[Yahya A.Sharif (OP)]

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The idea is four neodymium magnets at balance due to equality in attraction and repel force when the air compressor #1 moves from right to left it rotates the wheel #3 and the wheel vibrates the magnet it is contacted to causing imbalance to  the system of the magnets and causing the magnets # 6 to move from side to side as long as the magnet vibrates

[Yahya A.Sharif (OP)]

The vibration could be slowly with 2 mm length giving motion from side to side for magnets #6 up to 10 cm length  or perhaps longer for lager magnets by that I could convert the short distance of the air compressor (or weight) to long distance motion just like my clockwork   https://www.thenakedscientists.com/forum/index.php?topic=74333.0   
But this is cheaper and more practical.

[Yahya A.Sharif (OP)]

even though it stores small amount of energy it could be very cheap:
https://www.amazon.com/Powerful-Neodymium-Magnets-Rare-Earth-Magnet/dp/B076RBS92F/ref=sr_1_7?crid=2NAMPKCK4ESKC&keywords=neodymium+magnets&qid=1553700561&s=gateway&sprefix=neod%2Caps%2C490&sr=8-7
Neodymium magnets are very strong they can give high force:
https://en.wikipedia.org/wiki/Rare-earth_magnet

[Yahya A.Sharif (OP)]

For the 2 mm and the 10 cm the ratio would be 1:50 but I could use a gearbox of 1:10 on the wheel and another one of 1:10 on the generator giving a total ratio of 1:5000 if the generator is 60 Hz and the weight height is 4 meters ( I could use an inclined plane) the machine could last for 9 minutes and as the machine cheap I could multiply the numbers of this machine and obtain more discharge time.

[Yahya A.Sharif (OP)]

What do you think?

[Bored chemist]

It's going to be cheaper to use springs to store energy than Nd magnets.

[syhprum]

Of all the non chemical ways of storing energy using gravity such as the mill pond is by far the oldest with modern variations such pumped hydro storage, then came the compression of metals a very expensive but often convenient method of storing a small amount and the compression of gasses when a natural reservoir is available.
The latest method is to store it in a kinetic manner with a flywheel which is useful when a high peak power is required but it suffers from the problem that it decays fairly rapidly.
Energy can also be stored as heat most conveniently used to cause a phase change but the overall in /out ratio is rather low.
The idea of digging large holes to store energy by gravity is rather senseless when hills and valleys are available and mass in the form of water is very cheap also substituting magnets for gravity that cost nothing does not make sense.