Jump to content


Photo

Seamless Gearboxes


  • Please log in to reply
623 replies to this topic

#551 Tony Matthews

Tony Matthews
  • Member

  • 17,503 posts
  • Joined: September 08

Posted 16 March 2012 - 08:23

...if the shift event were truly instant with no loss of torque transfer, it would imply that the rotational speed of the output shaft would likewise instantly change to that of the selected gear.

This implies that there is an instant change in the speed of the driven wheels, and the car. There isn't, all that happens 'instantly' is a drop in engine revs.

Advertisement

#552 just me again

just me again
  • Member

  • 1,203 posts
  • Joined: August 00

Posted 16 March 2012 - 09:02

If we drive it with an electric motor, it will suffer the same problem as the original Tesla prototype.
That was fitted with a trick shift three speed gearbox, it lasted 2,000 miles.
Tesla now has a single speed and not out of choice.
The flat torque curve and the rigid torque path of a powerful ellectric motor simply destroys any conventional geartrain and shift mechanism.

Your description of the drive dog over run with no modulation or torque reduction is correct for a 'sledge hammer' shift using the described mechanism.
The gearbox will not last long doing it and neither will your teeth.
There will still be a gap in torque transfer at the point of over lap.
The drive train after the higher gear engageing components will be 'hammered' on with a torque spike and then the drive train will rebound before constant torque applies. At the rebound there will be NO torque transfered from the input shift components to the output.
This will be almost impossible to read at the propshaft, even without a damper.
The most likely result without a damper and other torque control, would be a pile of shift mechanism parts in the bottom of the gearbox caseing.


If instead modulating the torque you put foam, like the headrest foam in formula one, on the dogs and teeth. Then i think you will have a seamless gearbox by yours definition. ( because the dog and teeth will not bounce ).

Bjørn

ps: Ofcourse only theoretical. In practise it would be near impossible to Foam the dogs and teeth.

Edited by just me again, 16 March 2012 - 09:04.


#553 hogits2

hogits2
  • Member

  • 68 posts
  • Joined: March 10

Posted 16 March 2012 - 09:51

Presumably driveline oscillations, wind up, spikes etc. occur with any stepped ratio transmission as a result of changing ratios while under load.

Edited by hogits2, 16 March 2012 - 09:53.


#554 Catalina Park

Catalina Park
  • Member

  • 6,047 posts
  • Joined: July 01

Posted 16 March 2012 - 10:05

These aren't the droids you're looking for. This one can go on his way. <Waves hand>

I think this explains the problem in much more detail.


#555 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 16 March 2012 - 10:51

Here is a gearshift situation I would love to see the zeroshift graph for.
It is based on the transmission tests we used to undertake on new powertrains.
At that time this particular shift was undertaken during tests climbing the very steep hill in Porlock Devon.

Drive the vehicle up the steepest incline it is possible to find.
Get the engine revs to a level as high as possible but which still allows a gearshift down to the next lowest gear without a ratio change over rev.
This will result in the throttle at full throttle or very close to full throttle.
Change your zeroshift gearshift mechanism down to the next lowest gear.
Now show me the graph of the shift.

Oh I forgot to add.
If the shift doesnt take 10 minutes take a bucket for the bits.

Edited by 24gerrard, 16 March 2012 - 11:09.


#556 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 16 March 2012 - 10:57

If instead modulating the torque you put foam, like the headrest foam in formula one, on the dogs and teeth. Then i think you will have a seamless gearbox by yours definition. ( because the dog and teeth will not bounce ).

Bjørn

ps: Ofcourse only theoretical. In practise it would be near impossible to Foam the dogs and teeth.


Ha haha yes Bjorn by the way how is the car?

It is easier just to fill the gearbox with a thick oil.
Yet another reason why layshaft stepped boxes and trick mechaniisms to keep them going are well obsolete.

You could also design a radial damping spring inside the gear itself, that works well, maintains the gap at shift overlap at a faster shift speed and reduces jolt etc. I did that back in 1975 if I remember.

Edited by 24gerrard, 16 March 2012 - 11:16.


#557 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 16 March 2012 - 11:07

This implies that there is an instant change in the speed of the driven wheels, and the car. There isn't, all that happens 'instantly' is a drop in engine revs.


He was giving the theoretical result of an instant change in torque path with the engine supplying the torque.
He is well aware of the engines need to reduce in revs, which it also cannot do instantly.

#558 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 16 March 2012 - 11:18

I think this explains the problem in much more detail.


What is it with the Canadians obsession with kilts.
Weird.

#559 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 16 March 2012 - 14:42

So have I proved there is no such thing as a 'seamless' layshaft gearbox?
It seems the jury is still out. (no set time for deliberation here)
Surely there must be experts out there capable of upping the technical level of debate.

Edited by 24gerrard, 16 March 2012 - 14:43.


Advertisement

#560 slucas

slucas
  • Member

  • 74 posts
  • Joined: April 05

Posted 16 March 2012 - 18:53

I don't think the jury's still out. I think they came to their conclusion a while ago.

#561 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 16 March 2012 - 21:18

I don't think the jury's still out. I think they came to their conclusion a while ago.


Hmmm, must have missed that.
Did they post any kind of technical proof?

#562 gruntguru

gruntguru
  • Member

  • 5,802 posts
  • Joined: January 09

Posted 16 March 2012 - 22:24

Hm.... So it seems that.... I have a Zeroshift gearbox on the bench, I'm turning the input shaft slowly with my hand, it goes completely through the 1st to 2nd change and the output shaft won't stop turning at any point.

Put it back in the car and you have to reduce the input load/inertia during the change for practical purposes, so that it doesn't break.

No gap on the bench, induced gap when driving. The input shaft could have continous light torqe applied during the shift but this is perceived as a gap in the output.

Is this view ok?

Nicely put except - there is no need for an induced "gap" when driving. The torque mitigation devices only need to clip the torque spike ie reduce torque to the same level available prior to the shift.

For comfort in a road car the torque is also tapered down to the level available after the shift.

In a race car, much of the spike may in fact be tolerated.

#563 gruntguru

gruntguru
  • Member

  • 5,802 posts
  • Joined: January 09

Posted 16 March 2012 - 22:33

Hmmm, must have missed that.
Did they post any kind of technical proof?

He is talking about this forum where the vote is something like 20 to 1. Unfortunately the verdict has to be "not guilty" on the grounds of insanity.

The best technical proof so far is a graph of a shift showing output torque never falling significantly below second gear torque, yet according to the "transmission expert" (who also believes an auto trans does not slip two gears simultaneously during the handover from one to the other) there is a "gap".

#564 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 17 March 2012 - 09:39

He is talking about this forum where the vote is something like 20 to 1. Unfortunately the verdict has to be "not guilty" on the grounds of insanity.

The best technical proof so far is a graph of a shift showing output torque never falling significantly below second gear torque, yet according to the "transmission expert" (who also believes an auto trans does not slip two gears simultaneously during the handover from one to the other) there is a "gap".


The graph shows propshaft torque.
I have asked for a graph or data on the torque during shift over lap from the shift mechanism at input and output, where is it?

Automatic gearboxes do not slip 'gears' they slip friction surfaces on other geartrain components.
There can be a situation with no torque gap at a particular 'gear', because that gear is being used for the transfer of torque for both gear ratios either side of the shift over lap in question. The SAME gear 'set' is used in both gear ratios, it is other components that perform the shift over lap, where there IS a gap.

#565 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 17 March 2012 - 09:43

Nicely put except - there is no need for an induced "gap" when driving. The torque mitigation devices only need to clip the torque spike ie reduce torque to the same level available prior to the shift.

For comfort in a road car the torque is also tapered down to the level available after the shift.

In a race car, much of the spike may in fact be tolerated.


You realy do want to smash these gearboxes dont you grunt.
There is a gap in the transfer of torque between the input and output components in the shift mechanism at the point of shift over lap.
You cannot have an INSTANT change in the torque path, no ifs no buts and no may be.

#566 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 17 March 2012 - 09:54

He is talking about this forum where the vote is something like 20 to 1. Unfortunately the verdict has to be "not guilty" on the grounds of insanity.



I thought it was more because the majority remain unsure.

It proves a great deal about present day attitudes about truth and facts.
IMO these two king pins of human development are now well and truely subservient to the whims and resources of marketing and shallow values.
IMO we will see the results of this in F1 over the next few years as the real criminals take over.
If its plastered all over the media and song and danced about, it has to be true right??????????????

#567 carlt

carlt
  • Member

  • 1,261 posts
  • Joined: June 09

Posted 17 March 2012 - 10:28



IMO we will see the results of this in F1 over the next few years as the real criminals take over.


The criminals have been in charge since the 70's

It doesn't get much worse than capitalist sociopaths in bed with the tobacco companies promoting slow death

#568 Spoofski

Spoofski
  • Member

  • 262 posts
  • Joined: April 10

Posted 17 March 2012 - 10:45

In a race car, much of the spike may in fact be tolerated.

True. Pre-SECU there were vehicle state models of varying complexity used to decide the magnitude of tolerable torque spike. Now I believe there is a lateral g argument. By such means the shifts can be as racey or soft as is needed.

One of the big advantages of seamless boxes is the ability to shift whilst the car is heavily loaded without disturbing it. I would imagine this advantage is even greater on a Moto GP bike.

Whatever anyone's definition of seamless the fact is these things deliver torque to the wheels in as uninterrupted a flow as is necessary, even when the car is on the edge of grip and can't tolerate any 'seam'.

#569 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 17 March 2012 - 11:29

True. Pre-SECU there were vehicle state models of varying complexity used to decide the magnitude of tolerable torque spike. Now I believe there is a lateral g argument. By such means the shifts can be as racey or soft as is needed.

One of the big advantages of seamless boxes is the ability to shift whilst the car is heavily loaded without disturbing it. I would imagine this advantage is even greater on a Moto GP bike.

Whatever anyone's definition of seamless the fact is these things deliver torque to the wheels in as uninterrupted a flow as is necessary, even when the car is on the edge of grip and can't tolerate any 'seam'.


I agree they deliver torque to the rear wheels smoothly.
It is at the expense of either shift speed, efficiency or longevity.

There are better ways to do it.

Edited by 24gerrard, 17 March 2012 - 11:30.


#570 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 17 March 2012 - 11:33

The criminals have been in charge since the 70's

It doesn't get much worse than capitalist sociopaths in bed with the tobacco companies promoting slow death


Dont let it bother you, they are at the rear of the grid in Melbourne.

#571 carlt

carlt
  • Member

  • 1,261 posts
  • Joined: June 09

Posted 17 March 2012 - 12:53

Dont let it bother you, they are at the rear of the grid in Melbourne.

why should it bother me
i am interested in club motorsport
i don't follow f1

ps - they can't All be at the back of the grid

Edited by carlt, 17 March 2012 - 13:24.


#572 carlt

carlt
  • Member

  • 1,261 posts
  • Joined: June 09

Posted 17 March 2012 - 19:37

No need to go into the engineering of this discussion, Grunt especially has given extremely detailed explanations. Those who are still unsure I would ask to go through this thread from the beginning....it will not take you very many pages to understand.

MY CLAIM
I have designed, developed and driven such transmissions.

MY REQUEST
24gerrard, Autogyro, Keith or whatever else you want to call yourself.

Provide a single....and I mean a single shred of your OWN evidence to back up your claims that the shift event described is not possible in your next post.......and I mean in your very next post and I offer the following.

MY OFFER
I will personally pick you up and spend the day proving you wrong.

If by the end of that day you prove me wrong I will secure the investment to get your transmission prototyped and tested.

Up to you now gerrard....make it a good reply.



Have you 'put his money where your mouth is' yet

#573 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 17 March 2012 - 21:26

Have you 'put his money where your mouth is' yet


How?

The shift shown in the graph IS possible.
I am not saying that it is not possible, which he alludes to.
I am saying that the shift shown on the graph does not show the torque flow for the input and output components of the shift mechanism.
I am asking for an accurate graph showing the detail at this point, preferably for a full range of shifts needed for a useable vehicle.

I am not saying the shift mechanism cannot work in the way shown in the video.
I am saying that the video only shows the basic operation with light load.
Nothing shown, sufficiently explains the need for the torque control and modulation of the shift that is essential for real world operation of this mechanism.

His offer is a smoke screen to cover up the fact that he came onto the thread in an attempt to discredit my statements without any intention to back his post up with any technical explanation whatsoever.
He simply re-enforced my accusation that marketing hype and BS rule these days.
He offered to fund development of my system, why? Simply as a carrot to divert attention away from the issue of the GAP.
My ESERU can stand by itself for funding on its own merit, not as a prize in a marketing promotion, pushed by someone with vested interest in obsolete technology.
You see I realy do not have any interest in joining the old boys network.

#574 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 18 March 2012 - 08:30

Posted Image

output shaft rpm 1100rpm start of graph, 1125rpm (start of shift bracket, not overlap) 1125rpm at end of shift bracket, 1200rpm end of graph.
output shaft rpm 1000rpm at shift overlap. WHY THE DROP

NO TORQUE READINGS FOR THE INPUT AND OUTPUT SHIFT COMPONENTS


Your shout Sam.

PLAY IT AGAIN SAM.

Edited by 24gerrard, 18 March 2012 - 20:12.


#575 carlt

carlt
  • Member

  • 1,261 posts
  • Joined: June 09

Posted 18 March 2012 - 10:44

How?


My ESERU can stand by itself for funding on its own merit, not as a prize in a marketing promotion,



Thats probably why it is still languishing in your shed ?

#576 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 18 March 2012 - 11:47

Thats probably why it is still languishing in your shed ?


Could be, perhaps we will never know.

#577 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 18 March 2012 - 19:09

Did you see Button change up from 1st to 2nd gear too early off the start line at Melbourne.
The shift nearly broke his neck.
At least the shift mechanism lasted for the race.
Some did not.
A bit crude for the 21st Century though.

#578 SamSeles

SamSeles
  • New Member

  • 8 posts
  • Joined: February 12

Posted 18 March 2012 - 20:16

I am not saying the shift mechanism cannot work in the way shown in the video


The shift shown in the graph IS possible.


:clap:

#579 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 18 March 2012 - 20:21

:clap:


:rotfl: :lol:

You know exactly what I mean Sam.

Advertisement

#580 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 19 March 2012 - 09:29

The shift shown in the graph IS possible.
I am not saying that it is not possible, which he alludes to.
I am saying that the shift shown on the graph does not show the torque flow for the input and output components of the shift mechanism.
I am asking for an accurate graph showing the detail at this point, preferably for a full range of shifts needed for a useable vehicle.

I am not saying the shift mechanism cannot work in the way shown in the video.
I am saying that the video only shows the basic operation with light load.
Nothing shown, sufficiently explains the need for the torque control and modulation of the shift that is essential for real world operation of this mechanism.

Ask Jenson Button if such a 'seamless' shift is acceptable without reducing the torque from the engine and or declutching or absorbing the shock.
Shift mechanism's like the zeroshift achieve a smooth shift as felt at the road wheels through compromise.
Of course the F1 shifts will appear faster, the shift mechanism has to deal with far less inertia from the crankshaft and a far lighter car.

What you hear when the cars 'shift' is the engagement of the next gear selected, you do not hear the torque reduction or the declutch.
Show me torque graphs for the input and output shift components at the shift over lap.



#581 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 20 March 2012 - 09:15

15 pages

AND NOT ONE TECHNICAL EXPLANATION ON HOW IT CAN BE POSSIBLE TO TRANSFER TORQUE 'INSTANTLY' FROM ONE GEAR RATIO TO ANOTHER IN A STEPPED LAYSHAFT GEARBOX.


NOT ONE

:mad: :mad:

#582 Fondles

Fondles
  • Member

  • 50 posts
  • Joined: July 11

Posted 20 March 2012 - 13:03

15 pages

AND NOT ONE TECHNICAL EXPLANATION ON HOW IT CAN BE POSSIBLE TO TRANSFER TORQUE 'INSTANTLY' FROM ONE GEAR RATIO TO ANOTHER IN A STEPPED LAYSHAFT GEARBOX.


NOT ONE

:mad: :mad:


There has been many in fact. You have chosen to ignore them unfortunately.

#583 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 20 March 2012 - 13:05

There has been many in fact. You have chosen to ignore them unfortunately.


If there are many please select just one and quote it.

#584 Fondles

Fondles
  • Member

  • 50 posts
  • Joined: July 11

Posted 20 March 2012 - 13:20

If there are many please select just one and quote it.


So you can ignore it again?
No.

The Zeroshift mechanism seems pretty straightforward to me, and also the reason for reducing the engine torque for the shift.
It's quite easy to understand how it does a completely gapless shift.
I am not interested and do not participate in extended arguments so that is all I am going to say on the subject.

#585 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 20 March 2012 - 14:07

So you can ignore it again?
No.

The Zeroshift mechanism seems pretty straightforward to me, and also the reason for reducing the engine torque for the shift.
It's quite easy to understand how it does a completely gapless shift.
I am not interested and do not participate in extended arguments so that is all I am going to say on the subject.


So you dont know.

The zeroshift mechanism will work as shown and described. no problem I fully agree.

The graph is also accurate for the shift shown using the mechanism. no problem I fully agree.

If the mechanism is used with engine 'power' on and with no outside torque control (as in the video) the result will be a huge jolt or bang.
It will be luck as to whether the components survive the shift.
The sudden application of engine torque through the new high gear will wind up the drive train after the shift mechanism, which will spring back giving a gap in torque transfer at the shift mechanism

If engine torque is reduced and the clutch disengaged at the shift to reduce this 'BANG', (as on the graph) this will take the input torque off the 1st gear bullets driving in 1st gear.
The result will be that the first gear will disengage before second gear engages, there will be a gap in torque transfer and no bang because of the reduced torque input.

Look at the graph, the engine torque is reduced and the clutch does disengage.
Look at the zeroshift video to see the sequence of selector fork movements to confirm the timing needed for this to occur.

Non of this outside torque control is needed with a racing dog box, the drivers skill achieves a FULL power on shift with NO clutch disengagement.

Therefore the dog box is far more efficient with manual shifting and by comparison the zeroshift is far smoother at the wheels.

IMO a seamless F1 box looses around a second a lap in lost torque transfer over a manual dog box.
Of course today it is almost impossible for a driver to use a dog box effectively, the downforce levels prevent such use.

Edited by 24gerrard, 20 March 2012 - 14:14.


#586 Woody3says

Woody3says
  • Member

  • 426 posts
  • Joined: January 11

Posted 20 March 2012 - 16:27

Ok, Ill bite. I am no expert in boxes that shift, all mine stay in one ratio....

BUT:

How on earth can you say that a manual dog will shift FASTER than the current "seamless" box??? Shifts of 40 mil sec VS the human hand physically pulling the shift level from one gear to another? There is a reason why you redlight in drag racing when even though the time is not faster than zero sec........human reaction time CAN NOT be quicker than the electronic selection of a F1 box.

Remember, I can play nice.....your turn!

#587 Spoofski

Spoofski
  • Member

  • 262 posts
  • Joined: April 10

Posted 20 March 2012 - 17:22

Of course today it is almost impossible for a driver to use a dog box effectively, the downforce levels prevent such use.

Compared to the ground-effect era......?

#588 REN_AF1

REN_AF1
  • Member

  • 75 posts
  • Joined: October 08

Posted 20 March 2012 - 17:52

Ok, Ill bite. I am no expert in boxes that shift, all mine stay in one ratio....

BUT:

How on earth can you say that a manual dog will shift FASTER than the current "seamless" box??? Shifts of 40 mil sec VS the human hand physically pulling the shift level from one gear to another? There is a reason why you redlight in drag racing when even though the time is not faster than zero sec........human reaction time CAN NOT be quicker than the electronic selection of a F1 box.

Remember, I can play nice.....your turn!


Perhaps it is not what he says, as much as what YOU read.. I did not see 24gerrard state the actual sliding action of cogs and dogs in the Zeroshift to be slower than a manual shift.
What he said is; that the modulation of throttle and clutch, needed for the Zeroshift AMT to work without destroying itself, dumbs down power transfer to where a conventional dogbox might be a better option.

R (not vouching for said claim, merely pointing it out)



#589 rachael

rachael
  • Member

  • 111 posts
  • Joined: October 10

Posted 20 March 2012 - 19:20

IMO a seamless F1 box looses around a second a lap in lost torque transfer over a manual dog box.
Of course today it is almost impossible for a driver to use a dog box effectively, the downforce levels prevent such use.

Phhaarrttt... Oh dear grandpa has been at the Guinness and oysters again, whose turn is it to take him to the bathroom?

#590 SamSeles

SamSeles
  • New Member

  • 8 posts
  • Joined: February 12

Posted 20 March 2012 - 20:10

It's a crying shame when such a valuable source of knowledge as this technical forum is destroyed by certain individuals.

I have enjoyed reading many discussions over the years and have promoted the use of such forums as a source of knowledge to our young engineering apprentices.
This particular thread has become more a source of amusement for them recently.

Unfortunately I see no reason to post any further replies on this subject.

:wave:




#591 Woody3says

Woody3says
  • Member

  • 426 posts
  • Joined: January 11

Posted 20 March 2012 - 20:56

Perhaps it is not what he says, as much as what YOU read.. I did not see 24gerrard state the actual sliding action of cogs and dogs in the Zeroshift to be slower than a manual shift.
What he said is; that the modulation of throttle and clutch, needed for the Zeroshift AMT to work without destroying itself, dumbs down power transfer to where a conventional dogbox might be a better option.

R (not vouching for said claim, merely pointing it out)


IMO a seamless F1 box looses around a second a lap in lost torque transfer over a manual dog box.


My reply is specific to this part, not so much towards the zero shift. If the old, antiquated F1-style box is worse in 24s mind than the zero shift, he seems to imply that a full on manual dog box is therefore more efficient than the current boxes are. I ask for clarification.....

If I remember right there is nothing in the current rules that abolish a good ol fashion manual box. We're it more efficient they would run those instead of the hugely expensive current boxes.....correct?

#592 NTSOS

NTSOS
  • Member

  • 692 posts
  • Joined: February 05

Posted 20 March 2012 - 21:27

If engine torque is reduced and the clutch disengaged at the shift to reduce this 'BANG', (as on the graph) this will take the input torque off the 1st gear bullets driving in 1st gear.


Hmmm.....are you saying that the 1st gear drive bullets will lose contact with the 1st gear drive dogs as in backlash or overrun?

Just wondering!

John

#593 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 20 March 2012 - 22:50

It's a crying shame when such a valuable source of knowledge as this technical forum is destroyed by certain individuals.

I have enjoyed reading many discussions over the years and have promoted the use of such forums as a source of knowledge to our young engineering apprentices.
This particular thread has become more a source of amusement for them recently.

Unfortunately I see no reason to post any further replies on this subject.

:wave:


I agree Sam those who promote the so called 'seamless' shifting gearbox mechanisms have a lot to answer for.
It is just a shame they do not have an argument and have to run away from discussion.
I suppose with so much resting on their claims in the market place it is to be expected.

Do not accuse me of destroying any forum, just supply the torque figures I ask for to prove your case.
That is all it needs.

#594 gruntguru

gruntguru
  • Member

  • 5,802 posts
  • Joined: January 09

Posted 20 March 2012 - 23:17

I have said this before. The torque figures are there in front of your face. The input torque is equal to output torque divided by the gear ratio. The torque on the input side of a slipping clutch is equal to the torque on the output side. It is your inability to accept statements from qualified people who understand these things that everybody on this forum is complaining about.

#595 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 20 March 2012 - 23:18

Hmmm.....are you saying that the 1st gear drive bullets will lose contact with the 1st gear drive dogs as in backlash or overrun?

Just wondering!

John


Look carefuly at the video.



It is the 2nd gear selector that locks the first gear into its fully engaged position. NOT THE 1ST GEAR SELECTOR.
The same 2nd gear selector fork moves away from first gear and its locked position, BEFORE second gear is selected.
This action pre-loads the selector fork spring towards 1st gear disengagement.

The 2nd gear selector continues to pr-engage second gear. (both selectors show both gears pre-engaged NOT FULLY ENGAGED)
The first gear selector moves to fully engage second gear with a FIERCE BANG, which as shown over runs the pre-loaded 1st gear bullets allowing them to spring out to disengage 1st gear. Exactly as shown in the video but with power on and NO torque modulation. NOT UNDER NO LOAD AS IN THE VIDEO

If reduced input torque from the engine and the disengaged clutch is added, this is enough to reduce load on 1st gear so as to allow the Ist gear bullets to spring out of 1st gear engagement BEFORE the 2nd gear bullets are fully engaged by the first selector.
It is the 1st gear selector that FULLY engages 2nd gear. NOT THE 2ND GEAR SELECTOR.

For the whole time the 2nd gear selector fork is moving out of 1st lock and into 2nd pre-lock, the 1st gear bullets are being sprung loaded to disengage.
It is only the torque applied to 1st gear that keeps the 1st gear bullets engaged.
ANY REDUCTION IN TORQUE TO FIRST GEAR, WHETHER FROM A SLEDGE HAMMER BANG TO SECOND GEAR, OR A REDUCTION IN INPUT TORQUE BY ANY MEANS WILL DISENGAGE THE 1ST GEAR BULLETS AND 1ST GEAR.
There is a gap!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Certain people posting on this thread know this already.

Edited by 24gerrard, 20 March 2012 - 23:37.


#596 SamSeles

SamSeles
  • New Member

  • 8 posts
  • Joined: February 12

Posted 20 March 2012 - 23:43

AAAAaaarrrrrrrgggghhhhh.....just one more

Look carefuly at the video.


OK

It is the 2nd gear selector that locks the first gear into its fully engaged position. NOT THE 1ST GEAR SELECTOR.


WRONG! - 2nd gear selector fork provides overrun torque in first gear only... you do not understand how it works!

The same 2nd gear selector fork moves away from first gear and its locked position, BEFORE second gear is selected.


WRONG! - 2nd gear selector fork can move freely it is not locked... you do not understand how it works!

The 2nd gear selector continues to pr-engage second gear.


WRONG! - there is no pre-engagement...you do not understand how it works!

The first gear selector moves to fully engage second gear with a FIERCE BANG


WRONG! - First gear selector physically cannot engage second...you do not understand how it works!

Until you can get this basic functionality through your skull you have no chance of getting any further!!!!

You cannot see that everyone else it attempting to explain this can you?

Edited by SamSeles, 20 March 2012 - 23:48.


#597 gruntguru

gruntguru
  • Member

  • 5,802 posts
  • Joined: January 09

Posted 21 March 2012 - 00:00

15 pages

AND NOT ONE TECHNICAL EXPLANATION ON HOW IT CAN BE POSSIBLE TO TRANSFER TORQUE 'INSTANTLY' FROM ONE GEAR RATIO TO ANOTHER IN A STEPPED LAYSHAFT GEARBOX.


NOT ONE

:mad: :mad:

I wondered why you weren't getting it and this confirms it. YOU HAVEN'T BEEN READING OTHER PEOPLES POSTS! Here's a few you missed.

Post#s
45
79
103
133
180
234
235
238
243
246
248
256
259
428 (Page 11)
434
466
468 - very important! Understand the railcar analogy and tell me why you think it is wrong.

#598 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 21 March 2012 - 00:22

[quote]name='SamSeles' date='Mar 20 2012, 23:43' post='5609490']
AAAAaaarrrrrrrgggghhhhh.....just one more



OK



WRONG! - 2nd gear selector fork provides overrun torque in first gear only... you do not understand how it works![/quote]

Yes I do. If 1st is fully engaged with the 1st selector fork, then why do you need the second fork to move to hold engagement in over run?


[quote]WRONG! - 2nd gear selector fork can move freely it is not locked... you do not understand how it works!
[/quote]

Yes I do. I know the 2nd gear selector fork can move freely when moved by its selector.
Both can. They can also lock the other. You explain this is for over run, why is it needed if as you say one fork fully engages one gear?

[quote]WRONG! - there is no pre-engagement...you do not understand how it works![/quote]

Pre-engagement is perhaps the wrong term, it is engaged just not locked.

[quote]WRONG! - First gear selector physically cannot engage second...you do not understand how it works![/quote]

I know 1st gear selector cannot engage second (wrong term) it locks it in full engagement.
I was wrong here, it is the 2nd gear selector moving the 2nd gear bullets into engagement with second gear that caused the fierce bang.
It is not the 1st gear selector moving to lock the engaged second gear bullets.

Until you can get this basic functionality through your skull you have no chance of getting any further!!!!

[quote]You cannot see that everyone else it attempting to explain this can you?[/quote]

You have yet to convince me.

Edited by 24gerrard, 21 March 2012 - 00:33.


#599 24gerrard

24gerrard
  • Member

  • 2,008 posts
  • Joined: March 11

Posted 21 March 2012 - 00:48

I wondered why you weren't getting it and this confirms it. YOU HAVEN'T BEEN READING OTHER PEOPLES POSTS! Here's a few you missed.

Post#s
45
79
103
133
180
234
235
238
243
246
248
256
259
428 (Page 11)
434
466
468 - very important! Understand the railcar analogy and tell me why you think it is wrong.


It is NOT wrong.
The zeroshift mechanism will change from one gear to the next as smooth as the rail car analogy but ONLY when no torque is being transfered as in the video.
Add a source of input torque and an output drive train driven by the inertia of a moveing vehicle and without modulation and control of the forces, the engagement will be a fierce bang that will wind up the drive train, which will rebound cutting the torque to output at that instant.

Advertisement

#600 Slowinfastout

Slowinfastout
  • Member

  • 9,681 posts
  • Joined: October 07

Posted 21 March 2012 - 01:08

Posted Image