Hi Team,
I was having a discussion on the tracks the other day about power steer and learnt that there are some cars that have an electric power steering pump.
This made me wonder - Steve / Ross / Other Gurus - how feasible (cost vs effort vs reward) would it be to set this up on our cars?
i.e. perhaps with a bigger alternator to power it, it could be a simple standalone system that would free up a bunch of space off the passenger side of the engine for other goodies - i.e. endless airs / aircon / whatever.
What do we think?
Cheers,
Electric Power Steer
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gwagensteve
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Re: Electric Power Steer
There's a few different systems - pure electric - which assists the steering via an electric motor attached to the rack, and electro-hydraulic, where the electric motor runs a pump when required to the assist the rack in the conventional way.
In both cases, they are an emissions and fuel economy tool. By not running the pump when no steering is required, the engine doesn't have to produce as much power (less loss via belts, idlers etc) and so doesn't burn as much fuel.
Our mini was electro-hydraulic. It. was great until a fault code turned the assistance off.
There's a lot of tuning in getting these systems right - feel etc, which is an effect of how they are programmed.
In terms of a stand alone electrically driven hydraulic pump - these things exist and are common on trucks for tailgate loaders. The buggies built for ragged edge 4X4 all had electrically driven hydraulic pumps for the rear steer.
They are noisy, bulky, heavy, power consumptive, and, I'd wager, not designed for continuous duty like they'd see in a front steering application. I think the hassle of mounting and powering one would make fitting a conventional power steering pump look like a breeze.
Steve.
Steve.
In both cases, they are an emissions and fuel economy tool. By not running the pump when no steering is required, the engine doesn't have to produce as much power (less loss via belts, idlers etc) and so doesn't burn as much fuel.
Our mini was electro-hydraulic. It. was great until a fault code turned the assistance off.
There's a lot of tuning in getting these systems right - feel etc, which is an effect of how they are programmed.
In terms of a stand alone electrically driven hydraulic pump - these things exist and are common on trucks for tailgate loaders. The buggies built for ragged edge 4X4 all had electrically driven hydraulic pumps for the rear steer.
They are noisy, bulky, heavy, power consumptive, and, I'd wager, not designed for continuous duty like they'd see in a front steering application. I think the hassle of mounting and powering one would make fitting a conventional power steering pump look like a breeze.
Steve.
Steve.
michaelpiranha2000 wrote: The rear is in great condition. but has a broken crown wheel and pinon
Re: Electric Power Steer
The Japanese market Sierra that my K6A came from had Factory electric power steer but I didn't get it with the engine.
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gwagensteve
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Re: Electric Power Steer
And it's important to recognise that that system comes from a 900kg car with 4" wide rims designed for urban use- It's assistance at parking speeds, and nothing more. It's won't turn 35" Krawlers up against a rock.
Later cappuccino models also had electric power steer. It turned off over 10 km/h
Steve.
Later cappuccino models also had electric power steer. It turned off over 10 km/h
Steve.
michaelpiranha2000 wrote: The rear is in great condition. but has a broken crown wheel and pinon
Re: Electric Power Steer
Monster truck at marks adapters BBQ the other week had electric motors running hydraulic pumps to run the steering and ride hight etc.
not realy electric power steer though
Mock
not realy electric power steer though
Mock
mugginsmoo welding grinding sanding painting my old shit in melb
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mightymouse
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Re: Electric Power Steer
Actually there are a few technologies all sort of bundled under electric power steer.
Major are electrically driven hydraulic pump, electrical over hydraulic ( really an electro-hydraulic servo ) and pure electric.
The pure electric use torque motors rather than motors as we traditionally know them - capable of producing torque without rotation
Many reasons for Electric Steer...
Certainly economy gains.... and that's a major design criteria., and sometimes purely as a means to move the hydraulic PS pump.
LARGE cusrrents drawn by these systems and often at low engine speeds which is where the alternator isn't very effective so.....
However it gets difficult with larger masses, larger Bosch systems use multiple actuators to develop sufficient torque for the job and are also justifed as driving intervention systems ( i.e. so the electronics can steer the vehicle.... ).
For a small 4WD IMO not there yet.
Major are electrically driven hydraulic pump, electrical over hydraulic ( really an electro-hydraulic servo ) and pure electric.
The pure electric use torque motors rather than motors as we traditionally know them - capable of producing torque without rotation
Many reasons for Electric Steer...
Certainly economy gains.... and that's a major design criteria., and sometimes purely as a means to move the hydraulic PS pump.
LARGE cusrrents drawn by these systems and often at low engine speeds which is where the alternator isn't very effective so.....
However it gets difficult with larger masses, larger Bosch systems use multiple actuators to develop sufficient torque for the job and are also justifed as driving intervention systems ( i.e. so the electronics can steer the vehicle.... ).
For a small 4WD IMO not there yet.