View Single Post
  #45   Spotlight this post!  
Unread 31-08-2010, 15:37
AdamHeard's Avatar
AdamHeard AdamHeard is offline
Lead Mentor
FRC #0973 (Greybots)
Team Role: Mentor
 
Join Date: Oct 2004
Rookie Year: 2004
Location: Atascadero
Posts: 5,497
AdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond reputeAdamHeard has a reputation beyond repute
Send a message via AIM to AdamHeard
Re: Winnovation Midwest Coast Drive

Quote:
Originally Posted by RookieWookiez View Post
Our team is currently looking a making new gear boxes similar to yours, I was wondering if u could or anyone eles could help describe to me how they work. I understand the concepts behind the shifting but I don't know what a dog gear does, or even if it's needed. Any help would be wonderful, thanks.
I'd download the CAD models that AndyMark has posted on their site.

If you examine the models, you can see that the output shaft has a pair of gears on it, on bearings so that they are not torsionally attached to the shaft. Between these two gears is the "dog" that is torsionally attached via a hex shaped shaft. The dog has a tooth/shape pattern on it which matches a similar pattern in each gear. When the dog is pushed against a gear, they interlock, and that gear is then able to transfer torque to the shaft. The two different gears are different sizes with different ratios, so by changing which is engaged you change your reduction (and neutral would be the space between).