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Unread 08-04-2010, 11:21
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Re: Gearbox Maximum Torque

Quote:
Originally Posted by Joe Johnson View Post

Bill Beatty and I agree (I can't find the thread but trust me, he does) on this point -- a simple beam bending stress calculation is a more appropriate estimate for FIRST gear teeth.

Joe J.

As Joe is eluding to, the cycle count and service life are quite low for FRC robots.
Last year 217 saw around 100 matches. At 2:15 minutes per match, it is less than 4 hours of runtime. Even at the 4500 rpm (cim speed) this is only 10^6 cycles. This is relatively low in terms of most design lifes, but within the fatigue regime of design. Really though the initial stage is seeing the lower torques. With a 50:1 or more, you are now down to 2x10^4 cycles. This is down within the infant death for most powertrain systems.
Thus I tend to agree with Dr. Joe that design so that the teeth do not yield, and you should be good to go.

Hmmm. maybe a simple set of equations would be good for this and helpful to the community.

IKE