Comments on: 2-speed Automatic Gearbox

By: Sariel

Sariel — Thu, 02 Feb 2012 08:50:17 +0000

@johnboy104 Probably.

By: johnboy104

johnboy104 — Wed, 01 Feb 2012 23:41:36 +0000

What about if your output dosen’t run to 180 rpm, will it be a hard shift then?

By: Sariel

Sariel — Tue, 27 Dec 2011 07:44:38 +0000

@wyatt Because it's way too fragile.

By: wyatt

wyatt — Tue, 27 Dec 2011 02:07:01 +0000

@Sariel More rubber bands?

By: wyatt

wyatt — Tue, 27 Dec 2011 02:05:28 +0000

why Wont you use this in your trial trucks?

By: Pepijn de Vos

Pepijn de Vos — Mon, 26 Dec 2011 13:45:46 +0000

Ah, nicely done. I tried several of these a while back, and my best one is this: http://wishfulcoding.nl/buildinginstructions/gearbox.pdf

By: Sariel

Sariel — Thu, 14 Jul 2011 06:11:46 +0000

@neamerjell There is a three-speed design of such a gearbox existing. The problem is, it rarely stays on second gear, and the problem would increase with more speeds.

By: neamerjell

neamerjell — Thu, 14 Jul 2011 02:52:36 +0000

@Sariel I figured the transmissions might try to work against each other like that. I wonder how difficult it would be to make an automatic transmission using the same concept as this one, but with more than two speeds. My first guess would be that the resulting size and complexity would make it impractical for use as anything but a proof of concept. Still, it would be a neat thing to try.

By: Sariel

Sariel — Tue, 12 Jul 2011 20:00:09 +0000

@neamerjell Yes, bevel gears are way better suited for linear gearboxes. As for coupling two automatic gearboxes, I think it wouldn't work well because they would keep affecting each other. They are both torque-sensitive and at the same time they manipulate the amount of torque in the drivetrain, so they would interfere with each other and probably keep switching back and forth all the time.

By: neamerjell

neamerjell — Tue, 12 Jul 2011 19:55:57 +0000

I’ve seen your stuff around Brickshelf.com over the past few years, and I’m completely blown away by the ideas you come up with.

What do you think would happen if you made a second transmission, with a different ratio, and its input connected to this transmissions output. Would it make a four speed automatic transmission, or would both parts try to shift at the same time when resistance is met?

Also, I’ve noticed when I tried to build linear transmissions with 24, 16, and 8 tooth gears, they end up grinding and binding. Do the bevel gears you used help with this?

By: shawn

shawn — Tue, 12 Jul 2011 19:25:15 +0000

I successfully built the transmission with the old differential.

By: Sariel

Sariel — Fri, 18 Mar 2011 17:01:05 +0000

@ghzz It can be the rubber band, or some pieces are put together too tight. Yes, the gearbox is supposed to work only clockwise.