The anti backdriving property is generally apparent with worm drives of greater than 5 to 1. 5:1 and less can be backdriven. Give or take dependent upon the coefficients of sliding friction between the worm and gear materials.
@ThinkingandTinkering There are rappelling desending speed limiters that are little more than 5:1 worm drives being backdriven with an air drag vane on the "input" shaft. Air drag provides the fast shaft speed limiting load.
Robert Thanks for the explanation. I once worked in US Army maintenance calibrating all the torque wrenches, multimeters etc. used by the repair crew on helicopters. One of the wrenches was used on the nut used to secure the rotor to the aircraft and was rated at 10,000 ft/lbs ( not sure what the metric equivalent is) of torque. We had one that could not be brought into spec so the boss let us look inside before it was sent to higher up the chain. The inside looked very much like what you demonstrated and I can only conclude that is how they obtained the power required for the torque. Thanks for the lesson.
Wow that was fast. Last episode I mentioned the Torsen diff and you have it made this episode. Torsen built a drive system that used 2 stacked rear ends where the one side was chain driven and the other side was gear driven 1:1. this allowed the lower rear end to be driven conventionally and conventional output to the wheels. The upper differential would perfectly differentiate and the ring gear would not move (input shaft not move). Then by driving the upper shaft left or right it would pass the change on to the lower drive. This was an idea to be used in tanks or other tracked vehicles to turn perfectly, at any speed, with out double transmissions or double engines that are conventional. Popular Mechanics back in High school Oh.... 40 yrs ago I'd say
My car has a Torsen differential and so I've always been a bit fascinated by how they work. I will definitely be printing your model soon, thanks for the great content as usual 👍
What's interesting is that Torsen's patent hardly differs functionally or conceptually from Maurice Walter's patent of 1914 (US1164769A). Walter's 1958 filing (US2972265) is even closer. What's old is new again! Maurice Walter's patents were used in his line of Walter trucks, perhaps most well known for his Sno Fighter plow trucks and airport crash trucks (fire trucks). His trucks were the eastern US answer to the midwestern FWD and subsequent Oshkosh trucks. Maurice was a New York candy maker, turned candy equipment designer, turned motor vehicle designer. His early trucks were actually license built versions of the French four wheel drive Latil. Maurice's improvements of "100 % Traction" differentials, combined with a final gear reduction at the wheels, made for tough, "unstuckable" trucks. Look here on YT of videos of Walter trucks plowing open roads through wind-packed 8 foot deep snow drifts on the Tug Hill Plateau in Upstate New York. Pretty amazing stuff. I would love to get me a Sno Fighter...
Technically, a coarse enough worm gear can be driven, it does require a lot of torque to do so. Also technically a worm thread is a single tooth in a spiral.and the thing that stops a worm being driven is friction. Thus for the locking mechanism of this system is that it's easier for both output shafts to turn at the same speed when free running. It is an elegant solution though.
My old GM truck has a "limited slip" differential. I'm not so sure about the name. It seems to be a diff that is limited because it slips on absolutely everything. The truck will get stuck on flat green grass in 4WD mode. I wonder how a Torsen diff would perform. 4WD is tricky because you have 1 power axle going to a transfer case (fancy diff) that powers 2 drive axles, each of which goes to an axle diff (pumpkin) that goes to 2 wheels. 4 wheels, 3 diffs, 2 drive axles, 1 power axle, and still going 0 m.p.h. :D
Remembering back to a Popular Mechanics back 40 yrs ago it said the 1 Torsion diff often was better than other types of diff's and was almost as good as 4WD. These diffs are used in airports on the tow vehicles used to tow the aircraft around. As long as one wheel has grip it will pull the plane
Back in the late 80's I had to trailer a 32' military boat ((I forget the weight) with a Gov't chevy Suburban. Every bump on the highway caused it to slip out of gear. I'd pull over, put it in park, put it back in 4wd and continue on to the next bump on the highway. Lather rinse repeat to infinity and beyond. Excruciatingly annoying trip at 50mph shuffling from Buffalo to Oswego NY. I chalked it up to the cheapo trend car manufacturers were resorting to in that era.
You forgot to try to hold one side of the differential while spinning the pinion shaft , both sides will lock. Another advantage is If the vehicle has one wheel on the air ,both wheel locks and the vehicle can still run.
This seems like a mechanical logic gate. The one way functions as your resistor! Its the AND function of the gears. Imagine the entangled complexity of the patterns of electron motion as these entangled gears interact at 2500 iter/s!
I'm not clear on if end narrow spur gears are fixed in position on each end of the long helical gears! are they both free to rotate? Or is one fixed & the other free to rotate? So, the free one mates with fixed one? What is the power path/loading capability?
That's a really interesting mechanism Rob! If you're going to use it backwards for two inputs to one output, what effect does their differing speeds have on the output? Like would it equalise the two inputs (split the diff) or would the higher speed input side determine the output?
Another great clear demonstration of brain-ache mechanics! Quick question... How do you stop Tinker cad grinding to a halt with such complicated designs? I often wait ages for their servers to catch up.
I try not to exceed 300 objects - it really doesn't like it - so I do these one at a time export and re-import then it sees them as one object - I am going to do a hint video on this issue next time mate - there might be a couple of things you weren't aware of that might help
As an Audi geek this is one of my favourite mechanical contrivances.
Beautiful and elegant model and great explanation thank you Robert - all your fans in County Cork Rep.Ireland
Glad you enjoyed it
This video provides the easiest explanation of torsion differential, a concept that is often difficult to grasp. Thanks allot Robert. ❤❤❤ Ur videos
Glad it was helpful!
The anti backdriving property is generally apparent with worm drives of greater than 5 to 1. 5:1 and less can be backdriven. Give or take dependent upon the coefficients of sliding friction between the worm and gear materials.
I was reading a Japanese research paper on it they talked a lot about contact angles
@ThinkingandTinkering
There are rappelling desending speed limiters that are little more than 5:1 worm drives being backdriven with an air drag vane on the "input" shaft. Air drag provides the fast shaft speed limiting load.
@@Vibe77Guy Old wind up music boxes used exactly that as speed regulation.
Vibration plays a big part in what can and cannot be backdriven.
Older Peugeot cars had a worm drive diff. About 3 or 4 to 1. Every time you lift off the throttle it back drives the engine
Robert Thanks for the explanation. I once worked in US Army maintenance calibrating all the torque wrenches, multimeters etc. used by the repair crew on helicopters. One of the wrenches was used on the nut used to secure the rotor to the aircraft and was rated at 10,000 ft/lbs ( not sure what the metric equivalent is) of torque. We had one that could not be brought into spec so the boss let us look inside before it was sent to higher up the chain. The inside looked very much like what you demonstrated and I can only conclude that is how they obtained the power required for the torque. Thanks for the lesson.
Great subject Robert, I never would have believed that you could design such an intricate gear system in Tinkercad 👍
it's quite an impressive program to say it's free and easy to use
Wow that was fast. Last episode I mentioned the Torsen diff and you have it made this episode. Torsen built a drive system that used 2 stacked rear ends where the one side was chain driven and the other side was gear driven 1:1. this allowed the lower rear end to be driven conventionally and conventional output to the wheels. The upper differential would perfectly differentiate and the ring gear would not move (input shaft not move). Then by driving the upper shaft left or right it would pass the change on to the lower drive. This was an idea to be used in tanks or other tracked vehicles to turn perfectly, at any speed, with out double transmissions or double engines that are conventional. Popular Mechanics back in High school Oh.... 40 yrs ago I'd say
I did it because you asked mate - and i liked it of course!
@@ThinkingandTinkering Thanks you are awesome!
Robert good to see you doing well. I've learned so much from you. Shout out to all my neighbors in Texas. Stay safe y'all.
thank you mate and cheers
@@ThinkingandTinkering thank you brother. ⭐
My car has a Torsen differential and so I've always been a bit fascinated by how they work. I will definitely be printing your model soon, thanks for the great content as usual 👍
Thanks Rob - I always thought these things are amazing but had no walk-through until now. Awesome job.
cheers mate
Our old Tractor had Torsen Differentials so it had kind of automatic Differential Locks. Really cool technic.
Excellent and informative as always!
Glad you enjoyed it!
Great Stuff Earthling
Blessings From Penzance, Kernow
cheers mate
An excellent mechanism. Thank you for making this video.
That’s so great thank you for doing this Robert! Your videos are excellent
I am just glad you like them!
What's interesting is that Torsen's patent hardly differs functionally or conceptually from Maurice Walter's patent of 1914 (US1164769A). Walter's 1958 filing (US2972265) is even closer. What's old is new again!
Maurice Walter's patents were used in his line of Walter trucks, perhaps most well known for his Sno Fighter plow trucks and airport crash trucks (fire trucks). His trucks were the eastern US answer to the midwestern FWD and subsequent Oshkosh trucks.
Maurice was a New York candy maker, turned candy equipment designer, turned motor vehicle designer. His early trucks were actually license built versions of the French four wheel drive Latil. Maurice's improvements of "100 % Traction" differentials, combined with a final gear reduction at the wheels, made for tough, "unstuckable" trucks.
Look here on YT of videos of Walter trucks plowing open roads through wind-packed 8 foot deep snow drifts on the Tug Hill Plateau in Upstate New York. Pretty amazing stuff.
I would love to get me a Sno Fighter...
it's the same old story all the time mate - the new just dressed up old lol
Now I want to see if I can adapt a few dead 5" grinder gearboxes to my ancient ride on mower which has a solid rear diff/shaft.
awesome - go for it
And put it on the tube.
Enjoyed very much, thanks Robert
Glad to hear it
Technically, a coarse enough worm gear can be driven, it does require a lot of torque to do so. Also technically a worm thread is a single tooth in a spiral.and the thing that stops a worm being driven is friction. Thus for the locking mechanism of this system is that it's easier for both output shafts to turn at the same speed when free running. It is an elegant solution though.
I thought so
Need LEGO colors and have everything snap together. Maybe some filament in colors? I still miss my Lego Technic set.
I sort of guessed that lol- cheers mate
My old GM truck has a "limited slip" differential. I'm not so sure about the name. It seems to be a diff that is limited because it slips on absolutely everything. The truck will get stuck on flat green grass in 4WD mode. I wonder how a Torsen diff would perform. 4WD is tricky because you have 1 power axle going to a transfer case (fancy diff) that powers 2 drive axles, each of which goes to an axle diff (pumpkin) that goes to 2 wheels. 4 wheels, 3 diffs, 2 drive axles, 1 power axle, and still going 0 m.p.h. :D
lol - i wonder too!
Remembering back to a Popular Mechanics back 40 yrs ago it said the 1 Torsion diff often was better than other types of diff's and was almost as good as 4WD. These diffs are used in airports on the tow vehicles used to tow the aircraft around. As long as one wheel has grip it will pull the plane
Back in the late 80's I had to trailer a 32' military boat ((I forget the weight) with a Gov't chevy Suburban. Every bump on the highway caused it to slip out of gear. I'd pull over, put it in park, put it back in 4wd and continue on to the next bump on the highway. Lather rinse repeat to infinity and beyond. Excruciatingly annoying trip at 50mph shuffling from Buffalo to Oswego NY. I chalked it up to the cheapo trend car manufacturers were resorting to in that era.
You forgot to try to hold one side of the differential while spinning the pinion shaft , both sides will lock. Another advantage is If the vehicle has one wheel on the air ,both wheel locks and the vehicle can still run.
cheers mate
So in essence it’s a limited slip differential, great description
pretty much mate and cheers
Thanks allot ❤❤❤ ur videos
awesome - cheers mate
This seems like a mechanical logic gate. The one way functions as your resistor! Its the AND function of the gears. Imagine the entangled complexity of the patterns of electron motion as these entangled gears interact at 2500 iter/s!
This is the power of leveraging inverse threshold approximation across multiple interactions...SeNT eNTS.
I'm not clear on if end narrow spur gears are fixed in position on each end of the long helical gears! are they both free to rotate? Or is one fixed & the other free to rotate? So, the free one mates with fixed one? What is the power path/loading capability?
I am fairly sure that Audi patented the Rosen diff in there quattro models. Very strong, light and efficient
interesting - cheers mate
beautiful explanation ! please straighten picture across from patti thank you!😃
Can you show what happens when you hold the other drive axl?
Wonderful model and excellent explanation, were these used in the four wheel drive Jensen Interceptor or some other competition car?
I know Lexus, chevrolet and Audi all used them - but i am not sure of competition cars mate
Very good
Thanks
That's a really interesting mechanism Rob! If you're going to use it backwards for two inputs to one output, what effect does their differing speeds have on the output? Like would it equalise the two inputs (split the diff) or would the higher speed input side determine the output?
because of the linking with the two spurs gears i think it would avergae it across the output - but to be honest I amnot too sure mate
Gleesman Torsen did a like mechanism you are talking about but used ordinary diffferentials.
Thanks 👍💪✌
You bet!
Another great clear demonstration of brain-ache mechanics!
Quick question... How do you stop Tinker cad grinding to a halt with such complicated designs? I often wait ages for their servers to catch up.
I try not to exceed 300 objects - it really doesn't like it - so I do these one at a time export and re-import then it sees them as one object - I am going to do a hint video on this issue next time mate - there might be a couple of things you weren't aware of that might help
@@ThinkingandTinkering Thank you! looking forward to it. I suspect there will be more than a couple of hints to learn :)
A worm gear can't be back driven except when your guitar slips out of tune . Don't try lubricating them either, that make it happen before your eyes.
cheers mate
Do you sell these working models?
Thumbs 👍
cheers mate
Ive only tried this once or twice BUT tinkercad also has an animation function....maybe that could be a cool visual for all of your hard work?
i wil check into it mate - cheers
I have a mini dynamo which gives 24 to 27 volts in output but the amperes are very less, how to increase the amperes😊😊
increase the input - check out the video what are the hell are amps - ruclips.net/video/Un_RhmS8OIc/видео.html
Muy bonito, pero sirve para algo ?
you dont repeat them three times only two times
😊
cheers mate
👍🏽
cheers mate
Huh?
I can't help if you don't ask a real question mate