Magnetic fluid sealed bearing

Abstract

The present invention provides a magnetic fluid sealed bearing having a stable sealing performance and allowing easy build-in of a magnetic sealing mechanism into the bearing. The magnetic fluid sealed bearing according to the present invention comprises: an inner ring and an outer ring formed of a magnetic material; a plurality of rolling members disposed between the inner ring and the outer ring; a ring-shaped polar plate formed of a magnetic material and mounted on an inner circumferential surface of the outer ring such that a gap is produced between the ring-shaped polar plate and an outer circumferential surface of the inner ring; a ring-shaped magnet attached to an axially inner side surface of the ring-shaped polar plate, the ring-shaped magnet being magnetized such that magnetic poles thereof point to axial directions and forming magnetic circuits on both the outer ring side and the inner ring side, the ring-shaped magnet having a smaller radial length than the ring-shaped polar plate; and an inner ring magnetic fluid retained in the magnetic circuit on the inner ring side for sealing the gap, wherein the ring-shaped polar plate includes a constraining portion configured to constrain the ring-shaped magnet from moving in an axial direction and a radial direction for positioning and fixing the ring-shaped magnet.

Description

technical field [0001] The present invention relates to a bearing with a magnetic fluid seal which is arranged in various power transmission mechanisms and rotatably supports a rotating shaft while preventing foreign matter such as dust and moisture will not go inside. Background technique [0002] In general, a rotating shaft provided in various driving force transmission mechanisms is rotatably supported via bearings. At this time, many bearings use so-called ball bearings in which a plurality of rolling elements (rolling elements) are accommodated in the circumferential direction between the inner ring and the outer ring. By using this type of bearing, the Improvement of the rotation performance of the rotary shaft. [0003] Although such a bearing is used as a support unit for a rotating shaft of a driving force transmission mechanism on various driving devices, depending on the driving device, there are cases where it is desired to prevent foreign matter such as dust ...

AI Technical Summary

Problems solved by technology

[0003] Although such a bearing is used as a support unit for the rotating shaft of the driving force transmission mechanism on various driving devices, depending on the driving device, there are cases where it is desired to prevent foreign matter such as dust and moisture from entering the inside through the bearing portion

In addition, when foreign matter enters the bearing itself, problems such as deterioration of rotation performance or generation of abnormal sound occur.

Images