Lego GBC Scissor Lift Module

[sawyer klegr]

This Lego GBC Module uses a Scissor Lift mechanism to lift the balls up. The mechanism is quite reliable and sturdy, I never had problems with the balls falling out. The gear train is long but it does not have much friction because the stepper does not use much power. I would like to make one with more lift mechanisms similar to Akiyuki's six heads module but I don't enough of the cup pieces. The LDD file is here.

More photos here.

[Bartybum]

Very cool, great work. I love that you can regularly come up with fairly compact yet complex mechanisms like this one

[iLego]

This is so cool !

It looks simple enough at first glance, but when I look carefully, I can see so many small details which add up to make the whole thing work.

I really admire the skills needed to make these working Technic contraptions.

[Ankoku]

I really like the motion in that one!

Great work!

[Captainowie]

It's neat, but poorly named - a scissor lift is one of these

and that's not what your mechanism does - the pivot point of the arms is behind the point of application of force. Your machine is more like tongs than scissors!

The gears on the back stabilisers of the arms; are they just for decoration? I couldn't fathom their function.

Owen.

(NB I pulled the URL for this image as a result of an image search. I make no promises that the image will be available at any time into the future. I didn't even look at what website it was from.)

Edited November 20, 2018 by Captainowie
Add image disclaimer

[sawyer klegr]

14 hours ago, Captainowie said:

It's neat, but poorly named - a scissor lift is one of these

and that's not what your mechanism does - the pivot point of the arms is behind the point of application of force. Your machine is more like tongs than scissors!

The gears on the back stabilisers of the arms; are they just for decoration? I couldn't fathom their function.

Owen.

(NB I pulled the URL for this image as a result of an image search. I make no promises that the image will be available at any time into the future. I didn't even look at what website it was from.)

Hahahaha, thanks ;) I could not think of anything better to call it. The top arms are there to keep the balls in the cup, if they were not there the balls would fall out before they reach the top.

18 hours ago, Ankoku said:

I really like the motion in that one!

Great work!

Thank you! I am glad you like it.

[Ankoku]

The name will stick.

Are you planning on any instructions?

Thanks for all the photos!

[Bartybum]

Just now, Ankoku said:

The name will stick.

Are you planning on any instructions?

Thanks for all the photos!

There’s an LDD file :)

[Ankoku]

I fail quite hard at times :P

[Lakop]

very nice.

H

[sawyer klegr]

On 11/21/2018 at 10:17 AM, Ankoku said:

I fail quite hard at times :P

Hahaha, I know exactly how you feel ;)

[Frequenzberater]

On 11/20/2018 at 7:10 AM, Captainowie said:

The gears on the back stabilisers of the arms; are they just for decoration? I couldn't fathom their function.

They are attached with a blue friction pin. Therefore, I expect it to be necessary that the scissor remains in open position when moving back to pick up the next ball. 

 

@sawyer klegr Again a great module! 

[Captainowie]

1 hour ago, Frequenzberater said:

They are attached with a blue friction pin. Therefore, I expect it to be necessary that the scissor remains in open position when moving back to pick up the next ball.

Ah yep, that'd do it. Thanks.

[sawyer klegr]

On 11/22/2018 at 5:42 PM, Frequenzberater said:

They are attached with a blue friction pin. Therefore, I expect it to be necessary that the scissor remains in open position when moving back to pick up the next ball. 

 

@sawyer klegr Again a great module! 

Yes, that is what they are for.

[Ankoku]

@sawyer klegr Spotted out in the wild!

 

 

[Berthil]

On 11/20/2018 at 9:44 PM, sawyer klegr said:

It's neat, but poorly named - a scissor lift is one of these

Correct on the fact it's neat but poorly named, I've build one which can carry the correct name :)

 

[doug72]

On 12/13/2018 at 11:35 AM, Berthil said:

 I've build one which can carry the correct name :)

There appears to be two small shock absorbers on the moving legs at bottom of the module, are these two assist with the lift or retard it when descending  or are they just acting as sliding guides ?
Might have ago at replicating this module but using a linear actuator instead & a reversing unit.

Edited December 15, 2018 by Doug72

[Berthil]

6 hours ago, Doug72 said:

There appears to be two small shock absorbers on the moving legs at bottom of the module, are these two assist with the lift or retard it when descending  or are they just acting as sliding guides ?

Both :)  they are in fact 6 soft springs, 3 on each side. 6 to get enough travel distance and damping and while compressed they aid in getting the lift back up. They also tilt the bottom of the inbox so 3-way function for this mechanism.

[sawyer klegr]

On 11/29/2018 at 3:36 PM, Ankoku said:

@sawyer klegr Spotted out in the wild!

 

 

Cool! I hope it is working well :)

[RohanBeckett]

I took mine to Brickvention, but unfortunately, it was dropping balls too often...  Not sure why, and haven't had time to go back.. the balls would just bounce out of the cup/hub 50% of the time

Maybe I need to tweak the timing of the stepper blocks a small amount?

[sawyer klegr]

On 2/5/2019 at 3:52 PM, RohanBeckett said:

I took mine to Brickvention, but unfortunately, it was dropping balls too often...  Not sure why, and haven't had time to go back.. the balls would just bounce out of the cup/hub 50% of the time

Maybe I need to tweak the timing of the stepper blocks a small amount?

That could be it, have you made sure that there is not to much friction on the drive train to the stepper? That could also help.

[RohanBeckett]

had another play with it last night, as I have a small GBC show on tomorrow... have adjusted the timing a bit, and it seems a bit better.. but we all know how well behaved GBC's can be on the workbench, compared to when a crowd is watching!!!

 

Balls still seem to want to bounce a little bit, when they hit the cup/hub.. so I'm thinking one day I might really try to redesign that section a bit, so the balls fall in a bit more gentle somehow?

 

[doug72]

I had problems on a GBC module I built with balls bouncing out of cups, I used a short swinging arm to slow the balls down a bit.
Made using a  no. 1 connector with a 3L axle hanging on a friction free pin.

[RohanBeckett]

I took it to a show last weekend, and it worked better.. but it's very sensitive to the angle of the table.. I was on plastic blow-mold trestle tables, that are never perfectly level... when I jacked up one side, it behaved better

But in the end, after 5 hours running, it broke down.. snapping the end of the 3L thin liftarm, forming the crankshaft - I suspect due to being jammed against dropped balls - the infamous akiyuki-style-frame-ball catcher :(

But I have a few ideas to improve it!