Newbie and looking for a certain motor

Hi guys!

I do not have much knowledge about motors so I thought about asking here.

I am looking for a motor that is kinda small-medium size.
It should handle 1-2kg force/weight.
It should have the option to adjust speed depending on the voltage input.

I do have a 12v adapter here at home, just plug it in and woila but the adapter output only 600mA, isn’t that a bit low?
I also draw a fast picture showing what I am going to use it for.

Edit: I am also looking for tips on how to attach the wooden wheel/circle on the motor. If I glue it, it will probably loosen up after using it a long time.
Edit2: I am sorry, I saw that I had written three when I mean, of course, tree :slight_smile:

12V x 600mA = 7.2W output.
What if you mount the motor on arm and let its shaft drive the outer rim of the larger wheel? Than you get by with a small, lower power motor.

Look at sites like this also, lots of 12V motor options.
http://www.mpja.com/DC-Motors/products/100/

I am sorry, I saw that I had written three when I mean, of course, tree

Ok, I give up. What is a "tree weel" ?

CrossRoads:
Look at sites like this also, lots of 12V motor options.
http://www.mpja.com/DC-Motors/products/100/

Hi and thank you for the help! I am browsing that site now that you recommended but I think it is so hard to know which one works like the way I want it to…

This is how I was thinking about the setup. Motor attached to arm, wooden wheel attached to motor.

raschemmel:

I am sorry, I saw that I had written three when I mean, of course, tree

Ok, I give up. What is a “tree weel” ?

What I mean is a wheel, a circle, that is made out of wood material. But I misspell stuff all the time and English isn’t my first language. Sorry.

Maybe look here instead

Lots of motors, lots of ways to attach a gear or pulley or something to the motor that your wood wheel could attach to.

CrossRoads:
Maybe look here instead
http://www.servocity.com/
Lots of motors, lots of ways to attach a gear or pulley or something to the motor that your wood wheel could attach to.

Thank you so much! This site was really great!

I found this one
http://www.servocity.com/html/45_rpm_hd_precision_planetary_.html#.U-FC6GNeIzg

Operating Voltage Range: 6~12VDC
Rated Load: 21 kgf-cm (291.6 oz-in)

Min. Stall Torque: 153 kgf-cm (2124.8 oz-in)
Max. Stall Current: 20A @ 12VDC
Output Power at Max. Efficieny: 9W

Now I know my adapter outputs 600mA which is 7.2w but that is okey. I will probably not use the motors max efficiency.
Does it have the capacity to lift/force 1-2kg?

Sorry for all the questions and all the misspelling.
Thank you for the help,
regards!

Edit: Maybe this one is better. It does not require as much watt as the other one
http://www.servocity.com/html/52_rpm_precision_planetary_gea.html#.U-FFcWNeIzg

What I mean is a wheel, a circle, that is made out of wood material.

I think the term you are looking for is "wooden wheel".

knegare:
Hi guys!

I do not have much knowledge about motors so I thought about asking here.

I am looking for a motor that is kinda small-medium size.
It should handle 1-2kg force/weight.
It should have the option to adjust speed depending on the voltage input.

I do have a 12v adapter here at home, just plug it in and woila but the adapter output only 600mA, isn't that a bit low?
I also draw a fast picture showing what I am going to use it for.

From what I can see you don't understand torque. Torque is twisting force and its
units are force x distance (or energy / angle).

Your diagram doesn't show how far the 2kg weight is from the axis - that's going to
determine the torque.

If I guess its going to be 0.1m from the axis, a 2kg weight has about 20N of force
due to gravity, so the torque needed to just rotate the wheel will be 20 x 0.1 = 2Nm
(newton-metres). Power = torque x angular velocity, so a 10W motor driving
a constant 2Nm load would be limited to 5 radians/second (50 rpm or so) at best.

In practice reduction gearing would be used for high-torque loads.

However you really really don't want to spin an eccentric weight like that unless you
want to deliberately shake the structure to which the motor is attached. You may
overload the motor bearings too.

Normally anything you spin with a motor would be balanced...

What exactly do you want to achieve?

[
Torque = tangential force (in newtons - N) x radial distance (in metres -m)

Power = torque (in newton-metres - N-m) x angular velocity (in radians/second - rad/s)

1 rad/s is approximately 10 rpm
1 kg has force on it due to gravity of approximately 10 N
]

MarkT:
From what I can see you don’t understand torque. Torque is twisting force and its
units are force x distance (or energy / angle).

Your diagram doesn’t show how far the 2kg weight is from the axis - that’s going to
determine the torque.

If I guess its going to be 0.1m from the axis, a 2kg weight has about 20N of force
due to gravity, so the torque needed to just rotate the wheel will be 20 x 0.1 = 2Nm
(newton-metres). Power = torque x angular velocity, so a 10W motor driving
a constant 2Nm load would be limited to 5 radians/second (50 rpm or so) at best.

In practice reduction gearing would be used for high-torque loads.

However you really really don’t want to spin an eccentric weight like that unless you
want to deliberately shake the structure to which the motor is attached. You may
overload the motor bearings too.

Normally anything you spin with a motor would be balanced…

What exactly do you want to achieve?

![
Torque = tangential force (in newtons - N) x radial distance (in metres -m)

Power = torque (in newton-metres - N-m) x angular velocity (in radians/second - rad/s)

1 rad/s is approximately 10 rpm
1 kg has force on it due to gravity of approximately 10 N

Hi and thank you for the explanation! I do realize now that I have almost no knowledge what so ever when it comes to motors and I will study it because I want to learn while building, not just build and have all my answers given to me.

I even realised now that I don’t know how big my wooden wheel will be so I can not determine what motor I shall use. Could only guess.

Anyway, what I am trying to do is a (sorry if I am breaking the rules now) sex toy. You attach a fleshlight to the wooden-wheel-arm and this will make the fleshlight go up and down automatically. Then you could e.g. lay down in the bad, put the machine/product above you hip and then use a control to adjust the speed of the “elevator” fleshlight.

Edit: Now lets see if I got this right.
See the attached picture.

Torque = tangential force (in newtons - N) x radial distance (in metres -m)
Torque = 20N x 0.05 (20x0.05 = 1Nm)
Torque = 1Nm

Power = torque (in newton-metres - N-m) x angular velocity (in radians/second - rad/s)
Power = torque (1Nm) x 5 (50 rpm)
Power = 5 watt?

Unusual but not unprecedented... I guess you'll have to devise a way of
measuring or estimating the forces involved, er, in private?

MarkT:
Unusual but not unprecedented... I guess you'll have to devise a way of
measuring or estimating the forces involved, er, in private?

Haha of course, just don't want a motor that is too weak.
Anyway, I contacted servocity.com (great guys!) and he advised me to purchase a motor with the double amount of torque so that the motor doesn’t have to work too hard.

So I am looking for a motor with a torque of at least 4Nm (or ~700oz-in), running on 12v and runs at >=50rpm.
Do you guys have any motors in mind?

Thank you all for the help. I have learnt a lot about motor!

Edit: This is the one I am going for.
http://www.servocity.com/html/60_rpm_hd_precision_planetary_.html#.U-KSkWNeIzg