EV Digest 6473
Topics covered in this issue include:
1) Re: Wide vs Skinny Tires LRR
by "Phil Marino" <[EMAIL PROTECTED]>
2) RE: Wide vs Skinny Tires LRR
by "Phil Marino" <[EMAIL PROTECTED]>
3) Re: 14.4v 115 amp/hour Battery Juice
by "Patrick Andrews" <[EMAIL PROTECTED]>
4) Re: Chassi - Pack isolation
by David Brandt <[EMAIL PROTECTED]>
5) Accessory Drive Motor Data Test
by "Roland Wiench" <[EMAIL PROTECTED]>
6) Re: [EV] Re: Breaker mounting
by "Roland Wiench" <[EMAIL PROTECTED]>
7) Re: Wide vs Skinny Tires LRR
by GWMobile <[EMAIL PROTECTED]>
8) Re: Speaking of Hybrids
by Jack Murray <[EMAIL PROTECTED]>
9) Re: [electric_vehicles_for_sale] (fwd) VECTRIX Demo Bike Now Available For
Te...
by "Doug Hartley" <[EMAIL PROTECTED]>
10) Re: All of original Tesla patents
by GWMobile <[EMAIL PROTECTED]>
11) Please get us some more cars to plug in!
by nikki <[EMAIL PROTECTED]>
12) RE: All of original Tesla patents
by DM3 <[EMAIL PROTECTED]>
13) RE: Questions on EV
by "Tim Gamber" <[EMAIL PROTECTED]>
14) Zilla for the newbie?
by "Richard Acuti" <[EMAIL PROTECTED]>
15) RE: Questions on EV
by "Mick Abraham" <[EMAIL PROTECTED]>
16) Re: Speaking of Hybrids
by Lee Hart <[EMAIL PROTECTED]>
--- Begin Message ---
From: "Michael Perry" <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: <[email protected]>
Subject: Re: Wide vs Skinny Tires LRR
Date: Thu, 22 Jan 2026 19:34:44 -0800
----- Original Message -----
From: "Peter VanDerWal" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, February 16, 2007 2:35 PM
Subject: Re: Wide vs Skinny Tires LRR
> Umm, skinny doesn't ALWAYS win. There is more to LRR than just the
width.
> If all else is equal, skinny is /probably/ better, but not necessarily.
There is also finding a tire sized for the weight load of the vehicle.
Putting on a undersized tire (per vehicle weight) not only is unsafe, but
can cause the tire to act as if it were underinflated. (Again, more heat,
and possible premature failure.) Over-inflating tires (above manufacturer
ratings) might save on fuel, but can make the vehicle less managable.
Keeping tires properly inflated can make more difference than the tire
construction.
"In order to meet <CAFE> demands, <original equipment> tires are often
designed with a priority on reducing weight and rolling resistance and are
molded with slightly thinner sidewalls, shallower tread depths and use low
rolling resistance constructions and tread compounds." "Now, lets explore a
scenario where a High Performance replacement radial tire has a whopping
20%
increase in rolling resistance."
"If the vehicle equipped with standard Original Equipment low rolling
resistance passenger tires normally provided 25 mpg in the city and 30 mpg
on the highway, installing tires with 20% greater rolling resistance would
only drop fuel mileage by a calculated 3% (to 24.25 mpg) in the city, and a
calculated 5% (to 28.5 mpg) on the highway."
"Additionally, the easiest way to reduce rolling resistance to enhance fuel
economy is to make certain that the tires are properly inflated."
TireRack has had this drivel on their web site for years. They are in the
business of making money, not providing valid advice.
They use 20% as an extreme ( "whopping") difference in tire RR, but the
National Research Council has measured tire RR as low as 0.0062 and as high
as 0.0152. That is an increase of 145% from the lowest to the highest. If
TireRack had used that number, they wouldn't have reached the same
conclusion.
Sure, you should keep your tire properly inflated. But, if you want low
rolling resistance, get a tire with low rolling resistance, and ALSO keep it
properly inflated .
Phil
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--- Begin Message ---
From: Ricky Suiter <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: EV List <[email protected]>
Subject: RE: Wide vs Skinny Tires LRR
Date: Fri, 16 Feb 2007 12:59:55 -0800 (PST)
Wow! That's some fat rubber!
I don't know if there is a formula, but in theory the less contact there is
with the road the less friction you have to overcome.
I don't understand your reasoning. Can you be a little more specific about
this?
First, tires roll and don't slide ( for the most part), so how does friction
with the road enter into it? I thought most of the losses were due to
hysteresis in the tire itself.
This is from the TRANSPORTATION RESEARCH BOARDSPECIAL REPORT 286
" The rubber tire interacts with the hard road sur-
face by deforming under load, thereby generating the forces responsible
for traction, cornering, acceleration, and braking. It also provides
increased
cushioning for ride comfort. A disadvantage, however, is that energy is
expended as the pneumatic tire repeatedly deforms and recovers during
its rotation under the weight of the vehicle.
Most of this energy loss stems from the viscoelastic behavior of rub-
ber materials. "
This is a great treatment of tire RR. You can find it here:
http://www.trb.org/news/search_news.asp?q_aw=286&q_ep=&q_sw=&q_nw=&allsubjects=on&subjectradio=0&allblurbtypes=on&day=0&Lower_Date=&Upper_Date=&s=1&st=1&Submit1=Find+Blurbs
Second, if the tire were sliding, the friction force would depend on the
load on the tire and the coefficient of friction. The contact shape does
not come into it ( except for subtle effects on the friction coefficient
during extreme lateral loading)
I know that it seems to many, that narrower means lower RR, but I have yet
to see any data to support that, or a clear explanation as to why that would
be true.
We should base our decisions (such as which tires to buy) on solid
information - but, for this question (wide vs narrow) , it seems to be
unavailable. The best bet, now, is to look at the available RR data for the
tires that will fit your car and meet your needs.
Phil
On my Saturn conversion
I focused a lot on reducing losses in the wheels. The car had some no-name
195 width tires on it, which I think was the stock tire size. I ended up
putting
a 185/60R15 Goodyear Integrity tire on it. These are "fuel efficient" as
they
say on the web site. I have no rolling resistance numbers for them but they
are
used on a lot of OEM vehicles. Between going a little skinnier and the
rolling
resistance it made a good 10 amp improvement in current draw in the city!
>From there I bought some Kosie racing wheels from Tire Rack. The 15's
only weigh
12.6 lbs, which is ~8 lbs a piece less than the stock Saturn alloys! This
made the
biggest difference of all. Not only do they look good but what took 200
amps to
accelerate now only took 150 amps to accelerate just as quickly. The car
wouln't
roll quite as much after you took your foot of the go pedal (though I'm
sure if I
took it up to 50 and let off the pedal it would still take a few miles
before the
car came to a stop).
Rick
-------------------------------------------
I'm interested in this formula as well. I have fairly large tires
275/60/15 - about 10 inches wide and I'm thinking about changing them
to
a narrower tire. Would my money be well spent here?
John Grigg
http://www.austinev.org/evalbum/723
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Mark E. Hanson
Sent: Friday, February 16, 2007 5:09 AM
To: [email protected]
Subject: Wide vs Skinny Tires LRR
Hi,
Is there a formulae for tire width vs LRR? I need to buy new tires
for my electric Porsche and there are P155, P165 and P195 options. I
assume that the skinnier tire always wins in LRR but by what
measureable
percentage? Is there measureable data or a formulae for width, are we
talking about 5% range difference (or MPG) or is it a fraction of a
percent? When wider tires are used there's obviously a larger contact
patch area but the pressure to the road per square inch is decreased so
it may not be a huge percentage.
Best Regards,
Mark
---------------------------------
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--- Begin Message ---
Don's figures are correct. I was calculating a general figure and wasn't
paying much attention with the conversion from grams to lbs.
The price is not definite I did some research and 1000-1600 seemed like a
reasonable price.
I have worked with Sanyo cells in the past under High current draws without
problems. There is also a Panasonic prismatic cell I was configuring. If
anyone has used the A123 cells and knows the price I would like to know.
Sanyo UR18650F cells retain 80% after 500 cycles they also weigh 30g less.
I Thank everyone for there input. I am still in the process of starting
production and would like to obtain a ISO 9000-9001 certification. I will
keep everyone posted and will reply to new posts.
[EMAIL PROTECTED]
From: [EMAIL PROTECTED]
Reply-To: [email protected]
To: [email protected]
Subject: Re: 14.4v 115 amp/hour Battery Juice
Date: Sun, 25 Feb 2007 16:13:45 EST
A much better choice would be the A123. 50 cells would be 115 Ah by 4 to
get
to 14.4 volts is 200 cells. Take a look at this
_http://www.a123systems.com/html/a123racing/rcdevkitspecs.pdf_
(http://www.a123systems.com/html/a123racing/rcdevkitspecs.pdf)
Note under Cycle life performance, 100% DOD, various temperatures
At a discharge of 1C at 25 degrees C 1000 cycles and only down 95%
They weigh more and are a little larger but the trade off is well worth
it.
The A123 have a lot more performance and life cycles.
Don your figures look right to me. I wonder what are the price of the Sanyo
cells? If you take 1400 dollars and divide by 215 that comes out about 6.50
a
cell. This would be with no added cost for the BMS or case. The 1400 is
close
to what the Valence 100 Ah battery cost already done.
Don Blazer
In a message dated 2/24/2007 2:08:40 PM Pacific Standard Time,
[EMAIL PROTECTED] writes:
Hi Patrick, looks good. I am happy you are doing this.
The costs look very similar to the costs of the Valence U24 batteries, but
this is at your most conservative price.
I am getting a different energy density. Here are my calcs:
55 cells to get 115 Ah by 4 cells to get 14.8V is 219 cells.
219 cells at 0.0465 kg is 10.18kg = 22.4lbs
This gives a gravimetric energy density of approx 162 Wh/kg which matches
close the spec of 167 Wh/kg
A few other questions:
1) as you stated in other email notes, will this include a BMS for
balancing, over charge and over discharge?
2) any idea of the number of life cycles to 80% DOD? The specs state 500,
is this what you think they will do?
3) any thought given to using the A123 batteries?
thanks for your work.
Don Cameron
Don Cameron, Victoria, BC, Canada
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-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Patrick Andrews
Sent: February 24, 2007 1:30 PM
To: [email protected]
Subject: 14.4v 115 amp/hour Battery Juice
One of the posters suggested I configure a standard battery pack that
will
retrofit in most EV's.
This battery would be 14.4v @ 115a/h the package would be 10" x 8" x 8"
weigh 12 lbs and cost around 1400$ +/- 400$. I haven't put together a
definite price and will try and to configure batteries for all of your
specific needs. Hope this will give you and idea of the size and price.
Cells are Sanyo UR18650F the spec can be found at:
http://sanyo.wslogic.com/pdf/pdfs/UR18650F.pdf
[EMAIL PROTECTED]
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--- End Message ---
--- Begin Message ---
I had this happen in an escort with flooded batteries also. Completely
disconnect the pack and 12V side of the DC-DC converter and check again. In my
case, I was losing isolation in the converter, and had to send it off to be
repaired. If the same thing is happening to you, disconnecting just one leg
will not solve the problem, and disconnecting just one side of the converter
may not solve the problem, as it could be leaking through the case. This was
what was happening in my case, and trying to isolate the fault was fruitless,
as it would seem to move all over the car, as yours seems to be doing.
David Brandt
----- Original Message ----
From: Ted Sanders <[EMAIL PROTECTED]>
To: [email protected]
Sent: Saturday, February 24, 2007 5:34:33 PM
Subject: Chassi - Pack isolation
My apologies for such a long post!! I felt that it was needed to explain
the situation.
In late October I replaced the batteries in my EV with 18 US 2000 batteries
for a pack voltage of 108. I have numbered my batteries from 1 the negative
post of which connects to the negative terminal of the system and number 18
positive post connecting to the positive terminal of the system. On
December 28 I added two more US 2000 batteries to increase the pack to 120
volts. At this point battery number 1 was on the negative end of the pack
and battery number 20 was at the positive end of the pack. I also changed
the DC/DC converter to accommodate the extra voltage. I installed a regular
electrical box to make the connection between the pack and the DC/DC
converter. Prior to this the chassis and pack voltage was isolated except
when the charger was connected to the 120 volt AC source. When the charger
was connected to the AC source the chassis voltage was midway between the
charger output. I did not check to see if this was still true until mid
February.
On February l3 I decided to check to see if the chassis and the pack were
isolated. To my surprise I discovered that there was a potential exiting
between the pack and the chassis.
I had not driven the car for 13 days and the pack voltage was 126.8. The
negative terminal of the pack was 66.3 volts negative in relation to the
chassis. The positive terminal of the pack was 12.2 volts positive in
relation to the chassis. The potential spread was 78.5 volts. The
potential switched polarity in battery number 17. The negative post of
battery number 17 was 2.1 volts negative in relation to the chassis and the
positive post was 1.6 volts positive in relation to the chassis. I
completely disconnected the charger from the pack. The wires which connect
the charger were disconnected in the trunk of the car so they still run
below the body to the pack connections under the hood. This did not make
any difference. I unplugged the DC/DC from the pack. This did not make
difference. The 120 volt socket was still connected to the pack. I removed
the plug and found that it was taped with electrical tape where the wires
from the pack were connected. Also the wires were protected where they
entered the box.
Thirteen days later I checked these measurements again. The car had not
been driven. The total pack voltage was 125.8. The negative terminal of
the pack was 64.6 volts negative in relation to the chassis. The positive
terminal of the pack was 4.0 volts positive in relation to the chassis. The
potential spread was 68.6 volts. However, now the switch in polarity
occurred in battery number 19. The negative post of battery 19 is 0.6 volts
negative in relation to the chassis and the positive post is 1.5 volts
positive in relation to the chassis.
Since the total voltage of the pack has dropped only 1 volt in 13 days it
does not seem that this situation is causing a drain on the pack. All of
the cable have extra protection where they pass through metal.
I am looking for suggestions as to what has happened to cause a potential
between the pack and the chassis except when the charger is connected to the
AC source.
"Beano" 1981 Escort EV
Ted Sanders
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--- End Message ---
--- Begin Message ---
Accessory Motor Data:
Thread mill - Permanent Magnet DC Motor
CW Rotation - 8000 Rpm
Class N (200 degrees C) Insulation
Thread mill duty 2.90 HP at 130 VDC at 22 amps
Continuous duty - 1.75 HP at 100 VDC
A generator was belted off the motor at a 1:1 ratio to apply a load of 60
amps at 15 volts which resulted in:
Bat No Load Load Motor No Load Load
Volts Volts Volts Load Amps RPM RPM
12 12.6 12.4 9.0 825 225
18 18.9 18.5 10.5 1318 900
24 25.5 24.7 12.5 1805 1207
30 31.6 29.9 17.5 2304 1565
36 37.7 36.8 22.5 2785 2110
42 44.3 36.1 25.3 3275 2340
48 51.1 50.3 28.6 3878 2934
54 57.4 56.5 34.2 4250 3800
60 63.5 62.8 38.1 4826 4352
Stop test at 6o battery volts, because the motor rpm is too high for the
load generator. I was running two motors gain together which the above
motor amps would be divided by two to give a single motor results.
For example at 48 volt battery pack the ampere on one motor would be 28.6/2
= 14.3 amps on a generator load of 15 volts x 60 amps or 900 watts.
If the motors are rated for 22 amps, then ((22x900)/14.3)/746 = 1.85.6 hp or
for the two motors it would be 3.71 hp.
It is best to bring up the motor rpm first before applying any load on them,
which you can do with a A/C which has a clutch and a alternator which you
can turn on the loads after the rpm is up.
Roland
--- End Message ---
--- Begin Message ---
Hello Eduardo,
Yes, you can use approved PVC electrical enclosures such as the Carlon
Company. You should have a metal chassis plate inside any way for you
components. If breakers and contactors need to be install vertical, it is
best to install vent holes. We normally install these boxes that need
vented about 1/2 inch away from the back mounting surface with four each
nylon spaces. We than drill a roll of holes in the back that is above and
below the chassis plate that is also mounted in the box with about 1/4 inch
standoffs.
Glue on a screen in the inside of the box over these holes.
Roland
----- Original Message -----
From: "Eduardo Kaftanski" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, February 25, 2007 1:31 PM
Subject: Re: [EV] Re: Breaker mounting
> On Sun, Feb 25, 2007 at 01:39:29PM -0500, Phil Marino wrote:
> > I just checked my Airpax breaker ( 250 A, 125V) and it mounts with 10-32
> > screws. I bought it from a surplus place a few months ago.
> >
> > I also checked on the Airpax site - all breakers in the series JAE, JRE,
> > and JLE use 10-32 mounting screws. Mine is a JLM series. I would be
> > surprised if a large and relatively heavy breaker were mounted with 6-32
> > screws. Maybe Joseph's breakers are a smaller size.
>
> Thanks to all for the input. I found some long screws that fit (dont ask
> what
> they were) and I used a dremel tool to cut them. Its now mounted :)
>
> What brings me to the next question:
>
> I am installing the breaker, some relays and contactors inside a PVC
> box,
> normally used for exterior 220volts instalations.
>
> -Should I make sure its sealed? Or the other way around, should I mount a
> small
> fan to ventilate it?
>
> And... Can I install the amperimeter shunt inside? or does it get hot in
> operation? (Max 400amps, continiuos 100amp)
>
> Thanks.
>
> --
> Eduardo K. | Darwin pone las reglas.
> http://www.carfun.cl | Murphy, la oportunidad.
> http://e.nn.cl |
> http://ev.nn.cl | Yo.
>
>
--- End Message ---
--- Begin Message ---
I wonder if you eliminated all tire hysteriesis if you would also have
to elminate all suspension travel to lose that loss as well. Otherwise
would all the hysterisis just ransfer to the suspension as spring
heating etc? And isn't it still the same energy loss?
That said remember the cross section the tire presents to the AIR is
directly proportional to the tire cross section and the amount of
AERODYNAMIC drag the tire creates. Thus a tire twice as wide for the
same height will create twice the aerodynamic drag.
At speeds above 30 mph the aerdynamic resistance of the wheel is
significant -especially on other wise low drag car bodies.
There is a reason even slow flying planes put wheel tear drop covers on
their landing gear!
Look at a cessna or cirrus!
On Sun, 25 Feb 2007 2:25 pm, Phil Marino wrote:
From: Ricky Suiter <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: EV List <[email protected]>
Subject: RE: Wide vs Skinny Tires LRR
Date: Fri, 16 Feb 2007 12:59:55 -0800 (PST)
Wow! That's some fat rubber!
I don't know if there is a formula, but in theory the less contact
there is
with the road the less friction you have to overcome.
I don't understand your reasoning. Can you be a little more specific
about this?
First, tires roll and don't slide ( for the most part), so how does
friction with the road enter into it? I thought most of the losses were
due to hysteresis in the tire itself.
This is from the TRANSPORTATION RESEARCH BOARDSPECIAL REPORT 286
" The rubber tire interacts with the hard road sur-
face by deforming under load, thereby generating the forces responsible
for traction, cornering, acceleration, and braking. It also provides
increased
cushioning for ride comfort. A disadvantage, however, is that energy is
expended as the pneumatic tire repeatedly deforms and recovers during
its rotation under the weight of the vehicle.
Most of this energy loss stems from the viscoelastic behavior of rub-
ber materials. "
This is a great treatment of tire RR. You can find it here:
http://www.trb.org/news/search_news.asp?q_aw=286&q_ep=&q_sw=&q_nw=&allsubjects=on&subjectradio=0&allblurbtypes=on&day=0&Lower_Date=&Upper_Date=&s=1&st=1&Submit1=Find+Blurbs
Second, if the tire were sliding, the friction force would depend on
the load on the tire and the coefficient of friction. The contact
shape does not come into it ( except for subtle effects on the friction
coefficient during extreme lateral loading)
I know that it seems to many, that narrower means lower RR, but I have
yet to see any data to support that, or a clear explanation as to why
that would be true.
We should base our decisions (such as which tires to buy) on solid
information - but, for this question (wide vs narrow) , it seems to be
unavailable. The best bet, now, is to look at the available RR data
for the tires that will fit your car and meet your needs.
Phil
On my Saturn conversion
I focused a lot on reducing losses in the wheels. The car had some
no-name
195 width tires on it, which I think was the stock tire size. I ended
up putting
a 185/60R15 Goodyear Integrity tire on it. These are "fuel efficient"
as they
say on the web site. I have no rolling resistance numbers for them but
they are
used on a lot of OEM vehicles. Between going a little skinnier and the
rolling
resistance it made a good 10 amp improvement in current draw in the
city!
From there I bought some Kosie racing wheels from Tire Rack. The 15's
only weigh
12.6 lbs, which is ~8 lbs a piece less than the stock Saturn alloys!
This made the
biggest difference of all. Not only do they look good but what took
200 amps to
accelerate now only took 150 amps to accelerate just as quickly. The
car wouln't
roll quite as much after you took your foot of the go pedal (though
I'm sure if I
took it up to 50 and let off the pedal it would still take a few miles
before the
car came to a stop).
Rick
-------------------------------------------
I'm interested in this formula as well. I have fairly large tires
275/60/15 - about 10 inches wide and I'm thinking about changing them
to
a narrower tire. Would my money be well spent here?
John Grigg
http://www.austinev.org/evalbum/723
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Mark E. Hanson
Sent: Friday, February 16, 2007 5:09 AM
To: [email protected]
Subject: Wide vs Skinny Tires LRR
Hi,
Is there a formulae for tire width vs LRR? I need to buy new tires
for my electric Porsche and there are P155, P165 and P195 options. I
assume that the skinnier tire always wins in LRR but by what
measureable
percentage? Is there measureable data or a formulae for width, are we
talking about 5% range difference (or MPG) or is it a fraction of a
percent? When wider tires are used there's obviously a larger contact
patch area but the pressure to the road per square inch is decreased so
it may not be a huge percentage.
Best Regards,
Mark
---------------------------------
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in the Yahoo! Answers Food & Drink Q&A.
_________________________________________________________________
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--- Begin Message ---
I've been looking into using a differential instead of the chain or belt
drive. The chain, while very inexpensive, is too noisy. The belt-drive
is expensive, but as far as I've seen it also doesn't have pulley pair
for a 5:1 ratio, it also requires a rather large wheel pulley in any case.
I'd be nice to find a one-way and 5:1 belt-drive that wasn't over $1,000
that could solve my problem, if anyone can point me to that solution
that'd be great, I've kinda had to give up on it.
The T-bird IRS looks interesting, but it is very heavy, the mn12 info
http://www.mn12performance.com/mn12how-to/irs/irs.html says 150lbs with
axles. (and btw, it shows the half-shafts with a seperate axle, so to
shorten them, you can just cut and repline one end of the axle, no
welding etc needed).
I'm looking into using a Ford 9" for a number of reasons, mostly that
they are heavily supported by the aftermarket. You can buy them
complete with all new parts. Aluminum cases are available, aluminum
spools, aluminum pinon supports. Widest range of gears available up to
7.33:1 and other stuff. An aluminum setup would not be cheap,
(and actually Ford sells an aluminum 8.8 IRS unit for the cobra mustang,
but I'm sure that is big bucks!) but it is available to save weight, and
also gears that are lightened to save another couple lbs.
What is makes the differential approach interesting is that I'm thinking
it could be used to also get a neutral gear for the hybrid. I looked
into the one-way bearings and one that can handle a lot of torque are
expensive. If you have an open differential and one side (wheel) is
allowed to turn free, this essentially puts it in neutral, the motor
driving the pinion can be stopped, and the other side spins in reverse
rotation. If you hold the one side stationary, the motor turns the
other wheel, but at only half the gear ratio. If I could get a 10:1
gear for the 9", that would work well, but given 7.33:1 is the most I
could find, I also need a way to lock the two axles to get the full gear
ratio.
So now it looks like I can have a two-speed trans with a neutral.
What concerns me most is whether the spider and side gears can handle
the rpm of running at 70mph (1500rpm) without the pinion moving or
moving slowly, as they are really designed to just handle small
differential speeds of a temporary nature (i.e. turning) there is no
real bearings for them.
I've also got to construct a way to hold stationary and lock the two
axles. The current idea is to use some solenoids. To lockup, I'll
place force on the free one axle into the diff to bind up the spider
gears, which is essentially how a limited-slip works, but inside-out.
To hold it stationary, I could force it the other direction into a disc
pad.
Another option I've looked into is using a planetary gear setup,
http://matexgears.thomasnet.com/item/all-categories/lgu-146-m/5mef20?&seo=110,
but I still need to come up with a neutral. The solution here is to
allow the outer ring of the planetary to also rotate. These gears are
designed to have it stationary to get the 5:1 gear, they are not
particularly inexpensive either, so I hate to plunk down the funds to
find I can't get it to work, whereas I have a 9" differential to test
with already.
Jack
Lee Hart wrote:
Could you clarify this please? I've never seen a
rear wheel with a hollow shaft
Roland has it right; 1963-1980's Corvettes and 1665-69 Corvairs have large
diameter pipe as their rear axle, with universal joints at the inner and outer
ends. They look just like a typical front-engine rear-drive vehicle's drive
shaft.
We are working on this very problem in our Sunrise. We decided to use a 1989-97
Ford Thunderbird rear end. These cars have fully independent rear suspension,
with everything mounted to a subframe that is easily removed. The differential
mounts to the subframe. Axles with universal joints connect each side to the
wheels. Upper and lower wishbones run from the differential to the wheel, with
a coil spring.
The problem is that we have to narrow the track about 10". That means cutting
those solid axles, shortening them, and welding them back together. We well may go
to tubular axles to make this easier/stronger.
BTW, the first prototype will be a DC system (to see how the Sunrise performs with a
simpler cheaper drive system). We have a WarP 9" motor on order. The
differential is being changed to 5.14:1 gears. It will be flipped upside down, and
use dry sump lubrication to reduce losses. The motor will mount directly to it
through a spider coupler (no clutch or transmission).
We're leaving room for even a WarP 11" motor, and the T'bird differential has huge
8.9" gears, so if someone wants to go drag racing, this setup should be strong
enough to do it!
--
Lee Hart
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4:59 PM EST
Hi Charles,
Last fall Vectrix had expected to be shipping the first bikes in Europe
around the end of February. Can you heard any update or news about this?
Thanks.
Best Regards,
Doug
----- Original Message -----
From: "Charles Whalen" <[EMAIL PROTECTED]>
To: "EV Discussion List" <[email protected]>
Sent: Sunday, February 25, 2007 3:52 PM
Subject: Re: [electric_vehicles_for_sale] (fwd) VECTRIX Demo Bike Now
Available For Te...
I agree completely. One should never invest in any EV-related venture more
than one can comfortably afford to lose, because as you point out, the
history of the last 40 years (and longer) would indicate that the odds are
more than likely that one will lose at least some and quite possibly all
of
one's investment.
Charles Whalen
--- End Message ---
--- Begin Message ---
Ok fair enough. But you can go to freepatentsonline.com once you have
done your text search through the old patent text on google.
You sign up for a free login name on that site and then you can download
and print a pdf of the patent. (The older patents take a minute to
create a pdf but it works)
The key is you can now search the text of old patents on google. You
can't do that anywhere else that I know of. So you can find anypatent
that mentions tesla anywhere in the patent.
Remember for old battery patents use "galvanic".
Electric current was known as "electric fluid"
And there are other differences in terminolgy in older patents. Like
electric "pressure"
Some old high voltage generators are called "electric motors"
Leyden jars are batteries then too.
On Sun, 25 Feb 2007 2:25 pm, Death to All Spammers wrote:
Uh, because you can't print out the patent from Google's patent search
results.
You can print a page or two or a diagram or two, but it doesn't let
you
print the whole thing.
Try it yourself.
If there's a workaround other than Alt-PrintScreen, please advise.
When I want to save something that I can't "right-click" or get ahold
of any other way, I visit the site with Internet Explorer, open
"Internet Options", go to the History section, open "View Files", then
copy it from there. You might try that.
www.GlobalBoiling.com for daily images about hurricanes, globalwarming
and the melting poles.
www.ElectricQuakes.com daily solar and earthquake images.
--- End Message ---
--- Begin Message ---
Hi Everyone!
We got some sneaky pictures of our new charging point today!
http://www.bevob.org.uk
Nikki.
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Actually, you can get any patent for "free" (with the right sw} if you go
to: http://www.uspto.gov/
I purchased the book because it has all (112) patents categorized and
neatly bound. Let me know how much ink and paper you will use to print
all 112 patents (at least 3 pages each). That in addition to the time it
would take justified buying the book for me (The book has (535) 8.5x11
pages).
"The Apparatus for transmitting electrical energy" 1,119732 is the one he
wanted to use to power small electric devices and charge EVs.
mario
> Subject: Re: All of original Tesla patents
> To: [email protected]
> CC: [EMAIL PROTECTED]
> From: GWMobile <[EMAIL PROTECTED]>
>
> Why do that when they are now free?
>
> That was the point.
>
> On Sun, 25 Feb 2007 7:56 am, DM3 wrote:
> > You can get a copy of all of Teslas patents in a book:
> > "The Complete Patents of Nikola Tesla" by Jim Glenn
> > mario
> >> > Date: Sat, 24 Feb 2007 20:49:31 -0800
> >> From: Geopilot <[EMAIL PROTECTED]>
> >> To: [email protected]
> >> CC: [EMAIL PROTECTED]
> >> Subject:Three pages of original Tesla electrical patents from the
> late
> > 1800's
> >> here!
> >>
> >> Three pages of original Tesla electrical patents from the late
> 1800's
> >> here!
> >>
> >>
> >>
> >>
> >
>
http://www.google.com/patents?num=100&q=tesla&btnG=Search+Patents&as_drrb_is=b&as_minm_is=1&as_miny_is=1776&as_maxm_is=1&as_maxy_is=1934
>
> www.GlobalBoiling.com for daily images about hurricanes, globalwarming
> and the melting poles.
>
> www.ElectricQuakes.com daily solar and earthquake images.
> > From: "Myles Twete" <[EMAIL PROTECTED]>
> To: <[email protected]>
> Subject: RE: All of original Tesla patents
> Date: Sun, 25 Feb 2007 12:20:44 -0800
>
> > On Sun, 25 Feb 2007 7:56 am, DM3 wrote:
> > > You can get a copy of all of Teslas patents in a book:
> > > "The Complete Patents of Nikola Tesla" by Jim Glenn
>
> > Why do that when they are now free?
> > That was the point.
>
> Uh, because you can't print out the patent from Google's patent search
> results.
> You can print a page or two or a diagram or two, but it doesn't let you
> print the whole thing.
> Try it yourself.
> If there's a workaround other than Alt-PrintScreen, please advise.
>
> -Myles Twete, Portland, Or.
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--- Begin Message ---
I think its great your interested in EVs but even 60 miles on lead acid
batteries is difficult at high speeds. The porsche is a good conversion
vehicle from what iv'e heard, but i doubt you will be able to make 60 miles
on one charge with lead acids. The solar panels are not a very good idea
because of the cost/extra range trade off. (Very expensive for very little
range improvement) If the prices do come down someday, it would definetly be
a good idea. In order to make 60 miles on lead acid batteries you may need a
pusher trailer or a more advanced battery pack. I have also heard that nimh
batteries are more expensive per unit of energy they hold, then li-ion, so
go for li-ion if you are going to use a more advanced battery pack.
From: Jason Franzman <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: [email protected]
Subject: Questions on EV
Date: Sat, 24 Feb 2007 23:38:52 -0800 (PST)
Hi, my name is Jason Franzman, I am a freshman in a Junior
College and I am looking into a engineering major and will hopefully be
transfering to UC Berkley. I am new in to this list and in my
research. I am sure before long you will be bored and annoyed by all
my questions. I am extremely interested in converting a car into an EV
for many reasons. First and for most, my goal is to save the
enviroment and to do this effectively I need the car to reach a
sufficent range of about 150 miles on one charge. I am looking into an
AC converting kit on Electro Automotive specifically the porsche 914 AC
kit. It costs about 13K not including batteries or the body but it
will reach about 150 miles on one charge and can go up to 100
mph. They advise that I use lead batteries but I am also looking into
either Lithium Ion but most likely Nickel Metal Hydride. Also I am
looking into solar panels which I will fit onto the roof, trunk and
hood since they are so flat.
The car will have a significant down
time after 60 miles since Berkely is only 60 miles from my house and
will be able to charge for about 7 or so hours before I return home. I
am looking into the hypothetical best car that I can build and then
from there I will downgrade based on the money.
To tell you the
truth I have about a million questions that I can think of to ask based
on my ideas. Some specific questions are will the solar panels( so far
I can only find ones that do about 6-8% that can bend enough to put on
a car) generate enough electricity to justify the money spent? What do
you think about the choice of car? What is one of the lightest cars
with the most surface area (for solar panels) and most efficent drive
trains in you opinion? Is a kit a good way to go and my last question:
is the Electro Automotive Company I mentioned earlier a reliable
company?
I am really excited to learn that there are other
people who care about the world around them and are willing to do
something about it. The main question that I have is what do you think
of my plan and do you have any advice that can help my pursuit. Any
help would be appreciated and thanks.
Jason Franzman
_________________________________________________________________
Buy what you want when you want it on Sympatico / MSN Shopping
http://shopping.sympatico.msn.ca/content/shp/?ctId=2,ptnrid=176,ptnrdata=081805
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--- Begin Message ---
Eesh...obviously I still barely know jack about EV's. I've been interested
in upgrading to a better controller for my Beetle. (That I just bought) I've
read the FAQ but I still have questions and from his production blog, Otmar
simply seems too busy to answer such noob questions so I'm hoping that
experienced Zilla EV'ers can help me.
First some background:
Currently I'm running the standard Curtis 1221B. Um...the motor is also a
ADC 6.7" Smaller than normal it seems from looking at the EV photo album.
128v of 8v lead batteries. 128-12v Sevcon DC/DC converter. The car has been
driven for years in this configuration by previous owners. I'm over-driving
the controller by 8 volts but the inrush blow is softened by a light bulb
resistor arrangement. Question #1: Does anyone see anything critically wrong
with this arrangement? Is the motor too small? It seemed to drive ok before
I took the worn out batteries out of it.
Question #2:
The Zilla seems kind of intimidating to me. Please help me understand if it
would benefit me or tell me if it would damage my motor or new 8v lead
batteries. As I understand it, a Zilla programmed to give me more than the
400 amps that the Curtis gives would let me accelerate faster, and perhaps
run at higher speeds at the cost of draining the batteries faster. Is this
correct? What maximum amperage setting is acceptable to hit 8v lead
batteries with? I don't want to damage them or shorten their life cycle.
Will the higher output of a Zilla shorten my motor or brush life?
Question #3: According to the FAQ, the Zilla will live longer if it's liquid
cooled.
Uh, I'm driving a '74 Beetle here. It has no front "grill" for radiator
airflow. I don't want to add yet another electrical load by placing a fan
over whatever heat exchanger I use for the fluid. Any ideas on how to
overcome this?
Question #4: Are there any Baltimore/DC Metro area EV'ers that have
installed their own Zilla 1k controllers who would be interested in working
with me on this upgrade when the time comes? I do NOT expect anyone to just
"do it for me". I want to be involved, hands-on. I'm smart and can be
taught.
I'm not trying to achieve "Warp Drive" here, I'm just trying to put a little
zip into the Slug Bug so I can scoot out of the way of an SUV if I have to.
Perhaps just setting the Zilla for 600-700 amps would be adequate but I have
no idea how much of a performance difference it would make or if it would
even be safe.
Thanks for your help in advance,
Rich A.
Maryland
_________________________________________________________________
Play Flexicon: the crossword game that feeds your brain. PLAY now for FREE.
http://zone.msn.com/en/flexicon/default.htm?icid=flexicon_hmtagline
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--- Begin Message ---
Jason Franzman said: "it will reach about 150 miles on one charge and can go
up to 100 mph."
[Mick says:] Jason, I caution you about such optimistic projections for a
backyard conversion using non-exotic batteries. If you significantly lower
your expectations now, you won't set yourself up for a big disappointment
later. VoltsPorche experts on the list should chime in, but I'd say your
range projection is too hopeful by a factor of 5. 100 mph also seems too
optimistic. Mick A.
--- End Message ---
--- Begin Message ---
From: Jack Murray
> I'd be nice to find a one-way and 5:1 belt-drive that wasn't over $1,000
> that could solve my problem, if anyone can point me to that solution
> that'd be great, I've kinda had to give up on it.
A v-belt style drive is inexpensive, and available in almost any ratio. You can
use an idler pulley or adjustable pulley to "de-clutch" it if desired. The main
drawback of v-belts is slightly higher loss.
> The T-bird IRS looks interesting, but it is very heavy, the mn12 info
> http://www.mn12performance.com/mn12how-to/irs/irs.html
> says 150lbs with axles.
Thanks for the excellent link! It does a great job showing what we are using in
the Sunrise.
There are *two* sizes of T'bird/Cougar differentials. This website describes
the big one, used with V8s. The smaller one is used in cars with the V6 engine.
the V6 version would save you 30-40 lbs.
> it shows the half-shafts with a separate axle, so to shorten them, you
> can just cut and respline one end of the axle, no welding etc needed.
The axles are hardened, so you can't cut new splines without annealing them,
machining, and then re-hardening them.
> What is makes the differential approach interesting is that I'm thinking
> it could be used to also get a neutral gear for the hybrid.
The spider gears in a differential aren't meant to run continuously. They have
very poor sleeve bearings, and straight cut gear teeth.
It sounds like what you want is the power split device out of a Toyota Prius.
It has the bearings to allow any shaft to run continuously at high rpm. The
Prius has been around long enough now that you can probably find a wrecked one
for parts.
--
Lee Hart
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