Polyphase motor, particularly for driving an indicator needle

• US 5,880,551 A
• Filed: 10/21/1997
• Issued: 03/09/1999
• Est. Priority Date: 10/21/1996
• Status: Expired due to Term

• Current Assignee: MMT SA
• Original Assignee: Sonceboz SA
• Inventors: Prudham, Daniel
• Primary Examiner(s): Ramirez, Nestor
• Assistant Examiner(s): Waks, Joseph
• Application Number:
  US08/955,357
• Time in Patent Office: 504 Days
• Field of Search: 310/153, 310/162, 310/216, 310/254, 310/156
• US Class Current: 310/261.1
• CPC Class Codes: G01R 7/06 moving-iron type
• CPC Class Codes: H02K 21/14 with magnets rotating within the armatures
• CPC Class Codes: H02K 37/14 with magnets rotating within the armatures
• CPC Class Codes: H02K 7/116 with gears

Abstract

A polyphase motor formed by a stationary member excited by electric coils and by a magnetized rotor. The rotor has N pairs of poles magnetized radially in alternating directions, N being equal to 4 or 5. The stationary member has at least two W-shaped circuits each including an electric coil surrounding the central strut. The W-shaped circuits are arranged so that when one of the central struts is opposite a magnetic transition, the other central strut is roughly opposite a magnetic pole. Pole shoes of the central struts of the two W-shaped circuits can also be spaced at 120° angles.

Claims

1. A polyphase motor comprising:

a stationary member excited by electric coils and by a magnetized rotor, the magnetized rotor having N pairs of poles magnetized radially in alternating directions separated by magnetic transitions, N being equal to 4 or 5; and

wherein the stationary member includes at least first and second W-shaped circuits, said at least first and second W-shaped circuits including respective first and second central struts with respective first and second pole shoes, each of said at least first and second W-shaped circuits being arranged so that when the first central strut is opposite a magnetic transition of the magnetized rotor, the second central strut is roughly opposite a magnetic pole, and the first and second pole shoes of the first and second central struts of the at least first and second W-shaped circuits being angularly displaced by an angle roughly equal to 120°

.

2. A polyphase motor in accordance with claim 1, wherein the at least first and second W-shaped circuits are separated by 120°

and each of the at least first and second W-shaped circuit further includes an electric coil fed by 120°

dephased signals.

3. A polyphase motor in accordance with claim 1, wherein the stationary member further includes a third W-shaped circuit separated by 120°

from the at least first and second W-shaped circuits, each of said first, second and third W-shaped circuits further including an electric coil fed by 120°

dephased signals.

4. A polyphase motor in accordance with claim 2, wherein each of the at least first and second W-shaped circuits further includes exterior struts connected by a notched segment shaped of a circular arc.

5. A polyphase motor in accordance with claim 4, wherein the notched segment has stationary teeth.

6. A polyphase motor in accordance with claim 1, wherein the stationary member has a hollow central portion with dimensions which allow insertion of an electric coil in a plane of the first and second central struts and positioning around a corresponding of the first and second central strut via translation.

7. A polyphase motor in accordance with claim 1, wherein the first and second central struts bear electric coils and extend radially.

8. A polyphase motor in accordance with claim 1, wherein the stationary member is made up of a stack of metal sheets.

9. A polyphase motor in accordance with claim 1, wherein a front end of the first and second pole shoes is located in a plane of a front internal face of an electric coil of each of the at least first and second W-shaped circuits.

10. A polyphase motor in accordance with claim 1, wherein the rotor is formed by a magnet magnetized according to a direction perpendicular to a plane of the stationary member, and the rotor is placed between two notched disks with staggered teeth.

11. A polyphase motor as stated in claim 1, wherein the rotor is formed by a ring magnetized in a scalloped fashion.

12. A polyphase motor as stated in claim 1, further comprising an auxiliary flux closure part.

13. A polyphase motor in accordance with claim 11, further comprising a magnetic flux closure part which is a cylindrical part in a shape of a ring with grooves forming teeth placed opposite teeth.

14. A polyphase motor comprising:

a stationary member excited by electric coils and by a magnetized rotor, the magnetized rotor having N pairs of poles magnetized radially in alternating directions separated by magnetic transitions, N being equal to 4 or 5; and

wherein the stationary member includes at least first and second W-shaped circuits, said at least first and second W-shaped circuits including respective first and second central struts with respective first and second pole shoes, each of said at least first and second W-shaped circuits being arranged so that when the first central strut is opposite a magnetic transition of the magnetized rotor, the second central strut is roughly opposite a magnetic pole.

15. A polyphase motor in accordance with claim 14, wherein the at least first and second W-shaped circuits are separated by 120°

and each of the at least first and second W-shaped circuit further includes an electric coil fed by 120°

dephased signals.

16. A polyphase motor in accordance with claim 14, wherein the stationary member further includes a third W-shaped circuit separated by 120°

from the at least first and second W-shaped circuits, each of said first, second and third W-shaped circuits further including an electric coil fed by 120°

dephased signals.

17. A polyphase motor comprising:

a stationary means excited by electric coil means and by a magnetized rotor means, the magnetized rotor means having N pairs of poles magnetized radially in alternating directions separated by magnetic transitions, N being equal to 4 or 5; and

wherein the stationary means includes at least first and second W-shaped circuit means, said at least first and second W-shaped circuit means including respective first and second central strut means with respective first and second pole shoe means, each of said at least first and second W-shaped circuit means being arranged so that when the first central strut means is opposite a magnetic transition of the magnetized rotor means, the second central strut means is roughly opposite a magnetic pole, and the first and second pole shoe means of the first and second central strut means of the at least first and second W-shaped circuit means being angularly displaced by an angle roughly equal to 120°

.

18. A polyphase motor in accordance with claim 17, wherein the at least first and second W-shaped circuit means are separated by 120°

and each of the at least first and second W-shaped circuit means further includes an electric coil means fed by 120°

dephased signals.

19. A polyphase motor in accordance with claim 17, wherein the stationary means further includes a third W-shaped circuit means separated by 120°

from the at least first and second W-shaped circuit means, each of said first, second and third W-shaped circuit means further including an electric coil means fed by 120°

dephased signals.