Why the Newman torque is low and what to do about it

[Michelinho]

The Newman Motor is a high efficency, high torque and low rpm motor, that is what Joseph Newman came up with. The replications you see on the internet are mostly built much smaller and with many differences from the original design.

To get torque, you have to have a big and heavy magnetic rotor. That needs a big coil as it must cover a big part of the rotor's magnetic field. A big coil will need either high voltage/low current or low voltage/high current to build a strong enough magnetic field to move the big rotor. Newman went with the first as it is more energy efficient as the coil(s) gets cooler than the ambient temperature instead of getting hot from the high current and the utility bills you on current, not voltage use. The commutator you use will tune the motor for whatever need.

The commutator can be of 3 types as Jean Louis Naudin explains on his site: depending on the design the commutator it can make the Newman's device run as a motor, a motor/generator or as a generator. Most of the commutator reproductions you will find on the net are the first type "motor" and people don't see OU or get the unit to self-run. I wonder why? 

Check his latest motor, the 400 lb one, it runs at about 60-80 rpm on a 162v input (18 x 9v batteries) and it does recharge the batteries (more or less) with a mechanical commutator. What Newman's doesn't tell is that he is probably stepping up that voltage like on his old 7,000 lb motor that runs on nearly 2 kv after the step up. The big one has 55 miles of magnet wire and the magnetic rotor weight around a thousand pounds.

So to recap, I don't think you will ever see a razor or a drill with a Newman motor but for a lathe or milling it would be perfect. If you want torque, the Newman machine is expensive to build but highly reliable and cheap to run and with low maintenance.

Take care,

Michel

[khabe]

The Newman Motor is a high efficency, high torque and low rpm motor, that is what Joseph Newman came up with. The replications you see on the internet are mostly built much smaller and with many differences from the original design.

Hereby some basises about el. motors,
http://www.stmicroelectronics.com/stonline/products/support/motor/tutorial/motor.swf

regards,
khabe

[seekingknowledge]

The commutator can be of 3 types as Jean Louis Naudin explains on his site: depending on the design the commutator it can make the Newman's device run as a motor, a motor/generator or as a generator. Most of the commutator reproductions you will find on the net are the first type "motor" and people don't see OU or get the unit to self-run. I wonder why? 

Ive seen a a couple of diagrams on the net of his commutators (just google it lol) but not sure which one is generator commutator if either , your commutator is simler , one had many off on segments and another had the same but with shorting segments, does your commutator have shorting segments?

Is your commutator for motor/generator or just generator? i dont really care for the motor commutator im more interested in electrical output so mainly the generator commutator do you know for sure which one this is? it would be a huge help, and very nice work by the way i envy.

[Michelinho]

The commutator can be of 3 kinds:

Motor commutator: Firing once every turn. The tape on the shaft is a perfect exemple, the reed switch also. Little recovery of bemf is available.

Motor commutator 2: Firing once every half turn with polarity inversion for next half turn. The first Jean Louis Naudin commutator. More torque and slightly higher rotational speed. Little recovery of bemf is available.

Motor/generator: Firing once every half turn with polarity inversion for next half turn (multi-segments commutator) . The last of Jean Louis Naudin commutator. More torque and slightly higher rotational speed. High recovery of bemf is available caused by the rapid on/off loading and unloading of the coil. The Joseph Newman commutator is of this design with a short section to permit the use of higher input voltage JLN did not test with the "short" segments. The firing sequence is: Firing-Blank-Short-blank-Firing. It is the one I use in my 2nd prototype.* (The second blank section is not on Newman's paper but is obvious to prevent an input short circuit when the contacts are a little misaligned and it also permits a larger brush.)

Generator commutator: similar to the Motor commutator but in this case the motor is turned by an external force to produce ac voltage. One phase output only.

The firing sequence of my last commutator: "Firing-Blank-Short-blank-Firing" works in this way: Ramp up of the coil-- on blank the coil discharge (The coil is in this case acts like a capacitor)--On short, the coils stabilize to a neutral potential--On blanks it gets ready to get ramped up again eliminating the possibility of a short of the "firing" and "short" contacts. A bonus with this coil is that it permits the use of very high voltage to drive the coil ( in excess of 300 volts)

Hope this helps,

Michel


The picture is the test of a commutator "Motor/generator commutator" as used by Jean Louis Naudin in his last tests of the motor showing "OU".

[Michelinho]

Top view of the "Motor/generator commutator".