How a differential gear works

[Executioner]

This is old video - 70 yrs, but it does a good job of explaining the basic principals of a differential.

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[normalicy]

That's cool, I already knew the concept, but I liked how they went through the engineering thought process in improving it over time. I'm sure they didn't use sticks to start with though.

[FlyingPenguin]

Very cool. Thx for that.

[Pugsley]

I was hoping to also see limited slip and posi.

[EvilHorace]

I'm sure they didn't use sticks to start with though

Never gave it any thought before but apparently you didn't make sharp 360 degree turns with a horse drawn wagon back in the day but then too, the roads were dirt so it wouldn't be a problem.

[normalicy]

Huh, I just figured that the axles weren't solid on wagons (i.e. each wheel spun independantly).

[Koo Koo Mouse]

Norm your right, no reason to have them cross connected if its pulled. The horse brain managment sytem takes care of all that.. Indepentant hoovement.

[EvilHorace]

http://en.wikipedia.org/wiki/File :E li ... canada.jpg

Don't know about all horse drawn wagons but the one pictured above has a front "axle" and probably a rear one too. "axle shafts" would have been needed to support each wheel as they'd be easy to hook up to the carriage, otherwise they'd need what we use today with front wheel drive cars that use rear trailing arms and then you'ld need to know something about rear caster, camber, toe, not required with a simple axle shaft.

More:
http://www.buggy.com/

http://www.google.com/images?q=horse+dr ... 80&bih=873

[FlyingPenguin]

We have a carriage museum here and yeah, the rear is usually an axle. On fancy carriages the front usually has a steerable front axle.

At the speeds a carriage is going, it's probably not an issue.

[normalicy]

Yes, they have shafts, but I'm under the impression that the shafts weren't rigidly mounted to the wheel. I believe there was grease between the shaft & wheel. Otherwise, I could see the torque buildup from a 5-6 foot wheel being able to snap such frail axles (heck, I've seen torque snap modern 1 1/4" thick hardened steel axles with smaller tires).


Here's about the only info I could find on axle build. Though, they aren't specific about what's being zoomed in on.

[FlyingPenguin]

Yeah, that makes sense. It'd be easier to make the wheels spin on the shaft rather than spin the axle.