Reduction gear 1000:1, is it possible 2

[haleemeng]

Hey all, I have this problem that I need to reduce the speed of a motor from 1000 rpm to only 1 rpm. Is this possible in reality? And if there is a gearbox that does this, I want to knnow where to find it.

 

[ivymike]

http://www.honeybeerobotics.com/transmissions.html

 

[tbuelna]

hallemeng:

Take a look at harmonic drives:

http://www.harmonic-drive.com

http://www.harmonicdrive.de/en/2_2_3.htm

 

[israelkk]

Yes, it is possible but at cost of low efficiency.

 

[paulliu]

haleemeng:

The existing rotary vector drive can have
a reduction ratio of 1000, by using the
involute gears for its 1st planetary drive,
and cycloid, harmonic or Ikona gears for
its 2nd planetary drive.

But I also have several questions for you:

(1) Does it require to be back-driveable?

(2) Is this a plastic gearbox or metal gearbox?

(3) What's the approximate dimension?

If it's a plastic box, I don't know at the moment
whether harmonic drive can be used.

Good luck!

 

[haleemeng]

Many thanks to you all: ivymike, tbuelna, israelkk and paulliu. About this gearbox, now I think that I will need even a bigger reduction ratio, because the motor offered to me at the moment is 500 rpm, and I need to reduce it to 0.05 rpm.

The answers to paulliu's questions is as follows:
1- No, it does not require to be back-driveable.
2- It is a metal gearbox, not a plastic one.
3- I do not have any restriction on the dimension side.

 

[paulliu]

haleemeng:

Now for a speed reduction ratio of 10,000, a recent
example I saw, employed two gearboxes with a speed
reduction ratio of 100 for each of them, and each
of which may use the harmonic gear drive, or worm-gear
drive, or involute planetary gear-drive et. al.

 

[monkeydog]

Check out

http://www.globe-motors.com/home.html

 

[haleemeng]

Thanks paulliu and monkeydog.

About using 2 gearboxes, it seems like a good idea. Any advise about where to get them, baring in mind that I will need a max output torque of 60 Nm

 

[sacem1]

Two worm gear reducers one attached to the other with 100:1 ratios (usually the highest you get in commercial units) will render the 10,000:1 ratio you need your efficiency should be down to around 0.6 so if you need 60 Nm you should aim at an input of:
100Nm/10,000 = 0.01 Nm = 0.074 ft-lb input < 1 inch-lb

Which puts you at the really smallest section of speed reducers for the input side and even the secondary one can be a less than an inch in sizing. (worms speed reducers are determined by the distance between axis of the worm and wheel)

Youll find those in the Grainger catalog as sub-fractional speed reducers

SACEM1

 

[plasgears]

There are some sub-fractionals, both AC and DC, in the Grainger catalog that will do the job at low cost, one gearbox. I designed some of them.