Induced current position transducer having a low power electronic circuit
US6011389A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 1997 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | Aug 18, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/2046
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An inductive transducer system for use in high accuracy applications such as linear or rotary encoders, employs two members movable relative to each other. A first, active member induces eddy currents in a second, passive member that lacks a power source or electrical wires connected thereto. The first, active member contains both a transmitter for generating a magnetic field and a receiver for receiving the field. The receiver has a plurality of symmetric loops. Electronic circuitry coupled to the receiver evaluates the relative position between the two members as the passive member disrupts the magnetic field received by the receiver. The inductive transducer can be readily manufactured using known printed circuit board technology, and is substantially immune to contamination by particles, including ferromagnetic particles, oil, water and other fluids. A pulse-driven drive circuit allows the inductive transducer to consume little power, and thus allows the transducer to be readily incorporated into hand-held, battery-powered measurement tools.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.