Backhoe control stick idea.

alchemysa · Sep 4, 2008

(I first put this in the kubota forum but I probably should have put it here. My apologies for the dual post)

My sketch attached shows an idea for a backhoe dipper/bucket control that uses a rotating handgrip to control the bucket instead of a left/right lever movement. Something like this would seem fairly intuitive to me, as the bucket would mimic the rotation of the hand.

Theres no great engineering required here. The rotating handgrip simply pulls the valve up and down, just the same as the existing lever does.

This idea seems so simple there must be something wrong with it. Has it already been tried and rejected?

An even simpler design would use a short lever on the end of the hand grip instead the gear arrangement. It would depend on how much force is required to pull the bucket lever up and down.

My tractor is 300 ks away so I can't actually see it to see how practical or impractical this idea might be. From memory the up/down travel required is only about an inch each way.

john_bud · Sep 4, 2008

I would think it could work, but would the bucket curl when moving the lever forward and back?

How about making it a verticle handle that you still curl with your hand ?

srjones · Sep 4, 2008

I like it! It seems very intuitive. What if you used a motorcycle throttle instead?

bal0123 · Sep 4, 2008

I will tell you what is wrong with the idea. It is a great idea but the problem is how much force it takes to push or pull the spool in the valve itself. The reason they put the long or tall control rods on the backhoe control valve is so that you have the ease of leverage. The newest and most up to date thing is the pilot control valves. They take almost no effort at all to control and is what is coming out on all the new machinery. Very poplar with equipment operators.

Matt_Jr · Sep 4, 2008

That's an awesome idea. I wonder if the only reason we havn't seen it is 'cause the curling torque required of the wrist would cause a lot of fatigue to over come the pressure in the valve (resulting in carpal tunnel's) during prolonged use? The length of the joy sticks are able to over come that easily.

bal0123, looks like you beat me to it

alchemysa · Sep 4, 2008

john_bud said:
I would think it could work, but would the bucket curl when moving the lever forward and back?

How about making it a verticle handle that you still curl with your hand ?

john_bud. As long as there are some properly located joints in the linkage the bucket should not be affected when moving the stick backward and forwards.

srjones. Theres probably something that can be salvaged from a bike throttle but remember the grip has to push as well as pull.

bal0123. and mattjr. The force required to move the spools is something I wondered about. That's why I suggested a gear on the handgrip instead of a lever. To reduce strain I wonder if it would it be hard to electrically power assist or actuate the rod?

I've seen pilot controls but never used them. I guess they are power assisted. I don't think they'll be appearing on kubota compact tractors for a while!

Matt_Jr · Sep 4, 2008

alchemysa said:
To reduce strain I wonder if it would it be hard to electrically power assist or actuate the rod?

Now there's a thought.

Egon · Sep 5, 2008

How about an electric over hydraulic controller. Sorta like Fly by wire system. This could miniaturize the the controller, hand actions and force needed. The controller could easily be moved for right or left hand operation and be adjustable for individual preferences.

Speed of implement versus hand movement speed and range could also be adjustable for each individual!

With a wire controller it should be easy to have different set ups in the way the controller is actuated. Pick a controller that has physical movement characteristics that suit you!

alchemysa · Sep 5, 2008

Egon said:
How about an electric over hydraulic controller. Sorta like Fly by wire system. This could miniaturize the the controller, hand actions and force needed. The controller could easily be moved for right or left hand operation and be adjustable for individual preferences.

Speed of implement versus hand movement speed and range could also be adjustable for each individual!

With a wire controller it should be easy to have different set ups in the way the controller is actuated. Pick a controller that has physical movement characteristics that suit you!

Hey I'm trying to keep it simple..

. But whatever method is used to actually move the valve spool, I think the key ingredient is the rolling hand grip. This lets the hand 'mirror' the action of the bucket and would feel pretty natural I think. The action would be similar to if you were reaching out and scooping sand with your own hand.

Richard · Sep 5, 2008

Cool idea. It will also allow anyone to recognize just who is utilizing this by noticing their normal left arm and their Popeye right forearm!!

goneandbrokeit · Sep 5, 2008

How about getting it to work of a Wii controller!

Egon · Sep 5, 2008

normal left arm and their Popeye right forearm!!

Change that legs and aren't you looking at a Harley Rider from days gone by?

Taylortractornut · Sep 8, 2008

Koerhing, Insley, and Bucyrus Erie all tried a similar set up on their nydraulic excavators and it was unnatural feeling, and very very fatiging. It was a new idea from the old set up of hand and foot pedals that were all over the cab. They were back before I was born but I have had to operate a few of these and it makes your whole body ache the first 2 days. If you dont like the wobble stick you should trie the 3 lever Case setup with 2 pedals for swing or a Ford New Holland multi stick 4 levers. They are push pull and are very easy can be a little hard on the hands on a bigger machine I have on Old Ford hoe and it like that I also like the Case setup to. For beginners they like the push pull. Ive dug many miles of pipe trenchs and stumps with both kinds and like them.

Lasgambler · Sep 8, 2008

Matt_Jr said:
I wonder if the only reason we havn't seen it is 'cause the curling torque required of the wrist would cause a lot of fatigue to over come the pressure in the valve (resulting in carpal tunnel's) during prolonged use?

Thats what I was thinking. I'm sure there's some Lawyers, waiting, hoping someone does introduce this design.

CCWKen · Sep 8, 2008

Brilliant!!!!!!!!! Great idea. A little refinement to cover the gearing would go a long way. Keep in mind that you'd have to use two single valves as movement on one axis is horizontal and one is verticle. I still like it and it leaves the option open for twist motion as well. I may have to swipe the idea.

alchemysa · Sep 9, 2008

CCWKen said:
Brilliant!!!!!!!!! Great idea. A little refinement to cover the gearing would go a long way. Keep in mind that you'd have to use two single valves as movement on one axis is horizontal and one is verticle. I still like it and it leaves the option open for twist motion as well. I may have to swipe the idea.

On most backhoes I think you'll find the dipper and bucket valves are both vertical. The sideways movement of the lever pulls the bucket spool up and down.

Please do swipe it and see if it works. It may not even need gearing. A simple lever connected to the linkage may be as effective. Fatigue may not be a big factor on a small 'domestic' tractor. My limited experience is that they usually only get used for relatively short periods.