Amplification circuit for increasing variable reluctance sensor output
US6909277B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 13, 2002 |
| Grant date | Jun 21, 2005 |
| Priority date | — |
| Expiry date | Mar 13, 2022 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D41/0097
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for measuring a characteristic, such as speed, of a machine. A variable reluctance sensor (VRS) is coupled to a resistive element, which filters a portion of a basic output signal generated by the VRS having a frequency above a prescribed threshold level, thus removing high-frequency noise from the basic output signal. An amplifier amplifies the filtered output signal. The filtered, amplified output signal has an increased signal-to-noise ratio such that the machine characteristic, i.e. speed, can be more accurately measured during a slow speed operation. A controller generates a control signal received by a switching device to decouple the resistive element when machine speed exceeds a prescribed threshold level. Then, the basic output signal is used to measure the characteristic of the machine during normal machine operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.