Need to know more about power steering

[OilFilter]

Originally Posted by oil pan 4

Main problem I see with that hydraulic motor is its only going to make like 80 foot pounds of torque.

Huh??? You can get a hydraulic motor in almost any RPM and torque rating you could ever want. If you find a good deal on a motor that isn't perfect, gear ratios, or pulley ratios, are extremely easy to change. Hydraulic motors are available in high speed, low speed, high torque, and low torque. Just like a gas motor. Your post doesn't make any sense.

But for that matter I am not talking about a complete engine replacement, 80 ft lbs of torque is a LOT if it's just a booster.

[user removed]

Charles Gray, the EPA head of the hydraulic hybrid work (2006) with Parker Hannefin and the University of Michigan as well as Ford, stated that he could hold a 500 horsepower hydraulic motor in his hand.

Check US 7677208, my patent for a hydraulic in wheel drive as well as 10,000 other applications, including the ability to store electricity.

Here's a link
http://www.google.com/patents/US7677208

regards
mech

[jray3]

Reusing the original power steering pump and just adding an electric motor via belt drive or shaft coupling is SOP in the EV conversion world. I have one friend who did this on an electric Dodge Dakota, but he only turns the pump on for low speed parking maneuvers. If he's moving at any speed, no power required. Another friend used the Toyota MR2 electric power steering pump in his electric F250 pickup. It stays on more of the time, but also does the job fine.
Only caveat is that if you turn the pump on in the middle of turning the steering wheel, it can move suddenly with a violent jerk.

[oil pan 4]

Originally Posted by OilFilter

Huh??? You can get a hydraulic motor in almost any RPM and torque rating you could ever want. If you find a good deal on a motor that isn't perfect, gear ratios, or pulley ratios, are extremely easy to change. Hydraulic motors are available in high speed, low speed, high torque, and low torque. Just like a gas motor. Your post doesn't make any sense.

But for that matter I am not talking about a complete engine replacement, 80 ft lbs of torque is a LOT if it's just a booster.

I was talking about that one small motor you linked.
I asked what motors you think would be good for doing a hydraulic hybrid, you linked that little motor. I don't think its big enough.

[OilFilter]

Originally Posted by oil pan 4

I was talking about that one small motor you linked.
I asked what motors you think would be good for doing a hydraulic hybrid, you linked that little motor. I don't think its big enough.

Did you miss the part where I said "this is just one example"? I'm not going to write you a complete hydraulic conversion manual.

But more on topic, yes, a 37hp motor would do WONDERS in a hybrid. That is likely enough power to move a pickup truck down the highway at 55mph. It could also probably accelerate to at least 25mph without any additional power. An equivalent sized electric motor would cost more, weigh more, be physically larger, and need hundreds of amps to power it.

I'll remind you that the diesel engine in my F250 was rated at only 155 horsepower in 1983. Yet that was enough power to tow 15,000lbs.

[OilFilter]

Originally Posted by Old Mechanic

Check US 7677208, my patent for a hydraulic in wheel drive as well as 10,000 other applications, including the ability to store electricity.

Here's a link
Patent US7677208 - Radial rotary engine with energy storage - Google Patents

regards
mech

That's really cool, I've always wondered why MFRs don't put more effort into wheel motors of some type, seems like it could be not only more efficient, but cheaper to manufacture.

I would love to see the day I could buy such a thing as a conversion part for other vehicles. Much like all the electric motors that are available these days. I think trucks really need a way to reuse their braking energy, and batteries are not a complete solution.

[OilFilter]

Originally Posted by jray3

Reusing the original power steering pump and just adding an electric motor via belt drive or shaft coupling is SOP in the EV conversion world.

It probably would be relatively easy to directly couple an electric motor to the stock PS pump and spin it at idle speed. No question that would be enough power. And it would sure make the plumbing easy! Might be able to find a motor with a longer duty cycle than that other pump I was looking at.

[oil pan 4]

Originally Posted by OilFilter

It probably would be relatively easy to directly couple an electric motor to the stock PS pump and spin it at idle speed. No question that would be enough power. And it would sure make the plumbing easy! Might be able to find a motor with a longer duty cycle than that other pump I was looking at.

The largest motor that I could find and would fit is 3/4hp that weighs about 33lb. and cost $400 for a decent one or you can buy a cheap $150 motor every few weeks as they burn up.
It might have a very long duty cycle if it were not in a 200'F environment.
I already know it takes about 200 watts to spin the power steering pump over at close to idle speed at no load (not trying to turn the steering wheel) just letting all the fluid bypass.
Note pump speed may be slightly higher than crank speed, in at least some vehicles the power steering pumps appears to be slightly over driven. So pump speed may be closer to 1000rpm.
If it takes 1000psi to drive 2.5gpm through a steering box that is about 1.5hp when turning the wheel.
Not a problem for a 12v DC motor at room temperature or start up, in those conditions you could run a motor like that at 200% load for a minute or 2 with no ill effect. But start with the motor at 200'F warmed from heat coming off the engine, I would expect that motor to be scorching hot after maybe 30 seconds of use and if it has a thermal over load it will trip.
This is why I am going to use a hydraulic power unit slung down low and forward, maybe even just behind the bumper (not next to the scorching hot engine) and only weighs about 20lb.

This mod is fairly common to do in electric vehicles, but the motor driving the power steering pump isn't sitting near 900'F exhaust manifolds.