Claims
- 1. A bearing apparatus comprising a housing formed of a non-magnetizable material and having a bottom portion;
- a fluid lubricating type radial bearing means coaxially disposed with respect to said housing and having a magnetic fluid sealing section and a radial bearing section; a thrust bearing means provided at the bottom portion of said housing; and a rotating shaft of a permeable material rotatably supported by said radial bearing means and said thrust bearing means so as to extend through said radial bearing means; said magnetic fluid sealing section being disposed on and open side of said housing with a predetermined spacing away from said radial bearing section whereby a space is provided between said magnetic fluid sealing section and a liquid surface of fluid lubricant filled in said radial bearing section.
- 2. A bearing apparatus as set forth in claim 1, wherein said fluid lubricant filled in said radial bearing section is the same magnetic fluid as that in said magnetic fluid sealing section.
- 3. A bearing apparatus as set forth in one of claims 1 or 2, wherein said fluid lubricant filled in said radial bearing section is a magnetic fluid having a lower viscosity than that of the magnetic fluid in said magnetic fluid sealing section.
- 4. A bearing apparatus as set forth in claim 3, wherein the fluid lubricant circulates between opposite end surfaces of said radial bearing section.
- 5. A bearing apparatus as set forth in claim 4, wherein an area, at which a circulating passage of said fluid lubricant contacts with said rotating shaft, is larger around the lower end surface of said radial bearing section than around the upper end surface thereof.
- 6. A bearing apparatus as set forth in claim 5, further comprising a passage means extended between the opposite end surfaces of said radial bearing section for passing a fluid lubricant therethrough and provided on and outer periphery of said radial bearing section in communication with a bearing clearance between said radial bearing section and said rotating shaft.
- 7. A bearing apparatus as set forth in claim 6, wherein a surface opposite to a sliding surface of said thrust bearing section which bears an axial load of said rotating shaft cooperates with the bottom of said housing to define therebetween a chamber, and a passage means for the fluid lubricant is provided on central and outer peripheral portions of said sliding surface to communicate with said chamber.
- 8. A bearing apparatus as set forth in claim 7, further comprising at least one groove provided on one of the sliding surface of said radial bearing section or on the sliding surface of said rotating shaft to serve for circulation of the fluid lubricant.
- 9. A bearing apparatus as set forth in claim 8, wherein the fluid lubricant flows along the sliding surface of said radial bearing from the open side of said housing to the bottom thereof.
- 10. A bearing apparatus as set forth in claim 1, wherein said magnetic fluid sealing section disposed on the open side of said housing comprises a ring-shaped permanent magnet and a single pole piece.
- 11. A bearing apparatus as set forth in claim 10, further comprising a non-magnetizable disk, and wherein said pole piece is disposed on a side of said radial bearing section and said non-magnetizable disk is disposed on the open side of said housing such that said pole piece and said non-magnetizable disk are disposed in close proximity to said permanent magnet.
- 12. A bearing apparatus as set forth in claim 11, wherein a gap between said non-magnetizable disk and said rotating shaft is one of equal in size to a bearing clearance about said radial bearing section or smaller than a gap between said pole piece and said rotating shaft.
- 13. A bearing apparatus as set forth in claim 12, wherein said non-magnetizable disk is formed of a material having a lower hardness than that of a material which forms said rotating shaft.
- 14. A bearing apparatus as set forth in claim 10, wherein said permanent magnet is substantially L-shaped in axial section.
- 15. A bearing apparatus as set forth in one of claims 1 or 2, wherein the fluid lubricant circulates between opposite end surfaces of said radial bearing section.
- 16. A bearing apparatus as set forth in claim 15, wherein an area, at which a circulating passage of said fluid lubricant contacts with said rotating shaft, is larger around the lower end surface of said radial bearing section then around the upper end surface thereof.
- 17. A bearing apparatus as set forth in claim 16, further comprising passage means extending between the opposite end surfaces of said radial bearing section for passing therethrough a fluid lubricant and provided on an outer periphery of said radial bearing section and communication with a bearing clearance between said radial bearing section and said rotating shaft.
- 18. A bearing apparatus as set forth in claim 17, wherein a surface opposite to a sliding surface of said thrust bearing section which bears an axial load of said rotating shaft cooperates with the bottom of said housing to define therebetween a chamber, and a passage means for the fluid lubricant is provide on central and outer peripheral portions of said sliding surface to communicate with said chamber.
- 19. A bearing apparatus as set forth in claim 18, further comprising at least one groove provided on one of the sliding surface of said radial bearing section or on the sliding surface of sail rotating shaft to serve for circulation of the fluid lubricant.
- 20. A bearing apparatus as set forth in claim 19, wherein the fluid lubricant flows along the sliding surface of said radial bearing section from the open side of said housing to the bottom thereof. .Iadd.
- 21. A bearing apparatus comprising:
- a housing formed of a non-magnetizable material and having a bottom portion;
- a fluid lubricating type radial bearing means disposed with respect to said housing and having a magnetic fluid sealing section and a radial bearing section; and
- a rotating shaft of a permeable material rotatably supported by said radial bearing means so as to extend through said radial bearing means,
- wherein said magnetic fluid sealing section is disposed on an open side of said housing with a predetermined spacing away from said radial bearing section, whereby a space is provided between said magnetic fluid sealing section and a liquid surface of magnetic fluid lubricant filled in said radial bearing section. .Iaddend..Iadd.
- 22. A bearing apparatus comprising:
- a housing formed of a non-magnetizable material;
- a fluid lubricating type radial bearing means disposed with respect to said housing and having a magnetic fluid sealing section and a radial bearing section; and
- a rotating shaft of a permeable material rotatably supported by said radial bearing means so as to extend through said radial bearing means,
- wherein said magnetic fluid sealing section is disposed in said housing with a predetermined spacing away from said radial bearing section, whereby a space is provided between said magnetic fluid sealing section and a liquid surface of magnetic fluid lubricant filled in said radial bearing section. .Iaddend..Iadd.23. A bearing apparatus comprising:
- a housing formed of a non-magnetizable material;
- a fluid lubricating type radial bearing means disposed with respect to said housing and having a magnetic fluid sealing section and a radial bearing section; and
- a rotating shaft of a permeable material rotatably supported by said radial bearing means so as to extend through said radial bearing means,
- wherein said magnetic fluid sealing section is disposed in said housing with a predetermined spacing away from said radial bearing section, whereby a space is defined at least by said magnetic fluid sealing section, a portion of said housing and a liquid surface of magnetic fluid
- lubricant filled in said radial bearing section. .Iaddend..Iadd.24. A bearing apparatus comprising:
- a housing formed of a non-magnetizable material;
- a fluid lubricating type radial bearing means disposed with respect to said housing and having a magnetic fluid sealing section and a radial bearing section containing a radial bearing; and
- a rotating shaft of a permeable material rotatably supported by said radial bearing means so as to extend through said radial bearing means,
- wherein said magnetic fluid sealing section is disposed in said housing with a predetermined spacing away from said bearing section, and
- wherein said radial bearing is located relative to said rotating shaft so that a magnetic fluid lubricant filled in said radial bearing section will
- circulate in said radial bearing section. .Iaddend..Iadd.25. A bearing apparatus according to one of claims 21, 22, 23 or 24, wherein at least one groove is provided on one of the sliding surface of the radial bearing and the sliding surface of said rotating shaft to serve for circulation of
- the fluid lubricant. .Iaddend..Iadd.26. A bearing apparatus comprising:
- a housing formed of a non-magnetizable material;
- a fluid lubricating type radial bearing means disposed with respect to said housing and having a magnetic fluid sealing section and a radial bearing section; and
- a rotating shaft of a permeable material rotatably supported by said radial bearing means so as to extend through said radial bearing means,
- wherein said magnetic fluid sealing section is disposed in said housing with a predetermined spacing away from said radial bearing section, whereby a space is defined at least by said magnetic fluid sealing section and a liquid surface of magnetic fluid lubricant filled in said radial bearing section. .Iaddend.
Priority Claims (1)
Number |
Date |
Country |
Kind |
63-152333 |
Jun 1988 |
JPX |
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Parent Case Info
.Iadd.This application is a Continuation of Ser. No. 07/908,419, filed Jul. 6, 1992, now abandoned. .Iaddend.
US Referenced Citations (8)
Foreign Referenced Citations (9)
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DEX |
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DEX |
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JPX |
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JPX |
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GBX |
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Non-Patent Literature Citations (2)
Entry |
"Tribology", p. 20, Mar., 1988 (Japanese). |
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Continuations (1)
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Number |
Date |
Country |
Parent |
908419 |
Jul 1992 |
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Reissues (1)
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Number |
Date |
Country |
Parent |
368836 |
Jun 1989 |
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