I just meant the normal cylinders with two port. But instead of actuating them by a valve, I want to use them to generate a vacuum for a gripper. In order to do so I have to drive them by a motor, just as you would do with a pump, but this time a cylinder is extended and compressed by the pf motor. So in this case the cylinder is used as a pump, however it is generating the vacuum.

I think I'm getting where you are going with this. Correct me if I'm wrong. You are using the PF to power the Cylinder, which will operate the gripper. In other words; you will use PF to operate the gripper (technically). This is NOT allowed. PF can't be used to operate functions, even if there's a cylinder in between.

(although I do like the idea)

no its still a bit different. I tested this idea before. The motor revolves a cylinder and at the same time a valve is switched. If you connect the tubes correctly and switch the valve when changing the direction of motion of the cylinder you can create a vacuum. See a device i made which is used to make pavements: http://www.brickshelf.com/cgi-bin/gallery.cgi?i=5731642 I was able to lift my Samsung s4 by using this technique. It just reverses the process of a pump.

Edited August 31, 20168 yr by KvM

http://www.brickshel....cgi?i=5731642.

FTFY! Because you had a 'dot' on the end of the link. And it's bring me to an error page.

BTW, here is the full gallery!

Edited August 31, 20168 yr by KamalMYafi

so we are not allowed to operate a motor that drives a pump with a remote and a recever ?

so we are not allowed to operate a motor that drives a pump with a remote and a recever ?

No IR receivers.

You can start before the weekend

(or do you need all your LEGO for the weekend?)

Well, I'm in Germany at the moment but my LEGO is at home in New Zealand! All I brought with me was a small Technic R2D2 that arrived in the mail as I was leaving.

No IR receivers.

Why :( ?

Why :( ?

Because this is Pneumatic contest, not Power Functions contest.

Focus should be on Pneumatic functions.

Is it allowed to power a mechanical pto when the same motor powers at the same time a compressor?

Edited September 1, 20168 yr by efferman

A couple of questions related to PF. Is it allowed to use PF Switch to control motor? Lights may be used in combination with motorized pumps. Does it mean that lights only can be powered at the same time as motors? Is it allowed to use PF extension cables, for example in umbilical?

Is it allowed to power a mechanical pto when the same motor powers at the same time a compressor?

Hi Michael, sorry, but motor can only be used for a compressor.

Hi Michael, sorry, but motor can only be used for a compressor.

Thanks for clarification I was wondering same thing.

Anyone ever seen this?

http://www.youtechnic.com/home.html

Anyone ever seen this?

http://www.youtechnic.com/home.html

Nothing to see for me.

Anyone ever seen this?

http://www.youtechnic.com/home.html

Me? not!

But, isn't 3rd party part not allowed?

But, isn't 3rd party part not allowed?

True. 3rd party is not allowed.

Maybe I should post it somewhere else.

Anyone ever seen this?

http://www.youtechnic.com/home.html

I have seen something like it, this one seems higher quality though

Can I get a final answer on whether it is allowed to create a vacuum by driving a normal cylinder? Otherwise I have to come up with something else.

Can I get a final answer on whether it is allowed to create a vacuum by driving a normal cylinder? Otherwise I have to come up with something else.

No, sorry, it is not allowed. Motors can only be used to drive a compressor..

Your idea is great and unique, but it does not fit the contest rules.

Are we allowed to use the PF swich to control the motor that drives the pump ?

OK, if someone is interested, I can build a test setup to make the idea clear and allow you to test the vacuum system yourself.

For the contest I will find something else.

you will use PF to operate the gripper (technically). This is NOT allowed. PF can't be used to operate functions, even if there's a cylinder in between.

I don't think this argument is valid - I mean, a compressor is nothing but a cylinder with a valve instead of a top port.

It is certainly possible to construct a compressor from a normal cylinder and some switches (as I posted about a decade ago! http://news.lugnet.com/technic/?n=15434) - this construction also would be outlawed under the current ruling, even though it's functionally identical to (if vastly bulkier and less efficient than) a normal compressor.

In any case, KvM, I'd like to see what you were planning.

Owen.

Well yeah thats basically it. Although I made a version which contains only 1 switch.

A pneumatic engine (LPE) is allowed to be used when operated by a hand pump?

Edited September 4, 20168 yr by KvM

Are we allowed to use the PF swich to control the motor that drives the pump ?

Considering the alternative would be to have every entry with a battery box in the open or at least the battery box switch in the open, I would hope so?

At least I personally wouldn't like it if I couldn't turn off the compressor in an easy to get to place, might break something.

Are we allowed to use the PF swich to control the motor that drives the pump ?

Yes, switch for compressor motor is allowed.

A pneumatic engine (LPE) is allowed to be used when operated by a hand pump?

LPE is allowed, sure! You can power it with hand pump, or with a compressor. Just don't copy design from someone else 1:1.

Edited September 5, 20168 yr by Milan