PLANETARY PUSH-PULL ELECTRIC MOTOR

• US 20140184002A1
• Filed: 03/15/2012
• Published: 07/03/2014
• Est. Priority Date: 03/16/2011
• Status: Active Grant

• Current Assignee: Design Concepts, Inc.
• Original Assignee: Asaf Levin, Shalom Levin
• Inventors: Levin, Shalom, Levin, Asaf
• Granted Patent: US 9,570,956 B2
• Time in Patent Office: Days
• US Class Current: 310/90
• CPC Class Codes: H02K 41/06 Rolling motors, i.e. motors having the rotor axis parallel to the stator axis and following a circular path as the rotor rolls around the inside or outside of the stator ; Nutating motors, i.e. having the rotor axis parallel to the stator axis inclined with respect to the stator axis and performing a nutational movement as the rotor rolls on the stator
• CPC Class Codes: H02K 7/08 Structural association with bearings
• CPC Class Codes: H02K 7/116 with gears

Abstract

A planetary push-pull electric motor comprising a ring stator fixedly mounted on the central axis of the planetary push-pull electric motor; a planetary rotor arranged to be magnetically movable around an inner circumference of the ring stator, the planetary rotor rotatably mounted on an eccentric rotor axis in respect to the central axis of the ring stator; a series of electromagnets radially mounted about the ring stator for generating magnetic fields; and a means for transferring rotation of the eccentric planetary rotor axis to directly power an output shaft, wherein when the series of electromagnets are activated, the planetary rotor is magnetically impelled to pivot and roll from one temporary, moving contact line to an adjacent one, creating a rotary moment upon each of the temporary, moving contact lines, providing a power output.

Claims

1. A planetary push-pull electric motor (hereinafter:

“

PPPEM”

) comprising;

a ring stator fixedly mounted on a central axis of said PPPEM, wherein said central axis defines a centerline of said ring stator;

a planetary rotor arranged to be magnetically movable, rotatably mounted on an eccentric rotor axis in respect to said ring stator centerline;

a series of electromagnets radially mounted about said ring stator centerline for generating radial magnetic force upon the magnetic fields of said planetary rotor when said series of electromagnets is activated,

a means for transferring rotation of said eccentric planetary rotor axis to directly power an output shaft of said PPPEM

wherein when said series of electromagnets is activated, radial push-pull magnetic forces are generated, magnetically impelling said planetary rotor in proximal radial contact with at least one electromagnet in said series such that said planetary rotor pivots from one of said proximal tangential contact to an adjacent one in sequence, effecting a continuous rolling motion of said planetary rotor about said eccentric rotor axis and creating a rotary moment, such motion being translated into rotational motion which, when applied to said output shaft of said PPPEM utilizing said rotation transferring means, provides a source of power output from said PPPEM.

2. The PPPEM of claim 1, wherein said ring stator and said planetary rotor are gearless.

3. The PPPEM of claim 1, wherein said ring stator comprises an internally toothed stator ring-gear and said planetary rotor comprises a toothed rotor gear that mesh with each other and act as a planetary gear set.

4. The PPPEM of claim 2, wherein said gearless planetary rotor is radially loaded upon said ring stator and provides a zero backlash friction drive mechanism.

5. The PPPEM of claim 2, wherein said planetary rotor rotates in an eccentric movement about an inner surface of said ring stator in tangential friction contact therewith via at least one friction ring provided on the outside surface of said planetary rotor and disposed so as to be coaxial with said rotor axis.

6. The PPPEM of claim 2, wherein said PPPEM is a planetary friction motor comprising an internally mounted, friction, planetary rotor in contact with an externally mounted, gearless stator, said planetary rotor being directly connected to a lead screw at a proximal end, and to a ball joint at a distal end allowing for free rotation of said planetary rotor and attached lead screw, said lead screw being provided with a movable nut mounted thereon such that said movable nut is impelled to travel along the length of said lead screw in either direction.

7. The PPPEM of claim 1, wherein said rotor axis is radially loaded upon said stator such that the pull forces pull said planetary rotor toward said stator in order to ensure zero backlash when said planetary rotor and said stator are equipped with toothed gear.

8. The PPPEM of claim 1, wherein said rotor gear is mounted on a flange provided with an anti-backlash mechanism.

9. The PPPEM of claim 8, wherein said anti-backlash mechanism comprises a balanced pair of compression springs.

10. The PPPEM of claim 8, wherein said anti-backlash mechanism comprises a balanced pair of screws and associated locking nuts.

11. The PPPEM of claim 8, wherein said anti-backlash mechanism comprises a balanced pair of radial magnet-rings which produces a constant attraction force between said planetary rotor and said stator.

12. The PPPEM of claim 1, wherein said push-pull magnetic forces generated by said series of radially oriented electromagnets interacting with a radial rotor magnet produce vectors which are radially directed inwardly toward and outwardly about said rotor axis.

13. The PPPEM of claim 1, wherein the axis of said planetary rotor is parallel oriented with the axis of said stator, but has a radial degree of freedom.

14. The PPPEM of claim 1, wherein the axis of said planetary rotor is radially loaded toward said stator in order to keep said planetary rotor idle when said PPPEM is not operating.

15. The PPPEM of claim 1, wherein the axis of said planetary rotor is radially loaded upon said stator in order to create a given friction between said planetary rotor and said stator.

16. The PPPEM of claim 1, wherein said radial load comprises a tubular, bearings element.

17. The PPPEM of claim 16, wherein said tubular, bearings element comprises:

a compression spring;

a spring shoe element driven by said compression spring;

an eccentric rotor cam shaft for housing said compression spring and spring shoe element; and

bearings rotatably confined within an inner and outer tube of said tubular, bearings element, and accommodating said cam shaft, said compression spring, and said spring shoe element within a hollow core of said tubular, bearings element,

wherein when said compression spring compresses said spring shoe element mounted within said cam shaft, radial force is applied against said planetary rotor gear for positive, gear-tooth meshing with said stator ring-gear without backlash.

18. The PPPEM of claim 16, wherein said tubular, bearings element comprises:

an eccentric rotor cam shaft;

a pair of flexible couplings connected to a respective pair of flanges; and

a connecting rod mounted between said pair of flexible couplings through respective flanges thereof,

wherein when said planetary rotor rotates, said rotor axis is shifted so as to be coaxial with said stator axis, said PPPEM provides direct power output through said output shaft.

19. The PPPEM of claim 1, wherein the pull forces pull said planetary rotor toward said stator and produce a given friction force between them.

20. The PPPEM of claim 1, wherein only a segmental portion thereof comprises said PPPEM.

21. The PPPEM of claim 20, wherein said segmental portion has at least two segments of said radially mounted electromagnets on said stator while virtually maintaining the planetary gear ratio as in the whole of said PPPEM.

22. The PPPEM of claim 1, wherein said PPPEM has a low gear-ratio of about 1:

4.

23. The PPPEM of claim 1, wherein said PPPEM has a high gear-ratio of about 1:

500.

24. The PPPEM of claim 1, wherein said planetary rotor comprises a primary planetary gear in mesh contact with said stator gear, and a secondary step-gear integral with said primary planetary gear in planetary mesh contact with an output ring-gear integrally connected to an output shaft, such that when said PPPEM is operated, said secondary step-gear acts as a reducer, and so as to minimize the offset between said stator axis and said rotor axis to provide a high gear-ratio directly to said output shaft in alignment with said stator central axis.

25. The PPPEM of claim 24, wherein said secondary step-gear, in planetary mesh contact with an output ring-gear, integrally accommodates three rotating elements comprising said planetary rotor, said eccentric cam shaft, and said output shaft, each rotatable at a different speed.

26. The PPPEM of claim 1, wherein said stator, and said planetary rotor act as a planetary gear set, but without any contact between them, said stator and said planetary rotor being kinematically supported by at least one additional pair of planetary mesh gears to maintain the non-contact condition.

27. The PPPEM of claim 26, wherein said non-contact condition strengthens the magnetic attraction and/or repulsion between said stator and said planetary rotor when said stator electromagnets are activated.

28. The PPPEM of claim 26, wherein said at least one additional pair of planetary mesh gears produces and transfers the output torque of said PPPEM to provide said power output.

29. The PPPEM of claim 26, wherein said at least one additional pair of planetary mesh gears is comprised of high-tensile strength materials.

30. The PPPEM of claim 1, wherein said planetary rotor comprises a soft-metal part.

31. The PPPEM of claim 1, wherein said planetary rotor comprises at least one permanent magnet.

32. The PPPEM of claim 1, wherein said planetary rotor further comprises a series of radial tube-magnets, where all similar poles are similarly oriented in one of an outward direction and in a direction towards said planetary rotor axis.

33. The PPPEM of claim 1, wherein said planetary rotor comprises a one-piece, homogeneous, radial magnet.

34. The PPPEM of claim 33, wherein said radial magnet is formed as a tube.

35. The PPPEM of claim 1, wherein said planetary rotor is formed as a tubular ring.

36. The PPPEM of claim 35, wherein said tubular ring comprises an axial magnet whose magnetic face is directed to be in close proximity to a U-shaped electromagnet.

37. The PPPEM of claim 36, wherein said magnetic face of said axial magnet is oriented in an outwardly radial direction so the flow of the magnetic flux therefrom merges radially with the magnetic flux in the core arms of said U-shaped electromagnet.

38. The PPPEM of claim 36, wherein said axial magnet is provided with a magnetic elbow guide to direct the flow of the magnetic flux from the face of said axial magnet in an outwardly radial direction so as to merge radially with the magnetic flux in the core arms of said U-shaped electromagnet.

39. The PPPEM of claim 1, further comprising an internally mounted, output step-gear.

40. The PPPEM of claim 1, further comprising an externally mounted, output step-gear.

41. The PPPEM of claim 1, wherein said push-pull forces, when simultaneously activated, enables accurate control of said planetary rotor position in and about a steady state condition when aiming, following, and acting as a slave to a target.

42. The PPPEM of claim 1, wherein the planetary mesh gears have a diameter larger than the diameter of said planetary rotor.

43. The PPPEM of claim 1, wherein the planetary mesh gears have a diameter smaller than the diameter of said planetary rotor.

44. The PPPEM of claim 1, wherein said planetary rotor and said stator provide given output torque that varies depending on the diameter of their associated gears.

45. The PPPEM of claim 1, wherein said rotor shaft and an associated cam shaft comprise two, independent, output shaft elements, each rotatable at a different speed than the other.

46. The PPPEM of claim 1, wherein said rotor shaft comprises a load output shaft which rotates at a relatively low speed.

47. The PPPEM of claim 45, wherein said associated cam shaft rotates at a relatively high speed.

48. The PPPEM of claim 45, wherein said associated cam shaft accommodates an add-on device selected from at least one of a low-torque electrical brake, an optical encoder/resolver, and a combination of the two.

49. The PPPEM of claim 1, wherein both push and pull forces acting at the same time impel said planetary rotor to rotate in one of a clockwise and a counterclockwise direction.

50. The PPPEM of claim 1, wherein a serial connection is used to connect between two oppositely disposed electromagnetic coils when acting at the same time.

51. The PPPEM of claim 1, wherein a parallel connection is used to connect between two oppositely disposed electromagnetic coils when acting at the same time.

52. The PPPEM of claim 1, wherein at least one magnetic pole at a time of said series of electromagnets can be activated during motor operation to optimize different, changing motor missions including:

speed change, load change, and an energy saving mode.

53. The PPPEM of claim 1, further comprising:

an indicator rotatably connected to said cam shaft, said cam shaft being coaxial with said stator axis;

a Hall Effect sensor mounted on said stator; and

at least one permanent magnet mounted on said cam shaft in proximity to said Hall Effect sensor,

wherein, when said PPPEM is operated, said indicator measures relative position in between said cam shaft and said electromagnets, speed and direction of rotor rotation, and magnetic flux of said PPPEM.

54. The PPPEM of claim 1, further comprising:

a coupling rod;

a pair of flexible couplings attached at each end of said coupling rod;

a tubular bearings element for housing said coupling rod and said pair of flexible couplings,

wherein one of said pair of flexible couplings is connected to said rotor through a flange at said rotor offset axis, and the second of said pair of flexible couplings is connected to said output shaft along the central axis aligned with the axis of said stator.

55. The PPPEM of claim 1, wherein said series of electromagnets comprise holding electromagnets encased in ferromagnetic cases so as to concentrate magnetic flux from both magnetic poles towards one active face of each of said holding electromagnets in closest proximity to said planetary rotor when said PPPEM is activated.

56. The PPPEM of claim 55, wherein said holding electromagnets are connected in adjacent pairs via the housing formed by said stator where, in one electromagnet of said pair, the South pole is oriented inwardly and in a second electromagnet of said pair, the North pole is oriented inwardly in alternating sequence so as to magnetically rotate said planetary rotor and operate said PPPEM.

57. The PPPEM of claim 55, wherein said holding electromagnets are provided with soft-iron cores selected from at least one of C-shaped profile cores, U-shaped profile cores, and E-shaped profile cores.

58. A PPPEM with push-pull poles comprising:

a stator comprising an internally mounted stator integral with a stator gear, said stator having a series of electromagnets disposed radially around a stator centerline; and

a planetary rotor comprising an externally mounted, rotor ring integral with a rotor ring-gear, said rotor-ring and rotor ring-gear being eccentrically aligned in respect to said stator central axis,

wherein when said series of electromagnets is sequentially activated, said rotor-ring is impelled by radial, push-pull magnetic forces to roll about a continuous series of moving tangential contact lines formed by the temporary, sequential, mesh contact between said rotor ring-gear and said stator gear, such that said planetary rotor ring advances around the inner circumference of said stator in a continuous rolling motion providing a source of power output from said PPPEM.