Zeroshift Transmission...
03-Mar-2004, 12:08 AM
#1
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Zeroshift Transmission...
Just read last month's issue of racecar engineering.
There was an article about this revolutionary transmission whereby you don't have to release the throttle while shifting.
Here's a link to the article:
http://www.pistonheadstv.com/images/...arEng_0204.pdf
I spent half a day at work trying to figure out how such a transmission would work...
Anyone got any ideas???
There was an article about this revolutionary transmission whereby you don't have to release the throttle while shifting.
Here's a link to the article:
http://www.pistonheadstv.com/images/...arEng_0204.pdf
I spent half a day at work trying to figure out how such a transmission would work...
Anyone got any ideas???
03-Mar-2004, 06:49 AM
#2
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i'm to lazy to check that link but for sequential gear boxes (where you dont need to release the throttle either), the throttle is fly by wire and the computer automatically lowers throttle to get it at the correct speed to shift gears....
although if you "need" to release the trottle to shift gears in normal cars.... its just not advised
although if you "need" to release the trottle to shift gears in normal cars.... its just not advised
03-Mar-2004, 10:53 AM
#6
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Originally posted by PunkInDrublic
i'm to lazy to check that link but for sequential gear boxes (where you dont need to release the throttle either), the throttle is fly by wire and the computer automatically lowers throttle to get it at the correct speed to shift gears....
although if you "need" to release the trottle to shift gears in normal cars.... its just not advised
i'm to lazy to check that link but for sequential gear boxes (where you dont need to release the throttle either), the throttle is fly by wire and the computer automatically lowers throttle to get it at the correct speed to shift gears....
although if you "need" to release the trottle to shift gears in normal cars.... its just not advised
03-Mar-2004, 06:59 PM
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Originally posted by bbarbulo
Hondata allows full throttle shifting too
Hondata allows full throttle shifting too
but you're missing the point of this "new and revolutionary" gearbox.
They claim that when you shift, there is no disengagement of engine from the wheels. There is no clutch to disengage except when you want to completely stop the car.
I'm guessing they've figured out some sort of novel dog gear that will engage smoothly under load.
04-Mar-2004, 12:39 AM
#9
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it's just the design of the gears the teeth fit way more easily into place.... the gears we have are Helical gears and therefore need something (synchros) to line everything up correctly....
now I know your asking well WTF??? why don't these magical gears always get used.... to answer that do this ... put the car in first and drive right to the red line.... listen for noise.... then do the same in reverse.... you hear the reverse "whine" alot more thats because they used dog engagement gears for reverse... that "whining" is the gears ... now image spinning that to higher speeds... in a race car noise doesn't mater in a street car noise is everything and thats why they arn't used ...
now I know your asking well WTF??? why don't these magical gears always get used.... to answer that do this ... put the car in first and drive right to the red line.... listen for noise.... then do the same in reverse.... you hear the reverse "whine" alot more thats because they used dog engagement gears for reverse... that "whining" is the gears ... now image spinning that to higher speeds... in a race car noise doesn't mater in a street car noise is everything and thats why they arn't used ...
04-Mar-2004, 01:29 AM
#10
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old school honda civics used that CVT continuiously variable transmition... i dont know hte mechanics of it but it was pulleys or something... only good for super weak engines... like in old civics...
recently i think it was audi... they took that technology and applied it to a much more powerful car... so essentially the gear ratios could phase to any ration within the upper and lower limits... they had another option for these trannies that allowed for normal shifting through 6 "preset" ratios... now for that tranny to "shift" no clutch work was needed nor did the engine ever dissconnect from the tranny...
maybe that is what your hearing about?
recently i think it was audi... they took that technology and applied it to a much more powerful car... so essentially the gear ratios could phase to any ration within the upper and lower limits... they had another option for these trannies that allowed for normal shifting through 6 "preset" ratios... now for that tranny to "shift" no clutch work was needed nor did the engine ever dissconnect from the tranny...
maybe that is what your hearing about?
04-Mar-2004, 05:16 PM
#11
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Nope, this gearbox is definitely not a CVT.
In their diagram, they saw that the system can be retrofittable into a conventional manual gearbox.
check out the pdf... nobody seems to be reading it carefully!
In their diagram, they saw that the system can be retrofittable into a conventional manual gearbox.
check out the pdf... nobody seems to be reading it carefully!
Originally posted by PunkInDrublic
old school honda civics used that CVT continuiously variable transmition... i dont know hte mechanics of it but it was pulleys or something... only good for super weak engines... like in old civics...
recently i think it was audi... they took that technology and applied it to a much more powerful car... so essentially the gear ratios could phase to any ration within the upper and lower limits... they had another option for these trannies that allowed for normal shifting through 6 "preset" ratios... now for that tranny to "shift" no clutch work was needed nor did the engine ever dissconnect from the tranny...
maybe that is what your hearing about?
old school honda civics used that CVT continuiously variable transmition... i dont know hte mechanics of it but it was pulleys or something... only good for super weak engines... like in old civics...
recently i think it was audi... they took that technology and applied it to a much more powerful car... so essentially the gear ratios could phase to any ration within the upper and lower limits... they had another option for these trannies that allowed for normal shifting through 6 "preset" ratios... now for that tranny to "shift" no clutch work was needed nor did the engine ever dissconnect from the tranny...
maybe that is what your hearing about?
04-Mar-2004, 05:19 PM
#12
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Yes, I understand what you're saying...
but shift without synchros is only possible if you unload the input shaft and rev match the transmission.
It seems in this gearbox, you don't have to rev match nor unload the input shaft.
He makes an anology to a rear bicycle derailler... a quasi smooth transition from one gear to another that is possible underload...
Following me?
but shift without synchros is only possible if you unload the input shaft and rev match the transmission.
It seems in this gearbox, you don't have to rev match nor unload the input shaft.
He makes an anology to a rear bicycle derailler... a quasi smooth transition from one gear to another that is possible underload...
Following me?
Originally posted by gatherer
it's just the design of the gears the teeth fit way more easily into place.... the gears we have are Helical gears and therefore need something (synchros) to line everything up correctly....
now I know your asking well WTF??? why don't these magical gears always get used.... to answer that do this ... put the car in first and drive right to the red line.... listen for noise.... then do the same in reverse.... you hear the reverse "whine" alot more thats because they used dog engagement gears for reverse... that "whining" is the gears ... now image spinning that to higher speeds... in a race car noise doesn't mater in a street car noise is everything and thats why they arn't used ...
it's just the design of the gears the teeth fit way more easily into place.... the gears we have are Helical gears and therefore need something (synchros) to line everything up correctly....
now I know your asking well WTF??? why don't these magical gears always get used.... to answer that do this ... put the car in first and drive right to the red line.... listen for noise.... then do the same in reverse.... you hear the reverse "whine" alot more thats because they used dog engagement gears for reverse... that "whining" is the gears ... now image spinning that to higher speeds... in a race car noise doesn't mater in a street car noise is everything and thats why they arn't used ...
04-Mar-2004, 10:30 PM
#13
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what your not understanding is that you have to unload the input shaft only with the standard gears in a hojnda transmission
with the straight cut dog leg engagement gears you don't need to unload the input shaft....
with the straight cut dog leg engagement gears you don't need to unload the input shaft....
04-Mar-2004, 11:16 PM
#14
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Yes... I knew that... but I also stated that the new gearbox doesn't require rev matching... With straight cut gears, you have to rev match to shift without using the clutch... and even then, I believe you have to let off the gas momentarily to blip the throttle...
Originally posted by gatherer
what your not understanding is that you have to unload the input shaft only with the standard gears in a hojnda transmission
with the straight cut dog leg engagement gears you don't need to unload the input shaft....
what your not understanding is that you have to unload the input shaft only with the standard gears in a hojnda transmission
with the straight cut dog leg engagement gears you don't need to unload the input shaft....
05-Mar-2004, 07:28 AM
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ok yes with just straight cut gears ...... but we are speaking about Straight cut gears with a dog leg engeagement system .... (creating straight cut dog leg engagement gears..) the result is something that doesn't require rev matching and doesn't where out (like synchros do if you don't use the clutch 
) so the dog leg engagement part works like a synchro but without the need to disengage the engine.....
) so the dog leg engagement part works like a synchro but without the need to disengage the engine.....
05-Mar-2004, 08:18 AM
#17
Originally posted by TauMax
check out the pdf... nobody seems to be reading it carefully!
check out the pdf... nobody seems to be reading it carefully!
) and I didn't look at it then either. It would be as pointless as me looking at Ferrari brochures. Ppl like me don't own Ferraris. Or like reading Car&Driver when I'm not even shopping for a car. 
You seem pretty invested in the idea... do you perhaps have the estimated $30-50K USD for this kinda tranny?
05-Mar-2004, 09:10 AM
#18
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Originally posted by gatherer
ok yes with just straight cut gears ...... but we are speaking about Straight cut gears with a dog leg engeagement system .... (creating straight cut dog leg engagement gears..) the result is something that doesn't require rev matching and doesn't where out (like synchros do if you don't use the clutch) so the dog leg engagement part works like a synchro but without the need to disengage the engine.....
ok yes with just straight cut gears ...... but we are speaking about Straight cut gears with a dog leg engeagement system .... (creating straight cut dog leg engagement gears..) the result is something that doesn't require rev matching and doesn't where out (like synchros do if you don't use the clutch
) so the dog leg engagement part works like a synchro but without the need to disengage the engine.....
05-Mar-2004, 10:27 PM
#19
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LOL...
I have no affiliation with these guys!
I am merely sharing this with ppl on this board so that we may brainstorm on how they've actually accomplished what they did.
Like I said before, I spent half a day at work trying to figure out the exact mechanisms that were used.
I'm never going to own a Ferrari either, but that doesn't mean I can't try and figure out any new technology that they may implement.
Bottom line is that I'm interested at this tranny from an engineering standpoint... not as an consumer.
I have no affiliation with these guys!
I am merely sharing this with ppl on this board so that we may brainstorm on how they've actually accomplished what they did.
Like I said before, I spent half a day at work trying to figure out the exact mechanisms that were used.
I'm never going to own a Ferrari either, but that doesn't mean I can't try and figure out any new technology that they may implement.
Bottom line is that I'm interested at this tranny from an engineering standpoint... not as an consumer.
Originally posted by bbarbulo
Or at all in my case. I don't give a crap, I'm never going to own a cluchless tranny so why worry about it. My buddy sent me this article months ago (well, 4-6 weeks ) and I didn't look at it then either. It would be as pointless as me looking at Ferrari brochures. Ppl like me don't own Ferraris. Or like reading Car&Driver when I'm not even shopping for a car.
You seem pretty invested in the idea... do you perhaps have the estimated $30-50K USD for this kinda tranny?
Or at all in my case. I don't give a crap, I'm never going to own a cluchless tranny so why worry about it. My buddy sent me this article months ago (well, 4-6 weeks
) and I didn't look at it then either. It would be as pointless as me looking at Ferrari brochures. Ppl like me don't own Ferraris. Or like reading Car&Driver when I'm not even shopping for a car. You seem pretty invested in the idea... do you perhaps have the estimated $30-50K USD for this kinda tranny?
05-Mar-2004, 10:30 PM
#20
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Can you post me a link that states that you can shift under load with straight cut dog leg gears?
I'm still not convinced that you can get away without using a clutch.
Why is it that for street cars, this gear type isn't recommended?
I'm still not convinced that you can get away without using a clutch.
Why is it that for street cars, this gear type isn't recommended?
Originally posted by gatherer
ok yes with just straight cut gears ...... but we are speaking about Straight cut gears with a dog leg engeagement system .... (creating straight cut dog leg engagement gears..) the result is something that doesn't require rev matching and doesn't where out (like synchros do if you don't use the clutch) so the dog leg engagement part works like a synchro but without the need to disengage the engine.....
ok yes with just straight cut gears ...... but we are speaking about Straight cut gears with a dog leg engeagement system .... (creating straight cut dog leg engagement gears..) the result is something that doesn't require rev matching and doesn't where out (like synchros do if you don't use the clutch
) so the dog leg engagement part works like a synchro but without the need to disengage the engine.....
