The big gearbox thread! ^^

[sevs]

Looking for some ideas to gearboxes? Or do you have some? Write your heart out.

[dhc6twinotter]

Hey Sevs, welcome to the forum!

Are you referring to multi-speed gearboxes (transmissions) used in vehicles, or are you referring to the type used to control multiple functions, like the gearbox in the excavator?

Edited December 17, 2011 by dhc6twinotter

[allanp]

Here's a selection I made. I find the 4 speed and 5 speed + R to be alot stronger than what you find in 8880 and 8448/8466. The transpher cases are good for added functionality and complexity in 4WD/AWD MOCs.

Hope this helps.

[DLuders]

On his website, Sariel has a nice 4-speed Compact Linear Gearbox (with pictures and description), and this

:

He also did this 2-Speed Linear Gearbox:

[SNIPE]

This is all very intresting and claver, because you can use the diff with the gear internal clutches (not the cluch for the clutch pedal)

I made an internal clutch system that was able to have either the 6, 7+7th or 6th+7th +8th gear positions disabled., any input could be configured as A reverce gear, you just have to add what gears you want onto the ends of each clutch

The only difference is that to slide to another bay of gears you dont put the lever back in the middle, here is a diagrap of it, the blue liens represent the movement of the gear stick:

park ('P'). and '??' can be anything you want it you just have to add the right outer setup of gears. the example below is just my imaginary setup.

The clutches have teeth on them themselves for if you want to have a transter case or a low range box or a diff lock or more gears for something. the gears would normally attach to the end of each clutch (there is an axle either side of them.)

Here is the image:

The axles ca be moved aswell either by motors or by a shifter but id use this as an alternitive unless you want lots of levers or a large linkage system.

the clutches have housings over each one which have notches on the top, these notches are meshed with the gear leve which moves the clutch if you are not using the axle moving feature.

Edited December 18, 2011 by SNIPE

[Brickend]

Any proof that the above actually works....maybe in the form of a physical, implemented and complete gearbox?

[SNIPE]

there is no real life model I have made but it should work because there is only two essential parts, the axle and the clutch barrel that has teeth on it to link them together if engadged.

the spacers between the axle holders are part no '42446'

The axle hole just goes through these so keep the spacing of the axle holder bricks and the teeth on the barrels in place.

[Brickend]

Snipe, please build it.

I want to be proven wrong.

[SNIPE]

I would have to buy the parts and my mother does not like the idea of buying things from eurobbricks.com incase somebody scams me or something.

it sucks, I know

[timslegos]

I would have to buy the parts and my mother does not like the idea of buying things from eurobbricks.com incase somebody scams me or something.

it sucks, I know

what about bricklink.com?

I have placed almost 30 orders on the website and not one has been a scam at all.

tim

I would have to buy the parts and my mother does not like the idea of buying things from eurobbricks.com incase somebody scams me or something.

it sucks, I know

what about bricklink.com?

I have placed almost 30 orders on the website and not one has been a scam at all.

tim

[Alasdair Ryan]

I would have to buy the parts and my mother does not like the idea of buying things from eurobbricks.com incase somebody scams me or something.

it sucks, I know

Bricklink you mean?

Could you change the design of it in which you could build a replica of it?

[Brickend]

Snipe, if you finish the gearing and point out where the input and output shafts are, I'll build it.

As it is, I can't see how it can function. The right and left hand shafts are always running at the same time, due to the winches - I can't see a way to get 6 different speeds in there as the gears would be constantly meshed, but with different ratios.

It also looks like the spacing of the winches would be awkward for standard lego gears.

[SNIPE]

OK ill do that, im looking forward to seeing it work!

[nielsvdv]

this is a small 2 speed i made, i don't know if it is used before.

i made it for an rc model, i needed 2 gears and not too difference between gear 1 and 2.

the ratios are 1:2.5 and 1:1.536

LINK:

http://www.brickshelf.com/cgi-bin/gallery.cgi?f=448047

[SNIPE]

If you have questions about it please ask, I think in the below exmaple is:

1st = all three clutch gears meshed, the middle red axle meshed with the clutch, nothing else meshed at all.

I dont know for sure because I only just finished putting the external gears on, you'll have to experiment with it and see what happnes.

The middle clutches are obvioustly there for another set of configurations, this is good because it does not mean having lots of spcings between lots of external gears like on other models I have seen.

Normal clutches of a gearbox (not the clutch pedal clutch plate) dont mesh together, The axles with the axle joiners on are the input and output shafts (blue = to engine).

Here is the LXF file of the model:

Edited December 19, 2011 by SNIPE

[Splat]

A little while ago, I came up with these two gearbox designs:

These were designed for a specific purpose: 3 speeds plus a second output (PTO). You can read more about these in my original post.

I have been playing with some other gearbox designs too, and I hope to document and post them soon.

Edited April 10, 2013 by Splat

[Lipko]

I think the gear-shifting mechanism is more interesting than the gear system. I would love to see some designs for that! Designs for sequential shifting, or regular (H pattern) shifting but with non-common gearbox orientations/positions.

Tight packing of all the stuff is an interesting topic too.

BTW, I'm using the synchronized gear system for the 4 speed gearbox posted by Allanp.

[Bulle]

Also a fan of gear shifting mechanics in lego, any kind, all kind :)

[Brickend]

If you have questions about it please ask, I think in the below exmaple is:

1st = all three clutch gears meshed, the middle red axle meshed with the clutch, nothing else meshed at all.

I dont know for sure because I only just finished putting the external gears on, you'll have to experiment with it and see what happnes.

The middle clutches are obvioustly there for another set of configurations, this is good because it does not mean having lots of spcings between lots of external gears like on other models I have seen.

Normal clutches of a gearbox (not the clutch pedal clutch plate) dont mesh together, The axles with the axle joiners on are the input and output shafts (blue = to engine).

Here is the LXF file of the model:

Thanks Snipe. So far I have only found 2 of the reels that I need so I haven't tried the gearing. The part of the reel which actually engages onto the axle is off center by less than half a stud, which makes things awkward, but I do now see how you viewed this as working.

It is a nice curiosity and an imaginative use of parts but I am still not sure that it's low torque handling characteristics lend this design towards practical application. That said, the idea of the reel as a selector does work, which is something I didn't think would happen.

[basbase]

Good thread. I'd like to add my gearboxes:

which i described here

[TechnicJuan]

This is a unique gearbox. I have replicated it and can confirm that it works very well.

Pictures

[Sheepo]

Some months ago I was decided to develope a new gearbox base to use in my secuential gearbox family.

I was searching a compact gearbox silimar to the 8448 gearbox, but more efficient, strong and with more realistic speeds ratio...

Interestingly I get the same configuration that allanp with 5+R gearbox :laugh:

Great thread!!! keep it at top!!

Edited December 19, 2011 by Sheepo

[allanp]

Yeah, that gearbox hasn't given me one single gear teeth click in any MOC for 11 years since I first used it in Blue falcon

The gear ratios are:

R = 3.472:1

1 = 2.778:1

2 = 2.083:1

3 = 1.667:1

4 = 1.250:1

5 = 1.000:1

Which gives a nice and realistic, smoothish curve with the distance between gear ratios getting consistantly smaller as you move up through the gears. The gearbox in 8448/8466 on the other hand has ratios of....

R = 2.501:1

1 = 1.667:1

2 = 1.500:1

3 = 1.000:1

4 = 0.900:1

5 = 0.600:1

....which produces a very wobbly curve with the biggest ratio difference (ignoring reverse) happening between 2nd and 3rd with the smallest difference happening between 3rd and 4th. This gearbox is also prone to gears slipping due to some gears not being placed as close together as they should be.

Edited April 24, 2016 by allanp

[Splat]

I think the gear-shifting mechanism is more interesting than the gear system. I would love to see some designs for that! Designs for sequential shifting, or regular (H pattern) shifting but with non-common gearbox orientations/positions.

Tight packing of all the stuff is an interesting topic too.

BTW, I'm using the synchronized gear system for the 4 speed gearbox posted by Allanp.

I agree that the shifting mechanism is just as important as the gear system, and this is something that I have been trying to work on lately. I have been developing a gearbox with a linear selector that is remote controlled, so I have been playing with linear actuators, worm gears, gear racks, and even chain links to move the gear selector back and forward. The problem with my gearboxes is that the axle on the gear selector has to move back and forward out of the actual gearbox. This takes up a lot of room, and means the axle can also flex quite a bit, causing teeth to jump and grind.

If anyone else has interesting ways of shifting gears (preferably remote controlled), then I would love to see some examples (pics/vids).

Edited December 20, 2011 by Splat

[DLuders]

@ Splat: On his JurgensTechnicCorner.com website, Jurgen Krooshoop has (25-MB) PDF Building Instructions for his Lego Technic 4-Speed RC Gearbox that utilizes Power Functions: