Is it possible to connect 2 LA's

[legolijntje]

I was thinking; is it possible to conect 2 LA's like this:

They must work.

The picture is from HAN.

[Zerobricks]

I managed to use 2 LA's as a single one like this:

Edited October 4, 2010 by Zblj

[legolijntje]

I think u got a wrong pic :D

I managed to use 2 LA's as a single one like this:

No, it's not the wrong pic; it's an example whit pneumatic. Your idea is good , but can it be used on a truck or smothing else?

[freakwave]

I was thinking; is it possible to conect 2 LA's like this:

They must work.

The picture is from HAN.

Easily: NO

With Efforts: YES

The crux is that you have to make something that can rotate with an axle, but has to move along the axle as well when the LAs extend. The solution coming to my mind would be a construction with a worm-gear that can slide over a distance of 5L.

Now as the LA move they will also pivot somewhere. At this pivot the axle driving the worm-gear needs to have a Universla Joint respectively a gear rotating on this pivot point.

See the 8043 for U-joints going through pivot-points as a reference!

freakWave

I think u got a wrong pic :D

I managed to use 2 LA's as a single one like this:

Isn't the whole thing the rotating? I mean the bodies of the two LAs including the bottom rod? How is this thing doing in real life? extending both at the same time or extending the upper one first, little puzzled...

so I need to try this at home...

[Milan]

Zblj, that is very nice idea.

Do they spin when they are being operated? I guess they do.

[Zerobricks]

Yeah, they spin too, but thats the only way for it to work. Internally they are connected via a 2L axle. They are great fio supporting weight, like crane booms and such. On thing when extending this LA combo OVERRIDERS internal clutch, so dont put too much torque on them.

[backbone]

Check this:

http://technicbricks.blogspot.com/2008/08/tbs-techreview-05-technic-pf-linear.html

[roamingstop]

Actually for low torques you could use the rotating head (of the first LA) to drive the axle thread (of the second LA), with the frame for the second held rigid using a supporting beam (as per the pneumatic cranes). However it might not work for higher torques / load.

[legolijntje]

Check this:

http://technicbricks.blogspot.com/2008/08/tbs-techreview-05-technic-pf-linear.html

Can you post the picture? For some reason I can't see technicbricks the last time, it doesn't work.

[efferman]

maybe this is a solution for you.

Edited October 4, 2010 by efferman

[Milan]

Can you post the picture? For some reason I can't see technicbricks the last time, it doesn't work.

There are 30+ pictures, here are few most important:

And a video:

[Blakbird]

Barman has designed a whole series of parts to do just this, and has presented them on his Brickshelf page. The image I've linked below shows and animation of his concept. Very well thought out!

[Burf2000]

Barman has designed a whole series of parts to do just this, and has presented them on his Brickshelf page. The image I've linked below shows and animation of his concept. Very well thought out!

Very cool

[freakwave]

So I tried my sliding worm-gear suggestion and it works. I did not try it with a lot of load but the principle is ok. Was too late to take pics, sorry. I will do so may be tomorrow.

A little disadvantage of replacing such a "quattro" cylinder construciton with LAs is the quite bulky construction of the mechanism..

Mounting the PF-XL directily on the LA... hm, I do not like this, puts some uneven weight onto them.

fW

[Alasdair Ryan]

to get a nice looking system you would need to use something like blakbird posted with a driven tele axle or a micomoter but it also could be done using the m moter or xl moter but just not as good looking

[efferman]

4 actuators, 5 studs wide, at the base of the actuators 6 studs wide.

want anyone pics?

[freakwave]

4 actuators, 5 studs wide, at the base of the actuators 6 studs wide.

Great construction! Very slim and space saveing solution! like it!

[efferman]

thanks, i hope it could lift a relevant weight.

i have made a few pics

more can you find here when the folder is public again

[Milan]

Great, efferman!

I wonder how much it can hold and lift with one XL.

[efferman]

it works too with a M, but the noise of the M is a little bit stressed. the gears are producing in the current a little bit much resistance, so i have used the XL for the vid

[GuiliuG]

Do you use the old or the new linear actuor?

Actually great construction

[efferman]

the old ones.

[efferman]

ok, i have tested it and the lifting capacity is my Kat 7to mil gl (nearly 1 Kg) before the first 12 tooth Bevel Gear cracks. My conclusion of this is, that a rock solid transmission is required to get the payload from the ground.

[Erik Leppen]

4 actuators, 5 studs wide, at the base of the actuators 6 studs wide.

want anyone pics?

This is almost exactly what I did in one of my mobile cranes (not uploaded yet), but the problem with this is that the very long gear train consumes a great part of the energy, so it's not very much stronger than using just two parallel LAs. Also it's quite hard to combine with other functionality alraedy going through the boom axle (e.g. an extension mechanism).

[efferman]

i agree. next i will test this combination. if you and i right, it will lift my trial truck easier