darsedz

I want to use oil for hydraulic systems,maybe some low viscosity oil, actually I'm looking for it

I also finished some first attempts, but it's disappoints me. Lego valve need a rather lot of torque to switch it and I thinking on usage some simple self-made check valves instead of. It’s non Lego solution but…maybe enough to start thinking on rest of circuit.

soo... - next suggestion is a car lifter, with powered up/down control, something like...

yes, because on picture you can see bottom side of this structure, a top will be couple of flat panels with 4 wheels and rope

I tough about something like this above, on Lego stand there is a small spool of rope to hold a powered car

bottom side of some demonstrator stand, powering whels of red car?

look for some solution on Effe's corner (post 578) http://www.eurobricks.com/forum/index.php?showtopic=60459&st=575#entry1424871

To be honest - I thought more about what I needed to improve in my MOC's ;)

first vote for cussco is from my side :-)

Excellent design, nice tank finish, breaks on front wheel… shaft+cardan type of transmision like in my BMW. looks like extended ver. of 8051B - with next level of detailing...:)

You mean rubber on sterring beam (?) minifig handle has two grippers and one is inside this rubber... but it's a rubber piece so - for me it's ok. I looked for some idea to realize handle (not sure it's a correct word)...

let me introduce... brick version of BMW some minor changes made to increase rigidity (most corrected in LDD file), few small bricks still not inserted (looking for it), some changes in colors (due to unavailability of bricks in specific color, e.g. sit elements and engine body)... ... and next project in WIP phase... ;)

Lego Air tank has two inputs, thus can be used as oil tank or accumulator. The tank requires leaving one entrance open, facing upwards. Through this output container will be able to "breathe", to compensate for lack of oil - by the air from the atmosphere. Remember volume of oil in cylinder changes, in relase to position of piston, From min_vol = stroke * (Area_piston - Area_rod) to max_vol = stroke * Area_piston Level of oil in tank depends of actual configuration of pistons. Airtank (working as accumulator), placed behind "pump" will help to "stabilize" flow. Of course, to do that some amount of air must be inside of accumulator (like on standard hydraulic gas accumulators). I'm really thinking to test that, in real devices, just to have more practice... but it requires investmens ;) update... Stuff ordered, without airtank (it's expensive and rare)... so tests soon ...;)

Jim, what you mean "Power tools" for mini contest.. like e.g. drill machine, pneumatic compressor?

yes, maybe, but... we need a tank, able to accommodate pumps (Lego don’t have it, need gluing bricks) if tank is open = dust, dirt liquid, splashes…. My proposal it’s a closed system, ready to implementation and expansion or modification (cylinders selected depends on system needs), system easy implementable into vehicle, with fluid not exposed to environment…

Yes, as I mentioned - we need two valves for control of direction of flow from and into the cylinder. Valves must be switched on endpoint of cylinder. The Lego valves looks like 3/2 type vales (3 way, 2 positions). Some concept of "mechanical" part shown below, without a pneumatic elements (LDD don't have it), so some of dimensions will be different. Two cylinders working in opposite directions, driving by 2 gears (maybe smaller?) and electric motor. Valves switched both simultanously by traveling pins on gears. I'm not sure about leakage, but it's depends to fluid used in the system, I suggest hydraulic oil, maybe low viscosity, but this really needs a tests. I'm thinking on ordering thouse elements it and do some tests. We have also some test equipment (pressure / flow sensors and amplifiers) so some test on field can be done, if concept will work ;) The same principle can be realized by 4 check valves (but LEGO don’t have it) connected similar to "Greatz bridge", such installation will work "automatically" (in our laboratory we have installation with 3 or 5 cylinders, working as a pomp for small hydro power plant, driving hydraulic motor and generator).

The simplest idea to do a good working hydraulic pomp is usage of double side acting cylinder and two valves with control depended on direction of piston movements. One of valves will be responsible to switch direction of flow from tank (to suction side of cylinder), second valve will change a flow from active cylinder chamber to an output (as pomp output). To increase volume efficiency system like “boxer engine” will be used. Max pressure will be limited by max force on cylinder road and it area of active piston side. Maybe additional air tank will help to “stabilize a flow pulses”. Bigger pumps (3-5 cylinders) will be designed as like “stars structures”, min. section of holes in a system will limit a max flow. Similar method with double side cylinders and two valves can be used on actuators. I don’t have experiences in LEGO pneumatic systems, idea is based on 15 years experience in industrial pneumatics and hydraulics (servo control as well)

Hello again, thanks for your comments. Brick model is planned, LDD is a good tool for modeling but a great fun is a real assembling, especially for MOC, even just to check all solutions in this unique concept :) Due to some unavailability of brick in LDD (like front suspension) I used some combination of brick instead, final decision will be made with real bricks. Frame shortening (about 1M) is I think still possible, but parts like engine, gear box and few other brick limiting an area of solutions. What I also planned is another few panels into bottom sides of tank (with white or grey panels style like 6022768/6022767 – my LDD don’t have it). I hope show some results will be shown within few days… Darek Not tested jet... maybe some limiter will be needed...

Hello, My first post here, first MOC and first serious project in LDD... 40+ Lego fan, engineer… Inspiration: 1) custom BMW R100 http://www.bikeexif....bmw-r100-kevils 2) boxer engine and Cardan transmission 3) high prices for Lego chain elements ;) Some pictures shows final (??) result of transferring this beautiful bike into Lego Technic world… to be serious third attempt, lot of modification done during feew days of design ;) Selected ideas for this project tested in real bricks, to check rigidity and technical details. Real model - in future planes. ~ 360 elemets used, bricks only avaliable on LDD 4.3. Ready to Lego CUUSCO ;)? Thx for visiting topic Regards / Pozdrawiam Darek