prop pitch motors (curtiss Wright 1944)
Can anybody help with a circut diagram for the curtiss wright 1944 motor
or any sugestions how to reduce the currant drawn. many thanks
Prop Pitch Motors
Wow...I have talked to some old timers who used them as rotors.
While I cannot help with your rquest these guys have a wealth of information on vintage aircraft. The CAF library / research department might be able to help.
You might also try the Smithsonsian AIr and Space Msueum. I'm sure the museum restoration experts would know where to get such information.
President - Shade Tree Mechanics-Rickety Welding & Let the Smoke Out Electronics Co.
It's a heavy-duty motor. Moving those prop blades requires some torque.
If you can access the ARRL periodical archives, there's some circuits there. Typically, they show a 24V @10 Amp transformer and FW bridge rectifier. There is mention of quite a bit of RF noise when the motor is running, but bypassing the power connections using capacitors within the motor housing is offered as a solution.
"It's a beautiful day in this neighborhood..."
If you want to reduce the current you generally reduce the load. Since most prop pitch motors have tons of torque, it would help to know what your turning with it, and of course, the model number, gearing changes, how you have adapted it, and so forth. My first guess would be that it is a 48v motor and your running it on 24v or 12v.
This guy is "Mr. Prop Pitch", I'm sure he can help you out via email:
I used to have a prop pitch motor from a B-25, it could turn the whole tower. There were those who used a prop pitch motor from a B-29 and it could turn the whole house!
The main problem that I had was to get the selsyn motors for the direction indicator working properly.
Originally Posted by K9STH
I was always wondering about that. Did they have to run another whole five slip rings to get the selsyn data back, or were they able to somehow multiplex that on the motor drive slip rings?
"The more you know, the less you don't know."
The selsyns that I had used, if I remember correctly, 3 wires. However, that was over 40 years ago and I eventually went to CDE rotors.
The other issue is the synchros are 26VAC 400 cycle. Typical for aircraft use. Power for the rest was 28VDC ... not 12 or 14V. AGain, typical for aircraft use.
The Handbook years ago had an article showing how to develop the 400 cycle power from two back to back transformers. Long since forgotten where they were.
Telrex used 400 cps selsyns on 60 cps by only energizing them while the rotor was turning. They worked OK. Takes 5 wires but no extra slip rings as the tower selsyn is stationary.
Late 60s QST IIRC Windom wrote up a way around the 400 cycle selsyn problem. I have it here somewhere.
I have a nice post WW2 prop pitch rotor controller here. It appears to use 24 VAC. The xfmr isn't too large. Maybe .3kva. IIRC the old (up to 1972 or so) Orr handbook A.K.A. West Coast Handbook has the diagram.
I'm still not sure a B-29 used an electric prop pitch at at all.
On 7/28/45 a B-25 engine and landing gear tore right through my current work space and landed on the roof of the building across 33rd st. If one knows where to look the repairs to the building are obvious.
Last edited by W2VW; 09-21-2009 at 04:25 PM.