Permanent magnet pendulum motor

[wdford]

I have developed a simplified conceptual plan for an over-unity device, which derives its driving forces from a pair of large permanent magnets (see drawing attached). It breaks no laws of physics, it uses well-known technology and I can see no flaw in the design. I don’t have the means to build a prototype, so I would value the opinions of other knowledgeable people before I embark on the cost of hiring somebody to build one for me. I would also welcome other people to replicate it, or to improve on it if they can.

The device would consist of a simple suspended pendulum, attached at its fulcrum to a horizontal drive shaft. Because of the presence of magnets, the entire pendulum structure should be made of a strong non-magnetic substance (e.g. brass).

On either side of the pendulum-bob would be positioned a very powerful permanent magnet, arranged so that both inward-facing poles have the same polarity. The magnets must be strongly secured to prevent them from moving.

To provide some means for the permanent magnets to “grip” the non-magnetic pendulum-bob, a small electromagnet would need to be firmly attached to the bob, so that its poles face the poles of the two powerful permanent magnets. The electromagnet does not need to be very strong, as the force to move the pendulum (and thus rotate the shaft) comes almost entirely from the two permanent magnets. The electromagnet merely provides something for the permanent magnets to latch on to.

When the electromagnet is energised by a small current, one pole would be “north” and the other pole would be “south”. One pole would thus be strongly attracted by its facing permanent magnet, while the other pole would be strongly repelled by its facing permanent magnet. The permanent magnets cannot move, so the pendulum would thus move through its arc, and in the process, it would rotate the drive-shaft to an equivalent extent.

When the pendulum reaches the safe extent of its arc, a simple mechanical switch reverses the polarity on the electromagnet. The previously-attracting magnet now repels the pendulum strongly, and the previously-repelling magnet now attracts the pendulum strongly. The pendulum thus swings in the opposite direction, and so the process continues indefinitely (and at very high speed).

The drive-shaft can be connected to anything, including a standard alternator. A pair of over-running clutches would be required to ensure that the back-and-forth motion of the pendulum is translated into smooth and continual rotation of the alternator, so as to further conserve the momentum of the shaft, and to produce clean and uniform power.

A pair of bumpers must be inserted to prevent the pendulum from smashing into either of the permanent magnets, and causing damage. Springs can also be positioned to block the pendulum shaft at the extents of its travel, to protect the mechanism from damaging itself, and to conserve and return some of the energy of its interrupted motion. Depending on the springs used, a great deal of energy can be conserved.

Since the force required to swing the pendulum is coming almost entirely from the two permanent magnets, the electricity generated from the alternator should comfortably exceed the trickle of current required to energise the electromagnet, so over-unity should be easily obtained.

The amount of force present in the pendulum would depend on a combination of the strength of the permanent magnets, the length of the pendulum shaft, the size of the springs and the arc-distance travelled by the pendulum.

The design is so simple that I don’t believe it can be patented. I am happy to open-source it, and to share it freely with anybody who helps to iron out any bugs and make a working model.

I would greatly welcome any feedback and suggestions.

[gauschor]

Interesting concept. The first time I read this I wanted to say it will not work... but it needs more consideration...

Why I think it will not work on small scale setup (let's say with a pendulum length of 30cm):
The momentum of the pendulum will be too weak to produce a strong enough rotation of the shaft, the clutch (which converts the pendulum movement into a rotation movement) and the alternator (and also gravity!). It will lose too much energy to keep on swinging. Also I think that the electric current produced by a small setup will be too weak to create a strong enough electromagnet. You definitely need a decent magnetic strength, otherwise the permanent magnets will simply overlay the iron core of the electromagnet - leading further to a reverse of polarity of the electromagnet. Thereby the nearest permanent magnet could attract the iron core, snap to it and stop. Or it doesn't snap to the permanent magnet and instead loses too much of momentum to keep on swinging.

But with a decent sized pendulum it could work better. It would require at least a pendulum with 1 meter in length and a defined weight on the bottom. This could produce enough momentum to rotate the shaft decently and also produce an amperage strong enough for repulsion. But another problem occurs: it is the nature of magnets... which are bitch. A magnets' attraction is not continuous in distance, instead it's somehow exponential. This makes it very hard to adjust the device. A default single swing of the pendulum must at least come close to enough to the magnet so it gets attracted (which must be quite close) - but not snap to it! - and then swing backwards. And at the backward swing it must still have enough momentum to reach the other magnet again. Ok, when it comes close to the first magnet it will get repelled. This way it maybe gets enough momentum back to reach the other side as well.

But let's say it works... how do you induce a current into the electromagnet at the right moment?
On repulsion from the permanent magnet the electromagnet needs to keep its polarity at least for a certain time (say 1-2 seconds) until it's out of reach of the permanent magnet. In this case you need to pulse the e-magnet with direct current. This is possible. But you need some logic... an electric circuit to do this timing.  This complicates the device quite a bit. And which energy source powers this timer? You can't power the timer by the alternator, because right at the moment when the pendulum is closest to the permanent magnet no electric current will be produced! The pendulum is almost at stop at this point. Electricity can only produced while the pendulum is in motion. A capacitor may be a way to hold charge for a while - but as you see it adds up... 

Besides, pendulums are definitely and interesting choice for possible overunity devices^

[wdford]

Good comments!

My drawing is not to scale â€" it’s just to give people the general idea. Obviously some precise drawings would need to be made eventually.

The weight on the pendulum is the most easily adjusted of everything â€" once you have a device set up, you can add small lead weights to the bottom of the shaft until you achieve the required balance by trial and error. On the prototype, you can also add a telescope effect to the pendulum rod itself, perhaps by having the bottom section as a tube sliding over the solid rod of the top section, so as to enable adjustment thereof until you are happy with the dimensions.

Don’t under-estimate the power of modern permanent magnets â€" they are immensely strong over quite a decent distance. However you are right that the strength of the attraction increases as the magnet gets closer. To manage this I propose the use of springs, so that the massive force over the last inch or two can be stored and returned to the system during the repulsion stage of the swing, and not go to waste.

I definitely think the polarity of the electromagnet should be switched mechanically. One simple idea would be to put a pressure switch in each of the bumpers, which are activated by the impact of the pendulum rod itself. Another idea would be a cam mechanism on the fulcrum attachment. If combustion engine valves can be made to open and close 50 times per second with total precision, then these little switches should be a cinch.

I propose that the electric current for the electromagnet be delivered from a battery, as in an automobile. The alternator will charge the battery when it’s able, but the battery will provide smooth current to the electromagnet even when the alternator is faltering. The alternator should produce much more electricity than is needed for the electromagnet, leaving the surplus available for other use. In addition, the “dead” period of the alternator will be very short â€" I foresee this pendulum moving back and forth many times per second - and the alternator will continue to rotate under its own momentum for a split second each time while the pendulum reverses.

[travin69]

wdford:

There is a glaring issue with your design.

"To provide some means for the permanent magnets to “grip” the non-magnetic pendulum-bob, a small electromagnet would need to be firmly attached to the bob, so that its poles face the poles of the two powerful permanent magnets. The electromagnet does not need to be very strong, as the force to move the pendulum (and thus rotate the shaft) comes almost entirely from the two permanent magnets. The electromagnet merely provides something for the permanent magnets to latch on to."

This is how a regular motor already works.  It uses an electromagnet to "lock" itself into a rotating magnetic field (AC motor) or uses brushes and a commutator on the armature windings to create an rotating field to interact with 2 permanent field magnets (DC Motor).  The issue comes in when you place a load on the shaft, the magnets attraction/repulsion have to be able to interact with the electromagnet.  As the load on the shaft goes up, you will need more current in the electromagnet so the field magnets can adequately attach themselves to the electromagnet.  So, your design will not work as drawn (well it will work, just not overunity).

Having said that, your best bet would be to put a permanent magnet in place of the electromagnet and just rotate it 180 degrees at the resonant frequency of the pendulum (like pushing a child in a swing).  Also, take one of the field magnets and turn it 180 degrees so the pendulum magnet can interact via both its poles (repulsion and attraction) on each swing.  You can get a cylinder magnet with a through hole.  Make sure it is magnetized radially vice axially so the poles will line up correctly.

Additionally, you will also need a rachet type drive where the pendulum attaches to the output shaft to covert the linear motion to rotary motion.  These are not known for their efficiency.

To get better field stregnth on the field magnets, place a piece of soft iron on the poles not being used.  This will increase the flux on the poles that are being used for better "reach".

In the end, the pendulum will need to have a swing of less than 6 to 8 inches (and most likely shorter), though it should have some decent strength as the magnets are always aligned for repulsion and attraction, but the timing will be everything.

Hope this helps,

Daniel

[conradelektro]

As Daniel says in his post. The presented pendulum motor is a (unusual) variant of the common "brushed DC electric motor" (see e.g. http://en.wikipedia.org/wiki/Brushed_DC_electric_motor )

The commutator of the brushed DC motor is the "simple mechanical switch reversing the polarity on the electromagnet". One could put a similar commutator on the axis of the pendulum motor.

The gravity assistance when the pendulum swings down (excellerating because of gravity) is cancelled out when the pendulum swings up (slowing down because of gravity).

But I am sure one can get a patent for it. At least one could file a patent and sell the patent application (because few people can distinguish between a "patent application" and a "granted patent").

http://worldwide.espacenet.com/searchResults?NUM=RU2176327&DB=EPODOC&locale=en_EP&ST=number&compact=false

Greetings, Conrad