Beam deflection equation

[rjwoods77]

We did a beam deflection analysis for our jackshaft and I would like to check it against a known beam deflection diagram that you would normally find in an appendix of a materials book. We have three bearings and two loads. The pattern from left to right is:

Load, bearing, bearing, load, bearing.

I have seen books with just loads of configurations but cant find a book or on the net either. We did a singularity function with zero deflection loads at the supports to backward solve for all the other stuff(credit to Matt Prussian). Just would like to have something to check it against.

Also since we have the time to get real thorough we were thinking of solving of the reaction loads as distributed loads since we know the exact bearing widths, sprocket mount widths, etc. Is it really worth going through all the trouble just get more refined curves? I notice most people don't do this but we have a situation where we have to use specific bearings because of space constraints and they meet the load requirements.

[rjwoods77]

We did a beam deflection analysis for our jackshaft and I would like to check it against a known beam deflection diagram that you would normally find in an appendix of a materials book. We have three bearings and two loads. The pattern from left to right is:

Load, bearing, bearing, load, bearing.

I have seen books with just loads of configurations but cant find a book or on the net either. We did a singularity function with zero deflection loads at the supports to backward solve for all the other stuff(credit to Matt Prussian). Just would like to have something to check it against.

Also since we have the time to get real thorough we were thinking of solving of the reaction loads as distributed loads since we know the exact bearing widths, sprocket mount widths, etc. Is it really worth going through all the trouble just get more refined curves? I notice most people don't do this but we have a situation where we have to use specific bearings because of space constraints and they meet the load requirements.

[Jersey Tom]

Just make it out of steel, call it good. That's what we did.

[jsmooz]

Rob - I would suspect that if you are using pillow blocks or any bearings in the housings that the maximum load listed is that of the housing and the bearing can take more load. If that thought is correct there is usually a safety factor on the housing of 3-5 at a minimum. You also got time to build it, run it and see what happens in real life.


Jim

[rjwoods77]

Jim,

The concern was more of shaft deflection than load capability. In order to fix our cars problems I had to move the sprocket and rotor to the outsides of our birdcages. This means adding 5 inches of length to the jackshaft and I am trying to determine if I can get away with just two bearings of if I have to add a third because the span is so long where the clutch resides.
We are limited to a .75" OD so I want to make sure I don't have to do it again. I did find a nice solver to check our hand work against.

http://www.orandsystems.com/

But I would still like to see the standard diagram for my situation. By the way, what did you think of the exhaust vid?

[markocosic]

These?

http://www.cosic.org.uk/MarkoStuff/fs/beam%20deflections.jpg

If the shaft is long/slender enough for teh deflections to be worth considering, treat it as point loadings and it'll be plenty representative.

[J. Vinella]

Marko,

Check your PM.

[markocosic]

Cheers Jack - Dreamweaver Installer removed http://fsae.com/groupee_common/emoticons/icon_redface.gif - the rest is all pretty incomplete/out of date/otherwise not sensitive. http://fsae.com/groupee_common/emoticons/icon_wink.gif