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I wanted to make a small scale supercar model in the same scale as the Corvette. The TC18 was a perfect excuse to make a model with the following functions: 4 speed gearbox full working suspension a fake V8 engine working steering wheel openable doors Here is what I managed to create in LDD, inspired by the set 42111. I wanted to style the car like a 70's muscle car, so the fenders are brick-built to get the sharp lines needed. The final car is 40 studs long and 15 studs wide (excluding the mirrors). All of the described functions are implemented, the car is currently made out of around 900 pieces. I will post the WIP pics of the real build as soon as I start it. -
Hi all :) I've been building a good number of best supercar mocs lately, and i decided to step up my game a bit, and build a supercar (1:10) of my own. If the paneling, steering, making a chassis is Something i can do without too much trouble, it's not the same when it comes to gearbox. As i Don't want to rehash somebody else's job, or at least not completely (lol) i've been busy these past few days trying to learn how gearing works. And thx to sariel and his work, (e.g gear calculator / tutorial) i've learnt a lot already. But obviously, i'm just beginner and there is a lot i have to figure out before i can do a gearbox of my own. So i've build this one, found on internet and try to study it: I was trying to calculate gear ratio of each gear but i'm already stuck :( So question, since i can't even figure out which one of the entry is the input, hence the other being the output. Isn't a gearbox supposed to gear up whatever the gear engaged? so we'd have at the end Something like this, say: 1st: 1:6 2nd 1.4 3rd: 1.2,1 and 4rth: 1:1 (not related to the picture below) When i look at that exemple and the placement of the 1st gear, hence orange entry being the input, it appears to gear down, and hence, i've considered the red entry being the input. I'm already lost. And worse: i can clearly count that i have a 1:6 gear ratio, but when i try to calculate, the result won't match (4th gear on the picture): 24 teeth into 8 teeth: 1:3 8teeth into 16 teeth 2:1 Following grey 16teeth on a different axle is idle 16teeth into 8teeth 1:2 final ratio with math: 1:3 (calculator) but when i count 6 révolutions for the last gear, so i'should have a 1:6 ratio What am i missing here? thx for helping me guys! Sorry for the noob questions, but everything's gotta be a lot easier once i figure this out :)
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Here I present a 256 speed gearbox controlled by 8 switches. This design is based on a 2 differential N to P gear ratio design presented in one of my other videos. The gearbox allows 256 different gearing ratios to be selected. -
Here's my previous transmission design equipped with a torque-sensing shifter. The result is that the transmission starts at 4th speed and shifts down lower the more resistance the output meets. It's not perfect, the shifting is jerky because of a "gap" when both transmission rings are disengaged, but it works. I'm hoping somebody can improve on it and make it shift more smoothly. And the original transmission with instructions: -
I recently published my findings on using a sprung differential as a torque converter. I believe I have proved that a simple combination of a pb&g motor and a differential can amplify the pb&g's spring action down the drivetrain to compensate for a resistance on the wheel assembly. I would like to ask for some help with this. My mechanical engineering knowledge is topped out, and I'd really like to continue exploring this. Let me know if you have any ideas, more formal collaboration would be appreciated also. I'm looking at combining this torque converter with existing gearboxes, and also exploring its response at different speeds. http://imgur.com/gallery/IRGFReN -
Hi all, a while ago I posted about my 63 speed gearbox MOC using 6 switches and some people here asked for build instructions. These are now available on Rebrickable for those interested https://rebrickable.com/mocs/MOC-40533/TechnicBrickPower/63-speed-gearbox-including-reverse/ youtube:
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I finally took the time to write down the things I have come to understand with regard to LEGO 4-speed sequential gearboxes. I am receiving many questions about gearboxes and I hope these understandings can help you reason about a gearbox layout while you're building one or trying to design one. I hope this also answers a question I received from @nerdsforprez more than a year ago, which I did not answer yet. Gearbox layout Let's take a look at this 4-speed sequential gearbox layout. Black is input, red is output and orange is control. The main input is divided over a high input (black) with high input ratio and a low input (white) with low input ratio. The high input ratio is 1:1 (via a 12:12 mash) and the low input ratio is 1:2 (via a 8:16 mash). This makes for a combined ratio of (1:1) : (1:2) = 2:1 between the high and low inputs. I will refer to this ratio as the primary ratio. In fact this ratio is the ratio between the two driving rings. Both driving rings have a high output (green) with high output ratio and a low output (yellow) with low output ratio. For both driving rings, the high output ratio is 1:1 * 2:1 = 2:1 (via a 16:16 mash and a 16:8 mash) and the low output ratio is 5:3 * 1:2 = 5:6 (via a 20:12 mash and a 8:16 mash). This makes for a combined ratio of (2:1) : (5:6) = 12:5 between the high and low outputs of each driving ring. I will refer to these ratios as the secondary ratios. Rotary catch and quadrants Even though I will explain things in terms of the gearbox layout described above, the first understanding I want to address, applies to practically all 4-speed sequential gearboxes with 2 driving rings. Let's take a look at the rotary catch and driving rings from above and divide the layout into four quadrants. Each quadrant represents one of the four gears of the 4-speed gearbox. When we turn the rotary catch clockwise (seen from the left) with 90-degree steps, it will always make the following path through the four quadrants. From the path the rotary catch draws, we can see that it toggles from one driving ring to the other driving ring for every 90-degree step. So if we want to obtain a useful gear sequence (either a 1-2-3-4 sequence or a 4-3-2-1 sequence) along that path, we need to tie gears 1 and 3 to one driving ring and gears 2 and 4 to the other driving ring. Otherwise the rotary catch can never 'toggle' between subsequent gears. Now let's take a look at all distributions of the four gears over the four quadrants that meet this requirement. Starting top-left, this will produce a 1-4-3-2 sequence. Repeating the sequence will give 1-4-3-2-1-4-3-2-etc., which effectively boils down to a 4-3-2-1 sequence. Starting top-left, this will produce a 1-2-3-4 sequence. Starting top-left, this will produce a 3-4-1-2 sequence. Repeating the sequence will give 3-4-1-2-3-4-1-2-etc., which effectively boils down to a 1-2-3-4 sequence. Starting top-left, this will produce a 3-2-1-4 sequence. Repeating the sequence will give 3-2-1-4-3-2-1-4-etc., which effectively boils down to a 4-3-2-1 sequence. Starting top-left, this will produce a 2-3-4-1 sequence. Repeating the sequence will give 2-3-4-1-2-3-4-1-etc., which effectively boils down to a 1-2-3-4 sequence. Starting top-left, this will produce a 2-1-4-3 sequence. Repeating the sequence will give 2-1-4-3-2-1-4-3-etc., which effectively boils down to a 4-3-2-1 sequence. Starting top-left, this will produce a 4-3-2-1 sequence. Starting top-left, this will produce a 4-1-2-3 sequence. Repeating the sequence will give 4-1-2-3-4-1-2-3-etc., which effectively boils down to a 1-2-3-4 sequence. Surprisingly, every distribution that meets the requirement, will produce either a 1-2-3-4 sequence or a 4-3-2-1 sequence. What this tells us, is that it's enough to tie gears 1 and 3 to one driving ring and gears 2 and 4 to the other driving ring, to obtain a useful gear sequence. Nothing else matters! Primary ratio vs. secondary ratios The next understanding I want to address, concerns the relation between the primary ratio (the ratio between the high and low input) and the secondary ratios (the ratios between the high and low outputs of both driving rings). We have already seen that in the gearbox layout at hand, the high and low output ratios are the same for both driving rings. One thing we can say about 4-speed gearboxes in general, is that the ratios between gears 1 and 3 and between gears 2 and 4 need to make a bigger difference than the ratios between gear 1 and 2 and between 3 and 4. Now when we take into account that gears 1 and 3 need to be tied to one driving ring and gears 2 and 4 need to be tied to the other driving ring, and we use the same high and low output ratios for both driving rings, we can say that the secondary ratios, which constitute the ratios between gears 1 and 3 and between gears 2 and 4, need to be bigger than the primary ratio, which constitutes the ratios between gears 1 and 2 and between gears 3 and 4. The gearbox discussed in the beginning of this post has a primary ratio of 2:1 and secondary ratios of 12:5, so it meets the above requirement. Check! Swapping and reversing If we go back to the distributions we listed above, we can see that half of them generate a 1-2-3-4 sequence and half of them generate a 4-3-2-1 sequence. When we study them more thoroughly, we can see that all 1-2-3-4 distributions have a horizontally flipped counterpart with a 4-3-2-1 sequence. In other words, if we flip the distribution horizontally, we reverse the gear sequence. Example: Swapping 1-3 with 2-4 in a 4-3-2-1 sequence produces a 3-4-1-2 sequence. Repeating the sequence will give 3-4-1-2-3-4-1-2-etc., which effectively boils down to 1-2-3-4. Example: Swapping 1-3 with 4-2 in a 1-2-3-4 sequence produces a 4-3-2-1 sequence. What this tells us, is that when we mirror the gearbox layout left-to-right (top-down in the quadrants), which boils down to swapping the high and low inputs, the effect is that we reverse the gear sequence. Practical value: If you find yourself in a situation where you want to swap the upshifting and downshifting directions, simply swap the high and low inputs, like in the image above. Finally, if we take one more look at the gear distributions above, we can see that when we swap gears 1 and 3 or gears 2 and 4 in any distribution, we get a distribution with the reversed order. 1-2-3-4 will produce 4-3-2-1 and 4-3-2-1 will produce 1-2-3-4. When we swap both gears 1 and 3, and gears 2 and 4, we reverse the order twice and get again the same order. Example: Swapping 1 and 3 in a 1-2-3-4 sequence produces a 3-2-1-4 sequence. Repeating the sequence will produce 3-2-1-4-3-2-1-4, which effectively boils down to a 4-3-2-1 sequence. Example: Swapping 2 and 4 in a 1-2-3-4 sequence produces a 1-4-3-2 sequence. Repeating the sequence will produce 1-4-3-2-1-4-3-2, which effectively boils down to a 4-3-2-1 sequence. Example: Swapping 1 and 3, and 2 and 4 in a 1-2-3-4 sequence produces a 3-4-1-2 sequence. Repeating the sequence produces 3-4-1-2-3-4-1-2, which effectively boils down to a 1-2-3-4 sequence. What this tells us, is that when we mirror one side of the gearbox front-to-back (swap the high and low outputs of one driving ring), we will reverse the gear sequence. When we mirror both sides front-to-back (swap the high and low outputs of both driving rings), we won't affect the gear sequence. Practical value: If it's more convenient for the rest of your build to mirror your gearbox layout front-to-back, like in the image above, you can do so without any consequences. If it's more convenient to mirror only the left side or the right side of your gearbox layout, you need to also swap the upshifting and downshifting directions. If you want to inspect the gearbox used in this post in 3D, here it is in Stud.io format and here in LDD format. -
I decided to UP the things with my take on the 8081 modification contest. Here's what I came up with: Driven and steered front axle with homeage to the original design Tandem live rear axles working on a simillar prnicipal as the front axle Differential lock Two speed gearbox Working steering wheel You can see a sneak peek of the progress made in LDD:
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So here's the latest project I have been working on. I am actually waiting for 5 parts to arrive (4 tiles on the "boomerang" at the bargeboards and the exhaust in flat silver instead of LBG), but otherwise it is finished. I tried to recreate a F1 car with 2019 specfications with "typical" Red Bull stuff in mind (rake and pullrod in the rear for example). I took some liberty here and there. All the freaking winglets on these cars in real life+Technic=meh. So I went for a pretty basic flow of panels and wings. Another reason I also took some liberty was because trying to find blueprints or other good images for size reference of the 2019 or even 2018 cars were hard to come by for any of the teams. Or I just suck at searching, but I'd find it understandable if it is actually hard to find, since teams wouldn't want that stuff public. 20190921_135837 by Appie NL, on Flickr Functions are: - 8 speed gearbox (used didumos' and JB70's revised Chiron gearbox again, that I made 3 studs shorter again) with V6. - HOG steering through the T-cam and working steering wheel - Pushrod suspension front, pullrod in the rear - Had to sacrifice the driver's seat for a very basic gear selector mechanism due to lack of space elsewhere. 20190921_135940 by Appie NL, on Flickr 20190921_140038 by Appie NL, on Flickr The point at which the nose goes from angled to flat is too far towards the front of the car compared to real life, as the curving point tends to be right above the axle of the wheels. I am aware of this, due to the suspension setup in that section this was the best I could do. 20190921_140228 by Appie NL, on Flickr The diffuser isn't looking too good from this angle, the only good angle is looking right into the rear of the car. Couldn't figure out a better one with the limited mounting options in that section and the diff+suspension. 20190921_140301 by Appie NL, on Flickr 20190921_140342 by Appie NL, on Flickr In case you were now going: This belly shot sucks! Got you covered! (pun intended :D) 20190921_140422 by Appie NL, on Flickr I wanted to make a similar floor at first for my Rolls too, but dropped it because I am not going to be flipping that model very often to show the belly. And having to uncover it too after flipping, would be troublesome on that model. 20190921_140610 by Appie NL, on Flickr Close-up of the pullrod suspension in the rear and my crappy DRS system. Due to lack of space to route some controls for DRS to the cockpit with a diff, suspension, V6 and gearbox blocking alot of the way, I opted for this instead. 20190921_140645 by Appie NL, on Flickr Should have angled this pic more on the cockpit, but oh well. T-cam for HOG, yellow knob gear in the headrest is to flip the gears. 20190921_140956 by Appie NL, on Flickr Since Red Bull is known for the rake they have on their cars I had to mimic that too. It's a small angle, but it's there and pretty close to real life I think. In case you wonder, the car weighs about 1.7kg. -
Hi everyone ! Today I'm glad to present my latest creation : a replica of a Le Mans Prototype, the Lola Aston Martin ! See below the result, I worked on this creation during 1,5 month : SPECIFICATIONS : - Fake V12 engine - Independent pushrod type suspensions - Steering by HOG + Working steering wheel - 4 speeds sequential transmission + paddle shifting - Rear cover articulated - Elytre openable doors DESIGN : I used this part https://www.bricklink.com/v2/catalog/catalogitem.page?P=24118#T=C from 42056 Porsche to create the cockpit front curved shape. Into the cockpit you can find some details sport wheel and seat. The dashboard include speed indicator serigraphed tile but also green/red indicators to speeds shifting. Paddle shifting is created by 2 short yellow liftarms. You can notice presence of a red extinguisher ! Red and white pins indicate two sides of the paddle shifting ! FEATURES : To create the HOG, I used one couple of knobs and one couple of 16t. A friction axle avoid steering free wheeling. In other hand, doors are openable. For the rear cover, I used Nathanaël Kuipers tips to keep it open with friction like NK03 (https://www.nkubate.com/predator-supercar/) The fake V12 engine is a Crowkillers design : https://bricksafe.com/pages/Crowkillers/mini-v12 The sound it makes in functions of speeds is awesome ! Supensions pushrod system is a copy slightly modified of 8674 set. For the front pushrod I re-used Nico71 design like on his own LMP1 : https://www.nico71.fr/lmp1-racecar/ I created my own 4 speeds gearbox for this model. It's a flat design like 42056 Porsche one but there are less gears so less friction. I use blue rubber for the 90° indexor. See how its works in the video bellow. Ratios (without diff) : 1 : 1:1 2 : 1:1,667 3 : 1:3 4 : 1:5 I put a paddle shifting in the back of the car to up and down gearbox speeds. I re-designed 42083 shifter to make it smaller. MODULARITY : Main assembly is easily operate by a modular design. There are 6 modules and 2 structural elements. Cockpit itself is a part of main structure. I choose this kind of design in order to make instructions in the future. VIDEO : INSPIRATION : I'm sharing links of creations that somewhere gave me ideas for my Moc : https://www.hellobricks.com/2017/01/porsche-919-le-mans/ https://pikdo.biz/p/kimkamza/2048722475702589051_176999168 https://www.flickr.com/photos/158776396@N06/32215776147/in/album-72157676668829937/ https://www.eurobricks.com/forum/index.php?/forums/topic/138348-porsche-962-c-le-mans-racer-in-185/ http://www.techlug.fr/Forum/viewtopic.php?f=5&t=10823&start=45 I hope you'll like it See full HD gallery on Flickr : https://www.flickr.com/photos/147164115@N07/albums/72157712427943327/with/49298358508/ See you ! -
The idea of @nicjasno in for a gearbox can be improved as follows. There is no need for a 24 or 28 gear with clutch: the setup can be built as (two axles) 28-24-(20 with clutch)-clutch-(16 with clutch) (16 with clutch)-clutch-(20 with clutch)-24-28. For these gear combinations, a distance of 44/16=2.75 studs is desired. By using the above configuration, there is a distance of sqrt(2^2+2^2) or approximately 2.828 studs. This can be improved by xx -> 1 x 2 technic brick with 2 holes with axle at the left xxxx -> 1 x 4 technic brick with axle at the right. Then the distance is sqrt((3*2/5)^2+2.5^2) or approximately 2.773 studs, which is much closer to the desired 2.75 studs and then the gears run much smoother. -
I am still looking to tweak a few spots (the panel at the rear window is included in this), but mostly it is finished: 20190827_134133 by Appie NL, on Flickr 20190827_134604 by Appie NL, on Flickr 20190827_135244 by Appie NL, on Flickr 20190827_134945 by Appie NL, on Flickr I don't think I mentioned this before, but the "gas" and "break" pedal function as the forward/neutral/reverse for the gearbox. If I did the math right, then the reverse gear ratio is slightly above the ratio of the 2nd, perhaps not very realistic since afaik they are usually around the ratio of the 1st, I couldn't figure out a better ratio in the space I had left for this. 20190827_134741 by Appie NL, on Flickr 20190827_135042 by Appie NL, on Flickr The white levers with silver knobs control the windows and the black one on the dash controls the airconditioning. The lever below the steering wheel is for the lights. My aim was to have the positions for these controls as close to what they would be in a real car. Despite the roof being open, the front window levers are a little hard to reach for my big hands (especially with my left as you will see in the video below). 20190827_153707 by Appie NL, on Flickr 20190827_135520 by Appie NL, on Flickr My attempt to recreate the "star filled heaven" roof lining of the real Phantom. These are "glitter bricks". They only come in weird colours like dark pink until a set of Harry Potter brought these light blues. I considered adding PF lights to this for extra effect, but it didn't have the desired result in terms of lightning and I didn't want to use 3rd party stuff on this build. 20190827_134306 by Appie NL, on Flickr 20190827_134407 by Appie NL, on Flickr 20190827_135313 by Appie NL, on Flickr Behind the back of the trunk is the gearshifter from Attika and some wires. 20190827_140703 by Appie NL, on Flickr Perhaps looks a little bright in this picture, but there's only 2 PF leds per headlight on these. 20190827_140547 by Appie NL, on Flickr And the taillights, 1 PF led each. 20190827_140944 by Appie NL, on Flickr @Attika Here's your desired belly shot I don't have the new wire holders yet from Control+ sets and not sure of these can even hold 2-3 wires in 1, so I made something myself to hold/tunnel/guide the wires. At first I wanted to completely cover up the floor and "hide" the Technic like I mostly did on the rest of the car, but decided to keep it open. And some might notice that I updated the front suspension. When I nearly finished the build it needed an upgrade to 3 hard springs, same number as the rear, since the front suspension was pretty much dead in the old configuration. And a little video to showcase the windows and airconditioning Original opening post below this point: With all the great sportcars on this forum, I felt I had to try a different approach to the "1:8 Lego supercar". Choosing this car also gave me a good excuse to add different kind of functions usually not in these kind of cars. First of all I want to say thanks to a few people on this forum for information, techniques or mechanisms they provided: @Didumos69 and @jb70 for their work on the Chiron gearbox. This model uses their efficiently build Chiron gearbox, I only tweaked it slightly further to make it shorter. Also thanks Didumos and @Erik Leppen for their information on suspension, made it easier to look for how to fix stuff. @Attika for his compact servo based gearbox stepper which I used in this model. @Jeroen Ottens for all sorts of neat techniques and tricks in his DB11. The front mounting of the suspension is very similar to his to get the engine very low like in his DB11. I am sure I forgot a few people, my apologies. So here's the current progress: WIP3Frontside by Appie NL, on Flickr WIP3RearSide by Appie NL, on Flickr WIP3Side by Appie NL, on Flickr The current features are: - 8 speed gearbox - V12 fake engine - Suspension - Electric windows - "Airco" - Lights I think, despite the outer shell being about 70% system bricks and 30% technic, the base of the car is all Technic and that it should belong in this forum and not the scale forum. This is how the car looked in the early stages: WIPRollsPhantomFront2 by Appie NL, on Flickr But if Jim or Milan thinks it should still be in the other forum, I am sure he will move it. The reason for the mostly system outer shell is because I had a hard time making all the little curves with Technic (panels) and I felt those little curves made the difference to try and capture this car. Especially at the front, after that I tried to minimize Technic panel use because it would be a breach of style at that point. Overall I am happy how it turned out so far, some parts I don't like. The windscreen being the biggest offender with how square and flat it looks, but the A-pillars being part of the structural integrity of the model made it hard to come up with something else. Stuff left to do: - Dashboard and midconsole - Front seats - Roof - Mirrors - The bottom 2 studs of the model (under the doors, bottom of front grill and the second layer of the floor to hide wires and provide more rigidity to the model)
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Hey everyone, Here's my newest MOC, the Audi Quattro group B rally car. Hope you guys like it! Final by Teo's Technic, on Flickr It has -working steering with servo motor -4x4 drive with 2 x L motors and independent suspension -two speed RC gearbox -headlights -opening doors and hood. DSC06195 by Teo's Technic, on Flickr DSC06203 by Teo's Technic, on Flickr Final2 by Teo's Technic, on Flickr DSC06198 by Teo's Technic, on Flickr -
Hi All, I have created a new design for a 2 speed automatic gearbox that is both smoothly switching and compact. The best of both worlds. I don't know if my new (for me) technique has been used before so welcome your feedback.
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This video presents a 3 speed automatic gearbox design that failed to work as expected. This design is based on an earlier design of a 2 speed smoothly switching automatic gearbox that worked very well. That gearbox was extended by adding another speed to the rotary catch selector however something happened I didn't expect.
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Hi everyone. This is an efficient 4-speed gearbox design I came up with a while ago using the wave selector and new(ish) 20-tooth clutch gears. It is efficient since only 8 gears and 3 rotating shafts are required, which is near the minimum possible. The shafts in the image are as follows: Yellow - output Red - input Orange - shifter Black - extra, free-spinning All of the shafts go straight through the gearbox. The compact design is possible by meshing 16-tooth and 20-tooth clutch gears, which gives different ratios at each of the 4 clutch points. Unfortunately, the two shafts with driving rings need to be connected by another gear mesh (in this case 12:24) which results in out of order shifting with the wave selector. Gear 1 (1st) – 12:16 + 12:24 = 8/3 = 2.67:1 Gear 2 (3rd) – 12:20 = 5/3 = 1.67:1 Gear 3 (2nd) – 16:20 + 12:24 = 5/2 = 2.5:1 Gear 4 (4th) – 16:16 = 1:1 The shifting order issue could be corrected by using a mechanism shifting one driving ring back and forth and then the other, but that would take more space than the wave selector. The offset of one driving ring by one stud is handled by a sliding 16-tooth gear linking the lower driving ring with another 3 studs higher, putting it in the proper position to mesh with the wave selector. The extra free spinning shaft (black) is used to hold the third driving ring. The transmission fits into a small 9x7x6 box (not including the stepper) which can be easily connected to a chassis represented by the 5x7 frames. The below picture shows how small the core part of the gearbox is. In conclusion, the advantages of this gearbox include small size, few moving parts, and different ratios, while out-of-order shifting is a disadvantage. Comments and questions are welcome -
Here I present an 8 speed gearbox that does the seemingly impossible - creating eight speeds using just two levers/selectors. Normally two selectors are used to create a 4 speed gearbox - however this design allows for 1 of 8 different speeds to be selected - thanks for the idea @SNIPE
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Hi for those interested I have put the build instructions for my "smoothly switching automatic 2 speed gearbox" on rebrickable: https://rebrickable.com/mocs/MOC-51030/TechnicBrickPower/smoothly-switching-2-speed-automatic-geabrbox/ Here's the video about it:
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Here I present a smoothly switching 2 speed automatic gearbox. The gearbox uses the "differential jam" phenomena to prevent reverse torque transmission during the gear switch over point, when the driving gearing can be momentarily disengaged. The gearbox automatically switches down by a ratio of 2/3 when the load on the output is sufficiently high by using a differential to detect the loading and to drive an orange rotary catch. This is a smooth transition due to the reverse path being only one directional. https://youtu.be/h7j50GRm6Vc
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Hi everyone, Lately, I read topic on Audi R8 from Jeroen Ottens (https://www.eurobricks.com/forum/index.php?/forums/topic/178368-wip-audi-r8/) and it remembers me that I had such a prototype of a sequential gearbox. It's an improved version of my sequential gearbox used on my Bugatti Chiron 1/8, lighter and more compact. I use 4 orange rotary changeover selectors. I just want to say that is only a prototype version unfinished that I wanted to share with you. Please do not judge assembly design, but system core. How does it works ? - The main shat is the center one and it's made the dual clutch shaft - On each side, there is 1 half-gearbox. One with odds speeds (1, 3, 5, 7) and the other one with even speeds (R, 2, 4, 6). - On main main shaft, there is an offset of 90° between the 2 orange changeover. Its engage only at time one of the half gearbox. The real secret of the gearbox is the offset between each half gearbox. I used a factory wheel with 2 pins with tow ball to create this offset. See the picture below : Of course, the gearbox has a end stop to prevents 7 to Reverse shifting. Ratios ; R : 1,2 1 : 0,6 2 : 0,75 3 : 1 4 : 1,67 5 : 1,8 6 : 2,1 7 : 3 The reverse speed is too fast. I worked to an improved version too, smaller that prototype. The arrow shows the right way to shift up. Finally the video to understand the mecanism : I hope you will like it ! See you soon !
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Here I present my 12 speed gearbox design. The gearbox implements 3 reverse speeds, a stop gear (zero speed), and 8 forward speeds. The forward speeds range from 0.307 to 1.2 and reverse from -0.067 to -0.36. The gearbox has a single gear lever to drive two rotary selectors to select the gears. Let me know if you like it, have any comments or questions.
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Hi Everyone, I have created this 4 speed gearbox based on the "change over rotary catch" component and I have used it to select 1 of 4 gearing inputs in possibly a new way by connecting to four clutch gears which then connect to a differential housing used as a method to transfer motion whilst allowing the rotary catch to be rotated freely inside of it. The gearbox implements 3 forward speeds, and 1 reverse. I was wondering if anyone has seen this technique before (I am guessing yes since most ideas are not new)? Anyway thanks in advance.
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This is a compact 2 speed automatic gearbox design. Instead of using a differential to react to torque on the output it uses the force on the gear teeth to push a liftarm to automatically change the gearing ratio to the 2nd speed once the torque threshold has been exceeded. The automatic gearbox will switch back down to the first speed once the torque on the output is reduced by using two rubber bands to pull back the liftarm. The first speed is simply a 1 to one ratio and the second speed is a 0.6 ratio. The design can be easily modified to change the the second gear speed to other ratios such as 0.36 or 0.2.
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Hi Everyone, This gearbox has been designed to automatically reverse if there is a high load on the output. The gearbox works by using a differential to react to the torque on the output and it drives a two state switch to select the reverse or forward direction in the gearbox.
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This gearbox is an upgrade of my ultra compact 8-speed sequential gearbox. The 8-speed gearbox was nice but it was frustrating to know that the 2-speed gearbox took as much space as the 4-speed gearbox. I thought about transforming the 2-speed gearbox into a 2+N+R one. I had an idea about how to transform this gearbox but I didn't really think about how to activate the reverse and the neutral. Maybe by doing something with the knobs... I spoke with @Charbel and he gave me the idea to use the Bionicle parts I already used on my previous gearbox. Then I ended up with this: I used large frames as in the Lamborghini Sian. They make the whole gearbox stiff and now you have just to build a chassis arount the 'box! The neutral was extremely simple to do. See by yourselves: The reverse was more complex to create. For every foreward speed, the 2+N+R-speed gearbox rotates the 4-speed gearbox by the red 16t at the bottom. The reverse doesn't use the 4-speed gearbox, it uses the blue 20t at the top of the picture below: To engage the neutral and the reverse, I fixed two Bionible parts on the left knob. So they act as a smaller knob, with two teeth, and at a point 1/4 turn of the right knob makes the left knob rotate by 1/4 turn, whereas for all the foreward speeds, the left knob does 1/4 turn every turn of the right knob. Reverse engaged: Neutral: First: There is a stop not to shift from the 8th to the reverse. The engine and the gearbox wouldn't appreciate. The wheels have to be connected the the red axle and the engine to the grey one. It's possible to use this gearbox for a 4WD vehicle easily since the red axle goes through the gearbox. With this gearbox you don't have to use a 8-speed gearbox and a DNR one anymore, as in the Chiron or the Sian. It saves space, and you can't engage the 4th speed whereas you are in neutral - all the speeds shift into a logic order. I will make instructions when I have time!