The LiTor is a new device transforming a back and forth movement into a regulated rotary motion.

Have you noticed that the red and white output shaft is always turning in the same direction?

What is well conceived is clearly stated, and the design to explain it arrives easily...

Applications are numerous : gearboxes and clutches for cars, scooters, bicycles and ships of all sizes, electricity generation, no-crank piston engines, absorbers and suspension generating electricity, braking systems, etc.

A major scooter manufacturer has started working on the subject, and one of the leading European bicycle manufacturers is already building a prototype.

How it works

When the rack goes from right to left,

  • the upper blue wheel rotates clockwise and causes the upper red wheel to turn clockwise, which in turns rotates the yellow wheel clockwise,
  • and the lower blue wheel rotates counterclockwise, but it does not drive the lower red wheel because there is a freewheel which does not drive the lower red wheel in that direction.

When the rack goes from left to right,

  • the lower blue wheel rotates clockwise and causes the lower red wheel to turn clockwise , which in turns rotates the yellow wheel clockwise,
  • and the upper blue wheel rotates counterclockwise, but it does not drive the upper red wheel because there is a freewheel which does not drive the upper red wheel in that direction.

So each movement of the rack rotates the yellow wheel clockwise, and moves the vehicle frontwards.

Or course, it is possible to obtain a specific transmission ratio at each stage of the cycle, by using gears with a non constant radius, as shown below.

In all cases, it remains a very simple mechanism.

Latest article on LinkedIn (June 11. 2018)

The simplest gearbox in the world

This gearbox is a Continuously Variable Transmission.

Although it is extremely simple, it may transfer a very high torque, because it uses only gears. There is no friction and no possible slipping.

A very innovative characteristic is that the transmission ratio may be ZERO, which means it also works as a clutch.

The gear selector may be activated manually or by a computer driven engine.

Applications range from bikes, cars and trucks, to ships of all sizes and very many industrial machines.

This is only one of the many powertrain innovations developed by OPPERTUS.

Patents pending

First Applications

  • Application #1
    Replacing the crankshaft of combustion engines

    The main application of this device is to perform a better conversion between the reciprocating motion of a piston and the rotational motion of the transmission. The torque transmitted by the pistons to the output shaft can become virtually constant!

    It will no longer be necessary to increase the number of cylinders. A 2 cylinders option becomes the maximum for a 2-stroke engine, and 4 is sufficient for a 4-stroke one.

    A motor may now exceed 10,000 revolutions per minute without problems since there is more crankshaft to balance.

    Combustion engines may therefore be more efficient and meet easier the latest pollution standards.

    Other advantages are the reduction of the engine and transmission total weight, volume and manufacturing cost.

    We believe that this system could also make it possible to realize very long-stroke piston engines that could be used to transform hydraulic energy into electrical energy, with a yield that might be even higher than that of turbines.

  • Application #2
    An extremely simple, economical and powerful gear box

    Here is the general outline of its architecture.

    Although very simple, rustic, compact and lightweight design, this transmission offers much more than the best existing transmission:

     1.  a continuous variation of the transmission ratio, forward and reverse,

     2.  a native clutch function,

     3.  and an automatic transmission ratio variation, according to the resistive torque.

    The movement starts at the right of the diagram, the engine rotating the primary shaft, represented as semitransparent to make visible the crank which pushes and pulls the rod (light pink).

    The movement of this rod is sinusoidal because it is driven by a crank that is supposed to run at speed constant but, as explained above, this can be compensated by the shape of the two blue gears on the left side of the transmission.

    This rod rotates the intermediate lever (blue) which in turn pushes and pulls the rack. The rack rotates the output shaft (yellow) at a constant speed shown at the left of the diagram.

    The continuous variation of the gear ratio

    It exists because the small rod (dark purple) leading to the rack can slide to the top or to the bottom of the intermediate lever (blue).

    This makes it possible to tune the amplitude of the rack movement (green). When this dark purple rod is at the top, the amplitude is maximum, and when it is aligned with the rotation axis of the blue lever, it is at the ZERO point. In that case, the rack is locked regardless of movement of back and forth blue central lever. This transmission has a native clutch feature in addition to the continuously variable gear ratio one.

    The automatic variation of the gear ratio

    The crankshaft is sensitive to the resistive torque. One may see that there is a lever inside. This lever may rotate around an axis which is distant from the primary shaft axis. A spring which is not shown on the diagrams tends to align the lever with the axis of rotation of the drive wheel. When the load torque increases, the lever moves away from this position and the upstream end of the pink rod becomes closer to the axis of the drive wheel, changing the overall gear ratio.

    As a result, the gear ratio may automatically depends on the resistive torque. It's an automatic transmission.

    This elastic adaptation has also the function of smoothing the power output of the device, without any flywheel being necessary.

    The reverse continuous variation of the gear ratio

    On the general scheme above, the rack can cooperate either with the two green gears with the two blue ones.

    Each of these green or blue gears cooperates with the axis of the relevant red gear by a freewheel, which is in its center. These free wheels allow the blue gears to rotate in the clockwise direction and the green ones in the opposite direction.

    This enables to have two different rules operations, for example forward and backward. To simplify the diagram, the fork that allows to move the rack to the left or right is not shown. The change from one rule to another may happen only when the rack is stationary, at the ZERO point.

    The rack may also be placed astride blue and green gears. The transmission is then a native a parking pawl that locks the output shaft of the transmission to keep the vehicle from rolling either forward or backward

    This transmission should make it easier to comply with emission standards, but also enables to improve the engine performance.

    At the same time, it will decrease the size, the weight, and of course the price of cars.

  • Application #3
    A more simple and efficient bicycle

    The drivetrain of bicycles has not really been improved since they were introduced in the late 19th century in Europe. It still consists in two pedals rotating cranks that are held in axis by the bottom bracket, using a chain to transmit power to the rear wheel. Derailleurs and hub gears became year after year more complex, and crossover gearing became common, but the overlapping gear ranges results in a lot of duplication or near-duplication of gear ratios.

    All these devices are complicated, fragile, dirty and... expensive.

    Here is the new bicycle, with a much more efficient drivetrain... A simple "LiTor", as described above, becomes sufficient. It is clean, efficient, cost effective and it allows a continuous variation of the gear ratio.

    How it works

    The pedals A and B may move the device either directly (first fig.) or indirectly (second fig.)

    In the first case there is a mechanism that pulls one pedal up when the other one is pushed down, (and reversely), and the user may decide to have short or long movements. In the second one, the pedals are turning as usual and there is a crank shaft (LP).

    In both cases, the M point rotates back and forth around the O point when the user is pedaling, and the transmission ratio varies continuously according the OM distance which is set freely by the user.

    The general design of bikes might change...

  • Application #4
    Rotating tools

    It may be a screwdriver, a key, a hand drill or a circular sander depending on what is put in the tool holder.

    A fast circular movement is obtained quickly by sliding the rack. The handle can also be rotated for a slower but much more powerful movement.

    On top, there is "Pusher" that allows the user to push the tool against the screw or a surface to be modified.

    In one configuration, it screws, and in the other it unscrews.

    View the presentation on LinkedIn.

  • More Applications

    The "LiToR has an endless list of other applications. Just a few examples :

    • very long-stroke piston engines to transform hydraulic energy into electrical energy, with a yield that might be even higher than that of turbines.
    • devices for converting any vibration or random movement into electricity: shock absorbers and cars suspension, waves energy, electricity generators located inside the human body, etc..

    Please feel free to add some other application ideas on LinkedIn.

The video of the first working prototype is also visible on YouTube

All Oppertus technologies are protected by multi-national patents pending or delivered in number of countries.