Is there any Positive / Non-friction Continuously variable transmission....?

Although your question probably relates to automobiles, this is something bicycle innovators have been seeking for years. The gear ratio changes of the recently unveiled "Stringbike" are stepped, but the drive mechanism seems to contain the possibility of an infinitely variable non-friction transmission (Google "Stringbike").

The simplest solution is a differential with two motors, you can obtain any rpm in given domain defined by the motors as well in positive as in negative direction and even zero speed with both motors running.

Hi Nickname, could you please elaborate a little for my understanding.

If you have other questions please ask

Nick name, Thanks for that. But this is Not a all mechanical CVT. combination of motor and engine (ex: toyota prius) produces the CVT. taking variable speed input from motor produces the variable out put.

Is it possible to find a simple solution for what you seek ? The definition of your request is: " appositive continuous speed variator". You ask as well for system which does not use friction for the transmission. May I suggest following analysis so that the problems of such a solution will be –according to my opinion – made clear. A continuous speed variation means that a least one of the distances can be modified in a "continuous" way i.e. the axis of this component can take ANY position along the radius between the 2 rotation centers. For me a rotation center is the intersection of the axis around which the element rotates with the plane in which the 2 components mesh with each other. Definitions are important to avoid misunderstandings. If friction is to be eliminated as possibility then only a "geared" meshing can be used. Both components will have a fixed number of "teeth". The circular pitch i.e. the distance between two adjacent teeth measured on the primitive circle will be the 2*π*R/z where R is the radius of above mentioned circle and z the number of teeth of the "gear". For a correct meshing the arc length on the first "gear" MUST be equal to the arc measured on the second "gear". But this one has a different radius R2 and thus the arc length will have to be L= 2*π*R2/z2 = 2*π*R1/z1. From this equation it comes that NOT only the radius has to be changed but also the number of teeth! One can imagine that not the number of teeth will be changed but only the angle between 2 adjacent teeth in the meshing zone. This means that the "teeth" elements of second "gear" have to move radially and for at least a limited angle as well in tangential direction! The problem is that all this system MUST transmit the tangential forces in order to assure the torque transmission. You see that under such constrains it is NOT possible to speak about a positive transmission which presumes solid components. Of course a lot of COMPLEX designs can be possible and what was presented is one of the potential solutions if the 2 conditions are satisfied at SAME time : displacement in radial AND tangential direction. For a load transmission the stiffness of the system has to be adapted to the load magnitude since deflections lead to meshing problems, wear and noise. Geometrical precision has to be very high, quality gears have pitch and profile deviations in a limited number of µm. The schematics I looked at the suggested site show that a pitch variation is possible but I do not see the radial variation and I presume that there are a lot of other elements than what is displayed. Those thoughts lead me to the assumption that the solution may be very good for kinematics but les usable for power transmissions. This does not reduce at all the value of the idea. In industrial power transmissions one of the important factors is their reliability or it is known that the more elements are in a chain the higher is the failure risk. This has as well to be considered. What I suggested is a possibility to have a continuous positive speed variation with the lowest number of components. It is already used either with only one motor and a "slip friction" element to simulated second one or for instance with an IC engine and a combination variables hydraulic pump + motor as second power source.

Hi, my name is Graeme John Eddington from Perth, Western Australia. I have invented an IVT using three(3)planetary systems made with constant-mesh chains and sprockets; Australian Innovation Patent No.2012100212. The issue I have with direct-drive (D/D) transmissions is the ratio of the transmission has to match the speed of the vehicle - in my transmission, the speed of the vehicle determines the transmission's ratio. The simplest way of creating an IVT is by NOT having a direct-drive (D/D) in the power train. By using sprockets and chains, each planetary system can have a different sized sprocket in the center running on individual coaxial shafts. This means each planetary is turning at a slightly different speed, plus, the carrier can vary in speed because it is not connected to anything producing an overall variation in the input and output speeds. It amazes me how complicated some of the systems I have seen are, insisting on using gears and maintaining the dream of a direct-drive (D/D) transmission. I have achieved this by using only three(3) simple chain driven planetary systems. Graeme J. Eddington. Patent No. 2012100212.

The only working continuously variable transmission I know of is a toroidal system you might try a search for Torotrack

That's true. I am actually using a differential to get overdrive. My multiple-input Infinitely Variable Transmission also has 2 outputs which I am feeding into a differential so when the crown wheel drives the pinion gear it give me overdrive - the opposite to what is normally the case. Take a look at the Australian Patent No. 2012100212 by Graeme John Eddington. If you would like to purchase the instructions on how to build your own Mechanical Torque Converter, email:- smart-s-trans@hotmail.com - The Patent only shows the reduction mechanism. A document needs to be signed before instructions sent.

http://www.zero-max.com/adjustable-speed-drives-c-21-l-en.html

Hello guest, its not a positive type.. its a friction based. Its also not a true CVT!!

I had a look at the address you mention. I find the idea VERY interesting.

It has on my opinion a rather high degree of complexity and complexity is always related to wear and failures. But for some applications the idea is good and worthwhile to develop. I think especially at low power applications and moderate to low torque moments may I say more kinematic than power transmissions. One of the problems is the "meshing" between the teeth extremity and the internal profile. Due to the radius changes the meshing conditions will change and the loading at the contact region also. The design could be quite complex as well. This is the rason I more consider the feasibility possible for low power. GOOD IDEA

John, I read followed that link in google and went through your design. I need few clarifications. 1. How do you change the radius of the adjustable spur gear? 2. How do you achieve the precise adjustment of the spur gear to match the gear meshing with the internal gear? Let me know if there is any animation/ video of the design so that the mechanism can be understood well. thanks

would be happy to review the design. i am reachable at

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Thanks

Dear TriOZ,

Thank you for your offer to review my CVT design. To expedite this, please do a Google search on 'continuously variable transmission john pellegrino' and go to the second link which is entitled, 'Hybrids in Motion' and read down to the paragraph entitled 'Talkback'.

Hope to hear from you soon.

John Pellegrino

What about the Daf Variomatic gearbox?

What about the dérailleur gears used on bicycles?

I think there is no positive / non-frictional continuously variable transmission becase It can only happen in ideal case. Friction can be reduced but cannot be removed completly........

I hate to rain on your 500 year old party of non-believers but you can have a Positive Drive / Non-friction Continuously Variable Transmission. I achieved it in 2010 when I build my first prototype of s-trans (a Torque Transfer Device) but I had been sitting on the idea since the early 1990's. Sorry to take so long but inventions do not pay the mortgage, they eat money rather than produce it. What I noticed was that all the CVT's out there, attempt to transfer POWER rather than TORQUE. Now, I do know that they go together, but it is what they focus on that is important. What s-trans does is very similar to a hydraulic torque converter but does it mechanically and works like the '3-speed' part of an automatic works but without the hydraulics. To achieve this a needed to have sprockets and chains but with no friction components, no ratchets and no hydraulics. I hope you like it, go to: www.strans.wordpress.com for further details. My name is Graeme John Eddington and I live in Perth, Western Australia. Please comment. I have only just lodged the Patent so I cannot refer you to it yet but I am willing to discuss what's in it, if you are interested to know more.

We're of course interested & the focus of interest is how

your explanation of the features

As I several times wrote there is a german proverb: "paper is patient". You may write any thing you want on paper and it will not go upset. The fact that you obtain a patent is not a guaranty that it also works only that it is not similar to an other request and that it does not claim to genrate power from nothing.

So that after reading your "further details" I can only say: present either the working model or the (as far as you can ) principle and till you do so I am sorry but although very much interested I do not believe it is possible. If you read my comment above you will understnad that I analysed the problem and and tried to give a correct explanation for the impossibility as presented by the original OP.

I expect your input and if it is correct I shall be glad to congratulate you.

As Garthh and nick name have both said - there is no point in claiming something like this with no proof at all. There are quite a few companies and individuals worldwide who claim to have positive engagement variable ratio arrangements - but all are bogus.

If you have solved the variable gear puzzle - well done, you are the cleverest bloke in the world - but I remain doubtful that you have.

Daf Variomatic gearbox is friction based CVT. dérailleur gears is Not CVT. its a step by step gear transmission.

Possitive non friction CVTs have always been an object of desire for inventors.

Many of you are good engineers but possibly not so good inventors.

For example: Just at this very moment it came to my mind the following

You can move one solid with another solid by friction in a frictionless way, simply by increasing the force between solids so much that any relative motion becomes impossible. Or by using gear teeth. No motion= No losses Except vibrations.

Imagine a wheel that touches a straight bar, without slippage.

The efficiency will be close or higher than in a geared contact,.

If you do not like this, susbsttute the wheel for a gear and put teeth to the bar

This bar is connected to another bar through a variable ratio 3 point lever

And this second bar moves another wheel. The motion has to be of course oscillatory (Some small inertial losses here).

As for te losses during wheel to bar "Engagement", we may note that usually power transmissions change velocity at a small rate.

So from one oscilation to the next, the speed differential between bar and wheel will be always small.

If we use gear and toothed bar, then a small energy conserving spring can absorb the small velocity differences during engagement

This transsmission I have just invented, may be as good as a geared one, because it is based on solid to solid transmission without slippage.

And it is a nonfriction CVT.

Chorete

I did not have time to rethink it

Trioz- a very interesting question and one I have worked on (unsuccessfully) for many years (in an amateur capacity).

I think the simple answer is "no" - there is no such gear system. Is there such a system waiting to be discovered? - it is hard to say. There does not seem to be any law of mechanics, physics or nature in general that precludes such a system but nobody has found one in the last five hundred years or so.

If Pellegrino's system is the same as the one on the internet - it doesn't work and it is not even a good attempt.

Kelpiecross, I feel that positive in nature comes with a pocket like. The mode of power transmission is not continuous in nature. Like you say gear teeth, or sprocket chains. But when it comes to hydraulics, the medium of power transmission is liquid which is maintains continuity!! So, i see stil there is room for use to think on continuous medium of power transmission which is also positive type. for some time, i worked on power transmission by helical path of a chain/belt. which works positively, but the belt keeps shifting side words. Other way of doing it it is a flexible belt getting locked to spokes.. (like a snake going in between a line of some spokes). Theoretically its possible.

TriOz - I presume you are from the Land of Oz - me too.

I am not talking about hydraulics etc. as a means of positive variable transmission - clearly they work. But gears, chains etc. are a different matter - a much trickier situation. I can't really comment on your system from your description - perhaps you would like to contact me privately with more details. (I think there is an internal message system). Da Vinci couldn't do it, nobody has been able to do it in the 500 years since - so if you have done it - you are bloody clever.

I would like to see your idea.

Kelpiecross, Please check your inbox. I have a sent you a mail.

Hi Kelpiecross,

Please check your mail box.

Regards

TriOz

Hi TriOZ,

I'm happy to answer "YES" to your question!

I have a well working prototype there:

http://yves.maguer.free.fr/home/CVT_fort_couple.html

I dont want money.

I have no patent! I'm looking for a very big entreprise, whose able to pay for a patent with my name.

But TriOZ, what do you want to do?

Yves - I don't think anyone can comment on your gear system as you don't seem to have revealed any details of how it works. It doesn't involve ratchets or one-way clutches does it?

In Australia you can apply for a "provisional patent" for about $100 (if you don't use a patent attorney) - this gives pretty good protection for your idea for a year. I would assume that France would have a similar system.

I would be very interested to see your idea if you contact me privately - I promise not to steal the idea.

I apologize to everyone, but a one year protection, "good is not perfect", this is not enough for me. sorry again!

by cons, I can tell you about how it works from outside. and what you can expect in particulars conditions.

I speak around me about patents, and no one is able to win again an world enterprise.

I spend 5 years to search, one month of salary to build it.

i prefer to die with no one who knows how it works rather than being stolen.

I have 800 reader of my web page.

"the time is on my side" lol

I very much doubt that time is for you. You should go to one of the french organizations as CETIM or OSEO in order to get a support and get a patent. They invest in good ideas.

The demo sais nothing and if no one knows what it is then nobody can help you it is a snake eating its tail!

The ptorotype you build appears to be big with respect to the torques you claim. As you may know the trend for many reasons goes into compact transmissions as well for cost reasons as for economy of energy.

Nothing shows that your transmission is contnuous you only use two positions (may be I am wrong) of the rotating control level arm. The fact thet you put as well on input as on output about 1/2 of your weight indicates a 1:1 transmission which is not in fact interesting since a transmission per definition has to be either amplifing or reducing torque. Ratios have to be up to 4..5 for some operations, a i=1 is not of interest.

I analysed many years ago ways to obtain a true "positive" variable transmission and the simplest one was - as other came also to same conclusion- a differential with 2 motors either one or both with variable speed control.

May I add that a "positive" transmission does not transmit torque via friction.

I have the feeling that you use levr arms with a oscillating point variable position. This is a solution but much more complex and cumbersome.

"They invest in good ideas"

how do they recognize the good one, without knowing how it works!!??

take a look again at the video, and think about.

If,in France, you apply for a patent as a private person the fees are low and spread over several years. You also can get from specialised layers at the INPI a free support for the patent redactional work which is very very importnat. So that you can have a protection and are in the position to discus with some state agency. If you do nothing - I assume your idea is good although i do know nothing about it- then it can be possible some body else will have same idea and make the step and all you invested will be lost. You are right if you know nothing you cannot appreciate a solution. As I said time is NOT working for you but AGAINST you. I know what I say based on personal experiences. Nobody will invest a cent for your eyes color, even if they are beautiful!

My other remarks remain valid.

Yves - I agree with what Nickname says. In addition your invention has a major flaw in that it only operates in the one direction. To be a really good variable gear system it must operate in both directions (and be the reciprocal ratio when the output is driving the input - as with a conventional gear set). In general, automotive legal rules worldwide say that a car must not "freewheel" on the overrun.

Keep in mind that the variable gear problem in general is an almost impossible thing to achieve - and it may well be not possible at all. You say that you have worked on the problem for 5 years - many people have spent entire lifetimes on the problem without success. People have been trying to solve the problem since at least the time of Da Vinci's attempt 500 years ago (and his attempt was not very good). There are several University Mechanical Engineering departments that are actively working on the problem plus a few big companies - none show any signs of a breakthrough.

If you have actually come up with a new idea that works you are tres clever.

Hi TriOZ

I have invented a new Positive Engagement, Continuously Variable Transmission (PE-CVT), called Positive Continuous Variable Transmission (P-CVT).

I think this is the one may answer your question.

As Nick Name said "A continuous speed variation means that a least one of the distances can be modified in a "continuous" way". To vary the speed ratio, PE-CVT must vary at least one effective radius. Since the pitch of a gear or a chain cannot be varied, a meshing problem happens and needs to be solved; when the problem is solved, the transmission becomes too low efficient or falls into another problem: the oscillating output, could be another dead end.

A PE-CVT with desire characteristics needs a different operation principle so that it can vary the speed ratio without modifying any distance or pitch diameter.

Positive Continuous Variable Transmission

A P-CVT comprises two parts. The first one is a mechanical assembly called Reactor. A typical Reactor comprises two drive shafts (1) and (2) and three planetary gearsets (3), (4) and (5) that are coupled together. The Reactor is used to create the driving torque on the output shaft.

The second one is a hydrostatic module called Activator using to control the driving torque. The Activator comprises a hydraulic pressure source, a pressure controller, a switching valve and a number of double-acting hydraulic-cylinders (11).

The Activator does not include a hydrostatic motor; the Reactor does not include a clutch; P-CVT is a mechanical PECVT; it does not relate to hydrostatic CVT or use a clutch to vary the speed ratio.

The operation of P-CVT is completely different from all other mechanical CVTs. The V-Belt CVT, Toroidal CVT and the other PECVTs vary the speed ratio by varying the effective radii. P-CVT does not vary any effective radius or any pitch diameter. Instead trying to vary speed ratio, it varies torque ratio between its two drive shafts. In other words, instead of controlling the speed ratio, it controls the driving torque as the electrical drives and the Hybrid Synergy Drives do. While the electrical drives and the Hybrid Synergy Drives uses a power control unit to achieve desire driving torque, P-CVT uses a pressure control unit and a switching valve.

To see how the Reactor able to function at any speed ratio and create the driving torque, how the Activator controls it and how P-CVT improves both the driving performance and the gas mileage please visit:

https://sites.google.com/site/pcvttang/

Duc-Quang - Could you explain the basic concept of your system in a much simpler fashion? There is an awful lot to read through at present.

Hi Kelpiecross

Thank for your interesting.

P-CVT has two parts: a Reactor and an Activator. The Reactor comprises an input shaft 1, an output shaft 2 and three gearsets 3, 4 and coupled together. Gear 32 of the fixed gearset 3 connects to gear 41 of the planetary gearset (PG) 4; gear 42 of the PG 4 connects to gear 52 of the PG 5; gear 51 of the PG 5 is keyed to shaft 1. Gears 32 and 41 are mounted on the carrier 6 that is fixed on the transmission case 10. Gears 42 and 52 are mounted on the carrier 7 that connects to shaft 2.

The gear ratios of gearsets are calculated so that at any speed ratio between shafts 1 and 2, shaft 1 and the input of the gearset 3 always rotate at the same speed.

The Activator comprises a hydraulic pressure source, a double-acting hydraulic cylinder (HC) a switch valve and a pressure control to vary the forces at the two ends of the hydraulic cylinder. One end of the HC is mounted on an arm that is keyed to shaft 1; the other end is on gear 31 of the gearset 3. This causes all the gearsets of the Reactor are coupled in a complete circle. When the hydraulic pressure applied on the HC, the HC produces two opposite torques: one on gear 31, the other one on shaft 1. The torque on gear 31 produces a torque on gear 32, then 41, 42, 52, 51 then shaft 1 against the torque provided by the HC. The strengths of the torques on the gearsets are controlled through the pressure control unit.

As a torque applying on gear 41, it produces a torque on gear 42 and another torque on the carrier 7. Similarly, as a torque applying on gear 52, it produces a torque on gear 51 and another torque on the on the carrier 7 but in opposite direction. The different between them is the driving torque on shaft 2.

The special arrangement of the gears 41 and 42 allows the two shafts 1 and 2 can rotate at any speed ratio and the pitch diameter of gear 42 is smaller than gear 52. That causes the difference between the torques performed by the PGs 4 and 5 on the carrier 7 and result the driving torque on shaft 2.

The strength and direction of the driving torque on shaft 2 can be controlled through the pressure control unit and the switching valve i.e. increasing or decreasing the hydraulic pressure will increase or decrease the driving torque; switching the inlet port at the hydraulic cylinders will change the direction of the driving torque; when the pressure is zero, the transmission functions in neutral mode.

That is the way the P-CVT performs and controls the driving torque.

If I understand what the schematics are the change is due to a sine/cosine effect of th friction vector. If friction is used it is NOT a positive CVT since in the contact regions there is a sliding which you control and use for tangential speed variation.

Please correct if I am wrong.

Hi nick-name

The sliding at the contact regions between the gears is an undesirable factor that should be minimized (by reducing the crossed angle c). Even the slippage effects on the tangent speeds of the gears, it is not used to control the speed variations.

On the diagram 1, V51 is the tangent speed of the center of the contact region (CCG) on gear 51. When shaft 2 is stationary, V52 is the CCG on gear 52. The tip of V52 must always stay on a line passing the tip of V51 and parallel to the helix cut. The dashed line connecting the two tips represents the slippage between the gears. That is how the velocities of a Crossed-Angle gear function.

The tangent speed of the CCG (or contact point P) on gear 42 is V42. To create the driving torque, gear 42 connects to gear 52 and the pitch diameter of gear 42 is 0.5 of the pitch diameter of gear 52. The magnitude of V42 is 0.5 V52.

V41 is the tangent speed of the CCG (or contact point P) on gear 41. The gear ratios of the three gearsets are calculated so that when shaft 2 is stationary, the two tips of the two vectors stay on a line L parallel to the helix cut. V41 and V51 rely on the speed of shaft 1 only thereby they are unchanged when shaft 2 rotates.

When shaft 2 rotates, refer to the diagram 2, the axis of shafts 44 rotate about the central axis and have tangent speed V7. As the axis 44 rotates about the central axis, it varies the velocities V52 and V42. The velocity V52 includes two parts: the first one V52' is caused by the rotation about its own axis; the second one VT on is caused by the rotation about the central axis. Similarly, the velocity V42 includes two parts: the first one V42' is caused by the rotation about its own axis; the second VT' on is caused by the rotation about the central axis. Assume that the pitch diameter of gear 51 is very large thereby VT and VT' are equal to V7.

Since gear 42 connects to gear 52 and the pitch diameter of gear 42 is smaller gear 52, V42' is equal to 0.5 V52' and the tip of V42 moves to line L'. The line passing the two tips of V41 and V42 is not parallel to the helix cut. This causes a meshing problem in case the gearset 4 is an ordinary planetary gearset.

The gearset 4 solves this meshing problem by moving the contact point.

As you can see on the diagram 3, when the axis 44 of gear 42 moves from position 44A to 44B, the contact point P moves from position PA to PB. VP41 is the velocity of the contact point P on gear 41. If you stand on the moving axis 44, you also see the velocity of the contact point P is VP42'. The combination of the two movements causes the contact point P on gear 42 has a velocity VP42.

On the diagram 4, the velocity V1 of the CCG (or contact point P) on gear 41 is the sum of two vectors V41 and VP41. The velocity V2 of the CCG P on gear 42 is the sum of three vectors VP42 and V42' and V7. The additional movement of the CCG P allows the tips of V1 and V2 stay on line L' parallel to the helix cut and solves the meshing problem.

The movement of the contact point does not mean a slippage. In contract, it reduces the slippage caused by the crossed angle C. As the speed ratio S1/2 is zero, the slippage caused by the crossed angle C is zero too.

The movement of the contact point means the gears 42 engage with the imaginary internal ring gear X. To help in imagination, assume that the pitch diameter of gear X is very large and the gear X looks like a rack or a toothed bar as shown in the figure 5. While a normal toothed bar has teeth cut from side to side, the toothed bar X has short teeth formed by the teeth of gears 41. That why the contact regions are much smaller and the crossed angle C needs to be minimized.

On the figure, the green dashed teeth are at the back side of gear 42. When shaft 2 rotates; the gears 42 move down and function as the pinions; mesh and roll on the toothed bar X. Gears 42 are always able to transfer power to gears 41 and gear X through normal forces. The Reactor is a positive drive.

Thank for your interesting question.

Duc - I still have no idea how your system works.

You are not referring to the property of changing the angle between two crossed helical gears changes the gear ratio between the two gears?

Hi Kelpiecross

To vary the speed ratio, the prior PE-CVTs vary at least one effective radius or "at least one of the distances can be modified in a "continuous" way". Since the pitch of a gear or a chain cannot be varied, a meshing problem known as the non-integer tooth problem happens and needs to be solved.

To avoid the non-integer tooth problem, P-CVT does not vary any effective radius or any pitch diameter or any angle between two crossed helical gears. As you can see on the figure 5 above, the crossed angle formed by the axes of gears 41 and 42 is always the same, no matter shaft 2 rotates or not.

The operation of P-CVT is completely different from all other mechanical CVTs. Instead of trying to control the speed ratio as all other mechanical CVT do, it controls the driving torque.

P-CVT has two parts: a Reactor to create the driving torque and an Activator to control it.

The Reactor comprises 3 gearsets in a special arrangement. Refer to the diagram in previous reply; gear 32 of the fixed gearset 3 connects to gear 41 of the planetary gearset (PG) 4; gear 41 meshed with gear 42; gear 42 of the PG 4 connects to gear 52 of the PG 5; gear 52 meshes with gear 51; gear 51 is keyed to shaft 1 and shaft 1 connects to gear 31 by mean of the double-acting hydraulic cylinder of the Activator. This causes all the gearsets are connected in a complete circle.

As shown in the above figure, the double-acting hydraulic cylinders 11 have one end pivoted on gear 31 and the other end on an arm 9 that is keyed on the input shaft 1.

The function of the hydraulic cylinders is often misunderstanding that they turn gear 31 on shaft 1 then change something to vary the speed ratio. P-CVT does not work that way. The Reactor is designed so that shaft 1 and gear 31 always rotate at the same speed no matter what is the speed ratio between its two drive shafts. When hydraulic pressure applying on the hydraulic cylinders, they cannot turn gear 31 on shaft 1 (regardless the backlash). As the hydraulic still applying, the hydraulic cylinders perform two opposite torques: M31 on gear 31 and M1A on shaft 1. The strength and directions of the torque are controlled through the pressure control unit and the switching valve.

Gear 31 meshes with gears 32; torque M31 results the torques M32. Gears 32 connect to gears 41 thereby torques M32 apply on gears 41. Gears 41 mesh with gears 42; torques M32 result torques M42. Gears 42 connect to gears 52 thereby torques M42 apply on gears 52. Gears 52 mesh with gears 51; torques M42 result torques M51 on gear 51. Gear 51 is keyed to shaft 1; torque M51 transfer to shaft 1 against the torque M1A that is formed by the cylinders.

On the above detail view, torque from gear 41 transfers to gear 42 by applying a tangent force F41 on gear 42. The tangent force F41 results torque M42 and a force F7A on the center of gear 42. Since gear 42 is supported on the carrier 7, force F7A applies on the carrier 7 and results torque M7A. Torque M42 when applying on gear 52, it results two opposite forces: F52 on gear 51 and F7B at the center of gear 52. Since gear 52 is supported on the carrier 7, force F7B applies on the carrier 7 and results torque M7B in opposite direction of M7A. The driving torque on shaft 2 is M2 = M6A - M6B.

The strength and direction of the driving torque can be controlled through the pressure control unit and the switching valve i.e. increasing or decreasing the hydraulic pressure will increase or decrease the driving torque; switching the inlet port at the hydraulic cylinders will change the direction of the driving torque; when the pressure is zero, the transmission functions in neutral mode.

The Reactor is also designed so that the two drive shafts can rotate at any speed ratio (from infinity to zero, same direction or opposite directions). When applying on a vehicle, P-CVT permits the engine running while the vehicle is not moving. To start the vehicle from rest, the Activator increases the hydraulic pressure from zero and causes the Reactor perform desired driving torque to accelerate the vehicle. When the vehicle running, the speed ratio changes.

P-CVT does not control the speed ratio. It controls the driving torque to get desired speed ratio as the Hybrid Synergy Drive do.

Hi Kelpiecross

P-CVT is completely new from its construction to operation principle. It took me many months to know how it works. On the web site, I tried to explain about it. However, i don't think it is clear enough. Please do not hesitate to pose your questions. I am always happy to answer.

Kind regard

Hello,

I explain some little things on CVT, and I compare to mine, here:

http://yves.maguer.free.fr/home/CVT/To be or not to be a CVT.html

Today is a good day, I have sended a french patent for ..... a wind turbine.

If within 20 mounths I have a lot of customers, I will thinking for a CVT patent.

Cher Monsieur Maguer,

La lettre dont vous présenter la copie est une manière assez polie de vous envoyer promener. Si vos explications "orales" auraient démontré sans faille la solidité de votre principe la réaction aurait été tout à fait différente car si l'on considère qu' un produit a un marché potentiel réel on essaye de trouver soit des capitaux soit des partenaires pour le promouvoir. A votre place je ferais d'autres essais avec des sociétés fabricant des réducteurs ou autres types de transmissions mécaniques qui auraient intérêt à se diversifier.

Non, nick_name, ce client exploite un marché de niche et ne veux pas aller sur d'autres marchés.

par contre j'ai déposé le brevet.

I have a patent for my invention.

If no one want to buy me some time before I show how it works, I will explain the system.

I explain how it works, one drawing per day.

There: http://yves.maguer.free.fr/home/CVT_fort_couple.html

Hi TriOZ !

are you satisfied??

Yves - your "solution" to the age-old variable gear puzzle involves a ratchet (or one-way-clutch) and is thus not a valid solution. There are many "solutions" involving ratchets - some you can actually buy.

"not a valid solution": who are you to decide this?

My proto works fine! lets look:

http://www.youtube.com/watch?v=Jdlq3Vuo1ww

Yves - as you say - who am I to decide this? Fair enough question as there are no "rules" that define exactly what would be a genuine "variable gear" or what would not. However the groups that are working on this problem (and there are very few in the world) usually define a genuine system to behave just as an ordinary pair of gears would (but with a continuous range of ratios) - that is a rigid mechanical connection between input and output, that the output can drive the input but with the inverse ratio to the opposite direction. Also the "perfect" system requires the output to be as steady in its rotation as a conventional gear pair.

TriOz specified "no friction" (as do other research groups) - a ratchet, even though it is positive in its locking, is considered to be in the same class as "friction" as it can stop and lock in an infinite number of positions. This also rules out self-locking gear arrangements like "worm and wheel" etc. - which although they involve only gear teeth they rely on friction for the positive locking.

If you can design a variable gear system that works in both directions (necessary for road laws as well), is perfectly smooth in output speeds etc. etc. (as above) but relies on ratchets, you will probably be able to interest car makers etc. in it.

My system is not perfect, I never said it is.

But, it is essential to make difference between overcenter and friction.

overcenter is when there is no movement between parts.

Friction is when there is movement between parts.

Friction generate heat, overcenter doesnt.

loosing heat means loosing energy.

My system uses overcenter and do not loose energy by friction.

The main default of my prototype is homokinetic.

This is partially solved by the "3D" machine.

I'm currently trying to solve the homokinetic problem. This problem has been already solved for the engine since tens's of years !!!!!!

Dear All,

My sincere apologies to have come on this topic almost at the dusk of it.

Almost 3 years its been since i logged in and today when i checked all your comments, My heart filled with lot of gratitude for all you guys...

Nick name is fantastic, I love the way of articulating the answers. I promise to keep in touch now on.

Kelpiecross has kept the topic wonderfully alive encouraging new possibilities... thanks for that... I am just delighted to see all your conversation so far....

Thank you TriOz - very kind. Oddly enough I think there is a way of achieving an all- mechanical variable ratio system (at least in theory). This doesn't quite meet all the criteria I wrote about in Post 52 - but is probably as close as anybody will ever get to such a system.

I read once that somebody's opinion on the subject was that any variable ratio torque transmission system that was totally stepless must be defined as being analogue in nature whereas anything involving gears or chains etc. must be digital - thus a stepless variable ratio system involving gears etc. must be impossible.

However there is one common kind of mechanical gear system that is both digital and analogue - and this system can be used to produce a theoretical stepless variable ratio system.

my system is purely analog. gears not detract from the fact that it is analog.
it works so well that I prepared another on the same principle but with a lot more possibilities. I will explain its operation after the filing of the patent.
by cons if expliquations provided herein: http://yves.maguer.free.fr/home/CVT_fort_couple.html not enough you explain how, tell me, I will correct!
the principle:

"d" is proportional to the transmission ratio between "A" and "B", on a portion of a turn. If "d" = 0, A / B = 1.

there is no digital!

I agree.... there has to be a way out. Many a times... i imagine the gears in the shape of snail shell... having the teath cut on its surface... so i get both steps and the smooth radii transion... just my illusion.

Hi Everybody,

It sounds very grand when I want to say this, that I may well have conceptualized the first truly positive-engagement CVT. I have had numerous ideas for a friction less CVT right from my childhood, but a sudden spark a month back gave me a new direction to navigate. I have checked, double-checked and triple-checked since then, and am quite satisfied that it will work, and so am moving on to the prototyping phase.

I know this may sound like a hoax, so therefore, please feel free to ask any question that you may want answering to validate the idea.

And any pointers on whom to best approach in this situation, to take the materialize the invention would be well appreciated.

I know this is a quite old thread, but keeping my fingers crossed. :)

Thanks!

Ashley - I would certainly like to find out more about your idea as positive engagement CVT has been an interest of mine for many (too many) years.

Thanks Kelpiecross for your interest. Some of the checklist items that I tested myself with are:

1. The CVT operation must be truly stepless
2. The CVT operation must not offer leeway for any slippage whatsoever, between the input and output shafts.
3. The CVT actuating mechanism must be soft and easy. That is, it must not require too much force to change the ratio, when under load.
4. The CVT output must be linear
5. The CVT must be capable of reverse operation
6. The CVT must not allow free wheeling
7. The CVT ratio must be modifiable regardless of the RPM, and the rotational position of the input and/or output shafts (Some CVTs allow ratio modification only within one discrete rotation of the input shaft)
8. The CVT must be scalable and able to be designed to handle any amount of torque and power
9. The CVT must be capable of being used as an IVT

So far, I have satisfied myself with all these points. do you have any similar checklist points to be sure that the what I have conceptualized is indeed a CVT.

Also please free to ask some probing questions to which I will try my best to answer without revealing too many details, since I haven't yet applied for any patent.

Your list seems pretty complete - but - does your idea involve friction - even in the form of the self-locking metal-to-metal/all gear teeth etc. worm drive or similar arrangement? No ratchets?

Personally I would find it difficult to comment without actually knowing the proposed principle. Maybe a personal message? I promise not to steal your idea.

So no, there is no metal on metal friction, or special gears like the worm gear. In fact the only gears used are simple spur or helical gears. If worm gears had been used, then it wouldn't have been capable of reverse operation.

And no, it is not a ratcheting mechanism as well, although i can say that it uses one way clutches that lock in one direction to transmit the torque and freewheel on the other.

I have also sent you an IM. :)

There seems to be a flaw in my design in its capability of supporting​ reverse operation. It now seems like I hadn't thought that through to the end. I'm working on trying to correct it.

It was pretty great for a couple of days thinking that I had at last found out the holy grail of transmissions! :) But I'm hoping there's a solution to the specific issue that I've encountered. Keeping my fingers crossed..

Hi All

I have corrected the flaw. The CVT is now capable of supporting both forward and reverse operations.

I have started the process of building a prototype. If any of you are interested in knowing more about it or partnering with me in bringing it to market, please IM me.

Regards

Ashley Lionell