Oscillating Reed Switch Pulse Motor.

[OrionLightShip]

24 gauge: 0.0201 (0.51054 Ohms per thousand feet) 25.67 84.1976 3.5 (0.577 amps) 68 kHz (11.5 lbs per thousand feet):


Maybe it would help to increase the coil wire thickness from 26 to 24 gauge? The gold wire in the Radio Shack assortment package.

larger the gauge.....smaller the wire diameter....higher the resistance

[Allen Burgess]

24 gauge: 0.0201 (0.51054 Ohms per thousand feet) 25.67 84.1976 3.5 (0.577 amps) 68 kHz (11.5 lbs per thousand feet):


Maybe it would help to increase the coil wire thickness from 26 to 24 gauge? The gold wire in the Radio Shack assortment package.

[Allen Burgess]

Where did yu guys find the ceramic bearings for this?

Dave

@Turion,

Please look at comment #13 on page 1:

Boca Bearing Company :: Ceramic Bearing Specialists

Popular Searches | Boca Bearings

[Turion]

Where did yu guys find the ceramic bearings for this?

Dave

[OrionLightShip]

@Matthew Jones,

I'd love to see the "Reed oscillator" on a scope! Thanks for solving the coil Ohms for #26 ga magnet wire to match the .5 amp Reed switch current rating problem. You gained my complete confidence with that important amount of math, and put the replication on solid ground. I couldn't help with that critical information. I'm sure my coil was over wrapped, because it burned too many switches out!

I think that the reason you survived with so little wire, Allen, is due to impedance at frequency. If you survive the initial inrush current, the inductive reactance adds to the dc resistance value which gives the total impedance.

[Allen Burgess]

Scope.

@Matthew Jones,

I'd love to see the "Reed oscillator" on a scope! Thanks for solving the coil Ohms for #26 ga magnet wire to match the .5 amp Reed switch current rating problem. You gained my complete confidence with that important amount of math, and put the replication on solid ground. I couldn't help with that critical information. I'm sure my coil was wrongly wrapped, because it burned too many switches out!

[Matthew Jones]

I disconnected the positive battery lead and tried to coonect over to the negative, but it died. It needs the battery in the circuit, even though there was no apparent current draw at top speed.

Not doubting or anything but if thats whats happening the inductive spike going back to source averaging the current coming into the coils creates a situation on an amp meter that makes it appear there is no current draw. This would be more relative do to the low impedance coil and their tendency to have near source voltage transient behavior. Thats why you need the battery still.
Its taking power out and putting power back so fast the meter cannot tell. At that point you need a scope.

Matt

[Matthew Jones]

Ok, think I'm starting to get the idea.....
It works like an inline solenoid relay connected to an induction coil that opens the contacts momentarily when current flows, then closes them again. This one just uses two fields like a spring in a way that I will have to accept without actually understanding.

I have seen someone run these type magnets up to 70,000 with pancake coils and a hall sensor and no explosion....he was nuts though....no shield at all.

I am not shielding it either. Go balls out or don't go at all.

Matt

[OrionLightShip]

@Matthew Jones,

There's no where near an entire spool of #26 ga. on the thread bobbin. Don't excced the .5 amperage with too much wire. The thread bobbin has a thick core. Let me point out that the coil field seperates the contacts nearly instantly after they close from the PM field, severly limiting the on time. The coil is wound bifilar and series connected. It starts on the bottom and ends on the top. The positive of the battery goes to one side of the Reed switch; The other side goes to the top wire of the coil. The bottom coil wire goes to the negative of the battery. The important feature of this build is the position of the Reed switch directly on the coil winding. I found a picture of the actual thread bobbin: There's only a few layers of thread on the bobbin in the picture, the rest is the thick core.

Ok, think I'm starting to get the idea.....
It works like an inline solenoid relay connected to an induction coil that opens the contacts momentarily when current flows, then closes them again. This one just uses two fields like a spring in a way that I will have to accept without actually understanding.

I have seen someone run these type magnets up to 70,000 with pancake coils and a hall sensor and no explosion....he was nuts though....no shield at all.

[Allen Burgess]

Current draw.

I disconnected the positive battery lead and tried to coonect over to the negative, but it died. It needs the battery in the circuit, even though there was no apparent current draw at top speed.

[Matthew Jones]

My analog milli-amp meter needle was resting solidly on the peg.

I wasn't reading any draw of current?

[Allen Burgess]

Laser Tach.

I went up through the bottom with a Laser Tach, perched over a counter top. It climbed in speed to around 25 thousand R.P.M's at a regular rate for maybe half a minute; Then it hyper accelerated to nearly 50 thousand R.P.M in a few seconds. John Bedini surmised the rotor "skipped" a turn. My analog milli-amp meter needle was resting solidly on the peg.

It may be a mistake to try and save a few dollars on a magnet if a flaw shows up at 800Hrz!

[Matthew Jones]

Did you ever put a tach on it to see how fast it was going, or look at the frequency of switching, anything like that?

Matt

[Allen Burgess]

Oscillation.

I built this motor as simply as possible just to test the bearings. I started "fishing" for a sweet spot with the Reed switch when I got a sudden burst of speed touching the base of the coil with the switch. The theory came later. This design is capable of "run away" self powering that's really awesome. I had no idea what I was in for!

[Matthew Jones]

Never mind what I posted I get it. Because the coil comes on when the magnet lines up it mitigates the magnetic field from the PM. You have power coming in for 2 directions switched via the reed then each side of the coil is grounded, so it does a push pull.

Sorry I am blond.

Matt