Rolling bearing unit with rotational speed detection device having a tone wheel and a sensor
US5614822A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1995 |
| Grant date | Mar 25, 1997 |
| Priority date | — |
| Expiry date | Jan 30, 2015 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2326/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A rolling bearing unit has a rotational speed detection device which has a sensor having a yoke, a pair of permanent magnets, a coil, and a tone wheel. The tone wheel is made by press-forming a magnetic metal plate so as to form a cylindrical support base secured onto an end portion of the bearing unit. The tone wheel has a ring-shaped first detecting part which is bent radially outward from the inner rim of the cylindrical support base, and a cylindrical shaped second detecting part which extends axially from the outer peripheral rim of the first detecting part. The first and second detecting parts have a ferro-magnetic first portion and a non-magnetic second portion, and the yoke has opposite ends which are faced to the first and second portions. The permanent magnets have like poles faced toward each other so that magnetic fluxes flow alternately through the yoke corresponding to the rotation of the tone wheel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.