An Inexpensive High-Voltage Relay switch?

[kmarinas86]

As an alternative to constructing my own relay switch (which I predict will cost around $20), I want to know if there is a device on the market less than $20 that will handle these needs:

1) Deal with input voltages in up to 400 volts.
2) Deal with the same kind of voltage and currents sparks that an insulated piece of 28AWG wire can handle.
3) To be able to switch the coil polarity every 180 degrees with some time in between in the off position (at least 20 degrees of arc).

If these needs cannot be met, I have the following plan.

As a base, I will use binded u-shaped stacks of lego blocks to house two pairs of bearings, one on each side, fastened using twist ties (i.e. no flammable or conductive parts).

The bearings will house a shaft, fastened by nuts.

Between the two bearings, I will have attached square nuts that will support two anti-parallel stacks of permanent magnets, creating four magnetic poles in four seperate quadrants. The purpose of the arrangement of the permanent magnet is to rotate 90 degree everytime a larger permanent magnet rotates 180 degrees. This will allow me to create a commutator where all of the input or output wires are fixed in place.

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NS
NS
NS
SN
SN
SN

Attached to these poles will be wafer-thin ferromagnetic plates I will have glued to a flat ring disk made of non-conductive plastic material.

To the plastic material, I will have glued eight curved pieces of copper, four per two sides of the flat disk.

The first four pieces of copper will consist of two opposite-sided pairs at the 0 and 180 degree positions respectively, and they will be connected directly to each other through a 28AWG wire.

The second four pieces of copper will consist of two pairs each consisting of one at the 90 degree position and one at the 270 degree position on opposite sides.

Magnet position:

0 to 60 degrees

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1-2
| |
4-3

90 to 150 degrees

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1 3
|x|
4 2

180 to 240 degrees

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1-2
| |
4-3

270 to 330 degrees

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1 3
|x|
4 2

I already have plenty of ferrite magnets.

The lego pieces should not cost me more $10 (including shipping).

The nuts and pvc pipe should not cost more tham $5.

I can just glue a plastic disk (such as from a new CD pack) directly.

The copper curved pieces (8 of them) could be made out of foil to keep costs down. Or I could use a cheaper plastic alternative and just wrap wire around that (for my Newman motor project)

[kmarinas86]

I have updated my plans for a reed relay switch that will be able to reverse the polarity of battery pack across the coil.

Instead of legos, I will use two left over battery holders and remove their metal bits (e.g. springs).

Instead of a pvc pipe or a threaded steel bar, I am going to use a 2-inch long threaded bolt.

Instead of magnets arranged anti-parallel with each other, I will construct a conventional x-shaped quadrupole rotor.