MOCpages : Share your LEGO® creations
LEGO models my own creation MOCpages toys shop 4-Speed Sequential GearboxTechnic
Welcome to the world's greatest LEGO fan community!
Explore cool creations, share your own, and have lots of fun together.  ~  It's all free!
4-Speed Sequential Gearbox
A 4-speed gearbox, where the changes are made sequentially from 1 to 4.
About this creation
Having recently read-up on how automatic and sequential gearboxes work (as you do!). I thought it would be quite easy to implement a simple sequential-shift in Lego using rotating cams to move the gear-selectors.





The gearbox itself is pretty standard.



The two dog-rings are moved by individual selectors (in red), these are moved using short 2L liftarms, shown in grey.



A rare sight: a Lego cam being used as a cam!





The 16z gears keep all four cams aligned so that they rotate together and push the relevent gear selectors at the right moment.





A crank and handle on the top works the gear selection.



Rotating the crank by a quarter turn each time changes the gear. Clockwise goes up a gear, anti-clockwise goes down. I have not yet added a push/pull mechanism to replicate the shifting, but this part could me motorised. For example, a Mindstorms motor programmed to make quarter-turn increments each time a change is called for.












Comments

  April 23, 2013
Just curious... did you make any progress in making the gearbiox smaller? WIth only two cam-shafts?
 I like it 
  August 22, 2011
Wow! this is great! Using cams is a brilliant idea. I liked Sheepo's 7+R gearbox (I assume you've seen this)but It uses a lot of rubber bands that never worked reliably for me. The cams avoid that. I can't wait to try this design, but I am a few cams short. I've also got a idea on how to add another dog ring to the gearbox using a similar method. Could you post a few pictures of the position of the cams in each gear setting? I want to be sure I know the order they turn in. Thanks, and good work.
  March 8, 2011
A pretty fresh thought in the Lego gearbox world... or at least, I haven't seen anything similar. The one problem is that it's not a perfect R/C-Solution, as there's no stop upon a gear shift, correct? Otherwise, a pretty cool concept, and so far the most compact solution I'm aware of that utilizes multiple gear rings with a single shift motor. Keep up the great work!
 I made it 
  February 20, 2011
Quoting Sander van Kreijl Wow, a small step for you, but a great step for AFOL-kind! I wonder if this could be upgrade to a six speed box, by using the smalle belt wheels with six holes. Great work, gear boxes just keep me puzzled, mostly on how to make a solid gear shifting device. This way it is pretty easy. Only drawback seems to be the amount of space it takes.
I'm afraid a six-speed box using this method would need more than just six-holed cams, the problem is the shape has to be just right. The cam needs to be able to move the lever forwards, backwards and (the difficult bit!) back to the centre-position. I will have a go at re-working the gearbox to save space, I have an idea using only two cam-shafts that might be smaller...
 I like it 
  February 20, 2011
Wow, a small step for you, but a great step for AFOL-kind! I wonder if this could be upgrade to a six speed box, by using the smalle belt wheels with six holes. Great work, gear boxes just keep me puzzled, mostly on how to make a solid gear shifting device. This way it is pretty easy. Only drawback seems to be the amount of space it takes.
 
By Jeeves Lego
Add to my favorite builders

8
people like this. See who.

4,703 visitors
5 comments
Added February 19, 2011
 


LEGO models my own creation MOCpages toys shop 4-Speed Sequential GearboxTechnic


You Your home page | LEGO creations | Favorite builders
Activity Activity | Comments | Creations
Explore Explore | Recent | Groups
MOCpages is an unofficial, fan-created website. LEGO® and the brick configuration are property of The LEGO Group, which does not sponsor, own, or endorse this site.
©2002-2014 Sean Kenney Design Inc | Privacy policy | Terms of use