Multiple Gears

[ruggerodk]

Does anyone know the right technical term for this kind of gear?
At "Kinematic Models For Design" it says "Multiple Gears".....
regards
ruggero ;-)

[path_finder]

Dear ruggerodk,
The same kind of mechanism (see the animation in this old topic:http://www.besslerwheel.com/forum/viewt ... 3494#53494 is named a reciprocator.
A Java applet is available here:http://demonstrations.wolfram.com/Ellip ... iprocator/
But the mechanism in your drawing seems to be much more closer with 'Oldham joint'
or 'Double Slider Ellipsograph of Leonardo da Vinci'
or 'tripod joint'
Several videos are on YouTube, like this one: http://www.youtube.com/watch?v=9N6QXJSppTY
An excellent animation is shown here: http://www.mekanizmalar.com/diskandfork60.html
This concept allows to get an excentered axis, but the worst point is the retroaction linkage needed.

For those interested by all kind of mechanisms, there is a fantastic web site here: http://www.mekanizmalar.com/

[ruggerodk]

ohhh, thank you so very much Path_Finder.
These are som every interesting links ;-)

Can you please explain what you mean by: "...but the worst point is the retroaction linkage needed." - I'm not sure I understand what this is ;-(

regards
ruggero ;-)

[path_finder]

Dear ruggerodk,
As you can see in the video the primemover is the hand of the manipulator, acting on the crank.
If you want to get a gravity machine, you must have a mechanism collecting the rotational motion of the main wheel and transferring the torque to the axle of the tripod.
This retroaction will always be not sufficient for acting the crank and less more for accelerating (because it is in that state just a closed loop system).
Connecting back the rear wheel and the pedalier with a belt, leaving the standard chain in place, the bike will never run by itself: you need an extra source of energy. You can read everything about this controversial discussion through the excellent pots of Fletcher and greendoor (almost, I apologize to all other contributors).
As explained many times, a primemover, alone, cannot be sufficient.
IMHO the answer at this important question is a combination of the gravity (vertical force) and the centrifugal energy. But who knows?

[murilo]

About the sent link:

http://www.mekanizmalar.com/diskandfork60.html

I guess that this mechanism would deserve some study under buoyancy state, with water level applied at 4 to 8 hours.

This means obviously water + gravity... or two 'conservative' stuffs.

Best! Care!
Muliro