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Unread 04-12-2006, 11:32
Jeremiah H Jeremiah H is offline
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Re: pic: Team 948 2-Speed Ball-Shifting Gearbox CAD Drawing

Very interesting, indeed.
I am not familiar with the concept of ball lockup shifting gearboxes, indeed this is the first I have ever seem of them. I am in charge of developing a godd two-speed gearbox for '07, so here are my questions (more will follow after this) Your expertise and help is greatly appreciated.
I understand how the balls are pushed into slots in the gears, but what is it that causes the thus engaged gears to turn the output shaft? In a dog shifter gearbox, the dog is positively engaged on the shaft (still allowed to slide) and so whatever gear the dog is locked into thus turns the shaft. I cannot find any such mechanism in this drawing. Perhaps I am missing something, but I think this is an important consideration.
And, following that, what happens to the gear (with its ball slots) when it is disengaged and must freewheel on the output shaft? My understanding of the design at present leads me to believe that it would bounce and chatter considerably, possibly even locking the entire gearbox up if it doesn't properly disengage.
Just my thoughts, if someone can answer them, I would greatly appreciate it. Thank you in advance. -JH
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