Gear Cutting

[fid]

Afternoon chaps. I'm currently doing a bit of coursework about gear cutting, well trying to...
Does anybody know if Sykes, Sunderland, Maag, and Fellows machine tool companies use different methods for cutting gears, or whether they're literally just companies that have, or still do, make gear cutting machines? It hasn't really been made very clear to us and I can't find alot on the net.
And while we're at it, any advantages and limitations of form cutting and generating would also be mucho useful to me

Cheers
fid

[nonegreen]

fid said:

Afternoon chaps. I'm currently doing a bit of coursework about gear cutting, well trying to... Does anybody know if Sykes, Sunderland, Maag, and Fellows machine tool companies use different methods for cutting gears, or whether they're literally just companies that have, or still do, make gear cutting machines? It hasn't really been made very clear to us and I can't find alot on the net. And while we're at it, any advantages and limitations of form cutting and generating would also be mucho useful to me Cheers fid

Form cutting relies on an involute shaped tool to produce the individual gear teeth. The problem is that depending on the size of the gear the final tooth shape is imperfect and as such the teeth do not roll correctly when meshed. Generation produces a perfect involute (within limits) and therfore gears produced in this way are rolling surfaces when meshed. Hope that helps oh and try googling for gear hobbers then call one of the suppliers and ask them.

[fid]

Thanks Hobbing information is fairly easy to come by to be honest, but nobody seems to do form cutting anymore! I've ordered this little wonder...
www.amazon.co.uk/exec/obidos/ASIN/0852429118/qid=1102951599/ref=sr_8_xs_ap_i1_xgl/202-6119104-8835013
...from Amazon, but it won't be here for a few days and I'll probably find it's actually totally useless! Grr.

Do you know any other methods of generating, other than hobbing? I was thinking broaching but apparently people don't seem to use that much for gears either. Gotta be a mechanical method aswell, can't write about laser cutting, water cutting, or electro discharge or whateveryacallit cutting!

[walking hormone]

Hello,
broaching is generally used for splines due to the aspect ratio of the teeth to the shaft, still fairly popular though. Hobbing is very common as far as I'm aware and in some cases the tooth form has a ground finish to ensure an acurate form.
A hob manufacturer we used to use was Acedes, try looking them up and you may be able to get some info. Another place you could get some info is from a company called klingelnberg who make machines for cuting bevel gears amongst other things.

Cheers

WH

[fid]

Ah, superb! I can see the hobbing problems section on the Acedes site being particularly useful when I get to that part of the assignment. Cheers WH!