As a newbie in physics I imagine this device and I would like to know why it can't increase its energy.
Note I study the sum of energy during one second (or less) after set friction ON.
I imagine 7 gears in rotation around blue axis in clockwise. Each gear has a mass $m$. In the same time, gears are turning at $w2$ around themselves. One clockwise next one counterclockwise like gears. But like I have 7 gears (odd number), 2 gears rotate in the same direction (2 red gears at bottom). I know 2 red gears at bottom can't turn like gears but I don't want gears but friction, it's possible to imagine a part of gear with rough surface only and study the device during a little while. So, between these gears I would like only friction. This friction give heating and forces $F1$ and $F2$, others gears give forces too, $F3$, $F4$ etc. I try to draw all forces but maybe I'm wrong.
G1 can have mass or not
To draw forces, I'm starting from forces F1 and F2 and after I draw forces at right and at left in the same time, until I arrive at G1 (I'm not sure).
I define, $F = | F_1 |$, $r$ the radius of a gear, $t$ the time.
1/ G1 has mass. I have a counterclockwise torque on blue axis, the energy from this torque is $E_1=-2Frtw_1$. I have a torque on gear G1, the energy is $E_2=+2Frtw_2$. $E_1 + E_2 != 0$.
2/ G1 don't have mass. The same conclusion than 1/
3/ With 2 red disks only (not others gears), there is the same torque on disk, a torque on blue axis, but there is heating too. The heating seems to be an extra energy if I compare to 1/ and 2/. The work from heating is $E_3=2Frt(w_1-w_2)$, here the sum of $E_1 + E_2 +E_3 = 0$
So, it seems in cases 1/ or 2/ the sum of energy is not constant.
The cycle is:
- Friction is OFF. I launch gears at $w1$ and $w2$ without friction between red/red gears, this step need the energy $E$.
- I set friction ON between red/red gears
- I count all energies (heating too), $E$ must be constant. I'm interesting about the transcient analysis when there is friction between red/red gears. From time $t=0$ to $t=t_x$, with $t_x$ very small.
How $E$ could be constant?
I need to press 2 red gears at bottom for have friction, but I don't drawn these forces.
I guess no friction elsewhere than red/red gears surface.
I don't believe in perpetuum mobile but I imagine devices, and like puzzles to resolve, I try to understand how the sum of energy is conserved, like that I learn physics in the same time. It's like a game for me.