Two-speed gearbox
Two-speed gearbox
(OP)
Hello, I am designing a basic two-speed gearbox (high and Low) and was wondering if anyone new any good references or links in which I can find an exploded view or a general parts list of an existing model. I'm initially thinking of avoiding synchromesh and dogteeth as the gearbox does not need to shift while the vehicle is in motion, the operator will choose high or low before they begin product use. I am hoping that I can get by with spur gears. Any thoughts or advice (or criticism) would be greatly appreciated! Thanks, Ryan.





RE: Two-speed gearbox
Given the slightest familiarity with automobiles, the operator will probably _choose_ to shift on the fly, no matter what you might say in the product manual. If you have ever tried to change gears on a lathe without rotating something, you would do it, too.
A transmission with a sliding spur gear is certain to break off teeth when shifted on the fly. Constant mesh gears and dog clutches are _much_ stronger.
Mike Halloran
Pembroke Pines, FL, USA
RE: Two-speed gearbox
Thanks, Ryan.
RE: Two-speed gearbox
Don't design for what the operator is supposed to do, design for the worst case scenario of what the operator could possibly do.
ie if the operator isn't supposed to shift on the fly, design it so they absolutely can't. If your design could be shifted on the fly, make it strong enough to withstand that possibility.
RE: Two-speed gearbox
For selecting gears there are some factors such as in/out shaft alignments, gear forces, ...
If the transmitted torque or speed is high then use helical gears.
Also note that you must select different bearings for different types of gears.
see : http://www.engineersedge.com/gear_design.htm
And there are gear handbooks to download:
http://www.qtcgears.com/Q410/Q410Cat.htm
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And an interesting collection: http: