Motor for electric leaf blower

[josephkk]

On Thu, 21 Mar 2013 23:30:58 -0400, "P E Schoen" <paul@peschoen.com>
wrote:

"Andy K" wrote in message
news:5cdac662-244d-401b-8eef-a1589674c1cd@googlegroups.com...

There are 2 pictures here.

http://s1127.photobucket.com/user/bicycle77017/media/Motor1_zps0b0fc792.jpg.html?sort=3&o=0

Try an ohmmeter on the brushes and rotate the shaft. It should alternate
between two values depending on the position if the brushes are aligned on
one pair of windings or two. Even better would be to apply a safe, low AC
voltage (6-12 VAC) and check the current draw. A shorted winding will draw a
lot more current. You may even be able to feel some torque on the shaft or
it may try to run slowly, and you may see where it hesitates.

Or you can grab an obstructionist Republican politician by the feet and he
will blow away the leaves with hot air

Paul

Republicans produce almost adequate amounts of hot air, but for really
serious wind you need a Democrat. The only problem is that generate so
much hot air that they are hard to control. All wild thrust and no wings
to control them.

?-)

 

On Sunday, March 24, 2013 12:51:19 PM UTC-7, Andy K wrote:

On Tuesday, March 19, 2013 5:51:11 PM UTC-5, Andy K wrote:

My leaf blower stopped working.







I tested the switch and it was fine.







Power is getting to the motor.







There was a black buildup on the armature, so I sanded it with a 1500 grit sandpaper.







Now the motor starts but it stumbles.







Is there anything else I can do or is the motor toast?







Thanks,



Andy



I fixed it.



Those ridges in the brushes weren't normal.



After sanding them smooth, the leaf blower is against producing 180 m.p.h. winds.



I think the brushes are made of graphite.



Andy

Impressive! I will have to keep this in mind.

By the way, these kinds of AC motors also function nicely with about 24V DC. (Yes, DC.)

Michael

 

[Jamie]

mrdarrett@gmail.com wrote:

On Sunday, March 24, 2013 12:51:19 PM UTC-7, Andy K wrote:

On Tuesday, March 19, 2013 5:51:11 PM UTC-5, Andy K wrote:


My leaf blower stopped working.

I tested the switch and it was fine.

Power is getting to the motor.

There was a black buildup on the armature, so I sanded it with a 1500 grit sandpaper.

Now the motor starts but it stumbles.

Is there anything else I can do or is the motor toast?

Thanks,

Andy



I fixed it.



Those ridges in the brushes weren't normal.



After sanding them smooth, the leaf blower is against producing 180 m.p.h. winds.



I think the brushes are made of graphite.



Andy



Impressive! I will have to keep this in mind.

By the way, these kinds of AC motors also function nicely with about 24V DC. (Yes, DC.)

Michael

Is it any wonder why they call them universal motors?


Jamie

 

[Robert Neill]

On Tuesday, March 19, 2013 10:51:11 PM UTC, Andy K wrote:

My leaf blower stopped working.



I tested the switch and it was fine.



Power is getting to the motor.



There was a black buildup on the armature, so I sanded it with a 1500 grit sandpaper.



Now the motor starts but it stumbles.



Is there anything else I can do or is the motor toast?



Thanks,

Andy

Hi there, looks like motor has commutator and brushes from your reply (assume universal series wound motor). Commutator segments may need undercutting as was common with automotive dynamo's. The Haynes Automotive Electrical systems service manual mentions an undercutting tool and in the starter motor chapter, a
growler tool is mentioned which checks the armature winding insulation by electromaganetic induction.