Clocking gear teeth with an asymmetrical feature
Clocking gear teeth with an asymmetrical feature
(OP)
I need a little help here.
How would I go about ensuring that the flat on the internal D-hole is oriented to the gear tooth pattern? We are referencing an AGMA spec to dictate the geometry. I don't know the number of the spec. My assumption is that the tooth geometry--and tolerancing--is dictated by the spec and the spec probably doesn't use profile to tolerance the tooth geometry. If we were to define a tooth with basic dimensions then we could get simultaneous requirements to apply but we'd rather have the spec define it. Any ideas?
Before you guys slap me around too badly, I have no real experience with gears so have a little mercy on me.
Thanks,
How would I go about ensuring that the flat on the internal D-hole is oriented to the gear tooth pattern? We are referencing an AGMA spec to dictate the geometry. I don't know the number of the spec. My assumption is that the tooth geometry--and tolerancing--is dictated by the spec and the spec probably doesn't use profile to tolerance the tooth geometry. If we were to define a tooth with basic dimensions then we could get simultaneous requirements to apply but we'd rather have the spec define it. Any ideas?
Before you guys slap me around too badly, I have no real experience with gears so have a little mercy on me.
Thanks,
John Acosta, GDTP S-0731
Engineering Technician
Inventor 2013
Mastercam X6
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II





RE: Clocking gear teeth with an asymmetrical feature
This is what I was able to find in Genium Manual:
RE: Clocking gear teeth with an asymmetrical feature
Frank
RE: Clocking gear teeth with an asymmetrical feature
John Acosta, GDTP S-0731
Engineering Technician
Inventor 2013
Mastercam X6
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II
RE: Clocking gear teeth with an asymmetrical feature
RE: Clocking gear teeth with an asymmetrical feature
CH,
I agree a tooth can be used as a datum, I do not think it is generally, functionally speaking, a primary datum.
Frank
RE: Clocking gear teeth with an asymmetrical feature
Please see my sketch as "intentionally incomplete"
I am not setting primary datum, just giving example what the datum may be.
RE: Clocking gear teeth with an asymmetrical feature
I would tend to do just what powerhound has done, in the OP, and added CH's dim accross a tooth and use a position of the tooth at pitch line. Face(I assume) is primary, bore is secondary and flat is tertiary. I see this as a functional definition (assuming I have correctly read how it functions). Bore could be primary if face is not fumctional :)
Frank
RE: Clocking gear teeth with an asymmetrical feature
I know that simultaneous requirements is not the only way to control things, it is just one easy way that I can think of. Your example is another way.
John Acosta, GDTP S-0731
Engineering Technician
Inventor 2013
Mastercam X6
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II
RE: Clocking gear teeth with an asymmetrical feature
It is really nice to dimension everything from the same datum framework, and, as a bonus, get everything glued together by simultaneous requirement without extra effort.
But sometimes you have to make a choice to control one feature WRT other.
There was a thread on this forum about practical ways to clock gears:
http://www.eng-tips.com/viewthread.cfm?qid=111643
The posters generally agreed that it is better to cut teeth first.
So, using tooth as a datum was not exactly part of my evil plan.
RE: Clocking gear teeth with an asymmetrical feature
RE: Clocking gear teeth with an asymmetrical feature
I agree with pmarc, that was also my point about the proposed Genium solution, it is not really up yo date.
RE: Clocking gear teeth with an asymmetrical feature
When you make tooth a datum, you imply that said tooth is somehow more important than others.
RE: Clocking gear teeth with an asymmetrical feature
RE: Clocking gear teeth with an asymmetrical feature
RE: Clocking gear teeth with an asymmetrical feature