Lift max 5kg: pulleys vs actuator.

Projects General Guidance
1

My wife asked me for a solution regarding the fact that when we come back from shopping, we should have smth to take the bags upstairs.

Actually, I think that it is a bit too much assistance, but now, I have that idea in my mind. More by challenge.

So, i made my calculations, fixed the budget and I can't really choose between pulleys and actuator.
I would like a fast solution (60-80cm/s).

The height is 2,4m (we don't start from the ground and the roof is 2meters only in the garage).

My motor must have

P= (mg . h)/t
With m=5kg, g=9.81N/kg, h=2.4m and t=4s(say)

Pulleys can give me that speed. No issues. With the some tricks to assure stability (almost useless here, but.. I love to make things properly), that solution can still be low-cost (less than $300 not counting the work to create an opening for the lift $2000 gross).

But I fear actuators for that constraints would be way too expensive.

The other point is maintenance. I thought of a chain instead of a drive belt. But chains break. I think something else would be better. I saw a tv show in which they proved that a cable was more reliable.

What about actuators maintenance?

So, pulleys vs actuators? Chain vs cable vs driving belt? What is your opinion?

I don't want to fix it every two days.

Thanks

2

A pulley is not an alternative to an actuator.

Are you considering, as one option a winch that winds a cord over pulleys and, as the other option a linear actuator.

I think you need to make a drawing of the proposed mechanical arrangement and post a photo of your drawing.

...R
PS, I suspect your wife was being humourous.

3

How about a vertical linear motor.
It would probably be unique and quite a talking point for visitors.

4

treadmill motor. free if you can dumpster dive
low cost at thrift store.
maybe freecycle?
treadmill has variable speed drive module to make it easy.

chain is noisy, but easier.
cable requires a spool

you can buy a car winch for cheap and use that as the basis for the project.

the result, as far as maintenace goes, will be from your workanship. and things like using bearings and not just sleeves.

5

Is this inside or outside? How much room is available? How much weight will need to be supported. How wide/long does the lift platform need to be?

6

mikb55:
How about a vertical linear motor.
It would probably be unique and quite a talking point for visitors.
https://www.youtube.com/watch?v=vfwi8XLF2wQ
https://www.youtube.com/watch?v=2kO3dnEO0e0

mikb55,

This is absolutely what I need.

But There doesn't seem to be retailers for this tech.

Instead, and in the case i cannot buy a few of them, a linear motor would fit, don't you think?

7

JoeLinda:
But There doesn't seem to be retailers for this tech.

The commercial units are designed for precision which you don't need, so your budget should be more than enough to purchase some magnets, wood, copper wire (for coils), a power supply, cable harness, hall effect sensors and limit switches. Build a small prototype then upscale.

8

JoeLinda:
mikb55,

This is absolutely what I need.

But There doesn't seem to be retailers for this tech.

Instead, and in the case i cannot buy a few of them, a linear motor would fit, don't you think?

you will not find retailers, but sales reps.
for 2.5 meter lift, you should not be over $10,000 USD for one motor and the drive package.

9

one option you did not mention was a flat gear. put a motor with pulleys on a shaft and the drive would have a spur gear. the cost would be dependant on the weight/strength needed and the length of the gear.

my recommendation would be look at what the lift companies use. they have had decades of experience, have lots of engineers on staff, have to make a unit that is nearly infinitely reliable, has to past life-safety concerns.

IMHO, it is best to stay with main-stream technology to get a project working.

10

Various lift ideas.

11

I saw a lift made from garage door parts. Used the track as the guide and the motor/chain for the lift. Should be simple to find parts. Has limit switches build in and safety limits as far as load goes.

12

Waw lot of very good inputs.

I have to check your possibilities according to my budget. But I will make it happen.

Great community here :slight_smile: