Inductive displacement sensors
US4991301A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 10, 1989 |
| Grant date | Feb 12, 1991 |
| Priority date | — |
| Expiry date | Feb 10, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C9/06
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Two members 21,22 are relatively displaceable along a linear or circular path. One member 21 provides a plurality of coil portions along the path. Their individual inductances are dependent on the configuration of the second member 22. For example, the first member 21 may be an annular stator with inward radial projections k,l,m . . . on which the coil portions are wound, alternately in different senses so that the flux path tends to loop in and out. The second member 22 may be an annular rotor, one section 23 being ferromagnetic and the other section 24 being non-ferromagnetic and/or having a conductive screening layer. Alternatively the second member may be mercury 42 half-filling an annular conduit 40 which surrounds a static ferromagnetic core 44 (FIG. 9). A particular characteristic is that for any relative position of 21 and 22, half the coil portions of 21 have a different inductance from the other half.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.