Jack shaft with two curved jaw couplers

[ironknot]

Jack shaft idea, with two curved jaw couplers.



The sprockets are welded to the coupler halves and then sit on brass bushes.

Second and third coupler halves are machined and welded to splined coupler with bearing between.

A another splined coupler to the left for disc/reverse ring and bearing.

Any comments?

[millbilly]

Love - joy couplings Still need to be with in .002 TIR to make them last. Closer to  .000 the better.....                             Total Indicator Reading

Not a high H.P. coupling....

[ironknot]

Here's the specs I've been looking at, they seem ok for a No 42. . . But that's with no tech experience.

http://www.chainanddrives.com.au/GE%20Curved%20Jaw%20Couplings.html

Three power ratings for torque with power in kw listed below.

This make any sence.

[fabr]

Tried it. Will not work. Curved jaw couplers will run at much more misalignment than standard lovejoys BUT the spider will NOT last. The spider will turn to dust. There are pics here somewhere showing the results. The curved jaws HATE the torque oscillations.

[ironknot]

Thanks M-Fab, didn't think it had been tried I'll go searching.

[fabr]

Look here.

http://www.dtsfab.com/index/index.php?topic=3778.0

[ironknot]

Thanks Fabr, that explained a lot.   

[fabr]

It DID seem like a good idea at the time.

[Engineer]

It DID seem like a good idea at the time.

Yes it did.

[fabr]

The numbers seemed to agree too. Nothing trumps real world results tho.

[ironknot]

Not trying to disagree, but is there merit in still using two on the jack shaft, with the rpm reduced from about 7500rpm to (16:52 - 3.25:1) 2300rpm and using bigger (guess) 4'' couplers, might the idea still work.

The couplers I'm looking have an rpm limit around 3000rpm.

Guesing again, but would two act together and have twice the loading like two shock on a swing arm if so, it may increase the shock loading and with a larger coupler increase it further.

Still just an idea, but in a different application with different demands is it worth checking out.

[fabr]

Not needed in my opinion.  Only reason I was interested in it was to reduce shock loads a trans such as the VW 091 would see .I see,and agree,with your point tho. Did you see the use of a giubo instead ? That works well. Very well.

[ironknot]

Guibo - I'll check into into it from what I've seen its a lot thinner and for that matter lighter, excellent idea.

I'm worried about two chains and 30 inch tyres, for that matter the gear box. From what I've read already, and seen the Guibo should give peace of mind without adding to the weight excessively.

Thanks a heap, I read that in your thread and didn't think to look into in properly.

[fabr]

The small giubo takes up almost exactly the same space as the cj lovejoy I used. The giubo has performed flawlessly.