. Use at your own risk. By using 
> electricity you can calculate it easily. So if you used two 50 amp 
> chargers & you car drew 100 amps your driving and charging times will be 
> the
> same. So efficiency becomes important. I bet a Sprint/CRX/Insight 
> conversion would do the trick. I know Cedric Lynch could do it. His 
> vehicles are extremely efficient. Lawrence Rhodes.....
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
> 

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## EVDL List (Jul 27, 2007)

Great website Roland!
Actually the pics are not at "ooh-ooh-one",
but at "zero-zero-one"
See here:
http://go-ev.net/pics/001.html
or see here:
http://go-ev.net/
Regards,
Jay
-------------------------------------------------


> --- Roland Wiench <[email protected]> wrote:
> > Here is the pictures of Transformer I that was
> > modified and customize =
> 
> ...


----------



## EVDL List (Jul 27, 2007)

On Sat, 5 Jul 2008 07:39:58 -0700 (PDT), Lawrence Rhodes


> <[email protected]> wrote:
> 
> >One interesting possibility is the Vectrix.(maxiscooter) =
> 
> ...


----------



## EVDL List (Jul 27, 2007)

G'day All

So now for a new challenge on the theme. I was asked today about the 
potential for a 300km (200-mile) range EV or plug-in hybrid that 
could do at least 150km (100 miles) of electric-only at 110km/h (60mph).

Soooo... first reaction was "expensive!" but then the discussion 
turned to the practicalities.

The person asking the question is a mechanical engineer who sold his 
business early and is just 'dodging along' doing a routine service 
for some industrial gasses people. As part of that he travels to a 
town 200km away at least once per week (high-power [415V 3-phase 32A] 
electricity for charging is available). He can afford it (wether he's 
willing to is another question, but going with the flow for now). The 
vehicle would need to maintain some payload (the service gear) and 
the driver plus one passenger. The basic vehicle would need to be not 
modified as far as the chassis and central body is concerned, for 
simplicity of the motor registry requirements.

So, a pickup truck with as many aero improvements that can be got 
away with. Lithium batteries, almost for sure, but maybe possible to 
get away with lead-acid? AC drive for easy regen as it's hilly for 
half of the 200km trip.

As to the hybrid question, a 3 or 4 cylinder ICE, possibly a euro 
diesel. Not a pusher (sounds like Transport here in Aus finds the 
question 'too hard' so probably not going to be pursued). So either 
set up as a generator, or better to engage the diesel into the drive-train.

So how to mate a 4500RPM diesel up to a 10,000RPM AC drive? He has 
the capability to make/modify a gearbox to adapt the two together, 
and he's happy to just engage the diesel for the 60km/h to 110km/h 
time, and disengage it for stop-and-go traffic.

One thought is a transfer case from a 4WD, with the AC drive on a 
single-ratio box into the normal input of the transfer case. The 
diesel using a conventional clutch driving into the front output of 
the transfer case, and the rear axle driven normally from the rear. 
When he's ready to engage the diesel, start, clutch disengage, 4WD 
lever in, clutch engage and away? Nasty jolt if he doesn't get it 
smooth. A lock-up torque converter on the diesel?

He's due to catch up for a serious talk in a couple of weeks, so any 
ideas that I can run past him are welcome.

TIA

Regards

[Technik] James

PS: petrol has hit $1.90 per litre here (about US$6 per gallon, and 
Diesel is worse)

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## EVDL List (Jul 27, 2007)

You might want to have a look at:
http://www.evalbum.com/122

This is an S10 with an onboard gen set using lead-acid. It HAS been
used to drive hundreds of KMs in a day.

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## EVDL List (Jul 27, 2007)

On Wed, 9 Jul 2008 10:28:14 -0400, "nicolas drouin" <[email protected]>


> wrote:
> 
> >You might want to have a look at:
> >http://www.evalbum.com/122
> ...


----------



## EVDL List (Jul 27, 2007)

> Finally, your website link is broken. If I go directly to
> http://www.vehiculevert.org, all I see is a french language page. 
> Is there an
> English one?


http://www.vehiculevert.org/index.php?lien=2-litres-en


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## EVDL List (Jul 27, 2007)

> Neon John <[email protected]> wrote:
> > On Wed, 9 Jul 2008 10:28:14 -0400, "nicolas drouin" <[email protected]>
> > wrote:
> >
> ...


----------



## EVDL List (Jul 27, 2007)

> you wrote:
> 
> This link has an English translation about his generator:
> 
> ...


----------



## EVDL List (Jul 27, 2007)

Google web page translation tool does a pretty good job.

Jerome
San Antonio, TX



> <[email protected]> wrote:
> 
> > > Finally, your website link is broken. If I go directly to
> > > http://www.vehiculevert.org, all I see is a french language page.
> ...


----------



## EVDL List (Jul 27, 2007)

Also not to be neglected is this truely great project, spear-headed by
Richard at REV Consultants in Ottawa, Ontario:

http://aztext.com/ZCC_photo_montage.cfm

Here he uses a Fisher-Panda genset, as an add-on to the brand-new
miata that he converted in 2000.


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## EVDL List (Jul 27, 2007)

> On 11 Jul 2008 at 13:24, nicolas drouin wrote:
> 
> > Here he uses a Fisher-Panda genset, as an add-on to the brand-new
> > miata that he converted in 2000.
> ...


----------



## EVDL List (Jul 27, 2007)

> On 11 Jul 2008 at 14:58, EVDL Administrator wrote:
> 
> > On 11 Jul 2008 at 13:24, nicolas drouin wrote:
> >
> ...


----------



## EVDL List (Jul 27, 2007)

How much does this Fisher-Panda genset cost?

Regards
Hank
----- Original Message ----- 
From: "EVDL Administrator" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Friday, July 11, 2008 3:42 PM
Subject: Re: [EVDL] How to drive hundreds of miles a day in an ev.




> > On 11 Jul 2008 at 14:58, EVDL Administrator wrote:
> >
> >> On 11 Jul 2008 at 13:24, nicolas drouin wrote:
> >>
> ...


----------



## EVDL List (Jul 27, 2007)

APU's are off topic. The point was how to drive a long way in an ev. Anybody could hook up an apu or tow your ev where you want to go. The elegant solution is to do it with batteries. Lawrence Rhodes

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## EVDL List (Jul 27, 2007)

> James Massey <[email protected]> wrote:
> > At 10:00 PM 8/07/2008, I wrote:
> >>G'day All
> >>
> ...


----------



## EVDL List (Jul 27, 2007)

On Mon, 14 Jul 2008 12:21:38 +0100, "Evan Tuer" <[email protected]> wrote:


>Why not use a sprag clutch instead, and then you can start the diesel
>on the starter as required, either for continuous cruising or just to
>go up hills. When going down hill, or any time you can manage on
>electric alone, switch off the diesel so that it's not slowing you
>down or using fuel.

Same thought here. At first I thought you were using slang for sprag clutch,
James, and then I realized that you meant a transmission-style dog clutch. I
would NOT do that.

It also seems like you've left out one other operating mode - charging the
battery with the diesel. That would be quite important if you couldn't get to
a charging station, assuming the diesel really will be insufficiently powerful
to climb hills.

The easiest way to do that is with a SEPEX motor. That gives you easy regen
and charging capabilities. This wouldn't be as sophisticated as a plug-in
Prius but it could come close with good control software.

Given the price spread of fuels, I think that I'd take a close look at an
equally small automotive gas engine. The thermal efficiency may be a little
worse but the price spread would probably make up for it. You'd also have the
ability to run on LP gas, which here in America at the moment, is cheaper per
BTU than either liquid fuel.

This suggestion is based on American fuel prices, of course. If they're widely
different there then just ignore this last bit 

Even with the diesel engine, it might be more economical to include the
ability to use partly LP. Propane is used as a power booster for diesel
engines but it can also be an economizer is the price per BTU is sufficiently
less. It has a high octane (low cetane) rating so a little diesel injection
is generally necessary to get the fire burning but still a significant amount
of propane can be used.

John
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
You can't turn [MS] shovelware into reliable software by patching it a whole lot. -Marcus Ranum


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## EVDL List (Jul 27, 2007)

> James Massey wrote:
> > For the sake of discussion (at this time), the motor is a series DC
> > motor, and the 'new' ICE is a small (euro?) diesel that only has
> > enough power to hold highway speed on a slight grade.
> ...


----------



## EVDL List (Jul 27, 2007)

G'day Evan, Neon John, and All

At 07:57 AM 15/07/2008, Neon John wrote:
>On Mon, 14 Jul 2008 12:21:38 +0100, "Evan Tuer" <[email protected]> wrote:
> >Why not use a sprag clutch instead, and then you can start the diesel
> >on the starter as required, either for continuous cruising or just to
> >go up hills. When going down hill, or any time you can manage on
> >electric alone, switch off the diesel so that it's not slowing you
> >down or using fuel.
>
>Same thought here. At first I thought you were using slang for sprag clutch,
>James, and then I realized that you meant a transmission-style dog clutch. I
>would NOT do that.

Well, I suggested that to the mechanical guy that I was having the 
discussion with, and he just looked sideways at me and gave a 
shudder. He then went over to a drawer and got out a dog clutch that 
is a spare for his race car, the same as he's put into 30-odd others 
and waved it at me and told me about its' power handling, 
reliability, etc. So this brings up a question, why would you choose 
a sprag clutch over a dog clutch? What is he likely to be seeing as an issue?

>It also seems like you've left out one other operating mode - charging the
>battery with the diesel. That would be quite important if you couldn't get to
>a charging station, assuming the diesel really will be insufficiently powerful
>to climb hills.

Insufficiently powerful to maintain highway speed (just like my 
Toyota Dyna truck is) on hills, so no electric boost and changing 
down gears and going up hill at 2/3 the speed that would be 
otherwise. So loosing electric boost doesn't incapacitate the 
vehicle, just makes it less pleasant to drive.

>The easiest way to do that is with a SEPEX motor. That gives you easy regen
>and charging capabilities. This wouldn't be as sophisticated as a plug-in
>Prius but it could come close with good control software.

No doubt, but availability of a suitable controller and motor makes 
it harder. The guy that would be the owner and principle builder is a 
hydraulic/mechanical engineer, and would be wanting to keep it as 
simple as possible. An AC system would also work, and possibly be 
more readily available. All the more weight, but a small (3 to 6kW) 
generator could be running from the diesel, just brought on in 
inverse proportion to the throttle.

The final decision will, of course, be up to the guy paying the bills.

>Given the price spread of fuels, I think that I'd take a close look at an
>equally small automotive gas engine. The thermal efficiency may be a little
>worse but the price spread would probably make up for it. You'd also have the
>ability to run on LP gas, which here in America at the moment, is cheaper per
>BTU than either liquid fuel.

Diesel is about 5% more than petrol, LPG is getting a 'push' here 
with a federal government subsidy, but doesn't work out hugely 
cheaper to run on than diesel.

>This suggestion is based on American fuel prices, of course. If they're widely
>different there then just ignore this last bit 
>
>Even with the diesel engine, it might be more economical to include the
>ability to use partly LP. Propane is used as a power booster for diesel
>engines but it can also be an economizer is the price per BTU is sufficiently
>less. It has a high octane (low cetane) rating so a little diesel injection
>is generally necessary to get the fire burning but still a significant amount
>of propane can be used.

LPG/diesel has been gaining popularity, mostly it seems by people 
looking for a power boost rather than an economy boost.

Another thing he'll need to consider is a streamliner canopy for drag 
reduction, in fact anything he can get away with to reduce drag.

Thanks for your input.

Regards

[Technik] James 


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## EVDL List (Jul 27, 2007)

>


> James Massey <[email protected]> > wrote:
> > G'day Evan, Neon John, and All
> >
> > At 07:57 AM 15/07/2008, Neon John wrote:
> ...


----------



## EVDL List (Jul 27, 2007)

Hi James,

>> ><snip> So this brings up a question, why would you choose
>> > a sprag clutch over a dog clutch?
>>
>>A sprag clutch is automatic in operation, which will make the system
>>transparent and easier for the user. The ability to start and engage
>>the diesel easily "on the fly" seems like a big advantage too.
>
> I used to have a motorcycle (when I was 16 it was freedom) with some
> kind of sprag clutch, just rev up and it engaged, but that was pretty
> low powered (70cc).

Nope, that's a centrifugal clutch  You don't want to use that
because it won't disengage itself until you basically stop.
Sprag clutch is a freewheel, or overrunning clutch, OK?

>
>> > What is he likely to be seeing as an issue?
>>
>>A sprag clutch can be hammered to bits very easily by an ICE,
>>especially a powerful one.
>
> I reckon that'd be it! He's a mad racer, so probably over-powered
> every sprag clutch he got near.
>
>> But, if you follow the application notes
>>and size and install it properly, there should be no issues.
>>I'd recommend leaving the engine flywheel and clutch plate in place,
>>so that you have the damping and the spring action to take the pulses
>>out, before the sprag clutch. You definitely need to avoid it
>>engaging and then freewheeling after every power stroke.
>>Otherwise, no problem, it should last forever.
>
> Well, I'll add it to the options to be discussed with the potential owner.
>
>>Also I agree with John, I'd definitely want to include regen somehow,
>>both for going down hills (if you have those in Oz),
>
> In our part of Oz there are some 'beauties' - the main highway
> heading south they wanted to build in a certain place since the 1940s
> but left it until 1984 as the cars needed to be powerful enough to
> make the climb...
>
>> or at least to
>>load up the diesel to its optimum efficiency point and get a bit of
>>charge back into the battery when needed.
>
> Well, the final decision on that will be the choice of the owner. He
> may decide to just go series hybrid with a 15kW-ish generator.

I doubt that's a good idea. If it's used mainly for this long
journey, you definitely don't want to introduce extra weight *and*
extra losses! A standard diesel truck would probably be more
economical, not to mention cheaper.

> It'd be a lot easier to implement control with a plain vanilla series
> DC motor instead of attempting to regen the 'spare' energy from the
> diesel using the traction motor, all depends on the budget though.

You can get a "bit" of regen from a series motor by seperately
energising the field with a high current, low voltage supply. You
don't need much charge current just to add a bit of "compression
braking" or charge the batteries a bit, even 20A is useful and you can
maybe find a cheap 3.3V supply to at least experiment with.


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## EVDL List (Jul 27, 2007)

On Tue, 15 Jul 2008 19:13:51 +1000, James Massey <[email protected]>
wrote:

>G'day Evan, Neon John, and All
>
>At 07:57 AM 15/07/2008, Neon John wrote:
>>On Mon, 14 Jul 2008 12:21:38 +0100, "Evan Tuer" <[email protected]> wrote:
>> >Why not use a sprag clutch instead, and then you can start the diesel
>> >on the starter as required, either for continuous cruising or just to
>> >go up hills. When going down hill, or any time you can manage on
>> >electric alone, switch off the diesel so that it's not slowing you
>> >down or using fuel.
>>
>>Same thought here. At first I thought you were using slang for sprag clutch,
>>James, and then I realized that you meant a transmission-style dog clutch. I
>>would NOT do that.
>
>Well, I suggested that to the mechanical guy that I was having the 
>discussion with, and he just looked sideways at me and gave a 
>shudder. He then went over to a drawer and got out a dog clutch that 
>is a spare for his race car, the same as he's put into 30-odd others 
>and waved it at me and told me about its' power handling, 
>reliability, etc. So this brings up a question, why would you choose 
>a sprag clutch over a dog clutch? What is he likely to be seeing as an issue?

A sprag clutch is one of a variety of one-way or over-run clutches. Almost
all starter motors have them in the pinion assembly to protect the motor in
case the pinion doesn't disengage after cranking. Most all automatic
transmissions also have them.

There are actually several types. Off the top of my head, roller and cam,
sprag, dog-bone (which is why I thought one-way clutch when you said "dog")
and spiral. 

The desirability of a one-way clutch in this application is that you don't
have to do anything to disengage it. Simply turn the diesel off. When the
diesel is started and its speed increases to slightly more than the other
side, the clutch engages automatically. By "slightly more" I mean a fraction
of an RPM.

No doubt dog and slot clutches like you were shown can handle more power for a
given size but that isn't an issue here. You're talking about a few dozen HP
and not several hundred. One-way clutches are common industrial powertrain
items and are available in sizes that can handle hundreds of HP.

A sprag or dog-bone clutch large enough for this application can probably be
had in a press-in assembly that looks somewhat like a needle bearing.

John
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
Beware the lollipop of mediocrity. Lick once and you suck forever.


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## EVDL List (Jul 27, 2007)

> James Massey wrote:
> > G'day Robert, All
> >
> > At 11:08 AM 15/07/2008, Robert wrote:
> ...


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