Emerson Odd Early 1930s Tripod Ventilation Fan & Motor - First Restoration and Questions

[Liem Nguyen]

I recently bought this Emerson unusual tripod fan and an extra motor from Mr. Russ Huber. A patent for the fan was filed in April 1930 and granted (to Lawrence M. Persons at Emerson) in 1932; so it was most likely made during the early years of 1930s. It's a commercial fan and was designed "for delivering air through a closed conduit" such as an air conduit to a hot-air furnace. The 6-pole phase-shift motor (1100 rpm) runs CCW and the blade was designed to blow air backwards... What're cool about this example is its bullet rear motor cover uniquely made out of brass! (The cover of the extra motor and another example I found on the Internet seem made out of steel).

I cleaned up the fan, replaced the head wires, removed the paint from the bullet rear motor cover and polished the brass underneath. I also replace the blade with a 6-wing brass blade taken from an R&M 12" fan. See how cool the fan looks now! 

As for the extra motor, it can’t start by itself. The Ohm reading of the external reactor coil is about 2.0 while readings of the wires coming out of the motor are as the following:

B1-B2 = OL (these are lines connecting to the wall power)

S1-S2 = OL (these are lines connecting to the reactor coil)

B1-S1 = OL

B1-S2 = 0

B2-S1 = 19.6

B2-S2 = OL

I need your help to make this motor start by itself. Can I use a speed coil from another phase-shift start fan/motor to start the fan? And if yes, what would be your suggestions? Any advice would be greatly appreciated. Thank you All.  

Edited May 18, 2023 by Liem Nguyen
adding details

[Liem Nguyen]

Here's its patent.Patent-US1847666A.pdf

[Russ Huber]

The second non-starting motor was sold as is part of the package sold to Liem. I asked Liem to bring his questions to the forum for help, one of the assets of the forum.

If there is another means to get the motor rolling without the use of the coil, your help would be greatly appreciated.

[Russ Huber]

Would it be possible to gain the phase shift to start the motor using a speed coil from an Emerson 29646 or like coil using only the top wire and high speed tap wire?

[Roger Borg]

On 5/18/2023 at 2:01 PM, Russ Huber said:

Would it be possible to gain the phase shift to start the motor using a speed coil from an Emerson 29646 or like coil using only the top wire and high speed tap wire?

Mine has the attached. Not sure how common they are, but maybe something similar can work for yours.

I've not yet opened my fan up, so this is all I can suggest at this time.

Good luck, yours cleaned up nicely...

[Russ Huber]

[Liem Nguyen]

7 hours ago, Roger Borg said:

Mine has the attached. Not sure how common they are, but maybe something similar can work for yours.

I've not yet opened my fan up, so this is all I can suggest at this time.

Good luck, yours cleaned up nicely...

Thanks Roger. It's a beautiful speed regulator though I'm not sure if it plays a role in starting the motor, or just regulating the input current after the motor already starts. It'd be interesting to see if your example also has the reactor coil on the back of the motor like mine.

[Roger Borg]

11 hours ago, Liem Nguyen said:

Thanks Roger. It's a beautiful speed regulator though I'm not sure if it plays a role in starting the motor, or just regulating the input current after the motor already starts. It'd be interesting to see if your example also has the reactor coil on the back of the motor like mine.

Seller saw this post and graciously saved me some time. Photos from when he had it attached.

Also an approximately 1936 ad most likely c/o mike kearns.

Does this help solve the mystery?

[Russ Huber]

The coil on the back of the fan serves only as a means of phase shift to start the motor. This is similar to the Emerson Cutler Kiln fans with no speed regulation lever protruding from the base, these fans have a phase shift coil in the base to start the motor.

The speed regulator will give the fan speed selection but is not necessary to start the motor.

Edited May 22, 2023 by Russ Huber

[Liem Nguyen]

With the reactor coil seen on the back of the motor, the separate speed regulator most unlikely helps to start the motor. Thank you for sharing the images of your fan. 

I'd also like to have and will search for a similar speed regulator for my fans. Btw, is the rear motor cover of your example brass or steel? 

[George Durbin]

39 minutes ago, Liem Nguyen said:

With the reactor coil seen on the back of the motor, the separate speed regulator most unlikely helps to start the motor. Thank you for sharing the images of your fan. 

I'd also like to have and will search for a similar speed regulator for my fans. Btw, is the rear motor cover of your example brass or steel? 

I have one of those furnace fans but I don't have the regulator...   😞

[Roger Borg]

2 hours ago, Liem Nguyen said:

With the reactor coil seen on the back of the motor, the separate speed regulator most unlikely helps to start the motor. Thank you for sharing the images of your fan. 

I'd also like to have and will search for a similar speed regulator for my fans. Btw, is the rear motor cover of your example brass or steel? 

Unsure, will put a magnet on it in the next day or so...

[Liem Nguyen]

4 hours ago, George Durbin said:

I have one of those furnace fans but I don't have the regulator...   😞

Hi George, Is the rear motor cover of your example brass or steel? 

[Liem Nguyen]

On 5/18/2023 at 12:58 PM, Russ Huber said:

The second non-starting motor was sold as is part of the package sold to Liem. I asked Liem to bring his questions to the forum for help, one of the assets of the forum.

If there is another means to get the motor rolling without the use of the coil, your help would be greatly appreciated.

Hi Russ, the rubber feet arrived today. I put them in and they fit nicely to the tripod holes. They indeed look much better than those I took from the food processor. Thank you so much! Liem

[Russ Huber]

Nice. Did you turn the stator around in the housing to gain the CW blade rotation?

[Liem Nguyen]

12 minutes ago, Russ Huber said:

Nice. Did you turn the stator around in the housing to gain the CW blade rotation?

No I have not. I still have not decided if I would do that (1) or to find a CCW blade (2) or to keep the exact way the fan is supposed to work (3, e.i. to blow backwards).

[Russ Huber]

What is the rotor shaft diameter?

[George Durbin]

On 5/23/2023 at 4:00 PM, Liem Nguyen said:

Hi George, Is the rear motor cover of your example brass or steel? 

I do not know hell I can't even find it at the moment!

[Liem Nguyen]

8 hours ago, Russ Huber said:

What is the rotor shaft diameter?

It’s 3/8 inches. 

[Liem Nguyen]

47 minutes ago, George Durbin said:

I do not know hell I can't even find it at the moment!

I guess that means you have too many fans LOL. Hope you will find it.

[Russ Huber]

30 minutes ago, Liem Nguyen said:

It’s 3/8 inches. 

That makes it more difficult to find a 6 wing CCW rotation blade. Stamp Steel Westinghouse CCW rotation brass blades are more common but fit a 5/16" shaft. 

You could look into how involved it is to turn your stator around in the housing along with the stator wiring for CW rotation. 

Or, you could "carefully" re-pitch the wings on the blade you have. Using a channel lock pliers with the jaws wrapped with something soft and taped, you grab each wing one by one down by the hub spider finger and bend it opposite pitch. You would have to get a small 12" section of 3/8" shaft to put the blade on and clamp the 3/8" rod in a table vice to secure the hub to do the bending. You will then need a strobe to tweak all the blade wings into sync.

Or, you can live with what you have, or, maybe someone has a better idea?

[Liem Nguyen]

18 minutes ago, Russ Huber said:

That makes it more difficult to find a 6 wing CCW rotation blade. Stamp Steel Westinghouse CCW rotation brass blades are more common but fit a 5/16" shaft. 

You could look into how involved it is to turn your stator around in the housing along with the stator wiring for CW rotation. 

Or, you could "carefully" re-pitch the wings on the blade you have. Using a channel lock pliers with the jaws wrapped with something soft and taped, you grab each wing one by one down by the hub spider finger and bend it opposite pitch. You would have to get a small 12" section of 3/8" shaft to put the blade on and clamp the 3/8" rod in a table vice to secure the hub to do the bending. You will then need a strobe to tweak all the blade wings into sync.

Or, you can live with what you have, or, maybe someone has a better idea?

You're correct. I have a Westinghouse stamp steel CCW rotation 6-wing brass blade, which I thought I could make use of, but found out it fits only 5/16" shafts. I think blades from Westinghouse tank fans may actually fit 3/8" shafts but finding a tank fan 6-wing blad is certainly not easy.

i am not currently that skillful to re-pitch the blade as you described. So I would probably just live with what I have or try to turn the stator around. This could probably be more doable for me I think. 

[Russ Huber]

37 minutes ago, Liem Nguyen said:

You're correct. I have a Westinghouse stamp steel CCW rotation 6-wing brass blade, which I thought I could make use of, but found out it fits only 5/16" shafts. I think blades from Westinghouse tank fans may actually fit 3/8" shafts but finding a tank fan 6-wing blad is certainly not easy.

i am not currently that skillful to re-pitch the blade as you described. So I would probably just live with what I have or try to turn the stator around. This could probably be more doable for me I think. 

Smart man! You might get a surprise on how easy it MAY be to turn your stator around. If you can re-channel your stator wires to the back after inserting the stator backwards, you done did it! If I am not mistaken, Roger mentioned he has one that turns clockwise? If so, there is a high probability somebody before him flipped his stator around. Those contraptions are designed to blow backwards.

[Roger Borg]

On 5/23/2023 at 1:21 PM, Roger Borg said:

Unsure, will put a magnet on it in the next day or so...

 

On 5/23/2023 at 10:40 AM, Liem Nguyen said:

With the reactor coil seen on the back of the motor, the separate speed regulator most unlikely helps to start the motor. Thank you for sharing the images of your fan. 

I'd also like to have and will search for a similar speed regulator for my fans. Btw, is the rear motor cover of your example brass or steel? 

Delayed reply, but wanted to let you know a magnet sticks to the rear bullet of the fan...

[Liem Nguyen]

On 6/2/2023 at 1:28 PM, Roger Borg said:

 

Delayed reply, but wanted to let you know a magnet sticks to the rear bullet of the fan...

Thanks Roger. Interesting there were variations of the same fan model. The other example (motor alone without tripod) that I bought from Russ also has a steel rear bullet.