DIN 5482 Splines - Is there a resource to determine lash?

[TDKPE]

I've got existing spline connections which I am told have excessive lash. What I can't seem to figure out is if lash is somehow included in the DIN standard through tooth thickness and so on, or if the final fit is up to the original engineer to determine and specify through those same DIN parameters. The shaft is a commercial product, but the gear is strictly custom.

I'm afraid my knowledge of splines is light, so any insight into this issue would be most helpful.

 

[spigor]

DIN 5482 specifies three types of fit - clearance (default), tight and press fit (if memory serves well) - as well as the measuring data needed to check the parts for each fit. The designer needs to specify the type of fit and the parts are made and checked to it.

 

[RolMec]

Could you pls. tell where that excessive lash occurs, between the teeth of the gearing or elsewhere?
DIN 5480 defines 3 types of centering, thats
- on the flanks
- on inner dia
- on outer dia
With the second and third, a lash or play between the gearflanks is functionally necessary.
Any lash or play within the spline connection is then a function of the above choice, through the manuf. dimensions.

Regards
R

Roland Heilmann

 

[TDKPE]

I can't classify the lash as 'excessive' yet. Just that there is lash, which is expected as this is not an interference fit (hand assembled in the field) and new shaft/gear connections exceed the manufacturer's lash specification using their proscribed measurement techniques (again, intended for field measurement). This is with the gear and shaft removed from the machine, so only the spline connection is being measured with no gear tooth interaction or interference.

We've sent some samples to a local gear cutter, along with the pin measurements and other critical dims from the DIN standard which I just purchased. We'll see what he comes up with, and I'll report back when I get it.