Calculating Torque and RPM for Moving a Drawer with a Tiny Motor

[BeautifulInsanity]

Hey I'm trying to work out a physics calculation,

if I have a drawer (any type of drawer regardless of size), that sits on wheels so friction = negligible, and it is as an example 14 inch deep, 6 inches high, and 20 inches wide, it has an empty weight of 4 pounds, and a loaded weight of 10lbs, how much torgue and / rpm do I need to move that drawer 12 inches from starting point, allowing for 2 inches to remain in the original travel path. Also with consideration the drawer would need a reverse function following its travel back to start. am I looking at 100rpms a/c tiny motor should do it ?

Ideas ...thoughts ... questions...considerations...

Thanks a bunch.

 

[Bystander]

friction = negligible

How much torque? Anything greater than zero; now would you like to rephrase the question?

 

[berkeman]

Welcome to the PF.

sits on wheels so friction = negligible

Not really. You can minimize the friction with good quality bearings, but the minimum torque will be determined by the linear force required to overcome the bearing friction. Add more torque to be able to accelerate the drawer quicker.

What kind of drive are you thinking of using? It will need to be tolerant of people pulling and pushing on the drawer, most likely...?

Have you looked at the drive mechanisms that are used for PC DVD drawer opening/closing? That might give you a starting point...

 

[BeautifulInsanity]

the drawers are specifically for a my bedroom dresser (i'm going to build from scratch) ...anyway...drawers always have rails to slide on. They also have a maximum travel (unless you pull the drawer completely out)... so this is a youtube video of sort of what i want to try... the only difference instead of going up and down it would travel front to back. I suppose it could be a servo, or a linear actuator, but i was thinking just a simple little motor that pushed when you pushed a button, then would stop, then push the button for retraction.

 

[Bystander]

https://www.google.com/search?rlz=1...67k1j0i131k1j0i7i10i30k1j0i13k1.0.hoOxwiRWba0 ?

 

[Dr.D]

i was thinking just a simple little motor that pushed when you pushed a button, then would stop, then push the button for retraction.

As a general rule, motors don't push or pull; they go round and round. If you want push or pull, you have to put something between the motor and the object to be pushed or pulled.

 

[BeautifulInsanity]

yeah I was thinking of a winding rod with a gear ...(like a worm screw - i think they call it), but it could also be done with a convey belt system (miniature version), where 2 gears are housed on the drawer and move internally to a belt in a linear motion with a 5th wheels receiving power from a motor via gears. You'd have to do 2 sides, unless it all can fit underneath the bottom, keeping in mind the actually weight of the drawer & contents would be transferred to rail guides (metal) with a weight capcity of up to 50 lbs, so there's no load bearing on the motor or components, basically it just has to slide it front & back.