REPULSION START.....INDUCTION RUN MOTOR
Intro: REPULSION START.....INDUCTION RUN MOTOR
A large cast iron ( 12" jaw ) wood planer powered by a Repulsion-Start Induction-Run motor.
This is a class of motor that overcomes the induction motor's low starting torque
and incorporates the large starting torque,
while loosing the noise and brush wear of a repulsion motor.
For those who are not interested in the speed torque can skip the next step.
Curious about IRON PENNIES well you are in luck.
This is a class of motor that overcomes the induction motor's low starting torque
and incorporates the large starting torque,
while loosing the noise and brush wear of a repulsion motor.
For those who are not interested in the speed torque can skip the next step.
Curious about IRON PENNIES well you are in luck.
STEP 1: THE NEED... THE NEED............. FOR TORQUE and Speed
The starting of a large Planer takes more toque then an induction machine can provide
in accelerating the mass of the single edge blade in a massive flywheel.
The first graph ( Third Pic ) plots the speed torque of a repulsion motor
which has a strong starting torque at low speed.
See the ( First Pic ) a simplified repulsion motor wiring diagram.
.
After 40 seconds the repulsion motor reaches speed and the brushes lift off the
commutator turning the motor into an induction machine for planing.
Here is a pointer to an actual repulsion motor starting a planer wind-up
that you can see and hear.
See the ( Fourth Pic ) a simplified Induction motor wiring diagram.
The second graph ( Sixth Pic ) plots the speed torque of a Induction motor
which has almost no starting torque at all ( used for fans )..
in accelerating the mass of the single edge blade in a massive flywheel.
The first graph ( Third Pic ) plots the speed torque of a repulsion motor
which has a strong starting torque at low speed.
See the ( First Pic ) a simplified repulsion motor wiring diagram.
.
After 40 seconds the repulsion motor reaches speed and the brushes lift off the
commutator turning the motor into an induction machine for planing.
Here is a pointer to an actual repulsion motor starting a planer wind-up
that you can see and hear.
See the ( Fourth Pic ) a simplified Induction motor wiring diagram.
The second graph ( Sixth Pic ) plots the speed torque of a Induction motor
which has almost no starting torque at all ( used for fans )..
STEP 2: BIG CAST IRON PLANER
IF you skipped here from the Introduction you may want to use this pointer to see and hear
an actual repulsion motor wind-up sound starting this planer.
A safety cover blocks access to the very dangerous spinning steel cutting flywheel blade.
an actual repulsion motor wind-up sound starting this planer.
A safety cover blocks access to the very dangerous spinning steel cutting flywheel blade.
STEP 3: WHATS a REPULSION MOTOR
As you can see the repulsion motor uses stationary brushes on the rotor
with attached commutator to achieve the starting torque.
This configuration is much like a shunt motor.
with attached commutator to achieve the starting torque.
This configuration is much like a shunt motor.
STEP 4: USING THE PLANER
Here are some pictures of the plane taking a cut on a solid 4×4 segment.
This is a pointer to a planning operation you can watch and hear.
Note how the safety guard keeps the errant fingers away from the blade.
I have trimmed a solid core door in three passes to fit an older door jamb
on this machine.
This is a pointer to a planning operation you can watch and hear.
Note how the safety guard keeps the errant fingers away from the blade.
I have trimmed a solid core door in three passes to fit an older door jamb
on this machine.
12 Comments
pfred2 12 years ago
iceng 12 years ago
In term of motors the older ones were more efficient and built to last.
A
pfred2 12 years ago
That old motor I have is just too big. It is huge and is only a half a horsepower. I got a great deal on a 5 HP Weg motor, and have that on it now. All the induction motors I have today will last me the rest of my life. But I might use that repulsion one when I modify my homemade lathe some more. Right now I'm using a little half horsepower squirrel cage motor on it.
I'd have to totally redo how my motor is mounted to use that big beast.
iceng 12 years ago
is the motor weight the belt way tension ?
Isee a heavy solder iron hanging from a tray.
What is most curios is the armature rotor in
your lathe could it be for mass to smooth your work,
or a shaft extension ?
pfred2 12 years ago
What looks like a motor armature is actually a Jacobs No. 36B 3/4" chuck. Mounting it was by far the single most difficult task of making the entire machine. In the first image you can see my previous two failed attempts at getting the threads axial to the spindle shaft. I know now it isn't one of those things that just happens.
If a picture is worth a 1,000 words it'd still take a lot of pictures to tell part of my lathe's story. So here is another. In it you can see a wooden column that partially supports the motor's weight. The column is movable so I can adjust it for the right amount of weight to maintain belt tension.
Works pretty good, though I must admit it wasn't in my original design. The lathe was sort of grown organically from my junk collection.
iceng 12 years ago
"organically grown" is just prolonged fun.
I never expected a Jacobs No. 36B 3/4" chuck makes sense though.
Big irons are safer to cool hanging then flimsy tip over supports,
one has got to use a wide half pulley arrangement to keep the old cord
from sharp edge short cracking.
pfred2 12 years ago
iceng 12 years ago
As Robin would say "Holly Stepper" pfred :-D
You may note on national News tomorrow, we had a raging wind
blown blaze the "Washoe Road Fire" in the valley between Reno
and Carson City (4500') while it is snowing ten miles west at
Lake Tahoe (above 6500') ASL...
A
pfred2 12 years ago
It is a star in a video I made:
http://www.youtube.com/watch?v=GU2GaSMPxNI
More about that whole deal here:
https://www.instructables.com/id/TB6560-Microstepping-Bipolar-Chopper-Stepper-Motor/
I live in the woods and worry about forest fires. So far so good though.
iceng 12 years ago
russ_hensel 12 years ago
I love this motor and its lathe, even use it on occasion.
iceng 12 years ago
As opposed to today's motors designed to run HOT and wasteful
because that saves on copper and iron in lowering the price.
A