Roller Gearing and Transmission Technology Pál Bogár sincroll - drive technologies ltd London

1. Roller Gearing and Transmission Technology Pál Bogársincroll -drive technologies ltdLondon

2. Agenda - 45mins • The Innovative Idea- what new do we do • Realisation of the Idea - how do we do it • Design Examples - what variety can we do • Concept Prototype Tests - facts and proofs so far • Benefits and Advantages - why should it be used • Potential Applications - where could it be used • Running Application Projects - who got interested so far • The Sincroll Company - our business, skills and facilities

3. Brand new technology - 8 months in the market Trivial problem – non-trivial solution Rollers connect the wheels wheels do not connect directly there are no “teeth” Rollers roll along the grooves on both wheels simultaneously rigid coupling between the wheels Rollers do pure rolling motion without sliding ensured by the shape of the grooves The Innovative Idea

4. Forces transmit via “single” contact points between rollers and grooves lines of contact points determine the lines of the grooves and the shape of the wheels cross-sectional shape of the grooves is irrelevant lines of grooves are key to ensure proper forces for pure rolling motion Hertzian stress is well contained curvatures of rollers and grooves are similar near the contact point Realisation of the Idea • More like a ball screw than a conventional toothed-wheel gear

5. Complex physics G: roller (ball) P1, P2: contact points between the balls and the wheels gp: path travelled by the ball’s centre when in coupling g1, g2: paths travelled by the contact points u, v: various velocity vectors w1, w2: angular velocity vectors of the two wheels Realisation of the Idea (cont’d)

6. Design Examples The technology is … • universally applicable to any gearing problem • any shaft angles • crossing or non-crossing axes • internal or external coupling • planetary systems and worm gears • linear drives and gear racks • highly flexible and rich in design • for any given gearing problem, provides a variety of solutions • highly optimisable and customisable • very different from conventional • it is more like a generalised ball screw or roller bearing

7. non-intersecting axes axes angle = 90o gearing ratio = 1:1 ball diameter = 4mm contact factor = 8 Page 7

8. intersecting axes axes angle = 90o gearing ratio = 11:15 ball diameter = 4mm contact factor = 9 Page 8

9. parallel axes axes angle = 0o gearing ratio = 12:23 ball diameter = 4mm contact factor = 8 Page 9

10. parallel axes direction of rotation = opposite gearing ratio = 23:25 ball diameter = 4mm contact factor = 19 Page 10

11. non-intersecting axes axes angle = 45o gearing ratio = 1:2 ball diameter = 4mm contact factor = 8 Page 11

12. parallel axes gear rack axes angle = 45o gearing ratio = n/a ball diameter = 4mm contact factor = 16 Page 12

13. perpendicular axes gear rack axes angle = 90o gearing ratio = n/a ball diameter = 4mm contact factor = 10 Page 13

14. internal coupling non-intersecting axes axes angle = 45o gearing ratio = 1:2 ball diameter = 5mm contact factor = 7 Page 14

15. micro-rollers non-intersecting axes axes angle = 45o gearing ratio = 1:5 ball diameter = 0mm contact factor = 8 Page 15

16. The prototype tested was the 1:10 non-intersecting axes, 45o setup Made of steel with nitriding finish of grooves surfaces Test lab at the Budapest University of Technology Tests supervised by the Department of Machine and Product Design Tests performed: All this was done: Basic checks of operations - With and without back-lash Kinematics and noise checks - For both directions of rotation Static power efficiency - For both directions of load Dynamic power efficiency - For various angular velocities Movement precision Reliability Concept Prototype Tests

17. non-intersecting axes T E S T P R O T O T Y P E axes angle = 45o gearing ratio = 1:10 ball diameter = 4mm contact factor = 19 Page 17

18. non-intersecting axes T E S T P R O T O T Y P E axes angle = 45o gearing ratio = 1:10 ball diameter = 4mm contact factor = 19 Page 18

19. non-intersecting axes T E S T P R O T O T Y P E axes angle = 45o gearing ratio = 1:10 ball diameter = 4mm contact factor = 19 Page 19

20. The Test Rig

21. Test Data for Movement Precision

22. Summary of Test Results • Basic operations, kinematics, noise and reliability • no particular issues, performance was quite good in all respect • All tests were insensitive (in terms of statistical significance) to • changing direction of rotation • changing the direction of the load • and whether the back-lash was eliminated or not • Static efficiency at least 98% - this was independent of • roller recycling device being in place or not • back-lash has been eliminated or not (surprise!) • Dynamic efficiency at least 94% • groove surfaces were sub-optimal as a result of nitriding • we will re-test again soon with polished groove finish and improved roller recycling device

23. Summary of Test Results (cont’d) • Movement precision showed a periodic structure where the periodicity was the same as the period of revolutions of the larger wheel in the gear. This shows there was a manufacturing error in the larger wheel. • the error was about +/- 0.2 degrees – looks like a normal amount of inaccuracy and should not be a cause for alarm • we want to retest with a higher precision electronics to see if anything else besides the larger wheel has an effect on precision

24. parallel axes A L U M I N I U M P R O T O T Y P E axes angle = 0o ( n o t t e s t e d ) gearing ratio = 26:23 ball diameter = 4mm contact factor = 8 Page 24

25. parallel axes A L U M I N I U M P R O T O T Y P E axes angle = 0o ( n o t t e s t e d ) gearing ratio = 26:23 ball diameter = 4mm contact factor = 8 Page 25

26. Benefits and Advantages • Power efficiency close to 100% • due to pure rolling motion done by the rollers • sliding friction is practically eliminated • Contact factor up to 20 or more • load distributes over many rollers • Back-lash eliminated • easy to eliminate back-lash by forcing the wheels together • efficiency loss is in-significant … and implications of these

27. High power efficiency No sliding friction Lower energy losses Lower starting torque Smaller motor needed Friendlier to the environment – a green technology Lower operating costs Reduced heating up Reduced abrasion Less cooling and lubrication needed Less wear and deterioration Longer lifetime Less vibration and noise Implied Advantages (Expected) • High contactor factor • Smaller size • Higher power density • Smoother and steadier movements • Precise movements • Lower noise • Greater reliability • No back-lash • Precise movements • Less vibrations and resonances • Longer lifetime

28. Potential Applications • Applicable in all areas of mechanical gearing and power transmission • Including any / high or low: • torque o ratio o precision o rpm o size For example: • High-power drives • due to low operating costs, small size and good reliability • All vehicles • due especially to high efficiency, high power density, special shape and long lifetime • Material handling machines • due especially to smaller actuating torque and reliability • Machine tools • due to eliminated back-lash • alternative to ball-screw drives • Wind power generators • due to high energy efficiency, high gear-up ratio, no back-lash • Standard gear families • especially worm gears and bevel gears due to high efficiency and compact size, respectively

29. Running Application Projects • Car transmission, 5 fwd+1 back • Parallel axes, complex setup • Car rear axle hypoid gears Right-angle • Intersecting axes • Non-intersecting axes • Twin-wheel • Car parts • Window lifter • Engine starter • Truck rear axle hypoid gears • Same as car hypoid gears • Railway traction drives • Same as car hypoid gears • Also parallel axes • Wind turbines • Yaw and pitch drives • Main gearbox • Machine tools • Turning tables • Aviation • Flight control drives/actuators • General industrial • Worm gears • Parallel-shaft gears • Planetary gears • Right-angle “bevel” gears • Linear actuators • Precision drives • Plastic gears • Miniature gears

30. Our primary business of the new roller gear technology research and development commercialisation and transfer Our design and development skills twenty years of experience in scientific research computer aided design and simulations applications design and development, evaluation and testing Our management skills twenty years of experience in scientific research corporate management entrepreneurial and start-up management The Sincroll Company

31. Access to machining facilities manufacture of high-quality prototypes build test equipment and perform basic tests produce on a relatively small scale, pilot runs Access to suppliers local market knowledge supplier contacts, networks and relationships twenty years of experience, track record Wide range of services basic R&D, theoretical and experimental work specifications and analysis, advisory and design prototype and applications manufacture and testing production advisory and outsourcing technology licensing The Sincroll Company (cont’d)