Basic Motor Terminology and suggestions

[smcauley]

I have very little experiance with type of motors, sizes, styles and need some guidance.

I needed a 12v DC motor high tourque low rpm motor to spin a piece of threaded rod
I purchsed This unit off of amazon for under 10 dollars.
12V 6RPM High Torque DC Motor, Mini JGY 370 Motor Worm Gear Motor, Low RPM Reducer Motors Micro

I made up a couple pullys used a large O-ring for a belt and it does the job, I had to wire in a PWM to adjust the speed but it seems to work OK

I was hoping for somthing a bit less noisey, even with no load on it this loud. ( you get what you pay for)
I am hoping somone with more knowledge and experiance can suggest a better quality or more reliable manfacturer that has somthing similar that does not sound like its going to take off, or blow up?

 

[Nix Liou]

I have very little experiance with type of motors, sizes, styles and need some guidance.

I needed a 12v DC motor high tourque low rpm motor to spin a piece of threaded rod
I purchsed This unit off of amazon for under 10 dollars.
View attachment 38069512V 6RPM High Torque DC Motor, Mini JGY 370 Motor Worm Gear Motor, Low RPM Reducer Motors Micro

I made up a couple pullys used a large O-ring for a belt and it does the job, I had to wire in a PWM to adjust the speed but it seems to work OK

I was hoping for somthing a bit less noisey, even with no load on it th
I am hoping somone with more knowledge and experiance can suggest a better quality or more reliable manfacturer that has somthing similar that does not sound like its going

The pictured motor is a cheap brush worm gear to convert to low rpm. You might be able to make it quieter just by filling the gearbox with grease meant for plastic gears.

You could look at NEMA stepper motor options, with a stepper motor driver board. You may be able to get away with no gearing and just the stepper motor, depending on your needs.

What exactly is this being used for? What amount of torque, what torque range, etc?

Brushed DC motors are inefficient, low torque, and overall pretty mediocre- they're just cheap and simple.

 

[amberwolf]

Ditto to Nix Liou's comments above.

...except that a brushed DC motor can actually have some very high torque if it's designed for that, at the cost of efficiency, but with the plus of extreme simplicity of control.


If you are willing to tell us what you're trying to accomplish, in some detail, it will help us help you do that. Short of that, we can explain all the various ways you might do the job you've psoted about (spinning the threaded rod, with torque, rpm, degree of required control, control method, power supply, etc all unspecified, so a very general list of stuff that spins things ).

(plus we're always curious )

That said, some thoughts:

A gearbox of any kind is going to add noise. A tiny motor running a gearbox to get the same torque as a bigger motor is going to sound like a little box of bees, because of the speed it runs at.

A brushless version is significantly quieter, but the gearbox and the motor RPM is still going to make noise.

I have a number of kinds of really cheap RC Servos I am testing out for use in moving the Wolfybot around, and have finally gotten some brushless ones that are definitely quieter than the same servo with a brushed motor...but they still make the same gearbox noise.

A stepper motor is MUCH quieter, and can be used either to drive something like a regular motor, or to precisely move and hold something in place. they're still not silent, and they are much more complex to control than a simple brushed motor (or even an RC servo for a simple application where a servo tester can be used to do the manual controlling), but they're much better in general than the type of motor/gearbox you have already.

To control a stepper, you'll probably need to use an MCU (arduino, nano, esp32, raspberrypi, etc) but there are existing projects out there to run one from assorted types of user interfaces, and lots of control hardware and driver boards for mods to 3D printers, so it's all really really cheap to buy.

Depending on the threaded rod's mounting and usage, you may be able to mount a stepper directly to the end of it with a simple coupler. Here's an example of a "kit" on amazon with the coupllers and pillow block bearings for the shaft; was jsut the first hit in a google search

https://www.amazon.in/Threaded-Vertical-Horizontal-5x8x25mm-Coupling/dp/B0D7H6VVR7

You can probably use the same hardware to connect the rod to your existing motor's shaft instead of the pulleys, to make it more efficient, less complicated, and smaller.

 

[smcauley]

ok, you asked for it!
I have been working on building a " Weihnachtspyramide"
that is the german name for what is commenly called a Christmas Pyrimid
these go way back predating the christmas tree as holiday decorations
think of a multi level carousel with typically nativity scenes on each level
what i found interesting is the propulsion system.
typically there is a fan blade or propeller on the top that rotates the vertical shaft that spins the plaforms
candles attached to the structure create warm air that rises energising the fan
you can buy kits on line to build these from 18" to 48" , these come with steep price tags,

I have made one of these every christmas for the last few years
improving efficiancy and getting bigger each year

as they get bigger and heavier it requires more heat, I am using this inside the house where an adequate temperature differential becomes harder to maintain, the number of candles is a concern with children running around,

this years version is pushing 6 feet tall with 5 platforms
I chose to use an electric motor to drive it , more reliable, cleaner, and more economical than candels
I will be losing the "romance" of the candle powered machine, but gaining performance.
I like to think of it as replacing Therodynamics with Electrodynamics

so thats what I am building.
my driveshaft is a 5/16" threaded rod 6' long supported by bearings top middle and bottom
for drive pullys I am using Tinker Toys (perfect size), the platforms are 1/4 plywood ranging from 19" to 4" in diameter
there is very little friction, and its pretty well balanced,
I do not know how to calulate tourque, so I just say not too much (somwhere between 0 and million foot pounds)

this crappy little chinese motor seems to drive it just fine, it just sounds loud,

 

[Nix Liou]

ok, you asked for it!
I have been working on building a " Weihnachtspyramide"
that is the german name for what is commenly called a Christmas Pyrimid
these go way back predating the christmas tree as holiday decorations
think of a multi level carousel with typically nativity scenes on each level
what i found interesting is the propulsion system.
typically there is a fan blade or propeller on the top that rotates the vertical shaft that spins the plaforms
candles attached to the structure create warm air that rises energising the fan
you can buy kits on line to build these from 18" to 48" , these come with steep price tags,

I have made one of these every christmas for the last few years
improving efficiancy and getting bigger each year

as they get bigger and heavier it requires more heat, I am using this inside the house where an adequate temperature differential becomes harder to maintain, the number of candles is a concern with children running around,

this years version is pushing 6 feet tall with 5 platforms
I chose to use an electric motor to drive it , more reliable, cleaner, and more economical than candels
I will be losing the "romance" of the candle powered machine, but gaining performance.
I like to think of it as replacing Therodynamics with Electrodynamics

so thats what I am building.
my driveshaft is a 5/16" threaded rod 6' long supported by bearings top middle and bottom
for drive pullys I am using Tinker Toys (perfect size), the platforms are 1/4 plywood ranging from 19" to 4" in diameter
there is very little friction, and its pretty well balanced,
I do not know how to calulate tourque, so I just say not too much (somwhere between 0 and million foot pounds)

this crappy little chinese motor seems to drive it just fine, it just sounds loud,

Sounds like a medium sized NEMA stepper and driver, with a belt would do the trick. You can estimate required torque by feeling how much force it takes to start it rotating, say 1 foot out from the axle, and then press similarly hard against a kitchen scale (if measured in pounds, then ft lbs of torque)

 

[amberwolf]

Sounds like fun for the kids.

For this kind of thing I'd recommend a pretty simple system like the motor used in a microwave to spin the tray. Bigger version needed, but it would be pretty quiet. (not silent, but mostly just a hum). If you have an old microwave lying around unused, you could check to see if it's motor will push hard enough to do what you want.

Metal Gear Synchronous Motor AC 12V 5-6RPM 50-60Hz CCW CW 4W | eBay

DescriptionIt is mainly used for gluing machine,monitor, electrical curtain, stage lights, advertisement electrical movement, electrical and science and education instruments. Information About Synchronous MotorsA synchronous motor is one in which the rotor normally rotates at the same speed as...

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A quick guesstimate test is to push against the MW tray it until it stops or reverses direction, then push against your device's bottom deck the same way and see if it feels even remotely close to the same amount of push. If it doesn't (probably wont') then you can guesstimate how many times the force the MW motor makes that your device needs, and then lookup the force a typical MW motor makes, and then find a bigger synchronous motor with that much more force.

This is a slightly different version than used in MWs, but isn't really any bigger--just with an easier to use shaft.

AC 110V Synchronous Motor Plastic Gear CW/CCW 1RPM 7mm Eccentric Shaft w Hole | eBay

Description:It is mainly applied for electric fan , electric heaters, electrical curtain, gluing machine, monitor, stage lights, advertisement electrical movement and other kinds of electrical appliances. Feature: 1. Designed with 7mm eccentric shaft with hole.2. This product is made up of...

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Some bigger ones are still cheap; this one claims to be able to push 30kg (dunno how accurate that is)
US Stock Synchronous Motor 60KTYZ AC 110V 60Hz 2.5rpm CW/CCW 14W 30kg Gear Motor

US Stock Synchronous Motor 60KTYZ AC 110V 60Hz 2.5rpm CW/CCW 14W 30kg Gear Motor | eBay

Model: 60KTYZ. Synchronous Motor 60KTYZ AC 110V 50 /60 Hz 2.5 rmp/m CW/CCW 14W 30kg Gear Motor. Power: 14W. Rated Power:50 / 60HZ. Shaft Length:25mm. Speed: 2.5rpm. Hole Center Distance:50mm.

www.ebay.com