Sewing machine motors

Check with a guy named Bill Harris at City Sewing Machines in Dallas Texas.

1-411 will get you his number I believe.

netmaker

a triac based AC motor controller. They work on AC only.

Dor DC you need a more complex pulse width controller.

many sewing machines are AC/DC. the modern ones use standard pulse modulation. (triacs etc) the old ones vary the field strength with some just varying the current throughput

Or if you really want to get down and dirty -- the early ones used a carbon pile where the amount of pressure put on a container of carbon granules regulated the the current flow - but since I'm an old fart, I'll bet none of you remember this one.

JR

... back in the old days, Aurora slot cars used a carbon pile controller to regulate speed... a stack of carbon discs inside a plastic tube that were pressed down with your thumb (man, my thumb would ache!)

of course, I had to take it apart (I think i was around 8 yrs. old)

I discovered that by stuffing some copper wire in place of some of the carbon, my cars ran a little bit faster - It took my brother a while to figure that one out!

not an old fart, just run a few more laps!

What a coincidence!, I bought an old Singer industrial sewing machine on ebay last week. It was sold as 240vac, but in this case with an induction motor - 1/4hp would you believe!

Interestingly, the speed control was by a mechanical clutch device - the motor runs at constant speed - and like a car, the clutch engages through the foot pedal.

I cannot use it yet because the belt is missing - but when fixed, I guess some smart footwork will be required.

In grandparent times, they were controlled with a series rheostat.

hi

sewing machine motors are series motor and hence you can control the speed with a small potentiometer,a resisrance which can be vriable so that the voltage supplied to the motor is varied

Hi electrical repairers,

I have a question. My mum's JUKI sewing machine DDL 5550-6 display shows the error code E7. What is it? And how can I fix it?

A technician checked it and says one of the serveral circuit boards that supplied the high voltage is faulty and is expensive to relplaced.

So, my questions to you experts is "is it possible to by-pass all or some circuit boards to just at least have some use of the paddle to work the sewing machine?"

And. What are the requirement for this to work?

Thanks,

Meddy

A machine like this, with built in boards and logic, will not be easy to operate with a bad board. One web site says that error code is from a seized motor, the logic detects the high current draw and stops and presents the error code. If you oil the motor end bearings, it might turn, but if the motor is wrecked??

Juke might help, they will send you a free manual and answer questions.

Juki website