Manual CVT? 2

[808state]

Notes: not Seismonic or Triptronic.
-I have the idea going through a patent at the time.
I would like some feed back and possible suggested CVT's that can go through a modification that allows the driver to adjust the ratio of a cvt "manually". I designed a center console with a "Slider" airplane throttle-like shifter that will have P, R, N, and Drive being a large area to move, shift, slide, up and down. The shifter's location on the console, will be connected mechanichally (linkage) or electronically (hardware) to the Ratio control of a cvt.
I have superiors that would help me out with the modification of a car and a tranny that seems affordable.
But what models to choose from? Should I sell the idea off to a manufacture? Or folow it through myself?
Any questions to this idea please post for feedback.

Hoorah Grease Monkey

 

[808state]

Other feed back so far. Note: long (unprofesional)thread with few members.

http://www.car-forums.com/talk/showthread.php?t=9175

Hoorah Grease Monkey

 

[patprimmer]

Why?

Isn't the main advantage of a CTV the fact that it can always be in the optimum gear for either performance or economy.

I am sure that a properly programed computer control will do either much more accurately than a driver.

Where will you find a car buyer that wants to constantly monitor a manifold vacuum gauge and tachometer and make constant adjustments. When will he have time to navigate and attend to other controls and driver duties like watching the road, avoiding accidents etc.

Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[808state]

http://www.personal.psu.edu/users/w/f/wfw105/Cx Report 2.htm

A CVT can be less expensive to construct than an automatic, more versatile than a manual, and can span gear ratios larger than traditional manuals. The control system is a major part of the CVT’s success. CVTs can be controlled manually, where the additional force placed on a pulley or belt causes the belt to ride on a higher or lower rim on the pulley. They can also be controlled centrifugally, with only one degree of feedback. In this case a governor device is applied to react to the rotation speed of the shaft going through the pulley. With increased speed the governor applies more force to the system initiating a shift up or down. Most modern vehicles use an electronically controlled CVT design or eCVT. In this design, an electric motor drives the motion that allows shifting. This electric motor is given feedback from various sources that sense torque, engine speed, load, etc. The challenge in creating a CVT that operates close to theoretical perfection is in designing the operating system. Japanese manufacturers have much experience installing these into small-displacement cars, and as many as 40 different models exist that have not been exposed to the U.S. market. Now the market is coming to the U.S. and the same manufacturers are pushing to develop CVTs that can be fitted on larger displacement vehicles. It has been anticipated that in 2005 and 2006 the U.S. will see increased interest in the CVT for its simplicity and versatility. Technology is paving the way for a better CVT and the growth of this design is quite promising.



Hoorah Grease Monkey

 

[crysta1c1ear]

http://www.histomobile.com/histomob/internet/techniqu/83.jpg

Step back to 1906 - 1920?

 

[patprimmer]

That's why to use CVT, but why make it manual control.

Manual control will lose most of the advantages as almost all drivers will never maintain anywhere near optimum.

A Dutch car called a DAF, later owned by Volvo also had a CTV. I am not sure of the history, but I think it was about the late 60's through to the 80's. It used a belt and opposing cones I think.

I think it was controlled by engine speed and throttle position.

I would think the modern way would be an ECU, with careful mapping according to manifold pressure and engine speed to control a linear motor, that controlled belt position if that is the style you have in mind.


Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[808state]

Please read what others have written on the other forum and youll understand that the tranny will keep the automatic ratio control ie(ECU), as an option. Why not make it both? The mini has preprogrammed gears and the option of auto. The mini also has a friction plate type clutch (similar to 5 man.)
I want (that is), I will make a CVT with the option to control the ratio myself and the option of auto (saving gas, more efficeint power usage ect.
On top of all this a clutch is to be added. I dont expect most to agree. You cant drive with one hand? Do you hate the commute through traffic in a manual? Well some drivers dont mind. and some want more control of the car, because although the CVT's ECU is advacing through technology, the human brain can influence change to the way machinary works to suite the situation, before the situation occurs. All that im asking is some help to find a CVT to modify and car to modify. The patent is already underway.

Hoorah Grease Monkey

 

[patprimmer]

808state

Your last post is quite a different story to your first post, and certainly clarifies the situation.

Can you adapt a manually operated electronic controller to override the automatic controller, like a slider operating a variable resistor to add a higher priority signal source.

Sorry if my terminology is wrong, but electronics and controllers is not my strongest area.

Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[NormPeterson]

If what you're getting at is a method of getting the transmission to work in harmony with the driver's wishes at any given instant, I think I follow (and pretty much agree). Nobody's automatic tranny programming or learning is ever going to be able to consistently predict what my expectations of it might be (hell, even I don't always know much in advance either). And believe me, when I'm forced to drive a slush-box equipped vehicle I do notice automatic upshifts that either occur when I would not make a manual shift (even with identical gearing) or don't occur where I would. The corresponding CVT behavior might be brief periods of excessive revving or sluggishness relative to your intentions.

Anyway, it seems to me that you want a controller to which you have a single input that causes it to work at what I'd describe as a certain level of intensity while in the forward range only. You have to keep it very simple. Don't overestimate the buyer whose credentials consist of a positive pulse and apparent financial means, as poor market results can arise from precisely that kind of source. It's probably best to keep all the control functions in one place. Perhaps a lever to shift between P, R, N, and D, with the variable resistance mechanism that controls an input signal voltage to the controller located in the shift knob.

It's probably unnecessary for this to be infinitely variable, as it isn't affecting discrete shift points. So a step-wise resistance (like the radio volume control on my 2001 Maxima) might be a reasonable approach. Just how many steps should involve some marketing research. This still feels closer to an automatic tranny than to a traditional manual, so you need data from people whose attitudes toward current automatics aren't as hard-core as mine.

BTW, isn't CVT standard fitment on Nissan's Murano and available on Ford's new Five Hundred? 3 liters and up.

Norm

 

[808state]

Nice feed back and suggestions Peterson.
The patent does include the shifter which I thought must have to be a system including a vaiable resistor (like that of a car on an electric track or even a volume control knob) but the point is to have three desired ways to drive or operate the vehicle:
1. Automatic, Using the CVT hardware to it its thing,(save gas and ease of use ect.)
2. Step up shifting, Normal clutch operations to get the vehicle moving, and then depressing the clutch, move to a desired gear ratio, and letting off on the clutch to engage gear. As many times up or down shifting as the driver sees fit.
3. Flow manual shift(?), not excacly shifting. Once vehicle is moving, the driver can flow through the entire spectrum of the ratios available (just like what the hardware does for the the CVT, in some cases invlolving a quik change of gear or downshift), the driver can add personality to the vehicle's responce.
These three methods that can work all together and every which way.
EX: Driving through traffic in auto, then getting a chance to pass some one, turn off auto and downship yourself using the clutch or not its up to the driver.
My first proto-type may not include the CVT's saftey peramiters allowing me to really test (or break) the method of driving. Most people have to get accustomed to a CVT, imagine what it would be like if the driver has so much more to do with what the tranny is actually providing?

Hoorah Grease Monkey

 

[808state]

The trouble of all this is;
a change of duty station to JAPAN, whether or not the patent works (i'll do it any way),
and using a torque conveter or not (it will have a manual clutch).

Hoorah Grease Monkey

 

[JayMaechtlen]

"A CVT can be less expensive to construct than an automatic, more versatile than a manual, and can span gear ratios larger than traditional manuals."

more versatile than a manual? An automatic already is.

larger span of gear ratios? well, kinda. Providing you're very careful with torque applied when the ratio goes very high.
Automatics already go from 0 to whatever, if you include the torqe converter.

less expensive? I'll believe THAT when I see it!
(that is, a buildable reliable unit that does the above, and also has a useful efficiency level...)
- well, I guess that does depend on which automatiic you compare it to? I'm sure the new 7-speed Daimler units aren't cheap...


Jay Maechtlen

http://home.covad.net/~jmaechtlen/

 

[808state]

Very true, but Look at the ford 500, and its competetors. Ford has 200 hp gas efficient v-6, and the accura of that class, has 250hp, but the acceleration of the ford is faster+more efficient in gas.
"So what's up with Ford's reasoning to equip these cars with only a 3.0-liter V-6, when competitors offer larger, more powerful engines than this 203-bhp, 207 lb.-ft.-of-torque unit? Largely to achieve good fuel economy numbers (27 mpg highway for the Five Hundred). But these cars don't suffer in acceleration, thanks to the close ratios of the Aisin AW 6-speed automatic transmission and the extremely efficient ZF-Batavia continuously variable transmission (CVT). Both work well in conjunction with Ford's smooth Duratec V-6, and we applaud Ford for using modern technology rather than old-fashioned cubic inches to achieve performance."

-Oct. 2004 Issue of road and track.-

Check out prices for CVT's in their ruling country, "Japan". Only $200-$500 and the savings in gas are better than competetor traditional 4 or 5 speed autos.
True they only power small 4 or 3 cylinder engines, but are making huge advances in CVTs. They have been productively using them for years now.

The gear ratios for CVTs can offer a larger span than (as in), lowest to highest. I dissagree with traditional automatics being more vesitile than a manual. Well, i havent driven one yet anyway.

Hoorah Grease Monkey

 

[808state]

True some automatics are getting very sophisticated, but for mechanics and car enthu. we could care less for sophistication, and want something fun or chalenging to drive.
I cant say i like the CVTs produced in the US (ford 500,Merc Montego) .
The european market looks good (ie mini, audi ect), but Ill stick with the asian scene. The US army has a CVT in some cargo trucks and are thinking of putting one in a tank. The problem is most automobile CVT's cant handle too high of tourque before failing.

Hoorah Grease Monkey

 

[sailsmanroth]

I kind of liken this concept to the propeller pitch control on a turboprop airplane.

It combines an infinite gear selector and a clutch, into a 'Jaguaresque' autotrans gear selector.

Think: An F1 race(or ALMS, or Rolex Series). And: How could it take me around the course quicker? If there's no positive answer in this(these) environment(s), you're selling a dead horse in the automotive industry.

Doesn't mean your idea is faulty, just the application may not be for the automobile. Just a thought, to think about.
marty

 

[Lankreijer]

I read this thread and I hope I can add some valuable ideas.

Patprimmer, you mentioned the dutch car Daf (later build by Volvo). It is true that this this (belt)drive uses cones. The adjustments to the gear ratio is by a mechanical regulator (those things with two balls that vary their distance by different rotational speeds) that will dictate the distance between the two cones of one side.

I do not know whether this system is still in use, but will have some advantages. The desired drive mechanisms by 808state are very simple to accomplish with the above mentioned system. The clutch can be left out and the mechanism can be placed on one of the sets of cones (the other will follow the motion of the regulated set of cones because of the constant length of the belt). Just make an adjustment to the mechanical regulator (mechanic, hydraulic or electric) that it is possible to change the distance between the two cones with a constant regulator position.

Hopefully this description is clear enough to understand. If not, I will try again later.

 

[Warpspeed]

Marty, in Formula One racing there are a lot of things that could make the cars faster, but are simply not allowed by the rules. ABS would be one, and a clutched automatic controlled by a microprocessor probably could too.

The theory being that anything that greatly reduces the need for driver skill is not good for the sport.

 

[NormPeterson]

Somewhat more closely related to normal road cars, the theoretical advantages of a CVT are tacitly understood by the SCCA, and in their Solo II rules CVT acceptability is limited.

The best example I can give is for Prepared category cars, in which there is considerable freedom to modify regular production cars. The only options to an unmodified stock transmission that are permitted are "any non-sequential manual transmission", "Any automatic sequential transmission employing a torque converter", and "Electrically-controlled overdrive transmissions". And the way the rules are written, you can't source a stock CVT and swap it into a vehicle that was not available with that particular one as OE.

As conservative as sanctioning bodies tend to be when it comes to writing rules, I think it will be the average consumer side that will drive this technology. I can see it making a lot of sense in vehicles like the Murano, where you'd select a generally lower range for whatever off-roading you might do with it, or for driving any 4000# vehicle in the mountains where you might want more gear for either side of the hill.

Norm

 

[808state]

Through out my research I did see something about new regulations on the type of trannies available for f-1 and other racing vihicles... I think siesmonic or triptronics were being considered for future use. The tanssmissions going through a strict screening and such before eligble to race. If I can find the source to which I seen this i'll share.

Side note: I'm staying in california and will be stationed in Camp Penelton , going to Iraq, poland or europe on deployments in the next three years. This will be good for me because i'll earn the extra cash to kick off this project full scale. The new civic si by honda will be my victim of modification. If it spoofs i'll convert it into a 5 speed like it was, and see if any one picks up on the idea later.

Hoorah Grease Monkey

 

[808state]

Hey its been awhile, but my LCPL connection has got me a helo (HELICOPTER) throttle controller. my contacts and connections are finally working for me............ the only problem is i'm going to IraQ in september and that will either kill me or give me enough money to send this project rolling. I'll take the mesurements to fit the unit in a vehicle and fit that vehicle with a CVT tranny that will allow manual control. hard? not at all! in GSE we can use free gas/diesel, free usage of tools and other equipment payed by tax dollars. Not bragging but a good cheap way of gettin g what i want before hitting the fog of war.

Hoorah Grease Monkey