# Telescoping sliding mechanism

Hi

Im curious about how this mechanism work as shown on the video at time 1:00

The machine has mechanical arms that extends 3-4 times its length (telescoping?), and it works 2 ways (to the left and to the right of the machine).

Any hint?

Thx

Any hint?

Lots of money and teams of highly qualified, experienced mechanical engineers backed up by talented machine builders.

You can buy drawer slides that work on the same principles, at your local home improvement shops.

I agree. Drawer slides.

...R

Well... Yes i kinda guessed that drawer slider would help experimenting..

Ok let me try again.. I tried drawing a few models on how the telescoping arms might work, but couldnt get the concept of moving the two stages of the telescoping arms to move together in each direction (and returning to the original position). I'm thinking there might be a way to move them using belts / chains, and a single motor? And it is allowed to move to the left and to the right of the machine?

Any idea on how the belts / chains might be connected to the stages of the telescoping arms?

I would connect the belt or chain to a platform mounted on the drawer slides.

gearwheel, the gears engage in top and bottom and the wheel has its bearings
on the middle slider. The middle slider is driven from below on rack and pinion.

Well that’s my best guess. The gear guarantees the middle slider moves at
half the speed of the top runner keeping the strongest configuration at maximum
extension.

BTW its a nice machine, but I would have added multiple fork-lifts to it so it could
more loads more efficiently. Perhaps its the bottom of the range!

Mark, actually, the second and third stages of the telescoping arms moves at equal speed. The second stage move at speed=x with relative to the platform, and the third stage moves at speed=x also, with relative to the second stage.

The part im curious about is that this thing moves in both directions, and it extends 3-4 stages.

I attached a simple drawing of how i thought a single slider would work, it works on two directions, and a single motor to drive it.

If you look in the slots in the platform you can see there's a gear-sprocket-gear (left to right) combination. For each row the leftmost gears are idlers, the sprockets are fixed in position, and the right side gear is driven (motorized). Those driven gears connect with a rack on the bottom, moving stage to extend it.

Wrapped around the bottom moving stage there's a loop of roller chain. There's an idler sprocket on each end of that stage so the chain can rotate around it freely. When the platform's gears are driving the rack on that bottom stage the chain engages on the fixed sprockets in the platform and rotates around that bottom stage. Fixed teeth on the next, second stage engage into that roller chain and that's what drives that second stage. You'd have to stare at a forklift to understand how that roller chain design works -- except forklifts don't use a loop of chain (just a "U") since they have gravity to retract their height.

As to what is driving the top/third stage, since there's no roller chain to be seen, it must be a rack in the first stage, an idler pinion in the second stage, and then a rack in that top stage. Look at dining room table "equalizer slides" to understand how that works. I'm assuming they're using racks and pinions to keep the overall height of the slides as low as possible (roller chain would increase the height or width too much).

Ah. I actually found this on youtube Telescopic sliding gate - YouTube

sutejo:
Ah. I actually found this on youtube https://youtu.be/ASAxH51ify8

Yep that looks about right for the first stage. The video certainly explains it better with pictures than I did with words

This video is an example of the rack/pinion extension mechanism for that top platform (same video guy on Youtube): Gear rack drive for increasing stroke 2 - YouTube

Yeah this is like super popular these days. A lot of machines are using this as a main mechanism. I also know that a lot of people are trying to incorporate this type of mechanism into their everyday life. For example a lot of designers are using the main principals of this thing and add it into drawers. A friend of mine lives in Germany and we have been visiting him not so long ago. He was right in the middle of buying new furniture and we went shopping together. They have a whole isle with telescopic drawers (It’s called schubladenschiene over there). And there are actually some really nice options that are not that expensive. So I am glad that people are implementing these types of things in their everyday lives. It’s nice to live in the middle of a technical revolution.

If you want people to view the video, DON'T make it a PRIVATE video.

Paul

Paul_KD7HB:
If you want people to view the video, DON'T make it a PRIVATE video.

That was a 3+ year old Thread

...R

Robin2:
That was a 3+ year old Thread

...R

Caught me again!!!

Paul