(Hypothetical) Electric Torque Monster

[Evoluent]

Alrighty then...

A campground I tend to work at uses Yamaha G1 and G22 Golf carts to haul stuff around, 2 of which have little tow hooks for the pull carts. Only thing is they don't allow gas carts, only electric. Now the big thing I've been trying to come up with is using something like a Elec. go kart motor and trying to rig something up so it has very low speed, but enough torque to haul a empty 17' x 8' Lo-Boy trailer. This is so it can be cost effective (Golf cart batteries are about $120 used in my area)
and useful at the same time. Anybody have some ideas? I also don't want to use an industrial electric truck motor.

 

[Denny]

You can't do what you want to safely. I used to sell and service E-Z-Go golf carts. Sorry but I won't help on this one.

Denny

 

[itsid]

well, it's about gear ratios again,
a high power motor (say from a fork lift) and an insane raio (say 14:1)

but cost effective??
IDK, a motor that has enough power is likely upwards of 800 bucks (refurbished)
a matching controller easily draws another 500 bucks off your pockets.

I wouldn't say it can't be done safely.. but I'd say it can't be done cheap!

Do the math
and see where you end up with;
the rest is about finding the motor that provides that kind of power, a matching controller and figuring out the gear ratio.

'sid

 

[Thingem3376]

I think I saw a thread for a DIY Motor Controller on Instructables, I dont remember how he made it though. Look it up.

 

[KartFab]

For a low price of only $2,500 you can call one of these your own.

http://airtug.com/products/trailer-mover-tugs/trailer-tug-heavy-duty-hd-electric/

 

[Denny]

Sorry Sid but you are wrong this time. Yes you can get the trailer to move but getting it to stop or turn a corner is another thing. You got to think about little things like that. I have plenty of experience towing things with golf carts (I built and used 2 wrecker golf carts) and stopping or turning with loads 2x the weight of the cart was always trouble even on hard pavement. I have the scars to prove it.

Denny

 

[crazykart]

Probably not feasible, but what about 2 rear axles with a high geared (say 15:1 or 20:1) regular motor on each wheel, then having the fron axle with 2 generators (?) That are shifted into during stopping to both slow the cart down quickly and help recharge the batteries. Could also use a regular car or truck disc brake system for the stopping power...?

Idk, I really dont, lol. Just spitballing.

 

[ghost civic]

traction problems....answer, dually rear axle

I don't know what a trailer that size weighs, but I would imagine that the size electric motor and battery requirements would mean the cost would be high. Maybe you can use a smaller motor with some crazy gear reduction, but then you are likely looking at some custom parts/fabbing ect.

I remember seeing a program about compressed air engines. One guy has a design for small truck/carts that have a rotary engine that runs on compressed air. Not really helpful to your problem, but I thought they were cool.

 

[crazykart]

A bit off topic ya. Compressed air engines are not really adiquet for towing applications. The ones I've seen are only made to go long distances at albiet decent, but slowish speeds, and arr on extremely light weight vehicles. Ussing one to tow a ton or more...I dont see it happening.

 

[Iron John]

I disagree that it cannot be done reasonably inexpensively or safely.

Gear it down. Adapt brakes from a motorcycle or compact car. Use series-parallel relays through a resistor bank (sealed beam headlights) and speed control is totally mechanical, streetcar style. (You'll only need two or at most three speeds - series, series-parallel, parallel).

 

[itsid]

Sorry Sid but you are wrong this time. Yes you can get the trailer to move but getting it to stop or turn a corner is another thing. You got to think about little things like that. I have plenty of experience towing things with golf carts (I built and used 2 wrecker golf carts) and stopping or turning with loads 2x the weight of the cart was always trouble even on hard pavement. I have the scars to prove it.

Denny

Hmmm..
well, point to the "wrong part" of my previous post then...

cornering, stopping, never mentioned anything related, have I?

So, very true is, that your construction must be able to do that safely;
that holds true for ANY vehicle, no matter if gas or electric...
and that wasn't part of the question at all
And the question was.. can it be done... is it cost effective.
It CAN be done.. likely NOT COST effective though...
and that's what my post states...

Which, in your opinion, is the wrong statement in there?

'sid


PS the feedtroll smiley is rather annoying, when there is NO troll in a thread...
or is it saying that you are trolling? (you aren't IMHO) *shrugs*

 

[Evoluent]

Alright. Lemme elaborate what I'm needing to do here. The trailer by itself weights about 2400lbs (Roughly 1090kgs) and it's needing to go up and down a hilled driveway at about 10-14 degrees for about a 1/4mi (.40km). At the WAY end but the road and on the back side of the driveway is a 30 degree incline. One of the G22s has a stronger motor than factory so it can haul more, but it's more strain on the batteries. So it'll haul the trailer, but only on a flat surface for about 200ft till the safety cutoff kicks in and shuts it down to cool off. (I still don't get why they demand electric when everything else is gas and poorly tuned, but anyways) With a trailer like that I'm gonna need at LEAST 130 ft lb of torque to get it going, then I can use the momentum to assist the thing I'm making. I've also thought on taking something like a large factory electric UTV nand stripping the motors from that. Those have about a 30:1 gear ratio. I'm going to be using an old Yamaha G1 frame and body for this.

Also Sid and Denny... keep your personal disagreements outta my posts? This is a Drama Lama free zone.

 

[itsid]

There's no disagreement, he said I was wrong, and I asked what exactly was wrong

Anyways..
to move the trailer alone up that incline you need at least 11kW of power. at walking speeds.
I don't know what a G1 weighs in at.. but I assume another 3-4kW should do

So, what you'd need is a motor with a constant rating of 15kW or more.

Oh and indeed the brakes would need a serious upgrade on that G1 for the downhill part

'sid