Shaft for one-way clutch

[i8angus]

Hi all,

I was woundering if you guys might be able to give me some advice regarding a shaft I am designing. The overall shaft length is only 4 1/2" and it will have a 1 1/2" long section with a 30mm OD and then step down to a 17mm OD with a spline at the end.

The 30mm OD section will have the rollers of a one-way clutch driving directly on the shaft and will require a surface hardness of 58 HRC. The spline would have a floating sprocket captured with retaining rings so it would require some hardness... The shaft would also be hollowed out to save weight.

I don't have experiance in shaft design and I was just woundering how you would go about designing a shaft like this. Would you case harden to 58 HRC in the area of the clutch only? Would you do the whole shaft? Would it warp like crazy if its hollow?

Thanks the advice,

John

 

[Heckler]

Some things you might want to look at based on your input parameters: stationary loads, bending stresses, torsional stresses, axial stresses, and prinicpal stresses. Depending on the speed of the shaft you might want to look at dynamics and balancing.

So you have established the outside diameters and based on the static loading you can calculate what Inside Diameter.

We have a gun drill that we hollow shafts out all the time and they do warp a little but that's usually the first or second process....we centerless grind to final dimensions all critical areas on our shafts. The types of materials we use are H11 and other tool steels, 4140 & 8620 steels. We also induction harden critical areas like bearing surfaces or sprag clutch surfaces.

Here are some commerical specs:

ANSI B106.1M Design of Transmission Shafting
ANSI B92.1 Involute Splines

Heckler
Sr. Mechanical Engineer
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[i8angus]

Thanks Heckler!

Dumb question #2

The one-way bearing requires that I have a 58 HRC 30mm OD surface for it to run on... The 17mm splined part of the shaft may not need to be that hard but is it more economical to spec a surface hardness of 58 HRC for the entire shaft surface rather than have say a 35-40 HRC spline and a 58-60 HRC bearing surface?

Thanks again Heckler,

John

 

[unclesyd]

Agree with Heckler in his choice of materials for the small shaft. We used both H11 and 4140 numerous small shafts with H11 being the material of choice if any temperature is involved. I would like to add one that we use for smaller precision shafts, the material is D2 Tool Steel.

 

[i8angus]

Thanks Unclesyd,

Sounds like 4140 might be a good choice as there are no high temperatures involved and I assume H11 would come with a higher price.

John