Oil impregnated porous bearing units and motors provided with same
US5834870A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 1997 |
| Grant date | Nov 10, 1998 |
| Priority date | — |
| Expiry date | May 19, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2380/26
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An oil impregnated porous bearing unit includes an arrangement wherein an oil impregnated porous bearing containing ferro-fluid is fixed in a non-magnetizable housing, a ring shaped permanent magnet is disposed so that the ferro-fluid will exist in a gap between a rotary shaft, whereon the ring shaped permanent magnet is fixed, and the oil impregnated porous bearing, and the ferro-fluid circulates between a slide plane of the bearing and a body of the oil impregnated porous bearing with rotation of the rotary shaft by utilizing the magnetic attractive force of the permanent magnet and a capillary phenomenon in the oil impregnated porous bearing. In addition, a spiral groove may be provided in an exterior circumferential surface of the permanent magnet fixed to the rotary shaft or in an interior circumferential surface of the housing facing the above exterior circumferential surface of the permanent magnet in order to generate dynamic pressure at the spiral groove portion with rotation of the rotary shaft so as to supply ferro-fluid to the oil impregnated porous bearing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.