Commutatorless motor

• US 3,883,633 A
• Filed: 02/04/1974
• Issued: 05/13/1975
• Est. Priority Date: 12/21/1972
• Status: Expired due to Term

• Current Assignee: Wolfgang Kohler
• Original Assignee: Wolfgang Kohler
• Inventors: Kohler, Wolfgang
• Primary Examiner(s): Budd, Mark O.
• Application Number:
  US05/438,985
• Time in Patent Office: 463 Days
• Field of Search: 310/12,13AG,40,4MM,152,154,168,181,268,DIG.6 318/138,259
• US Class Current: 310/152
• CPC Class Codes: H02K 29/00 Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
• CPC Class Codes: H02K 99/20 Motors

Abstract

A commutatorless motor having a stator comprised of field poles of constant magnetic field arranged with alternate polarities. One or more coupling coils are arranged between adjacent stator field poles, and an AC voltage source for controlling the motor is connected to such coupling coils. The motor has an iron-free rotor provided with drive coils, with rectifying devices being connected to the drive coils to permit only one direction of current flow therethrough. The coupling coils on the stator provide the only source for driving energy for the rotor, and the rotor coils serve to couple the driving energy to the rotor and as control coils for the rotor. Separate rectifying devices may be provided for each of the drive coils, or alternatively, a single rectifying device may be provided for a group of the rotor drive coils.

Claims

1. A commutatorless motor comprising an iron-free rotor having drive coils and rectifying means connected to the drive coils, and a stator comprising poles of constant magnetic field strength arranged with alternating polarity, pole means adapted to provide an alternating magnetic field and mounted between poles of constant magnetic field strength, and coil means on said pole means, said coil means comprising means for coupling energy to the motor for driving said rotor, said drive coils being the sole coils on said rotor.

2. A commutatorless motor comprising an iron-free rotor having drive coils and rectifying means, a stator comprising poles of constant magnetic field strength arranged with alternating polarities, pole means adapted to provide an alternating magnetic field mounted between poles of constant magnetic field strength, and coil means on said pole means, a source of AC voltage of a frequency greater than the rotational frequency of said motor, and means connecting said source solely to said coil means for applying driving energy to said motor, said drive coils being the sole coils on said rotor, said drive coils being interconnected with said rectifying means whereby said drive coils function simultaneously as energy coupling and control coils.

3. The commutatorless motor of claim 2, wherein said poles of constant magnetic field strength are comprised of a substantially closed ring of constant field strength poles, and said pole means comprises at least one stator pole mounted between the boundaries of poles Of constant magnetic field strength.

4. The commutatorless motor of claim 3, wherein said ring is comprised of an oxidized ceramic magnetic material and said stator pole is comprised of a ferrite core and an energizing coil wound thereon.

5. The commutatorless motor of claim 2 wherein said drive coils comprise first and second drive coil means, means interconnecting one end of each of said drive coil means directly, and means connecting the other ends of said drive coil means by way of said rectifying means.

6. The commutatorless motor of claim 5 in which said rectifying means comprises controlled rectifying means, wherein said controlled rectifying means is connected to said coil means wherby at any instant one of said coil means controls the direct current flowing through both of said coil means.

7. The commutatorless motor of claim 2 wherein said AC voltage source comprises high frequency generator means having a load dependent current output.

8. The commutatorless motor of claim 7 wherein said coil means on said stator comprise generator coil means in said high frequency generator means.

9. The commutatorless motor of claim 2 wherein said stator is comprised of ferrite material and forms a motor housing and a return path for magnetic fields, and wherein said poles of constant magnetic field strength are comprised of an oxidized ceramic magnetic material mounted within said housing.

10. The commutatorless motor of claim 2 wherein said coil means are positioned close to said drive coils, the pole faces of said pole means being in a common plane, the pole cores of said pole means including said drive coils as a return path for alternating field flux.

11. The commutatorless motor of claim 2 wherein said source comprises a plurality of AC voltage generators, and wherein said pole means comprises at least twice as many stator poles as said generators, said stator poles being mounted at the boundaries between poles of constant magnetic field strength.

12. The commutatorless motor of claim 2 wherein said pole means comprises a pair of stator poles positioned diametrically oppositely in said motor, said source being connected to the coil means on said stator poles.

13. The commutatorless motor of claim 2 wherein said source of voltage comprises a pair of AC voltage generators, said pole means comprising a plurality of stator poles mounted at the boundaries of poles of constant magnetic field strength, and further comprising means for selectively connecting said generators to the coil means on said stator poles for controlling the direction of rotation of said rotor.

14. The commutatorless motor of claim 2 wherein said source comprises regulating means for controlling the revolutions of said rotor.

15. The commutatorless motor of claim 14 wherein said AC voltage source comprises a pair of AC voltage generators corresponding to different directions of rotation of said rotor, and means for selectively coupling said generators to said coil means for controlling the direction of rotation of said rotor.

16. The commutatorless motor of claim 2 wherein said drive coils are mounted in respectively overlapping positions.

17. The commutatorless motor of claim 2 wherein said drive coils and rectifying means comprise an integrated component.

18. The commutatorless motor of claim 2 wherein said drive coils are comprised of printed circuits.

19. The commutatorless motor of claim 2 further comprising a stator housing comprised of a pair of cups coaxially mounted with facing open ends, said pole means comprise pole cores mounted within said cups and extending parallel to the axis thereof with the axial dimension of each pole core being shorter than the internal axial length of the corresponding cups, said poles of constant magnetic field strength comprising a ring mounted within said cups and having recesses through which said pole cores extend, and wherein said rotor is disc shaped.

20. The commutatorless motor of claim 19 further compRising a shaft bearing coaxially mounted in each of said cups, said rotor comprising a shaft rotatably mounted in said shaft bearings, said rectifying means being mounted on said rotor adjacent said shaft and within said ring.

21. The commutatorless motor of claim 2 further comprising a stator housing, said stator being mounted within said housing, said housing further having recesses within which said source is mounted, whereby the only external leads from said motor are comprised of DC supply leads connected to said source and control lead means for controlling said source.