Crazy project time… Toby you know what these are like…
I need to move 60 things in and out on a linear actuator of some kind 2 meters in a relatively controlled way, i.e. I can set a depth. With reasonable speed.
I’ve been looking at linear telescopic actuators but they are used for lifts normally and they have way for force than I need, and don’t like being wall mounted… I need to move up to 2 meters in and out of a wall.
Weight on the end is > 5KG with cabling coming back from there.
Rack and pinion, I’d have thought. You could have separate load-bearing and drive wheels so you don’t put excess load on the motor. But you’d need space behind the machine for them to retract into.
60 things? One at a time? All in the same plane? In different order, or can they be on a rail? Each has it’s own cables and weighs 5kg+?
And how accurate/fast?
Telescopic car arial method?
Existing telescopic arials may not be long enough or strong enough but you could copy the method
Telescopic tube pushed/pulled by a spring wound on a drum by a motor.
The spring could be sprung steel or the coiled metal flexible drain clearing stuff.
When you push it down a tube its fairly rigid but you can coil it up.
Wound on a drum driven by geared motor/stepper motor.
Telescopic rod could be thin steel or even plastic piping.
Would be fairly compact as the actuator is wound on a drum.
@tomnewsom nah, such things already exist but they require the same length as they protrude behind, i.e. they double their length, I want to do something maybe 30 cm long that can become 2m 30cm long. or there abouts.
@Dermot yeah I need a device I can hang 5KG off the end and move back and forth quickly and smoothly, to various different positions. Each of the units needs to be independently able to move in and out.
@gordonendersby Yes, but they won’t be 2 meters long, or able to hold 5KG of weight 2 meters from the base.
Thats just the compact drive to push something out and pull it in.
A nested cantilevered drawer slide type structure could give you the 2meter reach and support the weight.
Yeah, I was thinking about that, but most draws don’t extend 2 meters, however more importantly this needs to be an off the shelf unit that is safety rated etc… I have looked but not found a single actuator capable of moving that far, and the telescopic ones only go up down, they can’t be mounted sideways.
Also most actuators pose a serious hazard because they are very strong.
5kg at the end of a 2m cantilever will require real mechanical strenth.
2m extension using only 30mm lengths is a lot of joints.
I don’t think the spec is possible.
I think you either need to dramatically reduce the weight to hold, or accept you need 2.5-3m behind. If the former, you have a range of mechanical options. If the latter, it’s within spec of a lot of tried and tested industrial kit.
The best place to source this kind of kit I found was http://zappautomation.co.uk. They a) have prices on their website (surprisingly rare) and b) have decent cheap options. They could probably customise a LEZ 1 linear actuator for you.
“Off the shelf unit safety rated”.
Aah, I was thinking you could make it yourself from aluminium extrusion with a compund cantilever type action so while one could extend 1 meter another one mounted on that could extend a further meter. Or split it down into more sections.
It’s not for a wall, but to come out of a surface basically, and the depth of that needs to be less than the extension… Was thinking of a scissor type mechanism.
Yes, scissor on a lead screw is the obvious answer to get your 7x extension. To get the mechanical strength with minimum droop will require it to be quite tall I’d have thought, like 0.5m ?
If there’s a budget and safety is an issue, I’d give Zapp a call and see what they can come up with.