New Idea - Top Link w/ Shear Pin

[kensfarm]

I have seen & read multiple posts regarding 3pt hitch damage.. most seem to be caused by using boxblades in reverse.. hitting a stone or a stump. This problem.. for some reason.. just seemed to stick in my head.. and I been thinking of a low cost.. after market solution. Has anyone ever seen or heard of a top link.. that includes a shear pin devcie? Here's my idea.. a top link w/ the normal functionality of being able to resize by turning.. but a modification to the middle section.. that has the sliding back & forth capability.. much like a PTO shaft.. the modified "sliding section" would then be secured w/ a shear pin in such a fashion.. that when breaking force is applied.. the top link would slide in/together.. or slides out/apart.. The sliding section could be limited.. so that when a breaking force is applied.. it could slide out.. but not apart.

This setup would provide a method to prevent the 3pt hitch from buckeling under extreme stresses caused by hitting a solid object.. the shear pin would give.. and force the implement to slightly rotate/pivot on the lower arms up or back. (similiar to a shear pin protected plow )

What are your thoughts on this device.. if it hasn't already been done.. I'm always looking for a way to retire early. I'm working to put a diagram & prototype together.. (a weldor could probably put this together as fast as I could draw it on paper) the sliding section can be as simple as two pieces of pipe.. one sliding inside the other. I thought this would provide an affordable.. easy.. after market solution.. that would save the 3pt hitch on the implement.. as well as help protect the tractor's rear components.

Looking for input.. idea's of why it would or would not work. Thankyou! Ken Davis

 

[Gary_in_Indiana]

Well, as one who has probably the least experience with such things, I'll ask the most basic of questions. Wouldn't the shearing of the pin result in a rather unceremonious drop of whatever implement is attached at the time? Also, wouldn't the pin likely shear when you're bouncing over some rough ground?

 

[MDNick]

While I think it is great to brainstorm, and any ideas are neither good nor bad until fully thought out and stormed to death, I can't see this one working.

The solution to the problem is not another dammm safety device. It's better operator training. I'll bet there are few repeat customers from this kind of damage. They learn not to do that again.

I want my top link connection SOLID. Nothing even remotely close in the system that might shear. Go over a bump, with a box blade, the shear breaks, and you may have 2 flat rears. Shear pins are there to prevent further damage, not provide a possible failure point that might cause damage by shearing. It is possible to limit travel of the slide after shearing, but I personally don't think it would work and wouldn't want one.

Sorry. But keep brainstorming. Every neat thing in the world was thought up by someone once.

 

[kensfarm]

Thankyou Gary..
"unceremonious drop of the implement"
The sliding section would have a stop point.. so that the top link ends would not separate/come apart completely. The implement.. like a boxblade.. would already be in contact w/ the ground.. but I'm sure it would jump some.

"bouncing over rough ground"
I was thinking the shear bolt would take normal forces much like the shear pin in a plow would.. but if you have a heavy implement.. and it's bouncing that much.. (for me.. that means slow down).. it could break the pin. Good point.. and def. a test this top link device would have to go through.. which probably would make this top link device have a implement weight limit.

Both very good points.. Thankyou!

 

[CTyler]

I'm just kinda thinking out loud here....not trying to rain or your parade or anything.

Isn't there more generally more force applied pulling a box blade than pushing one?

If pushing in reverse and the shear pin gives. The unit will want to rotate suddenly. Will that rotation catch any other parts? or jam it into the back of tractor?

 

[JohnMiller3]

Hi Ken…

I think you have a great idea… as soon as you have the prototype ready… let me know… I’ll be over with my md rear blade and test it out…

…on your TC35… /forums/images/graemlins/blush.gif /forums/images/graemlins/tongue.gif

/forums/images/graemlins/laugh.gif

Actually, I think of those “what-if” idea’s myself… /forums/images/graemlins/smile.gif

Consider this… using a “hydraulic” top link that would act similar to a shock absorber both in tension and compression… /forums/images/graemlins/wink.gif

 

[kensfarm]

Thankyou Nick.. I agree on brainstorming & ideas.. if one person can make a good product.. a team of ideas could make a great product.

"Shear pins are there to prevent further damage, not provide a possible failure point that might cause damage by shearing"

I disagree.. shearpins do provide a failure point.. so no damage can be done to the implement.. it's gearbox.. etc. like a PHD, Plow, Tiller, Rotary Cutter. The shearpin is the engineered failure point.

"I want my top link connection SOLID"

Yes.. definitely.. even w/ the shear pin this top link would be solid.. but depending on the implement & application.. I have seen some threads where TBN'rs are using a chain for the top link to allow the rotary cutter to float like a trim mower. Hmmm.. remove the shear pin.. and you have a floating top link.. now.. how to limit the floating length in either direction.

Even disagreeing ideas.. give ways to more ideas and better solutions. Thankyou Nick! I'll keep brainstorming..

 

[kensfarm]

Tyler..

"more force applied pulling a box blade than pushing one"

I guess it would depend on the boxblade's setup.. blade angles, diggers etc. If the same.. for example..I wouldn't think it would be harder to push a car from behind.. compared to pushing it from the front.. same resistance in either direction.

"If pushing in reverse and the shear pin gives. The unit will want to rotate suddenly. Will that rotation catch any other parts? or jam it into the back of tractor?"

The top link's mid section would slide together.. then stop at a point.. the end result being a shorter top link. The implement would jump some.. but stop before jamming into the back of the tractor. Causing less damage then a collapsed hitch might cause. Thankyou Tyler

 

[kensfarm]

John.. I think that's a good idea in itself.. shock absorbing" top link... w/ adjustable tensioning.. capable of floating.. I wonder if hydralics would give a top link those capabilities.. or would it have to be more of an air shock? The designing part just got tougher. Great idea! Thanks John!

Sounds great.. come on down.. I have lot of rocks.. we wouldn't have far to go to find a testing spot. I was looking for a testing partner.. if you share in the risks.. you get to share in the profits.. or.. we'll just be looking at a broken tractor & or boxblade!

 

[markct]

yea i can see a few problems with this idea, like say ya had an implement lifted up and were driving along, hit a bump and sheared the bolt,well when that thing slammed down to the point where it hit the stop that wouldnt alow it to move any further then ya would have one heck of a shock load and then ya would surely break something, or say ya were driving along transporting an implement and it sheared off on a bump, depending on the implement it could dig in and be like dropping an anchor and send you tumbling over the hood. just a bit of operator common sense is all that is needed to prevent 3pt damage, of course it seems that nowdays everyone with a few acres has a tractor and common sense isnt that common.