Power Steering Cylinders--How Does One Work?

[npalen]

I see some power steering setups with a single cylinder and some with doubles. My question is with regard to a single cylinder of convention design where the displacement on the rod side of the piston is quite a bit less than on the base side. What keeps the steering from being much faster when the cylinder is retracting while it takes much less fluid to move the cylinder a given amount?
I "get" the double rod design where the displacement is equal on either side of the piston or the twin cylinders where the net displacement is the same.

 

[PILOON]

While not sure I'd simply suspect that either the difference is really not noticeable, that or perhaps a restrictor is incorporated on the favored side.

 

[Industrial Toys]

I'm guessing that the flow demanded for steering simply compensates. There is amble in either direction. Who knows? You may notice it works a bit faster one way, but who thinks of that?

I always wondered how power assist steering works.There must be a valve that senses the slightest bit of torque in the steering linkage.

 

[Leejohn]

2 cyls has a crossover valve. One DA cyl you well see the steering wheel doesn't return to the same spot. There is another system that the steering head is the pump and also the wheel well not return to the same spot. I forgot what each system is called.

 

[Industrial Toys]

Yes. Some off road equipment has a manual pump in the steering box, like my Kubota Loader. You have some hard (hydraulic) steering with the motor turned off and then full power steering with motor running.

 

[PILOON]

Yes. Some off road equipment has a manual pump in the steering box, like my Kubota Loader. You have some hard (hydraulic) steering with the motor turned off and then full power steering with motor running.

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LOL, my l'il Mitsu has no power steering but I always planned on correcting that.
I bought on EBay the proper valve device and have a suitable cylinder.
Just need to make the bracket (and I weld) to anchor the cylinder to the frame and already have the ball joint for the Pittman arm.
Even tho retired I have not found the time to make it happen.
LOL, there is always tomorrow!
Funny how you learn how to work around short comings, and oddly enough 60% of my tractor work involves FEL work, you'd think I'd be motivated.
Even without power assist I can spread and grade a 12 wheel dump truck load of crushed within 1 hour average time so all is not lost.

 

[fatjay]

I added hydraulic steering to my kubota. It's just a hydraulic cylinder bolted to where the arm used to be for the manual steering. I added a steering column from a deere 318.

Steering is effortless now with the blower up on dry asphault. Best thing I did to my tractor.

 

[npalen]

Nice job on the plumbing!

 

[npalen]

Did a bit of calculating on the steering cylinder on my tractor to see how much difference between the rod side and base side of the piston. Using 42mm bore size with a 18mm shaft size, I'm seeing rod side displacement at 81% of the base side which is a lot less difference that I had imagined. Feel free to verify my figures--I did make a mistake one time.
So tend to agree with the comment that it's really not noticeable and will check to verify that the steering wheel does not center at the same place each time the tractor is turned one way or the other.
That stands to reason given the difference in displacement but just never noticed it.
I agree that most folks couldn't care less about trivial details such as this but some of us are just plain gearheads.

 

[TMGT]

You'll notice most factory systems that use a single DA cylinder have very small rod diameters for the cylinder size. As you found out it leads to a neglegable difference in speed.