Magnetic coupling

• US 4,207,485 A
• Filed: 04/24/1978
• Issued: 06/10/1980
• Est. Priority Date: 04/24/1978
• Status: Expired due to Term

• Current Assignee: The Garrett Corporation
• Original Assignee: The Garrett Corporation
• Inventors: Silver, Alexander
• Primary Examiner(s): Duggan, Donovan F.
• Application Number:
  US05/899,668
• Time in Patent Office: 778 Days
• Field of Search: 417/420, 417/366, 310/90, 310/54, 310/55, 310/56, 310/104, 310/103, 310/60 R, 310/61, 310/60 A
• US Class Current: 310/104
• CPC Class Codes: F04D 13/027 Details of the magnetic circuit
• CPC Class Codes: H02K 49/106 with a radial air gap
• CPC Class Codes: H02K 5/128 using air-gap sleeves or air-gap discs
• CPC Class Codes: H02K 7/08 Structural association with bearings
• CPC Class Codes: H02K 9/19 for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil

Abstract

A permanent magnet coupling having opposed magnetic coupling members, and including process fluid bearings and dual flow paths for process fluid providing temperature control.

Claims

1. A magnetic coupling for coupling rotational motion through a sealed wall comprising rotatable driving means on one side of the wall and including first magnetic means thereon;

and rotatable driven means on the side of the wall opposite said driving means and including thereon second magnetic means in magnetic coupling relation with said first magnetic means, each of said rotatable means being disposed in a respective region of process fluid and each including axial and radial passages for centrifugally establishing circulation of the associated process fluid over the magnetic means thereon.

2. A magnetic coupling as set forth in claim 1 wherein one of said rotatable means comprises an outer coupling member and the other of said rotatable means comprises an inner coupling member, said outer member being axially received over said inner member in concentrically spaced relation therewith, said wall being configured to fit concentrically between and in spaced relation with said outer and inner members.

3. A magnetic coupling as set forth in claim 2 wherein said driving means comprises the outer coupling member, and said driven means comprises the inner coupling member.

4. A magnetic coupling as set forth in claim 2 wherein said first and second magnetic means comprise first and second ring magnets, respectively.

5. A magnetic coupling as set forth in claim 1 wherein said process fluid bearings comprise foil bearings.

6. A magnetic coupling as set forth in claim 1 wherein the axial and radial passages of each of said rotatable means comprise a longitudinally extending central bore communicating between the wall and at least one outwardly radiating port formed on the side of the associated magnetic means opposite the wall whereby, upon rotation, process fluid is pumped centrifugally out of the bore through the port to cause process fluid circulation over the associated magnetic means and into the bore.

7. A magnetic coupling as set forth in claim 1 including process fluid bearings for supporting each of said rotatable means, said port of each rotatable means being formed on the side of the associated magnetic means and bearings opposite the wall whereby, upon rotation, process fluid is pumped centrifugally out of the bore of each rotatable means and through the associated port to cause circulation over the corresponding bearings and magnetic means.

8. A magnetic coupling as set forth in claim 1 wherein one of said rotatable means comprises a shaft, a cup-shaped outer member connected to said shaft and carrying the associated magnetic means, and an axially elongated central extension within said cup-shaped outer member and projecting toward the wall, said axial passage being formed through said extension and a portion of said shaft and said radial passage being formed in said shaft disposed in a region of a process fluid, said other rotatable means being formed for concentric reception within said outer member and over said extension, and said wall being configured to fit in spaced relation between said first and second coupling means.

9. A magnetic coupling for coupling rotational motion through a sealed wall comprising rotatable driving means disposed in a region of a first process fluid on one side of the wall and including first magnetic means, said driving means having formed therein a longitudinally extending central bore communicating between the wall and at least one outwardly radiating port formed therein on the side of said first magnetic means opposite the wall;

and rotatable driven means disposed in a region of a second process fluid on the other side of the wall axially aligned with said driving means and including second magnetic means in magnetic coupling relation with said first magnetic means, said driven means having formed therein a longitudinally extending central bore communicating between the wall and at least one outwardly radiating port formed therein on the side of said second magnetic means opposite the wall whereby, upon rotation, the respective process fluids are pumped centrifugally out of the associated bores through the ports to cause fluid circulation over the associated magnetic means and into the bores.

10. A magnetic coupling as set forth in claim 9 including first and second process fluid bearings for respectively supporting said driving and driven means, said ports in said driving and driven means being disposed so that, upon rotation, the respective process fluids are pumped over the associated bearings and magnetic means into the respective bores.

11. A magnetic coupling as set forth in claim 10 wherein said first and second process fluid bearings comprise foil bearings.

12. A magnetic coupling as set forth in claim 9 wherein one of said rotatable means comprises a shaft, a cup-shaped outer member connected to said shaft and carrying said first magnetic means, and an axially elongated extension within said cup-shaped outer member and projecting toward the wall, said bore in said one rotatable means being formed to extend through said extension and a portion of said shaft;

and said other rotatable means comprises a shaft, a cup-shaped inner member connected to said shaft and carrying said second magnetic means, said inner member being received concentrically within said outer member and concentrically about said axial extension, said wall being configured to fit in spaced relation between said outer and inner coupling members.

13. A magnetic coupling for coupling rotational motion through a sealed wall comprising rotatable driving means disposed in a region of a first process fluid on one side of the wall and including first magnetic means, said driving means having formed therein a longitudinally extending central bore communicating between the wall and at least one outwardly radiating port formed therein on the side of said first magnetic means opposite the wall;

first process fluid bearing means between the wall and said port for supporting said rotatable driving means;

rotatable driven means disposed in a region of a second process fluid on the other side of the wall axially aligned with said driving means and including second magnetic means in magnetic coupling relation with said first magnetic means, said driven means having formed therein a longitudinally extending central bore communicating between the wall and at least one outwardly radiating port formed therein on the side of said second magnetic means opposite the wall; and

second process fluid bearing means between the wall and the port on said driven means for supporting said driven means whereby, upon rotation, the respective process fluids are pumped centrifugally out of the associated bores through the ports to cause fluid circulation over the associated magnetic means and process fluid bearing means and into the bores.

14. A magnetic coupling as set forth in claim 13 wherein one of said rotatable means comprises a shaft, a cup-shaped outer member connected to said shaft and carrying said first magnetic means, and an axially elongated extension within said cup-shaped outer member and projecting toward the wall, said bore in said one rotatable means being formed to extend through said extension, and a portion of said shaft;

and said other rotatable means comprises a shaft, a cup-shaped inner member connected to said shaft and carrying said second magnetic means, said inner member being received concentrically within said outer member and concentrically about said axial extension, said wall being configured to fit in spaced relation between said outer and inner coupling members.

15. A magnetic coupling for coupling rotational motion through a sealed wall comprising a first shaft connected to a cup-shaped outer member carrying first magnetic means, all disposed on one side of the wall within a region of a first process fluid, said outer member including an axially elongated extension projecting toward the wall, and having formed therein a longitudinally extending central bore communicating between the wall and at least one outwardly radiating port formed in said first shaft at a position on the side of said first magnetic means opposite the wall;

and a second shaft connected to a cup-shaped inner member carrying second magnetic means disposed in a region of a second process fluid with said second magnetic means in magnetic coupling relation with said first magnetic means, said inner member being shaped for concentric reception within said outer member and about said extension, and having formed therein a longitudinally extending central bore communicating between the wall and at least one outwardly radiating port formed in said second shaft at a position on the side of said second magnetic means opposite the wall, whereby upon rotation, the respective process fluids are pumped centrifugally out of the associated bores through the ports to cause fluid circulation over the associated magnetic means and into the bores.

16. A magnetic coupling as set forth in claim 15 including first process fluid bearing means for supporting said outer member;

and second process fluid bearing means for supporting said inner member whereby, upon rotation of said inner and outer members, the respective process fluids are pumped centrifugally out of the associated bores through the ports to cause fluid circulation over the respective inner and outer members and process fluid bearing means into the bores.

17. A method of magnetically coupling rotational motion through a sealed wall comprising the steps of positioning rotatable driving means including first magnetic means on one side of the wall;

positioning rotatable driven means including second magnetic means on the other side of the wall in axial alignment with said driving means and in magnetic coupling relation with said first magnetic means; and

positioning each of said rotatable means in a respective region of process fluid, and forming axial and radial passages in each of said rotatable means for centrifugally establishing circulation of the associated process fluid over the magnetic means thereon.

18. The method of claim 17 including the steps of concentrically receiving said driving member about said driven member, and configuring the sealed wall for concentric reception between said driving and driven members in spaced relation therewith.

19. The method of claim 17 wherein said step of forming said axial and radial passages comprises the steps of forming a longitudinally extending central bore communicating between the wall and at least one outwardly radiating port formed on the side of the associated magnetic means opposite the wall whereby, upon rotation, process fluid is pumped centrifugally out of the bore through the port to cause process fluid circulation over the associated magnetic means and into the bore.

20. The method of claim 19 including the steps of supporting each of said rotatable means with process fluid bearings disposed between said port and said wall whereby fluid circulates over said bearings and the associated magnetic means into the bore.

21. The method of claim 20 wherein said supporting step includes supporting each of said rotatable means with foil bearings.

22. The method of claim 19 wherein the step of forming the outwardly radiating port comprises forming a pair of generally opposed, outwardly radiating ports.

23. The method of claim 17 including the steps of forming said driving means to include a cup-shaped outer member with an axially elongated central extension projecting toward the wall and forming said rotatable driven means to include a cup-shaped inner member for concentric reception within said outer member and about said extension.

24. A method of magnetically coupling rotational motion through a sealed wall comprising the steps of positioning rotatable driving means including first magnetic means on one side of the wall in a region of a process fluid;

forming an outwardly radiating port in said driving means on the side of the first magnetic means opposite the wall, and a longitudinally extending central bore communicating between the wall and said port;

positioning rotatable driven means including second magnetic means in a region of another process fluid on the other side of the wall in axial alignment with said driving means and in magnetic coupling relation with said first magnetic means; and

forming an outwardly radiating port in said driven means on the side of the second magnetic means opposite the wall and a longitudinally extending central bore communicating between the port in said driven means and the wall whereby, upon rotation, the process fluids are pumped centrifugally out of the associated bores through the respective ports to cause fluid circulation over the associated magnetic means and into the bores.

25. The method of claim 24 including the step of respectively supporting said driving and driven means with first and second process fluid bearings each disposed between the wall and the associated port so that fluid circulates over the respective process fluid bearings and magnetic means into the bores.

26. A method of magnetically coupling rotational motion through a sealed wall comprising the steps of positioning rotatable driving means including first magnetic means on one side of the wall in a region of a process fluid;

forming an outwardly radiating port in said driving means on the side of the first magnetic means opposite the wall, and a longitudinally extending central bore communicating between the wall and said port;

positioning rotatable driven means including second magnetic means in a region of another process fluid on the other side of the wall in axial alignment with said driving means and in magnetic coupling relation with said first magnetic means;

forming an outwardly radiating port in said driven means on the side of the second magnetic means opposite the wall, and a longitudinally extending central bore communicating between the port in said driven means and the wall; and

supporting said driving and driven members with first and second process fluid bearings respectively disposed between the wall and the adjacent port whereby, upon rotation, the process fluids are centrifugally pumped out of the associated bores through the respective ports to cause fluid circulation over the associated magnetic means and process fluid bearings into the bores.

27. A method of magnetically coupling rotational motion through a sealed wall comprising the steps of positioning driving means including first magnetic means on a cup-shaped outer member having an axially elongated central extension on one side of the wall in a region of a first process fluid;

forming an outwardly radiating port in said driving means on the side of the first magnetic means opposite the wall, and a longitudinally extending central bore communicating between the wall and said port;

positioning driven means including second magnetic means on a cup-shaped inner member in a region of a second process fluid on the other side of the wall in magnetically coupled relation with said first magnetic means with the inner member concentrically received within said outer member and about said extension; and

forming an outwardly radiating port in said driven means on the side of the second magnetic means opposite the wall, and a longitudinally extending central bore communicating between the port in said driven means and the wall whereby, upon rotation, the process fluids are pumped centrifugally out of the associated bores through the respective ports to cause fluid circulation over the associated magnetic means and into the bores.

28. The method of claim 27 including the step of respectively supporting said driving and driven means with first and second process fluid bearings each disposed between the wall and the associated port so that fluid circulates over the respective process fluid bearings and magnetic means into the bores.