Hydraulic Chute Turning Motor....

[techman]

I have the same options on mine as well. My deflector actuator I got from a guy on eBay. It is a Kubota unit, but for a much larger snowblower, so it is larger and more robust. It has never had any water/ice problems.

I wired both drives into a small PVC junction box on the blower, and have a multi pin connector that plugs in when I attach the blower. In the junction box I installed a 5 amp self resetting circuit breaker (from Pep Boys) in each motor circuit. It protects the motors from damage if they are bottomed out. I have never had an issue with the rotate jamming after it bottomed out. You may want to look at the worm engagement to be sure everything looks okay.

paul

 

[techman]

Junkman:

Just FYI, the theoretical torque from a hydraulic motor is:

T = P x D / 2 pi

T = torque in 1n-lb
P = pressure in PSI (differntial across motor)
D = motor displacement in^3/rev
pi = 3.14159

Most motors develop less actual torque, by about 50~10% depending on design and efficiency. Remember that chute stops will still cause the torque to be applied to the worm. A pair of "cross port" relief valves in a small connection block can be had for about $100. This will allow a max torque to be dialed in for each direction, and protect the mechanics.

The motor Dooze used looks like it is a very small displacement gear motor. Most orbit type motors (like a Char Lynn) are by design low speed high torque, so be careful.

paul

 

[Don_Sullivan]

Paul;
I like your idea of the separate junction box for the SB controls and will borrow it with thanks - the existing arrangement is pretty ratty. The circuit breaker will make it possible to put a real mechanical stop on the chute if that turns out to be the best way to go. That's the top priority project as soon as the barn painting is done and the fences repaired.

Don

 

[Junkman]

Thanks for the information.... and a thanks also goes out to rbargeron for offering me a great motor. I now have the motor in hand and will be moving forward in mounting it on the snowblower. My first task is to determine exactly how I am going to mount it and then, once mounted, I will work on the hydraulics of the unit. The motor that I have is a Char-Lynn #101 1003 007. I don't know what the RPM or torque of this motor is yet, but I know that I will need to use the flow restrictors to slow it down. Are flow restrictors available in different restrictions? I know from Kubota that the BX operates at approximately 1800 PSI. I am not familiar with the cross port relief valves that you refer to. Could you explain more or point me toward a web page that will have more information????? Thanks for the help...

 

[Von]

Junkman, I know you like a project just as much if not more than me! But for all the cost and time, and then the worry that you might tear up that new blower. I for one would just build an electric rotator. Mine cost me less than $20.00 and only took about 4 hrs. of my time to make from start to finish! But your going to do what you want, so good luck with it! Von

 

[techman]

Junkman:

Your motor is a geroter type:

5.9 in^2 displacement (97cc)
1/2" NPT ports
1" straight shaft w/woodruff key
1800 PSI delta cont, 2400 inter.
585 RPM max

141 ft-lb (1690 in-lb) at 1800 PSI

This is a very high torque for the application.

A cross port, or crossover relief is two relief valves connected back-to-back and connected across the motor ports. When either port gets high enough to reach the setting of the relief, it opens and limits the pressure across the motor, and thus the torque. I found an example here: http://www.logichyd.com/g10xrblocks.htm

This is a small block and you must also order the screw-in relief cartridges as well.

As far as flow restrictors, you can get adjustable throttle valves, but for an application like this I would use a fixed orifice. The standard practice in industry is to take the end of your hose fitting and tap the inside bore. Then use a set screw to match the tapped hole. Drill a hole in the center of the set screw for the orifice. Trick is to heat the set screw red hot and let it cool first to "de-harden" it so it is easy to drill. Use some hydraulic compatible, removable Loctite (we use "blue Loctite") to make sure it stays in place. You will need to experiment with the hole size to get the flow you want. Start with 1/16" hole. After you get the right size, then loctite it in place. Make sure you get the chips out of the fitting and set screw before assembly.

To set the relief valves, back them out all the way to start. Bring them in a bit to see if there is enough torque. Just go enough to work well. Less is better I think. If the chute stalls or doesn't have enough force with the snow, turn the reliefs in a bit more under real conditions. Each relief will set the torque in one direction.

Have fun with it.

paul

 

[Junkman]

I admit that I am over my head on this project, but I am committed, so there is no turning back. How do you know what the settings should be for the "screw in relief cartridges"? Do you have a picture of what this valve looks like? I have found some inexpensive (under $2.00) screw in flow restrictors. web page

 

[techman]

Junkman:

It is not really very complicated. The relief valves look like:

http://www.sunhydraulics.com/cmsnet/cpp.aspx...lmsibbmx0d4lht3h0gdtnsm2

There is a screw adjustment (usually an allen wrench) that is on the end of the relief. The relief valves on the Kubota are fixed, set by shimming. The more common type is adjustable. When the adjustment stud is backed out, you have minimum pressure, and the pressure setting goes up as you turn it in. The setting is going to be the motor torque limit. So you would want to keep the setting as low as works, corresponding to the minimum torque required. If you find you need a bit more torque, turn it in a hair more. Think of it as a torque limit setting. You could contact a local hydraulic distributor who should be able to help out with the cross port reliefs.

paul

 

[techman]

Don:

Here is a shot of what I did

paul

 

[Junkman]

Von...... I thought about using the electric motor, but I like the idea of using the loader joy stick to move both the chute elevation and being able to rotate it as the same time. I couldn't do this on the fly with the electric. If I get this built and find that it doesn't work as well as I had hoped, I will then convert to electric, but only under duress... /forums/images/graemlins/grin.gif /forums/images/graemlins/blush.gif